cssi/SciSciGPT-SciSciNet huggingface dataset:
Strain Hardening During Mechanical Twinning and Dislocation Channeling in Irradiated 316 Stainless Steels

Localized deformation mechanisms and strain-hardening behaviors in irradiated 316 and 316LN stainless steels were investigated, and a theoretical model was proposed to explain the linear strain-hardening behavior during the localized deformation. After low temperature irradiation to significant doses the deformation microstructure changed from dislocation tangles to channels or to mechanical twins. It was also observed that irradiation hardening straightened gliding dislocations and increased the tendency for forming pileups. Regardless of these microstructural changes, the strain-hardening behavior was relatively insensitive to the irradiation. This dose-independent strain-hardening rate resulted in dose independence of the true stress parameters such as the plastic instability stress and true fracture stress. In the proposed model, the long-range back stress was formulated as a function of the number of pileup dislocations per slip band and the number of slip bands in a grain. The calculation results confirmed the experimental observation that strain-hardening rate was insensitive to the change in deformation mechanism because the long-range back stress hardening became as high as the hardening by tangled dislocations.
Effects of pill burden on discontinuation of the initial HAART regimen in minority female patients prescribed 1 pill/day versus any other pill burden.

Highly active antiretroviral therapy (HAART) is a mainstay of treatment for patients with Human Immunodeficiency Virus (HIV). Since second line HAART therapies can be costlier and less effective, it is essential to understand the duration of initial HAART therapies. The overall aim of this study was to estimate the effects of daily pill burden on the time to discontinuation of the initial HAART regimen. Patients were initially identified through the clinic's CAREWARE database. A chart review was conducted for data collection, where only adult, female, HIV-positive patients initiating therapy at the study clinic between 1 January 2001 and 31 December 2011 were included. All study subjects were followed up from the initiation of HAART to treatment discontinuation. A Kaplan–Meier curve was generated to describe time to discontinuation by regimens, and a Cox proportional hazards model was developed to assess the impact of different regimen and patient demographic characteristics on the hazard of discontinuati...
Dorsoventral Patterning in Xenopus: Inhibition of Ventral Signals by Direct Binding of Chordin to BMP-4

Chordin (Chd) is an abundant protein secreted by Spemann organizer tissue during gastrulation. Chd antagonizes signaling by mature bone morphogenetic proteins (BMPs) by blocking binding to their receptors. Recombinant Xenopus Chd binds to BMP-4 with high affinity (KD, 3 x 10(-10) M), binding specifically to BMPs but not to activin or TGF-beta1. Chd protein is able to dorsalize mesoderm and to neuralize ectoderm in Xenopus gastrula explants at 1 nM. We propose that the noncell-autonomous effects of Spemann's organizer on dorsoventral patterning are executed in part by diffusible signals that directly bind to and neutralize ventral BMPs during gastrulation.
Prevention of type 2 diabetes in young people: a theoretical perspective

Type 2 diabetes in youth is an increasing public health concern, especially in certain minority populations. The current paper consists of four sections. First, we establish the significance of the problem by presenting an overview of epidemiological and physiological evidence. Second, we discuss behavioral issues relevant to the prevention of type 2 diabetes in youth. Third, a qualitative review of existing prevention interventions specific to type 2 diabetes in youth is presented. Results suggest that modest improvements in social cognitive, dietary, and exercise outcomes are possible with diabetes intervention studies, although beneficial changes are difficult to sustain over the long term. Although theoretical frameworks are not always explicit, most studies have utilized elements of the social cognitive theory. Less attention has been paid to sociocultural and community organization variables. Finally, the paper discusses issues of risk definition and intervention sustainability, and presents a comprehensive, theoretically diverse model for the prevention of type 2 diabetes in youth. In summary, we suggest that theories of the natural history and pathophysiology of type 2 diabetes are important to identify modifiable risk factors, while theories of behavioral change are essential to modify the risk factors identified. The combination of sound physiological and behavioral theories should form the basis of prevention intervention design. In addition, an ecologic approach that takes into consideration the dynamic interactions of personal, social, and environmental factors would best promote the long-term adoption of healthful behaviors in a supportive, meaningful, and personally enjoyable context.
Statistical evaluation of the variation in laminated composite properties resulting from ply misalignment

Production tolerances must allow for deviations in ply angles in composite laminates. A Monte Carlo simulation of these deviations has been used to evaluate the distribution of properties for two symmetric laminates formed from P7SS/930 (graphite/epoxy) uniaxial composite plies. Although the nominal laminate mechanical properties are essentially identical for the two cases considered, the consistency of these properties varies with the layup. This analysis was used to select the laminate which provides the greatest consistency in Critical properties. Techniques used in this evaluation may be applied to any general laminate. This type of analysis is particularly useful in laminate evaluation whenever mechathcal properties must be tightly controlled, as typically required for optical support structures. For any given ply angle alignment tolerance and mechanical property variation, the reject rate can be estimated. Two types of ply misalignment are considered. In the first case, the alignment error of each layer is considered to be random. In the second case, systematic errors such as those which might be caused by imperfections in the cutting template that would affect all plies at a specified angle are considered. Graphs are used to present a statistical summary of the results. A program for IBM-PC1 computers using a commercially available matrix manipulation program has been developed to perform the analysis.
Appraisal of antihypertensive drug therapy.

