cssi/SciSciGPT-SciSciNet huggingface dataset:
A Simple Autocorrelation Algorithm for Determining Grain Size from Digital Images of Sediment

ABSTRACT Autocorrelation between pixels in digital images of sediment can be used to measure average grain size of sediment on the bed, grain-size distribution of bed sediment, and vertical profiles in grain size in a cross-sectional image through a bed. The technique is less sensitive than traditional laboratory analyses to tails of a grain-size distribution, but it offers substantial other advantages: it is 100 times as fast; it is ideal for sampling surficial sediment (the part that interacts with a flow); it can determine vertical profiles in grain size on a scale finer than can be sampled physically; and it can be used in the field to provide almost real-time grain-size analysis. The technique can be applied to digital images obtained using any source with sufficient resolution, including digital cameras, digital video, or underwater digital microscopes (for real-time grain-size mapping of the bed).
Discourse Analysis and the Study of Educational Leadership.

Purpose – The purpose of this paper is to provide an overview of the current and past work using discourse analysis in the field of educational administration and of discourse analysis as a methodology. Design/methodology/approach – Authors reviewed research in educational leadership that uses discourse analysis as a methodology. Findings – While discourse analysis has been used in the field, little work has been done that explores “leadership” as a discourse practice. Originality/value – Increased use of discourse analysis in the field might unearth the ways principals and superintendents are creators of discourse and mediators of the discourses of others.
Evasion of host defense by in vivo-produced protoplast-like cells of the insect mycopathogen Beauveria bassiana.

In vivo cells (hyphal bodies) of the hyphomycetous insect pathogen Beauveria bassiana collected from host Spodoptera exigua larval hemolymph were osmotically sensitive and lacked a well-defined cell wall. In light and electron microscope studies, a galactose-specific lectin purified from S. exigua hemolymph, concanavalin A (specific for alpha-mannose), and a polyclonal antibody to B. bassiana cell walls all bound to surfaces of in vitro-produced B. bassiana blastospores; however, none of these probes labelled the thin layer of extracellular material covering the plasma membranes of hyphal bodies. These cells were observed freely circulating in S. exigua hemolymph at 36 h postinfection, although immunocompetent hemocytes were known to be present. Additionally, association of hyphal bodies with hemocytes in monolayers was significantly less than for opsonized in vitro blastospores or submerged conidia. The absence of antigenically important galactomannan components on in vivo cells may therefore allow these cells to escape recognition and phagocytosis. Lack of structural components (e.g., chitin, as evidenced by the absence of binding of wheat germ agglutinin) may also be important with respect to evasion of host cellular defense mechanisms. Production of wall material resumed 48 to 60 h postinfection and therefore may coincide with loss of phagocytic capabilities of the hemocytes due to immunosuppressive effects of fungal metabolites. The protoplast-like cells may be formed by the action of hydrolytic enzymes in the hemocytes or by inhibition of fungal cell wall synthetases. Images
Franchisee Associations as Sources of Bargaining Power? Some Evidence

The empirical literature in economics and strategy on contract structure, including on franchise contract structure, has been largely based on agency and transaction cost theories. The effects of bargaining power have been much less studied. This paper considers the role of independent franchisee associations in franchising relationships as a means to test for the presence of bargaining power effects. We find that the presence or absence of a franchisee association is significantly related to each of three key contractual and relationship characteristics: contract duration, noncompete stringency, and terminations/nonrenewals. This suggests that bargaining power should be accounted for in studies of contract structure and relationship outcomes
Genomic dysregulation in gastric tumors.

Gastric cancer is among the most common human malignancies and the second leading cause of cancer-related death. The different epidemiologic and histopathology of subtypes of gastric cancer are associated with different genomic patterns. Data suggests that gene expression patterns of proximal, distal gastric cancers-intestinal type, and diffuse/signet cell are well separated. This review summarizes the genetic and epigenetic changes thought to drive gastric cancer and the emerging paradigm of gastric cancer as three unique disease subtypes. J. Surg. Oncol. 2013;107:237–242. © 2012 Wiley Periodicals, Inc.
Multi-octave cavity-backed four-arm slot spiral for multi-mode operation

A design of a wideband multi-mode four-arm spiral antenna is presented. In order to achieve a unidirectional and efficient mode 1 and 2 radiation, the spiral is cavity-backed and resistively-loaded. The resistive loading is implemented as a necessary compromise to maintain reasonable pattern and impedance match with the reflective backing over the operating bandwidth. Numerical simulations are conducted to assess the VSWR, axial ratio, and gain performances of the antenna for different resistor tapers and modes of operation. Guidelines to design a multi-mode spiral with VSWR < 2.5, axial ratio < 3 dB, and nominal gain of 6 dBic over multi-octave bandwidth is highlighted.
Fitness Level and Body Composition are Associated with Inflammation in Non-obese Children

