cssi/SciSciGPT-SciSciNet huggingface dataset:
Thermal Phase Transition of the Dilute s -State Potts and n -Vector Models at the Percolation Threshold

A general theory is given for the quenched dilute $s$-state Potts and $n$-vector models in any dimension $d$. It is shown that for $T\ensuremath{\rightarrow}0$ at the percolation threshold the Potts thermal exponent ${\ensuremath{\nu}}_{T}$ equals the percolation exponent ${\ensuremath{\nu}}_{p}$, implying a crossover exponent $\ensuremath{\varphi}=1$, for any $s$ and $d$. For the $n$-vector model ($ng1$), ${\ensuremath{\nu}}_{T}=\frac{{\ensuremath{\nu}}_{p}}{{\ensuremath{\zeta}}_{R}}$, where ${\ensuremath{\zeta}}_{R}$ is a resistivity critical exponent. Agreement with recent experiments for two-dimensional dilute Ising and Heisenberg systems is excellent.
A review of head-mounted displays (HMD) technologies and applications for consumer electronics

We review in this paper the various architectures that have been proposed in industry to implement see-through head-mounted display (HMD), especially for the consumer electronics market.
Effects of follicle stimulating hormone and luteinizing hormone upon cyclic AMP and cyclic GMP levels in rat ovaries in vitro.

In vitro effects of FSH and LH on adenosine 3′,5′-cyclic monophosphate (cyclic AMP) and guanosine 3′,5′-cyclic monophosphate (cyclic GMP) levels in rat ovarian tissue were studied. Ovaries from immature rats treated with either pregnant mare's serum (PMS) or PMS and human chorionic gonadotropin (hCG) were incubated at 37 C for 30 min in defined medium 199 containing aminophylline (0.1 mg/ml). Increasing concentrations of LH (0.4–10.0 μg) when added to the medium containing ovaries with predominantly follicular tissue (PMS-treated) produced progressive increases in cyclic AMP (29–300%) and concomitant decreases in cyclic GMP (41–70%). FSH (4–100 μg) added to the medium produced comparable changes in nucleotide levels: cyclic AMP increased 52–390% and cyclic GMP decreased 45–80%. Ovaries with predominantly luteal tissue (PMSand hCG-treated) responded differently to the same experimental conditions. LH produced a much greater increase in tissue cyclic AMP levels (209–1280%), whereas FSH produced comparable i...
Contact with infants modulates anxiety-generated c-fos activity in the brains of postpartum rats

Abstract The postpartum period is associated with many behavioral changes, including a reduction in anxiety, which is thought to be necessary for mothers’ ability to appropriately care for infants. In laboratory rats, this reduction in anxiety requires recent contact with pups, but areas of the brain where infant contact influences neural activity to reduce anxiety are mostly unknown. We examined c-fos expression in lactating rats whose pups were removed for 4 h to increase mothers’ anxiety, or not removed to maintain low anxiety in mothers, followed by exposure to the anxiogenic stimuli of either brief handling or handling followed by exposure to an elevated plus maze. Control animals had their litters removed or not, but no further stimulation. A large number of neural sites traditionally implicated in regulating anxiety in male rats were examined, and similar to what is found in male rats, most showed increased Fos expression after handling and/or elevated plus-maze exposure. Litter presence before testing affected Fos expression due to handling or elevated plus-maze exposure only in the ventral bed nucleus of the stria terminalis, dorsal and ventral preoptic area, ventromedial hypothalamus, lateral habenula, and supramammillary nucleus. Contrary to expectations, prior litter presence was associated with more Fos expression in most of these sites after handling and/or elevated plus-maze stimulation, and only after such stimulation. These sites may be of particular importance for how sensory inputs from infants modulate anxiety and other mood states during the postpartum period.
Messianic-City: Ruins, Refuge and Hospitality in Derrida

‘‘Listen first to those who, like myself, did not have to watch TV to know that SOME of L.A. was burning,’’ Derrida wrote to a newsletter in response to the riots triggered by the Rodney King events in 1992, adding, ‘‘L.A. is not anywhere, but it is a singular organization of the experience of ‘anywhere’’’ (‘‘Faxitexture’’ 28). At a time when one hardly needs to watch TV to know that many cities around the world are burning, or are targeted and wounded, bombed and invaded—as if the Biblical injunction, ‘‘Then ye shall appoint you cities to be cities of refuge for you’’ had turned against itself, or had suspended itself, thereby converting cities of refuge into sites of intense hostility—it would be pertinent to recall the many illuminating texts Derrida has composed on cities and how deconstruction is inextricably related to burning, cinders, ashes, ruins, haunting, dissemination and destruction, and at the same time to rebuilding, inheriting, maintaining (maintenant), opening, reconstructing and welcoming. At the same time, it is precisely his evocation of the city as a place of refuge modeled after a certain messianicity, if not messianism, that exposes his own texts to a rigorous rethinking and critique. A number of fascinating readings have been done on Derrida’s concept of hospitality, yet hardly anything has been written on the theme of the city in Derrida, even
The shielding tensor part II: Understanding its strange effects on relaxation

The shielding tensor can be nonsymmetric and thus in general has both symmetric and antisymmetric parts. Relaxation by these two parts of the shielding tensor (chemical shift anisotropy or CSA relaxation) are reviewed and compared with relaxation by the dipole-dipole (DD) mechanism. It is explained how T2 can be equal to (6/7)T1 or to 2T1 in limiting situations for relaxation that involves the shielding tensor. Cross-correlation (or interference) effects between CSA and DD relaxation and the relationship between CSA and spin-rotation relaxation are briefly reviewed.
Black lesbian gender and sexual culture: celebration and resistance.

