cssi/SciSciGPT-SciSciNet huggingface dataset:
How would a latent period for early breast cancer affect the benefit of screening

The ideal goal of a screening program for breast cancer is to detect the disease at a stage when it is still curable by a simple lumpectomy. This goal would be possible if the tumor had an early latent period before it was vascularized. However, even if there existed a harmless screening examination that was sensitive enough to discover the cancer at this stage the benefit to be gained from a screening program would be highly dependent on the time the tumor spends in the latent stage as well as on the chance of false negatives at the examination. Calculations derived from a mathematical model suggest a variety of theoretically possible situations including: (1) For certain cancers screening every three years would offer almost as much benefit as screening every year; (2) A large increase in the sensitivity of a screening examination does not necessarily lead to a large increase in the benefit of a screening program; (3) For certain cancers the benefit of screening might remain low no matter how sensitive the examination used.
ITER safety and operational scenario

Abstract The safety and environmental characteristics of ITER and its operational scenario are described. Fusion has built-in safety characteristics without depending on layers of safety protection systems. Safety considerations are integrated in the design by making use of the intrinsic safety characteristics of fusion adequate to the moderate hazard inventories. In addition to this, a systematic nuclear safety approach has been applied to the design of ITER. The safety assessment of the design shows how ITER will safely accommodate uncertainties, flexibility of plasma operations, and experimental components, which is fundamental in ITER, the first experimental fusion reactor. The operation of ITER will progress step by step from hydrogen plasma operation with low plasma current, low magnetic field, short pulse and low duty factor without fusion power to deuterium–tritium plasma operation with full plasma current, full magnetic field, long pulse and high duty factor with full fusion power. In each step, characteristics of plasma and optimization of plasma operation will be studied which will significantly reduce uncertainties and frequency/severity of plasma transient events in the next step. This approach enhances reliability of ITER operation.
Disease clusters in occupational medicine: a protocol for their investigation in the workplace.

Disease clusters have been an important source of epidemiologic and medical information in the history of occupational medicine. Many accepted disease-exposure linkages were first observed and investigated as disease clusters in the workplace setting. Recent interest in disease cluster methodology has focused on traditional environmental settings. There has been very little work on a similar methodology for the investigation of disease clusters in the workplace, despite the many advantages of workplace cluster investigations for recognizing new etiologic associations. In this paper, a protocol is proposed and discussed which can be implemented in both acute and chronic disease cluster outbreaks in the workplace, where no obvious previously recognized cause is identified. A standardized approach to occupational disease cluster investigation will lead to increase efficiency, decreased social-political tensions, and a greater yield of scientific information. © 1992 Wiley-Liss, Inc.
Direct major- and trace-element analyses of rock varnish by high resolution laser ablation inductively-coupled plasma mass spectrometry (LA-ICPMS)

Laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) was used to determine major and trace element concentrations in rock varnish samples from the Lahontan Range, near Fallon, NV and from a remote wilderness area near the San Juan River, in southeastern Utah. The data indicate that rapid LA-ICPMS analyses provide ample analytical resolution for semi-quantitative compositional determinations of both trace and major elements in the varnish despite the presence of a rock substrate component in most analyses. The overall major element contents of rock varnish from the two localities are grossly similar to rock varnish from other locations analyzed by solution ICPMS, electron microprobe, and energy dispersive scanning electron microscopy (SEM). Differences between microprobe and LA-ICPMS analyses may stem from different sampling scales and different degrees of substrate involvement. It was possible to detect significant variations in trace element contents in the rock varnish samples. The Lahontan Range is situated within a belt of W mineralization, and varnish from that locality contained significantly higher W and Mo contents than varnish from localities outside the W belt. Lead, Tl, Bi, Cd and As contents of varnish-coated pebbles from near the San Juan River in southeastern Utah, varied by an order of magnitude as a function of the position of the sampling site on the pebble. Elevated heavy element contents on the skyward-facing varnish surfaces indicate that heavy elements may be preferentially scavenged at the locations most likely to receive direct inputs of atmospherically-deposited airborne particulates. The source of metal-rich airborne particulates, in this case, is probably any one of several large coal-fired power plants in the Four Corners region, proximal to the San Juan study area. These patterns indicate that rock varnish chemistry is influenced by atmospherically-derived fluxes of both dissolved and particulate constituents, and that rock varnish can be used as a passive environmental indicator for a wide variety of elements, in much the same manner as moss and lichens.
Structure and band gaps of Ga-(V) semiconductors: The challenge of Ga pseudopotentials

Design of gallium pseudopotentials has been investigated for use in density functional calculations of zinc-blende-type cubic phases of GaAs, GaP, and GaN. A converged construction with respect to all-electron results is described. Computed lattice constants, bulk moduli, and band gaps vary significantly depending on pseudopotential construction or exchange-correlation functional. The Kohn-Sham band gap of the Ga-(V) semiconductors exhibits a distinctive and strong sensitivity to lattice constant, with near-linear dependence of gap on lattice constant for larger lattice constants and a $\ensuremath{\Gamma}\text{\ensuremath{-}}X$ crossover that changes the slope of the dependence. This crossover occurs at $\ensuremath{\approx}98$, 101, and 95% deviation from the equilibrium lattice constant for GaAs, GaP, and GaN, respectively.
Optimality of project financing: Theory and empirical implications in finance and accounting

