cssi/SciSciGPT-SciSciNet huggingface dataset:
Effect of head position on upper airway function in exercising horses

Summary The objective of the present study was to determine the effect of head and neck position on upper airway flow mechanics in exercising horses. Five Standardbred horses (452 ± 16.5 kg bwt; 4.7 ± 0.9 years [mean ± s.e.]) were exercised at 75% (Period A) and at 100% of maximal heart rate (Period B) with head and neck unrestrained, extended, or flexed. Airflow was measured using a facemask mounted pneumotachograph, while tracheal pressure during inhalation and exhalation (PUI and PUE) was measured using a nasotracheal catheter. With head and neck unrestrained, PUI, PUE, inspiratory and expiratory impedance (ZI, ZE), respiratory frequency (f) and indices describing the tidal breathing flow-volume loops (TBFVLs) were similar to those previously reported. There were no significant changes in the extended position, except that expiratory time (Te) and ratio of peak expiratory flow and peak inspiratory flow (PEF/PIF) were significantly increased in Periods A and B, respectively. In contrast, in the flexed position, ZI was significantly increased in Period B. Also, inspiratory flow at 50% of tidal volume (IF50) was significantly decreased, and PEF/PIF and EF50/IF50 were significantly increased. At period A, PUI was increased and Te was prolonged. We conclude that during strenuous exercise head and neck extension has little effect on upper airway flow mechanics, but that head and neck flexion causes upper airway obstruction.
Dispersal of Boll Weevils (Coleoptera: Curculionidae) from Cotton Modules Before Ginning

Abstract We characterized the level of risk of boll weevil, Anthonomus grandis grandis Boheman, reintroduction to an eradication zone posed by dispersal from cotton modules during and after transport to the gin. Mark–release-recapture experiments in August and September in Texas indicated that most weevils disperse rapidly from the module surface, temperature permitting, unless confined under a module tarp, where most died. Nevertheless, 1–5% of released weevils were recovered alive after 24 h on the side and top surfaces of modules, representing potential dispersants. Mortality of boll weevils caged on the top surface of a module was 95–100% after 1–4 d when maximum air temperatures were ≥33°C and 72–100% when minimum temperatures were −7°C or lower, but a few survived even after experiencing a minimum daily temperature of −12°C. Under warm (daily maximum temperatures ≥25°C) and cold (daily minimum temperatures ≤0°C) weather conditions, survival was higher under the tarp than on the open surface of the m...
Racing performance after combined prosthetic laryngoplasty and ipsilateral ventriculocordectomy or partial arytenoidectomy: 135 Thoroughbred racehorses competing at less than 2400 m (1997-2007).

Summary Reasons for performing study: The success of combined prosthetic laryngoplasty with ipsilateral ventriculocordectomy (LPVC) has not been compared to that of partial arytenoidectomy (PA) in a clinical population. Hypotheses: In Thoroughbred (TB) racehorses: 1) earnings after LPVC are unaffected by the severity of recurrent laryngeal neuropathy (RLN) (laryngeal grade III vs. grade IV); 2) LPVC and PA yield similar results in the treatment of grade III RLN; 3) performance outcome following PA is independent of diagnosis (RLN vs. unilateral arytenoid chondritis [UAC]); and 4) neither LPVC nor PA returns horses to the level of performance of controls. Methods: Medical and racing records of 135 TB racehorses undergoing LPVC or PA for the treatment of grade III or IV RLN or UAC were reviewed. Racing records of age and sex matched controls were also reviewed. Results: After LPVC, horses with grade III RLN performed better compared to those with grade IV RLN. Furthermore, horses treated for grade III RLN by LPVC showed post operative earnings comparable to controls. Rate of return to racing were similar for PA and LPVC, although LPVC resulted in higher post operative earnings. Performance after PA was similar regardless of diagnosis (UAC or RLN). Finally, neither LPVC when performed for grade IV RLN, nor PA performed for either diagnosis restored post operative earnings to control levels. Conclusions: Thoroughbred racehorses treated by LPVC for grade III RLN show significantly better post operative earnings compared to horses treated for grade IV disease. In grade III RLN, LPVC returns earning potential to control levels. PA and LPVC lead to similar success in terms of rate of return to racing, but PA leads to inferior earnings after surgery. Potential relevance: Laryngoplasty should be recommended for all TB racehorses with grade III RLN to maximise return to racing at a high level. This contradicts the common approach of waiting for complete paralysis.
Leg coordination mechanisms in the stick insect applied to hexapod robot locomotion

Three of the mechanisms believed to be responsible for leg coordination in the stick insect, Carausius morosus, are used to control the straight-line locomotion of a hexapod robot on a smooth surface. The robot walks with a continuum of statically stable insectlike gaits in response to a single, scalar user input that controls the speed of locomotion. This control strategy is highly robust in the sense that the controller continues to maintain its basic function of causing the robot to walk effectively despite large perturbations to the controller. This controller robustness was demonstrated by inducing a wide variety of lesions (severing of connections) and performing parameter sensitivity studies.
Synthesis, Characterization, Luminescence, and Electrochemistry of New Tetranuclear Gold(I) Amidinate Clusters: Au4[PhNC(Ph)NPh]4, Au4[PhNC(CH3)NPh]4, and Au4[ArNC(H)NAr]4

