cssi/SciSciGPT-SciSciNet huggingface dataset:
Papillary Thyroid Carcinoma (PTC) in Children and Adults: Comparison of Initial Presentation and Long-Term Postoperative Outcome in 4432 Patients Consecutively Treated at the Mayo Clinic During Eight Decades (1936–2015)

Contemporary guidelines for managing PTC advise an approach wherein primary tumor and regional metastases (RM) are completely resected at first surgery and radioiodine remnant ablation (RRA) is restricted to high-risk patients, policies our group has long endorsed. To assess our therapeutic efficacy, we studied 190 children and 4242 adults consecutively treated during 1936–2015. Mean follow-up durations for children and adults were 26.9 and 15.2 years, respectively. Bilateral lobar resection was performed in 86% of children and 88% of adults, followed by RRA in 30% of children and 29% of adults; neck nodes were excised in 86% of children and 66% of adults. Tumor recurrence (TR) and cause-specific mortality (CSM) details were taken from a computerized database. Children, when compared to adults, had larger primary tumors which more often were grossly invasive and incompletely resected. At presentation, children, as compared to adults, had more RM and distant metastases (DM). Thirty-year TR rates were no different in children than adults at any site. Thirty-year CSM rates were lower in children than adults (1.1 vs. 4.9%; p = 0.01). Comparing 1936–1975 (THEN) with 1976–2015 (NOW), 30-year CSM rates were similar in MACIS <6 children (p = 0.67) and adults (p = 0.08). However, MACIS <6 children and adults in 1976–2015 had significantly higher recurrence at local and regional, but not at distant, sites. MACIS 6+ adults, NOW, compared to THEN, had lower 30-year CSM rates (30 vs. 47%; p < 0.001), unassociated with decreased TR at any site. Children, despite presenting with more extensive PTC when compared to adults, have postoperative recurrences at similar frequency, typically coexist with DM and die of PTC less often. Since 1976, both children and adults with MACIS <6 PTC have a <1% chance at 30 years of CSM; adults with higher MACIS scores (6 or more) have a 30-year CSM rate of 30%.
Everyday Heroism in Practicing Psychology

Heroism requires acting altruistically in the face of considerable risk. Professions such as psychology are based on working toward a public good and accordingly provide offsetting privileges for t...
Oxygen Scavengers affect Gas Mixture and Color Stability of Master Packed Ground Beef

This study investigated the effect of storage time, display time, oxygen scavengers, and carbon dioxide concentration on master packed ground beef color and package characteristics. Samples were stored at 0.5°C for up to 28 d in 20% CO2/80% N2 and 30% CO2/70% N2. Results indicated that red meat color was maintained for up to 28 d of storage. Nevertheless, a* values (meat redness) decreased during display as storage time increased (p < 0.05). Master packs with 2 types of oxygen scavengers showed comparable total carbon dioxide absorbed. However, differences between oxygen scavengers were noticed in packages that did not include meat. Carbon dioxide significantly decreased by 14 d of storage in packages with oxygen scavengers (p < 0.05), and remained low for the duration of the study. Carbon dioxide absorption by an oxygen scavenger is an important factor when considering the headspace gas and specific oxygen scavenger used in a modified atmosphere packaging system.
Physical Interactions between Stars

Physical arguments are presented to show that two-body, tidal-capture binaries should form in abundance (Nb ~ 103) durings the evolution of globular clusters by the time that core collapse begins. Interactions amongst these binaries and with core single stars will cause ejections from the cluster which pump energy into the system producing a bounce and re-expansion. Detailed numerical Fokker-Planck evolutionary calculations presented here confirm this scenario and indicate that this process is likely to be the dominant energy input for most clusters. During the re-expansion phase rcore ∝ t1/3, rhalf ∝ t2/3 with the core containing several hundred very close binary star systems.
Immigration Restrictions and the Politics of Protection

The chapter discusses two 1835 ordinances passed by the local Council of the British colony of Mauritius. Passed shortly after Britain’s 1833 Slavery Abolition Act, these restrictions initiated the regulation and restriction of immigration within the British Empire. Seen as quite novel in their day, these ordinances employed the rhetoric of “protecting emigrants” to legitimize the new constraints they imposed on free human mobility. Today, when the national ‘logic of constraint’ (Mongia in Comparative Studies in Society and History 49: 384–411, 2007) on human mobility is almost uncontested, the idea that immigration controls protect migrants remains central to the discursive practices concerning ‘human trafficking’.
Translating an Evidence-based Multicomponent Intervention for Older Adults With Dementia and Caregivers.