During the 1980s a fairly active market developed in the private placement of limited recourse project financing. Although this form of financing is gaining in importance, we know very little about it. This article presents a theoretical analysis of project financing. In the model of the firm presented, outstanding risky debt gives rise to agency costs of underinvestment that are offset by the benefit of debt-related tax shields. The tradeoff specifies the optimal leverage for a firm. Within this framework, we consider the optimality of financing a new project with a nonrecourse project financing arrangement. We derive implications for 1) the characteristics of a new venture that will be project financed, 2) the wealth gains from project financing over that of financing with straight debt, and 3) the optimal allocation of debt across the different assets (the sponsor firm vs. the new venture). It is shown that a project financing arrangement, where the debt is optimally allocated to the sponsor firm and the new venture, increases value by reducing agency costs and increasing the value of tax shields (compared to the case of straight debt financing). The optimal allocation of debt in project financing involves assigning to the sponsor firm and the new venture debt levels equal to their individual optimal capital structures. Several testable empirical implications in finance and accounting are developed.
Are state growth management programs viable tools for biodiversity conservation? A case study examining Florida local governments

Abstract We examined the quality of Florida's state growth management program and associated county comprehensive plans as an overall biological conservation strategy. A plan evaluation coding protocol using a conceptual framework derived from the science of conservation planning was applied to local comprehensive plan Conservation Elements to determine the extent to which county-level conservation planning met the well-accepted conceptual framework. We found a high degree of variability in the quality of conservation planning for biodiversity, which was related to political geography. The quality of plans in coastal counties was significantly higher than that of inland counties. Significant regional differences were also evident, with conservation planning quality in South Florida counties significantly higher than in Panhandle counties. Geographic differences in the quality of local conservation planning are attributable to socioeconomic differences, education of the public, and availability of resources for planners. A model selection and averaging approach based on information theory was employed to develop a predictive model of conservation planning quality of Florida local governments. The results of this study call into the question the efficacy of state growth management programs as land-use regulatory tools to stem current rapid losses in biological diversity.
Intelligence Generation and Superior Customer Value

It has become conventional wisdom that an organization's ability to continuously generate intelligence about customers' expressed and latent needs, and about how to satisfy those needs, is essential for it to continuously create superior customer value. However, intelligence generation typically has been treated as a generic firm activity. The authors propose that there are four distinct modes of intelligence generation, each of which is part of a welldeveloped intelligence-generation capability. The article reports the results of an exploratory study that supports this proposition.
Chromosome Structure in Amblystoma punctatum

1. The ehromosomes in the epithelial cells of larval salamanders were prepared for study by the use of the smear method. Both acetocarmine and permanent smears were used.2. The chromosomes of Ainblystoma punctatum consist of a matrix in which lies a coiled or zigzag thread. The thread is double at all stages except metaphase when it is quadruple.3. In occasional cells the chromatids are widely separated during prophase and metaphase. A possible explanation for this condition is suggested.
Concentration and Removal of Nitrogen and Sulfur Containing Compounds from Organic Liquid Phases Using Electrochemically Reversed Chemcial Complexation

A process is being developed to concentrate and remove sulphur- and nitrogen- containing compounds from organic liquid phases. These phases could include coal liquids, oil from oil shale or tar sands, as well as conventional crude oil. This process uses reversible complexation and electrolysis. A cyclical contacting scheme is proposed: the compounds are first extracted from a polluted hydrocarbon phase using an aqueous phase containing a complexing agent; the aqueous phase is then contacted with a waste hydrocarbon phase and the complexing agent is oxidized, releasing any complexed pollutants into the waste hydrocarbon phase. This cycle is repeated to extract more pollutants, i.e. sulphur and nitrogen compounds, from the contaminated phase and concentrate them in the waste phase. A description of the process and preliminary results for one system are presented.
University Students’ Perceptions of an Inclusive Music Production:

A total of 130 undergraduate and graduate music education and music therapy students watched a videotape of elementary children with cerebral palsy (CP) and typical peers preparing and performing i...
Salvage laparotomy for failure of peritoneal drainage in necrotizing enterocolitis in infants with extremely low birth weight.

