cssi/SciSciGPT-SciSciNet huggingface dataset:
Lung Epithelial Cell (A549) Interaction with Unopsonized Environmental Particulates: Quantitation of Particle-Specific Binding and IL-8 Production

The A549 cell line was used to model in vitro the interaction of alveolar epithelium with environmental particulates. Confocal and electron microscopy demonstrated A549 binding and internalization of titanium dioxide (TiO2), iron oxide (Fe2O3), concentrated ambient air particulates (CAPs), and the fibrogenic particle alpha-quartz. Flow cytometry allowed quantitation of particle binding by measuring increased right angle light scatter (RAS) (TiO2) [40 micrograms/mL], Fe2O3 [100 micrograms/mL], alpha-quartz [200 micrograms/mL], or CAPs [40 micrograms/mL] fold increase RAS: 8.1 +/- 0.9, 4.3 +/- 0.4, 2 +/- 0.1, 1.6 +/- 0.1, respectively). With this quantitative assay, binding of particle was found to be calcium-dependent for TiO2 and Fe2O3 (% inhibition, 61.0 +/- 1.9, 40.0 +/- 5.6, respectively), while alpha-quartz binding was calcium-independent. A panel of polyanionic ligands known to inhibit scavenger-type receptors was used to identify binding mechanisms for environmental particulates. Both heparin and polyinosinic acid (polyI), but not the control polyanion chondroitin sulfate, caused marked inhibition of particulate binding by A549 cells (e.g., TiO2 [40 micrograms/mL] binding; polyI, heparin, and chondroitin sulfate: 73.8 +/- 3.5, 75.5 +/- 6.0, 7.5 +/- 6.7% inhibition, respectively; mean +/- SE, n > or = 4), indicating that scavenger receptor(s), albeit those distinct from the heparin-insensitive acetylated-LDL receptor, mediate particulate binding. The particulates ability to stimulate interleukin (IL-8) production in A549 cells was also tested. alpha-quartz, but not TiO2 or CAPs, caused a dose-dependent production of IL-8 (range 1-6 ng/mL), demonstrating a particle-specific spectrum of epithelial cell cytokine (IL-8) response. The results suggest that lung epithelial cell interaction with environmental particles is mediated by distinct receptors and can lead to particle dependent cytokine responses.
Who Cares About Being Gentle? The Impact of Social Identity and the Gender of One's Friends on Children's Display of Same-Gender Favoritism

This research assessed children’s same-gender favoritism by examining whether children value traits descriptive of their own gender more than traits descriptive of the other gender. We also investigated whether children’s proportion of same-gender friends relates to their same-gender favoritism. Eighty-one third and fourth grade children from the Midwest and West Coast of the U.S. rated how well 19 personality traits describe boys and girls, and how important each trait is for their gender to possess. Results replicate and extend past trait assignment research by demonstrating that both genders valued same-gender traits significantly more than other-gender traits. Results also indicated that boys with many same-gender friends derogated feminine-stereotyped traits, which has implications for research on masculinity norms within male-dominated peer groups.
Selenium Supplementation Alters Gene Expression Profiles Associated with Innate Immunity in Whole-Blood Neutrophils of Sheep

Footrot (FR) is a common, contagious bacterial disease of sheep that results in lameness and significant economic losses for producers. We previously reported that sheep affected with FR have lower whole-blood (WB) selenium (Se) concentrations and that Se supplementation in conjunction with routine control practices accelerates recovery from FR. To determine whether oral Se-yeast administered at supranutritional levels (>4.9 mg Se/week) alters the ability of sheep to resist or recover from FR infection, 60 ewes with and 60 ewes without FR were drenched once weekly for 62.5 weeks with 0, 4.9, 14.7, or 24.5 mg organic Se-yeast (30 ewes per treatment group). Footrot prevalence and severity were measured at 0, 20, 28, 40, and 60 weeks of Se supplementation. Genomic expression of eight WB-neutrophil genes for selenoproteins and seven WB-neutrophil genes for proteins involved in innate immunity was determined at the end of the treatment period using SYBR Green and quantitative polymerase chain reaction methodology. Supranutritional Se-yeast supplementation successfully increased Se status in sheep but did not prevent FR. Supranutritional Se-yeast supplementation increased WB-neutrophil expression of genes involved in innate immunity: l-selectin, interleukin-8 receptor, and toll-like receptor 4, which were or tended to be lower in ewes affected with FR. Furthermore, supranutritional Se-yeast supplementation altered the expression of selenoprotein genes involved in innate immunity, increasing selenoprotein S and glutathione peroxidase 4 and decreasing iodothyronine deiodinases 2 and 3. In conclusion, supranutritional Se-yeast supplementation does not prevent FR, but does alter WB-neutrophil gene expression profiles associated with innate immunity, including reversing those impacted by FR.
The coupling of a large amplitude collective motion to RPA excitations

Abstract Adiabatic large amplitude motion along a path of minimal potential energy is shown to be coupled to residual modes of excitation. These are described by RPA modes denned at every point q of the adiabatic path. A semi-classical Hamiltonian for this system is constructed, which exhibits the coupling terms between the two types of modes.
TU‐D‐204B‐07: Correction for the ‘Black Hole’ Artifact in Cone‐Beam Computed Tomography

