that a crossbar array is basically a storage system, with an open switch representing a zero and a closed switch representing a one. you read the data by probing the switch with a small voltage. like everything else at the nanoscale, the switches and wires of a crossbar are bound to be plagued by at least some nonfunctional components. these components will be only a few atoms wide, and the second law of thermodynamics ensures that we will not be able to completely specify the position of every atom. however, a crossbar architecture builds in redundancy by allowing you to route around any parts of the circuit that don ’ t work. because of their simplicity, crossbar arrays have a much higher density of switches than a comparable integrated circuit based on transistors. but implementing such a storage system was easier said than done. many research groups were working on such a cross - point memory — and had been since the 1950s. even after 40 years of research, they had no product on the market. still, that didn ’ t stop them from trying. that ’ s because the potential for a truly nanoscale crossbar memory is staggering ; picture carrying around the entire library of congress on a thumb drive. one of the major impediments for prior crossbar memory research was the small off - to - on resistance ratio of the switches ( 40 years of research had never produced anything surpassing a factor of 2 or 3 ). by comparison, modern transistors have an off - to - on resistance ratio of 10 000 to 1. we calculated that to get a high - performance memory, we had to make switches with a resistance ratio of at least 1000 to 1. in other words, in its off state, a switch had to be 1000 times as resistive to the flow of current as it was in its on state. what mechanism could possibly give a nanometer - scale device a three - orders - of - magnitude resistance ratio? we found the answer in scanning tunneling microscopy ( stm ), an area of research i had been pursuing for a decade. a tunneling microscope generates atomic - resolution images by scanning a very sharp needle across a surface and measuring the electric current that flows between the atoms at the tip of the needle and the surface the needle is probing. the general rule of thumb in stm is that moving that tip 0. 1 nm closer to a surface increases the tunneling current by one order of magnitude. we needed some similar mechanism by which we could change the effective spacing


needle is probing. the general rule of thumb in stm is that moving that tip 0. 1 nm closer to a surface increases the tunneling current by one order of magnitude. we needed some similar mechanism by which we could change the effective spacing between two wires in our crossbar by 0. 3 nm. if we could do that, we would have the 1000 : 1 electrical switching ratio we needed. our constraints were getting ridiculous. where would we find a material that could change its physical dimensions like that? that is how we found ourselves in the realm of molecular electronics. conceptually, our device was like a tiny sandwich. two platinum electrodes ( the intersecting wires of the crossbar junction ) functioned as the ” bread ” on either end of the device. we oxidized the surface of the bottom platinum wire to make an extremely thin layer of platinum dioxide, which is highly conducting. next, we assembled a dense film, only one molecule thick, of specially designed switching molecules. over this ” monolayer ” we deposited a 2 - to 3 - nm layer of titanium metal, which bonds strongly to the molecules and was intended to glue them together. the final layer was the top platinum electrode. the molecules were supposed to be the actual switches. we built an enormous number of these devices, experimenting with a wide variety of exotic molecules and configurations, including rotaxanes, special switching molecules designed by james heath and fraser stoddart at the university of california, los angeles. the rotaxane is like a bead on a string, and with the right voltage, the bead slides from one end of the string to the other, causing the electrical resistance of the molecule to rise or fall, depending on the direction it moves. heath and stoddart ’ s devices used silicon electrodes, and they worked, but not well enough for technological applications : the off - to - on resistance ratio was only a factor of 10, the switching was slow, and the devices tended to switch themselves off after 15 minutes. our platinum devices yielded results that were nothing less than frustrating. when a switch worked, it was spectacular : our off - to - on resistance ratios shot past the 1000 mark, the devices switched too fast for us to even measure, and having switched, the device ’ s resistance state remained stable for years ( we still have some early devices we test every now and then, and we have never seen a significant change in resistance ). but our fantastic results were inconsistent. worse yet, the success or failure of a


’ s resistance state remained stable for years ( we still have some early devices we test every now and then, and we have never seen a significant change in resistance ). but our fantastic results were inconsistent. worse yet, the success or failure of a device never seemed to depend on the same thing. we had no physical model for how these devices worked. instead of rational engineering, we were reduced to performing huge numbers of edisonian experiments, varying one parameter at a time and attempting to hold all the rest constant. even our switching molecules were betraying us ; it seemed like we could use anything at all. in our desperation, we even turned to long - chain fatty acids — essentially soap — as the molecules in our devices. there ’ s nothing in soap that should switch, and yet some of the soap devices switched phenomenally. we also made control devices with no molecule monolayers at all. none of them switched. we were frustrated and burned out. here we were, in late 2002, six years into our research. we had something that worked, but we couldn ’ t figure out why, we couldn ’ t model it, and we sure couldn ’ t engineer it. that ’ s when greg snider, who had worked with kuekes on the teramac, brought me the chua memristor paper from the september 1971 ieee transactions on circuits theory. ” i don ’ t know what you guys are building, ” he told me, ” but this is what i want. ” to this day, i have no idea how greg happened to come across that paper. few people had read it, fewer had understood it, and fewer still had cited it. at that point, the paper was 31 years old and apparently headed for the proverbial dustbin of history. i wish i could say i took one look and yelled, ” eureka! ” but in fact, the paper sat on my desk for months before i even tried to read it. when i did study it, i found the concepts and the equations unfamiliar and hard to follow. but i kept at it because something had caught my eye, as it had greg ’ s : chua had included a graph that looked suspiciously similar to the experimental data we were collecting. the graph described the current - voltage ( i - v ) characteristics that chua had plotted for his memristor. chua had called them ” pinched - hysteresis loops ” ; we called our i - v characteristics ” bow ties. ” a pinched hyst


voltage ( i - v ) characteristics that chua had plotted for his memristor. chua had called them ” pinched - hysteresis loops ” ; we called our i - v characteristics ” bow ties. ” a pinched hysteresis loop looks like a diagonal infinity symbol with the center at the zero axis, when plotted on a graph of current against voltage. the voltage is first increased from zero to a positive maximum value, then decreased to a minimum negative value and finally returned to zero. the bow ties on our graphs were nearly identical [ see graphic, ” bow ties ” ]. that ’ s not all. the total change in the resistance we had measured in our devices also depended on how long we applied the voltage : the longer we applied a positive voltage, the lower the resistance until it reached a minimum value. and the longer we applied a negative voltage, the higher the resistance became until it reached a maximum limiting value. when we stopped applying the voltage, whatever resistance characterized the device was frozen in place, until we reset it by once again applying a voltage. the loop in the i - v curve is called hysteresis, and this behavior is startlingly similar to how synapses operate : synaptic connections between neurons can be made stronger or weaker depending on the polarity, strength, and length of a chemical or electrical signal. that ’ s not the kind of behavior you find in today ’ s circuits. looking at chua ’ s graphs was maddening. we now had a big clue that memristance had something to do with our switches. but how? why should our molecular junctions have anything to do with the relationship between charge and magnetic flux? i couldn ’ t make the connection. two years went by. every once in a while i would idly pick up chua ’ s paper, read it, and each time i understood the concepts a little more. but our experiments were still pretty much trial and error. the best we could do was to make a lot of devices and find the ones that worked. but our frustration wasn ’ t for nothing : by 2004, we had figured out how to do a little surgery on our little sandwiches. we built a gadget that ripped the tiny devices open so that we could peer inside them and do some forensics. when we pried them apart, the little sandwiches separated at their weakest point : the molecule layer. for the first time, we could get a good look at what was going on inside. we were in for


them and do some forensics. when we pried them apart, the little sandwiches separated at their weakest point : the molecule layer. for the first time, we could get a good look at what was going on inside. we were in for a shock. what we had was not what we had built. recall that we had built a sandwich with two platinum electrodes as the bread and filled with three layers : the platinum dioxide, the monolayer film of switching molecules, and the film of titanium. but that ’ s not what we found. under the molecular layer, instead of platinum dioxide, there was only pure platinum. above the molecular layer, instead of titanium, we found an unexpected and unusual layer of titanium dioxide. the titanium had sucked the oxygen right out of the platinum dioxide! the oxygen atoms had somehow migrated through the molecules and been consumed by the titanium. this was especially surprising because the switching molecules had not been significantly perturbed by this event — they were intact and well ordered, which convinced us that they must be doing something important in the device. the chemical structure of our devices was not at all what we had thought it was. the titanium dioxide — a stable compound found in sunscreen and white paint — was not just regular titanium dioxide. it had split itself up into two chemically different layers. adjacent to the molecules, the oxide was stoichiometric tio 2, meaning the ratio of oxygen to titanium was perfect, exactly 2 to 1. but closer to the top platinum electrode, the titanium dioxide was missing a tiny amount of its oxygen, between 2 and 3 percent. we called this oxygen - deficient titanium dioxide tio 2 - x, where x is about 0. 05. because of this misunderstanding, we had been performing the experiment backward. every time i had tried to create a switching model, i had reversed the switching polarity. in other words, i had predicted that a positive voltage would switch the device off and a negative voltage would switch it on. in fact, exactly the opposite was true. it was time to get to know titanium dioxide a lot better. they say three weeks in the lab will save you a day in the library every time. in august of 2006 i did a literature search and found about 300 relevant papers on titanium dioxide. i saw that each of the many different communities researching titanium dioxide had its own way of describing the compound. by the end of the month, the pieces had fallen into place. i finally knew how our device worked. i knew why we had a


