cssi/SciSciGPT-SciSciNet huggingface dataset:
Three-dimensional finite element analysis using crystal plasticity for a parameter study of microstructurally small fatigue crack growth in a AA7075 aluminum alloy

Abstract Three-dimensional finite element analysis using a crystal plasticity constitutive theory was performed to understand and quantify various parametric effects on microstructurally small fatigue crack growth in a AA7075 aluminum alloy. Plasticity-induced crack opening stresses (So/Smax) were computed, and from these results the crack propagation life N was obtained. A design of experiments (DOE) technique was used to study the influences of seven parameters (maximum load, load ratio, particle modulus, the number of initially active slip systems, misorientation angle, particle aspect ratio, and the normalized particle size) on fatigue crack growth. The simulations clearly showed that the load ratio is the most influential parameter on crack growth. The next most influential parameters are maximum load and the number of initially active slip systems. The particle modulus, misorientation angle, particle aspect ratio, and the normalized particle size showed less influence on crack growth. Another important discovery in this study revealed that the particles were more important than the grain boundaries for inducing resistance for microstructurally small fatigue crack growth.
Conservation tillage for soybean in the U.S. Southeastern Coastal Plain

Double cropping of soybean has progressed less rapidly in the U.S. Southeastern Coastal Plains than expected by the ample rainfall and long frost-free season. Post-emergence herbicides, the management of plant residues to reduce water use by cover crops, and a no-till planter with a combination subsoiler are the innovations that have facilitated this new production. Full-season soybean (Glycine max L.) was planted following a grazed cover crop of winter rye (Secale cereale L.) or late-season soybean was planted following winter wheat harvest. In both cases, a special planter was used with an integral subsoil shank ahead of the opener. Full-season soybean under conservation tillage produced yields equal to or better than yields in conventional clean tillage. In a dry summer, soybean yields under conservation tillage exceeded conventional tillage because of suppressed early biomass production which conserved stored soil water and favored growth during the reproduction phase of the crop-cycle. Late-season soybean yields behind wheat favored the conservation tillage practice of in-row subsoil-planting into stubble. However, planting in burned-off wheat stubble produced the highest yields in this study. In a dry spring, the cover crop accelerated soil water use which resulted in lower soybean yields under conservation tillage. Comparisons of 76 vs. 97 cm row spacing were inconclusive, but the trend suggests that wider rows conserve water under periods of drought and that the narrower-row configuration favors adequate water regimes.
Effects on labeling index as a predictor of response to chemotherapy in the 13762 adenocarcinoma.

A series of 24 experiments was carried out, in which treatment effect was determined in vivo on rats bearing measurable implants, of 13762 adenocarcinoma treated with a variety of chemotherapeutic agents, alone or in combination. In 11 experiments, a reduction in mean tumor are was observed after treatment (response) while 13 showed no such effect (no response).
Critical Stresses for Extension of Filament‐Bridged Matrix Cracks in Ceramic‐Matrix Composites: An Assessment with a Model Composite with Tailored Interfaces

Matrix cracking was studied in a model unidirectional composite of SiC filaments in an epoxy-bonded alumina matrix. The residual clamping stress on the filaments due to the shrinkage of the epoxy was moderated with the addition of the alumina filler, and the filament surface was coated with a releasing agent to produce unbonded frictional interfaces. Uniaxial tension specimens with controlled through-cracks with bridging filaments were fabricated by a two-step casting technique. Critical stresses for extension of the filament-bridged cracks of various lengths were measured in uniaxial tension using a high-sensitivity extensometer. The measured crack-length dependence of the critical stress was in good agreement with the prediction of a stress-intensity analysis that employed a new force-displacement law for the bridging filaments. The analysis required independent experimental evaluation of the matrix fracture toughness, the interfacial sliding friction stress, and the residual tension in the matrix. The matrix-cracking stress for the test specimens without the deliberately introduced cracks was significantly higher than the steady-state cracking stress measured for the long, filament-bridged cracks.
Liquefaction of starch by a single-screw extruder and post-extrusion static-mixer reactor☆

Abstract The production of ethanol has increased rapidly during the past few years, especially since enactment of the 1990 Clean Air Act. Production costs, however, are high, requiring improved conversion technologies. The gelatinization of starch with conventional jet cookers requires a minimum moisture content of 65% by weight. An alternative to jet cookers is extrusion, which requires significantly less moisture to gelatinize starch. Starch gelatinization and liquefaction was achieved using single-screw extrusion and a post-extrusion static-mixer reactor. The effects of moisture content, reactor temperature, reactor length, and enzyme concentration on liquefaction were evaluated using response surface methodology. The use of a static-mixer reactor tube improved mixing of the gelatinized slurry and increased residence times, resulting in increased starch degradation and reduced viscosity. Comparison of costs for extrusion and conventional technology indicates extrusion has potential as a cost-effective alternative.
Thin silicon waveguides for biological and chemical sensing