Purpose: An artifact typically seen in axial cone‐beam computed tomography(CBCT) reconstructions is a dark region or ‘black hole’ situated beneath the scan isocenter. We have traced the cause of the artifact to scattered radiation coming from the patient table. The artifact is most severe for offset‐detector scans and is especially significant in image‐guidedradiotherapy(IGRT) where patient tables have flat tops and are larger than those used for diagnostic radiology. To address this problem, we have developed a hybrid scatter kernel superposition (SKS) method designed to correct for scatter from both the object‐of‐interest and the patient table. Method and Materials: The proposed algorithm uses separate kernels to estimate scatter from the patient table and the object‐of‐interest. For each projection image, the location of the shadow cast by the patient table on the imager is determined. The region not shadowed by the table is processed using asymmetric kernels that best model scatter transport through body‐like objects. The patient table region is processed using a combination of the asymmetric kernels and slab‐derived symmetric kernels. The composition of these hybrid kernels is projection‐angle dependent. To test the algorithm, pelvis phantom and patient data were acquired using the Varian On‐Board Imager (OBI) and processed. Artifact intensities and HU accuracies were assessed. Results: The hybrid kernel algorithm produced substantially better scatter estimates than previous SKS methods. HU non‐uniformities in the pelvis phantom were reduced from 97HU to 29HU. In the in vivo scan, the black hole artifact was reduced by 128HU and anatomical details were made more visible. Conclusions:Radiotherapy patient tables can produce significant scatter‐related artifacts. The proposed hybrid SKS algorithm effectively addresses this problem. Scatter from both the object‐of‐interest and the patient table was accurately estimated, and image uniformity and HU accuracy were greatly improved. Employees of Varian Medical Systems.
An estimate of the nearest neighbor base-pair content of 5S RNA using CD and absorption spectroscopy.

We analyzed the CD and uv absorption spectra of 5S RNA from Escherichia coli using the method developed in the preceding paper. The analysis of spectra of 5S RNA at 20 degrees C in 0.1M NaClO4, 2.5 mM Na+ (phosphate), pH 7.0, and 0.5 mM MgSO4 gave 7 +/- 3.6 A.U base pairs, 25 +/- 3.6 G.C base pairs, and 7.5 +/- 3.6 G.U base pairs. Estimates of nearest neighbor base pairs were more consistent with the Pieler-Erdmann and the Gewirth-Moore secondary structure models than with the Fox-Woese or the Burns-Luoma-Marshall models. We also examined the structure of 5S RNA as a function of temperature. The melting profile exhibited two transitions--one at about 35 degrees C and one above 50 degrees C. Our spectral data showed that helices I and II were stable during the first transition, and agreed with other data that helix III was the most likely helix to have melted. The results from this in-depth study of 5S RNA indicate that our method of analysis should be useful for studying the secondary structures of other small, unmodified RNAs.
Pharmacoeconomic considerations with statin therapy

Statins have been shown to reduce morbidity and mortality in patients with and without coronary heart disease, and in patients with elevated and normal or average cholesterol levels. Economic evaluations of these mortality trials have demonstrated statins to be cost-effective. As these trials were placebo comparisons, their results are now of limited use in guiding the drug therapy selection process. The more relevant questions today are focused on ways of optimising statin therapy. More recent studies have found that more intensive statin therapy, using high doses of these agents that produce substantially greater reductions in low-density lipoprotein cholesterol, are associated with greater benefit than less intensive statin therapy. These trials suggest that statins with greater efficacy in reducing low-density lipoprotein cholesterol, would be preferred over less effective statins. So far, economic analyses of these comparative studies have not been published. These economic studies are needed to support formulary and drug therapy selection decisions regarding statins.
The Molecular Basis of Phospholipase D2-Induced Chemotaxis: Elucidation of Differential Pathways in Macrophages and Fibroblasts

We report the molecular mechanisms that underlie chemotaxis of macrophages and cell migration of fibroblasts, cells that are essential during the body's innate immune response and during wound repair, respectively. Silencing of phospholipase D1 (PLD1) and PLD2 reduced cell migration (both chemokinesis and chemotaxis) by approximately 60% and >80%, respectively; this migration was restored by cell transfection with PLD2 constructs refractory to small interfering RNA (siRNA). Cells overexpressing active phospholipase D1 (PLD1) but, mostly, active PLD2 exhibited cell migration capabilities that were elevated over those elicited by chemoattractants alone. The mechanism for this enhancement is complex. It involves two pathways: one that is dependent on the activity of the lipase (and signals through its product, phosphatidic acid [PA]) and another that involves protein-protein interactions. The first is evidenced by partial abrogation of chemotaxis with lipase activity-defective constructs (PLD2-K758R) and by n-butanol treatment of cells. The second is evidenced by PLD association with the growth factor receptor-bound protein 2 (Grb2) through residue Y(169), located within a Src homology 2 (SH2) consensus site. The association Grb2-PLD2 could be visualized by fluorescence microscopy in RAW/LR5 macrophages concentrated in actin-rich membrane ruffles, making possible that Grb2 serves as a docking or intermediary protein. The Grb2/PLD2-mediated chemotaxis process also depends on Grb2's ability to recognize other motility proteins, like the Wiskott-Aldrich syndrome protein (WASP). Cell transfection with WASP, PLD2, and Grb2 constructs yields the highest levels of cell migration response, particularly in a macrophage cell line (RAW/LR5) and only modestly in the fibroblast cell line COS-7. Further, RAW/LR5 macrophages utilize for cell migration an additional pathway that involves S6 kinase (S6K) through PLD2-Y(296), known to be phosphorylated by epidermal growth factor receptor (EGFR) kinase. Thus, both fibroblasts and macrophages use activity-dependent and activity-independent signaling mechanisms. However, highly mobile cells like macrophages use all signaling machinery available to them to accomplish their required function in rapid immune response, which sets them apart from fibroblasts, cells normally nonmobile that are only briefly involved in wound healing.
My Patients Have THAT in Their Mouths? Identifying Patients at Risk for Pneumonia