. i saw that each of the many different communities researching titanium dioxide had its own way of describing the compound. by the end of the month, the pieces had fallen into place. i finally knew how our device worked. i knew why we had a memristor. the exotic molecule monolayer in the middle of our sandwich had nothing to do with the actual switching. instead, what it did was control the flow of oxygen from the platinum dioxide into the titanium to produce the fairly uniform layers of tio 2 and tio 2 - x. the key to the switching was this bilayer of the two different titanium dioxide species [ see diagram, ” how memristance works ” ]. the tio 2 is electrically insulating ( actually a semiconductor ), but the tio 2 - x is conductive, because its oxygen vacancies are donors of electrons, which makes the vacancies themselves positively charged. the vacancies can be thought of like bubbles in a glass of beer, except that they don ’ t pop — they can be pushed up and down at will in the titanium dioxide material because they are electrically charged. now i was able to predict the switching polarity of the device. if a positive voltage is applied to the top electrode of the device, it will repel the ( also positive ) oxygen vacancies in the tio 2 - x layer down into the pure tio 2 layer. that turns the tio 2 layer into tio 2 - x and makes it conductive, thus turning the device on. a negative voltage has the opposite effect : the vacancies are attracted upward and back out of the tio 2, and thus the thickness of the tio 2 layer increases and the device turns off. this switching polarity is what we had been seeing for years but had been unable to explain. on 20 august 2006, i solved the two most important equations of my career — one equation detailing the relationship between current and voltage for this equivalent circuit, and another equation describing how the application of the voltage causes the vacancies to move — thereby writing down, for the first time, an equation for memristance in terms of the physical properties of a material. this provided a unique insight. memristance arises in a semiconductor when both electrons and charged dopants are forced to move simultaneously by applying a voltage to the system. the memristance did not actually involve magnetism in this case ; the integral over the voltage reflected how far the dopants had moved and thus how


both electrons and charged dopants are forced to move simultaneously by applying a voltage to the system. the memristance did not actually involve magnetism in this case ; the integral over the voltage reflected how far the dopants had moved and thus how much the resistance of the device had changed. we finally had a model we could use to engineer our switches, which we had by now positively identified as memristors. now we could use all the theoretical machinery chua had created to help us design new circuits with our devices. triumphantly, i showed the group my results and immediately declared that we had to take the molecule monolayers out of our devices. skeptical after years of false starts and failed hypotheses, my team reminded me that we had run control samples without molecule layers for every device we had ever made and that those devices had never switched. and getting the recipe right turned out to be tricky indeed. we needed to find the exact amounts of titanium and oxygen to get the two layers to do their respective jobs. by that point we were all getting impatient. in fact, it took so long to get the first working device that in my discouragement i nearly decided to put the molecule layers back in. a month later, it worked. we not only had working devices, but we were also able to improve and change their characteristics at will. but here is the real triumph. the resistance of these devices stayed constant whether we turned off the voltage or just read their states ( interrogating them with a voltage so small it left the resistance unchanged ). the oxygen vacancies didn ’ t roam around ; they remained absolutely immobile until we again applied a positive or negative voltage. that ’ s memristance : the devices remembered their current history. we had coaxed chua ’ s mythical memristor off the page and into being. emulating the behavior of a single memristor, chua showed, requires a circuit with at least 15 transistors and other passive elements. the implications are extraordinary : just imagine how many kinds of circuits could be supercharged by replacing a handful of transistors with one single memristor. the most obvious benefit is to memories. in its initial state, a crossbar memory has only open switches, and no information is stored. but once you start closing switches, you can store vast amounts of information compactly and efficiently. because memristors remember their state, they can store data indefinitely, using energy only when you toggle or read


, and no information is stored. but once you start closing switches, you can store vast amounts of information compactly and efficiently. because memristors remember their state, they can store data indefinitely, using energy only when you toggle or read the state of a switch, unlike the capacitors in conventional dram, which will lose their stored charge if the power to the chip is turned off. furthermore, the wires and switches can be made very small : we should eventually get down to a width of around 4 nm, and then multiple crossbars could be stacked on top of each other to create a ridiculously high density of stored bits. greg snider and i published a paper last year showing that memristors could vastly improve one type of processing circuit, called a field - programmable gate array, or fpga. by replacing several specific transistors with a crossbar of memristors, we showed that the circuit could be shrunk by nearly a factor of 10 in area and improved in terms of its speed relative to power - consumption performance. right now, we are testing a prototype of this circuit in our lab. and memristors are by no means hard to fabricate. the titanium dioxide structure can be made in any semiconductor fab currently in existence. ( in fact, our hybrid circuit was built in an hp fab used for making inkjet cartridges. ) the primary limitation to manufacturing hybrid chips with memristors is that today only a small number of people on earth have any idea of how to design circuits containing memristors. i must emphasize here that memristors will never eliminate the need for transistors : passive devices and circuits require active devices like transistors to supply energy. the potential of the memristor goes far beyond juicing a few fpgas. i have referred several times to the similarity of memristor behavior to that of synapses. right now, greg is designing new circuits that mimic aspects of the brain. the neurons are implemented with transistors, the axons are the nanowires in the crossbar, and the synapses are the memristors at the cross points. a circuit like this could perform real - time data analysis for multiple sensors. think about it : an intelligent physical infrastructure that could provide structural assessment monitoring for bridges. how much money — and how many lives — could be saved? i ’ m convinced that eventually the memristor will change circuit design


mercury in the morning the planet mercury - - the planet closest to the sun - - is just peeking into view in the east at dawn the next few days. it looks like a fairly bright star. it ' s so low in the sky, though, that you need a clear horizon to spot it, and binoculars wouldn ' t hurt. mercury is a bit of a puzzle. it has a big core that ' s made mainly of iron, so it ' s quite dense. because mercury is so small, the core long ago should ' ve cooled enough to form a solid ball. yet the planet generates a weak magnetic field, hinting that the core is still at least partially molten. the solution to this puzzle may involve an iron " snow " deep within the core. the iron in the core is probably mixed with sulfur, which has a lower melting temperature than iron. recent models suggest that the sulfur may have kept the outer part of the core from solidifying - - it ' s still a hot, thick liquid. as this mixture cools, though, the iron " freezes " before the sulfur does. small bits of solid iron fall toward the center of the planet. this creates convection currents - - like a pot of boiling water. the motion is enough to create a " dynamo " effect. like a generator, it produces electrical currents, which in turn create a magnetic field around the planet. observations earlier this year by the messenger spacecraft seem to support that idea. but messenger will provide much better readings of what ' s going on inside mercury when it enters orbit around the planet in 2011. script by damond benningfield, copyright 2008 for more skywatching tips, astronomy news, and much more, read stardate magazine.


in 1962 president john f. kennedy ’ s administration narrowly averted possible nuclear war with the ussr, when cia operatives spotted soviet surface - to - surface missiles in cuba, after a six - week gap in intelligence - gathering flights. in their forthcoming book blind over cuba : the photo gap and the missile crisis, co - authors david barrett and max holland make the case that the affair was a close call stemming directly from a decision made in a climate of deep distrust between key administration officials and the intelligence community. using recently declassified documents, secondary materials, and interviews with several key participants, the authors weave a story of intra - agency conflict, suspicion, and discord that undermined intelligence - gathering, adversely affected internal postmortems conducted after the crisis peaked, and resulted in keeping congress and the public in the dark about what really happened. we asked barrett, a professor of political science at villanova university, to discuss the actual series of events and what might have happened had the cia not detected soviet missiles on cuba. the actual sequence of events... “ some months after the cuban missile crisis, an angry member of the armed services committee of the house of representatives criticized leaders of the kennedy administration for having let weeks go by in september and early october 1962, without detecting soviet construction of missile sites in cuba. it was an intelligence failure as serious as the u. s. ignorance that preceded the japanese attack on pearl harbor in 1941, he said. secretary of defense robert mcnamara aggressively denied that there had been an american intelligence failure or ineptitude with regard to cuba in late summer 1962. mcnamara and others persuaded most observers the administration ’ s performance in the lead - up to the crisis had been almost flawless, but the legislator was right : the cia had not sent a u - 2 spy aircraft over western cuba for about a six week period. there were varying reasons for this, but the most important was that the kennedy administration did not wish to have a u - 2 “ incident. ” sending that aircraft over cuba raised the possibility that soviet surface - to - air missiles might shoot one down. since it was arguably against international law for the u. s. to send spy aircrafts over another country, should one be shot down, there would probably be the same sort of uproar as happened in may 1960, when the soviet union shot down an american u - 2 flying over its territory. furthermore, most state department and cia authorities did not believe that the ussr would put nuclear - armed missiles into cuba that could strike the u. s


happened in may 1960, when the soviet union shot down an american u - 2 flying over its territory. furthermore, most state department and cia authorities did not believe that the ussr would put nuclear - armed missiles into cuba that could strike the u. s. therefore, the cia was told, in effect, not even to request permission to send u - 2s over western cuba. this, at a time when there were growing numbers of reports from cuban exiles and other sources about suspicious soviet equipment being brought into the country. as we now know, the soviets were constructing missile sites on what cia deputy director richard helms would call “ the business end of cuba, ” i. e., the western end, in the summer / autumn of 1962. fortunately, by mid - october, the cia ’ s director, john mccone, succeeded in persuading president john f. kennedy to authorize one u - 2 flight over that part of cuba and so it was that agency representatives could authoritatively inform jfk on october 16th that the construction was underway. the cia had faced white house and state department resistance for many weeks about this u - 2 matter. " what could have happened... “ what if mccone had not succeeded in persuading the president that the u. s. needed to step up aerial surveillance of cuba in mid - october? what if a few more weeks had passed without that crucial october 14 u - 2 flight and its definitive photography of soviet missile site construction? remember to check out blind over cuba : the photo gap and the missile crisis, which is being published this fall! if mccone had been told “ no ” in the second week of october, perhaps it would have taken more human intelligence, trickling in from cuba, about such soviet activity before the president would have approved a risky u - 2 flight. the problem jfk would have faced then is that there would have been a significant number of operational medium - range missile launch sites. those nuclear - equipped missiles could have hit the southern part of the u. s. meanwhile, the soviets would also have progressed further in construction of intermediate missile sites ; such missiles could have hit most of the continental united states. if jfk had not learned about soviet nuclear - armed missiles until, say, november 1st, what would the u. s. have done? there is no definitive answer to that question, but i think it ’ s fair to say that the president would have been under enormous pressure to authorize — quickly - - a huge u. s. air


