cssi/SciSciGPT-SciSciNet huggingface dataset:
Emergence of grain-size effects in nanocrystalline metals from statistical activation of discrete dislocation sources

Abstract Nanocrystalline (NC) metals are exceptionally strong because they contain an unusually high density of grain boundaries (GBs) that act as sources and sinks for dislocations and significantly modify dislocation motion. In this study, we seek to understand the relationship between discrete dislocation emissions from GBs and grain size effects seen in the strength of NC metals. We propose a statistical GB dislocation source model responsible for discrete dislocation slip events. We find that the grain size limitation on dislocation source sizes gives rise to grain size effects on the statistical distribution for the critical resolved shear stress (CRSS) for discrete slip events. To establish its impact on mechanical behavior, this GB source model is integrated into a 3D crystal plasticity finite element model for NC Ni. We observe that a Hall–Petch scaling in yield strength emerges from the calculations. Further the predictions achieve quantitative agreement with experimental data from several studies across a wide range of average nanograin sizes. It is revealed that statistical dispersion in the CRSS for discrete slip events causes (a) strain hardening in the macroscale flow stress–strain response and (b) the fraction of grains that accommodate the applied strain and the fraction of active grains that undergo multi-slip to strongly depend on grain size. It is also found to lead to an unusual texture effect on slip activity that is significant in the finer nanograins but weak in larger grains (>100 nm). In addition, it causes increases in heterogeneity in strain concentrations with decreasing grain size, suggesting that plastic instabilities are more likely to form as nano-scale grain sizes decrease.
Design for a constant volume dispenser of dry adsorbents.

A device which conveniently dispenses small volumes of dry adsorbent materials has been designed. With this device, reproducible volumes of Florisil® are rapidly dispensed into the individual tubes of a typical steroid “competitive protein-binding” assay.
Leveed Channel Deposits, Turbidites, and Contourites in Deeper Part of Gulf of Mexico: ABSTRACT

Several leveed channels can be observed on bathymetric charts from the middle and outer fan of the Mississippi delta apron. Shallow seismic surveys indicate a complexity of shallow channels and associated low levees, although cores show only minor differences between subenvironments. The levees normally contain a higher plant debris content and finer material than the channels. The irregular surface smooths southeastward, and small ripples are present locally on its surface. These deposits are interpreted as contourites; fine sands and silts that are redeposited by deep-water bottom currents. Off the Mississippi delta apron toward the west, the flat abyssal plain is present. The subbottom reflectors are dense and parallel with the surface, the cores indicate a general increase in sand-clay ratio followed by a decrease farther west. The deposits can be interpreted as distal turbidites. Although the variation in aspect and the density of each sedimentary property differs little among the 3 depositional areas, the combination of lithologic alternations, sedimentary structures, high-resolution subbottom profiling, and bottom photography provide information for the development of interpretive models of recent and ancient sediments. End_of_Article - Last_Page 1828------------
Cigarette smoke inhibits recruitment of bone-marrow-derived stem cells to the uterus

Cigarette smoking leads to female infertility and a decreased incidence of endometriosis. Bone marrow derived stem cells are recruited to uterine endometrium and endometriosis. The effect of cigarette smoking on stem cell recruitment to any organ is uncharacterized. We hypothesized that bone marrow-derived mesenchymal stem cell recruitment to the uterus and differentiation would be diminished by cigarette smoke. We used human mesenchymal stem cells (hMSC) in vitro and a mouse model of cigarette smoke exposure. After myeloablation female C57BL/6J received bone marrow cells from males. Mice were exposed to room air or smoke from unfiltered cigarettes. Immunofluorescence and Y-FISH was performed on uterine sections. In vitro hMSCs were treated with 8-Br-cAMP to induce endometrial cell differentiation with or without cigarette smoke extract (CSE) and decidualization assessed morphologically and by prolactin expression. After 4 weeks the total number of Y-chromosome cells in the uterus was reduced by 68% in the smoke exposed mice. Both leukocytes and bone marrow derived endometrial cells were reduced by 60% and 73%, respectively. Differentiation of bone marrow derived cell to endometrial epithelial cells was reduced by 84%. hMSC treated with CSE failed to show cytological characteristics of decidualization. mRNA levels of the decidualization marker prolactin were decreased by 90% in CSE treated cells. Smoking inhibits both recruitment of bone marrow derived stem cells to uterus and stem cell differentiation. Inhibition of stem cells recruitment may be a general mechanism by which smoking leads to long term organ damage through inability to repair or regenerate multiple tissues.
Timing of gonadotrophin and ovarian steroid secretion at diestrus in the rat.