Childhood obesity and poor fitness are associated with insulin resistance (IR), risk for coronary heart disease (CHD), and type 2 diabetes mellitus. Elevated markers of inflammation (e.g., C-reactive protein [CRP]) are independent predictors of CHD. Whether higher percent body fat and poor fitness in non-obese children are associated with evidence of inflammation and IR is unclear. We evaluated 75 children with non-obese body mass index (BMI) for age (<95th percentile), ages 11-14 years for fasting insulin, glucose, adiponectin, CRP, body composition, and maximum oxygen-consumption (VO2max). CRP correlated positively with body composition (BMI z-score, p = 0.00062; percent body fat, p = 0.00007; and total body fat in grams, p = 0.00006) and negatively with VO2max, p = 0.036. Using multivariate analysis, VO2max and percent body fat were both independent predictors of CRP. Fasting insulin and insulin resistance as assessed by QUICKI did not correlate with CRP, fitness, or fatness in these non-obese children. Adiponectin showed no significant correlations, and gender did not influence correlation analyses. We conclude that in non-obese children, low fitness and higher body fat are both associated with inflammation (i.e., higher levels of CRP). This observation strengthens the importance of promoting both fitness and healthy body composition in all children.
Dielectric Stack Filters for Ex Situ and In Situ UV Optical-Fiber Probe Raman Spectroscopic Measurements

Dielectric stack interference filters can be used in conjunction with a high-throughput single-stage spectrograph to facilitate the measurement of high signal-to-noise (S/N) ultraviolet (UV) Raman spectra with 228.9-nm and 244-nm excitation wavelengths. Placed between the sample and the spectrograph, these filters reflect Rayleigh scattering while transmitting Stokes-shifted Raman scattering. We have measured UV Raman bands from solid, highly scattering samples down to a 290-cm -1 shift from the Rayleigh line. The high throughput of the filtered single-stage spectrograph enables the measurement of UV Raman spectra from photo-labile samples, including DNA and the energetic materials pentaerythritol tetranitrate (PETN) and trinitrotoluene (TNT), with sufficiently low excitation powers and short accumulation times to minimize photo-alteration. High S/N UV preresonance and resonance Raman are obtained for PETN and TNT within 1 s, indicating the possible application of UV Raman spectroscopy as a rapid, highly selective screening methodology for the detection of trace levels of contraband explosives. Furthermore, the incorporation of these dielectric filters within a UV optical-fiber Raman probe head provides simultaneous Rayleigh rejection and removal of background silica Raman scattering. With the use of a 244-nm UV optical-fiber probe, we measured Raman spectra from 100 nM to 10 mu M concentrations of polycyclic aromatic hydrocarbon (PAH) in water, even in the presence of an equimolar concentration of the visible fluorophore rhodamine 6G (R6G). Thus, we demonstrate the potential of UV Raman optical-fiber probes for minimally invasive in situ real-time monitoring at low analyte concentrations and within environments in which fluorescence backgrounds would prevent measurements with visible Raman optical-fiber probes.
Policy-based secure deletion

Securely deleting data from storage systems has become difficult today. Most storage space is provided as a virtual resource and traverses many layers between the user and the actual physical storage medium. Operations to properly erase data and wipe out all its traces are typically not foreseen, particularly not in networked and cloud-storage systems. This paper introduces a general cryptographic model for policy-based secure deletion of data in storage systems, whose security relies on the proper erasure of cryptographic keys. Deletion operations are expressed in terms of a policy that describes data destruction through deletion attributes and protection classes. The policy links attributes as specified in deletion operations to the protection class(es) that must be erased accordingly. A cryptographic construction is presented for deletion policies given by directed acyclic graphs; it is built in a modular way from exploiting that secure deletion schemes may be composed with each other. The model and the construction unify and generalize all previous encryption-based techniques for secure deletion. Finally, the paper describes a prototype implementation of a Linux filesystem with policy-based secure deletion.
Two reduced form air quality modeling techniques for rapidly calculating pollutant mitigation potential across many sources, locations and precursor emission types

Abstract Due to the computational cost of running regional-scale numerical air quality models, reduced form models (RFM) have been proposed as computationally efficient simulation tools for characterizing the pollutant response to many different types of emission reductions. The U.S. Environmental Protection Agency has developed two types of reduced form models based upon simulations of the Community Multiscale Air Quality (CMAQ) modeling system. One is based on statistical response surface modeling (RSM) techniques using a multidimensional kriging approach to approximate the nonlinear chemical and physical processes. The second approach is based on using sensitivity coefficients estimated with the Decoupled Direct Method in 3 dimensions (CMAQ-DDM-3D) in a Taylor series approximation for the nonlinear response of the pollutant concentrations to changes in emissions from specific sectors and locations. Both types of reduced form models are used to estimate the changes in O 3 and PM 2.5 across space associated with emission reductions of NO x and SO 2 from power plants and other sectors in the eastern United States. This study provides a direct comparison of the RSM- and DDM-3D-based tools in terms of: computational cost, model performance against brute force runs, and model response to changes in emission inputs. For O 3 , the DDM-3D RFM had slightly better performance on average for low to moderate emission cuts compared to the kriging-based RSM, but over-predicted O 3 disbenefits from cuts to mobile source NO x in very urban areas. The RSM approach required more up-front computational cost and produced some spurious O 3 increases in response to reductions in power plant emissions. However the RSM provided more accurate predictions for PM 2.5 and for predictions of very large emission cuts ( e.g. −60 to −90%). This comparison indicates that there are some important differences in the output of the two approaches that should be taken under consideration when interpreting results for a given application.
Interclause relations and clausal processing