We show that thin silicon-on-insulator (SOI) microphotonic waveguides offer significant advantages over other material platforms for the applications of biological and chemical sensing. The high index contrast inherent to SOI waveguides allow an extremely large yet highly localized electric field to be supported in the evanescent tail of the waveguide mode, ideal for the probing of thin biological layers. Various sensing geometries including Mach-Zehnder interferometers and high quality factor ring resonators have been designed and fabricated and their performance is presented. SOI sensors are shown to be capable of providing higher intrinsic sensitivity over comparable sensor designs reported in all other lower index contrast planar waveguide material systems. Finally, the device design conditions for optimized sensitivity are examined for the sensing of both bulk solutions and thin adsorbed biomolecular layers.
Undergraduates' evaluations of assigned search topics

This paper evaluates undergraduate students' knowledge, interests and experiences with 20 topics from the TREC Robust Track collection. The goal is to characterize these topics along several dimensions to help researchers make more informed decisions about which topics are most appropriate to use in experimental IIR evaluations with undergraduate student subjects.
Saturn’s Northern Hemisphere Ribbon: Simulations and Comparison with the Meandering Gulf Stream

Voyager observations of Saturn in 1980–81 discovered a wavy feature engirdling the planet at 47°N planetographic latitude. Its latitude coincides with that of an eastward jet stream, which is the second fastest on Saturn after the equatorial jet. The 47°N jet’s wavy morphology is unique among the known atmospheric jets on the gas giant planets. Since the Voyagers, it has been seen in every high-resolution image of this latitude for over 25 years and has been termed the Ribbon. The Ribbon has been interpreted as a dynamic instability in the jet stream. This study tests this interpretation and uses forward modeling to explore the observed zonal wind profile’s stability properties. Unforced, initial-value numerical experiments are performed to examine the nonlinear evolution of the jet stream. Parameter variations show that an instability occurs when the 47°N jet causes reversals in the potential vorticity (PV) gradient, which constitutes a violation of the Charney–Stern stability criterion. After the initial instability development, the simulations demonstrate that the instability’s amplitude nonlinearly saturates to a constant when the eddy generation by the instability is balanced by the destruction of the eddies. When the instability saturates, the zonal wind profile approaches neutral stability according to Arnol’d’s second criterion, and the jet’s path meanders in a Ribbon-like manner. It is demonstrated that the meandering of the 47°N jet occurs over a range of tropospheric static stability and background wind speed. The results here show that a nonlinearly saturated shear instability in the 47°N jet is a viable mechanism to produce the Ribbon morphology. Observations do not yet have the temporal coverage to confirm the creation and destruction of eddies, but these simulations predict that this is actively occurring in the Ribbon region. Similarities exist between the behaviors found in this model and the dynamics of PV fronts studied in the context of meandering western boundary currents in Earth’s oceans. In addition, the simulations capture the nonlinear aspects of a new feature discovered by the Cassini Visual and Infrared Mapping Spectrometer (VIMS), the String of Pearls, which resides in the equatorward tip of the 47°N jet. The Explicit Planetary Isentropic Coordinate (EPIC) model is used herein.
Measurement of 2-amino-1-methyl-6-phenylimidazo(4,5- b )pyridine (PhIP) in acid-hydrolyzed urine by high-performance liquid chromatography with fluorescence detection

Heterocyclic aromatic amines are carcinogenic combustion products formed during the cooking of meat at moderate to high temperatures. The authors have developed a simplified method to measure the commonly formed heterocyclic amine, 2-amino-1-methyl-6-phenylimidazo(4,5-b)pyridine (PhIP), in acid-hydrolyzed human urine by HPLC with fluorescence detection after immuno-affinity chromatography, The method was compared with a previously validated method using gas chromatography/mass spectrometry after chemical derivatization. The comparison was performed using 100 urine samples from a study of 10 subjects before, during and after ingesting identical amounts of charbroiled (grilled) meat on 5 consecutive days. The overall correlation between the two assays was r = 0.87 (p < 0.0001). The HPLC method was then used to measure PhIP in acid-hydrolyzed urine collected from 66 subjects participating in a study of fried meat ingestion. Fried meat cooked at high temperature was fed to subjects based on body weight; urines were collected before feeding and 0-12 and 12-24 h after feeding. In a subset of six subjects, urinary PhIP concentration was 3-13-fold higher in the 0-12-h urine than in the 12-24-h urine. In the total study population, a significant correlation (r = 0.61, p < 0.0001) between the amount of fried meat ingested and urinary PhIP was observed. These results indicate that measurement of urinary PhIP by HPLC after immuno-affinity chromatography is a useful alternative to mass spectrometry methods for assessing recent exposure in subjects ingesting moderate to high levels of PhIP.
IN-SITU MEASUREMENT OF STIFFNESS PROFILES IN OCEAN BOTTOM MATERIALS USING THE SASW METHOD

The Spectral Analysis of Surface Waves (SASW) method is a nonintrusive seismic method which has been used successfully on land to determine shear modulus profiles of geotechnical sites. Application of the SASW method offshore is being investigated both analytically and experimentally. Of particular interest is the possibility of detecting the presence of gas hydrates within about the upper 200ft of the seafloor by distinct changes in the shear stiffness profile. Initial studies show the potential usefulness of the method, particularly in deep water.
Normal and more highly reactive horses. I. Heart rate, respiration rate and behavioral observations