The ovarian steroids responsible for the proestrous rise in uterine weight and release of an ovulatory surge of gonadotrophin and for estrous vaginal cornification appear to be secreted primarily on the day before proestrus (diestrus). To investigate the timing of the gonadotrophin release responsible for this ovarian secretion and for the resultant uterine and vaginal smear changes, rats exposed to light from 5 am to 7 pm and running 3 consecutive 4-day cycles were hypophysectomized at 9 am, 1 pm, 3 pm, or 5 pm on the day of diestrus, and were autopsied at proestrus or estrus. The characteristic rise in uterine weight at proestrus was noted in 0/6 and 1/8 rats hypophysectomized at 9 am and 1 pm, respectively, but in 6/8 and 7/8 rats hypophysectomized at 3 pm and 5 pm. Similarly, hypophysectomy blocked the estrous vaginal cornification when performed at 9 am (0/6) or at 1 pm (0/8), whereas vaginal cornification occurred in 4/6 and 7/7 animals when hypophysectomy was delayed until 3 pm or 5 pm, respectivel...
Ampakines reduce methamphetamine-driven rotation and activate neocortex in a regionally selective fashion

Abstract It has been proposed that glutamatergic and dopaminergic systems are functionally opposed in their regulation of striatal output. The present study tested the effects of drugs that enhance AMPA-receptor-mediated glutamatergic transmission (ampakines) for their effects on dopamine-related alterations in cortical activity and locomotor behavior. Rats with unilateral 6-hydroxydopamine lesions of the ascending nigro-striatal dopamine system were sensitized to methamphetamine and then tested for methamphetamine-induced circling behavior in the presence and absence of ampakines CX546 and CX614. Both ampakines produced rapid, dose-dependent reductions in circling that were evident within 15 min and sustained through 1 h of behavioral testing. In situ hybridization maps of c-fos mRNA expression showed that in the intact hemisphere, ampakine cotreatment markedly increased c- fos expression in parietal, sensori-motor neocortex above that found in rats treated with methamphetamine alone. Ampakine cotreatment did not augment c- fos expression in frontal, sensori-motor cortex or striatum. Still larger ampakine-elicited effects were obtained in parietal cortex of the dopamine-depleted hemisphere where labeling densities were increased by approximately 60% above values found in methamphetamine-alone rats. With these effects, the hemispheric asymmetry of cortical activation was less pronounced in the ampakine-cotreatment group as compared with the methamphetamine-alone group. These results indicate that positive modulation of AMPA-type glutamate receptors 1) can offset behavioral disturbances arising from sensitized dopamine receptors and 2) increases aggregate neuronal activity in a regionally selective manner that is probably dependent upon behavioral demands.
Cell electrophoretic mobility and cationic flux.

The net negativity of the surfaces of Ehrlich ascites cells was reduced by treating them with either neuraminidase or ribonuclease. Neither enzyme treatment affected the Na+ or K+ content of the cells, before or after cooling at 4°C. Experiments with K42 revealed a reduction (9.5 to 17%) in unidirectional K+-fluxes following incubation with neuraminidase, but no change after ribonuclease-treatment. Our data suggest that surface anionic sites associated with RNA and sialic acid moieties are not of major quantitative importance in regulating either intracellular Na+ and K+ concentrations, or unidirectional transmembrane K+-flux. Our results do not enable us to determine whether ion-binding to anionic sites at the electro-kinetic surface is not an essential prerequisite to transmembrane movement, or whether it is essential, but occurs through the 40% of cell surface net negativity which is unaffected by ribonuclease- and neuraminidase-treatment.
Responsibility diffusion and drive enhancement effects on risky shift1

Summary Discussion produced expected risky and cautious shifts on choice dilemma items It was predicted from responsibility diffusion theory that, compared with low-anxious, high-defensive groups, high-anxious, low-defensive groups produce greater risky shift It was predicted from drive enhancement theory that, compared with low-anxious groups, high-anxious groups produce greater risky shift on risk-dominant items and greater cautious shift on caution-dominant items The results of two experiments failed to confirm either interpretation Surprisingly, significant shifts were obtained in a control condition
Robust on-line fault detection diagnosis for HVAC components based on nonlinear state estimation techniques

Abstract This work presents a robust and computationally efficient algorithm for both whole-building and component-level energy fault detection and diagnosis (FDD). The algorithm is able to provide reliable estimation of multiple and simultaneous fault conditions, even in the presence of noisy and sometimes erroneous sensor data, and to provide uncertainty estimation. The algorithm can be used to provide such outputs as the probability of a fault, the likely cause(s), and the expected consequences of the fault(s) on energy use. The approach is based on an advanced Bayesian nonlinear state estimation technique called Unscented Kalman Filtering, but with our addition of a back-smoothing method that provides fast and robust FDD for common building use cases. The approach is presented and demonstrated for detecting energy and hydraulic faults in a chiller plant. The model of the chiller plant is a subsystem of an actual chiller plant, calibrated to real data. The algorithm can detect common faults, such as (1) energy faults (e.g., the chiller is not working properly, or far from its nominal condition), (2) functional faults caused by issues in the compressor and (3) occlusions in the valves that may reduce the water flow rate through the condenser and evaporator water loop. It is also shown that estimates of uncertainty are consistent with the error in the synthetic data, and can be updated as new data stream in from sensors.
A new method for determining the refractive index

