cssi/SciSciGPT-SciSciNet huggingface dataset:
Wide-FOV FPAs for a shipboard distributed aperture system

The Navy faces an ever evolving threat scenario, ranging from sub-sonic sea skimming cruise missiles to newer, unconventional threats such as that experienced by the USS Cole. Next generation naval technology development programs are developing “stealthy” ships by reducing a ships radar cross section and controlling electromagnetic emissions. To meet these threat challenges in an evolving platform environment, ONR has initiated the “Wide Aspect MWIR Array” program. In support of this program, Raytheon Vision Systems (RVS) is developing a 2560 X 512 element focal plane array, utilizing Molecular Beam Epitaxially grown HgCdTe on silicon detector technology. RVS will package this array in a sealed Dewar with a long-life cryogenic cooler, electronics, on-gimbal power conditioning and a thermal reference source. The resulting sub system will be a component in a multi camera distributed aperture situation awareness sensor, which will provide continuous surveillance of the horizon. We will report on the utilization of MWIR Molecular Beam Epitaxial HgCdTe on Silicon material for fabrication of the detector arrays. Detector arrays fabricated on HgCdTe/Si have no thermal expansion mismatch relative to the readout integrated circuits. Therefore large-area focal plane arrays (FPAs) can be developed without concern for thermal cycle reliability. In addition these devices do not require thinning or reticulation like InSb FPAs to yield the high levels of Modulation Transfer Function (MTF) required by a missile warning sensor. HgCdTe/Si wafers can be scaled up to much larger sizes than the HgCdTe/CdZnTe wafers. Four-inch-diameter HgCdTe/Si wafers are currently being produced and are significantly larger than the standard 1.7 inch x 2.6 inch HgCdTe/CdTe wafers. The use of Si substrates also enables the use of automated semiconductor fabrication equipment.
The two-dimensional vertical jet under gravity

Potential flows under gravity with free surfaces have been somewhat neglected in classical hydrodynamics. We shall concern ourselves with the potential flow through an aperture in the lower plane of a channel bounded by two horizontal planes. We suppose the fluid flows from sources of eiual strength at opposite ends of the infinite channel through the aperture then downward into a sink at infinity. This free surface flow with the channel height infinite, neglecting gravity, was proposed and solved by Kirchhoff [l] 1868. A previous communication [2] deals with a channel of finite height when gravity is neglected. Professor Milne-Thomson considered the effects of gravity on this type of flow, assuming the height of the channel to be infinite. Using his method of tangent flows [3, pp. 307-3101, an expression for the free streamlines was obtained. However, the exact form of the boundaries is unknown. To prevent the apparent paradox of infinite hydrostatic pressure on the lower plane when gravity is acting and the channel height is infinite, the distance between the horizontal planes is assumed to be finite. The purpose of this paper is to discuss this latter flow. Consider the two-dimensional irrotational steady flow of an incompressible inviscid fluid under gravity between two horizontal planes. When an aperture is made in the lower plane, the fluid will issue as a jet bounded by free streamlines along which pressure is constant. The velocity of a particle after passing through the aperture is assumed to increase as the distance of the particle from the aperture increases. We suppose gravity to act vertically downward. The situation is shown in the z-plane diagram in Fig. 1. The distance between the walls is h, the width of the aperture is b, and the origin is taken at B. We suppose the flow in the channel to result from two uniform opposite streams V at A, and A; . The flow is symmetrical about the vertical line DC,. It is shown in [4] that the free streamlines are asymptotic to this vertical line, and therefore meet at infinity. In other respects the form of the free streamlines is unknown. However, we map these unknown curves on the
Pseudotumor Cerebri in Lyme Disease: A Case Report and Literature Review

Pseudotumor cerebri is an unusual presentation of Lyme disease. The case of an 8-year-old girl with pseudotumor cerebri secondary to acute neuroborreliosis is reported. She presented with acute onset of headache, papilledema, sixth nerve palsy, increased intracranial pressure, and cerebrospinal fluid pleocytosis. Serum and cerebrospinal fluid Lyme antibodies were positive. Twelve reported cases that mostly presented with systemic findings and signs of Lyme disease before development of pseudotumor cerebri were reviewed. We conclude that acute neuroborreliosis can present with pseudotumor cerebri as an initial manifestation. It is important to include Lyme disease in the differential diagnosis of pseudotumor cerebri in an area endemic for Lyme disease.
Activation of nuclear factor-κB in the rabbit spinal cord following ischemia and reperfusion

Abstract The transcription factor NF-κB is a ubiquitously expressed inducible regulator of a broad range of genes. Recent studies have shown that activation of NF-κB predominantly is associated with protecting cells from apoptosis, but in some cell models, it is associated with promoting cell death. We used a rabbit spinal cord model of reversible ischemia to determine whether NF-κB was activated by ischemic and reperfusion injury. DNA binding activity of NF-κB was analyzed by an electrophoretic mobility shift assay in animals subjected to varying durations of ischemia and reperfusion. A low level of constitutive NF-κB DNA binding was detected in normal lumbar spinal cord extracts. Animals subjected to a short ischemic insult of 15 min, from which they usually recover neurologic function, had a significant increase in the amount of active NF-κB in nuclear extracts after 18 h reperfusion. There was no change in nuclear NF-κB DNA binding in animals occluded for 60 min that are permanently paraplegic and exhibit extensive neuropathological damage. The amount of deoxycholate-releasable NF-κB sequestered in the cytosol, however, decreased after 18 h reperfusion in rabbits occluded for 60 min. This correlated with a decrease in the amount of RelA(p65) NF-κB subunit. The results suggest that activation of NF-κB after a limited ischemic injury may participate in a neuroprotective response and not in cell death.
TREM-1 and pentraxin-3 plasma levels and their association with obstructive sleep apnea, obesity, and endothelial function in children.

