cssi/SciSciGPT-SciSciNet huggingface dataset:
Undesired synthetic outcomes during a project-based organic chemistry laboratory experience

While project-based chemistry laboratories are effective at providing second-year organic students with simulated research experience, there can be unexpected consequences when students carry out literature procedures. During an organic synthesis project, students accidentally added reagents for an aromatic iodination reaction in an incorrect order, resulting in the synthesis of nitrogen triiodide and the evacuation of the laboratory. A brief discussion of the events leading up to the reaction and steps taken to remediate the situation identify potential pitfalls in developing project-based chemistry laboratories.
CC-1065 und die Duocarmycine: mechanistische Studien zum Verständnis ihrer biologischen Funktion†

Wir fassen hier Arbeiten zusammen, die sich mit den DNA-Alkylierungs-Eigenschaften einer Klasse wirksamer Cytostatica/Antibiotica, zu denen CC–1065 und die Duocarmycine zahlen, befasten, sowie Untersuchungen, die fur diese Verbindungen die elementaren Zusammenhange zwischen Struktur, funktioneller Reaktivitat und biologischem Verhalten ermittelten. Neben dem Studium der Naturstoffe selbst haben Untersuchungen mit strukturell stark veranderten, synthetischen Substraten und den nicht in der Natur vorkommenden („nichtnaturlichen”) Enantiomeren der Naturstoffe und verwandter Analoga dazu beigetragen, die strukturelle Grundlage fur die sequenzselektive Alkylierung von Duplex-DNA zu bestimmen, und den Schlussel zum Verstandnis der elementaren Zusammenhange zwischen chemischer Struktur, funktioneller Reaktivitat und biologischem Verhalten geliefert. Die charakteristische DNA-Alkylierung erfolgt durch reversible, stereoelektronisch gesteuerte Adenin-N3-Addition an das am wenigsten substituierte Kohlenstoffatom des aktivierten Antibioticum-Cyclopropanrings innerhalb AT-reicher Bindungsstellen in der kleinen Furche. Sowohl die naturlichen als auch die nichtnaturlichen Enantiomere alkylieren DNA, und in beiden Fallen wird die Sequenzselektivitat durch die bevorzugte nichtkovalente Bindung der Substrate an AT-reiche Regionen innerhalb der schmaleren und tieferen kleinen Furche und durch die Zuganglichkeit der Alkylierungsstelle beim Eindringen in diese Furche gesteuert und dominiert. Unter den elementaren Beziehungen zwischen Struktur und Eigenschaften fallt besonders der direkte Zusammenhang zwischen chemischer oder funktioneller Stabilitat und biologischer Wirksamkeit auf. In kurzer Zeit wurden vereinfachte, auf Naturstoff-Leitbildern basierende und leicht zugangliche synthetische Substrate mit einer vergleichbaren und ausergewohnlichen biologischen Wirksamkeit (IC50 = 1–50 pM) und einer verbesserten Wirkung entwickelt. Die bisher definierten elementaren Zusammenhange konnten den Grundstein fur kunftige Entwicklungen und Fortschritte legen.
Three electrostatic temperature drift instabilities

This paper considers temperature drift instabilities, modes which can be driven unstable solely by a temperature gradient perpendicular to a magnetic field. The linear electrostatic dispersion relation for a Vlasov plasma in a uniform magnetic field is used and propagation is assumed to be in the plane perpendicular to the gradient. Three temperature drift instabilities have been found. The ion temperature drift instability arises at frequencies much below the ion cyclotron frequency, the electron temperature drift instability propagates somewhat below that frequency and the lower-hybrid temperature drift instability has frequencies above the lower-hybrid frequency. The first of these modes is driven by an ion temperature gradient and is enhanced by increasing T e / T i . The latter two modes are driven by an electron temperature gradient and are enhanced by a decreasing T e / T i . Density gradients are considered as an additional source of free energy, and comparisons of temperature drift with density drift instabilities are made.
Design methodology for robust stabilizing controllers

This paper considers the problem of designing control laws for linear systems with time-varying uncertainty. A method for determining a linear feedback control which stabilizes the system for all possible uncertainty is presented. This control is robust in the sense that it guarantees asymptotic stability regardless of the disturbance. The results are applied to several aircraft examples .
Vanishing Polymorphism of (2E)-2-Cyano-3-[4-(Diethylamino)phenyl]prop-2-enethioamide: X-ray Structural Study and Polymorph Prediction

Synthesis and crystallization of a polar organic compound (2E)-2-cyano-3-[4-(diethylamino)phenyl]prop-2-enethioamide (CDPE) gave two new crystalline polymorphs (1 and 2) and an acetonitrile solvate (pseudopolymorph, 3) of this compound. The third crystalline polymorph of CDPE (4) was described in the literature earlier. It was found that in crystalline polymorphs 1, 2, and 4 molecules adopt three different conformations. Experimental observations show that polymorph 1 is a predominant form of the CDPE compound, while all other crystalline forms we were unable to reproduce under different conditions. Quantum ab initio calculations of relative conformational energies of molecules found in these polymorphs revealed that the conformer in polymorph 1 has significantly lower energy than conformers in polymorphs 2 and 4. This fact explains the predominant formation of polymorph 1 under different experimental conditions. The polarity of CDPE molecules and distinctions in their molecular and crystal structures mak...
Progesterone regulation of primordial follicle assembly in bovine fetal ovaries

