cssi/SciSciGPT-SciSciNet huggingface dataset:
An analysis of high-temperature behavior of AA2124/SiC whisker composites

Abstract AA2124/SiC whisker composites were received from a commercial source in the hot-rolled and extruded condition. Tensile and shear tests were carried out on these materials at various temperatures to develop a better understanding of the failure mechanisms involved at high temperatures. It was discovered that the loss in strength of aluminum composites with increasing temperature was mainly caused by a decrease in matrix shear strength. Precipitation kinetics contribute to this loss in shear strength through the re-solution of precipitates at higher temperatures. This information is necessary in the development of aluminum base composites with high-temperature capabilities.
Time-resolved photo and radio-luminescence studies demonstrate the possibility of using InGaN/GaN quantum wells as fast scintillators

In the recent publication by Hospodkova et al, the authors investigate III-N quantum well structures as potential fast scintillators (Hospodkova et al 2014 Nanotechnology 25 455501). The InGaN/GaN quantum well structures are grown using metal organic vapour phase epitaxy on a sapphire substrate and the fast carrier decay times are characterized by time resolved photo and radioluminescence.
Comparison of two different physical activity monitors

Understanding the relationships between physical activity (PA) and disease has become a major area of research interest. Activity monitors, devices that quantify free-living PA for prolonged periods of time (days or weeks), are increasingly being used to estimate PA. A range of different activity monitors brands are available for investigators to use, but little is known about how they respond to different levels of PA in the field, nor if data conversion between brands is possible. 56 women and men were fitted with two different activity monitors, the Actigraph™ (Actigraph LLC; AGR) and the Actical™ (Mini-Mitter Co.; MM) for 15 days. Both activity monitors were fixed to an elasticized belt worn over the hip, with the anterior and posterior position of the activity monitors randomized. Differences between activity monitors and the validity of brand inter-conversion were measured by t-tests, Pearson correlations, Bland-Altman plots, and coefficients of variation (CV). The AGR detected a significantly greater amount of daily PA (216.2 ± 106.2 vs. 188.0 ± 101.1 counts/min, P < 0.0001). The average difference between activity monitors expressed as a CV were 3.1 and 15.5% for log-transformed and raw data, respectively. When a conversion equation was applied to convert datasets from one brand to another, the differences were no longer significant, with CV's of 2.2 and 11.7%, log-transformed and raw data, respectively. Although activity monitors predict PA on the same scale (counts/min), the results between these two brands are not directly comparable. However, the data are comparable if a conversion equation is applied, with better results for log-transformed data.
Adoptive T Cell Transfer for Cancer Immunotherapy in the Era of Synthetic Biology

Adoptive T cell transfer for cancer and chronic infection is an emerging field that shows promise in recent trials. Synthetic-biology-based engineering of T lymphocytes to express high-affinity antigen receptors can overcome immune tolerance, which has been a major limitation of immunotherapy-based strategies. Advances in cell engineering and culture approaches to enable efficient gene transfer and ex vivo cell expansion have facilitated broader evaluation of this technology, moving adoptive transfer from a "boutique" application to the cusp of a mainstream technology. The major challenge currently facing the field is to increase the specificity of engineered T cells for tumors, because targeting shared antigens has the potential to lead to on-target off-tumor toxicities, as observed in recent trials. As the field of adoptive transfer technology matures, the major engineering challenge is the development of automated cell culture systems, so that the approach can extend beyond specialized academic centers and become widely available.
Membrane adhesion in photosynthetic bacterial membranes. Light harvesting complex I (LHI) appears to be the main adhesion factor

We have reconstituted pigment-protein complexes isolated from Rhodopseudomonas palustris photosynthetic membranes into phospholipid liposomes. The various complexes were tested for their ability to promote adhesion of the liposome membrane in the presence and absence of Mg2+ ions. Samples containing a reaction center (RC)/light-harvesting I (LHI) complex appeared to stack in a manner resembling control thylakoids in 2 and 5 mM Mg2+. We also tested for the effects of Mg2+ on detergent extractablity of pigment-protein complexes from intact membranes. Mg2+ sharply reduced the amount of LHI solubilized from membranes, while having little effect on the extractability of the light harvesting II complex (LHII) and the RC. Based on these results we suggest that LHI is the principal adhesion factor of R. palustris thylakoids.
Research traditions in comparative context: A philosophical challenge to radical constructivism

Constructivism in science education has incorporated a multitude of perspectives. Many of these perspectives agree with the general assertion that knowledge is constructed. Two such projects are conceptual change theory and radical constructivism. In this article, I distinguish these two traditions based on four issues: ontology; epistemological commitments; view of learners; and authority of received ideas. I bring a philosophy of science perspective to bear, treating conceptual change theory and radical constructivism as Lakatosian research programs. Through this process the philosophical coherence of the radical constructivist research program is brought into question. © 1997 John Wiley & Sons, Inc.
Influence of Microcracking and Slow Crack Growth on the Planar Coupling Coefficient in PZT

