cssi/SciSciGPT-SciSciNet huggingface dataset:
On-chip 20Gbps high-speed I/O IC test system for signal integrity characterization in flip-chip package

This paper focuses on signal integrity characterization using On-chip 20Gbps high-speed I/O embedded test structures in a flip-chip package. The authors designed On-chip 20Gbps High-Speed I/O Test IC that consists of 20GHz PLL (Phase Locked Loop), 20Gbps PRBS (Pseudo Random Bit Sequence) Generator and 4-port 20Gbps differential CML (Current Mode Logic) I/O. The test IC is designed and simulated in UMC 90nm technology. In addition, the author modeled a test vehicle on to Android Rogers 4350B PCB which is 50Ω matched in HFSS. The vehicle has two patterns; one is a differential microstrip lines pattern which has two different lengths of differential pair traces, the other is differential microstrip lines with multiple vias. Using the test IC and the vehicle, the paper is presented both transient and electromagnetic simulation results for characterizing the signal integrity in flip-chip package.
When You Look Like the Enemy

After the horrific attacks of September 11, 2001, the U.S. Congress’ response to the attacks was the approval of the USA. Patriot Act. This broad legislative policy gave the government investigative powers to fight against terrorism and subsequently targeted those in the Arab, Muslim, and South Asian communities with not just prejudices against these communities, but blatant racism toward innocent people, just because they appear to look like they ‘‘identify’’ with those who have made terrorist threats. The government acted similarly against a group of people in this country that had a supposed connection with a terrorist threat. On Sunday, December 7, 1941, the Japanese attacked Pearl Harbor, Hawaii, and killed over 2,500 Americans. Seventy-three days after the bombing of Pearl Harbor, the government responded by retaliating against those of Japanese ancestry living in the United States. President Franklin D. Roosevelt signed Executive Order 9066 to authorize the military to construct and run 10 internment camps that imprisoned over 120,000 Japanese Americans living on the West Coast in California, Oregon, and Washington. This entire ethnic community living on the West Coast was sent to internment camps in California, Idaho, Utah, Wyoming, Colorado, Arizona, and Arkansas. Two-thirds of those Japanese Americans who were sent to camp were U.S. citizens. The Japanese Americans were removed by themilitary, and thousands were questioned and detained by the Federal Bureau of Investigation (FBI) under the charge of ‘‘military necessity’’ and denied due process, despite the fact that there was no record of sabotage or spying, and their loyalty had been attested to by the FBI and Naval Intelligence. FastforwardtheclocktoSeptember11,2001,asmanypersonsofArab,Muslim,andSouthAsian descent were-and continue to be-rounded up, just like the Japanese Americans were in 1942. If we are to learn anything, we need to learn from Executive Order 9066 and September 11, 2001, and how we as a country treat our citizens in time of paranoia and crisis. We must never forget what happened to the Japanese Americans in 1942 and what continues to happen to the Arab,Muslim, and South Asian Americans, which is hatred toward those that ‘‘look like the enemy.’’ [Brief Treatment and Crisis Intervention 8:209–213 (2008)]
Dynamic crack extension along the interface of materials that differ in their thermal properties: with and without thermal relaxation

Moving surface stresses cause crack extension along the interface of perfectly bonded thermoelastic materials at a constant sub-critical speed. The materials differ only in their thermal properties, and are governed by coupled thermoelastic equations that admit as special cases Fourier heat conduction as well as thermal relaxation with one or two relaxation times. A dynamic steady state of plane strain is assumed. The exact transform solution for a propagating displacement and temperature discontinuity is used to find solutions to the interface crack valid away from the crack edge for low extension speeds and solutions valid at the crack edge for high speeds. Results show that Fourier heat conduction dominates the former case, but solution behavior in the latter is dependent upon the particular thermal model. Thermal mismatch is seen to by itself cause a solution behavior similar to that for bonded dissimilar isothermal elastic solids. In particular, the two-relaxation time solution exhibits both oscillatory and non-oscillatory terms, and the interface temperature at the crack edge is finite.
Induction drive starting by part-winding in autonomous power system

In this article, mathematical model of autonomous power system is suggested including induction drive with part winding starting. With the help of the created model the process of starting is studied, and the results are compared with those of direct starting. The results of the simulations show the effectiveness of the part winding starting that improves all parameters of starting process.
A review of medial temporal lobe and caudate contributions to visual category learning

Here we review recent functional neuroimaging, neuropsychological and behavioral studies examining the role of the medial temporal lobe (MTL) and the caudate in learning visual categories either by verbalizeable rules or without awareness. The MTL and caudate are found to play dissociable roles in different types of category learning with successful rule-based (RB) categorization depending selectively on the MTL and non-verbalizeable information-integration (II) category learning depending on the posterior caudate. These studies utilize a combination of experimental cognitive psychology, mathematical modeling (Decision Bound Theory (DBT)) and cognitive computational modeling (the COVIS model of Ashby et al. [1998. A neuropsychological theory of multiple systems in category learning. Psychological Review 105, 442-481]) to enhance the understanding of data obtained via functional magnetic resonance imaging (fMRI). The combination of approaches is used to both test hypotheses of the cognitive model and also to incorporate hypotheses about the strategies used by participants to direct analysis of fMRI data. Examination of the roles of the MTL and caudate in visual category learning holds the promise of bridging between abstract cognitive models of behavior, systems neuroscience, neuropsychology, and the underlying neurophysiology of these brain regions.
The effects of irradiation with protons on the crystallographic order of the compound Bi2Te2Se

