cssi/SciSciGPT-SciSciNet huggingface dataset:
Percutaneous transapical access to facilitate complex thoracic endovascular aortic repair.

Abstract Thoracic endovascular aortic repair (TEVAR) provides an alternative to open surgery for a variety of aortic diseases. However, complex anatomy and previous operations may preclude traditional approaches to TEVAR. Percutaneous transapical access through the left ventricle is a feasible option to facilitate externalized "rail" wire support for complex TEVAR. We present the case of TEVAR for a residual type B aortic dissection facilitated by percutaneous transapical access.
Positive surgical margins at radical prostatectomy in the United States: Institutional variations and predictive factors

Abstract Introduction Positive surgical margins (PSMs) are associated with treatment failure after radical prostatectomy (RP) for patients with prostate cancer (CaP). We investigated institutional variations in PSM after RP, as well as clinical and demographic factors predicting PSM. Patients and methods Patients undergoing RP for clinically localized CaP were identified in the National Cancer Database in 2010 to 2013 and clinicodemographics were recorded. Treating institution was defined as academic (AMC) or nonacademic medical centers (nAMC). The primary outcome was the PSM rate. Multivariable logistic regression and propensity matching with inverse probability treatment weighing were used to both compare outcomes between AMC and nAMC and to identify predictors of PSM following RP. Results A total of 167,260 patients met our inclusion criteria. PSM rate was significantly lower in patients treated at AMC (13,435, 18.9%) compared with 22,145 (23.0%) in those treated at nAMC (P Conclusion PSM rates appear to be lower at AMC and higher volume facilities, which can potentially reflect institutional differences in surgical quality. In addition, we identified several socioeconomic and demographic factors that contribute to the likelihood of PSM following RP for localized CaP, suggesting potential systematic variation in the quality of surgical care. The cause of this variation warrants further investigation and evaluation.
Epstein-Barr Virus in Patients with Chronic Lymphocytic Leukemia.

Abstract Purpose: The Epstein-Barr virus (EBV) is implicated in the development of Richter's transformation in patients with chronic lymphocytic leukemia (CLL)/small lymphocytic lymphoma (SLL). The objective of this study was to assess the incidence and the clinical significance of EBV in patients with CLL/SLL. Patients and Methods: Patients with CLL/SLL who presented at The University of Texas M. D. Anderson Cancer Center over a two-year period, and had available marrow paraffin blocks were studied for evidence of EBV infection using a highly specific in-situ hybridization assay for detection of EBV encoded RNA (EBERs). Results were analyzed in relation to other presenting characteristics and outcome. Results: Thirty-two patients were examined. EBERs were detected in 12 of 32 (38%) CLL/SLL marrows versus 0 of 20 normal marrows (p = 0.002). EBERs were observed in sporadic granulocytes alone or in addition to its presence in lymphocytes in nine of the twelve EBV-positive patients. EBERs were detected less frequently in patients with Rai stage 0-1 disease (20%) compared with Rai stage 2–4 (66%; p=0.008); EBER-positive patients tended to have higher lactate dehydrogenase (LDH) levels (p=0.053). The 10-year survival rate was 22% versus 58% for patients with and without discernible EBERs (log-rank, p=0.08). Download : Download high-res image (91KB) Download : Download full-size image Conclusions: Evidence of EBV infection was found in 38% of CLL/SLL patients assessed. Despite the small number of patients tested, discernable EBERs were significantly more common in individuals with more advanced Rai stage, and there was a trend toward shorter survival in patients in whom EBV EBERs were discerned. Larger studies are needed to determine the prognostic value and role of EBV infection in patients with CLL/SLL.
P68 The management of acute wheeze- what do paediatric trainees do?

Background Current guidelines of acute management of wheeze in children are open to interpretation (Keeley:2018). Individual clinician preference and many ‘local guidelines’ influence the initial management by the frontline paediatric trainees. We hypothesised that there is greater variation in practice with acute preschool wheeze than the school age children with acute asthma. Methods Online survey of paediatric trainees in West Midlands using three clinical scenarios of children of different ages presenting with acute wheeze. Trainees were asked to select the most appropriate management plan out of giving inhalers, nebulisers or ‘back to back therapy’. Following reassessment trainees were then asked for the next line of treatment Results 82 responses from ST1-ST8 trainees between March and July 2019. 85% were managing at least one child with wheeze every day.66% of respondents had a minimum of 3 years of paediatric experience. In a pre-school child with wheeze and saturations of 94%, 77% of trainees gave 10 puffs of salbutamol as initial treatment. 34% would give 2 further bronchodilators ‘back to back’ after initial improvement. In both cases of older children with asthma, half of trainees gave a nebuliser an initial therapy despite the oxygen saturations >92% at presentation. 20% of respondents understand the term ‘back to back’ to mean an interval of between 15 and 30 minutes. 97% of trainees give written wheeze information to families with 87.5% opting for 3 day salbutamol weaning plan at discharge. Conclusions Contrary to our hypothesis, the survey demonstrates that there is more consistency in the initial management of preschool wheeze compared to older children with asthma. This may reflect the service pressures to decide about admitting or discharging the child rather than an uncertainty about clinical situation. In older children where clinical assessment is more predictable, surprisingly, half of the trainees administered nebulised bronchodilators despite normal oxygen saturations. Older children may have had inhalers for a period of time (not acknowledged in current BTS guidelines) prompting trainees to take a different approach. Discharging children with a Salbutamol weaning plan is unique to the UK practice (Levy:2018) which needs to be addressed by prospective studies.
Beta Adrenoceptor Ligands for the Treatment of Group 3 Pulmonary Hypertension and Cor Pulmonale: A Novel Therapeutic Target?