Four completed prospective studies of drug-treated and control hypertensives utilizing double blind randomized protocols are reviewed for the purpose of evaluating the evidence on which the present therapeutic crusade is based. Patients studied were predominantly male, observed for short period, had complications or died at young age, had high incidence of previous target organ vascular disease, and did not include those whose blood pressure fell to normal with hospitalization alone. Incidence of complications associated with coronary artery disease was the same in control and treated patients. The rapidly progressive disease observed in these patients differs from that described in other natural history studies. Population screening for hypertension for the purpose of instituting drug therapy is premature because the value of antihypertensive drug treatment for the general hypertensive population has not been established.
Characterizations of microchannel plate quantum efficiency

Microchannel plates have been used over many years in astronomical applications for X-ray, UV and visible sensing. Their adaptability to various size and configuration formats have allowed a wide range of devices to be realized, employing many different forms of readout techniques and photocathode types. One problem that has arisen for a number of these programs is the issue of obtaining high quantum efficiency on a consistent basis. Several missions have suffered from problems when microchannel plates have not achieved the quantum efficiency values that are the generally accepted normal values. We have compiled an extensive set of quantum efficiency measurements which cover missions and devices produced over the past 20 years. These show that the deficiencies in MCP QE of bare MCP's also result in a corresponding decrease in QE for same MCP's coated with a photocathode. This may be interpreted as a deficiency of the MCP detection efficiency for low energy photoelectrons produced by the MCP/cathode. Recent measurements of MCP's produced by alteration of the processing procedures shows that this problem is avoidable, and gives excellent results for current generation MCP's with 5-6 micron pore sizes.
Abnormal liver function during parenteral nutrition: Relation to infusion excess

Abnormalities of liver function are frequently noted during the course of total parenteral nutrition (TPN) [6, 9, 14-171. While the functional significance of increases in “liver function tests” (LFTs) is unclear, a broad spectrum of histological changes including fatty infiltration [6, 9, 14, 15, 171, glycogen deposition [ 14, 151, and cholestasis [17] are reported to coincide with LFT abnormalities in adults. Among the proposed etiologies for such changes during TPN are excessive dextrose infusion [14, 15, 171, toxicity or imbalances of infused amino acids [6, 171, and concurrent essential fatty acid deficiency [ 111. A uniform finding among previous studies has been a temporal relationship of 1 to 3 weeks between the onset of parenteral feeding and the appearance of abnormal LFTs. This finding suggests that alterations in liver function and histology may be related to the rate of TPN infusion or to an excessive cumulative load of parenteral nutrition solutions. Parenteral Nutrition and Laboratory Methods
Entrainment in stratocumulus‐topped mixed layers

Mixed-layer theory is used to synthesize and evaluate recently proposed entrainment parametrizations (rules) for the stratocumulus-topped boundary layer. The results illustrate that recently proposed entrainment rules exhibit marked differences. Significant differences are found between rules derived from a single set of simulations and rules derived from different sets of simulations. Such differences imply steady-state boundary layers that can differ by as much as a factor of two in climatologically important properties such as vertically integrated liquid water and boundary-layer depth. In addition, surface fluxes depend significantly on entrainment, as do different measures for the limits of applicability of the mixed-layer theory. Moreover, differences among proposed entrainment rules yield steady states with different equilibrium sensitivities; models closed with some rules are more sensitive to divergence while others are more sensitive to variations in the sea surface temperature. Overall we expect that these differences should be evident in the climatology and climate sensitivity of stratocumulus derived from models which use these rules. This degree of sensitivity encourages attempts to bound entrainment rules observationally, by requiring consistency with the observed stratocumulus climatology. The analysis also encourages the use of somewhat simpler strategies for the parametrization of the stratocumulus-topped boundary layer in large-scale models. Copyright © 2002 Royal Meteorological Society.
Variable morphology of ventricular septal defect in double inlet left ventricle

The morphologic characteristics of ventricular septal defect (VSD) relative to the disposition of the atrioventricular conduction axis were studied (as far as was possible from gross observation) in 33 hearts with double inlet left ventricle. The hearts were separated into 4 groups. The hearts had either right-sided or left-sided rudimentary right ventricles (RV) coexisting with either ventriculoarterial (VA) concordance or discordance, respectively. Significant differences were noted in the morphology of the VSD according to these patterns. With right-sided rudimentary RV and VA concordance the anatomy was similar to that of classic tricuspid atresia, with an extensive outlet septum in the roof of the defect. With left-sided rudimentary RV and VA concordance, 2 further patterns were seen. In 1 pattern the arrangement was similar to that found with VA discordance. In the other, there was a pinhole VSD, a grossly hypoplastic right ventricle and a complete subaortic infundibulum in the dominant left ventricle. With VA discordance the morphology was broadly similar be the rudimentary RV right-sided or left-sided. The outlet septum was much less extensive than in the arrangement with right-sided RV and VA concordance. Minimal differences related to the formation of the right margin of the defect, which always carried the conduction axis on its left ventricular aspect. These differences dictated the "safest margins" of the defect should its excision be required during life. Basically, the left margin of the apical trabecular septum can most safely be excised.
Retrovirus-induced lymphoproliferative disease in mice undergoing graft-versus-host reaction.

