cssi/SciSciGPT-SciSciNet huggingface dataset:
Liver resection versus chemoembolization for patients with multifocal hepatocellular carcinoma.

Curative intent treatment strategies for patients with hepatocellular carcinoma (HCC) include liver resection, liver transplantation, and arguably tumor ablation. Locoregional therapies including transarterial chemoembolization (TACE) as well as transarterial radioembolization (TARE) remain viable treatment options for patients who are not candidates for therapy with curative intent or patients awaiting liver transplantation receiving downstaging treatment as part of intention to proceed with transplantation.
Near-Unity Light Collection Efficiency from Quantum Emitters in Boron Nitride by Coupling to Metallo-Dielectric Antennas.

The bright and stable single-photon emission under room temperature conditions from color centers in hexagonal boron nitride (hBN) is considered as one of the most promising quantum light sources f...
The Effects of Chronic Preoperative Opioid Use on Single-level Lumbar Fusion Outcomes.

STUDY DESIGN A retrospective study using a national insurance claims database. OBJECTIVE The objective of this study was to assess the relationship between chronic preoperative opioids and the outcomes of revision surgery and nonunion after single-level lumbar fusion. SUMMARY OF BACKGROUND DATA Opioids are widely utilized for pain management before spine procedures. Studies have associated opioids with unfavorable postoperative outcomes, and animal models have also linked opioid administration with unstable bone healing. METHODS Single-level lumbar fusion patients were identified. Patients with any fracture history within 1 year before surgery were excluded. A chronic preoperative opioid cohort was defined by opioids prescriptions within 3 months prior and within 4-6 months before surgery. The rates of revision surgery within 6 months and nonunion within 6-24 months after surgery were assessed. Univariate analyses of chronic preoperative opioid prescriptions and various comorbidities for revision and nonunion were conducted followed by multivariate analyses controlling for these factors. Individual analyses were run for each of the 3 single-level lumbar fusion procedures. RESULTS A total of 8494 single-level lumbar fusion patients were identified. Of the 3929 (46.3%) patients filled criteria for the chronic preoperative opioid cohort, while 3250 (38.3%) patients had no opioid prescriptions within 6 months before surgery. The opioid cohort experienced significantly higher rates of both revisions (3.92% vs. 2.71%, P=0.005) and nonunion (3.84% vs. 2.89%, P=0.027) relative to the opioid-naive cohort. In the multivariate analyses, chronic preoperative opioids were identified as an independent risk factor for revision (odds ratio: 1.453, P=0.006). CONCLUSIONS We report that chronic opioid prescriptions before lumbar fusion may increase the risk of revision. Although these prescriptions were also associated with increased nonunion, the comparisons did not achieve statistical significance in the multivariate model. Chronic preoperative opioid use may be considered a potential risk factor in arthrodesis populations.
COVID-19 outcomes among people with intellectual and developmental disability living in residential group homes in New York State.

Abstract Background People with intellectual and developmental disabilities (IDD) may be at higher risk of severe outcomes from COVID-19. Objective To describe COVID-19 outcomes among people with IDD living in residential groups homes in the state of New York and the general population of New York State. Methods Data for people with IDD are from a coalition of organizations providing over half of the residential services for the state of New York, and from the New York State Department of Health. Analysis describes COVID-19 case rates, case-fatality, and mortality among people with IDD living in residential group homes and New York State through May 28, 2020. Results People with IDD living in residential group homes were at greater risk of severe COVID-19 outcomes: case rates – 7,841 per 100,000 for people with IDD compared to 1,910 for New York State; case-fatality – 15.0% for people with IDD compared to 7.9% for New York State; and mortality rate – 1,175 per 100,000 for people with IDD compared to 151 per 100,000 for New York State. Differences in cases and mortality rate were confirmed across regions of the state, but case-fatality rate was only higher for people with IDD in and around the New York City region. Conclusions COVID-19 appears to present a greater risk to people with IDD, especially those living in congregate settings. A full understanding of the severity of this risk will not be possible until US states begin publicly sharing all relevant data they have on COVID-19 outcomes among this population.
Synergy between Wsp1 and Dip1 may initiate assembly of endocytic actin networks

