cssi/SciSciGPT-SciSciNet huggingface dataset:
Convolution reconstruction of fan beam projections

An algorithm is presented for reordering and interpolating a set of fan beam projections into an equivalent set of equispaced parallel ray projections, which may then be reconstructed by the convolution method of Bracewell and Riddle as implemented by Ramachandran and Lakshminarayanan. This algorithm, is of interest because it opens the possibility of combining high speed parallel data collection with a computationally inexpensive reconstruction algorithm. The required sets of parallel rays are obtained by appropriately selecting single rays from each of several fan beams. A satisfactory balance between the number of rays per parallel ray projection and the number of projections is obtained by the introduction of a “slant” approximation. The restriction of the convolution method to equally spaced rays is then satisfied by a rebinning of the reordered data. Experimental reconstructions of a head projection and simulated data are presented.
Tumor necrosis factor-alpha damages tumor blood vessel integrity by targeting VE-cadherin.

The ability of current antineoplastic agents to cause sustained regression of established human tumors is limited.1,2 One strategy to improve response rates is to use isolation perfusion procedures to improve the therapeutic index of antineoplastic drugs.3 Isolated limb perfusion (ILP) is a surgical procedure in which high-dose chemotherapeutics are recirculated within an extremity primarily to treat in-transit melanoma as well as unresectable soft tissue sarcoma.4 ILP with melphalan alone results in a complete response rate of 54% and an overall response rate of 79% in established melanoma.5 The addition ofhigh-dose human recombinant tumor necrosis factor alpha (TNF) to melphalan ILP augments complete response rates to 75% to 90%.6–8 The ability to cause complete and sustained regressions of established bulky solid human tumors with a single 60- to 90-minute regional treatment with TNF plus melphalan is unique and highlights the importance of elucidating the mechanism of this response.2 Isolation perfusion exposes all of the normal tissue of the extremity to high-dose antineoplastic agents, yet there is a selective destruction only within the tumor. It is well established that melphalan is a DNA alkylating agent and is effective because it causes DNA damage in the dividing cells of the tumor.1 There is evidence that TNF targets the tumor vasculature.10–13 This antivascular effect explains the wide range of histologies that respond to TNF plus melphalan ILP. It is also the primary reason that TNF has the most therapeutic benefit against larger tumors14 as it is not dependent on direct cytotoxicity to the malignant cells.15 The disadvantage of this therapy is that it treats only the extremity and delivers no treatment to the rest of the body in this potentially systemic disease. However, if one could understand the mechanism of this response at a cellular and molecular level, one could hypothesize that alternative strategies that reproduce this mechanism of response with systemic therapy may be developed. Earlier studies have used purely in vitro endothelial cell systems to demonstrate the role of TNF in causing endothelial cell monolayer disruption leading to permeability mediated by the endothelial cell adherence junction protein, VE-cadherin.16–18 The current study is the first of its kind that has used clinical specimens from before and after TNF plus melphalan ILP treatments besides utilizing preclinical in vivo models, and in vitro tumor endothelial cell models to demonstrate that TNF causes tumor selective damage to the vascular integrity mediated by VE-cadherin, which appears to be a molecular target in this effective antitumor therapy.
Metabonomic models of human pancreatic cancer using 1D proton NMR spectra of lipids in plasma

In this study, we hypothesized that the altered insulin and glucose levels in male pancreatic cancer patients reported in a recent JAMA article would result in an altered lipid profile in the blood of pancreatic cancer patients when compared to controls (Stolzenberg-Solomon et al., 2005). Proton nuclear magnetic resonance (NMR) spectra of human lipophilic plasma extracts were used in order to build partial least squares discriminant function (PLS-DF) models that classified samples as belonging to the pancreatic control group or to the pancreatic cancer group. The sensitivity, specificity, and overall accuracy of the PLS-DF models based on 4 bins were 96%, 88%, and 92%, respectively. The sensitivity, specificity, and overall accuracy of the PLS-DF models based on 5 bins were 98%, 94%, and 96%, respectively. The sensitivity, specificity and overall accuracy of both the 4-bin and 5-bin PLS-DF models dropped only 1–2% during leave-25%-out cross-validation testing. Mass spectrometric profiling of phospholipids in plasma found three phosphatidylinositols that were significantly lower in pancreatic cancer patients than in healthy controls. The cancer models are based upon changes in lipid profiles that may provide a more sensitive and accurate diagnosis of pancreatic cancer than current methods that are based upon a single biomarker.
Characterization of Methylaluminoxanes and Determination of Trimethylaluminum Using Proton NMR

New methods for characterization of methylaluminoxanes (MAO) and determination of trimethylaluminum (TMA) using proton NMR are reported. Addition of excess perdeuteriotetrahydrofuran to sharpen and shift the TMA peak followed by curve fitting to remove residual overlap between the TMA and MAO peaks allows accurate, precise, and rapid quantitation of TMA and MAO in solution. The analysis also provides determination of all the solution components of MAO preparations and the number of methyl groups per aluminum in MAO when combined with an independent determination of the aluminum content.
Development of a Predictive Energy Equation for Maintenance Hemodialysis Patients: A Pilot Study

