cssi/SciSciGPT-SciSciNet huggingface dataset:
Synthesis of safety controllers robust to unmodeled intermittent disturbances

The synthesis of controllers enforcing safety properties is a well understood problem for which we have practical algorithms as well as a deep theoretical understanding. This problem is typically formulated as game between the controller seeking to enforce the safety property and the environment seeking to violate it. The solution of these games is given by a winning set: inside the winning set the controller can enforce the desired property as long as it chooses one of the many inputs that forces the system to remain inside the winning set; outside the winning set the environment can violate the winning property independently of the controller's actions. In this paper we answer the following two questions: (1) Among the several inputs available to the controller inside the winning set, are there inputs that are “better” than others? (2) What should the controller do when the state is outside the winning set? In answering these questions we are guided by a desire to be robust to unmodeled intermittent disturbances.
Subcellular distribution of calcium during spermatogenesis of zebrafish, Danio rerio

Calcium plays a variety of vital regulatory functions in many physiological and biochemical events in the cell. The aim of this study was to describe the ultrastructural distribution of calcium during different developmental stages of spermatogenesis in a model organism, the zebrafish (Danio rerio), using a combined oxalate–pyroantimonate technique. Samples were treated by potassium oxalate and potassium pyroantimonate during two fixation stages and examined using transmission electron microscopy to detect electron dense intracellular calcium. The subcellular distribution of intracellular calcium was characterized in spermatogonium, spermatocyte, spermatid, and spermatozoon stages. The area which is covered by intracellular calcium in different stages was quantified and compared using software. Isolated calcium deposits were mainly detectable in the cytoplasm and the nucleus of the spermatogonium and spermatocyte. In the spermatid, calcium was partially localized in the cytoplasm as isolated deposits. However, most calcium was transformed from isolated deposits into an unbound pool (free calcium) within the nucleus of the spermatid and the spermatozoon. Interestingly, in the spermatozoon, calcium was mainly localized in a form of an unbound pool which was detectable as an electron-dense mass within the nucleus. Also, sporadic calcium deposits were scattered in the midpiece and flagellum. The proportional area which was covered by intracellular calcium increased significantly from early to late stages of spermatogenesis. The extent of the area which was covered by intracellular calcium in the spermatozoon was the highest compared to earlier stages. Calcium deposits were also observed in the somatic cells (Sertoli, myoid, Leydig) of zebrafish testis. The notable changes in the distribution of intracellular calcium of germ cells during different developmental stages of zebrafish spermatogenesis suggest its different homeostasis and physiological functions during the process of male gamete development.
An improved Adam Algorithm using look-ahead

Adam is a state-of-art algorithm to optimize stochastic objective function. In this paper we proposed the Adam with Look-ahead (AWL), an updated version by applying look-ahead method with a hyperparameter. We firstly performed convergence analysis, showing that AWL has similar convergence properties as Adam. Then we conducted experiments to compare AWL with Adam on two models of logistic regression and two layers fully connected neural network. Results demonstrated that AWL outperforms the Adam with higher accuracy and less convergence time. Therefore, our newly proposed algorithm AWL may have great potential to be widely utilized in many fields of science and engineering.
Princesses, Princes, and Superheroes: Children's Gender Cognitions and Fictional Characters

The goal of the present study was to identify whether children recognize the gender stereotypes prevalent within the increasingly popular princess, prince, and superhero characters. Interviews with...
Crystallization-Induced Fouling during Boiling: Formation Mechanisms to Mitigation Approaches

Boiling is significantly altered by the presence of dissolved salts. In particular, salts whose solubility decreases with temperature have the tendency to crystallize and adhere to the heat transfer surface and adversely affect the thermal performance. Scaling due to the precipitation of such salts poses serious operational and safety challenges in several practical applications, including heat exchangers, pipelines, and desalination. Here, we study the effect of dissolved salts on the dynamics of pool boiling and its impact on the heat transfer coefficient and critical heat flux (CHF). We find that even undersaturated conditions can lead to crystallization and scale buildup on the boiling surface and dramatically lower heat transfer performance. For example, the CHF for a salt solution that is 75% of the saturation concentration is found to be at least 2 times lower than that for deionized water. Using simultaneous high-speed optical and infrared imaging, we determine the interdependence between crystall...
Nonlinear Surface Waves in One Dimension

In this chapter, we present some examples of nonlinear evolution equations in one space dimension. We re-discuss the traditional Korteweg–de Vries (KdV) equation for the shallow water long channel case, and its cnoidal waves and soliton solutions. Then we briefly present the MKdV equation and some nonlinear dispersion extension of it. In the last sections, we discuss some possible dynamical generalizations of the shallow water models on compact intervals, for any depth of the fluid. The resulting equation is an infinite-order differential one, and it reduces to a finite difference differential equation. We show that this generalized KdV equation approaches the KdV, MKdV, and Camassa–Holm limiting equations, both at the equation and at the solution level, in the appropriate physical conditions. In the last part we discuss the Boussinesq equations on a circle.
Modeling hydrologic connectivity and virtual fish movement across a large Southeastern floodplain, USA

