cssi/SciSciGPT-SciSciNet huggingface dataset:
A versatile means of intracellular labeling: injection of biocytin and its detection with avidin conjugates

Abstract Biocytin is a biotin-lysine complex of low molecular weight containing about 65% biotin, which retains a high affinity for avidin. Since the latter molecule has been conjugated to several histochemical markers, the use of biocytin as an intracellular marker was investigated. Electrodes were filled with a solution of 4–6% biocytin dissolved in 0.5 M KCl and 0.05 M Tris buffer. pH 7–7.6. Neurons were recorded intracellularly in the supraoptic nucleus of an explant preparation of the rat supraoptico-neurohypophysial system and injected for 1–20 min with either hyperpolarizing or depolarizing current. Following variable recovery times, the explants were fixed in either 10% formalin or 4% paraformaldehyde overnight, sectioned on a vibratome, and incubated with the avidin biotin complex (ABC) or avidin which had been conjugated to fluorescein, rhodamine, Texas Red or horseradish peroxidase and containing 1% Triton-X 100. A high percentage of injected neurons were recovered using each of the labels with about equal success. Both negative or positive current injection could be used with little electrode clogging. Labeling with fluorescent conjugates was qualitatively similar to that of Lucifer Yellow, whereas labeling with avidin coupled to horseradish peroxidase or with ABC was qualitatively similar to filling neurons directly with horseradish peroxidase. The advantages of this technique are the ease of injection of biocytin and the versatility in allowing the investigator to choose among light-emitting and light-absorbing images.
A characterization of lambda definability in categorical models of implicit polymorphism

Lambda definability is characterized in categorical models of simply typed lambda calculus with type variables. A category-theoretic framework known as glueing or sconing is used to extend the Jung-Tiuryn (1993) characterization of lambda definability first to ccc models, and then to categorical models of the calculus with type variables.
Decreased mitogen activated protein kinase activities in congenital diaphragmatic hernia–Associated pulmonary hypoplasia

Abstract Background/Purpose: The mechanisms that cause pulmonary hypoplasia associated with congenital diaphragmatic hernia (CDH) currently are unknown. The authors proposed that the reduced size and immaturity of these lungs may be associated with differences in the levels of mitogen activated protein (MAP) kinase phosphorylation (extracellular signal regulated protein kinases, ERK-1 and -2). Methods: ERK-1 activities were measured using immune-complex kinase assays on fetal whole-lung lysates obtained from both nitrofen and olive oil–treated (control) pregnant rats. In addition, ERK-1 and ERK-2 functional activities were estimated by semiquantitative Western blot analysis, using an antibody specific for the diphosphorylated (dp-ERK, activated) forms of the enzymes. Results: ERK-1 activities, measured using immune-complex kinase assays, were reduced in CDH lungs compared with olive oil–treated controls ( P P = .003; dp-ERK-2, P = .04), whereas ERK-1 and ERK-2 protein levels were unchanged. Conclusions: The lower values of ERK-1 activity and reduced amounts of dp-ERK-1 and dp-ERK-2 in lung tissue from CDH animals, suggests that ERK-1 and ERK-2 activities are reduced in pulmonary hypoplasia associated with CDH. The observed reduction in ERK-1 and ERK-2 activities implicates attenuated cell signaling upstream of the ERK-1 and -2 enzymes. J Pediatr Surg 36:1490-1496. Copyright © 2001 by W.B. Saunders Company.
The glycans of horseradish peroxidase

Abstract Horseradish peroxidase (E.C. 1.11.1.7) isozyme c (HRPc) is a glycoprotein found to contain 21.8% carbohydrate with the average composition: 2 mol GlcNAc, 2.6 mol Man, and 0.8 mol each of Fuc and Xyl. The oligosaccharides of HRPc were investigated by a combination of High pH Anion-Exchange Chromatography with Pulsed Amperometric Detection, methylation analysis and Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry. The structure of the major oligosaccharide released by digestion with glycopeptidase A, accounting for between 75 and 80% of the total, was confirmed to be α -Man-(1 → 6)[ α -Man-(1 → 3)][ β -Xyl-(1 → 2)]- β -Man-(1 → 4)- β -GlcNAc-(1 → 4)[ α -Fuc-(1 → 3)]-GlcNAc. Most of the remaining oligosaccharides were found to belong to the (Xyl) x Man m (Fuc) f GlcNAc 2 ( m = 2, 4, 5, 6; f = 0 or 1; x = 0 or 1) family. Less than 5% of the oligosaccharides were of the Man m GlcNAc 2 ( m = 4 to 7) type. Methylation analysis of holo- and apo-HRPc and its tryptic glycopeptides support the structures proposed for the oligosaccharides. Furthermore, methylation analysis of the tryptic glycopeptides provides evidence for the heterogeneity of the oligosaccharides occurring at each of the N -linked sites.
Can one mix two non-specific antisera and obtain a specific radioimmunoassay?