In two experiments subjects were interrupted while listening to a two-clause sentence just before the last word of either the initial clause or the final clause. In Experiment I subjects were timed on their decision about whether a verb—object phrase was consistent in meaning with the sentence fragment they had just heard. Overall these decisions were made more quickly when a main clause was interrupted than when a subordinate clause was interrupted, but the size and direction of main—subordinate differences varied with the causal—temporal properties of subordinate clauses. In Experiment II subjects were timed on their decisions about whether a particular probe word had occurred in the sentence fragment. Target position effects differed for main and subordinate clauses, but again, these effects were related to causal—temporal relations between clauses. The two experiments together suggest that interclause semantic relations affect the immediate processing of clauses.
QUANTUM COIN-TOSSING IN A BAYESIAN JEFFREYS FRAMEWORK

Abstract The Jeffreys' reparameterization-invariant prior for the classical problem of tossing a coin (with its possible binary outcomes designated ±1) is the arc-sine distribution, 1 π (1 − z 2 ) 1 2 , where z ∈ [−1, 1] is the (long-run) expected value intrinsic to the coin. It is demonstrated here that the analogous prior for the problem of measuring a two-level quantum system — represented by a 2 × 2 density matrix ϱ parameterized by points ( x , y , z ) in the Bloch sphere (unit ball) — along two orthogonal ( Y and Z ) axes is 1 2 π(1 − y 2 − z 2 ) 1 2 , where y is the expected value along the Y -axis and z that along the Z -axis. This contention rests upon the identification of ϱ as the covariance matrix of a bivariate complex normal distribution over the vectors (φ) of two-dimensional complex Hilbert space. The identification, in turn, is based upon quantum probabilistic arguments of Bach, supplemented by an invocation of the principle of maximum entropy. In addition, the Jeffreys' priors are presented for several sets of pairs (entangled and not) of two-level systems.
Estimating Dirichlet's integral and electrical conductance for systems which are not self-adjoint

In simple electrical flow problems the Dirichlet integral of the potential function gives the electrical conductance. Moreover the Dirichlet integral of an arbitrary function satisfying the boundary condition gives an upper bound for the conductance. This last property (Dirichlet's principle) does not hold if the boundary value problem is not self-adjoint. This paper develops new algorithms for estimating the conductance. The proof of these algorithms replaces the Dirichlet principle with the elliptic maximum principle. There is an analogous discrete problem for conductance of electrical networks of the non-reciprocal type. The conductance problem both for continuous bodies and discrete networks can be treated by a single postulational theory.
Multiplicity reactivation, marker rescue, and genetic recombination in phage T4 following x-ray inactivation.

Abstract The survival of phage T4 exposed to soft X-rays in an early intracellular stage is an exponential dose-function, with a slope 1.6 times that of the survival curve for free phage. This difference has also been found with T2 and T6, but not with T3. The gamma-ray survival of T4 is identical for intracellular and extracellular phage. It is concluded that the higher survival of free phage treated with soft X-rays is due to the geometry of the target and the close spacing of the ionizations, which result in bunching of lethal hits. Multiplicity reactivation of T4 under conditions of intracellular X-irradiation is about as extensive as for UV-irradiated T4, the log of the multicomplex survival versus the dose becoming linear at high doses, with a slope of about 0.25 that of the monocomplex survival function. Very little multiplicity reactivation occurs in extracellularly X-ray inactivated T4. Cross-reactivation of markers of intracellularly X-rayed T4 is as high as that of UV-irradiated T4, whereas it is considerably lower with extracellularly X-rayed phage. The frequency of genetic recombination increases as a result of intracellular X-irradiation, but decreases with extracellularly X-rayed phages. All these differences observed with intracellular and extracellular phages can be explained by the hypothesis that the DNA of X-ray inactivated phages has a decreased probability to complete an early step of infection. The dose function of this probability has been roughly estimated from the results of cross reactivation experiments. The similarity of the extent of multiplicity reactivation after UV and after intracellular X-ray inactivation supports the hypothesis of a recombination mechanism.
Current wind tunnel capability and planned improvements at the NASA Langley Research Center

NASA Langley's major wing wind tunnels and the projected facilities planned to be completed by 1988 are presented. Special capabilities, uses, and the improvements done during the Langley's tunnel revitalization program are described for the following facilities: (1) the 30 x 60-ft subsonic tunnel, (2) the 4 x 7-m low-speed testing tunnel, (3) the Low-Turbulence Tunnel, (4) the Spin Tunnel, (5) the National Transonic Pressure Tunnel, (6) Transonic Cryogenic Tunnel, (7) the National Transonic Facility, (8) the 16-ft Transonic Tunnel, (9) the Transonic Dynamic Tunnel, (10) the Unitary Plan Wind Tunnel, and (11) a new 20-inch supersonic wind tunnel which is currently undergoing final checkout. The design concept of an extremely-low disturbance level supersonic tunnel, the upgrading plans for the hypersonic aerothermal complex, and the present and planned capabilities for testing the hydrogen-fueled Scramjet engines are also presented. In addition, uses of inexpensive simple-to-operate research wind tunnels are discussed. Tunnel diagrams and graphs of upgrade results are included.
Learning to Work in Teams