BACKGROUND AND OBJECTIVES Effective community-based programs to maintain health and well-being of adults with dementia are needed. This article describes the translation, implementation, and effectiveness of a multicomponent exercise plus behavioral/psychosocial intervention (Reducing Disability in Alzheimer's Disease-NorthWest [RDAD-NW]) conducted by staff in regional Area Agencies on Aging (AAAs). RESEARCH DESIGN AND METHODS Staggered multiple baseline design was used; 10 AAAs, 20 case managers, and 255 community-residing persons with dementia (PWDs), and family caregivers were enrolled. RDAD-NW was conducted in-home over 6 weeks with aerobic/endurance, strength, and balance/flexibility exercises, dementia education, training to increase pleasant events, and activator-behavior-consequence problem-solving approach. Outcomes included case manager treatment fidelity, and caregiver/PWD physical activity, restricted activity days, physical functioning, quality of life, and affect. RESULTS RDAD-NW was successfully translated and implemented by AAA agency staff through their usual service provision mechanisms. Staff responded positively and delivered the program with a high degree of fidelity. Caregiver/PWD dyads also responded favorably engaging in both exercise and behavioral/psychosocial portions of the program. A total of 207 dyads (81%) completed the intervention and 140 (55%) completed the 13-month follow-up. PWD physical activity increased significantly pre- to posttreatment (p < .001, ES = .54), and 13 months (p < .01, ES = .21). Quality of life of PWD increased significantly pre- to posttreatment (p < .001, ES = .29); caregiver depression improved pre- to posttreatment (p = .01, ES = -.18). DISCUSSION AND IMPLICATIONS RDAD-NW was successfully translated and implemented by AAA case managers and resulted in increased physical activity and improved behavioral and emotional outcomes of caregiver/PWDs. Results support continued dissemination and implementation of RDAD-NW. CLINICAL TRIALS REGISTRATION NCT01708304.
Particle emissions from fused deposition modeling 3D printers: Evaluation and meta-analysis.

Abstract Fused deposition modeling (FDM) 3D printers, the most popular choice among home hobbyists, have been shown to release volatile organic chemicals (VOCs) and billions of airborne particles per minute, indicating the potential for consumer inhalation exposure and consequent health risks. Publications on FDM 3D printer emissions however, contain large heterogeneity of testing methods and analytical procedures making it difficult to reach overall conclusions for particle characteristics or particle number emission rates across the field. In this publication, data were collected over the printing time from 3D printer emission studies including particle count diameters (PCDs) (nanometers), particle number concentrations (PNCs) (particles/cm3), and particle number emission rates (PNERs) (particles min−1). Despite heterogeneity in methods, the majority of particles released were reported as ultrafine in size (i.e.,
Long-term outcome of using Prosthetic Replacement of Ocular Surface Ecosystem (PROSE) as a drug delivery system for bevacizumab in the treatment of corneal neovascularization.

Abstract Purpose To report the long-term outcome of Prosthetic Replacement of the Ocular Surface Ecosystem (PROSE) for delivery of bevacizumab in the treatment of corneal neovascularization (KNV). Methods Retrospective, non-comparative, interventional case series of 13 sequential patients treated for KNV at the BostonSight between 2006 and 2017. In all cases, PROSE treatment was initiated for management of ocular surface disease and patients wore PROSE consistently on a daily wear basis prior to bevacizumab treatment. Patients applied a drop of 1% preservative free bevacizumab to the reservoir of PROSE device twice daily. Patients continued with daily wear of the device during treatment and afterwards. Results 13 patients (8 female and mean age of 45 years) are included with a mean follow-up of 5.1 years (range 6 months–11 years). Underlying ocular diagnoses included Stevens-Johnson syndrome (7), ocular chronic graft-versus-host disease (2), corneal transplant (2), contact lens-related corneal ulcer and limbal stem cell deficiency (1), and familial dysautonomia (1). Median duration of bevacizumab use was 6 months (range 3 months–10 years). Twelve cases (92%) had regression of KNV and 10 cases (77%) had improved best-corrected visual acuity (BCVA) with treatment. Median BCVA improved from −1.1 (LogMAR) at baseline, to −0.66 at end of bevacizumab treatment, and remained −0.63 at last follow-up (P = 0.047). KNV progressed in one eye after discontinuation of bevacizumab. There were no ophthalmic or systemic complications. Conclusions Topical bevacizumab used in PROSE is effective in treating KNV and improving vision. Long-term follow-up reveals durable response and no complications.
Modeling mafic carbonation efficiency using mafic rock chemistries from Nevada, USA

Abstract Mineral carbonation is one of the many ways that are being actively investigated to sequester point-source carbon dioxide emissions. However, relations between reaction conditions, variations in reactant mineral composition, and carbon sequestration potential are poorly understood. In this study we used reaction path geochemical modeling to evaluate carbon sequestration potential during ex-situ mineral carbonation of ten mafic rock samples from Nevada, USA. Models were run using arbitrary dissolution kinetics at temperatures between 0 and 200 °C. A subset of models were run using true dissolution kinetics. In the models, carbon is sequestered in 5 mineral phases: magnesite, siderite, dolomite, calcite, and dawsonite, with magnesite and dolomite the most abundant. Dawsonite sequesters carbon at T > 150 °C in most of the arbitrary kinetics models but is not a significant carbon sink in the models using true dissolution kinetics. The arbitrary kinetics models resulted in 4.5–13 mol of carbon sequestered per kg of reacted mafic rock. True kinetics models only resulted in 1–2 mol of carbon sequestered, but the models only reacted 12.5 to 15 wt percent of the mafic rock inputs. Product minerals using the arbitrary kinetics model have volumes 150%–470% larger than the reactant volumes, whereas using true kinetics the models have a modest increase. Modeling presented herein confirms several areas of Nevada as having potential for mafic rock carbonation, some of which are located near existing coal- and natural gas-fired power plants. As shown in this study, reaction path modeling is a vital and inexpensive tool to help optimize costs and reaction conditions for ex-situ mafic rock carbonation projects.
Estimating sand bed load in rivers by tracking dunes: a comparison of methods based on bed elevation time series