if you have ever used the windows copy ( ctrl + c ) to copy objects to the clipboard and then the windows paste ( ctrl + v ) to copy / paste autocad object ( s ), then you know that those clipboard object ( s ) will have the lower left - hand corner of their extents as the base point ( not very precise )... and this always reminds me of some of the graphic editing applets ( e. g. : paint or even the wonderful autocad button editor! ) that have you draw a circle like a rectangle. ( annoying to say the least! ) with autocad you can use the keyboard shortcut of ( ctrl + shft + c ) to pick a base point for your clipboard object ( s ). copybase is the actual command, and then you can paste to a precise point in the destination autocad dwg file using the keyboard shortcut of ( ctrl + shift + v ). this is the pasteblock command or you can also use the pasteorig command if the copybased object ( s ) go in the same exact spot in the receiving dwg file. also it is important to note : if you do use the ctrl + shift + v pasteblock method and want to leave it as a block, autocad will assign a name for the block, which is something like " a $ c11a06afd " or " a $ c1f7a5022 "... either use the rename command, or use explode or xplode, also watch your layers, with regards to the object ( s ) original layers and where this new " block " is being inserted... or where they go if they are exploded vs. xploded. ( i will save that for a whole different post ).


the neighbor squirrel these busy fluffballs have lost their fear of most predators - and they help plant pecan trees. by sheryl smith - rodgers have you ever watched an eastern fox squirrel ( sciurus niger ) bury an acorn or pecan? a nuzzle here, another there, then he hurriedly pushes the leaves and grass over the site before scampering up the closest tree. minutes later, he ' s back with another nut. over the course of three months, that industrious squirrel can bury several thousand pecans. come winter, when food ' s scarce, he ' ll find them again with his excellent sense of smell. some will escape his appetite, though, and sprout into saplings, which is how many native nut trees get planted. eastern fox squirrels - the state ' s most common and wide - ranging squirrel and a popular game animal, too - occur in forests and riparian habitats. they also easily adapt to cities and neighborhoods, where they ' ve lost most of their fear of natural predators. " playing the call of a red - tailed hawk didn ' t phase squirrels on campus, " reports bob mccleery, a wildlife lecturer at texas a & m university, who has studied urban squirrels in college station. " when we played a coyote call in the navasota river bottom, a squirrel immediately flattened itself in the crotch of a tree for a good five minutes. " when agitated, fox squirrels - whose fur closely resembles that of a gray fox - bark and jerk their long, bushy tails, which they use for balance when scampering on utility lines and other high places. tails provide warmth and protection, too. " in the summer, i ' ve seen them lying down with their tails over their heads to block the sun, " mccleery says.


ragtime and blues fused ‘ all that jazz ’ by laura szepesi published : sunday, march 17, 2013, 7 : 09 p. m. updated : monday, march 18, 2013 editor ' s note : thursday marks the 85th birthday of well - known connellsville jazz trombonist harold betters. we salute him with this four - part series, starting today with a brief history of jazz music. in 1979, actor roy scheider brought the life of broadway dancer / director bob fosse to the big screen in the film “ all that jazz. ” “ all ” is the perfect way to describe jazz music. jazz was born around 1900 in new orleans — about the same time as the earliest music recordings became available to the public. it grew out of ragtime, which many sources claim is the first true american music. like jazz, ragtime has southern roots, but was also flavored by the southern midwest. it was popular from the late 1800s to around 1920. it developed in african american communities, a mix of march music ( from composers such as john philip sousa ), black songs and dances including the cakewalk. ragtime : dance on eventually, ragtime spread across the united states via printed sheet music, but its roots were as live dance music in the red light districts of large cities such as st. louis and new orleans. ernest hogan is considered ragtime ' s father. he named it ragtime because of the music ' s lively ragged syncopation. ragtime faded as jazz ' s following grew. however, composers enjoyed major success in ragtime ' s early years. scott joplin ' s 1899 “ maple leaf rag ” was a hit, as was his “ the entertainer, ” which was resurrected as a top 5 hit when it was featured in the 1974 movie “ the sting ” starring robert redford and paul newman. born of ragtime, jazz was also heavily influenced by the blues. blues originated in the late 1800s, but in the deep south. it is an amalgam of negro spirituals, work songs, shouts, chants and narrative lyrics. fused with blues like jazz, the blues comes in many forms : delta, piedmont, jump and chicago blues. its popularity grew after world war ii when electric guitars — rather than acoustic guitars — became popular. by the early 1970s, blues had formed another hybrid : blues rock. while ragtime is jangly and spirited, the blues takes after its name : blue, or melancholy. its name is traced to 1912 when hart


than acoustic guitars — became popular. by the early 1970s, blues had formed another hybrid : blues rock. while ragtime is jangly and spirited, the blues takes after its name : blue, or melancholy. its name is traced to 1912 when hart ward copyrighted the first blues song, “ dallas blues. ” jazz — as a mix of ragtime and blues — has fused into many styles since its emergence. in the 1910s, new orleans jazz was the first to take off. in the 1930s and 1940s, big band swing, kansas city jazz and bebop prevailed. other forms include cool jazz and jazz rock ; today, there ' s even cyber jazz. jazz : always changing the late jazz trombone player j. j. johnson summed jazz up as restless. “ it won ' t stay put... and never will, ” he was quoted as saying, according to various sources. johnson ' s sentiment is heartily endorsed by connellsville jazz trombonist harold betters. betters turns 85 years old this week. he will share decades of his memories about music and growing up in connellsville as his march 21 birthday approaches. laura szepesi is a freelance writer. tuesday : just how did harold betters decide to play the trombone? - uniontown police investigate shooting injury - upper tyrone family helps pet overcome paralysis - several fayette boroughs have contested races - recap of the death of connellsville police officer mccray robb in 1882 - connellsville police officer recognized 131 years after death - fayette county man accused of receiving stolen property, multiple drug offenses - connellsville set to debut model - railroad train in 2014 - connellsville airport will remain open - connellsville mayoral candidate joshua dewitt held for trial in chop shop case - south connellsville man charged in pedestrian accident - connellsville council to make appointments, reappointments you must be signed in to add comments to comment, click the sign in or sign up at the very top of this page. subscribe today! click here for our subscription offers.


welcome to bsa troop 51 based out of waterford, mi. please take a look around and have a great day. how scouting started in the united states one day in 1909 in london, england, an american visitor, william d. boyce, lost his way in a dense fog. he stopped under a street lamp and tried to figure out where he was. a boy approached him and asked if he could be of help. you certainly can, said boyce. he told the boy that he wanted to find a certain business office in the center of the city. i ’ ll take you there, said the boy. when they got to the destination, mr. boyce reached into his pocket for a tip. but the boy stopped him. no thank you, sir. i am a scout. i won ’ t take anything for helping. a scout? and what might that be? asked boyce. the boy told the american about himself and about his brother scouts. boyce became very interested. after finishing his errand, he had the boy take him to the british scouting office. at the office, boyce met lord robert baden - powell, the famous british general who had founded the scouting movement in great britain. boyce was so impressed with what he learned that he decided to bring scouting home with him. on february 8, 1910, boyce and a group of outstanding leaders founded the boy scouts of america. from that day forth, scouts have celebrated february 8, as the birthday of scouting in the united states. what happened to the boy who helped mr. boyce find his way in the fog? no one knows. he had neither asked for money nor given his name, but he will never be forgotten. his good turn helped bring the scouting movement to our country. in the british scout training center at gilwell park, england, scouts from the united states erected a statue of an american buffalo in honor of this unknown scout. one good turn to one man became a good turn to millions of american boys. such is the power of a good turn. hence the scout slogan : do a good turn daily


the diagnosis of trichotillomania ( tm ) is synonymous with the act of recurrently pulling one ’ s own body hair resulting in noticeable thinning or baldness. ( american psychiatric association, diagnostic and statistical manual of mental disorders, 2000, p. 674 ) sites of hair pulling can include any area of the body in which hair is found, but the most common sites are the scalp, eyelashes, eyebrows, and the pubis area. ( kraemer, 1999, p. 298 ) the disorder itself is categorized in the dsm - iv - tr as an “ impulse control disorder not elsewhere classified ” along with disorders like pathological gambling, pyromania, kleptomania, and intermittent explosive disorder. although tm was previously considered to be a rare disorder, more recent research indicates that prevalence rates of tm may be as high as 2 % of the general population. ( kraemer, 1999, p. 298 ) this prevalence rate is significantly higher than the lifetime prevalence rate of. 6 % that is cited as a potential baseline among college students the dsm - iv - tr. ( 4th ed., text rev. ; dsm - iv - tr ; american psychiatric association, 2000, p. 676 ) the condition appears to be more common among women and the period of onset is typically in childhood or adolescence. ( kraemer, 1999, p. 298 ) as is customary with most dsm - iv - tr diagnoses, the act of hair pulling cannot be better accounted for by another mental disorder ( like delusions, for example ) or a general medical condition. like every disorder in the dsm - iv - tr, the disturbance must cause significant distress or impairment in functioning. ( 4th ed., text rev. ; dsm - iv - tr ; american psychiatric association, 2000, p. 675 ) alopecia is a key concept that must be understood in order to complete the differential diagnosis of tm. alopecia is a condition of baldness in the most general sense. ( shiel, jr. & stoppler, 2008, p. 14 ) other medically related causes of alopecia should be considered in the differential diagnosis of tm, especially when working with an individual who deny pulling their hair. the common suspects include male - pattern baldness, discoid lupus erythematosus ( dle ), lichen planopilaris ( also known as acuminatus ), folliculitis