Abstract BACKGROUND: Processes that identify and reduce patient risk for nosocomial infections will be essential for compliance with the Joint Commission on Accreditation of Healthcare Organization's National Patient Safety Goal #7 and Standards. The prevention of pneumonia through oral care interventions is being explored to reduce oropharyngeal and dental plaque colonization as a risk factor, especially in the intubated, mechanically ventilated (MV) patient. The objective of this study was to describe colonization rates in the first 24 hours of patients placed on MV. METHODS: Patients were randomly selected for dental plaque and/or pharyngeal cultures in eight ICUs across five hospitals from December 2002 through August 2003. Specimens were serially diluted to obtain quantitative colony counts. Potential respiratory pathogens (PRP) were identified through standard microbiological identification methods. RESULTS: Fifty patients were cultured from 2621 patients placed on MV. Sixty-six percent of the patients were colonized with PRP. The most frequently isolated pathogen was Staphylococcus aureus (66%), with 64% of those isolates being methicillin-resistant. The other potentially antibiotic-resistant organisms were Enterobacter 24%, Pseudomonas (9%), and Acinetobacter (3%). CONCLUSIONS: The high rate of colonization of intubated MV patients at less than 24 hours indicates that this population is already colonized prior to intubation and at increased risk for tracheal colonization or aspiration of potential respiratory pathogens during the intubation procedure. Efforts targeting preventive oral interventions like mechanical cleansing, the removal of dental plaque by toothbrushing, and/or the use of an antimicrobial oral rinse reducing bacterial load may prevent or reverse colonization.
A Task Duplication Based Scalable Scheduling Algorithm for Distributed Memory Systems

One of the major limitations of distributed memory systems (DMSs) is the high cost for interprocessor communication, which can be minimized by having an efficient task partitioning and scheduling algorithm. It is well known that scheduling the tasks of a directed acyclic graph (DAG) to obtain an optimal solution is a strong NP-hard problem. This paper presents a scalable task duplication based scheduling (STDS) algorithm which can schedule the tasks of a DAG onto the processors of a DMS with a worst case complexity ofO(|V|2), where |V| is the number of nodes of the DAG. This algorithm generates an optimal schedule for DAGs provided a cost relationship is satisfied and if the required number of processors are available. The STDS algorithm generates a schedule for the number of processors available in the system. The performance of the STDS algorithm has been observed by comparing the parallel execution times for practical DAGs with the theoretical lowerbound.
Differential scanning calorimetry of milk fat globule membranes

Differential scanning calorimetry was employed as an aid in examining the structure of the bovine milk fat globule membrane. At least six major endotherms are observed between 10 and 90 degree C, corresponding to order-disorder transitions of discrete structural domains of the membrane. These endothermic transitions occur at 16, 28, 43, 58, 68, and 75 degrees C. The transitions occurring between 10 and 50 degrees C were reversible, suggesting the involvement of lipid. However, the high temperature transitions were irreversible. The calorimetric C transition, center at 43 degree C, was shown to involve neutral lipid, since the endotherm was reversible, insensitive to proteolysis, and similar to the endotherm of the isolated neutral lipid fraction of the milk fat globule membrane. The glycolipid and phospholipid fractions of the milk fat globule membrane yielded endotherms outside of the temperature range of the C transition. Another endotherm, the D transition (58 degree C), was found to involve the denaturation of the major membrane coat protein, butyrophilin (band 12). Evidence for this assignment included the following observations: (i) the nearly selective proteolysis of butyrophilin resulted in the complete removal of the D transition, (ii) the butyrophilin-enriched, Triton X-100-insoluble pellet of milk fat globule membrane yielded a relatively normal D transition, and (iii) the irreversible, disulfide-stabilized aggregation of butyrophilin occurred in the membrane solely at the temperature of the D transition. Furthermore, no other prominent milk fat globule membrane polypeptide formed these non-native disulfide crossbridges during the D transition. The sources of the other major endotherms of the milk fat globule membrane have not yet been assigned.
QoS support for end users of I/O-intensive applications using shared storage systems