Fertility in mammals is dependant on females having an adequate primordial follicle pool to supply oocytes for fertilization. The formation of primordial follicles is called ovarian follicular assembly. In rats and mice progesterone and estradiol have been shown to inhibit follicle assembly with assembly occurring after birth when the pups are removed from the high-steroid maternal environment. In contrast, primordial follicle assembly in other species, such as cattle and humans, occurs during fetal development before birth. The objective of the current study is to determine if progesterone levels regulate primordial follicle assembly in fetal bovine ovaries. Ovaries and blood were collected from bovine fetuses. Interestingly, ovarian progesterone and estradiol concentrations were found to decrease with increasing fetal age and correlated to increased primordial follicle assembly. Microarray analysis of fetal ovary RNA suggests that progesterone membrane receptor and estrogen nuclear receptor are expressed. Treatment of fetal bovine ovary cultures with a higher progesterone concentration significantly decreased primordial follicle assembly. Observations indicate that progesterone affects ovarian primordial follicle assembly in cattle, as it does in rats and mice.
Calcium Signaling Inside Cilia Upon Mechanical Bending

The primary cilium is a sensory organelle central to many signaling pathways. Direct visualization of signaling dynamics within primary cilia constitutes a major technical challenge due to the sub-micron dimensions of the organelle as well as its close proximity to the cell body. By newly designing and developing a genetically encoded calcium indicator (GECI) targeted to primary cilia without compromising indicator efficiency, we now demonstrate the unprecedented capability to visualize Ca2+ dynamics within the ciliary lumen with high specificity, sensitivity and wide dynamic range. Simultaneous dual-color Ca2+ imaging at cytosol and primary cilia revealed highly resolved propagation of Ca2+ from the cytosol into distal tip of primary cilia in response to ATP. In addition, we provide direct evidence of dynamic Ca2+ signaling within primary cilia immediately after cilia bending caused by a mechanical flow. Therefore, the cilia-targeted GECI serves as a powerful tool to elucidating the roles of Ca2+ signaling in regulating sensory functions of primary cilia. The present approach is readily generalized to other signaling molecules and to other sub-micron cellular compartments.(Reference: Su S. et al., Nature Methods, Accepted on 8/13/13, 10.1038/nmeth.2647).
Optimal p-cyclic SOR for complex spectra

Abstract We consider the successive overrelaxation (SOR) method for the solution of a linear system Ax = b, when the matrix A has a block p × p partitioned p-cyclic form and its associated block Jacobi matrix Jp is weakly cyclic of index p. Following the pioneering work by Young and Varga in the 1950s, many researchers have considered various cases for the spectrum σ(Jp) and have determined (optimal) values for the relaxation factor ω ϵ (0,2) so that the SOR method converges as fast as possible. After the most recent work on the best block p-cyclic repartitioning and that on the solution of large-scale systems arising in queueing network problems in Markov analysis, the optimization of the convergence of the p-cyclic SOR for more complex spectra σ(Jp) has become more demanding. Here we state the one-point problem for the general p-cyclic complex SOR case. The existence and the uniqueness of its solution are established by analyzing and developing further the theory of the associated hypocycloidal curves. For the determination of the optimal parameter(s) an algorithm is presented and a number of illustrative numerical examples are given.
Molecular imaging with single photon emission computed tomography

With the emergence of the new field of molecular imaging, there is an increasing demand for the development of sensitive and safe novel imaging agents that can be rapidly translated from small animal models into patients. Nuclear medicine techniques have the ability to detect and serially monitor a variety of biologic and pathophysiologic processes, usually with tracer quantities of radiolabeled peptides, drugs, and other molecules at doses free of pharmacologic side effects, unlike the current generation of intravenous agents required for magnetic resonance (MR) and computed tomography (CT) scanning. The focus of this article will be to review the novel molecular imaging-based contrast agents that have the greatest potential for use as radiopharmaceuticals for single photon emission computed tomography (SPECT) imaging. We will discuss how these new tracers - particularly when coupled to CT or magnetic resonance imaging (MRI) - can be employed in the noninvasive study of a number of human diseases in the nuclear medicine clinic in near the future.
Diagnosis and treatment of sudden-onset sensorineural hearing loss: a study of 51 patients.

Abstract Objective: The study purpose was to determine the efficacy of steroid and antiviral therapy in the management of idiopathic sudden sensorineural hearing loss (SSNHL). Study Design and Setting: We conducted a retrospective study of patients presenting to an academic tertiary care center. Fifty-one patients were evaluated. All patients were placed on the same treatment protocol. Results: Thirty-seven patients (73%) had recovery of hearing. Ninety-one percent of patients with vertigo and all patients with mid-frequency hearing loss and up-sloping hearing loss recovered with treatment (P
A myeloproliferative neoplasm with translocation t(8;9)(p22;p24) involving JAK2 gene.