The difference in the planar coupling coefficient, k/sub p/, of two PZT specimens with different grain sizes under the same poling treatment was attributed to a greater tendency for microcracking in the large grain-size specimens. In the absence of microcracking, as shown in small grain-size specimens, the decrease in k/sub p/ and failure of the poled specimens is attributed to slow crack growth. The optimum poling conditions for small grain-size specimens were evaluated in terms of reducing the slow crack-growth effect. 19 refs.
Quantum statistical theory of the ring laser

A unified quantum treatment is presented for bidirectional two-mode ring lasers using the approach of Haken and co-workers. Equations of motion for the reduced density matrix of the field have been derived and used to study the fluctuation properties of the radiation field in different kinds of active media. The steady-state photon number distribution for an inhomogeneously broadened gas ring laser is derived. It is shown that for equal losses the relative fluctuations and normalized cross correlation of the photon numbers approach values 1/3 and -1/3, respectively, for large excitations. For unequal losses the laser may emit typical single-mode laser radiation in the direction of the favored mode and typical equilibrium blackbody radiation in the direction of the weaker mode. Our results generally agree with the predictions of earlier treatments when the losses are equal. However, for unequal losses we predict different behavior for large excitations. Effects of detuning, spatial, and temporal variation of atomic inversion on the fluctuation properties have been investigated in the coherent-state diagonal representation of the density matrix, and steady-state intensity distributions have been derived for various kinds of active atoms. It is shown that for inhomogeneously broadened solid-state ring lasers spatial inhomogeneities may couple themore » modes strongly and the statistical properties of such lasers, characterized by a double-peaked intensity distribution and large relative-intensity fluctuations, may be similar to those of a homogeneously broadened ring laser. Curves are presented to illustrate the behavior.« less
Absorbed-dose beam quality conversion factors for cylindrical chambers in high energy photon beams.

Recent working groups of the AAPM [Almond et al., Med. Phys. 26, 1847 (1999)] and the IAEA (Andreo et al., Draft V.7 of “An International Code of Practice for Dosimetry based on Standards of Absorbed Dose to Water,” IAEA, 2000) have described guidelines to base reference dosimetry of high energy photon beams on absorbed dose to water standards. In these protocols use is made of the absorbed-dose beam quality conversion factor, k Q which scales an absorbed-dose calibration factor at the reference quality 60 Co to a quality Q, and which is calculated based on state-of-the-art ion chamber theory and data. In this paper we present the measurement and analysis of beam quality conversion factors k Q for cylindrical chambers in high-energy photon beams. At least three chambers of six different types were calibrated against the Canadian primary standard for absorbed dose based on a sealed water calorimeter at 60 Co [ TPR 10 20 =0.572, % dd (10) x =58.4], 10 MV [ TPR 10 20 =0.682, % dd (10) x =69.6), 20 MV ( TPR 10 20 =0.758, % dd (10) x =80.5] and 30 MV [ TPR 10 20 =0.794, % dd (10) x =88.4]. The uncertainty on the calorimetric determination of k Q for a single chamber is typically 0.36% and the overall 1σ uncertainty on a set of chambers of the same type is typically 0.45%. The maximum deviation between a measured k Q and the TG-51 protocol value is 0.8%. The overall rms deviation between measurement and the TG-51 values, based on 20 chambers at the three energies, is 0.41%. When the effect of a 1 mm PMMA waterproofing sleeve is taken into account in the calculations, the maximum deviation is 1.1% and the overall rms deviation between measurement and calculation 0.48%. When the beam is specified using TPR 10 20 , and measurements are compared with k Q values calculated using the version of TG-21 with corrected formalism and data, differences are up to 1.6% when no sleeve corrections are taken into account. For the NE2571 and the NE2611A chamber types, for which the most literature data are available, using % dd (10) x , all published data show a spread of 0.4% and 0.6%, respectively, over the entire measurement range, compared to spreads of up to 1.1% for both chambers when the k Q values are expressed as a function of TPR 10 20 . For the PR06-C chamber no clear preference of beam quality specifier could be identified. When comparing the differences of our k Q measurements and calculations with an analysis in terms of air-kerma protocols with the same underlying calculations but expressed in terms of a compound conversion factor C Q , we observe that a system making use of absorbed-dose calibrations and calculated k Q values, is more accurate than a system based on air-kerma calibrations in combination with calculated C Q (rms deviation of 0.48% versus 0.67%, respectively).
Fourier transform approach for the estimation of optical thin film thickness

A parallel is established between an existing empirical procedure for the estimation of thin film thickness by means of optical-density-bandwidth products (ODBWP), and new results derived from a Fourier Transform thin film synthesis approach.
A pooled analysis of coronary arterial patency and left ventricular function after intravenous thrombolysis for acute myocardial infarction

