cssi/SciSciGPT-SciSciNet huggingface dataset:
Chromium silicide-based composites fabricated via solid-state reactions: Phase development, oxidation behavior and electrical properties at high-temperatures

Abstract The chromium silicide-based electroconductive composites were fabricated by solid-state sintering of chromium silicide and chromium oxide powders at 1370 °C in argon. The final densified composites were composed of various solid solution and silicide phases (e.g. Cr3Si, Cr5Si3) and silica, depending on the starting silicide/oxide volume ratio ranging from 0.67 to 9.0. Major phases were found to be homogeneously distributed within the metastable (cristobalite) and/or amorphous silica grain boundary phase. The controlled oxidation experiments revealed excellent oxidation resistance at 50°-870 °C, where low-level oxidation was observed. The composites all displayed a metallic-type electrical conductivity due to the presence of the Cr3Si, Cr5Si3 and CrSi as the major conductive silicide phases. Their electrical conductivities ranged from 42.1 to 213.7 S/cm at 1000 °C. High-temperature annealing of the composites resulted in phase and microstructural changes, which further improved their high-temperature oxidation resistance and electrical transport properties.
Examining the Geologic Link of Arsenic Contamination in Groundwater in Orange County, North Carolina

Ingestion of inorganic arsenic through food and water can have severe adverse health effects on the human body. Therefore, government regulations and health guidelines for arsenic concentrations in water have been established around the world to avoid or mitigate these health effects. In recent decades, analysis of groundwater in many locations around the world have revealed arsenic concentrations that exceed government regulation levels. The section of the Carolina Terrane located in North Carolina is one of such recently discovered areas. This study investigates the relationship between the geologic units of the Carolina Terrane and arsenic concentrations in well water samples in Orange County, North Carolina. Kriging interpolation mapping and multivariate analysis reveals spatial and geochemical connections between wells of detectable arsenic and the "Neoproterozoic epiclastics" unit and geochemical variables such as F-, pH, and alkalinity. These associations imply that arsenic in Orange County, NC is being mobilized from authigenic arsenic-bearing sulfide minerals in the "Neoproterozoic epiclastics" bedrock unit by oxidative release likely associated with increased F-, pH, and alkalinity.
Reinventing the Wheel: The Economic Benefits of Wheeled Transportation in Early Colonial British West Africa

One of the great technological puzzles of Sub-Saharan African economic history is that wheeled transportation was barely used prior to the colonial period. Instead, head porterage was the main method of transportation. Though early colonial o¢ cials regarded this is highly ine¢ cient, the consensus amongst historians is that rather this was a rational adoption to the underlying conditions and factor endowments. In this paper we undertake the rst systematic investigation of the relative costs of these di¤erent forms of transportation and calculate the net economic bene ts and social savingsrepresented by the introduction of railway and motor transportation into British West Africa. While we nd that the net bene ts of the introduction of railways in the Gold Coast (Ghana) were positive, they are modest and rather similar as a proportion of national income to those calculated for the UK and US in the 19th century. Though these ndings reject the hypothesis that building railways was not economically rational in the Gold Coast, they can easily account for why it did not happen prior to the colonial period since African states were likely unable to enter international capital markets to raise the large amount of capital required for the initial xed cost of production. Very Preliminary and Incomplete Department of Political Science, 616 Serra St. Encina Hall West, Room 100, Stanford University, Stanford, CA 94305-6044, email: ichaves@stanford.edu. yUniversity of Rochester, Department of Economics and Department of History, Harkness Hall, University of Rochester, Rochester, NY14627, email: enge@troi.cc.rochester.edu. zHarvard University, Department of Government, IQSS, 1737 Cambridge Street N309, Cambridge, MA 01238; e-mail: jrobinson@gov.harvard.edu.
SReachTools: A MATLAB stochastic reachability toolbox: demo abstract

In this demo, we present SReachTools, an open-source MATLAB toolbox for performing stochastic reachability of linear, potentially time-varying, discrete-time systems that are perturbed by a stochastic disturbance [8]. The toolbox addresses the problem of stochastic reachability of a target tube, which also encompasses the terminal-time hitting reach-avoid [7] and viability problems [1]. As illustrated in Figure 1, the stochastic reachability of a target tube problem maximizes the likelihood that the state of a stochastic system will remain within a collection of time-varying target sets for a give time horizon, while respecting the system dynamics and bounded control authority [9]. We are interested in the computation of the stochastic reach set, denoted by LSR(α), which is the set of initial states that satisfy the reach/safety specification with a likelihood above α, and the associated optimal, admissible controller.
Risk factors for in-season injury in varsity collegiate cross-country athletes: an analysis of one season in 97 athletes.