Abstract. Quantifying bed-load transport is paramount to the effective management of rivers with sand or gravel-dominated bed material. However, a practical and scalable field methodology for reliably estimating bed load remains elusive. A popular approach involves calculating transport from the geometry and celerity of migrating bedforms, extracted from time series of bed elevation profiles (BEPs) acquired using echo sounders. There are various echo sounder sampling methodologies to extract bed elevation profiles. Using two sets of repeat multibeam sonar surveys with high spatiotemporal resolution and coverage, we compute bed load using three field techniques (one actual and two simulated) for acquiring BEPs: repeat multibeam, single-beam, and multiple single-beam sonar. Significant differences in flux arise between repeat multibeam and single-beam sonar. Multibeam and multiple single-beam sonar systems can potentially yield comparable results, but the latter relies on knowledge of bedform geometries and flow that collectively inform optimal beam spacing and sampling rate. These results serve as a guide for design of optimal sampling and for comparing transport estimates from different sonar configurations.
A two-player price impact game

We study the competition of two strategic agents for liquidity in the benchmark portfolio tracking setup of Bank, Soner, Voss (2017), both facing common aggregated temporary and permanent price impact a la Almgren and Chriss (2001). The resulting stochastic linear quadratic differential game with terminal state constraints allows for an explicitly available open-loop Nash equilibrium in feedback form. Our results reveal how the equilibrium strategies of the two players take into account the other agent's trading targets: either in an exploitative intent or by providing liquidity to the competitor, depending on the ratio between temporary and permanent price impact. As a consequence, different behavioral patterns can emerge as optimal in equilibrium. These insights complement existing studies in the literature on predatory trading models examined in the context of optimal portfolio liquidation problems.
The Synergy SPICE – Compact Models

SPICE became the de facto standard Integrated Circuit (IC) design tool due in part to being an open-source software program and incorporating mathematical models for the behavior of the semiconductor devices at the core of ICs. The chosen detail level of the device equations in these models is appropriate for circuit simulation and they are referred to as Compact Models. The robustness of the SPICE solution relies on the interdependency between algorithm and device model; first-working silicon depends on this synergy between solution algorithm and device model integrated in a single tool. This paper sketches an overview of the evolution of transistor models in step with semiconductor technology starting with bipolar and continuing over several generations of MOS processes. Alternate modeling approaches such as Analog Hardware Description Languages (AHDL) and table models, and their role in circuit simulation are described in the latter part of the paper. A glance into the future of compact modeling concludes this paper.
Assaying leukocyte hallmarks during sepsis.

Functional changes in leukocytes isolated from 50-μL samples of peripheral blood from sepsis patients correlate with the patients’ clinical status.
Assessment of Benefit of Advanced Inflammatory Bowel Disease Training: Challenges and Solutions.

Background Advanced inflammatory bowel disease (IBD) fellowships are available for gastroenterologists who wish to increase their expertise in complex IBD. However, little is known about the outcomes of such training. The aims of this study were to assess clinical and academic outcomes following advanced training in IBD. Methods We surveyed gastroenterologists who completed advanced IBD fellowships and compared competency and outcomes to gastroenterologists focusing in IBD who completed gastroenterology training alone. Participants completed a survey via REDCap. Continuous variables were compared using the Wilcoxon rank-sum test. Categorical variables were compared using chi-square or Fisher's exact tests. Results A total of 104 physicians participated in the study. IBD fellowships were completed by 31 physicians (30%), of whom 29 (94%) felt their training was excellent. Management of complicated IBD (84%), research mentoring (74%), and career mentoring (71%) were felt to contribute most highly to professional development. Compared to non-advanced trained physicians, advanced trained physicians expressed higher levels of comfort with management of IBD during pregnancy (P = 0.003), complicated IBD (P = 0.057), and peri-operative IBD (P = 0.057). No significant advantage was detected in academic productivity. Common barriers to participation in IBD fellowships included feeling it was unnecessary (45%) and desire to begin a faculty position (42%). Conclusions This study suggests there may be clinical benefit to advanced IBD training. Importantly, this study identified that there are also unique challenges to the assessment of clinical competency in IBD training. Efforts by the IBD community to establish a registry of advanced trainees and improve competency assessments are needed.
Role of the sperm, oocyte, and embryo in recurrent pregnancy loss

Disorders affecting the sperm, oocyte, or embryo may cause a significant fraction of spontaneous miscarriages and cases of recurrent pregnancy loss (RPL). Altered chromosomal integrity of sperm and oocytes, which is highly dependent of the age of the mother, represents a major cause of miscarriage and in turn RPL. Avoiding transfers of abnormal embryos is possible with preimplantation genetic testing for aneuploidies. Chromosomal anomalies may also be caused by structural rearrangements of one or several chromosomes in either parents, a finding encountered in 12% of couples with RPL, including in those who have had one or several healthy babies. More than 40% of these chromosomal rearrangements are identifiable on regular karyotypes. When abnormal findings are made, preimplantation genetic testing for monogenic disorders allows selection of disease-free embryos. Finally, asymmetric inactivation of the X chromosome has been found more commonly in women with RPL, but no specific treatment is currently available.
Mammary collagen is under reproductive control with implications for breast cancer.