The concept of design as interdisciplinary collaboration is an easy sell. Putting it into practice is another matter. A diverse group of people can simultaneously work on the same problem, but that can be quite different from working together. In a university setting, Christopher Vice shares the tactics and strategies he finds stimulate creative options and nurture the cooperative development and implementation of outcomes.
Seismic design and performance evaluation of steel-frame buildings designed using the 2005 National building code of Canada

The seismic design provisions in the current edition of the National building code of Canada significantly differ from those in the earlier version of the code . Although the code has moved from th...
Percolative versus homogenous energy transport kinetics: time-resolved donor and acceptor fluoresence of isotopic mixed naphthalene crystals

Abstract Tune-resolved spectral studies of the singlet exciton transport threshold in doped naphthalene-perdeuteronaphthalene mixed crystals are presented. While a homogeneous kinetic model adequately explains many of the results, some strong deviations from its predictions are found. These are attributed to clusterization effects.
Rolling KCl Fiber - A Feasibility Study

Using the technique of rolling, KCl single crystals were reduced to round polycrystalline fibers with surfaces which duplicate the surface of the rolls. Crystals were rolled at 300°C to 1.5 mm diameter for a reduction in area of 90%. Due to the imperfections in the cast iron rolls, the fiber surface that was duplicated was of only fair quality. This led to the design of improved rolls with polished surfaces.
A Needs Analysis of an Expanding Hospitality Market—Asian Students

A study of Asian hospitality students was undertaken to determine why they came for an American education, how they heard about the program, and what support services they needed. The study revealed that academic reputation of both the university and the program are important, as are academic facilities, course variety, and other variables. Services desired were tutors, scholarships, matched peer advisors, home newspapers, and helpful faculty advisors.
Expanding the applications of holographic interferometry to the quantitative visualization of oscillatory thermofluid processes using temperature as tracer

In this paper we discuss a novel application of holographic interferometry in the simultaneous quantitative visualization of high-speed, oscillatory flow and temperature fields in complex flow geometries. We consider cases of (i) self-sustained oscillatory flows with main flow imposed in grooved and communicating channels as well as (ii) oscillating thermofluid processes with zero mean velocity in a thermoacoustic refrigerator model. Examples showing unsteady temperature distributions obtained by real-time holographic interferometry combined with high-speed cinematography illustrate the possibilities of the approach introduced in the paper. Our study shows that temperature distributions accurately mirror flow structures in certain types of complex, unsteady flows, thus allowing, apart from the measurement of temperature profiles and heat transfer, also the measurement of oscillatory amplitudes, frequencies, wavelengths as well as the speed of propagation of traveling waves by applying digital image processing techniques. In the grooved and communicating channels it is possible to visualize the structure of the Tollmien–Schlichting waves through isotherms by using the infinite fringe field alignment of holographic interferometry. In the thermoacoustic refrigerator model, small amplitude temperature oscillations generated by the acoustic standing wave are visualized and measured. Image processing as well as data reduction procedures used in the analysis of these flow fields are discussed in the paper. Experimental data obtained by applying the techniques introduced in the paper show good agreement with theory and results of numerical simulations. Our study suggests that using temperature as tracer offers numerous advantages in the study of certain types of complex, unsteady flows.
The evolving role of surgery for advanced renal cell carcinoma in the era of molecular targeted therapy.

Purpose: Thoughtful integration of surgical and medical approaches to metastatic renal cell carcinoma is paramount for maximizing disease control. Accomplishing this in the current era of targeted molecular therapies presents unique challenges and opportunities.Materials and Methods: A systematic review of the MEDLINE® and PubMed® databases, and relevant urological and oncological journals was performed pertaining to cytoreductive nephrectomy, metastasectomy, targeted molecular therapies for renal cell carcinoma, and neoadjuvant and adjuvant approaches to the management of advanced renal cell carcinoma.Results: Cytoreductive nephrectomy provides an overall survival advantage in select patients with metastatic renal cell carcinoma who receive subsequent interferon-α. However, cytokine therapies are now being supplanted by targeted molecular approaches that block the effects of vascular endothelial growth factor and other molecular events. Although cytoreductive nephrectomy remains a standard of care, limit...
A combined oral contraceptive containing 30 mcg ethinyl estradiol and 3.0 mg drospirenone does not impair endothelium-dependent vasodilation.

