cssi/SciSciGPT-SciSciNet huggingface dataset:
The Role of CT and MRI in the Emergency Evaluation of Persons with Suspected Stroke

As a growing number of therapeutic treatment options for acute stroke are being introduced, multimodal acute neuroimaging is assuming a growing role in the initial evaluation and management of patients. Multimodal neuroimaging, using either a CT or MRI approach, can identify the type, location, and severity of the lesion (ischemia or hemorrhage); the status of the cerebral vasculature; the status of cerebral perfusion; and the existence and extent of the ischemic penumbra. Both acute and long-term treatment decisions for stroke patients can then be optimally guided by this information.
Signal Processing Methods for Removing the Effects of Whole Body Vibration upon Speech

Humans may be exposed to whole-body vibration in environments where clear speech communications are crucial, particularly during the launch phases of space flight and in high-performance aircraft. Prior research has shown that high levels of vibration cause a decrease in speech intelligibility. However, the effects of whole-body vibration upon speech are not well understood, and no attempt has been made to restore speech distorted by whole-body vibration. In this paper, a model for speech under whole-body vibration is proposed and a method to remove its effect is described. The method described reduces the perceptual effects of vibration, yields higher ASR accuracy scores, and may significantly improve intelligibility. Possible applications include incorporation within communication systems to improve radio-communication systems in environments such a spaceflight, aviation, or off-road vehicle operations.
Reactions of ethylidene on a model chromia surface: 1,1-dichloroethane on stoichiometric α-Cr2O3 (101¯2)

The reaction of CH{sub 3}CHCl{sub 2} over the nearly-stoichiometric {alpha}-Cr{sub 2}O{sub 3} (10{sub {bar 1}} > 2) surface produces an ethylidene intermediate that yields primarily gas phase CH{sub 2}{double_bond}CH{sub 2} and surface chlorine adatoms; however, trace amounts of HC{triple_bond}CH, CH{sub 3}CH{sub 3}, H{sub 2} and CH{sub 3}CH{double_bond}CHCH{sub 3} are also observed. A rate-limiting intramolecular isomerization (2,1-hydrogen shift) in the surface ethylidene species produces gas phase CH{sub 2}{double_bond}CH{sub 2}. The chlorine freed from the dissociation of CH{sub 3}CHCl{sub 2} binds at the five-coordinate surface Cr{sup 3+} sites on the stoichiometric surface, completing the octahedral coordination sphere, and inhibits the surface chemistry by simple site blocking. No surface carbon deposition is observed from the thermal reaction of 1,1-dichloroethane under the conditions of this study, demonstrating that the ethylidene intermediate is not a primary coke forming intermediate over (10{sub {bar 1}} > 2) facets of {alpha}-Cr{sub 2}O{sub 3} under the conditions of this study.
Decreased protein binding and thiopental kinetics

Thiopental kinetics and protein binding were determined in seven surgical patients with chronic renal failure and a thiopental free fraction of 28.0 +/- 6.5% (SD) and in seven age- and weight-matched normal surgical patients with a thiopental free fraction of 15.7 +/- 2.4%. Thiopental clearance, based upon total plasma concentrations, rose from 3.2 +/- 0.6 ml/kg/min in the normal group to 4.5 +/- 1.1 ml/kg/min in the chronic renal failure group. Volume of distribution at steady state, also based on total drug concentrations, rose from 1.9 +/- 0.5 l/kg in the normal group to 3.0 +/- 1.0 l/kg in the chronic renal failure group. These changes in clearance and volume of distribution at steady state are secondary to changes in free drug distribution and elimination. When kinetics were calculated from free drug concentrations, the intrinsic clearance, unbound volume of distribution at steady state, and free fraction in tissues in the normal and renal failure groups did not differ substantially. These data suggest that the kinetic changes based on total drug concentrations are secondary to changes in free fraction in plasma. In chronic renal failure patients, the underlying rate and extent of thiopental distribution and elimination are much the same as in normal patients.
Reversibility of cholinephosphotransferase in lung microsomes.

The effect of cytidine 5′-monophosphate (CMP) on the incorporation of cytidine 5′-diphosphate (CDP) [methyl-14C]choline or [1-14C]dipalmitoylglycerol into phosphatidylcholine (PC) catalyzed by rabbit lung microsomal CDP choline:1,2-diacyl-sn-glycerol cholinephosphotransferase (EC 2.7.8.2) was studied. In the presence of 0.85 mM CMP and nonsaturating diacylglycerol concentration, the incorporation of CDP[14C]choline into PC was markedly stimulated, but the incorporation of [14C]dipalmitoylglycerol into PC was inhibited. This was due to the increase of endogenous diacylglycerol generated from microsomal PC by the cholinephosphotransferase reverse reaction. However, the newly synthesized PC was not readily hydrolyzed in the presence of CMP. The results of this study suggest that the endogenous membranous diacylglycerol is utilized more preferentially for PC synthesis than the exogenous diacylglycerol and that the newly synthesized PC could rapidly equilibrate with the endogenous membrane PC pool.
The Postpartum Period in Women with Epilepsy

