cssi/SciSciGPT-SciSciNet huggingface dataset:
CVaR as a Measure of Risk: Implications for Portfolio Selection

In this paper, we analyze the implications arising from imposing a Conditional Value-at-Risk (CVaR)constraint in an agent's portfolio selection problem, and compare them with those arising from the imposition of a Value-at-Risk (VaR) constraint. For a given confidence level, a CVaR constraint is tighter than a VaR constraint is the CVaR and VaR bounds coincide. Consequently, a CVaR constraint is more effective than a VaR constraint as a tool to control slightly risk-averse agents, but has a perverse effect in that it may force highly risk-averse agents to select portfolios with larger standard deviations. While this effect may also occur with the use of a VaR constraint, it is even more perverse and more likely to occur with a CVaR constraint. However, when the CVaR bound is appropriately larger than the VaR bound, a CVaR constraint 'dominates' a VaR constraint as a risk management tool.
Referencing the Imaginary: An Analysis of Library Collection of Role-Playing Game Materials

The most famous role-playing game, Dungeons & Dragons, recently celebrated the fortieth anniversary of its release. The books that define the games in the role-playing genre function like sports rulebooks, contain entries like encyclopedias, or are based on collections of maps similar to those in atlases. In the library context, this places the books that define role-playing games in the domain of reference books. While currently divisions of the American Library Association encourage librarians to consider using the game in community-building and youth services, there was a time period where organized groups actively tried to discourage librarians from collecting materials associated with the genre. This study is an assessment of library holdings of role-playing game materials worldwide, detailing collection and cataloging issues associated with the genre.
Configuration Space Formulation and Implications for Approximation Schemes for Strongly Coupled Plasmas

Some of the recent approximation schemes [Singwi, Tosi, Land and Sjolander, 1968 (STLS); Totsuji and Ichimaru, 1973 (TI), Golden, Kalman and Silevitch, 1974 (GKS)] for strongly coupled plasmas have been formulated in terms of integral equations in k-space for the pair correlation function, or the structure function, or other related quantities. The integrand, one observes, often has (almost) a convolution structure, which strongly suggests that a transition to the configuration space may simplify the problem and offer some specific advantages. We have so transformed [Bakshi, Kalman, Silevitch and Golden, 1976] the STLS and TI equations (Section II), which appear now as Poisson equations for the direct correlation function, with distinctive source terms involving the pair correlation function. This, in turn, suggests that the direct correlation function (properly normalized) must be an effective potential due to an effective charge density of the source. Indeed, the source terms, in both cases, obey the same normalization condition which essentially reflects the requirement of perfect screening. Various other physical requirements and their implications for the correlation functions and the source function are also noted in Section III.
The application of dynamic programming to the optimal ordering of digital filter sections

Dynamic Programming has been applied to a number of digital signal processing problems. In this paper we discuss its well known application to the problem of determining the optimum order of sections in a digital filter realization. We show that the method is quite insensitive to the specific details of the problem; it is applicable over a wide range of possible optimality criteria, various kinds of arithmetic, scaling options, etc. This is characteristic of the application of dynamic programming to many signal processing problems. Also, since a problem, to be solved by dynamic programming, must be represented as the traversal of a directed graph, we usually discover unsuspected structure in the problem when we attempt to solve it using dynamic programming. Quite often it is necessary to recognize this structure in order to solve the problem efficiently. In the case of ordering of filter sections the structure leads to an efficient utilization of memory.
Cell growth regulation in epithelial ovarian cancer

BACKGROUND: As in the case of other epithelial neoplasms, most ovarian cancers arise from single clones of cells that have undergone multiple genetic alterations. A comparison of normal and malignant ovarian epithelium has identified several differences in growth regulation by peptide growth factors, protooncogenes, and tumor suppressor genes. METHODS: Recent articles and abstracts have been reviewed. RESULTS: The malignant ovarian epithelial phenotype has been associated with (1) autocrine growth stimulation by transforming growth factor-alpha, (2) loss of autocrine growth inhibition by transforming growth factor-beta, (3) mutation or amplification of ras in 2-12% of cases, (4) amplification of myc in 23% of specimens, (5) expression of fms in 56% of cases with potential autocrine stimulation by macrophage colony stimulating factor, (6) paracrine stimulation by macrophage products including interleukin-1, interleukin-6 and tumor necrosis factor, (7) overexpression of c-erbB-2 (HER-2/neu) in 30% of cases, and (8) mutation with consequent overexpression of p53 in 50% of advanced ovarian cancers. A poor clinical prognosis is associated with expression or overexpression of the epidermal growth factor receptor, fms, and HER-2/neu. Antibodies against the extracellular domain of the HER-2/neu gene product p185 inhibit the growth of tumor cells that overexpress HER-2/neu and are associated with marked decreases in diacylglycerol levels. The intracellular kinase domain is required for growth inhibition. Antibodies that inhibit growth stimulate phosphorylation of intracellular substrates. Ricin A chain monoclonal antibody conjugates that react with p185 also inhibit the growth of tumor cells that overexpress p185. The intracellular kinase region is not required for immunotoxin-mediated killing. Coexpression of HER-2/neu and the epidermal growth factor receptor has been observed in 65% of epithelial ovarian cancers and in a limited number of normal tissue from a fraction of donors. CONCLUSIONS: Multiple alterations in growth factors, protooncogenes and growth factors have been detected in different epithelial ovarian cancers. Inappropriate signalling from receptor tyrosine kinases may be particularly important for ovarian oncogenesis. Drugs that affect tyrosine kinase and phosphatase activity deserve attention as potential therapeutic agents for ovarian cancer. The extracellular domains of the HER-2/neu gene product p185 and the epidermal growth factor receptor may provide useful targets for serotherapy.
Effect of Temperature on the Fermi Surface of Beryllium