While the performance of compute-bound applications can be effectively guaranteed with techniques such as space sharing or QoS-aware process scheduling, it remains a challenge to meet QoS requirements for end users of I/O-intensive applications using shared storage systems because of the difficulty of differentiating I/O services for different applications with individual quality requirements. Furthermore, it is difficult for end users to accurately specify performance goals to the storage system using I/O-related metrics such as request latency or throughput. As access patterns, request rates, and the system workload change in time, a fixed I/O performance goal, such as bounds on throughput or latency, can be expensive to achieve and may not provide performance guarantees such as bounded program execution time. We propose a scheme supporting end-users' QoS goals, specified in terms of program execution time, in shared storage environments. We automatically translate the users' performance goals into instantaneous I/O throughput bounds using a machine learning technique, and use dynamically determined service time windows to efficiently meet the throughput bounds. We have implemented this scheme in the PVFS2 parallel file system and have conducted an extensive evaluation. Our results show that this scheme can satisfy realistic end-user QoS requirements by making highly efficient use of the I/O resources. The scheme seeks to balance programs' attainment of QoS requirements, and saves as much of the remaining I/O capacity as possible for best-effort programs.
Treatment practices of FSGS among North American pediatric nephrologists

A survey of North American pediatric nephrologists was conducted to assess the variability in the treatment of primary steroid-resistant focal segmental glomerulosclerosis (FSGS) of native kidneys. The most widely used immunosuppressive drug was cyclosporin A, with 73.9% using it often or sometimes. Only 44.3% used intravenous methylprednisolone combined with an alkylating agent at least sometimes; the use of methylprednisolone without cytotoxic drugs was slightly more common. Prolonged oral steroid therapy (>3 months) was used often or sometimes by 50.3%. The use of angiotensin converting enzyme inhibitors was very common, while lipid-lowering agents were rarely used. The variablity in the treatment of FSGS most likely results from lack of evidence-based information and underscores the need for controlled pediatric multicenter treatment trials.
Genetic and parent-of-origin influences on X chromosome choice in Xce heterozygous mice

X chromosome inactivation is unique among dosage compensation mechanisms in that the two X chromosomes in females are treated differently within the same cell; one X chromosome is stably silenced while the other remains active. It is widely believed that, when X inactivation is initiated, each cell makes a random choice of which X chromosome will be silenced. In mice, only one genetic locus, the X-linked X controlling element (Xce), is known to influence this choice, because animals that are heterozygous at Xce have X-inactivation patterns that differ markedly from a mean of 0.50. To document other genetic and epigenetic influences on choice, we have performed a population-based study of the effect of Xce genotype on X-inactivation patterns. In B6CAST F1 females (Xce b /Xce c ), the X-inactivation pattern followed a symmetric distribution with a mean of 0.29 (SD = 0.08). Surprisingly, however, in a population of Xce b /Xce c heterozygous B6CAST F2 females, we observed significant differences in both the mean (p = 0.004) and variance (p = 0.004) of the X-inactivation patterns. This finding is incompatible with a single-locus model and suggests that additional genetic factors also influence X chromosome choice. We show that both parent-of-origin and naturally occurring genetic variation at autosomal loci contribute to these differences. Taken together, these data reveal further genetic complexity in this epigenetic control pathway.
The Signal Separator with a Moving Platform

It is shown for the Signal Separator antijamming algorithm that the output signal(s) are invariant with receive-platform attitude in the case of three orthonormal cosine-magnitude antenna-gain patterns. Hence, this AJ Technique requires no external attitude stabilization in this case.
Superconductor strip response to a normally incident magnetic field

Abstract The response of an infinitely long superconductor strip in its virgin state to a normally incident magnetic field is calculated. The non-divergent, analytic expressions for the screening current and magnetic field apply for a strip of arbitrary width and thickness. For a high aspect-ratio strip, the calculated surface induction and screening current spatial distribution compares well with the corresponding expressions obtained from the commonly employed (canonical) expression, provided the evaluation point is not close to the strip edges. The new expression predicts for the total screening-current a value which exceeds that obtained from the canonical expression by a factor of 5–8 and is highly peaked at the strip edges.
The Development of Tolerance to the Anticonvulsant Effect of Phenobarbital in Mice