Abstract Specimens of the compound Bi2Te2Se were prepared in the form of pressed powder briquettes and were thermally treated to attain the ordered and the disordered states. These specimens were then subjected to irradiation with 7.5 Mev protons in cumulative doses to a maximum integrated dose of 2 × 1016 protons/cm2. After each irradiation the specimens were examined by x-ray diffraction with monochromated cobalt Ka radiation. In initially ordered specimens, irradiation with protons reduced the lattice order and caused disorder in all three sublattices occupied by bismuth, selenium and tellurium atoms. This disordering is different from thermal disordering, which is contined to the Se and the Te sublattices. Irradiation of specimens with initial thermal disorder produced some lattice order and caused disorder in the Bi sublattice. The final states of order in both the initially ordered and the initially disordered specimens were remarkably similar. The results are interpreted in terms of atomic displace...
Human γδ T Cells and Immune Regulation

Human �� T cells appear to belong to non-classical T cells with both innate and adaptive immune features. V� 2V� 2 (also termed V� 9V� 2) T cell subset exists only in primates, and in humans that represents a major �� T cell subpopulation in the blood. V� 2V� 2 T cells remain to be the only �� T cell subpopulation that can recognize a well- defined foreign microbial phosphoantigen. This article reviews the recent progress in our understanding immune regulation of V� 2V� 2 T cells.
Federal contracts to perform analysis and management services: Can not-for-profits successfully compete?

This study uses a random sample of HUD contracts to determine if not-for-profit organisations have advantages or disadvantages in the competition for fedral procurement awards. Interest focuses on 228 competitors for awards selected in the sample. Differences between for-profit and not-for-profit groups are examined with respect to awareness of opportunity, willingness to compete, abiity to compete technically, and ability to be cost-competitive. Generally, not-for-profit organizations compete well with for-profit ones in efforts to obtain awards to provide analysis and management services. Managers of not-for-profit organizations need not believe that their organizations are incapable of competting successfully against for-profit organizations.
The molecular basis and treatment of primary immunodeficiency disorders

Over the past decade, a number of important advances have been made in the molecular characterization and the treatment of the primary immunodeficiency disorders. These advances include identification of the abnormal genes responsible for such syndromes as X-linked severe combined immune deficiency,
Isolation and Characterization of σ70-Retaining Transcription Elongation Complexes from Escherichia coli

sigma(70) subunit is thought to be released from the core RNA polymerase (RNAP) upon the transition from initiation to elongation or shortly afterward. Here, we identify a population of RNAP from E. coli that retains sigma(70) throughout elongation. The relative amount of this population appears to depend on cellular growth and reaches its maximum during the stationary phase. The proportion of sigma(70)-retaining elongation complexes (EC-sigma(70)) is invariant with various promoters or distances from the transcription start site. EC-sigma(70) responds to pauses, intrinsic terminators, and the elongation factor NusA similarly to EC without sigma(70). However, EC-sigma(70) has a substantially higher ability to support multiple rounds of transcription at certain promoters, suggesting its profound role in gene expression and regulation in bacteria.
Attentional focus on supra-postural tasks affects postural control.

We examined whether the attentional focus adopted on a supra-postural task has an influence on postural control. Similar to Riley, Stoffregen, Grocki, and Turvey (Human Movement Science 18 (1999) 795), participants were instructed to stand still while lightly touching a loosely hanging sheet with their fingertips. However, instructions varied slightly under two conditions: Participants were either asked to minimize movements of the finger (internal focus) or to minimize movements of the sheet (external focus). In contrast to Riley et al.'s findings, both touch conditions resulted in increased postural sway, compared to a baseline condition (no touch). However, in line with previous findings (e.g., Wulf, McNevin, & Shea, Quarterly Journal of Experimental Psychology 54A (2001) 1143), frequency of responding (fast Fourier transformation) was greater under the external focus condition, compared to both internal focus and baseline conditions. The findings indicate improved static balance responses under external focus conditions and compromised static balance response under internal focus conditions.
Intracellular transport of proinsulin in pancreatic beta-cells. Structural maturation probed by disulfide accessibility.