The syntheses and the X-ray structures of the tetranuclear gold(I) benzamidinate, Au4[PhNC(Ph)NPh]4, and the tetranuclear gold(I) acetamidinate, Au4[PhNC(CH3)NPh]4, clusters are reported. The clusters are produced by the reaction of the sodium salt of an amidine ligand with the gold precursor Au(THT)Cl in a (1:1) stoichiometry. The average Au...Au distance between adjacent Au(I) atoms is ∼2.9 A, typical of compounds having an aurophilic interaction. The four gold atoms are arranged in a square (Au...Au...Au... = 88–91°) in the acetamidinate and in a distorted square (Au...Au...Au... = 82–97°) in the benzamidinate derivative. Electrochemical oxidation of the tetranuclear complex Au4[PhNC(Ph)NPh]4 show three reversible waves at 0.87, 1.19, 1.42 V vs. Ag/AgCl at a scan rate of 100 mV/s in CH2Cl2 similar to the three reversible waves seen before from the tetranuclear complexes Au4[ArNC(H)NAr]4, Ar = C6H4-4-OMe, Ar = C6H4-4-Me, and Ar = C6H3-3,5-Cl. A summary of the chemistry of the tetranuclear Au(I) amidinate complexes Au4[ArNC(H)NAr]4, Ar = C6H4-4-OMe, C6H3-3,5-Cl, C6H4-4-Me, C6H4-3-CF3, C6F5, C10H7 also is presented. The tetranuclear clusters Au4[ArNC(H)NAr]4, Ar = C6H4-4-OMe, Ar = C6H4-3-CF3, Ar = C6H4-4-Me and Ar = C6H4-3,5-Cl are the first tetranuclear gold(I) cluster species from group 11 elements to show fluorescence at room temperature. The lifetimes of the naphthyl and trifluoromethylphenyl complexes are in the millisecond range indicating phosphorescent processes. Recently it has been shown that Au4[ArNC(H)NAr]4 are very effective catalysts upon calcination for room temperature CO oxidation.
The effects of hydrogen on viscoelastic relaxation in Zr–Ti–Ni–Cu–Be bulk metallic glasses: implications for hydrogen embrittlement

Abstract The effects of hydrogen on the viscoelastic relaxation behavior of a Zr–Ti–Ni–Cu–Be bulk metallic glass have been investigated in an attempt to elucidate hydrogen-affected flow and fracture behavior. Dynamic mechanical testing was performed to study relaxation behavior near the glass transition temperature. Relaxation time constants were increased in the presence of hydrogen with a concomitant increase of thermal activation energy. In addition, the glass transition temperature was increased and crystallization kinetics retarded in the presence of hydrogen leading to enhanced thermal stability. Positron annihilation spectroscopy was employed to study the interaction of hydrogen and open-volume regions. While hydrogen charging was found to decrease the open-volume regions in the amorphous phase, an increase in free volume was observed in the crystalline counterpart. The amorphous phase was found to have a greater hydrogen absorption capacity compared to its crystalline counterpart. Relaxation behavior, crystallization kinetics and the interaction of hydrogen with the amorphous microstructure are discussed. Finally, the effects of retarded relaxation processes on fracture resistance are considered.
Electroporation of human skin: simultaneous measurement of changes in the transport of two fluorescent molecules and in the passive electrical properties

Abstract The stratum corneum (SC) of mammalian skin is a formidable barrier to the transport of both small ions and charged molecules, but large, very rapid increases in transport can be created by “high-voltage” pulses. Here a series of exponential pulses (√pulse = 1.1 ms) was used in vitro with human skin preparations. A flow-through apparatus provided simultaneous, continuous measurements for the transport of two fluorescent molecules (calcein, 623 Da, charge of zcal = −4; sulforhodamine, 607 Da, charge of zsr = −1) and the skin's passive electrical properties, with emphasis on the transdermal conductive behavior, which includes both the d.c. conductance, Gskin, and the non-linear dynamic conductance, Gdy. “High-voltage” pulsing was found to cause large and very rapid changes in the molecular flux of both molecules, and also in Gskin and Gdy. In the case of molecular transport, the relative contribution of local diffusion and local electric field-driven transport depends significantly on the molecular charge, zs. The field-driven transport during a pulse allowed estimates of the maximum fractional aquerous area Fw,s, of the skin that was transiently available during a pulse for small ions (Fw, ions = 6 ± 3 × 10−4), calcein (Fw, cal = 5 ± 3 × 10−5), and sulforhodamine (Fw,sr = 7 ± 4 × 10−5). Comparison of the post-pulse recovery of Gskin and the decrease of the molecular transport showed that the recovery of the skin barrier and molecular flux decay are not identical. These results are interpreted as being due to electrical creation of new aqueous pathways (“pores”) across the lipid regions of the skin's stratun corneum, and support the hypothesis that elecroporation is responsible for the rapid and large changes observed.
Parallel Navigation Algorithms For An Autonomous Mobile Robot

