cssi/SciSciGPT-SciSciNet huggingface dataset:
High-temperature performance and radiation resistance of high-efficiency Ge and Si/sub 0.07/Ge/sub 0.93/ solar cells on lightweight Ge substrates

Ge and Si/sub 0.07/Ge/sub 0.93/ alloys are potential candidates for low-bandgap junctions in multijunction solar cells. The radiation resistance of these materials to 1 MeV electrons has been measured, yielding end-of-life/beginning-of-life ratios of about 0.85 at a fluence of 10/sup 16/ electrons/cm/sup 2/. For Ge, the temperature coefficient of efficiency has been determined to be -0.106%/ degrees C under a full AM0 spectrum and -0.048%/ degrees C under a GaAs filter. Si/sub 0.7/Ge/sub 0.93/ cells have shown no performance degradation after exposure to temperatures as high as 500 degrees C, and the temperature coefficient of efficiency for Si/sub 0.07/Ge/sub 0.93/ junctions is about -0.045%/ degrees C, about the same as Si in spite of a lower bandgap by almost 200 meV. >
87Sr optical lattice clocks at JILA

We describe recent experimental progress with the JILA Sr optical frequency standard, which has a systematic uncertainty at the 10−16 fractional frequency level, currently limited by frequency shifts due to atomic interactions and room temperature blackbody radiation (BBR). We will discuss systematic measurements of collisional shifts and provide a complete theory to understand these interaction effects at the 10−17 level. We will also discuss plans to interrogate atoms inside a cryogenic shield region to eliminate BBR shifts. We will present our recent successful efforts in improving the laser stability with the aim for the JILA Sr standard to reach the standard quantum measurement limit and achieve record levels of stability. Finally, a second Sr optical lattice clock has been constructed at JILA, and we will discuss the results of intercomparison experiments between the two standards.
Problems in strain measurement in impact tests on textile materials

The limitations of conventional methods of measuring strain are discussed in light of the structural composition of textile materials. The difficulties introduced in static and impact testing by stress concentration and strain inhomogeneity are considered. The need for two-point strain measurement in regions of homogeneous strain is emphasized. A low inertia strain-measuring system utilizing magnetic tape is described as applied to tensile tests at jaw speeds of 1 to 100 ft./sec.
Lattice incompatibility and a gradient theory of crystal plasticity

Abstract In the finite-deformation, continuum theory of crystal plasticity, the lattice is assumed to distort only elastically, while generally the elastic deformation itself is not compatible with a single-valued displacement field. Lattice incompatibility is shown to be characterized by a certain skew-symmetry property of the gradient of the elastic deformation field, and this measure can play a natural role in a nonlocal, gradient-type theory of crystal plasticity. A simple constitutive proposal is discussed where incompatibility only enters the instantaneous hardening relations, and thus the incremental moduli, which preserves the classical structure of the incremental boundary value problem.
MR monitoring of focused ultrasonic surgery of renal cortex: Experimental and simulation studies

The aim of the study was to test the hypothesis that magnetic resonance (MR) imaging-guided and -monitored noninvasive ultrasonic surgery can be performed in highly perfused tissues from outside the body. A simulation study was performed to evaluate the optimal sonication parameters. An MR-compatible positioning device was then used to manipulate a focused ultrasound transducer in an MR imager, which was used to sonicate kidneys of five rabbits at various power levels and different durations. Temperature elevation during sonication was monitored with a T1-weighted spoiled gradient-echo sequence. The simulation study demonstrated that a sharply focused transducer and relatively short sonication times (30 seconds or less) are necessary to prevent damage to the overlying skin and muscle tissue, which have a much lower blood perfusion rate than kidney. The experiments showed that the imaging sequence was sensitive enough to show temperature elevation during sonication, thereby indicating the location of the beam focus. Histologic evaluations showed that kidney necrosis could be consistently induced without damage to overlying skin and muscle. The study demonstrated that highly perfused tissues such as the renal cortex can be coagulated from outside the body with focused ultrasound and that MR imaging can be used to guide and monitor this surgery.
Epigallocatechin‐3‐gallate selectively inhibits interleukin‐1 β‐induced activation of mitogen activated protein kinase subgroup c‐Jun N‐terminal kinase in human osteoarthritis chondrocytes

Activation of mitogen activated protein kinases (MAPK) is a critical event in pro-inflammatory cytokine-induced signaling cascade in synoviocytes and chondrocytes that lead to the production of several mediators of cartilage damage in an arthritic joint. Green tea (Camellia sinensis) is a widely consumed beverage and we earlier showed that polyphenols present in green tea (GTP) inhibit the development of inflammation and cartilage damage in an animal model of arthritis. In this study we evaluated the role of epigallocatechin-3-gallate (EGCG), a green tea polyphenol which mimics its anti-inflammatory effects, in modulating the IL-1beta-induced activation of MAPK's in human chondrocytes. We discovered that EGCG inhibited the IL-1beta-induced phosphorylation of c-Jun N-terminal kinase (JNK) isoforms, accumulation of phospho-c-Jun and DNA binding activity of AP-1 in osteoarthritis (OA) chondrocytes. Also IL-1beta, but not EGCG, induced the expression of JNK p46 without modulating the expression of JNK p54 in OA chondrocytes. In immunecomplex kinase assays, EGCG completely blocked the substrate phosphorylating activity of JNK but not of p38-MAPK. EGCG had no inhibitory effect on the activation of extracellular signal-regulated kinase p44/p42 (ERKp44/p42) or p38-MAPK in OA chondrocytes. EGCG or IL-1beta did not alter the total non-phosphorylated levels of either p38-MAPK or ERKp44/p42 in OA chondrocytes. These are novel findings and indicate that EGCG may be of potential benefit in inhibiting IL-1beta-induced catabolic effects in OA chondrocytes that are dependent on JNK activity.
Differential transfer benefits of increased practice for constant, blocked, and serial practice schedules