Abstract Mammographically-detected breast density impacts breast cancer risk and progression, and fibrillar collagen is a key component of breast density. However, physiologic factors influencing collagen production in the breast are poorly understood. In female rats, we analyzed gene expression of the most abundantly expressed mammary collagens and collagen-associated proteins across a pregnancy, lactation, and weaning cycle. We identified a triphasic pattern of collagen gene regulation and evidence for reproductive state-dependent composition. An initial phase of collagen deposition occurred during pregnancy, followed by an active phase of collagen suppression during lactation. The third phase of collagen regulation occurred during weaning-induced mammary gland involution, which was characterized by increased collagen deposition. Concomitant changes in collagen protein abundance were confirmed by Masson's trichrome staining, second harmonic generation (SHG) imaging, and mass spectrometry. We observed similar reproductive-state dependent collagen patterns in human breast tissue obtained from premenopausal women. SHG analysis also revealed structural variation in collagen across a reproductive cycle, with higher packing density and more collagen fibers arranged perpendicular to the mammary epithelium in the involuting rat mammary gland compared to nulliparous and lactating glands. Involution was also characterized by high expression of the collagen cross-linking enzyme lysyl oxidase, which was associated with increased levels of cross-linked collagen. Breast cancer relevance is suggested, as we found that breast cancer diagnosed in recently postpartum women displayed gene expression signatures of increased collagen deposition and crosslinking compared to breast cancers diagnosed in age-matched nulliparous women. Using publically available data sets, we found this involution-like, collagen gene signature correlated with poor progression-free survival in breast cancer patients overall and in younger women. In sum, these findings of physiologic collagen regulation in the normal mammary gland may provide insight into normal breast function, the etiology of breast density, and inform breast cancer risk and outcomes.
Evidence for mild sediment Pb contamination affecting leaf-litter decomposition in a lake

Much work has focused on the effects of metal-contaminated sediment on benthic community structure, but effects on ecosystem functions have received far less attention. Decomposition has been widely used as an integrating metric of ecosystem function in lotic systems, but not for lentic ones. We assessed the relationship between low-level sediment lead (Pb) contamination and leaf-litter decomposition in a lentic system. We measured 30-day weight loss in 30 litter-bags that were deployed along a Pb-contamination gradient in a cypress-forested lake. At each deployment site we also quantified macrobenthos abundance, dissolved oxygen, water depth, sediment organic content, sediment silt/clay content, and both total sediment and porewater concentrations of Cd, Cu, Ni, Pb and Zn. Principal components (PC) analysis revealed a negative relationship between Pb concentration and benthic macroinvertebrate abundance, and this covariation dominated the first PC axis (PC1). Subsequent correlation analyses revealed a negative relationship between PC1 and percent leaf-litter loss. Our results indicate that leaf-litter decomposition was related to sediment Pb and benthic macroinvertebrate abundance. They also showed that ecosystem function may be affected even where sediment Pb concentrations are mostly below threshold-effects sediment quality guidelines—a finding with potential implications for sediment risk assessment. Additionally, the litter-bag technique used in this study showed promise as a tool in risk assessments of metal-contaminated sediments in lentic systems.
Introduction: Summaries and Comments

In 2008, Howard Kaplan, sociology series editor for the Springer Press, requested that professor Franks undertake this volume. At that time, the latter’s response was that a handbook in neurosociology would be premature. Sociology was behind other disciplines in embracing neuroscience because anything biological was associated with the radical reductionism of E. O. Wilson’s (1975) position that would have rendered sociology unnecessary. Things are obviously different now, but it has been an uphill battle, however rewarding for these editors. While early usage of the term neurosociology should be credited to Warren TenHouten (Bogen et al. 1972), the trek started in earnest with an issue of Franks’ annual series with the JAI Press (1999) titled Mind, Brains and Society coedited with Thomas S. Smith. At that time, a reviewer wrote that all sociologists ought to read this volume, but that few would. According to our royalty checks, he could not have been more correct. A year later, Jonathan H. Turner came out with his Origins of Human Emotions (2000) that was heavily embellished with biological insights into the development of the Hominin brain processes underlying human emotion.
Purification of erythrocyte dematin (protein 4.9) reveals an endogenous protein kinase that modulates actin-bundling activity.

