cssi/SciSciGPT-SciSciNet huggingface dataset:
Nanotoxicology in Green Nanoscience

Nanotechnology holds great promise for future economical and technological advances, yet health and safety concerns regarding nanomaterials persist. As an emerging technology, nanotechnology is in the unique position to proactively address health and safety concerns throughout the product life cycle. Green chemistry aims to create benign compounds in a way that prevents pollution and reduces waste throughout every stage of production. Through green nanoscience, the principles of green chemistry can be applied toward making high performance, yet inherently safe nanomaterials. Successful application of green chemistry principles to assess nanomaterial health and safety requires efficient, predictive, high-throughput nanotoxicity testing. With these approaches, designers and manufacturers of nanomaterials can assess nanotoxicity early in production to redesign or replace hazardous nanomaterials.
Pathophysiological Insights into Persistent Hyponatremia after LVAD Implantation

Background Persistent hyponatremia after LVAD implantation is not uncommon in patients with end-stage heart failure (HF) and maybe associated with adverse outcomes. The etiology of hyponatremia in HF patients is multifactorial including - low cardiac output state, volume expansion, impaired free water excretion due to renal insufficiency and use of loop diuretics. It is generally thought that with restoration of hemodynamics hyponatremia would resolve after LVAD implantation. We sought to determine the etiology of persistent hyponatremia after LVAD implantation. Methods We performed a retrospective analysis of patients with end-stage HF who received a continuous-flow LVAD and subsequently underwent right heart catheterization (RHC) to assess invasive hemodynamics and for speed optimization. Data was collected concurrently on invasive hemodynamics, medication usage and basic metabolic panel. Hyponatremia was defined as serum sodium level 12 mmHg, volume depletion defined by RAP 0.75 (moderate) and >1.0 (severe), partially unloaded left ventricle (LV) defined by PCWP > 15, use of angiotensin converter enzyme inhibitors (ACEI) or angiotensin receptor blockers (ARB), use of loop diuretics and renal function measured by estimated glomerular filtration rate (GFR). Each of the factors were compared between patients with hyponatremia and normal sodium levels. Results We included 143 patients in our study. RHC was performed within 6 months from LVAD implantation in 70% of the population, the median time was 199 days. Patients with hyponatremia had a mean sodium of 130.5 mEq/L compared to 139.8 mEq/L in patients with normonatremia, p-value table 1 ). One-year mortality and all-cause readmissions (from time of RHC) were both higher in the hyponatremia group, p-values of 0.012 and 0.023 respectively. Discussion Persistent hyponatremia after LVAD implantation does not appear to be related to low cardiac output state, volume expansion or depletion, RV dysfunction, use of ACEI or ARBs, loop diuretics or renal function. Hyponatremia may be an independent marker of adverse outcomes after LVAD implantation.
Reducing Risk for Gestational Diabetes Mellitus (GDM) Through a Preconception Counseling Program for American Indian/Alaska Native Girls: Perceptions From Women With Type 2 Diabetes or a History of GDM.

PurposeAmerican Indian and Alaska Native (AIAN) women are disproportionately affected by gestational diabetes mellitus (GDM). GDM is a risk factor for subsequent diagnosis of type 2 diabetes (T2D) ...
Effect of carbon dioxide pneumoperitomeum during laparoscopic pyloromyotomy

Objective To investigate the effect of carbon dioxide pneumoperitomeum on children 's respiration and circulation during laparoscopic pyloromyotomy.Methods Twenty patients who underwent laparoscopic pyloromyotomy were studied.The respiration and circulation indices were measured on each patient at certain intervals.Results Ten to twenty minutes after the establishment of pneumoperitoneum,the tidal volume declined.The volume was significantly lower than that 5 minutes after reversal of pneumoperitoneum(P＜0.05).Pet CO2 was significantly higher than the pre-pneumoperitoneum value(P＜0.05).Five minutes after the withdraw pneumoperitoneum,PetCO2 dedined slightly yet it was still significantly higher than the pre-pneumoperitoneum value(P＜0.05).The diastolic blood pressure,systolic blood pressure,mean arterial pressure,oxygen saturation,heart rate,air way peak pressure and lung compliance were all deranged but the changes were not significant compared to the pre-pneumoperitoneum values.Conclusions Carbon dioxide pneumoperitomeum can affect the tidal volume and PetCO2 in neonates and infants.Being aware of these changes is crucial to minimizing untoward effects in the laparoscopic surgeries in neonate and young infants. Key words: Pneumoperitoneum,artificial; Laparoscopic surgical procedures; Blood gas analysis
Rural Nonagricultural/Nonfarm Sector in the International Development Studies Literature

This chapter reviews the literature on the development of the rural nonfarm sector (RNFS) globally. The first section looks at the different ways in which the RNFS and rural nonfarm employment (RNFE) are looked at in terms of their conceptual definitions. The second section reviews the origin and determinants of the RNFS, focusing on its growth linkages to other sectors of the economy, the role of the state in its development and the impact of neoliberal globalization on its growth and development. The third section examines the literature on the development outcomes of the RNFS in recent times. The fourth section highlights the literature on the RNFS in Kerala from the point of view of rural industrialization and the coir industry. The chapter ends with a conclusion.
Persistent Astrometric Deflections from Gravitational-Wave Memory.

