cssi/SciSciGPT-SciSciNet huggingface dataset:
Tunable Delivery Of Chemical Gradients Over Large Cell Culture Substrates Using Microfluidic Stacked Flows

Biomolecular gradients play an essential role in studying various biological phenomena such as development, cancer, inflammation, and wound healing. This paper reports a novel microfluidic device for generating tunable biomolecular gradients over large areas on cell culture surfaces. Laminar streams are stacked above the surface to generate a steady-state gradient via diffusion in the direction orthogonal to the flow and to the surface. Finite-element modelling was used to predict negligible shear forces at the range of gradients possible by tuning flow rates. The surface gradients were characterized with fluorescence microscopy; image analysis verified the presence of a one-dimensional gradient across a 2x2 mm area. Fig. 1 shows a variety of surface gradients obtained simply by changing the inlet configuration and pressure settings. Superimposed onto these images are the linescans taken across 4 different regions of the device which demonstrate lateral uniformity (excluding edge effects near walls <25% of area). Due to the binary branching of the inlets, the perfused area can be arbitrarily wide (here, 2 mm). This enables analyzing responses of large cell populations in parallel and acquiring rich statistics on single-cell variability.View Large Image | View Hi-Res Image | Download PowerPoint Slide
Teacher Evaluation: The Limits of Looking

issue of stability and consistency of teaching, research on this topic will be reviewed. These background sec­ tions will be followed by a presen­ tation of empirical data dealing with teachers teaching different subject areas. The background material and the empirical study will then be used to support the argument that direct observation of teachers has serious limitations as an evaluation procedure, particularly because so much depends on the occasion of observation. These limitations must be acknowledged and addressed directly in teacher evaluation settings.
The chemosensory system of the monophagus grasshopper, Bootettix argentatus bruner (Orthoptera : Acrididae)

Abstract Bootettix argentatus (Orthoptera : Acrididae) is a monophagous grasshopper in the subfamily Gomphocerinae. The numbers of chemoreceptors in most groups on the mouthparts increase with each molt and are generally similar in the 2 sexes. There are fewer sensilla in the A3 groups than in other gomphocerine grasshoppers, and the possibility that this is related to host-plant specificity is discussed. Only very small numbers of sensilla are present on the pulvillar pads of the tarsi and on the arolia. The number of sensilla on the antennae is proportional to the length of the flagellum and coeloconic sensilla comprise 30–35%. Most of the remainder are multiporous basiconic sensilla. Adult males have more antennal sensilla than adult females.
Continuation of periodic solutions in the waveguide array mode-locked laser

Abstract We apply the adjoint continuation method to construct highly accurate, periodic solutions that are observed to play a critical role in the multi-pulsing transition of mode-locked laser cavities. The method allows for the construction of solution branches and the identification of their bifurcation structure. Supplementing the adjoint continuation method with a computation of the Floquet multipliers allows for explicit determination of the stability of each branch. This method reveals that, when gain is increased, the multi-pulsing transition starts with a Hopf bifurcation, followed by a period-doubling bifurcation, and a saddle–node bifurcation for limit cycles. Finally, the system exhibits chaotic dynamics and transitions to the double-pulse solutions. Although this method is applied specifically to the waveguide array mode-locking model, the multi-pulsing transition is conjectured to be ubiquitous and these results agree with experimental and computational results from other models.
Handling the Handbag Diagram in Compton Scattering on the Proton

Poincare invariance, gauge invariance, conservation of parity and time reversal invariance are respected in an impulse approximation evaluation of the handbag diagram. Proton wave functions, previously constrained by comparison with measured form factors, that incorporate the influence of quark transverse and orbital angular momentum (and the corresponding violation of proton helicity conservation) are used. Computed cross sections are found to be in reasonably good agreement with early measurements. The helicity correlation between the incident photon and outgoing proton, K{sub LL}, is both large and positive at back angles. For photon laboratory energies of {le} 6 GeV, we find that K{sub LL} {ne} A{sub LL}, D{sub LL} {ne} 1, and that the polarization P can be large.
Hydrogenic orbitals as minimum‐basis functions for SCF calculations

The orbital approximation that polyelectronic atoms can be qualitatively described by using hydrogenlike orbitals was tested quantitatively. Hydrogenic atomic orbitals (HTO's) were investigated as best-atom minimum-basis set functions and were compared to best-atom Slater orbitals (STO's). The two sets of wave functions were compared in terms of the ground-state energies, the electron densities at the nuclei, charge distribution in space, electron populations, and atomic “radii.” In the atomic calculations the HTO's give somewhat poorer atom descriptions that STO's. SCF calculations on diatomic molecules (N2, CO, and HF) indicate that while HTO's give higher molecular energies, they closely mimic STO's in terms of electronic reorganization. The principal difference between HTO and STO results was attributed to the compact nature of the HTO 2s orbital.
Designing Effective Learning Environments for Continuing Education