Abstract Background Ethinyl estradiol (EE) increases endothelium-dependent vasodilation in young women, but certain progestins paired with EE in combination oral contraceptive pills (OCPs) have been shown to antagonize the vasodilatory effects of EE. Therefore, the purpose of this study was to investigate how endothelial function, serum biomarkers and resting blood pressures change across an OCP cycle in women using a monophasic OCP formulation containing the progestin drospirenone. Study Design Twelve women were studied during two hormone phases of their OCP cycle: once at the end of 3 weeks of active pills (30 mcg EE and 3.0 mg drospirenone) and once at the end of a week of placebo pills (no exogenous hormones) Results Endothelium-dependent vasodilation was greater during the active phase compared to the placebo phase (p Conclusion These data suggest that the combination of 30 mcg EE and 3.0 mg drospirenone used in the active phase of this OCP increases endothelium-dependent vasodilation compared to a placebo phase.
Sessions 3 and 8: Pretreatment and Biomass Recalcitrance: Fundamentals and Progress

Overcoming lignocellulosic biomass recalcitrance followed by enzymatic hydrolysis of structural polymeric carbohydrates (i.e., cost-efficient liberation of fermentable sugars) is perhaps the most challenging technical and economic barrier to success of biorefineries [1–3]. Lignocellulosic biomass is a natural composite having three main biopolymers (cellulose, hemicellulose, and lignin) intertwined chemically and physically. The central role of biomass pretreatment has been indicated by the fact that 12 oral presentations and 76 posters were given on the subject at this symposium. Pretreatment is among the most costly steps in biochemical conversion of biomass [4, 5], accounting for up to 40% of the total processing cost [6]. Also, it affects the costs of other operations including size reduction prior to pretreatment and enzymatic hydrolysis and fermentation after pretreatment. Pretreatment can also strongly influence downstream costs involving detoxification if inhibitors were generated, enzymatic hydrolysis rate and enzyme loading, mixing power, product concentration, product purification, power generation, waste treatment demands, and other process variables [4]. Although a number of pretreatment methods have been proposed and investigated on the laboratory scale and even pilot plant scale during the past several decades, much of the data in the literature have been obtained and reported under different standards, leading to confusion on the part of academic researchers and potential industrial investors alike. In order to address and resolve this confusion, Prof. Bruce Dale of Michigan State University gave a brief opening to both sessions entitled “Raising the Bar for Pretreatment Research.” Since overall sugar yields are one of the most important factors for the evaluation of Appl Biochem Biotechnol (2009) 153:80–83 DOI 10.1007/s12010-009-8610-3
In vitro phosphorylation of bovine adrenal chromaffin cell tyrosine hydroxylase by endogenous protein kinases.

: Under phosphorylating conditions, addition of Ca2+ or cyclic AMP to the 100,000 g supernatant of purified bovine adrenal chromaffin cells increases both the incorporation of 32P into tyrosine hydroxylase and the activity of the enzyme. Combining maximally effective concentrations of each of these stimulating agents produces an additive increase in both the level of 32P incorporation into tyrosine hydroxylase and the degree of activation of the enzyme. The increased phosphorylation by Ca2+ is due to stimulation of endogenous Ca2+-dependent protein kinase activity and not inhibition of phosphoprotein phosphatases. When the chromaffin cell supernatant is subjected to diethylaminoethyl (DEAE) chromatography to remove calmodulin and phospholipids, tyrosine hydroxylase is no longer phosphorylated or activated by Ca2+; on the other hand, phosphorylation and activation of tyrosine hydroxylase by cyclic AMP are not affected. Subsequent replacement of either Ca2+ plus calmodulin or Ca2+ plus phosphatidylserine to the DEAE-fractionated cell supernatant restores the phosphorylation, but not activation of the enzyme. Reverse-phase HPLC peptide mapping of tryptic digests of tyrosine hydroxylase from the 100,000 g supernatant shows that the Ca2+-dependent phosphorylation occurs on three phosphopeptides, whereas the cyclic AMP-dependent phosphorylation occurs on one of these peptides. In the DEAE preparation, either cyclic AMP alone or Ca2+ in the presence of phosphatidylserine stimulates the phosphorylation of only a single phosphopeptide peak, the same peptide phosphorylated by cyclic AMP in the crude supernatant. In contrast, Ca2+ in the presence of calmodulin stimulates the phosphorylation of three peptides having reverse-phase HPLC retention times that are identical to peptides phosphorylated by Ca2+ addition to the crude unfractionated 100,000 g supernatant. Rechromatography of the peaks from each of the in vitro phosphorylations, either in combination with each other or in combination with each of the seven peaks generated from phosphorylation of tyrosine hydroxylase in situ, established that cyclic AMP, Ca2+/phosphatidylserine, and Ca2+/calmodulin all stimulate the phosphorylation of the same reverse-phase HPLC peptide: in situ peptide 6. Ca2+/calmodulin stimulates the phosphorylation of in situ peptides 3 and 5 as well. Thus, tyrosine hydroxylase can be phosphorylated in vitro by protein kinases endogenous to the chromaffin cell. Phosphorylation occurs on a maximum of three of the seven in situ phosphorylated sites, and all three of these sites can be phosphorylated by a Ca2+/calmodulin-dependent protein kinase.
Slow IPSC kinetics, low levels of α1 subunit expression and paired‐pulse depression are distinct properties of neonatal inhibitory GABAergic synaptic connections in the mouse superior colliculus