Gravitational waves (GWs) produce small distortions in the observable distribution of stars in the sky. We describe the characteristic pattern of astrometric deflections created by a specific gravitational waveform called a burst with memory. Memory is a permanent, residual distortion of space left in the wake of GWs. We demonstrate that the astrometric effects of GW memory are qualitatively distinct from those of more broadly considered, oscillatory GWs---distinct in ways with potentially far-reaching observational implications. We discuss some such implications pertaining to the random-walk development of memory-induced deflection signatures over cosmological time spans and how those may influence observations of the cosmic microwave background.
Novel pharmacotherapies for heart failure

Abstract In this chapter, we summarize the pharmacological treatment of heart failure (HF), a heterogeneous clinical syndrome with complex pathophysiology that, in most cases, ultimately results from left ventricular (LV) remodeling and systolic and/or diastolic dysfunction of the heart. The primary focus of the review is recently approved and emerging pharmacotherapies; guideline directed medical therapy (GDMT) is also briefly discussed. The pharmacologic management of heart failure can be challenging due its underlying heterogeneity and variability in disease trajectory. Currently, neurohormonal blocking agents are the mainstay of GDMT in HF with reduced ejection fraction (HFrEF, LVEF
Many-body theory of radiative lifetimes of exciton-trion superposition states in doped two-dimensional materials

Optical absorption and emission spectra of doped two-dimensional (2D) materials exhibit sharp peaks that are often mistakenly identified with pure excitons and pure trions (or charged excitons), but both peaks have been recently attributed to superpositions of two-body exciton and four-body trion states and correspond to the approximate energy eigenstates in doped 2D materials. In this paper, we present the radiative lifetimes of these exciton-trion superposition energy eigenstates using a many-body formalism that is appropriate given the many-body nature of the strongly coupled exciton and trion states in doped 2D materials. Whereas the exciton component of these superposition eigenstates are optically coupled to the material ground state and can emit a photon and decay into the material ground state provided the momentum of the eigenstate is within the light cone, the trion component is optically coupled only to the excited states of the material and can emit a photon even when the momentum of the eigenstate is outside the light cone. In an electron-doped 2D material, when a four-body trion state with momentum outside the light cone recombines radiatively, and a photon is emitted with a momentum inside the light cone, the excess momentum is taken by an electron-hole pair left behind in the conduction band. The radiative lifetimes of the exciton-trion superposition states with momenta inside the light cone are found to be in the few hundred femtoseconds to a few picoseconds range and are strong functions of the doping density. The radiative lifetimes of exciton-trion superposition states with momenta outside the light cone are in the few hundred picoseconds to a few nanoseconds range and are again strongly dependent on the doping density. The doping density dependence of the radiative lifetimes of the two peaks in the optical emission spectra follows the doping density dependence of the spectral weights of the same two peaks observed in the optical absorption spectra, as both have their origins in the Coulomb coupling between the excitons and trions in doped 2D materials.
Prospective associations of e-cigarette use with cigarette, alcohol, marijuana, and nonmedical prescription drug use among US adolescents.

Abstract Background As e-cigarette use continues to increase in the U.S., research is needed to understand its prospective risk for cigarette smoking and other substance use in young adulthood, including alcohol, marijuana, and nonmedical prescription drugs (NMPDs). Methods This study used data from the Monitoring the Future (MTF) study a nationally representative annual survey of 12th graders (modal age 18) in the US. The analytic sample included 2014–2016 MTF cohorts that were selected and completed follow up one year later (modal age 19; n = 717). Using logistic regression, we examined cross-sectional and prospective associations of past 30-day e-cigarette use with past 30-day cigarette, alcohol, marijuana, and NMPD use. We examined prospective associations among the full sample and associations with incidence of each of these substances among those who reported no history of use in 12th grade. Results In cross-sectional analysis, those who reported past 30-day e-cigarette use at age 18 were more likely to report past 30-day cigarette use, alcohol use, marijuana use, and NMPD use at age 19. In multivariable longitudinal analysis, past 30-day e-cigarette users at age 18 were more likely to report past 30-day cigarette, marijuana, and NMPD use at age 19, including e-cigarette users who had no history of using these substances at age 18. Conclusions This study suggests that e-cigarette use may be an indicator of future substance use risk in young adulthood. Adolescent e-cigarette users may benefit from secondary prevention efforts to mitigate this risk.
The COVID-19 Diaries: Identity, Teaching, and Learning at a Crossroads

Despite the fact that American education has at its core strived to provide pathways of opportunity to remedy socio-economic inequalities, as educational institutions transitioned into online virtual classrooms due to the COVID-19 pandemic these inequalities have come into sharper focus for us During the process of engaging in a larger self-study, we became more aware of the stark socio-economic disparities of our students in a virtual space, specifically amongst students of color, and how these disparities affected learning outcomes and their identity Juxta positioning the situated in-between spaces of in-class and virtual environments our identities as educators were fluid and intersectional, negotiated in response to student interactions thereby enabling changes in our Dialogical Selves The sample for this study consisted of 2 faculty members and 40 students Data sources included reflexive journals, recorded class sessions, students' questionnaires, and artifacts such as student feedback collected through “exit tickets” as well as recorded meetings Some findings include (1) students' identities were negotiated differently in face to face classrooms vs virtual classrooms, (2) fluidity in intersectional identity due to intersections of I-positions in the dialogical self, and (3) acknowledging and accepting the presence of COVID-19 created a sense of community in the virtual classroom (4) incorporating self-care and caring pedagogical practices provided an empowering space for students and educators © Copyright © 2020 Sequeira and Dacey
Pleasure in parenting as a mediator between fathers' attachment representations and paternal sensitivity.