Purpose Pulmonary hypertension is a common complication of idiopathic pulmonary fibrosis (IPF), which leads to cor pulmonale and right-heart failure. β-blockers have been used extensively for the treatment of left heart disease, yet their use for right-heart failure is controversial. Recent studies have shown that β-blockers may be beneficial for the treatment of pulmonary arterial hypertension. However, whether β-receptors ligands are effective in PH and cor pulmonale associated with lung fibrosis has not been evaluated. Here we tested the effects of β adrenergic receptors (βAR) ligands in an experimental model of lung fibrosis and PH where fibrotic injury and cardiovascular complications co-exist. Methods Using lung tissues isolated from explanted lungs from patients with IPF (with and without a diagnosis of PH), we determined βAR gene expression levels. Next, the capacity of either carvedilol (a βAR blocker) or clenbuterol (a β2AR agonist) to improve bleomycin (BLM)-induced alterations in cardiovascular physiology or lung function were assessed. These experiments were performed using lung function and transthoracic Echocardiography (Fig 1). After completion of these physiological readouts, the lungs were excised for assessment of fibrotic injury by RT-PCR, immunoblots and histology. Results Our experiments demonstrate reduced expression levels of the β2AR, but not β1AR or β3AR in IPF lung vs controls. We also report a significant correlation between elevated mPAP and reduced β2AR expression. Remarkably, our results using carvedilol or clenbuterol revealed that these agents improved right-heart function without impacting lung function. Conclusion Taken together, these results demonstrate that β-receptor ligands are able to treat PH and cor pulmonale associated with lung fibrosis without altering fibrotic matrix deposition. These results are significant since PH is the single most significant predictor of mortality in IPF where limited therapies exist.
Seeing Red: Blood Sample Hemolysis Is Associated with Prolonged Emergency Department Throughput.

INTRODUCTION Hemolyzed emergency department (ED) blood specimens impose substantial burdens on various aspects of delivering care. The ED has the highest incidence of hemolysis among hospital departments. This study assessed the association and potential impact of hemolyzed blood samples on patient throughput time using ED length of stay (LOS) as the primary outcome measure. METHODS This study was a secondary analysis of data collected during a performance improvement project aimed at reducing the incidence of hemolysis in ED blood specimens. The electronic medical record was queried for potassium orders and results and for key patient throughput time points. Throughput times were stratified according to hemolysis, ED disposition (admitted vs discharged), and Emergency Services Index (ESI) triage categorization. Two-tailed t tests were used to compare throughput times for patients with and without hemolysis. RESULTS Potassium values were reported for 11 228 patient visits. The mean ED LOS was 287 minutes for patients with nonhemolyzed samples and 349 minutes for patients who had hemolyzed samples, a mean delay of 62 minutes. The mean throughput time for discharged patients was 92 minutes shorter in the group without hemolysis (337 vs 429 minutes). The mean throughput time for admitted patients was 28 minutes shorter in the group without hemolysis (264 vs 292 minutes). The increased LOS for patients with a hemolyzed blood sample was independent of the most commonly encountered ESI levels. CONCLUSION Hemolysis of blood samples obtained in the ED is associated with prolonged patient throughput via delays in patient disposition, independent of various markers of acuity, such as the patients' ultimate disposition or triage categorization.
Afterword: Lives interrupted, trends continued?

The COVID-19 pandemic is nowhere near over Some things, however, seem relatively clear So far, the agendas of the world's most powerful actors seem unchanged-or, indeed, accelerated Partly as a result, disease mortality and economic losses have fallen largely on poorer people, though deaths so far have been concentrated among poorer people in rich countries Consequently, the pandemic's implications look very different at the local, subnational, and international levels-although at all levels, they thus far reflect accelerations of preexisting trends more than new departures Many developments reflect remarkable gains in human capacity to cope with disasters-a point highlighted by comparisons to the 1919 flu and other historical events pandemics made by the authors in this forum Those gains are particularly evident in Asia, though they look more precarious in South Asia and Southeast Asia than in East Asia;this has contributed to a marked shift in rhetoric about global “sickness” and health and seems consistent with prophecies of a coming “Asian century ” However, COVID-19 may not be a singular event like 1919 but may portend a wave of environmental emergencies;in that scenario, no world region has exhibited as much resilience as it would need © The Association for Asian Studies, Inc , 2020
Biological hydrogen production by anaerobic fermentation