A partially purified preparation of human erythrocyte protein 4.9, consisting of 48-, 52-, and 55-kilodalton polypeptides, is capable of bundling rabbit muscle actin in vitro (Siegel, D. L., and Branton, D. (1985) J. Cell Biol. 100, 775–785). Purification schemes, peptide mapping, antibody cross-reactivity, and chemical cross-linking techniques show that the 48- and 52-kDa polypeptides are sequence-related phosphorylated components, whereas the 55-kDa polypeptide is not. Purified protein 4.9 (dematin), consisting of 48- and 52-kDa polypeptides, effectively bundles actin in vitro; under similar conditions, the isolated 55-kDa polypeptide does not bundle actin. In fact, when added back to purified dematin, fractions containing the 55-kDa polypeptide can completely abolish dematin's actin-bundling activity. The basis for this inhibitory activity is an endogenous protein kinase that phosporylates both the 48- and 52-kDa isoforms of dematin, thus abolishing dematin's actin-bundling activity (Husain-Chishti, A., Levin, A., and Branton, D. (1988) Nature 334, 718–721). Although the endogenous kinase often co-purifies with the 55-kDa polypeptide, it can be separated from the 55-kDa polypeptide and has the characteristics of a catalytic subunit of a cyclic AMP-dependent protein kinase.
Doctrinal Cycles and the Dual-Crisis of 1979

Though presidential doctrines claim to be broad, forward-looking articulations of national security principles, they are in fact reactive and narrow. They emerge following crises and can subsequently constrain security policy, creating ideal conditions for new crises to emerge. This paper thus argues that in the pursuit of security, presidential doctrines can perpetuate a cycle of instability. Using the Nixon Doctrine as the present case study reveals that the strategy first came as a response to the failure in Vietnam, then rendered the US unable to foresee or manage the events of 1979: the Iranian Revolution and the Soviet invasion of Afghanistan. These crises subsequently forced a wholesale reassessment of security in the form of the Carter Doctrine. In examining this period of US–Middle East relations, the constricting, reactive nature of doctrines and the concomitant cycles of instability become self-evident.
Clinical neonatal brain MRI segmentation using adaptive nonparametric data models and intensity-based Markov priors

This paper presents a Bayesian framework for neonatal brain-tissue segmentation in clinical magnetic resonance (MR) images. This is a challenging task because of the low contrast-to-noise ratio and large variance in both tissue intensities and brain structures, as well as imaging artifacts and partial-volume effects in clinical neonatal scanning. We propose to incorporate a spatially adaptive likelihood model using a data-driven nonparametric statistical technique. The method initially learns an intensity-based prior, relying on the empirical Markov statistics from training data, using fuzzy nonlinear support vector machines (SVM). In an iterative scheme, the models adapt to spatial variations of image intensities via nonparametric density estimation. The method is effective even in the absence of anatomical atlas priors. The implementation, however, can naturally incorporate probabilistic atlas priors and Markov-smoothness priors to impose additional regularity on segmentation. The maximum-a-posteriori (MAP) segmentation is obtained within a graph-cut framework. Cross validation on clinical neonatal brain-MR images demonstrates the efficacy of the proposed method, both qualitatively and quantitatively.
The Escherichia coli DNA polymerase III holoenzyme contains both products of the dnaX gene, tau and gamma, but only tau is essential.

Abstract The replicative polymerase of Escherichia coli, DNA polymerase III, consists of a three-subunit core polymerase plus seven accessory subunits. Of these seven, tau and gamma are products of one replication gene, dnaX. The shorter gamma is created from within the tau reading frame by a programmed ribosomal -1 frameshift over codons 428 and 429 followed by a stop codon in the new frame. Two temperature-sensitive mutations are available in dnaX. The 2016(Ts) mutation altered both tau and gamma by changing codon 118 from glycine to aspartate; the 36(Ts) mutation affected the activity only of tau because it altered codon 601 (from glutamate to lysine). Evidence which indicates that, of these two proteins, only the longer tau is essential includes the following. (i) The 36(Ts) mutation is a temperature-sensitive lethal allele, and overproduction of wild-type gamma cannot restore its growth. (ii) An allele which produced tau only could be substituted for the wild-type chromosomal gene, but a gamma-only allele could not substitute for the wild-type dnaX in the haploid state. Thus, the shorter subunit gamma is not essential, suggesting that tau can be substitute for the usual function(s) of gamma. Consistent with these results, we found that a functional polymerase was assembled from nine pure subunits in the absence of the gamma subunit. However, the possibility that, in cells growing without gamma, proteolysis of tau to form a gamma-like product in amounts below the Western blot (immunoblot) sensitivity level cannot be excluded.
Platinum Germanosilicide Contacts Formed on Strained and Relaxed $\hbox{Si}_{1 - x}\hbox{Ge}_{x}$ Layers

Contact resistivity is a key contributor to the parasitic series resistance of nanoscale MOSFETs. Since the contact resistivity is an exponential function of the Schottky barrier height, new contact materials that can provide smaller barrier heights to source-drain junctions are needed. Platinum germanosilicide (PtSi1-xGex) is of interest as a contact material to the recessed Si1-xGex junctions of p-channel MOSFETs due to the large work function of platinum silicide (PtSi). In this paper, we explore the impact of in-plane biaxial compressive strain in Si1-xGex layers on PtSi1-xGex formation and the impact of the PtSi1-xGex on the strain in Si1-xGex. The parameters considered in this paper include the Ge content, the thickness of the Si1-xGex epitaxial layer, and the PtSi1-xGex thickness. The results show that the resistance, surface morphology, and the crystalline structure of the PtSi1-xGex films are independent of the strain in the original Si1-xGex layer. The results also indicate that PtSi1-xGex does not influence the strain in the Si1-xGex layer. The barrier-height measurements suggest the presence of Fermi-level pinning, and the pinning position is independent of the strain in the alloy, and it is primarily determined by the Ge concentration. As a result of Fermi-level pinning, hole Schottky barrier height of PtSi1-xGex-Si1-xGex contacts is 0.1-0.2 eV higher than that of the PtSi-Si contacts.
Optimization of the efficiency of a singly resonant optical parametric oscillator at pump powers many times above threshold

