cssi/SciSciGPT-SciSciNet huggingface dataset:
Numerical Study of a Viscous Fluid Flow past a Circular Cylinder

A systematic numerical study of the unsteady viscous incompressible fluid flow past a circular cylinder is reported. The range of the Reynolds number considered is 1 to 100. The steady state solutions could be obtained at the Reynolds numer R =10, 20, 30, 40, 50 as the limit of the unsteady state solutions. The numerical results are compared with those for the steady problem and they are found to be in agreement. Dependence of the flow pattern, vorticity distribution, pressure distribution and the drag are shown on the Reynolds number and the time.
Analyzing Limited Size Archivers of Multi-objective Optimizers

In the context of multi-objective optimization, where there may be many optimal incomparable solutions, most of the optimizers maintain a limited repository, to keep the objective vectors of the solutions found during the execution. There are several methods to decide which vectors remain in that limited size archive, and these different techniques may have properties that guarantee the diversity and quality of their outcomes. This paper examines some of those strategies, analyzing their properties, and comparing empirically their outputs based on two quality indicators, additive epsilon and hyper volume. Most of the archiving techniques studied in this work cannot ensure that at the end of the process their vectors are all optimal. Due to this fact, a new approach is presented, based on a second archive to store the points which would be discarded. The main idea is verify how much the recycled vectors could improve the generated set. In the realized tests, the method had not a significant time cost regardless the adopted archiving technique.
Model Verification and Validation Concepts for a Probabilistic Fracture Assessment Model to Predict Cracking of Knife Edge Seals in the Space Shuttle Main Engine High Pressure Oxidizer

Physics-based models are routinely used to predict the performance of engineered systems to make decisions such as when to retire system components, how to extend the life of an aging system, or if a new design will be safe or available. Model verification and validation (V&V) is a process to establish credibility in model predictions. Ideally, carefully controlled validation experiments will be designed and performed to validate models or submodels. In reality, time and cost constraints limit experiments and even model development. This paper describes elements of model V&V during the development and application of a probabilistic fracture assessment model to predict cracking in space shuttle main engine high-pressure oxidizer turbopump knife-edge seals. The objective of this effort was to assess the probability of initiating and growing a crack to a specified failure length in specific flight units for different usage and inspection scenarios. The probabilistic fracture assessment model developed in this investigation combined a series of submodels describing the usage, temperature history, flutter tendencies, tooth stresses and numbers of cycles, fatigue cracking, nondestructive inspection, and finally the probability of failure. The analysis accounted for unit-to-unit variations in temperature, flutter limit state, flutter stress magnitude, and fatigue life properties. The investigation focused on the calculation of relative risk rather than absolute risk between the usage scenarios. Verification predictions were first performed for three units with known usage and cracking histories to establish credibility in the model predictions. Then, numerous predictions were performed for an assortment of operating units that had flown recently or that were projected for future flights. Calculations were performed using two NASA-developed software tools: NESSUS(Registered Trademark) for the probabilistic analysis, and NASGRO(Registered Trademark) for the fracture mechanics analysis. The goal of these predictions was to provide additional information to guide decisions on the potential of reusing existing and installed units prior to the new design certification.
Dangerous Climates Factors Associated With Variation in Racist Hate Crimes on College Campuses

Although hundreds of American college students are the victims of bias-motivated verbal and physical assaults every year, little research explores whether there is a systematic pattern to the hate ...
The fabrication of replicated optics for hard x-ray astronomy

We describe the fabrication process for producing shallow-graze-angle mirrors for hard x-ray astronomy. This presentation includes the generation of the necessary super-polished mandrels, their metrology, and the subsequent mirror shell electroforming and testing.
Protein synthesis in rabbit reticulocytes. XV: Isolation of a ribosomal protein factor (CO-EIF-1) which stimulates Met-tRNAfMet binding to EIF-1☆

Abstract A protein factor, CO-EIF-1, has been partially purified from the high salt wash of reticulocyte ribosomes. CO-EIF-1, by itself, does not bind Met-tRNA f Met but significantly stimulates (2–3 fold) Met-tRNA f Met binding to EIF-1 and also increases the initial rate of this binding reaction. In the presence of CO-EIF-1, approximately 90 percent of the input EIF-1 (assuming a molecular weight of 140,000) was bound to Met-tRNA f Met .
Thiolate S-oxygenation controls nitric oxide (NO) photolability of a synthetic iron nitrile hydratase (Fe-NHase) model derived from mixed carboxamide/thiolate ligand.