Abstract Individual studies of patency rates and left ventricular (LV) function after thrombolysis have generally been limited by small numbers of observations, wide confidence intervals, and limited numbers of time points. To obtain a more reliable estimate of patterns of patency and LV ejection fraction, a systematic overview of angiographic studies was performed after intravenous thrombolytic therapy. A total of 14,124 angiographic observations from 58 studies evaluating patency after no thrombolytic agent, streptokinase, standard dose tissue-type plasminogen activator (t-PA), accelerated dose t-PA, or anistreplase (anisoylated plasminogen streptokinase activator complex [APSAC]) were included. At 60 and 90 minutes, streptokinase had the lowest patency rates of 48% and 51%, respectively, standard dose t-PA and APSAC had similar intermediate rates of approximately 60% and 70%, and accelerated t-PA had the highest patency rates of 74% and 84%. By 2 to 3 hours and longer, the patency rates were similar for the various regimens. Reocclusion rates in studies including 1,172 patients randomized to t-PA versus a nonfibrin-specific agent were higher after t-PA (13.4% vs 8.0%, p = 0.002). Ten studies enrolling 4,088 patients treated with thrombolytic therapy versus control demonstrated a modest improvement in mean LV ejection fraction in the thrombolytic group at each of the times after thrombolytic therapy: hour 4, day 1, day 4, day 7 to 10, and day 10 to 28 after thrombolysis. By 4 days, mean ejection fraction was 53% versus 47% (thrombolytic vs control therapy, p
Simultaneous diagnosis of acute cholecystitis, intestinal malrotation, and duodenal diverticulum by cholescintigraphy.

A 68-year-old man presented with intermittent episodes of epigastric and right upper quadrant pain and an elevated white blood cell count, 3 months after a hemicolectomy for adenocarcinoma of the transverse colon. Hepatobiliary scintigraphy demonstrated nonvisualization of the gallbladder consistent with acute cholecystitis. In addition, activity within the proximal small bowel revealed malrotation. Delayed imaging also demonstrated a focal area of activity representing a large duodenal diverticulum. Subsequent barium small bowel series and laparotomy with cholecystectomy confirmed all three findings initially noted by scintigraphy
PRODUCTION OF HETEROGENETIC ANTIBODIES WITH MIXTURES OF THE BINDING PART OF THE ANTIGEN AND PROTEIN

1. The alcohol-soluble extract of heterogenetic antigen, which possesses the specific chemical structure of the entire antigen, has a detectable but generally very slight power to increase the amount of heterogenetic antibodies, when injected into rabbits. 2. This substance can be transformed into an efficient antigen by mixing it with protein solutions such as diluted normal serum. 3. Such mixtures are considerably more active than the same substances injected separately. Therefore, the effect of the serum is probably due to the formation in vitro of a loose compound between the alcohol-soluble substance and protein, the compound acting as a complete antigen. 4. It may be supposed that there exists a group of natural antigens which are built up of one specifically reacting part that is almost or entirely devoid of antigenic properties, and another part, a protein, responsible for the immunizing effect.
Performance analysis of a hybrid media streaming system

Recent research efforts have demonstrated the promising potential of building cost-effective media streaming systems on top of peer-to-peer (P2P) networks. A P2P media streaming architecture can reach large size and streaming capacity that are difficult to achieve in conventional server-based streaming services. Hybrid streaming systems that combine the use of dedicated streaming servers and P2P networks were proposed to build on the advantages of both paradigms. However, the dynamics of such systems and the impact of various factors on system behaviors are not totally clear. In this paper, we present an analytical framework to quantitatively study the features of a hybrid media streaming model. Based on this framework, we derive an equation to describe the capacity growth of a single-file streaming system. We then extend the analysis to multi-file scenarios by solving an optimization problem. We also show that the system model achieves optimal allocation of server bandwidth among different media objects. The unpredictable departure/failure of peers is a critical factor that affects performance of P2P systems. To model peer failures in our system, we propose the concept of peer lifespan . The original equation is enhanced with coefficients generated from the distribution of peer lifespan. Results from large-scale simulations support our analysis.© (2003) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Language learning in Down syndrome: The speech and language profile compared to adolescents with cognitive impairment of unknown origin

Children and adolescents with Down syndrome show an emerging profile of speech and language characteristics that is typical of the syndrome (Chapman & Hesketh, 2000; Chapman, 2003; Abbeduto & Chapman, 2005) and different from typically developing children matched for nonverbal mental age, including expressive language deficits relative to comprehension that are most severe for syntax, and, in adolescence, strengths in comprehension vocabulary, improvements in expressive syntax, but losses in comprehension of syntax (Chapman, Hesketh & Kistler, 2002). Here we compare 20 adolescents with Down syndrome to16 individuals with cognitive impairment of unknown origin, statistically matched for age and nonverbal mental age, to show that the age-related strengths in vocabulary comprehension are not limited to the Down syndrome phenotype, but are limited to a certain type of vocabulary test: for both groups, performance on the Peabody Picture Vocabulary Test-3 is significantly greater than performance on the vocabulary subtest of the Test of Auditory Comprehension of Language-3, which does not differ from the syntax comprehension subtests. Vocabulary size, but not conceptual level, is a strength for adolescents with cognitive impairment. In contrast, deficits in auditory-verbal working memory, syntax and vocabulary comprehension, and narration of picture-books without an opportunity to preview them are all specific to the adolescent group with Down syndrome. The expressive language deficit disappears when a preview opportunity and picture support is given.
Three-dimensional direct numerical simulation of soot formation and transport in a temporally evolving nonpremixed ethylene jet flame

