Read Bit Research Articles

Using magnetic permeability bits to store information

Steps are described in the development of a new magnetic memory technology, based on states with different magnetic permeability, with the capability to reliably store large amounts of information in a high-density form for decades. The advantages of using the permeability to store information include an insensitivity to accidental exposure to magnetic fields or temperature changes, both of which are known to corrupt memory approaches that rely on remanent magnetization. The high permeability media investigated consists of either films of Metglas 2826 MB (Fe40Ni38Mo4B18) or bilayers of permalloy (Ni78Fe22)/Cu. Regions of films of the high permeability media were converted thermally to low permeability regions by laser or ohmic heating. The permeability of the bits was read by detecting changes of an external 32 Oe probe field using a magnetic tunnel junction 10 μm away from the media. Metglas bits were written with 100 μs laser pulses and arrays of 300 nm diameter bits were read. The high and low permeability bits written using bilayers of permalloy/Cu are not affected by 10 Mrad(Si) of gamma radiation from a 60Co source. An economical route for writing and reading bits as small at 20 nm using a variation of heat assisted magnetic recording is discussed.

THINKING GLOBALLY, SPEAKING LOCALLY

Most Canadians today are familiar with the term “the Global Village”. It is a catch-phrase loaded with positive connotations of unity, familiarity, and humanity on an international scale. Through the modern miracle of electronic networks, most now believe that very personal linkages can be created between just about anyone in any part of the world, regardless of the distance. In short, it means that no-one need be a stranger anymore. However, this is a bit of an incomplete reading of what Marshall McLuhan meant when he originally coined the term. While to the modern urban-dweller a village rustles up images of tire swings, porch doors and the time to sit and talk about the “important things” of life, McLuhan would admonish this perspective as mere nostalgia from people who never actually lived in a village. To him, a village is more claustrophobic, people not as caring as one would think. Instead, it is a place where nosy parkers know your business, the crack in your drapes is a focal point for snoopy neighbors, and a non-stop stream of gossip is purveyed at the local post office. To McLuhan, life in the Global Village was a life lived vicariously. He did not condemn this, but just discussed this facet of the future with a sense of inevitability.

Using a spin torque nano-oscillator to read memory based on the magnetic permeability

We present an archival memory utilizing a spin torque nano-oscillator (STNO) to read bits of data with different magnetic permeability. Basing a magnetic memory on this intrinsic property rather than remanent magnetization reduces the risk of data corruption. The permeability of the bits is read as changes in an applied probe field near the media. These changes in the probe field are measured by detecting microwave frequency shifts in STNOs. The probe field can be tuned over hundreds of Oe to optimize the reading of the media. Using a 400 Oe probe field, we have measured 2% frequency shifts in a STNO near micrometre-sized bits of (1) lithographically-patterned permalloy lines and (2) laser-crystallized Metglas lines. Data from either media was not corrupted by exposure to fields of 6400 Oe and temperatures of 523 K.

Continuing Care for Patients Choosing the Emergency Department as a Site for Primary Care: Feasibility, Benefits, and EMTALA Considerations: Answers to the March 2013 Journal Club Questions

Editor’s Note: You are reading the 32nd installment of Annals of Emergency Medicine Journal Club. This Journal Club refers to the Doran et al article that was published in the March 2013 Annals of Emergency Medicine issue. Information about journal club can be found at http://www.annemergmed.com/ content/journalclub. Readers should recognize that these are suggested answers. We hope they are accurate; we know that they are not comprehensive. There are many other points that could be made about these questions or about the article in general. Questions are rated “novice,” ( ) “intermediate,” ( ) and “advanced ( ) so that individuals planning a journal club can assign the right question to the right student. The “novice” rating does not imply that a novice should be able to spontaneously answer the question. “Novice” means we expect that someone with little background should be able to do a bit of reading, formulate an answer, and teach the material to others. Intermediate and advanced questions also will likely require some reading and research, and that reading will be sufficiently difficult that some background in clinical epidemiology will be helpful in understanding the reading and concepts. We are interested in receiving feedback about this feature. Please e-mail journalclub@acep.org with your comments.

