cssi/SciSciGPT-SciSciNet huggingface dataset:
Pattern separability and the effect of the number of connections in a random neural net with inhibitory connections

It has been claimed that pattern separation in cerebellar cortex plays an important role in controlling movements and balance for vertebrates. A number of the neural models for cerebellar cortex have been proposed and their pattern separability has been analyzed. These results, however, only explain a part of pattern separability in random neural nets. The present paper is intended to study an extended theory of pattern separability in a new model with inhibitory connections. In addition to this, the effect of the number of connections on pattern separability is cleared up. It is also shown that the signal from the inhibitory connections has crucial importance for pattern separability.
Newspaper Recycling: The Effects of Rewards and Proximity of Containers

Newspaper recycling, if widely practiced, could contribute to the conservation of natural resources and energy. Two experiments using multiple baseline designs with reversals were conducted to inve...
Controlling stock externalities in a common property fishery subject to uncertainty

Abstract Two methods are examined for regulating stock externalities under uncertainty: quotas and taxes. Dynamic programming is used to characterize the externalities precisely. The accuracy with which the current size of the resource stock can be monitored is found to be of crucial importance in the choice between tax and quota regulation. If the current stock is observed without error, taxes are capable of outperforming any quota.
Bradykinin and vasoconstriction in the perfused rat liver.

SummaryBradykinin administered intraportally produced transient decreases in flow in isolated rat livers perfused at constant pressure with either homologous blood or a balanced salt solution. The minimal effective dose of bradykinin in blood-perfused preparation was 0.5 μg; maximal effects were achieved with 25.0 μg. Flow decreases induced by bradykinin were greater in blood-perfused livers than in livers perfused with a balanced salt solution. Tachyphylaxis was demonstrated by the inability of a second bradykinin dose to produce prominent effects until 30 min after an initial vasoconstrictor dose.
Genetics of Hearing and Deafness

This article is a review of the genes and genetic disorders that affect hearing in humans and a few selected mouse models of deafness. Genetics is playing an increasingly critical role in the practice of medicine. This is not only in part to the importance that genetic knowledge has on traditional genetic diseases but also in part to the fact that genetic knowledge provides an understanding of the fundamental biological process of most diseases. The proteins coded by the genes related to hearing loss (HL) are involved in many functions in the ear, such as cochlear fluid homeostasis, ionic channels, stereocilia morphology and function, synaptic transmission, gene regulation, and others. Mouse models play a crucial role in understanding of the pathogenesis associated with these genes. Different types of familial HL have been recognized for years; however, in the last two decades, there has been tremendous progress in the discovery of gene mutations that cause deafness. Most of the cases of genetic deafness recognized today are monogenic disorders that can be broadly classified by the mode of inheritance (i.e., autosomal dominant, autosomal recessive, X-linked, and mitochondrial inheritance) and by the presence of associated phenotypic features (i.e., syndromic; and nonsyndromic). In terms of nonsyndromic HL, the chromosomal locations are currently known for ∼ 125 loci (54 for dominant and 71 for recessive deafness), 64 genes have been identified (24 for dominant and 40 for recessive deafness), and there are many more loci for syndromic deafness and X-linked and mitochondrial DNA disorders (http://hereditaryhearingloss.org). Thus, today's clinician must understand the science of medical genetics as this knowledge can lead to more effective disease diagnosis, counseling, treatment, and prevention.
Analysis of worldwide regulatory guidance values for the most commonly regulated elemental surface soil contamination

Guidance values are used worldwide to regulate exposure to surface soil contamination. This analysis examines values applied to element contamination. In the United States, element guidance values have been promulgated by at least 6 federal agencies, 46 states and several regional, city, county, territorial, and autonomous Native American jurisdictions. Guidance values have also been promulgated in at least 71 other United Nations member states. A total of 5949 guidance values for 57 elements have been identified. These values are characterized, and detailed analyses are provided for the eight most frequently regulated elements (Pb, Cd, As, Ni, Cr, Hg, Cu, and Zn). More than 300 guidance values available for each of these are tabulated. These values span from 3.6 orders of magnitude for lead to 6.9 orders of magnitude for arsenic and are distributed in patterns that resemble those of lognormal random variables. However, nonrandom value clusters are also identified in each distribution. On average, the values used in the U.S. are higher than those used elsewhere around the world for noncarcinogenic contaminants, but are lower for carcinogenic contaminants. Approximately 31.4% of all values fall within uncertainty bounds computed from the U.S. Environmental Protection Agency cancer or noncancer risk model, but only 12.9% of carcinogenic arsenic and 7.5% of carcinogenic chromium (Cr-VI) guidance values fall within cancer risk model uncertainty bounds.
Evidence for predatory flatworms as organizers of zooplankton and mosquito community structure in rice fields