Sekihara et al. have proposed that it is possible to combine two antisera, each of which is unsatisfactory for a clinical radioimmunoassay due to cross-reactivity problems, and obtain an assay which is of sufficiently good specificity for practical application. The present report provides a theoretical analysis of this problem in a "reduced" case of minimal complexity. We assume infinitesimal concentration of tracer, equilibrium of reactants, perfect separation of bound and free, and that each of the two antisera contain only a single class of antibody sites which can bind to the desired ligand or to a cross-reacting species. Numerical methods are used to generate "ideal" dose response curves. The specificity is evaluated by three criteria: 1) as the ratio of ligand concentrations resulting in 10 or 50% reduction of binding of labeled ligand to antibody, i.e. %B/BO = 90 or 50%; 2) the %B/BO or %B/T at an arbitrary dose level; or 3) the apparent amount of ligand present, for an arbitrary dose of crossreacting ligand. Results indicate that mixing of two nonspecific antisera (each cross-reacting with a different ligand) results in a radioimmunoassay system with a specificity intermediate between that obtained with either of the antisera used alone. Whether this will provide a "satisfactory" assay depends on the purposes for which it is intended, the expected concentrations of cross-reacting ligands, etc. Computer simulation studies may be utilized to select the optimal ratio of the two antisera being used for the assay.
The precipitation of poly‐L‐glutamic acid. II. β‐Precipitation

Studies have been made of the precipitation of poly-L-glutamic acid from dilute aqueous solutions, over the pH range where the α-helical conformation is maintained. The major purpose is to establish the molecular conformation in the precipitate and to outline the mechanism of the precipitation. Utilizing molecular-weight fractions, it is shown that there are two distinctly different precipitation regions, which depend on temperature, concentration, and pH. In one of these regions, the α-region, a variety of physical properties demonstrate that precipitation occurs without any conformational change. The temperature coefficient of the precipitation process in this region indicates that it is nucleation-controlled.
Role of angiotensin II and AT1 receptors in hippocampal LTP

Results of a previous study showed that angiotensin II (AII) inhibited the induction of long-term potentiation (LTP) in hippocampal granule cells in response to dorsomedial perforant path stimulation in urethane-anesthetized rats. The results of present experiments demonstrate a dose-dependent inhibition of LTP induction under the same conditions due to ethanol (EtOH) administered by stomach tube and diazepam (DZ) injected IP. The inhibition of LTP induction by EtOH and DZ can be blocked by saralasin (SAR) applied directly to the dorsal hippocampus and by lorsartan (DuP 753) administered IP. Lorsartan or a metabolite crosses the blood-brain barrier because it also blocks the inhibition of LTP induction due to AII administration directly into the dorsal hippocampus. Lorsartan is a competitive antagonist of the AT1 subtype AII receptor. Therefore, the AII and the EtOH and DZ inhibition of LTP induction are mediated by the AII subtype receptor AT1. AIII and the AT2 antagonist PD123319 did not produce any significant effects. These in vivo effects can be reproduced in brain slices and therefore cannot be attributed to other factors, such as the urethane. In addition, electrical stimulation of the lateral hypothalamus (LH) inhibits LTP induction, and the inhibition can be blocked by SAR. These data on LH stimulation indicate that LH AII-containing neurons send axons into the hippocampus that inhibit the induction of LTP. These results not only provide new information on a neurotransmitter involved in the amnesic effects of benzodiazepines and ethanol-induced memory blackouts, but also testable hypotheses concerning recent observations that angiotensin converting enzyme (ACE) inhibitors elevate mood and improve certain cognitive processes in the elderly.
Identification of novel angiogenesis inhibitors

Vascular endothelial growth factor (VEGF) is a key stimulant of angiogenesis, which is the process of generating new capillary blood vessels. Inhibition of the vascular endothelial growth factor receptor (VEGFR) kinase is known to result in blockage of angiogenesis. A pharmacophore was developed based on the binding of ATP to the hinge region of the kinase domain of VEGFR and a database search of 18,000 compounds was conducted. Selected hits were assessed for their ability to limit the induction of web-like network of capillary tubes by the human umbilical vascular endothelial cells. Two compounds (1 and 4) showed good inhibitory ability to prevent sprouting and closed polygon formation of the tubular networks, promising them to be lead compounds. Compound 4 showed 60% inhibition at 0.05 μM.
Logistic Regression, Survival Analysis, and the Kaplan-Meier Curve

Abstract We discuss the use of standard logistic regression techniques to estimate hazard rates and survival curves from censored data. These techniques allow the statistician to use parametric regression modeling on censored data in a flexible way that provides both estimates and standard errors. An example is given that demonstrates the increased structure that can be seen in a parametric analysis, as compared with the nonparametric Kaplan-Meier survival curves. In fact, the logistic regression estimates are closely related to Kaplan-Meier curves, and approach the Kaplan-Meier estimate as the number of parameters grows large.
Can rofecoxib delay a diagnosis of Alzheimer's disease in patients with mild cognitive impairment?

Original article Thal LJ et al. (2005) A randomized, double-blind, study of rofecoxib in patients with mild cognitive impairment. Neuropsychopharmacology 30: 1204–1215 PubMed Clinical studies have failed to show convincing effects of nonsteroidal anti-inflammatory drugs (NSAIDs)—including the selective cyclo-oxygenase 2 (COX2) inhibitor rofecoxib—on the progression of Alzheimer's disease (AD).
Evaluation of tungsten carbide as the electrocatalyst support for platinum hydrogen evolution/oxidation catalysts