The effect of graft-versus-host reaction on the course of concomminant retrovirus-induced lymphoproliferative disease was investigated. The graft-versus-host reaction was elicited by a single i.v. injection of 1.2x108 parental spleen cells into adult F1 mice. Lymphoproliferative disease was induced by a single transfusion of 0.2 ml of whole blood from donors with fully developed disease, induced by infection with retrovirus LP-BM5 MuLV. Graft-versus-host reaction and the lymphoproliferative disease each separately produced similar syndrome consisting of splenomegaly, lymphadenopathy, leukopenia, neutrophilia, reduced in vitro proliferation of spleen cells and suppression of in vivo immune responsiveness. The above symptoms were usually less pronounced during graft-versus-host reaction. Ongoing graft-versus-host reaction neither aggravated nor accelerated the course of the virus-induced lymphoproliferative disease in genetically susceptible F1 hybrids. Likewise, an ongoing graft-versus-host reaction in gen...
Pregnancy incentives, predation constraints and habitat shifts: experimental and field evidence for wild bighorn sheep

Abstract Behavioural and ecological consequences of pregnancy in a medium-sized herbivore were examined by testing the hypothesis that pregnant females should move to areas that maximize nutrient intake once the demands of gestation are high, even at the risk of increased predation. Observational and experimental data were contrasted for six populations of bighorn sheep, Ovis canadensis, living in heterogeneous environments with natural predators at Great Basin (N=4), Sonoran Desert (N=1) and northern prairie (N=1) study sites. Manipulations included the alteration of dietary protein (via alfalfa supplements) in habitats that varied in predation risk when females were at different stages of pregnancy and, hence, protein requirements. Both sexes left the mountainous terrain during late winter to feed on bajadas where emergent new grasses were highest in crude protein. In these areas females were more than twice as likely as males to flee from natural predators. Females also (1) remained closer to mountainous slopes while feeding and (2) incurred greater losses in feeding time when away from slopes than males. These data suggest that predation pressure affects the sexes differently. Results of the experimental manipulations were consistent with the posed hypothesis since protein supplements on bajadas were consumed by both sexes until emergent new grasses became more abundant on mountainous slopes. However, natural variation in female reproductive status allowed a further refinement of the extent to which pregnancy incentives and predation constraints affected habitat use. Ewes not accompanied by lambs or yearlings used areas where they were at risk from predators, such as bajadas, more frequently than those without young, observations that favour the tenet that potential predation pressure overrides increased nutrient demands during late stages of pregnancy. These data suggest that species of mammals with access to heterogeneous environments prior to parturition are ideal subjects in which to examine the extent to which habitat shifts result from balancing increased dietary requirements during late gestation and safety from potential predators.
Bimolecular Exon Ligation by the Human Spliceosome

Intron excision is an essential step in eukaryotic gene expression, but the molecular mechanisms by which the spliceosome accurately identifies splice sites in nuclear precursors to messenger RNAs (pre-mRNAs) are not well understood. A bimolecular assay for the second step of splicing has now revealed that exon ligation by the human spliceosome does not require covalent attachment of a 3' splice site to the branch site. Furthermore, accurate definition of the 3' splice site in this system is independent of either a covalently attached polypyrimidine tract or specific 3' exon sequences. Rather, in this system 3' splice site selection apparently occurs with a 5' --> 3' directionality.
Configuration factors between a small plane and a large sphere.

Diffuse configuration factors between small plane and large sphere by unit sphere method, presenting limiting cases
Studies of enzyme polymorphisms in the Kamuela population of Drosophila mercatorum. II. Evaluation of glycolytic intermediates.

A simple and effective cryogenic procedure for the extraction of glycolytic intermediates from whole Drosophila has been developed. This procedure gives consistent results when a measure (µM/liter/OD260) is adopted which corrects for differences in extraction efficiency. Using this measure and a homozygous strain of D. mercatorum, there are no significant differences among extracts for the levels of any of the 15 glycolytic intermediate or energy molecules considered. The profile of means is consistent across experimental designs and instrument types. Coefficients of variation are well below 50% for most variables. The methodology presented has the statistical power to detect a mean change of 10 to 50% using an experimental design which requires as few as 32 observations. The estimated energy charge for resting Drosophila from these studies is the expected value of 0.86.
Pathologically significant pericoronal lesions in adults: Histopathologic evaluation