A new method has been developed to determine the refractive index of a transparent material. The proposed method utilizes the optical method of transmitted caustics. The new method is simple, accurate and economical. Thin specimens with a central hole, loaded in tension, are used. The results obtained using this technique are compared with the available ones. The percentage difference between the optimum results obtained and the reported value is less than 5 percent.
The clause counter map: an event chaining algorithm for online programmable logic

The clause counter map method (CCM) is a software inference engine for programmable logic systems, including logic controllers and knowledge-based information systems. It provides efficient realizations of synchronous sequential machines using two-valued or three-valued logic. CCM permits the use of general purpose processors for large on-line control models. The CCM interpreter is designed to trade space for time. A redundant state is maintained in a compact map form. Logical events percolate through an otherwise static model. This mode of operation distinguishes the class of event chaining algorithms. Prior on-line methods repeatedly reconstruct or test unchanging portions of the model. In large models, CCM can exceed binary decision machines in speed and require less space. Contemporary modeling languages can be translated into CCM models. Thus event chaining implementation is available for control models defined by relay ladder logic, state machines, function charts, and Petri nets. >
The quantization effects of the CORDIC algorithm

A detailed analysis of the quantization error encountered in the CORDIC (coordinate rotation digital computer) algorithm is presented. Two types of quantization error are examined: an approximation error due to the quantized representation of rotation angles, and a rounding error due to the finite precision representation in both fixed-point and floating-point arithmetic. Tight error bounds for these two types of error are derived. The rounding error due to a scaling (normalization) operation in the CORDIC algorithm is also discussed. An expression for overall quantization error is derived, and several simulation examples are presented. >
Neither Public Nor Private: The Hybridization of Museums

This paper takes a preliminary look at the hybridization of museums – the creation of a variety of mixed forms of governance incorporating both public and private governing authorities. Using data from three national surveys of American museums, the analysis documents the mix of types of governing authority and demonstrates how this mix varies across location, over time, and by museum type. The paper then estimates the extent of hybridization using several different indicators and speculates about its implications. The United States offers a particularly informative case because the general view is that American museums are (1) either public or private and (2) predominately private. While the second part of this view may still be a useful characterization of American museums, the first is no longer a particularly helpful way of understanding American museums, or, by extension, other cultural institutions, American or not. It is increasingly necessary to view cultural institutions through the lens of hybridization rather than privatization in order to improve our ability to document and predict their institutional behavior.
Thermal mangament of multicore processors using power multiplexing

One of the novel methods for the thermal management of multi-core processors is power multiplexing (also known as core hopping) which involves dynamical change of the locations of active cores within the chip at fixed time intervals. The power multiplexing technique helps in reducing the number of hotspots on the chip by providing a spatially uniform thermal profile which in turn lowers the maximum temperature rise on the chip. We quantify the effects of power multiplexing on the thermal profile of multi-core processor chip. Different core migration policies have been implemented in an attempt to evolve an optimally suitable policy for the multiplexing purpose. We observe that the selection of appropriate migration policy and the migration rate can efficiently reduce the spatial non-uniformity and peak temperature on the chip. The ratio of active to total cores has been varied to accommodate and analyze the effect of varying computing workload. We correlated the cooling power with the peak temperature on the chip and discussed the efficient usage of core-migration policies in the context of the power reduction.
Improved bit flipping decoding of low-density parity check codes

In this correspondence, a new method for improving hard-decision bit-flipping decoding of low-density parity-check (LDPC) codes is presented. Bits with a number of unsatisfied check sums larger than a predetermined threshold are flipped with a probability p /spl les/ 1 which is independent of the code considered. The probability p is incremented during decoding according to some rule. With a proper choice of the initial p, the proposed improved bit-flipping (BF) algorithm achieves gain not only in performance, but also in average decoding time for signal-to-noise ratio (SNR) values of interest with respect to p = 1.
INTERSECTION PATTERNS OF ESSENTIAL SURFACES IN 3-MANIFOLDS

Abstract We study the intersection pattern of planes associated to an immersed incompressible surface in a 3-manifold. We establish the finite plane intersection property for immersed incompressible surfaces in certain 3-manifolds. For geometrically finite surfaces in closed, hyperbolic 3-manifolds, we show that there exists a finite cover of the surface cover in which all the sheets are embedded.
fMRI Responses to Video and Point-Light Displays of Moving Humans and Manipulable Objects