Thirty-two Quarter horse yearlings were utilized in a split-plot experiment to establish behavioral tendencies for two levels of emotionality; normal and a more highly reactive level of emotionality termed nervous. Four observers who were experienced with horses scored the yearlings on an emotionality scale from 1 to 4, with 1 representing the highly nervous yearlings and 4 representing the quiet yearlings. Emotionality evaluations were based upon the response of the yearlings to a standard regimen of standing in a chute, being identified and being released from the chute. The inter-rater reliability coefficients were 0.90 for the normal yearlings and 0.65 for the nervous yearlings, indicating that the raters agreed less when evaluating the nervous yearlings. Yearling heart rates in the chute were correlated (r = −0.54, P<0.002) with the average emotionality score. Observational data on behavior collected 2 days following the emotionality scoring procedure indicated that the normal yearlings maintained a greater (P<0.001) individual distance than the nervous yearlings. From an activity summary, the normal yearlings spent 10.9% of the time lying down (LD), 79.1% standing (S), 9.6% walking or trotting (WT) and 0.4% of the time cantering or galloping (CG). The nervous yearlings spent 5.7% of the observational periods LD, 79.2% S, 11.7% WT and 3.4% CG. The nervous yearlings tended to have a higher overall activity index level than did the normal yearlings. Results indicate horses of different emotionality levels exhibited different behavioral patterns.
The electronic spectra of the isomers of reduced 1-alkyl-nicotinamide

Abstract A self-consistent field molecular orbital calculation has been performed on the three isomers of reduced N -alkyl-nicotinamide. The calculated excited states show reasonably good agreement with experiment. The first excited state is one in which electrons leave the ring nitrogen but do not greatly increase the electron density of the amide oxygen as is generally assumed. The calculated π-dipole moments for the ground and first excited states of the transoid 1,4-isomer are in excellent agreement with the total experimental moments. The calculated electron densities of the ring carbon atoms in the 1,4-isomer also are in agreement with observed NMR chemical shifts.
Effects of Sex and Age on Bone Microstructure at the Ultradistal Radius: A Population-Based Noninvasive In Vivo Assessment

In a population-based cross-sectional study, we examined effects of sex and age on bone microstructure at the wrist using high-resolution 3-D pQCT. Compared with women, men had thicker trabeculae in young adulthood and had less microstructural damage with aging. These findings may contribute to the virtual immunity of men to age-related increases in wrist fractures. Introduction Although changes in bone microstructure contribute to fracture risk independently of BMD, it has not heretofore been possible to assess this noninvasively in population-based studies.
Learning relational algebra by snapping blocks

Relational algebra provides a theoretical foundation for how modern database management systems optimize and execute queries. Its main concepts are based on set theory and first order logic, which can be challenging for students to learn due to their abstract nature. This paper presents Bags, a new type of visual programming environment (inspired by Snap!) for the teaching of relational operations and data analysis. Students formulate algebraic queries by snapping together graphical blocks that represent data sets and relational operators, resulting in an interactive visualization of the underlying concepts. The outcomes of this work will not only enhance university-level database courses, but also provide an engaging computational thinking resource for K-12 teachers in content areas outside of science and engineering.
Retinal topography in the optic tract of adult goldfish.

Abstract The present study was aimed at determining how transformations in fiber order establish a retinal topography in the optic tract of adult Carassius auratus . Horseradish peroxidase was applied to the optic nerve or retina, and the pathways of labeled axons originating from retinal annuli or wedges were analysed in reconstructed serial-sections and wholemounts of the optic pathway. The age-related fiber order of the optic tract involves a rotation of the optic pathway that begins near the chiasm. continues through the optic tract as it wraps around the brain, and extends through the brachia. The relative order of laminae, in which each lamina is composed of age-related axons, is maintained in the optic pathway. The laminae add systematically onto the optic tract in a mediolateral direction with the oldest lamina forming the medial margin. Retinal sector order in the optic tract is established by the rearrangement of axons from each lamina. These rearrangements begin at the chiasm and, in part, involve transposition of axons originating from the ventrotemporal and dorsonasal sectors of the retina. The transformations achieve a fiber order in the optic tract that is appropriate for entry into the tectum. It is proposed that the final retinal topography of the optie tract is determined by the combined influences of selective affinities along the neural axis and substrate guidance mechanisms, the latter being mediated largely by the oldest axons of the fasciculus medialis tractus opticus.
The State and Capitalist Transformation in Sub-Saharan Africa A Development Model

Declining performance of the postcolonial African states suggest the inefficiency of centralization and or socialist strategy that currently dominates the region. The solution, however, is not a return to the largely unrestrained liberal economic models of the 1960s, such as import substitution industrialization or commodity export specialization. Whether from the left or right, the inability of all three models to define precise development roles for Africa state elites suggest their insensitivity to and inadequacy for the needs of these politically dynamic young states of Africa. An alternative model presented in this article would involve state elites in grass roots capitalist development. The model fosters decentralization and economic development without sacrificing rule legitimization and national integration as equal objectives. In many respects, the model is an attempt to adapt to African realities the norms of embedded liberalism that properly describe current Western liberalism.
Communication plays a critical role in web-based monitoring.

