cssi/SciSciGPT-SciSciNet huggingface dataset:
Remote sensing of atmospheric turbulence and transverse atmospheric winds using optical reference sources

In the theory of atmospheric turbulence, the strength of the spatial variations of the index of refraction n is proportional to a parameter known as the atmospheric structure constant, denoted Cn2, which is a function of position along the optical path z. The strength of the temporal variations of the index of refraction is directly related to the transverse velocity YLDV of the turbulence along z. Current optical techniques for remotely sensing Cn2 and YLDV rely primarily upon the spatial or temporal cross-correlation properties of the intensity of the optical field. In the technique proposed here, we exploit the correlation properties of the wave front slope measured from two different point sources in order to obtain vertical profiles of Cn2(z) and YLDV(z). Resolution on the order of 100 meters is possible with reference sources separated by 0.2 degrees. Additionally, signal-to-noise ratio (SNR) calculations for a single measurement of Cn2 and YLDV are presented for a Hufnagel-Valley Cn2 profile and a Bufton wind profile. The SNR results indicate the need for multiple measurements to obtain useful estimates of the desired quantities.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Factored Multiplicative Mismatched Filters for Compound Barker Codes

In this paper, factored multiplicative mismatched filters for compound Barker codes are presented. It is based on factored representations of compound codes in the z-domain. The mismatched filter for the compound code is expressed as a cascade of the mismatched filters of the component codes. Multiplicative mismatched filters, recently introduced by the authors, are used as the filters for the component codes. The proposed filters are not optimal for the given filter length, but, due to their structured implementation, use fewer additions and multiplications per output than the length-optimal filters to achieve a given mainlobe to sidelobe ratio (MSR). Results are shown for various compound Barker codes.
Ammonium Dinitramide: Kinetics and Mechanism of Thermal Decomposition

Thermal decomposition of ammonium dinitramide (ADN) has been studied by differential scanning calorimetry (DSC) and thermal gravimetry combined with mass spectrometry (TG−MS). ADN decomposes in the range 130−230 °C with an overall heat release of 240 ± 40 kJ mol-1. The product gases have been identified by MS as NH3, H2O, NO, N2O, NO2, HONO, and HNO3. The global activation energy determined from TG experiments decreases from 175 ± 20 kJ mol-1 at the beginning of the reaction to 125 ± 20 kJ mol-1 when the reaction is near completion. Experiments conducted at different carrier gas flow rates indicate that the reaction is catalyzed by product gases released during the reaction. A condensed phase ionic reaction mechanism is proposed, in which ammonium nitrate and ammonium mononitramide (NH4NNO2) are formed as intermediates in two competing channels.
From Family Planning To HIV/AIDS Prevention To Poverty Alleviation: A Conversation With Mechai Viravaidya

ABSTRACT: In this interview, Mechai Viravaidya shares how he harnessed the media and various other distribution channels in Thailand to launch nationwide programs aimed at changing attitudes, belie...
Validity of record ratings of the Global Assessment Scale

The Global Assessment Scale (GAS) is a comprehensive rating of psychiatric status that is usually based on face-to-face interviews. Validity has not been established for the use of the GAS when it is based on secondary sources of information about the patient, source of patient information, although secondary sources have been used for this purpose. The current study examined agreement between GAS ratings based on medical records and ratings based on face-to-face interviews. Results showed moderate agreement between the two sets of ratings, with the intraclass correlation-coefficient (ICC) equaling .62. Record-based (R)-GAS ratings were upwardly biased and were restricted in range when compared with interview-based (I)-GAS ratings. A case-by-case analysis showed that the disagreement could be accounted for by inconsistent documentation of the degree of functional impairment in the most severely disturbed patients. We conclude the following: If R-GAS ratings are used, designs should be modified to adjust for probable overestimated functioning of the most severely disturbed patients.
Feed-quality variation in the barley core Collection of the USDA National Small Grains Collection

Feed is an important end use of barley (Hordeum vulgare L.). Recent research has identified high starch content, low acid-detergent fiber (ADF), low ruminal dry-matter digestibility (DMD), and large particle size after dry rolling as desirable barley feed-quality characteristics for beef cattle. Knowledge about the variation available may help barley breeders develop strategies for feed-quality improvement. Our objective was to estimate the variation in feed-quality characteristics in barley around the world. The spring barley core subcollection from the USDA-ARS National Small Grains Collection was planted in 1995. Ruminal DMD of 1480 accessions was evaluated. Seventy-three accessions, selected on variation in DMD, were planted in two field replications in 1996 and 1997. These 73 accessions were evaluated for starch, DMD, ADF, and particle size after dry rolling. The range in DMD was 82 to 621 g kg -1 , with a mean of 398 g kg -1 (SD = 75 g kg -1 ). The ranges for other traits of the 73 selected accessions were 387 to 593 g kg -1 (starch); 15 to 96 g kg -1 (ADF); 187 to 510 g kg -1 (DMD); and 1118 to 1572 μm (particle size). Six-row types had greater ADF and particle size (P < 0.001), lower starch, and DMD (P < 0.001), compared with 2-row types. Starch was higher (P < 0.01), and ADF and DMD were lower (P < 0.01), for hulless than for hulled accessions. Substantial variation in the spring barley core collection for feed quality-related characters could be exploited to develop barley cultivars for feed quality.
Medical image diagnoses by artificial neural networks with image correlation, wavelet transform, simulated annealing