Lesbian gender expression is a persistent theme in research and writing about lesbian culture. Yet little empirical research has examined the ways lesbian gender functions within the sexual culture of lesbian communities, particularly among lesbians of colour. This study was aimed at documenting and assessing the functions of lesbian gender among African American lesbians. Particular attention was paid to identifying core characteristics of sexual discourses, such as evidence of dominant and resistant sexual scripts and contradictions between messages about sex. This study took the form of a rapid ethnography of an African American lesbian community in the USA using focus groups, individual community leader interviews and participant observations at a weekly open mic event. Findings document how lesbian gender roles translated into distinct sexual roles and expectations that appear to both parallel and radically reject heterosexual norms for sex. The deep roots of the social pressure to date within these ...
The Effect of Electric Field on Sintering and Electrical Conductivity of Titania

The effect of DC electric field on sintering, and on the electrical conductivity of undoped rutile, TiO2 (99.99%), has been investigated at fields ranging from 0 V to 1000 V/cm. The experiments were carried out at a constant heating rate of 10°C/min with the furnace temperatures reaching up to 1150°C. The sintering behavior falls into two regimes: at lower fields, up to 150 V/cm, sintering is enhanced, but densification occurs gradually with time (Type A or FAST sintering). At higher fields sintering occurs abruptly, and is accompanied by a highly nonlinear increase in conductivity, which has been called flash sintering (Type B or FLASH sintering). Arrhenius plots of conductivity yield an activation energy of 1.6 eV in Type A and 0.6 eV in Type B behavior; the first is explained as ionic and the second as electronic conductivity. The evolution of grain size under both types of sintering behavior are reported. These results highlight that the dominant mechanism of field-assisted sintering can change with the field strength and temperature. We are in the very early stages of identifying these mechanisms and mapping them in the field, frequency, and temperature space.
Influence of the calcium oxalate defective 4 (cod4) mutation on the growth, oxalate content, and calcium content of Medicago truncatula

Abstract Calcium oxalate crystal formation has been well documented in plants. The pathway(s) and regulatory mechanism(s) of crystal formation and function, however, remain largely unknown. As a step toward expanding our understanding of crystal formation and function, we characterize the oxalate over-accumulating mutant calcium oxalate defective 4 ( cod4 ). Measurements of oxalate content in the different cod4 tissues showed elevated levels in leaves, stems and pods, compared to the corresponding control tissues. Root oxalate content was similar between cod4 and controls. Microscopic examination of the cod4 tissues revealed that all of the tissues with elevated oxalate content accumulated druse crystals in addition to the prismatic crystals that are present in wild type. With the exception of pods, however, the calcium content did not increase in proportion to the increase in oxalate. Thus, more of the tissue calcium was partitioned into the crystalline form in the leaves and stems from cod4 than controls. Shoot biomass and chlorophyll measurements showed that the cod4 mutation also resulted in an overall reduction in plant growth and chlorophyll content.
Scaling virtual organization clusters over a wide area network using the Kestrel workload management system

This paper presents the results of using the Kestrel workload management system to test operating a Virtual Organization Cluster (VOC) across multiple sites. A Many-Task Computing (MTC) framework based on the Extensible Messaging and Presence Protocol (XMPP), Kestrel presents a special purpose scheduler that can offer better VOC scalability under certain workload assumptions, namely CPU bound processes and bag-of-tasks jobs.Experimental results have shown that Kestrel is capable of operating a VOC of at least 1600 worker nodes with all nodes visible to the scheduler at once. When using multiple sites located in both North America and Europe, the latencies introduced to the round trip time of messages were on the order of 0.3 seconds. To offset the overhead of XMPP processing, a task execution time of 2 seconds is sufficient for a pool of 900 workers on a single site to operate at near 100% use. Requiring tasks that take on the order of 30 seconds to a minute to execute would compensate for increased latency during job dispatch across multiple sites.
An English and Spanish quality of life measure for rheumatoid arthritis