In order to determine the origin of the NO photolability of the active site of Fe-containing nitrile hydratase (Fe-NHase), a model complex of the NO-bound active site (dark form) has been isolated and structurally characterized. The model, NEt4[(Cl2PhPepS)Fe(NO)(DMAP)] (2), is derived from a tetradentate ligand comprising carboxamido N and thiolato S donor centers much like the donors present in the active site of Fe-NHase. This {Fe−NO}6 nitrosyl effectively mimics the NO-bound active site in terms of structural and spectroscopic parameters. However, this model lacks the key property of NO photolability. Interestingly, S-oxygenation of the model complex results in formation of Na[(Cl2PhPep{SO2}2)Fe(NO)(DMAP)] (3), in which the −S donors are oxygenated to −SO2 moieties, and this species exhibits NO photolability. These results indicate that S-oxygenation could be the key reason for the observed NO photolability of the active site of the dark form of Fe-NHase.
Adolescents Seeking Nutrition Information: Motivations, Sources and the Role of the Internet

Much research exploring the potential of the internet for providing effective nutrition information to adolescents focuses on the design of websites and uses of the internet. This study takes a step back to investigate the specific reasons adolescents do and do not use the internet to learn about nutrition. This paper asks, "What motivates adolescents to select the internet when learning about nutrition?" Using in-depth interviews and a survey, two stages of the information-seeking process are examined: initiation and selection. Results reveal that because school classes are serving as a primary entry point for learning about this topic, even personal nutrition needs are often conceptualized as formal and education-related. The internet is less appealing than books and teachers for fulfilling those needs because adolescents primarily use it for social, not formal tasks. The paper concludes that educators should incorporate more directed use of the internet into nutrition classes and assignments.
Müllerian remnants of male mice exposed prenatally to diethylstilbestrol.

Prenatal exposure of males to diethylstilbestrol (DES) results in reproductive tract teratogenesis, ie, retention of Mullerian duct remnants. The potential of these remnants to develop pathological changes has not been studied. Therefore, pregnant outbred CD-1 mice were subcutaneously injected with daily doses of DES (100 μg/kg) on days 9 through 16 of gestation. DES-exposed male offspring and age-matched control male mice were sacrificed at 10 to 18 mo of age and examined for reproductive tract abnormalities. Prominent Mullerian remnants were observed in 268 out of 277 (97%) of the DES-exposed male mice. These remnants differentiated into “femalelike structures” homologous to oviduct and uterus. The Mullerian remnants were often enlarged and cystic and shared supporting connective tissue with adjacent male structures. Previously reported lesions, termed “epididymal cysts,” were determined histologically to be cystic “oviductlike” structures and were, therefore, considered a Mullerian duct abnormality. Pathological changes in these male oviductal and uterine homologs included benign and malignant lesions. In addition, epididymal structures were altered. Inflammation and sperm granulomas were prevalent in DES-treated mice as young as 10 mo old but were only observed in control mice at 18 mos. Cysts of epididymal duct origin, hyperplasia, and adenoma of the epididymal duct were also observed. No comparable abnormalities were noted in 122 control males of corresponding ages. The data presented in this report demonstrated that transplacental exposure to DES affected the differentiation and normal development of the male genital tract involving both the Mullerian (paramesonephric) and Wolffian (mesonephric) ducts. The long-term changes in these tissues include lesions, some of which resembled neoplasia although the natural history of the lesions is not known. Moreover, some previously described abnormalities referred to as “epididymal cysts” were associated with tissues derived from embryonic female origin.
Evaluation of polymer sequence fragment data using graph theory.

Much of recent work to determine primary structures of nucleic acids and proteins employs the “fragmentation” or “overlap” stratagem. Typically, a preparation of a given polymer with unknown sequence is purified and then subjected to an enzyme known to cut the polymer at certain specific sites. The quantities and sequences of the resulting fragments are determined. For RNA primary sequences, pancreatic ribonuclease and T1 ribonuclease are ordinarily used as fragmenting enzymes. A technique is described for evaluating such fragment data. It has the following properties: It is easily determined whether or not the fragment data is inconsistent. It is always possible to determine the first and last nucleotides of the unknown sequence from the data of two limit digests. Consistent data from two limit digests can always be fitted into a convenient conceptual framework developed within the theory of graphs. In most cases, partial digest information can be used to modify the framework constructed from two limit digests, as such information is obtained. An efficient analysis of all fragment data in this conceptual framework can always be made. One can detect inconsistencies and can generate the entire list of polymer sequences consistent with the fragment data.
LUCY: a 3-D pelvic model for surgical simulation.