Classical artificial neural networks (ANN) and neurocomputing are reviewed for implementing a real time medical image diagnosis. An algorithm known as the self-reference matched filter that emulates the spatio-temporal integration ability of the human visual system might be utilized for multi-frame processing of medical imaging data. A Cauchy machine, implementing a fast simulated annealing schedule, can determine the degree of abnormality by the degree of orthogonality between the patient imagery and the class of features of healthy persons. An automatic inspection process based on multiple modality image sequences is simulated by incorporating the following new developments: (1) 1-D space-filling Peano curves to preserve the 2-D neighborhood pixels' relationship; (2) fast simulated Cauchy annealing for the global optimization of self-feature extraction; and (3) a mini-max energy function for the intra-inter cluster-segregation respectively useful for top-down ANN designs.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
The role of polyols in cerebral cell volume regulation in hypernatremic and hyponatremic states.

Abstract To clarify the role of the sugar polyols, sorbitol and myo-inositol, in cerebral cell volume regulation, we studied the effect of sorbinil, an inhibitor of aldose and aldehyde reductase, on the size of the cerebral water compartments in rats with hypernatremia, hyponatremia and normonatremia. Experimental animals were pretreated with sorbinil, while comparison rats received the drug vehicle. Rats were made hypernatremic for 96 h by water deprivation and injections of hypertonic saline, while hyponatremia was provoked over 48 h by daily administration of 5% dextrose in water and vasopressin. Sorbinil treatment was continued throughout the hyper- and hyponatremic periods. The severity of hypernatremia and hyponatremia was similar in sorbinil-treated and corresponding vehicle-treated rats. Brain electrolyte content and the size of the cerebral intracellular water compartment were comparable in sorbinil-treated rats vs . controls under hypernatremic and hyponatremic conditions. Sorbinil reduced the cerebral sorbitol content by approximately 50%, irrespective of the serum Na + concentration. In contrast, sorbinil had no effect on brain myo-inositol content which rose by 114% during chronic hypernatremia (P
Market Power and Incentives to Form Research Consortia

It is well known that instability is a limit to the formation of cartels, and that some synergies are required to give cartel members an advantage over outsiders. In this paper, we explore theoretically the linkage between cost-reduction alliances (like research joint ventures) and the formation of cartels. The former have negative external impacts on outsiders, while the latter have positive external effects on outside (independent) competitors. We find that when the decisions to join both are made simultaneously the cartel can be profitable and stable for a smaller number of members than previously found for cartel formation alone by Salant et al. (1983, Quarterly Journal of Economics 98, 185–199). This result follows both for open membership and exclusive membership rules, and suggests a possible anticompetitive impact of research joint ventures.
Detection of estrus in cattle housed in stanchions by constant human observation of behavioral traits

Abstract Five heifers and five lactating dairy cows were locked in adjacent stanchions and monitored continuously by human observation for 18 consecutive nights from 7:00 p.m. to 4:00 a.m. Total standing and lying time, number of position changes, and prevalence of bellowing was recorded. The animals were housed in stanchions for 20 hours each day and in outside lots for four hours each day. Estrus was synchronized by giving prostaglandins on Days 1 and 11. There were 16 documented estrous periods, and an increase (P These results indicate that standing time, number of position changes, and bellowing are rather weak indicators of estrus.
Annual operation expense for residential water heaters with and without a pollution penalty factor

Two models are used for assessing the annual operation costs of electric and natural-gas residential water heaters. One model estimates the real utility costs based on local utility rates, water-heater efficiency, daily water usage, and average required temperature rise. The other adds (to this) penalizing factors for the amount of carbon dioxide and sulphur dioxide produced by either electricity generation by a coal-fired power plant or the carbon dioxide released when burning natural gas with stochiometric air. An analysis is done of low-, medium- and high-efficiency models of electric, natural-gas and heat-pump-style water heaters.
Path planning for altruistically negotiating processes

Autonomous negotiating systems are composed of logically (even geographically) separated software agents that control logical or physical resources that altruistically seek to perform useful work in a cooperative manner. These systems are multi-agent systems that consist of a population of autonomous agents collaborating to work for a common goal while simultaneously performing their individual tasks (i.e., computational resources are distributed amongst interconnected agents). With the increasing capabilities of the collaborative agents, the need for faster and more efficient methods of utilizing the distributed resources has also increased. This paper focuses on improving the performance of one such multi-agent system that deals with the path planning for autonomous robots. This is achieved by exploiting parallelism among processing resources embedded in the autonomous vehicles, using a distributed memory, message-passing execution model
Analyses and preliminary tests of a balsa sandwich core with improved shear properties