In pancreatic islets, formation of β-secretory granule cores involves early proinsulin homohexamerization and subsequent insulin condensation. We examined proinsulin conformational maturation by monitoring accessibility of protein disulfide bonds. Proinsulin disulfides are intact immediately upon synthesis, but are ≥90% sensitive to in vivo reduction with 2 mM dithiothreitol; wash out of dithiothreitol leads to reoxidation, proinsulin transport, and conversion to insulin. With t ∼10 min, newly synthesized proinsulin becomes resistant to disulfide reduction, correlating with endoplasmic reticulum (ER) export. However, inhibition of ER export with brefeldin A blocks acquisition of resistance to reduction, and once proinsulin arrives in the Golgi, it resists reduction despite brefeldin treatment. Moreover, in vivo, resistance of proinsulin disulfides is overcome after increasing [dithiothreitol] > 10-fold, or in vitro, in islets lysed in a zinc-free, but not a zinc-containing, medium. Employing 30 mM dithiothreitol in vivo, a further decrease in disulfide accessibility is observed following proinsulin conversion to insulin. Incubation of islets with chloroquine or zinc enhances and diminishes accessibility of insulin disulfides, respectively. We hypothesize that two major conformational changes culminating in granule core formation, proinsulin hexamerization and insulin condensation, are sensitive to zinc and occur upon ER exit and arrival in immature secretory granules, respectively.
The New Accountability, Student Failure, and Teachers' Work in Urban High Schools

This study uses Lipsky’s concept of the street-level bureaucrat to identify how English teachers in two Chicago public high schools respond to student failure within the context of a district accountability agenda. Analyses of interview and classroom observation data indicate that teachers’ responses to district policies related to the degree to which teachers perceived the policies as threats to their professional autonomy. Teachers responded to testing policies by allocating significant classroom time to “teaching to the tests” but employed several defensive strategies in response to policies aimed at lowering course failure rates. These strategies may have reduced failure rates but did not remedy student failure.
Screening for Down syndrome in dichorionic twin pregnancies conceived by in vitro fertilization (IVF): a clinical pilot study to confirm the laboratory methods

Purpose The corrections necessary to estimate the risk for Down syndrome in twin pregnancies have been pointed out. We performed a nested controlled study to evaluate the validity of these corrections in dichorionic twins conceived by IVF.
Cholesterol effects megakaryocytopoiesis

Abstract Platelet and lipid profiles are elevated in individuals with atherosclerosis. We examined the effects of cholesterol on megakaryocytopoiesis, since megakaryocytes (MK) give rise to the platelets. Individuals with slightly elevated cholesterol (>190mg/dL; N=22) had lower mean platelet volumes, but higher platelet counts resulting in a higher platelet mass than individuals with lower cholesterol (
Accurate brain volumetry with diffusion-weighted spin-echo single-shot echo-planar-imaging and dual-clustering segmentation: Comparison with volumetry-validated quantitative magnetic resonance imaging

Purpose: Although the diffusion-weighted spin-echo single-shot echo-planar-imaging (DW-SE-sshEPI) is an established quantitative MRI (qMRI) pulse sequence, it is known to be vulnerable to geometric distortions. The purpose of this work is to study is to study brain volumetry accuracy with DW-SE-sshEPI relative previously published volumetry-validated qMRI pulse sequence, specifically the mixed turbo spin-echo (mixed-TSE) pulse sequence, which is robust to magnetic field inhomogeneities and affords much higher spatial resolution. Methods: Twenty-eight subjects were imaged with both DW-SE-sshEPI and mixed-TSE pulse sequences. For each subject, the intracranial structures were segmented using a single-qMRI-channel dual-clustering algorithm (for DW-SE-sshEPI) and a three-qMRI-channel dual-clustering algorithm (for mixed-TSE). The respective intracranial volumes were calculated with both data sets and then compared. Results: The intracranial volumes derived from DW-SE-sshEPI and mixed-TSE data sets are highly and linearly correlated ( R 2 = 0.9353 ) with a slope of 0.9911, with one distorted DW-SE-sshEPI data set demonstrating remarkable volume underestimation. Excluding this outlier resulted in improved linear correlation ( R 2 = 0.9681 ) with a slope of 1.0003. Conclusions: Brain volumetry with DW-SE-sshEPI at 1.5 T data sets can be very accurate for most patients for whom the major magnetic field inhomogeneities result from typical tissue interfaces (e.g., air-tissue or bone-tissue) and typical dental fillings, but not from larger metallic implants.
Molecular biology and pathology of prion strains in sporadic human prion diseases

Prion diseases are believed to propagate by the mechanism involving self-perpetuating conformational conversion of the normal form of the prion protein, PrPC, to the misfolded, pathogenic state, PrPSc. One of the most intriguing aspects of these disorders is the phenomenon of prion strains. It is believed that strain properties are fully encoded in distinct conformations of PrPSc. Strains are of practical relevance to human prion diseases as their diversity may explain the unusual heterogeneity of these disorders. The first insight into the molecular mechanisms underlying heterogeneity of human prion diseases was provided by the observation that two distinct disease phenotypes and their associated PrPSc conformers co-distribute with distinct PrP genotypes as determined by the methionine/valine polymorphism at codon 129 of the PrP gene. Subsequent studies identified six possible combinations of the three genotypes (determined by the polymorphic codon 129) and two common PrPSc conformers (named types 1 and 2) as the major determinants of the phenotype in sporadic human prion diseases. This scenario implies that each 129 genotype–PrPSc type combination would be associated with a distinct disease phenotype and prion strain. However, notable exceptions have been found. For example, two genotype–PrPSc type combinations are linked to the same phenotype, and conversely, the same combination was found to be associated with two distinct phenotypes. Furthermore, in some cases, PrPSc conformers naturally associated with distinct phenotypes appear, upon transmission, to lose their phenotype-determining strain characteristics. Currently it seems safe to assume that typical sporadic prion diseases are associated with at least six distinct prion strains. However, the intrinsic characteristics that distinguish at least four of these strains remain to be identified.
Epigenetics and cardiovascular disease