Purpose: Oral and maxillofacial surgeons devote a large portion of their practice to the removal of impacted teeth. Many of these teeth have associated soft tissue that is submitted along with or without the tooth for histopathologic examination. This study reports the histopathologic diagnoses of a large series of pericoronal lesions in adults submitted to an oral and maxillofacial pathology biopsy service. Materials and Methods: Two thousand six hundred forty-six pericoronal lesions received during a 6-year period were reviewed for location, age, and histopathologic diagnosis. Results: Retrospective evaluation showed that 67.1% of all submissions were nonpathologic follicular tissue. Pathologically significant lesions were diagnosed in 32.9% of cases. Among these lesions were 673 dentigerous cysts (28.4%), 79 dentigerous cysts with mucous cell prosoplasia, 71 odontogenic keratocysts (2.68%), 19 odontomas (0.7%), 13 ameloblastomas (0.5%), 6 carcinomas (0.23%), 6 calcifying odontogenic cysts (0.23%), 4 calcifying epithelial odontogenic tumors, and 1 odontogenic myxoma (0.04%). When stratified by age, the data showed pathologically significant lesions and age are related (X2, P <.0001). Conclusions: Because of selection bias inherent in a study of this nature, population generalizations cannot be made. However, this study serves to show that the potential for the development of significant, even life-threatening, disease associated with impacted teeth is real and should be a factor in the decision-making process when oral surgeons and others are confronted with the dilemma of managing an impacted tooth. © 2002 American Association of Oral and Maxillofacial Surgeons J Oral Maxillofac Surg 60:613-617, 2002
Borrelia burgdorferi possesses a collagenolytic activity

Lyme disease is a multisystemic disorder caused by Borrelia burgdorferi, an invasive spirochete. B. burgdorferi has a predilection for collagenous tissue and one major clinical manifestation of the disease is arthritis. We have identified a collagenolytic activity in B. burgdorferi detergent lysates using iodinated gelatin as well as iodinated pepsinized human collagen types II and IV as protein substrates. In addition, we describe several proteolytic activities in B. burgdorferi with molecular masses greater than 200 kDa on sodium dodecyl sulfate polyacrylamide gels containing copolymerized gelatin. We propose that the collagenolytic activity of B. burgdorferi has a role in invasion, in the pathogenesis of Lyme arthritis, and perhaps also in other manifestations of Lyme borreliosis.
Geophysical evidence for a volcanic subsidence feature near Silver Cliff, Colorado

A prominent negative gravity and magnetic anomaly across outcrops of volcanic tuff coupled with geologic evidence for collapse and hydrothermal alteration suggest a cauldron subsidence feature on the edge of the Silver Cliff, Colorado, volcanic area.
Cellular and subcellular structure of anterior sensory pathways in Phestilla sibogae (Gastropoda, Nudibranchia).

Two sensory-cell types, subepithelial sensory cells (SSCs) and intraepithelial sensory cells (ISCs), were identified in the anterior sensory organs (ASO: pairs of rhinophores and oral tentacles, and the anterior field formed by the oral plate and cephalic shield) of the nudibranch Phestilla sibogae after filling through anterior nerves with the neuronal tracers biocytin and Lucifer Yellow. A third type of sensory cells, with subepithelial somata and tufts of stiff-cilia (TSCs, presumably rheoreceptors), was identified after uptake of the mitochondrial dye DASPEI. Each sensory-cell type has a specific spatial distribution in the ASO. The highest density of ISCs is in the oral tentacles (<1,200/mm 2 ), SSCs in the middle parts of the rhinophores (.4,000/mm 2 ), and TSCs in the tips of cephalic tentacles (100/mm 2 ). These morphologic data, together with electrophysiologic evidence for greater chemical sensitivity of the rhinophores than the oral tentacles (Murphy and Hadfield [1997] Comp. Biochem. Physiol. 118A:727‐735; Boudko et al. [1997] Soc. Neurosci. Abstr. 23:1787), led us to conclude that the two pairs of chemosensory tentacles serve different chemosensory functions in P. sibogae; i.e., ISCs and the oral tentacles serve contact- or short-distance chemoreception, and SSCs and the rhinophores function for long-distance chemoreception or olfaction. If this is true, then the ISC subsystem probably represents an earlier stage in the evolution and adaptations of gastropod chemosensory biology, whereas among the opisthobranchs, the SSC subsystem evolved with the rhinophores from ancestral cephalaspidean opisthobranchs. J. Comp. Neurol. 403:39‐52, 1999. r 1999 Wiley-Liss, Inc.
Analysis of diffractive optical elements using a nonuniform finite-difference time-domain method

We present the analysis of diffractive optical elements (DOEs) using a two-dimensional nonuniform finite-difference time- domain (FDTD) method. Because the feature sizes in a DOE profile are in general irregular, their analysis using a conventional formulation of the FDTD, i.e., a uniform orthogonal grid, typically requires a high spatial sampling. This in turn raises the computational time and memory requirements for analysis. However, by using a nonuniform grid configuration one can more accurately represent the computation boundary of the DOE, and consequently reduce computational costs. To this end we apply our method to the analysis of both multilevel and subwavelength DOEs to illustrate its utility.
Chaotic dynamics of coherent structures

Abstract A variety of chaotic flows evolving in relatively high-dimensional spaces are considered. It is shown through the use of an optimal choice of basis functions, which are consequence of the Karhunen-Loeve procedure, that an accurate description can be given in a relatively low-dimensional space. Particular examples of this procedure, which are presented, are the Ginzburg-Landau equation, turbulent convection in an unbounded domain and turbulent convection in a bounded domain.
Prenatal diagnosis of Canavan disease.