For women with epilepsy (WWE), the postpartum period is a vulnerable time owing to medication alterations, disrupted sleep, increased stress, and the challenges of breastfeeding. Sleep deprivation and the stress of having a new child can be challenging for WWE. Concerns over antiepileptic drugs (AEDs) in breast milk and sleep disruption associated with breastfeeding leads some WWE to discontinue breastfeeding. Adjustment of AEDs in the postpartum period can lead to difficulties in seizure control. Postpartum depression is increased in WWE, and patient education about newborn safety remains a concern. This article covers these important topics in postpartum WWE.
Low-Angle Tracking by Carrier-Free Radar

Multipath transmission is currently the most important limitation for the accuracy of low-elevation-angle radar. The use of properly polarized nonsinusoidal electromagnetic waves permits one to discriminate between the wave that propagated directly from the radar to the target and back, and all the other waves that propagated via the surface of the earth, either on the way to the target or on the way back (first-order multipath transmission). The effect works both over water, a good conductor, and over dry land, a good insulator. It appears that the error due to first-order multipath transmission can be essentially eliminated. As a fringe benefit, one avoids the enormous propagation losses incurred when pulses with a duration of about 1 ns are transmitted with the help of a sinusoidal carrier. (A similar polarity-reversal effect, that exists for circularly polarized sinusoidal waves, cannot be used for an all-weather radar because of the high absorption losses.)
pH control in nitrate uptake studies with excised roots

In the investigation of NO 3 − uptake by excised roots, pH of salt solutions can be effectively controlled by periodic additions of a cation exchange resin, Amberlite IR-120, in the H+ form. This method of pH control provides for the addition of H+ to systems without an accompanying anion which might influence the absorption of NO 3 − . The resin appeared to provide a favorable buffering capacity during an extended period and the method was especially useful for NO 3 − uptake studies conducted at high root-to-solution ratios.
Unusual aspects of inner cell mass formation, endoderm differentiation, Reichert's membrane development, and amniogenesis in the lesser bulldog bat, Noctilio albiventris

Background and Methods The early embryogenesis of the lesser bulldog bat, Noctilio albiventris (family Noctilionidae), was examined histologically in 59 pregnant females collected from a reproductively synchronized population in Colombia. Results Early blastocysts of Noctilio are unusual in lacking a typical inner cell mass. Instead, cells inside of the trophoblast are dispersed for a period as a monolayer. A typical inner cell mass (ICM) only forms and becomes properly oriented after the initiation of implantation. Several features of Reichert's membrane in this species are also noteworthy: it develops between the ICM and trophoblast and between the parietal endoderm and trophoblast; it becomes linked to a meshwork of basal laminalike material that extends into the ICM; and it appears to be continuous, or fused, with prominent basal laminae that develop within the cytotrophoblastic villi that radiate throughout the preplacenta. Amniogenesis occurs by cavitation and converts the ICM into a hollow epiblastic vesicle. Gastrulation commences before this vesicle exhibits obvious differentiation into an embryonic shield and amniotic ectoderm. Conclusions Because development and proper orientation of a typical ICM in Noctilio occur after the initiation of implantation, these may involve the migration of cells on the interior of the blastocyst and/or an unusual method of early endoderm differentiation. The possibility exists that epiblast, endoderm, and cytotrophoblast may all contribute to the secretion of Reichert's membrane in this bat. Although the early embryogenesis of Noctilio exhibits many similarities to that in phyllostomid bats, substantial differences also exist between these closely related species. © 1996 Wiley-Liss, Inc.
Multiprocessor cache design considerations

In this paper, cache design is explored for large high-performance multiprocessors with hundreds or thousands of processors and memory modules interconnected by a pipe-lined multi-stage network. The majority of the multiprocessor cache studies in the literature exclusively focus on the issue of cache coherence enforcement. However, there are other characteristics unique to such multiprocessors which create an environment for cache performance that is very different from that of many uniprocessors.Multiprocessor conditions are identified and modeled, including, 1) the cost of a cache coherence enforcement scheme, 2) the effect of a high degree of overlap between cache miss services, 3) the cost of a pin limited data path between shared memory and caches, 4) the effect of a high degree of data prefetching, 5) the program behavior of a scientific workload as represented by 23 numerical subroutines, and 6) the parallel execution of programs. This model is used to show that the cache miss ratio is not a suitable performance measure in the multiprocessors of interest and to show that the optimal cache block size in such multiprocessors is much smaller than in many uniprocessors.
Principal component analysis and spatial correlation: Environmental analytical software tools

Abstract Using principal component analysis and geostatistics, the authors have reexamined the results of a study of chlorinated dibenzodioxins and dibenzofurans in Hamburg (Germany) Harbor sediments. These methods identified the same anomalous samples as the original study, but without recourse to the more difficultly obtained isomer-specific chemical analyses. In addition, they revealed in the remaining data a trend highly suggestive of two spatially and chemically discrete sources for nearly all (>90%) of the subject compounds found in the study, once again using no isomer-specific data. All of the above was done with readily available, public-domain software.
Wired on sugar: the role of the CNS in the regulation of glucose homeostasis