Background: Patient–health care practitioner (HCP) interaction via a Web-based diabetes management system may increase patient monitoring of their blood glucose (BG) levels. Methods: A three-center, nonrandomized, prospective feasibility study of 109 Native Americans with poorly controlled type 1 diabetes mellitus and type 2 diabetes mellitus were recruited from Alabama, Idaho, and Arizona. The study intervention included the use of a Web-based diabetes management application (MyCareTeam ® ) that allowed timely interaction between patients and HCPs. Information about diabetes, nutrition, and exercise was also available. Finally, patients were able to provide BG readings to their HCP via the MyCareTeam system. Results: As a result, 59.6% of the patients sent one or more messages to their HCP, 92.67% received one or more messages from their HCP, and 78.89% received one or more person-centered messages from their HCP. Additionally, the number of times a patient logged into the system and the frequency with which they tested their blood sugar were correlated with (a) the number of messages sent to their HCP, (b) the total number of messages received from their HCP, and (c) the number of person-centered messages received from their HCP. Thus patients who sent more messages also tested their BG more frequently, as measured by the number of BG readings uploaded from their meter to the MyCareTeam database. Person-centered messages seem to be particularly important to motivating the patient to monitor their BG levels and use the Web-based system. Conclusions: These results suggest that patient–HCP interaction and, in particular, more personalized interactions increases patient frequency of BG monitoring.
Acute Autonomic Responses to Postural Change, Valsalva Maneuver, and Paced Breathing in Older Type II Diabetic Men

Purpose: To examine the effects of advanced age and diabetes on the response to standard tests of cardiovascular reflexes. Desigin: Group comparison. Setting: Psychophysiology laboratory, Department of Veterans Affairs Medical Center. Patients: Sixteen elderly male (67–81 years old) non-insulin dependent diabetic subjects without hypertension and nine elderly male (63–77 years old) controls. Main Outcome Measures: Continuous (beat-by-beat) measures of heart rate, systolic blood pressure, diastolic blood pressure, and skin conductance were studied during tests of Valsalva maneuver, deep breathing, and postural change from sitting to standing. Results: In comparison with elderly controls, the diabetic patients showed altered cardiovascular responses in measures of heart rate variability during Valsalva and standing. None of the subjects evidenced frank postural hypotension, but there was a greater fall in diastolic blood pressure immediately after standing for the diabetic patients compared with the controls. There was also a significant relationship between this response and decreased heart rate variability during Valsalva. Conclusions: Older type II diabetic patients compared with healthy controls had mild cardiovascular abnormalities. These results parallel those of studies comparing younger diabetics and controls.
Observation of spatial variations in the resonance frequency of an optical resonator

The observation of a dependence of the measured resonance frequency of an optical cavity on the size and position of the detector is reported and attributed to the presence of higher-order transverse modes in the cavity. This effect, which is due to the nonorthogonality of these modes when averaged over a limited aperture or an inhomogeneous detector surface, has been carefully studied. The results of our calculations are in good agreement with experimental observations. Methods of minimizing such frequency-pulling effects are suggested.
Legume nodule organogenesis

Bacteria of the family Rhizobiaceae and leguminous plants have the ability to establish a symbiosis in which the bacteria fix dinitrogen within a novel plant organ, the root nodule. The development of the root nodule involves signal exchange between the bacterial symbionts and their plant hosts. Flavonoids produced by the plant trigger the induction of bacterial nodulation genes that encode proteins involved in production and transport of specific lipochitin signal molecules that initiate nodule organogenesis. Several discoveries regarding the molecular mechanisms of nodule organogenesis have recently been made, with implications for understanding Nod-signal action, and bringing into focus possibilities such as the identification of Nod-signal receptors and investigations into putative conserved lipo-chitin developmental regulators in both legumes and non-legumes.
Pseudoturnor cerebri and pregnancy

Pseudotumor cerebri (PTC) is most commonly seen in obese women of reproductive age. We studied 109 women with PTC between ages 16 and 44 years. In 11, PTC started during pregnancy. Thirteen women with previous diagnosis of PTC, including two of the aforementioned 11, had an additional 17 documented pregnancies. Patients were matched by age and parity with controls. Obstetric complications occurred more frequently in the controls. Visual loss occurred with the same frequency in pregnant and nonpregnant patients. Treatment of PTC patients in pregnancy should be the same as for nonpregnant PTC patients, except that calorie restriction and diuretic use are contraindicated. Obstetric management is no different from that of normal pregnancy.
Hydroxamate siderophore mediated iron uptake in E.coli: Stereospecific recognition of ferric rhodotorulic acid (1)