Considering the energy security and the global environment, there is a pressing need to develop non-polluting and renewable energy sources. Alternatively, hydrogen is a clean energy carrier, producing water as its only by-product when it burns. Anaerobic bioconversion of organic wastes to hydrogen gas is an attractive option that not only stabilizes the waste/wastewater, but also generates a benign renewable energy carrier. The purposes of this study were to determine the kinetics of hydrogen production using different characteristics of substrates and to evaluate hydrogen production potential from different operating conditions in continuous operation. The growth kinetics of hydrogen-producing bacteria using three different substrates including sucrose, non-fat dry milk (NFDM), and food waste were investigated through a series of batch experiments. The results demonstrated that hydrogen production potential and hydrogen production rate increased with an increasing substrate concentration. The maximum hydrogen yields from sucrose, NFDM, and food waste were 234, 119, and 101 mL/g COD, respectively. The low pH (pH < 4) inhibited hydrogen production and resulted in lower carbohydrate fermentation at high substrate concentrations. The Michaelis-Menten equation was employed to model the hydrogen production rate at different substrate concentrations. The equation gave a good approximation of the maximum hydrogen production rate and the half saturation constant (KS) with correlation coefficient (R ) over 0.85. The values of half saturation constant (KS) for sucrose, NFDM, and food waste were 1.4, 6.6, and 8.7 g COD/L, respectively. Based on the Ks values, the substrate affinity of the enriched hydrogen-producing culture
Laser-Based Full Cut Dicing Evaluations for Thin Si wafers

Over the last years, singulation of thin semiconductor wafers with (ultra) low-K top layer has become a challenge in the production process of integrated circuits. The traditional blade dicing process is encountering serious yield issues. These issues can be addressed by applying a laser grooving process prior to the blade dicing, which is the process of reference nowadays. However, as wafers are becoming thinner, this process flow is not providing the yield and cost required. This paper will discuss the results of a study done on several multi beam laser ablation technologies on thin Si wafers and describe the pro's and con's for each of them.
The Impact of Digital Social legitimization on Website Visits and Web Sales

The present manuscript examines the role of digital social influence, as attained through Facebook, Instagram, Pinterest, Twitter, and YouTube, in attracting customers and achieving sales performance. The theoretical mechanism that serves as the basis for the study is social legitimacy theory. Specifically, the influence exerted by social media, and the resulting social legitimization of the marketer, are expected to drive both website visits and, ultimately, sales for the USA’s largest e-commerce retailers. The findings indicate that that all five manifest social media indicators converge into a single variable with significant loadings. This provides support for the multidimensional nature of the hypothesized digital social l egitimization construct. However, the structural equations analysis indicates that there is not a direct link between digital social l egitimization and Web sales performance. Nevertheless, digital social l egitimization does in fact positively impact website visits. In turn, these visits are associated with higher e-commerce sales.
Evaluation of Treatment Options for Ulcerative Dermatitis in the P Rat

Rotational outbred adult rats, phenotypically selected to prefer drinking alcohol ("P" rats) frequently present with selfinflicted wounds and ulcerative dermatitis, similar to that seen in C57BL/6 mice. Historically, veterinary interventions used to address this clinical condition have included triple antibiotic ointment (TABO), Columbia wound powder (CPW), nail trims, or plastic tubes that allow affected animals to hide. More recent studies have suggested that nail trims are the most successful intervention in mice, but this has not been evaluated previously in rats. In this study, we evaluated nail trims in rats and also tested whether placing a pumice stone in the cage would reduce the need for nail trims to reduce self-inflicted wounds. Our hypothesis was that interacting with the pumice stone would dull/trim the rats' nails without causing stress or illness and allow the wounds time to heal. We used 66 P rats that were assigned to 1 of 6 treatment groups (pumice stone, TABO, CWP, huts, nail trims, and an untreated control group) of 11 rats each. Rats were transferred to this study from a colony of experimentally naive animals that had evidence of dermatitis. The wounds were photographed and measured for 12 wk at 2 wk intervals. At the end of the study, representative skin samples from the site of the wound were collected for histopathologic evaluation of inflammation. Our data showed no significant differences in the inflammation scores. The rats treated with nail trims healed significantly more often than did all of the other treatment groups. This suggests that nail trims are the most effective intervention for treating self-inflicted wounds in P rats.
Institutional Postacute Care Use May Help Reduce Readmissions for Ischemic Stroke Patients.

Objectives Readmissions for Medicare patients initially admitted for stroke are common and costly. Rehabilitation in an institutional postacute care (PAC) setting is an evidence-based component of recovery for stroke. Under current Medicare payment reforms, care coordination across hospitals and PAC providers is key to improving quality and efficiency of care. We examined the causal impact of institutional PAC use on 30-day readmission rates for Medicare fee-for-service patients initially admitted for ischemic stroke. Data sources The 2010-2016 Medicare Provider Analysis and Review files. Research design We used the method of instrumental variable (IV) analysis to control for unobserved differences in the types of patients admitted to each PAC facility. We chose the distance from the patient's residence to the closest institutional PAC provider and the number of PAC providers of each type within a county where the patient resides as IVs. Principal findings In the naive model, an increase in institutional PAC use was significantly associated with an increase in 30-day readmission by 0.03 percentage points. However, using IV analysis to control for endogeneity bias, an increase in institutional PAC use was associated with a decrease in 30-day readmission rate by 0.19 percentage points. Our findings indicate that reducing institutional PAC use among patients typically requiring rehabilitation in institutional settings for recovery may potentially lead to adverse postdischarge outcomes that require rehospitalization. Thus, payment incentives to reduce institutional PAC use should be balanced with postdischarge outcomes among ischemic stroke patients.
What Is Emergent Vascular Access