Advances in technology for distance learning present better-than-ever opportunities for designing learning environments that bring optimal features of the conventional classroom to distributed learners. Yet, with the advantages of reaching learners come corresponding challenges for meeting many and varied cognitive, motivational, and organizational needs. Anchoring design of distance learning instruction solidly in current research from cognitive science and motivation, as well as utilizing tested principles of instructional design theory, provides for optimal balance of strategic decision-making and appropriate management of trade-offs in design of effective learning environments. This paper shows how Bransford, Brown, and Cocking's (1999) four characteristics of effective learning environments can be developed for continuing education, to maximize learning, transfer of learning, and motivation. As illustration, I will focus on the process of translating traditional continuing education (CE) from lecture-based, on-site instruction to Web-based instruction, a trend in many institutions of higher education.
Perioperative incidence and management of hyponatremia in vWD patients undergoing adenotonsillectomy.

Objectives/Hypothesis: To analyze the incidence and severity of hyponatremia in patients receiving synthetic desmopressin (DDAVP) in the perioperative setting of oropharyngeal surgery in the treatment of von Willebrand disease and to propose a standardized protocol for perioperative fluid resuscitation and postoperative sodium monitoring after DDAVP administration. Study Design: Retrospective medical record review. Methods: A retrospective medical record review in an academic pediatric medical center was conducted. From October 1, 2002, to February 1, 2009, all patients undergoing adenotonsillectomy and receiving DDAVP preoperatively for the treatment of von Willebrand disease were identified. A total of 76 patients were identified by initial database review; 63 patients were included in the study, and 13 patients were excluded secondary to incomplete data. DDAVP dose and timing, perioperative fluid volume and composition, and postoperative sodium levels were collected. Extreme adverse events related to hyponatremia were recorded. Results: Forty-seven of 63 (74.6%) patients developed some degree of hyponatremia after DDAVP administration, and six of 63 (9.5%) patients developed extreme hyponatremia, with the degree of hyponatremia related to the volume of perioperative fluid resuscitation. The sodium nadir occurred within 9 to 20 hours after DDAVP administration. No serious adverse events related to hyponatremia were recorded during the study period. Conclusions: The incidence of hyponatremia in children receiving DDAVP for prophylaxis of intraoperative bleeding following oropharyngeal surgery is high. The degree of hyponatremia is related to the perioperative fluid volume administered. A protocol for DDAVP administration, perioperative fluid resuscitation, and postoperative sodium monitoring that aims to reduce the incidence of hyponatremia in this population is proposed.
FURTHER STUDIES OF THE TRANSPORT OF PROTEIN TO NERVE ENDINGS

Mice were injected intracerebrally with [l-14C]leucine, and the specific activities of subcellular fractions of brain and effractions of isolated nerve endings were determined. There was a progressive increase in the specific activity of protein associated with isolated nerve endings after incorporation of [l-14C]leucine into whole brain protein had terminated. Although, the incorporation of [14C]leucine into soluble protein of whole brain did not differ significantly in mice which were 3 months or 1-year old, the subsequent increase in specific activity of soluble protein isolated from nerve endings was significantly greater in the younger animals; 6-month-old mice were intermediate. Therefore, changes in some aspect of the transport of protein to nerve endings is altered even after sexual maturity. Anaesthetization with pentobarbitone during incorporation of [14C]leucine into protein, and inhibition of protein synthesis with acetoxycycloheximide after incorporation of [14C]leucine was complete, did not interfere with the subsequent appearance of radioactive protein at the nerve ending. Evidence is presented for the transport, from a proximal site of synthesis, of protein associated with particulate components of the nerve ending, including synaptic vesicles.
Deciding Full Branching Time Logic

In this paper the full branching time logic (CTL*) is studied. It has basic modalities consisting of a path quantifier, either A (“for all paths”) of E (“for some path”), followed by an arbitrary linear time assertion composed of unrestricted combinations of the usual linear temporal operators F (“sometime”), G (“always”), X (“nexttime”), and U (“until”). It is shown that the problem of determining if a CTL* formula is satisfiable in a structure generated by a binary relation is decidable in triple exponential time. The decision procedure exploits the special structure of the finite state ω-automata for linear temporal formulae which allows them to be determinized with only a single exponential blowup in size. Also the expressive power of tree automata is compared with that of CTL* augmented by quantified auxillary propositions.
Processing and Properties of Nanostructured Magnetic Materials