Summary: The development of tolerance to the anticonvulsant effect of chronically administered phenobarbital was demonstrated in miee by the maximal electroshock (MES) test. Anticonvulsant activity decreased 50% over a 5 day period. Brain and plasma levels of phenobarbital measured 2 hr after a 25 mg/kg dose of phenobarbital were the same between days 1 and 5, indicating that distributional or pharmacokinetic parameters were not involved. The loss of anticonvulsant activity of phenobarbital is primarily related to the drug's effect to prevent the spread of MES-induced epileptic neuronal activity. In contrast, the anticonvulsant action of phenobarbital on seizure threshold, as measured by the minimal electroshock seizure threshold (EST) test, and on the spread of epileptic discharge induced by pentylenetetrazol (PTZ), as evaluated by the PTZ infusion test, remained unchanged. RESUME Le developpement d'une tolerance a Taction anti-convulsivante du phenobarbital (PB) administre de facon chronique peut etre demontre chez la souris par le test de l'electro-choc maximum (MES). l'activite anti-convulsivante decroit de 50% sur une periode de 5 jours. Les taux plasmatique et cerebral de PB mesures 2 heures apres administration de 25 mg/kg du produit sont les memes entre les jours 1 et 5, ce qui indique que les parametres concernant la distribution, ou la pharmacocinetique ne sont pas impliques dans le processus de tolerance. La perte d'activite anti-convulsivante du PB est essentiellement en relation avec la possibilitye du produit a prevenir la propagation de l'activite neuronique epileptique induite par le MES. Au contraire. Taction anti-convulsivante du PB sur le seuil critique, tel qu'il est mesure par le test de l'electro-choc minimum, et sur la propagation de la decharge epileptique induite parle pentylenetetrazol, demeure inchingee. RESUMEN Se demostro que la administracion cronica de fenobarbital produce un acostumbramiento en su capacidad anticomicial en ratones sometidos a la prueba de electroshock maximo (MES). La actividad anticonvulsivante disminuyo en un 50% en un periodo de 5 dias. Los niveles cerebrales y plasmaticos de fenobarbital medidos 2 horas despues de la administration de una dosis de 25 mg/kg de peso no cambiaron entre los dias 1 y 5, indicando que los parametros far-macocineticos y de distribution no estaban involu-crados. La perdida de capacidad anticomicial del fenobarbital se relaciona, sobre todo, con el efecto del farmaco para prevenir la difusion de actividad neuronal inducida por el MES. Por el contrario, la ac-cion del fenobarbital en el umbral convulsivante (tal como se mide por medio de la prueba del “minimo umbral de electroshock inductor de crisis” -EST-) y de la difusion de la descarga epileptica inducida por el pentilentetrazol (PTZ), usando la prueba de infusion, no se vieron modificadas.
Heterologous expression of the P450 sterol 14α-demethylase gene from Monilinia fructicola reduces sensitivity to some but not all DMI fungicides☆

Abstract The cytochrome P450 sterol 14α-demethylase gene (MfCYP51) from Monilinia fructicola (G. Wint.) Honey was cloned and sequenced. The gene was 1680 bp in length (including introns) and was predicted to have two introns of 54 and 57 bp. The nucleotide sequence was 82.1, 53.4, 47.1, 45.1, and 33.6% and the amino acid sequence was 89.7, 76.1, 76.1, 71.8, and 66.9% identical to the CYP51 genes from Botrytis cinerea, Tapesia yallundae, T. acuformis, Erysiphe graminis, and Uncinula necator, respectively. Expression of MfCYP51 in PDR5::TN5 deficient Saccharomyces cerevisiae resulted in reduced sensitivity of the yeast transformants to myclobutanil but not to propiconazole, fenbuconazole or tebuconazole. A wildtype population of 33 M. fructicola isolates was significantly less sensitive to myclobutanil than to propiconazole, fenbuconazole, and tebuconazole. The sensitivity of the isolates to myclobutanil and the three other DMI fungicides included in this study was correlated positively, suggesting a similar or identical mode of action. The low sensitivity in M. fructicola wildtype isolates to myclobutanil could result from a less effective binding potential of the fungicide to the 14α-demethylase.
Principle of Salvage: A Mischaracterization of Military Medicine

Michael Gross (2008) argues that a fundamental difference between military medical ethics and medical ethics in general is that military medicine is driven by the principle of salvage, which priori...
Gender differences in labor market wages: A comparison of industrial sector effects and a decomposition within four occupations

Abstract Women earn less than men. The reason may be due to either industrial segmentation or occupational segregation or both according to the current research. Researches focusing on one structure tend to neglect the other or to use an inadequate representation. This article examines the simultaneous impact of industrial sector and gender on imputed wages with labor force incumbents in four detailed occupations. These occupations are from a set identified as relatively internally homogeneous on measures of task performed from the Dictionary of Occupational Titles . Thus, within-occupational differences in work performed between males and females are minimized. The findings reinforce the importance of industrial sector for economic outcomes and demonstrate the value of an improved representation of occupation. The decomposition shows wage discrimination exists against females in each of these occupations, and in two sector-by-sector occupation comparisons, females should earn more than males.
Shifting the Paradigm: Training Undergraduate Students in Software Security

Computer software is typically developed according to software engineering methodologies. However, with the introduction of the Internet and the World Wide Web, protecting data has become a topic of importance. In order to protect data from hackers and saboteurs in a global society where e-commerce, ebusiness, and e-sharing are the “norm”, professionals should have sound knowledge in methods to protect data. Consequently, the area of information assurance (IA) has become one of great significance and it is important that the next generation of technologists are trained in development techniques that can ensure the confidentially and integrity of information. Traditionally, courses in secure software development are offered at the graduate level or in a stand-alone software security course at the undergraduate level. The aim of this paper is to present a paradigm for introducing software security to undergraduates in a traditionally taught software engineering course. The paper also presents challenges and future work.
Estrous cycle regulation of extrasynaptic δ-containing GABA(A) receptor-mediated tonic inhibition and limbic epileptogenesis.