I present evidence from two field studies and one laboratory experiment that the predatory flatworm, tentatively indentified as Mesostoma nr. lingua, can be important in organizing invertebrate communities in rice fields. In the first field study, I assessed the importance of various predators including two fishes, in explaining among-plot variation in mosquito abundance during a five week interval. Mosquitofish (Gambusia affinis) abundance was not significantly associated with densities of either mosquito, Culex tarsalis or Anopheles freeborni, except for the final week. Associations between green sunfish (Lepomis cyanellus) juveniles and mosquitoes were demonstrated for only A. freeborni — a positive association. Densities of Mesostoma were negatively associated with C. tarsalis and A. freeborni densities. C. tarsalis, protected from flatworms in small-mesh cages, had a much greater survival rate than those that were exposed in large-mesh cages. C. tarsalis survival, when left unprotected in large-mesh cages, was negatively correlated with field densities of flatworms and with the number of flatworms found inside the cages. Survival was also positively correlated with field densities of mosquitoes. In the second field study, Mesostoma densities were negatively correlated with C. tarsalis, A. freeborni, Cladocera and Ostracoda in rice field enclosures early in the season. Cyclopoid copepod densities were not significantly associated with this predator. In a laboratory experiment, predation by Mesostoma on C. tarsalis larvae was reduced when presented with an alternative prey, Moina micrura (a cladoceran). These results suggest that flatworms, via predation, can have large effects on the structure of mosquito and zooplankton communities in rice fields.
Refractometric determination of second‐order transition temperatures in polymers. V. Determination of the refractive indices of elastomers at temperatures from 25 to −120°C

Abstract In previous papers a refractometric method was described for determining second-order transition temperatures of polymers whose transitions occur between 75 and −60° C. In the present study, an Abbe refractometer was insulated and used to determine the refractive indexes of polymers down to − 120° C and the transition points of natural rubber and a number of synthetic rubbers.
Interventions based on the multiple connections model of reading for developmental dyslexia and acquired deep dyslexia

This paper deals with intervention strategies for developmental and acquired dyslexia. In Study 1 two alternative strategies for developmental surface dyslexia (dysfunctional connection between the whole word orthographic code and the phonetic or name code) were compared. In both the initial study and replication study, a modification of the selective reminding technique was superior to a traditional multisensory technique in beginning readers, presumably because it facilitated word finding or prelexical access to a phonetic code. In Study 2 an adolescent with acquired deep dyslexia (dysfunctional connection between letter and phonemic codes) who had had his angular gyrus (site of grapheme-phoneme correspondence) surgically removed, recovered reading function after a four-month phonemic analysis training program. Further research is needed to evaluate the efficacy of theory-based intervention strategies in children with developmental reading disorders unrelated to focal lesions and in adults with acquired reading disorders related to focal lesions.
Cardiovascular response to Crotalus venom

The intravenous injection of Crotalus atrox venom produces an immediate and profound fall in systemic arterial pressure. This change was observed in both cats and dogs, and it has been seen in previous experiments with rabbits, goats, guinea pigs and monkeys. In the cat, the hypotensive crisis does not appear to be due to a decrease in heart rate or contractile force, although even small amounts of the venom may elicit cardiac changes. It is not due to a deficit in venous return, depression of the central nervous system, sudden electrolytic imbalance, pooling of blood in the portal or peripheral vascular systems, or a decrease in the total blood volume. While certain changes occur in peripheral resistances, the initiating response appears to take place in the pulmonary circulation. The rapidity of the response would seem to indicate that the changes in the cardiopulmonary vascular system might be due to the direct action of the venom on this system, but the data do not preclude the possibility that the initial response is an autopharmacological one provoked by the venom.
Phase-specific elastic/plastic interface interactions in layered NiAl-Cr(Mo) structures

Abstract The depth-dependent, as-grown and deformation-induced strain and dislocations partitioned through the interfaces in a two-phase layered NiAl–Cr(Mo) structure are directly measured at the mesoscale using 3-D X-ray microdiffraction. It is demonstrated that in the as-grown, undeformed state, neighboring submicron Cr solid solution and NiAl eutectic lamellae (doped with ∼3% Mo) form a heterointerface with 180° rotation around a 〈1 1 2〉 pole. It is shown that the mechanical response to the indentation of a layered composite with alternating Cr(Mo)–NiAl lamellae is distinct from the response of single-phase materials. In the center of the indent, after the load is released, the NiAl lamellae are under compressive forward stresses (with the same sign as the indentation-induced compression) while Cr solid solution lamellae are under tensile back stresses (with opposite sign from the indentation load). The depth-dependent alternation of compressive/tensile residual strains in the neighboring Cr solid solution and NiAl lamellae is understood in the framework of the Mughrabi’s composite model considering two types of structure elements: harder and softer regions. Under indentation, both kinds of lamellae are assumed to deform compatibly. After the load is released, residual forward stresses are formed in the harder lamellae, and back stresses are formed in the mechanically softer lamellae. Line-broadening analysis of the intensity distribution along the diffraction vector reveals a 15-times increase in dislocation density in the near-surface zone in the center of the indent. Such a large increase is typical for severe deformation.
The impact of cognitive behavioral group training on event-free survival in patients with myocardial infarction: The ENRICHD experience