Abstract Background/Purpose: Peritoneal drainage is a temporizing procedure for infants with extremely low birth weight (ELBW) who have perforated necrotizing enterocolitis (NEC). "Salvage" laparotomy is advocated when patients worsen after drainage. Some patients have survived with intact gastrointestinal functional after drainage alone. The purpose of this study is to determine if these salvage laparotomies are beneficial. Methods: The authors reviewed the records of ELBW infants treated at Stanford University with perforated NEC from 1993 through 1998. Data collected included demographic makeup, type of operation, survival rate, postoperative complications, length of stay (LOS), and cost. Results: The authors treated 26 patients, 9 with laparotomy and 17 with peritoneal drainage. The peritoneal drainage group had lower birth weight and more comorbid conditions. Survival rate was similar between laparotomy and drainage: 55.6% versus 41.2%. Four patients in the drainage group underwent salvage laparotomy for perceived clinical deterioration. All of these patients died. The clinical status of patients who had salvage laparotomy and died was similar to those who did not and lived. Seven of 13 patients treated with drainage followed only by supportive care and antibiotics survived. Cost and LOS for patients undergoing salvage laparotomy were much greater than for nonsurviving patients undergoing only peritoneal drainage: 84 ± 20 days and $660,000 compared with 34 ± 11 days and $306,000. Conclusions: Both primary peritoneal drainage and laparotomy should be considered primary therapy for perforated NEC. Patients undergoing peritoneal drainage typically experience clinical deterioration after operation. In this limited experience, salvage laparotomy did not appear beneficial. J Pediatr Surg 35:856-859. Copyright © 2000 by W.B. Saunders Company.
Dynamics of uptake and channeling of arachidonic acid in hamster alveolar macrophages and the effect of bleomycin on arachidonyl distribution.

Abstract The uptake and distribution of [ 14 C]-arachidonic acid (AA) by primary culture hamster alveolar macrophages (AM) were examined. The macrophages were incubated for 2 to 18 hrs in RPMI-1640 medium containing 0.1% BSA and [ 14 C]-AA. The uptake of [ 14 C]-AA by AM was rapid with 71% and 83% of exogenous [ 14 C]-AA taken up after 2 and 4 hrs of incubation, respectively. Initially, the uptaken [ 14 C]-AA was equally distributed between phospholipids (PL) and neutral lipids (NL). However, by 8 hrs, 86% and 14% of [ 14 C]-AA was found in PL and NL, respectively. This distribution pattern remained constant through 18 hrs. Within the PL pool, most of the [ 14 C]-AA was initially incorporated into phosphatidylcholine (PC). However, with time, as the percent of [ 14 C]-AA incorporated in PC declined, the percent incorporated in phosphatidylethanolamine increased. The incorporation of [ 14 C]-AA into sphingomyelin, phosphatidylinositol, and phosphatidylserine remained constant with time. Within the NL, most of the [ 14 C]-AA was initially found incorporated into triacylglycerols (TG). After 4 hrs, the percent of [ 14 C]-AA found in TG decreased markedly, while the percent found in cholesterol esters markedly increased. Incubation of AM prelabeled with [ 14 C]-AA with bleomycin at 0.5, 5, 50 and 500 μM for 2 and 8 hrs failed to have any effect on the distribution of [ 14 C]-AA in PL and NL pools.
Parameterization of Curvilinear Spars and Ribs for Optimum Wing Structural Design

A parameterization of the aircraft shape is needed for a correct mathematical definition of the structure and its components. The parameterization allows the definition of the geometry as a function of a few meaningful parameters. Traditionally, the aircraft industry focused on developing a universal parameterization of the aircraft outer mold line to facilitate the automatic construction of complex aerodynamic meshes to be used in computational fluid dynamics calculations and aerodynamic shape optimization problems. More recently, the attention of researchers has shifted toward the internal structure topology parameterization. The introduction of new design concepts such as SpaRibs (spars and ribs) requires the capability to define the geometric shape of the internal wing components for a correct automatic generation of the finite element mesh. The aim of this research is to present a simple and efficient way to parameterize the topology of the internal structure of complex wings. Spline curves are used ...
Remote infrared chemical sensing using highly durable AlF(3)-based glass fibers.

Unclad, low-loss AlF3-based glass fibers with enhanced chemical durability have been successfully used for the first time to our knowledge as intrinsic evanescent infrared sensors for monitoring liquid chemicals. Different liquids with absorption bands between 1 and 4.5 μm, such as alcohol, acetonitrile, and mixtures of alcohol/acetonitrile and water/acetonitrile, have been tested. These fibers have also been used successfully as distributed sensors for simultaneous monitoring of different chemical species.
The Homogeneous Oxidation of Acetylene

FOR many years the slow oxidation of hydrocarbons has been thought to be a reaction taking place at a surface. We have succeeded in demonstrating the wholly homogeneous character of a hydrocarbon oxidation and have obtained conclusive proof of the chain nature of the reaction. Just as this work was completed, Mr. C. N. Hinsheiwood, of Oxford, informed us privately that he had obtained similar evidence for hydrocarbon oxidation, which is to be published shortly.1
Asymmetry of Subinsular Anisotropy by in vivo Diffusion Tensor Imaging