Remodelling of visual maps in the superior colliculus (SC) depends on neuronal activity. Synaptic inhibition could contribute to this process because spontaneous spike discharge in the SC was modulated by GABA(A) receptor activation at postnatal days (P) 1-3. To investigate the functional capacity of GABAergic synaptic transmission at this early stage of development, whole-cell patch-clamp recordings were made from wide field neurons (WFNs) in horizontal slices comprising the superficial grey layer of the SC. Focal stimulation in the vicinity of WFNs evoked tetrodotoxin-sensitive stimulus-locked inhibitory postsynaptic currents (eIPSCs). The failure rate of eIPSCs was low ( approximately 0.2), and the maximal amplitude of evoked unitary eIPSCs exceeded the amplitude of average miniature IPSCs (mIPSCs) by a factor of 4-5, suggesting that action potential-mediated GABA release was more effective than spontaneous release. Some of the properties of GABAergic synaptic transmission in the neonatal SC were age-specific. In contrast with eIPSCs in the more mature SC at P20-22, neonatal eIPSCs decayed more slowly, preferentially fluctuated in duration, not amplitude, and mostly lacked temporal summation, due to depression at shorter intervals. The paired-pulse ratio (eIPSC2 : eIPSC1) was inversely related to the duration of eIPSCs. PCR analysis showed, in addition, that the ratio of alpha1 : alpha3 subunit expression was lower in the neonatal SC. Together, these results suggest that, at a young age, efficacy of GABAergic synaptic transmission is primarily constrained by the slow kinetics and the saturation of postsynaptic GABA(A) receptors.
The possible activity of large and small jaw muscle units in experimental tooth clenching in man.

Summary Eight human subjects exercised maximum voluntary tooth clenching until there was complete exhaustion of the contracting jaw muscles (isometric endurance time). During the isometric muscle contractions the myoelectrical currents of the masseter and anterior temporalis muscle were sampled by bipolar surface electrodes, integrated, and cumulatively stored. The myoelectrical activity was studied at recording thresholds of 1 μV and 40 μV, i.e. all action potentials below threshold level were ignored. The observations suggested that the number of fast glycolytic and fast oxidative glycolytic motor units in the masseter muscle might have exceeded that in the anterior temporalis muscle; and/or the size of the masseter muscle units might have been larger than that of the anterior temporalis muscle units.
Making lemonade: exploring the bright side of large lecture classes

Pedagogy of large lecture classes has traditionally focussed on deemphasizing the problems their size creates. This approach has yielded valuable practical advice for instructors. However, this paper argues that there are pedagogical advantages to the large lecture format and that exploiting these advantages can further improve classroom instruction. I present some advantages of large classes and anecdotes that demonstrate how to exploit these advantages.
Theory and design of electronic relays

A unified theory on the principles and characterizations of electronic relays is presented. A basic realization scheme is shown to consist of a cascade connection of an isolation box, an analog-to-binary converter, and an electronic switch. A total of eight canonic realizations are given for synthesizing each of the four types of electronic relays. In conclusion the design of two complete practical electronic relays is presented and the actual performance is verified through experimental measurements.
Detrusorrhaphy for repair of unilateral vesicoureteral reflux: report of 76 patients using a modified technique

Abstract Objective. To present our results for repair of unilateral vesicoureteral reflux in 76 children using a modified technique of detrusorrhaphy. Methods. A retrospective chart review was performed for 76 children who underwent repair of unilateral vesicoureteral reflux by a modified technique of detrusorrhaphy. Of the 76 refluxing ureters, 12 were associated with historically refluxing contralateral ureters. In addition, 72/76 were grades II to IV; 4/76 grade V; three had a paraureteral diverticulum; four completely duplicated collecting systems; and two had associated ureteroceles. The surgical technique was modified to preserve both the obliterated umbilical artery and superior vesical pedicle and to minimize trigonal distortion through dissection lateral to the trigone in a direct path to the bladder neck. Results. Seventy-five of 76 ureters were successfully repaired (99%). The remaining ureter showed initial improvement to grade I reflux and spontaneous resolution by 1 year. Obstruction did not occur. Three episodes of "new onset" contralateral vesicoureteral reflux were noted postoperatively. This represents a substantial decrease in incidence (3.9%) when compared with previously reported series (18%). Conclusion. Detrusorrhaphy is a reasonable treatment of unilateral vesicoureteral reflux with utility in the full range of anatomic associations. This approach is also associated with a lower incidence of new onset, contralateral reflux when compared with intravesical surgery.
Towards a critical interdisciplinarity? African history and the reconstruction of universal narratives

This article examines the question of whether interdisciplinary research has the potential of radically transforming current understandings of the historical discipline by looking at the case of African historiography. It starts by explaining current debates about the nature of history by looking at the arguments of reconstructionist, constructionist and deconstructionist historians. It acknowledges that the majority of Africanist historians subscribe to a practical-realist position and explores whether their interdisciplinary work challenges or endorses this perspective. After making a distinction between critical and instrumental interdisciplinarities, the article goes on to examine the collaborations between historians and archaeologists, linguists and anthropologists. These experiences demonstrate that Africanist interdisciplinarity can be characterized as instrumental since it has not effected radical change in the definition of the discipline. However, Africanists' interdisciplinary experiences do h...
Towards Thinner Theologies: Hick and Alston on Religious Diversity