![Figure][1] A 35-year-old male presented with a several-weeks history of abdominal discomfort, early satiety, low-grade fever, night sweats, and weight loss. Physical examination revealed pale skin and a massive hepatosplenomegaly. A complete blood count showed severe anemia,
Theory-driven behavioral intervention research for the control of diarrheal diseases.

Abstract Essentially all methods to reduce diarrheal morbidity and mortality require behavioral change. Research is required to design, implement and evaluate behavior-modifying interventions. Accumulated experience in the many involved disciplines should serve as a basis for this research. However, each of these disciplines is associated with different research perspectives and analytic assumptions; thus integration of these varied but potentially complementary experiences has been elusive. In the present paper, arguing that such perspectives and assumptions are embodied in discipline-based theory, we have developed a generic framework for the conduct of theory-based behavioral intervention research. We illustrate the application of this framework through two vignettes applying two of the theories and models to the development of hypothetical handwashing interventions.
Elastic electron scattering cross sections for molecular hydrogen.

Using an electron-beam - molecular-beam apparatus and employing the relative flow technique, ratios of the differential elastic scattering cross sections (DCSs of H2 to He were measured at incident electron energies of 15-100 eV and over the angular range of 10-125 degrees. From these ratios, the absolute elastic DCSs for H2 were determined by normalization to accurate, available elastic DCSs of He. Since pure rotational structure was not resolved in this work, the DCSs reported are the sum of elastic and rotational excitations of H2 at room temperature. The reliability of the relative flow normalization to He was checked at each energy and angle by performing similar elastic DCS measurements on Ne (for which the cross sections are known). The resulting absolute Ne DCSs were found to be in good agreement (within 10 percent with the Ne elastic DCSs measured previously (Register and Trajmar, 1984). From the DCSs, integral and momentumtransfer cross sections were calculated. The present results are compared with other recent measurements.
Qualifying for the license to replicate.

Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco,California 94143-0448A single replication fork would take more than a year to replicate the genome of Xenopus. Bydividing the task among many thousands of replicons, each replicated by forks emanating fromindividual origins, replication is instead completed in as little as 30 min. While this efficientstrategy has been adopted by all eukaryotes, it introduces a complication. To maintain theintegrity of the genome, multiple replicons must now be coordinated so that all sequences arereplicated exactly once per cell cycle. Because different replicons are often replicated atdifferent times during S phase, replicated regions must be distinguishable from unreplicatedregions to avoid problems of rereplication. We suggest that this distinction is based upon afundamental feature of replication initiation.Two things happen at origins of replication: proteins are recruited to origins to assemblemultiprotein replication machines (Figure 1, left), and these assemblies are triggered to initiatereplication forks (Figure 1, right). Replication components accompany the departing forks,leaving behind a spent origin. Consequently, reinitiation should require assembly of newcomponents at the origin. If this assembly is restricted to one part of the cell cycle and theinitiation of forks to another, then origin firing would occur only once per cell cycle (Figure1).The transition between replication-competent and replication-incompetent phases of the cellcycle has been explored in a series of early and influential cell fusion experiments (Rao andJohnson, 1970). Upon fusion with an S phase cell, nuclei from G1 cells, but not from G2 cells,replicate their DNA. Thus, even when present in cytoplasm capable of supporting S phase, theG2 nucleus is incompetent to replicate. Since G2 nuclei are converted into G1 nuclei by thepassage through mitosis, mitosis must provide replication competence to the G2 nucleus. Inthe last several years, in vitro experiments using Xenopus egg extracts as well as geneticexperiments using fission yeast have given rise to two rather different models for the basis ofthis mitotic transition. We outline each of these areas of research below and evaluate featuresof each model in an attempt to bring us closer to a unified understanding of these events.
TEACHING NAMING OF COIN VALUES—COMPREHENSION BEFORE PRODUCTION VERSUS PRODUCTION ALONE1

The purposes of this experiment were to determine whether (a) it would require fewer trials to teach verbal production of coin values directly or to teach auditory comprehension first, (b) comprehension training would generalize or transfer to production, and (c) production training would generalize to comprehension. Fourteen mentally retarded subjects participated. Their mean mental age was 4.83 yr (SD = 1.83), their mean chronological age was 12.67 yr (SD = 3.17), their mean IQ was 43.86 (SD = 7.81), and their mean arithmetic grade level was Kindergarten 0.1. A matched groups pretest-posttest design, as well as a multiple baseline across responses within each group were employed. The Comprehension-Production Group received coin-value training using two procedures sequentially: auditory comprehension (pointing to the correct coins in response to their verbally stated value) followed by verbal production (verbally stating the coins' value in response to a pointing prompt). The Production Group was trained on the production procedure only. Each subject was repeatedly administered coin-value comprehension and coin-value production tests, which provided the dependent measures. The results indicated that the two experimental groups improved significantly in their comprehension and production of coin values from pretest to posttest and maintained those increments on one- and four-week followup tests. Mean group performance on four-week followups ranged from 89 to 96% correct for the two dependent measures and two groups. Multiple-baseline data showed pronounced increases in performance only after training was initiated on a particular coin. A comparison of the number of trials required for both groups to complete their respective training programs indicated that teaching production alone (X trials = 137.42) was significantly more efficient than training both comprehension and production (X = 281.71). The failure of the comprehension procedure to facilitate production acquisition was evidenced by the fact that the Comprehension-Production Group required as many verbal naming trials to achieve mastery as did the Production Group. On the other hand, there was generalization from production training to comprehension. Subjects in the Production Group who were not trained to point to the coins in response to verbal instruction averaged 99% correct on the comprehension test. Research to this point may suggest an interaction between mental level and direction of transfer. The mentally retarded may experience facilitation from production to comprehension training, and for the nonretarded, the direction of transfer may be the converse.
Sensory and Motor Neuron-derived Factor Is a Transmembrane Heregulin That Is Expressed on the Plasma Membrane with the Active Domain Exposed to the Extracellular Environment