Objective The study objectives were to explore the predictors of measured resting energy expenditure (mREE) among a sample of maintenance hemodialysis (MHD) patients, to generate a predictive energy equation (MHDE), and to compare such models to another commonly used predictive energy equation in nutritional care, the Mifflin-St. Jeor equation (MSJE). Design and Methods The study was a retrospective, cross-sectional cohort design conducted at the Vanderbilt University Medical Center. Study subjects were adult MHD patients ( N = 67). Data collected from several clinical trials were analyzed using Pearson's correlation and multivariate linear regression procedures. Demographic, anthropometric, clinical, and laboratory data were examined as potential predictors of mREE. Limits of agreement between the MHDE and the MSJE were evaluated using Bland-Altman plots. The a priori α was set at P Results The mean age of the sample was 47 ± 13 years. Fifty participants (75.6%) were African American, 7.5% were Hispanic, and 73.1% were males. Fat-free mass (FFM), serum albumin (ALB), age, weight, serum creatinine (CR), height, body mass index, sex, high-sensitivity C-reactive protein (CRP), and fat mass (FM) were all significantly ( P R 2 = 0.489) FFM, ALB, age, and CRP. Two additional models (MHDE-CRP and MHDE-CR) with acceptable predictability ( R 2 = 0.460 and R 2 = 0.451) were derived to improve the clinical utility of the developed energy equation (MHDE-LBM). Using Bland-Altman plots, the MHDE over- and underpredicted mREE less often than the MSJE. Conclusions Predictive models (MHDE) including selective demographic, clinical, and anthropometric data explained less than 50% variance of mREE but had better precision in determining energy requirements for MHD patients when compared with MSJE. Further research is necessary to improve predictive models of mREE in the MHD population and to test its validity and clinical application.
Reptation mechanism in protein-sodium-dodecylsulfate (SDS) polyacrylamide-gel electrophoresis.

Strong evidence has been accumulated from our recent small-angle neutron-scattering and phase-separation studies to support the view that protein--sodium-dodecylsulfate (SDS) complexes in solution are polymerlike objects. This conclusion is also consistent with the viscosimetric measurements of Reynolds and Tanford, if we we further assume that the protein-SDS complex is a free-draining perturbed polymer. We propose here a reptation mechanism for the explanation of the migration of the protein-SDS complex in polyacrylamide gel during electrophoresis. Electrophoretic data taken from independent experiments have been analyzed to confirm our conjecture.
Optimal Degree of Skew in Cooperative Societies

Synopsis. An optimization model is employed to determine the outcome of within-group conflict in cooperative societies. The model assumes that selection acts simultaneously on the stronger, dominant members of the group to secure more benefits for themselves at the expense of subordinates, and on subordinates to leave the group in response to this usurpation if they can do better elsewhere. When it is in the interest of the dominant to maintain the group, the dominant will be limited in its opportunity to bias the benefits in its favor by the options available to subordinates outside the group. The resulting differ? ences in fitness or net pay-off among group members due to usurpation by dominants define the degree of skew. Ecological factors affect both the net benefit of grouping and the options for leaving, and thus establish the limits of skewing. The assumptions and rules governing this interaction are first outlined using a game theory approach. A continuous model for predicting the exact degree of skew is then developed. This analysis shows that the degree of skew increases when the benefit of group breeding relative to solitary breeding increases, and when the degree of relatedness among group members increases. Finally, the trade-offs between breeding with relatives versus nonrelatives are analyzed from a dominant relative's point of view. The results of two empirical studies on a social bird and a social wasp are compared to the predictions of these models. The exceptionally good fit to the models is interpreted as evidence in favor of the "social manipulation" approach to "helpinsr" and "altruism" in cooperatively breeding species.
Increasing Female Participation in Computing: The Harvey Mudd College Story

Over a four-year period, Harvey Mudd College dramatically increased the number of female computer science majors by implementing three innovative changes that other institutions can easily replicate. This is one of five articles providing industry perspectives on gender diversity in computing.
Interactive effects of diluent pH and calcium content on glyphosate activity on Panicum repens L. (torpedograss)