Objective To develop a rheumatoid arthritis–specific health-related quality of life instrument, translate the English instrument into Spanish, and test the scaling assumptions, reliability, validity, and feasibility of both the English and Spanish versions. Methods The development of the Quality of Life–Rheumatoid Arthritis Scale (QOL-RA Scale) involved literature review, consultations with experts, 40 face-to-face interviews, and 5 focus group discussions with multiethnic and multilingual women with rheumatoid arthritis (RA). Translation design facilitated conceptual and linguistic equivalence. Data for the psychometrics came from telephone interviews of a sample of 107 Caucasian/English and 80 Hispanic/Spanish women with RA. The instruments were (a) the Arthritis Impact Measurement Scales 2 (AIMS2), (b) the Lubben Social Network Scale (LSNS), (c) the Center for Epidemiologic Studies–Depression Scale (CES-D), and (d) the QOL-RA Scale. Descriptive statistics, significance tests, Cronbach's alpha technique, correlation, and factor analysis were used. Results The QOL-RA Scale, an 8-item scale, took 2 to 3 minutes to administer. Psychometric analysis revealed that the psychometric attributes and constructs of both English and Spanish questionnaires are comparable (i.e., equivalent). Both versions demonstrated the following: (a) normal distribution of the QOL-RA Scale, roughly symmetrical distributions of the items, equivalent means and standard deviations across items, and less than 10% floor and ceiling effects, (b) Cronbach's alpha coefficients of 0.87–0.90, (c) significant correlations of the QOL-RA Scale with the AIMS2 subscales, LSNS, and CES-D, ranging from 0.25 to 0.66 (P≤ 0.01), and (d) extraction of 2 factors, namely physio-psychological and socio-psychological, that explained 65% to 73% of the variance in the scale scores. Conclusion The QOL-RA Scale, in both English and Spanish versions, appears to meet the assumptions of a summated rating scale and the criteria of relevance, reliability, validity, feasibility, and adaptability to several languages.
New York Medical College: An early center of excellence in American Medical education

Originating in 1850, the New York Medical College was one of the earliest medical schools to adopt the educational reforms advocated by the American Medical Association. This college lengthened the school term, employed more professors than usual and established a separate Board of Censors to approve students for their medical degrees. In addition, the New York Medical College initiated bedside clinical teaching using a 27 bed hospital under its own control. In an era when many medical schools were little more than diploma mills, the New York Medical College created educational reforms that were not adopted by other schools until many years later. Due to a combination of causes the New York Medical College only existed from 1850 to 1864. However, the effort to reform medical education was significant and should not be overlooked. Incidentally, the New York Medical College of 1850 to 1864 was in no way related to the currently existing medical school of the same name.
Thermoelectric Power, Electrical Resistance, and Crystalline Structure of Carbons.

The thermoelectric power $\ensuremath{\Theta}$ and the electric resistance $R$ of soft and hard carbons were investigated as functions of heat-treatment temperature ${T}_{\mathrm{ht}}$ from 1000\ifmmode^\circ\else\textdegree\fi{}C to 3100\ifmmode^\circ\else\textdegree\fi{}C at three ambient temperatures $T$ equal to 90\ifmmode^\circ\else\textdegree\fi{}K, 305\ifmmode^\circ\else\textdegree\fi{}K, and 573\ifmmode^\circ\else\textdegree\fi{}K. The crystalline structure was studied by means of x-ray powder diffraction technique. For a given $T$, with increase of ${T}_{\mathrm{ht}}$ the thermoelectric power of soft carbons goes through a flat minumum at ${T}_{\mathrm{ht}}\ensuremath{\sim}1400\ifmmode^\circ\else\textdegree\fi{}$C, increases quite fast to a maximum at about 2100\ifmmode^\circ\else\textdegree\fi{}C, and subsequently drops down again and continues to do so up to the highest ${T}_{\mathrm{ht}}$. The electric resistance is only very slowly decreasing (plateau) up to ${T}_{\mathrm{ht}}\ensuremath{\sim}2000\ifmmode^\circ\else\textdegree\fi{}$C, with a subsequent rapid decrease up to the highest ${T}_{\mathrm{ht}}$ investigated. The positions of the maximum in $\ensuremath{\Theta}$ and of the corresponding knee in resistance (end of plateau) shifts to higher heat treatments with decrease of ambient temperature $T$. The thermoelectric power is proportional to temperature $T$ in the range of heat treatments below the ${T}_{\mathrm{ht}}$ corresponding to the maximum in $\ensuremath{\Theta}$. The observed dependence of $\ensuremath{\Theta}$ and of $R$ on ${T}_{\mathrm{ht}}$ and $T$ are in good agreement with Mrozowski's energy band scheme for carbons and graphites. A hard carbon prepared from phenol-benzaldehyde resin shows a two-stage graphitization with $\frac{1}{8}$ of the crystalline mass beginning to graphitize at ${T}_{\mathrm{ht}}\ensuremath{\sim}2200\ifmmode^\circ\else\textdegree\fi{}$C and the remainder only above ${T}_{\mathrm{ht}}=2800\ifmmode^\circ\else\textdegree\fi{}$C. Correspondingly the resistance curves show two plateaus ending one at ${T}_{\mathrm{ht}}\ensuremath{\sim}2200\ifmmode^\circ\else\textdegree\fi{}$C and the other at ${T}_{\mathrm{ht}}\ensuremath{\sim}2800\ifmmode^\circ\else\textdegree\fi{}$C. The dependence of $\ensuremath{\Theta}$ on ${T}_{\mathrm{ht}}$ is somewhat similar to that found in soft carbons.
β-Secretase inhibition for the treatment of Alzheimer's disease – promise and challenge