The cortical regions specialized in speech-language exhibit a left-right asymmetry, e.g., a larger cortical size in the left auditory cortex and Wernicke's area. The possibility of developmental asymmetry in axonal fibers interconnecting speech-language cortical areas can be investigated by in vivo diffusion tensor imaging. Fifteen right-handed native English speakers showed a markedly significant asymmetry (P < 0. 0005) in the relative anisotropy of water diffusion in the subinsular white matter, greater on the left. Additionally, the first principal diffusivity was greater and the second and third principal diffusivities were smaller on the left than right side. These results suggest the subinsular axonal structures developed differently between the left and right sides. A possible association between the hemispheric specialization in language and speech and the subinsular axonal fiber development is discussed.
Day and Night Foraging of Red Knots (Calidris canutus) during Spring Stopover in Virginia, USA

Abstract. Long-jump migrant shorebirds have brief windows during spring stopover to acquire the energy needed to complete migration. Red Knots (Calidris canutus) refueling on Horseshoe Crab (Limulus polyphemus) eggs in Delaware Bay can meet their energy needs foraging only by day. In nearby Virginia, thousands of Red Knots stop over, but primarily low-quality, hard-shelled prey are available. One tactic Red Knots may use to meet their energy demands with such prey might be to extend their foraging time by feeding at night. To estimate the length of the foraging day in Virginia, daylight feeding was studied during three spring stopover periods (2008 to 2010), and night feeding was studied in 2010. Red Knots foraged 76 ± 3 SE% of the time in 2008 and 2009 combined, and 59 ± 3% of the time in 2010, during 3-minute observations. In 2010, Red Knots foraged 51 ± 7% of the time during a continuous 7-h daytime observation and 77 ± 5% of the time during a continuous 8-h night time observation on the same island. G...
The application of double potential-step chronocoulometry to the study of catalytic reactions : the Ti(III)-hydroxy lamine reaction

Abstract The theoretical relationships for the double potential-step chronocoulometry applied to the study of catalytic reactions were verified by an investigation of the Ti(III)-hydroxylamine reaction. The kinetic para-meters obtained in this investigation are: K298 = 43.4±1.1 l/mole sec Ea = 17.2± 1.1 kcal/mole where k298 is the rate constant at 25° and Ea is the Airhenius energy. Previously-reported values of k298 are in excellent agreement with the value reported here but the previously-reported value for the Arrhenius energy appears to be inexplicably in error.
Decreases in renin and aldosterone secretion in alloxan diabetes: an effect of insulin deficiency.

The effect in the rat of alloxan diabetes (with and without insulin treatment) on renin and aldosterone secretion was examined. Rats with diabetes for 7 weeks were found to have lower PRA than nondiabetic controls. The decrease in PRA appeared to result from insulin deficiency since PRA was normal in diabetic rats given insulin. In a second set of animals, which were killed after 3 weeks, in vitro measurements of aldosterone production by perifused adrenal capsular tissue were carried out. Production of aldosterone was greatest by adrenal capsular tissue from insulin-treated diabetic rats where both basal and potassium-stimulated aldosterone production were higher than diabetic rats not given insulin. Although the reduced aldosterone production associated with untreated diabetes may have been a result of reduced in vivo exposure of adrenal tissue to angiotensin II, a chronic adrenotrophic influence of insulin could not be ruled out. In summary, insulin appears to be necessary for normal renin and aldoster...
Characterization and modeling of the mechanical behavior and formability of a 2008-T4 sheet sample

Abstract A 2008-T4 sheet sample has been characterized and its mechanical behavior and formability have been modeled. Uniaxial tensile and equal biaxial tensile stress-strain data, compressive yield strengths, crystallographic texture, earing and the forming limit curve were experimentally determined. Bulge test specimen shape and thickness profiles were also measured after various amounts of biaxial strain. A recently developed phenomenological constitutive model of anisotropic mechanical behavior was used to predict the directionality of strength, plastic strain ratio ( R ) and shear strain ratio (Г) values. In addition, this model was used to predict the forming limit curve for this sample. Predictions made with the recent model generally compare favorably with experimental results and with predictions made using the Taylor/Bishop and Hill theory. According to the data obtained in hydraulic bulge testing, the 2008-T4 exhibited apparent isotropic behavior. However, in cup drawing—another axisymmetric deformation mode—this material exhibited anisotropic behavior, as indicated by the formation of ears and troughs.
On the use of the transmembrane domain of bacteriorhodopsin as a template for modeling the three-dimensional structure of guanine nucleotide-binding regulatory protein-coupled receptors.