Lateral hydrologic connectivity between a river and its floodplain is important for exchanges of organisms and materials that support healthy, functioning riverine ecosystems. We use a GIS-based distance, cost-weighted spatial model to measure the possible pathways and travel durations for fish migrating from a mainstem river channel to ten different floodplain lakes during a range of discharge magnitudes. We modeled routes of movement and fish swim times for five discharges that ranged from 140 to 1585 m3 s−1 and represented a gradient of hydrologic connectivity. Hydrologic travel pathways included perennial floodplain channels (tributaries and permanent lakes) and intermittently active floodplain channels (channels re-occupying abandoned meander segments, meander-scrolls, batture channels, and crevasses). The different hydrologic pathways made available during the different discharge magnitudes were represented using spatially-variable, raster-based cost surfaces. Fish swim times and route of movement varied with discharge magnitude and lake location. Two distinct patterns emerged between the fish swim times and routes of movement. One group of five floodplain lakes experienced very little change in the route or rate of fish movement with increasing discharge, while another group of five lakes exhibited significant decreases in swim time with increasing discharge. These responses indicate the importance of managing for flood pulses of various magnitudes that hydrologically connect the river and floodplain through different pathways, enabling dynamic spatial and temporal exchanges of organisms and materials.
Constraints on Brain Size: The Radiator Hypothesis

The radiator hypothesis focuses on differential effects that natural selection had on the vascular physiology of hominins that occupied separate niches and the consequences for brain evolution in Paranthropus, Australopithecus, and Homo. Comparative studies of emissary foramina suggest that the network of cranial veins of the australopithecine ancestors of Homo began to increase in complexity in response to temperature constraints associated with occupying niches in thermally stressful habitats. This venous network subsequently became elaborated in Homo in conjunction with increasing brain size. Because physiologists have shown that emissary veins participate in selective brain cooling by delivering blood cooled at the head’s surface into the braincase, the radiator hypothesis postulates that the elaborate network of cranial veins contributed to the regulation of brain temperature as it coevolved with brain size during hominin evolution. The radiator hypothesis has been controversial for two basic reasons: First, it has implications for hominin phylogeny, which is always a contentious subject in paleoanthropology. Second, the subject of selective brain cooling in humans has been controversial within the physiological community. New findings are discussed that bear on selective brain cooling and the radiator hypothesis.
The TRAC-PF1/MOD1 Computer Code

The Transient Reactor Analysis Code (TRAC) is an advanced best-estimate systems code for analyzing LWR accidents. It is being developed at the Los Alamos National Laboratory under the sponsorship of the Reactor Safety Research Division of the US Nuclear Regulatory Commission. A preliminary TRAC version consisting of only one-dimensional components was completed in December 1976. This version was not released publicly nor formally documented. However, it was used in the TRAC-P1 development and formed the basis for the one-dimensional loop component modules. The first publicly released version was TRAC-P1, completed in December 1977. It is described in the Los Alamos report LA-7279-MS.
Desire or Disease? Framing Obesity to Influence Attributions of Responsibility and Policy Support.

The way we describe health threats affects perceptions of severity and preferred solutions to reduce risk. Most people agree obesity is a problem, but differ in how they attribute responsibility fo...
High strength fiber reinforced composites with surface fibrilized aramid fibers

Debonding of the fiber-matrix interface is a common issue in composites, especially for aramid fiber reinforced composites due to their smooth and inert surface. Here, a novel surface treatment is developed for aramid fibers in order to enhance the interfacial properties in composites while preserving the fiber's tensile strength. The fibrilization approach follows the recent work on the aramid nanofibers and uses a solution of potassium hydroxide and dimethyl sulfoxide at room temperature. This process is performed to exfoliate the surface fibrils such that a pseudo-wiskerized fiber is prepared, which provides mechanical interlocking with the matrix. The surface bound fibrils also contain increased polar functional groups, which additionally provides improved wetting due to the enhanced compatibility of the fiber with the matrix as well as offering reactive sites to allow covalent bonding with the reactive thermosets such as epoxy. It is shown that the surface fibrilized fibers possess an 128% improved interfacial shear strength with an epoxy matrix, as well as a 62% increased short beam strength, compared with untreated fiber reinforced composites. The tensile strength of the treated fibers is demonstrated to be preserved, ensuring a significant improvement in the common failure modes without a degradation of in-plane properties. The results indicate the potential of this treatment as a simple, fast, and cost-effective method to improve not only the interface in the aramid fiber reinforced polymer matrix composites but also the bulk laminated composite.
Impact of Inferior Venae Cava Assessment in Tetralogy of Fallot

