cssi/SciSciGPT-SciSciNet huggingface dataset:
Powdery Mildew on Watermelon in Florida

This 3-page document discusses the symptoms and management of powdery mildew, a problematic fungal disease, on watermelon in Florida. Written by Pamela D. Roberts, Mathews Paret, and Nicholas Dufault and published by the UF/IFAS Plant Pathology Department, January 2019. http://edis.ifas.ufl.edu/pp342
Surviving and Thriving as Physicians in General Internal Medicine Fellowship in the Twenty-First Century.

General internal medicine (GIM) fellowships play an important role in the development of physician scientists and clinical educators, as well as leaders in academic medicine. Nevertheless, the challenges of developing another novel aspect to one’s career, along with balancing coursework, research productivity, clinical duties, and personal life during fellowship, can be overwhelming. Similarly, successfully securing a job at the end of fellowship can be a daunting process. In this article, we discuss the foundational tenets and themes of the GIM fellowship. These themes include (1) finding your purpose and passion, with a focus on selecting research coursework and developing an area of study; (2) the role and importance of mentorship, including the various kinds of mentorship that fellows require (traditional and peer mentorship, sponsors, and coaches), as well as how to be an effective mentee; (3) securing research funding; (4) landing a job; (5) and protecting time to meet personal goals. There is an increased need for a vibrant, diverse, and successful generation of general internal medicine researchers to advance our understanding of complex issues in clinical medicine and healthcare delivery and to inform health policy. It is our hope that this piece helps to support that mission.
Wind Resistance and Fragility Functions for Wood-Framed Wall Sheathing Panels in Low-Rise Residential Construction

AbstractThe wind uplift resistance of wood roof sheathing panels has been the subject of many engineering studies due to the high probability that roofs are subjected to large uplift loads during i...
Acromial morphology is not associated with rotator cuff tearing or repair healing.

Background The purposes of this study were to determine whether acromial morphology (1) could be measured accurately on magnetic resonance images (MRIs) as compared to computed tomographs (CTs) as a gold standard, (2) could be measured reliably on MRIs, (3) differed between patients with rotator cuff tears (RCTs) and those without evidence of RCTs or glenohumeral osteoarthritis, and (4) differed between patients with rotator cuff repairs (RCRs) that healed and those that did not. Methods This is a retrospective comparative study. We measured coronal, axial, and sagittal acromial tilt; acromial width, acromial anterior and posterior coverage, and glenoid version and inclination on MRI corrected into the plane of the glenoid. We determined accuracy by comparison with CT via intraclass correlation coefficients (ICCs). To determine reliability, these same measurements were made on MRI by 2 observers and ICCs calculated. We compared these measurements between patients with a full-thickness RCT and patients aged >50 years without evidence of an RCT or glenohumeral osteoarthritis. We then compared these measurements between those patients with healed RCRs and those with a retorn rotator cuff on MRI. In this portion, we only included patients with both a preoperative MRI and a postoperative MRI at least 1 year from RCR. Only those patients without tendon defects on postoperative MRIs were considered to be healed. In these patients, we also radiographically measured the critical shoulder angle. Results In a validation cohort of 30 patients with MRI and CT, all ICCs were greater than 0.86. In these patients, the inter-rater ICCs of the MRI measurements were >0.53. In our RCT group of 110 patients, there was greater acromial width [mean difference (95% confidence interval) = 0.1 (0, 0.2) mm, P = .012] and significantly less sagittal acromial tilt [9° (5°-12°), P Conclusion Although the acromion is wider in RCTs, the difference of 0.1 mm likely has no clinical significance. The acromion is more steeply sloped from posteroinferior to anterosuperior in those with RCTs. These findings call into question subacromial impingement due to native acromial morphology as a cause of rotator cuff tearing. Acromial morphology, critical shoulder angle, and glenoid inclination were not associated with healing after RCR. This study does not support lateral acromioplasty.
Establishment of reference values for analysis of thyroid function in school-age children in iodine-adequate nutrition areas

Objective To establish reference values for thyroid hormone in school-age children in iodine-adequate nutrition areas. Methods Totally 128 8 - 10-year-old healthy children (male: 62, female: 66) were screened rigorously in iodine-adequate nutrition areas (median of urinary iodine: 100 - 200 μg/L). The values of total triiodothyronine (TT3), total thyroxine (TT4), free triiodothyronine (FT3), free thyroxine (FT4), thyrotropin (TSH), thyroglobulin (Tg), thyroid peroxidase antibody (TPOAb), and thyroglobulin antibody (TgA) in serum were determined through the Access 2 Immunoassay System (Beckman-Coulter, USA) using a chemiluminescence detection system. Results Normal reference ranges for thyroid function indicators in children (95% confidence limit) of TT3, TT4, FT3, FT4, TSH, and Tg were 1.63 - 3.36 nmol/L, 110.65 - 186.67 nmol/L, 4.65 - 7.25 pmol/L, 9.75 - 15.59 pmol/L, 1.10 - 5.54 mU/L, and 3.75 - 36.27 μg/L, respectively. There was no significant difference in hormone levels between boys and girls (P > 0.05). The thyroid function indices were substantially different between children and adults. Conclusions Normal reference range of thyroid function index of children is different from that of adults. It is necessary to establish the reference range of thyroid function indices for children in order to diagnose thyroid diseases and monitor iodine nutrition. Key words: Child; Thyroid hormone; Reference value
Reduction in Formation Temperature of Ta-Doped Lithium Lanthanum Zirconate by Application of Lux-Flood Basic Molten Salt Synthesis

Garnets such as Li7La3Zr2O12 (LLZO) are important Li+ conducting ceramics for potential use as solid electrolytes in solid-state batteries. However, LLZO is predominately prepared by using solid-st...
Hip Arthroscopy in the High-Level Athlete: Does Capsular Closure Make a Difference?

