cssi/SciSciGPT-SciSciNet huggingface dataset:
Perianal manifestations of human immunodeficiency virus infection: experience with 260 patients.

PURPOSE: Individuals infected with the human immunodeficiency virus often have disorders affecting the anorectum. These disorders may be complex and difficult to treat. We reported our early experience with 40 human immunodeficiency virus-positive patients with perianal disorders in 1990. We now present our series of 260 consecutive human immunodeficiency virus-positive patients with perianal disorders who underwent evaluation between 1989 and 1996 to examine the distribution of disorders, their treatments, and outcomes. METHOD: Patients were identified at initial presentation and followed prospectively. RESULTS: Two-hundred forty-nine (96 percent) of 260 patients were male, with an average age of 34.9 (range, 19–58) years. Average duration of human immunodeficiency virus positivity was 5 years, 5 months, with a maximum of 11 years, 5 months. Median CD4 count was 175 (range, 2–1,100) cells/mm3. Only 89 (34 percent) patients satisfied the criteria of the Centers for Disease Control and Prevention's for acquired immunodeficiency syndrome at presentation. The most frequent major presenting symptoms were anorectal pain (55 percent), a mass (19 percent), and blood in the stool (16 percent). Risk factors included homosexuality (75 percent) and a prior history of sexually transmitted disease (45 percent). Forty different perianal disorders were identified, which were categorized as benign noninfectious (18), infectious (14), neoplastic (6), and septic (2). The most common disorders were condyloma (42 percent), fistula (34 percent), fissure (32 percent), and abscess (25 percent). Neoplasms were present in 19 patients (7 percent). One hundred seventy-one patients (66 percent) had more than one disorder, with an average of 2.9 disorders among these patients. Four hundred eighty-five procedures were performed on 178 patients (2.7/patient), with no mortalities and a 2 percent complication rate. Thirty-one patients (12 percent) died during the course of follow-up, but anorectal disease was the cause of death in only two patients. CONCLUSIONS: Perianal manifestations of human immunodeficiency virus infection are common, often multiple, and varied. Patients with perianal disorders seek treatment throughout the course of the human immunodeficiency virus infection, and a perianal condition may be this disease's initial manifestation. Although recurrence is common and healing delayed, improved overall management of human immunodeficiency virus infection and a healthier human immunodeficiency virus-positive patient population have improved the outcome of surgical intervention in human immunodeficiency virus-infected patients with perianal disorders.
Rapid antigen testing for group A Streptococcus by DNA probe

The Gen-probe group A Streptococcus direct test (GASD), a nucleic acid probe assay for detecting GAS from throat swabs, has recently been developed. The test uses an acridium ester-labeled DNA probe which is complementary to the rRNA of Streptococcus pyogenes. In this study, 318 single culturette throat swabs were tested by this method using culture as a "gold standard." After plating onto trypticase soy agar plates with 5% sheep blood, swabs were stored at 4 degrees C for no more than 72 h before the probe assay was performed. Our patient population consisted of symptomatic outpatients seen in the Memorial Hospital Emergency Department and in the Family Care Center. After discrepancy testing, sensitivity, specificity, and positive and negative predictive values were 91.4%, 97%, 91.4%, and 97%. The GASD is a rapid, easy-to-perform method for batch screening for streptococcal pharyngitis.
Solutionizing effects on deformation-induced phase transformations in 2014 aluminum composite

A solutionizing heat treatment of 2014 aluminum alloy reinforced with 0.15 volume fraction of alumina particles (VFAP) results in deformation-induced precipitation during rolling and tensile deformation, with 0.10 VFAP, at room temperature. The extent of precipitation increases with increase in time and/or temperature of solutionizing. An attempt has been made to identify the various types of precipitates in the samples deformed to a given strain and in fractured conditions. The work-hardening curves and tensile properties of the composites have been shown to be dependent on the time and temperature combination of the solutionizing process.
Fabrication of Magnetic Thin Films by a Layer-by-Layer Self-Assembly Approach

The novel copolymer poly(5-methacryloylamido-1,10-phenanthroline-co-methacrylic acid) (PMPMA) containing a phenanthroline ring was prepared by free radical polymerization. The synthesized monomer and copolymer have been confirmed by FT-IR, 1H NMR spectra, and element analysis. A series of multilayer films, which were fabricated via layer-by-layer self-assembly with the polymer PMPMA and the transition metal neutralized poly(styrene 4-sulfonate) (PSSNi or PSSCu) on thin plastic substrate polyethylene film (PE), were described. The coordination interaction between the two nitrogen atoms of the PMPMA and the transition metal ions of the PSSM was the driving force for building up the multilayer film, which was identified by infrared spectroscopy. UV−vis spectra and AFM images were applied to monitor these films, and the results indicate that the assembling process is relatively uniform. The magnetic behavior was examined as a function of magnetic field strength at 5 K and as a function of temperature (5−300 K...
A barrier falls

Electronic devices based on carbon nanotubes have a bright future — even more so now that a way has been found to eliminate the 'Schottky barrier' that hinders the injection of electrons into them.
On large axisymmetrical deflection states of spherical shells

