cssi/SciSciGPT-SciSciNet huggingface dataset:
Alterations in Synaptic Transmission and Plasticity in Hippocampus by a Complex PCB Mixture, Aroclor 1254

Abstract Developmental exposure to polychlorinated biphenyls (PCBs) has been associated with a variety of neurological effects including cognitive dysfunction. The present study assessed the effects of acute in vitro exposure to a complex mixture of highly chlorinated PCBs, Aroclor 1254 (A1254), on synaptic transmission in the hippocampus of the rat. Increases in population spike (PS) amplitude were observed in field potentials recorded from the pyramidal cell layer of CA1 in response to 1.0–3 μg/ml of A1254. PS amplitude was increased by approximately 20% 5–10 min following the beginning of exposure to 3 μg/ml A1254, with some recovery towards baseline amplitudes occurring by 30 min, despite continuous perfusion. Longer exposures revealed that a maintained 10% increase in PS amplitude persisted beyond 90 min of exposure to 3 μg/ml A1254. A second recording electrode in the stratum radiatum revealed modest increases in EPSP slope (∼10%) that were transient. EPSP slope changes appeared within 5 min of exposure to A1254 (3 μg/ml), peaked at 10 min, and declined to baseline levels by 30 min, despite continued perfusion with A1254. Monitoring over a protracted period revealed relatively stable EPSP slope amplitudes following the return to baseline levels. Long-term potentiation (LTP) is a model of synaptic plasticity believed to encompass the physiological substrates of memory. Neither magnitude or persistence of PS potentiation recorded from the stratum pyramidale was affected by 3 μg/ml A1254. LTP of the EPSP slope recorded in the stratum radiatum was also induced to a comparable degree in control and A1254-treated slices. However, the augmentation in the dendritic response was not maintained in the treated slices over the 60-min posttrain recording period. Acute effects of PCBs on calcium homeostasis, protein kinase C translocation, dopaminergic function, and hormonal action may contribute to the pattern of effects seen in synaptic transmission and plasticity in the hippocampus.
The need for leadership in hospital respiratory services.

The duration of a position as physician-director of respiratory services proved to be less than five years in 68 per cent of cases followed. Based on available information, in the 50 such cases, the act of separation was not elective in these instances, except as a final response to an otherwise intolerable situation. Further study revealed the prime cause to be ignorance of the basic essentials of management Technical incompetence was never an issue in cases of separation. The general application of principles of management to the control of respiratory services is illustrated by a series of case reports and subsequent discussion. Presently, candidates aspiring to such positions appear to rely almost entirely on their elaborate technical skills. Choice of such a career option, however, should carry with it an obligation to "learn the rules of the game." Logically, graduate training programs should provide this training.
RECENT DEVELOPMENTS IN SOVIET RADIO AND TELEVISION NEWS REPORTING

Although political orientation remains the main aim of mass media reporting in the Soviet Union, radio and television are now the most important media of news transmission. The ascendency of broadcasting, however, is only one of many developments gradually undermining Soviet control of domestic public opinion, as Mrs. Hollander points out. Her discussion of these developments gives added support to the succeeding article by David Powell on Soviet propaganda effectiveness. Mrs. Gayle Durham Hollander has been on the research staff of the Massachusetts Institute of Technology Center for International Studies since 1963, specializing in Soviet communications.
The contractile ring. II. Determining its brief existence, volumetric changes, and vital role in cleaving Arbacia eggs.

The first cleavage furrow in eggs of Arbacia (sea urchin) is accompanied by a uniform ring of aligned microfilaments, called the contractile ring. Individual contractile ring filaments measure 35–60 A and occasionally appear "hollow." The contractile ring exists from about 20 sec after anaphase to the end of furrowing activity, i.e., 6–7 min at 20°C. It is closely associated with the plasma membrane at all times, and is probably assembled there. It is about 8 µ wide and 0.2 µ thick throughout cleavage. Its volume decreases, however, suggesting a contraction-related disassembly of contractile ring filaments, rather than a sliding-filament mechanism in the strict sense. Cytochalasin B (>10-6 M) arrests cleavage within 60 sec, by which time contractile ring filaments are no longer visible ultrastructurally. The furrow may be seen to recede within this time. Karyokinesis is unaffected. Simultaneous disruption of furrowing activity and of the contractile ring largely confirms the vital role of the contractile ring as the organelle of cell cleavage.
Continuous wavelet based linear time-varying system identification

A systematic framework is developed to address the parametric linear time-varying system identification problem, using the continuous wavelet transform (CWT). The system is modeled by a differential equation with unknown parameters and identified via the time-frequency representation, the ratio of the CWTs of the output and the input. The efficient execution of this system identification algorithm requires selecting appropriate scales from the wavelet transform. Scale selection can be formulated as an optimization problem: find a set of scales that contains the most information about the system's dynamics and has high signal to noise ratio. In addition, selecting scales that have a minimum amount of redundant information is desirable. Three candidate selection metrics are presented that address these criteria and are based on an analytic investigation of the wavelet transform's probabilistic structure. Finally, a non-linear least squares algorithm, coupled with a scale selection algorithm, is presented to identify the system model. Simulations and experiments verify this algorithm's capability of tracking different types of model variation.
Exploring for 3D photonic bandgap structures in the 11 f.c.c. space groups