The β-heregulin sensory and motor neuron-derived factor (SMDF) has been suggested to be an important regulator of Schwann cell development and proliferation. In the present study, human SMDF was expressed in cultured cell lines. The cells and the recombinant protein were used to examine the membrane association and biological activity of the growth factor. Transfection of cells with SMDF cDNA constructs bearing FLAG epitope tags at either the amino- or carboxyl-terminal ends of the polypeptide resulted in expression of anti-FLAG immunoreactive polypeptides of approximately 44 and 83 kDa. The 83-kDa polypeptide was the major form expressed on the cell surface, as demonstrated by sensitivity to proteolysis in intact cells and surface biotinylation. SMDF was tightly associated with membranes isolated from transfected cells but was solubilized by Triton X-100. Immunofluorescent staining and immunoprecipitation experiments using cells expressing amino- or carboxyl-terminal tagged SMDF revealed that only the carboxyl-terminal end of the protein is exposed on the cell surface. Membranes from SMDF-transfected cells stimulated tyrosine phosphorylation of the β-heregulin receptor ErbB3 in Schwann cells. Conditioned medium from transfected cells contained a similar activity, suggesting that SMDF is subject to proteolytic release from the plasma membrane. In contrast with other β-heregulin isoforms, SMDF failed to bind heparin. Stimulation of Schwann cell ErbB3 receptor phosphorylation by SMDF was not affected by inhibition of Schwann cell heparan sulfate proteoglycan synthesis. These results demonstrate that SMDF is a type II transmembrane protein. This orientation places the active epidermal growth factor homology domain, which is located near the carboxyl-terminal end of the polypeptide, on the cell surface, where it can function as a membrane-anchored growth factor.
Fabrication Technologies for Advanced Heat Transfer Applications

Microchannel devices with channel widths in the range from one micron to several hundred microns have become increasingly important structures for heat transfer applications. This paper will examine several classes of fabrication technologies that are employed in the field. Established technologies, such as bulk and surface micromachining, high aspect ratio machining, and conventional machining have been perfected over the last several decades and are the principal methods of creating microchannel structures. Synthesizing technologies, such as wafer bonding and micromolding techniques, allow these primary structures to be assembled together into working devices or enable high volume, low cost manufacturing using microstructured masters. Established and synthesizing technologies have reached a high level of performance and are generally the subject of refinement efforts rather than innovative investigations. Active research into new materials, processes, and fabrication strategies are found in the class of emerging technologies. This paper will briefly review the dimensional spectrum of microchannels and survey the established and synthesizing technologies. Then an exploration of emerging technologies will be made. The topic of rapid prototyping will be given particular emphasis.Copyright © 2003 by ASME
Astrophysical Constraints on the Gravitational Constant

We study the astrophysical bounds on the change of the gravitational constant with time. We found that |Ġ/G|<10−12yr−1 is the condition that has to be satisfied in order not to cause a conflict with the observations. We find the condition to be in accord with the lower limits, the superstring theory predicts.
Mössbauer Study of Dy3+ in CaF2

The Mossbauer electric quadrupole interaction for Dy3+ in both oxygen-free and oxygen-injected CaF2 is measured between 90 and 630 K. Comparison of the experimental data with theoretical calculations confirms that in oxygen-free CaF2 the stabilization occurs via an interstitial F− ion, while oxygen injection leads to stabilization by oxygen substitutionally replacing F− ions. Es wird die elektrische Mosbauer-Quadrupolwechselwirkung fur Dy3+ in Sauerstoff-freiem und Sauerstoff-dotiertem CaF2 im Temperaturbereich 90 bis 630 K gemessen. Ein Vergleich der experimentellen Daten mit theoretischen Berechnungen zeigt, das im Sauerstoff-freien CaF2 die Stabilisierung durch ein Zwischengitter-F−-Ion stattfindet, wahrend Sauerstoffdotierung zu Stabilisierung durch Ersetzen von F−-Ionen durch Sauerstoffionen fuhrt.
Combined television viewing and computer use and mortality from all-causes and diseases of the circulatory system among adults in the United States