We used fMRI to study the organization of brain responses to different types of complex visual motion. In a rapid event-related design, subjects viewed video clips of humans performing different whole-body motions, video clips of manmade manipulable objects (tools) moving with their characteristic natural motion, point-light displays of human whole-body motion, and point-light displays of manipulable objects.The lateral temporal cortex showed strong responses to both moving videos and moving point-light displays, supporting the hypothesis that the lateral temporal cortex is the cortical locus for processing complex visual motion. Within the lateral temporal cortex, we observed segregated responses to different types of motion. The superior temporal sulcus (STS) responded strongly to human videos and human point-light displays, while the middle temporal gyrus (MTG) and the inferior temporal sulcus responded strongly to tool videos and tool point-light displays.In the ventral temporal cortex, the lateral fusiform responded more to human videos than to any other stimulus category while the medial fusiform preferred tool videos. The relatively weak responses observed to point-light displays in the ventral temporal cortex suggests that form, color, and texture (present in video but not point-light displays) are the main contributors to ventral temporal activity. In contrast, in the lateral temporal cortex, the MTG responded as strongly to point-light displays as to videos, suggesting that motion is the key determinant of response in the MTG. Whereas the STS responded strongly to point-light displays, it showed an even larger response to video displays, suggesting that the STS integrates form, color, and motion information.
High-quality inkjet-printed multilevel interconnects and inductive components on plastic for ultra-low-cost RFID applications

In recent years, there has been tremendous interest in all-printed electronics as a means of achieving ultra-low-cost electronic circuits with uses in displays and disposable electronics applications such as RFID tags. While there have been a few demonstrations of printed organic transistors to date, there has been little work on the associated passive component and interconnection technologies required to enable the development of all-printed RFID circuits. In particular, low-resistance conductors are crucial to achieve the high-Q inductors necessary for RFID. Here, we demonstrate inkjetted nanoparticle-Au conductors on plastic with sheet resistances as low as 0.03 ohms/square. We describe the optimization of the jetting parameters, and their impact on final film morphology and electrical properties. We also demonstrate a bridging technology based on an inkjetted polyimide interlevel dielectric. Using this process, we demonstrate multilevel interconnect and passive component structures including conductor patterns, crossover bridges, and tapped planar spiral inductors. Together, these represent an important step towards the realization of all-printed RFID.
Automated Analysis of Ocean Surface Directional Wave Spectra

Abstract To facilitate investigations of surface wave processes in the open ocean, a wave spectral partitioning method with automated swell tracking and storm source identification capabilities has been developed. These tools collectively form the Wave Identification and Tracking System (WITS) and have been assembled entirely within the Matlab programming environment. A series of directional wave spectra, with supporting wind observations, is the only required input. Wave spectrum peaks representing specific wind sea and swell wave systems are extracted based on topographic minima, with wind sea peaks identified by wave age criteria. A swell tracking algorithm, combined with linear wave theory, provides a unique approach to storm source identification using the assimilated wave system statistics. The nature of the partitioned spectra allows the continuous, automated identification and tracking of multiple swell generation areas over space and time. Over a 6-day wave record in the Gulf of Alaska, 44 specif...
Quantitative Leverage Through Qualitative Knowledge: Augmenting the Statistical Analysis of Complex Causes

Social scientific theories frequently posit that multiple causal mechanisms may produce the same outcome. Unfortunately, it is not always possible to observe which mechanism was responsible. For example, IMF scholars conjecture that nations enter IMF agreements both out of economic need and for discretionary domestic political reasons. Typically, though, all we observe is the fact of agreement, not its cause. Partial observability probit models (Poirier 1980, Journal of Econometrics 12:209‐217; Braumoeller 2003, Political Analysis 11:209‐ 233) provide one method for the statistical analysis of such phenomena. Unfortunately, they are often plagued by identification and labeling difficulties. Sometimes, however, qualitative studies of particular cases enlighten us about causes when quantitative studies cannot. We propose exploiting this information to lend additional structure to the partial observability approach. Monte Carlo simulation reveals that by anchoring ‘‘discernible’’ causes for a handful of cases about which we possess qualitative information, we obtain greater efficiency. More important, our method proves reliable at recovering unbiased parameter estimates when the partial observability model fails. The paper concludes with an analysis of the determinants of IMF agreements.
IGF-I promotes a shift in metabolic flux in vascular smooth muscle cells

13C-nuclear magnetic resonance (NMR) spectroscopy was used to test our hypothesis that insulin-like growth factor I (IGF-I) stimulates glucose flux into both nonoxidative and oxidative pathways in vascular smooth muscle cells (VSMC). Rat VSMC were exposed to uniformly labeled [13C]glucose ([U-13C]glucose; 5.5 mM) and [3-13C]pyruvate (1 mM) in the presence and absence of IGF-I (100 ng/ml). IGF-I increased glucose flux through glycolysis and the tricarboxylic acid (TCA) cycle as well as total anaplerotic flux into the TCA cycle. Previous work in our laboratory identified an increase in GLUT1 content and glucose metabolism in neointimal VSMC that was sufficient to promote proliferation and inhibit apoptosis. To test whether IGF-I could potentiate the GLUT1-induced increased flux in the neointima, we utilized VSMC harboring constitutive overexpression of GLUT1. Indeed, IGF-I markedly potentiated the GLUT1-induced increase in glucose flux through glycolysis and the TCA cycle. Taken together, these findings demonstrate that upregulation of glucose transport through either IGF-I or increased GLUT1 content stimulates glucose flux through both nonoxidative and oxidative pathways in VSMC.
An efficient parallel algorithm for accelerating computational protein design.