The effects of practice schedule and amount of practice on the development of the generalized motor program (GMP) and on parameter estimation were investigated. Participants (N = 108) practiced the same relative timing but different absolute durations of a multisegment timing task. Practice schedules (constant, blocked, or serial) were crossed with amounts of practice (low and high). Inclusion of a constant practice condition allowed the authors to investigate the variability of practice prediction. Participants practiced the same proportional durations in a serial or a blocked schedule, which enabled the authors to examine contextual interference. A constant practice schedule enhanced GMP performance when task parameters remained the same, but varied practice schedules were beneficial when task parameters changed. A serial as opposed to a blocked practice schedule was superior when the performance of a task governed by a different GMP was required. Increased practice led to a consolidated task representation that was unavailable for updating.
Optimization of spectral intervals for remote sensing of atmospheric temperature profiles

Abstract An expression to evaluate the information content of solutions of the radiative transfer equation other than the minimum-rms solution is derived. This expression can be applied to the problem of selecting the spectral location and number of tropospheric channels for a remote temperature sounder. Application is made to a minimum information solution. The results indicate that three tropospheric channels will suffice, and that it is possible to find a single set of channels which will be nearly optimal over all regions of the globe.
Solid State Bonding of Silicon Chips to Silver Buffer on Copper Substrates

A solid state bonding technique was designed and developed to bond silicon (Si) chips to silver (Ag) buffer layer electroplated on copper (Cu) substrates at a temperature (260°C ) far below the melting temperature of Ag (961°C ). This is possible because Ag atoms in Ag buffer are brought in contact with the gold (Au) atoms in Au layer coated on Si chip. The close proximity in atomic scale allows the Ag and Au atoms to see each other, to share electrons and to bond to each other. The possibility of mating between Au and Ag surfaces relies on the deformation of Ag. Ag, with proper annealing, is ductile and has low yield strength. Its surface can thus deform to conform to and to follow the surface of Au layer coated on Si chip. Its ductile property can also help accommodate large mismatch in coefficient of thermal expansion between Si (2.7×10-6 °C-1) and Cu (17×10-6 °C-1). Ag also has the highest electrical and thermal conductivities among all metals. It is the dream bonding medium. The challenge is to bond Ag to other materials at a temperature compatible to electronic packaging processes, 260°C. In this research, Si chips are coated with thin chromium (Cr) and Au layers and then bonded to Ag buffer plated on Cu substrates. To make Ag buffer ductile, Ag buffer together with Cu substrate is annealed to increase its grain size by a factor of 25. The bonding was performed at 260°C with 1000 psi (6.89 MPa) static pressure. There is no molten phase involved in the bonding process. Scanning electron microscope evaluations show that on the revealed cross section no voids or gaps are observed on Si/Ag and Ag/Cu bonding interfaces. The bonded structure consists of only Si/Cr/Au/Ag/Cu and can sustain at high operating temperature due to high melting temperature of Ag.
Regeneration of pancreatic beta-cell mass for the treatment of diabetes

Introduction: The study of the endocrine compartment of the pancreas (the islets of Langerhans) is of great translational interest, as strategies aimed at restoring its mass could become therapies for glycemic dysregulation in type 1 and 2 diabetes mellitus, drug-related diabetes following diabetogenic therapies or hyperglycemic disturbances following the treatment of cancer and nesidioblastosis. Such strategies generally fall under one of the ‘three Rs,’ namely, replacement (islet transplantation and stem cell differentiation), reprogramming (chiefly from the exocrine compartment of the pancreas) and regeneration (replication and induction of endogenous stem cells). Areas covered: This expert opinion focuses on the latter, as islets are known to regenerate under specific circumstances of physiological (e.g., pregnancy), pathological (e.g., obesity, hyperglycemia, mutations in the glucose-sensing pathway) or experimental (e.g., partial pancreatectomy, cellophane wrapping, partial duct ligation) nature. Th...
Earth's Future Aims to Break Barriers to Interdisciplinary Science

AGU's transdisciplinary journal, Earth's Future, explores topics that intersect science, policy, society, and sustainability. The journal was launched in late 2013. With the goal of better understanding the Earth as an evolving system and human interaction with our planet, this open-access journal strives to be not only a new forum for scientists but also a place where policy makers, industry leaders, and the public can go for information to help them make decisions that affect us all.
Collaborative interaction and responsive environments - sensors that enable individuals and instrument multitudes