Abstract Development of 3-D models of human anatomy for use in virtual reality simulators is anticipated to enhance surgical training. These models may be a valuable resource for gaining mastery of minimal-access procedures. The pelvis portion (hip to upper-thigh) of a 32-year-old female cadaver was frozen and sectioned axially in approximately 2-mm increments as the first step in producing an accurately representative 3-D model of the human female pelvis. Photographic exposures of the entire series of 95 sections were then converted to digital format. Adobe PhotoShop masks for each structure were created and converted into wire-frame and surface-textured models; this aggregate model set was named “LUCY.” To date, 3-D representations of 40 pelvic structures (over 2200 individual masks) have been modeled. In conjunction with haptic technology, these virtual anatomic models will enable users to practice fundamental surgical manipulations and procedures such as tubal ligation and ovariectomy. The deployment of surgical-simulation models such as LUCY may facilitate technical-performance aspects of surgical training, particularly those associated with minimal-access procedures. Manipulations and procedures can be practiced over the Internet, providing a host of flexible options to enhance the surgical curricula.
The use of cone beam computed tomography for the assessment of trichorhinophalangeal syndrome, type I – a case report

Trichorhinophalangeal syndrome type I is a rare autosomal dominant disorder characterized by cone-shaped epiphysis, sparse fine hair, pear-shaped nose and variable growth retardation. The typical craniofacial features include thin upper lip, elongated philtrum, large outstanding ears, shortened posterior facial height associated with short mandibular ramus and reduced and superiorly deflected posterior cranial base. This report describes a 17-year-old male patient with trichorhinophalangeal syndrome type I and a detailed description of the craniofacial radiographic findings, including the use of cone beam computed tomography images for determination of the airway and temporomandibular joint discrepancies.
Assembly of the tau of bacteriophage T4

Abstract The formation of bacteriophage T4 has been studied by characterizing the phage components accumulating in cells infected—under restrictive conditions—with mutants blocked at different stages of the assembly process. Three structures which appear to be intermediates in tail assembly have been isolated by centrifugation: baseplates (S20,w ≅ 80 s), core-baseplates (S20,w ≅ 80 s), and core-baseplates with surrounding sheath (S20,w ≅ 130 s). The functions of genes 19, 48 and 54 are required for the conversion of the baseplate to the core-baseplate. The functions of genes 3, 15 and 18 are required for the formation of the sheath. Gene 18 codes for a major structural protein of the sheath. Genes 3 and 15 specify products required for the stabilization and completion of the sheath. Tail assembly is sequenced; the baseplate is completed first and the core forms on the baseplate. The gene 18 product polymerizes on the core-baseplate and then the 3 and 15 gene products fix the sheath subunits in the polymerized form. After sheath formation, a segment appears to be added to the core at the terminus of the sheath, permitting subsequent attachment of the head. The tail fibers attach only after the particle formed by head-tail union has been acted upon by the gene 9 product. Particles which have not been acted upon by the gene 11 or 12 product adsorb to bacteria but do not kill them. Electron microscopic observations on the state of phage heads in mutant lysates are also presented. Mutations in three genes result in the accumulation of head membranes empty of DNA. Phage heads and phage tails are formed independently of each other.
Activation of the cAMP system by medorinone correlates with positive inotropy or vasorelaxation

Medorinone is a structurally novel positive inotropic/vasodilator agent that selectively inhibits cardiovascular low Km cAMP phosphodiesterase (PDE). As inhibitors of this PDE isozyme would be expected to activate the cAMP system, the objectives of the present study were to quantitate changes in cAMP content, activation of cAMP protein kinase (cAPK), and positive inotropy in isolated guinea pig papillary muscles or vasorelaxation in aortic smooth muscle by medorinone. In papillary muscles, positive and significant correlations were evident between isometric force development as a function of cAMP content (r = 0.92; P <0.01) or cAPK activity ratio, an index of activation of cAPK (r = 0.78, P <0.05) for concentrations of medorinone from 1 to 300 μM. Similar correlations were evident in aortic smooth muscles frozen during medorinone-mediated relaxation of phenylephrine contractions (r = 0.89, P <0.05). These correlations and lines of regression were similar to those obtained for milrinone, papaverine, and isoproterenol; the correlation was similar for forskolin while the slope of the regression line was less. The temporal sequence of these events was also quantitated for a concentration of medorinone (100 μM) that produced approximately a 100% increase in papillary muscle isometric force and 90% vasorelaxation. Significant increases in either cAMP content or cAPK activity ratio paralleled increases in force development (papillary muscle) or vasorelaxation (aortic smooth muscle). In summary, these results show that significant increases in cAMP content or cAPK activation are correlated with modulation of cardiac or vascular force by medorinone and thus support the hypothesis that inhibition of the low Km cAMP PDE is a mechanism by which medorinone effects positive inotropy and vasodilation.
Severe Hypoglycemia Predicts Mortality in Diabetes