Motivation: Structure-based computational protein design (SCPR) is an important topic in protein engineering. Under the assumption of a rigid backbone and a finite set of discrete conformations of side-chains, various methods have been proposed to address this problem. A popular method is to combine the dead-end elimination (DEE) and A* tree search algorithms, which provably finds the global minimum energy conformation (GMEC) solution. Results: In this article, we improve the efficiency of computing A* heuristic functions for protein design and propose a variant of A* algorithm in which the search process can be performed on a single GPU in a massively parallel fashion. In addition, we make some efforts to address the memory exceeding problem in A* search. As a result, our enhancements can achieve a significant speedup of the A*-based protein design algorithm by four orders of magnitude on large-scale test data through pre-computation and parallelization, while still maintaining an acceptable memory overhead. We also show that our parallel A* search algorithm could be successfully combined with iMinDEE, a state-of-the-art DEE criterion, for rotamer pruning to further improve SCPR with the consideration of continuous side-chain flexibility. Availability: Our software is available and distributed open-source under the GNU Lesser General License Version 2.1 (GNU, February 1999). The source code can be downloaded from http://www.cs.duke.edu/donaldlab/osprey.php or http://iiis.tsinghua.edu.cn/∼compbio/software.html. Contact: nc.ude.auhgnist@123yjgnez Supplementary information: Supplementary data are available at Bioinformatics online.
Conditional messaging: extending reliable messaging with application conditions

Standard messaging middleware guarantees the delivery of messages to intermediary destinations like message queues, but does not guarantee the receipt or the processing of a message by final recipients. Conditional messaging is an extension to standard messaging middleware that addresses this shortcoming by allowing an application to define, monitor, and evaluate various conditions on messages, such as time constraints on the receipt or the processing of a message by a set of final recipients. In this paper, we introduce the notion of conditional messaging, and present the design and implementation of a flexible and reliable system that supports conditional messaging for use in Java 2 Enterprise Edition and message queuing environments. Our solution uniquely shifts the responsibilities for implementing the management of conditions on messages from the application to the middleware. We further discuss the grouping of multiple conditional messages into atomic units-of-work, which can also integrate requests to transactional resources like distributed objects using object middleware. Conditional messaging serves to implement various kinds of backward dependencies for distributed object transactions that integrate messaging.
¿Influyen el número y volumen de las biopsias pulmonares en el rendimiento diagnóstico en la enfermedad pulmonar intersticial? Análisis mediante índice de propensión

Resumen Introduccion Nuestro objetivo fue evaluar si el numero y el volumen de las biopsias pulmonares quirurgicas (BPQ) influyen en el diagnostico de la enfermedad pulmonar intersticial difusa (EPID). Metodos Estudio retrospectivo de BPQ por sospecha de EPID en los pacientes de la Clinica Mayo desde enero de 2002 hasta enero de 2010. Los datos se recogieron y analizaron en la institucion. Resultados Se analizaron 311 pacientes. El numero medio de biopsias fue de 2,05 (DE 0,6); una biopsia en 50 (16%), dos en 198 (63,7%), tres en 59 (19%) y cuatro en 4 (1,3%). El diagnostico histopatologico fue: definitivo (especifico) en 232 (74,6%), descriptivo (no especifico) en 76 (24,4%) no hubo diagnostico en 3 (1%). Tras excluir a los pacientes sin diagnostico (n = 3), hubo 50 pacientes con solo una biopsia, 196 con dos y 62 con tres o cuatro. El rendimiento de diagnostico definitivo fue similar en los tres grupos (37/50 [74%], 150/196 [77%] y 45/62 [73%]). El valor p de Chi-cuadrado fue 0,8. El analisis del indice de propension entre pacientes con una BPQ y pacientes con mas de una BPQ tampoco mostro ninguna diferencia en el rendimiento diagnostico. En cuanto al volumen de las biopsias, el volumen total medio fue 34,4 cm3 (DE = 46). En los pacientes sin diagnostico, 41,2 cm3 (3 casos), en pacientes con diagnostico especifico, 33,6 cm3 (232 casos [DE = 47]) y en pacientes con un diagnostico descriptivo: 36,6 cm3 (76 pacientes [DE = 44]). El volumen de la biopsia no influyo en el rendimiento de la histopatologia (ANOVA, p = 0,8). Conclusiones El numero o el volumen de las muestras de biopsia quirurgica no parecen influir en el diagnostico. Segun nuestros resultados creemos que una sola muestra de un area representativa puede ser suficiente para el diagnostico. Se deben realizar ensayos prospectivos aleatorizados para optimizar la BPQ en las EPID.
Who, How, and Where Special Education's Issues in Perpetuity