Abstract Objective Although the Enhancing Recovery in Coronary Heart Disease (ENRICHD) treatment was designed to include individual therapy and cognitive behavioral group training for patients with depression and/or low perceived social support, only 31% of treated participants received group training. Secondary analyses classified intervention participants into two subgroups, (1) individual therapy only or (2) group training (i.e., coping skills training) plus individual therapy, to determine whether medical outcomes differed in participants who received the combination of group training and individual therapy compared to participants who received individual therapy only or usual care. Methods Secondary analyses of 1243 usual care, 781 individual therapy only, and 356 group plus individual therapy myocardial infarction (MI) patients were performed. Depression was diagnosed using modified Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) criteria; low perceived social support was determined by the ENRICHD Social Support Instrument. Psychosocial treatment followed MI, and for participants with severe or unremitting depression, was supplemented with a selective serotonin reuptake inhibitor. Cox proportional hazards regression was used to estimate intervention effects on time to first occurrence of the composite end point of death plus nonfatal MI. To control for confounding of group participation with survival (because individual sessions preceded group), we used risk set sampling to match minimal survival time of those receiving or not receiving group training. Results Analyses correcting for differential survival among comparison groups showed that group plus individual therapy was associated with a 33% reduction (hazard ratio=0.67; 95% confidence interval, 0.49–0.92, P =.01) in medical outcome compared to usual care. No significant effect on event-free survival was associated with individual therapy alone. The group training benefit was reduced to 23% (hazard ratio=0.77; 95% confidence interval: 0.56–1.07, P =.11) in the multivariate-adjusted model. Conclusions Findings suggest that adding group training to individual therapy may be associated with reduction in the composite end point. A randomized controlled trial is warranted to definitively resolve this issue.
Apparatus and technique for work with the curarized rat.

Apparatus for respirating the curarized rat is described. Important variables in obtaining a stable curarized rat preparation are the volume and pressure of air with which the animal is respirated. Heart rate is a convenient indicator of the adequacy of respiration and a bleed valve added to the respirator allows fine volume adjustments which result in a stable, moderate level HR of 350-420 bpm and a variability of 20-40 bpm. It is also important to keep the animal at a steady depth of curarization, and maintain adequate body temperature.
First trimester of pregnancy laparoscopic procedures

Laparoscopic procedures are being performed during pregnancy with increasing frequency; however, few first-trimester operations have been published. Two first-trimester procedures are here reported, both performed with uneventful recoveries.
A RANDOMIZED CONTROLLED STUDY OF POST-INJECTION REST FOLLOWING INTRA-ARTICULAR STEROID THERAPY FOR KNEE SYNOVITIS

In order to assess the effect of 24 h observed bed rest following intra-articular steroid injection of the knee joint in patients with an inflammatory arthritis such as RA, AS or colitic arthropathy, 91 patients with inflammatory arthritis of one knee joint were randomized to receive 24 h bed rest in hospital following intra-articular steroid injection or were injected in outpatients. The clinical and laboratory assessments such as pain and stiffness on a 10-cm visual analogue scale, knee circumference (cm), 50 ft walking time (s), CRP and ESR were measured before receiving the steroid injection and at 3, 6, 12 and 24 weeks. Both groups of patients improved clinically and serologically at 3 weeks. By 12 weeks the degree of improvement in the pain score, stiffness score, knee circumference, 50 ft walking time and CRP was better in the rest group and these differences persisted to 24 weeks. For each outcome variable the summary measure of response was significantly better in the rest group compared to the no rest group. Intra-articular steroid injection of the knee joint followed by strict i inpatient bed rest for 24 h results in a greater degree of clinical and serological improvement, compared to routine outpatient injections for up to 6 months. It is therefore possible that 24-h post-injection rest will result in a prolonged duration of clinical response and reduce the need for frequent steroid injections and the risk of complications.
Minorities Are Less Likely to Receive Autologous Blood Transfusion for Major Elective Orthopaedic Surgery

Background Surgeons commonly arrange for patients to perform autologous blood donation before elective orthopaedic surgery. Understanding sociodemographic patterns of use of autologous blood transfusion can help improve quality of care and cost containment.
Cyclic Queuing Systems with Restricted Length Queues