Ferric ion uptake via the fhuE receptor of E. coli is stereospecific; it prefers the delta-absolute configuration of the metal complexes. The importance of the metal center and its adjacent functionalities for the stereospecific recognition of ferrichromes via TonA is discussed.
Renal Tubular Localization of Chlormerodrin Labeled with Mercury-203 by Autoradiography

An autoradiographic technique has been developed for determining the intrarenal distribution of therapeutic doses of chlormerodrin labeled with mercury-203. Highest concentrations of mercury were detected in the straight portion of the proximal tubule in the rat and in the convoluted portion of the proximal tubule in the dog.
Isoflurane therapy for severe refractory status asthmaticus in children

To describe the use of inhaled isoflurane in a series of children with life-threatening asthma. Retrospective case series. Pediatric intensive care unit of a tertiary-care children's hospital. Ten children ranging in age from 1 to 16 years with 11 episodes of severe asthma requiring invasive mechanical ventilation in the pediatric intensive care unit over a 5-year period. Isoflurane resulted in an improvement in arterial pH and a reduction in partial pressure of arterial carbon dioxide (PaCO2) in all the 11 instances. This effect was sustained in 10 cases and led to clinical improvement and rapid weaning from mechanical ventilation. One child failed to show sustained response and was placed on veno-venous extracorporeal membrane oxygenation. One child died secondary to anoxic brain injury sustained prior to hospitalization. Hypotension was the major side effect, and occurred in 8 children necessitating vasopressor support. Isoflurane improves arterial pH and reduces partial pressure of arterial carbon dioxide in mechanically ventilated children with life-threatening status asthmaticus who are not responsive to conventional management.
Generalized Einstein relations from a three-temperature theory of gaseous ion transport

Abstract Generalized Einstein relations between mobility and diffusion coefficients are derived within the framework of a recently developed three-temperature kinetic theory of gaseous ion transport. A previously assumed connection between diffusion and differential mobility is firmly established within low-order approximations of the kinetic theory. Equations are obtained for the approximate calculation of the unobservable parallel and perpendicular ion temperatures, and for two higher moments of the ion velocity distribution function that appear as correction terms in the generalized Einstein relations. The present theory is tested on inverse-power potentials and on several alkali ion-noble gas systems, and is compared to two previous semi-empirical generalized Einstein relations. Simple procedures are recommended for the estimation of the parameters and correction terms that occur, to permit approximate calculation of gaseous ion diffusion coefficients from mobility data without the need of a computer or specific knowledge of the ion-neutral interaction potential.
Design and Characterization of Micro-Compressor Impellers

A study has been conducted, using steady three-dimensional Reynolds-averaged Navier-Stokes simulations (FLUENT) to investigate dominant performance limiting mechanisms for micro-scale, high-speed compressor impellers with diameter in the range of 5mm to 10mm and peripheral speed ∼ 500 ms−1 . Heat transfer to impeller flow (hence non-adiabatic in contrast to nearly adiabatic macro-scale centrifugal compressors for aircraft engine application), casing drag, and impeller passage boundary layer loss are identified as micro-scale impeller performance limiting mechanisms. Heat transfer could lead to up to 25 efficiency points penalty, casing drag to about 10–15 points, and passage boundary layer loss to another 10 points for the investigated micro-impellers. Micro-impeller efficiency of up to 90% is achievable if design is directed at mitigating these performance limiting mechanisms. The effect of heat addition on impeller performance is detrimental and depends on a single non-dimensional parameter (ratio of added heat to inlet stagnation enthalpy). The performance penalty is associated with the physical fact that compression at high temperatures requires more work. Casing drag associated with impeller rotating relative to stationary casing results in a torque on the flow near the casing and impeller blade tip that can be characterized in terms of rotational Reynolds number and ratio of tip clearance to impeller radius. Channel boundary layer loss can be characterized in terms of Reynolds number, geometry (impeller exit-to-inlet diameter ratio, blade angles, chord-to-inlet diameter ratio, average-to inlet span ratio, inlet diameter-to-inlet span ratio), and exit-to-inlet temperature ratio related to work input (rotor geometry and speed). A physics-based model is developed for quantifying each of these performance-limiting processes, given the key design parameters. The results from the models are in accord with CFD (FLUENT) data. Implications on impeller design are discussed and design guidelines are formulated. The paper reports a quantitative investigation of micro-turbomachinery performance limiting mechanisms and offers design guidelines based on physical understanding.Copyright © 2004 by ASME
Escape strategy and vocalization during escape by American Bullfrogs (Lithobates catesbeianus)