Special education is a product of the nature of human learning and the group orientation of regular education. It will survive or reemerge after the current assault and will continue to confront the chronic issues raised by Deno and Dunn. Professional divisions persist among special educators, and between us and regular educators. Debate continues over the population whom special education “ought” to serve. Individualization remains far more advocated than implemented. The right to an individualized placement decision based on the full continuum of alternative placements is at risk. To save the essential core of the discipline, special education must turn to data, child advocacy, and outcome-based instruction and turn away from slogans, program advocacy, and process-centered approaches.
Neuropsychological Assessment of Battered Women: A Pilot Study:

Mean performance of 19 battered women was significantly lower than that of 9 control women on the Halstead-Reitan Neuropsychological Battery, the Wechsler Memory Scale-Revised, and the Quick Neurological Screening Test. 58% of the battered women scored in the impaired range on the Halstead-Reitan Impairment Index; and 53% scored in the impaired range on the Quick Neurological Screening Test. More definitive research was recommended.
Private Returns, Public Concerns: Addressing Private-Sector Returns in Public–Private Highway Toll Concessions

Governments worldwide face increasing challenges in funding highway infrastructure with public capital. To meet the funding gap, policy makers are turning to public-private concessions for selected projects. These agreements are typically complex, long-term arrangements that entail the private sector agreeing to construct or rehabilitate a public access facility in exchange for rights to future toll revenues or other payments. In exchange for assuming concession risks, the private sector expects a commensurate return. But public procurement officials face real challenges in determining a fair distribution of risks and rewards, as well as in handling the public's perception of such agreements. Placing strict limits on private-sector returns can undermine incentives for construction, financing, and operating efficiencies that are an integral part of the value that can be achieved through public-private concessions. Furthermore, any such limits may not even be effective unless all asupects of a concession th...
Factors affecting the enzymatic hydrolysis of bagasse and rice straw

Abstract This study was initiated to determine the effects of substrate composition, cellulose crystallinity, and particle size on the yields of enzymatic hydrolysis for two agricultural crop wastes, bagasse and rice straw. The data indicate that each individual lignocellulosic substrate requires a specific pretreatment in order to achieve maximum enzymatic hydrolysis. The crystallinity of lignocellulosics may be altered either upward or downward, but does not appear to have a direct relationship in determining susceptibility of the β-1,4-glucosidic bonds to enzymatic hydrolysis. The absolute change in the crystallinity of rice straw following pretreatment did, however, appear to correlate with conversions to either glucose or ethanol. Substrate particle size was determined and found not to be a major factor in enzymtic hydrolysis within the range studied. However, modification of the lignocellulose matrix from its native state by caustic pretreatment resulted in the most significant increases in enzymatic hydrolysis reinforcing the concept that the nature of the native lignocellulose matrix is a major limiting factor in enzymatic hydrolysis of bagasse and rice straw.
Matching, Search, and Heterogeneity

This paper explores the efficiency of decentralized search behavior and matching patterns in a model with ex ante heterogeneity and a constant returns to scale search technology. We show that a linear tax or subsidy on search intensity decentralizes the social optimum. In the absence of the tax, high productivity agents are too willing to match, yet they search too little. Low productivity agents have the opposite behavior. As a result, the equilibrium is always inefficient in the absence of taxes, in contrast to known results on the efficiency of decentralized search models with homogeneous agents. We relate the inefficiencies to thick-market and congestion externalities.
Risk of cardiovascular events associated with positive serology for Chagas: a systematic review

Fourteen included patients with heart failure, six with severe symptoms and nine with mild symptoms or asymptomatic patients with low ejection fraction. In four studies of patients in functional class III or IV and in three studies of patients with mild symptoms, a higher risk of death was reported among those with positive serology for Chagas. Of the 11 studies of patients without symptoms or low ejection fraction, 3 showed a higher risk of mortality related to Chagas exposure. Two of these were based on the same cohort of people aged 460 years. Overall, 8 out of the 14 heart failure studies and 2 out of the 11 heart damage studies adjusted for confounding factors. Conclusion Positive serology for Chagas is associated with a higher risk of death for patients with heart failure. However, there is little evidence to link positive serology for Chagas with cardiovascular events in asymptomatic subjects.
Barbiturate Protection From Cerebral Infarction in Primates

Baboons were anesthetized with halothane or pentobarbital prior to middle cerebral artery (MCA) occlusion to test the protective effect of barbiturates against stroke in primates. Significantly less infarction was found in animals that received 90 mg per kilogram pentobarbital or more than occurred in control animals. Because of cardiovascular and ventilatory complications at high doses of barbiturate, however, therapeutic trials to suppress stroke in the human must await further identification of an effective regimen which includes a safe barbiturate dose.
Multiple repeat prostate biopsies and the detection of clinically insignificant cancer in men with large prostates.