Abstract WC was investigated as an electrocatalyst support material for a monolayer-equivalent of Pt and the Pt/WC system was evaluated as an electrocatalyst for the HER and HOR and compared to commercial Pt/C. It was found that Pt/WC lost only 4% of its activity during aging, which was significantly better than Pt/C, which lost more than 20% of its activity under identical operating conditions. Most of the degradation of the Pt/WC performance was due to the decomposition of impurity WOx species on the support surface from synthesis that was identified by XPS. The activity and mechanism for the HER and HOR were also quantitatively evaluated. It was found that the reaction kinetics for the HER and HOR in both catalyst systems, Pt/WC and Pt/C, were identical, proceeding through the Volmer–Heyrovsky mechanism with an apparent activation energy of approximately 35 kJ/mol.
Generating Interest for Engineering in Early Childhood Education Through a Book About Dissection

In today’s world, it is critical to continually improve and develop new educational practices. Compared to developed and developing countries around the world, especially in science, mathematics, and engineering, the United States is falling behind. One of the most prominent reasons is the lack of interest in these subjects. In order to reverse this trend, it is important to develop new ways to creatively spark interest in engineering and natural sciences early on in a student’s educational career. The scope of this project was to develop a children’s book that introduced mechanical dissections. Along with the book, an in class presentation was developed for early elementary students in Kindergarten and 1st grade, with the goal of inspiring interest in engineering as a whole. This presentation was then used in local elementary school classrooms to gauge how such a program would fare in a typical elementary level classroom. Overall the project produced successful results. Not only were the students intrigued and excited to see the presentation, but they also learned more of the information than was originally expected. Through different media, the students were able to explore and question how and why a household appliance worked. This interaction with engineering concepts at a young age could prove to be very beneficial in the future.Copyright © 2011 by ASME
Changes in Precipitation Extremes in the Hawaiian Islands in a Warming Climate

For the first time, trends of five climate change indices related to extreme precipitation events in the HawaiianIslands areinvestigated usingdailyobservational recordsfromthe1950sto2007. Fourindices [simple daily intensity index (SDII), total number of day with precipitation $25.4 mm (R25), annual maximum consecutive 5-day precipitation amount (R5d), and the fraction of annual total precipitation from events exceedingthe 1961‐9095thpercentile(R95p)] describethe intensity(SDII),frequency(R25),andmagnitude (R5d and R95p) of precipitation extremes, and the fifth index [consecutive dry days (CDD)] describes drought conditions. The annual probability density functions (PDFs) of precipitation indices for two epochs (i.e., 1950‐79 and 1980‐2007) are analyzed. Since the 1980s, there has been a change in the types of precipitation intensity, resulting in more frequent light precipitation and less frequent moderate and heavy precipitation intensity. The other three precipitation-related indices (R25, R5d, and R95p) demonstrate a shift toward the left of the distribution over time, suggesting shorter annual number of days with intense precipitation and smaller consecutive 5-day precipitation amounts and smaller fraction of annual precipitation due to events exceeding the 1961‐90 95th percentile in the recent epoch relative to the first epoch. The changes of PDF distribution for SDII, R25, R5d, and CDD are significant at the 5% level according to a two-sample Kolmogorov‐Smirnov test. A nonparametric trend analysis is then performed for four periods, with different starting years (e.g., the 1950s, the 1960s) but the same ending year (2007). Long-term downward trends are evident for four precipitation-relatedindices,andlong-termupwardtrendsareobservedforCDD.Geographically,Kauaiand Oahu are dominated by long-term decreasing trends for four precipitation-related indices, while increasing trends play the major role over the island of Hawaii. The upward trends of drought conditions in the long run are predominant on all the major Hawaiian Islands. To investigate whether the trends are stable throughout the time, the derivatives of trends for each of the 30-yr running series are calculated (e.g., 1950‐79, 1951‐80, ... , 1978‐2007) for four precipitation-related indices at each station. For Kauai andOahu, positivederivatives prevailfor all indicesin the presenceof longterm negative trends, suggestive of a phase change in precipitation extremes and such extremes showing an upswingrecently.FortheislandofHawaii,thereisalsoanindicationofphasereversaloverthelast60 yr,with negative derivatives occurring in the presence of the background positive trends. Apositiverelationshipisfoundbetweentheprecipitation indicesandtheSouthernOscillationindex(SOI), �� �� �� ,
Effect of Estrogen/Progestin Potency on Lipid/Lipoprotein Cholesterol

We studied 374 women taking oral contraceptives, 284 women taking estrogen preparations after menopause, and 1086 women taking no hormones, to determine the relation of plasma lipids and lipoprotein cholesterol concentrations to various types of estrogen/progestin formulations. Premenopausal women, using oral contraceptives containing a relatively low dose of estrogen combined with a medium or high dose of progestin (Norlestrin, Ovral, or Demulen) had a 24 per cent higher median concentration of low-density-lipoprotein cholesterol than did those not using hormones (P less than 0.05). Women using oral contraceptives that are high in estrogen and low in progestin (Enovid or Oracon) had significantly higher concentrations of high-density-lipoprotein cholesterol than did nonusers; those using Ovral, a low-estrogen and high-progestin formulation, had significantly lower levels of high-density-lipoprotein cholesterol. In postmenopausal women the use of estrogen was associated with concentrations of low-density-lipoprotein cholesterol that were 11 to 19 per cent below the levels in postmenopausal women who did not use hormones. The effects of estrogen-progestin balance on low-density and high-density lipoproteins may underlie the increased incidence of stroke and myocardial infarction in women of childbearing age who take oral contraceptives.
The scattering of fast neutrons from W184