Despite advances in the prevention and management of cardiovascular disease (CVD), this group of multifactorial disorders remains a leading cause of mortality worldwide. CVD is associated with multiple genetic and modifiable risk factors; however, known environmental and genetic influences can only explain a small part of the variability in CVD risk, which is a major obstacle for its prevention and treatment. A more thorough understanding of the factors that contribute to CVD is, therefore, needed to develop more efficacious and cost-effective therapy. Application of the 'omics' technologies will hopefully make these advances a reality. Epigenomics has emerged as one of the most promising areas that will address some of the gaps in our current knowledge of the interaction between nature and nurture in the development of CVD. Epigenetic mechanisms include DNA methylation, histone modification, and microRNA alterations, which collectively enable the cell to respond quickly to environmental changes. A number of CVD risk factors, such as nutrition, smoking, pollution, stress, and the circadian rhythm, have been associated with modification of epigenetic marks. Further examination of these mechanisms may lead to earlier prevention and novel therapy for CVD.
Mechanisms of Disease: sodium channels and neuroprotection in multiple sclerosis—current status

Axon degeneration is a major contributor to disability in multiple sclerosis, and sodium channels have been shown to have a crucial role in this process. In this article, Waxman reviews the development of the concept of sodium channel blockers as neuroprotectants in multiple sclerosis, and discusses recent attempts to translate this approach from the laboratory to the clinic. Sodium channels can provide a route for a persistent influx of sodium ions into neurons. Over the past decade, it has emerged that sustained sodium influx can, in turn, trigger calcium ion influx, which produces axonal injury in neuroinflammatory disorders such as multiple sclerosis (MS). The development of sodium channel blockers as potential neuroprotectants in MS has proceeded rapidly, and two clinical trials are currently ongoing. The route from the laboratory to the clinic includes some complex turns, however, and a third trial was recently put on hold because of new data that suggested that sodium channel blockers might have multiple, complex actions. This article reviews the development of the concept of sodium channel blockers as neuroprotectants in MS, the path from laboratory to clinic, and the current status of research in this area.
Temperature dependence investigation of the electron paramagnetic resonance of the photorefractive polymer BisA-NAS:DEH

The photorefractive BisA-NitroAminoStilbene polymer (BisA- NAS:DEH) has drawn much attention in recent years due to its potential applications such as terabyte optical data storage, real time optical processing, image amplification, and dynamic holography. Extensive optical investigation for this polymer was performed mostly at room temperature. On the other hand less attention was given to the behavior of this polymer at much higher or lower temperatures than the room temperature. Using the electron paramagnetic resonance technique and a home built temperature controller (minus 190 to 500 degrees Celsius) we have been able to study the temperature effect on the spin concentration of BisA-NAS:DEH in the temperature range from 100 to minus 190 degrees Celsius. An anomalous behavior for the EPR signal was observed near 70 degrees Celsius as the spin density increases drastically especially around 85 degrees Celsius. Also, around minus 25 degrees Celsius the main EPR signal broadened then splits into a doublets which are quenched at higher temperatures. Preliminary interpretation of this signal is given on the basis of behavior of the NAS dye molecule at higher temperature and the transport agent DEH which transfers the charge generated at the dye molecule to the other part of the material, and thus coupling the process of photoconduction.
Microbial community assessment in oil-impacted salt marsh sediment microcosms by traditional and nucleic acid-based indices☆

The effect of oil amendment in salt marsh sediment microcosms was examined by most probable number (MPN), DNA-hybridization with domain-specific oligonucleotide probes and whole community 16S rDNA-hybridizations. Gas chromatography (GC/MS) analysis of oil residues in sediments from microcosms after 3 months of operation showed that the quantity of petroleum hydrocarbons was lower in microcosms amended with oil compared to microcosms amended with oil+plant detritus. Bacterial numbers (total-MPN) increased in all experimental microcosms (amended with plant detritus, oil, and oil+plant detritus). In comparison to the intact sediment, the proportions of oil-degrading bacteria increased >100-fold in the oil amended microcosm and >10-fold in the plant detritus and the oil+plant detritus amended microcosms. DNA-hybridizations with Bacteria, Archaea and Eukarya oligonucleotide probes indicated few changes in the petroleum contaminated sediment community profile. In contrast, rDNA-hybridizations indicated that the bacterial community profile of the oil-impacted sediments, after 1 month of exposure, was significantly different from the control sediment.
Medications and breast-feeding: Current concepts