The present study examined the mediating role of pleasure in parenting in the link between fathers' attachment representations and paternal sensitivity among 138 father-infant dyads from a rural part of the southeastern United States. First-time fathers' attachment representations were assessed using the Adult Attachment Interview (AAI) prenatally. Pleasure in parenting-a multidimensional construct assessing positive attitudes and beliefs toward the parenting role-was coded from fathers' interviews at 3 months. Paternal sensitivity was coded from father-infant play interactions at 12 months. Results indicated that fathers with secure-autonomous adult attachment representations showed more pleasure in parenting. In turn, fathers who took more pleasure in parenting also interacted more sensitively during father-infant interactions. Moreover, although the direct association between fathers' attachment representations and sensitivity was nonsignificant, the indirect effect from secure-autonomous representations to sensitivity via pleasure in parenting was significant. Findings suggest that first-time fathers' parenting attitudes may play a role in transmitting representations of early caregiving experiences to sensitive interactions with their own infants. (PsycInfo Database Record (c) 2021 APA, all rights reserved).
Patients with Diabetes Mellitus Experience Poorer Outcomes After Arthroscopic Rotator Cuff Repair

Abstract Hypothesis/Purpose The purpose of this study was to identify potential differences using validated clinical outcome instruments between patients with and without DM afterarthroscopic RCR. Methods Six-hundred eighty-four patients (32 with and 652 without DM) who underwent arthroscopic RCR were prospectively followed using the visual analog pain scale (VAS), Simple Shoulder Test (SST), Single Assessment Numeric Evaluation (SANE), American Shoulder and Elbow Surgeons (ASES), and Veterans RAND 12-item (VR-12) Health Survey (mental and physical component scores) preoperatively and at 3, 6, 12, and 24 months postoperatively. Results Patients with DM experienced significantly more pain (p = 0.0172) and had lower SST (p = 0.0458) and ASES (p = 0.0200) scores than patients without DM 6 months after surgery. While differences between groups are seen at other postoperative timepoints none are statistically significant. They also exhibited lower self-rated mental health status at 12 months (p = 0.0034) and 24 months (p = 0.0077), as well as lower self-rated physical health status at 12 months (p = 0.0223) and 24 months (p = 0.0077). Changes in scores from pre- to postoperatively were not different for patients with DM versus without DM. Conclusion Patients with DM experience significantly more pain, exhibit significantly poorer shoulder function, and report persistently diminished mental and physical health status compared with their counterparts without DM after undergoing arthroscopic RCR. While these differences did not reach the minimal clinically important difference, orthopedic surgeons should be cognizant of DM as an outcome-modifying variable when selecting, counseling, and treating patients with rotator cuff tears. Glycemic control should be scrutinized and optimized during the perioperative medical evaluation and ultimately factored into the surgical risk profile and prognosis.
Self-collimating surface acoustic waves on multilayer structures

There has been growing interest in recent years over the investigation of bulk acoustic waves (BAW) which propagate along certain directions in anisotropic crystals with a minimum of diffraction. One application of these BAWs is for multichannel acousto-optic devices. The fact that the beams propagate with the minimum diffraction implies that the channels in such a device can be closely packed. In this paper we present a methodology whereby self-collimating surface acoustic waves (SAW) can be engineered on surfaces where the substrate itself does not exhibit this behavior. We discuss the specific case of a ZnO layer on (001)-cut -propagating GaAs for which a fair amount of slowness surface data exists. Finally, using angular spectrum of plane waves (ASPW) diffraction theory we present beam propagation data which substantiates the claim that the beam on such a multilayer structure can propagate without changing its shape.
Encrypted Database Integrity in Database Service Provider Model

In the database service provider model, a service provider hosts client’s data and allows access to data via a database language such as SQL. Database service provider model offers considerable benefits to organizations with data management needs. Yet, the model introduces many significant challenges, in particular that of data privacy and security. Ensuring the integrity of the database, which is hosted by a service provider, is a critical and challenging problem in this context. We propose an encrypted database integrity scheme, which allows the owner of the data to ensure the integrity of the database hosted at the service provider site, in addition to security of the stored data against malicious attacks.
Thermal performance measurements of a graphite tube compact cryogenic support for the Superconducting Super Collider