A boundary layer analysis is carried out to determine the possible form of large axisymmetrical deflection states for thin elastic spherical shells subjected to uniform external pressure. For the case of complete spheres it is shown that the governing equations admit boundary layer solutions corresponding to large deflections provided the pressure is sufficiently small. However, such solutions are found to exist for nonshallow clamped spherical caps for a much wider range of pressure. Numerical results are presented for the latter case.
Institutional Capacity Building and Legal Reform in Iraq: Toward Innovation and Public Administration Modernization

Iraq is often cited as a test case as to whether “nation-building” can work. Since 2003, the U.S. government has been advancing institutional capacity development with Iraq’s national government. Now 10 years later, it is clear that the program, the largest such as U.S. government program since the Vietnam War, has been a success. Tangible durable institutional reforms are now in place to professionalize the civil service, improve electricity production, make public procurement more transparent and efficient, and upgrade budget formulation and execution. The program, known locally as USAID/Tatweer, worked across executive branch agencies, to improve government performance and expand institutional capacity development. Its accomplishments, so far almost entirely unrecognized by the media, will continue to advance democratic change in Iraq for generations to come.
Spontaneous and synaptic input from granule cells and the perforant path to dentate basket cells in the rat hippocampus.

To characterize excitatory inputs to dentate basket cells from dentate granule cells and the perforant path, the whole-cell recording technique was used in neonatal rat hippocampal slices. Spontaneous excitatory input to basket cells was also examined and compared to that of other interneurons in the dentate gyrus. Basket cells were separable from other neurons in the dentate gyrus based on morphology and location, as determined by biocytin staining following recording, and by resting membrane potential, propensity to fire action potentials spontaneously, and miniature excitatory postsynaptic current (EPSC) characteristics. Minimal electrical stimulation of the granule cell layer evoked in basket cells short latency EPSCs that were composed of both N-methyl-D-aspartate (NMDA) and α-amino-3-hydroxy-5-methyl-4-isoxazole-propionate (AMPA) components as judged by their time course, voltage dependence, and blockade by selective antagonists. Perforant path EPSCs exhibited slower kinetics than EPSCs evoked by granule cell stimulation. Like granule cell evoked EPSCs, however, perforant path EPSCs were composed of both NMDA and AMPA components. Minimal electrical stimulation of the granule cell layer and perforant path evoked monosynaptic EPSCs in only 67% and 62% of the trials, respectively, suggesting that these inputs are as unreliable as previously determined inputs from CA3 pyramidal cells (48%). Tetrodotoxin-insensitive spontaneous miniature EPSCs were frequent in basket cells and non-basket interneurons residing either at the border between the granule cell layer and the hilus or deep within the hilus. Miniature EPSCs recorded from all cells held at −70 mV were blocked completely by 3 μSM 6-cyano-7-nitro-quinoxaline-2,3-dione (CNQX). Though a component of the miniature EPSCs recorded from border and deep hilar interneurons at +40 mV was blocked by the NMDA receptor antagonist D-2-amino-phosphonovaleric acid (D-APV), miniature EPSCs in basket cells were insensitive to D-APV. We conclude that input from granule cells and the perforant path results in activation of basket cells via glutamatergic synapses that employ both NMDA and AMPA receptors. These inputs to basket cells likely contribute to feedback and feedforward inhibition of granule cells. The absence of an NMDA receptor component in spontaneous miniature EPSCs of dentate basket cells implies a difference in organization of excitatory synapses made onto basket cells compared with other hilar interneurons. © 1995 Wiley-Liss, Inc.
An efficient dynamic scheduling scheme for H.264/AVC encoding on multi-core architecture

The popular wave front parallelization has been proposed to encode H.264/AVC video employing macro-block level parallelism. This approach, however, fails to achieve an optimum performance due to a significant overhead of barrier-based synchronization. All threads must wait for the slowest ones to complete encoding before starting a next processing wave. In this paper, we propose a dynamic scheduling for parallel encoding without employing the barrier synchronization. In this approach, current threads will 1) keep recursively encoding any new ready macro-blocks, and; 2) load-balance any other ready ones to a global shared queue, which is accessed by all threads. We further propose an adaptive dynamic scheduling to mitigate the access contention at the global queue, and considers cache locality with due to the underlying hierarchical core/cache topology. The adaptive dynamic scheduling employs multiple distributed queues, and schedule tasks. To achieve both locality and load balance, neighboring macro-blocks are preferably scheduled to nearby cores. We design, implement, and evaluate our scheme on a 32-core SGI server. Running real benchmarks, we observe that our scheme outperforms wave front parallelization by 200%, and achieves 65% to 70% of the maximum encoding speedup.
GCP II inhibition rescues neurons from gp120IIIB-induced neurotoxicity