BACKGROUND Obstructive sleep apnea (OSA) is a common health problem in children and increases the risk of cardiovascular disease (CVD). Triggering receptor expressed on myeloid cells-1 (TREM-1) plays an important role in innate immunity and amplifies inflammatory responses. Pentraxin-3 is predominantly released from macrophages and vascular endothelial cells, plays an important role in atherogenesis, and has emerged as a biomarker of CVD risk. Thus, we hypothesized that plasma TREM-1 and pentraxin-3 levels would be elevated in children with OSA. METHODS ONE HUNDRED SIX CHILDREN (MEAN AGE: 8.3 ± 1.6 y) were included after they underwent overnight polysomnographic evaluation and a fasting blood sample was drawn the morning after the sleep study. Endothelial function was assessed with a modified hyperemic test after cuff-induced occlusion of the brachial artery. Plasma TREM-1 and pentraxin-3 levels were assayed using commercial enzyme-linked immunosorbent assay kits. Circulating microparticles (MPs) were assessed using flow cytometry after staining with cell-specific antibodies. RESULTS Children with OSA had significantly higher TREM-1 and pentraxin-3 levels (versus controls: P < 0.01, P < 0.05, respectively). Plasma TREM-1 was significantly correlated with both body mass index (BMI)-z score and the obstructive apnea-hypopnea index (AHI) in univariate models. Pentraxin-3 levels were inversely correlated with BMI-z score (r = -0.245, P < 0.01), and positively associated with endothelial MPs and platelet MPs (r = 0.230, P < 0.01 and r = 0.302, P < 0.01). Both plasma TREM-1 and pentraxin-3 levels were independently associated with AHI in multivariate models after controlling for age, sex, race, and BMI-z score (P < 0.001 for TREM-1 and P < 0.001 for pentraxin-3). However, no significant associations emerged between TREM-1, pentraxin-3, and endothelial function. CONCLUSIONS Plasma TREM-1 and pentraxin-3 levels are elevated in pediatric OSA, and may play a role in modulating the degree of systemic inflammation. The short-term and long-term significance of elevated TREM-1 and pentraxin-3 in OSA-induced end-organ morbidity remains to be defined.
Predictions of the solar wind speed by the probability distribution function model

The near-Earth space environment is strongly driven by the solar wind and interplanetary magnetic field. This study presents a model for predicting the solar wind speed up to 5 days in advance. Probability distribution functions (PDFs) were created that relate the current solar wind speed and slope to the future solar wind speed, as well as the solar wind speed to the solar wind speed one solar rotation in the future. It was found that a major limitation of this type of technique is that the solar wind periodicity is close to 27 days but can be from about 22 to 32 days. Further, the optimum lag between two solar rotations can change from day to day, making a prediction of the future solar wind speed based solely on the solar wind speed approximately 27 days ago quite difficult. It was found that using a linear combination of the solar wind speed one solar rotation ago and a prediction of the solar wind speed based on the current speed and slope is optimal. The linear weights change as a function of the prediction horizon, with shorter prediction times putting more weight on the prediction based on the current solar wind speed and the longer prediction times based on an even spread between the two. For all prediction horizons from 8 h up to 120 h, the PDF Model is shown to be better than using the current solar wind speed (i.e., persistence), and better than the Wang-Sheeley-Arge Model for prediction horizons of 24 h.
Developmental Differences in Rule Learning: A Microgenetic Analysis

Abstract Trial-by-trial strategy assessments and a microgenetic design were used to examine 4- and 5-year-olds' learning of rules for solving balance scale problems. The design allowed us to examine simultaneously the contribution to rule learning of distal variables (qualities and knowledge with which children enter the learning situation) and proximal variables (processes that they execute during learning). Developmental differences in learning arose through two distal variables that were correlated with age—initial rule use and initial encoding-helping older children to execute several proximal processes—noticing the potential explanatory role of a key variable, formulating a more advanced rule, and generalizing and maintaining the rule. Joint consideration of distal and proximal influences seems likely to be generally useful for understanding learning and development.
When autophagy meets viruses: a double-edged sword with functions in defense and offense