Abstract Background Inferior vena cava (IVC) size and collapsibility provide a noninvasive estimate of right heart filling pressures, an important determinant of right heart hemodynamic performance that is not measured by cardiac magnetic resonance imaging (CMRI). We hypothesized that compared with CMRI risk model alone, a combined CMRI-IVC risk model will have better correlation with disease severity and peak oxygen consumption in patients with tetralogy of Fallot (TOF). Methods We performed a retrospective review of patients with TOF with moderate/severe pulmonary regurgitation who underwent CMRI and echocardiography. A CMRI risk model was constructed using right ventricular (RV) end-diastolic volume index, RV end-systolic volume index, RV ejection fraction, and left ventricular ejection fraction. We added IVC hemodynamic classification to the CMRI indices to create CMRI-IVC risk model, and IVC hemodynamics were modeled as a categorical variable: normal vs mild/moderately abnormal (dilated IVC or reduced collapsibility) vs severely abnormal IVC hemodynamics (dilated IVC and reduced collapsibility). We defined disease severity as atrial arrhythmias, ventricular arrhythmias, and heart failure hospitalization. Results Of 207 patients, 131 (63%), 72 (35%), and 4 (2%) had normal, mild/moderately abnormal, and severely abnormal IVC hemodynamics, respectively. Compared with the CMRI risk model, the CMRI-IVC risk model had a better correlation with disease severity (area under the curve, 0.62; 95% confidence interval, 0.51-0.74 vs area under the curve 0.84, 95% confidence interval, 0.78-0.91, P = 0.006) and peak oxygen consumption (r = 0.35, P = 0.042 vs r = 0.43, P = 0.031, Meng test P = 0.026). Conclusions The combined CMRI-IVC risk model had a better correlation with disease severity compared with CMRI indices alone and can potentially improve risk stratification in the population with TOF.
Posttraumatic Stress Disorder in Children 6 and Under: A Comprehensive Review of the New Diagnosis

Research has shown that a significant number of young children will experience a traumatic event at some point during their lifetime. These experiences have also been shown to lead to negative reactions and adverse outcomes if not properly addressed and treated. Sometimes individuals who experience these traumatic events develop posttraumatic stress disorder (PTSD); however, concern about the under-diagnosis of PTSD in young children has only recently led to the creation of a subtype specifically for children ages six and under. This paper reviews and critically evaluates the Diagnostic and Statistical Manual of Mental Disorders’ (5th ed.; DSM-5; APA, 2013) novel PTSD subtype and empirical research supporting this new addition. Additionally, this paper summarizes empirical findings regarding the presentation of PTSD in young children and highlights areas for future research. Keywords: childhood trauma, DSM-5, posttraumatic stress disorder
Prevalence of Multimorbidity among Asian Indian, Chinese, and Non-Hispanic White Adults in the United States

Asian Americans are the fastest-growing minority group in the United States, yet little is known about their multimorbidity. This study examined the association of Asian Indians, Chinese and non-Hispanic whites (NHWs) to multimorbidity, defined as the concurrent presence of two or more chronic conditions in the same individual. We used a cross-sectional design with data from the National Health Interview Survey (2012-2017) of Asian Indians, Chinese, and NHWs (N = 132,666). Logistic regressions were used to examine the adjusted association of race/ethnicity to multimorbidity. There were 1.9% Asian Indians, 1.8% Chinese, and 96.3% NHWs. In unadjusted analyses (p < 0.001), 17.1% Asian Indians, 17.9% Chinese, and 39.0% NHWs had multimorbidity. Among the dyads, high cholesterol and hypertension were the most common combination of chronic conditions among Asian Indians (32.4%), Chinese (41.0%), and NHWs (20.6%). Asian Indians (AOR = 0.73, 95% CI = (0.61, 0.89)) and Chinese (AOR = 0.63, 95% CI = (0.53, 0.75)) were less likely to have multimorbidity compared to NHWs, after controlling for age, sex, and other risk factors. However, Asian Indians and Chinese were more likely to have high cholesterol and hypertension, risk factors for diabetes and heart disease.
SIMBA: Single RF Chain Multi-User Beamforming in 60 GHz WLANs

Multi-user transmission in 60 GHz Wi-Fi can achieve data rates up to 100 Gbps by multiplexing multiple user data streams. However, a fundamental limit in the approach is that each RF chain is limited to supporting one stream or one user. To overcome this limit, we propose SIngle RF chain Multiuser BeAmforming (SIMBA), a novel framework for multi-stream multi-user downlink transmission via a single RF chain. We build on single beamformed transmission via overlayed constellations to multiplex multiple users’ modulated symbols such that grouped users at different locations can share the same transmit beam from the AP. For this, we introduce user grouping and beam selection policies that span tradeoffs in data rate, training and computation overhead. We implement a programmable WLAN testbed using software-defined radios and commercial 60-GHz transceivers and collect over-the-air measurements using phased array antennas and horn antennas with varying beamwidth. We find that in comparison to single user transmissions, SIMBA achieves 2× improvement in aggregate rate and two-fold delay reduction for simultaneous transmission to four users.
Probing coordinated co-culture cancer related motility through differential micro-compartmentalized elastic substrates