Background Cross-country runners experience high rates of injury. This prospective cohort study aimed to identify pre-season risk factors for in-season injury in a cohort of collegiate cross-country athletes. Methods Pre-season and post-season electronic surveys were designed and administered to 297 NCAA Division I and III runners in August and November 2016, respectively. Pre-season surveys queried athletes' training methods, lifestyle habits, and history of previous injuries. Post-season surveys queried occurrence of new injuries sustained during the season. The risk of new injury was examined based on weekly mileage, sleep, diet, training routines, BMI, and history of previous injuries. Results Fifty-three percent of athletes sustained a new injury (acute injury or exacerbation of a chronic injury) during the season. In univariate analysis, the existence of a pre-season injury (RR 1.57, 95% CI 1.11-2.23, P=0.01), large mileage increases (RR 1.55, 95% CI 1.09-2.22, P=0.02), and poor sleep quality (P=0.04) were significantly associated with higher risk for injury among collegiate cross-country athletes. Conclusions Cross-country athletes with an existing injury during the pre-season, large mileage increases during the season, and poor sleep quality may be at increased risk of sustaining a new acute injury or exacerbate an existing injury during the cross-country season. Coaches, athletic trainers, and athletes can use these results to modify training regimens and lifestyle factors to decrease the risk of injury.
N2O Reductase Activity of a [Cu4S] Cluster in the 4CuI Redox State Modulated by Hydrogen Bond Donors and Proton Relays in the Secondary Coordination Sphere

The model complex [Cu4 (μ4 -S)(dppa)4 ]2+ (1, dppa=μ2 -(Ph2 P)2 NH) has N2 O reductase activity in methanol solvent, mediating 2 H+ /2 e- reduction of N2 O to N2 +H2 O in the presence of an exogenous electron donor (CoCp2 ). A stoichiometric product with two deprotonated dppa ligands was characterized, indicating a key role of second-sphere N-H residues as proton donors during N2 O reduction. The activity of 1 towards N2 O was suppressed in solvents that are unable to provide hydrogen bonding to the second-sphere N-H groups. Structural and computational data indicate that second-sphere hydrogen bonding induces structural distortion of the [Cu4 S] active site, accessing a strained geometry with enhanced reactivity due to localization of electron density along a dicopper edge site. The behavior of 1 mimics aspects of the CuZ catalytic site of nitrous oxide reductase: activity in the 4CuI :1S redox state, use of a second-sphere proton donor, and reactivity dependence on both primary and secondary sphere effects.
Putting anthropology in its (hospitable) place: Harry Shapiro’s fieldwork on Pitcairn Island, 1934–1935

This paper examines American physical anthropologist Harry Shapiro’s anthropometric fieldwork on Pitcairn Island in 1934–1935 to argue for hospitality as a vital subject of and analytic framework f...
Evaluation of Pragmatic Methods to Rapidly Assess Habitual Beverage Intake and Hydration Status in U.S. Collegiate Athletes

Fluid intake recommendations have been established for the athletic population in order to promote adequate hydration. The Beverage Intake Questionnaire (BEVQ-15) is a quick and reliable food frequency questionnaire that quantifies habitual beverage intake, which has been validated in children, adolescents, and adults. However, no validated beverage consumption questionnaire is available for collegiate athletes. Urine color (UC), while feasible for determining hydration status, has not been validated within a variety of collegiate athletes. The purpose of this investigation was to evaluate the comparative validity and reliability of pragmatic methods to rapidly assess BEVQ-15 and UC rating in U.S. Division I collegiate athletes. Student-athletes (n = 120; 54% females; age 19 ± 1 years) from two universities were recruited to complete three study sessions. At the first and third sessions, the participants completed the BEVQ-15 and provided a urine sample to determine UC and urinary specific gravity. All sessions included completion of a 24-hr dietary recall. Total fluid intake (fl oz) was 111 ± 107 and 108 ± 42 using the BEVQ-15 and the mean of three 24-hr dietary recalls, respectively, which was not different between methods (p > .05). There were moderate associations between the BEVQ-15 and dietary recall results for total beverage intake fl oz and kcal(r = .413 and r = 4.65; p ≤ .05, respectively). Strong associations were noted between both researcher-rated and participant-rated UC with urinary specific gravity measures (r = .675 and r = .884; p ≤ .05, respectively). Therefore, these rapid assessment methods demonstrated acceptable validity and may be used as practical methods to determine whether athletes are meeting their hydration recommendations.
Clinical Indicators for Long-Term Survival with Immune Checkpoint Therapy in Advanced Hepatocellular Carcinoma

Introduction Patients with advanced hepatocellular carcinoma have a dismal prognosis; only a subset of patients with advanced HCC will benefit from treatment with immunotherapy. We searched for clinical characteristics predicting exceptional long-term survival in HCC patients treated with immune checkpoint inhibitors. Methods We compared clinical characteristics of 59 patients with advanced hepatocellular carcinoma treated with immunotherapy with and without locoregional therapy between 2013-2019. We compared patients who lived less than 12 months with patients who lived more than 3 years. Traits of short-term (31 patients) and long-term (5 patients) survivors were compared. Patients who died between 12 months and 3 years of starting treatment on protocol were not included in the analysis. Results Two out of five patients (40%) in the long-term survival group had a partial response (PR) or a complete response (CR) per the modified Response Evaluation Criteria in Solid Tumors (mRECIST), while, of the 31 patients in the short-term survival group, only 2 (6.5%) had a CR or PR. Two of the 5 patients with a long-term survival had immune-related adverse events grade 3 or 4 (IrAEs-3/4). None of the patients in the short-term survival group had IrAEs-3/4. The patients, who presented with IrAEs-3/4, which included colitis and adrenal insufficiency, continued to have a response off treatment. The median overall survival (OS) was 11.8 months (95% CI: 7.8-15.4 months), with a 12-month OS of 46.6% (95% CI: 33.4-58.8%) and a 3-year OS of 12.5% (95% CI: 5.0-23.7%). Conclusion We found a possible association between immune-related adverse events grade 3 and 4 and long-term survival in patients with advanced HCC. The cases in our analysis represent extraordinary defiance of the usual predicted dismal course of advanced HCC.
Regulatory T cell activation, proliferation, and reprogramming induced by extracellular vesicles.