Excessive glutamate neurotransmission has been implicated in neuronal injury in many disorders of the central nervous system (CNS), including human immunodeficiency virus (HIV)-associated dementia. Gp120IIIB is a strain of a HIV glycoprotein with specificity for the CXCR4 receptor that induces neuronal apoptosis in in vitro models of acquired immunodeficiency syndrome (AIDS)-induced neurodegeneration. Since the catabolism of the neuropeptide N-acetylaspartylglutamate (NAAG) by glutamate carboxypeptidase (GCP) II increases cellular glutamate, an event associated with excitotoxicity, we hypothesized that inhibition of GCP II may prevent gp120IIIB-induced cell death. Furthermore, through GCP II inhibition, increased NAAG may be neuroprotective via its agonist effects at the mGlu3 receptor. To ascertain the therapeutic potential of GCP II inhibitors, embryonic day 17 hippocampal cultures were exposed to gp120IIIB in the presence of a potent and highly selective GCP II inhibitor, 2-(phosphonomethyl)-pentanedioic acid (2-PMPA). 2-PMPA was found to abrogate gp120IIIB-induced toxicity in a dose-dependent manner. Additionally, 2-PMPA was neuroprotective when applied up to 2 h after the application of gp120IIIB. The abrogation of apoptosis by 2-PMPA was reversed with administration of mGlu3 receptor antagonists and with antibodies to transforming growth factor (TGF)-β. Further, consistent with the localization of GCP II, 2-PMPA failed to provide neuroprotection in the absence of glia. GCP II activity and its inhibition by 2-PMPA were confirmed in the hippocampal cultures using radiolabeled NAAG and high-performance liquid chromatography (HPLC) analysis. Taken together, these data suggest that GCP II is involved in mediating gp120-induced apoptosis in hippocampal neurons and GCP II inhibitors may have potential in the treatment of neuronal injury related to AIDS.
Direct contact drying of a moving porous strip

ABSTRACT Combined heat transfer and evaporation dynamics are analyzed during drying of a continuously moving, porous strip which is in direct contact with a heated plate. A transient, quasi-two-dimensional model of conjugate heat transfer between a hot massive externally /internally heated plate and wet porous strip moving along the plate is developed by accounting for evaporation dynamics. The model consists of four conjugate energy conservation equations with proper boundary/interface conditions which describe the heat transfer in four distinct zones (1-electrically or indirectly heated massive metal plate, 2-thin superheated vapor film resulting from vaporization of water in the porous strip that separates hot plate and porous strip, 3-dry region of the porous strip, and 4-wet region of the porous strip). The relevant dimensiouless parameters governing the problem are identified, and results of parametric calculations are reported to gain fundamental understanding of the process.
Domain organization of Salmonella typhimurium formylglycinamide ribonucleotide amidotransferase revealed by X-ray crystallography.

Formylglycinamide ribonucleotide amidotransferase (FGAR-AT) catalyzes the ATP-dependent conversion of formylglycinamide ribonucleotide (FGAR) and glutamine to formylglycinamidine ribonucleotide (FGAM), ADP, Pi, and glutamate in the fourth step of the purine biosynthetic pathway. In eukaryotes and Gram-negative bacteria, FGAR-AT is encoded by the purL gene as a multidomain protein with a molecular mass of about 140 kDa. In Gram-positive bacteria and archaebacteria FGAR-AT is a complex of three proteins: PurS, PurL, and PurQ. We have determined the structure of FGAR-AT (PurL) from Salmonella typhimurium at 1.9 A resolution using X-ray crystallography. PurL is the last remaining enzyme in the purine biosynthetic pathway to have its structure determined. The structure reveals four domains: an N-terminal domain structurally homologous to a PurS dimer, a linker region, an FGAM synthetase domain homologous to an aminoimidazole ribonucleotide synthetase (PurM) dimer, and a triad glutaminase domain. The domains ...
Almost Commuting Unitaries and Classification of Purely Infinite SimpleC*-Algebras☆

We show that, for any irrational rotational algebraAθ,Aθ⊗O2≅O2. This is proved by combining recently established results forC*-algebras of real rank zero with the following result: For anye>0, there isδ>0, such that for any pair of unitariesu,vin any purely infinite simpleC*-algebraAwithK1(A)=0 satisfies‖uv−vu‖<δandκ(u, v)=0.There is a pair of commuting unitariesU,V∈Awith finite spectrum such that‖u−U‖<eand‖v−V‖<e.More general results concerning almost commuting unitaries are also obtained.
A metal ion-based method for the screening of nitrilases

In this paper we describe a colorimetric method for the screening of nitrilases. When a buffered solution of CoCl2 is added to a nitrilase-catalyzed hydrolysis reaction, the ammonia product forms a complex with the cobalt ion resulting in a color change from light pink to yellow, which can readily be quantified using a spectrophotometer at 375 nm. This method has been demonstrated for both wild-type and evolved nitrilases.
Antioxidant-induced Phosphorylation of Tyrosine 486 Leads to Rapid Nuclear Export of Bach1 That Allows Nrf2 to Bind to the Antioxidant Response Element and Activate Defensive Gene Expression

Antioxidants cause stabilization and nuclear translocation of NF-E2-related factor 2 (Nrf2), where it binds to the antioxidant response element (ARE) and induces up-regulation of defensive genes that protect cells against oxidative and electrophilic stress. Bach1, the negative regulator of Nrf2, competes with Nrf2 for binding to the ARE in the human NQO1 promoter. In this study, we demonstrate that Bach1 exits the nucleus within 1–2 h upon antioxidant treatment. Genistein, an inhibitor of tyrosine kinases, blocked nuclear export of Bach1. Site-directed mutagenesis and immunoprecipitation assays identified tyrosine 486 that was phosphorylated in response to the antioxidant and was essential for nuclear export of Bach1. Chromatin immunoprecipitation assays revealed a competitive interplay between Bach1 and Nrf2 at 1–2 and 4 h for binding to the human NQO1 ARE. Luciferase and real time PCR assays showed a significant decrease in antioxidant induction of reporter activity and mRNA levels in cells transfected with mutant Bach1 compared with wild type. This decrease was due to the absence of nuclear export of the mutant protein. Bach1 levels inside the nucleus returned to normal at 4 h after antioxidant treatment in the absence but not in the presence of protein synthesis inhibitor cycloheximide. In addition, antioxidant treatment increased the transcription of Bach1 as shown by pulse chase and real time PCR experiments. Taken together, these results indicate that increased synthesis of Bach1 restored its nuclear levels to normal at 4 h. In conclusion, antioxidant-induced tyrosine 486 phosphorylation leads to nuclear exit of Bach1, thus allowing Nrf2 access to the ARE.
Continuity in fire disturbance between riparian and adjacent sideslope Douglas-fir forests