Neutrons with energies of 0.3 to 1.5 MeV are scattered from W184. Pulsed-beam fast time-of-flight techniques including a magnetic bunching system are utilized to resolve the elastically scattered neutrons from those inelastically scattered. The differential elastic cross section is measured at 50 keV intervals with an ≈20 keV incident neutron energy spread. The differential cross sections for inelastic scattering resulting in the excitation of residual nuclear levels at 111±5, 365±10, 690±40, 900±25, 1000±30, and 1120±30 keV are determined. In all instances the inelastically scattered neutrons are emitted, within experimental error, isotropically. The experimental results are compared with those obtained in previous work and with the predictions of theory.
Microstructure Development in Unsupported Thin Films

To better understand the role of the substrate in the microstructural evolution of thin films, unsupported nanocrystalline yttrium-stabilized zirconia (ZrO2:16%Y or YSZ) films were examined as a function of temperature and annealing time. Grain growth, texturing, and pinhole formation were measured using transmission electron microscopy (TEM) and electron diffraction. Films were produced and subsequently annealed on metallic grids using a previously developed technique that results in near full density films at low annealing temperatures. Microstructural evolution in these films was unique compared with constrained films. Grains were found to spheroidize much more readily, ultimately resulting in the formation of porosity and pinholes. Grain growth was found to stagnate at a size particular to each annealing temperature, presumably due to the effects of Zener pinning. It is proposed that the lack of substrate strain and confinement effects allows for the dominance of surface energetics with respect to microstructural evolution.
Stable isotope signatures associated with palaeosols, Pennsylvanian Holder Formation, New Mexico

The Holder Formation (Pennsylvanian, Virgilian) of southern New Mexico, USA, consists of limestones interbedded with siliciclastics. It was deposited during times of glacio-eustatic sea-level change and was exposed subaerially during multiple sea-level lowstands. Microcomponents and whole-rock samples of limestones were analysed for δ13C and δ18O values to examine the method of whole-rock isotopic analysis for detecting subaerial exposure events and to determine the diagenetic processes acting during subaerial exposure. Whole-rock isotopic shifts are not consistently present across petrographically identified subaerial exposure surfaces. Apparently, whole-rock isotopic shifts do not result from wholesale replacement of the host sediment during soil formation. However, the isotopic shifts are present in calcareous, soil-precipitated microcomponents, such as rhizoliths, laminated crusts, and soil-precipitated cements. The components are heterogeneous in isotopic composition, but converge on a meteoric calcite line at about δ18O=−5.5‰. These microcomponents are heterogeneous in distribution and may either dominate or be a minor constituent of the whole rock at a single stratigraphic horizon. Without petrographic selection of palaeosol components, the detection of whole-rock isotopic shifts may depend on the selection or chance sampling of a rock containing abundant microcomponents precipitated in a soil environment. Only minor whole-rock isotopic shifts come from those rocks bearing no evidence of exposure and bearing lithological characteristics suggesting subaerial exposure was unlikely.
Ultrasound-guided parasacral approach to the sciatic nerve block in children.

SummaryBackground The parasacral (PS) approach to sciatic nerve blockade has the potential for safe and effective use in children, but has never been studied in this population. Its potential advantages include increased posterior cutaneous nerve block reliability, potential for hip joint analgesia, and decreased nerve depth, making ultrasound guidance easier. Objective To assess the efficacy of an ultrasound-guided PS sciatic nerve block in children. Methods Nineteen patients, 1–16 years old, scheduled for lower limb surgery with peripheral nerve blockade (PNB) were prospectively enrolled. A PS sciatic block was performed using both ultrasound guidance and nerve stimulation, and 0.5 ml·kg−1 ropivacaine 0.2% (maximum 20 ml) was administered. Patient demographics, the time to perform the block, the lowest intensity of nerve stimulation, evoked response, identification of gluteal arteries, and amount of narcotic given were recorded. Postoperatively, pain scores, block success or failure, block duration, and complications were recorded. Results The block was performed using the PS approach in 95% of the cases. The success rate was 100% in the PS sciatic blocks performed. The pain scores for all patients in the first postsurgical hour were zero, except one patient that had a pain score of 3 of 10 at 30 min; his pain improved to 0 of 10 after administration of one dose of fentanyl and distraction techniques. The blocks lasted 17.3 ± 5.4 h. No complications were identified. Conclusion The PS approach is an effective option for sciatic nerve blockade to provide postoperative pain relief in children having lower extremity surgery.
Violent oxidation of lithium-containing aluminum alloys in liquid oxygen

Abstract A strong exothermic and quite well known thermite reaction involving aluminum, oxygen and transition metals (Fe, Cr, Ni, etc.) has apparently been initiated during impact testing of Alcoa aluminum alloy #2090 in liquid oxygen at NASA-MSFC. In some instances, this reaction, essentially an oxidation process, has been so intense that the Inconel 718 cup containing the aluminum alloy disk and associated impacter has melted raising certain safety concerns in the use of this alloy. Reaction products as well as the test specimen surfaces have been studied with surface science techniques like XPS/ESCA, SIMS and AES. Typically, in order to initiate the thermite reaction a temperature of approximately 1000°C is necessary. The mechanism responsible for this oxidation is of great interest. The analysis of the reaction products together with a theoretical analysis, including digital modeling has been pursued. There is strong evidence that the large relaxation energy of the aluminum oxide coating, formed during the aluminum alloy cleaning process, is causing a highly localized energy release during fracture or lattice deformation which is enhancing the oxidation process to a runaway condition. The presence of alkali atoms (Li) enhances the likelihood and intensity of the oxidation reaction. The details of the surface studies will be discussed.
Microenvironmental influences in melanoma progression