Background Extracellular vesicles (EVs) from heart stromal/progenitor cells modulate innate immunity, with salutary effects in a variety of cardiac disease models. Little is known, however, about the effects of these EVs on adaptive immunity. Methods Ex vivo differentiation of naive CD4+ T cells was conducted to assess the effect of EVs on cytokine production and proliferation of Th1, Th2, Th17, and regulatory T (T reg) cells. These effects were further tested in vivo using the experimental autoimmune myocarditis (EAM) model. Results Using differentiated CD4+ T cells, we show that EVs secreted by human-derived heart stromal/progenitor cells selectively influence the phenotype, activity, and proliferation of regulatory T (Treg) cells. Exposure of Treg cells to EVs results in faster proliferation, augmented production of IL-10, and polarization toward an intermediate FOXP3+RORγt+ phenotype. In experimental autoimmune myocarditis, EVs attenuate cardiac inflammation and functional decline, in association with increased numbers of splenic IL10 +-Treg cells. Conclusions T cell modulation by EVs represents a novel therapeutic approach to inflammation, harnessing endogenous immunosuppressive mechanisms that may be applied in solid organ transplantation , graft-versus-host disease, and autoimmune disorders.
Mental Graphs

I argue that Frege Problems in thought are best modeled using graph-theoretic machinery; and that these problems can arise even when subjects associate all the same qualitative properties to the object they’re thinking of twice. I compare the proposed treatment to similar ideas by Heck, Ninan, Recanati, Kamp and Asher, Fodor, and others.
Near Geogrid Stiffness Quantification in Airport Pavement Base Layers Using Bender Element Field Sensor

Geogrids are widely used for unbound aggregate base stabilization in flexible pavements. A new field evaluation methodology for quantifying the effects of geogrids on stiffness enhancement of unbound aggregate layers is demonstrated in this paper. The method utilizes a bender element field sensor, which measures the shear wave velocity transmitted between a source and receiver pair of bender element (BE) transducers and relates that to the localized stiffness. The paper introduces the new methodology and discusses the recent measurements obtained from a geogrid–aggregate system stiffened zone in the full-scale Construction Cycle 9 (CC9) pavement test sections constructed at the Federal Aviation Administration’s (FAA’s) National Airport Pavement Test Facility (NAPTF) in New Jersey. The aggregate materials used in the construction of the base and subbase layers were in accordance with the FAA-designated P-209 and P-154 specifications, respectively. A biaxial geogrid was placed at the interface between the subbase and base in the “North” test section. Two BE field sensors were installed in this “North” geogrid-stabilized section at 25 mm (1-in.) and 102 mm (4 in.) above the geogrid location. A third sensor was installed in the “South” control section with no geogrid at 25 mm (1 in.) above the bottom of the base layer. Shear wave signals were collected before and after base layer compaction, and shear wave velocities were calculated. The BE field sensor measurements clearly indicated that stiffness enhancement was achieved in the proximity of the geogrid, and that such effect of a stiffness enhancement diminished at about 102 mm (4 in.) away from the geogrid. The findings of this study are illustrated in this paper to quantify the magnitude and extent of the local stiffened zone near a geogrid.
Chalmers–Metcalf Operator and Uniqueness of Minimal Projections in ℓ n ∞ and ℓ n 1 Spaces

We construct the Chalmers–Metcalf operator for minimal projections onto hyperplanes in l ∞ n and l 1 n and prove it is uniquely determined. We show how we can use Chalmers–Metcalf operator to obtain uniqueness of minimal projections. The main advantage of our approach is that it is purely algebraical and does not require consideration of the min–max problems.
What to do About Journalism? Journalism and the International academic world

I begin with a question that may seem to be labor the point to readers of this article but which I believe holds some of the key issues associated with contemporary journalism.“What to do about journalism?” is a question that has not only conceptual dimensions – as in what do we study when we think about journalism -- but also pedagogic ones -- how do we teach what we think we know – and, most importantly, pragmatic ones – what is journalism today? And how will we continue practicing it into the coming era? on this article I would like to think through some of the most important challenges facing the study of contemporary journalism. I’ll be drawing from my own work that has been somewhat focused on the fundamental question of what journalism is for.
Clinical validation of an automated boundary tracking algorithm using cardiac MR images