Abstract Objectives To describe the various factors that come into play when a breast-feeding mother is taking medications, including use of prescription drugs, over-the-counter medications, recreational drugs, galactogogues, and herbal remedies and to provide a framework used for counseling breast-feeding women. Setting Community and hospital pharmacy and health care settings. Practice description Consultative services provided to breast-feeding mothers who had been prescribed or were using medications. Main outcome measures Use of pharmacokinetic factors, maternal and child factors, a list of questions to ask breast-feeding mothers, and a stepwise approach to counsel breast-feeding mothers on the compatibility of using medications while breast-feeding. Results By positive intervention of pharmacists and health care providers, up to 1 million breast-feeding mothers, who must use medications, can continue to breast-feed while taking medications. Conclusion Objectively weighing the benefits of drugs and breast-feeding versus the risks of drugs and not breast-feeding, in most cases, allows for pharmacists to give current and practical advice to mothers and other health professionals who counsel mothers.
A Chloride Channel Model

Miller explains in his Perspective [also see report by Malashkevich et al . (p. 761)] why the new pentameric coiled-coil structure of the extracellular matrix protein COMP is exciting for students of ion channels. The narrow channel created by the coils holds not only water but a chloride ion.
Septohabenular connections in the rat, cat and monkey

Septohabenular projections were studied using the Nauta-gygax method of staining degenerating axons. The results are in general agreement with those reported by others. However, the septum projects differentially to the habenula and the patterns differ slightly in the three species studied. Rostral parts of the septum projected to the lateral habenular nucleus and posterior parts to the medial nucleus. Dorsal and ventral structures of the septum had a slight dorsal ventral topography of projection in the stria medullaris thalami. Projection through the stria medullaris was confined to its medial part only in the rat. The largest number of fibers to bypass the habenula and terminate in the mesencephalic central gray occurred in the monkey.
Effects of Adrenocortical Steroids and of Adrenocorticotrophic Hormone on (Na+-K+)-ATPase in Immature Cerebral Cortex

Summary: The effect of cortisol, niethylprednisolone, and ACTH on (Na+-K+)-ATPase activity in developing cerebral cortex has been measured. Stimulation of (Na+-K+)-ATPase by these agents has been found in whole brain homogenates of kittens as early as age 8 days, and in whole homogenates and light microsomal fractions of young rats at 14 and 28 days. (Na+-K+)-ATPase activity in animals treated with corticosteroids or ACTH for 4 days was found to be 15–30% higher than activity in littermate controls. Brain potassium concentration was increased in 14-day-old rats treated with methylprednisolone. Speculation: Corticosteroid hormones and ACTH are effective in the treatment of seizures in infancy, especially in patients with infantile spasms and hypsarrhythmia. Stimulation of (Na+-K+)-ATPase activity by these hormones provides a plausible mechanism for the anticonvulsant effect.
Theory of fluctuations in a plasma

Abstract A theory of electron density fluctuations in a two-component plasma of electrons and positive ions is developed within the random phase approximation. A dielectric formulation is used extensively to describe the fluctuations; investigation of various examples clarifies such facets as collective vs. individual particle aspects of fluctuations. It is shown that the collective part of the fluctuation spectrum can also be obtained from the kinetic equations derived by Pines and Schrieffer, which describe the time rate of change in the distributions of collective and individual particle modes due to the excitation of collective oscillations by fast electrons and their decay into individual particle modes. It is shown that the collective part of electron density fluctuations exhibits a huge increase as the plasma approaches from a region of stability a critical point corresponding to the onset of plasma wave instabilities; consideration of the theory of electromagnetic wave scattering leads us to predict enormously enhanced scattering of the electromagnetic radiation at certain angles, a phenomenon which is analogous to the critical opalescence for a liquid-gas phase transition. The influence of the scattering of the holes by impurities (for a plasma in a semiconductor) is studied and it is found that impurity scattering acts to shift the position of the onset of the instability, but does not alter appreciably the existence of critical fluctuations in the vicinity of the critical point. It is also shown that the electron density fluctuation spectrum obeys a certain sum rule. In the Appendix it is demonstrated that the method of super-posing the dressed particles (electrons or ions plus their associated screening clouds) is a direct consequence of the random phase approximation.
Cycling Willingness: Investigating Distance as a Dependent Variable in Cycling Behavior Among College Students

Abstract We present a novel approach to understanding distance as a barrier to cycling and its use as a dependent variable in multinomial logistic regression. In doing so, this study explores distances in relation to spatially and relevant human factors such as gender and propensity to cycle among college students. College students (N = 949) participated in a health survey and stated possible predictors of cycling based on their cycle usage and preferences in the previous 30 days. While utilizing GIS in a bicycle-friendly network, we created geo-statistical GIS-groupings and performed multinomial logistic regression analysis. We examined college students to discover how their demographic and personal characteristics may mediate the deterrent properties of distance when considered as a dependent variable in cycling to a college campus. Age and propensity for cycling for transportation mediate the negative effect of distance on the likelihood of cycling. The findings also suggest that infrastructure improvements could lessen the impact of distance as a barrier to cycling and increase the likelihood of cycling for commuting.
Chirality-dependent excited-state quenching of Eu(dpa)33− and Tb(dpa)3+3 luminophores by diastereomeric structures of Δ-[Co(trans-1,2-cyclohexanediamine)3]3+ in aqueous solution