Western Christianity has never been ignorant of religious diversity. Early Christianity had to make its way in the religiously pluralistic environment of late antiquity. During the medieval period, Islam put cultural and military pressure on European Christendom. And religious diversity has often been seen by Christians as an intellectual challenge to which a response must be made. Origen wrote contra Celsum to defend Christianity against pagan critique. Thomas Aquinas wrote contra gentiles to make the case for the rationality of Christian belief. So Western Christianity has never been without a philosophical problem of religious diversity of some sort.
Teaching feedback to first-year medical students: long-term skill retention and accuracy of student self-assessment.

BACKGROUND Giving and receiving feedback are critical skills and should be taught early in the process of medical education, yet few studies discuss the effect of feedback curricula for first-year medical students.
Sarcoplasmic Reticulum Ca2+ Release in Rat Slow- and Fast-Twitch Muscles

The same isoform of ryanodine receptor (RYR1) is expressed in both fast and slow mammalian skeletal muscles. However, differences in contractile activation and calcium release kinetics in intact and skinned fibers have been reported. In this work, intracellular Ca2+ transients were measured in soleus and extensor digitorum longus (EDL) single muscle fibers using mag-fura-2 (K D for Ca2+= 49 μm) as Ca2+ fluorescent indicator. Fibers were voltage-clamped at V h =−90 mV and sarcoplasmic reticulum calcium release was measured at the peak (a) and at the end (b) of 200 msec pulses at +10 mV. Values of a-b and b were assumed to correspond to Ca2+-gated and voltage-gated Ca2+ release, respectively. Ratios (b/a-b) in soleus and EDL fibers were 0.41 ± 0.05 and 1.01 ± 0.13 (n= 12), respectively. This result suggested that the proportion of dihydropyridine receptor (DHPR)-linked and unlinked RYRs is different in soleus and EDL muscle. The number of DHPR and RYR were determined by measuring high-affinity [3H]PN200-110 and [3H]ryanodine binding in soleus and EDL rat muscle homogenates. The B max values corresponded to a PN200-110/ryanodine binding ratio of 0.34 ± 0.05 and 0.92 ± 0.11 for soleus and EDL muscles (n= 4–8), respectively. These data suggest that soleus muscle has a larger calcium-gated calcium release component and a larger proportion of DHPR-unlinked RYRs.
The effect of 15-Lipoxygenase-1 expression on cancer cells

Lipoxygenases oxidatively metabolize polyunsaturated fatty acids to a rich spectrum of biologically active products. One enzyme of the lipoxygenase family, Arachidonate 15-lipoxygenase-1 (arachidonate:oxygen 15-oxidoreductase, EC 1.13.11.33) [15-LO-1], is implicated in several forms of epithelial cell cancers, and provides a rationale for exploring its role in the progression and metastasis of cancers. Thus, 15-LO-1 could be a marker of the growth and spread of cancers. The importance of 15-LO-1 expression is imparted by its metabolic product of linoleic acid, yielding 13-(S)-hydroxyoctadecadienoic acid (13-(S)-HODE). In order to maximize our understanding of the roles of lipoxygenases and cyclooxygenases in cancer, it is necessary to correlate their metabolic pathways to the respective expression levels, and not exaggerate the presence or absence of an enzyme or its function when it clearly is not there. It is also important to acknowledge that some forms of these enzymes may not even be relevant to human disease. Although it is unlikely that any single gene is sufficient to account for the complex etiology of cancer, 15-LO-1 overexpression is clearly a key component in the cell proliferation process. This article is divided into three sections emphasizing the key role of 15-LO-1 in prostate, colorectal, and breast cancers.
Iron catalyzed cross-coupling reactions. Synthesis of arylethenes.

Abstract Iron (III) complexes have been found to effectively catalyze the coupling of alkenyl halides with aryl Grignard reagents to provide arylethenes in excellent yields.
The Timing of Investments in Human Capital: A Case in Education

The timing of investments in human capital is important. Since the net present value of an investment in human capital may change over time, the decision to invest should be made so as to maximize the net present value of the investment. After sketching the proper decision rule in cases where timing is important in an investment, the net present value of completing eighth grade rises for nonwhites in the South. This finding suggests that it might sometimes be wise to delay investments in education until the students are older.
Properties and Applications of a Class of Polynomials

Abstract A study of cellular arrays have led us to examine the Fibonacci polynomial and a tree enumeration polynomial Fn(x) and Tn(m), respectively. Tn(m) is for linear iterative cellular arrays of n cells with a common edge between adjacent m-cycle cells. The coefficients of Tn(m) have the same absolute value as those of Fn(x) but alternating signs. The zeros of these monic polynomials are shown to be real with -2⩽mi⩽2, and imaginary with xi⩽¦2¦. The number of spanning trees or “complexity” of these cellular arrays is also shown to be given by a generalization of Sedlacek's expression for the case of m = 4, n = 0, 1,2,....
The transient solution of time-dependent M/M/1 queues