Manual tracing of ventricular borders in MRI images is a tedious process. The goal of this research was to develop an algorithm for tracking the borders of the left ventricle (LV) in a cine-MRI gradient-echo temporal data set. The algorithm was validated on healthy volunteers and patients with dilated cardiomyopathy (DCM) before and after surgical remodeling of the LV. A full tomographic set (/spl sim/11 slices/case) of short axis images were obtained through systole. Initial endocardial and epicardial contours for the end-diastolic (ED) and end-systolic (ES) phases were manually traced on the computer by an expert. The initial tracing of the ED borders were used as starting point. These borders were then temporally tracked through each phase of the temporal data set, until the ES phase was reached (/spl sim/7 phases/slice). Peak gradients along equally spaced chords calculated perpendicular to centerline determined midway between the endocardial and epicardial borders were used for border detection. This approach was tested by comparing the LV epicardial and endocardial volumes calculated at ES to those based on the tracings by an expert. The LV volumes based on the borders obtained from the automated algorithm correlated well with those calculated from the expert manual tracings.
Exploitation of host cell processes for bacterial cell-to-cell spread (99.4)

The ubiquitous food-borne bacterium Listeria monocytogenes causes spontaneous abortion in pregnant women and meningitis in immune-compromised hosts. Bacteria in the intestine directly invade intest...
Positive and negative regulatory mechanisms that mediate long-term memory storage

The protein kinase A pathway and the cyclic AMP-response element binding protein (CREB) appear to play a critical role in the consolidation of short-term changes in neuronal activity into long-term memory storage in a variety of systems ranging from the gill and siphon withdrawal reflex in Aplysia to olfactory conditioning in Drosophila to spatial and contextual learning in mice. In this review we describe the molecular machinery that mediates memory consolidation in each of these systems. One of the surprising findings to emerge, particularly from studies of long-term facilitation in Aplysia, is that memory storage is mediated by not only positive but also negative regulatory mechanisms, in much the same way as cell division is controlled by the proteins encoded by oncogenes and tumor suppressor genes. This suggests the interesting possibility that there are memory suppressor genes whose protein products impede memory storage.
Towards an ISP-compliant, peer-friendly design for peer-to-peer networks

Peer-to-peer (P2P) applications are consuming a significant fraction of the total bandwidth of Internet service providers (ISPs). This has become a financial burden to ISPs and if not well addressed may lead ISPs to block or put strict rate limits on P2P traffic. In this paper, we propose a new framework, PCP, for designing P2P applications to smoothly fit into the global Internet. In our framework, an ISP decides on how much of its bandwidth is to be allocated to P2P clients, and P2P clients inside the network adopt a peer-friendly algorithm to fairly share the bandwidth. Using the widely-used percentile-based charging model and real traffic traces, we show that an ISP can allocate a large amount of bandwidth dedicated to P2P, without increasing its financial cost. We also show that P2P clients can use the algorithm to fairly share the allocated bandwidth.
Fundamentals of Thermal Properties

Before we discuss the atomistic and quantum mechanical theories of the thermal properties of materials, we need to remind the reader on some relevant fundamental concepts and definitions which you might have been exposed to before in courses of physics and thermodynamics.
Missed symptoms of menopause.

Summary Objective: This review examines the available data on the efficacy of selective serotonin reuptake inhibitors (SSRIs) and serotonin–noradrenaline reuptake inhibitors (SNRIs) for treating the commonly missed climacteric symptoms of menopause. Discussion: Although some women may pass through the menopausal transition phase with few or no symptoms, the majority experience one or more symptoms serious enough to be disruptive to their lives. The most common are vasomotor symptoms (VMS; hot flushes and night sweats), but they are not the only climacteric symptoms that can negatively affect quality of life. The ‘missed symptoms’ of menopause – symptoms with high prevalence and an impact on quality of life that nonetheless receive less attention than do VMS – include mood changes, sleep disturbances and somatic complaints. These symptoms are reported by approximately half of menopausal women, with numbers varying by region and ethnic background. As with VMS, the effects of declining oestrogen levels on serotonin/noradrenaline pathways could play a role in their development. Conclusions: Results from pilot studies of several SSRIs and SNRIs suggest that they may improve menopausal mood and sleep symptoms, but few studies have demonstrated significant improvement compared with placebo. One SNRI (venlafaxine) improved menopausal mood symptoms and two SSRIs (citalopram and paroxetine) improved sleep, each in a single placebo-controlled trial of women with VMS. Additional placebo-controlled trials are needed to determine whether SSRIs or SNRIs are effective treatment options for women who cannot or choose not to use hormone therapy.
Anti-aging medicine

Today's healthcare challenges and tomorrow's opportunity can only be met by those who search out deeper explanations of the body processes that generate health and disease. Life expectancy has increased due to advances in medical science. However it has come with little progress towards quality of life or the length of disease-free years in the majority of population. Most researchers believe that maximum life span in human is slightly over 110 years. Beyond that age, the estimates and speculation enter the realms of science fiction.
THE Mu TRANSPOSABLE ELEMENTS OF MAIZE: EVIDENCE FOR TRANSPOSITION AND COPY NUMBER REGULATION DURING DEVELOPMENT