Abstract Four diastereomers of Δ-[Co( trans -1,2-cyclohexanediamine) 3 ] 3+ are examined as enantioselective excited-state quenchers of chiral Eu(dpa) 3 3− and Tb(dpa) 3 3− luminophores (dpadipicolinate dianion) in solution. In their quenching actions, all four diastereomers can distinguish between and interact differentially with the Λ and Δ enantiomers of the luminophores, but their enantiomeric preferences show interesting variations that may be correlated with chelate-ring conformational structure.
Instability of equatorial protons in Jupiter's mid-magnetosphere

Two different models for the distribution function are fit to the Jovian protons seen by Pioneer 10 inbound. The models reproduce the observed energy and angular distributions. These models are then used to assess the collisionless mirror instability. Because of the pancake proton angular distributions in the equatorial ring current region, the ring current particle population appears to be mirror unstable at times, with instability growth rates of about 10 min. Such a time is consistent with observed proton flux autocorrelation times. An instability such as this (there are other candidates) may be responsible for the previously established proton flux flowing parallel to the magnetic field away from the equatorial region.
Expansion of cultured Zinnia mesophyll cells in response to hormones and light.

Mesophyll suspension cultures of Zinnia elegans L. have been used extensively to investigate the development of tracheary elements. Here we have modified the culture conditions to promote cell expansion and inhibit tracheary element differentiation and cell division. Cell expansion, measured by computer image analysis, was stimulated by auxin (α-naphthyleneacetic acid), cytokinin (N 6 -benzylaminopurine), gibberellic acid, brassinosteroid (24-epibrassinolide), and light, all of which are known to promote cell expansion in whole plants or excised organs. Whereas light stimulated cell expansion primarily during the first 48 h of culture, auxin, cytokinin, gibberellic acid and brassinosteroid had little effect until after 48 h. Treatments also differed in their relative effects on cell elongation and radial cell expansion. Light and cytokinin had a greater effect on radial cell expansion, auxin and epibrassinolide promoted only cell elongation, and gibberellic acid had nearly equal effects on expansion in both directions. We have also shown by combining treatments that the effects of cytokinin and auxin are additive. Neither hormone treatment, however, was additive with the effect of light treatment, Finally, in contrast to xylogenic cultures where expansion occurs by tip growth, cell expansion in non-differentiating cells was due to diffuse growth. These data show that cell expansion can be induced by hormones in primary mesophyll cultures from Zinnia in contrast to serially transferred plant suspension cultures. Furthermore, they indicate that auxin, cytokinin, and light induce cell expansion by different mechanisms in these cultures.
Thermal time shifting: leveraging phase change materials to reduce cooling costs in warehouse-scale computers

Datacenters, or warehouse scale computers, are rapidly increasing in size and power consumption. However, this growth comes at the cost of an increasing thermal load that must be removed to prevent overheating and server failure. In this paper, we propose to use phase changing materials (PCM) to shape the thermal load of a datacenter, absorbing and releasing heat when it is advantageous to do so. We present and validate a methodology to study the impact of PCM on a datacenter, and evaluate two important opportunities for cost savings. We find that in a datacenter with full cooling system subscription, PCM can reduce the necessary cooling system size by up to 12% without impacting peak throughput, or increase the number of servers by up to 14.6% without increasing the cooling load. In a thermally constrained setting, PCM can increase peak throughput up to 69% while delaying the onset of thermal limits by over 3 hours.
Acupuncture and relaxation response for substance use disorder recovery

Background & Aims: Substance abuse is a major health problem in the US population, particularly among veterans. Current treatments for substance abuse in the form of pharmacologic, behavioural, or psychosocial therapy can be effective in limited instances. We investigated the effect of using two complementary and alternative approaches, acupuncture and the relaxation response, to treat veterans who are recovering from substance use disorders.Methods: We conducted a controlled trial at a US Veterans Administration homeless residential rehabilitation programme. Study participants were randomly assigned to acupuncture, relaxation response or usual care groups.Results: Both acupuncture and the relaxation response interventions were well received by the veterans with high intervention attendance rates (75% and 80%, respectively). The acupuncture group had significantly greater reductions in craving and anxiety levels and greater improvements in the spirituality dimension of quality of life, while the relaxatio...
Effect of Normal Strains in Buckling of Thick Orthotropic Shells