Summary form only given. As processors have escalated in capability via Moore's law, electronic sensors have similarly advanced. Rather than dedicate a small number of sensors to hardwired designs that expressly measure parameters of interest, we can begin to envision a near future with sensors as commodity - where dense, multimodal sensing is the rule rather than the exception, and where features relevant to many applications are dynamically extracted from a rich data stream. This article discusses on recent results from several projects at the MIT Media Lab's responsive environments group that explore various embodiments of such dense sensing structures, including high-bandwidth, wireless multimodal sensor clusters, massively distributed, ultra-low-power "featherweight" sensor nodes, and ultra-dense sensor networks as digital "skins". This article focuses on applications that foster collaborative interaction of different sorts, including large interactive surfaces, passive wireless sensors for collaborative musical interaction with multiple players, low-cost sensors for large-group interaction, and electronic badges that facilitate large meetings and acquire data for analyzing social dynamics
On the Theory of Stochastic Processors

Traditional architecture design approaches hide hardware uncertainties from the software stack through over-design, which is often expensive in terms of power consumption. The recently proposed quantitative alternative of stochastic computing requires circuits and processors to be correct only probabilistically and use less power. In this paper, we present the first step towards a theory of stochastic computing. Specifically, a formal model of a device which computes a deterministic function with stochastic delays is presented; the semantics of a stochastic circuit is obtained by composing such devices; finally, a quantitative notion of stochastic correctness, called correctness factor (CF), is introduced. For random data sources, a closed form expression is derived for CF of devices, which shows that there are two probabilities that contribute positively, namely, the probability of being timely with current inputs and the probability of being lucky with past inputs. We show the characteristic graphs obtained from the analytical expressions for the variation of correctness factor with clock period, for several simple circuits and sources.
Oxidative stress hypothesis in Alzheimer’s disease: a reappraisal

Alzheimer's disease (AD) is the most common form of neurodegenerative disorder with dementia. In its sporadic form, AD results from the combination of genetic factors with different epigenetic events. Among them, oxidative metabolic reactions and their by-products have been consistently implicated in AD pathogenesis and represent the biological basis for the 'oxidative stress hypothesis' of AD. Numerous studies demonstrate that different biomarkers of oxidative-stress-mediated events are elevated in the AD brain. Studies in animal models of the disease with antioxidants report significant improvements of their AD-like phenotype. Although epidemiologic studies show that dietary intake of antioxidants reduces the risk of AD, clinical trials with antioxidants show only a marginal positive or no effect. These conflicting results have created a wave of criticism towards the oxidative stress hypothesis of AD. Here, I review the available data and discuss the necessary paths for a fair reappraisal of the hypothesis.
Changes in some biochemical parameters including cytochrome P-450 after hypophysectomy and their restoration by acth administration in rats four months post hypophysectomy

Abstract Following withdrawal of ACTH by hypophysectomy, rat adrenal gland P450 content falls to a low level with a half life time of 3.5 days. The content can be restored by subsequent ACTH treatment in animals as long as four months post hypophysectomy with parallel regeneration of in vitro steroid synthetic capacity. The recovery pattern of a number of other gland parameters suggests that the regeneration of P450 and steroidogenic capacity in these severely atrophied glands occurs by a mechanism which is largely dependent on cell replication.
FUN3D and CFL3D Computations for the First High Lift Prediction Workshop

Workshop, held in Chicago in June 2010. The unstructured-grid code FUN3D and the structured-grid code CFL3D were applied to several different grid systems. The effects of code, grid system, turbulence model, viscous term treatment, and brackets were studied. The SST model on this configuration predicted lower lift than the Spalart-Allmaras model at high angles of attack; the Spalart-Allmaras model agreed better with experiment. Neglecting viscous cross-derivative terms caused poorer prediction in the wing tip vortex region. Output-based grid adaptation was applied to the unstructured-grid solutions. The adapted grids better resolved wake structures and reduced flap flow separation, which was also observed in uniform grid refinement studies. Limitations of the adaptation method as well as areas for future improvement were identified.
Accuracy of the diagnoses of spondylarthritides in veterans affairs medical center databases.

Objective To study the accuracy of diagnoses of spondylarthritides in computerized databases at the Minneapolis Veterans Affairs Medical Center. Methods Medical records were available and reviewed for a random sample of 184 patients from a cohort of 737 patients seen at the rheumatology clinic between January 1, 2001 and July 31, 2002. We compared 4 database definitions with the medical record gold standard of rheumatologists' diagnosis of ankylosing spondylitis (AS), psoriatic arthritis (PsA), or reactive arthritis (ReA): presence of 1) ≥1 or 2) ≥2 International Classification of Diseases, Ninth Revision (ICD-9) diagnostic codes for diagnoses of AS (720.0), PsA (696.0), and ReA (099.3, 711.11–711.19), and presence of 3) ≥1 or 4) ≥2 ICD-9 codes and prescription of a disease-modifying antirheumatic drug (DMARD). Accuracy was assessed by sensitivity, specificity, positive predictive values (PPVs) and negative predictive values (NPVs), kappa statistic, and receiver operator characteristic (ROC) curve area. Results Of 184 patients, 11 (6%) had AS, 17 (9%) had PsA, and 7 (4%) had ReA as per the gold standard. ICD-9 codes for AS, PsA, and ReA were very specific (98–100%) with excellent NPV (99–100%) and PPV (83–100%), good to excellent sensitivity (57–100%), almost perfect kappa agreement (0.72–1), and high ROC curve area (0.79–1). Addition of presence of DMARD prescription to ICD-9 codes of AS and PsA decreased sensitivity to 27–65% without improving the specificity (which was already high at 99–100%). Conclusion The ICD-9 codes for AS, PsA, and ReA in databases are accurate. ICD-9 codes may be used to identify cohorts of patients with spondylarthritides.
Effect of estrogens on the concentration and composition of arterial sterols and steryl esters in male White Carneau pigeons