A 0.13 µm 8 Mb Logic-Based Cu$_{\rm x}$Si$_{\rm y}$O ReRAM With Self-Adaptive Operation for Yield Enhancement and Power Reduction

A 0.13 µm 8 Mb ${\rm Cu}_{\rm x}{\rm Si}_{\rm y}{\rm O}$ resistive random access memory (ReRAM) test macro with $20{\rm F}^{2}$ cell size is developed based on logic process for embedded applications. Smart and adaptive write and read assist circuits are proposed to fix yield and power consumption issues arising from large variations in set/reset time and high-temperature cell resistance. Self-adaptive write mode (SAWM) helps increase the ${\rm R}_{\rm off}/{\rm R}_{\rm on}$ window from 8X to 24X at room temperature. The reset bit yield is improved from 61.5% to 100% and the high power consumption is eliminated after the cell switches to ${\rm R}_{\rm on}$ during set. Self-adaptive read mode (SARM) increases read bit yield from 98% to 100% at 125 $^{\circ}{\rm C}$ . The typical access time of the on-pitch voltage sense amplifier (SA) is 21 ns. High bandwidth throughput is supported.

Simon Shepherd, The Cambridge Introduction to Modern British TheatreThe Cambridge Introduction to Modern British Theatre. Simon Shepherd. Cambridge and New York: Cambridge University Press, 2009. Pp. vii+250.

<i>Simon Shepherd</i>, The Cambridge Introduction to Modern British Theatre<i>The Cambridge Introduction to Modern British Theatre</i>. Simon Shepherd. Cambridge and New York: Cambridge University Press, 2009. Pp. vii+250.

Point-of-Care Ultrasonography in Assessing Fluid Responsiveness in Sepsis Patients: Sonographer Characteristics, Noninferential Statistics, and Study Design

F a i t Editor’s Note: You are reading the 29th installment of Annals of Emergency Medicine Journal Club. This Journal Club refers to the article by Haydar et al that was published in the September 2012 Annals of Emergency Medicine issue. Information about Journal Club can be found at http://www.annemergmed.com/content/journalclub. Readers should recognize that these are suggested answers. We hope they are accurate; we know that they are not comprehensive. There are many other points that could be made about these questions or about the article in general. Questions are rated “novice,” ( ) “intermediate,” ( ) and “advanced” ( ) so that individuals planning a journal club can assign the right question to the right student. The “novice” rating does not imply that a novice should be able to spontaneously answer the question. “Novice” means we expect that someone with little background should be able to do a bit of reading, formulate an answer, and teach the material to others. Intermediate and advanced questions also will likely require some reading and research, and that reading will be sufficiently difficult that some background in clinical epidemiology will be helpful in understanding the reading and concepts. We are interested in receiving feedback about this feature. Please e-mail journalclub@acep.org with your comments.

A Tale of Two Steroids

Editor’s Note: You are reading the 23rd installment of Annals of Emergency Medicine Journal Club. The article was published in the August 2011 issue and the questions were published in the September 2011 issue. Information about journal club can be found at http://www.annemergmed.com/ content/journalclub. Readers should recognize that these are suggested answers. We hope they are accurate; we know that they are not comprehensive. There are many other points that could be made about these questions or about the article in general. Questions are rated “novice” ( ), “intermediate” ( ), and “advanced” ( ) so that individuals planning a journal club can assign the right question to the right student. The “novice” rating does not imply that a novice should be able to spontaneously answer the question. “Novice” means we expect that someone with little background should be able to do a bit of reading, formulate an answer, and teach the material to others. Intermediate and advanced questions also will likely require some reading and research, and that reading will be sufficiently difficult that some background in clinical epidemiology will be helpful in understanding the reading and concepts. We are interested in receiving feedback about this feature. Please e-mail journalclub@acep.org with your comments.