A method is presented here to determine the dependence of both the threshold and the conversion efficiency of a singly resonant optical parametric oscillator on the focusing conditions of the pump and signal beams, phase mismatch and incident pump power. Strong pump depletion effect is included.
Nicotine and its withdrawal alter feeding induced by paraventricular hypothalamic injections of neuropeptide Y in Sprague-Dawley rats.

Abstract Rationale. Cigarette smoking produces feeding and weight suppression in humans that often rebound following cessation. Nicotine (NIC) administration produces similar effects in rats, but the neural mechanisms responsible are not fully known. Recent evidence shows that hypothalamic levels of neuropeptide Y (NPY) change with NIC administration. Infusions of NPY into the paraventricular nucleus of the hypothalamus (PVN), which normally produce robust feeding, were used to investigate changes in the PVN–NPY system that may contribute to NIC's effects on energy balance. Objective. To characterize potential differences in PVN–NPY-induced feeding during NIC treatment versus withdrawal. Methods. Three groups of female rats (n=66) bearing unilateral PVN cannulae were implanted for 14 days with subcutaneous Alzet mini-pumps containing NIC (0, 6, or 12 mg/kg per day). Dark-onset (1800–2000 hours) NPY feeding tests occurred five times: pre-implant, 2 days and 12 days post-implant and 2 days and 8 days after implant removal. Feeding tests consisted of 1 h of pre-feeding prior to lights off, then two 1-h measures of feeding after PVN injections of 0.4 µl saline or NPY (78 pmol, 235 pmol). Results. NIC initially suppressed body weight gain, followed by steady recovery that was briefly exaggerated after withdrawing NIC. Daily feeding was acutely suppressed by NIC but acutely potentiated after NIC cessation. PVN–NPY-induced feeding was suppressed by both doses of NIC 2 days after pump implant, elevated 2 days after pump removal, but returned to pre-NIC levels 8 days after pump removal. Conclusions. These findings provide behavioral support that changes in PVN–NPY neurotransmission may play a functional role in the food intake and weight-modulating effects of NIC.
The observation of direct attractive interactions between potassium and carbon monoxide coadsorbed on Ru(001)

Abstract We report a study of the interaction between carbon monoxide and metallic (monolayer) potassium on Ru(001). This system is characterized by simultaneous “autocatalytic” desorption of CO and K at 680 K and vibrational CO stretch frequencies of 1350 and 1490 cm −1 . The results suggest direct attractive interaction between the potassium and carbon monoxide.
Microbially Mediated Redox Cycling at the Oxic-Anoxic Boundary in Sediments: Comparison of Animal and Plants Habitats

Microorganisms are responsible for the bulk of transformations that occur in surficial sediments. They are most active at redox boundaries where they can benefit from access to various oxidants and reductants generated during redox cycling events. To illustrate the dynamics of microbially mediated processes, especially those involving sulfur and metal cycles, processes were compared in habitats either bioturbated by a capitellid worm or inhabited by a salt marsh grass. The presence of macrofauna and macroflora greatly altered the three-dimensional array of redox gradients in sediments, but the type and form of reductants and oxidants provided varied greatly; clastic sedimentary infauna subducted solid phase organic material and iron oxides, whereas plant roots released dissolved organic matter and oxygen. These differences resulted in a bioturbated system that exhibited a rapid sulfur cycle (residence time of minutes), but a slower iron cycle (days), whereas vegetation caused a slow sulfur cycle and rapid iron cycle. Alteration of sediments by higher life forms also greatly affected the composition and relative abundances of sedimentary bacteria, even on short time scales. Although redox cycling at interfaces can be somewhat predictable, variations in response to biological and physical perturbations demonstrated wide differences in the dynamics of redox-mediated processes.
Nitrogenous excretory products of the giant south American land snail, Strophocheilus oblongus

Abstract 1. 1. Purine-N, as uric acid, xanthine and guanine, accounts for over 70 per cent of the total N present in the kidney contents (excreta) of Strophocheilus oblongus. Of three other major invertebrate excretory products, urea, NH4+ and amino acids, only the latter two were present, but their contribution to the total N was only 0·2 per cent. 2. 2. Uric acid and NH4+ were also present in the blood of Strophocheilus; no urea was detected in the one specimen examined. 3. 3. Strophocheilus is thus similar in its excretory N metabolism to other terrestrial pulmonates.
Echocardiographic Prevalence of Bicuspid Aortic Valve in the Population