Watching television and using a computer are increasingly common sedentary behaviors. Whether or not prolonged screen time increases the risk for mortality remains uncertain. Mortality for 7,350 adults aged ≥ 20 years who participated in the National Health and Nutrition Examination Survey during 1999-2002 and were followed through 2006 was examined. Participants were asked a single question about the amount of time they spent watching television or videos or using a computer during the past 30 days. During a median follow-up of 5.8 years, 542 participants died. At baseline, 12.7% of participants reported watching television or using a computer less than 1 h per day, 16.4% did so for 1 h, 27.8% for 2 h, 18.7% for 3 h, 10.9% for 4 h, and 13.5% for 5 or more h. After extensive adjustment, the hazard ratio for all-cause mortality for the top category of exposure was 1.30 (95% confidence interval: 0.82, 2.05). No significant trend across categories of exposure was noted. The amount of screen time was also not significantly related to mortality from diseases of the circulatory system. In the present study, screen time did not significantly predict mortality from all-causes and diseases of the circulatory system.
Hydraulic characteristics of wire-wrapped rod bundles

Abstract Existing hydraulic data such as pressure fields, velocity fields, friction factors, flow split and sweeping flows were reviewed and summarized. In addition equations were suggested to calculate subchannel friction factors, flow split and flow sweeping. It was concluded that sufficient data and analysis exist to generate a complete physical model to characterize turbulent flow in wire-wrapped rod bundles; there are inadequate data to construct a physical model to describe laminar and natural circulation flow. Potential hydraulic problems related to rod bundle dimensional tolerances, non-nominal and/or time-dependent pressure drop characteristics should be resolved.
A Capacity-Based Approach to Receiver Sensitivity for Atmospheric Lasercom Systems

We present an approach to analyzing receiver sensitivity in a fading channel that is rooted in capacity analysis. The approach supports rapid design trades during the early stages of system design.
Toxicokinetics of Intravenous Methanol in the Female Rat

Toxicokinetics of Intravenous Methanol in the Female Rat. Pollack, G. M., Brouwer, K. L. R., and Kawagoe, J. L. (1993). Fundam. Appl. Toxicol. 21, 105-110. The toxicokinetics of intravenously administered methanol were examined in female Sprague-Dawley rats. Animals received a single administration of 100, 500, or 2500 mg methanol/kg; the two lower doses were administered as a bolus, while the high dose was administered over 1.5 min. A small (approximately 3%) but statistically insignificant (p > 0.1) degree of transpulmonary methanol extraction, expressed as the fractional arterial-venous difference in concentration, was observed after administration of 250 mg methanol/kg. The elimination of methanol from the systemic circulation was markedly nonlinear, suggestive of a significant capacity-limited route of elimination. A single set of kinetic parameters (apparent distributional volume of the central compartment [Vc], intercompartmental transfer rate constants [k12 and k21], and Vmax and Km for elimination) described the blood methanol concentration-time data from rats receiving the 100 and 500 mg/kg doses. Blood methanol concentrations declined much more rapidly in animals receiving the 2500 mg/kg dose than would be predicted from the kinetic parameters derived from the other two experimental groups. The data from the 2500 mg/kg group could be described adequately by a kinetic model incorporating parallel first-order and saturable elimination processes. A portion of this apparent linear elimination pathway was due to renal excretion of the unchanged alcohol. The presence of both linear and nonlinear elimination pathways for methanol may have implications regarding high-dose to low-dose toxicologic extrapolations.
Children's interpretations of general quantifiers, specific quantifiers and generics

Recently, several scholars have hypothesised that generics are a default mode of generalisation, and thus that young children may at first treat quantifiers as if they were generic in meaning. To address this issue, the present experiment provides the first in-depth, controlled examination of the interpretation of generics compared to both general quantifiers (‘all Xs’, ‘some Xs’) and specific quantifiers (‘all of these Xs’, ‘some of these Xs’). We provided children (3 and 5 years) and adults with explicit frequency information regarding properties of novel categories, to chart when ‘some’, ‘all’ and generics are deemed appropriate. The data reveal three main findings. First, even 3-year-olds distinguish generics from quantifiers. Second, when children make errors, they tend to be in the direction of treating quantifiers like generics. Third, children were more accurate when interpreting specific versus general quantifiers. We interpret these data as providing evidence for the position that generics are a...
Adaptive growth changes of the gonial region in Macaca mulatta

An experimental study of functional and adaptive growth changes of the gonial region associated with removal of all anterior teeth is being carried out through the life span of the Macaca mulatta monkeys. Radiographic cephalometry, using metallic implants as consistent points of reference and histological methods using in vivo tetracycline bone labeling, are the principal experimental techniques in the study. The present paper covers the results obtained from the longitudinal observations of the infant group from two to 24 months of age. The angular measurements of the gonial angle, linear measurements of the horizontal and vertical rates of growth in the gonial region were made in experimental and control groups. The data obtained from the angular measurements showed negative regression trends in both groups. The data from linear measurements of horizontal and vertical rate of growth exhibited positive linear regression trends with age. The histological findings, however, indicate differences between the two groups. Sections from the control group show some bone apposition in the gonial region, while experimental animals show extensive resorption. The results of this study show the inadequacy of standard anthropometric methods in the determination of adaptive growth changes of the gonial region at that early age.
Electromagnetically induced transparency with two dimensional electron spins

Abstract The electronic spin degrees of freedom in semiconductors have coherence times that are several orders of magnitude longer than other relevant timescales. We show that application of a pair of laser fields, whose frequencies differ by the Zeeman splitting, gives rise to electromagnetically induced transparency in an optically dense two-dimensional electron gas under high magnetic fields. Even though reduction in group velocity and enhancement of photon-photon interaction is largest for filling factor ν =1, the effect should be observable for any 1≤ ν
Radiologic-pathologic conference of Children's Hospital Boston: abdominal mass in a prepubertal girl.