The effect of short-term (6 months) administration of conjugated equine estrogen (Premarin) on the content and composition of the aortic sterols in male White Carneau pigeons while they were on a cholesterol-free grain diet was investigated. Estrogen treatment resulted in a 38% increase (P < 0.05) in free sterol concentration, with a 28.8% concomitant decrease (P < 0.05) in the percent of cholesteryl esters. The total sterol concentration remained unchanged. This finding suggests that estrogens might influence the synthetic or hydrolytic (or both) processes that control the concentration of cholesteryl esters in the aorta. Fatty acid composition of steryl esters did not change significantly. The cholesterol content of plasma showed a mild reduction (14%) whereas the triglycerides increased significantly (30%).
COLD: Cloud Optimized Workload Deployer

We demonstrate a prototype system called COLD that we are developing at IBM Research which provides optimized deployment of workload in the cloud. A workload refers to an application, consisting of virtual entities (e.g. VM, volume), to be deployed in a cloud infrastructure, consisting of physical entities (e.g. PM, storage). The resource requirements of the virtual entities, as well as metadata describing relations among virtual entities (e.g. location proximity requirement), are described using a declarative workload definition language, namely using a HOT template. COLD provides a clean separation between the underlying mechanisms offered by a given cloud environment for lifecycle management of virtual resources and policies that influence optimal placement. The current implementation of COLD is tied to Open Stack, though we have plans in the future to make it cloud agnostic. It is designed to be fault-tolerant. In a software defined environment of an Open Stack cloud with various hyper visors, we show the operation of COLD to place various Heat stacks that contain specific policies such as rack-level antic location.
Viability assays for frozen semen

The ultimate assay determining viability of frozen semen is the birth of healthy offspring but it requires time and money. Researchers have tried to develop an objective, reliable assay for predicting the fertility of frozen semen immediately after laboratory treatment, avoiding loss of time and expense of multiple breedings in field fertility trials. Bishop (1955) measured 11 characteristics of semen including morphology, metabolism, and motiIity assays and correlated the resuIts with fertility. He reported significant relationships but concluded none were meaningful for determining fertility. Cupps et d. (1953) studied the relationship of sperm concentration, motility, fructolysis index, percentage dead, and percentage abnormal sperm with fertility. They reported correlation values of I = -0.51 for percentage dead and T = -0.83 for percentage abnormal sperm. Stewart et al. (1972) studied seven semen assay techniques including morphoIogy, motility, and motility as measured by the electronic instrument developed by Glover (1968). One significant relationship (I’ < 0.05) between fertility and measured motility was reported, T = 0.41. Hirao (1975) correlated five chemical parameters of semen and motility with fkrtility and reported motility alone (T = 0.654) as significant with simple correla-
The Influence of Fibre Properties on the Properties of Glass-Fibre-Reinforced Polyamide 6,6

We discuss the effect of fibre strength and diameter on the balance of mechanical properties of glass reinforced polyamide 6,6. The results show that the elastic properties of injection moulded short glass fibre reinforced polyamide 6,6 are not strongly influenced by fibre diameter in the 10-17 micron range. The ultimate properties of these composites (strength and Izod impact) showed a clear dependence on fibre diameter and the presence of high strength S-2 glass® fibres. Tensile elongation, tensile and flexural strength, and unnotched Izod impact all decreased significantly over the 10-17 micron diameter range. Notched Izod impact showed a small but significant increase over the same range. Addition of 20% w/w of S-2 glass® to the 17 micron E-glass resulted in an 8% improvement in the fibre contribution to composite strength.
Effects of an oil production effluent on gametogenesis and gamete performance in the purple sea urchin (Strongylocentrotus purpuratus stimpson)

Adult organisms subjected to chronic discharges from a point source of pollution may exhibit several sublethal responses. One such response is the impairment of gamete production. This may be expressed in the amount and/or quality of gametes produced by adults. In this study the effects of chronic exposure to produced water (an oil production effluent) on the gametogenesis and gamete performance of the purple sea urchin (Strongylocentrotus purpuratus Stimpson) were examined using an in situ caging experiment Adult purple sea urchins were kept in benthic cages arrayed down-field from a discharging dif-fuser at 13 sites, with distances ranging from 5 to 1,000 m. Cage exposures were maintained in the field for eight weeks, and each cage held 25 animals Gametogenesis was examined for each sex by comparing a size-independent measure of relative gonad mass as determined by analysis of covariance. Results showed that there was a significant negative relationship between these estimates of relative gonad mass and distance from the outfall for both sexes, indicating that sea urchins living closer to the outfall produced significantly larger gonads. Gamete performance was measured through a fertilization kinetics bioassay that held the concentration of eggs constant and varied the amount of sperm added The proportion of eggs fertilized under each sperm concentration was determined and the response fit to a model of fertilization kinetics This experiment showed significant differences in the fertilizabihty of eggs between cages, and egg fertilizabihty showed a positive relationship with distance away from the outfall These findings indicate that although adult sea urchins exposed to a produced water outfall exhibit larger gonads, they suffer a marked decrease in gamete performance
Postsynaptic actions of neurotensin on preoptic-anterior hypothalamic neurons in vitro.