Obesity and type 2 diabetes mellitus (T2DM) — disorders of energy homeostasis and glucose homeostasis, respectively — are tightly linked and the incidences of both conditions are increasing in parallel. The CNS integrates information regarding peripheral nutrient and hormonal changes and processes this information to regulate energy homeostasis. Recent findings indicate that some of the neural circuits and mechanisms underlying energy balance are also essential for the regulation of glucose homeostasis. We propose that disruption of these overlapping pathways links the metabolic disturbances associated with obesity and T2DM. A better understanding of these converging mechanisms may lead to therapeutic strategies that target both T2DM and obesity.
Theory of the Firm

I carved a massive cake of beeswax into bits and rolled them in my hands until they softened … Going forward I carried wax along the line, and laid it thick on their ears. They tied me up, then, plumb amidships, back to the mast, lashed to the mast, and took themselves again to rowing. Soon, as we came smartly within hailing distance, the two Sirens, noting our fast ship off their point, made ready, and they sang … The lovely voices in ardor appealing over the water made me crave to listen, and I tried to say ‘Untie me!’ to the crew, jerking my brows; but they bent steady to the oars. (Homer, c. –900, pp. 227–28)
Abstract 2032: MicroRNA control of tumor cell plasticity in a new tumor metastasis model

Proceedings: AACR 101st Annual Meeting 2010‐‐ Apr 17‐21, 2010; Washington, DC We have developed a new prostate cancer model to discover the molecular changes underlying metastasis. A series of cell lines were developed by isolating metastatic cells from lymph nodes of nude mice following orthotopic injection of DU145 human prostate cancer cells and expression changes analyzed using gene chips. We found that these DU145-LN cells exhibit a mesenchymal-epithelial transition (MET). Repeated rounds of in vivo metastatic selection progressively increased the expression of epithelial markers including E-cadherin, cytokeratin-18 and EpCAM, and decreased mesenchymal markers such as vimentin. Despite being more epithelial, DU145-LN cells are more migratory and show reduced proliferation in vitro. However, they show increased tumorigenesis when reinjected into nude mice. Interestingly, clinical metastases are frequently epithelial, despite strong evidence that EMT enhances metastasis. To explain this, current models of metastasis invoke EMT with subsequent MET at the secondary site. Our cells appear to demonstrate this plasticity making them an ideal model system for studying MET regulation. The MET changes in the DU145-LN cells suggested a coordinated mechanism of regulation. MicroRNA arrays revealed several candidates which correlated with the epithelial phenotype. DU145-LN cells showed increased expression of the miR-200 family (a, b, c and miR-141), and treatment with synthetic miR-200 inhibitors resulted in reduced cell-cell interactions and decreased E-cadherin levels. Our data complement recent evidence showing down-regulation of miR-200 by EMT. miR-200 acts in a feedback loop with the transcription factor ZEB1 to regulate EMT. We also observed significantly reduced expression of an additional microRNA not previously linked to cell morphology in the DU145-LN cells. Transfection of precursor miRNA to this target altered the epithelial morphology and reduced E-cadherin levels, suggesting an additional pathway of MET/EMT control. We are currently determining the mechanism of action of this new microRNA target. Our data support a role for MET in tumor metastasis, and indicate that microRNAs are an important mechanism mediating tumor cell plasticity and EMT/MET. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2032.
The Functional Expression of Sodium-dependent Bile Acid Transport in Madin-Darby Canine Kidney Cells Transfected with the cDNA for Microsomal Epoxide Hydrolase

Previous studies have suggested that the enzyme microsomal epoxide hydrolase (mEH) is able to mediate sodium-dependent transport of bile acids such as taurocholate into hepatocytes (von Dippe, P., Amoui, M., Alves, C., and Levy, D.(1993) Am. J. Physiol. 264, G528-G534). In order to characterize directly the putative transport properties of the enzyme, a pCB6 vector containing the cDNA for this protein (pCB6-mEH) was transfected into Madin-Darby canine kidney (MDCK) cells, and stable transformants were isolated that could express mEH at levels comparable with the levels expressed in hepatocytes. Sodium-dependent transport of taurocholate was shown to be dependent on the expression of mEH and to be inhibited by the bile acid transport inhibitor 4,4'-diisothiocyanostilbene-2,2'disulfonic acid (DIDS), as well as by other bile acids. Kinetic analysis of this system indicated a Km of 26.3 microM and a Vmax of 117 pmol/mg protein/min. The Km value is essentially the same as that observed in intact hepatocytes. The transfected MDCK cells also exhibited sodium-dependent transport of cholate at levels 150% of taurocholate in contrast to hepatocytes where cholate transport is only 30% of taurocholate levels, suggesting that total hepatocyte bile acid transport is a function of multiple transport systems with different substrate specificities, where mEH preferentially transports cholate. This hypothesis is further supported by the observation that a monoclonal antibody that partially protects (26%) taurocholate transport from inhibition by DIDS in hepatocytes provides almost complete protection (88%) from DIDS inhibition of hepatocyte cholate transport, suggesting that taurocholate is also taken up by an alternative system not recognized by this antibody. Additional support for this concept is provided by the observation that the taurocholate transport system is almost completely protected (92%) from DIDS inhibition by this antibody in MDCK cells that express mEH as the only bile acid transporter. These results demonstrate that mEH is expressed on the surface of hepatocytes as well as on transfected MDCK cells and is able to mediate sodium-dependent transport of taurocholate and cholate.
EFFECTIVENESS OF A HIGH-PRESSURE WATER-FOGGING SYSTEM IN CONTROLLING DUST EMISSIONS AT GRAIN RECEIVING