Introduction The exact prevalence of bicuspid aortic valve (BAV) is controversial. We studied the prevalence of BAV using two large independent echocardiographic databases. Methods We analyzed 24,265 echocardiograms performed at our academic institution between 1984 and 1998 for various clinical reasons and 1742 echocardiograms that were obtained by screening teenage athletes in Southern California. The total prevalence of BAV was calculated. Results The first database revealed a gender distribution of 11,339 (47%) male and 12,926 (53%) female patients. The second database consisted of 1172 (67%) male and 570 (33%) female athletes. The echocardiographic prevalence of BAV was 0.6% in the larger database and 0.5% in the smaller athletic database. Conclusion We found the prevalence of bicuspid aortic valve in two large databases to be between 0.5% and 0.6%. This figure was consistent across different ages, in both databases.
Frequency shift of Raman modes due to an applied electric field and domain inversion in LiNbO 3

We report changes in the frequency of Raman modes in lithium niobate that are observed under the application of external applied electric fields and after domain inversion. Inspection of the Raman peaks reveals that after domain inversion, the internal field of the crystal is reduced. A comparison of the respective frequency shifts for the different Raman modes indicates that this change in the local internal field is not limited to the ferroelectric axis, but the fields orthogonal to the ferroelectric axis also change. The Raman modes also reveal that the strength of the internal field is dependent on the concentration of intrinsic defects present in the crystal.
Bridging “expert” and “local” knowledge for counter-disaster planning in urban South Africa

Rapid and spatially concentrated urbanization in South Africa has brought with it significant health and safety hazards. Political democracy and the dismantling of apartheid open the possibility of vigorous community participation in the identification and mitigation of such hazards. However there are severe obstacles to combining the expert knowledge of outside scientists with local knowledge of residents of the townships and squatter camps. This papers describes the common genesis of urban environmental hazards and the split between expert and local knowledge. They arise as twin products of the apartheid system that destroyed rural livelihoods, forcing Africans into over-crowded urban enclaves, denied them most educational opportunities and skilled employment, and denigrated local knowledge and self-help initiatives. This legacy must be overcome in the interest of hazard reduction in the New South Africa.
Natural constraints on metamorphic reaction rates

Abstract Quantitative constraints on the rates at which metamorphic reactions proceed in nature are now available from several sources. Most common are predictions made on the basis of laboratory kinetic data. However, the applicability of such laboratory-based predictions has long been questioned and many observations in the field now suggest much slower rates. Here, published quantitative field-based constraints on high temperature (>400 °C) reaction rates are assembled from a variety of sources. Reaction rates attending regional metamorphism are four to seven orders of magnitude slower than most laboratory-based predictions. A general rate law for regional metamorphism has been derived which best describes these field-based data: log 10 ( R net ) ≅ 0.0029 T − 9.6 ± 1 where R net is the net reaction rate (g/cm 2 /a) and T is temperature (°C). At the same time, natural reaction rates attending contact metamorphism differ from laboratory-based predictions by less than two orders of magnitude, and are in close agreement at higher temperatures. Thus, while existing laboratory-based kinetic data may be judiciously applied to some contact metamorphic systems, laboratory-based kinetic predictions clearly misrepresent regional metamorphism. To explain this kinetic discrepancy, regional metamorphic reaction rates may be limited by slow intergranular transport due to comparatively limited (or transient) availability of aqueous fluid in the intergranular medium. The general field-based rate law may be applied to regional metamorphic, and other environments (i.e. ultrahigh pressure or ultrahigh temperature metamorphism), if similar system characteristics (mainly, low aqueous fluid content) can be inferred.
Variation in childhood asthma among former preterm infants.

Abstract Objectives The role of in utero and perinatal exposures in modifying asthma risk among children born prematurely was assessed. Study design Former preterm children (n = 251) were identified from a birth cohort. Examinations, including lung function testing, were performed at ages 8 to 11 years. Perinatal exposures were ascertained from neonatal medical records. Results Univariate predictors of asthma included male gender, African American ethnicity, maternal asthma, and birth weight. Asthmatics were less likely to have been small for gestational age (SGA) than nonasthmatics (12.4% vs 22.7%, P = .04) and had more neonatal pulmonary disease. After adjusting for maternal asthma and demographic factors, asthma was associated with chronic lung disease of infancy, neonatal mechanical ventilation and corticosteroid use, and a higher childhood body mass index. Children who were septic postbirth and girls who were SGA were less likely to have asthma (OR for sepsis, 0.2; 95% CI, 0.1–0.6; OR for girls who were SGA compared with girls who were not SGA, 0.05; CI, 0.01–0.34). Conclusions Among premature children, female SGA status and neonatal sepsis appear protective relative to the development of childhood asthma. Differential susceptibility to asthma among preterm children may relate to exposures that operate in the in utero and early postnatal environment to accelerate lung development, alter innate immunity, or both.
The taxonomy of yeasts found in exudates of certain trees and other natural breeding sites of some species of Drosophila.