We report here a novel thin film processing method based upon pulsed laser deposition to process nanocrystalline materials with accurate size and interface control with improved mechanical and magnetic properties. Using this method, single domain nanocrystalline Fe and Ni particles in 5–10 nm size range embedded in amorphous alumina as well as crystalline TiN have been produced. By controlling the size distribution in confined layers, it was possible to tune the magnetic properties from superparamagnetic to ferromagnetic behavior. Magnetic hysteresis characteristics below the blocking temperature are consistent with single-domain behavior. The paper also presents our results from investigations in which scanning transmission electron microscopy with atomic number contrast (STEM-Z) and energy loss spectroscopy (EELS) were used to understand the atomic structure of Ni nanoparticles and interface between the nanoparticles and the surrounding matrices. It was interesting to learn from EELS measurements at interfaces of individual grains that Ni in alumina matrix does not from an ionic bond indicating the absence of metal-oxygen bond at the interface. The absence of metal-oxygen bond, in turn, suggests the absence of any dead layer on Ni nanoparticles even in an oxide matrix.Copyright © 2002 by ASME
Disease-free survival in children with Ewing's sarcoma treated with radiation therapy and adjuvant four-drug sequential chemotherapy

Adjuvant chemotherapy was added to local radiation therapy for patients with Ewing's sarcoma to treat widespread microfoci of disease presumed to be present at the time of diagnosis. Since June 1970, 12 children have been treated with radiation therapy and sequential adjuvant chemotherapy: dactinomycin, adriamycin, vincristine, and cyclophosphamide, continued for 2 years. Two children developed reversible congestive heart failure after cumulative adriamycin doses of 905 mg/m2 in one patient and 720 mg/m2 in another patient who had mediastinal irradiation. Adriamycin is now generally limited to cumulative doses of 720 mg/m2 but is further limited to 500 mg/m2 in children who receive mediastinal or pulmonary irradiation. Of 12 children entered into this study and followed for from 10 to 37 months, all continue in disease-free remission without evidence of recurrent tumor, metastatic tumor, or central nervous system disease.
On velocity scaling in molecular dynamics simulations

The effect of scaling the molecular velocities to a fixed total energy in molecular dynamics simulations within the (N,V,E) ensemble has been investigated. The effect of using different time steps is also discussed. It is found that, even for small time steps, velocity scaling has a substantial influence on the resulting molecular trajectories, velocities, and forces. Furthermore, velocity rescaling and larger time step seem to have an additive effect on the calculated trajectories, but not on the average thermodynamic properties, such as temperature, pressure, and energy.
Experiences in frozen blood preservation using 25,000 and 40,000 molecular weight polyvinylpyrrolidone as a protective agent.

Summary Survival studies were performed in patients on blood which had been frozen in liquid nitrogen with polyvinylpyrrolidone preservatives of 25,000 and 40,000 molecular weights. Little difference was seen in the survivals of the blood frozen with the two molecular weight polymers. The smaller molecular weight material was excreted in the urine more completely. Multiple survival tests in patients using the same unit of frozen-thawed blood revealed a variation from patient to patient at times, while other dual survival studies appeared to parallel one another.
Evaluation of long-term therapeutic efficacy of behavior modification program with chronic male psychiatric inpatients.

Abstract An experimental Behavior Modification Program (BMP) was carried out on fifteen diagnosed chronic schizophrenic male patients on a mixed-population open psychiatric unit in a VA Medical Center. Treatment consisted of positive-reinforcement and response-cost contingency procedures and was conducted for 85, 80, 75 and 70 sessions, respectively, for the fifteen patients. These psychiatric patients were recruited for treatment based on staff documentation and reports of gross verbal abuse, non-attendance at assignments, poor grooming skills, and excessive drinking behavior while circulating on the mixed-population open psychiatric ward. Three to four of the aforementioned inappropriate (target) behaviors were selected for each subject and were treated sequentially in a multiple baseline design. Both procedures were highly successful for the fifteen male psychiatric patients in changing three of their targeted behaviors, but only partially effective for eight of those patients with drinking behavior problems. Follow-up assessment of the participants in the study indicated that most of the positive effects of intervention persisted over 6–12 months post-treatment periods. Of the fifteen inpatients that participated in the BMP, fourteen have been discharged into community foster homes and one remains on the open psychiatric ward awaiting placement outside the hospital.
Gram-positive superinfections: A consequence of modern β-lactam chemotheraphy

Abstract This review of superinfections following β-lactam chemotherapy shows significant variations in the risks of gram-positive and all-organism secondary morbidity. Cefotaxime and structurally similar cephems appear to have the lowest rate of all-organism and incidence of gram-positive enterococcal superinfection. Several possible mechanisms for this favorable finding included synergistic interactions of cefotaxime and desacetylcefotaxime, in vitro activity against most significant pathogens, enhanced antienterococcal activity in the presence of human serum, and significant β-lactamase stability. Variations between cefotaximelike compounds as compared to superinfection rate may be caused by bowel flora alterations and subsequent development of drug-resistant populations. We eagerly await additional review reports on the risks of ceftizoxime, ceftriaxone, and cefmenoxime superinfection.
Effects of couples' characteristics on contraceptive use in sub-Saharan Africa: The Ghanaian example