Summary. Solutions of glyphosate containing 0–5 mM calcium, both with buffering (pH 4, 6 or 8) and without, were sprayed onto Panicum repens L. (torpedograss) foliage. Growth inhibition of the treated foliage was poorly correlated with inhibition of shoot regrowth from rhizomes. Therefore, when evaluating long term control of perennial grasses regrowth data should be utilized. Spray solution pH, calcium and glyphosate rate influenced herbicidal activity on torpedograss. Calcium affected glyphosate activity on torpedograss except at the highest herbicide rate (4·48 kg ha−1). Optimum herbicidal activity on torpedograss was achieved with soft water (i.e. no calcium), however, when calcium was present in the spray solution a pH of 6 reduced its antagonistic effects. Resume. Effects interactifs du pH du diluant et de la teneur en calcium sur l'activite du glyphosate sur Panicum repens L. Des solutions de glyphosate contenant 0,5 mH calcium avec un tampon (pH 4, 6 ou 8) ou sans ont ete pulverisees sur le feuillage de Panicus repens L. L'inhibition des parties foliares a ete peu correlee avec l'inhibition du redemarrage de pieds a partir des rhizomes. Ainsi, pour evaluer la destruction a long terme de la repousse des herbes perennes ces donnees pourraient etre utilisees. Le pH de la bouillie de pulverisation et la teneur en glyphosate et calcium ont influence l'activite herbicide contre Panicus repens. Le calcium a affecte l'activite du glyphosate sur P. repens y compris a la plus haute dose de 4,48 kg ha−1. L'activite optimale herbicide a ete obtenue avec de l'eau douce (c'est-a-dire sans calcium), cependant quand le calcium est present dans la solution un pH de 6 reduit les effets antagonistes. Zusammenfassung. Wechselwirkungen des Sauregrads und des Kalziumgehalts auf die Wirkung von Glyphosat auf Panicum repens L. Glyphosat wurde in Losungen mit 0 bis 5 mM Ca, sowohl auf pH=4, 6 oder 8 eingestellt oder nicht, auf Bestande von Panicum repens L. (Torpedogras) ausgebracht. Der Bekampfungserfolg war mit dem Wiederaustrieb aus den Rhizomen schwach korreliert. Bei der Auswertung der anhaltenden Bekampfung ausdauernder Arten sollte deshalb der Wiederaustrieb erfast werden. Der Sauregrad, der Kalziumgehalt und die Aufwandmenge beeinfiusten die Wirkung von Glyphosat auf das Torpedogras. Der Kalziumgehalt beeintrachtigte die Wirkung bei der hochsten Herbizid-Aufwandmenge (4,48 kg ha−1). Die beste herbizide Wirkung wurde mit einer Losung mit weichem Wasser, d.h. ohne Ca, erzielt. Wenn Kalzium in der Spritzflussigkeit enthalten war, wurde seine antagonistische Wirkung durch pH=6 herabgesetzt.
Observation of ballistic transport in the upper subband of a two-dimensional electron system

We report a specially designed transverse magnetic focusing experiment on a two-dimensional electron system confined to a square quantum well with two electric subbands occupied. The reflecting barrier of a usual magnetic focusing device is replaced by a surface-gate-induced, tunable potential barrier that allows us to selectively reflect and magnetically focus the upper subband electrons while the lower subband electrons pass over the barrier and are not focused. We observe the focusing of the upper subband electrons. The weakness of the focusing signal for the upper subband ballistic electrons suggests that they have a surprisingly short ballistic mean free path compared to the lower subband electrons.
Endoscopic endonasal "far-medial" transclival approach: Surgical anatomy and technique

The endoscopic endonasal transclival "far-medial" approach is a safe and effective surgical technique to access the parasagittal inferior third of the clivus. Its indications, advantages, and limitations were previously described. The main objective of this article is to review the relevant surgical anatomy and the operative nuances of the endoscopic endonasal approach to the inferolateral region of the clivus. Anatomical pictures and illustrative cases facilitate its demonstration.
Interactions between eye movements and the visually evoked response in the cat.

Abstract 1. 1. In an attempt to locate the origin of those fed back efferent oculo-motor signals which modify visual perception, the effects of eye movements and eye movement-inducing electrical stimulation on the visually evoked response (VER) in the cat were examined. 2. 2. Stimulation of the IIIrd nerve nucleus produced no detectable effect on the VER. This is in contrast with the reported claims of Fernandez-Guardiola et al. (1964). 3. 3. Eye movements produced by VIIIth nerve stimulation and such stimulation itself led to marked alterations in the wave shape of the VER. This change was not due to blurring of the test flash on the moving retina. 4. 4. VERs produced during spontaneous eye movements showed no difference when compared to their controls. This may well have been due to technical difficulties with the experimental procedures. 5. 5. These results, along with the known properties of saccadic suppression and the organization of the oculo-motor system, are taken to suggest that the midbrain oculo-motor integrating center is the source of the signals which interact with vision.
Advance-Related Sleep Complaints and Advanced Sleep Phase Disorder

Patients with pathologic advance-related sleep complaints live at a circadian phase that is incompatible with their personal and social obligations. Pathophysiologic research is in its early stages, but mutations in various clock genes have been identified among those with familial advanced sleep phase disorder. Various assessment tools, including actigraphic monitoring and morningness-eveningness questionnaires, can complement a thorough clinical history and assist in the attribution of a sleep complaint to a circadian-based entity. Research protocols have demonstrated efficacy with evening phototherapy, which has proven difficult to translate into the clinical arena. Other treatment options include exogenous melatonin, chronotherapy, hypnotics, and, in rare instances, stimulant medications. Proper recommendations regarding avoidance and receipt of light should be provided in all instances.
Response to a mobile health decision-support system for screening and management of tobacco use.