By straightforward extension of the pseudopotential model which was originally developed for pure beryllium at 0\ifmmode^\circ\else\textdegree\fi{}K, it is shown how to obtain the changes in the Fermi surface with temperature. Because of the very high Debye temperature of Be, the changes even at room temperature are not large. In particular, the calculations show that there are no changes in topology of the Fermi surface with rise in temperature and that the probability of breakdown between orbits in a magnetic field is not significantly enhanced.
Serial Polygyny, Negro Peasants, and Model Analysis

M. G. Smith's remarks are, I believe, particularly pertinent to one aspect of Negro life which has received considerable attention, namely, mating patterns and the family. Various works attempt to convince us of the African background of this complex (Herskovits 1941, 1947), of its origin in slavery (Frazier 1939; Henriques 1953; Matthews 1953), of its particular ties to economics (R. T. Smith 1956, 1957), and recently of its possible connections to European patterns (Arensberg 1957). It might be rewarding to examine some actual field data in order to arrive at an understanding of the mating system first and then attempt statements of probable connections between this system and others.1 The approach suggested is based on the assumption that sociocultural phenomena, such as the mating behavior, are systematic. Such an assumption is in agreement with modern theoretical thinking. Many, including the writer, agree with Meadows that today "the system" is the master model, and that "the image of systems . . . has indeed become the central notion of theoretical work in such diverse areas as physiology, psychology, economics, biology, and sociology and many interdisciplinary studies" (Meadows 1957:5; italics mine). The "systems" approach will be used in this paper. First, however, a methodological problem must be tackled: how does one present and analyze sociocultural data to arrive at the system? Following Levi-Strauss, one builds a "mechanical model" which has the following characteristics:
Molecular Dynamics Simulation of Amorphous Poly(ethylene terephthalate)

A conformational energy model has been set up for poly(ethylene terephthalate) (PET) for use in molecular dynamics simulations. The molecular dimensions, as expressed by the characteristic ratio, and the dipolar correlation factor of PET are key parameters in the simulations because they depend very differently on the conformational characteristics of the individual bond types in the chain. These parameters as well as the equation of state of the melt were emphasized in testing the model, and satisfactory representation was accomplished. It was found, however, difficult to achieve the experimental glass volume in MD cooling experiments below Tg. Packing features of bulk PET are discussed in terms of radial distribution functions. Dipolar correlation was found to be largely intramolecular in nature.
Optimal Conditions for Long Term Storage of Native Collagens

Abstract Cryopreservation was used to maintain the biological activity of collagen, i.e., its fibril formation property, after isolation from tissues. Freezer temperatures commonly available in laboratories, -15°C and -90°C, and liquid nitrogen temperature, -196°C, were compared for efficacy in preserving both type I collagen structure (amino acid and subunit composition, triple helix) and activity (fibril formation in vitro ). Whether the collagen was stored dry or in acetic acid solution at -196°C, the kinetics of fibril formation were completely stable for at least two and a half years, but decreased after several months storage at -15°C or -90°C. Types II and III collagens, also with intact nonhelical ends, are also completely stable in liquid nitrogen for at least two and a half years.
The crypt surface of blade-vent implants in clinical failure: An electron microscopic study

Abstract An electron microscopic investigation was undertaken in an attempt to ascertain the nature of the blade-vent implant crypt wall in clinical failures. All observations were made on tissues removed from the crypt surface of endosseous metal implants placed in the jaws of both human subjects and rhesus monkeys. From the information currently available and the results obtained in this investigation, two conclusions appear to emerge with some degree of clarity. First, animal experimentation has demonstrated a highly vascular osteogenic connective tissue lining the implant crypt in clinically successful cases. Second, electron microscopic analysis of tissue obtained from both man and monkey and from all levels of the implant crypt surface of clinically failing blades revealed: (1) delayed osteogenesis, (2) epithelial cell migration along the entire crypt surface, (3) persistent inflammation, and (4) a thick subepithelial connective-tissue component composed of collagen fibers and inflammatory cells.
Operation of Large D-C Motors From Controlled Rectifiers

The d-c output voltage of a typical power rectifier has more ripple than the output of a d-c generator. The ripple increases as the number of rectifier phases is decreased. It also increases as the rectifier voltage is reduced by phase retard. The voltage ripple affects the performance of d-c motors in the following respects: 1. Heating. 2. Commutation. 3. Speed regulation, particularly when current is discontinuous. D-c motors constitute the major part of the load of general purpose power rectifiers. It is a matter of experience that d-c motors in the fractional horsepower and small integral horsepower ranges must be derated when they are operated over a wide speed range from rectifiers with voltage control. The factors which result in derating of these motors are present to a very limited extent in general purpose rectifiers, which usually have six or more phases and are seldom operated with more than 15 per cent phase control. Hence little consideration has been given to the derating of motors connected to such rectifiers. In recent times the extension of controlled rectifier drives to d-c motors in the range of 100 horsepower or more has raised the question of modifying the rating of these larger motors when operated from rectifiers with phase control.
The relationship of gingival bradykinin activity to chronic gingivitis and periodontitis.