Recently an approach to the problem of robot navigation in an unexplored terrain was develped by Iyengar, et al, which involves concepts of learning. The method proposed involves representing the terrain as a spatial graph which is updated as the robot undertakes a number of goal-directed traversals. The current paper focuses on the implementation of the spatial graph data structure and Parallel Algorithms needed to maintain the data structure. A modified adjacency list data structure is proposed for representing the spatial graph of the terrain. The model of computation being used is the multiple instruction stream multiple data stream shared memory model MIMD-SMM. The parallel algorithms required to implement the navigation technique (described in the previously mentioned paper) using the modified adjacency list data structure are presented and the time and space complexities of the various algorithms are discussed. The algorithms presented provide the basis for an efficient navigation sytem for an autonomous robot working in an unexplored terrain.
Fertilizers to support agricultural development in sub-Saharan Africa: what is needed and why☆

Abstract Substantial growth in inorganic fertilizer use is a prerequisite for sustained agricultural growth in sub-Saharan Africa. Increased fertilizer use can lead to modest but immediate and important increases in yields, while the profitability of other technologies will be stifled without adequate plant nutrients. Average fertilizer application rates in sub-Saharan Africa need to increase from 10 kg/ha to 50 kg/ha within 10 years to prevent mining of soil nutrients. That implies an 18% annual growth rate. This is substantially higher than trends in the region, but within a reasonable range of historically observed levels from other parts of the world. While over-use of fertilizers can create environmental problems, this is not a widespread problem in sub-Saharan Africa, and should not become one as a result of applying 50 kg/ha of inorganic fertilizers. Rather, near-term environmental concerns in agriculture in sub-Saharan Africa will stem from the lack of intensification. Farmer demand for fertilizers and the physical capacity to make fertilizers available are the two key issues that determine whether a 50-kg/ha goal will be attained. However, demand-side incentives cannot be separated from fertilizer supply possibilities. Several studies document that the simple physical availability of fertilizers to farmers, in the appropriate quantity, packages and at the appropriate time of year, remains a main constraint on increased fertilizer use in sub-Saharan Africa.
Risk Dimensions and Political Decisions Frame Environmental Communication: A Content Analysis of Seven U.S. Newspapers From 1970–2010

This project examined the focus of environmental news frames used in seven American newspapers between 1970 and 2010. During this time newspapers were a primary source of news. Based on gatekeeping and agenda-setting theory, as well as source credibility, the content analysis of 2,123 articles examined the environmental topics within the articles, seven possible risk perception dimensions used in the story, and the primary source of information. The national newspapers typically reported an environmental issue paired with policy; local papers reported a single environmental issue. A Chi-square test found significant differences between national and local newspapers’ use of risk dimensions.
Modifications to the microstructural topology in f.c.c. materials through thermomechanical processing

Abstract Recently, there has been increased attention toward determination of the grain boundary character distribution (GBCD) and manipulation of the relative fractions of “special” and “random” boundaries in the microstructure through thermomechanical processing techniques in order to improve materials properties like corrosion, creep resistance, and weldability. Most of the “optimization” treatments reported in the literature have been performed on f.c.c. metals and alloys with medium to low stacking fault energies, and have resulted in microstructures with high fractions of Σ3, Σ9, and Σ27 boundaries, or Σ3n boundaries. Experiments to modify the GBCD of oxygen-free electronic Cu and Inconel 600 through sequential thermomechanical processing are presented and the efficacy of these processing routes is assessed in terms of microstructural descriptors like the random grain boundary network and the distribution of triple junctions. This analysis has shown that Σ3n reactions, which occur as a consequence of multiple twinning, not only improve the GBCD but are also critical for disrupting the connectivity of the random boundary network.
Ribonucleotide reductase subunit R1: a gene conferring sensitivity to valproic acid-induced neural tube defects in mice.

Neural tube defects (NTDs), although prevalent and easily diagnosed, are etiologically heterogeneous, rendering mechanistic interpretation problematic. To date, there is evidence that mammalian neural tube closure (NTC) initiates and fuses intermittently at four discrete locations. Disruption of this process at any of these four sites may lead to a region-specific NTDs, possibly arising through closure site-specific genetic mechanisms. Although recent efforts have focused on elucidating the genetic components of NTDs, a void persists regarding gene identification in closure site-specific neural tissue. To this end, experiments were conducted to identify neural tube closure site-specific genes that might confer regional sensitivity to teratogen-induced NTDs. Using an inbred mouse strain (SWV/Fnn) with a high susceptibility to VPA- induced NTDs that specifically targets and disrupts NTC between the prosencephalon and mesencephalon region (future fore/midbrain; neural tube closure site II), we identified a VPA-sensitive closure site II-specific clone. Sequencing of this clone from an SWV neural tube cDNA library confirmed that it encodes the r1 subunit of the cell cycle enzyme ribonucleotide reductase (RNR). The abundance of rnr-r1 mRNA was significantly increased in response to VPA drug treatment. This upregulated expression was accompanied by a significant decrease in cellular proliferation in the closure site II neural tube region of the embryos, as determined by ELISA cellular proliferation assays performed on BrdU-pulsed neuroepithelial cells in vivo. We hypothesize that rnr-r1 plays a critical role in the development of VPA-induced exencephaly. Teratology 61:305–313, 2000. © 2000 Wiley-Liss, Inc.
Descending input from the vestibulolateral cerebellum suppresses electrosensory responses in the dorsal octavolateralis nucleus of the elasmobranch, Raja erinacea