Abstract Three-dimensional direct numerical simulation of soot formation with complex chemistry is presented. The simulation consists of a temporally evolving, planar, nonpremixed ethylene jet flame with a validated, 19-species reduced mechanism. A four-step, three-moment, semiempirical soot model is employed. Previous two-dimensional decaying turbulence simulations have shown the importance of multidimensional flame dynamical effects on soot concentration [D.O. Lignell, J.H. Chen, P.J. Smith, T. Lu, C.K. Law, Combust. Flame 151 (1–2) (2007) 2–28]. It was shown that flame curvature strongly impacts the diffusive motion of the flame relative to soot (which is essentially convected with the flow), resulting in soot being differentially transported toward or away from the flame zone. The proximity of the soot to the flame directly influences soot reactivity and radiative properties. Here, the analysis is extended to three dimensions in a temporal jet configuration with mean shear. Results show that similar local flame dynamic effects of strain and curvature are important, but that enhanced turbulent mixing of fuel and oxidizer streams has a first-order effect on transport of soot toward flame zones. Soot modeling in turbulent flames is a challenge due to the complexity of soot formation and transport processes and the lack of detailed experimental soot–flame–flow structural data. The present direct numerical simulation provides the first step toward providing such data.
Fertilizer and Soil Nitrogen Use by Corn and Border Crops in a Strip Intercropping System

Corn (Zea mays L.) has greater yield potential when strip-intercropped than when monocropped, but this potential may be compromised by a failure to understand how N requirements change with row position and the possible N competition of adjacent crops. A four block, completely randomized, split-plot experiment was conducted on a Haig loam soil (fine, smectitic, mesic Vertic Argiaquolls) in southern Iowa, to determine crop utilization of N fertilizer point-injected into corn rows. Nitrogen fertilizer uptake was evaluated in (i) corn rows injected with labeled N fertilizer; (ii) corn rows adjacent to the injected rows; and (iii) plants at the edge of the adjacent soybean [Glycine max (L.) Merr.] and oat (Avena sativa L.)-alfalfa (Medicago sativa L.) strips. Main treatments consisted of three tillage systems: conventional tillage (CT), reduced tillage (RT), and no-till (NT). Subplot treatments consisted of point injection of 15 N-enriched NH 4 NO 3 (67 kg N ha -1 ) in-row at three row positions within the corn strips. Grain and stover yield, Kjeldahl N, and isotope composition of plant materials were determined. Corn yield and labeled-N recovery differed with tillage to the extent that tillage affected early and total season moisture availability. Labeled-N recovery in labeled rows did not differ with row position. Labeled-N recovery in unlabeled rows or crop borders was typically less than 5% of that recovered by labeled rows. Nitrogen is primarily recovered by the row to which it is applied; therefore, row-by-row precision applications seem to be an appropriate management tool.
Effect of inclusion bodies on the buoyant density of recombinant Escherichia coli

During batch culture, buoyant density of recombinant E. coli cells increased linearly as inclusion body per cell increased. This indicated that buoyant density can be used to follow inclusion body formation. This will be helpful to optimize product formation because inclusion bodies are mostly composed of foreign poteins produced by recombinant microorganisms.
New nodal design for high throughput data vortex optical interconnection network

Abstract This paper proposes a new three input nodal structure within the data vortex packet switched interconnection network. With additional optical switches, the modified architecture allows for two input packets in addition to a buffered packet to be processed simultaneously within a routing node. A much higher degree of parallel processing is allowed in comparison to previously proposed enhanced buffer node with two input processing or the original network node with single input processing. Unlike the previous contention prevention mechanism, the new network operates by introducing the packet blocking within the node if no exit path is available. This eliminates the traffic control signaling and the strict timing alignment associated with the routing paths which simplifies the overall network implementation. This study shows that both data throughput and the latency performance are improved significantly within the new network. The study compares the three input node with the two input node as well as the original single input data vortex node. Due to additional switch count and nodal cost, networks that support the same I/O ports and of the same cost are compared for a fair comparison. The limitation introduced by the blocking rate is also addressed. The study has shown that under reasonable traffic and network condition, the blocking rate can be kept very low without introducing complex controls and management for dropped packets. As previous architectures require operation under saturation point, the proposed architecture should also operate at reasonable level of network redundancy to avoid excessive packet drop. This study provides guidance and criteria on the proposed three input network design and operation for feasible applications. The proposed network provides an attractive alternative to the previous architectures for higher throughput and lower latency performance.
Recruitment of N-type Ca2+ channels during LTP enhances low release efficacy of hippocampal CA1 perforant path synapses