To Shock or Not to Shock: That is the Question; Is There an Answer?: Answers to the January 2011 Journal Club Questions

Editor’s Note: You are reading the 19th installment of Annals of Emergency Medicine Journal Club. The questions and the article they are about (Stiell et al. Ann Emerg Med. 2011;57: 13-21) were published in the January 2011 issue. Information about journal club can be found at http://www.annemergmed.com/content/journalclub. Readers should recognize that these are suggested answers. We hope they are accurate; we know that they are not comprehensive. There are many other points that could be made about these questions or about the article in general. Questions are rated “novice,” ( ) “intermediate,” ( ) and “advanced” ( ) so that individuals planning a journal club can assign the right question to the right student. The “novice” rating does not imply that a novice should be able to spontaneously answer the question. “Novice” means we expect that someone with little background should be able to do a bit of reading, formulate an answer, and teach the material to others. Intermediate and advanced questions also will likely require some reading and research, and that reading will be sufficiently difficult that some background in clinical epidemiology will be helpful in understanding the reading and concepts. We are interested in receiving feedback about this feature. Please e-mail journalclub@acep.org with your comments.

The moral dilemma

My business is about behaviour. It is the way that people go about their business, both in the office and outside it, that makes it difficult to keep sensitive – maybe even embarrassing – information safe. I spend a fair bit of time reading and researching a variety of sources, not all directly to do with security, and also observing the people around me. This means that when I am out and about, whether it's going to the local supermarket or catching a plane to another country – or any amount of movement in between – I am always collecting information.

Micro-pages

Power consumption and DRAM latencies are serious concerns in modern chip-multiprocessor (CMP or multi-core) based compute systems. The management of the DRAM row buffer can significantly impact both power consumption and latency. Modern DRAM systems read data from cell arrays and populate a row buffer as large as 8 KB on a memory request. But only a small fraction of these bits are ever returned back to the CPU. This ends up wasting energy and time to read (and subsequently write back) bits which are used rarely. Traditionally, an open-page policy has been used for uni-processor systems and it has worked well because of spatial and temporal locality in the access stream. In future multi-core processors, the possibly independent access streams of each core are interleaved, thus destroying the available locality and significantly under-utilizing the contents of the row buffer. In this work, we attempt to improve row-buffer utilization for future multi-core systems. The schemes presented here are motivated by our observations that a large number of accesses within heavily accessed OS pages are to small, contiguous "chunks" of cache blocks. Thus, the co-location of chunks (from different OS pages) in a row-buffer will improve the overall utilization of the row buffer contents, and consequently reduce memory energy consumption and access time. Such co-location can be achieved in many ways, notably involving a reduction in OS page size and software or hardware assisted migration of data within DRAM. We explore these mechanisms and discuss the trade-offs involved along with energy and performance improvements from each scheme. On average, for applications with room for improvement, our best performing scheme increases performance by 9% (max. 18%) and reduces memory energy consumption by 15% (max. 70%).

Micro-pages

Power consumption and DRAM latencies are serious concerns in modern chip-multiprocessor (CMP or multi-core) based compute systems. The management of the DRAM row buffer can significantly impact both power consumption and latency. Modern DRAM systems read data from cell arrays and populate a row buffer as large as 8 KB on a memory request. But only a small fraction of these bits are ever returned back to the CPU. This ends up wasting energy and time to read (and subsequently write back) bits which are used rarely. Traditionally, an open-page policy has been used for uni-processor systems and it has worked well because of spatial and temporal locality in the access stream. In future multi-core processors, the possibly independent access streams of each core are interleaved, thus destroying the available locality and significantly under-utilizing the contents of the row buffer. In this work, we attempt to improve row-buffer utilization for future multi-core systems. The schemes presented here are motivated by our observations that a large number of accesses within heavily accessed OS pages are to small, contiguous "chunks" of cache blocks. Thus, the co-location of chunks (from different OS pages) in a row-buffer will improve the overall utilization of the row buffer contents, and consequently reduce memory energy consumption and access time. Such co-location can be achieved in many ways, notably involving a reduction in OS page size and software or hardware assisted migration of data within DRAM. We explore these mechanisms and discuss the trade-offs involved along with energy and performance improvements from each scheme. On average, for applications with room for improvement, our best performing scheme increases performance by 9% (max. 18%) and reduces memory energy consumption by 15% (max. 70%).