American bullfrogs, Lithobates catesbeianus , escape by jumping into water and submerging, often vocalizing as they flee. I studied effects of several risk factors on escape and refuge use and the association between vocalization by fleeing frogs and escape by other individuals nearby. Frogs on shore permitted equally close approach when approached along the shore or on a path perpendicular to shore. Frogs in water were more likely to flee when closer to shore and when approached more rapidly. Time spent submerged after fleeing was uncorrelated with proximity of the predator upon escape. Frogs spent longer submerged when they swam along shore away from the point of entry than when they surfaced directly offshore. Neither distance offshore nor Euclidean distance from the entry point upon emergence was related to time spent submerged. Bullfrogs may use unpredictability of distance and direction moved underwater and of duration of submergence as a strategy that reduce risk upon surfacing. When a focal frog vocalized as it fled, immediate escape by nearby nonfocal frogs was more frequent than when focal frogs (1) escaped without vocalization and (2) neither escaped nor vocalized. These findings are consistent with either alarm calling or benefit to the fleeing individual due to brief delay of attack by a predator. They are inconsistent with several other possible functions of calling during escape. Experimentation is needed to definitively test the hypothesis that calls during escape are alarm signals.
Cold shock and rapid cold-hardening of pharate adult flesh flies (Sarcophaga crassipalpis): effects on behaviour and neuromuscular function following eclosion

. Little is known about the nature of injury due to cold shock, or its prevention by rapid cold-hardening, in insects. To understand these phenomena better at the system level, physiological and behavioural comparisons were made between control, cold shock injured, and rapidly cold-hardened flesh flies, Sarcophaga crassipalpis Macquart (Diptera, Sarcophagidae). Cold shock impaired the proboscis extension reflex in response to 0.125,0.5 and 1.0 M sucrose solutions. Cold shock-injured flies were unable to groom effectively and spent only 12.5% of the first 5 min following general dust application producing ineffectual leg movements. In contrast, control and rapidly cold-hardened flies exhibited normal grooming behaviour spending 92.4% and 94.1% of the first 5 min following generalized dust application grooming. Cold shock also decreased the mean resting membrane potential of tergotrochanteral muscle fibres from -65.9 mV in control flies to -41.6 m V. Conduction velocities of the three motor neurone populations innervating the tergotrochanteral muscle were all significantly lower in cold-shocked flies than in control or rapidly cold-hardened flies. Finally, cold shock impaired neuromuscular transmission as evidenced by a lack of evoked end plate potentials.
Histochemical localization of cholinesterase in the brain of the cockroach (Periplaneta americana)

Abstract The histochemical localization of cholinesterase in the cockroach (Periplaneta americana) brain was investigated and compared to the localization of catecholamines as described by others. An inverse relationship occurs in many areas. The calyx, negative after catecholamine staining, stains with cholinesterase in its ventral two-thirds. The alpha and beta lobes appear striped after catecholamine staining and are unstained by cholinesterase. Neuronal cell groups stained by catecholamines are unstained by cholinesterase. A few cells of the pars intercerebralis are stained by cholinesterase, but not by catecholamines. Neuropiles in all lobes of the brain are stained intensely by cholinesterase, while only a few fibers in these areas are seen after catecholamine procedures. The medulla of the optic lobe, unstained by catecholamines, is stained intensely by cholinesterase. An external semilunar zone of the lobula of the optic lobe is stained intensely by cholinesterase and after catecholamine procedures. Neither transmitter can be found in the globuli cells, the dorsal one-third of the calyx, the stem of the mushroom body, and between the catecholaminergic stripes of the alpha and beta lobes. Both transmitters can be found in parts of the central body.
Quality assurance review of death certificates: a pilot study.

BACKGROUND:: Although quality assurance programs for medical examiners are required by the National Association of Medical Examiners' Inspection and Accreditation Checklist, quality assurance programs specifically targeting death certificate completion have not been addressed. The Fulton County Medical Examiner, Atlanta, GA, has implemented a pilot quality assurance program for death certificate information, and this report contains information about 1 year's experience with the program. METHODS:: All death certificates are reviewed by the case medical examiner(s) and chief medical examiner prior to their release to funeral homes. Death certificates with errors are retained for quality assurance and review purposes, and needed corrections are made before death certificates are released. During a 1-year period, death certificates with errors were collected and then reviewed and tabulated by type of error. RESULTS:: Between May 26, 2003, and May 25, 2004, the Fulton County Medical Examiner certified 1267 deaths. Of these, 47 (4%) were found to contain errors that were corrected and an additional 52 (4%) had been amended for various reasons. The most common errors were misspellings in causes of death or poor or incomplete wording in injury-related information. Forty-seven percent of errors involved omitted, incomplete, or incorrect information that was potentially significant. The most common reason for amended certificates was unexpected detection of acute intoxications among people with significant cardiovascular disease. CONCLUSIONS:: Quality assurance review of death certificates can assist in preventing the release of death certificates with incomplete, erroneous, or omitted information and may also be useful as an educational forum regarding completion of the death certificate.
Scratching around stress: Hierarchy and reconciliation make the difference in wild brown lemurs (Eulemur fulvus)