Spongy degeneration of the brain, Canavan disease (CD; McKusick 271900), is an autosomal recessive disorder prevalent among Ashkenazi Jews. The disease is a leukodystrophy manifested by macrocephaly, mental retardation and early death (Canavan 1931; van Bogaert and Bertrand 1967). Patients with Canavan disease excrete large amounts of β-acetylaspartic acid (NAA) in their urine and have a profound deficiency of aspartoacylase (EC 3.5.1.15) in their cultured skin fibroblasts and other tissues (Matalon et al 1988, 1989)
Preferential sputtering in the 3d transition metal monoxides

Sputtering with 2 keV Ar + has been found to result in preferential oxygen removal for NiO(100) and CoO(100) single crystals but not for the thermodynamically more stable MnO(100) sample. Substrate temperatures that are only slightly elevated from room temperature (≳350 K) are required to effect sample reduction, a fact which may explain conflicting reports of congruent and preferential sputtering for NiO and CoO in the literature. The substrate temperature affects both the steady state surface composition of the oxide and the ion fluence to reach steady state. The kinetics of sample reduction is analyzed for NiO and can be described as a balance between the sputter rate and the rate of oxygen diffusion from subsurface layers. During Ar + reduction of the NiO(100) surface, zero valent nickel builds up at the crystal surface and coalesces into ordered nickel islands for surface concentrations reduced to approximately 25% of the stoichiometric value and below. Two additional oxygen species are also observed for extensively bombarded NiO samples.
Gene expression profiling during erythroid differentiation of K562 cells.

Abstract ABSTRACT We studied the temporal changes in gene expression in K562 cells at intervals from 2 to 48 h following induction using differential display polymerase chain reaction and gene expression arrays. More than 110 cDNA fragments representing 86 unique mRNAs were either up- or downregulated during erythroid differentiation. Sixty-one of the differentially expressed cDNA fragments had more than 95% homology to known GenBank sequences; 21 represented cDNA sequences with only dbEST or high-throughput gene-screening database matches. Four fragments had no database matches. Using gene expression arrays, 73 differentially expressed genes were observed. Unique expressed sequence tags (ESTs) were used to “clone” two novel genes from available databases and their tissue expression was examined. Erythroid maturation in induced K562 cells is associated with differential expression of many genes. Some differentially expressed clones were transcription factors and 25 expressed fragments with open reading frames were found whose function remains unknown.
Adrenergic innervation of the rat submandibular and parotid glands. An electron microscopic autoradiographic study of the uptake of tritiated norepinephrine.

The adrenergic innervation of the rat submandibular and parotid glands was investigated by monitoring the uptake of H3-NE by nerve terminals with electron microscopic autoradiographic techniques. Both glands contained nerve bundles in the stroma encompassed by a Schwann cell sheath. Silver grains due to H3-NE were observed overlying several nerve terminals found in these nerve bundles, while other nerve terminals in the same bundle were devoid of silver grains. In the submandibular gland, adrenergic nerve terminals characterized by silver grains due to H3-NE were observed in the stroma in close relationship to, but not in direct apposition to parenchymal cells. In the parotid gland, silver grains due to H3-NE were observed overlying nerve terminals contained within the basement lamina and in close contact with acinar cells.
Overexpression of miR-7-1 Increases Efficacy of Green Tea Polyphenols for Induction of Apoptosis in Human Malignant Neuroblastoma SH-SY5Y and SK-N-DZ Cells

Neuroblastoma is an extracranial solid tumor that usually occurs in infants and children. Malignant neuroblastomas remain mostly refractory to currently available chemotherapeutic agents. So, new therapeutic agents and their molecular mechanisms for induction of cell death must be explored for successful treatment of human malignant neuroblastomas. Two polyphenolic compounds, which are abundant in green tea, are (-)-epigallocatechin (EGC) and (-)-epigallocatechin-3-gallate (EGCG) that possess impressive anti-cancer properties. It is not known yet whether EGC and EGCG can modulate the levels of expression of specific microRNAs (miRs) for induction of apoptosis in human malignant neuroblastomas. In this investigation, we revealed that treatment with EGC or EGCG caused induction of apoptosis with significant changes in expression of specific oncogenic miRs (OGmiRs) and tumor suppressor miRs (TSmiRs) in human malignant neuroblastoma SH-SY5Y and SK-N-DZ cell lines. Treatment of both cell lines with either 50 μM EGC or 50 μM EGCG decreased expression of the OGmiRs (miR-92, miR-93, and miR-106b) and increased expression of the TSmiRs (miR-7-1, miR-34a, and miR-99a) leading to induction of extrinsic and intrinsic pathways of apoptosis. Our data also demonstrated that overexpression of miR-93 decreased efficacy while overexpression of miR-7-1 increased efficacy of the green tea polyphenols for induction of apoptosis in both cell lines. In conclusion, our current investigation clearly indicates that overexpression of miR-7-1 can highly potentiate efficacy of EGCG for induction of apoptosis in human malignant neuroblastoma cells.
The Effect of Specific Sterols on Cell Size and Fatty Acid Composition of Tetrahymena pyriformis W