A comprehensive strategy for contention management in software transactional memory

In Software Transactional Memory (STM), contention management refers to the mechanisms used to ensure forward progress--to avoid livelock and starvation, and to promote throughput and fairness. Unfortunately, most past approaches to contention management were designed for obstruction-free STM frameworks, and impose significant constant-time overheads. Priority-based approaches in particular typically require that reads be visible to all transactions, an expensive property that is not easy to support in most STM systems. In this paper we present a comprehensive strategy for contention management via fair resolution of conflicts in an STM with invisible reads. Our strategy depends on (1) lazy acquisition of ownership, (2) extendable timestamps, and (3) an efficient way to capture both priority and conflicts. We introduce two mechanisms--one using Bloom filters, the other using visible read bits --that implement point (3). These mechanisms unify the notions of conflict resolution, inevitability , and transaction retry . They are orthogonal to the rest of the contention management strategy, and could be used in a wide variety of hardware and software TM systems. Experimental evaluation demonstrates that the overhead of the mechanisms is low, particularly when conflicts are rare, and that our strategy as a whole provides good throughput and fairness, including livelock and starvation freedom, even for challenging workloads.

Risk Prediction With Procalcitonin and Clinical Rules in Community-Acquired Pneumonia: Answers to the July 2008 Journal Club Questions

Editor’s Note: You are reading answers to the fourth installment of Annals of Emergency Medicine Journal Club. The questions and the article they are about (Huang et al. Ann Emerg Med. 2008;52:48-58) were published in the July 2008 issue. We thank Dr. Huang and his colleagues for sharing additional data with us, which we used in answering question 4. Information about journal club can be found at http:// www.annemergmed.com/content/journalclub. Readers should recognize that these are suggested answers. We hope they are accurate; we know that they are not comprehensive. There are many other points that could be made about these questions or about the article in general. Questions are rated “novice,” ( ) “intermediate,” ( ) and “advanced” ( ) so that individuals planning a journal club can assign the right question to the right student. The “novice” rating does not imply that a novice should be able to spontaneously answer the question. “Novice” means we expect that someone with little background should be able to do a bit of reading, formulate an answer, and teach the material to others. Intermediate and advanced questions also will likely require some reading and research, and that reading will be sufficiently difficult that some background in clinical epidemiology will be helpful in understanding the reading and concepts. We are interested in receiving feedback about this feature. Please e-mail journalclub@acep.org with your comments.

Acutely Decompensated Heart Failure in a County Emergency Department: A Double-Blind Randomized Controlled Comparison of Nesiritide Versus Placebo Treatment: Answers to May 2008 Journal Club Questions

Editor’s Note: You are reading answers to the third installment of Annals of Emergency Medicine Journal Club. The questions and the article they are about (Miller et al. Ann Emerg Med. 2008;51:571-578.) were published in the May 2008 issue. Information about journal club can be found at http://www.annemergmed.com/content/ journalclub. Readers should recognize that these are suggested answers. We hope they are accurate; we know that they are not comprehensive. There are many other points that could be made about these questions or about the article in general. Questions are rated “novice,” ( ), “intermediate,” ( ), and “advanced” ( ) so that individuals planning a journal club can assign the right question to the right student. The novice rating does not imply that a novice should be able to spontaneously answer the question. “Novice” means we expect that someone with little background should be able to do a bit of reading, formulate an answer, and teach the material to others. Intermediate and advanced questions also will likely require some reading and research, and that reading will be sufficiently difficult that some background in clinical epidemiology will be helpful in understanding the reading and concepts. We are interested in receiving feedback about this feature. Please e-mail journalclub@acep.org with your comments.

A 45 nm 2-port 8T-SRAM Using Hierarchical Replica Bitline Technique With Immunity From Simultaneous R/W Access Issues

We propose a new 2-port SRAM with a single read bit line (SRBL) eight transistors (8 T) memory cell for a 45 nm system-on-a-chip (SoC). Access time tends to be slower as a fabrication is scaled down because of threshold voltage (Vt) random variations. A divided read bit line scheme with shared local amplifier (DBSA) realizes fast access time without increasing area penalty. We also show an additional important issue of a simultaneous read and write (R/W) access at the same row by using DBSA with the SRBL-8T cell. A rise of the storage node causes misreading. A read end detecting replica circuit (RER) and a local read bit line dummy capacitance (LDC) are introduced to solve this issue. A 128 bit lines - 512 word lines 64 kb 2-port SRAM macro using these schemes was fabricated by a 45 nm bulk CMOS low-standby-power (LSTP) CMOS process technology [1]. The memory cell size is 0.597 mum2. This 2-port SRAM macro achieves 7 times faster access time without misreading.