Objective To determine the impact of repeating prostate biopsies on the risk of detecting clinically insignificant prostate cancer (PCa) in larger prostate glands. Methods We performed a retrospective cohort study using patients enrolled in our institutional PCa registry from 1991 to 2008 to assess the association of prostate volume and clinically insignificant PCa in men undergoing multiple prostate biopsies. Patients were stratified by prostate volume into 2 cohorts ( 3 or ≥50 cm 3 ). Additionally, patients were stratified by prostate biopsy on which PCa was identified (1 biopsy or ≥3 biopsies). Results Within the subgroup of patients with prostate volume ≥50 cm 3 requiring ≥3 biopsies before cancer diagnosis, 72.6% (45/62) had pathologic Gleason scores ≤6 and 81.6% (49/60) had an estimated tumor volume of ≤10% at the time of radical prostatectomy. This was significantly different from patients with prostate volume 3 diagnosed on their first biopsy, in which only 48.5% (656/1349) were found to have Gleason scores ≤6 and 54.2% (705/1300) had estimated tumor volume ≤10% ( P Conclusion PCas detected in men with prostatic enlargement requiring multiple biopsies are more likely to be low-grade, low-volume tumors at final pathology than men without prostate enlargement. Men with larger prostates who have already had prior negative biopsies should be counseled regarding the increased risk of detecting clinically insignificant PCa with additional biopsies.
Renal artery interventions during infrarenal endovascular aortic repair: a greater potential of subsequent failure?

Purpose To determine the anatomic and functional outcomes of renal artery interventions during endovascular aortic aneurysm repair (EVAR) and compare them with renal artery interventions without EVAR. Materials and Methods A renal artery revascularization database (1987–2007) was reviewed to identify patients who underwent renal intervention during EVAR and those who had an intervention in the absence of EVAR. Outcomes were analyzed with respect to patient comorbidities, renal anatomy and function, procedural events, and postoperative complications. Results A total of 413 patients (239 men; 58%) underwent 589 renal artery revascularizations (51 with EVAR and 362 without). Mean age was 70 years ± 10. Mean follow-up was 3.5 years (range, 1–13 y). Primary indications for renal intervention were hypertension (63%) and elevated creatinine level (27%). The EVAR group was more likely to incur an increased creatinine level at 1 month after intervention (33% vs 18%; P = .007). Freedom from restenosis was similar ( P = .501), but arterial occlusion rate was higher in the EVAR group (96% ± 3% vs 100% ± 10% cumulative patency at 3 y; P = .005). At 3 years, freedom from recurrent symptoms ( P = .26), freedom from adverse renal events ( P = .12), and survival (85% ± 8% vs 75% ± 2%; P = .83) were not significantly different. Conclusions Renal artery revascularization during EVAR should be considered higher risk because of the high incidence of procedural complications, early functional injury, and early occlusion rates. However, the long-term sequelae and benefits of such a procedure are similar to those of a renal revascularization procedure in the absence of EVAR.
Moving Beyond the Heritability Question: New Directions in Behavioral Genetic Studies of Personality

50% of the variability of personal ity within a population. The find ing of genetic influences on person ality has been replicated across American, Australian, British, Finnish, Swedish, and Russian cul tures. However, the conclusion that individual differences in per sonality are, in part, due to genetic factors is just the beginning of the story. Behavioral genetics has much more to offer to the study of personality than heritability esti mates, and in this article, I describe three exciting new directions that behavioral genetic studies of per sonality are taking. Although basic behavioral genetic terms are de fined, details of the theory and methods cannot be described in
An Evaluation of the San Francisco Department of Human Services Welfare Dental Program

Objective: To evaluate the welfare-to-work San Francisco Personal Assisted Employment Services (PAES) Dental Program. Methods: A cohort of 377 study participants in the novel PAES Dental Program were followed through their baseline examination, rehabilitative dental treatment, follow-up exam, and completion of patient satisfaction survey. A framework of structure, process, and outcome measures was used to evaluate the success of the Dental Program. Chi square test, logistic regression, and paired t-test were used to analyze the levels of participation and satisfaction in the program. Results: Of the 377 study participants, 265 (70%) completed their rehabilitative dental treatment. Those who completed their dental treatment had more missing teeth and fewer decayed teeth at baseline than those who did not complete their treatment. High levels of patient satisfaction were reported for the Dental Program. Ninety-seven percent of 173 respondents felt that they had been treated with respect, 92% were satisfied with the scheduling of their appointments, 91% were satisfied with their Dental Program experience, and 90% felt that their chief complaint had been solved. Conclusion: The PAES Dental Program provided high levels of patient satisfaction for process and outcome measures.
Factors Affecting Patient Radiation Exposure During Percutaneous Nephrolithotomy