deny pulling their hair. the common suspects include male - pattern baldness, discoid lupus erythematosus ( dle ), lichen planopilaris ( also known as acuminatus ), folliculitis decalvans, pseudopelade of brocq, and alopecia mucinosa ( follicular mucinosis ). ( 4th ed., text rev. ; dsm - iv - tr ; american psychiatric association, 2000, p. 676 ) comprehensive coverage of these medical conditions is beyond the scope of this article – all of the aforementioned confounding variables can be eliminated by a general practitioner. there are a number of idiosyncratic features associated with tm that bear mentioning. although the constellation of features covered here is not sufficient to warrant a diagnosis in isolation, they can aid in the differential diagnosis process. alopecia, regardless of the cause, has been known to lead sufferers to tremendous feats of avoidance so that the hair loss remains undetected. simply avoiding social functions or other events where the individual ( and their attendant hair loss ) might be uncovered is a common occurrence. in cases where individual ’ s focus of attention is on the head or scalp, it is not uncommon for affected individuals to attempt to hide hair loss by adopting complimentary hair styles or wearing other headwear ( e. g., hats, wigs, etc ). these avoidance behaviors will be the target of exposure and response prevention later in this article. in addition to avoidant behavior and elaborate attempts to “ cover it up, ” individuals with tm frequently present with clinically significant difficulty in areas such as self - esteem and mood. comorbidity, or the presence of one or more disorders in the addition to a primary diagnosis, is the rule not the exception in the stereotypical presentation of tm. mood disorders ( like depression ) are the most common ( 65 % ) – anxiety ( 57 % ), chemical use ( 22 % ), and eating disorders ( 20 % ) round out the top four mostly likely candidates for comorbidity. ( kraemer, 1999, p. 298 ) these comorbidity rates are not overly surprising since they parallel prevalence rates across the wider population – perhaps with the notable exception of the high rate of comorbid eating disorders. we can speculate about the source of comorbidity – one possible hypothesis is that a few people who suffer tm also suffer from a persistent cognitive dissonance


perhaps with the notable exception of the high rate of comorbid eating disorders. we can speculate about the source of comorbidity – one possible hypothesis is that a few people who suffer tm also suffer from a persistent cognitive dissonance associated with having happy - go - lucky personality trait which leads them “ let the chips fall where they may. ” they are individuals prone to impulsivity, but they are subdued and controlled the shame, guilt, frustration, fear, rage, and helplessness associated with the social limitations placed on them by the disorder. ( ingram, 2012, p. 269 ) on the topic of personality, surprisingly enough, research suggests that personality disorders do not share significant overlap with tm. this includes borderline personality disorder ( bpd ) despite the fact that bpd is often associated with self - harming behavior. ( kraemer, 1999, p. 299 ) differentiating tm from obsessive - compulsive disorder ( ocd ) can be challenging in some cases. tm is similar to ocd because there is a “ sense of gratification ” or “ relief ” when pulling the hair out. unlike individuals with ocd, individuals with tm do not perform their compulsions in direct response to an obsession and / or according to rules that must be rigidly adhered to. ( 4th ed., text rev. ; dsm - iv - tr ; american psychiatric association, 2000, p. 676 ) there are, however, observed similarities between ocd and tm regarding phenomenology, neurological test performance, response to ssri ’ s, and contributing elements of familial and / or genetic factors. ( kraemer, 1999, p. 299 ) due to the large genetic component contributions of both disorders, obtaining a family history ( vis - a - vis a detailed genogram ) is highly recommended. the comprehensive genogram covering all mental illness can be helpful in the discovery the comorbid conditions identified above as well. there is some suggestion that knowledge of events associated with onset is “ intriguing, but unnecessary for successful treatment. ” ( kraemer, 1999, p. 299 ) i call shenanigans. there is a significant connection between the onset of tm and the patient enduring loss, perceived loss, and / or trauma. time is well spent exploring the specific environmental stressors that precipitated the disorder. although ignoring circumstances surrounding onset might be prudent when employing strict behavioral treatment paradigms,


and the patient enduring loss, perceived loss, and / or trauma. time is well spent exploring the specific environmental stressors that precipitated the disorder. although ignoring circumstances surrounding onset might be prudent when employing strict behavioral treatment paradigms, it seems like a terrible waste of time to endure suffering without identifying some underlying meaning or purpose that would otherwise be missed if we overlook onset specifics. “ everything can be taken from a man but one thing : the last of human freedoms – to choose one ’ s attitude in any given set of circumstances, to choose one ’ s own way. ” ( frankl, 1997, p. 86 ) if we acknowledge that all behavior is purposeful, then we must know and understand the circumstances around onset if we will ever understand the purpose of said behavior. i liken this to a difference in professional opinion and personal preference because either position can be reasonably justified, but in the end the patient should make the ultimate decision about whether or not to explore onset contributions vis - a - vis “ imagery dialogue ” or a similar technique. ( young, klosko, & weishaar, 2003, p. 123 ) if such imagery techniques are unsuccessful or undesired by the client, a psychodynamic conversation between “ internal parts of oneself ” can add clarity to the persistent inability of the client to delay gratification. ( ingram, 2012, p. 292 ) such explorations are likely to be time consuming, comparatively speaking, and should not be explored with patients who are bound by strict eap requirements or managed care restrictions on the type and length of treatment. comorbid developmental disabilities and cognitive deficits may preclude this existential exploration. i employ the exploration of existential issues of origin in the interest of increasing treatment motivation, promoting adherence, enhancing the therapeutic milieu, and thwarting subsequent lapses by anchoring cognitive dissonance to a concrete event. tm represents a behavioral manifestation of a fixed action patterns ( faps ) that is rigid, consistent, and predicable. faps are generally thought to have evolved from our most primal instincts as animals – they are believed to contain fundamental behavioral ‘ switches ’ that enhance the survivability of the human species. ( lambert & kinsley, 2011, p. 232 ) the nature of faps that leads some researchers to draw parallels to tm is that faps appear to be qualitatively “ ballistic. ” it ’ s an “ all or nothing ” reaction that is comparable to an action potential


. 232 ) the nature of faps that leads some researchers to draw parallels to tm is that faps appear to be qualitatively “ ballistic. ” it ’ s an “ all or nothing ” reaction that is comparable to an action potential traveling down the axon of a neuron. once they are triggered they are very difficult to suppress and may have a tendency to “ kindle ” other effects. ( lambert & kinsley, 2011, p. 233 ) there are some unique considerations when it comes to assessing a new patient with tm. because chewing on or ingesting the hair is reported in nearly half of tm cases, the attending clinician should always inquire about oral manipulation and associated gastrointestinal pain associated with a connected hair mass in the stomach or bowel ( trichobezoar ). motivation for change should be assessed and measured because behavioral interventions inherently require a great deal of effort. family and social systems should not be ignored since family dynamics can exacerbate symptomatlogy vis - a - vis pressure to change ( negative reinforcement ), excessive attention ( positive reinforcement ), or both. ( kraemer, 1999, p. 299 ) what remains to be seen is the role of stress in the process of “ triggering ” a tm episode. some individuals experience an “ itch like ” sensation as a physical antecedent that remits once the hair is pulled. this “ itch like ” sensation is far from universal. some clinicians and researchers believe that the abnormal grooming behavior found in tm is “ elicited in response to stress ” with the necessary but not sufficient condition of “ limited options for motoric behavior and tension release. ” ( kraemer, 1999, p. 299 ) although this stress hypothesis may materialize as a tenable hypothesis in some cases, it ’ s by no means typical. most people diagnosed with tm report that the act of pulling typically occurs during affective states of relaxation and distraction. most individuals whom suffer from tm do not report clinically significant levels of anxiety as the “ trigger ” of bouts of hair pulling. we could attribute this to an absence of insight regarding anxiety related triggers or, perhaps anxiety simply does not play a significant role in the onset and maintenance of hair pulling episodes. regardless of the factors that trigger episodes, a comprehensive biopsychosocial assessment that includes environmental stressors ( past, present and anticipated ) should be explored. the options for treatment of tm are limited at best