Background:Hip arthroscopy has been shown to be effective in athletes who have femoral acetabular impingement and labral tearing. The effect of complete capsular closure versus nonclosure on return...
Ovoid Foramen Magnum Shape is Associated with Increased Complications and Decreased Extent of Resection for Anterolateral Foramen Magnum Meningiomas.

Background Antero-laterally located meningiomas of the foramen magnum (FM) pose significant surgical resection challenges. The effect of FM shape on surgical resection of FM meningiomas has not been previously studied. The present study investigates how FM shape effects the extent of tumor resection and complication rates in antero-lateral FM meningiomas. Materials and Methods This retrospective study included 16 consecutive patients with antero-lateral FM meningiomas operated on by a single surgeon. FMs were classified as ovoid (n = 8) and nonovoid (n = 8) using radiographic evaluation. Results Sixteen patients were examined: seven males and nine females (mean age of 58.5, and range of 29 to 81 years). Gross total resection was achieved in 81% of patients, with tumor encased vertebral arteries in 44%. Patient characteristics were similar including age, sex, preoperative tumor volume, relationship of vertebral artery with tumor, preoperative Karnofsky performance score (KPS), symptom duration, and presence of lower cranial nerve symptoms. The ovoid FM group had lower volumetric extents of resection without statistical significance (93 ± 10 vs. 100 ± 0%, p = 0.069), more intraoperative blood loss (319 ± 75 vs. 219 ± 75 mL, p = 0.019), more complications per patient (1.9 ± 1.8 vs. 0.3 ± 0.4, p = 0.039), and poorer postoperative KPS (80 ± 21 vs. 96 ± 5, p = 0.007). Hypoglossal nerve palsy was more frequent in the ovoid FM group (38 vs. 13%). Conclusion This is the first study demonstrating that ovoid FMs may pose surgical challenges, poorer operative outcomes, and lower rates of extent of resection. Preoperative radiological investigation including morphometric FM measurement to determine if FMs are ovoid or nonovoid can improve surgical planning and complication avoidance.
Characteristics and Reporting of Number Needed to Treat, Number Needed to Harm, and Absolute Risk Reduction in Controlled Clinical Trials, 2001-2019.

This cross-sectional study assesses the trends and characteristics of absolute measure reporting in highly cited medical journals from 2001 to 2019.
Phosphorylation state-dependent interaction between AKAP7δ/γ and phospholamban increases phospholamban phosphorylation.

Abstract Changes in heart rate and contractility in response to sympathetic stimulation occur via activation of cAMP dependent protein kinase A (PKA), leading to phosphorylation of numerous substrates that alter Ca 2 + cycling. Phosphorylation of these substrates is coordinated by A-kinase anchoring proteins (AKAPs), which recruit PKA to specific substrates [1]. Phosphorylation of the PKA substrate phospholamban (PLB) is a critical determinant of Ca 2 + re-entry into the sarcoplasmic reticulum and is coordinated by AKAP7δ/γ [2,3]. Here, we further these findings by showing that phosphorylation of PLB requires interaction with AKAP7δ/γ and that this interaction occurs only when PLB is unphosphorylated. Additionally, we find that two mutants of PLB (R9C and Δ14), which are associated with dilated cardiomyopathy in humans, prevent association with AKAP7δ/γ and display reduced phosphorylation in vitro. This finding implicates the AKAP7δ/γ–PLB interaction in the pathology of the disease phenotype. Further exploration of the AKAP7δ/γ–PLB association demonstrated a phosphorylation state-dependence of the interaction. Computational modeling revealed that this mode of interaction allows for small amounts of AKAP and PKA (100–200 nM) to regulate the phosphorylation of large quantities of PLB (50 μM). Our results confirm that AKAP7γ/δ binding to PLB is important for phosphorylation of PLB, and describe a novel phosphorylation state-dependent binding mechanism that explains how phosphorylation of highly abundant PKA substrates can be regulated by AKAPs present at ~ 100–200 fold lower concentrations.
Bounding uncertainty in functional data: A case study

Functional data are fast becoming a preeminent source of information across a wide range of industries. A particularly challenging aspect of functional data is bounding uncertainty. In this unique ...
Notes of a protein crystallographer: the legacy of J.-B. J. Fourier - crystallography, time and beyond