Purpose/objectives To describe the predictors of nurse actions in response to a mobile health decision-support system (mHealth DSS) for guideline-based screening and management of tobacco use. Design Observational design focused on an experimental arm of a randomized, controlled trial. Setting Acute and ambulatory care settings in the New York City metropolitan area. Sample 14,115 patient encounters in which 185 RNs enrolled in advanced practice nurse (APN) training were prompted by an mHealth DSS to screen for tobacco use and select guideline-based treatment recommendations. Methods Data were entered and stored during nurse documentation in the mHealth DSS and subsequently stored in the study database where they were retrieved for analysis using descriptive statistics and logistic regressions. Main research variables Predictor variables included patient gender, patient race or ethnicity, patient payer source, APN specialty, and predominant payer source in clinical site. Dependent variables included the number of patient encounters in which the nurse screened for tobacco use, provided smoking cessation teaching and counseling, or referred patients for smoking cessation for patients who indicated a willingness to quit. Findings Screening was more likely to occur in encounters where patients were female, African American, and received care from a nurse in the adult nurse practitioner specialty or in a clinical site in which the predominant payer source was Medicare, Medicaid, or State Children's Health Insurance Program. In encounters where the patient payer source was other, nurses were less likely to provide tobacco cessation teaching and counseling. Conclusions mHealth DSS has the potential to affect nurse provision of guideline-based care. However, patient, nurse, and setting factors influence nurse actions in response to an mHealth DSS for tobacco cessation. Implications for nursing The combination of a reminder to screen and integration of guideline-based recommendations into the mHealth DSS may reduce racial or ethnic disparities to screening, as well as clinician barriers related to time, training, and familiarity with resources.
DECISION THEORY AND FINANCIAL MANAGEMENT

FINANCIAL DECISION-MAKING involves two separate and distinct considerations: (1) forming probability beliefs about potential returns from various assets and (2) allocating financial resources among assets on the basis of these beliefs. This paper deals exclusively with the second consideration. No effort is made to determine how management forms probability beliefs about returns on investment opportunities; the emphasis of this paper is on the proper financial decisions to be made given such beliefs.
Starting Right: Selecting the Optimum Beginning Placement for Visually Impaired Children

Selecting the most appropriate first grade placement for a handicapped child is difficult. If the child is blind, placement choices may be even more difficult. This article identifies the range of ...
Preparation and properties of poly-9-vinyladenine.

Poly-9-vinyladenine was prepared by reaction of poly-6-chloro-9-vinylpurine with ammonia and poly-1-vinyluracil by hydrolysis of poly-L-vinyl-2-ethoxy-4-pyrimidinone. In aqueous solutions poly-9-vinyladenine shows hypochromism in the ultraviolet spectrum and forms a complex with polyuridylic acid as detected by a further decrease in the ultraviolet absorption. Under the same conditions, poly-9-vinyladenine and poly-L-vinyluracil interact with formation of higher aggregates.
Application of digital tomosynthesis to hand radiography for arthritis assessment

Arthritis is a painful condition with enormous societal impact. Arthritis damages the articular cartilage between adjacent bones in a joint, which is seen radiographically as narrowing of the joint space width (JSW). JSW is an important arthritis outcome measure however a single radiographic image is a 2D projection of a 3D structure and diseased areas can be obscured. To quantify the JSW in three dimensions we have applied digital tomosynthesis imaging to hand radiography. A tomosynthesis algorithm, developed for use in chest radiography, was modified to provide reconstructed slices through the bones that formed joints of the hand. The methodology was tested using simulated radiographs of dry-bone specimens from 3 hand skeletons. Estimates to the JSW in 3D were made from the reconstructed slices. The algorithm produced tomographic slices through the bones of the joint with minimal loss of spatial resolution. We discovered that hand radiography is ideally suited for tomosynthesis imaging due to the small amount of scatter and lack of truncation artifacts. We have demonstrated the utility of digital tomosynthesis for use in quantifying JSW for arthritis assessment. The method shows promise for improving the assessment of disease progression.
Thue congruences and the Church-Rosser property

Finite Thue systems that are Church-Rosser and properties of the semigroups such systems present are studied.
Exploring the Role of Counselor Support: Gay, Lesbian, Bisexual, and Questioning Adolescents Struggling With Acceptance and Disclosure

ABSTRACT Using a qualitative grounded theory approach, support from the high school counselor for GLBQ adolescents was explored. Ten 18- to 21-year-old GLB college students participated in the study. Homophobia and heterosexism were significantly profound barriers to support. Participants feared disclosure forcing their emerging identity as a secret. Internet Chat rooms provided a way to access peer support. The need for counselors to be better educated about GLBTQ issues and use of advocacy skills for the inclusion of GLBTQ adolescents emerged. Being nonjudgmental, ensuring confidentiality, and using ally stickers and GLBTQ-friendly posters emerged as important implications for practice.
The Enigmatic Acyl Carrier Protein Phosphodiesterase of Escherichia coli GENETIC AND ENZYMOLOGICAL CHARACTERIZATION

The acyl carrier proteins (ACPs) of fatty acid synthesis are functional only when modified by attachment of the prosthetic group, 4′-phosphopantetheine (4′-PP), which is transferred from CoA to the hydroxyl group of a specific serine residue. Almost 40 years ago Vagelos and Larrabee (Vagelos, P. R., and Larrabee, A. (1967) J. Biol. Chem. 242, 1776-1781) reported an enzyme from Escherichia coli that removed the prosthetic group. We report that this enzyme, called ACP hydrolyase or ACP phosphodiesterase, is encoded by a gene (yajB) of previously unknown function that we have renamed acpH. A mutant E. coli strain having a total deletion of the acpH gene has been constructed that grows normally, showing that phosphodiesterase activity is not essential for growth, although it is required for turnover of the ACP prosthetic group in vivo. ACP phosphodiesterase (AcpH) has been purified to homogeneity for the first time and is a soluble protein that very readily aggregates upon overexpression in vivo or concentration in vitro. The purified enzyme has been shown to cleave acyl-ACP species with acyl chains of 6-16 carbon atoms and is active on some, but not all, non-native ACP species tested. Possible physiological roles for AcpH are discussed.
Clinical decision support systems in the pediatric intensive care unit.