Abstract The molecular architecture of bacteriorhodopsin (BR) is commonly regarded as a structural template for the three-dimensional structure of membrane receptors that are functionally coupled to guanine nucleotide-binding regulatory proteins (GPCR). More recently, specific molecular models of such GPCR were constructed on the basis of the functional and structural relation of rhodopsin to BR as well as the sequence homology between rhodopsin and the GPCR. Such models of GPCR leave unresolved the difficulty caused by the apparent lack of any significant degree of sequence homology between the seven transmembrane helices (TMH) of BR and the portions in the sequence of the various GPCR that are considered to constitute their transmembrane domains. Evolutionary arguments offered in favor of the structural relation between BR and the opsins, and hence the GPCR, prompted our investigation of the possibility that the sequence homology, including any similarity in the distribution of kink-inducing proline residues among the helices, might have been obscured by the assumption that the TMH maintained their sequential order from BR in the evolution of the mammalian proteins. With a definition of the TMH in the neurotransmitter GPCR guided by hydropathicity predictions, and additional criteria used to define the span of each helix, optimal alignment of each pair of sequences was determined with no gaps allowed in the matching. The resulting alignment proposed here reveals considerable homology between the TMH in BR and those in GPCR, if the sequential order of the helices is ignored. These findings suggest the possibility that exon shuffling could have occurred in the proposed evolution of the GPCR gene from BR and point to a modification of the BR template to account for the correct packing of the helices in the tertiary structures of GPCR. These findings could guide the construction of three-dimensional models of the neurotransmitter GPCR on the basis of specific interhelical interactions observed in BR.
A Comparison of Three Joint Ordering Inventory Policies

This paper evaluates the performance of a joint ordering inventory policy which was first suggested and characterized by Renberg and Planche [14]. This paper shows that the policy is easily characterized for Poisson demands. This policy is then compared with two other joint ordering policies—the well-known (S, c, s) or can-order policy of Balintfy [3] and the recent periodic policies suggested by Atkins and lyogun [2]. For a continuous review operating environment, the Renberg and Planche policy utilizes a group reorder point and a combined order quantity (Q), with each item maintaining an order-up-to level (S). For the can-order policy, each item in the product group has a must-order point (s), a can-order point (c) and an order-up-to level (S). The periodic policies require that item orders be grouped at some fixed scheduled intervals. Using long-run total average costs as the basis, it is shown that no one policy is superior to the others in all the examples tested. In some cases, the Renberg and Planche policy performs surprisingly well.
Petrology of a portion of the Eastern Peninsular Ranges mylonite zone, Southern California

Peraluminous and metaluminous plutonic rocks of the Peninsular Ranges batholith near Borrego Springs in southern California were mylonitized in the large shear zone known as the eastern Peninsular Ranges mylonite zone (EPRMZ). Accompanying mylonitization in this portion of the EPRMZ was metamorphism at intermediate-low-pressure amphibolite-facies conditions. Deformation in the zone overlapped in time with Cretaceous intrusion of the batholith. In the San Ysidro Mountain — Pinyon Ridge area, four north-south trending zones of differing intensity of deformation have been defined; from east to west the degree and style of deformation gradually change from undeformed or weakly deformed rocks to strongly mylonitized rocks. Electron microprobe analysis shows that recrystallized hornblende, biotite, and plagioclase are variable in composition, probably reflecting a range of metamorphic conditions accompanying deformation. Comparison of mineral compositions with those from mafic schists of Vermont suggests conditions ranged from andalusite-staurolite through sillimanite-muscovite grades as defined for pelitic rocks. Stability of muscovite+quartz in mylonite assemblages and lack of remelting of granitic rocks indicate that temperature did not exceed about 650° C during mylonitization and lithostatic pressure did not exceed about 5 kbar. Over time, any given rock volume experienced a range of temperature, lithostatic pressure, and perhaps fluid pressure and differential stress. Mineral reactions in the zone involved hydration, requiring introduction of water. The possibility of large-scale migration of K and Fe is suggested by whole-rock chemical data. Brittle and ductile deformation features are closely associated in one part of the EPRMZ. The combined evidence suggests the presence of a pore fluid with fluid pressure close to lithostatic pressure. Short periods of low fluid pressure and possible high differential stress cannot be ruled out.
Effects of concentration dependent diffusivity on the growth of precursing films of Pb on Cu(1 1 1)

Abstract The diffusion of Pb away from partially wetting Pb particles on the Cu(1 1 1) surface to form so-called precursing films has been studied by means of Auger electron spectroscopy at temperatures in the range 353–373 K. These films achieve a maximum thickness of about 0.85 Pb monolayers (0.85 ML) at the particle triple line. The surface concentration profiles of Pb in the vicinity of particles have been analyzed to extract the diffusion coefficient ( D ) as a function of coverage at various temperatures. D exhibits high values both at low ( 0.5 ML) Pb coverages, and a minimum near 0.5 ML. This dependence of D on coverage is consistent with the surface structures known to be present on Cu(1 1 1) at various Pb coverages. In particular, the low value of D at intermediate coverage is associated with the incorporation of Pb into the Cu surface in the form of a surface alloy. The time dependence for growth of the precursing film is very similar to the kinetics of precursing film growth in much more complex molecular systems. Our observations of a monolayer precursing film in quasi-equilibrium with a partially wetting particle are consistent with models of the relationship between precursing films and contact angles.
Information technology personnel layoffs in US organizations: An exploratory investigation