The entorhinal cortex provides both direct and indirect inputs to hippocampal CA1 neurons through the perforant path and Schaffer collateral synapses, respectively. Using both two-photon imaging of synaptic vesicle cycling and electrophysiological recordings, we found that the efficacy of transmitter release at perforant path synapses is lower than at Schaffer collateral inputs. This difference is due to the greater contribution to release by presynaptic N-type voltage-gated Ca(2+) channels at the Schaffer collateral than perforant path synapses. Induction of long-term potentiation that depends on activation of NMDA receptors and L-type voltage-gated Ca(2+) channels enhances the low efficacy of release at perforant path synapses by increasing the contribution of N-type channels to exocytosis. This represents a previously uncharacterized presynaptic mechanism for fine-tuning release properties of distinct classes of synapses onto a common postsynaptic neuron and for regulating synaptic function during long-term synaptic plasticity.
Patient preference for a mandibular complete denture with a broad or minimal base: a preliminary report.

lh b e asic requirements of the properly extended denture base have been documented and published in many standard prosthodontic textbooks. It is generally accepted that well-placed denture borders provide peripheral seal, and thus, greater retention and stability are attained. However, more important is the fact that correct extensions of the denture base result in greater distribution of stress. The forces of mastication then are distributed over the widest supporting area, and the forces on local areas are minimized. This enables the patient to chew a greater variety of foods with more comfort and with less possibility of ridge trauma and bone loss. Nevertheless, due to design or to possible patient demand, many dentures are made with grossly underextended borders. It is a rational assumption that the average denture patient would prefer to have his teeth replaced with the least amount of material. Patients who wear mandibular dentures often object to the retromylohyoid flange, the buccal flange, and the denture base that covers the retromolar pad. These areas never have contact with foreign material and also were never covered if the patient wore a fixed or a tooth-supported removable partial denture. All too often, even the distal-extension partial denture has minimally extended borders as excessive dependence is placed on the remaining teeth for retention and support. The presence of a new denture with correctly extended borders requires the patient to make a gross adjustment in the oral environment. Complaints of difficulties in speech, mastication, swallowing, and other areas are common.
Identification and functional reconstitution of phosphate: sugar phosphate antiport of Staphylococcus aureus.

Resting cells ofStaphylococcus aureus displayed a phosphate (Pi) exchange that was induced by growth with glucose 6-phosphate (G6P) orsn-glycerol 3-phosphate (G3P). Pi-loaded membrane vesicles from these cells accumulated32Pi, 2-deoxyglucose 6-phosphate (2DG6P) or G3P by an electroneutral exchange that required no external source of energy. On the other hand, when vesicles were loaded with morpholinopropane sulfonic acid (MOPS), only transport of32Pi (andl-histidine) was observed, and in that case transport depended on addition of an oxidizable substrate (dl-lactate). In such MOPS-loaded vesicles, accumulation of the organic phosphates, 2DG6P and G3P, could not be observed until vesicles were preincubated with both Pi anddl-lactate to establish an internal pool of Pi. Thistrans effect demonstrates that movement of 2DG6P or G3P is based on an antiport (exchange) with internal Pi.
Comparative bactericidal activity of penicillin-netilmicin and penicillin-gentamicin against enterococci

The synergistic bactericidal activity of netilmicin in combination with penicillins was compared with that of gentamicin and streptomycin against 16 clinical isolates of enterococci. In a macrodilution chessboard assay against multiple combinations of penicillin, gentamicin and netilmicin, bactericidal activity uniformly occurred at two- to four-fold lower concentrations of penicillin + netilmicin than with penicillin + gentamicin. With four strains, penicillin + netilmicin produced up to ten-fold greater killing than penicillin + gentamicin after 6 h of incubation. With one strain, 3 X log10 greater killing occurred with netilmicin after 24 h. Netilmicin was two- to four-fold more active than gentamicin when combined with penicillinase-resistant penicillins. The bactericidal activity of netilmicin against enterococci is equal to or greater than that of gentamicin, either alone or when combined with penicillins.
Disconnect and capture of education decentralisation reforms in Nepal: implications for community involvement in schooling

This article argues that processes of disconnect and capture have affected Nepal's efforts to decentralise its education system, leading to a failure to engage the very stakeholders – parents and communities – that the reforms sought to reach. Specifically, disconnect occurred in the development and implementation of the latest ‘decentralisation’ reforms because they were formulated via a highly centralised policy-making process and then implemented from the top down. As a result, they had little impact on community-level school leadership or ownership, and led to a continued exclusion of the very community-level stakeholders that the reforms sought to engage. Furthermore, the policy reforms have also led to an increased central legitimisation and empowerment of school management committees, which in turn has facilitated the capture and politicisation of these bodies by locally established leaders who are often not motivated to engage parents and community members in school reform. While these processes a...
Anthropometric studies of the long bones of the “shell mound” Indians