Objective:To review the use of clinical decision support systems (CDSS) available in the pediatric intensive care unit (PICU).Data Sources:Relevant English language publications indexed in Medline, as well as CDSS-related white papers and texts.Study Selection and Data Extraction:Studies related to
Epithelial and pseudoepithelial differentiation in glioblastoma and gliosarcoma: a comparative morphologic and molecular genetic study.

BACKGROUND. Glioblastomas exhibit a remarkable tendency toward morphologic diversity. Although rare, pseudoepithelial components (adenoid or epithelioid) or true epithelial differentiation may occur, posing a significant diagnostic challenge. METHODS. Hematoxylin and eosin–stained slides were reviewed, and immunohistochemistry and fluorescence in situ hybridization were performed. RESULTS. The patients included 38 men and 20 women. The median age at diagnosis was 57 years (interquartile range [IQR], 50 years-67 years), and the median overall survival was 7 months (IQR, 4 months-11 months). “Adenoid” glioblastomas (A-GBM) predominated (48%). True epithelial glioblastomas (TE-GBM) were next most frequent based on morphology and immunohistochemistry (35%), followed by epithelioid glioblastomas (E-GBM) (17%). Overall, 25 (43%) tumors featured a sarcomatous component. Molecular cytogenetic abnormalities identified by fluorescent in situ hybridization in A-GBM, E-GBM, and TE-GBM, respectively, included p16 deletion/-9 (60%, 71%, 64%); chromosome 10 loss (40%, 63%, 57%), chromosome 7 gain without EGFR amplification (70%, 38%, 40%), EGFR amplification (10%, 50%, 27%), PTEN deletion (10%, 25%, 29%), PDGFRA amplification (10%, 25%, 0%), and RB1 deletion/−13q (50%, 0%, 14%). Abnormalities identified by immunohistochemistry included p21 immunonegativity (60%, 25%, 93%), which was most frequent in TE-GBM (P = .008), strong nuclear p53 staining (29%, 29%, 41%), strong membranous staining for epidermal growth factor receptor (EGFR) (21%, 63%, 19%), which was most frequent in E-GBM (P = .03), and an increased frequency of p27 immunonegativity in gliosarcomas (15% negative, 85% focal) compared with tumors without sarcoma (38% strongly positive) (P = .009). CONCLUSIONS. Pseudoepithelial and true epithelial morphology are rare phenomena in GBM and may be associated with a similar poor prognosis. These tumors demonstrate proportions of molecular genetic abnormalities varying somewhat from conventional GBM. Cancer 2008. © 2008 American Cancer Society.
Simulataneous operation of a free-electron laser on two harmonically related wavelengths

The interaction of light at the fundamental and the third harmonic frequencies in a free-electron laser (FEL) oscillator is explored using the 1-D finite-pulse-mode code HFELP. The code, which assumes that only the TEM00 transverse mode is present at both harmonic frequencies, tracks the temporally-finite pulse electric field amplitudes of the fundamental and the third harmonic as they interact with an rf-linac-generated electron micropulse inside a wiggler. The evolution of the pulse profiles is tracked over many passes through the wiggler and optical resonator, for various initial conditions including frequency-dependent mirror reflectivities. Results include pulse-dependent third-harmonic coherent-spontaneous emission (CSE) with, and without, multiple-pass interference effects; the effects of fundamental sidebands on third-harmonic CSE; and lasing competition between the fundamental and third harmonic in overlapping spatial regions of the electron micropulse.
A pilot study of the impact of animation on decision-making

Recent years have seen the intro duction and growth of graphical animation in simulation. Animation is frequently extolled for its use as a debugging aid, as a communication aid, and as a decision aid. This paper reports on a pilot study that was undertaken to measure the impact of animation as a decision aid. Two versions of a simulation model of a flexible manufacturing system were developed; one with animation and one without.Subjects were given a problem scenario involving a design decision concerning the flexible manufactur ing system. Half were given the animated simulation model as a tool to assist in the design decision and half were given the nonanimated simulation model. The assignment of subjects to type of simulation model was made randomly. The results of the experiment are presented in terms of five variables: decision quality, decision speed, task performance, problem comprehen sion, and viewer preference. Based on this pilot study, suggestions are made for improving the experimen tal desig...
Agroecological foundations of alternative agriculture in California