The ovarian cycle affects susceptibility to behavioral and neurologic conditions. The molecular mechanisms underlying these changes are poorly understood. Deficits in cyclical fluctuations in steroid hormones and receptor plasticity play a central role in physiologic and pathophysiologic menstrual conditions. It has been suggested that synaptic GABAA receptors mediate phasic inhibition in the hippocampus and extrasynaptic receptors mediate tonic inhibition in the dentate gyrus. Here we report a novel role of extrasynaptic δ-containing GABAA receptors as crucial mediators of the estrous cycle–related changes in neuronal excitability in mice, with hippocampus subfield specificity. In molecular and immunofluorescence studies, a significant increase occurred in δ-subunit, but not α4- and γ2-subunits, in the dentate gyrus during diestrus. However, δ-subunit upregulation was not evident in the CA1 region. The δ-subunit expression was undiminished by age and ovariectomy and in mice lacking progesterone receptors, but it was significantly reduced by finasteride, a neurosteroid synthesis inhibitor. Electrophysiologic studies confirmed greater potentiation of GABA currents by progesterone-derived neurosteroid allopregnanolone in dissociated dentate gyrus granule cells in diestrus than in CA1 pyramidal cells. The baseline conductance and allopregnanolone potentiation of tonic currents in dentate granule cells from hippocampal slices were higher than in CA1 pyramidal cells. In behavioral studies, susceptibility to hippocampus kindling epileptogenesis was lower in mice during diestrus. These results demonstrate the estrous cycle–related plasticity of neurosteroid-sensitive, δ-containing GABAA receptors that mediate tonic inhibition and seizure susceptibility. These findings may provide novel insight on molecular cascades of menstrual disorders like catamenial epilepsy, premenstrual syndrome, and migraine.
1347 CONTINUOUS VERSUS INTERMITTENT HEPATIZATION OF UMBILICAL ARTERY CATHETERS

Previous studies have compared the rate of occlusion of umbilical artery catheters with and without heparin (Rajani, 1979; David, 1981). However, the difference between continuous infusion versus intermittent flushing with heparin has not been studied. We therefore designed a randomized controlled trial of continuous infusion vs. intermittent flushing in 47 infants who required umbilical artery catheters. Twenty-nine received cont. infusion with heparin (1 U/ml) and 18 received intermittent flushing with heparinized saline (1 U/ml). Ten infants weighed ≤1000 g, 19 weighed 1001-1800 g, and 18 weighed >1800 g. We recorded duration of patency, reason for removal, the number and severity of complications (blanching and cyanosis of legs), and clinical history. There were no significant differences in severity of disease, birth wt., birth wt. distribution, number or severity of complications, PT/PTT, size of catheter, glucose concentration, rate of infusion, or drugs. Seventy-six percent of patent catheters remained in place for more than 24 hours (range 8-167 hrs). All of the occlusions occurred in infants who weighed 1800 g. Our findings indicate that continuous heparin infusion is a better way of maintaining patency of an umbilical artery catheter.
Optimal and Near Optimal Price and Advertising Strategies for Finite and Infinite Horizons

The simplest price and advertising optimization model consistent with current empirical research is formulated and analyzed. An explicit horizon function is introduced to compare and synthesize the finite and infinite horizon situations. The practically prevalent procedure of setting this period's advertising expenditure proportional to the previous period's sales is, for good reasons, declared near optimal.
Ablation for Atrial Fibrillation Can We Decrease Thromboembolism Without Increasing the Risk for Bleeding

Stroke is one of the most feared untoward sequelae associated with atrial fibrillation (AF) ablation procedures, whereas bleeding is the most common.1,2 We typically explain to patients that intensive anticoagulation during ablation is necessary to decrease the likelihood of stroke, even though some increase in bleeding and vascular complications will occur. In the present issue of Circulation , Wazni et al3 report performing AF ablation in patients with a therapeutic International Normalized Ratio (INR) and successfully decreasing thromboembolism without increasing the risk of bleeding. Article p 2531 The hitherto standard approach taken by most ablationists is to discontinue Coumadin for 3 to 5 days before ablation and proceed after normalization of the INR. Although simple, 3 issues require attention with this approach. First, in the period when the patient is off warfarin to prevent thrombus formation, low molecular weight heparin is administered. This approach is generally successful because, when transesophageal and/or intracardiac echocardiography is performed just before left atrial ablation, only rarely is thrombus found. Second, a more difficult issue is reanticoagulation after ablation where there may be periods of inadequate anticoagulation, which allows thrombus to occur. Third, heparin used as a bridge postablation has a higher propensity to promote postprocedural bleeding than warfarin itself.4 Wazni et al suggest the solution of simply continuing warfarin and obviating the need to address the above problems.3 Does their approach allow the brinkmanship necessary to resolve this dilemma by simultaneously decreasing thrombotic and hemorrhagic risk, and should AF ablation be performed with a therapeutic INR? Let us first examine what approaches have been previously tried to achieve this desired result and …
A deterministic finite element analysis of the effects of projectile characteristics on the impact response of fully clamped flexible woven fabrics