Abstract This study examines the effects of neurotensin (NT) on single neurons in explants of the preoptic-anterior hypothalamus (POAH) in vitro. Standard in vitro electrophysiological techniques were employed. Cultures were prepared from newborn rats and maintained in roller tubes for 3–4 weeks. NT administered either through the superfusion fluid or via micropressure ejection (0.5–10 psi). Pressure ejection of NT produced a consistent, dose-related, excitatory effect on 71% of the cells studied. The remaining cells were either unresponsive to NT or inhibited by it. In addition, the excitatory effects of microiontophoretically applied glutamate (10–100 nA) were markedly enhanced by NT applied at concentrations that did not alter spontaneous rate. The effects of NT at higher concentrations were additive with glutamate. The effects of NT persisted in Ca 2+ -free medium when synaptic activity was suppressed. These data indicate that NT exerts a potent excitatory effect on single neurons in the POAH in vitro. Moreover, this effect proved to be additive with that of glutamate. The persistence of these effects in Ca 2+ -free medium suggests that the actions of NT are postynapptic in nature.
Homegrown Jihadist Terrorism in the United States: A New and Occasional Phenomenon?

Over the last few years, much attention has been devoted to the phenomenon of homegrown jihadist networks in the West. Most analyses have been based on the dual assumption that this phenomenon has manifested itself only extremely recently and that it is largely limited to Europe. While these two assertions are not completely unfounded, they do not take into consideration significant anecdotal evidence pointing to a long history of homegrown networks inspired by radical Islam operating within the United States. After an extensive overview of such history, the article analyzes the phenomenon of radicalization in America in comparison to Europe and the evolution of U.S. authorities' reaction to it.
Na+, K+‐pump activity and skeletal muscle contractile deficits in the spontaneously hypertensive rat

Skeletal muscles in an animal model of genetic hypertension (the spontaneously hypertensive rat. SHR) exhibit significant deficits in contractile performance. These deficits appear to be unrelated to the rise in blood pressure. Slow-twitch soleus muscles show a decrease in specific muscle tension and a reduced resistance to muscle fatigue during prolonged contractile activity. We tested the hypothesis that the reduced fatigue resistance occurs as a consequence of an impaired ability to maintain or restore Na+ and K+ balance across the sarcolemma during repeated contractions. This may result from a genetically based increase in the Na+ permeability of SHR muscles, coupled with a reduction Na+, K+ pump capacity as the animals mature. Soleus muscles in adult SHR exhibit a significant increase in intracellular Na+ content and a significant decrease in intracellular K+ content at rest. B6RB+ uptake in Na(+)-loaded hypertensive muscles is 45% less than predicted from the number of ouabain-binding sites available. Activation of Na+, K+ pumps using adrenaline or insulin produces a significantly smaller hyperpolarization in hypertensive soleus than in control muscles. Control soleus muscles are hyperpolarized for at least 10 min after a 4 min period of high-frequency activity, but hypertensive soleus muscles remain at resting polarity. Nonetheless, the number of ouabain-binding sites in hypertensive muscle is significantly greater than in control soleus, and binding affinities are similar. This apparent deficit in pump capacity might lead to a greater and more prolonged increase in extracellular K+ during repetitive contractions,and an associated decline in tension. Recently, we have been able to prevent the abnormal decrease in hypertensive soleus fatigue resistance by long-term treatment (8 weeks) with the Ca2+ blocker amlodipine. The therapy prevented or reversed the contractile deficits, but did not restore the responsiveness of the Na+, K+ pump to hormonal stimulation. The current data suggest that both a reduction in Na+, K(+)-pump capacity and changes in Ca2+ distribution play a role in the development of contractile deficits in hypertensive muscles.
Lead isotope systematics of some igneous rocks from the Egyptian shield

Lead isotope data on whole-rock samples and two feldspar separates for a variety of Pan-African (late Precambrian) igneous rocks for the Egyptian Shield are presented. It is pointed out that the eastern desert of Egypt is a Late Precambrian shield characterized by the widespread occurrence of granitic plutons. The lead isotope ratios may be used to delineate boundaries between Late Precambrian oceanic and continental environments in northeastern Africa. The samples belong to three groups. These groups are related to a younger plutonic sequence of granites and adamellites, a plutonic group consisting of older tonalites to granodiorites, and the Dokhan volcanic suite.
The chemical synthesis of the chromogenic substrates H-D-VAL-L-LEU-L-LYS-p-Nitroanilide (S2251) and H-D-ILE-L-PRO-L-ARG-p-NITROANILIDE (S2288)

Abstract We describe detailed procedures for the chemical synthesis of two costly chromogenic substrates, H- D -Val- L -Pro- L -Arg-p-nitroanilide (S2288) and H- D -Val- L -Leu- L -Lys-p-nitroanilide (S2251), which are widely employed for assay of tissue plasminogen activator and plasmin, respectively, as well as in inhibitor assays for these enzymes. Quantities of 5 grams or more of these reagents can be synthesized on a bench-top scale with routine equipment in a laboratory or facility with minimal experience in peptide chemistry. While some of the chemical reactions have been employed previously, improvements have been made therein in this manuscript, and these detailed descriptions are mainly provided to be of service to investigators who employ large quantities of these substrates in their work. The main strategic difference between our methodology and that employed previously is the coupling of the L -Lys- and L -Arg-p-nitroanilides to the previously synthesized, and otherwise completed peptides, which gives superior yields of final product and provides flexibility the chemical synthesis of substrates with other amino acids present.
Reduced hypothalamic-pituitary and sympathoadrenal responses to hypoglycemia in women with fibromyalgia syndrome ☆