Grain dust at the receiving area is a fire hazard, a health concern, and a sanitation problem and should be controlled. The effectiveness of a high-pressure water-fogging system in controlling grain dust emissions was evaluated with corn and wheat while spouting 2.1 m3 (60 bu) of grain into a test chamber. Dust/fog emissions and deposits along with entrained airflows were measured for four fog treatments, a control, and an air-blower treatment at each of two grain flow rates. The uncontrolled dust emissions varied with grain type and grain flow rate. Water-fog sprays, when applied across the top of the test chamber, redirected the airflow downstream of the spray nozzles and reduced dust emissions significantly. Dust reductions ranged from 60% to 84% for corn and from 35% to 73% for wheat. However, the sprays produced significant fog emissions and deposits in proportion to the liquid supply. At the highest spray rate (855 g/min), fog emission was 32 g/min (3.8%), and fog deposits ranged from 1.4 to 7.1 mg/cm2/min.
Multiple antibiotic allergy syndrome

Allergists/immunologists are commonly referred patients with histories of multiple antibiotic allergies and must determine what antibiotics they can safely use. This review covers articles published through September 2003. The history and definition of multiple antibiotic allergy syndrome are discussed. The clinical and laboratory evidence suggesting that certain individuals make allergic antibody to unrelated antibiotics is explored. A framework for dealing with this potentially vexing problem on a clinical level is developed. Areas that require additional research and development are outlined.
Experimental autoimmune myasthenia gravis: effects of calcium and potassium on the spontaneous release of neuromuscular transmitter.

Abstract The mechanism of spontaneous transmitter release at the neuromuscular junctions of rats with experimental autoimmune myasthenia gravis (EAMG) was studied by varying the extracellular calcium and potassium concentrations and measuring the frequency of miniature end-plate potentials (MEPPs). Quantitative comparisons between the changes in MEPP frequency in rats with EAMG and normal rats indicate that there is no significant difference between the two groups of animals. Similar studies of the effects on MEPP frequency of elevated temperature, guanidine hydrochloride, and 2,4-dinitrophenol show that the frequency changes in EAMG are comparable to those in the controls. As in control rats, the random occurrence of MEPPs in EAMG closely follows a Poisson distribution. These results demonstrate no abnormality in spontaneous transmitter release from the motor nerve terminals in EAMG and support the concept that EAMG is primarily a postsynaptic disorder.
Academic leadership: reflections in the key of C

Abstract The opinions expressed herein by the author(s) do not necessarily reflect the official endorsement of The Association of Medical School Pediatric Department Chairs, Inc.
The normal esophageal lead electrocardiogram.

Abstract The esophageal lead electrocardiogram has been analyzed in 40 normal subjects. As a rule, the records at ventricular levels closely resembled those from left chest leads. Near the atrioventricular groove (transition zone) and at atrial levels, an intrinsic deflection in the P wave, a deep broad Q, progressively smaller R and deeper S, and inverted T waves appeared. Immediately behind the atria, the P wave was of shorter duration, of greater complexity in configuration, and of greater voltage in all its components than elsewhere. T a (auricular repolarization) waves were frequently present in leads from this region. At these same levels, the ventricular complexes approached the configuration seen in Lead aV R , and at supra-atrial levels were almost identical. The P wave became inverted in the supra-atrial leads and resembled that seen in aV R . The maximum and minimum duration and amplitude of each component of the esophageal lead electrocardiogram are given in tabular form. A comparative study of brass and nickel-silver esophageal lead electrodes shows that there are at most minute differences in the records obtained with each type. Brass electrodes appear suitable for use as esophageal lead electrodes.
Navigational strategies underlying phototaxis in larval zebrafish

Understanding how the brain transforms sensory input into complex behavior is a fundamental question in systems neuroscience. Using larval zebrafish, we study the temporal component of phototaxis, which is defined as orientation decisions based on comparisons of light intensity at successive moments in time. We developed a novel “Virtual Circle” assay where whole-field illumination is abruptly turned off when the fish swims out of a virtually defined circular border, and turned on again when it returns into the circle. The animal receives no direct spatial cues and experiences only whole-field temporal light changes. Remarkably, the fish spends most of its time within the invisible virtual border. Behavioral analyses of swim bouts in relation to light transitions were used to develop four discrete temporal algorithms that transform the binary visual input (uniform light/uniform darkness) into the observed spatial behavior. In these algorithms, the turning angle is dependent on the behavioral history immediately preceding individual turning events. Computer simulations show that the algorithms recapture most of the swim statistics of real fish. We discovered that turning properties in larval zebrafish are distinctly modulated by temporal step functions in light intensity in combination with the specific motor history preceding these turns. Several aspects of the behavior suggest memory usage of up to 10 swim bouts (~10 sec). Thus, we show that a complex behavior like spatial navigation can emerge from a small number of relatively simple behavioral algorithms.
An unusual polymorphic locus useful for tagging Rps1 resistance alleles in soybean