THE EFFECT ON HUMAN SUPRAGINGIVAL CALCULUS FORMATION OF ACETOHYDROXAMIC ACID Sons, S. and Muhlemann, H. R. Helv. Odontol. Acta, 15:158, Supplementum VII, October, 1971 Rinsing twice daily with a 1.5 percent solution of acetohy- droxamic acid in ten dental students ages 22 to 25 years of age was assessed using the standardized foil technique of Muhle- mann and Schroeder (1964). No significant decreases in cal- culus formation were found but there were significant differ- ences in dry weights of the samples, collected at the end of seven days of exposure to the oral environment. Dental Insti- tute, University of Zurich, Department of Cariology and Perio- dontology, Zurich, Switzerland.
The static and dynamic behavior of MEMS arches under electrostatic actuation

In this paper, we investigate the static and dynamic behavior of electrostatically actuated clamped-clamped micromachined arches. The Galerkin method is used to discretize the distributed-parameter model of the considered shallow arch, and thus approximate it by a set of nonlinear algebraic equations and ordinary-differential equations describing its statics and dynamics. Five symmetric mode shapes of either a straight beam or a deformed arch is found to be sufficient to simulate the static and dynamic behavior of the arch. The natural frequencies and mode shapes of the arch are calculated for various values of DC voltages and initial rises of the arch. The forced vibration response of the arch to a combined DC and AC harmonic load is determined when excited near its fundamental natural frequency. The results show various nonlinear behaviors, such as hysteresis, softening behavior, and dynamic pull-in. Several scenarios of snap-through and pull-in are shown, which found depend on the initial rise of the arch.
Overexpression of membrane glycoprotein PC-1 can influence insulin action at a post-receptor site

An elevated content of membrane glycoprotein PC-1 has been observed in cells and tissues of insulin resistant patients. In addition, in vitro overexpression of PC-1 in cultured cells induces insulin resistance associated with diminished insulin receptor tyrosine kinase activity. We now find that PC-1 overexpression also influences insulin receptor signaling at a step downstream of insulin receptor tyrosine kinase, independent of insulin receptor tyrosine kinase. In the present studies, we employed Chinese hamster ovary cells that overexpress the human insulin receptor (CHO IR cells; ∼106 receptors per cell), and transfected them with human PC-1 c-DNA (CHO IR PC-1). In CHO IR PC-1 cells, insulin receptor tyrosine kinase activity was unchanged, following insulin treatment of cells. However, several biological effects of insulin, including glucose and amino acid uptake, were decreased. In CHO IR PC-1 cells, insulin stimulation of mitogen-activated protein (MAP) kinase activity was normal, suggesting that PC-1 overexpression did not affect insulin receptor activation of Ras, which is upstream of MAP kinase. Also, insulin-stimulated phosphatidylinositol (PI)-3-kinase activity was normal, suggesting that PC-1 overexpression did not interfere with the activation of this enzyme by insulin receptor substrate-1. In these cells, however, insulin stimulation of p70 ribosomal S6 kinase activity was diminished. These studies suggest, therefore, that, in addition to blocking insulin receptor tyrosine kinase activation, PC-1 can also block insulin receptor signaling at a post-receptor site. J. Cell. Biochem. 68:366–377, 1998. © 1998 Wiley-Liss, Inc.
Phosphorylation of vesicular stomatitis virus M protein: evidence for a second virion-associated protein serine kinase activity.

Abstract The vesicular stomatitis virus (VSV) NS and M proteins are not only phosphorylated in vivo but are also further modified by the virion-associated protein kinase(s) concomitantly with the in vitro transcription process. Although NS phosphorylation is necessary for this transcription, no function has yet been ascribed for M protein phosphorylation. We show here that all phosphates added to M protein in vitro mapped to the trypsin-sensitive N-terminal basic domain (residues 1–43). The major site(s) (∼93%) corresponded to one or more of three serine residues within the first 17 amino acids. Nearly 1 mol phosphate/mol protein was added in vitro under optimal conditions suggesting that only one of these three candidate serine residues corresponds to the major site. This same M protein domain is thought to play an important role in virus RNA synthesis by inhibiting transcription. We show here that in vitro phosphorylation did not appear to affect this function. Two critical serine residues in the VSV NS protein were previously reported to be phosphorylated during in vitro transcription ( D. Chattopadhyay and A. K. Banerjee, 1987, Cell 49, 407–414 ). The sequence flanking these NS serines is very acidic while that of all three candidate phosphoserines in the M protein is very basic. We therefore predict that at least two distinct serine-specific kinase activities are packaged in virions, one specific for M and one specific for NS.
Reactivation of latent feline leukaemia virus infection