Abstract Fire-scar and stand-cohort records were used to estimate the number and timing of fire disturbance events that impacted riparian and adjacent sideslope Douglas-fir (Pseudotsuga menziesii (Mirbel) Franco) forests. Data were gathered from 49 stream segments on 24 separate streams on the east slope of the Washington Cascade Range. Upslope forests had more “traceable” disturbance events than riparian forests in each of the valley types with a mean difference of 8–62%. Approximately 55–73% of the total traceable fire disturbance for a stream segment occurred on either sideslope and 24–27% in the riparian forest. Plant association groups in the riparian forest had 25–42% fewer fire disturbance events than the same plant association group upslope. Fewer traceable disturbance events in riparian forests may indicate a reduced disturbance frequency or a more severe disturbance regime or both. The two sideslopes on either side of the riparian forest shared the same fire event in 65 and 54% of the recorded fire events on east/west and north/south sideslopes, respectively. Riparian forests shared fire events with adjacent sideslope forests 58–79% among valley types, and 64–76% among aspects. Shared fire events indicate significant continuity in fire disturbance between riparian and adjacent sideslope forests. Fire disturbance regimes of sideslope and riparian forests are quantitatively different, but interconnected through shared fire disturbance events. Disturbance events play a role in maintaining ecosystem integrity and we suggest that disturbance may need to be planned for in administratively defined riparian buffer strips to protect long-term ecological integrity of riparian and adjacent upslope forests.
Slow light propagation for high optical information density in active photonic lattices

Evanescent field coupling in coupled micro- and nano-laser cavity arrays supports optical modulation waves propagating near the sound speed. The possibility of achieving high information density with near unity delay-time to pulse-time ratio is addressed.
WARMUP IN AVOIDANCE AS A FUNCTION OF TIME SINCE PRIOR TRAINING1

Abstract On avoidance procedures, rats and pigeons typically show warmup effects, characterized by improving performance within sessions and loss of the improvement (“warmup decrement”) between sessions. Between-session losses were examined by varying the time between periods of avoidance training. In one experiment, rats lived fulltime in conditioning chambers while intermission intervals were varied. In a second experiment, the animals lived in home cages between sessions; timeout intervals were introduced at midession, producing recurrence of warmup in the second half-session. In both experiments, the warmup decrements increased substantially as the timeout or intersession intervals were increased from zero to 30 minutes. With intervals of 60 or 120 minutes, the decrements approached or exceeded those obtained with intervals of a day or more. When avoidance was interposed between appetitive sessions, the appetitive responding was disrupted, but this seemed unrelated to the warmup or to the proficiency of avoidance. The warmup in avoidance shares characteristics with transient punishment effects, with the Kamin effect, and with habituation phenomena, but it is premature to assume that they reflect common processes.
Sexually Dimorphic Genome-Wide Binding of Retinoid X Receptor alpha (RXRα) Determines Male-Female Differences in the Expression of Hepatic Lipid Processing Genes in Mice

Many hepatic functions including lipid metabolism, drug metabolism, and inflammatory responses are regulated in a sex-specific manner due to distinct patterns of hepatic gene expression between males and females. Regulation for the majority of these genes is under control of Nuclear Receptors (NRs). Retinoid X Receptor alpha (RXRα) is an obligate partner for multiple NRs and considered a master regulator of hepatic gene expression, yet the full extent of RXRα chromatin binding in male and female livers is unclear. ChIP-Seq analysis of RXRα and RNA Polymerase2 (Pol2) binding was performed livers of both genders and combined with microarray analysis. Mice were gavage-fed with the RXR ligand LG268 for 5 days (30 mg/kg/day) and RXRα-binding and RNA levels were determined by ChIP-qPCR and qPCR, respectively. ChIP-Seq revealed 47,845 (male) and 46,877 (female) RXRα binding sites (BS), associated with ∼12,700 unique genes in livers of both genders, with 91% shared between sexes. RXRα-binding showed significant enrichment for 2227 and 1498 unique genes in male and female livers, respectively. Correlating RXRα binding strength with Pol2-binding revealed 44 genes being male-dominant and 43 female-dominant, many previously unknown to be sexually-dimorphic. Surprisingly, genes fundamental to lipid metabolism, including Scd1, Fasn, Elovl6, and Pnpla3-implicated in Fatty Liver Disease pathogenesis, were predominant in females. RXRα activation using LG268 confirmed RXRα-binding was 2-3 fold increased in female livers at multiple newly identified RXRα BS including for Pnpla3 and Elovl6, with corresponding ∼10-fold and ∼2-fold increases in Pnpla3 and Elovl6 RNA respectively in LG268-treated female livers, supporting a role for RXRα regulation of sexually-dimorphic responses for these genes. RXRα appears to be one of the most widely distributed transcriptional regulators in mouse liver and is engaged in determining sexually-dimorphic expression of key lipid-processing genes, suggesting novel gender- and gene-specific responses to NR-based treatments for lipid-related liver diseases.
Coexpression of 5-HT2A and 5-HT4 receptors coupled to distinct signaling pathways in human intestinal muscle cells