End grain balsa is a common core material in sandwich structures. The main properties of interest of a sandwich core, in particular for marine applications, are the shear stiffness and shear strength. The end grain arrangement does not fully utilize the anisotropy of balsa wood for the benefit of shear properties. A new arrangement of balsa blocks in a sandwich core was developed and numerically analyzed. This new core, which consisted of an assembly of oddly shaped balsa blocks, allowed the grains in various balsa blocks to be oriented for example at 45° to the normal of the core. The effective out-of-plane shear stiffness was isotropic. Numerical analyses predicted a superior shear stiffness, which was confirmed by preliminary tests.
Interpreting Rural Industrial Growth in the Post-Mao Period:

Decollectivization of agriculture in the post-Mao period set off a chain of dizzying changes in the rural economy. Along with the transfer of agricultural production decisions to rural households, a host of restrictions were lifted on nonagricultural activities. With peasants freed to leave agriculture, many turned to handicrafts, peddling, transport, and other service trades. This outflow turned into a stampede when rural private enterprises were officially sanctioned in 1984. By the end of the year, some 100 million rural peasants were working in nonfarm activities, many in rural enterprises (Beijing Review, February 4, 1985: 4). These changes led to a phenomenal burst of activity in the rural enterprise sector. In 1984 alone, the number of enterprises more than quadrupled, jumping to 6.07 million, up from 1.35 million in 1983; in the following year, another 6.2 million enterprises were added. Employment in these enterprises rose from 32.4 million in 1983 to 52.1 million in 1984 and 69.8 million in 1985. Their gross value of output increased by 68% and 60% in the two years, respectively. In 1985, these enterprises produced goods and services worth 273 billion yuan, nearly three times their output value in 1983 (see Table 1). By 1986, the gross value of output
Museums and parent involvement: a landscape review

The aim of this study was to gather descriptive data about the nature of museum-designed and -implemented parent-involvement programs across the United States, investigating two research questions: (1) How many and what types of museums offer programs that target parents in support of their children's education? and (2) What do these programs look like? What are their goals and what is the nature of their activities? Questionnaires were used to investigate the above-mentioned research questions. We sampled American museums that are accredited by the American Alliance of Museums. Our data suggest that a sizeable number of museums are engaged in parent-involvement efforts, and we argue that these data form an important foundation for future museum programming.
Modeling and optimization of wireless local area network

As wireless local area network technology is gaining popularity, performance analysis and optimization of it becomes more important. However, as compared to wired LAN, wireless channel is error-prone. Most of the existing work on the performance analysis of IEEE 802.11 distributed coordination function (DCF) assumes saturated traffic and ideal channel condition. In this paper, modeling of DCF is analyzed under a general traffic load and variable channel condition. A more realistic and comprehensive model is proposed to optimize the performance of DCF in both ideal and error-prone channels, and for both the basic scheme of DCF and DCF with four-way handshaking. Many factors, such as the number of contending nodes, the traffic load, contention window, packet overhead and channel condition, that affect the throughput and the delay of a wireless network have been incorporated. It is shown that under error-prone environment, a trade-off exists between the desire to reduce the ratio of overhead in the data packet by adopting a larger packet size, and the need to reduce the packet error rate by using a smaller packet length. Based on our analytical model, both the optimal packet size and the optimal minimum contention window are determined under various traffic loads and channel conditions. It is also observed that, in error-prone environments, optimal packet size has more significant improvement on the performance than optimal contention window. Our analytical model is validated via simulations using ns-2.
Interactions of thiophenes with C300 Basolite MOF in solution by the temperature-programmed adsorption and desorption, spectroscopy and simulations

Aromatic sulfur compounds, e.g. thiophene (T), benzothiophene (BT), dibenzothiophene (DBT), 4,6-dimethyldibenzothiophene (4,6-DMDBT) are present in petroleum and fossil fuels, and cause air pollution, degradation of catalytic converters, deactivation of fuel-reforming catalysts. In this paper, we report kinetic, thermodynamic, spectroscopic and computational studies of adsorption of T, BT, DBT, and 4,6-DMDBT from solution in n-alkane on metal–organic framework (MOF) Basolite C300 at 25–115 °C. The novel temperature-programmed adsorption/desorption method allows the in situ measurement of an adsorption capacity at the variable temperature, and after the cycle “adsorption/desorption”. Adsorption of BT, DBT and 4,6-DMDBT at 25 °C occurs via the formation of the stoichiometric 1:1 adsorption complexes. BT adsorbs reversibly, while 4,6-DMDBT adsorbs irreversibly. The formation of the adsorption complex of the aromatic sulfur compound with MOF is confirmed by the fluorescence spectroscopy for the first time. The DFT computations of the geometry and energy of dispersive versus electronic interactions of T and DBT with the structural units of the C300 MOF are reported for the first time. The mechanism of adsorption is proposed as a combination of dispersive and electronic interactions of the aromatic sulfur compounds with BTC linker and Cu(II) CUS of C300 MOF.
The horse and high altitude