1. The dorsal octavolateralis nucleus is the primary electrosensory nucleus in elasmobranchs and receives a major descending input from the dorsal granular ridge (DGR), a part of the vestibulolateral cerebellum. Removal of DGR altered the response properties of ascending efferent neurons (AENs), the projection neurons of the dorsal octavolateralis nucleus. 2. Elimination of DGR by lesion or lidocaine microinjection increased the excitability in AENs. Spontaneous activity increased by 680% and receptive fields became 1300% larger. The sensitivity of AENs to electric field stimuli increased by 560% and the time constant of adaptation increased by 300%, while threshold sensitivity remained unchanged. 3. Some electrosensory units responded to proprioceptive stimuli. In intact animals, the spontaneous activity of AENs was much less modulated by changes in fin position than primary electroreceptor afferents. Lesions to DGR appeared to increase the responsiveness of AENs to changes in fin position. 4. These results indicate that the action of DGR on the dorsal octavolateralis nucleus is primarily inhibitory and may function in a gain control mechanism. The possibility also exists for a mechanical-reafferent reduction mechanism in the electrosensory system of the elasmobranch that may be mediated by DGR.
Uncoupling of increased cellular oxidative stress and myocardial ischemia reperfusion injury by directed sarcolemma stabilization

Myocardial ischemia/reperfusion (I/R) injury is a major clinical problem leading to cardiac dysfunction and myocyte death. It is widely held that I/R causes damage to membrane phospholipids, and is a significant mechanism of cardiac I/R injury. Molecular dissection of sarcolemmal damage in I/R, however, has been difficult to address experimentally. We studied here cardiac I/R injury under conditions targeting gain- or loss-of sarcolemma integrity. To implement gain-in-sarcolemma integrity during I/R, synthetic copolymer-based sarcolemmal stabilizers (CSS), including Poloxamer 188 (P188), were used as a tool to directly stabilize the sarcolemma. Consistent with the hypothesis of sarcolemmal stabilization, cellular markers of necrosis and apoptosis evident in untreated myocytes were fully blocked in sarcolemma stabilized myocytes. Unexpectedly, sarcolemmal stabilization of adult cardiac myocytes did not affect the status of myocyte-generated oxidants or lipid peroxidation in two independent assays. We also investigated the loss of sarcolemmal integrity using two independent genetic mouse models, dystrophin-deficient mdx or dysferlin knockout (Dysf KO) mice. Both models of sarcolemmal loss-of-function were severely affected by I/R injury ex vivo, and this was lessened by CSS. In vivo studies also showed that infarct size was significantly reduced in CSS-treated hearts. Mechanistically, these findings support a model whereby I/R-mediated increased myocyte oxidative stress is uncoupled from myocyte injury. Because the sarcolemma stabilizers used here do not transit across the myocyte membrane this is evidence that intracellular targets of oxidants are not sufficiently altered to affect cell death when sarcolemma integrity is preserved by synthetic stabilizers. These findings, in turn, suggest that sarcolemma destabilization, and consequent Ca(2+) mishandling, as a focal initiating mechanism underlying myocardial I/R injury.
Interdisciplinarity in Doctoral Social Work Education: Does It Make a Difference?.

Interdisciplinarity in doctoral education currently is strongly advocated by governments and universities as important in developing knowledge useful in addressing significant public problems. However, the efficacy of these claims has not been subject to empirical investigation. Using longitudinal data covering a 13-year period, this research addresses this limitation by examining how variation in interdisciplinary emphasis in social work doctoral programs affects the scholarly orientation and productivity of graduates. The findings suggest that interdisciplinary doctoral education makes a difference, with graduates from programs with higher levels of interdisciplinarity demonstrating more generalist scholarly orientations, and achieving higher levels of scholarly productivity.
Electron fringes and standing wave states in a quantum wedge

Abstract A quantum wedge, a nanoscale wedge structure of a metal with its thickness varied monotonically by discrete atomic planes is, in effect, an assembly of quantum wells of incremental sizes and an ideal system for exploring wave properties of electrons under spatial confinement. A set of size-dependent electron standing wave states and their energy spectra formed inside a quantum wedge can be revealed with an atomic accuracy using the STM and STS. The tunnel junction provides an intrinsic mechanism for the energy filtering and contrast enhancement, which facilitates direct STM imaging of electron interference fringes formed spontaneously at the surface of the quantum wedge. Together STM and STS offer a new technique to nondestructively characterize a buried interface in all three dimensions. An atomic lattice buried under a metal film whose thickness is as much as ten times its Fermi wavelength can be clearly resolved with the STM. The fine lateral imaging resolution of a buried lattice is attributable to the anisotropic motion of the confined electrons in the metal and to the dispersion of their discrete transverse energy spectra as a result of the scattering from a boundary with natural atomic corrugations.
Erosion rate variations during XPS sputter depth profiling of nanoporous films