Cell development and behavior are driven by internal genetic programming, but the external microenvironment is increasingly recognized as a significant factor in cell differentiation, migration, and in the case of cancer, metastatic progression. Yet it remains unclear how the microenvironment influences cell processes, especially when examining cell motility. One factor that affects cell motility is cell mechanics, which is known to be related to substrate stiffness. Examining how cells interact with each other in response to mechanically differential substrates would allow an increased understanding of their coordinated cell motility. In order to probe the effect of substrate stiffness on tumor related cells in greater detail, we created hard–soft–hard (HSH) polydimethylsiloxane (PDMS) substrates with alternating regions of different stiffness (200 and 800 kPa). We then cultured WI-38 fibroblasts and A549 epithelial cells to probe their motile response to the substrates. We found that when the 2 cell types were exposed simultaneously to the same substrate, fibroblasts moved at an increased speed over epithelial cells. Furthermore, the HSH substrate allowed us to physically guide and separate the different cell types based on their relative motile speed. We believe that this method and results will be important in a diversity of areas including mechanical microenvironment, cell motility, and cancer biology.
Forecasting the Frequency of Changes in Quoted Foreign Exchange Prices with the Autoregressive Conditional Duration Model

This paper applies the Autoregressive Conditional Duration model to Foreign Exchange quotes arriving on Reuter's screens. The Autoregressive Conditional Duration model, proposed in Engle and Russell (1995), is a new statistical model for the analysis of data that do not arrive in equal time intervals. When Dollar/Deutschmark data are examined, it is clear that many of the price quotes carry little information about the price process, as they are simply repeats of the previous quote. By selectively thinning the sample, we develop a measure and forecasts for the intensity of price changes. This measure is related to standard measures of volatility but is formulated in a way that better captures the irregular sampling intervals that are inherent to high frequency financial data. Continuous-stochastic-process theorems for crossing times are used to derive an exact relationship between the intensity of price changes and standard volatility measures. The model might be useful for traders and allows tests that other variables are useful in forecasting the intensity of price changes. Generally, little support is found for price leadership, but other variables influence the intensity of price changes.
Inhibition and Synergistic Effect of Mixtures of Oxygen- containing Organic Compounds with Sodium Dodecyl Benzene Sulfate on Steel Rebar Corrosion in 3.5%NaCl Saturated Ca(OH)_2 Solution

The inhibition and synergistic effect of three kinds of oxygen-containing organic compounds(i.e. sorbitol, glucose and ascorbic acid) with sodium dodecyl benzene sulfate(SDBS) on the corrosion of steel rebar in 3.5%NaCl(mass fraction) saturated Ca(OH)2 solution were investigated using linear polarization, potentiodynamic polarization and electrochemical impedance spectroscopy(EIS) techniques. Then the relevant mechanism of the corrosion inhibition and synergistic effect was discussed in terms of quantum chemical calculations and hard and soft acids and bases(HSAB) principle. The results indicated that the inhibition efficiency of the oxygen-containing compounds increased in the follow order: sorbitolglucoseascorbic acid, the highest inhibition efficiency of 96.9% was obtained for the inhibitor ascorbic acid, and had a positive correlation with their absolute hardness as Lewis bases in alkaline chloride solution. A significant synergistic effect appeared when three organic compounds mixed with SDBS in different portions, however, the syn-ergistic effect of sorbitol with SDBS was the strongest.
Developmental window of vulnerability to white matter injury driven by sublethal intermittent hypoxemia.

BACKGROUND In the developing brain, the death of immature oligodendrocytes (OLs) has been proposed to explain a developmental window for vulnerability to white matter injury (WMI). However, in neonatal mice, chronic sublethal intermittent hypoxia (IH) recapitulates the phenotype of diffuse WMI without affecting cellular viability. This work determines whether, in neonatal mice, a developmental window of WMI vulnerability exists in the absence of OLs lineage cellular death. METHODS Neonatal mice were exposed to cell-nonlethal early or late IH stress. The presence or absence of WMI phenotype in their adulthood was defined by the extent of sensorimotor deficit and diffuse cerebral hypomyelination. A separate cohort of mice was examined for markers of cellular degeneration and OLs maturation. RESULTS Compared to normoxic littermates, only mice exposed to early IH stress demonstrated arrested OLs maturation, diffuse cerebral hypomyelination, and sensorimotor deficit. No cellular death associated with IH was detected. CONCLUSIONS Neonatal sublethal IH recapitulates the phenotype of diffuse WMI only when IH stress coincides with the developmental stage of primary white matter myelination. This signifies a contribution of cell-nonlethal mechanisms in defining the developmental window of vulnerability to diffuse WMI. IMPACT The key message of our work is that the developmental window of vulnerability to the WMI driven by intermittent hypoxemia exists even in the absence of excessive OLs and other cells death. This is an important finding because the existence of the developmental window of vulnerability to WMI has been explained by a lethal-selective sensitivity of immature OLs to hypoxic and ischemic stress, which coincided with their differentiation. Thus, our study expands mechanistic explanation of a developmental window of sensitivity to WMI by showing the existence of cell-nonlethal pathways responsible for this biological phenomenon.
Micro-cantilever beam experiments and modeling in porous polycrystalline UO2