The promise of photonic crystals and their potential applications1,2 has attracted considerable attention towards the establishment of periodic dielectric structures that in addition to possessing robust complete bandgaps, can be easily fabricated with current techniques. A number of theoretical structures have been proposed3,4,5,6,7,8,9,10,11,12,13,14,15. To date, the best complete photonic bandgap structure is that of diamond networks having Fd3m symmetry (2-3 gap). The only other known complete bandgap in a face-centred-cubic (f.c.c.) lattice structure is that of air spheres in a dielectric matrix (8-9 gap; the so called 'inverse-opal' structure). Importantly, there is no systematic approach to discovering champion photonic crystal structures. Here we propose a level-set approach based on crystallography to systematically examine for photonic bandgap structures and illustrate this approach by applying it to the 11 f.c.c. groups. This approach gives us an insight into the effects of symmetry and connectivity. We classify the F-space groups into four fundamental geometries on the basis of the connectivity of high-symmetry Wyckoff sites. Three of the fundamental geometries studied display complete bandgaps—including two: the F-RD structure with Fm3m symmetry and a group 216 structure with F43m symmetry that have not been reported previously. By using this systematic approach we were able to open gaps between the 2-3, 5-6 and 8-9 bands in the f.c.c. systems.
Extracting multidimensional signal features for content-based visual query

Future large visual information systems (such as image databases and video servers) require effective and efficient methods for indexing, accessing, and manipulating images based on visual content. This paper focuses on automatic extraction of low-level visual features such as texture, color, and shape. Continuing our prior work in compressed video manipulation, we also propose to explore the possibility of deriving visual features directly from the compressed domain, such as the DCT and wavelet transform domain. By stressing at the low-level features, we hope to achieve generic techniques applicable to general applications. By exploring the compressed-domain content extractability, we hope to reduce the computational complexity. We also propose a quad-tree based data structure to bind various signal features. Integrated feature maps are proposed to improve the overall effectiveness of the feature-based image query system. Current technical progress and system prototypes are also described. Part of the prototype work has been integrated into the Multimedia/VOD testbed in the Advanced Image Lab of Columbia University.
‘Intellectual Murder’: Walter Rodney's Groundings in the Jamaican Context

Abstract Walter Rodney's The Groundings with my Brothers (1969), is assessed primarily in the context of 1960s Jamaica. Rodney's efforts to link Marxism and pan-Africanism into a single revolutionary movement and the reasons for his being declared persona non grata by the Jamaican government of the day are examined and evaluated within that context. Rodney's work is seen as continuing to be of relevance in spite of changes in political contexts, both in Jamaica and in the outside world since the 1960s. Rodney's continuing influence on the Caribbean left is considered.
Analyzing local exciton generation profiles as a means to extract transport lengths in organic solar cells

In this work, we determine the carrier-transport lengths of electrons and holes $({L}_{e,h})$ for bulk heterojunction (BHJ) organic solar cells using a method applicable to functional devices. By linking the local exciton generation profile $[G(x)]$ in the photoactive layer to photocurrent losses, we are able to determine the onset of bimolecular recombination, which is the dominate loss process of free carrier transport. Even though many factors affect photocurrent generation, we single out bimolecular recombination by measuring the scaling of photocurrent with light intensity as a function of applied voltage. For the common BHJ system, annealed poly-3-hexylthiophene:[6,6]-phenyl-C61-butyric acid methyl ester (P3HT:PCBM), a minimum for ${L}_{e}$ in PCBM is found to be 340 nm while ${L}_{h}$ is estimated to be 90 nm for P3HT. The relationship between $G(x)$ and carrier transport is further exemplified by demonstrating a scaling exponent below that for traditional space-charge-limited photocurrent. Likewise, by incorporating a drift/diffusion model, an intuitive link between $G(x)$ and charge transport is established where recombination is shown to occur in regions of the photoactive layer far from the electrode of the slowest carrier species. Finally, the consequences of ${L}_{e,h}$ on device design for operation under 1 Sun conditions are described.
The role of neuroimaging in dementia

Potential new therapies for the treatment of Alzheimer's disease demand early and accurate diagnosis. Although clinical evaluation is generally sufficient when the disease is well established, neuroimaging tools are helpful to detect the earliest changes of Alzheimer's disease or differentiate Alzheimer's disease from the other forms of dementia. This article reviews the basic concepts of brain imaging and clinical application. It concludes with a brief discussion of future directions in neuroimaging for the diagnosis and longitudinal follow-up of Alzheimer's disease.
Predictors of referral to the North Carolina Child Service Coordination Program among infants with orofacial clefts.