As the number of cases of Alzheimer's disease (AD) rises in all developed countries, the unmet medical need for disease-modifying pharmacotherapy continues to grow. Much of AD research has been focused on the amyloid cascade hypothesis, which states that amyloid-beta-42 (A beta 42), a proteolytic derivative of the large transmembrane protein amyloid precursor protein (APP), plays an early and crucial role in all cases of AD. Consequently, blocking the production of A beta 42 by specific inhibition of the key proteases required for A beta 42 generation is a major focus of research into AD therapy. The identification of beta-secretase, the aspartic protease that generates the N-terminus of A beta 42, has triggered a race to develop drug-like inhibitors of this enzyme, which has become one of the major AD targets. Although the biology of beta-secretase holds great promise, it will be challenging to generate drug-like inhibitors of this unusual enzyme.
LC-mass spectrometry analysis of N- and C-terminal boundary sequences of polypeptide fragments by limited proteolysis

Limited proteolysis is an important and widely used method for analyzing the tertiary structure and determining the domain boundaries of proteins. Here we describe a novel method for determining the N- and C-terminal boundary amino acid sequences of products derived from limited proteolysis using semi-specific and/or non-specific enzymes, with mass spectrometry as the only analytical tool. The core of this method is founded on the recognition that cleavage of proteins with non-specific proteases is not random, but patterned. Based on this recognition, we have the ability to determine the sequence of each proteolytic fragment by extracting a common association between data sets containing multiple potential sequences derived from two or more different mass spectral molecular weight measurements. Proteolytic product sequences derived from specific and non-specific enzymes can be accurately determined without resorting to the conventional time-consuming and laborious methods of SDS-PAGE and N-terminal sequencing analysis. Because of the sensitivity of mass spectrometry, multiple transient proteolysis intermediates can also be identified and analyzed by this method, which allows the ability to monitor the progression of proteolysis and thereby gain insight into protein structures.
Microstructural characterization of SiC/Al and FP/Al metal matrix composites subjected to dynamic loadings

The Split Hopkinson Pressure Bar technique was used to study the dynamic response of silicon carbide particle- and whisker-reinforced aluminium (SiC/Al-P and SiC/Al-W) and continuous Fibre FP-reinforced aluminium (FP/Al), metal matrix composites, subjected to high strain rates in the range of 300–3200 s−1. The response of these composites was characterized by macroscopic and microscopic observations. Experiments on SiC/Al-W and FP/Al were conducted with the whiskers/fibres oriented in the axial, as well as, in the transverse direction with respect to the loading direction. It was observed that for the silicon carbide-reinforced metal matrix composites, the dynamic flow stress values were consistently higher than the static/quasi-static values. Experiments conducted on FP/Al with the fibres oriented transversely to the loading direction, revealed failure stress values considerably lower than the static/quasi-static values. This anomalous behaviour was attributed to the predominantly shear mode failure of the material. Microscopic observations using optical and scanning electron microscopy corroborate the macroscopically observed behaviour.
Shakespeare's Individualism

Shakespeare was a libertarian. This is, in a nutshell, the argument of Peter Holbrook's Shakespeare's Individualism, a celebration of Shakespeare as a champion of the uncompromising individual, the...
Expression of genes involved in symbiotic carbon and nitrogen transport in Pinus taeda mycorrhizal roots exposed to CO2 enrichment and nitrogen fertilization

As atmospheric carbon dioxide (CO2) concentrations rise, one important mechanism by which plants can gain greater access to necessary soil nutrients is through greater investment in their mycorrhizal symbionts. In this study, we tested the hypotheses that (1) plants increase C allocation to ectomycorrhizal fungi (EMF) under elevated CO2 conditions, (2) N fertilization decreases C allocation to EMF, and (3) EMF activity at the site of symbiotic C and nutrient exchange is enhanced with CO2 enrichment. To test these hypotheses, we examined expression levels of Pinus taeda genes encoding monosaccharide transport (MST) and ammonium transport (AMT) proteins thought to be involved in symbiotic C and N movement, respectively, from mycorrhizal root tips exposed to CO2 and N fertilization. We also examined EMF ribosomal RNA expression (18S rRNA) to determine EMF activity. There was a trend toward lower relative MST expression with increased CO2. AMT expression levels showed no significant differences between control and treatment plots. EMF 18S rRNA expression was increased in CO2-enriched plots and there was a marginally significant positive interactive effect of CO2 and N fertilization on expression (p = 0.09 and 0.10, respectively). These results are consistent with greater C allocation to EMF and greater EMF metabolic activity under elevated CO2 conditions, although selective allocation of C to particular EMF species and greater fungal biomass on roots are plausible alternative hypotheses.
Torsion angle analysis of glycolipid order at membrane surfaces.

A method is presented for determining the average glycosidic torsion angles and motion about those angles for a glycolipid headgroup at a model membrane surface. Dipolar and quadrupolar coupling constants were previously collected on the headgroup of beta-dodecyl glucoside embedded in phospholipid/detergent bilayers which orient in a magnetic field (Sanders, C.R., and J.H. Prestegard. 1991. J. Am. Chem. Soc. 113:1987–1996). These observables are expressed as averages of second order spherical harmonics, and Wigner rotation matrices are used here to transform the spherical harmonics from the laboratory frame to a set of frames which allow motional averaging to be described as the result of simple bond rotations. Euler angles corresponding to rotations about glycosidic torsion angles phi and psi are chosen to best reproduce experimental coupling constants, using models which have varying degrees of motional averaging. These models include a rigid headgroup, axially symmetric headgroup motion, and independent motion about each torsion angle in a square well potential. The square well model proves to be significantly better than the rigid model in reproducing experimental observations and it offers a more physically meaningful description of motion than the axially symmetric model. The structures obtained, assuming a square well potential, are compared to potential energy maps for the glycolipid torsional angles to illustrate the need for inclusion of the membrane interface in energetic modeling of glycolipid conformations.
Effect of potassium salts on alleviation of lime-induced chlorosis in soybean