Abstract Most agricultural regions of California enjoy long growing seasons, fertile soils and irrigantion, all conditions that favor a highly diversified cropping. In addition, the wide variety of vegetables, field and tree crops determined a high diversity and flexibility of agricultural enterprises. Despite these factors, Californian agroecosystems are dominated by monocultural cropping systems. Although productive, these systems lack the ecological features to ensure efficient nutrient cycling, water and soil conservation, and biotic regulation. Productivity is subsidized with chemical inputs such as pesticides and fertilizers, some of which caue undesirable environmental and public health hazards. Large-scale monocultures are also highly susceptible to wind erosion and are dependent on ground water for irrigation, leading in some areas to a considerable ‘ leading in some areas to a considerable ‘overdraft’. In other regions, poor field drainage and rising water are leading to unacceptable soil salinity levels. In summary, Californian agriculture is very productive, but the environmental costs of such productivity is threatening the sustainability of agriculture. The search for self-sustaining, low-input, diversified and energy-efficient agricultural systems is now a major concern of researchers, farmers, policy makers and the public in California. The long tradition in biological pest control in California, as well as the experience of a number of organic farmers who developed low-input systems through ‘trial and error’, provide the building blocks for the search for a more sustainable agriculture. A key strategy is sustainable agriculture is to restore the agricultural diversity of the agricultural landscape. Diversity can be enhanced in lime through crop rotations and sequences, and in space in the form of cover crops, intercropping, agroforestry crop/livestock,mixturee, etc. Vegetation diversification not only results in pest regulation through restoration of natural controls, but also produces optimal nutrient recycling, energy conservation and less dependence on cultural inputs. In California although this new approach to agriculture is actively researched. realistically it will work only if it is economicically sensible and can be carried out within the constraints of a fairty normal agricultural system. Therefore, adoption of recommended diversification designs will procesd as these reduce costs and increase the efficiency and viability of farmers.
Cyber-Physical Vehicle Modeling, Design, and Development

Vanderbilt University introduced a new course in the 2012 Fall Semester: Cyber-physical vehicle modeling, design and development. This course focused on the design, development, fabrication, verification, and validation of a scale vehicle in the virtual and the physical domains to meet a set of realistic and challenging design requirements for the Defense Advanced Research Projects Agency’s Model-Based Amphibious Racing Challenge. The students built a series of models in software and hardware to guide the design choices for the 1/5th scale amphibious vehicle. The culmination of this course was a competition against teams from other universities in January 2013 that compared the vehicle’s actual performance with student-created simulation models. This was an elective course outside the traditional capstone design curriculum and consisted of a team of juniors and seniors across the disciplines of mechanical engineering, electrical engineering, computer engineering, computer science, and physics. The students received robust training “to be an engineer” with many activities that can’t be included in a typical classroom environment: hands-on experience designing, modeling, and building a complete vehicle; simultaneously solving several open ended, rigid deadline challenges; and navigating complex team dynamics in a full end-to-end project. Additionally, the students gained experience using modern engineering modeling tools from the Defense Advanced Research Projects Agency’s META tool suite under development for the Fast, Adaptable, Next-Generation Ground Vehicle program. The META tool suite is a set of free, open source tools for compositional design synthesis at multiple levels of abstraction, design trade space exploration, metrics assessment, and probabilistic verification of system correctness. This work details the course activities and summarizes the lessons learned from a pedagogy perspective.Copyright © 2013 by ASME
Comparison of approaches to the instrumental response function in fluorescence decay measurements

Deconvolution of pulse fluorometry data requires knowledge of the instrumental response, which is not directly observable in some circumstances. Various procedures for approaching the instrumental response function were evaluated for nanosecond fluorescence decay data analyzed by nonlinear least squares, including the commonly used time shift correction and several reference fluorophore methods. A new reference fluorophore technique using a Monte Carlo convolution is introduced and tested. The correction for scattered light in several reference techniques is also presented. The random convolution and one other reference fluorophore method consistently gave superior results over a wide range of experimental conditions.
Comparison of Y-doped Bazro3 thin films for high temperature humidity sensors by RF sputtering and pulsed laser deposition

Abstract This paper presents a comprehensive comparison of the fabrication processing parameters and the electrical, mechanical, chemical, and sensing properties of sputtered and pulsed laser deposited (PLD) Y-doped BaZrO 3 thin films for the use in high temperature (400–650 °C) water vapor partial pressure measurements. RF sputtered thin films with thicknesses of between 200 and 750 nm, at pressures between 0.45 and 50 mTorr and deposition powers between 50 and 300 W were deposited and annealed at 800 °C or 1000 °C for 3 h in air. Correlations between mechanical film stress, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and atomic force microscopy (AFM) stoichiometry data, crystallographic, surface morphology and process and film parameters are presented. Furthermore, the baseline resistivity was characterized as function of film thickness and temperature. PLD samples with thicknesses between 200 and 500 nm were deposited at room temperature to 800 °C. All samples were characterized as deposited. 200 and 500 nm thick samples were also annealed at 1000 °C for 3 h in air and characterized post-anneal. The Ba concentration vs. substrate temperature remained stable within 12–16%, correlating with those Ba concentrations that yield good sensitivity (0.25–8 atm −1 ). The low dependence of the Ba concentration on the deposition parameters indicates that the PLD deposition process allows larger process windows for the deposition of good sensitivity thin film material compared to sputtering. Water vapor partial pressure sensitivity indicated a decrease in sensitivity with decrease in Ba concentration in the films. Partial transition of the Y-doped BaZrO 3 to ZrO 2 and subsequent decrease in oxygen vacancy sites could explain the loss in sensitivity. PLD samples were on average more stable and repeatable and less process dependent, but had lower sensitivity towards humidity. This could be explained by the higher, more stoichiometric and less process dependent Ba concentration of these samples compared to the sputtered samples. At high temperatures (>550 °C) only the PLD samples exhibit stable sensitivity towards humidity. The resulting activation energies for the sputtered samples are only slightly larger than those of the PLD samples at lower temperatures (hole conduction) and much larger at high temperatures (oxygen ion conduction). Annealing of the PLD samples at 1000 °C increases the sensor response time by 10 times and the relaxation time by a factor of 8. Sputtered samples do not survive annealing at 1000 °C. PLD samples also by far outlast sputtered samples in terms of lifetime.
Influence of surface structure on the performance of black-silicon solar cell