Abstract Background & Aims: The type and function of 5-hydroxytryptamine (5-HT) receptors on intestinal muscle cells in humans are not known. 5-HT receptors were characterized pharmacologically and by radioligand binding. Methods: Contraction, relaxation, inositol 1,4,5-triphosphate (IP 3 ) and adenosine 3′,5′-cyclic monophosphate (cAMP) formation, and 5-HT binding were measured in dispersed muscle cells and in cells in which only one receptor type was preserved by selective receptor protection. Results: 5-HT binding was completely inhibited by 5-HT and partially by 5-HT 2A (ketanserin), 5-HT 4 (SDZ-205,557), and 5-HT 1p ( N -acetyl-5-hydroxytryptophyl-5-hydroxytryptophan amide; 5-HTP-DP) receptor antagonists. 5-HT caused contraction that was inhibited by ketanserin and augmented by SDZ-205,557 and 5-HTP-DP. In the presence of ketanserin, 5-HT caused relaxation of cholecystokinin-contracted cells that was inhibited by SDZ-205,557 and 5-HTP-DP. 5-HT increased IP 3 , which was inhibited by ketanserin, and cAMP, which was inhibited by SDZ-205,557 and 5-HTP-DP. In cells with only 5-HT 2A receptors, 5-HT caused contraction only, and residual binding was inhibited by ketanserin. In cells with only 5-HT45-HT1p receptors, 5-HT caused only relaxation and residual binding was inhibited by SDZ-205,557 and 5-HTP-DP. Conclusions: 5-HT 2A receptors mediating contraction and 5-HT 4 receptors mediating relaxation coexist on human intestinal muscle cells. The 5-HT 4 receptors are closely similar or identical to 5-HT 1p receptors.
SU-E-I-47: Comparison of Risks for Two Medical Imaging Procedures.

Purpose:Radiologists may need to decide which type of image procedure is most appropriate for a particular patient. One factor relevant in making this decision is the relative risk of secondary cancers due to each relevant procedure. Differences in the risk posed by each method are not just due to the total radiationdose imparted by each procedure, but also the distribution of absorbed dose across various organs in the imaging procedure. Two imaging procedures with the same total radiationdose may pose different risks of differential sensitivity to radiation across organs.Methods: New methods of radiationdosimetry enable us to estimate the dose distribution across organs in individual patients. We propose a measure of the relative risk of two medical imaging procedures derived from the hazard function of cancer incidence. The relative risk measure is shown to approximately equal to a weighted sum of the dose difference in each organ. The weights are proportional to organ specific incidence rates. The measure is also sensitive to factors such as the patient's age at exposure to radiation, the attained age and gender, as well as the incidence characteristics of the population to which the patient belongs. We propose to quantify the effects of these factors using information from publically available SEER database for US based patients as well as the LSS study of atomic bomb survivors. The method is illustrated by application to a study comparing chest and abdominal CT scans for a group of pediatric patients. Results: Fig. 1 shows higher absolute relative risk for those exposed at younger ages, with chest scans being riskier for females while abdominal scans were riskier for males. At higher ages, the relative risk is approximately equal. Conclusions: Relative risks can quantify risks comparisons between imaging procedures.
Linear optimal control problems with isoperimetric constraints

Optimum control problems with convex inequality side constraints are studied. It is shown that in quite general circumstances an optimum controller can be obtained, and necessary and sufficient conditions for its determination are derived.
Industrial effluents as a source of mercury contamination in terrestrial riparian vertebrates

Abstract Eight species of piscivorous and insectivorous birds and one species of bat collected along Virginia's North Fork of the Holston River contained elevated mercury residues. The ubiquitous occurrence of mercury in riparian insectivores implicates aquatic insects as a vehicle for spreading mercury contamination from one ecosystem to another and expands the ecological ramifications of mercury-contaminated industrial effluents.
Effects of DEAE-dextran on the partition of red blood cells in aqueous dextran-polyethylene glycol two-phase systems

Abstract Red blood cells of different ages and at least two populations of reticulocytes can be separated by countercurrent distribution in one of the buffered, aqueous two-phase systems containing dextran and polyethylene glycol. Rabbit red cells which are the most extensively studied in the current literature do not partition in these systems because of their low surface charge. We now report that the addition of small quantities of the cationic polymer DEAE-dextran to some of the previously used phase systems containing non-ionic polymers permits the distribution of low-charged cells (as exemplified by rabbit red cells). As a consequence we have been able to resolve rabbit red cells of different ages by countercurrent distribution. While dog red cells (which have a high surface charge) have larger partition coefficients than rabbit cells in phase systems with or without DEAE-dextran, we have found that a number of other generalities that apply to phase systems containing dextran and polyethylene glycol are reversed by the presence of DEAE-dextran. Thus, an increase in the salt ratio of NaCl/phosphate in a given phase system does not diminish the partition coefficients but instead increases them. The substitution of K+ salts by Na+ salts by Li+ salts in the phase systems also no longer leads to an increase in the partition coefficients but rather to a diminution.
Language Modeling for Determiner Selection