Emergent vascular access represents a unique task that differs significantly from the kind of routine vascular access that is provided for patients presenting with a non-emergent condition. Providers who establish vascular access under emergent conditions deserve tailored guidance from experienced and credible authorities who understand how the effect of timing and disease acuity can and should influence decisions regarding the emergent placement of vascular access devices. This chapter describes some of the factors that may contribute to a determination of “emergent” vascular access.
On the Dynamics of Contributions and Beliefs in Repeated Public Good Games

I estimate a simultaneous equations model of contributions and beliefs in a repeated public good game, providing causal estimates of the effect of beliefs on contributions and the effect of contributions on beliefs, also known as the â€œprojection bias.â€
Designer Atomic Nuclei

New isotopes with unusual decay modes or number of neutrons are having impacts in areas ranging from astrophysics to medicine.
Hypopharyngeal pH monitoring artifact in detection of laryngopharyngeal reflux.

Hypopharyngeal pH artifacts have been a concern in the detection of laryngopharyngeal reflux. Our purpose was to analyze and quantify artifacts from dual-sensor hypopharyngeal pH monitoring. In all, 42 hypopharyngeal and 58 esophageal pH studies were reviewed. Type 1 (out of range), type 2 (pH drift), and type 3 (isolated pH drop) artifacts were identified. The proportion of proximal-sensor pH drop to <4 that was artifactual was determined. The median number (range) of artifacts was 1 (0–17) and 2 (0–28) for hypopharyngeal and esophageal pH studies, respectively (P = NS). The median proportion of artifactual pH drop to <4 was 1% (0–84%) and 2% (0–74%) for hypopharyngeal and esophageal pH studies, respectively (P = NS). The diagnosis did not change in any patient after excluding pH artifacts. In all, 19% of the combined 2432 hypopharyngeal pH drops of <4 were artifacts. In conclusion, hypopharyngeal pH artifacts per study were uncommon but can be prominent in a few patients. One can identify these artifacts and exclude them from analysis.
DNA Alterations in Human Aberrant Crypt Foci and Colon Cancers by Random Primed Polymerase Chain Reaction

Colon cancers are the result of the accumulation of multiple genetic alterations. To evaluate the role genomic instability plays during tumor development, we compared DNA fingerprints of 44 aberrant crypt foci (ACF; the earliest identified neoplastic lesion in the colon), 23 cancers, and normal crypts generated by random primers with PCR. The PCR products, separated by PAGE and viewed after silver staining, demonstrate altered fingerprints for 23.3% of the ACF and 95.7% of the cancers. In this first study of human ACF with this approach, the finding of altered DNA fingerprints in these microscopic lesions suggests that genomic instability can occur very early in human colon tumorigenesis.
Successful treatment of atypical sprue in an infant with cyclosporine

Cyclosporine was used to treat a child with severe, atypical sprue that was unresponsive to diet, parenteral nutrition, and corticosteroids. Therapy with cyclosporine resulted in a prompt clinical, functional, and histologic recovery. Remission was maintained for 1 yr until the drug was discontinued, when there was a histologic relapse that responded to reinstituting drug therapy. Cyclosporine may provide effective therapy for patients with similar disease.
METABOLIC CHARACTERIZATION OF THE GENUS BRUCELLA IV. 3: Correlation of Oxidative Metabolic Patterns and Susceptibility to Brucella Bacteriophage, Type abortus, Strain.

Meyer, Margaret E. (University of California, Davis). Metabolic characterization of the genus Brucella. IV. Correlation of oxidative metabolic patterns and susceptibility to Brucella bacteriophage, type abortus, strain 3. J. Bacteriol. 82:950–953. 1961.—A total of 212 strains of brucellae that had been identified as Brucella melitensis, B. abortus, B. suis, or B. neotomae by their oxidative metabolism were tested for their susceptibility to Brucella bacteriophage, type abortus, strain 3. It was demonstrated that only those organisms that displayed the oxidative metabolic pattern that is singular for B. abortus were susceptible to this strain of phage, irrespective of their identity by the conventional methods usually employed for differentiating members of this genus. Strains of organisms that display the features of B. melitensis by the conventional determinative methods, but display the metabolic characteristics of B. abortus, are susceptible to lysis by this phage. These organisms are in fact B. abortus. Strains of organisms that display the features of B. melitensis by the classical methods, and display the metabolic pattern of B. melitensis, are not lysed by this phage. These organisms are B. melitensis. The conclusions then were drawn that B. abortus is the only species that can serve as host for this strain of phage, that oxidative metabolic patterns accurately identify the species in this genus, and that by the conventional methods of differentiation, many strains of B. abortus are misidentified as B. melitensis.
Mechanical properties of cranial sutures.