Using data from the 1988 Ghana Demographic and Health Survey, this study examines couples' demographic and socioeconomic characteristics in the context of their attitudes towards family planning, and the impact of these factors on the use of contraceptives. The characteristics of the husbands and their influence on wives' behaviour illustrate the role of intra-household relations between men and women and their effect on fertility-related behaviour in patriarchal African societies.
Fatigue life estimation of fluttering panels

Fluttering isotropic rectangular flat plate fatigue life estimation, taking into account stress, dynamic pressure, frequency, Mach number and plate thickness
Single-Parent Families: A Difference that Makes a Difference?:

Single-parent families can no longer be viewed as nontraditional families. More than 25% of American families are headed by either a mother or a father. As more single-parent families have appeared...
PREVALENCE OF SELECTED ZOONOTIC DISEASES IN VERTEBRATES FROM HAITI, 1972

Vertebrate animals collected in Haiti in 1972 were tested for selected zoonotic diseases. No rabies virus or neutralizing (N) antibody was detected in bats (Artibeus jamaicensis). However, N antibody against St. Louis encephalitis, Western equine encephalitis (WEE), and Eastern equine encephalitis were detected in resident species of birds and WEE antibody in bats. No N antibody against Venezuelan equine encephalitis was found. The possible introduction by migratory birds and local transmission of these arboviruses is discussed.
Engineering a conformant probabilistic planner

We present a partial-order, conformant, probabilistic planner, Probapop which competed in the blind track of the Probabilistic Planning Competition in IPC-4. We explain how we adapt distance based heuristics for use with probabilistic domains. Probapop also incorporates heuristics based on probability of success. We explain the successes and diefficulties encountered during the design and implementation of Probapop.
Network isolation and local diversity in neutral metacommunities

Biologists seek an understanding of the biological and environmental factors determining local community diversity. Recent advances in metacommunity ecology, and neutral theory in particular, highlight the importance of dispersal processes interacting with the spatial structure of a landscape for generating spatial patterns and maintaining biodiversity. The relative spatial isolation of a community is traditionally thought to have a large influence on local diversity. However, isolation remains an elusive concept to quantify, particularly in metacommunities with complex spatial structure. We represent the metacommunity as a network of local communities, and use network centrality measures to quantify the isolation of a local community. Using spatially explicit neutral theory, we examine how node position predicts variation in alpha diversity across a metacommunity. We find that diversity increases with node centrality in the network, but only when centrality is measured on a given scale in the network that widens with increasing dispersal rates and narrows with increasing evolutionary rates. More generally, complex biodiversity patterns form only when the underlying geography has structure on this critical scale. This provides a framework for understanding the influence of spatial geographic structure on global biodiversity patterns.
On-line computer system to minimize laser injuries during surgery: preliminary system layout and proposal of the key features.

The aim of this paper is to investigate some new user interface ideas and related application packages which aim to improve the degree of safety in an operating room during surgical operations in which an invasive laser beam is deployed. The overall value of the proposition is that a means is provided which ensures the successful completion of the surgical case while minimizing the risk of thermal and mechanical injuries to healthy tissues adjacent to the surgical field. According to surgeons operating with a variety of CO2 lasers available at both the National Cancer Institute in Milan, Italy, and the Sackler School of Medicine, Tel Aviv University, Israel, each laser device presents different cutting and coagulation properties. In order to identify which 'ideal' procedure might corroborate the subjective impression of each surgeon and also to provide one common tool to ensure procedures with a high level of safety, the author has worked for several months with surgeons and technicians of both Institutions to define the general design of a new on-line surgical operation planning and design system to be used during the pre-operative briefing activities and also as a consultation tool during operation. This software package will be developed and tested on both 'C' and FORTRAN compilers running on a commercially available PC which is driving a continuous wave (CW) CO2 laser device via its Instrument Bus interface. The present proposal describes the details of a software package called LCA (Laser-beam Controller and Adviser) which performs several controls in parallel on the key output parameters of a laser beam device during its utilization in delicate surgical operations. The required performances of this device needed during a given surgical operation are pre-simulated and compared against the well-known safety limits, which are stored in the computer's mass storage. If the surgeon's decision about the laser device set-up are considered to be too close to the required physiological safety limits, then the SW alerts the surgeon and proposes alternatives based on other combinations of both HW and SW configurations. An additional application of LCA uses this SW as a warning tool during the operation itself. If a wrong set-up of the laser device is accidentally used, an alarm will be generated and the laser beam automatically switched-off prior to an 'incident report' printout. The operation will continue only when the surgeon validates the choices that the SW suggests for implementation. If necessary, the surgeon can switch off the device and continue to operate it manually. In this case, the surveillance mode will be totally excluded. Language: en
Calcium Binding of Phosphopeptides Derived from Hydrolysis of a αs-Casein or β-Casein Using Immobilized Trypsin