The Mu transposon of maize exists in a highly mutagenic strain called Robertson's Mutator. Plants of this strain contain 10-50 copies of the Mu element, whereas most maize strains and other plants have none. When Mutator plants are crossed to plants of the inbred line 1S2P, which does not have copies of Mu, the progeny plants have approximately the same number of Mu sequences as did their Mutator parent. Approximately one-half of these copies have segregated from their parent and one-half have arisen by transposition and are integrated into new positions in the genome. This maintenance of copy number can be accounted for by an extremely high rate of transposition of the Mu elements (10-15 transpositions per gamete per generation). When Mutator plants are self-pollinated, the progeny double their Mu copy number in the first generation, but maintain a constant number of Mu sequences with subsequent self-pollinations. Transposition of Mu and the events that lead to copy number maintenance occur very late in the development of the germ cells but before fertilization. A larger version of the Mu element transposes but is not necessary for transposition of the Mu sequences. The progeny of crosses with a Mutator plant occasionally lack Mutator activity; these strains retain copies of the Mu element, but these elements no longer transpose.
Ion transport: spot the difference.

Common wisdom holds that ion channels and ion pumps, with their obvious functional differences, should have visibly dissimilar structures. It seems that's not necessarily so.
Blood group antigen expression in developing pancreas and in induced pancreatic cancer cells in Syrian hamsters

Expression of blood group-related antigens and the binding pattern of Ulex europaeus-I (UEA-I) in fetal and newborn hamster pancreases was examined immunohistochemically by monoclonal antibodies (MoAbs) against blood group antigens and by peroxidase-conjugated UEA-I. The fetal hamster pancreas was detected histologically at the 12th day of gestation. MoAbs A, B and Le(a) were not immunoreactive with pancreatic cells in any stage of development nor were they after birth. Le(x) was first expressed in the luminal surface of duct cells at the 13th day of gestation, disappeared at the 15th day of gestation, was re-expressed after birth in acinar cells and was absent in the adult pancreas. Le(b) and Le(y) were expressed in acinar cells in late fetal and early newborn stages, but disappeared with maturation and were absent in the adult pancreas. UEA-I binding, however, was demonstrated in both fetal and adult pancreatic tissue. In cancer cells induced by BOP, blood group antigens except for Le(a) and UEA-I binding were found in various reactivity. These findings suggest that in hamsters (i) A and B antigens are tumor-related antigens; (ii) H, Le(b), Le(x) and Le(y) are oncofetal antigens; and (iii) fucosylation is an important event in cell differentiation.
The Effect of BWR Startup Environments on Crack Growth in Structural Alloys

During startup of a boiling water reactor (BWR), the water chemistry and temperature are constantly changing. Special operational practices can be performed to control the dissolved oxygen level using, for example, vacuum deaeration. To assess the impact of startup practice on environmental cracking in the structural materials used in the BWR, a large program was performed to evaluate crack growth at representative environmental conditions for both conventional and vacuum deaeration startup practices. Five alloys were studied: types 304 and 316 nuclear grade stainless steel, Inconel 600, carbon steel, and A508-2 low alloy steel. Tests were performed using fracture mechanics type specimens with constant load crack growth measured at appropriate stress intensity levels. The program intent was to compare the crack growth rates for the two practices. The results show that normal startup and startup deaeration environments had varied effects. Sensitized type 304 stainless steel exhibited a decrease in crack growth rate and concomitant decrease in severity of intergranular fracture morphology at the low temperatures under deaeration. In contrast, the type 316 nuclear grade displayed very little influence of startup deaeration due to its inherent resistance to stress corrosion cracking. Inconel 600 showed up to a factor of five reduction inmore » crack growth rate in the deaeration environment.« less
Fluidisation as a feeding mechanism in beach flies.

WE have seen groups of small (4–5 mm long) grey flies belonging to the species Lipochaeta slossonae Coquillett, 1896, standing, shaking and apparently feeding, or flying for short distances on stretches of wet sandy beach in La Jolla, California and San Felipe, Mexico. When undisturbed, they walked sideways or stood and shook their bodies, diagonally forward and downward, and backwards and upwards, at an estimated frequency of 5 s−1. We guessed that they were fluidising the wet sand under their feet and thereby loosening some of the interstitial microflora which could then be sucked up as a kind of soup. This was confirmed by laboratory examination of the guts of several specimens, which contained the remains of large numbers of cells of dinoflagellates and diatoms. (The species of dinoflagellates were unfortunately unidentifiable since there were no cell wall remains, but they probably belonged to the genus Amphidinium, which comprises some of the commonest unarmoured interstitial dinoflagellates on this beach. The diatom species, however, could be readily identified by their silica walls. There were at least 10 genera, all typical of the marine interstitial community, including various species of Navicula, Nitzschia, Pinnularia and Amphora.)
Fluorochrome Labeled Bone (Part I): Long-term Fixation Results

AbstractLaboratories investigating dental and bone diseases or orthopedic implant devices have used fluorochrome labels to quantify bone growth for over 40 years. Bone fixation with 10% neutral buffered formalin has been used by many of these laboratories. Routine practice has been to fix the bone samples in formalin for no more than 48 hr, wash them in water, and place the specimens in 40–70% ethanol for further fixation and/or storage. This paper reports a study that builds on a previous investigation and demonstrates fixation of bones for up to 1 yr in 10% neutral buffered formalin caused no evident loss of fluorochrome labels. However, the study also demonstrates that fixation in Safefix® at 1 yr caused mixed results. Although most of the 1 yr slides exhibited no apparent fading of the fluorochromes, there were two slides that did have fading of the labels. (The J Histotechnol 25:99, 2002)Submitted March 15, 2002; accepted April 5, 2002
Aggregates of tubules in human cardiac muscle cells