and maintenance of hair pulling episodes. regardless of the factors that trigger episodes, a comprehensive biopsychosocial assessment that includes environmental stressors ( past, present and anticipated ) should be explored. the options for treatment of tm are limited at best. ssris have demonstrated some potential in the treatment of tm, but more research is needed before we can consider ssris as a legitimate first - line treatment. ssris are worth a shot as an adjunct treatment in cases of chronic, refractory, or treatment resistant tm. i would consider recommending a referral to a psychiatrist ( not a general practitioner ) for a medication review due in part to the favorable risk profile of the most recent round of ssris. given the high rate of comorbidity with mood and anxiety disorders – if either is anxiety or depression are comorbid, ssris will likely be recommended regardless. killing two birds with one stone is the order of the day, but be mindful that some medication can interfere with certain treatment techniques like imaginal or in vivo exposure. ( ledley, marx, & heimberg, 2010, p. 141 ) additional research is needed before anxiolytic medications can be recommended in the absence of comorbid anxiety disorders ( especially with children ). hypnosis and hypnotic suggestion in combination with other behavioral interventions may be helpful for some individuals, but i don ’ t know enough about it at this time to recommend it. call me skeptical, or ignorant, but i prefer to save the parlor tricks for the circus … habit reversal is no parlor trick. my goal isn ’ t to heal the patient ; that would create a level of dependence i am not comfortable with … my goal is to teach clients how to heal themselves. okay, but how? the combination of competing response training, awareness / mindfulness training, relaxation training, contingency management, cognitive restructuring, and generalization training is the best hope for someone who seeks some relief from tm. collectively i will refer to this collection of techniques as habit reversal. competing response training is employed in direct response to hair pulling or in situations where hair pulling might be likely. in the absence of “ internal restraints to impulsive behavior, ” artificial circumstances are created by identifying substitute behaviors that are totally incompatible with pulling hair. ( ingram, 2012, p. 292 ) just like a compulsive gambling addict isn ’ t in any danger if spends all his money on rent, someone with tm is much less likely to pull hair if they are doing


pulling hair. ( ingram, 2012, p. 292 ) just like a compulsive gambling addict isn ’ t in any danger if spends all his money on rent, someone with tm is much less likely to pull hair if they are doing something else with their hands. antecedents, or triggers, are sometimes referred to as discriminative stimuli. ( ingram, 2012, p. 230 ) “ we sense objects in a certain way because of our application of priori intuitions … ” ( pirsig, 1999, p. 133 ) altering the underlying assumptions entrenched in maladaptive priori intuitions is the core purpose of awareness and mindfulness training. “ there is a lack of constructive self - talk mediating between the trigger event and the behavior. the therapist helps the client build intervening self - messages : slow down and think it over ; think about the consequences. ” ( ingram, 2012, p. 221 ) the connection to contingency management should be self evident. utilizing a customized self - monitoring record, the patient begins to acquire the necessary insight to “ spot ” maladaptive self talk. “ spotting ” is not a new or novel concept – it is central component of abraham low ’ s revolutionary self help system recovery international. ( abraham low self - help systems, n. d. ) the customized self - monitoring record should invariably include various data elements such as precursors, length of episode, number of hairs pulled, and a subjective unit of distress representing the level of “ urge ” or desire to pull hair. ( kraemer, 1999 ) the act of recording behavior ( even in the absence of other techniques ) is likely to produce significant reductions in tm symptomatlogy. ( persons, 2008, p. 182 - 201 ) perhaps more importantly, associated activities, thoughts, and emotions that may be contributing to the urge to pull should be codified. ( kraemer, 1999, p. 300 ) in session, this record can be reviewed and subsequently tied to “ high risk circumstances ” and “ priori intuitions ” involving constructs such as anger, frustration, depression, and boredom. relaxation training is a critical component if we subscribe to the “ kindling ” hypothesis explained previously. relaxation is intended to reduce the urges that inevitably trigger the habit. examples abound, but diaphragmatic breathing, progressive relaxation, and visualization are all techniques that can be employed in isolation or in conjunction with each other. contingency management is inexorably tied


urges that inevitably trigger the habit. examples abound, but diaphragmatic breathing, progressive relaxation, and visualization are all techniques that can be employed in isolation or in conjunction with each other. contingency management is inexorably tied to the existential anchor of cognitive dissonance described above. my emphasis on this element is where my approach might differ from some other clinicians. “ you are free to do whatever you want, but you are responsible for the consequences of everything that you do. ” ( ingram, 2012, p. 270 ) this might include the client writing down sources of embarrassment, advantages of controlling the symptomatlogy of tm, etc. ( kraemer, 1999 ) the moment someone with pyromania decides that no fire worth being imprisoned, they will stop starting fires. the same holds true with someone who acknowledges the consequences of pulling their hair. how do we define success? once habit reversal is successfully accomplished in one setting or situation, the client needs to be taught how to generalize that skill to other contexts. a hierarchical ranking of anxiety provoking situations can be helpful in this process since self - paced graduated exposure is likely to increase tolerability for the anxious client. ( ingram, 2012, p. 240 ) if skills are acquired, and generalization occurs, we can reasonably expect a significant reduction in tm symptomatlogy. the challenges are significant, cognitive behavioral therapy is much easier said than done. high levels of treatment motivation are required for the behavioral elements, and moderate to high levels of insight are exceptionally helpful for the cognitive elements. in addition, this is an impulse control disorder … impulsivity leads to treatment noncompliance and termination. the combination of all the above, in addition to the fact that tm is generally acknowledged as one of the more persistent and difficult to treat disorders, prevents me from providing any prognosis other than “ this treatment will work as well as the client allows it to work. ” abraham low self - help systems. ( n. d. ). recovery international terms and definitions. retrieved august 2, 2012, from http : / / www. lowselfhelpsystems. org / system / recovery - international - language. asp american psychiatric association. ( 2000 ). diagnostic and statistical manual of mental disorders ( 4th ed., text rev. ). washington, dc : author. frankl, v. e. ( 1997 ). man ’ s search for meaning ( rev. ed. ).


2000 ). diagnostic and statistical manual of mental disorders ( 4th ed., text rev. ). washington, dc : author. frankl, v. e. ( 1997 ). man ’ s search for meaning ( rev. ed. ). new york, ny : pocket books. ingram, b. l. ( 2012 ). clinical case formulations : matching the integrative treatment plan to the client ( 2nd ed. ). hoboken, nj : john wiley & sons. kraemer, p. a. ( 1999 ). the application of habit reversal in treating trichotillomania. psychotherapy : theory, research, practice, training, 36 ( 3 ), 298 - 304. doi : 10. 1037 / h0092314 lambert, k. g., & kinsley, c. h. ( 2011 ). clinical neuroscience : psychopathology and the brain ( 2nd ed. ). new york : oxford university press. ledley, d. r., marx, b. p., & heimberg, r. g. ( 2010 ). making cognitive - behavioral therapy work : clinical process for new practitioners ( 2nd ed. ). new york, ny : guilford press. persons, j. b. ( 2008 ). the case formulation approach to cognitive - behavior therapy. new york, ny : guilford press. pirsig, r. m. ( 1999 ). zen and the art of motorcycle maintenance : an inquiry into values ( 25th anniversary ed. ). new york : quill. shiel, w. c., jr., & stoppler, m. c. ( eds. ). ( 2008 ). webster ’ s new world medical dictionary ( 3rd ed. ). hoboken, nj : wiley publishing. young, j. e., klosko, j. s., & weishaar, m. e. ( 2003 ). schema therapy : a practitioner ’ s guide. new york : guilford press.


science announced that it is taking viewers further inside nasa ' s latest mission to mars with the exclusive world premiere of i. am. mars : reach for the stars tonight, september 19, 2012, at 10 pm et / pt. the special documents the artistic and technical process behind " reach for the stars, " will. i. am ' s newest single that became the first song ever to be broadcast from another planet to earth. in what is being hailed as " the most complex mars mission to date, " nasa ' s curiosity spacecraft successfully landed on the red planet on august 6, 2012. since then the curiosity rover has returned stunning photographs and valuable information about the martian surface that is helping scientists determine if it has the ability to support life. recently, curiosity also returned will. i. am ' s new song " reach for the stars " as - for the first time in history - recorded music was broadcast from a planet to earth. i. am. mars : reach for the stars profiles will. i. am ' s passion for science and his belief in inspiring the next generation of scientists through stem ( science, technology, engineering and math ) education. i. am. mars : reach for the stars also gives viewers a window into his creative process, as well as the recording of the song with a full children ' s choir and orchestra. in addition, viewers also go inside the engineering challenges nasa faced in uploading the song to curiosity, and the hard work required to make the historic 700 million mile interplanetary broadcast a reality. " between mars landing 2012 : the new search for life and i. am. mars : reach for the stars, science is consumed with the bold exploration of the red planet, " said debbie myers, general manager and executive vice president of science. " we hope our viewers are as inspired as we are by the creativity, imagination and daring of both will. i. am and nasa. " i. am. mars will be distributed to schools nationwide through discovery education ' s digital streaming services. science and discovery education will also work with affiliates to promote i. am. mars ' educational resources for use in schools and with community organizations, brining the magic of mars to life.


| ufdc home | | | help | | the florida geological survey digital collection includes historic resources from the florida geological survey ( fgs ). fgs is an office which reports directly to the deputy secretary for land & recreation in the florida department of environmental protection. the mission of the fgs is to collect, interpret, disseminate, store and maintain geologic data, thereby contributing to the responsible use and understanding of florida ’ s natural resources, and to conserve the state of florida ’ s oil and gas resources and minimize environmental impacts from exploration and production operations. historic resources from the florida geological survey digital collection includes historic fgs : for a list of all publications, historic through current, see the fgs website. florida geological survey fossil collection in the florida museum of natural history the florida geological survey fossil vertebrate collection ( fgs ) was started during the 1910s and was originally housed in tallahassee. under the direction of e. h. sellards, herman gunter, and s. j. olsen, the fgs collection was the primary source of fossil vertebrate descriptions from florida until the early 1960s. world - renown paleontologists such as george g. simpson, edwin h. colbert, and henry f. osborn wrote scientific papers about specimens in the fgs collection in addition to sellards and olsen. in 1976 the entire fgs fossil vertebrate collection was transferred to the florida museum of natural history with support from a national science foundation grant. the uf / fgs collection is composed of about 22, 000 specimens assigned to about 10, 000 catalogue numbers, and almost all of them were collected in florida. the majority of specimens in the uf / fgs collection are mammals, followed by reptiles, birds, and a relatively small number of amphibians and fish. although there are some sites that are unique to the uf / fgs collection, many of the sites overlap with holdings in the main uf and uf / pb collections. the major strengths of the uf / fgs collection are historically important samples from the early miocene thomas farm locality, the middle miocene and early pliocene deposits of the bone valley region, polk county, and from the late pleistocene vero locality, indian river county. researchers using the uf / fgs database should be aware that when the catalogue data for the fgs collection was first transferred from the original file cards to a computerized database in the late 1980s, relatively little effort was made to correct or improve entries. the nature of specimen was not