Abstract Studies were conducted to determine the efficacy of K salts in alleviating lime‐induced chlorosis. Greenhouse studies using a Gibbon silt loam [fine‐silty, mixed (calcareous), mesic Typic Haplaquoll] and a 1: 1 mixture of Gibbon soil and washed sand were conducted with KCl, KNO3, K2SO4, K2HPO4, or KHCO3 applied at rates of 0, 250, and 500 mg K/kg soil. An FeEDDHA treatment was included for comparison. Similar studies were conducted at two field sites known to produce lime‐induced chlorosis. Potassium salts were applied at 0, 20, and 40 g K/m of row. In the greenhouse, plants treated with KCl, KNO3, and K2SO4 on Gibbon soil were less chlorotic than controls or plants treated with K2HPO4, or KHCO3. No K treatment totally alleviated chlorosis except FeEDDHA. Chlorophyll correlated positively with chlorosis rating. No relationship was found between leaf Fe uptake and chlorosis. Plants grown in soil/sand exhibited no chlorosis and had lower Fe uptake than plants grown in Gibbon soil. Thus chlorosis wa...
Unilateral torsion of spermatic cord in men: Effect on Leydig cell

Abstract In our previous studies, we reported that short-term unilateral spermatic cord torsion had no adverse effect on the germ cells and the Sertoli cell in the contralateral testis of men. As an extension of our earlier investigations on the testicular pathophysiology in humans after unilateral spermatic cord torsion, the present study was undertaken to assess the Leydig cell function employing both fine structural and morphometric analysis in patients with short-term spermatic cord torsion. Bilateral testicular biopsy samples obtained from 4 men (15–19 years) with short-term unilateral torsion of the spermatic cord and from a control group of 6 men (15–40 years) were used innthe present investigation. No appreciable difference in the Leydig morphology was noted between the biopsy samples from control and the contralateral testes. This was substantiated by morphometric analysis. The present study clearly indicates that patients with unilateral torsion of the spermatic cord may not essentially have bilateral testicular abnormalities, as suggested by the previous investigators. This report, thus lends further support to our earlier contention that alteration in microcirculation is quite likely the earliest and possibly the most significant contributor to the contralateral testicular damage in man after ipsilateral spermatic cord torsion.
An International Comparison of Factory Productivity

For the plant manager there are many suggested remedies for increased plant productivity. Detailed survey data from 555 factories, principally in the US, Europe and Korea, are used to examine the factors that contribute to productivity. Regression analysis is employed with five distinct measures of productivity and productivity gain and the results indicate a number of key variables are responsible. Many similarities are reported across the three samples analysed, but three factors stand out: improved flow of materials; investment in new technology; and human resource initiatives.
Endoscopic ultrasound as an adjunctive evaluation in patients with esophageal motor disorders subtyped by high-resolution manometry

Background and aims Esophageal motor disorders are a heterogenous group of conditions identified by esophageal manometry that lead to esophageal dysfunction. The aim of this study was to assess the clinical utility of endoscopic ultrasound in the further evaluation of patients with esophageal motor disorders categorized using the updated Chicago Classification.
Formation of Palladium Bis(amine) Complexes from Reaction of Amine with Palladium Tris(o-tolyl)phosphine Mono(amine) Complexes

Palladium mono(benzylamine) complexes Pd[P(o-tolyl)3](p-C6H4CMe3)[H2NBn]X (X = Cl (7), Br (8), I (14)) react reversibly with benzylamine in CDCl3 at 25 °C via P(o-tolyl)3 displacement to generate the corresponding bis(amine) derivatives trans-Pd(p-C6H4CMe3)[H2NBn]2X (X = Cl (17), Keq = 0.18 ± 0.02; Br (16), Keq = 0.14 ± 0.01; I (18), Keq = 0.10 ± 0.01). Complexes 16−18 were isolated from reaction of the palladium aryl halide dimers {Pd[P(o-tolyl)3](p-C6H4CMe3)(μ-X)}2 (X = Cl (4), Br (5), I (6)) and excess benzylamine as the corresponding mono(benzylamine) solvate Pd(p-C6H4CMe3)[H2NBn]2X·H2NBn (X = Br (16·H2NBn), Cl (17·H2NBn), I (18·H2NBn)). IR and 1H NMR spectroscopy of 16·H2NBn indicated the presence of N−H···X (X = N, Br, Pd) hydrogen bonds in both the solid state and solution. The equilibrium constant for the formation of 16 and P(o-tolyl)3 from 8 and benzylamine ranged from 0.066 ± 0.005 in CD2Cl2 to 3.6 ± 0.3 in THF-d8 and in C6D6 ranged from 0.90 ± 0.07 at 25 °C to 0.44 ± 0.04 at 77 °C (ΔG°298 K = ...
The shear rheology of thin compressed liquid films

AbstractThin liquid films at elevated pressures have a unique property. A sufficiently high shear stress can be generated in steady shear without encountering the thermal softening limit or interfacial slip that it is possible to observe, in low molecular weight liquids, various non-Newtonian effects ordinarily thought to be reserved for high polymers. These include shear thinning, viscoelasticity and cohesive failure. The relevant rheology literature is reviewed. Only the properties of the continuum are addressed here, omitting near-surface effects.Within the last 10 years in particular, both experiment and molecular simulation have shown that many analogies may be made between lubricants and liquid polymers when allowance is made for the much shorter relaxation time of the low molecular weight liquid. Shear thinning, elasticity and liquid failure are all aspects of the shear response of thin films of low molecular weight liquids at elevated pressures.
The regulatory function of potato pyruvate dehydrogenase.