Sputter depth profiling is commonly used to obtain valuable information regarding the three dimensional distribution of elements within a sample, and is one of the best ways to measure the composition of a buried interface or the uniformity of a thin film. X-ray photoelectron spectroscopy (XPS) is one of the analysis tools often used in conjunction with ion beam erosion to obtain sputter depth profiles. However, to obtain accurate depth information it is often necessary to understand better the sputtering process for a specific materials system. Artifacts such as differential sputtering, varying sputter rates and ion beam-induced chemistry are well known. Here, however, we present evidence from experiments on a porous thin film deposited on an Si wafer that relatively small chemical and/or structural changes in a nanoporous film can affect the rate of erosion measured during sputter depth profiling. Reproducible variations in sputter rate are found with chemical modification leading to compositional changes of the nanoporous thin film. The origin of the sputter rate changes is discussed with the aid of results obtained using Fourier transform infrared spectroscopy, profilometry, nuclear reaction analysis, electron microscopy and XPS-based depth profiling.
Davidson's social externalism

Dans l'eventail des conceptions publiques du langage comprenant l'externalisme communal de J. G. Hamann et l'externalisme individualiste de Kant, l'A. etudie la position intermediaire de l'externalisme social de D. Davidson, herite du populisme de J. G. Herder. Rejetant le presuppose d'une seconde personne chez Davidson, et defendant l'idealisme de Herder fonde sur l'exigence de la communaute, l'A. examine l'argument transcendantal pour la necessite de la communaute et l'argument sceptique contre l'externalisme individualiste developpes par Davidson a partir d'une critique de la solution communale au probleme de l'erreur proposee par Quine dans le cadre de sa theorie de la pratique linguistique. Au-dela des interpretation de Herder par H. Arsleff et I. Berlin, l'A. conclut au rejet du pluralisme chez Davidson et a l'obligation d'adopter la position kantienne individualiste
Nitric oxide oxidation method for field calibration of nitrogen dioxide meters

A simple procedure for field calibration of direct-reading NO2 meters is described. The method involves passing NO at a fixed concentration through an oxidizing reagent. The NO is oxidized to NO2, diluted with zero air and routed into the meter. Problems of working with potentially unstable cylinders of NO2 or field permeation systems are avoided. Both laboratory and field evaluations attest to the suitability of this method. Possible application as a confirmatory laboratory standard is suggested.
Do exchange rates follow a random walk process in Middle Eastern countries

Abstract In this note we employ the KPSS test in addition to the ADF test to determine whether the real effective exchange rates in Middle Eastern countries follow a random walk process or they are stationary. While in most cases the KPSS test supported the stationary of the real effective rates, thus the PPP, the ADF test did not. The failure to support the PPP by the ADF test is said to be due to its low power.
Writing and copying in volume holographic memories: approaches and analysis

We analyze and compare three approaches for volume holographic writing/copying in photorefractive media. These include the parallel, incremental, and sequential approaches. We show that the three approaches' achievable grating modulations and total writing/copying times are identical. We then go on to discuss schemes within each approach by which the copying of one volume holographic memory into a secondary volume holographic memory can be optimized. These include all optical, quasiall optical, and opto-electronic schemes. In this analysis, realistic material and device limitations are considered. Our calculations indicate that all optical copying in the parallel approach is the worst option, but opto-electronic copying in the sequential approach is the best option.
Proportional hazards regression with missing covariates

Abstract Nonparametric maximum likelihood (NPML) is used to estimate regression parameters in a proportional hazards regression model with missing covariates. The NPML estimator is shown to be consistent and asymptotically normally distributed under some conditions. EM type algorithms are applied to solve the maximization problem. Variance estimates of the regression parameters are obtained by a profile likelihood approach that uses EM-aided numerical differentiation. Simulation results indicate that the NPML estimates of the regression parameters are more efficient than the approximate partial likelihood estimates and estimates from complete-case analysis when missing covariates are missing completely at random, and that the proposed method corrects for bias when the missing covariates are missing at random.
Pliocene - Pleistocene paleotemperature and paleosalinity history of the Mediterranean Sea: Results from DSDP Sites 125 and 132