Calcium binding to casein phosphopeptides that were derived from alpha s-CN or beta-CN was studied. Purified alpha s-CN or beta-CN was prepared from fresh skim milk using an anion-exchange column. Peptides were prepared by casein hydrolysis using a fluidized bed bioreactor containing 2 ml of immobilized trypsin (activity: 49.4 U/g of beads). The disappearance of intact protein and the appearance of products of low molecular mass were monitored by SDS-PAGE. alpha s-Casein and beta-CN hydrolysates were loaded on an anion-exchange column, followed by stepwise elution with 0, 0.1, 0.2, 0.4, and 0.5 M KCl in equilibration buffer to separate the phosphopeptides from the other casein peptides. Protein and P were measured in the elution peaks. Calcium binding to each fraction was determined with a Ca-selective electrode. Electrophoresis showed that intact proteins were hydrolyzed rapidly, and peptides appeared on the gel in greater concentrations as the incubation time increased. The major products were a main band with a molecular mass of 6.2 kDa from beta-CN hydrolysates and a series of bands from 4.0 to 12.8 kDa from alpha s-CN hydrolysate. The greatest yield and concentration of phosphate from beta-CN hydrolysate were found in the peak that eluted with 0.4 M KCl in equilibration buffer and for alpha s-CN in the peak that eluted with 0.1 M KCl. The alpha s-CN phosphopeptides showed greater Ca2+ binding than the phosphopeptides from beta-CN. Separation of casein phosphopeptides using anion exchange was not specific. However, results showed that each peak containing high concentrations of phosphate had Ca(2+)-binding ability. Further characterization of these casein phosphopeptides might result in a Ca-complexing food ingredient.
A Comparative Analysis of Online Learning Materials Aimed Toward Integrating Great Lakes Science Into the K-8 Classroom

We surveyed the use of Great Lakes online learning materials by a sample of K-8 teachers. Analyses tested for correlation of use with 1) whether teachers learned about the resources in pre- or in-service education, 2) geographical significance, and 3) whether teachers taught about the topics emphasized in the online learning materials. We compared findings for the Great Lakes to an ocean resource (BRIDGE) and more general Earth System Science online learning materials. Teachers reported using the Internet for teaching and planning. However, very few teachers reported using Great Lakes materials, BRIDGE, and most of the generalized online learning materials. The exception was the National Oceanic and Atmospheric Administration National Weather Service webpage, used by >50% of respondents. Teachers who learned how to use online learning materials in pre-service or in-service education were more likely to use them in-service. There was no significant effect of geographic proximity to the Great Lakes or ocean...
Literacy for Students With Severe Developmental Disabilities What Should We Teach and What Should We Hope to Achieve

The purpose of this article is to propose a conceptual foundation for early literacy instruction for students with severe developmental disabilities. The two primary outcomes in the conceptual model are (a) enhanced quality of life through shared literature and (b) increased independence as a reader. Guidelines are offered for promoting shared literature by increasing opportunities for accessing literature and teaching access skills to students. For increasing students’ independence as readers, recommendations are provided on teaching the components of reading outlined by the National Reading Panel. The proposed model will help develop guidance on the strategies for literacy instruction for students with severe developmental disabilities.
Data-thinning algorithms for “over-sampled” multi-parameter ocean optics data

The deployment of towed depth-profiling paravane systems and autonomous gliders is providing a wealth of high-resolution oceanographic datasets. These datasets are, however, over-sampled in space and time. This paper describes a data-adaptive, user-configurable method that has been used to significantly reduce the time/space density of such data without compromising the inherent scientific information that they provide. The method involves sub-sampling at fixed space and time intervals with additional samples being kept given either a significant change (1) in the depth extent of the alongtrack profiles, or (2) in the values of the profiles themselves. An example is provided showing how well the algorithm works on nearly 5,000 chlorophyll fluorescence profiles collected off the coast of Australia.
Complications associated with primary and secondary perforation of the bladder following immediate instillations of epirubicin after transurethral resection of superficial urothelial tumours

Introduction Significant decreases in tumour recurrence rates of up to 50% are reported after one immediate postoperative instillation of chemotherapeutic drugs, such as epirubicin or mitomycin C. However, the extremely rare occurrence of complications related to perforation of the bladder can be detrimental. Perforation of the bladder seems to be iatrogenic (primary) or drug-induced (secondary). Materials and methods We present two cases of significant morbidity related to primary and secondary perforation of the bladder following two instillations of epirubicin. Results The patient with the primary perforation was managed conservatively, while the second was subjected to immediate surgical exploration. The two patients were finally released in good condition. Conclusions Complications concerning a primary perforation of the bladder and instillation of chemotherapeutic drugs can be easily avoided by recognising the perforation intraoperatively. However, we postulate that a delayed perforation of the bladder might occur due to the cytotoxic effect to the bladder tissue of the instilled drugs.
Human Immunodeficiency Virus Type 1 Vpr-Mediated G2 Arrest Requires Rad17 and Hus1 and Induces Nuclear BRCA1 and γ-H2AX Focus Formation