Abstract Understanding the impact of microstructure on the thermo-mechanical behavior of oxide nuclear fuels is vital to predicting their performance through multiscale models. Evaluating the mechanical properties at the sub-grain length scale is key to developing these multiscale models. In this work, 3D finite element (FE) models were constructed to simulate the micrometer-scale bending of micro-cantilever beams fabricated using porous polycrystalline uranium dioxide (UO2) and tested at room temperature. The results showed that the porosity and elastic anisotropy of individual grains can play a significant role in determining the effective mechanical properties of the material deduced from the tests. Specifically, the porosity had a non-negligible effect, given that the pore size was of the same order of magnitude as the dimensions of the micro-beams. Correlations between load-deflection data, pore location, and elastic properties (effective Young's modulus) were investigated using UO2 micro-beam FE models, where pore clusters were included and placed at different locations along the length of the beam. Results indicated that the presence of pore clusters near the substrate, i.e., the clamp of the micro-cantilever beam, has the strongest effect on the load-deflection behavior, with the porosity leading to a reduction of stiffness that is the largest for any location of the pore clusters. Furthermore, it was also found that pore clusters located towards the middle of the span and close to the end of the beam have a comparatively small effect on the load-deflection behavior. Therefore, it is concluded that accurate estimates of Young's modulus can be obtained from micro-cantilever experiments after accounting for porosity on the one third of the beam length close to the clamp. This, in turn, provides an avenue to improve microscale experiments and their analysis in porous, anisotropic elastic materials.
Dietary patterns in patients with asthma and their relationship with asthma-related emergency room visits: NHANES 2005-2016.

RATIONALE Extensive interdependencies exist between dietary intake, metabolic dysregulation, and asthma; however, the dietary pattern in adults with asthma remains unknown. OBJECTIVES To evaluate the association between dietary patterns and asthma ER visits and explore the effect of the interaction between race and diet on asthma. METHODS Using NHANES data, we compared dietary patterns between adults with asthma with and without asthma-related emergency room (ER) visits in the previous year, and between subjects of different races. The 2015 Healthy Eating Index (HEI-2015) was used to assess alignment between dietary patterns and the 2015-2020 Dietary Guideline for Americans. RESULTS Among 1681 individuals included in the study, 193 reported asthma-related ER visit. Patients with asthma had low fruit and vegetable intake, and a low mean (SE) HEI-2015 score [52.6 (0.53)]. Individuals with asthma-related ER visits had lower vegetable consumption compared to those without (median 0.61 vs. 0.85 cup equivalents). Furthermore, non-Hispanic Blacks (NHB) reported lower amount of vegetable (median cup equivalent 0.58 vs. 0.89) and fruit intake (0.17 vs. 0.39) and had a lower HEI-2015 score (49.9 vs. 52.9) comparing to non-Hispanic Whites. No association was discovered between dietary patterns and ER visits in multivariable analysis, or significant interactions between diet and race in predicting the need for ER visits. CONCLUSIONS Dietary patterns in adult with current asthma are frequently misaligned with current dietary guidelines. Patients with asthma-related ER visits and of NHB race had lower vegetable consumption; however, the associations disappeared in multivariable analysis. The impact of diet on asthma is not straightforward and deserves further investigation. Supplemental data for this article is available online at at www.tandfonline.com/ijas.
Witches Heathens and Shamans: Religious Experience and Gender Identity among Contemporary Pagans in the United States

iv CHAPTER 1: OVERVIEW AND REVIEW OF CURRENT LITURATURE 1 1.a: Vignette 1 1.1: Overview 2 1.2: Defining Neopaganism and Eclectic Paganism 5 1.3: The Study of Religion in Anthropology 7 1.4: Community and Individuality 9 1.5: Language and Power 11 1.6: Feminist Spirituality 13 1.7: Religion in Context 16 CHAPTER 2: METHOD AND DESIGN 19 2.1: Project Design 19 2.2: Anthropological Study and Religious Scholarship 22 2.3: Cultural Relativism and Methodological Agnosticism 26 2.4: Theory and Interpretation 29 CHAPTER 3: RELIGION AS BODILY EXPERIENCE 32 3.1: Introduction 32 3.a: Vignette 33 3.2: Embodied Research, Embodied Religion 34 3.3: Experiencing the World Differently 40 3.b: Vignette 43 3.4: The Body in Nature 46 3.5: Descriptions and Infinite Digression 54 CHAPTER 4: LANGUAGE USE AND MEDIATION OF EXPERIENCE 56 4.1: Introduction 56 4.2: Linguistic Theory and the Negotiation of Experience 58 4.3: Language and Theology 62 4.4: Linguistic Appropriation 66 4.5: From Linguistic Adaptation to Misrepresentation 71 4.6: Speaking Across the Religious Divide 76
Reflections On A Seminal Force In International Accounting

ccounting is a manifestation of several important environmental factors within a country, including economic, educational and political, and, as such, is evolutionary in accordance with those changing social structures. In today‟s ever expanding global economy, the understanding of international aspects of accounting is critical to understanding world events and the way in which they affect our lives. As new nations and new economic powers emerge, continually updated information, including accounting information, is an essential resource for linking an internal accounting system with worldwide systems. Because of the major impact that international accounting has had on countries‟ internal accounting systems, it is important to examine the contributions made by leaders within the profession. For over the past four decades one of the most influential leaders in the field of international accounting has been Dr. Gerhard G. Mueller.
Optical Region Spectrophotometry: Past and Present