Abstract Variations in frequencies of planktonic foraminifera in DSDP Sites 125 and 132 have been used to reconstruct paleotemperature and paleosalinity histories of the eastern and western basins of the Mediterranean Sea for the Pliocene and Quaternary. The reconstructions are derived from transfer functions based on the relationship between the seabed distribution of planktonic foraminifera and overlying hydrographic conditions. This represents the first application of this method to pre-Quaternary sediments and it has been assumed that members of an evolving lineage have similar ecological preferences. Warm sea surface temperatures extend from the middle of the Early Pliocene into the beginning of the Late Pliocene. At this point, the paleotemperature records for both sites indicate a major cooling that appears to be associated with the initiation of Northern Hemisphere glaciation at approximately 3.2 m.y. ago. This is followed by a warming centered over the Pliocene-Pleistocene boundary. Within the Late Pleistocene (approx. 1 m.y. B.P. to present) the magnitude of temperature oscillations increases significantly (from 2–3° C in the Early Pleistocene to 5–6° C in the Late Pleistocene) suggesting intensified glacial/interglacial fluctuations. During the Late Pliocene and Early Pleistocene, both basins are marked by similar summer and winter temperatures indicating a lack of strong east-west trending temperature gradients within the Mediterranean. This changed drastically during the Late Pleistocene when surface temperatures in the eastern basin (Site 125) became significantly warmer than the western basin (Site 132). The paleosalinity histories of the two sites also indicate that up to the Early Pleistocene both basins had similar surface salinities. However, during the Late Pleistocene the eastern basin became more saline than the western basin. Base on these reconstructions, it appears that the strong east-west trending hydrographic gradients that characterize the modern Mediterranean were first establised in the Late Pleistocene at approximately 1 m.y. ago.
The Chat Reference Interview: Practicalities and Advice

SUMMARY The popularity of chat reference services is evident, as seen from participation by libraries of all types and sizes. Librarians have long been taught and honed skills to assist the patron in face-to-face reference interviews, but this new medium has forced librarians to rethink those skills. The article discusses the practicalities of conducting a reference interview through chat, as opposed to face-to-face or in-person reference. Actual chat transcripts and surveys from the chat reference librarians at the University of Minnesota-Twin Cities Libraries are used to illustrate the relationship and tension between instruction and reference in the chat interview. Also included are training suggestions, ways to compensate for the lack of visual cues, and advice from veteran chat reference librarians.
A heuristic scheduler for port-constrained floating-point pipelines

We describe a heuristic scheduling approach for optimizing floating-point pipelines subject to input port constraints. The objective of our technique is to maximize functional unit reuse while minimizing the following performance metrics in the generated circuit: (1) maximum multiplexer fanin, (2) datapath fanout, (3) number of multiplexers, and (4) number of registers. For a set of systems biology markup language (SBML) benchmark expressions, we compare the resource usages given by our method to those given by a branch-and-bound enumeration of all valid schedules. Compared with the enumeration results, our heuristic requires on average 33.4% less multiplexer bits and 32.9% less register bits than the worse case, while only requiring 14% more multiplexer bits and 4.5% more register bits than the optimal case. We also compare our results against those given by the state-of-art high-level synthesis tool Xilinx AutoESL. For the most complex of our benchmark expressions, our synthesis technique requires 20% less FPGA slices than AutoESL.
Heterozygous hemochromatosis as a risk factor for premature myocardial infarction

Abstract Previous studies suggest that risk of premature myocardial infarction is increased by a heritable factor not associated with the conventional risk factors. Among the 5–7% of persons in the general population at high risk, the men are at greater risk than the women. It is proposed that heterozygosity for hemochromatosis increases the susceptibility of the carrier to premature myocardial infarction. This hypothesis explains much of the behavior of the unknown heritable factor, including its independence from the conventional risk factors and its apparent selectivity for men under age 50. Heterozygous hemochromatosis occurs frequently enough to account for the observed number of high risk families. Studies for verification of the hypothesis are proposed.
PGE2 is a more potent vasodilator of the lamb ductus arteriosus than is either PGI2 or 6 keto PGFα

It has been shown in vitro that the lamb ductus arteriosus forms prostaglandins PGE2, PGF2α, 6 keto PGF1α (and its unstable precursor PGI2). In this study the relative potencies of these endogenous prostaglandins were investigated on isolated lamb ductus arteriosus preparations contracted by exposure to elevated PO2 and indomethacin. All the prostaglandins (except PGF2α) relaxed the vessel. This is consistent with the hypothesis that endogenous prostaglandins inhibit the tendency of the vessel to contract in response to oxygen. Only PGE2, however, relaxed the vessel at concentrations below 10−8M. PGI2 and 6 keto PGF1α had approximately 0.001 and 0.0001 times the activity of PGE2. Although PGE2 has been observed to be a minor product of prostaglandin production in the lamb ductus arteriosus, the tissue's marked sensitivity to PGE2 might make it the most significant prostaglandin in regulating the patency of the vessel.
New Autocorrelation and Prediction Techniques for the Demodulation of Binary Signals

The classic problem of detecting a narrowband signal received in a wideband noise is treated via new techniques, namely, autocorrelation computation and linear adaptive filtering. It is shown by analysis and simulation that the proposed techniques yield probility of bit errors cimparable to those provided by coding techniques. Expressions are derived for the detectability parameter of the new test statistics, and it is shown that these statistics are very close to the Gaussian approximation. The improvements obtained in the signal-to-noise ratio and the Gaussian nature of the new statistic implies an improvement in the capacity of the channel by the nonlinear and storage processes involved in the new techniques, something not achievable by linear filtering and/or memoryless detection techniques.
PULMONARY MANIFESTATIONS OF ANKYLOSING SPONDYLITIS AND RELAPSING POLYCHONDRITIS