This paper is concerned with an analysis of the stochastic behavior of a system of tandem queuing stations in which capacity restrictions are imposed on the queue lengths. The closed, cyclic systems that we consider are shown to be stochastically equivalent to open systems in which the number of customers is a random variable. A concept of duality is introduced on the basis of the simple observation that the sequential movement of customers through the stages generates a counter-sequential motion of "holes." The implications of the duality relation are discussed at some length. The differential-difference equations for the time-dependent stochastic structure of the system are derived, and the remainder of the paper is devoted to the solution of the equilibrium equations for several special systems. First, we analyze completely systems with only two stages. The well-known results for a finite capacity queue appear as a special case. Next, systems are considered for which the number of customers is so small that there is no possibility of blocking. Then, by a duality argument, an analysis is carried out for systems with a very large number of customers in which the blocking effect dominates. Finally, we compare two extreme systems. In the one system there is no blocking and customers may queue at each stage. The other system has unit capacity at each of the M stages so that the distribution of customers is determined solely by the effect of blocking.
Root growth and function of three Mojave Desert grasses in response to elevated atmospheric CO2 concentration

Root growth and physiological responses to elevated CO2 were investigated for three important Mojave Desert grasses: the C3 perennial Achnatherum hymenoides, the C4 perennial Pleuraphis rigida and the C3 annual Bromus madritensis ssp. rubens. Seeds of each species were grown at ambient (360 μl l−1) or elevated (1000 μl l−1) CO2 in a glasshouse and harvested at three phenological stages: vegetative, anthesis and seed fill. Because P. rigida did not flower during the course of this study, harvests for this species represent three vegetative stages. Primary productivity was increased in both C3 grasses in response to elevated CO2 (40 and 19% for A. hymenoides and B. rubens, respectively), but root biomass increased only in the C3 perennial grass. Neither above-ground nor below-ground biomass of the C4 perennial grass was significantly affected by the CO2 treatment. Elevated CO2 did not significantly affect root surface area for any species. Total plant nitrogen was also not statistically different between CO2 treatments for any species, indicating no enhanced uptake of N under elevated CO2. Physiological uptake capacities for NO3 and NH4 were not affected by the CO2 treatment during the second harvest; measurements were not made for the first harvest. However, at the third harvest uptake capacity was significantly decreased in response to elevated CO2 for at least one N form in each species. NO3 uptake rates were lower in A. hymenoides and P. rigida, and NH4 uptake rates were lower in B. rubens at elevated CO2. Nitrogen uptake on a whole root-system basis (NO3+NH4 uptake capacity × root biomass) was influenced positively by elevated CO2 only for A. hymenoides after anthesis. These results suggest that elevated CO2 may result in a competitive advantage for A. hymenoides relative to species that do not increase root-system N uptake capacity. Root respiration measurements normalized to 20 °C were not significantly affected by the CO2 treatment. However, specific root respiration was significantly correlated with either root C[ratio ]N ratio or root water content when all data per species were included within a simple regression model. The results of this study provide little evidence for up-regulation of root physiology in response to elevated CO2 and indicate that root biomass responses to CO2 are species-specific.
Versatile photonic crystal fiber-enabled source for multi-modality biophotonic imaging beyond conventional multiphoton microscopy

In a typical multiphoton microscope, the majority of the laser power from the near-IR pulsed source is thrown away in order to prevent photo-damage on biological samples. It is thus desirable to convert this wasted power into other wavelengths through nonlinear fiber optics to accommodate imaging modalities beyond conventional multiphoton microscopy. Here we present a prototypical source that accommodates the requirements for laser scanning confocal microscopy, fluorescence lifetime imaging microscopy, stimulated emission microscopy, coherent anti-Stokes Raman microscopy/spectroscopy, transient absorption microscopy, and optical coherence tomography/microscopy. Such versatile source consists of dispersion-engineered photonic crystal fibers simultaneously pumped by a compact ~1040 nm ultrafast ytterbium laser.
Reliability of low-cost CdS/Cu2S solar cells

Accelerated life tests show that CdS/Cu2S solar-cell lifetimes increase with lower temperature, cyclic light and a nitrogen-gas ambient. A normal Arrhenius type of temperature dependence was found. Extrapolated lifetime for cells kept below 50°C in nitrogen gas with earth deployment exceeded twenty years. The probable decay mechanisms are thermal diffusion, formation of recombination centres and voltage-induced decomposition.
Games, covering properties and Eberlein compacts

Abstract Consider the following game played in a locally compact space X: at the nth move, K chooses a compact set Kn⊂X, and then P chooses a point pn∉∪{Ki: i⩽n}. We say K wins ifP's points have no limit point in X. We show that X is metacompact (σ-metacompact) if and only if K has a strategy in this game which depends only on P's last move (and the number of the move). As a corollary we obtain a game characterization of Eberlein compact spaces. We also show that if P is allowed to choose compact sets instead of points, then K has a winning strategy if and only if X is paracompact.
Ballistic magnetoresistance over 3000% in Ni nanocontacts at room temperature