An improved elasticity solution to the problem of buckling of orthotropic cylindrical shells sub- jected to external pressure is presented. The 2D axisymmetric cylindrical shell is studied (ring approximation). Specifically, in the development of the governing equations and boundary conditions for the buckling state, the solution includes the terms with the prebuckling normal strains and stresses as coefficients (i.e., the terms and , which were neglected in the earlier work as being too small compared to the terms and 00 e s9 s e9 s9 kk ij kk ij ij , respectively). The formulation results in a two-point boundary eigenvalue problem for ordinary differential 0 sv 9 kk j equations in r, with the external pressure p as the parameter. The results show that the effect of including the normal strains and stresses is to further decrease the critical load. This decrease (versus the earlier elasticity solution without these terms) depends on the shell thickness and is generally moderate, and in no event com- parable with the (quite large) decrease of the elasticity versus the shell theory prediction. This decrease depends also on the degree of orthotropy, and it is smaller for the isotropic case. Finally, a formula is derived for the critical pressure based on a first-order shear deformation formulation, and the comparison shows an improvement versus the classical shell for thick shells, but still the elasticity solution is noticeably lower than the first-order shear deformation prediction.
The Association of Complete Laryngotracheoesophageal Cleft With Left Lung Agenesis: Pathophysiological Clues Provided by an Experiment of Nature

The authors present a patient with complete laryngotracheoesophageal cleft and concurrent left lung agenesis and microgastria. Prenatal ultrasound scan showed polyhydramnios and a hypertrophic right lung. The authors propose that the combination of right lung hypertrophy, polyhydramnios, and microgastria in the absence of a competent laryngeal mechanism may suggest that the preferential path for swallowed amniotic fluid was into the lung, rather than the normal route through the stomach. This case illustrates the prenatal findings suggestive of complete laryngotracheoesophageal cleft and lung agenesis, and suggests a potential causal relationship between shunting of swallowed amniotic fluid into the bronchial tree and prenatal lung hypertrophy and microgastria.
Effects of carbon dioxide on the alpha frequency and reaction time in humans.

Summary The effects of acute exposure (5 min) to carbon dioxide (0–7.9%) on the EEGs and reaction times of five humans were investigated. Alpha frequency and alpha amplitude were recorded from the central and from the occipitalparietal areas of the scalp while subjects reacted with their right index finger to flashes of light. Variance analyses indicated that the percentage CO 2 inhaled significantly affected alpha frequency and reaction time. Alpha frequency and reaction time were significantly faster under the 0–5.5% CO 2 conditions than under the 7.9% CO 2 condition. A slight increase in alpha frequency and decrease in reaction time were evident under the 3.5 and 5.5% CO 2 conditions as compared to the 0 and 1.5% CO 2 conditions.
A dissociation between object manipulation spatial ability and spatial orientation ability

We developed psychometric tests of spatial orientation ability, in which people are shown a two dimensional array of objects, imagine taking a perspective within the array, and indicate the direction to a target object from this perspective. Patterns of errors on these tests were consistent with experimental studies of perspective taking. Characteristic errors and verbal protocols supported the validity of the perspective-taking tests, suggesting that people encoded the objects in the display with respect to a body-centered coordinate system when the imagined perspective was more than 90° different from the orientation of the display. By comparing alternative models in a confirmatory factor analysis, we found that the ability to mentally rotate and manipulate an imagined object (as measured by tests of spatial visualization and spatial relations) and the ability to reorient the imagined self (as measured by the perspective-taking tests) are separable spatial abilities.
Speech coding: a tutorial review

The past decade has witnessed substantial progress towards the application of low-rate speech coders to civilian and military communications as well as computer-related voice applications. Central to this progress has been the development of new speech coders capable of producing high-quality speech at low data rates. Most of these coders incorporate mechanisms to: represent the spectral properties of speech, provide for speech waveform matching, and "optimize" the coder's performance for the human ear. A number of these coders have already been adopted in national and international cellular telephony standards. The objective of this paper is to provide a tutorial overview of speech coding methodologies with emphasis on those algorithms that are part of the recent low-rate standards for cellular communications. Although the emphasis is on the new low-rate coders, we attempt to provide a comprehensive survey by covering some of the traditional methodologies as well. We feel that this approach will not only point out key references but will also provide valuable background to the beginner. The paper starts with a historical perspective and continues with a brief discussion on the speech properties and performance measures. We then proceed with descriptions of waveform coders, sinusoidal transform coders, linear predictive vocoders, and analysis-by-synthesis linear predictive coders. Finally, we present concluding remarks followed by a discussion of opportunities for future research. >
Crystal structure of an isoleucine-zipper trimer

Subunit oligomerization in many proteins is mediated by short coiled-coil motifs. These motifs share a characteristic seven-amino-acid repeat containing hydrophobic residues at the first (a) and fourth (d) positions. Despite this common pattern, different sequences form two-, three- and four-stranded helical ropes. We have investigated the basis for oligomer choice by characterizing variants of the GCN4 leucine-zipper dimerization domain that adopt trimeric or tetrameric structures in response to mutations at the a and d positions. We now report the high-resolution X-ray crystal structure of an isoleucine-containing mutant that folds into a parallel three-stranded, alpha-helical coiled coil. In contrast to the dimer and tetramer structures, the interior packing of the trimer can accommodate beta-branched residues in the most preferred rotamer at both hydrophobic positions. Compatibility of the shape of the core amino acids with the distinct packing spaces in the two-, three- and four-stranded conformations appears to determine the oligomerization state of the GCN4 leucine-zipper variants.
Post-traumatic stress disorder: emerging concepts of pharmacotherapy