Autophagy is a ubiquitous catabolic process that ensures organism’s well-being by sequestering a wide array of undesired intracellular constituents into double-membrane vesicles termed autophagosomes for lysosomal degradation. Interest in autophagy research has recently gained momentum as it is increasingly being recognized to play fundamental roles in diverse aspects of human pathophysiology including virus infection and its subsequent complications. This review discusses recent advances in autophagy studies with respect to virus infection and pathogenesis. A growing body of evidence suggests that the autophagy pathway and/or autophagy genes play pleiotropic functions in the host’s intrinsic, innate, and adaptive immune response against viruses. However, some viruses have evolved to encode virulence factors that evade or counteract the execution of autophagy. Furthermore, certain viruses are equipped to enhance autophagy or exploit the autophagy machinery for their replication and pathogenesis. A comprehensive understanding of the roles of autophagy pathway and autophagy genes during viral infection may enable the discovery of novel antiviral drug targets.
HIGH-LYSINE CORN FRACTIONS AND THEIR CHARACTERISTICS

The protein of high-lysine (opaque-2) corn contains higher levels of lysine and tryptophan and is considered nutritionally superior to that of ordinary yellow dent corn. Both types were dry-milled to grits, meal, flour and degermer fines. High-lysine corn fractions were lower in fat and protein than ordinary dent corn fractions. These fractions were investigated for colour, storage stability, amylograph viscosity, extrusion-cooking, fermentability and baking performance. Colour values of dent fractions were more yellow and darker than those of high-lysine corn fractions. All fractions displayed adequate stability for 56 days at 49°C and for 182 days at either 25° or 37°C as determined by changes in available lysine, fat acidity and flavour of cooked gruels. High-lysine grits had lower pasting temp. than dent grits. Hot paste and setback viscosities were higher for high-lysine fractions. Fermentations were more active for high-lysine than for dent corn fractions, which were extrusion processed. Extrusion-processed high-lysine fractions exhibited less expansion and had higher water solubility values than dent. Baking characteristics were similar when comparisons were made with flour and fines from high-lysine and dent in pancakes and high-lysine and dent meals in corn bread.
Preliminary observations of chondral abrasion in a canine model

Articular cartilage repair was followed for one year in skeletally mature dogs after destabilisation by anterior cruciate ligament transection of the stifle joint (CT), abrasion of the inferior medial condyle (ABR) to bleeding bone, or anterior cruciate transection followed by chondral abrasion (CT/ABR). ABR animals formed repair cartilage at the abrasion site (ABR and CT/ABR) at six months as determined by arthroscopy and at necropsy. CT and CT/ABR animals had an additional cartilage ulcer on the superior aspect of the medial condyle. The abraded site extended in CT/ABR condyles. Repair cartilage (ABR and CT/ABR) contained reduced amounts of proteoglycan as seen by histological loss of safranin O staining and reduced uronic acid content. Fibrocartilage was suggested by histological appearance, hypocellularity, and a higher hydroxyproline content. In contrast with ABR animals, the repair cartilage in the CT/ABR animals contained near normal amounts of hydroxyproline. Collagen profiles of abrasion site repair cartilage in ABR animals had more types I and V collagens, similar amounts of type VI collagen, and decreased amounts of types II, IX, and XI collagens than CT/ABR animals. The results of this study are consistent with abrasion chondroplasty leading to a repair cartilage. Despite extended ulcers, repair cartilage from the destabilised joint (CT/ABR) animals was more hyaline-like in its hydroxyproline content and collagen composition than repair cartilage from the stable joint (ABR animals). In these models additional measures appear to be needed as the defects induced by abrasion chondroplasty did not form a functional hyaline cartilage.
Interface Structure and Stability in Ti/c Superlattices

We have performed a coordinated experimental and theoretical investigation of the structure and stability of Ti/C multilayers. The samples were prepared by conventional techniques and the lattice structure was characterized by X-ray diffraction. Electron Energy Loss and Auger spectroscopies (EELS,AS), in conjunction with Rutherford Backscattering (RBS) were employed to characterize the chemical composition of the samples. It was observed that the Ti/C interface is isolated by a thin titanium oxide layer. The center of the Ti layer gives a typical EELS spectrum of Ti metal. The carbon shows a graphitic character. We have used total energy calculations to study the crystallographic structure and electronic behavior at the interface in Ti-C superlattices. This involved examining a series of structures in the Ti-C system proceeding from the ground state NaCl structure to superlattices. In particular we performed total energy calculations for an arrangement of atoms designed to allow direct investigation of the competition between Ti-C bonds and C-C bonds. We conclude that the equilibrium structure is dominated by C-C bonding and so we find that the interface has a graphite like atomic arrangement rather than a carbide like arrangement. We than further explored the interactions in this graphitic arrangement and found that the interface does not have a significant Ti-C bonding and that the interface most likely consists of simply a layer of graphite adjoining a titanium surface. This carries important implications for the diffusion and bonding at the interface.
A parallel computing approach to viewshed analysis of large terrain data using graphics processing units