A 9-year old girl with a large abdominal mass is presented. The clinical history, CT images, histological dindings, current classification and therapy are discussed.
Notes: Disease-Associated Blood Changes and Normal Seasonal Hematological Variation in Winter Flounder in the Hudson–Raritan Estuary

Abstract Hematological variables of diseased and apparently healthy winter flounder Pleuronectes americanus were evaluated during fin rot epizootics in the Hudson–Raritan estuary, New York–New Jersey. Most diseased fish had significantly lower (average, 43% lower; P < 0.05) levels of hemoglobin, erythrocytes, hematocrit, and plasma protein than healthy fish; blood deficiencies were more frequent among juveniles (ages 1 and 2) than adults. The results indicate that the disease had severe consequences for this species. Normal seasonal variation in winter flounder hematology was determined by assessment of healthy fish through an annual cycle, Hemoglobin, erythrocyte, and hematocrit values were high between October and April–May and low between June and September. Plasma protein levels were high in June–December (January data were not obtained), and low in February–May. Juveniles and adults differed significantly in levels of plasma protein through the annual cycle. Temporary (1–7-month) differences in hemog...
Kinetics of the water-gas shift reaction over several alkane activation and water-gas shift catalysts

Abstract The water-gas shift reaction (WGS) over three commercial WGS catalysts and four oxide catalysts used for alkane activation has been studied at atmospheric pressure and in the temperature range of 160 to 600 °C. The oxide catalysts used were two ethane oxydehydrogenation catalysts, namely Mo 19 V 5 Nb 1 O x and V 5 Nb 1 O x , and two methane coupling catalysts, namely Ca 3 NiK 0.05 O x and LiMgO x . The commercial water-gas shift catalysts used were two Fe 3 O 4 -Cr 2 O 3 catalysts and one CuZnO/Al 2 O 3 catalyst. All catalysts except the ethane oxidehydrogenation catalysts and LiMgO x showed high activity for the water-gas shift reaction below 400°C. It is evident that Fe, Cr, Zn, Cu and Ni oxides or metals enhance the water-gas shift reaction. The commercial CuZnO/Al 2 O 3 catalyst was the most active WGS catalyst per gram of the catalyst at 160–250°C, whereas the Fe 3 O 4 -Cr 2 O 3 ) catalysts showed high activity above 300 °C. The specific rates of Ca 3 NiK 0.05 O x , and LiMgO x were, however, higher than the specific rates of the commercial catalysts. The apparent activation energies for the conversion of carbon monoxide to carbon dioxide were 53 kJ/mol for CuZnO/Al 2 O 3 , 68 kJ/mol for LiMgO x , 86 kJ/mol for Ca 3 NiK 0.05 O x , 95 kJ/mol and 110 kJ/mol for the Fe 3 O 4 -Cr 2 O 3 catalysts, 101 kJ/mol for Mo 19 V 5 Nb 1 O x , and 132 kJ/mol for V 5 Nb 1 O x . For the commercial catalysts, the power-law rate model with concentration exponents of carbon monoxide and water close to one and zero, respectively, gave the best results. For V 5 Nb 1 O x , and Ca 3 NiK 0.05 O x , the concentration exponents of carbon monoxide and water close to 0.5 fit the results best. For Mo 19 V 5 Nb 1 O x , the reaction was first order in carbon monoxide concentration whereas for LiMgO x , it was zero order in carbon monoxide concentration and 0.5 order in water concentration. Ca 3 NiK 0.05 O x and LiMgO x were active for the water-gas shift reaction in the temperature range of oxidative methane coupling. Thus, it is probable that the water-gas shift reaction can occur during methane coupling when these catalysts are used. The water-gas shift reaction is, however, unlikely to occur during the oxidative dehydrogenation of ethane since the conversions of carbon monoxide to carbon dioxide were very low at 350–500°C.
Linearly constrained minimum variance beamforming with quadratic pattern constraints for spatially spread sources

Antenna arrays that receive emissions from spatially spread sources require beamformers with wider beamwidths than point source beamformers. The framework of linearly constrained minimum variance beamforming with quadratic pattern constraints (LCMV-QPC) is used to develop beamformers with a specified main beamwidth and sidelobe levels. The problem is formulated by imposing a set of inequality constraints on the mean-square error between the achievable beampattern and an ideal beampattern over a set of angular regions. The technique is used to synthesize quiescent beamformers with the desired beampattern characteristics for circular and cylindrical arrays.
Spectra and structure of organophosphorus compounds. XLVIII—Raman and infrared spectra, conformational stability, vibrational assignments and ab initio calculations of dimethyl(methylthio)phosphine