Abstract Objective: North Carolina has several programs that identify high-risk women and children for needed services, including the Child Service Coordination Program (CSCP). This study determines CSCP referral rates among infants with orofacial clefts (OFCs) and predictors of CSCP referral. We hypothesized receiving Medicaid and maternity care coordination (MCC) services increases the likelihood of CSCP referral. Design and Setting: For births between 1999 and 2002, data were matched from North Carolina Vital Statistics, Health Services Information System (MCC and CSCP data), and North Carolina Birth Defects Monitoring Program. Multivariate analysis was used to determine crude and adjusted odds ratios for sociodemographic variables to predict CSCP referral. Participants: A total of 644 mothers of live-born infants with OFCs in North Carolina were identified. Results: About 45% of infants with OFCs were referred to the CSCP. Infants of mothers who were at least 30 years of age and mothers who had more t...
Acidichromic Spiropyran-Functionalized Mesoporous Silica: Towards Stimuli-Responsive Metal Ion Separations Media

Abstract An acidichromic silyl spiropyran was synthesized and covalently immobilized on the surface of mesoporous silica (SBA-15) through either post-modification or a co-condensation route. The integration of the spiropyran into the porous silica was probed by thermogravimetric analysis, nitrogen adsorption/desorption studies and UV-Vis optical spectroscopy. While the co-condensation route provides the higher spiropyran loading levels, it also leads to two different states of attachment. Both synthetic procedures favor the formation of the open, merocyanine form of the spiropyran within the framework, but this form can be readily switched from a protonated to a deprotonated state by treatment with buffered aqueous solutions. Preliminary evaluation of the metal ion sorption capabilities of the spiro-functionalized SBA-15 for selected monovalent, divalent, and trivalent metal ions indicates that the spiropyran-modified materials show modestly improved cation exchange characteristics versus the unfunctional...
Adhesion Receptors in Health and Disease

Cell adhesion molecules have been recognized to play a major role in a variety of physiological and pathological phenomena. They determine the specificity of cell-cell binding and the interactions between cells and extracellular matrix proteins Some of them may also function as receptors that trigger intracellular pathways and participate in cellular processes like migration, proliferation, differentiation, and cell death. The receptors that mediate adhesion between epithelial cells that are discussed in this review include integrins, selectins, the immunoglobulin superfamily members, and cadherins. The intent of this review is to inform the reader about recent advances in cellular and molecular functions of certain receptors specifically those that are considered important in cell adhesion. We have deliberately not provided all-inclusive detailed information on every molecule, but instead, have presented a generalized overview in order to give the reader a global perspective. This information will be use...
PCSS Lifetime Testing for Pulsed Power Applications

Trigger systems are becoming increasingly important in pulsed power systems with large numbers of switches or large numbers of different switching times. Performance can be critical with demands for fast rise-times, sub-nanosecond jitter, and long lifetimes . In particular, component lifetimes affect maintenance costs and the available operational time of the system. High gain photoconductive semiconductor switches (PCSSs) deliver many of the desired properties including optical-isolation, 350 ps risetime, 100 ps r-m-s jitter, scalability to high power (220 kV and 6 kA demonstrated), and device lifetimes up to 10b shots with 20 A 5 ns wide pulses. However, higher current and longer pulse applications can drastically reduce device lifetime. For typical single shot pulsed power applications, lifetimes of several thousand shots are required and much longer-lived switches are required for repetitive pulsed power applications. The key parameters that impact PCSS lifetime are voltage, current, and pulse width. Voltage affects the lifetime of a lateral switch when the electric field near the surface of the switch approaches the surface breakdown limit, which is approximately 100 kV/cm for pulse charged switches under transformer oil or Fluorinert (a liquid dielectric). The current in high-gain GaAs PCSS always forms filaments, so this lifetime dependence can be considered in terms of the current per filament, and most of our lifetime testing is done with switches producing a single main filament. Since PCSS can have sub-nanosecond risetime and jitter, most of our interest in lifetime is for switches that produce 1-100 ns long pulses. These requirements lead us to testing high gain PCSS in high speed, 50 ohm transmission line, discharge circuits that can deliver up to 300 A. Control of the PCSS is achieved with a fiber-coupled laser directed between the PCSS metal contact pads resulting in randomly formed filaments (one primary). Devices demonstrating long lifetimes are operated at up to a few kilohertz, whereas higher current and longer pulse tests are operated at lower repetition rates. In all cases, rep-rates are below the limit where bubbles form in the liquid dielectric. New switches are always tested at 20 A for direct comparison to the lifetime data that we have accumulated over the last 20 years. Fligher current tests are performed to predict switch lifetimes for specific applications that don't require such long device lifetimes. This paper will discuss testing procedures, circuits, and dramatic changes in PCSS component lifetime due to contact methods (e.g. soldering versus ribbon bonding).
Fitting semiparametric random effects models to large data sets.