The size and fatty acid composition of Tetrahymena pyriformis W cells were influenced by the provision of a nutritional supplement of ergosterol, cholesterol, or tetrahymanol, but not of 20-isocholesterol. Ergosterol and cholesterol addition led to a reduction in cellular volume, an increase in glycerophospholipid saturated fatty acid content, and an increase in palmitoleic acid and its metabolic products when compared to unsupplemented controls. Tetrahymanol supplementation resulted in an increase in cellular volume, a decrease in saturated fatty acid content, and a reduction in palmitoleic acid and derivatives. 20-Isocholesterol was accumulated by the cells; however, this compound had no effect on any of the parameters followed in this investigation and had only a small depressant effect on tetrahymanol biosynthesis. Ergosterol and cholesterol had the same impact on the ciliates, even though the ergosterol-supplemented cells contained approximately three times as much free sterol as did cholesterol-grown cells. The amount of the free cholesterol and metabolic products in supplemented cultures was similar to the amount of tetrahymanol present in control cultures. This observation suggests that the cells recognize qualitative differences among the various polycyclic alcohols rather than responding to the amount of sterol present. Increased cellular levels of tetrahymanol led to a response unlike that of the true sterols, which again suggests that the high degree of specificity depends on the structure of the added polycyclic alcohol. The changes in fatty acid composition may be required to maintain proper interaction of the polar lipids and the polycyclic alcohols to give an appropriate degree of membrane fluidity.
Prescription opioid misuse among youth in primary care: A comparison of risk factors

being significant (p=0.015). Patients reporting substance use were also less likely to be consistent condom users. Conclusions: This study suggests that adolescents self-referring to an adolescent health clinic are likely to engage in multiple risk behaviors and involvement in sexual risky behavior is related to substance use. Therefore, there is a significant need for medical providers to screen adolescents for both sexual risk behaviors and substance use, which provides an opportunity for comprehensive care. Financial support: NIDA R34DA031806.
Measuring and predicting the amplitude and phase for three-wave interactions

Using Fresnel phase retrieval method for two intensity profiles, we first construct the phase-map of the HeNe laser beam in a specially built optical system. After validating this result with the analytical value we proceeded to the nonlinear three-wave interaction. The Fresnel technique is once again employed to obtain the phase map of the input pump and signal beam. The phase information of these input beams are then used in a two-dimensional numerical model we have developed for three-wave nonlinear interactions. The outcome from the numerical model is then compared to the phase map of the output pump and signal beam.
Thermal conductivity of three noble gases with carbon monoxide

Abstract The paper reports the results of new measurements of the thermal conductivity of binary mixtures of helium, neon and argon with carbon monoxide at 27.5°C and in the pressure range 0.7–12 MPa. The viscosity of these mixtures had been measured previously. The availability of their interaction viscosity allows us to calculate the contribution of the internal degrees of freedom. The Monchick-Pereira-Mason equation provides a reasonable, but far from perfect, basis for a correlation. Even though the low-density viscosity of the present mixtures was essentially the same as the corresponding mixtures with nitrogen, the thermal conductivity is different, pointing to a significant contribution from the rotational degrees of freedom. A comparison between a calculation of the density effect based on a modification of the Thorne-Enskog theory due to Mason et al. shows the same reasonable agreement (of order 2%) as that ascertained in earlier measurements on other mixtures.
Normal Remodeling of the Oxygen-Injured Lung Requires the Cyclin-Dependent Kinase Inhibitor p21Cip1/WAF1/Sdi1

Alveolar cells of the lung are injured and killed when exposed to elevated levels of inspired oxygen. Damaged tissue architecture and pulmonary function is restored during recovery in room air as endothelial and type II epithelial cells proliferate. Although excessive fibroblast proliferation and inflammation occur when abnormal remodeling occurs, genes that regulate repair remain unknown. Our recent observation that hyperoxia inhibits proliferation through induction of the cyclin-dependent kinase inhibitor p21Cip1/WAF1/Sdi1, which also facilitates DNA repair, suggested that p21 may participate in remodeling. This hypothesis was tested in p21-wild-type and -deficient mice exposed to 100% FiO2 and recovered in room air. p21 increased during hyperoxia, remained elevated after 1 day of recovery before returning to unexposed levels. Increased proliferation occurred when p21 expression decreased. In contrast, higher and sustained levels of proliferation, resulting in myofibroblast hyperplasia and monocytic inflammation, occurred in recovered p21-deficient lungs. Cells with DNA strand breaks and expressing p53 were observed in hyperplastic regions suggesting that DNA integrity had not been restored. Normal recovery of endothelial and type II epithelial cells, as assessed by expression of cell-type-specific genes was also delayed in p21-deficient lungs. These results reveal that p21 is required for remodeling the oxygen-injured lung and suggest that failure to limit replication of damaged DNA may lead to cell death, inflammation, and abnormal remodeling. This observation has important implications for therapeutic strategies designed to attenuate long-term chronic lung disease after oxidant injury.
The Southern Oscillation Revisited: Sea Level Pressures, Surface Temperatures, and Precipitation