Abstract The effect of selected metabolites on the activity of potato pyruvate dehydrogenase has been studied. NADH is a potent competitive inhibitor with respect to NAD, and the content of NAD and NADH in whole tissue suggests that the balance between them may afford a fine regulatory mechanism for pyruvate dehydrogenase. Acetalhyde is not inhibitory. While glyoxylate competitively inhibits pyruvate dehydrogenase, the inhibitory characteristics fail to make glyoxylate an effective regulator of pyruvate oxidation. Acetyl CoA is a moderate competitive inhibitor with CoA, and its effect is enhanced by NADH, ATP, ADP, and AMP inhibit pyruvate dehydrogenase by binding Mg 2+ .
Hereditary breast cancer: an update on risk assessment and genetic testing in 2015

The last 5 years have brought significant innovation and advancement in the genetics of breast cancer. This clinical opinion aims to summarize and update current approaches to the care of women at risk for a hereditary predisposition to breast cancer. Implications of the BRCA mutation and several other hereditary syndromes will be discussed. Risk assessment and criteria for referral to cancer genetic professionals as well as high-risk screening and prophylactic options will be reviewed. Finally, the newly available genetic cancer panels and implications of mutations in some of these lesser known genes will be discussed. As the field of cancer genetics continues to evolve, the education of medical students, residents, and faculty will be paramount to identify appropriate candidates for genetic counseling and testing in conjunction with cancer genetic professionals.
Bringing Consumer Behavior to the Workbench: An Experiential Approach

This article outlines an experiential project to be used in an undergraduate consumer behavior course that encourages students to focus on the integration of course concepts into a coherent framework. The project not only illustrates how marketing strategy depends on market behavior, but also facilitates students' ability to synthesize and apply information.
Reduced sickle erythrocyte dehydration in vivo by endothelin-1 receptor antagonists.

Elevated plasma levels of cytokines such as endothelin-1 (ET-1) have been shown to be associated with sickle cell disease (SCD). However, the role of ET-1 in the pathophysiology of SCD is not entir...
River reversals into karst springs: A model for cave enlargement in eogenetic karst aquifers

Most conceptual models of epigenic conduit development assume that conduits sourcing karst springs form as water that is undersaturated with respect to carbonate minerals flows from recharge to discharge points. This process is not possible in springs fed by distributed recharge that is transmitted through aquifer matrix porosity, such as unconfined aquifers in eogenetic carbonate rocks. Diffusely recharged water has a long residence time within the aquifer, and thus would have equilibrated with the aquifer rocks prior to discharge to the conduits. The upper Floridan aquifer has high matrix permeability (∼10 −13 m 2 ), and many springs lack discrete inputs of undersaturated allogenic water in their recharge areas. Consequently, another explanation for their development is necessary. During flooding of the Suwannee River in north-central Florida, water highly undersaturated with respect to carbonate minerals commonly recharges the upper Floridan aquifer through spring vents, and solution scallops oriented away from the vents suggest most dissolution along conduit walls occurs during these flow reversals. During a single flow reversal at the Peacock Spring cave system, flood water was capable of dissolving up to 3.4 mm of the conduit wall rock. Dissolution occurs as flow reversals follow preexisting features that include joints and paleo–water-table caves. Lack of speleothems in conduits in the upper Floridan aquifer has been used as evidence that the caves formed in the phreatic zone; however, flooding would dissolve any speleothems that may have formed during previous subaerial exposure. Conduit enlargement during flow reversals suggests that dissolution can progress in the normal upstream directions, and this process may be an important driver of dissolution in any karst aquifer with outflows to surface water that are subject to flooding. Flow reversals would also introduce dissolved organic carbon and oxygen into the groundwater and provide important energy sources for cave ecosystems as well as altering redox chemistry of the aquifer water.
Obstructive sleep apnoea among HIV patients

The development of body weight gain and lipodystrophy due to antiretroviral therapy may lead to disturbances in sleep, particularly the obstructive sleep apnoea (OSA) syndrome. A retrospective review of the medical records of consecutively identified HIV-infected subjects who were diagnosed with OSA by overnight polysomnography between January 1, 2003 and December 31, 2004 was performed. Twelve HIV-infected subjects with OSA confirmed by polysomnography (total apnoea/hypopnoea index ≥ 5) were identified. Daytime somnolence, fatigue, and snoring were the most common symptoms identified. Eleven (92%) subjects were overweight/obese, and seven (58%) had lipodystrophy. Eleven (92%) had a neck size ≥40.0 cm. Increased neck circumference, overweight or obese body mass index, and lipodystrophy are therefore potential risk factors for OSA among HIV patients. Clinicians caring for HIV patients with these characteristics should inquire about daytime somnolence, fatigue, and snoring and consider evaluation for a slee...
Depth variations in hydraulic conductivity within a single lift of compacted clay