The importance of the Fourier transform as a fundamental tool for crystallo­graphy is well known in the field. However, the complete legacy of Jean-Baptiste Joseph Fourier (1768–1830) as a pioneer Egyptologist and premier mathematician and physicist of his time, and the implications of his work in other scientific fields, is less well known. Significantly, his theoretical and experimental work on phenomena related to the transmission of heat founded the mathematical study of irreversible phenomena and introduced the flow of time in physico-chemical processes and geology, with its implications for biological evolution. Fourier's insights are discussed in contrast to the prevalent notion of reversible dynamic time in the early 20th century, which was dominated by Albert Einstein's (1875–1953) theory of general relativity versus the philosophical notion of duree proposed by the French philosopher Henri-Louis Bergson (1859–1941). The current status of the mathematical description of irreversible processes by Ilya Romanovich Prigogine (1917–2003) is briefly discussed as part of the enduring legacy of the pioneering work of J.-B. J. Fourier, first established nearly two centuries ago, in numerous scientific endeavors.
Out of Distribution Detection for Medical Images

Neural network architectures behave in unpredictable ways when testing on inputs which do not resemble their training data. It is valuable to detect any out-of-distribution (OOD) inputs to make any overseers aware of the limitations of the model’s output. To address this need, a large number of methods for detecting OOD inputs have been proposed and tested on small datasets such as CIFAR10, SVHN, or LSUN. The purpose of this study is to determine the effectiveness of different methods for OOD detection on the domain of medical images. We investigate three common OOD detection methods (Maximum Softmax Probability, Confidence Branch, and Outlier Exposure) and report their effectiveness on widely used medical image datasets. We find that OOD detection metrics are volatile and can have large changes in performance in a short amount of training steps. Moreover, we also observe that OOD detection is sensitive to the choice of hyperparameters. Our code is reproducible at this link (https://github.com/oliverzhang42/ood_medical_images).
Food Insecurity in Toddlerhood and School Readiness: Mediating Pathways Through Parental Well-Being and Behaviors

Food insecurity in the United States is both widespread among families with children—currently affecting nearly one in three families—and especially damaging during early childhood, in part because of its links to children’s language, mathematics, and socio-emotional skills at school entry. In order to alleviate this problem, it is imperative to know how food insecurity impacts development, yet little research has looked at this question. Using nationally representative data, we explore whether a broad set of parent well-being and behavioral factors serve as links between food insecurity in toddlerhood and skills at kindergarten entry. We find that the relationship between food insecurity and development is mediated by parent depression and stress, but not by the use of cognitively stimulating activities at home or by observed parenting behaviors. This suggests that efforts to reduce the impact of food insecurity on children should also prioritize parental well-being. Policy implications are discussed.
Abstract 14990: Sudden Death in Patients with Heart Failure and Preserved Ejection Fraction

Introduction: Severely reduced left ventricular ejection fraction (EF) is an established risk factor for sudden cardiac death (SCD), but has limited sensitivity and specificity. We evaluated the contribution of heart failure (HF) with preserved ejection fraction toward risk of SCD in the general population. Hypothesis: We hypothesized that HF would predict risk of SCD, even among patients with preserved EF. Methods: Subjects from an ongoing community-based study of SCD in the northwest US (pop. approx. one million) were included if age ≥18 (2002 - 2012) with clinical history and assessment of EF. Clinical history of heart failure (HF) was determined by physician report. Ejection fraction (EF) was determined from echocardiogram, angiogram, or multigated acquisition scan, and categorized as EF <20%, 20-34%, 35-44%, 45-54%, and ≥55%. Laboratory values of brain natriuretic peptide (BNP) were obtained from routine clinical laboratory testing for a subset of patients. Results: Cases (n=628, mean age 69.9, 65% male) were more likely than controls (n = 580, mean age 66.8, 66% male) to have a history of clinically-recognized HF (58% vs. 24%, p<0.0001) and to have an EF ≤ 35% (27% vs. 12%, p<0.0001). At each EF level above 20%, HF was approximately twice as prevalent in cases compared to controls (Figure, p≤0.002). Median BNP levels were significantly higher for patients with HF vs. those without, across EF categories. Adjusting for age and sex, each category of decreasing EF was associated with an increased risk of SCD (OR 1.4, 95% CI 1.3 - 1.6, p<0.0001), but the association was diminished by adjustment for HF, and for BNP. Odds of SCD were 4-fold higher (p<0.0001) in the presence HF, adjusting for age and sex, across all categories of EF. Conclusions: In this population, the significant role of HF with preserved EF in SCD was confirmed by BNP level trends. Improvements in SCD prevention will require focused investigation of high risk SCD markers in patients with heart failure and preserved EF. ![][1] [1]: /embed/graphic-1.gif
English as a plural language: The significance of Yamuna Kachru

In a distinguished career spanning five decades Professor Yamuna Kachru enriched several areas of linguistics and applied language studies. This initial appreciation attempts to show how her family background, education, and experience on three continents shaped her interests and perspectives. The evolution of her research is structured as a series of concentric circles, each informed by the previous ones. The inner circle is her monumental work on Hindi grammar and sociolinguistics. The second circle concerns contrastive analysis, second language acquisition and teaching, and multilingualism. The third circle involves pragmatics, discourse structure, and world Englishes. The salient features of her scholarship are outlined, along with her vital role in bringing about world-wide recognition of the new paradigm of world Englishes through original research, teaching, and building the academic infrastructure for the field through texts, reference works, the journal World Englishes, and the professional society IAWE.
Immobilization of protein molecules on liposomes: Anchorage by artificially bound unsaturated hydrocarbon tails