In this issue of Diabetes Care , McCoy et al. (1) report 3.4-fold higher mortality in patients with diabetes who self-reported severe hypoglycemia (that which required the assistance of another person) 5 years earlier. They suggest that patient-related outcomes such as hypoglycemia would augment risk stratification and management of patients with diabetes. Iatrogenic hypoglycemia is the limiting factor in the glycemic management of diabetes (2). It causes recurrent morbidity in most people with type 1 diabetes and many with advanced type 2 diabetes and is sometimes fatal. It impairs defenses against subsequent hypoglycemia and, thus, causes a vicious cycle of recurrent hypoglycemia. The barrier of hypoglycemia generally precludes maintenance of euglycemia over a lifetime of diabetes and, therefore, full realization of the benefits of glycemic control. Although it can be caused by an episode of marked absolute therapeutic hyperinsulinemia, iatrogenic hypoglycemia is typically the result of the interplay of mild-to-moderate absolute or even relative therapeutic hyperinsulinemia and compromised physiological and behavioral defenses against falling plasma glucose concentrations (2). The compromised physiological defenses include attenuated adrenomedullary epinephrine responses that, in the setting of absent insulin and glucagon responses, cause the clinical syndrome of defective glucose counterregulation with its 25-fold or greater increased risk of severe hypoglycemia during aggressive glycemic therapy. The compromised behavioral defense is the failure to ingest carbohydrates, which results from attenuated sympathoadrenal (largely sympathetic neural) responses that cause the clinical syndrome of hypoglycemia unawareness with its sixfold or greater increased risk of severe hypoglycemia during aggressive glycemic therapy. Defective glucose counterregulation and hypoglycemia unawareness are the components of hypoglycemia-associated autonomic failure (HAAF) in diabetes. HAAF is a form of …
The Cross-Age Mentoring Program: A Developmental Intervention for Promoting Students’ Connectedness across Grade Levels:

In cross-age peer mentoring programs, high school students mentor younger students. Prior research demonstrates the positive effects for mentees as well as for mentors. This context-based, strength...
Whole Language and Representational Theories Helping Children to Build a Network of Associations

—Many professionals are interested in whole language intervention, but are unsure what it “looks like,” what goals and objectives can be addressed in such naturalistic contexts, and what techniques can be used to achieve those goals. These issues become clearer when the speech-language pathologist (SLP)has an understanding of some current theories of language learning and use that are consistent with whole language. This article briefly discusses some of these theories, including lexical contrast, connectionism, schemata, and event representations. As the theories are discussed, direct application is made to intervention, and examples of interactions between SLPs and children are provided.
Acute colonic pseudoobstruction in a child with sickle cell disease treated with neostigmine

Sickle cell disease is a disorder that produces significant morbidity and mortality. Vaso-occlusive pain crises are the most common presenting symptom associated with sickle cell patients. A rare, yet important to recognize, complication of sickle cell disease is acute colonic pseudoobstruction, also known as Ogilvie's syndrome. These patients may present with symptoms that are difficult to distinguish from other etiologies of abdominal pain, but a thorough diagnostic workup can provide important clues. Furthermore, there is no agreement on optimal treatment of pseudoobstruction. We report the first pediatric case of acute pseudoobstruction secondary to sickle cell disease that was treated successfully with neostigmine. Early recognition of this phenomenon is important as it alters patient management, can be treated medically, and may avoid unnecessary surgical intervention.
The Interprofessional Collaborative Practice: Clergypersons and Mental Health Professionals

The purpose of this study is to examine the relationships among variables identified in research literature as obstacles and benefits to interprofessional collaboration-- academic education, interprofessional education, teamwork and communication skills, and trust---as it relates to the participation of clergypersons in interprofessional collaborative practice. The sample consisted of ordained Christian clergypersons in Florida who voluntarily completed a survey questionnaire. Standard and stepwise multiple regression was applied to analyze the data. The model accounts for 25% of the variation of interprofessional collaborative practice. Results also revealed that the education variables explained significantly 20% of the variance of interprofessional collaborative practice.
Fluorescence lifetime measurements in a flow cytometer by amplitude demodulation using digital data acquisition technique

We have developed a method for fluorescence lifetime measurements in a flow cytometer based upon the amplitude demodulation of the fluorescence signals using digital data acquisition techniques. Amplitude demodulation is one of the two methods by which excited state lifetimes may be investigated in the frequency domain. The other method involves the phase-shift measurements. In frequency-domain measurement techniques, the amplitude-demodulation and phase-shift data serve mutually complementary roles to enhance the analytical capabilities of the measurements. The purpose of having amplitude demodulation measurement capability is to obtain information that supplements, rather than replaces, that obtained by the phase-shift method alone. Application of amplitude demodulation measurements has been widely explored in static, cuvette-based, frequency domain systems. However, due to time dependence of the amplitude of the modulated fluorescence signal in a flow cytometer, the amplitude demodulation measurements in flow turns out to be more complicated than similar measurements in a static system. The goal of the present work is to explore the problems involved in amplitude demodulation measurements in flow (using digital method), through detailed theoretical modeling and use the model to develop a practical method that can be incorporated into a flow cytometer to measure amplitude modulation lifetimes. We experimentally verify the amplitude demodulation measurement capability of this method using fluorescent microspheres. The experimental measurements show good agreement with static frequency-domain measurements on microspheres in bulk suspensions.
Estimating the economic value of national parks with count data models using on-site, secondary data: the case of the great sand dunes national park and preserve.