The magnet cryostat development program for the Superconducting Super Collider (SSC) High Energy Physics Proton-Proton Collider has produced an innovative design for the structural support of the cold mass and thermal radiation shields. This work updates the continuing development of the support known as the Compact Cryogenic Support (CCS). As the structural and thermal requirements of the SSC became better defined, a CCS was developed that employs an innermost tube comprised of a graphite composite material. Presented is the thermal performance to 4.5K of the graphite CCS model. 8 refs., 6 figs., 2 tabs.
Ischemic dilatation of the colon

Ischemic colitis may present as dilatation of the colon, often seen in acute ulcerative colitis. Clinical history and radiographic findings usually suffice to differentiate these two lesions. Prompt surgical treatment is indicated for ischemic dilatation. Two cases are presented to show that ischemic colitis may progress to transmural gangrene, without striking clinical change. Repeated barium enema and plain abdominal films are required for the management of patients with ischemic colitis, who do not promptly recover. The progression from thumb printing to ulcerative and pseudopolypoid changes on barium enema, or the development of dilatation in a segment of ischemic colon, indicates necrosis and requires immediate surgical treatment.
Economic Growth, Distribution and Incomes of the Poor

We question whether increasing inequality accompanies growth in LDCs. Most cross‐section studies claim that it does. Our fourteen LDC cross‐section is similar to others, but changes over time in these LDCs do not indicate increased inequality with growth.
Direct measurement of exchange as a function of separation for discrete donor-acceptor pairs in ZnSe.

We describe optical detection of magnetic resonance for 17 well-resolved discrete zinc interstitial donor-zinc vacancy acceptor pairs of varying separation in ZnSe. For most of the pairs, microwave transitions are detected between the exchange split triplet and singlet manifolds giving a direct high-precision measurement of the separated electron and hole exchange interaction in the excited emitting state of each pair. From these studies the E(+/2+) second donor state of the isolated interstitial zinc atom is estimated to be \ensuremath{\sim}${E}_{c}$-0.8 eV.
HDAC-mediated suppression of histone turnover promotes epigenetic stability of heterochromatin.

The mechanisms underlying gene silencing and epigenetic stability of heterochromatin are not fully understood. New studies in fission yeast now show that heterochromatin differs from euchromatin in the turnover of histones, and they identify the histone deacetylase Clr3 as a factor that inhibits histone turnover across heterochromatin domains and is crucial for the stable inheritance of heterochromatin in cis.
High Vegetable and Fruit Diet Intervention in Premenopausal Women with Cervical Intraepithelial Neoplasia

Abstract Objective To examine whether diet intervention can promote increased vegetable and fruit intake, as reflected in increased plasma carotenoid and decreased plasma total homocysteine concentrations, in premenopausal women with cervical intraepithelial neoplasia, a precancerous condition. Design Randomized controlled diet intervention study. Subjects Fifty-three free-living premenopausal women who had been diagnosed with cervical intraepithelial neoplasia, were randomly assigned to an intervention (n=27) or a control (n=26) group. Intervention Individualized dietary counseling to increase vegetable and fruit intake. Main outcome measures Diet was assessed by food frequency questionnaire. Plasma carotenoids and total homocysteine were measured at enrollment and at 6 months follow up. Analysis Associations between baseline plasma concentrations of carotenoids and homocysteine and influencing factors were examined with multiple regression analysis. Repeated measures analysis of variance was used to test for group by time effects in these plasma concentrations. Plasma carotenoids at baseline and 6 months in the study groups, and differences in homocysteine concentrations from baseline to 6 months, were compared with independent sample t tests. Results Repeated measures analysis of variance showed significant group by time effects ( P P Applications Individualized dietary counseling can effectively promote increased vegetable and fruit intake in premenopausal women. This dietary pattern may reduce risk for cancer and other chronic diseases and also promote an improvement in folate status. J Am Diet Assoc. 2001:101;1167–1174 .
Quantification of Bax and Bcl2 in polymorphonuclear leukocytes from haemodialysis patients: relation to hydrogen peroxide.

Background Bax and Bcl2 are two apoptosis-related molecules that play an important role in determining cell fate following oxidative injury. In the present study, we explored the relation of hydrogen peroxide (H 2 O 2 ) generation by polymorphonuclear cells (PMNs) to the cytosolic expression of Bax and Bcl2 proteins and apoptosis in haemodialysis (HD) patients. Methods Cytosolic generation of H 2 O 2 by PMNs from control subjects and HD patients was measured by flow cytometry using the dichlorofluorescin diacetate assay. Bax and Bcl2 expression was detected by flow cytometry using FITC-conjugated antibodies. Apoptosis was quantified by flow cytometry using propidium iodide nuclear staining. To examine the effect of H 2 O 2 on Bcl2 and Bax expression, PMNs from control subjects were briefly exposed to H 2 O 2 (0.1-100 μM) for 10 min and then washed and cultured for 6 h, with or without catalase, a H 2 O 2 detoxifying molecule. Bcl2 and Bax expression was determined by Western blot analysis. Results Basal H 2 O 2 generation by resting PMNs was significantly higher in HD patients compared with control subjects (211 ± 115 vs. 23 ± 5 MFI; P = 0.002). However, PMNs from HD patients did not undergo accelerated programmed cell death compared with control subjects (58 ± 7% vs. 46 ± 5; P = 0.14). Polymorphonuclear cells cytosolic Bcl2 was undetected in control subjects but detected in 25% of HD patients, and Bax was more frequently detected in PMNs from HD patients (75% vs. 67%; P = 0.04). In the HD patients with detectable cytosolic Bax and Bcl2 proteins, the Bax to Bcl2 ratio inversely correlated with H 2 O 2 levels (P < 0.0001). Finally, brief exposure of PMNs to 0.1-100 μM of H 2 O 2 resulted in a marked increase in Bcl2 expression (P = 0.001), which was prevented by catalase (P = 0.05). There was no apparent effect on Bax expression. Conclusions This study demonstrates that in HD patients, high-resting cytosolic H 2 O 2 production by PMNs is not associated with accelerated in vitro apoptosis, and that the Bax/ Bcl2 system may counter-balance the deleterious effects of reactive oxygen species in human PMNs.
Fluoxetine-induced memory impairment in an adolescent.