We present a method for automatic determiner selection, based on an existing language model. We train on the Penn Tree-bank and also use additional data from the North American News Text Corpus. Our results are a significant improvement over previous best.
NANOLEX: A FORTRAN program for accurate analysis of particle induced X-ray spectra

Abstract A FORTAN program, NANOLEX, has been developed for the analysis of particle induced X-ray spectra. Background components are stripped from a spectrum and recursive relations are employed to strip away contributions of non-Gaussian peak components. A technique known as linearization of a Gaussian is used to determined an energy scale and a good estimate of peak intensities. Ideal Gaussian spectra are generated for elements in the sample and a Fletcher-Powell optimization method is used in a linear least-squares fitting of ideal spectra to the stripped experimental spectrum. The program has been developed with both small and large computer versions.
Evolution of photospheric magnetic field patterns during skylab

The evolution of the photospheric magnetic field pattern over eleven solar rotations preceding a minimum of the activity cycle is shown to be characterized by abrupt changes of the dominant geometrical patterns of the field. These changes are associated with the onset and end of a sudden increase in the calculated total energy content of the field, which is otherwise decreasing through the period. The calculated geometrical rearrangements correspond in time to observed restructurings of the corona, the interplanetary field, and the solar rotation pattern.
Cloning and characterization of genes encoding α and β subunits of glutamate-gated chloride channel protein in Cylicocyclus nassatus ☆

The invertebrate glutamate-gated chloride channels (GluCls) are receptor molecules and targets for the avermectin-milbemycin (AM) group of anthelmintics. Mutations in GluCls are associated with ivermectin resistance in the soil dwelling nematode Caenorhabditis elegans and the parasitic nematode Cooperia oncophora. In this study, full-length cDNAs encoding alpha and beta subunits of GluCl were cloned and sequenced in Cylicocyclus nassatus, a common and important cyathostomin nematode parasite of horses. Both genes possess the sequence characteristics typical of GluCls, and phylogenetic analysis confirms that these genes are evolutionarily closely related to GluCls of other nematodes and flies. Complete coding sequences of C. nassatus GluCl-alpha and GluCl-beta were subcloned into pTL1 mammalian expression vector, and proteins were expressed in COS-7 cells. Ivermectin-binding characteristics were determined by incubating COS-7 cell membranes expressing C. nassatus GluCl-alpha and GluCl-beta proteins with [(3)H]ivermectin. In competitive binding experiments, fitting the data to a one site competition model, C. nassatus GluCl-alpha was found to bind [(3)H]ivermectin with a high amount of displaceable binding (IC(50)=208 pM). Compared to the mock-transfected COS-7 cells, the means of [(3)H]ivermectin binding were significantly different for C. nassatus GluCl-alpha and the Haemonchus contortus GluCl (HcGluCla) (p=0.018 and 0.023, respectively) but not for C. nassatus GluCl-beta (p=0.370). This is the first report of orthologs of GluCl genes and in vitro expression of an ivermectin-binding protein in a cyathostomin species. These data suggest the likelihood of a similar mechanism of action of AM drugs in these parasites, and suggest that mechanisms of resistance may also be similar.
Lipid–Protein Interactions: Enhancement of Enzyme Activity of L-Glutamic Acid Dehydrogenase by Nonionic Detergents

Five nonionic detergents enhanced the activity of L-glutamic acid dehydrogenase [L-glutamate:nicotinamide adenine dinucleotide phosphate oxidoreductase (deaminating) (EC 1.4.1.3)]. These detergents activated the enzyme toward α-ketoglutaric acid reduction, causing a decrease in the sensitivity of the enzyme to allosteric regulation by guanosine 5-triphosphate. There was also a diminution of the enhancing effect of the modifier adenosine 5-diphosphate on the enzyme's L-glutamic acid dehydrogenase activity. These detergents may cause a conformational change in the enzyme, and this change could lead to an increase in the binding of the substrates for the α-ketoglutaric acid reduction. Accompanied with this conformational change would be a decrease in the binding of the modifier guanosine 5′-triphosphate, with no concomitant change in the binding of the adenosine 5′-diphosphate modifier.
Intermolecular coupling between loop 38-52 and the C-terminus in actin filaments.

The recently reported structural connectivity in F-actin between the DNase I binding loop on actin (residues 38–52) and the C-terminus region was investigated by fluorescence and proteolytic digestion methods. The binding of copper to Cys-374 on F- but not G-actin quenched the fluorescence of dansyl ethylenediamine (DED) attached to Gin-41 by more than 50%. The blocking of copper binding to DED-actin by N-ethylmaleimide labeling of Cys-374 on actin abolished the fluorescence quenching. The quenching of DED-actin fluorescence was restored in copolymers (1:9) of N-ethylmaleimide-DED-actin with unlabeled actin. The quenching of DED-actin fluorescence by copper was also abolished in copolymers (1:4) of DED-actin and N-ethylmaleimide-actin. These results show intermolecular coupling between loop 38–52 and the C-terminus in F-actin. Consistent with this, the rate of subtilisin cleavage of actin at loop 38–52 was increased by the bound copper by more than 10-fold in F-actin but not in G-actin. Neither acto-myosin subfragment-1 (S1) ATPase activity nor the tryptic digestion of G-actin and F-actin at the Lys-61 and Lys-69 sites were affected by the bound copper. These observations suggest that copper binding to Cys-374 does not induce extensive changes in actin structure and that the perturbation of loop 38–52 environment results from changes in the intermolecular contacts in F-actin.
Doubts about the Future of the Private Liberal Arts Junior College.