Abstract Two types of aggregated tubules derived from, and continuous with, elements of sarcoplasmic reticulum were observed in degenerated cardiac muscle cells from patients with cardiac hypertrophy. Aggregates of the first type, found in 2 patients, were composed of long, parallel tubules which measured from 500 to 1130 A in diameter and showed different degrees of organization. In some of these aggregates the tubules were irregularly arranged and were closely associated with large masses of abnormal Z band material to which thin myofilaments were attached. In other instances, the tubules formed highly regular, hexagonally arranged aggregates; the spaces between these aggregated tubules contained thin myofilaments and small amounts of Z band material. Cells in which these aggregates were present showed advanced degenerative changes characterized by disarray of myofibrils, absence of T tubules, and selective loss of thick myofilaments. It is concluded that the formation of these aggregates of tubules derived from the sarcoplasmic reticulum is a degenerative change related to the inability of the sarcoplasmic reticulum to form meshworks around abnormally constituted myofibrils, or terminal cisterns around T tubules. Aggregates of the second type, found in one patient, were formed by long, straight, irregularly arranged tubules that measured 500 to 830 A in diameter and were not associated with myofibrillar components. These aggregates are considered to represent an unusual type of proliferation of the sarcoplasmic reticulum in cells having normally arranged contractile elements.
Parathyroid hormone secretion in magnesium deficiency

The effect of an acute elevation of the serum magnesium concentration on the concentrations of serum immunoreactive parathyroid hormone (IPTH) were studied in hypocalcemic hypomagnesemic patients, hyperparathyroid patients, and normal individuals. Basal serum IPTH concentrations in the hypomagnesemic patients ranged from undetectable to 3 times the upper limit of normal. All hypomagnesemic patients were observed to have an immediate rise in the serum IPTH concentration after magnesium administration regardless of the basal IPTH concentration. In contrast, normal individuals and patients with primary and secondary hyperparathyroidism responded to magnesium administration with either a decrease or little change in the serum IPTH concentration. These date indicate that an acute stimulation of PTH secretion induced by magnesium is characteristic of the magnesium-deficient state. The consistency of this response suggests that impaired PTH secretion is a significant factor contributing to the hypocalcemia of magnesium deficiency.
Origin of spurious ultrasonic echoes in stainless steel piping with weld overlay

The initiation and growth of intergranular stress-corrosion cracking (IGSCC) in the heat-affected zone of welds in stainless steel reactor piping has been a subject of concern to electric utilities for over ten years. This type of crack can be detected with ultrasonic shear waves during normal maintenance periods with a reliability of up to 80% [1]. Often, when crack indications have been found, the utility has been allowed to apply a weld metal overlay as a temporary repair measure. However, the complex, elastically anisotropic microstructure of the overlay considerably reduces the reliability of subsequent ultrasonic inspections. This paper addresses the problems arising because of the overlay.
Performance of Community Dwelling Elderly on the Timed Up and Go Test

The purpose of this study was to determine mean performance times and the effect of age and gender on the Up and Go (UG) with and without a cane. UG measures the time required to stand up from an a...
Childhood polymyositis/ dermatomyositis

Children with PM/DM differ in many respects from adults with PM/DM. The most characteristic and distinctive feature is the presence of a widespread vasculopathy. Although the pathogenesis is unknown, roles for both humoral and cell-mediated immunity have been proposed. Most intriguing is the evidence for a viral agent that is capable of precipitating an ongoing, immunologically mediated reaction damaging muscles and endothelial cells. Much remains to be discovered, however, regarding the pathogenesis of this disease.
A Study of the Molecular Weight Distribution of Poly(Amino Acid)s Synthesized by Diphenyl Phosphoryl Azide

Abstract Direct polycondensations of β-benzyl-l-aspartate (Asp.Bz) and β-benzyl-l-glutamate (Glu.Bz) were carried out in the presence of diphenyl phosphoryl azide (DPPA) as a condensation agent and triethyl amine (TEA). Poly(amino acid)s were obtained by this convenient approach whose structure was confirmed by IR and 1H-NMR spectroscopy. The effects of the monomer concentration, the polymerization time and temperature, the ratios [DPPA]/[monomer] and [TEA]/[monomer], and the solvent used on the molecular weight distribution of the polymer were studied. When the monomer concentrations were higher than 0.2 g/mL, poly(Asp.Bz) with a bimodal molecular weight distribution was obtained (Mw of 37,000 and Mw/Mn of 1.68). The polycondensations carried out in THF or in bulk provided the highest molecular weight (Mw ⋍ 40,000). Several other amino acids were also polymerized by DPPA.
Relationship of clinical features with psychological status in primary fibromyalgia