The new century has been marked by an unprecedented number of layoffs of IT personnel. But despite the increasing industry concerns over IT worker downsizing, the knowledge base and scholarly literature on IT personnel layoffs has been sparse. This paper suggests some exploratory, descriptive insights into such downsizing efforts. Data on 569 layoff events in the US for years 2000 and 2001 were gathered and analyzed to help gain an understanding of the phenomenon. We examined the trends in IT personnel layoffs over time, across different industries, their nature and extent, the stated reasons given for downsizing and the financial environment of firms laying off IT workers. The findings and their implications are discussed.
Molecular targets for AIDS therapy

The development of antiretroviral therapy against acquired immunodeficiency syndrome (AIDS) has been an intense research effort since the discovery of the causative agent, human immunodeficiency virus (HIV). A large array of drugs and biologic substances can inhibit HIV replication in vitro. Nucleoside analogs--particularly those belonging to the dideoxynucleoside family--can inhibit reverse transcriptase after anabolic phosphorylation. 3'-Azido-2',3'-dideoxythymidine (AZT) was the first such drug tested in individuals with AIDS, and considerable knowledge of structure-activity relations has emerged for this class of drugs. However, virtually every step in the replication of HIV could serve as a target for a new therapeutic intervention. In the future, non-nucleoside-type drugs will likely become more important in the experimental therapy of AIDS, and antiretroviral therapy will exert major effects against the morbidity and mortality caused by HIV.
Calorie-Protein Deficiencies and the Immune Response of the Chicken I. Humoral Immunity

Abstract How dependent is the chicken on the calorie (C) and amino acid (AA) levels of the diet? This question was addressed by formulating diets that were two-thirds deficient in C and AA. Feeding the one-third C–one-third AA, one-third C and one-third AA diets for 5 weeks, in general, reduced the primary response to 5% sheep red blood cells (SRBC) but not to .5% SRBC. The C/AA deficient birds were returned to a basal diet at 5 weeks and three weeks later reimmunized with SRBC. The secondary response, immunoglobulin G (IgG) titer, of the latter birds after 3 weeks on a basal diet was significantly lower than controls. Total serum protein was significantly depressed during the feeding of one-third AA diet. Transferrin, IgG, and IgM were not affected while albumin was significantly reduced. Gain in body weight was reduced in all groups receiving the C/AA deficient diets. Three weeks after repletion, all groups gained equally.
Responses of normally innervated soleus muscle to supplementary nerve implantation

Abstract It has been reported that when the proximal end of a transected nerve to a fast-twitch muscle is implanted into a normally innervated rat soleus muscle, changes are induced in the soleus indicative of muscle hypertrophy and speeding of its dynamic properties. To test these findings, in nine rats (group I) the nerve to the flexor digitorum longus was severed and implanted into the normally innervated soleus muscle of one leg. In the contralateral leg, the flexor digitorum longus nerve was implanted into the medial gastrocnemius to prevent reinnervation of the flexor digitorum longus. Two additional groups of rats also underwent flexor digitorum longus nerve implantation into the normal soleus. In group II the implanted nerve was sutured to the soleus, and in group III it was “glued” to the muscle using a thrombin-fibrinogen clot. The contralateral control legs of these latter two groups were left intact. With the three groups of animals it was possible to compare both nerve implantation and synergist denervation with unoperated muscle. An 8% (P
Paradoxes of immunosuppression in mouse models of withdrawal.

Abstract Previously, our laboratory showed that either abrupt (AW) or precipitated withdrawal (PW) from morphine led to profound suppression of murine splenic antibody responses to sheep red blood cells at 24 h post-withdrawal. In the present studies, we examined the immune mechanisms mediating suppression at that time point. A co-culture method was used to examine whether cells from withdrawn mice had (1) a deficit in function and/or (2) contained populations of suppressor cells. To examine the first hypothesis, cells from normal mice were co-cultured with cells from withdrawn mice in a 1:3 ratio (normal/withdrawn). To test the second hypothesis, the ratio was reversed. The results were paradoxical. Co-culture of cells in a 1:3 ratio showed that spleen cells from withdrawn mice had a deficit in macrophage function. Spleen cells from withdrawn mice also showed decreased mRNA levels of IL-1β, IL-1-Ra, and TNF-α and a suppression of co-stimulatory molecule expression. To examine the second hypothesis, cells were co-cultured in a 3:1 ratio (normal/withdrawn). In this paradigm, spleen cells from abrupt withdrawn mice were shown to contain populations of both suppressor macrophages and B-cells. In vivo experiments carried out on mice 24 h post-withdrawal showed increased sensitivity to the lethal effects of LPS and increased production of TNF-α, implying a state of macrophage activation. Thus evidence for both suppressed and activated macrophages has been obtained in mice 24 h after abrupt withdrawal from morphine.
BLACK-BOX MODELS OF CANDIDATE EVALUATION