Characterization of Aberrant Melting Peaks in Unlabeled Probe Assays

An unlabeled probe assay relies on a double-stranded DNA-binding dye to detect and verify target based on amplicon and probe melting. During the development and application of unlabeled probe assays, aberrant melting peaks are sometimes observed that may interfere with assay interpretation. In this report, we investigated the origin of aberrant melting profiles observed in an unlabeled probe assay for exon 10 of the RET gene. It was determined that incomplete 3' blocking of the unlabeled probe allowed polymerase-mediated probe extension resulting in extension products that generated the aberrant melting profiles. This report further examined the blocking ability of the 3' modifications C3 spacer, amino-modified C6, phosphate, inverted dT, and single 3' nucleotide mismatches in unlabeled probe experiments. Although no 3' blocking modifications in these experiments were 100% effective, the amino-modified C6, inverted dT, and C3 spacer provided the best blocking efficiencies (1% or less unblocked), phosphate was not as effective of a block (up to 2% unblocked), and single nucleotide mismatches should be avoided as a 3' blocking modification.

Essay Review: Restroom Reading

Do not do what 1 have just done. Do not try to read this book straight through. Instead, put it on your bedside table and read bits and pieces for 20 min or so each day. Better still, buy a second copy and put it in the guest bedroom or the outhouse or wherever visitors retreat to sev? eral times a day when they come to stay with you. At worst, you will have fascinating discussions over the dinner table. At best, your visitors will escape your teenagers and have spent time with one of the most fascinating minds of our generation. With the death of Ernst Mayr, Edward O. Wilson has inherited the mantle of the world's most distinguished evolutionary biologist. Born in Alabama in 1929, he moved to Harvard for graduate work, staying there for 50 years as he worked up through the ranks of student, fellow, assistant professor until finally he was a university professor. He has won numerous prizes, including two Pulitzer Prizes, for Wilson is not just a great scholar but also a brilliant teacher, a terrific lecturer, and an important public voice. His career has been marked by controversy. His most important book is Sociobiology: The New Synthesis, published in 1975. (As a bibliophile and book collector I dare not tell you what I paid for a first edition, first printing. It was an order of magnitude more than I paid for Richard Lewontin's The Genetic Basis of Evolutionary Change.) After a magnificent survey of the world of animal social behavior, Wilson ended with a chapter on our own species. And all hell let loose. Perhaps expectedly the social scientists did not much like this. Insecure at the best of times, with good reason they feared a take-over by the biologists. Perhaps expectedly the philosophers did not much like this. Very few have come to terms with the fact that being the end result

Writing and reading bits on pre-patterned media

We have written and read back bits on perpendicular pre-patterned media prepared by electron-beam lithography. Using a contact tester equipped with a standard longitudinal head, we are able to write different bit lengths on 100×200 nm2 dots spaced 100 nm apart. These tests demonstrate the role played by the distribution of the coercive fields of the dots during the write process. Signal-to-noise ratios (SNRs) are obtained by numerical analysis and are found to be on the same order of magnitude as in continuous perpendicular media, but remain constant at decreasing bit lengths. This property of the SNR is due to a partial reduction of transition noise. The potential to pattern these media with nanoimprint lithography and their good recording performance make them candidates for ultrahigh density recording.