An update is given of the global correlation and regression patterns of sea level pressure associated with the Southern Oscillation, based upon the reanalyses from the National Centers for Environmental Prediction‐National Center for Atmospheric Research for 1958‐98, a period independent of that of early work. Features over the oceans are better defined than was previously possible and most features prove to be robust, although climate changes such as the 1976 climate shift have evidently altered some important relationships, such as those with Southeast Asia. Associated surface temperature patterns are also shown over the same interval and reveal striking
Development of a quality assurance program as an integral part of the physical therapy system

The purposes of this article are to describe the conditions that must be met and the process that must be carried out to develop, implement, and evaluate a quality assurance program. The conditions to be met are administrative support for the program; knowledge of quality assurance theories and components (including structure, process, and outcome standards); and a commitment of the department members to quality assurance. The participative approach to program development is essential to the acceptance and implementation of the program. The process is cyclical in nature with the actual program design based on the needs of the people to be served. The department's policies and procedures manual provides the appropriate place for the documentation of the program standards so they are easily accessible to all staff and are an integral part of the delivery system. External peer review is used in measuring the potential for success of the program's structure.
The effect of intranasal fluticasone propionate irrigations on salivary cortisol, intraocular pressure, and posterior subcapsular cataracts in postsurgical chronic rhinosinusitis patients

Background Intranasal corticosteroid irrigations, especially budesonide, are used increasingly in the management of chronic rhinosinusitis. In post–endoscopic sinus surgery patients, irrigations may offer improved delivery at higher doses to the paranasal sinuses than intranasal spray preparations. Fluticasone propionate may have higher potency and lower systemic bioavailability than budesonide, but there is little data on its effects as an intranasal irrigation on the hypothalamic-pituitary-adrenal axis or on ocular findings. Methods Adult patients who had previously undergone bilateral endoscopic sinus surgery and had not taken systemic corticosteroids in the last 6 months were prospectively enrolled. Subjects irrigated with 3 mg of fluticasone propionate in 240 mL saline solution twice daily. Salivary cortisol, intraocular pressure, and the presence of posterior subcapsular cataracts were measured before drug administration and after 6 weeks of continuous use. Results Twenty-three subjects completed the study. No subjects had salivary cortisol levels below the normal range before or after therapy, and there was no statistical difference in mean salivary cortisol levels pretreatment and posttreatment (0.294 vs 0.392 μg/dL; p = 0.27). There was no clinical or statistical difference in mean intraocular pressure before or after therapy (13.3 vs 13.3 mmHg; p = 0.86). No subjects developed a posterior subcapsular cataract. Conclusion Fluticasone propionate irrigations did not suppress salivary cortisol levels or result in ocular changes. Irrigation with fluticasone propionate 3 mg in 240 mL saline twice daily may be a safe alternative to other intranasal or systemic corticosteroid treatments for chronic rhinosinusitis patients.
Circulating autoantibodies to oxidized LDL correlate with impaired coronary endothelial function after cardiac transplantation

Objective— The oxidative modification of low density lipoprotein (LDL) may play a role in the pathogenesis of transplant-associated arteriosclerosis. Oxidized LDL (OxLDL) is immunogenic as well as atherogenic, and the level of autoantibodies to OxLDL has been taken as an index of the oxidant state of LDL. Because endothelial dysfunction is key in the initiation of transplant-associated arteriosclerosis, we postulated that the level of OxLDL autoantibody is associated with the degree of impairment of coronary endothelial function. Methods and Results— Coronary endothelium-dependent dilation was assessed by using intracoronary acetylcholine and endothelium-independent dilation by nitroglycerin in 36 cardiac transplant recipients within 1 year of transplantation. The coronary responses to acetylcholine ranged from −37% (vasoconstriction) to 31% (vasodilation), and the responses to nitroglycerin ranged from 0% to 42% (vasodilation). The coronary vasomotor response to acetylcholine was significantly and invers...
Fluid flow and reactive transport around potential nuclear waste emplacement tunnels at Yucca Mountain, Nevada