The Phytophthora root and stem resistance locus Rps1 has been mapped to linkage group N of the USDA-ARS soybean molecular map, approximately 2 cM from locus A071-1. To determine if A071-1 polymorphisms exist that distinguish and tag different Rps1 alleles, germplasms containing the seven Rps1 alleles were screened with eight enzymes for pA071-detectable polymorphisms. Six enzymes revealed at least one polymorphic fragment. All six detected a polymorphism at A071-1 as determined by restriction fragment length polymorphism mapping, comparison to an EMBL3 clone containing locus A071-1, and Southern hybridization with probes specific for locus A071-1. Screening of the Rps1 donors and 24 Rps1-and 15 Rps1-containing U.S. soybean varieties showed that locus A071-1 exhibited three polymorphisms with each enzyme. The polymorphisms detected by one enyme did not always correlate with those detected by the other four, suggesting that multiple mutation events may be responsible for the different A071-1 polymorphisms. Although no combination of alleles distinguished Rps1-and Rps1-containing genotypes, polymorphism at A071-1 made it possible to distinguish five groups of soybean germplasms. Thus, the unusual polymorphism of locus A071-1 should useful for following Rps1 inheritance in many breeding programs.
Black strings and p -branes are unstable

We investigate the evolution of small perturbations around black strings and branes which are low energy solutions of string theory. For simplicity we focus attention on the zero charge case and show that there are unstable modes for a range of time frequency and wavelength in the extra 10[minus][ital D] dimensions. These perturbations can be stabilized if the extra dimensions are compactified to a scale smaller than the minimum wavelength for which instability occurs and thus will not affect large astrophysical black holes in four dimensions. We comment on the implications of this result for the cosmic censorship hypothesis.
DNA Polymerases as Therapeutic Targets

Numerous pathological states including cancer, autoimmune diseases, and viral/bacterial infections are often attributed to uncontrollable DNA replication. Inhibiting this essential biological process provides an obvious therapeutic target against these diseases. A logical target is the DNA polymerase, the enzyme responsible for catalyzing the addition of mononucleotides into a growing polymer using a DNA or RNA template as a guide for directing each incorporation event. This review provides a summary of therapeutic agents that target polymerase activity. A discussion of the biological function and mechanism of polymerases is first provided to illustrate the strategy for therapeutic intervention as well as the rational design of various nucleoside analogs that inhibit various polymerases associated with viral infections and cancer. The development of nucleoside and non-nucleoside inhibitors as anti-viral agents is discussed with particular emphasis on their mechanism of action, structure-activity relationships, toxicity, and mechanism of resistance. In addition, commonly used anti-cancer agents are described to illustrate the similarities and differences associated with various nucleoside analogs as therapeutic agents. Finally, new therapeutic approaches are discussed that include the inhibition of selective polymerases involved in DNA repair and/or translesion DNA synthesis as anti-cancer agents.
Effects of photoperiod and castration on post-fast food intake and body weight gain in golden hamsters ☆

This experiment examined the effects of photoperiod and castration of post-food-restriction food intake and body weight gain in male golden hamsters (Mesocricetus auratus). Hamsters were ether castrated or sham-operated and housed in a 14:10 light-dark (LD) or a 8:16 LD cycle for 8 weeks. All animals were restricted to a 6 g of chow per day for 13 days and then returned to ad lib feeding. Following food restriction the hamsters gained weight rapidly without overeating. The long photoperiod (LD 14:10) increased post-restriction weight gain in castrated hamsters but decreased weight gain in gonadally intact animals. These differences in body weight gain were associated with significant group differences in feed efficiency (grams weight gain per gram eaten). The results suggest that changes in energy utilization may be more important than changes in energy intake in the adaptation of hamsters to food restriction.
Accuracy of self-reported cigarette smoking among pregnant women in the 1990s

In large, prospective studies of pregnancy conducted in the 1960s, women reported very accurately whether or not they smoked. However, in the 1990s, pregnant women who smoke are often pressured to reduce or quit smoking, and the incentive to misreport may be greater than in the past. To assess the accuracy of reported smoking, the authors compared self-reported smoking with cotinine in the serum and/or urine of 105 women who participated in the Calcium for Pre-eclampsia Prevention pilot study in 1992. Cotinine confirmed the report of 84.6% of women who reported smoking and 94.5% of women who denied smoking. These fractions are virtually identical to those obtained in a pregnancy cohort from the 1960s. The authors conclude that in the setting of two obstetrical research studies not specifically focused on smoking, the accuracy of self-reported cigarette smoking did not change substantially from the 1960s to the 1990s.
The solution structure of HIV-1 Nef reveals an unexpected fold and permits delineation of the binding surface for the SH3 domain of Hck tyrosine protein kinase.