Ankylosing spondylitis is a chronic inflammatory disease that affects chiefly the joints of the axial skeleton. It is a multisystem disease. Several extra-auricular manifestations of ankylosing spondylitis have been described including ocular, cardiovascular, renal, and neurologic complications. Pulmonary involvement consists principally of upper lobe fibrocystic changes and chest wall restriction. Relapsing polychondritis, on the other hand, is a rare disorder characterized by progressive inflammation and degeneration of the cartilaginous structures and other connective tissues throughout the body. Involvement of the respiratory tract is identified in more than one-half of patients with relapsing polychondritis.
Parametric Study of RC Bridge Columns Actively Confined with Shape Memory Alloy Spirals under Lateral Cyclic Loading

This paper focuses on studying numerically the cyclic behavior of RC bridge columns that are seismically retrofitted using thermally prestressed shape memory alloy (SMA) spirals, an innovative active confinement technique that has been validated experimentally. A fiber-based model of the actively confined column is first developed and is validated using experimental results. Comparing the numerical and experimental behaviors shows that the developed model is satisfactorily capable of describing the hysteretic behavior and damage states of the experimental column. The developed model is then used in a parametric study to investigate the effects of the interactions between active confinement pressure and other important design and geometrical parameters of the columns, such as axial load, volumetric ratio of longitudinal reinforcement, and slenderness ratio. The results of this parametric study provide practical information that is useful in setting a design guideline for retrofitted bridge columns using the newly developed SMA active confinement technique.
Isolation of the active site of cytochrome c by reverse-phase high-performance liquid chromatography

To serve as an introduction to research, an advanced-level graduate laboratory course should be challenging, incorporate currently relevant techniques, offer more responsibility to students, and contain a minimum of technical pitfalls. The following experiment meets all the aforementioned criteria.
Infinite volume, continuum limit of valence approximation hadron masses

Abstract We obtain estimates of several hadron mass ratios, for Wilson quarks in the valence (quenched) approximation, extrapolated to physical quark mass, infinite volume and zero lattice spacing.
Isolation of insect microsomal oxidases by rapid centrifugation

Abstract Only about 60% of the total relative gravitational force conventionally used to sediment microsomes is needed to prepare highly active microsomes from the midgut tissues of an insect larva. A rapid preliminary centrifugation for 2 min at 39,000 g max effectively removed contaminating microorganisms, tissue debris, nuclei, and mitochondria. The supernatant was recentrifuged for 20 min to 210,000 g to sediment the microsomes. There were no losses of microsomal oxidase activities or degradation of cytochrome P -450 to the inactive form ( P -420) resulting from the application of the higher gravitational force. Incorporation of 1 m M EDTA in the buffer and washing the microsomes resulted in an improved yield of the cytochrome compared to that in microsomes prepared in sucrose. Yields of microsomal protein, cytochrome P -450, and NADPH-cytochrome c reductase in the rapidly isolated microsomes were as good as those in conventionally prepared microsomes. The apparent kinetic characteristics of several microsomal oxidation activities and optical difference spectra of Types 1 and 2 ligands were identical in the rapidly and conventionally prepared microsomes. The morphological appearance of the microsomes was examined by electron microscopy. Microsomal pellets prepared by either method were indistinguishable. The rapid procedure saves significant time in microsome preparation and yields microsomal oxidase activities as good or slightly better than those prepared by usual centrifuged procedures.
Bisphosphonate Drug Holidays and Fall Prevention in the Reduction of Postmenopausal Fractures

Bisphosphonates are commonly used as first-line agents in the treatment of postmenopausal bone fragility. Recently, concern has been raised regarding the risk of atypical fracture with long-term therapy. A potential solution to obtaining the benefits while minimizing the risks of bisphosphonate therapy is the use of a drug holiday, or temporary cessation of medication. For drug holidays to be an effective approach, patients must maintain fracture protection while off therapy. One way to optimize fracture protection during this time is to prevent falls. Risk of atypical fracture and bisphosphonate drug holiday will be discussed, along with a summary of the most effective fall prevention modalities.
Comparison of rigid and flexible obturation for surgical cleft of the soft palate.