Abstract In this paper the effects of projectile size and shape on the impact response of a single-layer fully-clamped flexible woven fabric are numerically studied using a finite element analysis. Six projectiles of spherical, cylindrical, and conical shapes with varying sizes but of the same mass are considered. A yarn-level fabric model with a deterministic implementation of experimental mean yarn tensile strength and inter-yarn friction is considered. A single impact velocity is chosen for the six different projectiles to compare the fabric impact responses in terms of residual projectile velocities, fabric energy dissipations, and number of failed yarns. Two impact locations are considered, at a yarn cross-over and at the gap in-between the yarns. The sensitivity of fabric impact response to projectile geometrical characteristics and impact location is demonstrated.
Oligopolistic pricing over the deterministic market demand cycle: some evidence from the US Portland cement industry

Abstract Haltiwanger and Harrington (1991) [Haltiwanger, J., Harrington, J.E. Jr., 1991. The impact of cyclical demand movements on collusive behavior. Rand Journal of Economics 22, 89–104.] formulated a theory of self-enforcing collusion assuming a deterministic demand cycle. They predicted that under a self-enforcing non-cooperative pricing scheme, for any level of demand, the price in the rising part of the cycle would always be greater than the price in the falling part of the cycle. They also predicted that the path of collusive profits should reach its peak before market demand. We test their predictions using data from the Portland cement industry. The hypotheses are tested using a multi-equation system, differentiating the boom and the bust periods from 1974 to 1989. The results support both of Haltiwanger and Harrington’s hypotheses.
A primer for applying service learning to computer science

Service learning is an educational philosophy that promotes active learning through community service. We have recently applied this approach in our computer science curriculum, specifically to our software engineering course. In order that other computer science departments can benefit from our experience, we have developed a primer one can follow to establish a program for service learning in the computer sciences. We also describe and assess our experience after one year of applying service learning to software engineering.
Chemical Information Instruction in Academe: Recent and Current Trends

As a continuation in a series about chemical information instruction in academe, this article describes the results of the 1993 survey of information instruction activities in 390 United States chemistry departments conducted by the American Chemical Society (ACS) Division of Chemical Information's Education Committee and makes comparisons with the previous 1984 survey. Current trends, especially in rapidly changing chemical resources, are indentified and resulting implications for information instruction programs are discussed. Ways of overcoming increasing costs of information resources are offered, as well as suggestions for involving faculty and librarians as active supporters and participants in such programs.
Substance use among pregnant adolescents: A comparison of self-reported use and provider perception

Purpose: This study describes, from both client and provider perspectives, the ethnic differences (African-American and white) in cigarette, alcohol, marijuana, and other drug (cocaine and crack) use among pregnant adolescents attending public prenatal clinics in one county. Methods: Client information was based on a cross-sectional survey of 248 consecutive adolescent, public prenatal clients. The sample represented 79% of pregnant adolescents in the country at the time of the study. Ethnic groups were compared through the use of appropriate bivariate statistics regarding (a) number, type(s), and frequency of substance(s) used; (b) mean age of first use; (c) change in use 6 months prior to pregnancy and first trimester; and (d) use among family and friends. Provider information was based on open-ended interviews among 23 individuals (91% of all providers) covering the same themes. Results: The majority of clients were African-American (61%), single (81%), and primaparous (72%). Many reportedly used at least one substance prior to pregnancy (79%) and during their first trimester (49%). The most common substances were cigarettes and alcohol. Overall, use of each substance during both time periods was higher among whites; yet African-Americans were more likely to report discontinued use. Substance use was common among adolescents' family members and friends. The provider survey revealed a wide range of perceptions about substance use among pregnant adolescents. Conclusions: Pregnant adolescents' self-reported substance use patterns differed by ethnicity, and providers' perceptions of substance use among their adolescent prenatal population differed from what was obtained from patients' self-reports. Additional research is needed to understand the role ethnicity plays in high-risk behaviors among adolescent prenatal clients, as well as its role in client—provider communication.
Electric Fields and Moving Media

Case studies for use in the teaching of basic field theory and electromechanics ideally illustrate the classic analytical solutions while both motivating discussions of engineering applications and dramatizing the physical phenomena. Experiments are particularly valuable for achieving this last purpose if they are visualized directly. To this end, a series of experiments are developed in the educational film, "Electric Fields and Moving Media," produced for the National Committee on Electrical Engineering Films by the Educational Development Center. As background for making use of that film, analytical models and connections with engineering applications are outlined.
Electrodiagnostic studies in neuromuscular disease.