Abstract The actin filament nucleator Arp2/3 complex is activated at cortical sites in S. pombe to assemble branched actin networks that drive endocytosis. Arp2/3 complex activators Wsp1 and Dip1 are required for proper actin assembly at endocytic sites, but how they coordinately control Arp2/3-mediated actin assembly is unknown. Alone, Dip1 activates Arp2/3 complex without preexisting actin filaments to nucleate “seed” filaments that activate Wsp1-bound Arp2/3 complex, thereby initiating branched actin network assembly. In contrast, because Wsp1 requires pre-existing filaments to activate, it has been assumed to function exclusively in propagating actin networks by stimulating branching from pre-existing filaments. Here we show that Wsp1 is important not only for propagation, but also for initiation of endocytic actin networks. Using single molecule TIRF microscopy we show that Wsp1 synergizes with Dip1 to co-activate Arp2/3 complex. Synergistic coactivation does not require pre-existing actin filaments, explaining how Wsp1 contributes to actin network initiation in cells.
Quasiparticle self-consistent G W energy band calculations for Ge 3 N 4 phases

Quasiparticle self-consistent $GW$ (G Green's function, W screened Coulomb interaction) band structure calculations are presented for the $\ensuremath{\alpha}, \ensuremath{\beta}$, and $\ensuremath{\gamma}$ phases of ${\mathrm{Ge}}_{3}{\mathrm{N}}_{4}$. The $GW$ corrections to the gap are substantial and the gaps are found to be 3.85, 3.86, and 3.56 eV for $\ensuremath{\alpha}, \ensuremath{\beta}, \ensuremath{\gamma}$ respectively, at the experimental lattice constants. Only the $\ensuremath{\beta}$ phase has a direct gap. The $\ensuremath{\alpha}$ and $\ensuremath{\beta}$ phases, which are closely related to each other in crystal structure, are consequently also found to have rather similar band structures. Nonetheless, some significant differences are found near the valence band maximum, which are related to the different interlayer interactions in the $c$ direction. In the cubic spinel phase, the conduction band minima of $s$ and $p$ character are found close to each other. Effective masses are calculated for the relevant valence and conduction band edges and for the cubic case analyzed in terms of the Kohn-Luttinger effective Hamiltonian. The optical response functions from direct interband transitions are calculated.
Sex Differences in Age at Onset and Presentation of Trichotillomania and Trichobezoar: A 120-Year Systematic Review of Cases

Trichotillomania (hair-pulling disorder) has high female preponderance. It has been suggested that onset in early childhood represents a distinct developmental subtype that is characterized by higher prevalence of males compared to later onset cases. However, the empirical literature is scarce. We conducted a systematic review of case reports to examine the distribution of age at onset/presentation in males and females with trichotillomania or trichobezoar (a mass of hair in the gastrointestinal tract resulting from ingesting hair). We identified 1065 individuals with trichotillomania and 1248 with trichobezoar. In both samples, males, compared to females, had earlier age at presentation and greater proportion of cases in early childhood. These sex differences remained after potential confounding variables were accounted for. The results showed similar sex differences for age at onset, which was reported in 734 and 337 of the trichotillomania and trichobezoar cases, respectively. The findings may reflect neurodevelopmental underpinnings in early childhood trichotillomania.
Formal Categorization of Variants for Question Generators in Computer-Based Assessments

With many Universities and Institutions moving toward online learning during the pandemic, content delivery and assessment become a new challenge for many educators. It comes as no surprise that many tools aimed at delivering computer-based assessments have become popular and are fields of active research. Members of the ACE Lab at UC Berkeley are creating question generators for computer science classes on a platform called PrairieLearn, to generate different randomized variants of questions. This poster discusses our team's approach to question variant categorization, which we believe would be useful metadata for other educators reusing our questions or generating their own.
Mapping applications onto a cache coherent multiprocessor

The authors present a technique to compute the communication times of programs on cache coherent distributed shared memory systems. Simulated annealing is used to obtain near-optimal mappings of program tasks onto processors. Various cost parameters are explored for determining efficient mappings of the program tasks onto the processors in the presence of cache coherence protocols. The techniques were demonstrated using the Sequent Balance multiprocessor and the Jacobi iteration problem. Measurement results confirm that the estimate of communication time is fairly accurate. The importance of accurate estimation of communication time for efficient mapping of program tasks in the presence of the cache coherence protocol was verified using measurements on the Balance multiprocessor.
Effects of an Informal Energy Exhibit on Knowledge and Attitudes of Fourth Grade Students

The public has limited knowledge of renewable energy technologies. An increase in energy literacy can potentially lead to desired energy-related behavioral changes in the future. One potential solution is to increase the public’s access to renewable energy information by placing informal energy education exhibits in libraries, community centers, and parks. After calibrating the exhibit based on observations of children’s interactions at a children’s museum, the exhibit was displayed at a university, a private school, and a community center. The opinion surveys and interviews both showed that participants enjoyed and learned from the exhibit. Students showed no significant statistical improvement between the pretests and posttests, but interviews showed that they could recall facts, explain processes, and make inferences from the exhibit. Fourth-grade students can benefit from interacting with an informal energy exhibit in order to increase their knowledge of energy topics and technologies.
Platelet Damaging Factor, a Fifth Activity of Staphylococcal α-Toxin