ABSTRACT This paper describes a 14-year-old male patient who complained of memory problems during treatment with fluoxetine for major depression. The patient showed impairments on all five scales of the Wechsler Memory Scale-Revised during fluoxetine treatment. Three of the scales, Verbal Memory, Visual Memory, and General Memory, showed statistically significant improvements after fluoxetine was discontinued. This case represents the first time memory deficits related to fluoxetine were quantitated with a standardized memory test. It points to cognitive side effects that need to be understood. J. Am. Acad. Child Adolesc. Psychiatry, 1994, 33, 9:1303–1306.
Two-dimensional NMR studies of 2-substituted thioxanthene sulfoxides

2-Fluoro-, 2-chloro-, 2-bromo-, 2-methyl-, and 2-methoxythioxanthene have been prepared by borane reduction of the corresponding thioxanthone. The corresponding sulfoxides were prepared by m-chloroperoxybenzoic acid oxidation of these sulfides. Proton and carbon chemical shifts have been assigned to these thioxanthene sulfoxides with the aid of LROCSCM and SROCSCM experiments. Carbon chemical shifts in the unsubstituted rings occur at approximately 125 ppm (C5); 128 ppm (C6); 130 ppm (C7); 128 ppm (C8); and 36 ppm (C9). The methylene protons appears as AB doublets at approximately 4.2 and 3.8 ppm. All sulfoxides have the same, pseudo-equatorial geometry.
More precise tables of optimal balanced 2m fractional factorial designs of srivastava and chopra, 7≤m≤10

Abstract We present revised tables of optimal balanced 2 m fractional factorial designs of resolution V for 7≤ m ≤10. The revision consists in a correction of previous errors and an increased precision of calculation.
Favorable Response to High-Dose Infliximab for Refractory Childhood Uveitis

Objective Uveitis in children most commonly is associated with juvenile idiopathic arthritis. In addition to topical glucocorticoids, treatment may include systemic immunosuppressive agents. Tumor necrosis factor α (TNF-α) has been implicated in the pathogenesis of uveitis; therefore, TNF-α blockade seems to be a reasonable therapeutic option to investigate. We report successful treatment of children with uveitis using infliximab. Study Design A retrospective study of our complete experience using infliximab for the treatment of childhood uveitis was conducted. Participants Seventeen children (14 females, 3 males) with chronic uveitis were administered high-dose infliximab (10–20 mg/kg/dose). Main Outcome Measures Our main outcome measure was the ability to eliminate all signs of intraocular inflammation. Results All 17 patients demonstrated a dramatic, rapid response, with no observed inflammation in 13 patients after the second infusion, and 4 patients requiring 3 to 7 infusions to achieve disease quiescence. Additional immunosuppressives and topical glucocorticoids were tapered when patients achieved no intraocular inflammation. Conclusions In this series, high-dose infliximab was a rapidly effective, well-tolerated therapeutic agent for the treatment of chronic, medically refractory, noninfectious uveitis.
ESR study of two phases of di[bis(ethylenedithio)tetrathiafulvalene]triiodide [(BEDT-TTF ) 2 I 3 ]

The sulfur-based organic metal di[bis(ethylenedithio)tetrathiafulvalene]triiodide [or (BEDT-TTF${)}_{2}$${\mathrm{I}}_{3}$, abbreviated (ET${)}_{2}$${\mathrm{I}}_{3}$] occurs in at least two crystalline phases. One phase (denoted as \ensuremath{\beta}) exhibits ambient-pressure superconductivity, while the second (denoted \ensuremath{\alpha}) is characterized by an abrupt decrease in conductivity below 135 K. Electron-spin-resonance data are reported for both phases. The spin susceptibility of the superconducting \ensuremath{\beta} phase is constant below 100 K as expected for a metal, while that of the \ensuremath{\alpha} phase decreases by nearly 2 orders of magnitude below 136 K. The microwave conductivity of the \ensuremath{\beta} phase agrees with the published dc conductivity. The superconducting transition temperature, ${T}_{c}$, and its pressure dependence are reported for \ensuremath{\beta}-[(ET${)}_{2}$${\mathrm{I}}_{3}$].
Goldilocks Meets Santa Rosalia: An Ephemeral Speciation Model Explains Patterns of Diversification Across Time Scales.