We estimate an individual travel cost model for Great Sand Dunes National Park and Preserve (GSD) in Colorado using on-site, secondary data. The purpose of the on-site survey was to help the National Park Service better understand the visitors of GSD; it was not intended for a travel cost model. Variables such as travel cost and income were estimated based on respondents’ Zip Codes. Following approaches found in the literature, a negative binomial model corrected for truncation and endogenous stratification fit the data the best. We estimate a recreational benefit of U.S. $89/visitor/year or U.S. $54/visitor/24-h recreational day (in 2002 U.S. $). Based on the approach presented here, there are other data sets for national parks, preserves, and battlefields where travel cost models could be estimated and used to support National Park Service management decisions.
Detection of Diffuse Interstellar [O II] Emission from the Milky Way Using Spatial Heterodyne Spectroscopy

Using a newly developed spatial heterodyne spectrometer (SHS), we have obtained the first radial velocity resolved emission-line profiles of diffuse [O II] 3726 and 3729 ? emission lines from the warm (104 K) ionized component of our Galaxy's interstellar medium. These [O II] lines are a principal coolant for this widespread, photoionized gas and are a potential tracer of variations in the gas temperature resulting from unidentified heating processes that appear to be acting within the Galaxy's disk and halo. By spectrally isolating for the first time Galactic [O II] from atmospheric [O II] emission, we were able to detect interstellar [O II] out to 20? from the Galactic equator with intensities that range from tens of rayleighs near the Galactic plane to less than 1 rayleigh at high Galactic latitudes. The [O II] line profiles clearly show structure indicating emission along the lines of sight from both local and more distant interstellar gas. Comparisons of the [O II] intensities with the intensities of [N II] 6584 ? and H? 6563 ? observed with WHAM indicate that the observed variations in [N II]/H? and [O II]/H? in the diffuse interstellar gas are consistent with variations in temperature and confirm the value of the [O II] observations as a temperature diagnostic for the WIM.
A Draw-In Sensor for Process Control and Optimization

Sheet metal forming is one of the major processes in manufacturing and is broadly used due to its high degree of design flexibility and low cost. In the sheet metal forming process, draw-in (planar movement of a sheet periphery) frequently occurs and is one of the most dominated indicators on the success of a forming process. Currently, monitoring and controlling draw-in during each stamping operation requires either time-consuming setup or a significant die modification. Most devices have been used only in laboratory settings. Our goal is to design a draw-in sensor providing high sensitivity in monitoring; ease of setup, measurement and controlling; and eventually be implemented in industry. Our design is based on the mutual inductance principle, which we considered physical factors affecting the characteristics of the draw-in sensor. Two different configurations, single-transducer and double-transducer of our draw-in sensors have been designed and tested. The results showed good linearity, especially for the double-transducer case. The output of the draw-in sensor was affected by the type of sheet metal, dimension of the transducer, and the distance between the transducer and the testing sheet metal. It was found that the result was insensitive to the waviness of the sheet metal if sheet thickness was thin. The invention, implementation, and integration of the draw-in sensor will have an enormous impact on revolutionizing the control of stamping process, will provide solid ground for process variation and uncertainty studies, and ultimately will affect the design decision process.
Role of intracellular Cd2+ in catecholamine release and lethality in PC12 cells

Abstract To evaluate the role of intracellular Cd 2+ in catecholamine release and lethality in rat pheochromocytoma (PC12) cells the following results were obtained: [1] the presence of Cd 2+ intracellularly was demonstrated with the Cd 2+ -sensitive fluorescent dye BTC-5N, [2] Cd 2+ entry through Ca 2+ -channels was either blocked with nifedipine or diltiazem or increased with Bay K8644, [3] Cd 2+ entry through voltage sensitive Ca 2+ channels was related to dopamine release and cell lethality, [4] a calmodulin inhibitor protected against Cd 2+ toxicity, and [5] extracellular Ca 2+ concentration, altered prior to Cd 2+ exposure, was inversely related to dopamine release by Cd 2+ . The data indicate intracellular effects of Cd 2+ rather than cell surface actions are primarily involved in neurotransmitter release and lethality by toxic levels of Cd 2+ in adrenomedullary cells.To evaluate the role of intracellular Cd 2+ in catecholamine release and lethality in rat pheochromocytoma (PC 12) cells the following results were obtained: [1] the presence of Cd 2+ intracellularly was demonstrated with the Cd 2+ -sensitive fluorescent dye BTC-5N, [2] Cd 2+ entry through Ca 2+ -channels was either blocked with nifedipine or diltiazem or increased with Bay K8644, [3] Cd 2+ entry through voltage sensitive Ca 2+ channels was related to dopamine release and cell lethality, [4] a calmodulin inhibitor protected against Cd 2+ toxicity, and [5] extracellular Ca 2+ concentration, altered prior to Cd 2+ exposure, was inversely related to dopamine release by Cd 2+ . The data indicate intracellular effects of Cd 2+ rather than cell surface actions are primarily involved in neurotransmitter release and lethality by toxic levels of Cd 2+ in adrenomedullary cells.
SYNGRAPH: A graphical user interface generator