Eukaryotic cells have evolved a complex mechanism for sensing DNA damage during genome replication. Activation of this pathway prevents entry into mitosis to allow for either DNA repair or, in the event of irreparable damage, commitment to apoptosis. Under conditions of replication stress, the damage signal is initiated by the ataxia-telangiectasia-mutated and Rad3-related kinase ATR. We recently demonstrated that the human immunodeficiency virus type 1 (HIV-1) gene product viral protein R (Vpr) arrests infected cells in the G2 phase via the activation of ATR. In the present study, we show that the activation of ATR by Vpr is analogous to activation by certain genotoxic agents, both mechanistically and in its downstream consequences. Specifically, we show a requirement for Rad17 and Hus1 to induce G2 arrest as well as Vpr-induced phosphorylation of histone 2A variant X (H2AX) and formation of nuclear foci containing H2AX and breast cancer susceptibility protein 1. These results demonstrate that G2 arrest mediated by the HIV-1 gene product Vpr utilizes the cellular signaling pathway whose physiological function is to recognize replication stress. These findings should contribute to a greater understanding of how HIV-1 manipulates the CD4-lymphocyte cell cycle and apoptosis induction in the progressive CD4-lymphocyte depletion characteristic of HIV-1 pathogenesis.
Endovenous ablation of incompetent saphenous veins: a large single-center experience.

Purpose:To evaluate the effectiveness of endovenous treatment of symptomatic varicose veins using the endovenous laser (EVL) or radiofrequency (RF) energy over a >3-year follow-up.Methods:From Febr...
The magnitude of late paleozoic glacioeustatic fluctuations: A synthesis

A comprehensive literature review shows that the magnitude of eustatic fluctuations varied throughout the Carboniferous and Permian and that at least eight distinct phases can be recognized. Facies juxtapositions in carbonate successions and erosional relief in clastic successions indicate that glacioeustatic fluctuations of 20–25 m, and occasionally as much as 60 m, took place throughout the early Mississippian (Tournaisian)—a widely recognized glacial period. Middle Mississippian (mid-Chadian through Holkerian) shallow marine carbonate and clastic successions indicate that eustatic fluctuations were 10–25 m, a decrease that matches well with the paucity of coeval glacial deposits. Late Visean (Asbian through mid-Brigantian) glacioeustatic fluctuations of 10–50 m record the initial phases of ice accumulation in advance of the widespread mid-Carboniferous glacial event. The latest Mississippian–earliest Pennsylvanian (mid-Brigantian through Langsettian) was a time of widespread glaciation, and strata of this age commonly exhibit evidence of glacioeustatic fluctuations of as much as 40–100 m. Although middle Pennsylvanian (Duckmantian through Asturian) glacial deposits are present in eastern Australia, paleovalley depths suggest that coeval glacioeustatic fluctuations were less than 40 m. Glacioeustatic fluctuations of as much as 100–120 m have been widely reported from late Pennsylvanian–earliest Permian (Stephanian through mid-Sakmarian) successions in North America, an increase that corresponds to the growth of large ice sheets across much of Gondwana and the accumulation of ice in the northern hemisphere. Incision and facies juxtaposition in Early–middle Permian (mid-Sakmarian through Kungurian) successions in eastern Australia indicate that glacioeustatic fluctuations of 30–70 m occurred during the waning stages of major glaciation. Erosional relief in paleoequatorial carbonates and the presence of coeval glacial deposits in Australia suggests that eustatic fluctuations of 10–60 m occurred during the final stages of glaciation in the middle to Late Permian (Roadian through Capitanian), but the modest size of most of these fluctuations makes it difficult to isolate the glacioeustatic signature. This review demonstrates that far-field cyclic successions record changing glacial conditions in Gondwana, that the magnitude of glacioeustatic fluctuations was directly related to the volume of glacial ice, that Carboniferous–Permian glacioeustasy was more variable than previously recognized, and that generalizations from short temporal intervals are probably not representative of the late Paleozoic ice age as a whole. Although any attempt to quantify the magnitude of ancient eustatic changes is based on caveats and assumptions, this review incorporates the results of over 100 published papers on the topic in an attempt to minimize the errors inherent in any one study.
NetExplore: a web server for modeling small network motifs

Motivation: Quantitative and qualitative assessment of biological data often produces small essential recurrent networks, containing 3–5 components called network motifs. In this context, model solutions for small network motifs represent very high interest. Results: Software package NetExplore has been created in order to generate, classify and analyze solutions for network motifs including up to six network components. NetExplore allows plotting and visualization of the solution's phase spaces and bifurcation diagrams. Availability and implementation: The current version of NetExplore has been implemented in Perl-CGI and is accessible at the following locations: http://line.bioinfolab.net/nex/NetExplore.htm and http://nex.autosome.ru/nex/NetExplore.htm. Contact: moc.liamg@oknestapap.irtimd Supplementary information: Supplementary data are available at Bioinformatics online.
Regulation of Ca2+-dependent K+ Current by αvβ3 Integrin Engagement in Vascular Endothelium