An often overlooked facet of tumor biology research is the involvement of the surrounding tumor microenvironment. Increasing evidence is being presented to support a major role for stromal components in all stages of tumorigenesis including initiation, progression, and metastasis. Melanoma serves as a model for studying cellular and stromal interactions within the tumor microenvironment due to the array of cell types localized to these lesions. Here, we discuss the both the molecular mechanisms, as well as the extracellular and contextual input that contribute to melanoma progression. Special emphasis is given to the assorted cell types and their interactions with the extracellular matrix and adjacent cells. Melanoma progression also initiates development of intralesional hypoxic regions; the relative significance of hypoxia in disease is also addressed. Lastly, a number of laboratories are currently developing innovative strategies to study melanoma within a microenvironmental platform. These promising model systems and their potential for closing current gaps in knowledge of disease are reviewed. The development of such models holds translational value that cannot be achieved with most current systems.
Tetrahedral-site copper in chalcogenide spinels

Abstract The ferromagnetism and metallic conductivity of the compounds Cu[Cr2]X4, where X = S, Se or Te, have been interpreted in terms of collective “ d ” electrons on t2g symmetry from Cu2+ ions and localized d electrons of t2g symmetry at Cr3+ ions. Lotgering and van Stapele have studied the compounds CuCrRhSe4, CuCrTiS4, and M1−x Cu[Cr2]Se4, where M = Zn, Cd, or Hg. They have asserted that their results disprove this hypothesis and strongly support the existence of Cr4+ ions in the presence of Cu+ ions. It is shown that these assertions are incorrect.
Extracellular Ca2+ suppresses endotoxin-inducible tissue factor activation in monocytic THP-1 cells

BACKGROUND Monocytic tissue factor (TF), an initiator of extrinsic blood coagulation, is often activated under various inflammatory conditions including endotoxemia. This activation could be a contributing factor to the manifestation of disseminated intravascular coagulation following septic shock. HYPOTHESIS We herein determine if extracellular Ca(2+) ([Ca(2+)](ex)) regulates bacterial endotoxin (LPS)-inducible monocytic TF activation. METHODS We have employed a model monocytic cell line (THP-1) to explore the mode of action of [Ca(2+)](ex) on the modulation of LPS-induced TF activation. TF activity was measured by a single stage clotting assay, while TF expression as well as LPS recognition and its receptor expression were studied in immunofluorescent approaches. RESULTS LPS-induced TF activation was inversely correlated to [Ca(2+)](ex). Upon exposure of THP-1 cells to LPS (1.5 microg ml(-1)) for 6 h in the Hanks' medium without CaCl(2), TF was activated by nearly 10-fold. TF activation appreciably decreased with the increasing [Ca(2+)](ex). No more than 3.5-fold TF activation was detected at 5 mM [Ca(2+)](ex). Consistent with the significantly lower degree of TF activation, LPS-induced TF expression at 5 mM [Ca(2+)](ex) was 60 per cent less than that without [Ca(2+)](ex). FACScan analysis showed that LPS recognition was significantly blocked at 5 mM [Ca(2+)](ex) which however had no effect on the expression of CD14 and CD11b, the proposed major LPS receptors. Moreover, LPS binding in vitro was significantly inhibited by 5 mM CaCl(2). CONCLUSION Our results demonstrate that [Ca(2+)](ex) blocked LPS recognition without affecting its receptor expression on THP-1 monocytes. This insensitivity to LPS thereby resulted in the depressed inducible monocytic TF expression and activation.
Von Neumann Lattices of Wannier Functions for Bloch Electrons in a Magnetic Field

The problem of Bloch electrons in a magnetic field in two dimensions can be reduced to a one-dimensional problem with a Hamiltonian H that is a periodic function of x and p. Wannier functions can be defined for the sub-bands of the spectrum of this effective Hamiltonian. When the Chern class (quantized Hall conductance integer) of the sub-band is zero, the Weyl-Wigner formalism can be used to represent these Wannier functions by a von Neumann lattice. It is shown how this von Neumann lattice of Wannier functions can be defined for irrational as well as rational magnetic fields. An important benefit from using the Weyl-Wigner formalism is that symmetries of the periodic potential are reflected by symmetries of the effective Hamiltonian in phase space. It is shown how the Wannier functions can be defined so that their Wigner functions have the point symmetries of the effective Hamiltonian. An example of how these results can prove useful is given: if we take matrix elements of the Hamiltonian between the Wannier states of a sub-band, we derive a new effective Hamiltonian describing this sub-band, which is again a periodic function of coordinate and momentum operators. Since, by projecting onto a sub-band, we have also reduced the number of degrees of freedom, this operation is a renormalization group transformation. It is shown that the symmetry of the new effective Hamiltonian in phase space is the same as that of the original one. This preservation of symmetry helps to explain some unusual properties of the spectrum when the Hamiltonian has fourfold symmetry.
Algebro-geometric analogues of Donaldson's polynomials