SUMMARY For large data sets, it can be difficult or impossible to fit models with random effects using standard algorithms due to memory limitations or high computational burdens. In addition, it would be advantageous to use the abundant information to relax assumptions, such as normality of random effects. Motivated by data from an epidemiologic study of childhood growth, we propose a 2-stage method for fitting semiparametric random effects models to longitudinal data with many subjects. In the first stage, we use
Sirolimus monotherapy following Campath-1H induction☆

Sirolimus was used as a single agent for maintenance immunosuppression in a pilot trial of 29 primary kidney transplant patients using lymphocyte depletion with Campath-1H as an induction strategy. This allowed sirolimus to be analyzed (dose, blood level, and side effect profile) in the absence of steroid and calcineurin inhibitors. A sirolimus dose of 4 mg/day resulted in blood levels in the 8 to 9 ng/mL range. Of the 29 patients, 8 patients (28%) had rejection. The sirolimus levels were not significantly different in patients with or without rejection. The cardiovascular risk profile in terms of lipid profile and hypertension control was favorable. Increase in cholesterol and triglyceride levels at one month (not statistically significant) necessitated treatment in 60% of patients with decline in levels by 6 and 12 months. Management of hypertension was also favorable with the majority of patients (55%) being on one hypertensive medication. Sirolimus monotherapy was well tolerated on the whole. Wound healing, leukopenia, and anemia were not significant problems. In conclusion, monotherapy has been well tolerated with a favorable side effect profile. However, a rejection rate of 28% was noted.
Energetics of shortening muscles in twitches and tetanic contractions. II. Force-determined shortening heat.

The extra heat liberation accompanying muscular shortening, the force-determined shortening heat, is defined as the difference between the heat produced when shortening occurs and that produced in an isometric contraction developing the same amount of force and performing the same amount of internal work. Based on this definition, the initial energy production in twitches and tetanic contractions ( E ) is given by E = A + f ( P, t ) + α F x + W , where A is the activation heat, f ( P, t ), the tension-related heat (a heat production associated with the development and maintenance of tension), α Fx , the force-determined shortening heat, and W , the external work. It is demonstrated that this equation accurately accounts for the time-course of heat evolution and the total initial energy production in both twitches and tetani at 0°C. The force-determined shortening heat is liberated, during shortening, in direct proportion to ( a ) the distance shortened, and ( b ) the force against which shortening occurs. The normalized value of the force-determined shortening heat coefficient, α F/Po , is the same in both the twitch and the tetanus. Finally, this formulation of the muscle's energy production also accounts for the total energy production in afterload isotonic twitches at 20°C, where a Fenn effect is not demonstrable.
The future of chronic obstructive pulmonary disease treatment—difficulties of and barriers to drug development

Although chronic obstructive pulmonary disease (COPD) is a major global health problem with a rising incidence and morbidity, few pharmacotherapeutic advances have been made over the past several decades. The challenges of development of such agents are multifactorial and include rudimentary understanding of the biological genesis of human disease, inadequate in-vitro and in-vivo models, unvalidated biomarkers, inefficient physiological and clinical endpoints, and variable regulatory review worldwide. Blockade of various inflammatory pathways and mediators is a reasonable therapeutic strategy to alter the natural history of COPD. Substantial heterogeneity is evident with respect to clinical presentation, physiology, imaging, response to therapy, decline in lung function, and survival. Numerous endpoints have been proposed for clinical studies in COPD, with new approaches under study. The novel strategy that seems most promising is the use of biomarkers. We hope that with these approaches novel pharmacotherapies will be developed in the near future.
Evaluating the software test strategy for the 2000 Sydney Olympics

The 2000 summer Olympic Games event was a major information technology challenge. With a fixed deadline for completion, its inevitable dependency on software systems and immense scope, the testing and verification effort was critical to its success. One way in which success was assured was the use of innovative techniques using ODC based analysis to evaluate planned and executed test activities. These techniques were used to verify that the plan was comprehensive, yet efficient, and ensured that progress could be accurately measured. This paper describes some of these techniques and provides examples of the benefits derived. We also discuss the applicability, of the techniques to other software projects.
Pyridine- and pyrimidine-functionalized poly(sulfone)s: performance-enhancing crosslinkers for acid/base blend proton exchange membranes used in direct methanol fuel cells