The “shell mound” Indians exhibit both sexual and bilateral variations in comparative long bone lengths. Mean long bone lengths are shortest in the Indian group when compared to those reported for both Caucasians and Negroes. The radiohumeral and humero-femoral indices of the “shell mound” Indians are higher than those reported for either Caucasians or Negroes. There is a relatively high degree of anterior-posterior curvature of the femur in the Indian group when compared to the femora of Caucasian and Negroes. There is apparently no correlation between maximum femoral length and trochanter length in comparing right and left sides in either sex. The collo-diaphyseal angles are greater on the average on the left side in both sexes. The femora of male “shell mound” Indians exhibits greater average collo-diaphyseal angles than do the femora of male Caucasians.
Glycosaminoglycan inhibition of collagen induced platelet aggregation

Abstract Chondroitin 6-sulfate (Ch6-S), a glycosaminoglycan (GAG), has been shown to inhibit collagen fibrillogenesis and collagen induced platelet aggregation. Complexation of soluble microfibrillar collagen with Ch6-S at low pH followed by saline dialysis results in the stabilization of 300A wide microfibrillar aggregates with no banding in the electron microscope. These structures, which may be intermediates in collagen fibrillogenesis, do not aggregate platelets or cause serotonin release, whereas fibrils formed from uncomplexed microfibrillar collagen induce platelet aggregation and serotonin release. Neutral complexation of microfibrillar collagen with Ch6-S does not inhibit fibril formation or platelet aggregation. Soluble Ch6-S does not interfere with platelet aggregation in response to soluble microfibrillar collagen, indicating that Ch6-S does not block sites on the platelet membrane or on collagen fibrils which may be specifically involved in the collagen-platelet interaction. These results imply that GAG complexes with collagen may be suitable as blood compatible materials.
The Relative-Autonomy State Theory and Emancipatory Strategies1

L'A. examine de facon critique la these defendue par Melanie DuPuis dans son article «Pacification or Contestation? The Role of Discourse in Agricultural Policy» publie en 1999. Il rappelle que DuPuis distingue theorie instrumentale de l'Etat et theorie de l'autonomie relative de l'Etat. Il estime que les legislations et les interventions regulatrices de l'Etat, a partir du moment ou elles limitent les incertitudes, servent les interets des entreprises capitalistes. Il decrit de quelle maniere l'Etat federal americain envisage l'interet general dans les textes legislatifs en matiere d'agriculture et d'environnement. Il montre que la promulgation de lois sur la protection de l'environnement, aux Etats-Unis, ne debouche jamais sur la mise en place de mesures concretes. Il considere que l'incapacite de l'Etat a elaborer des mesures fiables en matiere environnementale ne peut que favoriser la contestation au sein de la societe civile.
Influence of Hispanic ethnicity on outcome after resection of carcinoma of the head of the pancreas.

BACKGROUND Poor outcomes in Hispanic patients have been reported for tumors at a number of sites. The authors sought to determine whether a similar phenomenon occurs in Hispanics after the resection of solid epithelial tumors of the head of the pancreas. METHODS Between 1983–1995, 273 patients with noncystic epithelial carcinoma of the head of the pancreas were evaluated. Resection was accomplished in 104 patients (38%); these patients were the focus of the current retrospective review. Of the patients who underwent resection, 26 (25%) were Hispanic and 78 (75%) were non-Hispanic. RESULTS Although Hispanic patients tended to present at a significantly younger age and their serum bilirubin level was significantly higher, no other differences in clinical characteristics were observed. After resection, Hispanic patients had a median survival of only 11.4 months, whereas the non-Hispanic group had a median survival of 21.7 months (P = 0.009). Hispanic ethnicity, as well as age > 74 years and jaundice at the time of presentation also were found to be significant prognostic factors on multivariate analysis. Hispanic patients did not present with more advanced disease and no delays in assessment by a physician or in proceeding to surgery were observed. Furthermore, the rate of resection was the same in Hispanic patients and non-Hispanic patients. Long-term survival after palliative bypass was similarly worse in the Hispanic subgroup. CONCLUSIONS Hispanic patients treated at the study center appeared to have a diminished survival after resection of a tumor of the head of the pancreas. No treatment-related factors were identified that could explain this discrepancy in outcome. Cancer 2001;91:1177–84. © 2001 American Cancer Society.
Social Capital in Engineering Education