Viewshed analysis, often supported by geographic information system, is widely used in many application domains. However, as terrain data continue to become increasingly large and available at high resolutions, data-intensive viewshed analysis poses significant computational challenges. General-purpose computation on graphics processing units GPUs provides a promising means to address such challenges. This article describes a parallel computing approach to data-intensive viewshed analysis of large terrain data using GPUs. Our approach exploits the high-bandwidth memory of GPUs and the parallelism of massive spatial data to enable memory-intensive and computation-intensive tasks while central processing units are used to achieve efficient input/output I/O management. Furthermore, a two-level spatial domain decomposition strategy has been developed to mitigate a performance bottleneck caused by data transfer in the memory hierarchy of GPU-based architecture. Computational experiments were designed to evaluate computational performance of the approach. The experiments demonstrate significant performance improvement over a well-known sequential computing method, and an enhanced ability of analyzing sizable datasets that the sequential computing method cannot handle.
Time and length scales of buoyancy-driven flow structures in a rotating hydromagnetic fluid

Abstract Length and time-scales of buoyancy-driven flow in a rotating hydromagnetic system are investigated to understand better the flow driven by small-scale localized buoyancy in the Earth's core where the Coriolis and Lorentz forces are dynamically important. Both forces introduce anisotropy in the system creating preferred directions which cause the flow to take spatially long (wake) or short (boundary layer) structures. In this paper results of a systematic study of possible quasi-steady flow structures, mainly large-scale ones (i.e., wake modes), in a rotating hydromagnetic flow and of the time scales to establish these modes in an infinite fluid are presented. The wake modes are classified as either primary or non-primary. In the primary modes the fluid velocity is similar in magnitude and direction to that of the buoyant region, while the non-primary modes serve to carry the return mass flux. Four types of primary modes can occur depending on the relative strengths of Lorentz (L), Coriolis (C) and viscous (V) forces: (1) L ⪡ V ⪡ C: well-known Taylor mode (or column) elongated in the direction of rotation; (2) V ⪡ L ⪡ C: a mode similar to the Taylor column elongated in the direction of rotation but foreshortened compared with the case (1) by the effect of the Lorentz force; (3) V ⪡ C ⪡ L: a mode elongated in the direction of magnetic field but foreshortened compared with the case (4) by the effect of the Coriolis force; (4) C ⪡ V ⪡ L: a mode elongated in the direction of magnetic field. Two types of non-primary modes occur. One of the mode is elongated and flattened in the plane of rotation and magnetic field while the other mode is elongated more in the direction of rotation than in the plane perpendicular. Only one primary and one non-primary mode occurs in a given physical situation. Within the Earth's core, two primary wake modes under the influence of the Coriolis and Lorentz forces (case (2) and (3) above) are possible, depending on the size of the magnetic field, which is poorly constrained. When driven by a buoyant region of scale 1 km, these modes have length-scales of order 5–15 km and respond to changes in buoyancy distribution on a timescale short compared with the local advection time. In contrast, the non-primary mode driven by a buoyancy of scale 1 km has a length scale much larger than the radius of the core and a response time long compared with the time of rise through the outer core of the Earth.
Fredholm alternatives for nonlinear A-proper mappings with applications to nonlinear elliptic boundary value problems

Let X and Y be real Banach spaces with a projectionally complete scheme Γ = {Xn, Pn; Yn, Qn} and let T: X → Y be an asymptotically linear mapping which is A-proper with respect to Γ and whose asymptotic derivative T∞ ϵ L(X, Y) is also A-proper with respect to Γ. Necessary and sufficient conditions are given in order that the equation T(x) = ƒ be solvable for a given ƒ in Y. Under certain additional conditions it is shown that solutions can be constructed as strong limits of finite dimensional Galerkin type approximates xn ϵ Xn. Theorems 1 and 2 include as special cases the recent results of Kachurovskii, Hess, Necas, and the author. The abstract results for A-proper mappings are then applied to the (constructive) solvability of boundary value problems for quasilinear elliptic equations of order 2m with asymptotically linear terms of order 2m − 1.
Hormonal control in a state of decreased activation: Potentiation of arginine vasopressin secretion

Behaviorally induced stress is associated with increased arginine vasopressin (AVP) secretion. In this report we describe a phasic conditioned response of AVP secretion yielding 2.6-7.1 times normal plasma concentration of this hormone in association with a physiological state of decreased activation, that associated with the mental technique of "transcendental meditation" (TM) in long-term practitioners (6-8 years of regular elicitation). Such a very large phasic response of AVP was previously unknown in the normal physiology of AVP. This elevation was not accompanied by elevation of plasma osmolality. Unstylized ordinary eyes closed rest in a separate group of subjects studied in the same manner was associated with normal plasma AVP concentration. Galvanic skin resistance (GSR) increased during both TM and rest with significantly larger increase associated with TM. Other measures of activation, including muscle metabolism, and the Spielberger Anxiety Inventory indicated marked relaxation in association with TM. In previous research it has been shown that blood pressure does not change acutely during this behavior. These observations indicate that neither stress nor operation of other usual homeostatic control mechanisms are responsible for elevated for AVP in the meditators. It is speculated that the apparently unique mechanism of TM-induced AVP secretion may be more specifically related to the behavioral effects of meditation.
The Development of the ATC Radar Beacon System: Past, Present, and Future

The ATC radar beacon system is a descendant, through an extended evolutionary development, of military identification friend or foe (IFF) systems begun during World War II. It is today's primary source of surveillance data for air traffic control and performs this function with a high degree of effectiveness. A number of programs are underway to correct its current deficiencies. Looking to the future, the further automation of air traffic control together with the projected growth of air traffic lead to requirements for improved surveillance and communication capability. A discreteaddress mode of beacon system operation, with integral ground-air-ground data link, is under development to meet these needs.
Nuclear gene for mitochondrial leucyl-tRNA synthetase of Neurospora crassa: isolation, sequence, chromosomal mapping, and evidence that the leu-5 locus specifies structural information.