Abstract Many bones in mammalian skulls are linked together by cranial sutures, connective tissue joints that are morphologically variable and show different levels of interdigitation among and within species. The goal of this investigation was to determine whether sections of skull with cranial sutures have different mechanical properties than adjacent sections without sutures, and if these properties are enhanced with increased interdigitation. To test these hypotheses, bending strength and impact energy absorption were measured for samples of goat (Capra hircus) cranial bone without sutures and with sutures of different degrees of interdigitation. Bending strength was measured under both dynamic (9.7 mm displacement s−1) and relatively static (0.8 mm s−1) conditions, and at either speed, increased sutural interdigitation provided increased strength during three-point bending. However, except for very highly interdigitated sutures loaded slowly, sutures were not as strong in bending as bone. In contrast, sutures absorbed from 16% to 100% more energy per unit volume during impact loading than did bone. This five-fold increase in energy absorption by the sutures was significantly correlated with increased sutural interdigitation.
Testing a model of science process skills acquisition: An interaction with parents' education, preferred language, gender, science attitude, cognitive development, academic ability, and biology knowledge

Path analysis techniques were used to test a hypothesized structural model of direct and indirect causal effects of student variables on science process skills. The model was tested twice using data collected at the beginning and end of the school year from 67 9th- and 10th-grade biology students who lived in a rural Franco-American community in New England. Each student variable was found to have significant effects, accounting for approximately 80% of the variance in science process skills achievement. Academic ability, biology knowledge, and language preference had significant direct effects. There were significant mediated effects by cognitive development, parents' education, and attitude toward science in school. The variables of cognitive development and academic ability had the greatest total effects on science process skills. Implications for practitioners and researchers are discussed.
The Anaphase-promoting Complex/Cyclosome Inhibitor Emi2 Is Essential for Meiotic but Not Mitotic Cell Cycles

Vertebrate oocytes awaiting fertilization are arrested at metaphase of meiosis II by cytostatic factor (CSF). This arrest is due to inhibition of the anaphase-promoting complex/cyclosome, in part by a newly identified protein, Emi2 (xErp1). Emi2 is required for maintenance of CSF arrest in egg extracts, but its function in CSF establishment in oocytes and the normal embryonic cell cycle is unknown. Here we show that during oocyte maturation, Emi2 appears only after metaphase I, and its level peaks at CSF arrest (metaphase II). In M phase, Emi2 undergoes a phosphorylation-dependent electrophoretic shift. Microinjection of antisense oligonucleotides against Emi2 into stage VI oocytes blocks progression through meiosis II and the establishment of CSF arrest. Recombinant Emi2 rescues CSF arrest in these oocytes and also causes CSF arrest in egg extracts and in blastomeres of two-cell embryos. Fertilization triggers rapid, complete degradation of Emi2, but it is resynthesized in the first embryonic cell cycle to reach levels 5-fold lower than during CSF arrest. However, depletion of the protein from cycling egg extracts does not prevent mitotic cell cycle progression. Thus, Emi2 plays an essential role in meiotic but not mitotic cell cycles.
Biologic Effects of Supernovae

Estimates of the probability that nearby explosions of supernovae have occurred during the earth's history and the biologic effects of the radiation therefrom are presented. They suggest that cosmic radiation from supernovae could have caused the extinction of many exposed animals without the simultaneous extinction of plant life. This suggests that supernovae should be considered as one possible mechanism by which fauna become extinct.
Differential Distribution of Amygdaloid Input across Rostral Solitary Nucleus Subdivisions in Rata

The orosensory nucleus of the solitary tract (NST) receives input from the amygdala, a key node in the forebrain feeding-related network. Despite numerous studies documenting the existence of this pathway, however, too little is known about the input organization to the gustatory brainstem to allow definitive conclusions about its functional role. Therefore, towards the long-term goal of characterizing such descending regulatory pathways, the purpose of the present study was to describe the distribution of input arising from the amygdala. The anterograde tracer, biotinylated dextran, was injected into the central amygdala based on stereotaxic coordinates in seven adult male rats. Following a 2-week survival time, the animals were sacrificed. Transverse sections of the brains were processed to visualize transported tracer and NST anatomical topography. Labeled fibers were differentially distributed among subdivisions throughout the rostrocaudal extent of NST. Within the rostral NST, the medial (M) subdivision had the highest density of terminal-like endings and swellings (30% of total density), followed by the ventral half of rostral central (vRC, 29%), ventral (V, 25%), dorsal half of rostral central (dRC, 12%) and rostral lateral (RL, 4%). In conclusion, it appears that amygdalar input preferentially overlaps with NST subdivisions (M, V, vRC) containing neurons with local efferent projections to the caudal NST and reticular nuclei that are implicated in medullary reflex circuits, rather than with subdivisions (dRC, RL) receiving primary orosensory afferent input and containing neurons having ascending efferent projections to the parabrachial nucleus. Thus, descending feeding-related pathways may be positioned to act as regulatory substrates controlling the output gain of brainstem circuits which may serve to modulate sensorimotor and autonomic reflexes in response to ingestive behaviors.
SU-GG-T-360: Monte Carlo-Based Pre-Installation Proton Therapy Shielding Verification for a Single-Room Proton Therapy Facility