Universities set goals for their graduates to perform in the workplace as well as to be responsible citizens. Students are required to not only develop a mastery of a particular subject, but civic, social and workplace skills as well. Achieving these goals is constrained by time and an academic atmosphere of individualism and competition. Traditional approaches to curriculum designed to develop only subject specific skills are no longer appropriate and adequate to satisfy these criteria. This paper argues that universities must develop student social capital. Social capital consists of social networks, pro-social norms, and the value of these networks and norms. The value of social capital has been investigated in multiple contexts such as business, economics, and sociology and the presence of social capital has been positively correlated with low crime levels, high educational attainment, retention in college and K-12, and perhaps most intriguing for engineering education, innovation and productivity in knowledge-based firms. This work presents a summary of existing literature discussing social capital that is relevant to engineering education, from business and academic settings, and utilizing this literature base suggests that engineering education curriculum be designed in terms of developing both human capital and social capital. Additionally, social learning theories are discussed that inform the view that student learning should be centered around active social involvement, including pro-social norms such as trust and reciprocity. Several educational methods are discussed that have been shown to increase student social capital, such as cooperative learning and service learning
Work in progress - outreach and retention in the University of Utah Engineering programs

For several decades, college student retention research has focused on the importance of engaging college students in their higher education environment as a tool for helping them attain their degrees. Student Affairs administrators across the United States have incorporated the idea of engagement in their programs and services to increase student retention. This work in progress paper describes how the College of Engineering at the University of Utah has incorporated the concept of engagement into its retention efforts in response to a shortage of engineers in the state. Engagement efforts in this National Science Foundation funded project include participation in outreach teams, facilitating a summer innovation summit, participating in learning community courses, and implementing service learning. The paper focuses on unique elements of the program, incorporating qualitative evaluation data from the first year of the project to describe how lessons learned have shaped second year efforts.
Endoscopic resection of a giant esophageal polyp: case report and review of the literature.

Fibrovascular esophageal polyp, also referred to as giant esophageal polyp, is a very rare benign neoplasm and represents the most common intraluminal tumor of the esophagus. It usually manifests with dysphagia and weight loss, but could be as dramatic as regurgitation of the polyp through the mouth or asphyxiation. The difficulty involved in the interpretation of radiological and endoscopic findings is responsible for frequent mistakes in its diagnosis. Here, we present the case of a patient with a 20-cm-long esophageal polyp located below the upper esophageal sphincter that was removed using an endoscopic approach. We review the recent literature and describe the various diagnostic and therapeutic methods to diagnose and manage this benign but potentially life-threatening entity.
The relationship between pay and job satisfaction: A meta-analysis of the literature

Abstract Whereas the motivational aspects of pay are well-documented, the notion that high pay leads to high levels of satisfaction is not without debate. The current study used meta-analysis to estimate the population correlation between pay level and measures of pay and job satisfaction. Cumulating across 115 correlations from 92 independent samples, results suggested that pay level was correlated .15 with job satisfaction and .23 with pay satisfaction. Various moderators of the relationship were investigated. Despite the popular theorizing, results suggest that pay level is only marginally related to satisfaction. Theoretical and practical implications of the results are discussed.
Patterns in Square Arrays of Coupled Cells

In recent years it has been observed that reaction]diffusion equations Ž . with Neumann boundary conditions as well as other classes of PDEs possess more symmetry than that which may be expected, and these ‘‘hidden’’ symmetries affect the generic types of bifurcation which occur Ž w x w x w x see Golubitsky et al. 6 , Field et al. 5 , Armbruster and Dangelmayr 1 , w x w x . Crawford et al. 2 , Gomes and Stewart 8, 9 , and others . In addition, equilibria with more highly developed patterns may exist for these equaw x tions than might otherwise be expected. Epstein and Golubitsky 4 show that these symmetries also affect the discretizations of reaction]diffusion equations on an interval. In particular, equilibria of such systems may have well-defined patterns, which may be considered as a discrete analog of Turing patterns. w x In this paper, we use an idea similar to the one in 4 to show that the same phenomena occurs in discretizations of reaction]diffusion equations on a square satisfying Neumann boundary conditions. Such discretizations lead to n = n square arrays of identically coupled cells. By embedding the original n = n array into a new 2n = 2n array, we can embed the Neumann boundary condition discretization in a periodic boundary condition discretization and increase the symmetry group of the equations from
Trans-activation, post-transcriptional maturation, and induction of antibodies to HERV-K (HML-2) envelope transmembrane protein in HIV-1 infection.

Background Human Endogenous Retroviruses (HERVs) comprise about 8% of the human genome and have lost their ability to replicate or to produce infectious particles after having accumulated mutations over time. We assessed the kinetics of expression of HERV-K (HML-2) Envelope mRNA transcript and surface unit (SU) and transmembrane (TM) subunit proteins during HIV-1 infection. We also mapped the specificity of the humoral response to HERV-K (HML-2) Envelope protein in HIV-1 infected subjects at different stages of disease, and correlated the response with plasma viral load.
Physician personality characteristics and inquiry about mood symptoms in primary care.