This paper reports ballistic magnetoresistance (BMR) measurements in Ni nanocontacts made by electrodeposition. BMR in excess of 3000% is observed at room temperature and the observed large values of BMR are obtained in switching fields of only a few hundred oersteds. The results are attributed to spin-dependent electron transport across nanometer sharp domain walls within the nanocontacts.
Perceived disadvantages and concerns about abuses of genetic testing for cancer risk: differences across African American, Latina and Caucasian women

Participation in genetic testing for cancer risk is low among women of medically underserved ethnic groups and this is due, in part, to genetic testing attitudes, specifically perceived disadvantages of genetic testing and concerns about possible abuses of genetic testing. The goals of the current study were to: (a) explore genetic testing attitudes, and (b) determine the extent to which ethnicity, awareness of genetic testing, and medical mistrust are associated with genetic testing attitudes. African American, Latina, and Caucasian women (N=273) completed an interview assessing sociodemographic information, genetic testing awareness, medical mistrust, and genetic testing attitudes. Latina participants more strongly agreed with disadvantages of testing than the other ethnic groups. Both Latina and African American women more strongly concurred with concerns about testing abuses compared to Caucasian women. In hierarchical linear regression analyses, Spanish language preference and medical mistrust were the only significant predictors of perceived disadvantages and medical mistrust was the only significant predictor of abuse concerns. These findings support the importance of identifying genetic testing attitudes that may be culturally specific in order to promote culturally competent care by genetic risk professionals.
Exotica: a project on advanced transaction management and workflow systems

This paper is an overview of the Exotica project, currently in progress at the IBM Almaden Research Center. The project aims at exploring several research areas from advanced transaction management concepts to client/server architectures and mobile computing within the context of business processes and workflow management. The ultimate goal is to incorporate these ideas into IBM's products and prototypes. The project involves IBM groups in Almaden (U.S.A.), Hursley (U.K.), Boeblingen (Germany), and Vienna (Austria). In this paper we briefly describe two IBM products, FlowMark, a workflow management system, and MQSeries, a messaging system, as the environments in which we are focusing our research. We also discuss some of our results in the areas of availability, replication, distribution, and advanced transaction models, as well as describe our future research directions. 10
Four Cases of Congenital Portacaval Shunt in the Dog

Four cases of congenital portacaval shunt in the dog are presented. The variable clinical signs, diagnostic clinical pathology and radiology, and therapy are discussed.
Drag reduction in polymer mixtures and the effect of molecular weight distribution

SMALL amounts of certain high molecular weight polymers can reduce the frictional drag in turbulent flow through pipes1,2. Although the phenomenon—the so-called drag reduction effect—has been studied extensively, very little information is available about the effects of molecular weight distribution in polydisperse samples. All common drag reducing agents are characterised by a broad distribution of molecular weights, which changes during shear degradation3,4. Consequently, any molecular theory of drag reduction must include some means of handling these complications. The equations presented here represent a possible first step in this direction.
Against giants or windmills? The struggle for the human genome

In the book review by David J. Galas [TIBS (2002) 27, 324–325], the book details should have read The Common Thread: A Story of Science, Politics, Ethics and the Human Genome by John Sulston and Georgina Ferry. Bantam Press, 2002. £17.99 (310 pages) ISBN 0 593 04801 6. TiBS apologizes for any confusion caused by this error.
Resting Traces of Ocypode quadrata Associated with Hydration and Respiration: Sapelo Island, Georgia, USA

This report adds resting traces to the behavioral suite of traces made by the modern ghost crab Ocypode quadrata, but with emphasis on their association with hydration and respiration in intertidal environments. Resting traces were observed on sandy upper shoreface surfaces of Sapelo Island (Georgia, USA) immediately after high tide. The best preserved of these traces were impressions of the ventral anatomy of O. quadrata that connected with trackways, the latter indicating movement of tracemakers away from body impressions. Crabs formed the traces by moving from the upper shoreface to the surf zone to rehydrate their gills, which they facilitated by settling into saturated sands following high tide. Ventral surfaces of crabs compacted sediments sufficiently to form body and leg impressions. An ebbing of the tide and corresponding drainage of pore water caused the best-preserved traces. Later observations of this behavior in O. quadrata confirmed the ichnological interpretations. The ichnological signific...
Robust estimation techniques in regularized image restoration