Abstract Interactions between endothelial cells and extracellular matrix proteins are important determinants of endothelial cell signaling. Endothelial adhesion to fibronectin through αvβ3 integrins or the engagement and aggregation of luminal αvβ3 receptors by vitronectin triggers Ca2+ influx. However, the underlying signaling mechanisms are unknown. The electrophysiological basis of αvβ3 integrin-mediated changes in endothelial cell Ca2+ signaling was studied using whole cell patch clamp and microfluorimetry. The resting membrane potential of bovine pulmonary artery endothelial cells averaged -60 ± 3 mV. In the absence of intracellular Ca2+ buffering, the application of soluble vitronectin (200 μg/ml) resulted in activation of an outwardly rectifying K+ current at holding potentials from -50 to +50 mV. Neither a significant shift in reversal potential (in voltage clamp mode) nor a change in membrane potential (in current clamp mode) occurred in response to vitronectin. Vitronectin-activated current was significantly inhibited by pretreatment with the αvβ3 integrin antibody LM609 by exchanging extracellular K+ with Cs+ or by the application of iberiotoxin, a selective inhibitor of large-conductance, Ca2+-activated K+ channels. With intracellular Ca2+ buffered by EGTA in the recording pipette, vitronectin-activated K+ current was abolished. Fura-2 microfluorimetry revealed that vitronectin induced a significant and sustained increase in intracellular Ca2+ concentration, although vitronectin-induced Ca2+ current could not be detected. This is the first report to show that an endothelial cell ion channel is regulated by integrin activation, and this K+ current likely plays a crucial role in maintaining membrane potential and a Ca2+ driving force during engagement and activation of endothelial cell αvβ3 integrin.
Putatively Noncoding Transcripts Show Extensive Association with Ribosomes

There have been recent surprising reports that whole genes can evolve de novo from noncoding sequences. This would be extraordinary if the noncoding sequences were random with respect to amino acid identity. However, if the noncoding sequences were previously translated at low rates, with the most strongly deleterious cryptic polypeptides purged by selection, then de novo gene origination would be more plausible. Here we analyze Saccharomyces cerevisiae data on noncoding transcripts found in association with ribosomes. We find many such transcripts. Although their average ribosomal densities are lower than those of protein-coding genes, a significant proportion of noncoding transcripts nevertheless have ribosomal densities comparable to those of coding genes. Most show increased ribosomal association in response to starvation, as has been previously reported for other noncoding sequences such as untranslated regions and introns. In rich media, ribosomal association is correlated with start codons but is not usually consistent and contiguous beyond that, suggesting that translation occurs only at low rates. One transcript contains a 28-codon open reading frame, which we name RDT1, which shows evidence of translation, and may be a new protein-coding gene that originated de novo from noncoding sequence. But the bulk of the ribosomal association cannot be attributed to unannotated protein-coding genes. Our primary finding of extensive ribosome association shows that a necessary precondition for selective purging is met, making de novo gene evolution more plausible. Our analysis is also proof of principle of the utility of ribosomal profiling data for the purpose of gene annotation.
Meltblown structures formed by a robotic and meltblowing integrated system: Impact of process parameters on pore size

Our earlier studies have evaluated the effect of meltblowing process parameters on fiber diameter and orientation distribution. This paper deals with parametric studies evaluating the effect of polymer throughput, attenuating air pressure, take-up speed of the web, fiber stream approach angle, and die-to-collector distance (DCD) on pore sizes and their distribution in meltblown nonwoven webs. Pore sizes and their cumulative frequency are determined by an automated perm porometer. Under the conditions explored, the average pore size of meltblown fabrics decreases significantly when the attenuating air pressure increases. Pore size decreases significantly when the take-up speed of the web increases. As expected, an increase in the polymer throughput increases the average pore size. Increasing the DCD initially decreases, then increases pore size. confirming the existence of different "zones" in the space between the die and collector. An increase in the fiber stream approach angle initially decreases, then ...
High-resolution simulations of cylindrical density currents