The solution structure of HIV-1 Nef has been solved by multidimensional heteronuclear NMR spectroscopy. The construct employed to circumvent problems associated with aggregation was a double-deletion mutant (Δ2–39, Δ159–173) in which conformationally disordered regions of the protein at the N terminus and in a long solvent-exposed flexible loop were removed, without affecting the properties or structural integrity of the remainder of the protein. Despite the absence of any sequence similarity, the overall fold of Nef is reminiscent of that of the family of winged helix-turn-helix DNA binding proteins. The binding surface of Nef for the SH3 domain of Hck tyrosine protein kinase has been mapped and reveals a non-contiguous (in terms of amino-acid sequence) interaction surface. This unique feature may suggest possible avenues for drug design aimed at inhibiting the interaction between Nef and SH3 domains.
Secure Communication by low-photon-number pathlength modulation

Pathlength modulation interferometers operating at the single-photon level allow the transmission of conventionally encrypted messages with greatly increased security. By modulating pathlength differences, Alice and Bob can prevent Eve from having access to the ciphertext.
Reducing Morbidity of Thoracoabdominal Aneurysm Repair by Preliminary Axillofemoral Bypass

Abstract Background : Thoracoabdominal aneurysm (TAA) repair continues to be associated with appreciable morbidity and mortality. To reduce the substantial cardiac afterload of thoracic aortic clamping, preserve visceral, renal, and lower-extremity perfusion, and reduce spinal cord ischemia, a right axillofemoral bypass was performed before TAA resection. Patients and methods : Fifteen patients undergoing repair of their TAA had a preliminary axillofemoral bypass with an 8- to 10-mm externally supported polytetrafluoroethylene graft. Nine underwent elective repair and 6 were operated on emergently. All but 2 patients (both had type IV aneurysms) had spinal fluid drainage and all had moderate hypothermia induced (31°C to 32°C). All visible intercostal arteries were reimplanted. Results : Requirements for pharmacologic afterload reduction were minimal. Urine output was preserved during proximal aortic and intercostal anastomoses, and acidosis was minimal. Anticoagulation was not necessary unless the aortic bifurcation was replaced, and no patient had thrombotic complications. One (7%) patient died after repair of a ruptured aneurysm, and 1 (7%) developed paraplegia and required temporary dialysis. Conclusion : Preliminary axillofemoral bypass avoids the profound hemodynamic and physiologic derangement caused by clamping of the thoracic aorta, and effectively reduces the morbidity of TAA repair.
A manganese porphyrin superoxide dismutase mimetic enhances tumor radioresponsiveness.

Purpose: To determine the effect of the superoxide dismutase mimetic Mn(III) tetrakis(N-ethylpyridinium-2-yl)porphyrin (MnTE-2-PyP{sup 5+}) on tumor radioresponsiveness. Methods and Materials: Various rodent tumor (4T1, R3230, B16) and endothelial (SVEC) cell lines were exposed to MnTE-2-PyP{sup 5+} and assayed for viability and radiosensitivity in vitro. Next, tumors were treated with radiation and MnTE-2-PyP{sup 5+} in vivo, and the effects on tumor growth and vascularity were monitored. Results: In vitro, MnTE-2-PyP{sup 5+} was not significantly cytotoxic. However, at concentrations as low as 2 {mu}mol/L it caused 100% inhibition of secretion by tumor cells of cytokines protective of irradiated endothelial cells. In vivo, combined treatment with radiation and MnTE-2-PyP{sup 5+} achieved synergistic tumor devascularization, reducing vascular density by 78.7% within 72 h of radiotherapy (p < 0.05 vs. radiation or drug alone). Co-treatment of tumors also resulted in synergistic antitumor effects, extending tumor growth delay by 9 days (p < 0.01). Conclusions: These studies support the conclusion that MnTE-2-PyP{sup 5+}, which has been shown to protect normal tissues from radiation injury, can also improve tumor control through augmenting radiation-induced damage to the tumor vasculature.
Marriage, widowhood, divorce and HIV risks among women in sub-Saharan Africa

Objective: Studies on associations between marriage and HIV infection among women in sub-Saharan Africa are generally inconclusive. Not enough is known about HIV risks among divorced and widowed women. This study examined the relationship between marital status and HIV infection among women in seven sub-Saharan African countries. Methods: Retrospective data from the Demographic and Health Surveys were combined with HIV biomarker data from the AIDS Indicator Survey (AIS) for analysis. Random-effects complementary log-log models were applied to examine the relationship between marital status and HIV risks controlling for theoretically relevant covariates. Findings: Compared to never-married women widowed women were significantly more likely to be HIV positive. Similarly married women were more likely to be infected with HIV compared to never-married women in Lesotho and Zimbabwe. In Tanzania and Zimbabwe divorced women had higher risks of HIV infection compared to never-married women. Conclusion: Findings suggest that specific HIV programs be directed at vulnerable women in particular those widowed. Similar programs are needed for both poorer and wealthier women.
Survival in allosensitized children after listing for cardiac transplantation.