A method for the immobilization of trypsin, a hydrophilic nonmembrane protein, on a liposomal surface has been developed. The technique consists of covalent coupling of linoleoyl residues to the protein globules and consequent binding of linoleoyl trypsin to liposomes by a detergent dilution method. The immobilized protein preserved its biological functions: specific esterolytic catalytic activity and ability to bind to a macromolecular trypsin protein inhibitor. Liposomes carrying immobilized trypsin were able to sequester glucose with the same efficiency as liposomes without trypsin.
On the Incorporation of Time-delay Regularization into Curvature-based Diffusion

A new anisotropic nonlinear diffusion model incorporating time-delay regularization into curvature-based diffusion is proposed for image restoration and edge detection. A detailed mathematical analysis of the proposed model in the form of the proof of existence, uniqueness and stability of the “viscosity” solution of the model is presented. Furthermore, implementation issues and computational methods for the proposed model are also discussed in detail. The results obtained from testing our denoising and edge detection algorithm on several synthetic and real images showed the effectiveness of the proposed model in prserving sharp edges and fine structures while removing noise.
Hemolytic Plaque-Forming Cells and Antigen-Sensitive Units in Spleens of Germfree and Conventional Mice

Immunocytes producing so-called natural antibodies are not detected in the spleens of germfree, colostrum-deprived animals reared on diets lacking bacterial and other antigens (1). Upon exposure of such animals to sheep erythrocytes, potentially immunocompetent cells generate, by proliferation and differentiation, antibody-forming cells. The number of antibody-forming cells increases with the animal’s age, but is not influenced by pretreat-ments with nonspecific stimulants of the lymphoid or reticuloendothelial system (1). It seems that antigen is not necessary for the differentiation of the primitive lymphoid cells not producing antibody, but capable of interacting with antigens and of initiating an immune response. The role of antigen is to trigger these primitive cells, called antigen-sensitive units (2) into the path of differentiation leading to mature lymphoid cells synthesizing a specific immunoglobulin.
Geometry, Algebra, and Algorithms

This chapter will introduce some of the basic themes of the book. The geometry we are interested in concerns affine varieties, which are curves and surfaces (and higher dimensional objects) defined by polynomial equations. To understand affine varieties, we will need some algebra, and in particular, we will need to study ideals in the polynomial ring k[x1, …, xn]. Finally, we will discuss polynomials in one variable to illustrate the role played by algorithms.
Observations of projectile penetration into a transparent soil

Abstract In this study, a transparent sand surrogate was employed along with high-speed imagery to un-intrusively visualize the penetration of a spherical projectile into the center of a saturated granular target, representing angular sand, at speeds ranging between 60 and 150 m/s. The transparent sand was made by saturating an angular granular fused quartz waste product with a matched refractive index pore fluid made of sucrose. A distinct zone of opacity was observed traveling ahead of the projectile. The opacity zone appears circular during initial penetration and transitions into the shape of an elongated cone in shots with higher initial velocities. Some healing was also observed with time and some increase in transparency was observed. Some of the opacity is attributed to dilatancy of the granular fused quartz during penetration, and healing is attributed to flow of pore fluid into the dilated zone.
Density-Dependent Oviposition by Female Aedes albopictus (Diptera: Culicidae) Spreads Eggs Among Containers During the Summer but Accumulates Them in the Fall

When possible, oviparous females should deposit eggs in sites that maximize the future performance of their offspring. Therefore, studies of oviposition behavior may uncover parameters important to offspring fitness. Gravid female Aedes albopictus (Skuse) were given a choice of containers with leaf infusion or plain water, either open or with a cover with a small opening, and their behavior was compared under summer (long day, higher temperature) or fall (short day, lower temperature) regimes. Open containers with leaf infusion were always preferred, but over time, summer females expanded their choices to oviposit in all containers and follow-up experiments indicated that the number of eggs laid was inversely correlated to the number of eggs present. In contrast, fall females laying diapausing eggs that do not hatch until the spring, accumulated eggs in open containers with food resulting in high egg densities. Combined, these results demonstrate a seasonal shift that suggests either high winter egg mortality or safety in numbers. It also demonstrates that female Ae. albopictus change their behavior based on cues associated with expected added risk, which varies across time and space. The wide distribution of summer eggs across container types may contribute to the fast expansion of Ae. albopictus across its invasive range, but egg accumulation in the fall may be exploited for control.
Association of high dietary saturated fat intake and uncontrolled diabetes with constipation: evidence from the National Health and Nutrition Examination Survey.