In most cats exposed to the contagious1 feline leukemia virus (FeLV), viral replication is contained in target haematopoietic tissues2 and elicits humoral immunity to FeLV and to the feline oncornavirus-associated cell membrane antigen (FOCMA)3–6. Recently, we and others have considered that these ostensibly self-limiting infections might be persistent nonproductive (latent) infections in certain haematopoietic cells. This hypothesis could account for the relapsing viraemias7, protracted incubation periods8, persistently high titres of antiviral and anti-FOCMA antibodies8, appearance of FeLV p27 antigen in serum of otherwise non-viraemic animals9 and occurrence of FeLV -negative but FOCMA-positive leukaemias in naturally infected pet cats10,11. Here we describe the reactivation of latent FeLV from myelomonocytic and lymphoid cells of cats immune to FeLV, cats bearing FeLV-negative tumours, and kittens congenitally exposed to FeLV. Furthermore, the reappearance of FeLV infection is suppressed by the host's immune system but this can be altered by adrenal corticosteroid hormones in vivo and in vitro.
Letters of Recommendation to an Otolaryngology/Head and Neck Surgery Residency Program: Their Function and the Role of Gender

Objectives/Hypothesis: To ascertain common features and gender differences in letters of recommendation (LORs) for applicants to an otolaryngology/head and neck surgery (OHNS) residency program. Study Design: Retrospective review. Methods: Seven hundred sixty-three LORs submitted to one OHNS residency program in 2006 were reviewed. Results: All 763 letters “recommended” the applicant for OHNS residency. Ninety-one percent of letters were written by men, 68.4% by male otolaryngologists (OTOs), 4.2% by female OTOs, and 33% by OHNS department chairs or division chiefs (100% men). A comparison of female and male letter writers revealed five categories with significant differences: female letter writers were more likely to call an applicant a “team player” (P = .000), “compassionate,” (P = .001) and use strings of adjectives (P = .024). In contrast, they were less likely when compared with male letter writers, to mention an applicant's personal life (P = .003), or write “letters of minimal assurance” (P = .035). Evaluation of the letters by applicant gender revealed two findings: letter writers were more likely to use a gender term in letters for male applicants (P = .004), and male letter writers were more likely to make reference to a female candidate's physical appearance (P = .040). Conclusions: LORs for OHNS residency universally advocate for the applicant. The letters are writtenpredominately by the highest-ranking male OTOs in academic medicine. In the LORs, male and female applicants are described similarly. Male and female letter writers, however, often describe applicants in different ways regardless of applicant gender.
Thick-Target Measurements and Astrophysical Thermonuclear Reaction Rates: Alpha-Induced Reactions

We have studied 72 proton-induced reactions on a variety of targets from /sup 10/B through /sup 152/Sm. These include (rho,..cap alpha..), (rho,..gamma..), and (rho,n) reactions leading to various ..beta.. or ..beta.. and ..gamma.. unstable final state nuclei. By measurement of the activity of the product nucleus we extract a normalized thick-target yield as a function of the energy in the center-of-mass system. An appropriate integration in energy of the yield function then allows calculation of the thermonuclear reaction rate, N/sub A//sub T/, as a function of temperature. Extensive tables of yields and rates are given primarily for use in astrophysical applications.
Normal state properties at a field-tuned quantum-critical point in the heavy-fermion superconductor CeRhIn5

Abstract CeRhIn 5 is a prototypical heavy-fermion antiferromagnet where the localized 4f electron of Ce hybridizes weakly with ligand electrons. Applying pressure suppresses the antiferromagnetism and induces unconventional superconductivity when the same Ce 4f electrons become delocalized and participate in the formation of Cooper pairs. The emergent superconducting phase unavoidably hides the existence of quantum-critical point, preventing direct access to it. Measurements of the heat capacity and electrical resistivity under magnetic field and pressure reveal unusual normal state properties at a projected quantum-critical point ( P 2 ) : divergence in C / T and sublinear temperature dependence in the resistivity.
Learning with Laptops: A Multi-Method Case Study

This article examines the implementation of a one-to-one laptop program in three diverse schools in California. The program was carried out in one largely Hispanic low socio-economic junior high, o...
The effects of naloxone on courtship and pairing behaviour in male and female zebra finches: the importance of testing mechanisms using multiple paradigms

Opioids are implicated in social attachments, but their role in avian pair bonds is not well understood. The present study tested the effects of naloxone, an opioid antagonist, on pairing using both a forced-choice and a mixed-sex aviary paradigm. First, three doses of naloxone were systemically administered in males using a repeated measures forced-choice design, partner preference formation was tested on the second day. Males treated with 20 mg/kg sang less undirected song. Males treated with 10 mg/kg of naloxone sang less to the familiar partner than when treated with saline and were less likely to form a partner preference than were other treatments. In females, 10 mg/kg of naloxone in a forced-choice paradigm increased preference for the unfamiliar over the familiar male. Finally, males and females were administered either naloxone (10 mg/kg) or saline in a mixed-sex aviary. In females, naloxone increased pairing behaviours, but had no other effects in either sex. Our findings suggest that the effects of naloxone on pairing-related behaviours are context-dependent; male–male competition may decrease the effects of naloxone on male song and a choice of mates may increase affiliation in females in a semi-naturalistic paradigm, and increase preferences for an unfamiliar partner in a forced-choice paradigm. Our findings highlight the importance of using multiple paradigms to test mechanisms of behaviour. These findings contribute to our understanding of the mechanisms of monogamous relationships and suggest that opioids play a role in male courtship, female affiliation and partner preferences in both sexes of zebra finches, but that context is important.
Stress-induced roughening in epitaxial growth