Purpose: We identified patient and stone characteristics that may contribute to increased radiation exposure during percutaneous nephrolithotomy and offer technique modifications to limit the radiation dose.Material and Methods: We reviewed the records of 96 patients who underwent percutaneous nephrolithotomy in the last 2 years. The effective radiation dose was calculated using accepted conversion tables. We performed multivariate linear regression to determine the association of the effective radiation dose with specific patient, stone and procedural characteristics.Results: Mean ± SD patient age was 51.5 ± 13.4 years and 62.5% of the patients were female. Median body mass index was 32.0 ± 9.7 kg/m2 (range 16.2 to 59.6) and the median stone burden was 4 cm2. Increased body mass index (p <0.001), higher stone burden (p = 0.013), stone nonbranched configuration (p = 0.002) and a greater number of percutaneous access tracts (p = 0.040) were significantly associated with an increased effective radiation dos...
Using E-Maps to Organize and Navigate Web-based Content

Many university faculty create their own websites or use a course management system to upload course materials for online instruction. Course content and files are mostly organized and presented in a linear structure and placed in a series of folders and subfolders. An alternative approach to navigate, organize, and sequence Webbased content is to use a computer generated mind map – an E-Map. With its unique storage and organizational capacity, E-Maps not only provide a user-friendly elearning structure, but also can effectively manage knowledge in a much more efficient manner than using a linear approach to navigate and access Web-based content. The purpose of this article is to examine how E-Maps can be used as a graphical interface for presenting and organizing Web-based course content and files online. Explored in this article is a brief overview of mind maps , mind mapping software, how using E-Maps as a graphic organizer can facilitate learning, and some instructional application examples of using E-Maps for Web-based instruction.
A generating function approach to the stability of discrete-time switched linear systems

Exponential stability of switched linear systems under both arbitrary and proper switching is studied through two suitably defined families of functions called the strong and the weak generating functions. Various properties of the generating functions are established. It is found that the radii of convergence of the generating functions characterize the exponential growth rate of the trajectories of the switched linear systems. In particular, necessary and sufficient conditions for the exponential stability of the systems are derived based on these radii of convergence. Numerical algorithms for computing estimates of the generating functions are proposed and examples are presented for illustration purpose.
Advanced imaging use in intensive care units has decreased, resulting in lower charges without negative effects on patient outcomes.

Abstract Purpose There has been both greater recognition and scrutiny of the increased use of advanced imaging. Our aim was to determine whether there has been a change over time in the use of computed tomography (CT), magnetic resonance imaging (MRI), ultrasound (US) modalities in the intensive care units (ICUs). Materials and Methods A retrospective review of 75657 admissions to 20 ICUs was conducted. Results were analyzed with multivariate linear, negative binomial, and Poisson regressions. Primary outcomes were rates of use of CT, MRI, and US per 1000 ICU admissions every 6 months. Secondary outcomes were changes in radiology use associated with impacts on mortality, hospital length of stay (LOS), ICU LOS, and hospital charges. Results The rate of imaging use decreased by 13.5% between 2007 and 2011 (incidence rate ratio [IRR], 0.982; P P P = .04), whereas US increased by 18.9% (IRR, 1.012; P Conclusion Advanced imaging use decreased for 5 years in the ICUs, resulting in decreased charges without negative effects on patient outcomes.
Nonmedical Opioid Pain Relievers and All-Cause Mortality: A 27-Year Follow-Up From the Epidemiologic Catchment Area Study

Objectives. We investigated whether nonmedical opioid pain reliever use is associated with higher mortality in the general US population.Methods. We assessed the history of nonmedical opioid pain reliever use among 9985 people interviewed at baseline of the Epidemiologic Catchment Area Program initiated in 1981 to 1983 in Baltimore, Maryland; St. Louis, Missouri; and Durham, North Carolina. We linked the data with the National Death Index through 2007.Results. Nonmedical opioid pain reliever use was 1.4%. Compared with no nonmedical drug use, mortality was increased for nonmedical opioid pain reliever use (hazard ratio [HR] = 1.60; 95% confidence interval [CI] = 1.01, 2.53) or nonmedical use of other drugs (HR = 1.31; 95% CI = 1.07, 1.62). Mortality was also higher for males and for those beginning nonmedical opioid pain reliever use before aged 15 years.Conclusions. A history of nonmedical opioid pain reliever use was associated with increased mortality, in particular for males and early onset users.
Conducting polymers and their biomedical applications

Abstract Conducting polymers have been widely utilised in biomedical applications due to their conductivity, compatibility and low-cost processability. In addition, compared with traditional metal or semiconductor materials, conducting polymers are more biocompatible. These advantages make conducting polymers more attractive to bioengineering researchers. The mechanism of electrical conductivity of conducting polymers is based on the transmission of polarons and bipolarons. The synthesis of conducting polymers can be accomplished by electrochemical polymerisation, which is more straightforward than traditional chemical synthesis. In this chapter, several applications of conducting polymers in biomedical engineering are illustrated with examples. The applications include biosensors, neural electrodes, drug delivery and bioactuators.