After strengths and weaknesses are tallied and economic and demographic trends factored in, is there a future for the eighty-nine remaining private liberal arts junior colleges in the United States?
Some properties of a lipid mobilizing substance from the calf mid-brain.

Abstract 1. 1. A substance with lipid mobilizing properties has been isolated from the calf mid-brain. 2. 2. The lipid mobilizing factor was chromatographically, electrophoretically and spectroscopically similar to hypoxanthine, but differed from the purine in solubility and in lipolytic properties. 3. 3. The incubation medium retained lipid mobilizing properties following tissue exposure, and the tissue retained some lipolytic activity after exposure to the lipid mobilizing factor. 4. 4. A parallelism existed between the relationship of the mid-brain lipid mobilizing factor and adrenergic blocking agents, and epinephrine and adrenergic blocking agents with respect to lipid mobilization. 5. 5. An inhibitor of lipid mobilization also was present in the crude mid-brain extract. The inhibitor, after separation from the lipid mobilizing component, suppressed the lipolytic activities of the purified mid-brain extract and the catecholamines (epinephrine and norepinephrine).
TU-B-I-618-02: Converting the Radiology Department From Film-Screen to Digital — Making the Transition

In recent years, Picture Archiving and Communications Systems have begun to proliferate in the medical community. This is a result of technical advances that have occurred in two areas — advances in computer technology (such as storage density, processing speeds, network bandwidth, compression techniques, and so on), and the maturation of robust standards for communication and transmission of medical images and information (Standards like HL-7, DICOM, and IHE). In parallel with these developments, the medical imaging equipment and information systems vendors have been developing robust software implementations and more advanced system architecture to take advantage of this emerging technology and these robust standards. As a result of this revolutionary change in the way we operate, it has become increasingly important that we in the Medical Physics community modify our approach to the type of support we bring to these operations accordingly. This presentation will focus on some of the issues the Medical Physicist is likely to face when supporting a clinical operation that is undergoing (or is about to undergo) a conversion from film-screen base radiography to digitally acquired images. It will cover the educational needs of the Medical Physicist, radiologists and technical staff, how to use photostimulable phosphor imaging to introduce a radiology department to digital imaging, the importance of Modality Work List Management in the filmless radiology environment, selection of a DDR system for clinical use, weaning the referring clinicians off of film and what issues are important to achieving this, quality control programs for digital imaging systems, and finally those features of the radiology reading room environment that are important for soft-copy interpretation.
Tissue-Specific Expression of Messenger Ribonucleic Acids for Insulin-Like Growth Factors and Insulin-Like Growth Factor-Binding Proteins during Perinatal Development of the Rat Uterus

Insulin-like growth factor (IGF)-I and IGF-II play a number of important roles in growth and differentiation, and IGF-binding proteins (IGFBPs) modulate IGF biological activity. IGF-I has been shown previously to be essential for normal uterine development. Therefore, we used in situ hybridization assays to characterize the unique tissue- and developmental stage-specific pattern of expression for each IGF and IGFBP gene in the rat uterus during perinatal development (gestational day [GD]-20 to postnatal day [PND]-24). IGF-I and IGFBP-1 mRNAs were expressed in all uterine tissues throughout this period. IGFBP-3 mRNA was not detectable at GD-20 but became detectable beginning at PND-5, and the signal intensity appeared to increase during stromal and muscle development. IGFBP-4 mRNA was abundant throughout perinatal development in the myometrium and in the stroma, particularly near the luminal epithelium. IGFBP-5 mRNA was abundantly expressed in myometrium throughout perinatal development. IGFBP-6 mRNA was detected throughout perinatal development in both the stroma and myometrium in a diffuse expression pattern. IGF-II and IGFBP-2 mRNAs were not detected in perinatal uteri. Our results suggest that coordinated temporal and spatial expression of IGF-I and its binding proteins (IGFBP-1,-3,-4,-5, and -6) could play important roles in perinatal rodent uterine development.
Cannot Earthquakes Be Predicted

Robert J. Geller et al. are on shaky ground when they state, in the title of their Perspective ([1][1]), that earthquakes cannot be predicted. In spite of their advice, we should not stop studying the physics of preparation for catastrophic rupture, in the field, the laboratory, and theoretically;
Dihydroflavonol sweeteners and other constituents from Hymenoxys turneri

Abstract From the above ground parts of Hymenoxys turneri , three unusual 2,3-dihydroflavonol 3-acetates, two other 2,3-dihydroflavonols, two flavones and three sesquiterpene lactones were obtained. Their structures were established by spectroscopy. The dihydroflavonol acetates and dihydroflavonols were assessed for their sweetness intensity by a taste panel.
Off-diagonal magnetoelectric susceptibility in single crystal Cr 2 O 3