Post-traumatic stress disorder (PTSD) can result from a traumatic experience that elicits emotions of fear, helpless or horror. Most individuals remain asymptomatic or symptoms quickly resolve, but in a minority intrusive imagery and nightmares, emotional numbing and avoidance, and hyperarousal persist for decades. PTSD is associated with psychiatric and medical co-morbidities, increased risk for suicide, and with poor social and occupational functioning. Psychotherapy and pharmacotherapy are common treatments. Whereas, research supports the efficacy of the cognitive behavioral psychotherapies, there is insufficient evidence to unequivocally support the efficacy of any specific pharmacotherapy. Proven effective pharmacologic agents are sorely needed to treat core and targeted PTSD symptoms, and for prevention. This review describes current and emerging pharmacotherapies that advance these goals.
The Physical State of Nafcillin Sodium in Frozen Aqueous Solutions and Freeze-Dried Powders

ABSTRACTThe purpose of this study was to develop a better understanding of the physical chemistry of freeze drying of lyotropic liquid crystals using nafcillin sodium as a model solute. Solutions and freeze-dried powders of nafcillin sodium were studied by polarized light microscopy, differential scanning calorimetry, x-ray powder diffraction, and water vapor adsorption. Differential scanning calorimetry thermograms of nafcillin sodium solutions contain a melting endotherm at approximately -5.5°C and, depending on the concentration and heating rate, a crystallization exotherm immediately after this endotherm followed by the melting endotherm of ice. When the sample is annealed at -4°C, both the endotherm and exotherm are eliminated, and a new endotherm appears at approximately -1°C on the shoulder of the ice-melting endotherm. The data are interpreted as melting of a liquid crystalline phase, followed by crystallization. X-ray powder diffractograms of unannealed freeze-dried nafcillin sodium are consisten...
Calcium Supplementation Prevents Seasonal Bone Loss and Changes in Biochemical Markers of Bone Turnover in Elderly New England Women: A Randomized Placebo-Controlled Trial

Elderly women are at increased risk for bone loss and fractures. In previous cross-sectional and longitudinal studies of women residing in northern latitudes, bone loss was most pronounced during winter months and in those consuming less than 1 g calcium per day. In this study we sought to test the hypothesis that calcium supplementation by either calcium carbonate or dietary means would prevent seasonal bone loss and preserve bone mass. Sixty older postmenopausal women without osteoporosis were randomized to one of three treatment arms: Dietary milk supplementation (D-4 glasses of milk/day), Calcium carbonate (CaCO3-1000 mg/day in two divided doses), or placebo (P). After 2 yr, placebo-treated women consumed a mean of 683 mg/day of calcium and lost 3.0% of their greater trochanteric (GT) bone mineral density (BMD) (P < 0.03 vs. baseline); Dietary supplemented women averaged a calcium intake of 1028 mg/day and sustained minimal loss from the GT (-1.5%; P = 0.30), whereas CaCO3-treated women (total Ca intake, 1633 mg/day) suffered no bone loss from the GT and showed a significant increase in spinal and femoral neck BMD (P < 0.05). Femoral bone loss occurred exclusively during the two winters of the study (i.e. total loss, -3.2%; P < 0.02 in placebo-treated women) with virtually no change in GT BMD during summer. Serum 25-OH vitamin D declined by more than 20% (P < 0.001) in all groups during the winter months but returned to baseline in summer; PTH levels rose approximately 20% (P < 0.001) during winter but did not return to baseline during the summers. Urine N-telopeptide and osteocalcin levels increased significantly but only in the P-treated women and only during winter. Serum insulin growth factor binding protein 4, an inhibitory insulin growth factor binding protein, rose 15% (P < 0.03) from summer to winter, but this increase was significant only in those women consuming <1000 mg/day of calcium. By multivariate analysis, total calcium intake was the strongest predictor of bone loss from the hip. Urinary N-telopeptide also closely correlated with GT BMD but only during winter (P = 0.003). We conclude that calcium supplementation prevents bone loss in elderly women by suppressing bone turnover during the winter when serum 25-OH vitamin D declines and serum PTH increases. The precise amount of calcium necessary to preserve BMD in elderly women requires further studies, although in this study, at least 1000 mg/day of supplemental calcium was adequate prophylaxis against femoral bone loss.
Top Search Progress in CDF

The discovery of the top quark t has been, for more than 10 years, a missing key confirmation of the Standard Model. Together with the proof of its existence, the knowledge of its mass, production, and decay properties will improve our current understanding and have implications for new physics. Lower limits on the t mass, mt, have been 27 GeV from TRISTAN,1 and 41 GeV from UA1.2 There are theoretical arguments that limit the top mass to be less than 180–200 GeV.3 The observation of the top quark is one of the main physics goals of the Collider Detector at Fermilab (CDF).4