The nanotextured silicon surface appears black due to almost complete light trapping in a broad spectral range, which will give rise to high-energy conversion efficiency. However, the complexity of the nanotextured silicon surface enhances the surface recombination and thus usually diminishes the strengths of low light reflection. Nanoscale texturing surface structure is susceptible to changes and such a property allows better opportunities to modify the structure to maximize the advantages of low light reflection, while minimizing the disadvantages of surface recombination. Through the adjustment of nanotextured surface, the performance of a black solar cell can be improved. The purpose of this study is to investigate the impacts of various nanoscale surface structures on the performance of solar cells (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
Invalidity of average squared error criterion in density estimation

The average squared error has been suggested earlier as an appropriate estimate of the integrated squared error, but an example is given which shows their ratio can tend to infinity. The results of a Monte Carlo study are also presented which suggest the average squared error can seriously underestimate the errors inherent in even the simplest density estimations.
Traveling dipole domains in AlGaN/GaN heterostructures and the direct generation of millimeter‐wave oscillations

A new paradigm is presented for the direct generation of self-sustaining millimeter-wave oscillations, based on the piezo- and ferroelectric properties of wurtzite III-nitride materials. In contrast to Gunn diodes which exploit a bulk-like active region, periodic oscillation is achieved in the proposed structures through the creation, propagation and collection of traveling dipole domains supported by fixed polarization charge and the associated two-dimensional electron gas along the plane of a polar heterojunction. State-of-the-art numerical simulation based on the synchronous full-band ensemble Monte Carlo method is applied to study induced oscillations in a simple triode structure commonly used for AlGaN/GaN high electron mobility transistors. (© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
Magnetic anomalies over oceanic structures

The importance of the airborne magnetometer as a geophysical tool in the study of oceanic structures is stressed. Theoretical anomalies of the total magnetic vector are computed for typical oceanic structures to aid in the planning of aerial surveys. These structures are (1) a volcanic island, (2) a crustal fold associated with a negative gravity strip, and (3) a continental border.
Seasonal Cycle–El Niño Relationship: Validation of Hypotheses

The present paper examines ways in which the seasonal cycle influences the evolution of El Nino in the tropical Pacific. The following hypotheses and associated physical mechanisms are investigated: (i) Hy- pothesis 1 (H1)—the seasonal warming of the cold tongue early in the calendar year (January-April) favors the initial growth of an event; (ii) hypothesis 2 (H2)—during an event, the warm surface waters migrating in the western basin from the Southern to the Northern Hemisphere during the northern spring (April-May) trigger enhanced convection along the equator, which contributes to reinforce the event; and (iii) hypothesis 3 (H3)—the warm surface waters returning in the western basin from the Northern to the Southern Hem- isphere toward the end of the calendar year (November-January) favor the demise of ongoing events. Hypothesis-validation experiments are performed with a coupled atmosphere-ocean general circulation model (CGCM)—the tropical Pacific version of the University of California, Los Angeles (UCLA) CGCM. The anomaly-coupling technique is applied, in which the simulated seasonal cycle and interannual variability can be separated and artificially modified to highlight the aspect targeted for examination, thus allowing for comparisons of simulations in which seasonal conditions in the CGCM's atmospheric component are either fixed or time varying. The results obtained in the experiments are supportive of hypotheses H1 and H3. No supportive evidence is found for the validity of hypothesis H2.
All anterior and bileaflet mitral valve prolapses are repairable in the modern era of reconstructive surgery