The transient behavior of time-dependent M/M/1 queues is studied. The boundary probability function pi /sub 0/(t), which is the probability that the queue is empty at time t, is shown with analyticity arguments to satisfy a Volterra-type integral equation. The boundary integral equation is derived, and a numerical algorithm is used to solve the integral equation and to find the expected queue size from pi /sub 0/(t). The approach can be applied to many other types of time-dependent queues. Examples are given. >
Synthesis of Functionalized Organic Second-Order Nonlinear Optical Chromophores for Electrooptic Applications

The design and syntheses of functionalized second-order nonlinear optical chromophores, suitable for covalent incorporation into functionalized high-performance polymers, are described. The chromophores with hydroxy alkyl functionality have diarylamino groups as the donor moiety and a styryl thiophene moiety as the conjugated bridge. The triarylamine parts of the molecules were synthesized using palladium-catalyzed C−N bond forming reactions. The conjugated bridge was assembled using the Wittig reaction. The acceptor groups were installed in the last steps of the syntheses.
Perturbation theory for the two-dimensional polaron in a magnetic field

The ground-state energy of a two-dimensional polaron in a magnetic field is evaluated in fourth-order perturbation theory by a novel method. In this method complicated sums over products of matrix elements and energy denominators are replaced by simple algebraic manipulations of operators. An analytical expression is derived for the high-magnetic-field limit; in that limit the sixth-order perturbation contribution is also determined.
The Effect of Labor Force Participation on Female Suicide Rates: An Analysis of Individual Data from 16 States

Previous American-based research on the effect of womens' labor force participation (WPLF) on suicide has been based on highly aggregated data which makes it difficult to determine the actual, individual level suicide rate of employed versus unemployed women. The present study employs recent data which allow for the calculation of such individual-level suicide rates. Controls are incorporated for age and marital status. The results indicate that the suicide rates for employed, younger women are consistently lower than the suicide rates of women who are unemployed. The same tends to be true of middle-aged women. For elderly women, however, the relationship reverses with WPLF being associated with relatively high suicide rates. The findings on young and middle-aged women support a role accumulation model of WPLF, while the findings on elderly women support the theory of status integration.
Investigation of the tip clearance flow inside and at the exit of a compressor rotor passage-part II: turbulence properties

The flow in the tip clearance region of a compressor rotor is highly turbulent due to the strong interaction of the leakage flow with the annulus wall boundary layer. This paper deals with the turbulence properties of the flow in the tip clearance region of a moderately loaded compressor rotor. The experimental results reported in this paper were obtained using a two-sensor hot-wire probe in combination with an ensemble averaging technique. Blade-to-blade distribution of the axial and tangential turbulence intensities at various radial locations and ten axial locations (four inside the blade passage and the remaining six outside the passage) were derived from this data. Isointensity contours in the clearance region at various radial locations were also obtained from the experimental data. A region of very high turbulence intensities was indicated at the half-chord location from these results. The turbulence intensity profiles also indicated that the leakage flow travels toward the midpassage before rolling up. The turbulence is almost isotropic beyond three-quarter chord downstream of the trailing edge.
The calcium channel blocker controversy.

A major controversy about the safety of calcium channel blockers (CCBs) has arisen since the publication of a case-control study showing that hypertensives who suffered an acute myocardial infarction (MI) were more likely than hypertensives who had not had an MI to be taking one of these (short-acting) agents than other antihypertensive agents. This study was accompanied by a republication of older studies showing that large doses of short-acting nifedipine given to post-MI patients increased their mortality rate. The danger of massive doses of short-acting nifedipine in a post-MI patient is real but irrelevant to current practice. On the other hand, the putative dangers of short-acting CCBs in the treatment of hypertension do not apply to the current use of long-acting CCBs. Therefore the scare over their use is both irrational and unfortunate. (Hypertens Res 1996; 19: 57-64)
The fine structure of an absorptive epithelium in a viviparous teleost.

Embryos of the viviparous teleost, “Characodon” eiseni, have unusual anal processes that function only during gestation and are lost shortly after birth. This study was undertaken to determine if the fine structure of the process epithelium supports the assumption that these cells have an absorptive function. The process epithelium is a single layer of columnar cells. At peak activity intercellular spaces become very large and isolate individual cells which simultaneously lose much of their cell mass. The cells are characterized by microvilli on their free surface, much pinocytic activity and by the formation of at least four different kinds of vesicles. There is much evidence that these vesicles fuse together. A distinctive characteristic of these cells is a system of tubules and flattened cisternae that somewhat resemble the endoplasmic reticulum yet they differ from it in several respects. It is suggested these profiles aid in fragmenting the cell at periods of peak absorptive activity, thereby increasing the cell surface. Possible mechanisms of food absorption are considered. The fine structure of these cells supports the contention that these embryonic processes serve as absorptive organs during gestation.