Abstract We have isolated and characterized the nuclear gene for the mitochondrial leucyl-tRNA synthetase (LeuRS) of Neurospora crassa and have established that a defect in this structural gene is responsible for the leu-5 phenotype. We have purified mitochondrial LeuRS protein, determined its N-terminal sequence, and used this sequence information to identify and isolate a full-length genomic DNA clone. The 3.7-kilobase-pair region representing the structural gene and flanking regions has been sequenced. The 5' ends of the mRNA were mapped by S1 nuclease protection, and the 3' ends were determined from the sequence of cDNA clones. The gene contains a single short intron, 60 base pairs long. The methionine-initiated open reading frame specifies a 52-amino-acid mitochondrial targeting sequence followed by a 942-amino-acid protein. Restriction fragment length polymorphism analyses mapped the mitochondrial LeuRS structural gene to linkage group V, exactly where the leu-5 mutation had been mapped before. We show that the leu-5 strain has a defect in the structural gene for mitochondrial LeuRS by restoring growth under restrictive conditions for this strain after transformation with a wild-type copy of the mitochondrial LeuRS gene. We have cloned the mutant allele present in the leu-5 strain and identified the defect as being due to a Thr-to-Pro change in mitochondrial LeuRS. Finally, we have used immunoblotting to show that despite the apparent lack of mitochondrial LeuRS activity in leu-5 extracts, the leu-5 strain contains levels of mitochondrial LeuRS protein to similar to those of the wild-type strain.
Growth in Osteogenesis Imperfecta

Osteogenesis imperfecta is a group of bone fragility conditions most commonly due to a mutation in one of the genes for type 1 pro-collagen. Growth deficiency is a common feature of this condition. Children with the more severe forms of OI have the most significant impacts upon growth. The reasons for poor growth in children with OI are not understood. Subtle deviations in the growth hormone axis have been identified in a subset of children with OI but these abnormalities do not correlate with the type of OI or the degree of growth deficiency. Children with OI generally have normal responses to growth hormone provocative tests and results on serial sampling of spontaneous growth hormone secretion. Hypothesized explanations have focused on factors intrinsic to the defective bone matrix that may result in abnormal responses to growth signals. Treatment for poor growth focuses on optimizing health, nutrition, and function. The role of growth hormone therapy is unclear. A subset of children have short-term acceleration in growth rate when treated with growth hormone in clinical studies.
Assistive technology effects on the employment outcomes for people with cognitive disabilities: A systematic review.

Purpose. This systematic review examines the effects of assistive technology (AT) use on employment outcomes for people with cognitive disabilities (CD). AT is a necessary tool for gaining and maintaining skills for people with CD. Research suggests that AT can assist this population in performing tasks with greater ease and independence.Method. A literature search was conducted to examine the evidence supporting AT use in the workforce. Search criteria included: subjects with CD, use of an AT tool or device and participation in a vocational training program or active employment. The search results yielded nine articles focused on AT interventions used in vocational settings for people with CD.Results. AT interventions demonstrated positive outcomes on job performance. Positive outcomes were measured as a higher rate of accuracy and task completion, increased independence and generalization of skills. We found a trend in the literature over the past 25–30 years, moving from low- to high-tech visual and au...
Mechanical and optical properties of an anelastic polymer at intermediate strain rates and large strains

The mechanical and optical properties of a polyester–styrene copolymer have been investigated by means of drop tests at strain rates from 38 to 113 sec−1 for strains less than 50%. Over this range of rates, the optical behavior was found to be linear with strain and independent of strain rate while the elastic–plastic mechanical behavior was only slightly dependent on strain rate. Comparison with the results of similar experiments at lower strain rates achieved by means of an Instron tester reveals that both mechanical and optical properties vary significantly with strain rate. The variation of flow stress with strain rate was found to obey a power law.
Progress in Sports Neuropsychology