Abstract A number of physiological processes become altered at increased altitude. While much has been published regarding the physiological adaptations to high altitude in humans, relatively few reports detail the responses of horses to similar environments. As horses are utilized not only to carry loads in mountainous terrain, but also for various athletic and recreational endeavors at high altitude, an understanding of the normal physiological responses in this species is of some importance. This review serves to detail what is presently known about the normal adaptive responses of horses to activity at high altitude, and to highlight some of the more common abnormal responses that might be used to indicate physiologic dysfunction.
An analysis of oblique angle stimulated Cherenkov radiation with some experimental results

This paper considers the possible amplification in a dielectric medium of a plane wave intersected by an electron beam at the Cherenkov angle. An oscillator is designed in which a Fabry-Perot resonator's axis is placed at this angle. The gain is found to be inversely proportional to the wavelength, suggesting the possibility of a vacuum ultraviolet or soft X-ray laser. The randomization of the phase coherence between the wave and the electrons due to multiple scattering of the electrons by the atoms of the dielectric is minimized by limiting the length of interaction, and increasing the electron beam energy. Early unpublished experiments are given in which quartz resonators were placed in the Mark III Linear Accelerator's electron beam at Stanford University. From this, other subsequent experimental work, and the theory derived here. two devices are considered which utilize gas as a dielectric instead of a solid.
Research notes and reports

This Department publishes research notes, conference reports, reports on the work of public agencies and associations, field (industry) reports, and other relevant topics and timely issues. Individuals interested in submitting notes and reports should write directly to the Associate Editor for Research Notes and Reportscf, Turgut Var (Department of Recreation, Park and Tourism Sciences, Texas A&M University, College Station TX 77843-2261, USA).
Decomposition of Benzhydrol catalysed by Boric Acid

IN a recent investigation of the secondary decomposition mechanisms in the pyrolysis of esters, it was discovered that the borate of benzyl alcohol decomposes to anthracene and resinous substances1. This result supports the contention of Chapman and Borden2 that the elimination involves an ionic mechanism.
Preclinical Evaluation of GBR12909 Decanoate as a Long-Acting Medication for Methamphetamine Dependence

Methamphetamine (METH) abuse is a growing health problem, and no treatments for METH dependence have been identified. The powerful addictive properties of METH are mediated by release of dopamine (DA) from nerve terminals in mesolimbic reward pathways. METH stimulates DA release by acting as a substrate for DA transporter (DAT) proteins, thereby triggering efflux of DA from cells into the synapse. We have shown that blocking DAT activity with high-affinity DA uptake inhibitors, like GBR12909, can substantially reduce METH-evoked DA release in vitro, suggesting GBR12909 may have potential as a pharmacotherapy for METH dependence. The purpose of the present study was to examine the neurobiological effects of a long-acting oil-soluble preparation of GBR12909 (1-[2-[bis(4-fluorophenyl)methoxy]ethyl]-4-(3-hydroxy-3-phenylpropyl) piperazinyl decanoate, or GBR-decanoate). Male rats received GBR-decanoate (480 mg/kg, i.m.) or its oil vehicle, and were tested using a variety of methods one and two weeks later. Ex vivo autoradiography showed that GBR-decanoate decreases DAT binding in DA-rich brain regions. In vivo microdialysis in the nucleus accumbens revealed that GBR-decanoate elevates baseline levels of extracellular DA and antagonizes the ability of METH to evoke DA release. The dopaminergic effects of GBR-decanoate were sustained, lasting for at least two weeks. Rats pretreated with GBR-decanoate displayed enhanced locomotor responses to novelty at one week, but not two weeks, postinjection. Administration of the D(2)/D(3) receptor agonist quinpirole (10 and 100 microg/kg, s.c.) decreased locomotor activity and suppressed plasma prolactin levels; quinpirole-induced responses were not altered by GBR-decanoate. Thus, GBR-decanoate is able to elevate basal synaptic DA levels and block METH-evoked DA release in a persistent manner, without significant perturbation of DA receptor function. The findings suggest that GBR-decanoate, or similar long-acting agents, should be evaluated further as potential treatment adjuncts in the management of METH addiction in humans.
Transmission of Pantoea ananatis, Causal Agent of Center Rot of Onion, by Tobacco Thrips, Frankliniella fusca