Donaldson [5] has introduced polynomials on the second homology of any simply connected closed four-manifold, M, with b~odd (at least 3) which, up to + , are invariant under orientation preserving diffeomorphisms. For every c > Ibm+ there is a polynomial 7c(M)~ Syma(~ H2(S), where d(c) = 4c Z2(b~ + 1); to define it one considers J'/c, the set (which is in a natural way a manifold) of Gauge equivalence classes of connections on the SU(2)-bundle on M with c2 = c, antiself-dual with respect to a generic metric on M. There is a natural map /~: H2(M) ~ H2(j/c), namely slant product with 88 where P is the universal SO(3) principal bundle on M x J/c. One way of defining 7c(M) [10] is to construct a compactification of .//r Xc, carrying a fundamental class [Xc]. One proves that # extends to a map #: H2(M) ~ H2(Xc), then one defines
Effects of the intracellular Ca ion concentration upon the excitability of the muscle fiber membrane of a barnacle.

The membrane excitability and contraction were examined in single barnacle muscle fibers with different internal Ca++ concentrations by using buffer solutions made up with EGTA and Ca-gluconate in various proportions. During the passage of dc currents the membrane shows all-or-none spike potentials for internal Ca++ concentrations below about 8 x 10-8 M, oscillatory potential changes in the range between 8 x 10-8 to 5 x 10-7 M, but neither oscillatory nor spike potentials were seen for concentrations above 5 x 10-7 M. All-or-none spike potentials were suppressed when the internal Mg++ concentration exceeded 5 mM. The suppression threshold of the internal Ca++ concentration for the Sr spike is much higher than that for the Ca spike. The threshold concentration of internal Ca++ for contraction was about 8 x 10-7 M.
A Strategy for Rural Financial Market Reform: Applying the Financial Systems Approach in Ghana

We construct, using methods advocated in one strand of the Financial Systems Approach literature, a reform-and-renewal program for one of Ghana’s struggling Rural Banks--the Kaaseman Rural Bank. Questionnaire results, local informal financial practices, recent institutional innovations in Ghanaian finance, the experiences of successful “Nontraditional” rural finance institutions in developing countries, and the operating structure of the Rural Bank program indicate that this bank can implement a group-lending scheme that will reduce significantly its transaction costs and those of its customers. We thus demonstrate how the Financial Systems Approach can be employed to promote sustainable rural financial intermediation in a specific socioeconomic and institutional setting. The potential for our reform proposals to succeed in the local Ghanaian context is analyzed carefully.
Python for Development of OpenMP and CUDA Kernels for Multidimensional Data

Design of data structures for high performance computing (HPC) is one of the principal challenges facing researchers looking to utilize heterogeneous computing machinery. Heterogeneous systems derive cost, power, and speed efficiency by being composed of the appropriate hardware for the task. Yet, each type of processor requires a specific organization of the application state in order to achieve peak performance. Discovering this and refactoring the code can be a challenging and time-consuming task for the researcher, as the data structures and the computational model must be co-designed. We present a methodology that uses Python as the environment for which to explore tradeoffs in both the data structure design as well as the code executing on the computation accelerator. Our method enables multi-dimensional arrays to be used effectively in any target environment. We have chosen to focus on OpenMP and CUDA environments, thus exploring the development of optimized kernels for the two most common classes of computing hardware available today: multi-core CPU and GPU. Python's large palette of file and network access routines, its associative indexing syntax and support for common HPC environments makes it relevant for diverse hardware ranging from laptops through computing clusters to the highest performance supercomputers. Our work enables researchers to accelerate the development of their codes on the computing hardware of their choice.
REPEAT VASECTOMY REVERSAL AFTER INITIAL FAILURE: OVERALL RESULTS AND PREDICTORS FOR SUCCESS

AbstractPurpose: We review the treatment outcomes for microsurgical reconstruction following failed vasectomy reversal and identify predictors for success.Materials and Methods: We performed a retrospective review of our experience with microsurgical reconstruction in 41 men who underwent 1 or more prior unsuccessful vasectomy reversal procedures. Of these patients 20 underwent bilateral (16) or unilateral (4) vasoepididymostomy, 11 underwent bilateral (7) or unilateral (4) vasovasostomy and 10 underwent unilateral vasoepididymostomy with contralateral vasovasostomy. Postoperative followup consisted of serial semen analyses and telephone interviews.Results: Patency and pregnancy followup data were available in 33 and 31 patients, respectively. Five couples had ongoing uncorrected female factor infertility problems and were not included in pregnancy rate calculations. Mean obstructive interval was 10.6 years. Overall patency and pregnancy rates were 79 and 31%, respectively. Mean total motile sperm count f...
Postdischarge Impact of C-L Psychiatry Treatment in Obstetrical Inpatients

Purpose. Twenty-eight women, referred to C-L Psychiatry during their obstetrical inpatient stay were interviewed six months post-discharge to determine how they experienced the consultation process, whether they recollected and adhered to treatment recommendations, and whether they developed or had a recurrence of mental health problems post-discharge. Method. Semi-structured telephone interviews were conducted by a psychologist who had not been involved with patient care. Results. There was strong congruence between reason for referral as stated in psychiatric consult notes and participants' recollections and strong congruence and compliance regarding treatment recommendations. Sixty-four percent of women had concerns regarding mood post-discharge, of whom 66% sought professional help within six months. Participants' recommendations for improving the effectiveness of the C-L service to obstetrical inpatients pertained mainly to sensitivity to patients' feelings, consistency of message and personnel, and post-discharge follow-up. Conclusions. Obstetrical patients had good recollection of their experience of C-L psychiatry, and post-discharge compliance with treatment recommendations was high. A post-discharge telephone call might further enhance treatment compliance and encourage women who are struggling with mood difficulties to seek help. Contact between C-L psychiatry and patients' primary care physician may also enhance care post-discharge.
Tracking Sports Players with Context-Conditioned Motion Models