Sports Neuropsychology: Assessment and Management of Traumatic Brain Injury . Ruben J. Echemendia (Ed.). 2006. New York: The Guilford Press, 324 pp., $45.00 (HB). Sports Neuropsychology: Assessment and Management of Traumatic Brain Injury , edited by Ruben J. Echemendia, brings together a variety of experts in the area of sports concussion, in an effort to introduce psychologists and neuropsychologists to the rapidly developing area of sports neuropsychology. The book is organized into five parts. Part I, Sports Neuropsychology in Context , outlines the historical context for the development of sports neuropsychology as a professional endeavor. Chapter 1 (Barth, Broshek, and Freeman), introduces the readers to a number of important definitions that are used throughout the book, including concussion, post-concussion syndrome, second-impact syndrome, and the system of grading concussion severity. Importantly, Barth, a pioneer in the study of sports-related concussion, describes his early efforts at the University of Virginia using pre- and posttrauma assessment with the Sports as a Laboratory Assessment Model (SLAM)—a method of examining concussion in a controlled environment, which has become a standard for current practice. Chapter 2 (Zillmer, Schneider, Tinker, and Kamineris) provides a fascinating historical account of sports-related injuries, dating from the 8th century B.C. (ancient Olympic games) to the present. Their account chronicles the medical and behavioral assessment of head trauma (beginning with Hippocrates, who wrote extensively about head injury), to the modern-day three-tiered grading system introduced by Cantu ( 1986 ) and the American Academy of Neurology ( 1997 ), and provides a unique perspective on how neuropsychologists have come to play such a critical role in sports medicine. Chapter 3 (Echemendia) takes on the important task of highlighting the potential pitfalls inherent in consulting with athletes, including those at the collegiate and professional levels. Echemendia directly confronts the different “rules” associated with athletic consultation (e.g., flexibility of scheduling, dealing with the media) and challenges psychologists to examine their motivation for pursuing this type of specialty practice (i.e., the need to be around “celebrities”). The chapter even describes the down side of sports neuropsychology practice, including not being treated with the same level of professional respect that they are accustomed to receiving from their clients.
Adhesion-related Kinase Repression of Gonadotropin-releasing Hormone Gene Expression Requires Rac Activation of the Extracellular Signal-regulated Kinase Pathway*

Recent studies suggest that adhesion-related kinase (Ark) plays a role in gonadotropin-releasing hormone (GnRH) neuronal physiology. Ark promotes migration of GnRH neurons via Rac GTPase and concomitantly suppresses GnRH gene expression via homeodomain and myocyte enhancer factor-2 (MEF2) transcription factors. Here, we investigated the signaling cascade required for Ark inhibition of the GnRH promoter in GT1-7 GnRH neuronal cells. Ark repression was blocked by the MEK/ERK pathway inhibitor, PD98059, and dominant negative MEK1 but was unaffected by dominant negative Ras. Inhibitors of the Rho family GTPases, Clostridium difficile toxin B (Rho/Rac/Cdc42 inhibitor) and Clostridium sordellii lethal toxin (Rac/Cdc42 inhibitor), blocked Ark inhibition of GnRH transcription. Moreover, dominant negative Rac blunted both Ark activation of ERK and repression of the GnRH promoter, demonstrating an essential role for Rac in coupling Ark to ERK activation. Like Ark, a constitutively active mutant of Rac suppressed GnRH transcription in an ERK-dependent manner. Finally, Ark-mediated repression was significantly attenuated by a dominant negative MEF2C, whereas repression induced by constitutively active Rac was unaffected, indicating that MEF2 proteins are not targets of the Ark → Rac → MEK → ERK cascade. The data suggest that Ark suppresses GnRH gene expression via the coordinated activation of a Rac → ERK signaling pathway and a distinct MEF2- dependent mechanism.
Hot electron studies of lattice damage created in silicon by implantation of 2.8 MeV protons

Abstract In this paper we report the results of a study of the annealing properties of the ionized defect density associated with the damage created in the silicon lattice by implantation of 2.8 MeV protons at room temperature. In particular, the annealing of damage created by implanting to a level of 4.43 × 1012 protons/cm2 is reported. The resulting isochronal annealing curve covered the temperature range from 70°C to 460°C. Two major annealing stages are discussed, one a broad stage between 70°C to 200°C and the other an abrupt annealing stage between 440°C to 460°C. Between the temperature range 200°C to 440°C the number of ionized defects remained relatively constant. Above 460°C no detectable effects of the proton implantation remained.
Categorization and Naming in Children: Problems in Induction.

Categorization and Naming in Children: Problems in Induction. Ellen M. Markman. Cambridge, Mass.: MIT Press, 1989. 250 pp. $27.50 (cloth)
Surface micro-scale semi-heterogeneous structures in compatible polystyrene and poly(vinyl methyl ether) blend thin films investigated by lateral-force microscopy

We have investigated the compatibility of thin films of polystyrene/poly(vinyl methyl ether) (PS/PVME) blends. The macro-compatibility of the blends has been confirmed by differential scanning calorimetry (DSC) and optical microscopy (OM). The topographic image shows a homogeneous morphology with a roughness of only a few nanometers. At the same position, the lateral- force microscopic (LFM) image shows a clear, heterogeneous surface structure. The dispersed phases have domain sizes varying from 100 to 300 nm. Force-distance (F-D) measurements show that both the dispersed phase and the matrix have similar behaviors. The thickness-dependent surface morphology has also been studied; such micro-heterogeneity already exists when the thickness is much higher than that of the ultra-thin films.
An improved generalization of mesh-connected computers with multiple buses