Compacted clay liners are commonly used as components of the lower portion of composite double liner systems for hazardous waste containment. Because the overlying leachate collection and removal systems and the FMLs are not perfect leachate still comes into contact with the lower liner and thus makes it critical that the clay liner component be constructed to achieve the lowest possible hydraulic conductivity. This research was conducted to evaluate the effects of clod size on the hydraulic conductivity of compacted soils and the uniformity of conductivity with depth within a lift of compacted soil. Two subsoils, one from the Beaumont series (smectitic) and one from the Kosse series (kaolinitic), were evaluated in the laboratory and then compacted in large fixed wall permeameters using maximum clod sizes of <2.5, <5.0, and <7.5 cm to a compacted lift thickness of 23 cm. Measurements were made of the hydraulic conductivity of the entire lift, the lower two thirds of the lift, and the lower one third of the lift. The results show that the conductivity of the lower one third of the lift can be as great as 8.7 times that measured for the entire lift and indicates that liners need to be constructed using thin lifts to achieve more uniform low conductivity throughout the liner. The data also indicated that under the carefully controlled conditions of this study and with the clod sizes used, the clod size did not have a significant effect on the hydraulic conductivity of the soils tested. Soil bulk density was poorly correlated with hydraulic conductivity and indicates that measuring the bulk density of a compacted soil is an inadequate method for assuring low hydraulic conductivity. Measurements of the time to the first appearance of leachate indicated that 8 to 17 d are required for water to penetrate a 23 cm thick compacted liner with an average conductivity of 1 × 10−7 cm s−1.
Age of Adult Worms of Echinostoma caproni Does Not Affect Development of Miracidia

The effect of the age of adult Echinostoma caproni on egg development was studied. The percentage of fully developed miracidia was determined in eggs derived from adult worms obtained from laboratory mice at 2, 4, 6, and 8 wk postinfection (PI). Regardless of the age of worms from which the eggs were obtained, the percentage of fully developed miracidia was always >90%, and 60–80% of the eggs hatched. Several previous studies have shown that eggs derived from 2- to 4-wk-old E. caproni yielded miracidia that infected Biomphalaria glabrata snails. Results of the present study on E. caproni were in marked contrast to previous results with Echinostoma friedi, for which viable eggs were not obtained at 2 and 3 wk PI and maximal infectivity of miracidia in snails was obtained from eggs derived from worms collected at 8 and 9 wk PI. Further studies are needed to determine if the egg viability of other species in the “revolutum” group follow that of E. caproni or E. friedi.
Managing expert systems for New Federalism

Change in the locus of operating knowledge that accompanies 'New Federalism' policies implies different design and knowledge-engineering approaches for expert system applications. An expert systems strategy to implement a New Federalism approach in a Congressionally-mandated regulatory program is discussed. Tactical needs created by competition with conventional knowledge-delivery mechanisms are analyzed. Three knowledge-engineering tactics especially suitable for developing expert systems in this application environment are described. >
Regulating existing power plants under the U.S. Clean Air Act: Present and future consequences of key design choices

Abstract In June 2014, the U.S. EPA released its proposed rules to regulate carbon dioxide emissions from existing fossil fuel power plants, triggering considerable debate on the proposal’s design and its environmental and economic consequences. One question not addressed by this debate is this: What if the EPA regulations turn out to be inadequate to address future mitigation goals? That is, what will the landscape for future policies look like if these regulations turn out to be just an interim measure? This analysis compares potential short- and long-term consequences of several key regulatory design choices, including mass-based versus rate-based standards, tradable versus non-tradable standards, and differentiated versus single standards. It finds that long-term consequences may be significant in terms of the legacy they leave for future policy revisions: tradable standards lead to lower electricity prices and become weaker over time; differentiated tradable standards lead to relatively greater investment in coal retrofits; non-tradable standards lead to relatively greater retirement of coal capacity. It may be the case that key policy choices entail one set of trade-offs if proposed EPA rules are viewed as relatively permanent and final and another set of tradeoffs if the rules are viewed as an interim solution.
Statistical Equivalent Models for Computer Simulators with an Application to the Random Waypoint Mobility Model

Statistical Equivalent Models, or SEMs, have recently been proposed as a general approach to study computer simulators. By fitting a statistical model to the simulator's output, SEMs provide an efficient way to quickly explore the simulator's result. In this paper, we develop a SEM for random waypoint mobility, one of the most widely used mobility models employed by network simulators in the evaluation of communication protocols for wireless multi-hop ad hoc networks (MANETs). We chose the random waypoint mobility model as a case study of SEMs due to recent results pointing out some serious drawbacks of the model (e.g., [1]). In particular, these studies show that, under the random waypoint mobility regime, average node speed tends to zero in steady state. They also show that average node speed varies considerably from the expected average value for the time scales under consideration in most simulation analysis. In order to investigate further the behavior of the random waypoint model, we developed a SEM that captured speed decay over time under random waypoint mobility using maximum speed and terrain size as input parameters. A Bayesian approach to model fitting was employed to capture the uncertainty due to unknown parameters of the statistical model. The SEM is given by the posterior predictive distributions of the average node speed as a function of time. A direct result from our model is that, by characterizing average node speed as a function of time, our approach provides an accurate estimate of the “warm-up” period required by simulations using the random waypoint mobility model. Simulation data from the “warmup” period can then be discarded to obtain accurate protocol performance results. Given that random waypoint mobility is still, by far, the most widely used mobility model in the evaluation of MANETs, the contribution of this work is potentially significant as it allows network protocol designers to continue to use the original random waypoint mobility model and yet obtain accurate results characterizing MANET protocol performance.
Age-related decline in chondrocyte response to insulin-like growth factor-I: The role of growth factor binding proteins