Previous studies of magnetoelectric effect in Cr 2 O 3 employed collinear electric and magnetic fields along the rhombohedral c axis or perpendicular to it. They determined the diagonal elements of the rhombohedral magnetoelectric susceptibility tensor, i.e., α 33 and α 11 , respectively. This study applied orthogonaI electric and magnetic fields and determined for the first time the off-diagonal element α 12 by the measurement of the dielectric constant. Changes in the dielectric constant of Cr 2 O 3 were studied as a function of applied magnetic field. This relationship was found to be linear. At 8 kOe, orthogonal electric and magnetic field conditions were applied from room temperature to the Neel point (307 K) at frequencies of 1, 5, and 10 kHz. Changes in dielectric constants showed two maxima within the temperature range. By the use of equations for α 33 and α 11 given by Rado, the values for α 12 were obtained from the dielectric constant data. The temperature plot of α 12 , as shown below, showed two peaks in the neighborhood of the Neel point. The α 12 values vanished beyond this temperature range. From the symmetry consideration, off-diagonal α 12 values can only exist in Cr 2 O 3 when there are antiferromagnetic domains and the inter-domain walls lower the symmetry. The two peaks of α 12 are additional evidence for the existence of domains in Cr 2 O 3 .
Ampulla of Vater/duodenal wall spasm diagnosed by antroduodenal manometry.

Patients with chronic epigastric to right upper quadrant pain are often considered to have gallbladder or sphincter of Oddi dysfunction, but standard tests are nondiagnostic. In 62 consecutive patients with this complaint undergoing antroduodenal manometry, we correlated a change in duodenal motility with spasm of the ampulla of Vater/duodenal wall. This distinctive motility pattern occurred and was analyzed in 35% of patients. It is characterized by increased duodenal wall tone with phasic contractions of 19–22 or 41–44 contractions/min or by phasic activity alone. The subjects with spasm also underwent cholecystokinin cholescintigraphy, and 50% showed either significantly delayed gallbladder emptying or hilum to small intestine emptying, or both. The disorder appears to be secondary to a loss of neural inhibitory control and a dysfunctional small-bowel pacemaker. Antroduodenal manometry is an essential diagnostic procedure that complements sphincter of Oddi manometry in evaluation of unexplained right upper quadrant pain.
Exploring the Trafficking, Ligand-Binding Activity, and Unfolding of a Model GPCR

G protein-coupled receptors (GPCRs) are integral membrane proteins vital for cellular signaling and constitute one of the major drug targets. Despite their importance, relatively little information regarding their structure, folding, and stability has been published.This work describes the impact of disulfide bonds on the expression and structural stability of the human adenosine receptor, A2A (hA2AR). The crystal structure of this receptor revealed four disulfide bonds present in extracellular loops that could contribute to expression, stability, or ligand binding or to a combination of these.To test the role of these residues, cysteine to alanine mutants of hA2AR were created; expression and ligand-binding activity of the constructs were tested in mammalian (HEK293) and yeast (Saccharomyces cerevisiae) cells. Once purified from yeast, unfolding of the hA2AR through thermal and chemical means was monitored via intrinsic tryptophan fluorescence and circular dichroism. The effect of ligand addition and reduction of disulfide bonds was also investigated.Thermal and chemical denaturation were not reversible, yet clear differences in the unfolding behavior were observed upon ligand binding via circular dichroism and fluorescence spectrometry. We found that the stability of hA2AR was increased upon incubation with the agonist N6-cyclohexyladenosine or the antagonist theophylline. When extracellular disulfide bonds were reduced with a chemical reducing agent, the ligand binding activity decreased by ∼40%, but reduction of these bonds did not compromise the unfolding transition observed via urea denaturation. Overall, these approaches offer a general strategy for characterizing the effect of disulfide bonds and ligand effects on the stability of GPCRs.
A comparison of four prenatal care indices in birth outcome models: Comparable results for predicting small-for-gestational-age outcome but different results for preterm birth or infant mortality

Abstract Objective Several different indices of prenatal care have been used in birth outcome models to analyze the relationship between the adequacy of prenatal care and low birthweight, preterm birth, and infant mortality. This investigation compared the performance of the Kessner index, the GINDEX, the adequacy of prenatal care utilization (APNCU) and certain variants of the APNCU in such outcome models. Study Design and Setting Data from National Center for Health Statistics' (NCHS) Linked Birth and Infant Death Cohort files were used in multivariate logistic regression models to estimate adjusted odds ratios comparing different prenatal care utilization categories for each index. Results When the indices were used in small-for-gestational-age outcome models, the conclusions suggested by the various indices were similar. In models for preterm birth and infant mortality, by contrast, the various indices gave widely differing results. Unlike the use of other indices, the use of the GINDEX paradoxically suggested that birth outcomes were better in the inadequate, intermediate, and intensive categories than in the adequate category. Conclusion The conclusions drawn concerning the association between prenatal care utilization and small-for-gestational-age seem relatively robust in the sense of being consistent across indices. In analyzing associations between prenatal care and preterm birth or infant mortality, care must be taken in choosing indices, because results differ substantially across indices.
When a gold standard is made of tin

In this issue of Blood , Kantarjian and colleagues analyze the outcome of intensive, cytarabine-based induction chemotherapy in the management of elderly patients with newly diagnosed AML treated over an 18-year period, and challenge whether standard, available therapy should ever be offered to a