In the 1960s and 1970s optical region spectrophotometry achieved the status of a major tool in stellar research. New instrumentation, rotating grating scanners using photomultiplier tubes as detectors, and improved absolute calibrations of Vega made this possible. After this period the use of this technique declined to its near demise at present. The use of Vega as the primary standard has been both a blessing as it is so bright and a curse especially as modeling it correctly requires treating it as a fast rotating star seen nearly pole-on. It may be better to use several stars to define any future absolute calibration. With absolutely calibrated fluxes and Balmer profiles, often Hγ, investigators used the predictions of model atmospheres to find both the effective temperatures and the surface gravities of stars. The fluxes were photometrically calibrated low dispersion spectra with a typical resolution of order 25 A. A typical data set consisted of 10–15 values covering most of the optical spectral region. At present two instrumental projects ACCESS and the ASTRA Spectrophotometer promise, respectively, a new substantially improved absolute calibration of the optical fluxes of several targets and the availability of a considerable amount of well-calibrated optical flux data for use in studies concerned with stellar properties. They jointly promise to revive optical region spectrophotometric studies.
Correspondences of closed submodules

If N is an M-faithful R-module, then there is an order-preserving correspondence between the closed R-submodules of N and the closed Ssubmodules of HomR(M, N), where S = EndRM. There is a considerable body of research dealing with correspondences between the lattice of submodules of an R-module M and the lattice of left ideals of its endomorphism ring S. This literature includes the well-known Morita theory and its generalizations. When a complete correspondence between all submodules and all left ideals fails to hold, one may still ask whether there is a correspondence between designated sublattices of submodules and left ideals. One particular situation that has attracted much attention has been cases when there is a correspondence between the closed (i.e., essentially closed) submodules of M and the closed left ideals of S. It is known that such a correspondence exists when M is a semisimple module (an elementary observation), when M is a free module [2], when M is a nonsingular retractable module satisfying an additional condition [7], and when M is a nondegenerate module [8]. This article began as a search for a conceptual link among these special cases. Eventually, it was realized that a common denominator is the notion of a self-faithful module, a concept first introduced for generators in [6], and recently exploited to good effect in [3], [4] and [5]. The principal contribution of this article is to demonstrate that a natural correspondence of closed submodules with closed left ideals occurs whenever M is a self-faithful module. In fact, taking a cue from the approach in [1], we show more generally in Theorem 1.2 that when N is an M-faithful R-module, then there exists an order-preserving correspondence between the closed R-submodules of M and the closed S-submodules of HomR(M, N), where S = EndRM. Taking N = M then specializes to the self-faithful case. Additional examples of M being self-faithful, and of the desired correspondence holding, occur when M is a quasi-projective retractable module (Proposition 1.2 in [3]) and when M is a polyform retractable module (Corollary 2.3). Of purely technical interest is the fact that the results contained in this paper remain true even over rings which fail to have an identity element. Received by the editors March 7, 1995. 1991 Mathematics Subject Classification. Primary 16S50; Secondary 16D70. ?)1996 American Mathematical Society
Thermodynamic properties of the Pt-Fe system

We determined activity-composition relationships for the Pt-Fe system by equilibrating Fe-oxides with Pt-Fe alloys at temperatures in the range of 1200–1400 °C and oxygen fugacities from 1.6 to 7.7 log units above the iron-wustite (IW) buffer. The system is characterized by strong negative deviations from ideality throughout the investigated temperature range (e.g., γ^(alloy)_Fe <0.02 for X^(alloy)_Fe <0.3). Our data are consistent with an asymmetric regular solution of the form: RTln γ^(alloy)_Fe = [W_(G1)+2(W_(G2)-W_(G1))X^(alloy)_Fe](X^(alloy)_(Pt))^2 where W_(G1) = –138.0 ± 3.3 kJ/mol and W_(G2) = –90.8 ± 24.0 kJ/mol (1σ). Based on experiments at 1200–1400 °C, variations in the activity coefficients at a given composition are consistent with ln γ^(alloy)_Fe(T_1)/ln γ^(alloy)_Fe(T_2)=T_2/T_1. The Pt-Fe alloy composition in equilibrium with a FeO-bearing silicate liquid can be obtained from: log_(10)f_(O_2) = log{exp[lna^(liq)_(Fe2SiO4) - lna^(liq)_Si)2 - 2 lna^(alloy)_(Fe) -(-ΔG^(0)_(r)/RT)]} where ΔG^(0)_(r) is the standard state free energy for the reaction 2Fe^(alloy) + O_2 + SiO^(liq)_2 = Fe_(2)SiO^(liq)_4. We obtained values of a^(alloy)_(Fe) from our model and used the program MELTS together with the thermodynamic properties of these elements to evaluate activities of SiO_2 and Fe_(2)SiO_4 components in the liquid and ΔG^(0)_(r). We provide sample calculations showing how to predict the optimum Fe concentrations for pre-saturation of Pt-bearing containers to reduce Fe loss from the charge during experiments on magmatic liquids at high temperatures and pressures from 1 atm to 40 kbar.
Editorial: Peer Reviewers Make it All Possible at Clinical Orthopaedics and Related Research ®