S urgical removal of tumors in or adjacent to the maxillae is the most common cause of acquired palatal defects.’ As surgical techniques advance, prosthodontic needs advance, and more patients become candidates for maxillofacial reconstruction. In the treatment of soft palate defects, many concepts have been presented since the flap velum was first reported in 177g2 The flap velum attempted only to cover the tissue defect with a mechanical seal in the hope of improving speech and function. At the present time, conventional or rigid obturation similarly involves extending methyl methacrylate resin to the level of greatest muscular activity exhibited by the residual palatopharyngeal complex.3 This prevents leakage of material into the nasal cavity during swallowing and modifies hypernasality during speech. However, as early as 1871 the idea of replacing missing tissue as well as stimulating its physiologic function was presented. The use of unvulcanized rubber had been proposed in 1823 for a soft palate prosthesis.’ Thus we hypothesize that a flexible silicone obturator might better serve the needs of patients with surgically acquired defects of the soft palate. This hypothesis is based on the dynamic changes of the normal soft palate. During speech, the normal soft palate and pharyngeal muscle complex will always be in dynamic equilibrium among the three positions shown4 (Fig. 1). The nasal and oral cavities will be momentarily but perfectly occluded at the positions shown in Fig. l., B, and Fig. 1, C, respectively. These diagrams also represent the position of the soft palate during articulation of consonants and vowels (Fig. 1, B) and nasalized phonemes /m/, /n/, and /ng/ (Fig. 1, C). Would a flexible, silicone obturator be more likely to approximate these positions than the static acrylic resin obturator? Would the patient sound better or worse with the new material? The answers were sought through instrumental and perceptual tests of one rigid and two flexible obturators.
Circadian rhythmicity and photoperiodism in the pitcher-plant mosquito: can the seasonal timer evolve independently of the circadian clock?

Abstract: The two major rhythms of the biosphere are daily and seasonal; the two major adaptations to these rhythms are the circadian clock, mediating daily activities, and the photoperiodic timer, mediating seasonal activities. The mechanistic connection between the circadian clock and the photoperiodic timer remains unresolved. Herein, we show that the rhythmic developmental response to exotic light:dark cycles, usually used to infer a causal connection between the circadian clock and the photoperiodic timer, has evolved independently of the photoperiodic timer in the pitcher‐plant mosquito Wyeomyia smithii across the climatic gradient of eastern North America from Florida to Canada and from the coastal plain to the mountains. We conclude that the photoperiodic timing of seasonal events can evolve independently of the daily circadian clock.
Modeling gaseous dry deposition over regional scales, with satellite observations — II. deriving surface conductances from AVHRR data

Abstract This paper describes methods to couple the reflectance-resistance model developed in Paper I with the normalized difference vegetation index (NDVI) data from the advanced very high resolution radiometer (A VHRR) on satellites over the eastern United States. A land use data set was also employed to determine appropriate model parameters suitable for describing differences in characteristics of light scattering and leaf resistance among different plant canopies, especially between forests and short canopies (crop and grass, etc.). As a case study, the biweekly averaged NDVI data for a year with normal precipitation (1987) and a drought year (1988) were selected for analysis to maximize differences in vegetative conditions and canopy conductance for pollutant transfer. The satellite-derived NDVI over the region had a much lower value in summer 1988 than in summer 1987. The depression was especially large for cultivated areas and rangelands, but it was much less significant for forested regions. The NDVI data were incorporated into the model to calculate the regional distribution of canopy conductances for pollutant transfer to the earth's surface.
Microphase-assisted 'autocatalysis' in a solid-liquid reaction with a precipitating Product - I. Theory

Abstract There are a number of industrially important reactions in which a sparingly soluble solid reacts with a liquid-phase reactant with one of the products precipitating out as a solid. If the particles of the precipitate are in microphase dimensions, i.e. less than the diffusion length of the system, the solubility of the solute is increased by the microphase action of the product in the vicinity of the solid phase. The principal objective of the present work is to describe such ‘autocatalytic’ microphase action by developing a model which simultaneously considers reaction, crystallization, and microphase processes. The chief conclusion is that the growth kinetics and initial crystal size distribution of the precipitating solids have a profound influence on the reaction rate. Earlier models were deficient in that only microphase action was considered with limited effects of nucleation. The theoretical conclusions reported here are sought to be experimentally validated in Part II of this study.
Graphical Notation for Diagramming Coupled Systems

Multiphysics and multiscale---or coupled ---systems share one fundamental requirement: Construction of coupling mechanisms to implement complex data exchanges between a system's constituent models. I have created a graphical schema for describing coupling workflows that is based on a theoretical framework for describing coupled systems. The schema combines an expanded set of traditional flowchart symbols with pictograms representing data states. The data pictograms include distributed mesh, field, and domain decomposition descriptors and spatiotemporal integration and accumulation registers. Communications pictograms include: blocking- and non-blocking point-to-point and M ×N parallel data transfer; parallel data transposes; collective broadcast, scatter, gather, reduction and barrier operators. The transformation pictograms include: intergrid interpolation; spatiotemporal integral operators for accumulation of state and flux data; and weighted merging of output data from multiple source models for input to a destination model. I apply the schema to simple problems illustrating real situations in coupler design and implementation.
Inflation under the Bretton Woods system: The spillover effects of U.S. expansionary policies

This paper examines the transmission effects of U.S. expansionary policies on inflation in the G7 countries under the latter years of the Bretton Woods system. Using quarterly data and structural vector autoregressions, this paper investigates the extent of inflation variability due to U.S. aggregate supply and aggregate demand impulses in major industrial countries. Empirical results show that a sizable proportion of inflation variability in these countries can be attributed to U.S. shocks. A brief discussion follows concerning the breakdown of Bretton Woods and implications for the design and functioning of international monetary arrangements.