All contemporary models of candidate evaluation are memory-based models in that they treat the direction and strength of evaluation as a function of the mix of positively and negatively valued (valenced) information retrieved from memory. Yet, oddly enough, despite the assumption that memory mediates judgment, none of the major models looks at the processes involved in what information voters recall and how that evidence was integrated into a summary evaluation. In this sense then, political science models of vote choice are black-box models: They are silent about how voters actually go about interpreting information and integrating the “evidence” into a summary evaluation of the candidates. In this article we critique the major political science models, call attention to the implicit assumptions they make about what “evidence” is assumed to be in memory, and conclude with an argument for introducing process into our explanations of vote choice.
Safety of embedded software

Traditional safety techniques were created 40-50 years ago for electro-mechanical systems. The underlying assumptions of these techniques about the cause of accidents (e.g., component failure) do not match software nor do they match the types of accidents we are having that are related to software. As a result, a large number of accidents are now related to software, although usually the pilot (for aircraft) or other human operators are blamed. Often, the software design leads to the operator errors. We will describe the problems with software that are leading to accidents (primarily in the requirements) and how to deal with them. Most of the current approaches rely on reducing "failures" although software does not fail. Something else is needed.In the tutorial we will present a new accident causality model (STAMP) and teach how to use a new hazard analysis technique (STPA) based on it that can be used on complex, software-intensive systems. The topics will include how to generate software safety requirements from an STPA hazard analysis and how to design software that does not induce human error. The tutorial will be based on a new book, Engineering a Safer World by Nancy Leveson and published in January 2012 by MIT Press.
Dietary composition and nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is a common and potentially serious form of chronic liver disease that occurs in patients who do not abuse alcohol. Present dietary recommendations for all Americans, including those with NAFLD, endorse a low-calorie, low-fat diet. However, little is known about the effect of diet composition on liver histopathology in patients with NAFLD. The aim of this study was to determine whether overall calorie intake and diet composition are associated with the severity of NAFLD histopathology. Seventy-four consecutive morbidly obese patients presenting for bariatric surgery from January 2001 to March 2002 were retrospectively reviewed. In addition to a standard surgical and psychological evaluation, all patients underwent a preoperative dietary evaluation using a standardized 24-hr food recall. Food intake was evaluated for total calories and macronutrients and compared to liver histopathology from biopsies routinely obtained during surgery. Associations with the severity of steatosis and the presence of inflammation or fibrosis were assessed separately using chi-square for categorical variables and ANOVA for continuous variables. Further, we conducted multiple logistic regression analyses for each histological outcome. There were no significant associations between either total caloric intake or protein intake and either steatosis, fibrosis, or inflammation. However, higher CHO intake was associated with significantly higher odds of inflammation, while higher fat intake was associated with significantly lower odds of inflammation. In conclusion, present dietary recommendations may worsen NAFLD histopathology.
Development of a Preliminary Model-Scale Adaptive Jet Engine Chevron

Reduction of jet noise continues to be an important research topic. Exhaust-nozzle chevrons have been shown to reduce jet noise, but parametric effects, including immersion amount and azimuthal distribution, are not well understood. Additionally, thrust loss due to static chevrons at cruise suggests a significant benefit from deployable chevrons. The focus of this study is the development of an adaptive-chevron concept for the primary purpose of parametric studies for jet noise reduction in the laboratory and secondarily for development of technology that can be leveraged for full-scale systems. The adaptive-chevron concept employed in this work consists of a laminated composite structure with embedded shape memory alloy actuators. The actuators are embedded on one side of the middle surface such that joule heating of the actuators causes them to attempt recovery of prestrain, thereby generating a moment and deflecting the structure. A brief description of the chevron design is given followed by details of the fabrication approach. Results from bench-top tests are presented and correlated with numerical predictions from a model for such structures that was previously implemented in MSC.Nastran and ABAQUS. Excellent performance and agreement with predictions is demonstrated. Results from tests in a representative flow environment are also presented. Excellent performance is again achieved for both open- and closed-loop tests, the latter demonstrating control of deflection to a specified immersion into the flow. The actuation authority and immersion performance is shown to be relatively insensitive to nozzle pressure ratio. Very repeatable immersion control with modest power requirements is demonstrated.
Leisure routines: Parents and children with disability sharing occupation

This phenomenological study describes occupations within family leisure routines that parents choose to share with their children. Nine parents caring for children who are unable to participate independently in self care and leisure pursuits due to multiple disabilities contributed to the study. Individual interviews using 10 open ended questions were completed to explore the cultural, temporal and environmental elements of these occupations that hold meaning for the parents. Both descriptive and interpretive qualitative analyses were used to ascertain patterns or themes within the narratives. The three themes that emerged reflect how sharing leisure routines created (1) opportunities for moments of happiness, (2) moments of normalcy and (3) moments of control of one's life and environment. These parental perspectives shed light on the ways shared leisure occupations sustain health and well‐being for parents coping with the responsibility of caring for a child with disability.
Ternary diffusion of gases in capillaries in the transition region between knudsen and molecular diffusion