Abstract PURPOSE: To perform a detailed comparison of the hypothalamic-pituitary-adrenal axis and the sympathoadrenal system in women with and without fibromyalgia. SUBJECTS AND METHODS: Fifteen premenopausal women who met the 1990 American College of Rheumatology criteria for the diagnosis of fibromyalgia and 13 healthy, premenopausal women were enrolled. We measured baseline 24-hour urinary free cortisol levels and evening and morning adrenocorticotropic hormone (ACTH) and cortisol levels, performed stepped hypoglycemic hyperinsulinemic clamp studies in which serum glucose levels were decreased from 5.0 to 2.2 mmol/L, and compared the effects of infusions of placebo and ACTH. RESULTS: Women with fibromyalgia had normal 24-hour urinary free cortisol levels and normal diurnal patterns of ACTH and cortisol. There was a significant, approximately 30%, reduction in the ACTH and epinephrine responses to hypoglycemia in women with fibromyalgia compared with controls. Prolactin, norepinephrine, cortisol, and dehydroepiandrosterone responses to hypoglycemia were similar in the two study groups. In subjects with fibromyalgia, the epinephrine response to hypoglycemia correlated ( P = 0.01) inversely with overall health status as measured by the fibromyalgia impact questionnaire. Graded ACTH infusion revealed similar increases in cortisol in women with fibromyalgia and healthy controls. CONCLUSIONS: Patients with fibromyalgia have an impaired ability to activate the hypothalamic-pituitary portion of the hypothalamic-pituitary-adrenal axis as well as the sympathoadrenal system, leading to reduced ACTH and epinephrine responses to hypoglycemia.
Gd-DTPA l-Cystine Bisamide Copolymers as Novel Biodegradable Macromolecular Contrast Agents for MR Blood Pool Imaging

The purpose of this study was to synthesize biodegradable Gd-DTPA l-cystine bisamide copolymers (GCAC) as safe and effective, macromolecular contrast agents for magnetic resonance imaging (MRI) and to evaluate their biodegradability and efficacy in MR blood pool imaging in an animal model. Three new biodegradable GCAC with different substituents at the cystine bisamide [R = H (GCAC), CH2CH2CH3 (Gd-DTPA l-cystine bispropyl amide copolymers, GCPC), and CH(CH3)2 (Gd-DTPA cystine bisisopropyl copolymers, GCIC)] were prepared by the condensation copolymerization of diethylenetriamine pentaacetic acid (DTPA) dianhydride with cystine bisamide or bisalkyl amides, followed by complexation with gadolinium triacetate. The degradability of the agents was studied in vitro by incubation in 15 μM cysteine and in vivo with Sprague-Dawley rats. The kinetics of in vivo contrast enhancement was investigated in Sprague-Dawley rats on a Siemens Trio 3 T scanner. The apparent molecular weight of the polydisulfide Gd(III) chelates ranged from 22 to 25 kDa. The longitudinal (T 1) relaxivities of GCAC, GCPC, and GCIC were 4.37, 5.28, and 5.56 mM−1 s−1 at 3 T, respectively. The polymeric ligands and polymeric Gd(III) chelates readily degraded into smaller molecules in incubation with 15 μM cysteine via disulfide–thiol exchange reactions. The in vitro degradation rates of both the polymeric ligands and macromolecular Gd(III) chelates decreased as the steric effect around the disulfide bonds increased. The agents readily degraded in vivo, and the catabolic degradation products were detected in rat urine samples collected after intravenous injection. The agents showed strong contrast enhancement in the blood pool, major organs, and tissues at a dose of 0.1 mmol Gd/kg. The difference of their in vitro degradability did not significantly alter the kinetics of in vivo contrast enhancement of the agents. These novel GCAC are promising contrast agents for cardiovascular and tumor MRI, which are later cleaved into low molecular weight Gd(III) chelates and rapidly cleared from the body.
Evaluation of Acoustic Propagation Paths into the Human Head

Abstract : The overall goal has been to develop an acoustic wave propagation model using well-understood and documented computational techniques that track and quantify an air-borne incident acoustic wave propagated around, into and in the human head. This model serves as a computational tool to elucidate the acoustic wave propagation around, into and in the human head. Specifically, the model determines two features: (1) alternate acoustic propagation paths to the cochlear shell that exist besides the normal air-borne acoustic propagation path (eardrum-ossical path) through the auditory canal and (2) sound pressure amplitude in the cochlear shell (relative to the air-borne sound pressure amplitude) via the alternate propagation paths. A 3D finite-element solid mesh was constructed using a digital image database of an adult male head. Coupled acoustic-mechanical finite-element analysis (FEA) was used to model the wave propagation through the fluid-solid-fluid media. The pressure field in fluid media and the displacement field in solid structures were computed at each time step. Instantaneous acoustic pressure waveforms were recorded at various positions inside and outside of the head model, and propagation trajectories (ray paths) were constructed and evaluated from wavefront normals as a function of frequency and incidence angle. The acoustic loss across the skull was estimated to be approximately 33 dB, consistent with theoretical estimates. The computational ray-path results and the theoretical solutions calculated using Snell's law gave a 0.7 difference for low-angle incidence; 10 difference was obtained for larger angle incidence.
Queer Imag(in)ing: Liminality as Resistance in Lindqvist's Let the Right One In