The direct methanol fuel cell (DMFC) is a promising energy conversion device that holds the potential to replace lithium ion batteries used in portable electronic devices. At present, widespread commercialization is impeded in part by the absence of a suitable proton exchange membrane (PEM). To address this need, pyridine- and pyrimidine-functionalized poly(sulfone)s (PPS and PMPS, respectively) were prepared in two high yielding post-polymerization C–H borylation/Suzuki coupling steps from commercially available UDEL® poly(sulfone). Membranes comprised of the aforementioned polymers blended with sulfonated poly(ether ether ketone) (SPEEK) were found to exhibit improved single cell performance and decreased methanol crossover in comparison to plain SPEEK and showed higher power densities than Nafion® 112, an exchange membrane commonly used in DMFCs. Blend properties and single cell performances were found to be dependent on the basicity and steric parameters of the N-heterocycle incorporated into the polymeric material used in the aforementioned membranes.
Cardiopulmonary Bypass During Pregnancy

Background Cardiac surgery during pregnancy carries significant maternal and fetal risk and is typically considered after failure of medical therapy. We sought to determine the maternal and neonatal outcomes of cardiopulmonary bypass during pregnancy. Methods Twenty-one pregnant patients undergoing cardiothoracic surgery were identified from the Mayo Clinic surgical database (1976 to 2009). Maternal and neonatal outcomes were reviewed. Results Operations included 8 aortic valve replacements, 6 mitral valve repair-replacements, 2 myxoma excisions, 1 patent foramen ovale closure, 1 myectomy, 2 aortic aneurysm repairs, and 1 prosthetic aortic valve thrombectomy. Median cardiopulmonary bypass time was 53 minutes (range 16 to 185). Twelve patients (57%) required emergent surgery with a median gestational age (GA) of 25 weeks (range 7 to 35.5). Seven patients underwent cesarean section immediately prior to sternotomy delivering viable infants (median GA 31 weeks). In the remaining patients, three additional preterm births occurred, all in operations performed at an early GA (13 to 15 weeks). Median follow-up was 16 months (range 3 to 305). All patients improved to New York Heart Association functional class I or II. One early maternal death occurred 2 days after emergent mechanical aortic valve thrombectomy and 3 late maternal deaths occurred 2, 10, and 19 years postoperatively. Three fetal deaths occurred in mothers with additional medical comorbidities. Conclusions In the current era, cardiothoracic surgery can be performed with relative safety during pregnancy. Fetal complications (prematurity and death) are associated with urgent, high-risk surgery, maternal comorbidity, and early GA. Emergent surgery appears to confer a higher risk of maternal death.
Prognosis of transient atrioventricular conduction disturbances complicating open heart surgery for congenital heart defects

Abstract Two patients who had open heart correction of ventricular septal defect and atrioventricular canal in 1956 and 1958, respectively, had recurrences of high degree heart block several years after an episode of transient dysrhythmia in the immediate postperfusion period. As a result of these observations, we chose to review our surgical experience during a period when adequate electrocardiographic observations and follow-up studies were available. A total of 911 patients less than 15 years of age had had open heart surgical correction of tetralogy of Fallot, ventricular septal defect or atrioventricular canal from 1960 through 1967. Of the 71 surviving patients who had transient complete heart block, second degree heart block, or atrioventricular dissociation immediately after surgery, 59 could be traced, and only 1 patient (with transient atrioventricular dissociation) had return of the dysrhythmia. During this period, 7 patients had persistent complete heart block after leaving the operating room, and electronic pacing was instituted. Five died within 24 hours after surgery, and the remaining 2 died soon after discharge. The study revealed that the risk of recurrence of transient postoperative high degree heart block or atrioventricular dissociation is low, and the prognosis for patients with sinus rhythm after such an episode is favorable.
An Ocean Bottom Seismograph Using Digital Telemetry and Floating-Point Conversion

An ocean bottom seismograph (OBS) using digital telemetry to convey eight channels of information to a shore station through 10 km of single-conductor armored cable was installed July 27, 1976 at a depth of 600 m off the northeastern coast of Oahu, Hawaii. Power for the OBS is supplied by the shore station through the same cable. A floating-point scheme requires only 12 bits for the digitization of each channel within a 108-dB dynamic range. The eight channels are each sampled at 70/g rate and include: 1) the outputs from three orthogonal 1-Hz geophones; 2) a crystal hydrophone output; 3) a rectified output from the same hydrophone in the 500-1500-Hz band; 4) a temperature and water current sensing thermistor; and 5) two system test channels. The geophones are mounted in self-leveling gimbals with brakes which are released three times each day. A calibration signal is also applied to each geophone calibration coil three times a day. The OBS has recorded on the average two events a day, 70 percent of which are of apparent local origin, and 20 percent of which are apparently earthquakes originating near the island of Hawaii. The digital telemetry scheme enables direct computer connection and digital recording. Using these digital records, ocean noise spectra have been computed and correlated with temperature and current records.
Modeling Tidal Bedding In Distributary-Mouth Bars