Surfaces under stress (such as strained layers in heteroepitaxy) are unstable or metastable against morphological changes. This paper reviews recent progress in understanding such stress-induced roughening, and describes a few of the fascinating ways in which this instability can manifest itself.
Computation of the Redox and Protonation Properties of Quinones: Towards the Prediction of Redox Cycling Natural Products.

Quinone metabolites perform a variety of key functions in plants, including pathogen protection, oxidative phosphorylation, and redox signaling. Many of these structurally diverse compounds have been shown to exhibit potent antimicrobial, anticancer, and anti-inflammatory properties, although the exact mechanisms of action are far from understood. Redox cycling has been proposed as a possible mechanism of action for many quinone species. Experimental determination of the essential thermodynamic data (i.e. electrochemical and pKa values) required to predict the propensity towards redox cycling is often difficult or impossible to obtain due to experimental limitations. We demonstrate a practical computational approach to obtain reasonable estimates of these parameters.
Screening ultrasound in follow-up after pediatric pyeloplasty.

OBJECTIVES To investigate whether an initial ultrasound (US) adequately identifies those patients who need further investigation and possibly intervention while decreasing instrumentation and radiation exposure. The recommended imaging after pediatric pyeloplasty has included intravenous pyelography, radionucleotide renography, and ultrasound US. METHODS We retrospectively reviewed pediatric open pyeloplasty cases performed between 1999 and 2007. Of 116 patients reviewed, 49 met the inclusion criteria of unilateral pyeloplasty with pre- and postoperative US and mercaptoacetyltriglycine (MAG-3). Hydronephrosis was judged by anterior posterior pelvic diameter and caliectasis. Change in renal function on MAG-3 was defined as increase or decrease in function >5%. RESULTS Of 49 patients, 42 (85.7%) showed improved or stable hydronephrosis postoperatively and 7 (14.3%) showed increased hydronephrosis. Forty-six (93.8%) patients had either improved or stable renal function. Of 42 patients with stable or improved hydronephrosis, 41 (97.6%) also had stable or improved function. Comparatively, of 7 patients with increasing hydronephrosis, 2 (28.6%) showed deteriorated renal function, P = .05. CONCLUSIONS Postpediatric pyeloplasty imaging should aim to identify those who require further intervention. Our data demonstrate that at-risk patients can be identified with a sentinel US and selectively determine who needs further MAG-3 investigation. This should increase compliance while decreasing costs, instrumentation, and radiation exposure.
Rf Gun Photo-Emission Model for Metal Cathodes Including Time Dependent Emission

The quantum efficiency from a metal cathode is strongly dependent on the field at the cathode due to the Schottky effect. Since the field is time dependent the quantum efficiency is also time dependent. Thus the laser pulse shape used to generate electrons in a photocathode rf gun is not the same as the electron bunch shape. In addition since the thermal emittance and quantum efficiency are related, the thermal emittance is also time dependent.
The Effects of Hydrogen Dilution on VOC in a-Si:H Pin Solar Cells

We study the effects of hydrogen dilution on the open circuit voltage of a-Si:H pin solar cells fabricated by rf glow discharge growth. We keep the p and n layers the same and only vary the i layer properties. A normal a-Si:H i layer, an H-diluted i layer, and a thin H-diluted layer inserted between p and normal i layer are selected for this study. We measure the JV characteristics and the internal electric field distribution using a transient-null-current technique both in annealed and light soaked states. We find that hydrogen dilution does stabilize the Voc either in a bulk H-diluted i layer or in a thin layer between p and normal i layer after 100 hours AMI sun light soaking. From dark IV measurement, both H-diluted cells show little change in current at voltage near Voc before and after light soaking; while the normal a-Si:H cell does show a noticeable change. Also the internal field measurements find a stronger electric field starting from p and i interface for both H-diluted cells compared to the normal a-Si:H cell. Furthermore, there are no measurable changes in the field profiles after 100 hour AMI light-soaking for both H-diluted and normal a-Si cells. All these suggest that hydrogen dilution increases the field strength near p and i interface, which is the key that leads to a more stable Voc of H-diluted cells.
Underdeveloped Extraocular Muscles in the Naked Mole-Rat (Heterocephalus glaber)