Crude and purified staphylococcal alpha-toxin were used to demonstrate that the platelet-damaging effect of crude alpha-toxin represents a fifth activity of the alpha-toxin molecule. The homogeneity of the purified toxin employed was demonstrated by ultracentrifugation, Ouchterlony, and immunoelectrophoretic methods. Continuous-flow electrophoretic migration studies demonstrated under a variety of conditions that the platelet-damaging and the alpha-hemolytic activities migrated as a unit. Fractionation studies with the use of Sephadex G-100, carboxymethyl cellulose, and diethylaminoethyl cellulose failed to separate these two activities. Further, when alpha-toxin of demonstrated purity and crude toxin were adjusted to the same hemolytic activity, they possessed the same platelet-damaging activity. In addition, heat-reactivation studies with crude alpha-toxin revealed that the platelet-damaging effect was inactivated and reactivated in parallel with alpha-hemolytic activity. Comparable studies with purified alpha-toxin showed parallel inactivation of both activities at 60 C. Additional heating at 100 C failed to reactivate either activity. Electron micrographs revealed that purified alpha-toxin produced distinct degenerative changes in rabbit platelets. These studies also provided definite evidence that purified alpha-toxin has a damaging effect on human platelets. Monovalent alpha-antisera prevented platelet damage.
Union Heartland: The Midwestern Home Front during the Civil War

Review of: "Union Heartland: The Midwestern Home Front during the Civil War" by Donald C. Elder III.
Relationships of the female urethra and bladder in urinary stress incontinence.

Abstract Urinary stress incontinence in women is a problem without precise definition. Clinical evidence suggests that alterations in the relationship of the urethra and bladder play an important role in female stress incontinence. This report is to present results of a modified urethrocystographic technique which permits radiographic demonstration of the bladder outline and the entire undistorted urethra. Instead of a semirigid catheter, a metallic bead chain, of the type commonly used for carrying keys, was used to study urethral configuration. The method has the advantages of simplicity, accuracy of detail, freedom from distortion, and excellent roentgenographic contrast in both the anteroposterior and lateral positions.
Abstract 760: Suppression of ABCG2 mediated MDRin vitroandin vivoby a novel inhibitor of ABCG2 transport

Cancer is a disease whose treatment is often limited due to the development of a phenomenon known as multidrug resistance (MDR) that is its Achilles’ heel. Hence there is an immense demand for development of novel agents that can overcome the emergence of multidrug resistance (MDR) in cancer. A group of transmembrane proteins called ABC (ATP- binding cassette) transporters, present ubiquitously in the human body possesses a modular architecture, contributing immensely towards the development of MDR in various tumor types. An analysis of structural congeners among a group of compounds led to the discovery of CCTA-1523 that could selectively reverse ABCG2-mediated MDR in cancer cells both in vitro and in vivo. CCTA-1523 at concentrations upto 5 μM sensitized the cancer cells as well as transfected cells overexpressing ABCG2 to the substrate chemotherapeutic drugs. The reversal ability of CCTA-1523 was primarily due to the inhibition of the active efflux function of the transporter; also there was no change in the protein expression of the ABCG2 transporter in the presence of CCTA-1523 at reversing concentrations. Importantly the reversal effect produced by CCTA-1523 was reversible. Co-administration of CCTA-1523 restored the in vivo antitumor activity of doxorubicin in ABCG2 overexpressing tumor xenografts without added toxicity. Taken together, our findings indicate that CCTA-1523 is a potent and reversible, modulator of ABCG2 export function that may offer therapeutic promise for multidrug- resistant malignancies. Citation Format: Atish S. Patel. Suppression of ABCG2 mediated MDR in vitro and in vivo by a novel inhibitor of ABCG2 transport. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 760. doi:10.1158/1538-7445.AM2014-760
Oncogenic Transformation of Hamster Embryo Cells After Exposure to Inactivated Herpes Simplex Virus Type 1

The in vitro transformation of hamster embryo fibroblasts by herpes simplex virus type 1 (HSV-1) after exposure of the virus to UV irradiation is described. Cell transformation was induced by 2 out of 12 strains of HSV-1 that were tested for transforming potential. Cells transformed by the KOS strain of HSV-1 were not oncogenic when injected into newborn Syrian hamsters. However, cells transformed by HSV-1 strain 14-012 induced tumors in 47% of the newborn hamsters injected. HSV-specific antigens were found in the cytoplasm of cells transformed by both virus strains. Sera from tumor-bearing hamsters contained HSV-1- and HSV-2-neutralizing antibodies as well as antibodies which reacted specifically with HSV antigens by the indirect immunofluorescence technique. Hamster oncornavirus antigens were not detected by immunofluorescence methods. These observations represent the first evidence of the oncogenic potential of HSV-1.
Cyanobacterial photo-driven mixotrophic metabolism and its advantages for biosynthesis