Abstract Diffusion of a ternary gas mixture in the transition region of diffusion was experimentally investigated in an isobaric open system of fine glass capillaries in parallel. The flux data for HeNeAr were obtained over a 673/1 pressure range from 0·450 to 303·2 mm Hg abs. in the transition region between molecular (ordinary) and Knudsen diffusion and confirm the integrated theoretical equations in true capillaries for a ternary mixture. This appears to be the first experimental confirmation of these equations over a wide pressure range. The use of binary transition equations to approximate the ternary flux values throughout the transition region is demonstrated. Approximate methods are presented to calculate the ternary flux values at different boundary conditions or driving forces.
Direct investigation of anisotropic suspension structure in pressure-driven flow

Evidence is presented to show the microstructural anisotropy responsible for normal stress in sheared suspensions. Particle velocimetry is combined with three-dimensional particle locations obtained via confocal microscopy at rest. A range of volume fractions $\ensuremath{\phi}$ and local shear rates $\stackrel{\ifmmode \dot{}\else \.{}\fi{}}{\ensuremath{\gamma}}$ are investigated in a weakly Brownian pressure-driven suspension. At high $\stackrel{\ifmmode \dot{}\else \.{}\fi{}}{\ensuremath{\gamma}}$, the pairwise distribution shows a strong probability along the axis of compression similar to observations from Stokesian dynamics simulation at $\ensuremath{\phi}=0.32$. At the channel center where $\stackrel{\ifmmode \dot{}\else \.{}\fi{}}{\ensuremath{\gamma}}\ensuremath{\rightarrow}0$, the concentrated suspension at $\ensuremath{\phi}=0.56$ behaves as a confined isotropic fluid.
Effects of thyrotropin and thiouracil on the sialic acid concentration in the thyroid gland.

Abstract An investigation was made of sialic acid in the thyroid gland. A preparation of calf thyroglobulin which was homogeneous in the ultracentrifuge contained 1.2% sialic acid. Stimulation of the thyroid gland of the rat to cause resorption of colloid was accompanied by a decrease in the thyroidal sialic acid concentration. After feeding thiouracil for 2 days, the time when the rate of decrease of the sialic acid concentration was maximal, there was a doubling of the concentration of free sialic acid in the thyroid. The sialic acid was identified to be N-acetylneuraminic acid.
The Asante-Based Afrocentricity Scale: Developing a Scale to Measure Asante's Afrocentricity Paradigm

This exploratory study produced a 24-item Afrocentricity scale to measure foundational concepts within Molefi Asante's Afrocentricity paradigm. A non-random sample of 380 respondents was used to pilot the scale, resulting in three dimensions. Reliability analysis shows the scale's internal consistency, factor analysis and mean comparisons provided support for the scale's validity. Moving toward the development of a valid and reliable Afrocentricity scale can assist in helping professions of psychology, social work, and health in research and practice. Future research should examine whether the three interpreted dimensions within this scale structure can be replicated across different samples.
Characterization and mitigation of coherent-optical-transition-radiation signals from a compressed electron beam

The Advanced Photon Source (APS) injector complex includes an option for rf photocathode (PC) gun beam injection into the 450-MeV S-band linac. At the 150-MeV point, a four-dipole chicane was used to compress the micropulse bunch length from a few ps to sub-0.5 ps (FWHM). Noticeable enhancements of the optical transition radiation (OTR) signal sampled after the APS chicane were then observed as has been reported in the Linac Coherent Light Source (LCLS) injector commissioning. A far-infrared (FIR) coherent transition radiation detector and interferometer were used to monitor the bunch compression process and correlate the appearance of localized spikes of OTR signal (5 to 10 times brighter than adjacent areas) within the beam-image footprint. We have performed spectral-dependency measurements at 375 MeV with a series of bandpass filters centered in 50-nm increments from 400 to 700 nm and with an imaging spectrometer and observed a broadband enhancement in these spikes. Mitigation concepts of the observed coherent OTR, which exhibits an intensity enhancement in the red part of the visible spectrum as compared to incoherent OTR, are described.
An event history analysis of recurrent child maltreatment reports in Florida.

Abstract Objective: The purpose of this study was to (a) describe the timing of maltreatment recurrence and (b) measure associations between child demographics and characteristics of initial reports with recurrent maltreatment. Method: Using administrative data from the Florida Department of Children and Families, case histories of 189,375 children with an initial maltreatment report in 1998 or 1999 were examined using event history techniques, also known as survival analysis, to assess the relationship between predictor variables and the likelihood and timing of recurrence. Specifically, data were analyzed using descriptive and multivariate analytic methods, including life-table analysis and logistic regression analysis. Results: Over 26% of the sample had a maltreatment recurrence during the 2-year follow-up period, and the risk of recurrence was greatest in the first 4 months after the initial incident. Results also suggest the presence of unique associations between recurrence and a child's race/ethnicity and age, as well as indication level, maltreatment type, and service disposition as specified in the initial report. Conclusions: Results indicate that recurrent reports are more likely for young and White children whose first report resulted in a substantiation of neglect and the provision of in-home preventive services. This research highlights the importance of further investigating the relationship between chronic maltreatment and other influential variables.