Mesh-connected computers (MCCs) are a class of important parallel architectures due to their simple and regular interconnections. However, their performances are restricted by their large diameters. Various augmenting mechanisms have been proposed to enhance the communication efficiency of MCCs. One major approach is to add nonconfigurable buses for improved broadcasting. A typical example is the mesh-connected computer with multiple buses (MMB). We propose a new class of generalized MMBs, the improved generalized MMBs (IMMBs). We compare IMMBs with MMBs and a class of previously proposed generalized MMBs (GMMBs). We show the power of IMMBs by considering semigroup and prefix computations. Specifically, as our main result we show that for any constant 0</spl epsiv/<1, one can construct an N/sup 1/2 //spl times/N/sup 1/2 / square IMMB using which semigroup and prefix computations on N operands can be carried out in O(N/sup /spl epsiv//) time, while maintaining O(1) broadcasting time. Compared with the previous best complexities O(N/sup 1/8 /) and O(N/sup 1/16 /) achieved on a rectangular MMB and GMMB, respectively, for the same computations, our results show that IMMBs are more powerful than MMBs and GMMBs.
Staphylococcus aureus Is a Major Pathogen in Acute Bacterial Rhinosinusitis: A Meta-Analysis

Background. Acute bacterial rhinosinusitis is a common health problem in the United States. Appropriate recommendations for the treatment of acute bacterial rhinosinusitis are based on the prevalence and expected antimicrobial susceptibilities of specific pathogens. Methods. A meta-analysis was performed on the English language literature from the period 1990‐2006, including prospective studies of antibiotic therapy for acute bacterial rhinosinusitis for which sinus cultures were required in the form of either maxillary sinus taps or middle meatal cultures. Weighted mean culture rates for Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, and Staphylococcus aureus were abstracted from the included articles and compared according to culture technique. Results. Culture rates (i.e., the percentage of patients with positive culture results) were 32.7% for S. pneumoniae, 31.6% for H. influenzae, 10.1% for S. aureus, and 8.8% for M. catarrhalis. No statistically significant difference was seen between the culture rates for S. aureus and M. catarrhalis. Analysis of the effect of culture technique on the culture rates revealed no statistically significant difference. Conclusions. The prevalence of S. aureus among sinus cultures warrants its reconsideration as a major pathogen in acute bacterial rhinosinusitis. As a result, increasing trends of drug-resistant strains may complicate antibiotic recommendations.
Pollinator-mediated competition between two congeners, Limnanthes douglasii subsp. rosea and L. alba (Limnanthaceae).

PREMISE OF STUDY: Pollinator visits are essential for reproduction in many plants, yet interspecific movements of pollinators can also lead to competitive interactions between coflowering species. Pollination-mediated reductions in fertility could potentially lead to exclusion of competing plant species, and may generate spatial variation in the associations among coflowering species across a landscape. METHODS: I documented the potential for heterospecific pollen transfer to cause competitive interactions between two annual grassland species native to California, Limnanthes douglasii subsp. rosea and L. alba, two reproductively incompatible species that have broadly overlapping geographic ranges in the foothills of the Sierra Nevada. I observed pollinator movement in constructed arrays and controlled crosses in the greenhouse and field to investigate the consequences of heterospecific pollen transfer. KEY RESULTS: Pollinators move readily between species when they are presented together in experimental arrays. In the greenhouse, deposition of heterospecific pollen decreased fertility in both species. The decrease in seeds produced per flower was much more pronounced in L. d. rosea (90.6% reduction) than in L. alba (40.8% reduction). In field experiments, L. d. rosea plants that received pollen from heterospecific neighbors first showed >50% reduction in per-flower fertility. CONCLUSIONS: Under natural pollination conditions, heterospecific pollen transfer has the ability to decrease the fertility of L. d. rosea when it occurs at low frequency in mixed stands. Accordingly, pollinator-mediated competition may contribute to the locally disjunct distributions of these two species. It may also influence important restoration decisions in vernal pool habitats.
Nephrotoxicity Risk Factors and Intravenous Vancomycin Dosing in the Immediate Postoperative Period Following Antibiotic-Impregnated Cement Spacer Placement

Background: Several case reports have documented acute kidney injury (AKI) attributable to antibiotic-impregnated cement (AIC) spacers. Objectives: To identify AKI risk factors among patients who underwent AIC placement and determine whether vancomycin-AIC placement affects systemic vancomycin dosing. Methods: Phase 1 was a case-control study to identify AKI risk factors among patients who underwent AIC placement. Cases experienced AKI; controls had unchanged renal function. Phase 2 was a retrospective cohort study. Patients who received ≥72 hours of intravenous (IV) vancomycin were divided into 2 groups according to whether they underwent vancomycin-AIC placement. Primary outcome was number of vancomycin dosing changes. Results: Phase 1: Among 26 cases and 74 controls AKI risk factors on univariate and multivariable analysis included exposure to angiotensin-converting-enzyme (ACE) inhibitor exposure within 7 days of AIC placement (42% vs 20%, P = 0.03) and piperacillin-tazobactam within 7 days following ...
Polycythemia vera and other primary polycythemias.

Purpose of reviewDiagnosis and therapy of polycythemia vera are controversial since the molecular basis of polycythemia vera remains unknown. Distinguishing between polycythemia vera and other polycythemic disorders can be very challenging. The purpose of this review is to discuss the recent progres
Academic Competition among Students of Color: An Interview Study

Forty-one relatively high-achieving students of color were interviewed about the competition for grades that they felt in their high schools. Students of color are particularly interesting with regard to competition because they have sometimes been portrayed as rejecting academic achievement. The students reported competing for grades. They generally thought competition was beneficial. Students commented that they focused on grade point average to help them improve their grades and monitored the grades that other students were receiving. They made almost no comments about competition leading to learning or mastering skills. Their responses are interpreted in light of motivation research that suggests that academic competition and social comparison can lead to maladaptive motivational orientations.
Transverse stiffness: a method for estimation of myocardial wall stress.