The synthetic activity of chondrocytes in articular cartilage declines with age, possibly as a result of decreased sensitivity to anabolic growth factors such as insulin-like growth factor-I. The sensitivity of these cells to insulin-like growth factor-I is regulated, in part, by the synthesis of insulin-like growth factor-I binding proteins. We hypothesized that, as cartilage ages, an increase in the expression of these binding proteins suppresses the synthetic response of chondrocytes to insulin-like growth factor-I. To test this hypothesis, we measured proteoglycan synthesis (incorporation of [35S]sulfate per cell) in alginate cultures of chondrocytes from the articular cartilage of 1, 3, 12, and 24-month-old rats. A dose-response to insulin-like growth factor-I was determined for cells from each age group; incorporation of [35S]sulfate per cell declined with age, regardless of the dose. The sharpest decline was found between cells from the 1 and 3-month-old groups. Using the Western ligand blot technique, we then compared the expression of insulin-like growth factor-I binding protein in chondrocytes from the 1 and 3-month-old rats and found that it was increased in the cells from the older animals. Recombinant insulin-like growth factor-3, when added to the cell cultures of the 1-month-old rats, inhibited incorporation of [35S]sulfate and blocked responses to insulin-like growth factor-I. These findings suggest that the age-related decline in the synthetic response of chondrocytes to insulin-like growth factor-I results, at least in part, from increased expression of insulin-like growth factor binding protein.
Not all sugars are created equal: some mask aversive tastes better than others in an herbivorous insect.

Manduca sexta caterpillars are unusual because they exhibit strong peripheral gustatory responses to sugars, but nevertheless fail to show immediate appetitive responses to them. We hypothesized that the primary function of the peripheral gustatory response to sugars is to mask the taste of noxious compounds, which abound in host plants of M. sexta . We compared 10 s biting responses to water with those to mixtures of a noxious compound [caffeine (Caf) or aristolochic acid (AA)] and various combinations of sugars [i.e. sucrose (Suc), glucose (Glu), inositol (Ino), Suc+Glu, Suc+Ino or Glu+Ino]. The biting assays indicated that the aversive taste of AA was completely masked by Suc+Ino, and partially masked by Suc+Glu, Glu+Ino and Suc, whereas that of Caf was completely masked by Suc+Ino and Suc+Glu, and partially masked by Glu+Ino, Suc and Ino. To examine the contribution of the peripheral taste system to the masking phenomenon, we recorded responses of the maxillary gustatory sensilla to each stimulus mixture. The sugars differed greatly in their capacity to suppress peripheral gustatory responses to AA and Caf: Suc+Ino and Suc+Glu produced the greatest suppression, and Glu and Ino the least. Further, the extent to which each sugar stimulus suppressed the peripheral gustatory responses to AA reliably predicted the extent to which it masked the taste of AA in biting assays; no such predictive relationship was observed for the sugar/Caf mixtures. We conclude that some, but not all, sugars act on both peripheral and central elements of the gustatory system to mask the taste of noxious compounds.
William Leiss on Lifting Technology's Thumb*

Philosophers need not be located in departments of philosophy in order to be worth reading. Here is a work eminently warranting attention from professional philosophers, perhaps all the more because its author, William Leiss (who earned a Ph.D. in philosophy in 1969 but has never held a formal faculty position in that subject) writes from a variety of alternative perspectives. His first academic position was in Political Science and Environmental Studies at the University of Regina. From there he travelled to York University as Associate Professor of Environmental Studies, taking a year out to serve as Associate Professor of Sociology at the University of Toronto before returning to York and again adding Political Science to his duties in Environmental Studies. Since 1980 he has been Professor of Communication at Simon Fraser University. Although originally a New Yorker, with academic credentials from south of the border, he now writes with distinctly Canadian examples, outlook and style.
Real-time emulation of indoor multipath propagation channels using statistical and deterministic FIR models and acoustic charge transport technology

The results of practical indoor multipath channel emulation based on acoustic charge transport (ACT) technology in general and the ACT programmable transversal filter (PTF) in particular are presented. The ACT PTF is shown to be an ideal finite impulse response (FIR) filter for emulating indoor multipath channels. Its time duration supports the measured excess delays reported for indoor multipath channels. Its bandwidth supports the requirements of state of the art commercial terrestrial spread spectrum communication links. Its programmable nature lends itself to statistical as well as deterministic FIR models. The speed with which the ACT PTF may be reprogrammed is shown to enable real-time emulation. It is also shown that programmable FIR filtering with ACT technology will soon be capable of emulating urban multipath in real time.