Background Constipation is highly prevalent in the United States. The association of dietary fat intake with constipation has not been well studied. We recently reported that mice fed a high-fat diet had higher incidence of constipation than regular diet fed mice. The aim of this study was to assess if increased intake of dietary saturated fat in humans is also associated with higher risk of constipation and reduced stool frequency. Methods Analyses were based on data from 6207 adults (≥20 years) from the 2005–2006 and 2007–2008 cycles of the National Health and Nutrition Examination Surveys who had completed the bowel health questionnaire. Constipation was defined as a stool frequency of less than three times per week. Multivariable logistic regression analysis was used to calculate adjusted prevalence odds ratio (OR) estimates. Statistical analyses were performed using R and RStudio softwares. Key Results The prevalence of constipation in this sample was 3.1%. After multivariable adjustment high saturated fat remained associated with constipation. The OR for high saturated fat intake associated with constipation was much higher in diabetics above 65 years, especially in non-Hispanic blacks, females, and those with poor glycemic control, compared to the control group. Conclusions & Inferences To the best of our knowledge, this is the first report to investigate the association of high saturated fat diet, bowel frequency, and diabetes. This study demonstrates that a high dietary saturated fat intake is associated with significant increase in the prevalence of constipation, especially in the uncontrolled diabetic, non-Hispanic black, female patients.
Sydenham chorea: MR manifestations in two cases.

The acute onset of a unilateral choreiform movement dis­ order in a child with a recently documented febrile illness or streptococcal pharyngitis is suggestive of Sydenham chorea. The MR manifestations of two clinically corroborated cases of Sydenham chorea are summarized. Increased signal inten­ sity in the corpus striatum contralateral to the patients' symp­ tomatic side was observed on T2-weighted images. Focal enhancement in the involved head of the caudate was iden­ tified after IV administration of gadopentetate dimeglumine. The MR findings correlated with anatomic regions , which have been described to be susceptible to cross reaction with lgG antibodies that are formed in association with streptococcal infection.
Iron Cofactors: Nonhaem

Proteins and enzymes with nonhaem iron centres display many functions: metal centres with primarily sulfur ligation are involved in electron transfer, electrophilic activation of hydroxyl groups, fixation of N2 and regulation of gene expression; mononuclear and diiron centres with oxygen and nitrogen ligation have roles in various reactions with O2 and in hydrolysis. The principles of their mechanisms of action have emerged from considerable experimentation. Ongoing research is refining understanding of their mechanisms of action and attempting to test and extend their already substantial catalytic capabilities. Key Concepts Nonhaem iron-containing enzymes carry out a myriad of catalytic reactions. Iron–sulfur centres participate in electron transfer, electrophilic catalysis, nitrogenase and hydrogenase reactions. Mononuclear and diiron monooxygenases, dioxygenases and oxidases provide nonhaem counterparts to catalysis carried out by haem-containing enzymes. Rearrangements of protein ligands in nonhaem iron active sites provide a unique aspect to control catalysis. Nonhaem oxidative enzymes access high-valent states of iron during catalysis. The electrophilic nature of nonhaem iron also supports effective hydrolytic catalysis in reactions where O2 activation is not required. Keywords: iron; enzyme mechanism; enzyme structure; enzyme specificity; metalloproteins; iron–sulfur clusters; nitrogenase; hydrogenase; S-adenosylmethionine; radical SAM; hydrogenase; monooxygenase; dioxygenase; lipoxygenase; transferrin; diiron; haemerythrin; ferritin; ribonucleotide reductase; desaturase
The use of a digital computer in d.c. arc spectrographic analysis

Abstract A program used with an I.B.M. 1620 computer, is described which performs most of the routine calculations involved in spectrographic analysis. The program includes an emulsion calibration, background corrections, internal standard ratio calculations, arc temperature and electron pressure determinations, and corrections for matrix effects.
MAKING FAIR AND PREDICTABLE SALARY ADJUSTMENTS FOR FACULTY OF PUBLIC RESEARCH UNIVERSITIES

Building upon earlier work by Camp, Gibbs, and Masters II, (1988). The Journal of Higher Education 59(6): 652–667 and Wenger and Girard, (2000). Research in Higher Education 41(2):195–207, we present a model for allocating funds for salary increases to faculty lines within an academic unit at a public research university. The model first divides available funds into three separate amounts, based on the unit norms adopted by the faculty of the academic unit. These norms define the relative effort levels to be placed on teaching, scholarship, and service. The model enables individual faculty members to negotiate different effort levels for the respective activities. Within each of these activities, specific weights can be assigned to different types of accomplishments. The result is a flexible approach that allows fair and predictable salary increases to be assigned on the basis of criteria that have been agreed to by the faculty of the academic unit.
Alcohol and hamster buccal pouch carcinogenesis.

Abstract Alcohol was shown enhance the carcinogenic effect of DMBA applied to hamster buccal pouch. DMBA animals given alcohol developed dysplastic leukoplakic lesions and epidermoid carcinomas 2 weeks ahead of water-drinking control animals. The tumors also grew to larger size, were more invasive, and were more anaplastic histologically. Forty young adult Syrian hamsters were divided into four groups (alcohol-DMBA, DMBA control, untreated control, and alcohol control) and were killed after 10, 12, and 14 weeks of DMBA applications three times weekly. Alcohol was given as a 10 percent solution instead of drinking water.
Characterization of the RF ablation-induced 'oven effect': the importance of background tissue thermal conductivity on tissue heating.