##gs database should be aware that when the catalogue data for the fgs collection was first transferred from the original file cards to a computerized database in the late 1980s, relatively little effort was made to correct or improve entries. the nature of specimen was not indicated on many of the cards, locality information was sometimes vague, and many employed taxonomic names that are no longer in use. while some corrections have subsequently been made to this database, limitations of time and resources have prevented an exhaustive clean - up. also, when sellards left florida for texas in the 1920s, he transferred some, but not all, of the holotypes in the fgs collection that he had named to the usnm collection, smithsonian institution, washington, d. c. united states geological survey water management districts of florida for information about the florida geological survey : dr. jon arthur florida geological survey 903 west tennessee street tallahassee, fl 32304 - 7000 phone : ( 850 ) 488 - 4191 fax : ( 850 ) 488 - 8086 acknowledging or crediting the florida geological survey as creative entity or information source the florida geological survey is providing many of its publications ( state documents ) for the purpose of digitization and internet distribution. if you cite or use portions of these electronic documents, which the florida geological survey ( an office of the florida department of environmental protection ) is making available to the public with the kind assistance of the university of florida ’ s digital library center, we ask that you acknowledge or credit the florida geological survey as the information source : i. e. “ courtesy of the florida department of environmental protection ’ s florida geological survey ” further, since florida geological survey publications were developed using public funds, no proprietary rights may be attached to fgs publications wholly or in part, nor may fgs publications be sold to the u. s. government or the florida state government as part of any procurement of products or services. our publications are disseminated to citizens “ as is " for general public information purposes ; many of them reflect the state of knowledge at the time of their publication and they may or may not have been updated by more recent publications. our electronic documents should not be altered or manipulated ( largely or in part ) and then republished or reposted on websites for commercial resale. fgs publications committee


welcome to jane addams hull - house museum the jane addams hull - house museum serves as a dynamic memorial to social reformer jane addams, the first american woman to receive the nobel peace prize, and her colleagues whose work changed the lives of their immigrant neighbors as well as national and international public policy. the museum preserves and develops the original hull - house site for the interpretation and continuation of the historic settlement house vision, linking research, education, and social engagement the museum is located in two of the original settlement house buildings - the hull home, a national historic landmark, and the residents ' dining hall, a beautiful arts and crafts building that has welcomed some of the world ' s most important thinkers, artists and activists. the museum and its many vibrant programs make connections between the work of hull - house residents and important contemporary social issues. founded in 1889 as a social settlement, hull - house played a vital role in redefining american democracy in the modern age. addams and the residents of hull - house helped pass critical legislation and influenced public policy on public health and education, free speech, fair labor practices, immigrants ’ rights, recreation and public space, arts, and philanthropy. hull - house has long been a center of chicago ’ s political and cultural life, establishing chicago ’ s first public playground and public art gallery, helping to desegregate the chicago public schools, and influencing philanthropy and culture.


introduction to principles of chemistry and fundamentals of inorganic and biochemistry. structure and chemistry of carbohydrates, lipids, proteins, biochemistry of enzymes, metabolism, body fluids and radiation effects. on - line materials includes the course syllabus, copies of the lecture slides and animations, interactive periodic table, chapter summaries and practice exams. this course is targeted towards health science majors. introduction to principles of chemistry. this course is targeted towards chemistry majors. laboratory experiments to develop techniques in organic chemistry and illustrate principles. on - line materials include step - by - step prelabs for many of the experiments that students will be conducting. theoretical principles of quantitative and instrumental analysis. emphasis is placed on newer analytical tools and equipment. intermediate level course. includes a discussion of the structure, function and metabolism of proteins, carbohydrates and lipids. in addition, there is a review of enzymes, dna and rna. this course stresses theory and application of modern chromatographic methods. on - line materials include the course syllabus, copies of course lecture slides and animations. a ' short course ' covering the use of a mass spectrometer as a gc detector. basic instrumentation, data treatment and spectral interpretation methods will be discussed. on - line materials include copies of course lecture slides and tables to assist in the interpretation of mass spectra. coverage of statistical methods in analytical chemistry. course includes basic statistics, experimental design, modeling, exploratory data analysis and other multivariate techniques. on - line materials include the course syllabus, homework problems and copies of the lecture slides. a survey of the basic equipment, data and methodology of analytical methods that rely on radioisotopic materials. on - line materials include the course syllabus, homework problems. copies of the lecture slides and animations. why i missed the exam


now that we ’ ve said a lot about individual operators on vector spaces, i want to go back and consider some other sorts of structures we can put on the space itself. foremost among these is the idea of a bilinear form. this is really nothing but a bilinear function to the base field :. of course, this means that it ’ s equivalent to a linear function from the tensor square :. instead of writing this as a function, we will often use a slightly different notation. we write a bracket, or sometimes, if we need to specify which of multiple different inner products under consideration. another viewpoint comes from recognizing that we ’ ve got a duality for vector spaces. this lets us rewrite our bilinear form as a linear transformation. we can view this as saying that once we pick one of the vectors, the bilinear form reduces to a linear functional, which is a vector in the dual space. or we could focus on the other slot and define. we know that the dual space of a finite - dimensional vector space has the same dimension as the space itself, which raises the possibility that or is an isomorphism from to. if either one is, then both are, and we say that the bilinear form is nondegenerate. we can also note that there is a symmetry on the category of vector spaces. that is, we have a linear transformation defined by. this makes it natural to ask what effect this has on our form. two obvious possibilities are that and that. in the first case we ’ ll call the bilinear form “ symmetric ”, and in the second we ’ ll call it “ antisymmetric ”. in terms of the maps and, we see that composing with the symmetry swaps the roles of these two functions. for symmetric bilinear forms,, while for antisymmetric bilinear forms we have. this leads us to consider nondegenerate bilinear forms a little more. if is an isomorphism it has an inverse. then we can form the composite. if is symmetric then this composition is the identity transformation on. on the other hand, if is antisymmetric then this composition is the negative of the identity transformation. thus, the composite transformation measures how much the bilinear transformation diverges from symmetry. accordingly, we call it the asymmetry of the form. finally, if we ’ re working over a finite - dimensional vector space we can pick a basis for, and get a matrix for.


the gram - schmidt process now that we have a real or complex inner product, we have notions of length and angle. this lets us define what it means for a collection of vectors to be “ orthonormal ” : each pair of distinct vectors is perpendicular, and each vector has unit length. in formulas, we say that the collection is orthonormal if. these can be useful things to have, but how do we get our hands on them? it turns out that if we have a linearly independent collection of vectors then we can come up with an orthonormal collection spanning the same subspace of. even better, we can pick it so that the first vectors span the same subspace as. the method goes back to laplace and cauchy, but gets its name from jørgen gram and erhard schmidt. we proceed by induction on the number of vectors in the collection. if, then we simply set this “ normalizes ” the vector to have unit length, but doesn ’ t change its direction. it spans the same one - dimensional subspace, and since it ’ s alone it forms an orthonormal collection. now, lets assume the procedure works for collections of size and start out with a linearly independent collection of vectors. first, we can orthonormalize the first vectors using our inductive hypothesis. this gives a collection which spans the same subspace as ( and so on down, as noted above ). but isn ’ t in the subspace spanned by the first vectors ( or else the original collection wouldn ’ t have been linearly independent ). so it points at least somewhat in a new direction. to find this new direction, we define this vector will be orthogonal to all the vectors from to, since for any such we can check where we use the orthonormality of the collection to show that most of these inner products come out to be zero. so we ’ ve got a vector orthogonal to all the ones we collected so far, but it might not have unit length. so we normalize it : and we ’ re done.