Background Little is known about the effect of pre-transplant alloantibody in the pediatric cardiac transplant population. Methods All cardiac listings ( n = 298) at Children's Hospital of Pittsburgh from January 1990 through February 2006 were reviewed to determine the impact of allosensitization on transplantation outcomes. Analysis focused on: (1) wait list outcomes; (2) survival from the time of listing, regardless of subsequent transplantation; (3) post-transplant graft and patient survival; and (4) post-transplant freedom from graft vasculopathy. Institutional policy required a negative, prospective crossmatch for candidates with panel-reactive antibody >20%. Results Alloantibody data were available for 252 (85%) listings. Median time to transplantation was greater for sensitized vs non-sensitized subjects (2.7 months vs 1.3 months; p = 0.02). At 1 year after listing, sensitized subjects had a higher incidence of death (22% vs 8.4%; p = 0.055). Survival at all time-points after listing (regardless of transplantation) was worse for sensitized subjects ( p = 0.04). Although no statistically significant differences in post-transplant graft or patient survival were noted, pre-transplant allosensitization was associated with decreased freedom from graft vasculopathy (hazard ratio [HR] 2.76, 95% confidence interval [CI] 1.18 to 6.45; p = 0.019). Conclusions A policy requiring a negative, prospective crossmatch for highly sensitized candidates is associated with longer wait list time and higher mortality after listing. The development of graft vasculopathy appears to be influenced by the presence of pre-transplant alloantibody.
Hypovitaminosis C and cholelithiasis in guinea pigs

Summary Hypovitaminotic C guinea pigs fed a high cholesterol diet for 5 weeks developed gallstones (81% cholesterol by weight), whereas no concretements were observed in vitamin C replete animals fed the same diet. Gallstone formation was associated with qualitative changes in the gallbladder bile, namely, a higher cholesterol concentration, a lowered bile acid content, and diminished phospholipid: cholesterol and bile acid: cholesterol ratios. No differences in 7α-ketolithocholic acid levels between groups was observed, but the chronic hypovitaminotic C animals had significantly lower levels of chenodeoxycholic acid. It is concluded that in the chronically hypotivaminotic C guinea pig there is a reduction in gallbladder bile acid: cholesterol and phospholipid; cholesterol ratios arising from an impaired conversion of cholesterol to chenodeoxycholic acid, and that consequently cholesterol precipitation and gallstone formation are favoured.
Sequential interaction in depression: Effects of depressive behavior on spousal aggression

The present study was designed to examine patterns of interaction which may be uniquely associated with depressed-discordant couples. Accordingly, the behavior of depressed-discordant couples was contrasted with the behavior of nondepressed-discordant couples, and nondepressed-nondiscordant community couples. Codes were collapsed to follow Biglan et al.'s (1985) proposed categories of aggressive, facilitative, and depressive behavior. Elevated rates of depressive behavior were found only for wives diagnosed as depressed. An examination of conditional responding at Lag 1 indicated that the groups differed in the extent to which wife depressive behavior suppressed husband aggressive behavior, with the greatest suppression effect occurring in the nondepressed-discordant group. Follow-up analyses indicated that the length of marital discord was strongly correlated with the magnitude of the suppression effect in both discordant groups. The longer the duration of marital discord, the less the suppression of spousal aggression by depressive behavior. The results suggest that depressive behavior may suppress aggressive behavior early in the course of marital discord, and become less efficacious in the context of prolonged marital discord regardless of diagnostic status.
Affect versus evaluation in the structure of attitudes

Abstract A distinction is made between affect and evaluation in the structure of attitudes. Affect refers to emotional responses and feelings engendered by an attitude object. Evaluation refers to thoughts, beliefs, and judgments about an attitude object. In Study 1, multiple measures of affect and evaluation were collected in six attitude domains. Estimates of the disattenuated correlation between affect and evaluation varied from .25 to .89, supporting discriminant validity of the distinction. Affect and evaluation were both correlated with a global measure of attitude, even when the effects of one were partialled from the other. Study 2 focused on the attitude domain of blood donation. The disattenuated correlation between affect and evaluation was .52. Affect, but not evaluation, was correlated with independent measures of mood. Self-reported behaviors relating to blood donation were more strongly related to affect than to evaluation. However, the relationship between affect and behavior diminished with increasing experience in donating blood. These results have important implications for theories of attitude structure, techniques of attitude measurement, and studies of attitude change and the attitude-behavior relationship.
The Interrelationship of Measures of Locus of Control, Intelligence, and Achievement in Juvenile Delinquents.