The scratching–stress linkage has been demonstrated in monkeys and apes but never in strepsirrhines, either in the wild or in captivity. We analysed data collected on a 14-animal group of Eulemur fulvus in the Berenty forest (South Madagascar, March–July 2008). We applied a protocol (same weather conditions, time slot, social/activity context, forest quadrat, and subgroup formation) involving four conditions, under which we recorded the scratching response: predation attempt, reconciled conflict, non-reconciled conflict, and control. We found that the scratching–stress linkage remains valid in strepsirrhines. Scratching increased after predatory attacks by the hawk Polyboroides radiatus and intra-group aggressions and decreased after reconciliation, probably buffering post-conflict stress. Scratching negatively correlated with the linear hierarchy, but only in the absence of stressful events. Compared to aggressions, predation attempts induced a greater increase in scratching, with dominants showing the h...
Consumer Similarity Judgments: A Test of the Contrast Model

A general model is described that views similarity judgment as a contrasting of product features. The relative influence of common and distinctive features on perceived similarity is considered a function of the context or task environment. A memory probe is used to measure the common and distinctive features consumers associate with various products. The feature measures are then used to estimate the model under three different task environments: similarity, dissimilarity, and subject/referent similarity. The results support the model and the effect of the task environment on judgments of interproduct similarity.
Advances in Skull Base Imaging

Despite being introduced in the 1970s and 1980s, CT and MRI continue to be the primary imaging modalities for the temporal bone and skull base. Although the general concepts and physics remain the same, the images obtained currently are far superior. Augmenting these traditional modalities are nuclear medicine imaging techniques, functional imaging, and the fusion of different techniques. Advances in these areas are expanding our options and illuminating pathology in unique ways. As basic physiologic processes are better understood, new opportunities for novel imaging techniques should arise.
Frequency dependence of amorphous silicon Schottky diodes for Large-Area rectification applications

Schottky diodes can play a valuable role as rectifiers in Large-Area Electronics (LAE) systems and circuits. They can be used to recover a DC signal when an AC carrier is used to transmit signals between adjacent plastic electronic sheets through near-field wireless coupling [1], rectify DC power after AC transmission between sheets to provide power to sensors, and so forth. In this paper we describe: 1) the intrinsic frequency limits of Schottky diodes fabricated on hydrogenated amorphous silicon (a-Si:H); 2) circuit design strategies for using the diodes at frequencies far beyond their intrinsic limits; 3) and the application of these strategies to demonstrate, to the best of out knowledge, the first amorphous silicon (a-Si:H) full-wave rectifier, with an AC-to-DC power conversion efficiency (PCE) ranging from approximately 46% at 200 Hz to greater than 10 % at 1 MHz.
Dim target tracking with total variation and genetic algorithm

This paper presents an effective and fast algorithm to detect and track low observable targets in a digital image sequence. At first, we use Total Variation (TV) filtering technique to improve the Signal to Noise Ratio (SNR) and remove the noise in the input image. Following this step, an encoding scheme along with genetic operation is designed to track the targets. To avoid missing any tracks, the individual preservation method is introduced to maintain more promising candidate tracks. Target trajectories are then confirmed by a multi-stage hypothesis testing scheme. The simulation results show that the proposed scheme can efficiently detect and track small targets with an SNR value under 2db.
Microsurgical subinguinal varicocelectomy with testicular delivery

Objective To demonstrate our approach to the microsurgical subinguinal varicocelectomy with testicular delivery. Design An instructional video demonstrating the surgical procedure in a step-by-step manner, highlighting useful surgical techniques. Setting Not applicable. Patient(s) Patients with male factor infertility. Intervention(s) After appropriate patient selection and counseling, varicocelectomy is performed with a subinguinal approach utilizing the surgical microscope. The patient is under general anesthesia and we employ an operating microscope. The patient is positioned supine. Main Outcome Measure(s) Not applicable. Results A 2.5-cm subinguinal incision was made and the testicle was then delivered. Through the operating microscope at 10-20X magnification, internal spermatic veins were identified and ligated. Smaller veins were taken with electrocautery. The testicular artery was identified using the microdoppler probe. We employ hydrodissection in identifying and isolating the testicular artery. The spermatic cord is then repeatedly examined until no veins other than deferential veins remain. The gubernaculum is also thinned sufficiently so that veins on both sides can be identified and ligated. Testicular delivery was performed and external spermatic veins as well as gubernacular veins ligated. Conclusion(s) Varicoceles are found in up to 15% of all men, and in up to 40% of infertile men. Varicoceles have negative effects on testicular function. Varicocelectomy improves testicular function and may halt the accelerated rate of decline in testicular function associated with varicoceles. Sperm parameters, serum testosterone levels, and pregnancy rates have all been shown to improve following varicocelectomy. Use of the operating microscope, the microdoppler probe, and black and white sutures aid in efficiency. Testicular delivery is useful to ligate external spermatic veins as well as gubernacular veins. This study received institutional review board approval from the Emory University IRB (#00066701).
A Theorem of Frobenius, a Theorem of Amitsur-Levitski and Cohomology Theory

Let U be a complex n-dimensional vector space and G = G(U) the group of all non-singular linear transformations on U. If r U = ? r U is the space of r-tensors over U, then it is a well known theorem that the group G and the symmetric group S = S r both admit natural representations on r U and that the algebras generated by the two image groups are each other’s commutators.
An oscillating-boundary-layer theory for ciliary propulsion