The Raman spectra (3200–10 cm−1) and infrared spectra (3200–50 cm−1) of dimethyl(methylthio)phosphine, CH3SP(CH3)2, and dimethyl(methyl-d3-thio)phosphine, CD3SP(CH3)2, in the gas and solid forms were recorded. Additionally, the Raman spectra of the liquids were recorded and qualitative depolarization ratios measured. All 36 of the normal modes were assigned and the asymmetric torsion was observed in the far-infrared spectrum of gaseous CH3SP(CH3)2 at 75 cm−1. From a comparison of the vibrational spectra obtained for the fluid phases with those obtained for the amorphous and annealed solids, it is concluded that the molecule exists as a mixture of the cis and trans conformers in the fluid phases with the trans conformer being the more stable form in the liquid and the only one present in the spectra of the annealed solid. However, for the vapor state the cis conformer is the more stable form. The enthalpy difference between the cis and the trans conformers was determined from a variable-temperature study of the Raman spectrum of the liquid to be 199 ± 8 cm−1 (569 ± 23 cal mol−1). A complete vibrational assignment is proposed which is supported by a normal coordinate calculation obtained from the force fields calculated with the ab initio RHF/3–21G* basis set. Full geometry optimizations were carried out with the 3–21G* and 6–31G* basis sets for the transition state to determine the barriers to internal rotation about the CH3SP bond. All of these results are compared with corresponding data for several other organophosphorus compounds.
Enhanced cardiac fatty acid utilization induced by high dietary fat: a potential regulatory role for mitochondrial aconitase

Background Obesity is an independent risk factor for cardiovascular disease and Type 2 diabetes, a condition that enhances the risk for various cardiomyopathies. Obesity is known to induce a state of metabolic inflexibility within the heart characterized by increased mitochondrial reliance on fatty acids for energy production. While the molecular mechanisms are not fully clarified, these changes in metabolism are thought to contribute to degeneration of cardiovascular function. The focus of my research is to investigate regulatory mechanisms that control dietinduced changes in fatty acid utilization (b-oxidation) by cardiac mitochondria.
Managing the long tail of science: data and communities

We describe the origins of the long tail of data, and discuss the form it takes for scientific and scholarly data. This has implications and opportunities for managing the long tail that are articulated as a set of questions posed as a starting point for discussions by a panel at XSEDE 2012.
Community Connections: Linking Primary Care Patients to Local Resources for Better Management of Obesity

Community Connections: Linking Primary Care Patients to Local Resources for Better Management of Obesity is a toolkit based on research conducted by the State Networks of Colorado Ambulatory Practi...
The Use of Morphologic and Molecular Techniques to Estimate Genetic Variability and Relationships of Small Populations

The character of systematic and population studies has been greatly changed by recent advances in techniques of morphologic and molecular analysis. However, such techniques have not been widely applied to the immediate problems involving the conservation of rare and endangered species. We outline some specific questions relevant to conservation biologists that can be addressed by morphologic and molecular analyses and provide a brief explanation of each analysis and some of their weaknesses. Finally, examples are provided from our research on canids that illustrate the application of morphologic and molecular genetic techniques to conservation problems.
Control of Pierce's Disease by Phage.

Pierce’s Disease (PD) of grapevines, caused by Xylella fastidiosa subsp. fastidiosa (Xf), is a limiting factor in the cultivation of grapevines in the US. There are presently no effective control methods to prevent or treat PD. The therapeutic and prophylactic efficacy of a phage cocktail composed of four virulent (lytic) phages was evaluated for control of PD. Xf levels in grapevines were significantly reduced in therapeutically or prophylactically treated grapevines. PD symptoms ceased to progress one week post-therapeutic treatment and symptoms were not observed in prophylactically treated grapevines. Cocktail phage levels increased in grapevines in the presence of the host. No in planta phage-resistant Xf isolates were obtained. Moreover, Xf mutants selected for phage resistance in vitro did not cause PD symptoms. Our results indicate that phages have great potential for biocontrol of PD and other economically important diseases caused by Xylella.
The Tip-Link Antigen, a Protein Associated with the Transduction Complex of Sensory Hair Cells, Is Protocadherin-15

Sound and acceleration are detected by hair bundles, mechanosensory structures located at the apical pole of hair cells in the inner ear. The different elements of the hair bundle, the stereocilia and a kinocilium, are interconnected by a variety of link types. One of these links, the tip link, connects the top of a shorter stereocilium with the lateral membrane of an adjacent taller stereocilium and may gate the mechanotransducer channel of the hair cell. Mass spectrometric and Western blot analyses identify the tip-link antigen, a hitherto unidentified antigen specifically associated with the tip and kinocilial links of sensory hair bundles in the inner ear and the ciliary calyx of photoreceptors in the eye, as an avian ortholog of human protocadherin-15, a product of the gene for the deaf/blindness Usher syndrome type 1F/DFNB23 locus. Multiple protocadherin-15 transcripts are shown to be expressed in the mouse inner ear, and these define four major isoform classes, two with entirely novel, previously unidentified cytoplasmic domains. Antibodies to the three cytoplasmic domain-containing isoform classes reveal that each has a different spatiotemporal expression pattern in the developing and mature inner ear. Two isoforms are distributed in a manner compatible for association with the tip-link complex. An isoform located at the tips of stereocilia is sensitive to calcium chelation and proteolysis with subtilisin and reappears at the tips of stereocilia as transduction recovers after the removal of calcium chelators. Protocadherin-15 is therefore associated with the tip-link complex and may be an integral component of this structure and/or required for its formation.
Interpreting the views in an engineering drawing