The SYNGRAPH system automatically generates graphical user interfaces. It generates interactive Pascal programs from a description of the input language's grammar. From the grammar it deduces information about how to manage both physical and simulated devices, and how prompting and echoing are performed. Input errors are detected, and can be corrected using automatically provided rubout and cancel features. The natural integration of application specific semantics into the system is also shown including appropriate semantic recovery from input errors.
Building real-time music tools visually with Sonnet

We are building a variety of interactive music tools using Sonnet, a visual programming language in use at our center. Originally designed for sonification experiments for monitoring and debugging programs, Sonnet has grown into a more general system with a focus on real-time event-driven applications. In this paper, we describe some of the features of Sonnet followed by some examples of how it is being used.
Through the Eyes of the Experts: Meteorologists’ Perceptions of the Probability of Precipitation

AbstractPrior surveys of the public indicated that a variety of meanings and interpretations exist about the probability of precipitation (PoP). Does the same variety of meanings for the PoP exist among members of the professional atmospheric science community? What do members of the professional community think that the public should know to understand the PoP more fully? These questions were examined in a survey of 188 meteorologists and broadcasters. Meteorologists were observed to express a variety of different definitions of the PoP and also indicated a high degree of confidence in the accuracy of their definitions. Differences in the definitions stemmed from the way the PoP was derived from model output statistics, parsing of a 12-h PoP over shorter time frames, and generalizing from a point PoP to a wider coverage warning area. In this regard 43% of the online survey respondents believed that there was no or very little consistency in the definition of PoP; only 8% believed that the PoP definition ...
Holographic Method of Measuring Scintillation Effects

A method is described by which a wavefront-reconstruction technique is utilized to record the effects of a turbulent medium on the propagation of optical beams. By this technique both amplitude and phase information in a two-dimensional cross section of a received optical beam are recorded. The mode structure of the source is not seen to be critical in this application.
Microwave Properties of Ice-Phase Hydrometeors for Radar and Radiometers: Sensitivity to Model Assumptions

A simplified framework is presented for assessing the qualitative sensitivities of computed microwave properties, satellite brightness temperatures, and radar reflectivities to assumptions concerning the physical properties of ice-phase hydrometeors. Properties considered included the shape parameterm of a gamma size distribution and the melted-equivalent mass median diameter D0, the particle density, the dielectric mixing formula, and the choice of complex index of refraction for ice. These properties are examined for selected radiometer frequencies of 18.7, 36.5, 89.0, and 150.0 GHz and radar frequencies at 2.8, 13.4, 35.6, and 94.0 GHz—consistent with existing and planned remote sensing instruments. Passive and active microwave observables of ice particles are found to be extremely sensitive to the D0 of the size distribution. Similar large sensitivities are found for variations in the ice volumefractionwheneverthe geometric massmediandiameter exceeds approximately 1 /8th of the wavelength. At 94 GHz the two-way path-integrated attenuation is potentially large for dense/compact particles. The distribution parameter m has a comparatively weak effect on any observable: less than 1‐2 K in brightness temperature and a maximum of 2.7 dB (S band only) in the effective radar reflectivity. Reversal of the roles of ice and air in the Maxwell Garnett dielectric mixing formula leads to a substantial change in both microwave brightness temperature (;10 K) and radar reflectivity (approximately 2 dB across all frequencies).The choice of the complex indexof refraction of ice can produce a 3%‐4% change in the brightness temperature depression.
Optimal reactive power dispatch of wind power plant cluster considering static voltage stability for low-carbon power system

The implementation of developing the wind power is an important way to achieve the low-carbon power system. However, the voltage stability issues caused by the random fluctuations of active power output and the irrational regulations of reactive power compensation equipment have become the prominent problems of the regions where large-scale wind power integrated. In view of these problems, this paper proposed an optimal reactive power dispatch (ORPD) strategy of wind power plants cluster (WPPC) considering static voltage stability for low-carbon power system. The control model of the ORPD strategy was built according to the wind power prediction, the present operation information and the historical operation information. By utilizing the automatic voltage control capability of wind power plants and central substations, the ORPD strategy can achieve differentiated management between the discrete devices and the dynamic devices of the WPPC. Simulation results of an actual WPPC in North China show that the ORPD strategy can improve the voltage control performance of the pilot nodes and coordinate the operation between discrete devices and the dynamic devices, thus maintaining the static voltage stability as well.
Perspectives on Risk Perceptions