The performance of conventional restoration algorithms is highly degraded by the presence of outliers in the nominal noise process. A novel restoration approach that combines the properties of regularized and robust estimation schemes is introduced. Moreover, we address the potential of robust stabilizing functionals in preserving the detailed structure. Initially, the least-squares part of the regularized optimization scheme is modified according to the notion of M-estimation. An iterative algorithm is introduced for the derivation of the corresponding nonlinear estimate. The global convergence of this algorithm is rigorously studied. The robust regularized criterion provides nonlinear estimates, which do not suffer from artifacts due to the presence of outliers. In addition, the presence of the stabilizing functional enables the efficient suppression of such outliers. For the evaluation of the regularization parameter, several optimality measures are considered. Moreover, an adaptive structure for this parameter, which leads to high-quality estimates without significantly affecting the computational complexity or the global convergence of the algorithm, is introduced. To further account for the effective preservation of the detailed structure, the concept of M-estimators is embedded in both composite functionals involved in the regularized criterion. It is demonstrated that the corresponding error-penalizing strategy allows the reconstruction of sharp edges, while preserving the robust characteristics of the restoration algorithm. The capabilities of the robust regularized algorithms are demonstrated through restoration examples.
The QOS Broker [distributed multimedia computing]

In human affairs, brokers are intermediaries with specialized knowledge who work toward a mutually desirable outcome through negotiation. The QOS Broker is a software engineering technique that uses this principle to arrange for the delivery of end-to-end quality of service in distributed multimedia systems. An experimental prototype using a telerobotics application helped identify the technique's limitations and system requirements. >
A Mexican Perspective on Learning Disabilities

Given the worldwide trend toward the integration of children with special needs into the general school system, and the Program for Educational Modernization (1989-1994) in Mexico, Mexican educators have had to reassess the politics of special education, focusing on different service delivery models. One model, Integrated Groups, which has been functioning since the 1970s and is primarily for children with learning and language disabilities, is described. New legislation recently enacted recognizes and encourages the collaboration of general education and special education to meet the needs of all children. During the school year 1994-1995, the Secretariat of Public Education (SEP; the Mexican centralized public school system) is piloting, in Mexico City, a proposal for the integration of children into the general classroom. This new model of service delivery is designed to provide greater site-based approaches to the education of individuals with learning disabilities.
Measurement of microchannel fluidic resistance with a standard voltage meter

Abstract A simplified method for measuring the fluidic resistance (Rfluidic) of microfluidic channels is presented, in which the electrical resistance (Relec) of a channel filled with a conductivity standard solution can be measured and directly correlated to Rfluidic using a simple equation. Although a slight correction factor could be applied in this system to improve accuracy, results showed that a standard voltage meter could be used without calibration to determine Rfluidic to within 12% error. Results accurate to within 2% were obtained when a geometric correction factor was applied using these particular channels. When compared to standard flow rate measurements, such as meniscus tracking in outlet tubing, this approach provided a more straightforward alternative and resulted in lower measurement error. The method was validated using 9 different fluidic resistance values (from ∼40 to 600 kPa s mm−3) and over 30 separately fabricated microfluidic devices. Furthermore, since the method is analogous to resistance measurements with a voltage meter in electrical circuits, dynamic Rfluidic measurements were possible in more complex microfluidic designs. Microchannel Relec was shown to dynamically mimic pressure waveforms applied to a membrane in a variable microfluidic resistor. The variable resistor was then used to dynamically control aqueous-in-oil droplet sizes and spacing, providing a unique and convenient control system for droplet-generating devices. This conductivity-based method for fluidic resistance measurement is thus a useful tool for static or real-time characterization of microfluidic systems.
Association between the geographic distribution during the last glacial maximum of Asian wild rice, Oryza rufipogon (Poaceae), and its current genetic variation

Premise of the study The combination of traditional population genetic studies and species distribution modeling (SDM) provides many new insights in detecting phylogeographic signals. In Asian wild rice (Oryza rufipogon), the progenitor of cultivated Asian rice, geographical subdivision has been documented in many genetic studies although the root cause of this subdivision remains unknown. Surprisingly, environmental factors associated with the spatial and temporal distribution of O. rufipogon have rarely been examined. The aim of this study is to understand the historical distribution of O. rufipogon and its relationship to the current geographical pattern of genetic variation. Methods We used SDM to examine the present, past, and future distribution of O. rufipogon. The estimated distribution during the Last Glacial Maximum was then compared with genetic data from our previous work. Key results The predicted paleodistribution of O. rufipogon at the Last Glacial Maximum was separated into disconnected east and west ranges. This past distribution is consistent with the current geographic pattern of genetic variation, with two genetic groups that intergrade. Annual precipitation is the single factor that contributes most to SDM estimates. SDM predictions for 2080 indicate a general trend of increasing probability of presence and range expansion. Conclusions (1) The historically disjunct distribution potentially contributes to the current genetic subdivision of O. rufipogon. (2) Water availability is an important factor that limits the distribution of O. rufipogon. (3) Global warming is a lesser threat than other human-mediated factors to the conservation of this endangered species.
Bodies against the law: Abu Ghraib and the war on terror