Determination of regional ventricular wall stress would allow quantification of both regional contractile state and its interplay with global function. Current methods for quantifying regional stress include mathematical modelling and measurements with strain gauges. Both methods are difficult to validate. We hypothesized that transverse stiffness (i.e., the ratio of indentation stress to strain as the ventricular wall is indented in the direction perpendicular to the wall) would be proportional to the stresses in the plane of the wall and could be used to estimate the latter. To test this hypothesis, 6 arterially perfused canine ventricular septa were mounted in an apparatus that could exert biaxial load in the plane of the wall. A servo system maintained the central third of the septa isometric during active contractions while the septa were paced at 30-60 pulses/min. In the center of the isometric region, a probe of 7 mm diameter indented the septa while the transverse indentation stress and strain were measured. For values of peak systolic in-plane stress from 0.56 to 2.6 g/mm2, the transverse stiffness varied from 1.2 to 11.7 g/mm2 and was linearly related to the in-plane wall stress in each septum (p less than 0.001, ANOVA). After cardioplegia, the transverse stiffness also correlated with passively applied wall stress for each dog (p less than 0.001). The slopes of the individual relations between transverse stiffness and wall stress from active contractions were similar to those from passively applied stress (mean +/- SEM; 1.82 +/- 0.36 versus 1.45 +/- 0.31, NS).(ABSTRACT TRUNCATED AT 250 WORDS)
The relational data file and the decision problem for classes of proper formulas

The Relational Data File (RDF) of The Rand Corporation is among the most developed of question-answering systems. The "information language" of this system is an applied predicate calculus. The atomic units of information are binary relational sentences. The system has an inference-making capacity.As part of the actual construction and implementation of the RDF, a theory was developed by J. L. Kuhns to identify those formulas of the predicate calculus which represent the "reasonable" inquiries to put to this system. Accordingly, the classes of definite and proper formulus were defined, and their properties studied. The definite formulas share a semantic property Kuhns judged as necessarily possessed by a reasonable question to be processed by the RDF. The author has previously shown that the decision problem for the class of definite formulas is recursively unsolvable. The proper formulas are definite, and satisfy additional syntactic conditions intended to make them especially suitable for machine processing. The class of proper formulas depends on which logical primitives are employed. Different primitives give rise to different classes of formulas. A formula which can be effectively transformed into a proper equivalent is admissible. Kuhns conjectures that with respect to one particular class of proper formulas, all definite formulas are admissible. In the paper it is shown that the decision problem for several classes of proper formulas is solvable. The following results are established. Theorem 1: The class of proper formulas in prenex form on any complete set of connectives is recursive. Theorem 2: The class of proper formulas on ¬, ∨, ∃ is recursive. Theorem 3: The class of proper formulas on ¬, ⊃, ∃ is recursive. Theorem 4: The class of proper formulas on ¬, ⊃, ∨, ∃, is recursive. Thus, there is a mechanical decision procedure which determines whether an arbitrary formula is a member of the class. It follows that the analogues of Kuhns' conjecture for these classes are false.
Critical transitions in a game theoretic model of tumour metabolism

Tumour proliferation is promoted by an intratumoral metabolic symbiosis in which lactate from stromal cells fuels energy generation in the oxygenated domain of the tumour. Furthermore, empirical data show that tumour cells adopt an intermediate metabolic state between lactate respiration and glycolysis. This study models the metabolic symbiosis in the tumour through the formalism of evolutionary game theory. Our game model of metabolic symbiosis in cancer considers two types of tumour cells, hypoxic and oxygenated, while glucose and lactate are considered as the two main sources of energy within the tumour. The model confirms the presence of multiple intermediate stable states and hybrid energy strategies in the tumour. It predicts that nonlinear interaction between two subpopulations leads to tumour metabolic critical transitions and that tumours can obtain different intermediate states between glycolysis and respiration which can be regulated by the genomic mutation rate. The model can apply in the epithelial–stromal metabolic decoupling therapy.
Parenting a Second Time Around: An Ethnography of African American Grandmothers Parenting Grandchildren Due to Parental Cocaine Abuse

This study describes a group of six African American grandmothers parenting their grandchildren secondary to cocaine abuse on the part of the parents. It explores the manner in which such parenting affected the grandmothers’ health. Data for this ethnography design were collected through participant observation, field notes, taped interviews, and supplementary data sources. The identification of cultural themes evolved from domain and taxonomic analyses. The themes—parenting a second time around, sacrifice, and God’s presence in daily life—expressed aspects of the grandmothers’ culture. The effects on health varied from none to exacerbation of chronic illnesses. The study results, and its picture of life from the grandmothers’ perspectives, suggest areas of nursing assessment and intervention that otherwise might be left unexplored.