A method is presented for identifying the views in an engineering drawing along with their associated view points in preparation for 3D interpretation of the object shape. A formal procedure is developed for constructing a set of view-based coordinate systems that act as intermediate 2.5D coordinates to relate the 2D drawing-based coordinates to the 3D object-based coordinates. The method can accommodate auxiliary views in addition to the standard orthogonal set, and the number of views and their layout in the drawing need not be known a priori. Moderate errors in line placement and view alignment can also be accommodated. >
A sensitivity study of radiative-convective equilibrium in the tropics with a convection-resolving model

Statistical-equilibrium (SE) states of radiative‐convective systems in tropical oceanic conditions are simulated with a cloud ensemble model (CEM) in this study. Typical large-scale conditions from the Marshall Islands and the eastern tropical Atlantic regions are used to drive the CEM. The simulated SE precipitable water, column temperature, and relative humidity are only slightly higher than those of the observed mean states in both regions when time-invariant large-scale total advective cooling and moistening effects are imposed from observations. They are much higher than the observed if time-invariant observed large-scale ascent is imposed for the Marshall Islands region (i.e., ignoring horizontal advective effects). Compared with results from two similar studies, this SE state is somewhere between the cold/dry regime by Sui et al. and the warm/humid regime by Grabowski et al. Temporal variations of the imposed large-scale vertical motion that allows for subsidence make the SE state colder and drier. It remains about the same, however, if the magnitude of the imposed large-scale vertical motion is halved. The SE state is also colder and drier if solar radiation is absent. In general, all the SE states show that wet columns are thermally more stable (unstable) and dry columns are thermally more unstable (stable) in the lower (upper) troposphere. Column budget analyses are performed to explore the differences among the simulations performed in this study and among the different studies.
Coordinate expression of c-fos and jun B is induced in the rat striatum by cocaine.

In cells in culture, specific stimuli induce selective patterns of immediate-early gene induction. In the present study, we tested for such selectivity of stimulated gene expression by monitoring the expression of fos/jun gene mRNAs in the striatum in rats treated in vivo with the indirect dopamine agonist cocaine. We found by Northern blot and in situ hybridization analysis that cocaine induces the coordinate expression of c-fos and jun B mRNAs in neurons of the rat's striatum. By contrast, another immediate-early gene of the leucine- zipper family, c-jun, was not induced in striatal neurons by cocaine at any time tested from 1 to 24 hr after treatment. With the same probe, we could detect the induction of c-jun mRNA (as well as that of c-fos and jun B mRNAs) in the hippocampus following administration of pentylenetetrazol. The induction of expression of c-fos and jun B was rapid and transient, with peak expression occurring at approximately 1 hr after cocaine administration, and the induction of the two genes was in similar striatal sites. These results establish that differential patterns of expression of fos/jun genes occur in striatal neurons following exposure to cocaine, a potent psychomotor stimulant. We suggest that these tissue-specific patterns of gene expression may contribute to the response specificity of striatal neurons to stimulation by monoamines including dopamine.
Female preference for trait symmetry in addition to trait size in swordtail fish

Interest in fluctuating asymmetries, random deviations from perfect bilateral symmetry, has spread to studies of sexual selection because of the intriguing idea that females could use the degree of asymmetry of a male trait to assess the genetic quality of potential mates. The evidence that females prefer males with symmetrical sexual signals, however, remains controversial. A problem that applies to most previous studies is that preference for trait size can be misinterpreted as preference for symmetry, even when overall trait size is held constant, if females assess trait size by the largest minimum on one side. If overall trait size is equal between males, the asymmetrical males will have the maximum and minimum trait size, and so preference to mate with symmetrical males could actually reflect a preference to avoid males with the minimum trait on one side. Xiphophorus cortezi females preferred males with symmetrical bar numbers when the minimum number of bars was held constant. The strength of female preference for the symmetrical males was negatively correlated with the strength of preference the same females had for bar number. These results clearly demonstrate that females preferred trait symmetry in addition to trait size.
Effect of intravenous taurine supplementation on plasma, blood cell, and urine taurine concentrations in adults undergoing long-term parenteral nutrition.

Thirty-four adults undergoing long-term par- enteral nutrition (TPN) were treated either with or without in- travenous taurine for � 24 mo. Statistical comparisons were carried out in eight patients randomly assigned to receive intra- venous taurine, usually 10 mg. kg � . d ', and 10 patients not receiving taurine. Compared with normal adults, baseline plasma taunne and urine taurine-creatinine ratios were de- creased in both groups and platelet taurine was reduced in the taurine-treated group. During taurine treatment the mean of the mean values for taurine became normal in plasma and platelets and remained normal in erythrocytes, granulocytes, and lymphocytes; urine taurine-creatinine ratios rose to ap- proximately five times normal. During follow-up, patients not given taurine had plasma, erythrocyte, and granulocyte taurine and urine taurine-creatinine ratios below normal values and the concentrations of taurine-treated patients. Their platelet taurine was also subnormal. Thus, 10 mg taurine . kg ' - d ' in- travenously normalizes plasma and blood cell taunne concen- trations in long-term TPN patients. Am J Clin Nutr 1990;52:846-53.