The evolution of fluid chemistry and mineral alteration around a potential waste emplacement tunnel (drift) is evaluated using numerical modeling. The model considers the flow of water, gas, and heat, plus reactions between minerals, CO2 gas, and aqueous species, and porosity permeability-capillary pressure coupling for a dual permeability (fractures and matrix) medium. Two possible operating temperature modes are investigated: a high-temperature case with temperatures exceeding the boiling point of water for several hundred years, and a low-temperature case with temperatures remaining below boiling for the entire life of the repository. In both cases, possible seepage waters are characterized by dilute to moderate salinities and mildly alkaline pH values. These trends in fluid composition and mineral alteration are controlled by various coupled mechanisms. For example, upon heating and boiling, CO2 exsol ution from pore waters raises pH and causes calcite precipitation. In condensation zones, this CO2 redissolves, resulting in a decrease in pH that causes calcite dissolution and enhances feldspar alteration to clays. Heat also enhances dissolution of wallrock minerals leading to elevated silica concentrations. Amorphous silica precipitates through evaporative concentration caused by boiling in the high-temperature case, but does not precipitate in the low-temperature case. Some alteration of feldspars to clays and zeolites is predicted in the high-temperature case. In both cases, calcite precipitates when percolating waters are heated near the drift. The predicted porosity decrease around drifts in the high-temperature case (several percent of the fracture volume) is larger by at least one order of magnitude than in the low temperature case. Although there are important differences between the two investigated temperature modes in the predicted evolution of fluid compositions and mineral alteration around drifts, these differences are small relative to the model uncertainty and the variability of water compositions at Yucca Mountain.
Lazy maintenance of materialized views

Materialized views can speed up query processing greatly but they have to be kept up to date to be useful. Today, database systems typically maintain views eagerly in the same transaction as the base table updates. This has the effect that updates pay for view maintenance while beneficiaries (queries) get a free ride! View maintenance overhead can be significant and it seems unfair to have updates bear the cost. We present a novel way to lazily maintain materialized views that relieves updates of this overhead. Maintenance of a view is postponed until the system has free cycles or the view is referenced by a query. View maintenance is fully or partly hidden from queries depending on the system load. Ideally, views are maintained entirely on system time at no cost to updates and queries. The efficiency of lazy maintenance is improved by combining updates from several transactions into a single maintenance operation, by condensing multiple updates of the same row into a single update, and by exploiting row versioning. Experiments using a prototype implementation in Microsoft SQL Server show much faster response times for updates and also significant reduction in maintenance cost when combining updates.
Fast algorithms for 2-D least squares FIR filtering

A general set up for the development of fast algorithms for batch and adaptive least squares (LS) 2-D finite impulse response (FIR) filtering is presented. The proposed algorithms accommodate filter mask with arbitrary boundaries shape, and utilize scalar operations, only. >
Increased Reliability with SSPiRAL Data Layouts

We evaluate the reliability of storage system schemes consisting of an equal numbers of data disks and parity disks where each parity disk contains the exclusive or (XOR) of two or three of the data disks. These schemes are instances of Survivable Storage using Parity in Redundant Array Layouts (SSPiRAL). They have the same storage costs as mirrored organizations and use very simple parity schemes. Through a novel dynamic analysis of the likelihood of data losses, we show that these schemes are one hundred thousand to a million times less likely to lose data than a comparable mirrored organization. We also found that schemes where each parity disk contains the exclusive or of three data disks performed much better than schemes where each parity disk contains the exclusive or of only two data disks.
Medical education in the 21st century.

This commentary is a reaction of medical educators and health practitioners to the Josiah Macy Jr. Foundation's recently released report, Revisiting the Medical School Mis- sion at a Time of Expansion. The report is a fresh assessment of what more medical schools must do to prepare students for 21st century challenges and opportunities to improve the health status of the population including underserved groups.
Enhancing the clinical pathway for patients undergoing axillary lymph node dissection

Abstract Background Day-case axillary lymph node dissection (ALND) is not standard practice. Here we assess the feasibility of converting this traditional inpatient procedure to an outpatient procedure without compromising the quality or continuity of patient care, identify barriers to introducing an enhanced clinical pathway based on this conversion, and report strategies employed to overcome these barriers. Methods Consecutive patients ( n = 282) undergoing ALND alone or with a concurrent breast procedure (excluding mastectomy/reconstruction) over a 12-month period were recorded in a prospective database. Assessed outcomes were successful discharge the day of surgery, early postoperative complication rates, and readmission rates. Results From July 2009 to June 2010, 282 ALNDs were performed at Memorial Sloan-Kettering Cancer Center. 240 (85.1%) were performed as an outpatient procedure and 42 (14.9%) had inpatient ALND. The readmission rate was 0.8% (2/240), and the reoperation rate was 0.7% (2/282). Outpatient ALND procedure implementation created 240 additional beds over the 12-month study period. Identified barriers to implementing this new clinical pathway included patient expectations, reducing narcotic administration while optimizing postoperative pain control, and facilitating preoperative patient education. Conclusion ALND may be safely performed as a day-case procedure. The key to successfully implementing ALND as a day-case procedure is a multidisciplinary team approach combined with enhanced pre and postoperative patient education. In addition, changes in the mindsets of patients and health care providers are essential.
An efficient Bayes solution to AR signal modelling for short sequences

A Bayesian approach to autoregressive (AR) signal modelling is proposed. In contrast to previous research, the exact posterior density of the model parameters is utilized and minimum mean square estimates (MMSE) are evaluated. To compute the estimates, a numerically efficient procedure is presented which can be viewed as an alternative to multidimensional optimization. Our approach can be used to investigate many signal characteristics such as the signal's spectrum, marginal densities for prediction or even model selection. Simulation results confirm our expectations and illustrate the improvement over the classic, maximum conditional likelihood (MCL) approach to AR signal modelling. >