OBJECTIVE: Although mitral valve repair is the preferred treatment for degenerative mitral valve disease, valve replacement still remains prevalent, particularly in the setting of anterior leaflet prolapse. We sought to determine the feasibility and mid-term durability of a lesion-based surgical strategy applied systematically in a consecutive and nonexclusionary (all comers) series of patients with degenerative mitral valve disease and either isolated anterior leaflet or bileaflet prolapse. METHODS: From January 2002 to December 2010, 188 consecutive patients [mean age 56 ± 14 years (range 12–86), 31% female, mean left ventricular ejection fraction 55 ± 9%] underwent surgery for degenerative anterior mitral leaflet prolapse [isolated (n= 42, 22%) or bileaflet prolapse (n= 146, 78%)]. Degenerative aetiology was Barlow’s disease in 110 (58%) patients and fibroelastic deficiency in 78 (42%). RESULTS: Patients with anterior leaflet prolapse were significantly more symptomatic (New York Heart Association functional Class III–IV) than those with bileaflet prolapse (28.6 vs 9.6%; P= 0.003) at the time of surgery. All patients underwent mitral valve repair and ring annuloplasty. There was 1 immediate valve replacement due to atrioventricular groove bleeding and consequent haematoma in an elderly female patient (99.5% repair rate). Predominant repair techniques were polytetrafluoroethylene neochordoplasty (or loop technique) in 93 (49%) patients, chordal transfer in 86 (46%) and posterior leaflet flip technique in 21 (11%). Median length of stay was 6 (interquartile 5–8) days. In-hospital mortality was 1% (n= 2). Predischarge transthoracic echocardiography showed none to trace mitral regurgitation in 91% of the patients and mild mitral regurgitation in 9%. The Kaplan–Meier estimates for cumulative survival at 1 and 7 years were 98.4 ± 0.9 and 88.7 ± 2.2%, respectively. Freedom from ≥moderate mitral regurgitation was 100% at 1 year, 93.7 ± 2.2% at 4 years and 90.3 ± 3.7% at 7 years. When the interval-censored estimator was used, freedom from ≥moderate mitral regurgitation at 1, 4 and 7 years was 100, 96 and 92%, respectively. CONCLUSION: A lesion-based surgical approach with an intention to repair all degenerative valves with anterior leaflet prolapse was applied to a consecutive series of patients with degenerative mitral valve disease. We were able to achieve a near-100% repair rate. Repair of all degenerative valves may be feasible with good mid-term durability, regardless of valve morphology, patient age or comorbidities.
Mechanical Properties and Fracture Characterization of Cross-Linked PVC Foams:

The tensile stress-strain response and fracture behavior of cross-linked PVC foams have been characterized over a range of foam densities from 36 to 400 kg/m3. The foams were found to be nearly isotropic. Young’s modulus, yield strength and fracture toughness data were compared to micro-structural relations derived for open and closed-cell foams. The failure process and stress strain response were indicative of brittle material behavior. Short gage length tension specimens bonded to aluminum loading blocks showed a tensile strength that increased with decreasing gage length as a result of improved support of the cell-walls of the foam under constrained lateral deformation. The plastic zone size for each of the fracture specimens, estimated from the von Mises yield criterion, was small indicating quasi-brittle failure. Testing of scaled single edged notch bend (SENB) fracture specimens revealed a toughness that decreases with decreasing specimen size.
Temporary Remote Book Storage at the University of Colorado, Boulder Libraries: Facilities Planning, Materials Preparation, Selection, and Retrieval

This paper describes the University of Colorado at Boulder's experience in planning and implementing a temporary off-campus storage facility holding approximately 325,000 volumes. Documentation of the need for storage and communication with teaching faculty is discussed. Key decisions determining the selection of materials to be stored are reviewed as well as the technical processing of those materials. Selection of an appropriate facility and ongoing retrieval of items are also discussed.
Blood pressure in chronic kidney disease: does the emperor have new clothes?

See related article, pp 93–100 Hypertension represents the number 1 risk factor for cardiovascular morbidity and mortality worldwide,1 making its treatment a top public health priority. With continued lower-than-ideal awareness and control rates of hypertension,2 it is perhaps understandable and justifiable that the general attitude toward hypertension and its treatment has been bordering on the overzealous. It is on this background that our thinking about blood pressure (BP)–lowering therapy in chronic kidney disease (CKD) and end-stage renal disease (ESRD) has been shaped for decades. Patients with CKD and ESRD represent some of the highest risk populations, and convictions about the unequivocal role of BP in causing renal and cardiovascular disease have until recently led to opinion-based recommendations to use more stringent treatment targets in these patients.3 In this issue of the journal, Bansal et al4 present an analysis of the association of systolic BP (SBP) levels with all-cause mortality in patients with advanced stages of CKD enrolled in the Chronic Renal Insufficiency Cohort. In patients not on dialysis with estimated glomerular filtration rate <30 mL/min per 1.73 m2, SBP was not associated with mortality; in a subgroup of these patients who advanced to ESRD and …
The Sir2 Family of Protein Deacetylases

▪ Abstract The yeast SIR protein complex has been implicated in transcription silencing and suppression of recombination. The Sir complex represses transcription at telomeres, mating-type loci, and ribosomal DNA. Unlike SIR3 and SIR4, the SIR2 gene is highly conserved in organisms ranging from archaea to humans. Interestingly, Sir2 is active as an NAD+-dependent deacetylase, which is broadly conserved from bacteria to higher eukaryotes. In this review, we discuss the role of NAD+, the unusual products of the deacetylation reaction, the Sir2 structure, and the Sir2 chemical inhibitors and activators that were recently identified. We summarize the current knowledge of the Sir2 homologs from different organisms, and finally we discuss the role of Sir2 in caloric restriction and aging.