Depression treatment is often initially sought from primary care physicians. To explore the influence of physician personality on depression assessments. Secondary analysis of data collected in a randomized controlled trial. Offices of primary care physicians in Rochester, NY. Forty-six physicians; six female actors. Eighty-six unannounced standardized patient (SPs) visits; physicians saw one SP with major depression and one with adjustment disorder. SPs listened to audiotapes and completed a form on doctoring behaviors and symptom inquiry immediately following the visit. For the assessment of diagnostic documentation, SPs’ medical records were reviewed. Physician personality was assessed via items from the NEO-PI-R. Physicians who are more dutiful and more vulnerable were more likely to document a diagnosis of depression; those who are more dutiful also asked fewer questions concerning mood symptoms. Roles portrayed by the SPs may not reflect the experience of a typical primary care patient. Most of the PCPs were white men. The sample of PCPs was limited to a single geographic location. Effect sizes were modest. The clinical, educational, and translational, implications of research showing that physician personality traits could affect practice behaviors warrant consideration. Current models of treatment for depression in primary care could be engineered to accommodate the variability in physician personality. Given that there is no single “correct” way to ask about mood disorders or suicide, clinicians are encouraged to adopt an approach that fits their personal style and preferences.
Reproduction in mice: Spermatozoa as factors in the development and implantation of embryos

The effects on mouse embryo development in vivo of varying the numbers of spermatozoa used in artificial inseminations was studied. The two criteria used in the evaluation of the progress of embryo development were 1) ability to reach the two-cell stage and 2) success of development from the two-cell stage through implantation. A 44% reduction in the yield of two-cell embryos and a 67% reduction in the number of implants was observed when C3HeB/FeJ females were inseminated with one-twentieth the number of spermatozoa estimated to be present in a typical ejaculate. The reduction in the yield of two-cell embryos was substantially reversed by a second insemination of a large number of heat-inactivated spermatozoa 12 hr after the first insemination. The sperm-dependent reduction in development from the two-cell stage through implantation was prevented only by normal viable (unheated) spermatozoa. These results were rationalized by the hypothesis that in female C3HeB/FeJ mice spermatozoa serve physiological functions beyond the fertilization of ova and that spermatozoa may act to foster early embryo development through modulation of the environments embryos experience as they move through the reproductive tract.
Using particles to sample and control implicit surfaces

We present a new particle-based approach to sampling and controlling implicit surfaces. A simple constraint locks a set of particles onto a surface while the particles and the surface move. We use the constraint to make surfaces follow particles, and to make particles follow surfaces. We implement control points for direct manipulation by specifying particle motions, then solving for surface motion that maintains the constraint. For sampling and rendering, we run the constraint in the order direction, creating floater particles that roam freely over the surface. Local repulsion is used to make floaters spread evenly across the surface. By varying the radius of repulsion adaptively, and fissioning or killing particles based on the local density, we can achieve good sampling distributions very rapidly, and maintain them even in the face of rapid and extreme deformations and changes in surface topology.
Target prescreening based on 2D gamma kernels

This work develops and tests a new target prescreening algorithm based on 2D gamma kernels. The key feature of the new kernel set is the existence of a free parameter that determines the size of its region of support. We show that the scale affects the false alarm rate of the two parameter CFAR test. We also show that a linear discriminant funtion composed from the linear and quadratic terms of the intensity in the test cell neighborhood improves the false alarm rate when compared with the two parameter CFAR.
Transient depletion of B cells in young mice results in activation of regulatory T cells that inhibit development of autoimmune disease in adults

B-cell depletion therapy can be effective for treating B-cell lymphomas as well as many human and murine autoimmune diseases. B-cell-deficient mice are normally resistant to spontaneous autoimmune thyroiditis (SAT), but they develop SAT if regulatory T cells are transiently depleted during the first 3‐6 weeks after birth. This was also a critical time when B-cell depletion effectively inhibited development of SAT in adult mice. The current study was undertaken to test the hypothesis that transient depletion of B cells using anti-CD20 would be sufficient to suppress SAT if B cells were depleted early in life and that inhibition of SAT would be due to the activity of Treg that functioned most effectively when B cells were absent or low. The results presented here support this hypothesis and indicate that development of autoimmune disease in adults is effectively inhibited when anti-CD20 is administered 1‐3 weeks after birth. After 3 weeks, transient B-cell depletion is no longer effective, and B-cell depletion must be maintained to effectively suppress autoimmune disease. B-cell depletion in 1- to 3-week-old mice depletes all B-cell subsets, whereas B-cell depletion initiated in adults spares many marginal zone B cells. Following early B-cell depletion, splenic Treg increase in number, and depletion of Treg reverses the inhibitory effect of anti-CD20 on disease development. Early transient depletion of B cells could be useful for preventing autoimmune disease in individuals at high risk for developing autoimmune diseases as adults.
Today's Cutting Edge is Tomorrow’s Obsolete: An Interview with Cory Arcangel and Tina Kukielski

Exhibited at the Carnegie Museum of Art, Pittsburgh from November 3, 2012 to January 27, 2013, Cory Arcangel: Masters was a wide-ranging, multi-sensory survey of the artist’s major works to date. The following interviews with Arcangel and the exhibition’s curator Tina Kukielski were conducted in February 2013, and discuss the conceptual, curatorial, and aesthetic issues raised by the exhibition.