In this essay, I argue that the contemporary notion of law has been reduced to regulations and disciplinary codes that do not and cannot give meaning to our emotional lives and moral sensibilities. As a result, we have increasing numbers of what I call “abysmal individuals” who suffer from a split between law—broadly conceived as that which gives form and structure to social life—and personal embodied sensations of pain and pleasure. My attempt to understand the place of Abu Ghraib within American culture leads to an analysis of our valorization of innocence and ignorance that not only becomes the grounds on which we morally (if not legally) excuse abusive behavior as “fun,” but also becomes part of the justification for condoning some forms of violence while condemning others. In addition, I argue that the distinction between legitimate and illegitimate violence trades on underlying assumptions about the relationship between culture and nature, technology and bodies, wherein bodies are imagined as natural and outside of the realm of law.
Per-antenna power constrained MIMO transceivers optimized for BER

This paper considers the linear transceiver optimization problem for multi-carrier multiple-input multiple-output (MIMO) channels with per-antenna power constraints. Because in practical implementations each antenna is limited individually by its equipped power amplifier, this paper adopts the more realistic per-antenna power constraints, in contrast to the conventional sum-power constraint on the transmitter antennas. Assuming perfect channel knowledge both at the transmitter and the receiver, the optimization problem can be transformed into a semi-definite program (SDP), which can be solved by convex optimization tools. Furthermore, several objective functions of the MIMO system, including average bit error rate, can also be optimized by the introduction of the majorization theory.
Mitral Regurgitation due to Intermittent Prosthetic Valvular Dysfunction

A second case of malfunction of a Harken disk valve due to undue disk wear is reported. Two and one-half years after aortic and mitral valvular replacement, the patient had paraprosthetic aortic insufficiency and physical findings suggesting intermittent dysfunction of his prosthetic mitral valve. Catheterization showed intermittent hemodynamic abnormalities; fluoroscopic and cineangiographic findings indicated intermittent mitral regurgitation secondary to undue mitral disk wear. At operation, the excised valve showed normal struts and sewing ring but severe disk wear. There was loss of disk substance and rim notching.
Routes to self-assembly of nanorods

Self-assembled nanostructures often exhibit unique properties that are distinct from those of bulk materials. During the past decade, significant progress has been made in the assembly of nanorods and understanding some of the self-directing assembly mechanisms, particularly related to gold nanorods. Nonetheless, methods that can be scaled up to large areas for device-scale applications are yet to be established. This review describes various routes that are being actively pursued to achieve assembly of nanorods. Self-assembly methods that utilize external forces such as electric field or gravitational forces are reviewed. Additionally, self-assembly schemes using chemical and biomolecule linkers are presented. Other important routes, such as template assisted assembly, Langmuir-Blodgett, and nanorod assembly methods carried out in solution phase are also discussed. The latter includes recently reported approaches to produce superstructured particles through self-assembly. Solvent evaporation and drying can also strongly contribute to the assembly of nanostructures. The final section presents self-assembly routes that primarily exploit the drying kinetics of solvents.
Probing molecular motion by NMR

Recently developed solution NMR methods for measuring 2H, 13C, and 15N spin relaxation, coupled with biosynthetic isotopic enrichment, permit the characterization of backbone and sidechain dynamical properties of proteins on picosecond/nanosecond and microsecond/millisecond timescales. Theoretical interpretations of the relaxation data provide insights into the biophysical and functional properties of proteins.
Challenges in the design of embedded real-time DSP SoCs

This paper focuses on the challenges in the design of embedded real-time DSP SoCs. We first present a generic microarchitecture of an SoC based on a programmable DSP CPU. We then discuss customer requirements for a typical SoC and present SoC design as a multidimensional optimization problem. We highlight the need to look at the design objectives in the context of the complete solution and not just the chip. The paper looks at the challenges in both the SoC definition and the design phases. We propose a concurrent engineering approach for SoC definition and a platform based approach for SoC design. The paper uses DM642 programmable digital media processor SoC as an example to illustrate these approaches.
Test results for the APL/JHU folded-tube aluminum condenser

A 1.1-MWt heat exchanger modeling a concept proposed for ocean thermal energy conversion (OTEC) power plants has been tested as a condenser and performance has exceeded predictions. The overall heat transfer coefficient at design conditions was measured near 2900 W/m-K, varied with water flow rate, but was nearly independent of ammonia flow rate. The unit tested comprises three full-diameter (76-mm), full-length (183-m), folded aluminum tubes operated in parallel in a staggered (by vertical offset) configuration. Water flowed downward by gravity over the tube bundle at 0.4-1.2 m/s; two-phase ammonia flowed downward inside the tubes at 0.22-1.00 kg/s per tube. The experimental results are discussed in terms of stratified and annular flow regimes. The stratified model is found to produce better agreement with the measurements in the range of conditions of greatest interest for OTEC applications.
Retinal Phlebitis in the Irvine-Gass Syndrome