ELECTRODIAGNOSTIC studies for neuromuscular disease can be a valuable asset in diagnostic and follow-up considerations.1 Their use, however, must be an extension of the clinical evaluation and not ...
The new Silk Road

Kenneth Chien and Luther Chien look to the past to inspire biomedical research of the future.
Assessment of water distribution changes in human cortical bone by nuclear magnetic resonance

A NMR spin–spin (T2) relaxation technique has been described for determining water distribution changes in human cortical bone tissue. The advantages of using NMR T2 relaxation techniques for bone water distribution are illustrated. The CPMG T2 relaxation data can be inverted to T2 relaxation distribution and this distribution then can be transformed to a pore size distribution with the longer relaxation times corresponding to larger pores. The FID T2 relaxation data can be inverted to T2 relaxation distribution and this distribution then can be transformed to bound- and mobile-water distribution with the longest relaxation time corresponding to mobile water and the middle relaxation time corresponding to bound water. The technique is applied to quantify apparent changes in porosity, bound and mobile water in cortical bone. Overall bone porosity is determined using the calibrated NMR fluid volume from the proton relaxation data divided by overall bone volume. The NMR bound and mobile water changes were determined from cortical bone specimens obtained from male and female donors of different ages. Differences in water distribution were found between specimens from male and female donors. Furthermore, the distribution of water within a single specimen was found to be non-homogeneous. Our results show that the ratio of the average bound to mobile water in bone from male donors is higher than in bone from female donors when the bone porosities are similar between male and female groups. We also show that the average bone porosity multiplied by the ratio of bound to mobile water is constant for both male and female bone groups. This parameter may be used as a measure of bone quality describing both porosity and water content, both of which may be important determinants of bone strength and fracture resistance.
About Face: Forensic Genetic Testing for Race and Visible Traits

Information from forensic genetic tests of crime scene samples has been used to make claims about suspects' race and appearance. This article discusses and critiques the techniques used to make such claims, and raises policy concerns about them.
Fiber optic polymer cure sensor

An in situ method is presented for monitoring the curing of polymeric compositions, including epoxy- and polymide-based composites. The sensor measures the difference between the refractive index of the cured and uncured composition, with the index increasing as polymerization proceeds. The method differs from all existing methods in that it relies on a self-referential differential measurement rather than on an absolute measurement, the sensor is totally independent of curing conditions and is sensitive to the extent of cure even at the latest stages. It can be used within the body of large composite structures undergoing curing in an autoclave, and it can indicate the end of cure without calibration of any kind. >
Left atrial appendage thrombus post LARIAT closure device.

1547-5271/$-see front matter B 2014 Heart Rhythm Society. All rights reserved. Embolic stroke remains one of the most severe complications of atrial fibrillation, and anticoagulation has been a problematic therapeutic option for several years. Recently, the development of alternative methods for stroke prevention, such as left atrial appendage (LAA) percutaneous closure, has been introduced, but its long-term efficacy and safety remain unknown.
Local expansion of vertex-transitive graphs and random generation in finite groups

Heuristic algorithms manipulating finite groups often work under the assumption that certain operations lead to “random” elements of the group. While polynomial time methods to construct uniform random elements of permutation groups have been known for over two decades, no such methods have previously been known for more general cases such as matrix groups over finite fields. We present a Monte Carlo algorithm which constructs an efficient nearly uniform random generator for finite groups G in a very general setting. The algorithm presumes a priori knowledge of an upper bound n on log |G|. The random generator is constructed and works in time, polynomial in this upper bound n. The process admits high degree of parallelization: after a preprocessing of length O(n logn) with O(n) processors, the construction of each random element costs O(logn) time with O(n) processors. We use the computational model of “black box groups”: group elements are encoded as (0, 1)-strings of uniform length; and an oracle performs group operations at unit cost. The group G is given by a list of generators. The random generator will produce each group element with probability (1/|G|)(1 ± ) where can be prescribed to be an arbitrary exponentially small function of n. ∗Research supported in part by NSF Grant CCR-8710078.
UV laser ionization and electron beam diagnostics for plasma lenses

A comprehensive study of focusing of relativistic electron beams with overdense and underdense plasma lenses requires careful control of plasma density and scale lengths. Plasma lens experiments are planned at the Beam Test Facility of the LBL Center for Beam Physics, using the 50 MeV electron beam delivered by the linac injector from the Advanced Light Source. We present results from an interferometric study of plasmas produced in tri-propylamine vapor with a frequency quadrupled Nd:YAG laser at 266 nm. To study temporal dynamics of plasma lenses we have developed an electron beam diagnostic using optical transition radiation to time resolve beam size and divergence. Electron beam ionization of the plasma has also been investigated.
Power-Aware Data Buffer Cache Management in Real-Time Embedded Databases

The demand for real-time data services in embedded systems is increasing. In these new computing platforms, using traditional buffer management schemes, whose goal is to minimize the number of I/O operations, is problematic since they do not consider the constraints of those platforms such as limited energy and distinctive underlying storage. In particular, due to asymmetric read/write characteristic of flash memory, minimum buffer misses neither coincide with minimum power consumption nor minimum I/O deadline miss ratio. In this paper we propose a power-aware buffer cache management scheme for real-time databases whose secondary storage is a flash memory. We focus on the problem of guaranteeing the performance goal in terms of both I/O power consumption and I/O deadline miss ratio. To address this problem, we propose logical partitioning of the global buffer pool into read and write buffer pools, and dynamic feedback control of read/write buffer pool sizes to satisfy both performance goals. We have shown through an extensive evaluation that our approach satisfies both performance goals in a variety of workloads and access patterns with considerably smaller size of buffer pools compared to baseline approaches.