Drawing on the literature from the fields of cognitive and social psychology, sociology, and political science, we discuss perceptions of risks and benefits, the impact of perceptions and personal preferences on choice and behavior, the question of “socially acceptable” thresholds of risk, and the analytic and descriptive means by which such thresholds might be identified. We hypothesize that existing psychometric methods may be adapted for the scaling of perceived benefit. We review factors hampering the application of formal methodologies in the resolution of controversial public debates, and express doubt about the identification of a socially acceptable threshold of risk. We argue that the emphasis of research in this field should be shifted toward explicating the use of risk and benefit perceptions in the process of personal decision-making. Finally, we suggest several social science research approaches that may be used to address these issues.
Telomere Variation in Xenopus laevis

Eukaryotic telomeres are variable at several levels, from the length of the simple sequence telomeric repeat tract in different cell types to the presence or number of telomere-adjacent DNA sequence elements in different strains or individuals. We have investigated the sequence organization of Xenopus laevis telomeres by use of the vertebrate telomeric repeat (TTAGGG)n and blot hybridization analysis. The (TTAGGG)n-hybridizing fragments, which ranged from less than 10 to over 50 kb with frequently cutting enzymes, defined a pattern that was polymorphic between individuals. BAL 31 exonuclease treatment confirmed that these fragments were telomeric. The polymorphic fragments analyzed did not hybridize to 5S RNA sequences, which are telomeric according to in situ hybridization. When telomeric fragments from offspring (whole embryos) were compared to those from the spleens of the parents, the inheritance pattern of some bands was found to be unusual. Furthermore, in one cross, the telomeres of the embryo were shorter than the telomeres of the parents' spleen, and in another, the male's testis telomeres were shorter than those of the male's spleen. Our data are consistent with a model for chromosome behavior that involves a significant amount of DNA rearrangement at telomeres and suggest that length regulation of Xenopus telomeres is different from that observed for Mus spretus and human telomeres.
Ureteral extension in Wilms' tumor: a report from the National Wilms' Tumor Study Group (NWTSG)

Abstract Background Extension of Wilms' tumor into the ureter is a rare event. We reviewed the National Wilms' Tumor Study Group (NWTSG) database to define the clinical presentation, associated pathologic features, and clinical outcome of these patients. Methods Records of children identified to have ureteral extension of Wilms' tumor enrolled in NWTS-3, 4, and 5 were reviewed. Presenting symptoms, diagnostic studies, histopathologic findings, operation performed, and outcome were recorded. The NWTS-5 surgical data were prospectively collected as part of the quality assurance program. Results Forty-five children were identified with ureteral extension. For NWTS-5, the incidence of ureteral extension was 2%. Clinical presentations were gross hematuria in 22 patients, 2 had passage of tissue per urethra, and 1 child had a urethral mass. The remainder had nonspecific presentations. Ureteral extension was seen on preoperative imaging in 14 patients, intraoperatively in 22, and on pathologic examination in 9 patients. Hydronephrosis was noted in 12 patients, and there was nonfunction of the kidney in another 8. Laterality of the tumor was right side in 26 and left in 19. Cystoscopy was performed in 12 children. Findings included tumor seen at the ureteral orifice in 6 patients and bleeding from the orifice in one child. All patients had radical nephrectomy including partial ureterectomy. The ureteral margin was positive in 3 patients, including 2 of the 7 with separate removal of the ureteral extension. The number of patients in each clinical stage was as follows: stage I, 10; stage II, 18; stage III, 14; and stage IV, 3. The tumor extended into the proximal ureter in 23 patients, distal ureter in 13, 7 had extension into the bladder, and 1 had urethral involvement. The level of ureteral extension was not clearly noted in the 45th child. The median follow-up was 96 months. Overall, 41 of 45 patients were alive at last contact. There were 3 deaths because of tumor in patients with unfavorable histologic tumors, and 1 because of treatment toxicity in a child with favorable histologic findings. Conclusions Ureteral extension occurs in approximately 2% of patients with Wilms' tumor. The diagnosis should be suspected in patients with gross hematuria, hydronephrosis, or nonfunctioning kidney. Cystoscopy with retrograde ureterogram may aid in preoperative diagnosis in these patients. Preoperative diagnosis is important because complete resection of the involved portion of ureter at the time of nephrectomy can avoid residual disease and the need for second surgery or radiation therapy.
A Quasi-Symmetric Model for the Two-Way MIMO Communication Channel

It is well-known that the wireless MIMO fading channel at any moment in time and at any frequency is not exactly reciprocal or symmetric. This raises the question of how the forward and reverse channel response matrices are related. Clearly we do not want to forfeit all symmetry and merely consider them as two independent instances of a stochastic fading model. Here a more general relation, called quasi-symmetry, is proposed to relate the incoming and outgoing channel response matrices. We also find that quasi-symmetry is equivalent to simple relations between the complex symmetric singular value decompositions (SVDs) of the two channel matrices. Appropriate background is included on the two kinds of complex linear algebra that originate from the usual conjugate-symmetric scalar product, and the symmetric scalar product, respectively.
Development of a direct current He atmospheric-pressure glow discharge as an ionization source for elemental mass spectrometry via hydride generation