We reviewed the pathology records from January 1965 through July 1975 for aphakic eyes. After exclusion of unsuitable cases, ten eyes (nine patients) with cystoid macular edema and 142 eyes without cystoid macular edema were studied. Clinical ophthalmic records were available for five of the ten eyes with the Irvine-Gass syndrome. Histologic sections were examined, revealing a significant correlation between the Irvine-Gass syndrome and retinal phlebitis, which has not been reported previously, as well as cyclitis and vitritis. Anterior segment operative complications tended to be more prevalent in eyes with the Irvine-Gass syndrome than in those without the Irvine-Gass syndrome, although the assocation was not statistically significant (P less than .1). Retinal trypsin digestion showed the phlebitis to be distributed posteriorly within primary and secondary retinal veins, frequently occurring near points of bifurcation. The changes in permeability seen in the Irvine-Gass syndrome may be due to this retinal phlebitis and to a generalized inflammation-induced increase in capillary permeability. The case of the phlebitis is not known.
Fine pitch TSV integration in silicon micropin-fin heat sinks for 3D ICs

Future high performance 3D systems require a systematic co-design of their electrical interconnect network and their heat removal mechanism. This paper presents fine pitch (20µm) and high aspect ratio (18∶1) TSVs integrated in a micropin-fin heat sink capable of removing power density of 100W/cm2 and resulting in junction temperatures below 50 °C.
Retrospective data collection and analytical techniques for patient safety studies

To enhance patient safety, data about actual clinical events must be collected and scrutinized. This paper has two purposes. First, it provides an overview of some of the methods available to collect and analyze retrospective data about medical errors, near misses, and other relevant patient safety events. Second, it introduces a methodological approach that focuses on non-routine events (NRE), defined as all events that deviate from optimal clinical care. In intermittent in-person surveys of anesthesia providers, 75 of 277 (27%) recently completed anesthetic cases contained a non-routine event (98 total NRE). Forty-six of the cases (17%) had patient impact while only 20 (7%) led to patient injury. In contrast, in the same hospitals over a two-year period, we collected event data on 135 cases identified with traditional quality improvement processes (event incidence of 0.7-2.7%). In these quality improvement cases, 120 (89%) had patient impact and 74 (55%) led to patient injury. Preliminary analyses not only illustrate some of the analytical methods applicable to safety data but also provide insight into the potential value of the non-routine event approach for the early detection of risks to patient safety before serious patient harm occurs.
Rod Bundle Heat Transfer: Steady-State Steam Cooling Experiments

Through the joint efforts of the Pennsylvania State University and the United States Nuclear Regulatory Commission, an experimental rod bundle heat transfer (RBHT) facility was designed and built. The rod bundle consists of a 7×7 square pitch array with spacer grids and geometry similar to that found in a modern pressurized water reactor. From this facility, a series of steady-state steam cooling experiments were performed. The bundle inlet Reynolds number was varied from 1 400 to 30 000 over a pressure range from 1.36 to 4 bars (20 to 60 psia). The bundle inlet steam temperature was controlled to be at saturation for the specified pressure and the fluid exit temperature exceeded 550 °C in the highest power tests. One important quantity of interest is the local convective heat transfer coefficient defined in terms of the local bulk mean temperature of the flow, local wall temperature, and heat flux. Steam temperatures were measured at the center of selected subchannels along the length of the bundle by traversing miniaturized thermocouples. Using an analogy between momentum and energy transport, a method was developed for relating the local subchannel centerline temperature measurement to the local bulk mean temperature. Wall temperatures were measured using internal thermocouples strategically placed along the length of each rod and the local wall heat flux was obtained from an inverse conduction program. The local heat transfer coefficient was calculated from the data at each rod thermocouple location. The local heat transfer coefficients calculated for locations where the flow was fully developed were compared against several published correlations. The Weisman and El-Genk correlations were found to agree best with the RBHT steam cooling data, especially over the range of turbulent Reynolds numbers. The effect of spacer grids on the heat transfer enhancement was also determined from instrumentation placed downstream of the spacer grid locations. The local heat transfer was found to be greatest at locations immediately downstream of the grid, and as the flow moved further downstream from the grid it became more developed, thus causing the heat transfer to diminish. The amount of heat transfer enhancement was found to depend not only on the spacer grid design, but also on the local Reynolds number. It was seen that decreasing Reynolds number leads to greater heat transfer enhancement.Copyright © 2006 by ASME