Center rot of onion, caused by Pantoea ananatis, was first reported on onion in Georgia in 1997 and has continued to reduce yields and cause postharvest losses. In a previous study, we developed a nondestructive assay that demonstrated an association between P. ananatis and approximately 10% of the tobacco thrips, Frankliniella fusca, surveyed. In this study, we report that all strains of P. ananatis, isolated from surface-sterilized, crushed thrips, were pathogenic when inoculated onto greenhouse-grown onion plants. Furthermore, when 6 to 12 thrips harboring populations of P. ananatis of 1 × 103 CFU ml-1 or greater were placed on healthy onion seedlings to feed, disease transmission occurred in 52% of the plants challenged. Incubation periods ranged from 4 to 9 days. Bacteria isolated from symptoms typical of those associated with center rot were characterized and identified as P. ananatis. In contrast, an equal number of plants remained healthy for up to 28 days after being exposed to the same number of tobacco thrips that were identified as being free of P. ananatis.
Pass the Biscuits, Pappy: Congressional Decision-Making and Federal Grants

This article examines the congressional allocation of federal grant funds. Reflecting the decision processes and norms of Congress, federal grant funds are allocated almost completely on the basis of population (or equal share). None of the other factors used to allocate specific federal funds (e.g., income, poverty, unemployment) have a great deal of impact. As a result, most congressional battles are at the margin with only marginal impact on the overall distribution.
TOPEX: Observing the oceans from space

Measurement of global ocean topography by a radar altimeter aboard the TOPEX satellite is discussed. Technical aspects of satellite altimetry as they pertain to the measurement of ocean circulation are described. The TOPEX mission is explained and a general history of oceanography is included.
Content-Based Language Teaching with Functional Grammar in the Elementary School.

Today many second language (L2) teachers work with school-aged learners who need to be supported in their language development at the same time they learn school subjects. Applied linguists and researchers in second language acquisition (SLA) have much to contribute to those teachers, but to do so in more powerful ways calls for an orientation toward the goals of the content classroom. This plenary describes a project in which the theory of systemic functional linguistics is providing useful metalanguage for exploring language and meaning in curricular activities that also support disciplinary learning. It illustrates how language-based content teaching can provide the support children need.
BOOKS IN ENGLISH FOR THE STUDY OF GERMAN

Author's summary.— A selective and critical bibliography of recent books in English on Germany.
Process Philosophy and the Question of Life's Meaning

Recent discussions, principally among analytic philosophers, concerning the meaning and the validity of the ‘question of life's meaning’ (hereafter referred to as QLM) are significant in several ways. They indicate how analytic philosophy, long charged with sterility, can clarify deeply human questions. They suggest useful avenues of discussion between the analysts and the existentialists, phenomenologists and process philosophers. And they offer some illuminating discriminations between theism and naturalism, and between religious and non-religious understandings of life. But an additional consequence of these discussions is the emergence of a series of challenges to most forms of theism, especially Christianity. In this paper we will be concerned with the latter.
High-k Dielectrics and Dual Metal Gates: Integration Issues for New CMOS Materials

Several metal and conducting metal nitride candidates were investigated for alternative gate electrode applications in future complimentary metal-oxide-semiconductor (CMOS) devices. High frequency capacitance-voltage (CV) measurements were performed on n-MOS and p-MOS capacitors with Al, Ta, TaN, TIN, or W 2 N gates and ultra-thin SiO 2 /Si 3 N 4 dielectric stacks. The work functions of Al and Ta were close to the conduction band of Si as expected while all the metal nitrides had work functions slightly above mid-gap. The thermal stability of the metal nitrides and the metal/dielectric interfaces was studied by Auger electron spectroscopy (AES) following rapid thermal annealing (RTA). Integration requirements for dual metal gate electrodes in future CMOS devices are discussed.
"No Balance In The Equities": Union Power In The Making And Unmaking Of The Campaign Finance Regime

Broad developments in the political economy, coupled with the effects of the Federal Election Campaign Act of 1971 (FECA) and its amendments, have weakened organized labor's position in campaign politics. The number of business-related political action committees (PACs) exploded at the end of 1975, and quickly dwarfed the number of labor PACs. More significant are trends in spending. In 1977–1978 business-related PACs outcontributed labor committees by approximately $100 million in 1995–1996.Larry Makinson, Open Secrets: The Dollar Power of PACs in Congress (Washington, DC: Congressional Quarterly, 1990), 19; Larry Makinson, Open Secrets: The Encyclopedia of Congressional Money and Politics, 2d ed. (Washington, DC: Congressional Quarterly, 1992), 21; Makinson and Goldstein, Open Secrets, 3d ed., 21; Center for Responsive Politics, “Business-Labor-Ideology Split in Donations from PACs,” http://www.crp.org/pubs/bigpicture/blio/bpbliopac.html. There is some dispute about the full magnitude of the differences between business and labor PAC contributions, but it is clear that there is a large and growing gap between direct contributions to candidates from business and from labor.
Stability of the Latent Reservoir for HIV-1 in Patients Receiving Valproic Acid