This essay explores queer imag(in)ing by analyzing a contemporary vampire text, Let The Right One In, by John Ajvide Lindqvist. As I argue, the rhetorical act of humanizing vampires is inherently limiting for (queer) audiences and indicative of processes that seek to clarify, assimilate, and tame—in short, normalize, which as Michel Foucault states “imposes homogeneity” by stamping out difference. Furthermore, I argue that a text can actively resist moments of normalization with the strategic use of what Victor Turner calls liminality—a (queer) rhetorical tactic that resists while seemingly/simultaneously buttressing a liberal humanist belief wherein difference is denied thus displacing and denying the significance of the Other.
Electrically Conducting Materials Based On μ-Tetrathiooxalato-Bridged Bimetallic Ni(II) Anionic Complexes

A series of μ-tto- (tto = C2S42- = tetrathiooxalato) bridged bimetallic Ni(II) complexes with the general formula (Y)2{tto[Ni(L)]2} (where Y = Bu4N+, L = dsit = C3Se2S32- = 2-thioxo-1,3-dithiole-4,5-diselenolato (2) and dmise = C3SeS42- = 2-selenoxo-1,3-dithiole-4,5-dithiolato (3); and where Y = Me4N+ (4) and Et4N+ (5), L = dmit = C3S52- = 2-thioxo-1,3-dithiole-4,5-dithiolato) have been synthesized. The single-crystal X-ray structures of 2, 3, 4 and 5 have been determined: 2, (Bu4N)2{tto[Ni(dsit)]2}, monoclinic, space group P21/c, a = 9.8893(1) A, b = 15.3544(1) A, c = 17.8825(2) A, β = 90.561(1)°, Z = 2; 3, (Bu4N)2{tto[Ni(dmise)]2}, orthorhombic, space group P212121, a = 9.8286(2) A, b = 16.1741(3) A, c = 34.3022(1) A, Z = 4; 4, (Me4N)2{tto[Ni(dmit)]2}, monoclinic, space group C2/m, a = 13.8043(4) A, b = 10.1081(1) A, c = 12.0483(3) A, β = 115.239(1)°, Z = 2; 5, (Et4N)2{tto[Ni(dmit)]2}, monoclinic, space group P21/n, a = 11.8313(1) A, b = 11.0172(2) A, c = 15.3014(1) A, β = 110.951(1)°, Z = 2. All of th...
The pacing stress test reexamined: Correlation of pacing-induced hemodynamic changes with the amount of myocardium at risk

To assess the relation between extent of ischemia and the magnitude of hemodynamic changes, 25 patients (5 with normal coronary arteries and 20 with significant coronary obstructive disease) were studied with rapid atrial pacing and thallium scintigraphy at the time of cardiac catheterization. Hemodynamic variables were measured before, during and after maximal pacing. Thallium was injected intravenously during maximal pacing and scans in three standard views were obtained immediately in the catheterization laboratory, with delayed scans obtained 4 hours after the cessation of pacing. The three thallium scans were each subdivided into five segments, and a thallium score was obtained on the basis of the total number of segments that were hypoperfused. Each patient was assigned a total thallium score corresponding to thallium defects at maximal pacing, as well as a redistributed thallium score corresponding to the difference between thallium score at maximal pacing and that 4 hours later. With pacing, patients with normal coronary arteries demonstrated no significant change in baseline hemodynamic variables, whereas patients with coronary artery disease exhibited a decrease in cardiac index, an increase in systemic vascular resistance, a widening of arteriovenous oxygen difference, an increase in pulmonary capillary wedge pressure and mean pulmonary artery pressure during maximal pacing and an increase in left ventricular end-diastolic pressure immediately after pacing. There was a significant correlation (Spearman rank r = 0.64, p It is concluded that in patients with coronary artery disease the magnitude of pacing-induced hemodynamic changes reflects both the amount of myocardial tissue at ischemic jeopardy and the total mass of hypoperfused myocardium during maximal pacing stress.
Automatic nerve impulse identification and separation

Abstract A heuristic method was developed to identify and to separate automatically unit nerve impulses from a multiunit recording. Up to 20 distinct units can be identified. The method can sequentially decompose superimposed nerve impulses if the rapidly changing region of at least one of them is relatively undistorted. The identification and separation procedure has been successfully applied to the extracellularly recorded neural activity associated with the shadow reflex pathway of the barnacle. The limitations of the procedure are discussed and additional applications of the technique are presented.
Decreased incidence of headache after accidental dural puncture in caesarean delivery patients receiving continuous postoperative intrathecal analgesia