Forever Juliet: The Life and Letters of Gwen Ffrangcon-Davies 1891-1992 (review)

428Comparative Drama (1986); Cambridge, ed. Alan Nelson (1989); Herefordshire/Worcestershire, ed. David Klausner (1990); Lancashire, ed. David George (1991); Shropshire, ed. J. Alan B. Somerset (1994); Somerset includingBath, ed. James Stokes with Robert J. Alexander (1996); Bristol, ed. Mark C. Pilkinton (1997); Dorset/Cornwall, ed. Rosalind C. Hays and CE. McGee, Sally Joyce and Evelyn S. Newlyn (1999); Sussex, ed. Cameron Lewis (2000); Kent: Diocese of Canterbury, ed. James M, Gibson (2002). MartialRose.ForeverJuliet: TheLifeandLettersofGwenFfrangconDavies 1891-1992. Dereham (UK): LarksPress,2003.Pp.202 + illustrations. £9.50. Outside anglophile dieatrical circles die actress Gwen Ffrangcon-Davies is not well known in the United States. She acted in America only in 1962-1963 as Mrs. Candour in a touringproduction ofSchoolforScandal. She is better known to die British public because of her long and distinguished career and also because of a series of retrospective programs in 1988, the first of which was entided "Forever Juliet," die source for the tide for this engaging book. Martial Rose, recognized for his work on medieval drama and iconography, has chosen to write for a broad audience. The book is not a traditional biography, aldiough Rose traces Ffrangcon-Davies's life and career from its inception (at fourteen she was given Ellen Terry's blessing) until her death. Radier, as he says in the introduction,he has represented"the actress's life dirough die letters and memorabilia ." Neither is die book a mere epistolary collection, but rather a judicious selection from her letters and from the thousands ofletters and notes written to her. The letters not only create a vivid portrait of the actress, but also provide a broad panorama ofthe English theater in die central halfof the twentiedi century . Long quotations from reviews, often from reviewers long forgotten but also from well-known critics like Kenneth Tynan and James Agate, provide a sense ofthetaste ofthe times. Ifmost are congratulatory, Rose cannot be blamed for bias,for he notes that criticisms were fewand sometimes idiosyncratic. James Agate, for example, who generally praised, was acerbic about her "wistful" Lady Macbedi. Aldiough not ascholarly book,ForeverJulietwas clearlywritten bya scholar faced widi die task of reading and organizing material in over 2,000 letters written between die 1880s and 1992, not to mention scrapbooks, programs, photos, and tapes. (Anyone who has visited Ellen Terry's house at Small Hythe will appreciate the collecting proclivity of actresses.) The minimal footnotes carry just die right amount of information for a general audience, and Rose provides plot summaries, particularly helpful for drama now largely forgotten. Thechronologicaltables ofFfrangcon-Davies's stage roles as wellasperformances Reviews429 in film, television, and radio are particularly useful, testifying to the range of her acting ability. She starred in work by Shaw, Wilde, Ibsen, Strindberg, Chekhov, Coward, Rattigan, O'Neill, and above all Shakespeare. She repeatedly played opposite John Gielgud, in Richard ofBordeaux (1922),Romeo andJuliet (1924), The Importance of Being Ernest (1939), and Macbeth (1942). She also played opposite Dirk Bogarde (Summertime, 1955), Anthony Quayle (Long Day's Journey into Night, 1958), and Paul Scofield (Uncle Vanya, 1970). Her career began, however,with what became a signature role in the twenties,when she sang the part ofEtain in the opera The ImmortalHourbyRudand Boughton, first at the Glastonbury Festival in 1919-1920, and in five later productions at Birmingham and London. During World War II she assumed a significant role in the history ofSouth African theater. Together with her friend and long-time companion, Marda Vanne, she laid the groundwork for a South African national theater, culminating in her direction ofMacbeth in Afrikaans in 1950. In an age of e-mail and text messaging, it is heartwarming to read bits of such charming letters. PeggyAshcroft addresses her as"darlingest Gwen, sister, and room mate"; Gielgud closes with "Fondest love from your once skinny Romeo." After seeing her at Stratford, Robert Donat writes that her Beatrice was "absolutely enchanting and completely real." Congratulatory letters also merited gracious replies. On receiving one from Gwen, Glenda Jackson replied, "To know someone you admire likes your work is the greatest of all tributes." Gwen's perspicacity shines through her prose. Gielgud as Benedict looked like Danny Kaye in a ginger wig; Mrs. Smuts...