Purpose: To determine the effect of background tissue thermal conductivity on RF ablation heating using ex vivo agar phantoms and computer modelling.Method: Two-compartment cylindrical agar phantom models (5% agar, 5% NaCl, 3% sucrose) were constructed. These included a standardized inner compartment (2 cm diameter, 4 cm length, 0.25% agar) representing a tumour, surrounded by an outer compartment representing background tissue. The thermal conductivity of the outer compartment was varied from 0.48 W m−1°C (normal liver) to 0.23 W m−1°C (fat) by adding a fat-saturated oil-based solute (10–90%) to the agar. RF ablation was applied at 2000 mA current for 2 min. Temperatures were recorded up to 4 cm from the electrode tip at 1 cm intervals. Subsequently, a 2-D finite element computer model was used to simulate RF ablation of 2–24 min duration for tumours measuring 2–4 cm in diameter surrounded by tissues of different thermal conductivity with the presence or absence of perfusion (0–5 kg m−3 s−1) (n = 44). A ...
Septo-hippocampal drug interactions in post-trial memory processing

Abstract To determine if serotonin and GABA regulate post-trial memory processing of the cholinergic projection from the septum to the hippocampus, mice were trained on footshock avoidance in a T-maze. Immediately after training, drugs were injected into the septum, hippocampus or both. Retention was tested 1 week after training and drug administration. Ketanserin, a serotonin type 2 receptor antagonist at a dose of 0.5 ng, had no measurable effect on retention, but it reduced the dose of bicuculline, in the septum, or arecoline in the hippocampus that was needed to improve retention. DOI, a serotonin type 2 receptor agonist at a dose of 2.5 ng, had the opposite effect of increasing the doses of bicuculline and arecoline needed to improve retention. Bicuculline, a GABAA receptor antagonist at a dose of 0.1 pg, did not affect retention when injected alone into the septum, but it reduced the dose of arecoline needed to improve retention in the hippocampus. Muscimol, a GABAA receptor agonist at a dose of 5 ng, injected into the septum, increased the dose of arecoline needed to improve retention. The results of this study are compatible with models that propose that serotonin innervation from the median raphe drives GABA interneurons in the medial septum that synapse on cholinergic neurons projecting to the hippocampus.
Volatility in the terms of trade with non-identical preferences

Abstract This paper studies the terms of trade volatility in a two-country two-commodity general equilibrium pure exchange model with state-dependent endowments, allowing non-identical preferences across countries. We find that the introduction of a forward market may result in a higher terms of trade volatility with non-identical preferences, while it is independent of market completeness with identical preferences. We also find that, when markets are complete, non-identical preferences lead to more volatile terms of trade, compared with the identical preference case, if and only if the product of the coefficients of relative risk aversion and the elasticities of substitution is greater than one. (JEL F31).
Treating the patient with a cardiovascular disease

The symptoms of cardiovascular disease and the proper drugs used in treatment of emergencies are described.
On logarithmic extrapolation of microbial survivor curves for planetary quarantine requirements.

A number of scientists active in planetary quarantine have questioned the logarithmic extrapolation of microbial survivor curves over non-measurable ranges to obtain thermal sterilization cycles for spacecraft applications (DAvIEs and HOROWITZ, 1966; GEmER et al., 1965; JAFFE, 1963). If observed non-logarithmic survival is the result of either sampling errors or population inhomogeneity, then sterilization cycles can safely be set by extrapolation after the curve has entered its final linear phase. If nonlogarithmic survival is an intrinsic function of the organism itself, then conceivably gross errors can result from such extrapolation. This communication briefly describes a model based on chemical reaction kinetics in which non-logarithmic survival is inherent in the organism. Results are compared to data for Bacillus coagulans. Assume that microbes die independently, there is no reproduction, and the exposed population is homogeneous. Then, the expected population at time t is given by E [X (t)] = X (0) p (t) where X(0) is the initial population and p (t) is the probability of single spore survival to time t. Assume that in a thermal environment, microbial deaths result from chemical reactions which activate one or more of N independent death mechanisms, i.e., the microbe contains N vital systems such that survival depends on all N being functional. Then, the probability of single microbe survival to time t is given by
Calcium substitution in rare-earth metal germanides with the hexagonal Mn5Si3 structure type. structural characterization of the extended series RE5–xCaxGe3 (RE=Rare-earth metal)

Reported are the synthesis and the structural characterization of an extended family of rare-earth metal–germanides with a general formula RE5–xCaxGe3 (RE=Y, Ce–Nd, Sm, Gd–Tm and Lu; x<2). All twelve phases are isotypic, crystallizing with the Mn5Si3 structure type (Pearson index hP16, hexagonal space group P63/mcm); they are the Ca-substituted variants of the corresponding RE5Ge3 binaries. Across the series, despite some small variations in the Ca-uptake, the unit cell volumes decrease monotonically, following the lanthanide contraction. Temperature dependent DC magnetization measurements reveal paramagnetic behavior in the high temperature range, and the obtained effective moments are consistent with free-ion RE3+ ground state, as expected from prior studies of the binary RE5Ge3 phases. The onset of magnetic ordering is observed in the low temperature range, and complex magnetic interactions (ferromagnetic/ferrimagnetic) can be inferred, different from the binary phases RE5Ge3, which are known as antiferromagnetic. In order to understand the role of Ca in the bonding, the electronic structures of the La5Ge3 and the hypothetical compounds La2Ca3Ge3 and La3Ca2Ge3 with ordered metal atoms are compared and discussed.
The mass spectral rearrangements of aryl propenyl sulfones. An electron impact induced smiles type rearrangement