sarin was developed in 1938 in germany as a pesticide. its name is derived from the names of the chemists involved in its creation : schrader, ambros, rudriger and van der linde. sarin is a colorless non - persistent liquid. the vapor is slightly heavier than air, so it hovers close to the ground. under wet and humid weather conditions, sarin degrades swiftly, but as the temperature rises up to a certain point, sarin ’ s lethal duration increases, despite the humidity. sarin is a lethal cholinesterase inhibitor. doses which are potentially life threatening may be only slightly larger than those producing least effects. signs and symptoms overexposure may occur within minutes or hours, depending upon the dose. they include : miosis ( constriction of pupils ) and visual effects, headaches and pressure sensation, runny nose and nasal congestion, salivation, tightness in the chest, nausea, vomiting, giddiness, anxiety, difficulty in thinking, difficulty sleeping, nightmares, muscle twitches, tremors, weakness, abdominal cramps, diarrhea, involuntary urination and defecation, with severe exposure symptoms progressing to convulsions and respiratory failure. breath until respiratory protective mask is donned. if severe signs of agent exposure appear ( chest tightens, pupil constriction, in coordination, etc. ), immediately administer, in rapid succession, all three nerve agent antidote kit ( s ), mark i injectors ( or atropine if directed by a physician ). injections using the mark i kit injectors may be repeated at 5 to 20 minute intervals if signs and symptoms are progressing until three series of injections have been administered. no more injections will be given unless directed by medical personnel. in addition, a record will be maintained of all injections given. if breathing has stopped, give artificial respiration. mouth - to - mouth resuscitation should be used when mask - bag or oxygen delivery systems are not available. do not use mouth - to - mouth resuscitation when facial contamination exists. if breathing is difficult, administer oxygen. seek medical attention immediately. contact : immediately flush eyes with water for 10 - 15 minutes, then don respiratory protective mask. although miosis ( pinpointing of the pupils ) may be an early sign of agent exposure, an injection will not be administered when miosis is the only sign present. instead, the individual will be taken immediately


interagency coordinating council " the mission of the utah interagency coordinating council for infants and toddlers with special needs is to assure that each infant and young child with special needs will have the opportunity to achieve optimal health and development within the context of the family. " introduction to icc : interagency coordinating council for infants and toddlers with disabilities and their families what is early intervention? baby watch early intervention is a statewide, comprehensive, coordinated, interagency, multidisciplinary system, which provides early intervention services to infants and toddlers, younger than three years of age, with developmental delay or disability, and their families. early intervention is the " baby " piece of special education. the program is authorized through the individuals with disabilities act ( idea ), part c, ( early intervention program for infants and toddlers with disabilities ). in 1987, utah ' s governor designated the department of health ( doh ) as the " lead agency " for the early intervention program. utah was one of the very first states in the nation to fully implement its early intervention program after securing the approval of the state legislature. at present, there are 16 early intervention programs that serve more than 2, 000 children per month in the state. it is anticipated that the demand for these services will continually increase. what is an interagency coordinating council ( icc )? the creation of an icc was established with the passage of federal law p. l. 99 - 457 in october 1986. developers of the legislation recognized the need for a group outside of the lead agency to " advise and assist " in the development of such a system. the independent nature of the icc is one feature that gives the group the potential for making a contribution to the development of the service system. another feature of the regulations is the multidisciplinary and the multi - constituency representation on the icc. by specifying what types of members should be included on the icc, the legislation enables states to bring together consumer, clinical, political, and administrative communities. this merging of a variety of communities facilitates the building of bridges between the involved agencies. in addition, the committee has provided a broader vision of the service system based upon the participation and contributions of all relevant providers and consumers. the icc, a body required by statute to be appointed by each state ' s governor, is to be an important participant in the development of a well - coordinated service system ( federal interagency coordinating council, june, 1989 ). each state icc determines, in conjunction with the lead agency, the


appointed by each state ' s governor, is to be an important participant in the development of a well - coordinated service system ( federal interagency coordinating council, june, 1989 ). each state icc determines, in conjunction with the lead agency, the nature of the roles and tasks it chooses to perform at various policy stages. the utah icc is an interagency group whose membership represents the statewide early childhood services community. it is comprised of up to 25 members. the purpose of the utah icc is to advise and assist the lead agency in the division of community and family health services, bureau of children with special health care needs in the udoh. much of the work of the icc is accomplished in standing committees and ad hoc task force meetings that perform long range planning, study specific issues and make appropriate actions. a member of the icc chairs each committee. what role does the icc play? the council functions as a planning body at the systems level and advocates for children birth to three years of age and their families with or at - risk for a developmental disability. the council acts in three major roles : ( 1 ) advisor : providing advice to the lead agency, governor and the state legislature on issues related to the development of a coordinated system of early intervention services for children with or at - risk for a developmental disability and their families. the federal law defines the council membership and the program in order to give it a unique view of the " service systems ". the parent component of the council gives it a perspective which may be different from that presented by state agencies which are represented on the council. the council can use its special vantage point to be recognized as a source of information for the lead agency, governor, and legislators, as well as other key decision makers in the state. ( 2 ) negotiator : working as an advocate to encourage a particular course of action by the state. a major activity of the council is to " review and comment on the annual state plan for services for children birth to three years " as part of its overall responsibility to assess the service system as it exists in the state. this information as well as interagency coordination is another important goal of the program and puts the council in a position to be effective in making changes in how services are provided in the state. with agency and provider representatives on the council, communication can more easily be effected and gaps between agencies can hopefully be bridged. ( 3 ) capacity builder : enhancing the ability of the overall service system to address service needs. in this role, the council works


on august 9, 2011, the canadian ice service ( cis ) reported that the petermann ice island - a ( pii - a ) appeared to be grounded off the east coast of newfoundland, east of the city of st. anthony. the moderate resolution imaging spectroradiometer ( modis ) on nasa ’ s terra satellite captured this natural - color image of the ice island and its surroundings on august 14, 2011. clouds hide much of the region, and white lines delineate coasts and borders. pii - a appears as an irregularly shaped white body east of st. anthony. what look like small fragments of ice appear immediately west and north of the ice island. the cis had reported for weeks that the ice island was losing mass due to melting and calving, so a continued loss of ice is consistent with cis reports. pii - a is a remnant of a much larger ice island that calved off the petermann glacier in northwestern greenland on august 5, 2010. over the course of the following year, that ice island fragmented into smaller pieces, which continued drifting. other fragments of the original ice island were in baffin bay and lancaster sound as of august 9, according to the cis. - canadian ice service ( 2011, august 9 ). petermann ice island updates. accessed august 15, 2011.


the press release doesn ’ t contain any pictures, and really doesn ’ t do this new web tool justice, so i ’ ve added some screencaps. in a nutshell, the new iswa site lets you arrange graphical packages of solar images and plots oncsreen for simultaneous evaluation. stuff that had been scattered over several solar related websites is now in one interface. pretty cool. – anthony when nasa ’ s satellite operators need accurate, real - time space - weather information, they turn to the community coordinated modeling center ( ccmc ) of the space weather laboratory at nasa ’ s goddard space flight center in greenbelt, md. the ccmc ’ s newest and most advanced space - weather science tool is the integrated space weather analysis ( iswa ) system. the iswa is a robust, integrated system provides information about space weather conditions past, present, and future and, unlike many other programs currently in use, has an interface that the user can customize to suit a unique set of data requirements. “ the iswa space - weather data analysis system offers a unique level of customization and flexibility to maintain, modify, and add new tools and data products as they become available, ” says marlo maddox, iswa system chief developer at nasa goddard. iswa draws together information about conditions from the sun to the boundary of the sun ’ s influence, known as the heliosphere. the iswa systems digests information from spacecraft including the national oceanic and atmospheric administration ’ s ( noaa ) geostationary operational environmental satellites ( goes ), nasa ’ s solar terrestrial relations observatory ( stereo ), the joint european space agency and nasa mission solar and heliospheric observatory ( soho ), and nasa ’ s advanced composition explorer ( ace ). citizen scientists and science enthusiasts can also use the data, models, and tools of the iswa system. similar to the way in which armchair astronomers have used soho data to discover comets, enthusiasts will find the iswa system a wonderful resource for increasing their familiarity with the concept of space weather. “ we are continuously evolving the iswa system, and we hope that it will benefit not only nasa satellite operators, but also that it may also help space - weather forecasting at other agencies such as the air force weather agency and noaa, ” says michael hesse, chief of the space weather laboratory at nasa goddard. space - weather information tends to be scattered over various web sites. nasa goddard space physicist antti pulkkinen says the iswa system represents “ the most comprehensive single interface


” says michael hesse, chief of the space weather laboratory at nasa goddard. space - weather information tends to be scattered over various web sites. nasa goddard space physicist antti pulkkinen says the iswa system represents “ the most comprehensive single interface for general space - weather - related information, ” providing data on past and current space - weather events. the system allows the user to configure or design custom displays of the information. the system compiles data about conditions on the sun, in earth ’ s magnetosphere — the protective magnetic field that envelops our planet — and down to earth ’ s surface. it provides a user interface to provide nasa ’ s satellite operators and with a real - time view of space weather. in addition to nasa, the iswa system is used by the air force weather agency. access to space - weather information that combines data from state - of - the - art space - weather models with concurrent observations of the space environment provides a powerful tool for users to obtain a personalized “ quick look ” at space - weather information, detailed insight into space - weather conditions, as well as tools for historical analysis of the space - weather ’ s impact. development of the iswa system has been a joint activity between the office of the chief engineer at nasa headquarters and the applied engineering and technology directorate and the science and exploration directorate at nasa goddard. the iswa system is located at nasa goddard. the community coordinated modeling center is funded by the heliophysics division in the science mission directorate at nasa headquarters, and the national science foundation. layout selector tool :


by john carter when abraham lincoln died from an assassin ’ s bullet on april 15, 1865, edwin stanton remarked to those gathered around his bedside, “ now he belongs to the ages. ” one of the meanings implied in stanton ’ s famous statement is that lincoln would not only be remembered as an iconic figure of the past, but that his spirit would also play a significant role in ages to come. the oscar - nominated movie “ lincoln, ” which chronicles the struggle to pass the 13th amendment abolishing slavery, has turned our attention again to lincoln ’ s legacy and his relevance amid our nation ’ s present divisions and growing pains. here is some of the wit and wisdom of abraham lincoln worth pondering : “ as for being president, i feel like the man who was tarred and feathered and ridden out of town on a rail. to the man who asked him how he liked it, he said, ‘ if it wasn ’ t for the honor of the thing, i ’ d rather walk. ’ ” “ i desire so to conduct the affairs of this administration that if at the end, when i come to lay down the reins of power, i have lost every other friend on earth, i shall at least have one friend left, and that friend shall be down inside of me. ” “ should my administration prove to be a very wicked one, or what is more probable, a very foolish one, if you the people are true to yourselves and the constitution, there is but little harm i can do, thank god. ” “ bad promises are better broken than kept. ” “ i am not at all concerned that the lord is on our side in this great struggle, for i know that the lord is always on the side of the right ; but it is my constant anxiety and prayer that i and this nation may be on the lord ’ s side. ” “ i have never had a feeling, politically, that did not spring from the sentiments embodied in the declaration of independence. ” “ those who deny freedom to others deserve it not for themselves ; and, under a just god, cannot long retain it. ” “ as i would not be a slave, so i would not be a master. this expresses my idea of democracy. ” “ the probability that we may fail in the struggle ought not to deter us from the support of a cause we believe to be just. ” “ the true rule, in determining to embrace or reject anything, is not whether it have any evil in it, but whether it have more evil than good.