Understanding the rate at which new species form is a key question in studying the evolution of life on earth. Here we review our current understanding of speciation rates, focusing on studies based on the fossil record, phylogenies, and mathematical models. We find that speciation rates estimated from these different studies can be dramatically different: some studies find that new species form quickly and often, while others find that new species form much less frequently. We suggest that instead of being contradictory, differences in speciation rates across different scales can be reconciled by a common model. Under the “ephemeral speciation model”, speciation is very common and very rapid but the new species produced almost never persist. Evolutionary studies should therefore focus on not only the formation but also the persistence of new species.
Laminitic metabolic profile in genetically predisposed ponies involves exaggerated compensated insulin resistance

Twenty years ago Jeffcott and associates proposed a clinical syndrome of laminitis and hyperlipaemia that involved adrenal stress and insulin resistance in ponies predisposed to insulin resistance by a thrifty gene. Our primary purpose was to quantitatively determine a metabolic profile for this clinical syndrome. An inbred herd of 170 ponies had no clinical cases of laminitis in March, 2004, but 13 active cases developed at the end of May and were studied on day 1 or 2 of initial diagnosis. This was based on hesitant gait, posture, hoof temperature and bouncing digital pulse. All 13 cases of clinical laminitis (CL) developed in a group of 54 ponies that had previously been positive for laminitis (PL), while no cases developed (p < 0.0001) in the remaining 116 ponies that had never exhibited laminitis (NL). This result established the predictive value of a pre-laminitic metabolic syndrome in apparently healthy ponies, which is a phenotypic representation of a genotype characterized as dominance with partial suppression that may be amenable to nutritional intervention. The advent of clinical laminitis occurred at the same time as an 83% increase (p = 0.039) of starch in the pasture, which was attributable to a rich growth of clover. Ponies were gathered, weighed, scored for body condition, and sampled for blood between 08:00 and 10:00 hours. Body condition scores were higher (p = 0.002) in the CL and PL groups (6.5 ± 0.1) than the NL (6.1 ± 0.1). Plasma analysis revealed higher (p < 0.001) concentrations of insulin in the affected group (92 ± 2, 32 ± 6 and 15 ± 2 μIU/ml in CL, PL and NL respectively) and triglycerides (58 ± 6, 44 ± 4, and 44 ± 4 mg/dl), but no differences were found for glucose, non-esterified fatty acids, and cortisol. Plasma insulin and glucose concentrations were applied as proxies that indicate low insulin sensitivity and extremely high pancreatic β-cell response, together indicating a transition state between compensated and uncompensated insulin resistance in the CL group that might be regarded as exaggerated compensation. For comparison, in two cases of subacute laminitis studies on the 8th day of the disease, insulin resistance was uncompensated. The effectiveness of the extreme pancreatic response in the prodromal stage is also indicated by the lack of hyperglycaemia and only mild elevation of serum triglycerides. Absence of hypercortisolaemia suggests that affected ponies were not undergoing adrenal stress. Collectively these results indicate a changing role of insulin resistance in laminitis: a compensated predisposing factor in healthy but genetically predisposed ponies, then a pathogenetic component as a transient exaggerated compensation during the advent of laminitis, and finally uncompensated insulin resistance later in the course of the disease.
Global Capitalism and Commodity Chains: Looking Back, Going Forward

This paper assesses the achievements and limitations of commodity chain research as it has evolved over the last decade. The primary objectives are two-fold. First, I highlight an important but generally unacknowledged break between the original world-systemsinspired tradition of commodity chain research and two subsequent chain approaches, the global commodity chain (GCC) and global value chain (GVC) frameworks. Second, I argue that contra the macro and holistic perspective of the world-systems approach, much of the recent chains literature, and particularly the more economistic GVC variant, is increasingly oriented in its analytical approach towards the meso level of sectoral logics and the micro level objective of industrial upgrading. I conclude that closer attention to the larger institutional and structural environments in which commodity chains are embedded is needed in order to more fully inform our understanding of the uneven social and developmental dynamics of contemporary capitalism at the global-local nexus.
Cold Chemical Oxidation of Proteins

Various methods of protein footprinting use hydrogen peroxide as oxidant. Its removal by various solid-phase desalting methods, catalase treatment, or freeze-drying after the footprinting is critical to insure no uncontrolled oxidation. Although catalase treatment removes hydrogen peroxide with little loss of protein or additional protein oxidation, we discovered that freeze-drying or freezing of the protein in peroxide solution does lead to protein oxidation. Interestingly, the oxidation is not a result of freeze or thaw processes but depends on the temperature and length of time for incubation. After 2 h, apomyoglobin undergoes nearly complete single oxidation at −80 °C and double oxidation at −15 °C. The oxidation extents are in addition to the number of methionine residues. Minimal oxidation is observed at 4 °C and 22 °C compared to oxidation at −80 °C or −20 °C. The concentration of hydrogen peroxide is critical; 75 mM (0.2%) is required to oxidize > 50% of the protein at −15 °C and 100-mM (0.3%) at −80 °C. In addition to Met, ~ 5% of the tryptophan and tyrosine residues are oxidized as well as lower amounts of His and Phe. Oxidation of Val 68 and Val 17 (a buried residue) also occurs, with the oxidation of Val 17 likely occurring by electron transfer from one of two of the oxidized aromatic residues contacting Val 17. We describe here the need to remove the hydrogen peroxide prior to cold storage of proteins, and we also report some preliminary results pertaining to the mechanism of cold, solid-state oxidation.
Teaching Formal Proposals: A Versatile Minicourse in Technical Writing