In light of a recent report that short-term treatment with valproic acid (VA) might accelerate the decay of the latent reservoir for HIV-1 in patients receiving combination therapy and allow eventual eradication of the infection, we studied patients with prolonged suppression of viremia who were receiving combination therapy and who had also been receiving chronic VA therapy for neurological or psychiatric conditions. Latently infected cells were readily detected in all patients at levels comparable to those seen in patients receiving combination therapy alone. We conclude that the clinical use of VA has no ancillary effect on the decay of the latent reservoir.
Assessment by reflection ultrasound method of the effect of intermittent slow‐release sodium fluoride‐calcium citrate therapy on material strength of bone

It has been suggested that fluoride therapy, while increasing bone mass, produces bone with inferior mechanical properties. In the present report this hypothesis was tested using a novel reflection ultrasound technique. Transiliac crest bone biopsies were obtained from 16 patients with osteoporosis and vertebral compression fractures (12 women and 4 men, mean age 56 years) before and after approximately 2 years of intermittent slow-release sodium fluoride therapy (25 mg twice a day) combined with continuous calcium citrate supplementation. Samples were analyzed by a reflection ultrasound method, which analyzes ultrasound velocity with a sample site resolution of 200 microns and thus provides a measure of the mechanical property of single trabeculae (material). For the group, mean fractional change in velocity increased 6.1 +/- 2.3% (SEM) from a mean value of 3303 +/- 80 to 3484 +/- 55 m/s (p = 0.028). A total of 13 patients (81%) demonstrated higher velocities after treatment. Thus reflection ultrasound analysis of bone appears to provide a sensitive means of assessing changes in the material property of bone. Furthermore, these results suggest that the treatment regimen utilized in these patients improves strength of bone at the material or trabecular level largely independently of change in bone mass. The combination therapy also increased spinal (L2-L4) bone density for the group as assessed by dual-photon absorptiometry (5.3 +/- 2.0%). There was no significant correlation between the change in ultrasound velocity and bone density (r = 0.0026, p = 0.996).(ABSTRACT TRUNCATED AT 250 WORDS)
Segmental migration of trunk neural crest: time-lapse analysis reveals a role for PNA-binding molecules

Trunk neural crest cells migrate through the somites in a striking segmental fashion, entering the rostral but not caudal sclerotome, via cues intrinsic to the somites. Attempts to define the molecular bases of these cues have been hampered by the lack of an accessible assay system. To examine trunk neural crest migration over time and to perturb candidate guiding molecules, we have developed a novel explant preparation. Here, we demonstrate that trunk regions of the chicken embryo, placed in explant culture, continue to develop apparently normally for 2 days. Neural crest cells, recognized by prelabeling with DiI or by poststaining with the HNK-1 antibody, migrate in the somites of the explants in their typical segmental pattern. Furthermore, this paradigm allows us to follow trunk neural crest migration in situ for the first time using low-light-level videomicroscopy. The trajectories of individual neural crest cells were often complex, with cells migrating in an episodic mode encompassing forward, backward and lateral movements. Frequently, neural crest cells migrated in close-knit groups of 2–4 cells, moving at mean rates of migration of 10–14 µm/hour. Treatment of the explants with the lectin peanut agglutinin (PNA) both slowed the rate and altered the pattern of neural crest migration. Neural crest cells entered both the rostral and caudal halves of the sclerotome with mean rates of migration ranging from 6 to 13 µm/hour. These results suggest that peanut agglutinin-binding molecules are required for the segmental patterning of trunk neural crest migration. Because this approach permits neural crest migration to be both observed and perturbed, it offers the promise of more direct assays of the factors that influence neural crest development.
Children’s gestures are meant to be seen

This study investigated whether children alter their gestures when their listeners cannot see those gestures. Sixteen kindergarten children viewed four short cartoon episodes. After each episode, the child retold the story to an adult listener. For two episodes, the child and listener sat face-to-face, and for the other two episodes, an opaque curtain was placed between them. Children gestured at a significantly higher rate when they could see their listeners than when they could not. However, the amount, fluency, and content of children’s speech did not differ across conditions. Thus, kindergarten children alter their gestures to suit their listeners, and the observed changes in gesture do not appear to depend on changes in speech.
HIV genes diversify in B cells.

Mutation of the human immunodeficiency virus by host cells inhibits viral dissemination by creating nonfunctional variants. However, viral mutation does not always eliminate the ability of the virus to disseminate and, in fact, is thought to promote persistence by generating functional mutants that evade immunity or drugs. How and where HIV mutates is not known. Accordingly, where and to what extent variants emerge may be determined by the cell type with optimal mutation apparatus as well as by the properties of the viral genomic sequence itself. Here we considered that HIV, which can infect B cells, may co-opt the Ig somatic hypermutation machinery to generate functional variants and asked whether the HIV envelope coding sequence can diversify in B cells. We show that an HIV envelope coding sequence transfected into B cells mutates in a manner consistent with somatic hypermutation, causing the production of viral protein variants. This result demonstrates that B cells can express and diversify HIV proteins. Thus, B cells may contribute to viral evasion and to the development of multi-drug resistance.
Health services use in women with a history of bulimia nervosa or binge eating disorder.