Abstract Distributary-mouth bars are important morphological units of deltas which develop under a wide range of wave, tidal, and riverine conditions, and are known to form highly productive subsurface oil and gas reservoirs. This paper extends previous work on purely fluvial mouth bars, to mixed systems where tides are also present. Under these conditions mouth bars can display alternate layers of mud and sand that can ultimately determine their vertical permeability. Herein we propose an analytical, process-based model to explain characteristics of tidal bedding and quantify their extent in mouth bars. Findings from our analytical model are compared with results from the numerical model Delft3D. From landward to seaward and in the absence of tides, our analysis shows that a sand-dominated zone is followed by a depositional environment made of sand and mud mixtures, and finally by mud-dominated areas. With increasing tidal amplitude, the sand–mud mixture zone is gradually replaced by a lamination zone characterized by alternate tidal bedding. Bedding characteristics in mouth bars are defined using the extension of the lamination area and the difference in mud content between coarse and fine sediment layers. Both quantities tend to increase with increasing tidal amplitude. The lamination zone grows while the difference in mud content decreases for small ratios of mud to sand settling velocity and mud to sand concentration. Bottom friction strongly affects tidal bedding by reducing the length of the zone where lamination occurs and increasing differences in mud content between successive layers.
Using Expertise as a Framework for Evaluating Requirements Technology

The field of requirements engineering (RE) is rich with a myriad of technologies that aim to support activities within the requirements engineering process. These range from elicitation to management of RE work products. As such, the range and nature of these technologies are broad; this makes an evaluation of their effectiveness challenging. This position paper proposes an expertise framework as a basis for conducting comparative evaluation of RE technologies. Expertise is characterized using three dimensions: Practical Skill, Theoretical Knowledge, and Problem Domain. Expertise is increased by applying different processes to each dimension: Practical Skill needs to be abstracted; Theoretical Knowledge needs to be conditionalized, and Problem Domains need to be Contextualized. These dimensions and processes can be used as the basis for evaluating requirements tools and methods. In other words, to what extent does a particular technology raise the level of expertise for a requirements engineer by augmenting one of these processes? The framework is presented by applying it to evaluate four different techniques (ethnography, use cases, scenarios, and traceability matrix).
Recent advancements of flow cytometry: new applications in hematology and oncology

Flow cytometry offers great diagnostic opportunities in the vast majority of hematologic and oncologic diseases with multiple cellular and molecular information within an individual cell. We will discuss various applications of flow cytometry, particularly in hematology and oncology, in addition to general principles and limitations of flow cytometry. They include nucleic acid analyses in cancer cells, new methods for assessing rare circulating tumor cells and disease-specific applications in malignancy with emphasis on diagnosis and treatment of hematologic malignancy, including minimal residual disease. With improvement of monoclonal antibodies, fluorescence and laser technology, flow cytometry now offers new avenues of assessing cellular functionality through examination of intracellular compartments. High-throughput quantitative analysis, advancements of in vivo flow cytometry and assessment of minimal residual diseases, as exampled in patient stratification and prediction of leukemia therapeutic response, will further make flow cytometry indispensable in medicine.
Automatic volume management for programmable microfluidics

Microfluidics has enabled lab-on-a-chip technology to miniaturize and integrate biological and chemical analyses to a single chip comprising channels, valves, mixers, heaters, separators, and sensors. Recent papers have proposed programmable labs-on-a-chip as an alternative to traditional application-specific chips to reduce design effort, time, and cost. While these previous papers provide the basic support for programmability, this paper identifies and addresses a practical issue, namely, fluid volume management. Volume management addresses the problem that the use of a fluid depletes it and unless the given volume of a fluid is distributed carefully among all its uses, execution may run out of the fluid before all its uses are complete. Additionally, fluid volumes should not overflow (i.e., exceed hardware capacity) or underflow (i.e., fall below hardware resolution). We show that the problem can be formulated as a linear programming problem (LP). Because LP's complexity and slow execution times in practice may be a concern, we propose another approach, called DAGSolve, which over-constrains the problem to achieve linear complexity while maintaining good solution quality. We also propose two optimizations, called cascading and static replication, to handle cases involving extreme mix ratios and numerous fluid uses which may defeat both LP and DAGSolve. Using some real-world assays, we show that our techniques produce good solutions while being faster than LP.
Optimizing verbal agreement in Mordvin

. In the Mordvin definite conjugation, portmanteau verbal affixes cross-reference the person and number of both subject and object. This complex agreement system shows extensive syncretism, which is more acute among the most marked members of the paradigm. I argue that Optimality-Theory gives a more explanatory account of the pattern of neutralizations in the Mordvin verb than rule-based theories. Predictions of the analysis are tested against data from other Finno-Ugric and Uralic languages.
Screening for Hospitalization and Nutritional Risk Among Community-Dwelling Older Persons