T he year 2015 was a stormy one in biomedical publishing. A peer-review fraud ring resulted in the retraction of hundreds of manuscripts from dozens of journals [5]. A major medical journal fired an editor (and a peer reviewer) [2] for suggesting to an author group that their paper would benefit from adding male authors to its roster [3]. And yet-another fake-article scandal came to light, this latest one involving a paper entitled ‘‘Cuckoo for Cocoa Puffs? The Surgical and Neoplastic Role of Cacao Extract in Breakfast Cereal.’’ Created by a random-text generator and putatively authored by Pinkerton LeBrain and Orson Welles, this paper managed to slip by the referees at numerous open-access scientific journals [4, 6]. Major media outlets covered all of these stories, suggesting that they indeed are high-profile events and not mere riffles in the backeddies of science’s main stream. In fact, Clinical Orthopaedics and Related Research received several papers associated with the reviewer-fraud ring [1], but we quickly detected and rejected all of them. Identifying the faux reviews was easier here than at many other journals because their poor quality stood out as anomalous among the first-rate analyses that CORR’s peer reviewers send us every day; the fraudsters’ slipshod work was easy to identify. In the wake of these events, we at CORR remain ever more grateful to our peer reviewers. This was another busy year here, and more than 1500 reviewers helped us to get the science right. Their contributions are the bedrock of our Journal’s quality; nothing here is possible without their considerable efforts. And once again, we especially thank those select few whose efforts earned them spots on our ‘‘Top Reviewer’’ lineup. The ‘‘Top Reviewer’’ roster reflects extraordinary commitment as well as high-quality work. To make this list, a referee needed to complete four or more reviews between September 2014 and August 2015, and to have an average review score in the ‘‘excellent’’ range. This list represents about 3% of those who reviewed for us last year. We thank all our reviewers for their considerable contributions, and we congratulate the ‘‘Top Reviewers’’ for their particular accomplishment in an Acknowledgement at the end of this issue (DOI 10.1007/s11999-015-4574-5). The world of biomedical publishing may be turbulent, but because of the efforts of our reviewers, CORR continues to hit new highs. In 2015, our Journal saw increases in its 5-year Impact Factor, Eigenfactor, and Immediacy Index; we also are on track to far surpass our previous best mark—set in 2014—in article downloads, at about 2 million for the calendar year. Peer reviewers make it all possible.
Deficient repair of DNA lesions in Alzheimer's disease fibroblasts

DNA strand breaks, resulting from treatment with N-methyl-N'-nitro-N-nitrosoguanidine, were repaired more slowly in four strains of familial Alzheimer's disease fibroblasts than in five strains of fibroblasts from age-matched normals. These results were not due to differences between the two cell types in in vitro ages, in the initial DNA damage or in drug-induced cell lysis. Bleomycin-induced DNA double-strand breaks were repaired equally efficiently by both types of cells. Alzheimer's disease cells may have a DNA repair defect, which may be involved in the pathogenesis of this disease.
Frame indifferent formulation of Maxwell’s elastic-fluid model and the rational continuum mechanics of the electromagnetic field

Abstract We show that the linearized equations of the incompressible elastic medium admit a ‘Maxwell form’ in which the shear component of the stress vector plays the role of the electric field, and the vorticity plays the role of the magnetic field. Conversely, the set of dynamic Maxwell equations are strict mathematical corollaries from the governing equations of the incompressible elastic medium. This suggests that the nature of ‘electromagnetic field’ may actually be related to an elastic continuous medium. The analogy is complete if the medium is assumed to behave as fluid in shear motions, while it may still behave as elastic solid under compressional motions. Then the governing equations of the elastic fluid are re-derived in the Eulerian frame by replacing the partial time derivatives by the properly invariant (frame indifferent) time rates. The ‘Maxwell from’ of the frame indifferent formulation gives the frame indifferent system that is to replace the Maxwell system. This new system includes terms already present in the classical Maxwell equations, alongside terms that are the progenitors of the Biot–Savart, Oersted–Ampere’s, and Lorentz-force laws. Thus, a frame indifferent (truly covariant) formulation of electromagnetism is achieved from a single postulate: the electromagnetic field is a kind of elastic (partly liquid, partly solid) continuum.
Chronopotentiometry of the silver-silver sulfide system

Summary It is shown that anodic chronopotentiometry in alkaline solutions with the silver-silver sulfide electrode may be used for determination of sulfide ion concentration over the range, 10 −3 to 10 −2 M , with a precision of 1–2%. The technique is unaffected by pH or the presence of chloride ions. Analysis of chronopotentiometric waves shows that the interfacial reaction behaves like an irreversible one.
Longitudinal variations in the efficacy of lateral giant fiber to giant motor neuron transmission in intact earthworms