A survey was made of the yeasts occurring in slime fluxes ofQuercus kellogii (black oak),Abies concolor (red fir) and in certain mushrooms and dead logs in the mountains of the Yosemite region of California. Most of the 134 isolates identified were found to be non-fermentative or poorly fermentative (fermenting glucose only and usually weakly). The isolates were placed in the following genera:Pichia (34),Debaryomyces (35), imperfect forms ofHansenula (39),Endomyces (3),Saccharomyces (2),Candida (11),Trichosporon (7),Torulopsis (1),Cryptococcus (1) andSporobolomyces (1). Four new species have been described,Pichia silvestris, Pichia quercibus, Pichia carsonii andDebaryomyces fluxorum. P. quercibus andP. carsonii are unusual representatives of the genusPichia in that they form a very primitive pseudomycelium and lack pellicles on malt extract. To accommodate such species an amended diagnosis of the genusPichia has been proposed byPhaff in an accompanying paper.Saccharomyces pastori, of which 12 isolates were obtained, has been transferred to the amended genusPichia asP. pastori (Guilliermond) nov. comb.
Solidification modeling and solid-state transformations in high-energy density stainless steel welds

The solidification and solid-state transformations which occur during the high-energy density (HED) welding of austenitic stainless steel were studied. Comparisons were made between structures observed in gas tungsten arc (GTA) welds and those of electron beam (EB) and laser welds using Fe-Ni-Cr ternary alloys with Cr/Ni ratios ranging from 1.5 to 1.85. Weld solidification and microsegregation was modeled using a finite difference analysis and compared with experimental results. These calculations were also used to help interpret the origin of the observed microstructures. Calculations showed that little solid-state diffusion occurs during the solidification and cooling of primary austenite solidified welds, whereas structures which solidify as ferrite may become almost completely homogenized as a result of diffusion. A change in solidification mode from primary austenite to primary ferrite was found to occur at higher Cr/Ni ratios with the HED welds than with GTA welds and is attributed to dendrite tip undercooling. A nearly segregation-free, single-phase austenite structure which appears to be unique to the rapid solidification velocities and cooling rates of HED welds was also observed. It is suggested that this structure is a product of ferrite solidification which transforms to austenitevia a massive transformation.
Suicidal intent in adolescence: A hypothesis about the role of physical illness

Observations made on 13 adolescent patients seen at a medical unit who have threatened, attempted, or actually committed suicide are reported. The evidence supports a hypothesis about a sex difference in the meaning of expressed suicidal intent in an adolescent population, as well as a difference in the capacity of the two sexes to tolerate the “sick role”. Physical illness seems to influence suicidal preoccupation in boys when that illness is experienced as an insurmountable obstacle to achieving the competency necessary for masculine identity. The young girl, it is suggested, will tolerate illness to the extent that it induces the care and support of important others but may find illness intolerable when it is experienced as the cause of a rejection.
The influence and utility of varying field strength for the separation of tryptic peptides by ion mobility-mass spectrometry

The influence of field strength on the separation of tryptic peptides by drift tube-based ion mobility-mass spectrometry is reported. Operating the ion mobility drift tube at elevated field strengths (expressed in V cm−1 torr−1) reduces separation times and increases ion transmission efficiencies. Several accounts in the literature suggest that performing ion mobility separation at elevated field strength can change the selectivity of ion separation. To evaluate the field strength dependant selectivity of ion mobility separation, we examined a data set of 65 singly charged tryptic peptide ion signals (mass range 500–2500 m/z) at six different field strengths and four different drift gas compositions (He, N2, Ar, and CH4). Our results clearly illustrate that changing the field strength from low field (15 V cm−1 torr−1) to high field (66 V cm−1 torr−1) does not significantly alter the selectivity or peak capacity of IM-MS. The implications of these results are discussed in the context of separation methodologies that rely on the field strength dependence of ion mobility for separation selectivity, e.g., high-field asymmetric ion mobility spectrometry (FAIMS).
Near tribimaximal neutrino mixing with Δ(27) symmetry

Abstract The discrete subgroup Δ ( 27 ) of SU ( 3 ) has the interesting multiplication rule 3 × 3 = 3 ¯ + 3 ¯ + 3 ¯ , which is used to obtain near tribimaximal neutrino mixing. Using present neutrino oscillation data as input, this model predicts that the effective mass m e e measured in neutrinoless double beta decay will be 0.14 eV.
The role of neurotrophins in brain aging: a perspective in honor of Regino Perez-Polo.

During brain aging and progression of Alzheimer’s disease, the levels of Aβ and proinflammatory cytokines accumulate very early in the pathogenic process prior to any major degenerative changes. Accumulation of these molecules may impair with signal transduction pathways critical for neuronal health. Neurotrophin signaling is a critical mechanism involved in synaptic plasticity, learning and memory and neuronal health. We have recently shown that exposure to low levels of Aβ impairs BDNF trkB signal transduction, suppressing the Ras/ERK, and the PI3-K/Akt pathways but not the PLCγ pathway. As a result, downstream regulation of gene expression and neuronal viability are impaired. Recently, we have found that at least three agents – Aβ, TNFα, Il-1β – suppress TrkB signaling and act via a common and novel mechanism. These factors all regulate the docking proteins (e.g., IRS and Shc) that link the activated Trk receptor to downstream effectors. While this is a novel mechanism underlying regulation of Trk signaling, such a mechanism has been identified for the insulin/IGF-1 receptor in the presence of proinflammatory cytokines and is one of the mechanisms for insulin/IGF-resistance, which is a key risk factor for type II diabetes (1). We suggest that accumulation of AB and proinflammatory cytokines during aging generates in the brain a “neurotrophin resistance” state that places the brain at risk for cognitive decline and dementia.