To test the reported relationship between locus of control and academic achievement, the Children's Nowicki-Strickland Internal-External scale, the Peabody Individual Achievement Test, and the Wechsler Intelligence Scale for Children were administered to 45 male juvenile delinquents. All intercorrelations between the three tests were positive and significant. Subjects were then divided into three groups on the basis of their locus of control scores and analyses of variance and covariance were performed. These analyses revealed that, with the effects due to IQ partialed out, achievement did not significantly vary for the different levels of locus of control. Results were discussed as being non-supportive of previous research and indicative of greater specificity in the delineation of the locus of control/academic achievement relationship.
Framed Round-Robin Arbitration with Explicit Feedback Control for Combined Input-Crosspoint Buffered Packet Switches

This paper introduces a frame-based round-robin arbitration scheme with explicit feedback control (FRE) for combined input-crosspoint buffered packet switches. We consider a CICB switch with fixed-length packets, called cells. The proposed scheme dynamically sets the frame size according to the amount of cell accumulation at the input queues. We study FRE when applied to a continuous system. We transport the FRE concept into a discrete system as an arbitration scheme for a packet switch, and study the switching performance. We combine FRE, which is used as the input arbitration scheme, with other round-robin based schemes, used as output arbitration schemes. The resulting combined schemes provide high throughput under several admissible traffic patterns when used in a switch with one-cell crosspoint buffers and no speedup.
Scholarships and supports available to foster care alumni: A study of 12 programs across the US

Abstract Postsecondary education remains unattainable for many foster care alumni. This can be attributed to many factors including inadequate academic preparation, and a lack of financial, housing and supportive services available to college students from foster care. This exploratory study gathers qualitative data from twelve college programs nationwide that provide scholarship and supportive services to foster care alumni attending postsecondary education. Findings illustrate six major themes of youth's unmet needs: academic preparation; housing; financial assistance; the need for emergency assistance; youth's personal challenges; and, the need for advocacy. Program coordinators state the importance of accessibility, advocacy, academic supports in the form of tutoring and mentoring; assistance in finding housing; scholarships; emergency financial assistance; access to health and mental health providers; and, outreach programs to college bound foster youth. Recommendations explore furthering tuition waiver programs and supportive services that address the emotional, financial and housing needs of foster care alumni attending college.
Modulation of Meningeal Nociceptors Mechanosensitivity by Peripheral Proteinase-Activated Receptor-2: The Role of Mast Cells

Inflammatory-related activation and sensitization of meningeal nociceptors is believed to play a key role in promoting the intracranial throbbing pain of migraine. We have shown recently that mast cell activation and various mast cell-derived inflammatory mediators can promote activation and sensitization of meningeal nociceptors. Mast cell tryptase has also been proposed to promote pain hypersensitivity by activating the proteinase-activated receptor 2 (PAR2) that is expressed on nociceptive neurons. In this study using in vivo single-unit recording in the trigeminal ganglion of anaesthetized rats, we found that local meningeal activation of PAR2 using the specific agonist SLIGRL-NH2 promoted sensitization of the threshold response while provoking desensitization of the suprathreshold responses. SLIGRL-NH2 also excited a subpopulation of meningeal nociceptors. Chronic mast cell depletion enhanced the sensitizing effects of PAR2 activation while curbing its desensitizing effects. Mast cell depletion did not change the PAR2-mediated excitatory effect. We propose that by enhancing the mechanical sensitivity of meningeal nociceptors local PAR2 activation could play a role in promoting the throbbing pain of migraine and that local mast cell degranulation may modulate such an effect.
Surface Ionization Ion Sources

Recent achievements with iridium surface ionization ion sources are discussed. These sources can be used to produce ion beams of elements with ionization potentials from 5-1/2 to 6 V, e. g., the IILA metals (Al, Ga, In and Tl), the rare earths, the heavier alkaline earths, and Li, in addition to the usual heavier alkalis. Ion beams of Li, Al, Ga, and In have been produced here. Ionization efficiencies, critical temperatures, current densities, and beam purities as measured by magnetic mass separation are discussed. An ion source design being employed for the IIIA metals is described briefly.
Developmental Family Processes and Interparental Conflict: Patterns of Microlevel Influences

Although there are frequent calls for the study of effects of children on families and mutual influence processes within families, little empirical progress has been made. We address these questions at the level of microprocesses during marital conflict, including children's influence on marital conflict and parents' influence on each other. Participants were 111 cohabiting couples with a child (55 male, 56 female) age 8-16 years. Data were drawn from parents' diary reports of interparental conflict over 15 days and were analyzed with dynamic systems modeling tools. Child emotions and behavior during conflicts were associated with interparental positivity, negativity, and resolution at the end of the same conflicts. For example, children's agentic behavior was associated with more marital conflict resolution, whereas child negativity was linked with more marital negativity. Regarding parents' influence on each other, among the findings, husbands' and wives' influence on themselves from one conflict to the next was indicated, and total number of conflicts predicted greater influence of wives' positivity on husbands' positivity. Contributions of these findings to the understanding of developmental family processes are discussed, including implications for advanced understanding of interrelations between child and adult functioning and development.
Temperature effect on affinity chromatography of two lectins from the seeds of Ricinus communis

Specific adsorption capacity of Sepharose 4B in affinity chromatography for two purified galactose-binding lectins, designated as III/sub L/ and III/sub H/, from the seed of Ricinus communis (castor bean) was measured from 7 to 24/sup 0/C. The adsorption coefficients for these two protein fractions as a function of temperature were also obtained. It was found that there is a characteristic transition of adsorption coefficient at 18/sup 0/C for both lectins. Adsorption coefficients between Sepharose 4B and these two lectins were also expressed in terms of ..delta..G, ..delta..H, and ..delta..S. It is suggested that the difference in the temperature dependence of the binding energy of these two lectins may be used for their separation at selected temperature.