Because in these days of economic troubles, all areas of science, social science, and industry must account for and justify more closely what they do and want to do, students of technical writing w...
Thermally-Aware Design

With greater integration, the power dissipation in integrated circuits has begun to outpace the ability of today's heat sinks to limit the on-chip temperature. As a result, thermal issues have come to the forefront, and thermally aware design techniques are likely to play a major role in the future. While improved heat sink technologies are available, economic considerations restrict them from being widely deployed until and unless they become more cost-effective. Low power design is helpful in controlling on-chip temperatures, but is already widely utilized, and new thermal-specific approaches are necessary. In short, the onus on thermal management is beginning to move from the package designer toward the chip designer. This survey provides an overview of analysis and optimization techniques for thermally aware design. After beginning with a motivation for the problem and trends seen in the semiconductor industry, the survey presents a description of techniques for on-chip thermal analysis. Next, the effects of elevated temperatures on on-chip performance metrics are analyzed. Finally, a set of thermal optimization techniques, for controlling on-chip temperatures and limiting the level to which they degrade circuit performance, are described.
Pressure profile of the rectum and anus of healthy persons.

This study was undertaken to determine the pressure profile of the rectum and anal sphincter of healthy persons. Open-tip tubes and tiny balloons of various sizes connected to pressure transducers were withdrawn in stages from the lower part of the sigmoid to the exterior in 11 healthy males in the Sims position. Records of the pressures encountered during the withdrawals were made photokymographically. Mean sigmoid and rectal resting pressures were 2 to 5 cm. of water above ambient pressure. A band of elevated pressure about 4 cm. in width was always detected in the anal sphincter. The mean maximal pressure in the sphincter as detected by open-tip tubes was 45 cm. of water; greater maximal pressures were encountered when balloons were withdrawn through the sphincter. Bands or zones of increased pressure were consistently detected in the rectum during withdrawal of even tiny balloons. These zones have been interpreted as being produced by pressure applied to the balloon as it was withdrawn past a bend in the rectum or over folds in the rectum. The suggestion is made that these structures may act as incomplete or feeble valves resisting the analward movement of rectal contents, just as they resisted the analward movement of the balloons.
A POTENT INHIBITOR OF NEURITE OUTGROWTH THAT PREDOMINATES IN THE EXTRACELLULAR MATRIX OF REACTIVE ASTROCYTES

Abstract In a model of astrogliosis in vitro, cultured cortical astrocytes were triggered into a functionally reactive state by an immobilized fragment of the β-amyloid peptide. Induced astrocytes produced an extracellular matrix that inhibited the outgrowth of embryonic CNS axons. Within the extracellular matrix deposited by reactive astrocytes, we found an overall increase in the deposition of chondroitin sulphate that accounted for the inhibition. Specifically, we have detected an increased biosynthesis of a small chondroitin/heparan sulphate proteoglycan that is a potent inhibitor of axon outgrowth. We further suggest that this proteoglycan, or related molecules yet to be discovered, may play a role in gliosis-mediated regenerative failure of CNS axons. Copyright © 1996 ISDN.
Participant reactions to a computerized telephone system for nutrition and exercise counseling.

This paper reports on an evaluation of the reactions of participants in a computer-controlled telephone conversation system (telephone-linked care, TLC) designed to offer nutrition and exercise counseling. After 6 months in the study, subjects were asked a series of questions about their opinions of the TLC system, including overall satisfaction and the system's helpfulness. One hundred and ninety individuals completed the attitude survey. On a scale of 0-100, respondents rated the overall satisfaction and helpfulness of the system at 63.6 and 62.3. Subjects using the nutrition counseling version of TLC rated it significantly higher on satisfaction (73.0 versus 52.4) and helpfulness (70.3 versus 53.7) than did subjects using the exercise version. Satisfaction and helpfulness were correlated with perceived usability, amount of contact, realism, and credibility (P < 0.01). Multivariate analyses showed that treatment group and number of calls made accounted for the greatest amount of variance in ratings of satisfaction and helpfulness. The findings suggest that the amount of contact with this technology, reflected by the number of calls, and the treatment group, nutrition or exercise, were significant predictors of reported satisfaction and perceived helpfulness of the system.
Flow and heat transfer simulation of injection molding with microstructures

Injection molding has been used for mass production of polymer products with microstructures. Conventional Hele-Shaw 2.5D midplane simulation is unable to describe the flow pattern correctly. It tends to over-predict the effects of microstructures on global flow patterns. For the unidirectional flow, an x-z planar based on the general momentum equation is able to achieve better accuracy and to retrieve more detailed flow and heat transfer information around the microstructures. A hybrid numerical technique is developed, which can significantly reduce the nodes and computation time, and yet provide good flow simulation around the microstructures. The mold-melt heat transfer coefficient and injection speed are shown to be very important factors in determining the filling depth in microstructures. A decrease of the heat transfer coefficient and the occurrence of wall-slip are likely in microchannels. Polym. Eng. Sci. 44:1866–1876, 2004. © 2004 Society of Plastics Engineers.
Gadolinium-Loaded Viral Capsids as Magnetic Resonance Imaging Contrast Agents.