Clinical features and psychological status determined by the Minnesota Multiphasic Personality Inventory (MMPI) in 103 patients with primary fibromyalgia syndrome (PFS) were analyzed by univariate and multivariate techniques to determine if clinical features were related to psychological status or were intrinsic to PFS per se. The central features of PFS, e.g., number of pain sites, number of tender points, fatigue, and poor sleep, were independent of psychological status. However, discriminant analysis identified 4 variables--patient-reported depression, anxiety, stress, and pain severity--which together predicted 3 MMPI subgroups with an accuracy of 55% (P less than 0.001); the only musculoskeletal feature--pain severity--alone provided an accuracy of only 34% (P greater than 0.05). These data suggest a new concept, that the central features of fibromyalgia are independent of the psychological status and are more likely related to the PFS itself. However, pain severity may be influenced by psychological factors.
Local distortions and Friedel oscillations in interacting Fermi chains

The interplay between disorder and interaction, especially near metal insulator transitions, is a long-standing question. We investigate in detail single impurities, in particular, the Friedel oscillations induced by them. We study the decay of the Friedel oscillations in the one-dimensional Heisenberg and Hubbard model analytically using the bosonization technique and numerically using the density matrix renormalization group treatment (DMRG). For the Heisenberg chain, we confirm the predictions of conformal field theory and bosonization for small interaction, but near phase transitions deviations are found in form of vanishing or additional oscillations. For the Hubbard chain, we study the oscillations – in the density as well as in the magnetization – in the spin-gap, charge-gap, and Luttinger liquid phase. We find an exponential decay or a very slow algebraic decay of the oscillations in the gapped phases. In the Luttinger liquid phase, we concentrate on the question of logarithmic corrections (which occur also in the isotropic Heisenberg antiferromagnet). Differences in the behavior near a boundary compared to an impurity are pointed out. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
Fragmentation instabilities in nuclear systems

The fragmentation of nuclear systems, formed in proton- and heavy-ion-induced reactions in a wide energy range, is examined. The dependence of the fragment production cross section on the incident energy and on the temperature of the emitting source is compared to predictions of a theory of condensation. We find many instances where the fragmentation instability can be explained by and may be attributed to a liquid-gas phase transition. Our analysis suggests the occurrence of instabilities at a critical temperature of approximately 11 to 12 MeV, in accord with several theoretical predictions. Conventional nuclear effects, such as Coulomb barrier penetration, cannot fully describe the observed phenomena.
On obstructions in relation to a fixed viewpoint

108 Efficient, randomized algorithms are given for the following problems: (1) construction of levels of order 1 to k in an arrangement of hyperplanes in any dimension; (2) construction of higher order Voronoi diagrams of order 1 to k in any dimension; (3) hidden surface removal for completely general scenes (intersecting and curved faces are allowed). A combinatorial tool in the form of a mathematical series called a theta series is associated with a configuration of polytopes in R/sup d/. It is used to study the combinatorial, as well as algorithmic, complexity of the geometric problems under consideration. >
Finding least common ancestors in directed acyclic graphs

One of the fundamental algorithmic problems on trees is how to find the least common ancestor (LCA) of a given pair of nodes. The LCA of nodes u and v in a tree is an ancestor of u and v that is located farthest from the root. The LCA problem is stated as follows: Given a rooted tree T, how can we preprocess T to answer LCA queries quickly on any pair of nodes? The LCA problem has been studied intensively both because it is inherently beautiful and because fast algorithms for the LCA problem can be used to solve other algorithmic problems. However, many similar combinatorial problems cannot be solved using the tree LCA algorithmic machinery because the ancestor queries are on more complicated directed structures. Examples of such combinatorial problems include preprocessing arbitrarily (unrooted) directed trees [NU94], computing the LCA on lattices (used to represent inheritance graphs) [AKBLN89], and finding modular coverings in inheritance graphs [DH87, HHS95]. In this paper we introduce a natural extension to all of these LCA problems. We develop algorithms for efficiently answering least common ancestor queries on directed acyclic graphs (DAGs). An LCA w of nodes u and v in a DAG is an ancestor of both u and v where w has no descendants that are ancestors of both u and v. (See Definitions 2.1 and 2.2.) We present an o(n 3) preprocessing algorithm for answering least common ancestor queries on DAGs in constant time. We then initiate an experimental study of new and existing LCA algorithms on rooted trees and DAGs. Least common ancestor queries on general DAGs appear in a variety of applications, including the following:
Effect of Beak Trimming on Body Weight and Feed Intake of Broiler Roasters Fed Pellets or Mash

Abstract Two trials were conducted to determine the effect of beak trimming on feed intake and growth of roasters when feed is in mash or pellet form. Roasters were beak trimmed at 50 days of age by removing one-third or one-half of the top beak only or a block cut with one-half of the top and bottom beak removed. After beak trimming, for roasters fed mash, feed consumption and weight gain depressions were observed from 50 to 56 days of age, and then normal feed consumption and weight gain from 56 to 70 days, compared with corresponding values for mash-fed controls. After beak trimming, roasters fed firm pellets with essentially no fines experienced feed consumption and weight gain depressions from 50 to 70 days of age compared with corresponding values for controls. When birds were changed from mash to pellet diets at 42 days of age, a significant initial increase in feed intake and body weight gain occurred for broilers receiving the pelleted diet when compared with broilers receiving the mash diet.
University Faculty Describe their Use of Moving Images in Teaching and Learning and their Perceptions of the Library’s Role in that Use

The moving image plays a significant role in teaching and learning; faculty in a variety of disciplines consider it a crucial component of their coursework. Yet little has been written about how faculty identify, obtain, and use these resources and what role the library plays. This study, which engaged teaching faculty in a dialogue with library faculty, revealed a gap between faculty’s film and video information retrieval needs and provision of access by the library. Ultimately, the findings of this study can inform and transform library practices to make more moving images available for use in coursework and research.
Severe graft-versus-host disease in a liver-transplant recipient.