ought not to deter us from the support of a cause we believe to be just. ” “ the true rule, in determining to embrace or reject anything, is not whether it have any evil in it, but whether it have more evil than good. there are few things wholly evil or wholly good. ” “ some of our generals complain that i impair discipline and subordination in the army by my pardons and respites, but it makes me rested, after a hard day ’ s work, if i can find some good excuse for saving a man ’ s life, and i go to bed happy as i think how joyful the signing of my name will make him ( a deserter ) and his family. ” “ i have been driven many times to my knees by the overwhelming conviction that i had nowhere else to go. ” in addition, lincoln ’ s gettysburg address and his second inaugural speech are ever relevant. and you may wish to add your own favorites to these. paul ’ s advice to us in philippians 4 : 8 is to “ fill your minds with those things that are good and deserve praise : things that are true, noble, right, pure, lovely, and honorable. ” as we celebrate his birthday on the 12th, lincoln ’ s words more than meet this standard! john carter is a weatherford resident whose column, “ notes from the journey, ” is published weekly in the weatherford democrat.


taking every precaution japan takes measures to prevent sars ( june 9, 2003 ) as severe acute respiratory syndrome ( sars ), a new type of pneumonia, rages in wide areas of asia and other places, the japanese government has been busy taking measures to prevent an outbreak from occurring in japan. the government has urged people to take caution in traveling to affected areas, and it has been making every effort to prevent sars from entering japan. in addition, work is progressing on a system in which medical institutions, national and local governments, and corporations will act together to prevent the spread of sars in the event of an outbreak in japan. as a result of these efforts, as of june 9, there have been no confirmed or probable cases of sars in japan. | medical staff practice using an isolator. ( jiji ) plans already developed for dealing with patients on may 1 the government brought the heads of the relevant ministries and agencies together for a first - ever meeting devoted to sars in order to decide what measures should be taken in the event that someone in japan is found to be infected with the virus. the group decided to call on people returning from china to stay at home for 10 days, which is believed to be the incubation period for the disease. taking this into consideration, the ministry of health, labor, and welfare made plans for taking action in the event of an outbreak. it decided to give local governments the authority to direct people believed likely to be infected, or " probable patients, " to hospitalize themselves. in the event that a patient refuses, the local governments are empowered to forcibly hospitalize the person. local governments are readying themselves to accept patients. according to a survey conducted by the nihon keizai shimbun in early may, all of the nation ' s 47 prefectures had already completed action plans spelling out what measures would be taken in the event of an outbreak. in addition, some 250 medical institutions around the country have made such preparations as setting up " negative air - pressure rooms " to prevent the virus from spreading within the hospital or to the outside. local governments in such places as kitakyushu city, hokkaido, and mie prefecture have been purchasing capsules called isolators to be used when suspected sars patients are moved, and they have conducted drills on how to use them with volunteers playing the role of patients. in may a foreign traveler who had been to japan was found to be infected with sars. when this was discovered, the government and local


patients are moved, and they have conducted drills on how to use them with volunteers playing the role of patients. in may a foreign traveler who had been to japan was found to be infected with sars. when this was discovered, the government and local authorities quickly implemented emergency measures, as a result of which no secondary infections occurred. according to a survey conducted by the asahi shimbun, 28 local governments out of the 47 prefectures and 13 major cities in japan, nearly half the total, were rethinking their plans to cope with a potential sars outbreak in light of this news. fukushima prefecture decided to check whether visitors from abroad have come from an area to which the world health organization recommends postponing travel. it will also make use of the local hotels association to determine the previous whereabouts of such guests. kagawa prefecture, meanwhile, which had previously only planned for people who had come in close contact with sars patients, defined as having been within 2 meters, has created an action plan for checking on people who have had even a low possibility of coming in contact with a carrier. public and private sectors taking action the japanese government is stepping up its efforts to take rapid, nationwide measures to prevent sars infection. the ministry of health, labor, and welfare has accelerated revision of the infectious disease law, for example. and while local governments are the first line of defense in tracking the path of infection and following up on people who may have been exposed, the national government will become directly involved in the event that infection spreads outside of a local area. japan is also actively engaged in international cooperation aimed at preventing the spread the private sector has also been taking action to prevent the spread of sars and to reassure travelers. west japan railway co. ( jr west ) has set up a sars - response headquarters and is considering disinfecting affected carriages in the event that an infected person is found to have been onboard a certain train at a certain time. the company also decided to publicly release information on the time and route traveled by any sars patients. orient ferry, which runs a ferry route from shimonoseki to china ' s qingdao, has since late april requested that all passengers and crew fill out health questionnaires, and the company has trained staff for what to do in the event that a passenger falls ill with sars while onboard. the terminal in qingdao, the shuttle bus, and the inside of the ship are all disinfected every day. meanwhile, some companies have taken the step


to do in the event that a passenger falls ill with sars while onboard. the terminal in qingdao, the shuttle bus, and the inside of the ship are all disinfected every day. meanwhile, some companies have taken the step of postponing scheduled business trips to affected areas, and, in response to requests by the government, airlines and ship operators whose vessels operate in japan are distributing health questionnaires to their staff and passengers. japan has avoided sars so far, and there is every reason to be confident that the country will remain free of the disease. even if an outbreak did occur, the concerted efforts of local and national governments and private enterprises to prepare for such an eventuality suggest that it would be handled quickly and efficiently. note : the government ' s " measures upon entry / return to japan " for travelers heading to japan can be found here. ( http : / / www. mofa. go. jp / policy / health _ c / sars / measure0521. html ) related web sites the ministry of health, labor, and welfare world health organization west japan railway co. ( jr west ) copyright ( c ) 2004 web japan. edited by japan echo inc. based on domestic japanese news sources. articles presented here are offered for reference purposes and do not necessarily represent the policy or views of the japanese government. ( november 19, 2002 ) give blood and enjoy ( september 25, 2002 )


protecting your skin and checking it for changes are keys to preventing another melanoma or catching one in an early, treatable stage. exposure to ultraviolet ( uv ) rays produced by the sun increases your risk of melanoma. here ’ s how to protect your skin from the sun ’ s uv rays : - cover your skin with clothing, including a shirt and a hat with a broad brim. - when outside, try to sit in shady areas. - avoid exposing your skin to the sun between 10 : 00 a. m. and 2 : 00 p. m. standard time or 11 : 00 a. m. and 3 : 00 p. m. daylight saving time. - use sunscreens with a sun protection factor ( spf ) of 15 or more on skin that will be exposed to the sun. - wear sunglasses with 99 % or 100 % uv absorption to protect your eyes. - don ' t use sun lamps or tanning booths. check your skin regularly and have someone help you check areas you can ’ t see, such as your back and buttocks, scalp, underneath the breasts of women, and the backs of the legs. if you notice a new, changing or an irregular - looking mole, show it to a doctor experienced in recognizing skin cancers, such as a dermatologist. this may include large, irregular shape with a border that is not smooth and even, more than one color, or irregular texture. your doctor may monitor the mole or recommend removing it contact your doctor if you discover a mole that is new has changed or looks suspicious : large or of irregular shape, color, or texture. - reviewer : brian randall, md - review date : 04 / 2013 - - update date : 04 / 09 / 2013 -


archaeological site of rehman dheri department of archaeology and museums property names are listed in the language in which they have been submitted by the state party. the archaeological site of rehman dheri consists of a rectangular shaped mound covering some twenty two hectares and standing 4. 5 metres above the surrounding field. the final occupational phase of the site is clearly visible on the surface of the mound by eye and also through air photographs. it consisted of a large walled rectangular area with a grid iron network of streets and lanes dividing the settlement into regular blocks. walls delineating individual buildings and street frontages are clearly visible in the early morning dew or after rain and it is also possible to identify the location of a number of small - scale industrial areas within the site marked, as they are, by eroding kilns and scatters of slag. the surface of the mound is littered with thousands of shreds and artefacts, slowly eroding out of room fills. the archaeological sequence at the site of rehman dheri is over 4. 5 metres deep, and covers a sequence of over 1, 400 years beginning at c. 3, 300 bc. the site represents following periods : i c. 3300 - 3850 bc ii c. 2850 - 2500 bc iii c. 2500 - 1900 bc it is generally accept that the settlement received its formal plan in its earliest phases and that subsequent phases replicated the plan over time. although its excavators have cut a number of deep trenches or soundings into the lower levels, the areas exposed have been too limited to undertake a study of change in layout and the spatial distribution of craft activities. it was abandoned at the beginning of the mature indus phase by the middle of the third millennium bc and subsequent activities, greatly reduced, are only recorded on the neighbouring archaeological mound, hisam dheri. the plan of the early harappan settlement is therefore undisturbed by later developments and, as such, represents the most exceptionally preserved example of the beginning of urbanisation in south asia.