We employ hierarchical data association to track players in team sports. Player movements are often complex and highly correlated with both nearby and distant players. A single model would require many degrees of freedom to represent the full motion diversity and could be difficult to use in practice. Instead, we introduce a set of Game Context Features extracted from noisy detections to describe the current state of the match, such as how the players are spatially distributed. Our assumption is that players react to the current situation in only a finite number of ways. As a result, we are able to select an appropriate simplified affinity model for each player and time instant using a random decision forest based on current track and game context features. Our context-conditioned motion models implicitly incorporate complex inter-object correlations while remaining tractable. We demonstrate significant performance improvements over existing multi-target tracking algorithms on basketball and field hockey sequences several minutes in duration and containing 10 and 20 players respectively.
Isolation and detection of Borrelia burgdorferi DNA from cerebral spinal fluid, synovial fluid, blood, urine, and ticks using the Roche MagNA Pure system and real-time PCR

The Roche MagNA Pure automated nucleic acid extraction system was tested for its ability to extract Borrelia burgdorferi DNA from a diverse set of spiked specimen types including blood, cerebral spinal fluid, synovial fluid, urine and ticks. A method comparison between MagNA Pure automated extraction and manual extraction, using either QIAamp columns or phenol/chloroform extraction, showed equivalent detection sensitivities for all methodologies with all specimen types (except for urine, in which case QIAamp extraction was twofold less sensitive). Eighty positive clinical specimens (as determined by an independent testing method), including 76 synovial fluid, and 4 cerebral spinal fluid specimens, were found to be positive by the MagNA Pure/real-time PCR method of extraction and detection. This data shows that the MagNA Pure system can be used to extract B. burgdorferi DNA from clinical specimens, and when combined with real-time PCR, the result is an extremely sensitive assay with limited hands on time and rapid turn around times.
Phorbol ester promotes histone H3-Ser10 phosphorylation at the LDL receptor promoter in a protein kinase C-dependent manner

Histone modification is emerging as a major regulatory mechanism for modulating gene expression by altering the accessibility of transcription factors to DNA. This study unravels the relationship between histone H3 modifications and LDL receptor induction, focusing also on routes by which phosphorylation is mediated in human hepatoma HepG2 cells. We show that while histone H3 is constitutively acetylated at LDL receptor chromatin, 12-O-tetradecanoylphorbol-13-acetate (TPA) causes rapid hyperphosphorylation of histone H3 on serine 10 (histone H3-Ser10), despite global reduction in its phosphorylation levels. Ser10 hyperphosphorylation precedes LDL receptor induction and is independent of the p42/44MAPK, p38MAPK, pp90RSK, or MSK-1 cascade. Interestingly, inhibition of protein kinase C (PKC) blocks Ser10 hyperphosphorylation and also compromises LDL receptor induction by TPA. Consistent with its role, recombinant purified PKC phosphorylate purified histone H3-Ser10. Collectively, our findings highlight a novel role for PKC in regulating histone H3-Ser10 phosphorylation and suggest that histone modification provides numerous regulatory opportunities to set the overall range of control attainable for LDL receptor gene induction.
The Age Effect in Increasing Operative Mortality following Delay in Elective Abdominal Aortic Aneurysm Repair

Background Elective repair of large abdominal aortic aneurysms (AAAs) is associated with the risk of significant perioperative mortality. When abdominal aneurysm repair is delayed, patients with asymptomatic large AAAs face the risk of death from rupture. In addition to the risk of rupture, the advancing age of the patients adds a future operative risk. This risk has been historically documented in age groups. However, a more accurate representation of the increasing operative risk with age is needed. Methods We analyzed all patients in the American College of Surgeons National Surgical Quality Improvement Program database who underwent endovascular or open repair for asymptomatic infrarenal AAA between 2005 and 2012. Multivariable logistic regression was used to evaluate the effect of increasing age and operative delay on 30-day postoperative mortality. Results There were 27,576 patients who underwent AAA repair during the study period (mean age 73.5 years, standard deviation 8.6, 80% male, 24% open repair). There was a linear relative increase of 5% (odds ratio [OR] 1.05, 95% confidence interval [CI] 1.04–1.06, P Conclusions Because of increasing age, delay in surgery is associated with uniform increase in the risk of perioperative mortality in asymptomatic patients who meet criteria for AAA repair. It is important for surgeons to incorporate this more accurate estimation of operative risk into discussions with patients who qualify for treatment yet decide to forgo surgery for the repair of their AAA.
Seasonal Changes in Abundance of Host-Seeking Chiggers (Acari: Trombiculidae) and Infestations on Fence Lizards, Sceloporus undulatus

Eastern Fence Lizards (Sceloporus undulatus) in middle Tennessee are commonly parasitized by chiggers (Acari: Trombiculidae), but little is known about the ecological significance of this host-parasite system. Thus, I sampled S. undulatus and their habitats monthly to determine the seasonal pattern in chigger abundance and infestation intensity. Chigger abundance was low (mean = 1.8 chiggers) in the spring (April and May), eightfold higher throughout the summer, and declined sixfold in the fall (September and October). In general, infestation intensities on S. undulatus (males, females, and juveniles) followed the same pattern except that mean infestation intensity of males declined during the summer in spite of persistently high chigger abundance. The results of this study suggest that seasonal changes in chigger abundance are a major factor influencing infestation intensities on S. undulatus.
Point-of-care ultrasound for the evaluation of the infected pancreatic pseudocyst.