Purpose: To validate analytic shielding and maze calculations prior to construction of a doorless in‐room accelerator proton therapy facility. Method and Materials: The MCNPXMonte Carlo program (version 2.6c) was used to model the treatment facility. LA 150 cross‐sections were used for all materials available. Maze walls, floors, and shielding walls, including all passage ways were included in the room geometry. Treatment losses were modeled with an Fe target placed at isocenter. The cyclotron was geometrically modeled with anticipated proton loss points. The cyclotron was modeled both with and without localized compound shielding. Simulations were performed for gantry angles of 0°, 90°, and 180° for the target source and 0°, 90°, and 135° for the cyclotron source. The 135° beam was simulated since it places the accelerator in a direct line‐of‐sight of an personnel access area in the lower level shielding wall. Neutron dose equivalent and photon dose values were tallied using mesh tallies throughout the treatment room, maze, and outside of the shielding enclosure and compared with design values. Neutron dose equivalent estimates used the ICRP‐74 neutron flux‐to‐dose rate conversion factors. Results:MCNPX simulations confirmed the analytical shielding estimates and indicated areas of under and over‐shielding in the facility plans. Beyond the shielding walls, photon dose equivalent values were less than 10% of the neutron values. Neutrons streaming from the accelerator through a lower maze shielding void contribute to the personnel dose to in the treatment control area. Use of 1″ of simple compound shielding reduces this contribution by a factor of 2.25. Conclusion:MCNPX is a valuable tool for pre‐installation verification of shielding design and indicate that doorless proton therapy vaults are feasible.
Development of a Tracer Fluid in a Vertical Tube With Gravity-Assisted and Resisted Motions

This study provides procedural tools that can be used in concert with a computer algorithm to simulate the two-phase flow development of a higher density, tracer fluid inside a vertical tube. The problem arises in the context of a tracer fluid (e.g., a contrast agent) being injected into a neutral fluid such as blood. Based on cell fractions of tracer fluid obtained numerically, absorbency profiles are extrapolated. These are shown to compare favorably with laboratory x-ray samples realized under similar flow conditions. At low Reynolds numbers, one finds that a downward profile exhibits a more elongated frontal boundary than predicted by laminar flow theory of a single-phase, Newtonian fluid. The observed stretching of the denser fluid is confirmed experimentally and can be attributed to the combined effects of gravity assistance near the core and viscous resistance near the wall. In gravity-resisted flow, a reverse behavior is observed. A blunter frontal boundary is established during upward motion. In both cases, the role of gravity is weakened with successive increases in the Reynolds number. This behavior suggests the existence of a Reynolds number above which gravitational bias can be neglected in any flow orientation. It is hoped that this study will set the pace for a broader investigation of two-phase motion characterization of a tracer fluid under various flow conditions and orientations.Copyright © 2007 by ASME
A major lysine tRNA with a CUU anticodon in insect mitochondria

We have sequenced a lysine tRNA from mosquito mitochondria that has the anticodon CUU. The preponderance of AAA lysine codons in insect mitochondrial genes, the parsimonious organization of the genomes, and the fact that this tRNA is a major component of the mosquito mitochondrial tRNA complement, lead us to suggest that the CUU anticodon recognizes AAC and AAA codons.
Pricing by geography: British journal pricing 1986, including developments in other countries

Abstract Since its first public forum in 1984, the issue of discriminatory pricing of British journals to the North American market has received considerable attention through discussions, articles, and a conference on “Learned Journal Pricing and Buying Round” which was held in London on March 22, 1985. Subsequently, some British publishers modified their pricing structure. As a follow-up to the authors' 1984 study, 1986 price lists of selected British publishers were examined to see what changes had occurred in the two years. In 1986 North American libraries were paying 39.3% more for their journals than domestic U.K. customers, and 18.5% more than “other overseas.” This is a drop of 45.3% and 49.2%, respectively, from 1984. The decreasing differential to the U.S. was partially offset by increased costs to other market segments. By comparing price lists for 1984 and 1986, it was determined that prices to the U.K. rose 21% between 1984 and 1986, “other overseas” by 17.3% and U.S. prices rose 9.4%. Market-based pricing, that is setting a differentiated price based on what the seller determines a market will pay, is still an active pricing mechanism for many British and now other foreign publishers such as VCH of West Germany. Marketing decisions such as prohibiting “buying round,” establishing exclusive distributorships in the United States, and differential pricing by geographic location all contribute to increased costs to U.S. and other North American libraries. United action by librarians forced a reduction in prices in German periodicals in 1933. The authors encourage librarians to make themselves heard and encourage publishers to establish fair and equitable prices for their journals worldwide.
Red cell substitutes: An update