The extraocular muscles (EOM), the effector arm of the ocular motor system, have a unique embryological origin and phenotype. The naked mole-rat (NMR) is a subterranean rodent with an underdeveloped visual system. It has not been established if their ocular motor system is also less developed. The NMR is an ideal model to examine the potential codependence of oculomotor and visual system development and evolution. Our goal was to compare the structural features of NMR EOMs to those of the mouse, a similar sized rodent with a fully developed visual system. Perfusion-fixed whole orbits and EOMs were dissected from adult NMR and C57BL mice and examined by light and electron microscopy. NMR orbital anatomy showed smaller EOMs in roughly the same distribution around the eye as in mouse and surrounded by a very small Harderian gland. The NMR EOMs did not appear to have the two-layer fiber distribution seen in mouse EOMs; fibers were also significantly smaller (112.3 +/- 46.2 vs. 550.7 +/- 226 sq microm in mouse EOMs, *P < 0.05). Myofibrillar density was less in NMR EOMs, and triad and other membranous structures were rudimentary. Finally, mitochondrial volume density was significantly less in NMR EOMs than in mouse EOM (4.5% +/- 1.9 vs. 21.2% +/- 11.6, respectively, *P < 0.05). These results demonstrate that NMR EOMs are smaller and less organized than those in the mouse. The "simpler" EOM organization and structure in NMR may be explained by the poor visual ability of these rodents, initially demonstrated by their primitive visual system.
Thymine methyls and DNA–protein interactions

Evidence is summarized showing that thymine methyls are as important in the recognition of specific sequences by proteins as are the more widely recognized hydrogen bonding sites of bases in the major groove (1). Strongest evidence has come from experiments using functional group mutagenesis (2) in which thymines in a specific recognition sequence (e.g., promoters, operators and restriction sites) are replaced by oligonucleotide synthesis with methyl-free uracil or cytosine and 5-methylcytosine. Such experiments have shown that thymine methyls can provide contact points via van der Waals interactions with amino acid side chains of specific DNA binding proteins. Actual contact between a thymine methyl and carbons of a glutamine side chain has been observed in a cocrystal of the phage 434 repressor and its operator by X-ray analysis. The issue of why thymine occurs in DNA is discussed in light of these findings.
Heavy metal residues in Laysan Duck feathers

Abstract The heavy metal data presented herein indicate that the wild Laysan Duck population may not be contaminated with metal-laden industrial wates. It is therefore possible that the food chain which supports the duck population is uncontaminated, with the possible exception of prey taken from pelagic sea bird carcasses. Such a short, geographically isolated food chain, involving a non-migratory avian carnivore, could be an ideal system for the investigation of bio-concentration, bio-accumulation and bio-magnification of naturally occurring heavy metals.
Reverse osmosis on a small barrier island: transformations of water, landscape, and vulnerability on Ocracoke Island, NC, USA

Globally, modifications to the landscape have drastically transformed social and ecological communities. The implication of global climate change for small islands and small island communities is especially troublesome. Socially, small islands have a limited resource base, deal with varying degrees of insularity, generally have little political power, and have limited economic opportunities. The physical attributes of small islands also increase their vulnerability to global climate change, including limited land area, limited fresh water supplies, and greater distances to resources. The focus of this research project is to document place-specific human–environmental interactions from a political ecology perspective as a means to address local concerns and possible consequences of global environmental change. The place in which these interactions are examined is the barrier island and village of Ocracoke, NC. I focus on the specific historical-geography of land and water management on Ocracoke as a means to examine relationships between local human–environmental interactions and environmental change. I provide an account of technological changes in potable water procurement and the paralleling development of island growth (i.e. people, buildings, tourism). Then, relying on interviews with island residents, I consider how advancements in local water infrastructure, specifically the installation of an additional reverse osmosis unit, are hinged on anticipated future economic development. Lastly the social dimensions of change are discussed with specific focus on the increase in housing density and overburdened septic drainage fields in relation to changing hydrologic processes with an examination of how all of these factors affect local vulnerability.
Planning target volumes for radiotherapy: how much margin is needed?

Abstract Purpose: The radiotherapy planning target volume (PTV) encloses the clinical target volume (CTV) with anisotropic margins to account for possible uncertainties in beam alignment, patient positioning, organ motion, and organ deformation. Ideally, the CTV-PTV margin should be determined solely by the magnitudes of the uncertainties involved. In practice, the clinician usually also considers doses to abutting healthy tissues when deciding on the size of the CTV-PTV margin. This study calculates the ideal size of the CTV-PTV margin when only physical position uncertainties are considered. Methods and Materials: The position of the CTV for any treatment is assumed to be described by independent Gaussian distributions in each of the three Cartesian directions. Three strategies for choosing a CTV-PTV margin are analyzed. The CTV-PTV margin can be based on: 1. the probability that the CTV is completely enclosed by the PTV; 2. the probability that the projection of the CTV in the beam's eye view (BEV) is completely enclosed by the projection of the PTV in the BEV; and 3. the probability that a point on the edge of the CTV is within the PTV. Cumulative probability distributions are derived for each of the above strategies. Results: Expansion of the CTV by 1 standard deviation (SD) in each direction results in the CTV being entirely enclosed within the PTV 24% of the time; the BEV projection of the CTV is enclosed within the BEV projection of the PTV 39% of the time; and a point on the edge of the CTV is within the PTV 84% of the time. To have the CTV enclosed entirely within the PTV 95% of the time requires a margin of 2.8 SD. For the BEV projection of the CTV to be within the BEV projection of the PTV 95% of the time requires a margin of 2.45 SD. To have any point on the surface of the CTV be within the PTV 95% of the time requires a margin of 1.65 SD. Conclusion: In the first two strategies for selecting a margin, the probability of finding the CTV within the PTV is unrelated to dose variations in the CTV. In the third strategy, the specified confidence limit is correlated with the minimum target dose. We recommend that the PTV be calculated from the CTV using a margin of 1.65 SD in each direction. This gives a minimum CTV dose that is greater than 95% of the minimum PTV dose. Additional sparing of adjoining healthy structures should be accomplished by modifying beam portals, rather than adjusting the PTV. Then, the dose distributions more accurately reflect the clinical compromise between treating the tumor and sparing the patient.
Genome Evolution: A Bacterium with a Napoleon Complex