Background: The potential for the use of nutritional screening to identify older persons at risk of hospitalization has not been contrasted with the use of tools developed for predicting hospital admissions. Objective: Our goal was to compare the associations of items from the Level II Nutrition Screen (LII) and the Probability of Repeated Admissions (Pra) questionnaire with the outcome of hospitalization. Design: This was a cohort study of participants in a Medicare managed-risk health plan who completed both the LII and Pra (n = 386). All hospitalizations within 1 y of screening were recorded. Hierarchical multivariate logistic regression was used to model associations with hospitalization. Results: Pra items that retained significant associations with hospitalization were self-reported health, hospitalization in the past year, and >6 doctor visits in the past year (positive predictive value: 20%; sensitivity: 53.1; specificity: 69.7). LII items that retained significant associations with hospitalizatio...
Intense localized rock uplift and erosion in the St Elias orogen of Alaska

The St Elias orogen in Alaska is one of the world’s highest coastal mountain ranges. An age analysis of detrital material in active sediment systems in the inaccessible ice-covered valley bottoms reveals localized exhumation that is driven by coupling between erosion and active tectonic rock uplift.
Mechanism of thermal depolymerization of trimethylsiloxy‐terminated polydimethylsiloxane

“Catalyst-free” trimethylsilyl end-blocked polydimethylsiloxanes of Mn = 68,300 and 111,000 were isothermally depolymerized above 400°C. The volatilized products were a mixture of cyclic oligomers and trace quantities of Me3Si(OSiMe2)nOSiMe3 (n = 0,1). The relative degree of polymerization was followed as a function of fractional conversion. The data were consistent with the oretical curves for a mechanism involving initiation by random siloxane bond cleavage followed by a rapid and complete unzipping of the kinetically active fragments. It is suggested that catalysis may be responsible for the initiation process, thus accounting for the low activation energy (43 Kcal/mol) relative to the siloxane bond energy (108 kcal/mol).
Infinite Hidden Markov Models for Unusual-Event Detection in Video

We address the problem of unusual-event detection in a video sequence. Invariant subspace analysis (ISA) is used to extract features from the video, and the time-evolving properties of these features are modeled via an infinite hidden Markov model (iHMM), which is trained using ldquonormalrdquo/ldquotypicalrdquo video. The iHMM retains a full posterior density function on all model parameters, including the number of underlying HMM states. Anomalies (unusual events) are detected subsequently if a low likelihood is observed when associated sequential features are submitted to the trained iHMM. A hierarchical Dirichlet process framework is employed in the formulation of the iHMM. The evaluation of posterior distributions for the iHMM is achieved in two ways: via Markov chain Monte Carlo and using a variational Bayes formulation. Comparisons are made to modeling based on conventional maximum-likelihood-based HMMs, as well as to Dirichlet-process-based Gaussian-mixture models.
Asymmetries in the Conditional Mean Dynamics of Real GNP: Robust Evidence

We investigate asymmetries in the conditional mean dynamics of U.S. GNP. Because the statistical evidence on nonlinearities in the conditional mean could be influenced by the presence of outliers or by a failure to model conditional heter oske dasticity, we explicitly account for outliers by assuming that the innovations are drawn from the stable family, and model time-varying volatility by a GARCH(1, 1) process. We also allow for the possibility of long memory in the series with fractional differencing. Our results indicate statistically significant nonlinearities in the conditional mean that persist even after accounting for these features in the data.
Use of bevacizumab in recurrent glioblastoma

Glioblastoma (GBM) is the most common adult primary brain neoplasm. Despite advances in treatment, GBM continues to be associated with considerable morbidity and mortality as compared with other malignancies. Standard treatment for GBM results in survival of 12.9 months (95% CI: 12.3-13.7 months) with a median progression-free survival of 7.2 months (95% CI: 6.4-8.2 months) in a modern GBM cohort. These aggressive tumors recur and treatment for recurrent GBM continues to have very poor outcomes. Prior to the use of bevacizumab, monoclonal antibody to VEGF, 6-month progression-free survival in clinical trials for recurrent GBM ranged from 9 to 15%. Trials utilizing bevacizumab and its subsequent US FDA approval have given more hope to recurrent GBM and this concise review discusses bevacizumab in recurrent GBM. This review focuses on time-to-event outcomes (overall survival, progression-free survival and 6-month progression-free survival) in clinical trials utilizing bevacizumab for the treatment of recurrent GBM. For this review, we have chosen to focus primarily on Phase II clinical trials that have been published and available in the literature (PubMed). While we focused primarily on time-to-event variables, toxicity and safety of bevacizumab is very important and this agent can be associated with serious life-threatening toxicities. We have included a general section of toxicities but for a more lengthy review please see the excellent study by Odia and colleagues.
CONGRUENCE OF BOLITOGLOSSINE BIOGEOGRAPHY AND PHYLOGENY WITH GEOLOGIC HISTORY: PALEOTRANSPORT ON DISPLACED SUSPECT TERRANES?