The mass spectral behavior of trans-1-arylsulfonyl-2-arylsulfenyl-propenes, trans-1-arylsulfonyl-2-arylsulfinyl-propenes and trans-1, 2-(arylsulfonyl)-propenes was examined. A Smiles type rearrangement was present in the sulfonyl-sulfides, but was completely absent in the trans-1-arylsulfonyl-2-arylsulfinyl-propenes and trans-1, 2-(arylsulfonyl)-propenes. Vinyl migration to the sulfone oxygen predominates over aryl migration in all of the compounds studied. The mass spectra of the cis and trans isomers of 1-p-tolylsulfenyl-2-p′-tolysulfonyl-propene and 1, 2-(p-tolylsulfonyl)-propene are also described.
Benzodiazepines specifically modulate GABA-mediated postsynaptic inhibition in cultured mammalian neurones

BENZODIAZEPINES (BDZ) such as diazepam (DZ) and chlordiazepoxide (CDZ) are commonly used anticonvulsants, muscle relaxants, antianxiety agents and hypnotics. The cellular mechanisms underlying these clinically important effects have not been established, but attention has been focused on the effect of BDZ on pre- and postsynaptic responses to the putative neurotransmitter amino acids, specifically glycine (Gly)1,2 and γ-aminobutyric acid (GABA)3–7. An effect of BDZ on postsynaptic Gly receptors was suggested by the finding that BDZ reduce strychnine binding to central nervous system (CNS) synaptic membrane fractions in vitro2, but physiological studies, in vivo, have provided little support for such an interaction with Gly3. BDZ have been reported (1) to facilitate presynaptic inhibition in the spinal cord4,5, at least partially GABA-mediated8–10; (2) to facilitate GABA-mediated pre- and postsynaptic inhibition in the cuneate nucleus6; (3) to mimic the presynaptic action of GABA on preganglionic nerve terminals12, and (4) to antagonise13,14 and to enhance15,16 the postsynaptic action of GABA on CNS neurones. It has also been suggested that BDZ alter GABA metabolism4,5 or mobilise GABA from neuronal storage sites17, and BDZ have been demonstrated to bind specific receptors on synaptosomal membrane preparations derived from rat brain18, an effect which is independent of amino acid receptors. Thus, it is uncertain whether BDZ action is GABA or Gly receptor-mediated, due to an alteration of GABA metabolism, or due to direct binding to a specific receptor which binds BDZ. We have studied the effect of DZ and CDZ on amino acid-mediated postsynaptic responses in cultured mammalian spinal cord neurones and report that the BDZ selectively modify GABA-mediated postsynaptic inhibition in a dose-dependent fashion, augmenting the response at low doses and antagonising the response at higher doses.
Relaxation factors for supercritical flows.

Relaxation procedures for solution of steady supercritical transonic flows are investigated. Von Neumann (Fourier-mode) stability analysis is used to find bounds of relaxation factors. The bounds depend on local Mach number and local mesh aspect ratio. Long wave instability of Murman-Cole implicit method is indicated. Two new relaxation procedures are introduced. Both employ central differencing exclusively. Group velocities of Fourier modes are used to study signal propagation. It was found necessary to avoid or to damp out signals propagating upstream in supersonic zones in order to obtain physically meaningful transonic solutions. It appears that requirements of high rate of convergence, of stability and accuracy, are in conflict, and that a combination of relaxation methods must be used in order not to compromise the requirements.
Evaluation of a capillary electrophoretic method for rapid screening of single-component combinatory libraries

The potential utility of capillary electrophoresis (CE) as an analysis and biological assay method for rapid screening of single-component combinatory libraries is demonstrated by mimicking a 5×5 drug matrix. Twenty-five compounds (some drugs, vitamins, metabolites, etc.) that include biotin are selected as the test analytes and avidin is treated as the biological activity screening reagent. In order to rapidly screen the compounds, five mixtures of nine components each are created at the diagonal of the matrix by pooling each component from the same column and row. The separation power of CE and related techniques is such that the components in these randomly generated nine-compound mixtures are almost always resolved using a single logical set of separation conditions. After obtaining optimum separation conditions, affinity testing produces the locations of the possible active component(s) based on changes in peak area. Blind tests are conducted that successfully locate the active component(s) of the matrix. With each test requiring about 14 separations (7 with and 7 without avidin) and each separation within 15 min, we were able to analyze the mixture and identify the exact locations of two possible active compounds (biotin and an unexpected compound) in the 5×5 matrix. The effect of avidin concentration on the screening procedure is assessed. Another protein, myglobin, was tested to compare specific and nonspecific interactions and to assign a threshold value (percent decrease in peak area) for determining a positive affinity response. © 1998 John Wiley & Sons, Inc. J Micro Sep 10: 653–660, 1998
Occupation measure for random walk on the circle

We give bounds on the probability of deviation of the occupation measure of an interval on the circle for random walk.
Boundary effects in second sound near Tλ