A new direct-current glow discharge has been designed and interfaced with a time-of-flight mass spectrometer. This glow discharge is simple to operate, sustainable in a helium environment at atmospheric pressure at the 40–100 mA level with burning voltages of 0.9–1.2 kV, and capable of generating singly charged atomic ions observable by mass spectrometry. Because of its high first ionization potential (24.6 eV), the presence of He+ in background mass spectra suggests that a significant amount of energy is available for the ionization of gaseous analyte species. In addition, noise power spectra obtained from helium ions in an analyte-free discharge indicate that discrete-frequency noise sources are not present in the atmospheric-pressure glow discharge; only 1/f noise and white noise are found. When this detection system is coupled with hydride generation, the analytical performance of the hydride generation–atmospheric-pressure glow discharge system is comparable with that typically obtained with an inductively coupled plasma ionization source. Although the precision and sensitivity of this system are slightly poorer, the discharge spectrum is free from polyatomic background ions that could otherwise yield problematic isobaric interferences. In addition, a reduction in the overall continuum background enables limits of detection for three routinely-investigated hydride species (arsenic, selenium, and mercury) down to 10 ppt to be realized.
Gender, Race, and the Shadow Structure: A Study of Informal Networks and Inequality in a Work Organization

In this article, I analyze survey data from more than 1,000 financial services employees to understand how gender inequality manifests itself in employees' informal networks. I found that even when Black and white women had jobs in which they controlled organizational resources and had ties to powerful employees, they received less work-related help from their network members than did white men. Drawing on status characteristics theory, I explain that network members were less likely to invest in women than in white men because of cultural beliefs that rank women below that of white men. While past research has documented how employers use gender to rank workers and distribute rewards unequally, my research indicates that workers use gender to categorize and rank their network members as well.
Breastfeeding and delivery room neonatal collapse.

Sudden unexpected neonatal collapse in the delivery room is a rare occurrence in healthy term infants. Upper airway obstruction may occur from improper positioning of the newborn even while breastf...
Alpha Channeling in Mirror Machines

Because of their engineering simplicity, high-β, and steady-state operation, mirror machines and related open-trap machines such as gas dynamic traps, are an attractive concept for achieving controlled nuclear fusion. In these open-trap machines, the confinement occurs by means of magnetic mirroring, without the magnetic field lines closing upon themselves within the region of particle confinement. Unfortunately, these concepts have not achieved to date very spectacular laboratory results, and their reactor prospects are dimmed by the prospect of a low Q-factor, the ratio of fusion power produced to auxiliary power. Nonetheless, because of its engineering promise, over the years numerous improvements have been proposed to enhance the reactor prospects of mirror fusion, such as tandem designs, end-plugging, and electric potential barriers.
Belief Propagation in Large, Highly Connected Graphs for 3D Part-Based Object Recognition

We describe a part-based object-recognition framework, specialized to mining complex 3D objects from detailed 3D images. Objects are modeled as a collection of parts together with a pairwise potential function. An efficient inference algorithm -- based on belief propagation (BP) -- finds the optimal layout of parts, given some input image. We introduce AggBP, a message aggregation scheme for BP, in which groups of messages are approximated as a single message. For objects consisting of N parts, we reduce CPU time and memory requirements from O( N^2 ) to O(N). We apply AggBP on synthetic data as well as a real-world task identifying protein fragments in three-dimensional images. These experiments show that our improvements result in minimal loss in accuracy in significantly less time.
THE EFFECTS OF CONDUCTING BEHAVIORAL OBSERVATIONS ON THE BEHAVIOR OF THE OBSERVER

Behavior-analytic approaches to occupational safety are often effective for improving safety in organizations, and have been successful in a wide variety of settings. The effects of these safety processes are thought to arise primarily from the behavioral observation process and the delivery of feedback. Typically, supervisors or employee observers involved in behavioral safety implementations conduct observations. The present study was an attempt to assess the effects of conducting observations on an observer's safety performance. An ABC multiple baseline counterbalanced across two sets of behaviors was conducted in a simulated office. The target behaviors involved knee and back positions during lifts; back, shoulder, and feet positions while sitting; neck and wrist positions while typing; and neck position during phone use. Substantial improvements in safety performance occurred after participants conducted observations on a videotape of a confederate's performance. The possible behavioral functions responsible for this change, and the implications of these findings for applied settings, are discussed.
Balanced reciprocal X-4 translocation in a female patient with early secondary amenorrhea

Balanced translocations involving an X chromosome and an autosome have been infrequently reported. A patient with a balanced X-autosome translocation 46,X,rcp(X;4)(q26;q21) who exhibited early secondary amenorrhea and gonadal dysgenesis is described. In an effort to explain the varied phenotypic expressions encountered in female cases of balanced X-autosome translocations, evidence will be provided to suggest an extension of the minimal limits of the "critical region" in the long arm of the X chromosome from A-B, as described by Sarto and associates, to new minimal limits C-D.