Abstract 1. 1. Non-invasive electrophysiological recording methods have been used to characterize segmental variations in transmission between the lateral giant fiber (LGF) and segmentally arranged giant motor neurons (GMN2) in earthworms. 2. 2. LGF-GMN2 transmission is most effective in the first 30 segments of the animal, where usually a pair or occasionally a single LGF spike is sufficient to trigger a GMN2 spike. 3. 3. The efficacy of LGF-GMN2 transmission diminished along an anterior to posterior gradient, with least effective transmission occurring between segments 91 and 120. 4. 4. When a pair of closely spaced LGF spikes is initiated in the posterior end facilitation of LGF conduction velocity causes a gradual reduction (up to 2 msec) in the LGF interspike interval as the spikes are conducted anteriorly. 5. 5. This reduction in LGF interspike interval, in combination with the marked longitudinal gradient in LGF-GMN2 transmission efficacy, tends to focus GMN2 firing and its associated motor response (longitudinal shortening) into anterior segments which are most vulnerable to attack by predators.
Simulation and analysis of Awerbuch–Peleg and GSM schemes for location tracking of mobile users

Mobile users are increasingly demanding full access to networked communications while they are on the move. Several studies have shown that the overhead incurred by the network to keep track of the current location of mobile users is considerably high. The methods currently used for location tracking incur heavy unnecessary costs by requiring that users update locations in their home networks after each move regardless of the distance at which the move occurs, and that all search attempts for a mobile user are first routed to that user's home network. The Awerbuch–Peleg scheme presents a formal model for location tracking which attempts to minimize the cost of local operations—both move and find operations—through the construction of a regional hierarchy. In this paper we present a performance evaluation of the Awerbuch–Peleg scheme. We also compare its performance to that of the GSM-based location tracking scheme. It is found that the Awerbuch–Peleg scheme in general results in higher costs than the GSM scheme. The reason for this is found to be some unexpected properties of the read and write sets which are key components of the Awerbuch–Peleg scheme. Copyright © 2001 John Wiley & Sons, Ltd.
Optimizing the antibacterial activity of a lead structure discovered by "SAR by MS" technology.

Abstract We report on lead optimization of a compound that was originally discovered to bind bacterial 23S rRNA near the L11 binding site and inhibit translation in vitro, but lacked detectible antibacterial activity. In this study, we were able to generate compounds with antibacterial activity against Gram-negative and Gram-positive pathogens, including a methicillin-resistant S. aureus strain.
Trimethyltin ototoxicity in albino rats

The toxicity of alkyltin compounds is of exceptional interest due to the dissimilar toxic effects of some very closely related structural analogues among this class of compounds. Since several features of the toxicity of trimethyltin appeared to be consistent with a mechanism involving accumulation of the toxicant on melanin pigments, the ototoxicity induced by TMT exposure was examined in albino rats. Hearing thresholds for tones sampling the mid- and high-frequency range of the rat's audibility function were assessed by reflex inhibition audiometry. TMT produced a frequency dependent loss of auditory sensitivity that was most severe in the high frequency range. The TMT-induced impairment of auditory function was similar to that previously observed in pigmented Long-Evans rats. These results extend the observation of TMT-induced hearing loss to a non-pigmented rodent strain and suggest that the accumulation of TMT on cochlear melanin is not critical to the production of hearing impairment by TMT.
A natural language front-end for knowledge acquisition

Knowledge Acquisition has historically been a bottleneck in the development of knowledge based systems. While efficient and powerful techniques have been developed for knowledge representation and processing, transferring knowledge from the problem domain into the knowledge base is characterized by the inordinate effort required by knowledge engineers; a lack of any substantial automation of the knowledge acquisition process; and in particular, the difficulty and undue complexity of the knowledge acquisition interfaces for many knowledge based systems. This paper proposes a Natural Language Interface or Front-End as a means of effective knowledge acquisition for knowledge based systems. This would have the advantage of transferring the burden of knowledge acquisition from the user to the system, while providing ease of natural language interaction to the user. By constraining such a front-end to use within limited problem domains, many of the difficulties associated with natural language processing may be avoided, while reaping the benefits of more effective knowledge acquisition. It is also recognized that the knowledge acquisition activity is one that possesses expertise of itself, and using a knowledge acquisition expert system in parallel to this front-end will likely offer further advantages in the development of part or wholly-automated knowledge acquisition.
Improved calculation of fine-structure splittings in the ground state of potassiumlike ions

The fine-structure splitting between the 3p63d2DJ, J = 3/2 and J = 5/2 levels of K-like ions, Ti3+ to U73+, are calculated by means of Dirac–Fock single-configuration and multiconfiguration wave functions. The multi-configuration calculation includes jj configurations arising from some selected nonrelativistic configurations in the M-shell Coulomb complex; these include all the Dirac–Fock configurations with the principal quantum number n = 3, which are degenerate in the pure jj coupling limit for infinite nuclear charge Z, along with other configurations such that the calculated energy is correct to order Z2 and Z asymptotically. The difference between known experimental and calculated multiconfiguration Dirac–Fock fine-structure splittings is almost independent of Z, thus allowing us to predict unknown values reliably. From this plot and a comparison of theoretical and experimental results we conclude that the observed fine-structure splitting of Ag28+ [ J. Opt. Soc. Am. B2, 1661 ( 1985)] is too small. We present splittings in high-Z K-like ions for which experimental values are unknown.