Summary New work on an important agricultural pest reveals an unexpected toxin-producing defensive bacterial symbiont. Surprisingly, the symbiont's genome is highly reduced, with genes devoted to polyketide synthesis making up a large fraction of its coding capacity.
A magnetic resonance (MR) microscopy system using a microfluidically cryo-cooled planar coil.

We present the development of a microfluidically cryo-cooled planar coil for magnetic resonance (MR) microscopy. Cryogenically cooling radiofrequency (RF) coils for magnetic resonance imaging (MRI) can improve the signal to noise ratio (SNR) of the experiment. Conventional cryostats typically use a vacuum gap to keep samples to be imaged, especially biological samples, at or near room temperature during cryo-cooling. This limits how close a cryo-cooled coil can be placed to the sample. At the same time, a small coil-to-sample distance significantly improves the MR imaging capability due to the limited imaging depth of planar MR microcoils. These two conflicting requirements pose challenges to the use of cryo-cooling in MR microcoils. The use of a microfluidic based cryostat for localized cryo-cooling of MR microcoils is a step towards eliminating these constraints. The system presented here consists of planar receive-only coils with integrated cryo-cooling microfluidic channels underneath, and an imaging surface on top of the planar coils separated by a thin nitrogen gas gap. Polymer microfluidic channel structures fabricated through soft lithography processes were used to flow liquid nitrogen under the coils in order to cryo-cool the planar coils to liquid nitrogen temperature (−196 °C). Two unique features of the cryo-cooling system minimize the distance between the coil and the sample: (1) the small dimension of the polymer microfluidic channel enables localized cooling of the planar coils, while minimizing thermal effects on the nearby imaging surface. (2) The imaging surface is separated from the cryo-cooled planar coil by a thin gap through which nitrogen gas flows to thermally insulate the imaging surface, keeping it above 0 °C and preventing potential damage to biological samples. The localized cooling effect was validated by simulations, bench testing, and MR imaging experiments. Using this cryo-cooled planar coil system inside a 4.7 Tesla MR system resulted in an average image SNR enhancement of 1.47 ± 0.11 times relative to similar room-temperature coils.
How HIV finds the door

The plasma membrane (PM) is a physical barrier that must be breached when pathogens like HIV enter and exit cells. In most cell types, HIV egress begins when the structural Gag protein binds and assembles on the inner leaflet of the PM (Fig. 1). Gag assembly distends the membrane into a spherical virion that is released by a membrane fission reaction catalyzed by the cellular endosomal sorting complexes required for transport (ESCRT) machinery (1). HIV must therefore target the PM selectively to avoid futile release into intracellular compartments. Previous studies have revealed important aspects of the targeting mechanism (2, 3), but the pathway is not yet fully understood. A study in PNAS by Dick et al. takes us a step closer to that goal by showing that HIV Gag can discriminate between membranes with different cholesterol and fatty acid compositions, thereby helping to explain how viral assembly can be targeted to lipid rafts on the PM (4).
Uncertainty avoidance and facework: A test of the Hofstede model☆

Abstract This study tested whether Hofstede's Uncertainty Avoidance dimension of culture is an important predictor for understanding national differences. To determine this, an analysis of survey data was carried out in six countries: Chile, Hong Kong, Israel, Japan, Sweden and the United States. This replication study tested Hofstede's conclusions of 1980 and 2001 about the role of uncertainty in facework, the action taken to maintain or gain face. As hypothesized, multivariate analysis of covariance (MANCOVA) results showed that, while controlling for social desirability effects, uncertainty avoidance influences ritualistic, harmonious, and aggressive facework strategies in an embarrassing situation. Therefore, this successful replication of Hofstede's assertions as applied to facework confirms that uncertainty avoidance exerts a significant influence on facework communication strategies.
Genetics and morphology of Yaqui chub Gila purpurea, an endangered cyprinid fish subject to recovery efforts☆