Objective: The current study examined health services use during the past 12 months in a sample of young women with a history of an adolescent eating disorder (bulimia nervosa [BN] or binge eating disorder [BED]). Method: A community sample of 1,582 young women (mean age = 21.5 years) was classified, based on a screening interview (and, for eating disorder diagnosis, confirmatory diagnostic interview), into one of three groups: BIN or BED (n = 67), other psychiatric disorder (n = 443), and no adolescent psychiatric disorder (n = 1,072). Results: A history of BN/BED in adolescence was associated with elevated health services use, but this was a general effect associated with having a psychiatric disorder, not an effect specific to the diag- nosis of an eating disorder. Total service days, outpatient psychotherapy visits, and emergency department visits were elevated in the combined group of BN/BED and other psychiatric disorder participants relative to the healthy comparison group. The women with BN/BED did not differ significantly from the women with a non-eating-related psychiatric disorder in the use of these services. Discussion: The similarity of health services use in young women with BN or BED and those with other psychiatric disorders underscores the clinical and economic impact of these eating disorders. (C) 2004 by Wiley Periodicals, Inc.
Turbulence and Scalar Gradient Dynamics in Premixed Reacting Flows

The interaction between turbulence and premixed flames is examined for a range of turbulence intensities using results from direct numerical simulations of premixed stoichiometric hydrogen-air combustion. Particular focus is placed on the interaction of the turbulent vorticity and strain rate fields with the scalar gradient in the presence of very intense turbulence, where the scalar is the reactant mass fraction. Analysis of the scalargradient magnitude shows that, for all turbulence intensities, the flame is broadened in the preheat zone, but remains close to the laminar flame width in the reaction zone. In agreement with previous studies, broadening of the reaction zone is not observed for even the largest intensities. Consideration of the terms in the scalar gradient transport equation shows that the strain rate acts to reduce the scalar-gradient magnitude for small turbulence intensities, while it increases the magnitude for large intensities. The vorticity and strain rate magnitudes are suppressed in the reaction zone of the flame, but this suppression decreases in strength as the turbulence intensity increases. The interactions between the vorticity, strain rate, and scalar gradient are substantially influenced by heat release for small turbulence intensities. For intense turbulence, however, these interactions are similar to those observed in nonreacting turbulence. This paper uses data from a series of direct numerical simulations to examine the interactions of flames and turbulence in premixed, stoichiometric hydrogen and air combustion. 1 Particular focus is placed on the properties of the gradient of the reactant mass fraction, Y , where this scalar gradient reflects properties of the flame. The present simulations are extensions of those described in Ref. [1], and are carried out for a range of turbulence intensities, from IT ≡ Urms/SL =2 .45 to 30.6, where Urms is the rms turbulent velocity in the unburned mixture and SL is the laminar flame speed. Previous studies of the scalar gradient in premixed flames 2–6 have typically considered lower turbulence intensities; for example, Chakraborty and Swaminathan 3 examined premixed flames where IT =1 . 4a nd 7.6, and Kim and Pitsch 4 examined IT =1 3.8 and 19.5. For the range of turbulence intensities examined here, substantial differences in the interaction between the flame and turbulence are expected, resulting in changes to the properties of both the turbulence and the scalar gradient. These changes, and their connection to variations in the turbulence intensity, are the focus of the present study. In order to examine the interaction between the flames and turbulence, here we consider the coupled dynamics of the turbulent vorticity and strain rate with the dynamics of the scalar gradient. The vorticity, ω(x,t), is defined in terms of the velocity, ui(x,t), as
Activity of purified QscR, a Pseudomonas aeruginosa orphan quorum-sensing transcription factor.

Summary The opportunistic pathogen Pseudomonas aeruginosa has two acyl-homoserine lactone (acyl-HSL) signalling systems, LasR-I and RhlR-I. LasI catalyses the synthesis of N-3-oxododecanoyl homoserine lactone (3OC12) and LasR is a transcription factor that requires 3OC12 as a ligand. RhlI catalyses the synthesis of N-butanoyl homoserine lactone (C4) and RhlR is a transcription factor that responds to C4. LasR and RhlR control the transcription of hundreds of P. aeruginosa genes. There is a third P. aeruginosa LasR-RhlR homologue encoded by qscR for which there is no cognate acyl-HSL synthase gene. To test the hypothesis that QscR functions by direct control of specific promoters in an acyl-HSL-dependent manner we purified QscR and characterized QscR activity in vitro. We also studied QscR activity in recombinant Escherichia coli. QscR binds to promoters that have elements similar in sequence to those found in LasR- or RhlR-dependent promoters but QscR does not bind to the LasR- or RhlR-specific promoters we examined. QscR binding to DNA requires 3OC12, but QscR exhibits a relaxed acyl-HSL specificity compared with the 3OC12-cognate signal receptor LasR. Our results support the hypothesis that there is a specific QscR-dependent regulon. We show that QscR controls genes in this regulon directly and that regulation is dependent on an acyl-HSL produced by LasI. Because of its relaxed signal specificity QscR may also respond to acyl-HSLs made by other bacteria in mixed bacterial communities.
Hypertonic NaCl inhibits gastric motility and food intake in rats with lesions in the rostral AV3V region