Polymeric nanohybrid P22 virus capsids were used as templates for high density Gd3+ loading to explore magnetic field-dependent (0.5–7.0 T) proton relaxivity. The field-dependence of relaxivity by the spatially constrained Gd3+ in the capsids was similar when either the loading of the capsids or the concentration of capsids was varied. The ionic longitudinal relaxivity, r 1, decreased from 25–32 mM−1 s−1 at 0.5 T to 6–10 mM−1 s−1 at 7 T. The ionic transverse relaxivity, r 2, increased from 28–37 mM−1 s−1 at 0.5 T to 39–50 mM−1 s−1 at 7 T. The r 2/r 1 ratio increased linearly with increasing magnetic field from about 1 at 0.5 T, which is typical of T 1 contrast agents, to 5–8 at 7 T, which is approaching the ratios for T 2 contrast agents. Increases in electron paramagnetic resonance line widths at 80 and 150 K and higher microwave powers required for signal saturation indicate enhanced Gd3+ electron spin relaxation rates for the Gd3+-loaded capsids than for low concentration Gd3+. The largest r 2/r 1 at 7 T was for the highest cage loading, which suggests that Gd3+–Gd3+ interactions within the capsid enhance r 2 more than r 1.
A Principle-Attribute Matrix for Environmentally Sustainable Management Education and Its Application: The Case for Change-Oriented Service-Learning Projects

The environmental threats humanity faces have led businesses to increasingly commit to improve their environmental performance and to increasing attempts to address environmental issues in management education. This article presents a matrix of (a) principles that can underlie and (b) attributes that can be generated by environmentally focused management education and uses the matrix to identify topics, assignments, and assessment mechanisms that can be incorporated into environmental management education. Particular focus is given to skills related to facilitating organizational change. Environmental change—related course projects are suggested as particularly helpful in the development of these attributes, and use of service learning applied to campus sustainability issues is suggested as offering significant opportunities for engaging students in change-oriented projects. Observations related to implementing such projects based on the author's experience with them are offered. The article's concepts an...
Structural and Electronic Properties of Negative Electron Affinity Epitaxial Diamond (110) Films Studied Using Atomic Resolution UHV STM

We report ultrahigh vacuum (UHV) scanning tunneling microscopy (STM) studies of the structural and electronic properties of epitaxial diamond (110) films. We observe that epitaxial diamond (110) films grow very rough due to striations. The striations are found to be due to the appearance of(111) faces and contain (100) steps. UHV STM atomic resolution images of the diamond (110) films show a (lxi) zigzag structure that measures 1.5 ± 0.1 A × 1.5 ± 0.1 A, in agreement with theoretical predictions for the hydrogen terminated diamond (110) surface. Ultraviolet spectroscopy shows that the epitaxial films have a photoelectric threshold of 5.3 ± 0.1 eV, providing evidence that the films have a negative electron affinity surface.
Linear theory of tearing in a high-β plasma

The linear dispersion relation for a collisionless plasma in a sheared one-dimensional current sheet is calculated with reference to conditions in the daytime magnetopause. Calculations are extended to include plasmas with beta approximately equal to 1. It is found that the tearing mode eigenstructure and temporal growth rate are a sensitive function of the ratios l sub s/l sub G, l sub s/l sub T, and l sub s/l sub n, where l sub s is the shearing length of the magnetic field, l sub G is the gradient scale length, and l sub T is the temperature gradient scale length. In particular, if beta is approximately equal to 1, and l sub s is less than l sub G, l sub n, and l sub T, then the thickness of the layer over which particles are resonantly accelerated by the induction magnetic field is approximately rho, a thermal gyroradius. If the above conditions are not satisfied, plasma gradients may electrostatically stabilize the mode.
Dynamic Centrifuge Testing of Slickensided Shear Surfaces

Movement along preexisting slickensided rupture surfaces in overconsolidated clay and clay shale slopes can represent a critical sliding mechanism during earthquakes. The seismic behavior of preexisting slickensided surfaces in overconsolidated clay was examined by performing dynamic centrifuge model tests of two slickensided sliding block models constructed using Rancho Solano lean clay. Dynamic shear displacements were concentrated along the preformed slickensided surfaces. The peak shear resistances mobilized along the slickensided surfaces during dynamic loading were 90-120% higher than the drained residual strength measured prior to shaking. To accurately predict the displacements of the sliding blocks using Newmark's method, it was necessary to use dynamic strengths that were 37-64% larger than the drained residual strength of the soil. Dynamic loading caused a positive pore pressure response in the soil surrounding the slickensided planes. The postshaking shear strengths were 17-31% higher than those measured prior to shaking.