Three-dimensional highly resolved simulations are presented for cylindrical density currents using the Boussinesq approximation for small density difference. Three Reynolds numbers (Re) are investigated (895, 3450 and 8950, which correspond to values of the Grashof number of 10 5 , 1.5 × 10 6 and 10 7 , respectively) in order to identify differences in the flow structure and dynamics. The simulations are performed using a fully de-aliased pseudospectral code that captures the complete range of time and length scales of the flow. The simulated flows present the main features observed in experiments at large Re. As the current develops, it transitions through different phases of spreading, namely acceleration, slumping, inertial and viscous. Soon after release the interface between light and heavy fluids rolls up forming Kelvin-Helmholtz vortices. The formation of the first vortex sets the transition between acceleration and slumping phases. Vortex formation continues only during the slumping phase and the formation of the last Kelvin-Helmholtz vortex signals the departure from the slumping phase. The coherent Kelvin-Helmholtz vortices undergo azimuthal instabilities and eventually break up into small-scale turbulence. In the case of planar currents this turbulent region extends over the entire body of the current, while in the cylindrical case it only extends to the regions of Kelvin-Helmholtz vortex breakup. The flow develops three-dimensionality right from the beginning with incipient lobes and clefts forming at the lower frontal region. These instabilities grow in size and extend to the upper part of the front. Lobes and clefts continuously merge and split and result in a complex pattern that evolves very dynamically. The wavelength of the lobes grows as the flow spreads, while the local Re of the flow decreases. However, the number of lobes is maintained over time. Owing to the high resolution of the simulations, we have been able to link the lobe and cleft structure to local flow patterns and vortical structures. In the near-front region and body of the current several hairpin vortices populate the flow. Laboratory experiments have been performed at the higher Re and compared to the simulation results showing good agreement. Movies are available with the online version of the paper.
Ceramic membrane reactor for synthesis gas production

Membrane reactors enable synthesis-gas production from methane and air while avoiding the need for separation of the nitrogen either before or after the reaction. A stable membrane was developed by spray deposition of a dense thin film of La0.5Sr0.5Fe0.8Ga0.2O3 − δ on a high-purity porous α-alumina tube. The oxygen permeation rate at 850°C was 2.5 × 10−7 mol·cm−2·s−1. A quartz tube was placed coaxially around the membrane and the shell filled with a rhodium catalyst. Air was fed to the tube and methane to the shell. At 850°C the methane conversion was 97% and the selectivity to carbon monoxide approached 100%. Rapid radial mixing of the oxygen in the shell is essential to prevent coking and undesirable reactions. The membrane decomposes at 780°C in pure CH4, but remains stable up to 970°C in a mixture of 90-mol % CH4 and 10-mol % CO2.
Multi-agent opportunistic planning and plan execution

Multiagent opportunism refers to the ability of agents operating in a multiagent system (MAS) to recognize and respond to potential opportunities for mutual assistance in achieving individual goals. Two major potential obstacles in operationalizing multiagent opportunistic assistance in real-world systems are (i) low amounts of knowledge shared between the agents, and (ii) limited ability of the agents to re-plan dynamically. We have previously shown that even under these limiting conditions, systems of agents can benefit from multiagent opportunism. In this work we discuss how multi-agent systems can exploit shared knowledge for opportunistic predictive encoding using an approach based on an abstract plan representation called partial order plan graphs (POPGs). Further, we present several approaches for increasing system-level performance by improving the efficiency of the plans containing predictively encoded opportunities, as well as the results of an empirical analysis of their impact on the system performance.
Cellular and Molecular Characterization of a Brain-enriched Protein Tyrosine Phosphatase

Regional variations in the expression of a striatal enriched protein tyrosine phosphatase called STEP were studied in the adult rat brain by a combination of immunocytochemistry, lesion studies, Western blotting, and in situ hybridization. Monoclonal antibodies generated against STEP identified multiple polypeptides of M(r) 46, 37, 33 and a doublet of M(r) 64–66 kDa on Western blots. Although the three STEP immunoreactive bands with lower molecular weights were enriched in cytosolic fractions, the 64–66 kDa doublet was enriched in membrane fractions. All of the immunoreactive forms were abundant in the caudate-putamen and were present in lower amounts or were undetectable in other brain regions. In substantia nigra, the M(r) 64–66 kDa doublet was not detected but bands with M(r) 46, 37, and 33 kDa were present. Immunocytochemical and lesion experiments demonstrated that the cytosolic STEP isoforms present in the substantia nigra are in presynaptic axons originating from the projection neurons of the caudate putamen, which innervate this structure. Additional in situ hybridization studies showed that STEP mRNA expression patterns correlate with the patterns of immunocytochemical staining. These findings indicate that there are multiple polypeptide isoforms of STEP enriched in the basal ganglia and related structures which differ in terms of their intracellular locations and functional roles.
Transverse correlation length in thin film media

A method to estimate a transverse correlation length lambda in magnetic thin-film media has been developed. Using a pseudomicrotrack (or filamentary track) analysis, expressions for estimating lambda of the media have been derived. lambda can be determined from the slope of the correlation coefficient of read back signals read at different lateral positions. It was observed that lambda does not strongly depend on the remanent magnetic state for a single-layer medium with strong intergranular coupling but decreases significantly near demagnetization for a multilayer medium. >