The two acellular oxygen carriers currently being evaluated as red cell substitutes are hemoglobin solutions and fluorocarbon emulsions. We have shown that both products can maintain normal levels of oxygen consumption, CO 2 production, and circulatory dynamics in primates in the virtual absence of the red blood cell. Although each solution thus satisfies the most important criteria for a red cell substitute, development continues with both products. The clinical trials with the fluorocarbons have been discontinued due to the lack of efficacy of Fluosol-DA — 20% in the setting of acute blood loss. Our current hemoglobin preparation is a polymerized, pyridoxylated product that has a normal oxygen-carrying capacity. Clinical testing must await further evaluation of the safety and efficacy of this product. Alternative uses for both of these oxygen carriers continue to be explored, and may eventually be the area of their greatest utility in the clinical setting.
Editorial: Globalisation and women’s health in Sub-Saharan Africa:

This editorial discusses globalization the good and the bad aspects and focuses particularly on globalization in sub-Saharan Africa. It describes how Africa is performing poorly on the Millennium Development Goals (MDGs) and suffers greatly from globalization specifically women and their health in terms of food security.
The fractal dimension of policing

Abstract Crime is inherent in our society and the routine activities of everyday life ensure that circumstances will be created that will facilitate criminal behavior. The very nature of society—the need to go out and work and interact with others—initiates processes and situations that will encourage some people to be deviant and others to become victims. Criminal victimization is a deterministic part of our society but who will fall victim and who will become the offender remains uncertain. Crime, therefore, is characterized both by randomness and determinism, a situation that suggests the application of chaos theory for its study. This article argues that crime is a complex event that is the culmination of several processes emanating from the past. A method called R/S technique, based upon chaos theory, is used in an attempt to provide a different insight into the phenomenon of temporal crime data. This analysis uses an illustrative example to demonstrate that police calls for service data have a memory effect that can be identified by its fractal dimension. The technique suggests a new way to look at how the police system is functioning and raises questions about the situational factors.
The Effects of Site Conditions and Mitigation Practices on Success of Establishing the Valley Elderberry Longhorn Beetle and Its Host Plant, Blue Elderberry

This study performed the first systematic evaluation of the success of habitat mitigation at establishing the threatened Valley elderberry longhorn beetle (Desmocerus californicus dimorphus) and its host plant, blue elderberry (Sambucus mexicana). Habitat mitigation performed through enforcement of the U.S. Endangered Species Act represents a tightly controlled form of habitat restoration, facilitating the evaluation of restoration practice. Restoration plantings of blue elderberry have been substantial in our study area, the Central Valley of California. Surveys of 30 mitigation sites and 16 nearby natural sites showed that mitigation sites were a fraction of the size of natural habitat areas (mean = 24%) and contained smaller shrubs. The beetle colonized 53% of mitigation sites and its populations were denser in sites with moderate levels of dead stems on elderberry shrubs, and moderate damage to elderberry stems and bark. This likely indicates that the beetle responds to stressed shrubs, which are likely to contain elevated levels of nitrogen. Beetle density also increased with the size and age of mitigation sites. This indicates a need to make restoration sites as large as possible and to monitor these sites for longer than current guidelines suggest, thereby allowing more time for convergence of natural and mitigation sites. Few factors examined here directly influenced the growth of elderberry shrubs, but elderberry grew more rapidly in sites closer to riparian areas, indicating that such sites should be favored for mitigation sites.
Diffusion of Fluoride Through the Rat Enamel Organ in vitro

This study investigated the diffusion of fluoride through the enamel organ in vitro. The rat molar explants used were entirely in the secretory stage or predominantly in the maturation stage of enamel formation. The removal of the enamel organ or metabolic inhibition with iodoacetate caused significant increases in enamel fluoride uptake at both stages of enamel formation. Inhibition with dinitrophenol caused a significant increase only in the maturation phase. Uptake of fluoride in enamel was related to the fluoride concentration in the medium, except in the maturation stage explants, where increasing the medium fluoride concentration from 0.05 ppm to 0.08 ppm did not significantly increase fluoride uptake at any of the three observation times. The findings indicate that the enamel organ exists as a diffusion-limiting membrane to the movement of fluoride from the extracellular fluid compartment to the developing enamel.
First‐principles lattice dynamics and thermoelasticity of MgSiO3 ilmenite at high pressure

[1] Phonon dispersions of MgSiO3 ilmenite, a major mantle mineral, are calculated at high pressures by using first-principles density functional perturbation theory. Our results for the zone center modes and their initial pressure dependencies agree very well with the experimental Raman data. However, comparison with infrared data shows some discrepancy. The calculated eigenvectors indicate that low-frequency modes are primarily associated with the stretching of weak Mg-O bonds, whereas high-frequency modes are dominated by the stretching of stiff Si-O bonds. All the mode frequencies are shown to increase monotonically with increasing pressure and no soft modes exist over the pressure regime studied (� 11 to 33 GPa). Several thermodynamic properties including the thermal equation of state, thermal expansivity, entropy, and heat capacity that can be useful to better understand the contribution of the silicate ilmenite phase to the composition and dynamics of the Earth’s mantle are successfully presented at geophysically relevant pressure-temperature conditions. INDEX TERMS: 3924 Mineral Physics: High-pressure behavior; 3929 Mineral Physics: NMR, Mossbauer spectroscopy, and other magnetic techniques; 3949 Mineral Physics: Thermal expansivity; 3655 Mineralogy and Petrology: Major element composition; 3939 Mineral Physics: Physical thermodynamics; KEYWORDS: MgSiO3 ilmenite, first-principles study, lattice dynamics, thermoelasticity, high pressure, Earth’s mantle
Compensatory growth response of the legume, Medicago sativa, to defoliation and denodulation