Cyanobacterium offers a promising chassis for phototrophic production of renewable chemicals. Although engineered cyanobacteria can achieve similar product carbon yields as heterotrophic microbial hosts, their production rate and titer under photoautotrophic conditions are 10 to 100 folds lower than those in fast growing E. coli. Cyanobacterial factories face three indomitable bottlenecks. First, photosynthesis has limited ATP and NADPH generation rates. Second, CO2 fixation by ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) has poor efficiency. Third, CO2 mass transfer and light supply are deficient within large photobioreactors. On the other hand, cyanobacteria may employ organic substrates to promote phototrophic cell growth, N2 fixation, and metabolite synthesis. The photo-fermentations show enhanced photosynthesis, while CO2 loss from organic substrate degradation can be reused by the Calvin cycle. In addition, the plasticity of cyanobacterial pathways (e.g., oxidative pentose phosphate pathway and the TCA cycle) has been recently revealed to facilitate the catabolism. The use of cyanobacteria as “green E. coli” could be a promising route to develop robust photobiorefineries. Open image in new window
Neuroendocrine tumors of the lung: an update.

Abstract Context.—The 2004 World Health Organization (WHO) classification recognizes 4 major types of lung neuroendocrine tumors: typical carcinoid, atypical carcinoid, small cell lung cancer, and large cell neuroendocrine carcinoma. Markedly different prognostic implications and treatment paradigms for these tumors underscore the importance of accurate pathologic diagnosis. Objective.—To detail the clinical and pathologic features of lung neuroendocrine tumors, with emphasis on diagnostic criteria, differential diagnoses, and application of immunohistochemistry. The emerging evidence for the utility of Ki-67 (MIB1) in the diagnosis of lung neuroendocrine tumors, particularly in small biopsy and cytology, is emphasized. Data Sources.—The 2004 WHO classification, other published literature, and primary material from the author's institution. Conclusions.—The current WHO classification of neuroendocrine tumors is based on morphologic features in combination with precisely defined mitotic rate and absence or...
Biomechanical Response of Human Liver and Spleen Parenchyma in Uniaxial Unconfined Compression

Motor vehicle collisions (MVCs) commonly result in serious blunt abdominal injuries [1]. Although abdominal injuries account for only 3–5% of all injuries observed in MVCs, they comprise 8% of AIS 3+ injuries, 16.5% of AIS 4+ injuries and 20.5% of AIS 5+ injuries [24]. Currently, no crash test dummies used to assess injury risk in MVCs are equipped to represent individual solid abdominal organs located asymmetrically in the human abdomen. Consequently, researchers and safety engineers rely on finite element models (FEMs) to assess the risk of automotive related abdominal injuries. However, the response of these models must be locally and globally validated based on appropriate biomechanical data in order to accurately assess injury risk. There have only been a few studies which have investigated the compressive material properties of liver or spleen by performing compression tests on isolated samples [5–8]. Although these studies have provided considerable insight into the factors that affect the material response of the liver and spleen parenchyma, these studies have been limited to testing of animal tissue, sub-failure loading, or a single loading rate. Therefore, the purpose of this study was to quantify the compressive material properties of human liver and spleen parenchyma at various loading rates in order to characterize the viscoelastic and failure response.© 2012 ASME
Bacterial Leaf Spot of Cilantro in Florida.