A 53-year-old man with a longstanding history of alcohol abuse presented to the Emergency Department with 3 days of worsening left upper quadrant abdominal pain, fever, and vomiting. He had noted increased left upper abdominal ‘‘swelling’’ over 1 month. The patient was febrile (38.7 C/101.7 F) and tachycardic (heart rate 112 beats/min), with otherwise normal vital signs. He had a large palpable mass in his left upper quadrant on physical examination. Laboratory assessments were significant for an elevated white blood cell count of 13,600/mm. His liver enzymes and lipase were unremarkable. A focused bedside ultrasound of the left upper quadrant was performed that identified a large heterogeneous cystic mass (Figure 1). A computed tomography (CT) scan of the abdomen with intravenous contrast revealed two large, walled-off fluid collections (Figures 2, 3).
Dose escalated, hypofractionated radiotherapy using helical tomotherapy for inoperable non-small cell lung cancer: preliminary results of a risk-stratified phase I dose escalation study.

To improve local control for inoperable non-small cell lung cancer (NSCLC), a phase I dose escalation study for locally advanced and medically inoperable patients was devised to escalate tumor dose while limiting the dose to organs at risk including the esophagus, spinal cord, and residual lung. Helical tomotherapy provided image-guided IMRT, delivered in a 5-week hypofractionated schedule to minimize the effect of accelerated repopulation.Forty-six patients judged not to be surgical candidates with Stage I-IV NSCLC were treated. Concurrent chemotherapy was not allowed. Radiotherapy was delivered via helical tomotherapy and limited to the primary site and clinically proven or suspicious nodal regions without elective nodal irradiation. Patients were placed in 1 of 5 dose bins, all treated for 25 fractions, with dose per fraction ranging from 2.28 to 3.22 Gy. The bin doses of 57 to 80.5 Gy result in 2 Gy/fraction normalized tissue dose (NTD) equivalents of 60 to 100 Gy. In each bin, the starting dose was d...
Impact of 13-Valent Pneumococcal Conjugate Vaccination on Streptococcus pneumoniae Carriage in Young Children in Massachusetts

Author(s): Lee, Grace M; Kleinman, Ken; Pelton, Stephen I; Hanage, William; Huang, Susan S; Lakoma, Matthew; Dutta-Linn, Maya; Croucher, Nicholas J; Stevenson, Abbie; Finkelstein, Jonathan A | Abstract: BackgroundIn April 2010, a 13-valent pneumococcal conjugate vaccine (PCV13) replaced PCV7 for use in the United States. We evaluated rates of pneumococcal colonization, by serotype and antibiotic resistance, in Massachusetts communities where serial cross-sectional surveillance has been conducted for the past decade.MethodsNasopharyngeal swabs were obtained from children 0 to l7 years of age and seen by primary care providers for well child or acute illness visits in 2001, 2004, 2007, 2009, and 2011. Pneumococcal isolates were serotyped by Quellung reaction and classified as PCV7 serotypes (4, 6B, 9V, 14, 18C, 19F, 23F), additional PCV13 serotypes (1, 3, 5, 6A, 7F, 19A), or non-PCV13 serotypes. Changes in colonization and impact of PCV13 were assessed using generalized linear mixed models, adjusting for known risk factors and accounting for clustering by community.ResultsIntroduction of PCV13 did not affect the rate of overall pneumococcal colonization (31% in 2011). Colonization with non-PCV13 serotypes increased between 2001 and 2011 for all children (odds ratio [OR] per year, 1.12; 95% confidence interval [CI], 1.10, 1.15; P l .0001). 19A remained the second most common serotype in 2011, although a decline from 2009 was observed. Penicillin (7%), erythromycin (28%), ceftriaxone (10%), and clindamycin (10%) nonsusceptibility were commonly identified, concentrated among a small number of serotypes (including 19A, 35B, 15B/C, and 15A). Among healthy children 6-23 months old, colonization with PCV13 serotypes was lower among recipients of PCV13 vaccine (adjusted OR, 0.30; 95% CI, 0.11, 0.78). This effect was not observed in 6- to 23-month-old children with a concomitant respiratory tract infection (adjusted OR 1.36; 95% CI, 0.66, 2.77) or children 2 to l7 years old (adjusted OR, 1.17; 95% CI, 0.58, 2.34).Conclusions13-Valent pneumococcal conjugate vaccine reduced the prevalence of colonization with PCV13 serotypes among children 6-23 months old, but its efficacy was not shown among older children.
Properties and computation of the Coulomb pair density matrix

Abstract The Coulomb pair density matrix is essential in numerical quantum mechanical studies of Coulombic systems. The properties of the pair density matrix in two and three dimensions for attractive and repulsive coulomb potentials are discussed here. These are incorporated into several listed fortran subroutines.