A laboratory study was conducted to determine the effects of defoliation and denodulation on compensatory growth of Medicago sativa (L.). Plants grown hydroponically in clear plastic growth pouches were subjected to 0 and 50% nodule pruning, and 0, 25, 50, and 75% defoliation by clipping trifoliate leaves. An additional experiment was conducted to determine if clipping leaves simulated herbivory by Hypera postica (Gyllenhal) larvae. Previously, we determined that nodule pruning accurately simulated herbivory by Sitona hispidulus (L.) larvae (Quinn & Hall, 1992). Results indicated that denodulation stimulated nodule growth and caused exact compensation in standing and total number of nodules per plant within 15 days and in standing nodule biomass within 22 days of treatment. Denodulation caused a significant reduction (13%) in final shoot biomass, but did not affect significantly final root biomass. Percentage of change in number of trifoliate leaves per plant increased with the level of defoliation. Within 22 days of treatment, total number of trifoliate leaves per plant was similar to controls. However, final standing shoot biomasses were significantly less that controls, indicating undercompensatory growth. Shoot biomasses of the 25-, 50-, and 75%-defoliated plants were 18, 20, and 36% lower than controls, respectively. Nodule biomass per plant was reduced by 24 and 32% in 50- and 75%-defoliated plants, respectively, but was not affected significantly by 25% defoliation. Root biomass was affected by all levels of defoliation. Clipping trifoliate leaves accurately simulated defoliation by H. postica larvae. Our results indicated that partial defoliation affected shoot, root, and nodule biomass of M. sativa, but that partial denodulation only affected shoot biomass.
Comparison of the use of zeolite and perlite as substrate for crisp-head lettuce

This research was carried out to assess the effects of zeolite and perlite on growth and nutrient status of lettuce plants and the amount of waste elements. The trials were done in a PE covered tunnel during autumn and spring seasons. Plant material was Lactuca sativa var. capitata, and the cultivars Bombola and Brogan were used for autumn and spring seasons, respectively. Five different growing media based on perlite and clinoptilolite, a kind of zeolite, mixed at different ratios (1 + 0, 3 + 1, 1 + 1, 1 + 3, 0 + 1, v/v) were tested. It was concluded that the use of zeolite led to increased plant growth, higher N and K contents in plant tissues and to reduced K leaching.
Effect of additives, catalyst residues, and confining substrates on the fractionated crystallization of polypropylene droplets

Fractionated crystallization of Ziegler-Natta PP (ZN-PP) droplets produced from ZN-PP/polystyrene (PS) multilayered films resulted in four crystallization exotherms at 40, 64, 90, and 103°C. The origins of these crystallization peaks were investigated in this article. The nucleation of ZN-PP droplets at various crystallization exotherms was attributed to (1) various additives in ZN-PP and PS, (2) catalyst residues present in ZN-PP, or (3) substrate nucleation by confining matrix. Effect of various additives on the fractionated crystallization an additive-free grade of ZN-PP (cPP) was investigated. Crystallization of cPP droplets from 200-nm layers showed that Irganox was responsible for crystallization of droplets at 103°C. Irgafos and ZnS did not affect the crystallization of cPP droplets. We also investigated three grades of PP, which were synthesized using different catalysts. The PP grades were ZN-PP, developmental PP (D-PP) and metallocene PP (M-PP). D-PP droplets from 200-nm layers showed crystallization at 100°C, while ZN-PP resulted in crystallization at 90 and 103°C. It was suggested that the 90°C peak for ZN-PP droplets was most likely due to the presence of Ziegler-Natta catalyst residues. Crystallization of M-PP droplets produced from 200 nm showed multiple crystallization exotherms (60 to 90°C). The effect of confining substrates on the fractionated crystallization of ZN-PP droplets revealed heterogeneous nucleation by polycarbonate (PC) substrate. When the confining matrix was changed from polystyrene (PS) to polymethyl methacrylate (PMMA), the crystallization thermograms of ZN-PP droplets were unaffected. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Gravitational stability of scalar matter

Abstract The question of the stability of matter against gravitational collapse is of general interest to astrophysics. In this work we investigate the stability against small radial oscillations of equilibrium configurations of cold, gravitationally bound states of complex scalar fields, known as boson stars. These equilibrium configurations exhibit a mass profile against central density which is very similar to that of ordinary neutron stars, with a pronounced maximum mass at Mc = 0.633MPl2/m, where MPl is the Planck mass, for a certain value of the central density σc(0). We give analytical and numerical proof that configurations with central densities greater than σc(0) are unstable against radial perturbations by studying the behavior of the eigenfrequencies of the perturbations for different values of σ(0).