Abstract Federally endangered Yaqui chubs Gila purpurea are restricted to the Rio San Bernardino, a small headwater tributary of the vast Rio Yaqui basin of Sonora, Mexico, and Arizona, United States. The species faced almost certain extirpation in the United States during the late 1960s when its remaining habitats went dry. Just prior to that event in 1969, individuals were successfully transplanted into nearby Leslie Creek. Captive propagation was later used to produce fish to re-establish populations in its native range after habitats were reclaimed and protected. We present the history of conservation efforts which include numerous transfers of differing numbers of fish between captive and ‘wild’ stocks. We examined the effects of these recovery efforts on the genetic and phenotypic structure of populations. Genetic and morphological differentiation were respectively assessed using allozyme electrophoresis and principal components analysis. Considerable genetic stability was indicated, with observed variations attributable to documented or inferred changes in population sizes. Morphology also remained uniform, both temporally and spatially, with no evidence of changes attributable to recovery manipulations or ecophenotypic responses to novel environments. Yaqui chubs exhibit high fecundity and quickly establish large effective population sizes, life history characteristics which likely account for the minimal effects of population manipulations.
1,1′,1′′‐[(5RS,6RS)‐6‐Hydroxy‐6‐methyl‐3,4,5,6‐tetrahydro‐2H‐pyran‐3,3,5‐triyl]triethanone

In the title compound, C12H18O5, the ring has a chair conformation, with endocyclic torsion angle magnitudes in the range 47.7 (3)–66.7 (2)°. The OH group donates an inter­molecular hydrogen bond to a C=O group with an O⋯O distance of 2.791 (3) A, forming chains.
SIMULATION OF SPATIAL AND TEMPORAL CHANGES IN WATER QUALITY WITHIN A HYDROLOGIC UNIT

Water quality must be considered in the development and planning aspects of water resource management. To accomplish this, the decision-maker needs to have at his disposal a systematized procedure for simulating water quality changes in both time and space. The simulation model should be capable of representing changes in several parameters of water quality as they are influenced by natural and human factors impinging on the hydrologic system. The objective of this work is two-fold. The first goal is to demonstrate the feasibility of developing and utilizing a water quality simulation model in conjunction with a hydrologic simulation model. The model represents water quality changes in both time and space in response to changing atmospheric and hydrologic conditions and time-varying waste discharges at various points in the system. This model has been developed from and verified with actual field data from a prototype system selected for this purpose. The second aim is to set forth procedural guidelines to assist in the development of water quality simulation models as tools for use in the quality-quantity management of a hydrologic unit.
Cardiomyopathy Mutations in Actomyosin: A Tertiary Structure Dynamics Approach within an in Silico Optical Trap Experiment

Despite great success in simulating protein energetics, molecular dynamics approaches are currently too computationally intensive for use in studying supramolecular actomyosin assemblies. Here tertiary structure coarsegraining strategies are developed to create low-dimension potential functions (Tertiary Structure Models, or TSM) from MD-generated statistical potentials. The effect of domain selection is probed through comparison of successively finer coarsening, beginning with a 4-domain (lever-arm + converter, upper 50k, lower 50k, and n-terminal) TSM. In an attempt to discern and reproduce the basic characteristics of the power stroke the TSM is parameterized for the pre- and post-powerstroke states based on the scallop crystal structures 1qvi and 2ovk, respectively.A first implementation of this approach to study the mechanical effect of mutations in the myosin actin-binding regions is presented in a rigid-body dynamics simulation of domain motion within an in silico optical trap experiment. Both the S532P and R403Q mutations to the myosin S1 are known to cause cardiomyopathy. It is known that the S532P mutation in the lower 50k domain decreases step size from wild-type while the R403Q mutation shows no difference with wild-type within the optical trap experiment. The differential effect of two mutations both occurring in the actin-binding regions is probed within simulation through alterations to the binding parameters of the upper 50k and lower 50k domains with actin. The ability of the TSM model to capture these fundamental results is used as a validation of the approach.
Limit laws for sums of products of exponentials ofiid random variables

We study limit laws for sums of products of exponentials of nonnegative,iid random variables {V ij }, namely $$\sum _{i = 1}^{N(n)} e^{\beta \sum _{j = 1}^n V_{ij} } $$ . Under a Cramer type condition,E[e sV ij ] 0, a weak law of large numbers, central limit theorem, and convergence to stable laws is established for appropriate rates of growth ofN(n) and proper normalizations and scalings.
Equatorial Mid‐Tropospheric Easterly Jet over the eastern Pacific: Comparison from the ECMWF and NCEP‐NCAR reanalyses

[1] The upper-air data set of the European Centre for Medium-Range Weather Forecasts (ECM) 1979–93 Reanalysis is evaluated in comparison to the National Centers for Environmental Prediction-National Center for Atmospheric Research (NCP) Reanalysis for the same period. Attention is focused on the Equatorial Mid-Tropospheric Easterly Jet (EMTEJ) over the eastern Pacific, first noted from a short series of rawin soundings at Galapagos, and then corroborated in its broad spatial context from the NCP 40-year Reanalysis. The present follow-up study contributes a comparison of evidence from the two sources with different model assimilations. The major characteristics of the EMTEJ are confirmed, although the winds from ECM are overall slower and those from NCP faster than the measurements over Galapagos. In both ECM and NCP the easterly speed maximum along the equator is over the eastern Pacific located around 600–700 mb and further westward at progressively lower elevations. Divergence prevails in the realm of the speed maximum and is primarily fed by subsidence from aloft. The ECM evidence differs from NCP by a more westward location of the easterly speed maximum and overall weaker flow.