To examine the effects of prolonged (> 24 h) intrathecal catheterization with the use of postoperative analgesia on the incidence of post-dural puncture headache (PDPH), charts of 45 obstetric patients who had accidental dural puncture following attempts at epidural block were reviewed retrospectively. Three groups were identified: Group I (n = 15) patients had a dural puncture on the first attempt at epidural block, but successful epidural block on a repeated attempt; Group II (n = 17) patients had a dural puncture with immediate conversion to continuous spinal anaesthesia with catheterization lasting only for the duration of caesarean delivery; Group III (n = 13) patients had an immediate conversion to spinal anaesthesia and received post-caesarean section continuous intrathecal patient-controlled analgesia consisting of fentanyl 5 micrograms.ml-1 with bupivacaine 0.25 mg.ml-1 and epinephrine 2 micrograms.ml-1 with catheterization lasting > 24 h. No parturient in group III developed a PDPH. This was substantially lower (P 24 h with continuous intrathecal analgesia following accidental dural puncture in parturients may for some patients be a suitable method for providing PDPH prophylaxis and postoperative analgesia.
Intestinal complications in children undergoing chemotherapy for mediastinal non-Hodgkin's lymphoma.

Toxicities involving gastrointestinal tract are common in patients undergoing aggressive chemotherapy for cancer. However, it is uncommon to develop severe ulceration or perforation of the small intestine in absence of direct involvement of the bowel with the malignancy. The authors describe two children who developed severe gastrointestinal complications requiring surgical intervention following initial chemotherapy for non-Hodgkin lymphoma. Both patients had no evidence of small bowel involvement by lymphoma on clinical staging.
On the Determination of an Optimum Microwave Diathermy Frequency for a Direct Contact Applicator

An approximate theoretical analysis is presented for determining the relative heating in a two layer fat-muscle medium due to a dielectric loaded dipole-corner reflector applicator in direct contact with the finite fat layer. The results indicate that convenient applicator sizes, equivalent to those now used at 2450 Mc/s, operating at a frequency in the neighborhood of 750 Mc/s provide the maximum ratio of relative heat per unit volume in the muscle as compared to that in the fat. Experimental data taken with the aid of an electrical model of the fat-muscle layers shows reasonable agreement with the results of the approximate analysis.
New targets for heart-failure therapy: endothelin, inflammatory cytokines, and oxidative stress

Once myocardial damage sufficient to cause clinical heart failure has occurred, there are only limited therapeutic strategies. Most often we seek to achieve maximum function of the remaining viable myocardium through the use of positive inotropic and vasodilating agents. However, as clinicians well know, myocardial dysfunction is progressive. Although the initial insult to the heart (eg, myocardial infarction) may be fairly mild, resulting in little or no immediate reduction in overall cardiac function and no clinically detectable heart failure, over time there is a relentless deterioratioin in both the structure and function of the ventricle, leading to heart failure. Prevention or slowing of progression of the underlying myocardial process may thus be a highly effective pre-emptive treatment for heart failure. The recent appreciation that the rate of disease progression can be slowed has stimulated research into the mechanisms and has focused attention on new approaches to treatment that we are only beginning to understand and use.
Effect on the microstructure of aging Hastelloy B2 from 550 to 850°C for 1,200 hours

Abstract A microstructural examination (using optical and scanning electron microscopy) has been conducted of samples of a Hastelloy B2 alloy, which have been aged from 550 to 850°C for 200, 400, 800, and 1,200 hr. The nickel-based alloy contained 27.7% Mo, 1.0% Cr, 0.8% Fe, 0.3% Mn, and 0.002% C (wt. %). In the solution-annealed condition, the structure is facecentered cubic α. The study used samples of 50 and 800 μm initial α grain sizes. At all aging temperatures, the hardness increased and approximately doubled after aging for about 400 h at 550, 650, and 750°C. At 850°C, it was still increasing after 1,200 h. In the 50 μm initial grain-sized material, aging produced increasing amounts of a Widmanstatten plate structure, with the most prolific amounts at 750°C and the least at 550°C. The formation of this structure was considerably slower in the larger-grained size material since it initiated at the α grain boundaries. The initial formation was by a plate of high Mo content (relative to the matrix) surrounded by a region of low Mo content. This structure developed into a lamellar product, growing lengthwise by the movement of an interface. It appears that the plates are the γ phase (Ni3Mo). Since considerable hardening occurs even when the Widmanstatten structure is not prominent, it is believed that the α has, at least initially, transformed to the β phase (Ni4Mo), as this is known to cause hardening. The structures are discussed in terms of the known Ni-Mo-Fe and Ni-Mo-Cr ternary phase diagrams.
Scattering of elastic waves by three-dimensional surface topographies

Abstract Diffraction of plane harmonic waves by three-dimensional surface irregularities is investigated through the use of an indirect boundary integral equation method. The irregularity of an arbitrary shape is embedded in an elastic half-space and subjected to incident P, SV, SH, and Rayleigh waves. The material of the half-space is assumed to be linear, weakly anelastic, homogeneous and isotropic. The accuracy of the method is demonstrated through comparison of the results with existing axisymmetric solutions. Several numerical examples for non-axisymmetric canyons are presented. The resulting amplification patterns exhibit strong sensitivity on type and angle of the incident waves and on the location of the observation point. Systematic comparisons of three-dimensional and corresponding two-dimensional models demonstrate similarity of the amplification pattern. The amplification is larger in some three-dimensional models than in two-dimensional ones. Strong coupling between SH and P-SV modes is observed for off-azimuthal incident waves. This phenomenon is specially pronounced for incident SH waves and it is intrinsic to three-dimensional scattering.