Several diverse treatments that stimulate pituitary secretion of oxytocin (OT) in rats produce a parallel inhibition of gastric motility and food intake. The present experiments demonstrate that injection of hypertonic saline (HS) is another such treatment. Systemic administration of large doses of OT had no effect on gastric motility. Lesions within the region anteroventral to the third ventricle (AV3V region) severely impaired the drinking response to HS without affecting its inhibition of either gastric motility or food intake. These and other results suggest that despite the close association of pituitary secretion of OT with inhibition of both gastric motility and food intake in intact animals after HS administration, these effects may be dissociated by lesions within the AV3V region. Consequently, osmosensitive cells located within the periventricular tissue of the rostral AV3V region, which are critical for the stimulation of thirst and pituitary OT secretion after systemic injection of HS, do not appear to be essential for the parallel inhibition of gastric motility and food intake produced by this treatment in rats.
Low-dimensional hyperthin FeS2 nanostructures for efficient and stable hydrogen evolution electrocatalysis

We report a scalable, solution-processing method for synthesizing low-dimensional hyperthin FeS2 nanostructures, and we show that 2D FeS2 disc nanostructures are an efficient and stable hydrogen evolution electrocatalyst. By changing the Fe:S ratio in the precursor solution, we were able to preferentially synthesize either 1D wire or 2D disc nanostructures. The 2D FeS2 disc structure has the highest electrocatalytic activity for the hydrogen evolution reaction, comparable to platinum in neutral pH conditions. The ability of the FeS2 nanostructures to generate hydrogen was confirmed by scanning electrochemical microscopy, and the 2D disc nanostructures were able to generate hydrogen for over 125 h.
Stock Market Jumps and Uncertainty Shocks During the Great Depression

Stock market volatility was extremely high during the Great Depression relative to any other period in American history. At the same time, large negative and positive discontinuous jumps in stock returns can be detected using the Barndorff-Nielsen and Shephard (2004) test for jumps in financial time-series. These jumps coincided with periods when stock volatility was high as the arrival of new information about the uncertain future drove both the record stock volatility and the record jumps in stock returns. A timeline of the Depression is outlined, with important events that drove uncertainty highlighted such as the collapse of the banking system, policy changes, the breakdown of the gold standard, monetary policy uncertainty, and war jitters.
Racialized Assumptions and Constitutional Harm: Claims of Injury Based on Public School Assignment

In a disciplinary transfer claim, a student alleges a violation of procedural due process based on an involuntary assignment to an alternative school for disciplinary purposes. Courts hearing disciplinary transfer claims have struggled with whether to recognize or accord significant weight to the injury caused by assignment to a particular public school. In contrast, the Supreme Court recently accepted that injury without discussion in the context of an equal protection challenge to a school desegregation plan. This article argues that the different approaches result not from differences in the doctrines underlying the two types of claims, but from differences in the racial composition of the presumptive plaintiff class. The assumption that white students have educational options not available to students of color causes courts to apply a different model of educational entitlement in each type of claim. The article concludes that courts must apply the same model in all education claims in order to avoid perpetuating racial subordination.
Factor V activity of platelets: evidence for an activated factor V molecule and for a platelet activator

This study was prompted by the observation that fresh platelet suspensions--prepared by gel filtration or albumin density gradient centrifugation--possessed only minimal factor V activity, whereas frozen-and-thawed platelet suspensions possessed striking factor V activity. Results of experiments with fresh suspensions suggested that unaltered platelets did not bind plasma factor V. The factor V activity of frozen-and-thawed platelet suspensions was markedly diminished after exposure to a factor V antibody, was not activated by thrombin, and was not associated with an increase in factor V antigen over that found in fresh platelet suspensions. Consequently, disruption by freezing and thawing must have resulted in the appearance of small amounts of an activated factor V molecule in platelet suspensions. Disrupted platelets were shown to activate native factor V, but an interaction between a platelet activator and traces of native factor V in fresh suspensions could not be demonstrated to account for the full activity of frozen-and-thawed suspensions. Apparently, therefore, platelets also contained an activated factor V molecule. Adding collagen, but not adenosine 5'-diphosphate to fresh platelet suspensions increased their factor V activity. Release of an activated platelet factor V molecule after exposure to collagen could represent a physiologically significant early step in hemostasis.