— A vicariance hypothesis of New World biogeography involving transport of living biota on fragments of an ancestral landmass to present positions ranging from southern Alaska to northern South America is developed. Geological, as well as biogeographical, ecological, and systematic data from plethodontid salamanders provide correlative support for the model. Other groups appear to have similar biogeographic histories and, along with further geological data, could provide means of corroboration of this hypothesis. Active biotic dispersal between the American continents before Pliocene closure of the Panamanian isthmus may have been less prevalent than previously believed, and tectonic transport may have dispersed many organisms. If corroborated, geologists may be provided a new method of analyzing relationships among “suspect terranes” using phylogenetic analyses of living biota, and biologists may be required to reassess previous concepts of New World historical biogeography.
Relative Performance Of Very High Speed Integrated Circuit (VHSIC) Chip Sets For Selected Signal Processing Functions

The Very High Speed Integrated Circuit (VHSIC) program was started in 1978 to produce high performance signal processing chips for military systems. Contracts have been let for Phase I for six chip sets. Modules using these chips are also being developed under this phase. Six of the funded modules and two hypothetical modules are examined for nine signal processing tasks.
Transient Performance of Integrated SOFC System Including Spatial Temperature Control

Spatial temperature feedback control has been developed for a simulated integrated non-pressurized simple cycle solid oxide fuel cell (SOFC) system. The fuel cell spatial temperature feedback controller is based on (1) feed-forward set-points that minimize temperature variation in the fuel cell electrode-electrolyte solid temperature profile for the system operating power range, and (2) decentralized proportional-integral based feedback to maintain the fuel cell spatial temperature profile during transients and disturbances. Simulation results indicate the fuel cell spatial temperature variation can be maintained within 15 degrees of nominal to significant load perturbations. Temperature gradients through the fuel cell are needed to remove the heat generated within the cell and cannot be avoided. The goal of the developed spatial temperature control is to minimize temperature variations from a nominal temperature profile in time. Minimal temperature variations in the SOFC electrode-electrolyte solid assembly will result in decreased thermal stresses and thereby decreased degradation and probability-of-failure. Simulation results demonstrating the ability to maintain the SOFC spatial temperature during large load perturbations indicates SOFC could be designed and controlled for rapid load following capability. Such performance can greatly improve SOFC system operating flexibility and thereby open new markets for SOFC systems including load following or spinning reserve services for the utility grid.Copyright © 2010 by ASME
O(-) + acetaldehyde reaction products: search for singlet formylmethylene, a Wolff rearrangement intermediate.

The mass-resolved anionic products of the reaction of O•− with acetaldehyde, H3CCHO, are studied using photoelectron imaging. The primary anionic products are vinoxide, H2CCHO−, formylmethylene anion, HCCHO•−, and ketenylidene anion, CCO•−. From photoelectron spectra of HCCHO•−, the electron affinity of triplet (ground state) formylmethylene (1.87 ± 0.02 eV) and the vertical detachment energy corresponding to the first excited triplet state (3.05 eV) are determined, but no unambiguous assignment for singlet HCCHO could be made. The elusive singlet is a key intermediate in the Wolff rearrangement, resulting in formation of ketene. The fast rearrangement associated with a large geometry change upon photodetachment to the singlet surface may be responsible for the low intensity of the singlet compared to the triplet bands in the photoelectron spectrum. The title reaction also yields CCO•−, whose formation from acetaldehyde is novel and intriguing, since it requires a multistep net-H4+ abstraction. A possible...
Unilateral microscopic gonadoblastoma in a prepubertal Turner mosaic with Y chromosome material identified by restriction fragment analysis.

A high incidence of gonadal tumors has been demonstrated in patients with gonadal dysgenesis in the presence of Y chromosome material. A unilateral, microscopic gonadoblastoma was found in the dysgenetic gonad of a ten-year-old, phenotypic female, with Turner stigmata and chromosome mosaicisms of three cell populations 45,X/46,X,+mar,/47,X,+mar,+mar. It is often impossible to determine by cytogenetic analysis if the marker chromosome has derived from the X or Y chromosome. The origin of these marker chromosomes was elucidated by the use of DNA probe (pDP34) for male-specific sequences of the Y chromosome. The presence of Y-specific fragments in the patient’s DNA led to surgical exploration and the detection of a gonadoblastoma.
The Use of Paraphrase Identification in the Retrieval of Appropriate Responses for Script Based Conversational Agents

This paper presents an approach to creating intelligent conversational agents that are capable of returning appropriate responses to natural language input. Our approach consists of using a supervised learning algorithm in combination with different NLP algorithms in training the system to identify paraphrases of the user’s question stored in a database. When tested on a data set consisting of questions and answers for a current conversational agent project, our approach returned an accuracy score of 79.15%, a precision score of 77.58%and a recall score of 78.01%.
New approaches to management of bleeding disorders.

In many patients, topical hemostatics, antifibrinolytics, and coagulation factor stimulators can eliminate or markedly reduce the need for blood product transfusions—with their attendant hazards and costs. Desmopressin has the added advantage of minimal side effects and a broad range of applications in both hemostatically normal and impaired patients.