CLINICALLY evident generalized graft-versus-host disease is not thought to occur as a consequence of transplantation of most solid organs. The requisite large inoculum of donor lymphoid cells and inability of the recipient to destroy these passenger cells1 are apparently rarely produced by solid-organ transplantation. However, there is a high risk of graft-versus-host disease when normal spleens are included in vascularized pancreas-transplants.2 3 4 5 We report on a case of severe generalized acute graft-versus-host disease in a recipient of a liver transplant, involving documented transient chimerism of donor origin. This life-threatening complication was treated successfully with increases in the corticosteroid dosage and the . . .
Organic Molecular Films under Shear Forces: Fluid and Solid Langmuir Monolayers

Scanning probe microscope observations of monolayers of a classic boundary lubricant, stearic acid (STA), reveal long-range dynamics of wear and reconstruction of monomolecular films under the shea...
Oral squamous cell carcinoma in a patient with keratitis-ichthyosis-deafness syndrome: A rare case

Keratitis-ichthyosis-deafness (KID) syndrome is a rare form of ectodermal dysplasia with significant visual and auditory impairment. Pathogenesis involves a mutation in the GJB2 gene, which encodes connexin-26, a protein in the epithelial gap junctions thought to be involved in the differentiation of ectodermally derived tissues. Affected patients are also at increased risk for the epithelial malignancies. To our knowledge, nearly 100 cases of KID syndrome, including 19 with squamous cell carcinoma (SCC) complications, have been reported worldwide. We report here a patient with KID syndrome who developed an ulcerative oral lesion causing him significant discomfort; he was subsequently diagnosed with oral SCC. We review the clinical presentation and symptomatology, including those affecting the oral cavity for this syndrome and highlight the importance of multidisciplinary collaboration and life-long screening aimed at prevention of the evolving complications.
Facilitating Intercultural Communication in Parent–Teacher Conferences: Lessons From Child Translators

Maria was a fifth grade student when the authors met her in a study of immigrant child-language brokers. Her family immigrated from a farming community in Mexico to a Chicago suburb where there wer...
CONDITIONS OF THE ASCENDING AORTA SIMULATING AORTIC VALVULAR INCOMPETENCE.

Abstract Abnormal run-off of blood from the ascending aorta may result either from primary diseases of the aortic valve or from primary diseases of the ascending aorta. Primary diseases of the ascending aorta which allow abnormal escape of blood from the aorta fall into two categories. The first includes those conditions which, by virtue of the distortion or dilatation of the ascending aorta, cause the aortic valve to become incompetent. The route for abnormal escape of blood in these situations is through the aortic valve. In the second the aorta communicates abnormally with a cardiac structure or a mediastinal blood vessel. Congenital, traumatic and infectious conditions constitute the major backgrounds for this second type of functional derangement.
Conflicts of Interest in Clinical Practice Guidelines

Clinical practice guidelines are used increasingly across medical specialties and settings, making evaluation of their utility and validity a critical public health issue. In this paper, we describe some of the challenges that specialty organizations face as they try to ensure that their guidelines are trustworthy and useful. We examine the practice guidelines for Major Depressive Disorder recently published by the American Psychiatric Association (APA), identify five sources of potential bias that may affect the guideline development process and offer suggestions based on our review. For example, even for mild depression, this guideline privileges pharmacotherapy over other interventions, despite questions about the risk/benefit ratio and the increasing concern over the iatrogenic harms of SSRIs and SNRIs. We compare recommendations from international scientific groups (e.g. NICE) with those produced by specialty societies in an effort to demonstrate some of the ways in which conflicts of interest, both intellectual and financial, may unduly influence guidelines.
On the Design of Horizontal Axis Two-Bladed Hinged Wind Turbines

Hinged two-bladed wind turbines are not necessarily free of disturbing vibrations. The combination of elastic or built-in blade coning with blade flapping about a conventional teeter hinge produces periodic blade angular velocity variations in the blade tip path plane with associated vibrations and dynamic loads. The paper discusses and evaluates various hinge configurations for two-bladed rotors and shows why the conventional teeter hinge leads to nonuniform blade angular velocity in the blade tip path plane. The solution to this problem adopted for two-bladed helicopter rotors, though complex, could be of interest for large wind turbines. A much simpler solution, calling for the suppression of blade flapping by passive blade cyclic pitch variation produced by a strong negative pitch-flap coupling, was found to be practical for upwind tail vane stabilized two-bladed wind turbines.