This paper analyses the locomotion of a finite body propelling itself through a viscous fluid by means of travelling harmonic motions of its surface. The methods are developed with application to the propulsion of ciliated micro-organisms in mind. Provided that the metachronal wavelength (of the surface motions) is much smaller than the overall dimensions of the body, the flow can be divided into an oscillating-boundary-layer flow to which is matched an external complementary Stokes flow. The present paper employs the envelope model of fluid/cilia interaction to construct equations of motion for the oscillating boundary layer. The final solution for the propulsive velocity is obtained by application of the condition of zero total force on the self-propelling body; alternatively, if the organism is held at rest, the thrust it generates can be computed. Various optimum propulsive velocities for self-propelling bodies and optimum thrusts for restrained bodies are analysed in some simple examples. The results are compared with the relatively sparse observations for a number of micro-organisms.
Stratabound geothermal resources in North Dakota and South Dakota

Analysis of all geothermal aquifers in North Dakota and South Dakota indicates an accessible resource base of approximately 21.25 exajoules (10{sup 18} J = 1 exajoule, 10{sup 18} J{approximately}10{sup 15} Btu=1 quad) in North Dakota and approximately 12.25 exajoules in South Dakota. Resource temperatures range from 40{degree}C at depths of about 700 m to 150{degree}C at 4500 m. This resource assessment increases the identified accessible resource base by 31% over the previous assessments. These results imply that the total stratabound geothermal resource in conduction-dominated systems in the United States is two-to-three times greater than some current estimates. The large increase in the identified accessible resource base is primarily due to inclusion of all potential geothermal aquifers in the resource assessment and secondarily due to the expanded data base compiled in this study. These factors were interdependent in that the extensive data base provided the means for inclusion of all potential geothermal aquifers in the analysis. Previous assessments included only well-known aquifer systems and were limited by the amount of available data. 40 refs., 16 figs., 8 tabs.
Degradation and failure mechanisms of a-Si:H solar cells with aluminum contacts

Low temperature (100/spl deg/C-300/spl deg/C) annealing effects on a-Si:H solar cells with Al contacts have been investigated. A reduction in shunt resistance upon annealing in the temperature range of 150-180/spl deg/C for thirty minutes was observed indicating degradation of the cells. Visible morphological changes of the aluminum surface and the a-Si:H film underneath initiate at approximately 170/spl deg/C. Thirty minute annealing at 180/spl deg/C decreased the shunt resistance by a factor of 50 and the solar cells showed a considerable decrease in efficiency and fill factor. Annealing at 200/spl deg/C and higher degraded the solar cells to the point that no conversion occurred. The degradation and failure mechanisms of the solar cells can be explained using a simple model involving aluminum diffusion into the silicon followed by crystallization and type conversion of the n/sup +/ a-Si:H due to aluminum counterdoping.
Tumor suppressor pRB functions as a co-repressor of the CCAAT displacement protein (CDP/cut) to regulate cell cycle controlled histone H4 transcription.

The CCAAT displacement protein (CDP-cut/CUTL1/cux) performs a key proliferation-related function as the DNA binding subunit of the cell cycle controlled HiNF-D complex. HiNF-D interacts with all five classes (H1, H2A, H2B, H3, and H4) of the cell-cycle dependent histone genes, which are transcriptionally and coordinately activated at the G(1)/S phase transition independent of E2F. The tumor suppressor pRB/p105 is an intrinsic component of the HiNF-D complex. However, the molecular interactions that enable CDP and pRB to form a complex and thus convey cell growth regulatory information onto histone gene promoters must be further defined. Using transient transfections, we show that CDP represses the H4 gene promoter and that pRB functions with CDP as a co-repressor. Direct physical interaction between CDP and pRB was observed in glutathione-S-transferase (GST) pull-down assays. Furthermore, interactions between these proteins were established by yeast and mammalian two-hybrid experiments and co-immunoprecipitation assays. Confocal microscopy shows that subsets of each protein are co-localized in situ. Using a series of pRB mutants, we find that the CDP/pRB interaction, similar to the E2F/pRB interaction, utilizes the A/B large pocket (LP) of pRB. Thus, several converging lines of evidence indicate that complexes between CDP and pRB repress cell cycle regulated histone gene promoters.
Algorithm to test the structural plausibility of a proposed elementary reaction

An algorithm is introduced that tests whether a proposed elementary reaction can be realized within a specified number of cleavages and formations of covalent bonds. This is related to the problem of computing the minimum chemical distance of a given stoichiometry, but differs from it in important ways that are exploited in the algorithm design. One application of the algorithm is as a filter in MECHEM—a computer aid for the elucidation of reaction pathways. In that application, reaction steps implying more changes to covalent bonds than a given threshold are ruled implausible, and in practice such tests need to be carried out many thousands of times. Future applications of the algorithm can be expected because the question addressed is a fundamental one: What elementary reactions can occur? © 1993 by John Wiley & Sons, Inc.