Abstract We investigate the effect of non-ideal boundary conditions applied to a second sound resonator near the lambda point. Appropriate boundary conditions for He-II are applied to a second sound resonator with a heater and detector at either end. We find the analytic boundary value solution for the homogeneous (zero gravity) differential equation. We show that the standing wave approximation is accurate to a few tenths of a percent at 10 −8 K from the transition.
Usablity and security trade-off: a design guideline

Requirements engineering and design are the first two phases of the Software Development Life-Cycle. Considerable research has addressed the requirements phase and a number of well-regarded tools exist to assist with that process. The design phase can also make use of a wide range of tools, including design principles, activities, best practices, techniques, and patterns, to improve the incorporation of requirements into the software design documents. However, the process of selecting the appropriate design tools to support each requirement is a complex task that requires considerable training and experience. It is also possible that design tools selected for different requirements can conflict with each other, reducing their effectiveness, increasing complexity, impacting usability or potentially causing security vulnerabilities. In this paper, we propose guidelines for selecting appropriate design tools to support the integration of usability and security requirements in the software design phase and to resolve conflicts between those tools. We demonstrate this approach with a case study that illustrates the design tool selection and analysis process.
Evidence of a heat-stress signal in etiolated pea epicotyls

Abstract Etiolated seedlings of Pisum sativum cv. Alaska were used as a source of a putative heat-stress signal. Production of this signal was found to increase in the cell wall fluid (apoplast) of etiolated stem segments after a 2-min pulse of heat (40°C). Apoplast fluid was collected from heated and unheated (control) stem segments by mild centrifugation. Apoplast fluid was applied to unheated segments which had been washed in an aerated water bath in order to reduce the level of wound ethylene. Ethylene production in the unheated segments was monitored following apoplast application. The apoplast fluid from heat-pulsed tissue significantly stimulated ethylene production in washed unheated segments. This apoplast fluid was found to contain elevated total protein and carbohydrate content. Ethylene-stimulating activity was primarily associated with the protein fraction of the apoplast fluid.
Possible role of sodium-calcium pumps in tension development of vascular smooth muscle.

Abstract Observations were made on the tension development by helical strips of vascular smooth muscle from rabbit aorta and mesenteric artery. Based on the possibility that the pump which moves calcium into the cell coupled with sodium efflux, recently described for squid axon (1), exists also in vascular smooth muscle, studies were designed to evaluate changes in its activity in this muscle. Sodium competes with calcium for the carrier at the cell surface, hence the pump moves calcium into the cell more rapidly in a sodium-free medium. The strips developed more tension in a sodium-free solution, as if more ionized calcium were being delivered to the cell. Ouabain is known to block the sodium-potassium pump, thereby permitting an increase in sodium concentration inside the cell; this in turn will aceclerate the sodium-calcium pump. Ouabain potentiated the contractile responses of these muscles, suggesting that a higher concentration of ionized calcium is reaching the contractile protein.
The Generation of ’Eighty

Before the argentine revolution of 1810, land was the principal source of wealth and the sanction of social position in the otherwise resourceless Viceroyalty of the Rio de la Plata. The revolution of May did not significantly alter the fundamental social, political and economic relationships between the masses of the people, the landowners and the soil. And although the administration of Rivadavia in the 1820’s and the dictatorship of Rosas in the next two decades were poles apart in their philosophies of society and government, each bore the same fruit in the further concentration of land in the hands of a relatively few men. After the fall of Rosas and the return of the exiled unitarios in 1852, the position of the landed gentry was not changed, despite the work of men like Urquiza, Mitre and Sarmiento, who applied themselves to the task of awaking Argentina from its long sleep of reaction. These victorious leaders were liberal and pragmatic, but there was no Argentine Homestead Act during their administrations. They accepted the land system as it was and tried to build upon it by spinning out the means of communication and transportation and technical development that would make it workable and by bringing in immigrants to make it fruitful. Aside from the establishment of a few colonies, the methods of land distribution and the laws of landownership remained essentially unchanged. Indeed, the governments that came after the Rosas regime, needful of revenue and concerned with the white elephant that was the government domain, embarked on much the same types of real estate deals as had the tyrant. In one case, in 1857, the government leased 3,000,000 hectares of land to 373 people; in 1867 Mitre’s government sold this land on easy terms to its renters.
Imaging modalities of craniosynostosis with surgical and pathological correlation.

Premature fusion of the sutures of the skull has been extensively analyzed and several diagnostic imaging modalities have been proposed. Radiographic, scintigraphic and computed tomographic features of craniosynostosis have been reported. This study was initiated (a) to determine the value and accuracy of plain skull radiography, skull scintigraphy and cranial CT; and (b) to determine the optimal imaging modality for the evaluation of a clinically suspected craniosynostosis. The study is based on 36 patients with clinical suspicion of craniosynostosis who underwent craniectomy and cranioplasty. One hundred and three sutures were pathologically and/or surgically evaluated. The overall accuracy rate for skull radiography was 89%, skull scintigraphy, 66%, and cranial CT, 94%. Routine skull series are adequate in the majority of cases of craniosynostosis. Skull scintigraphy is less accurate, more costly, and has a limited role in the evaluation of craniosynostosis. Cranial CT should be reserved for those cases in which the findings in the routine skull series are not clearly positive or negative, or in cases of more complex cranofacial anomalies.