In the 1995 to 1996 winter vegetable season, a leaf spot disease of cilantro (fresh coriander) (Coriandrum sativum L.) was widespread throughout commercial plantings in the Everglades Agricultural Area south and east of Lake Okeechobee. Symptoms first appeared as water-soaked spots ≤1 mm in diameter. These spots became dark brown to black and enlarged up to 2 mm in diameter. No chlorotic haloes developed around the lesions. The disorder was observed in numerous plantings of the cultivar Longstanding at four separate locations. Symptoms were apparent throughout each planting, with disease severity ranging from a few individual spots to numerous lesions covering nearly entire leaflets. Severe outbreaks were correlated with heavy precipitation events. In several instances, disease levels were great enough to render entire plantings totally unmarketable. A non-fluorescent bacterium was consistently isolated on King's medium B when a cooled inoculation needle was pushed through lesions. Six representative strains were chosen for further characterization. All strains were aerobic, gram-negative rods, and were oxidase and arginine dihydrolase negative. Levan was produced, but potato slices were not rotted. Tests for utilization of l-tartrate, l-lactate, and erythritol were negative. Biolog analysis identified all strains of the bacterium as Pseudomonas syringae. Highest similarity indices (0.52 to 0.81) were with P. syringae pv. pisi for four of the six strains. Suspensions of each strain were swab inoculated onto leaves of 4-week-old Longstanding cilantro seedlings in the greenhouse. Control plants were swabbed with sterile water only. Plants were covered with clear polyethylene bags for 72 h. Watersoaked spots were evident on test plants when bags were removed. Typical brown, greasy-looking leaf spots were seen by 6 days after inoculation. Control plants were symp-tomless. In a host-range study, cilantro and the following plants were mist-inoculated with a 107 CFU/ml suspension of each of the six test strains: carrot (Daucus carota L. 'Fancy Pack'), celery (Apium graveolens L. var. dulce (Mill.) Pers., 'June Belle'), garden pea (Pisum sativum L. 'Melting Sugar'), snap bean (Phaseolus vulgaris L. 'Pod Squad'), and onion (Allium cepa L. 'Evergreen Bunching'). Six days after inoculation, characteristic symptoms were evident on the cilantro. Four of the six strains produced a few (less than 10 per plant) bacterial leaf spot symptoms in carrot from which P. syringae was readily recovered. Some necrosis was observed on young, emerging leaves of snap bean. No symptoms were recorded for the other host species or the controls. This disease is similar to one reported on cilantro in California (1) and Germany (2). References: (1) D. A. Cooksey et al. Plant Dis. 75:101, 1991. (2) H. M. Toben and K. Rudolph. J. Phytopathol. 144:169, 1996.
Excitational, vibrational, and rotational temperatures in Nd:YAG and XeCl Laser-Induced plasmas

Abstract Laser-induced plasmas formed on graphite by a Nd:YAG laser at 1064 nm and by a XeCl laser at 308 nm were analyzed spectroscopically to determine vibrational, rotational, and excitation temperatures. For determination of vibrational and rotational temperature, the emission of the CN radical in the region between 385.1 and 388.3 nm was used to construct Boltzmann plots. Relative vibrational transition probabilities were calculated. For determination of excitation temperature, a small amount of lead or iron was added to the graphite target and Boltzmann plots were constructed using transition probabilities found in the literature.
Growth, Inequality and Poverty in Selected Caribbean and Latin American Countries, with Emphasis on Guyana

The statistical evidence surveyed suggests that as an indicator of development the Human Development Index is directly related to the level of per capita income; that inequality is countercyclical; and that economic growth is poverty reducing. In the case of Guyana the data suggest that nearly 43 per cent of the population were below the poverty line (approximately US$1 per day per person); that poverty is predominantly rural; that most of the poor seek employment in agriculture or in the informal (self employed) sector; and that there is a direct relationship between the level of education, health and poverty.
Optical second-harmonic generation as a surface probe for noncentrosymmetric media.

We show that optical second-harmonic generation can also be used as an effective surface probe with a submonolayer sensitivity for media without inversion symmetry. The adsorption of Sn on GaAs is used as an example. A detailed summary of all accessible elements of the surface nonlinear susceptibility tensor χ(2) for the various crystal faces of GaAs is provided.
Efficient detection of all pointer and array access errors

We present a pointer and array access checking technique that provides complete error coverage through a simple set of program transformations. Our technique, based on an extended safe pointer representation, has a number of novel aspects. Foremost, it is the first technique that detects all spatial and temporal access errors. Its use is not limited by the expressiveness of the language; that is, it can be applied successfully to compiled or interpreted languages with subscripted and mutable pointers, local references, and explicit and typeless dynamic storage management, e.g., C. Because it is a source level transformation, it is amenable to both compile- and run-time optimization. Finally, its performance, even without compile-time optimization, is quite good. We implemented a prototype translator for the C language and analyzed the checking overheads of six non-trivial, pointer intensive programs. Execution overheads range from 130% to 540%; with text and data size overheads typically below 100%.
Textural and microstructural gradient effects on the mechanical behavior of a tantalum plate

The effects of gradients in the texture and microstructure of a tantalum plate on mechanical behavior are examined. In particular, the effects of variations in grain size and texture from the surface of the plate to the centerline on the yield behavior and final shape of compression samples are investigated. Individual lattice orientations were measured on samples both before and after deformation using automatic analysis of electron backscatter diffraction patterns. These data were used as input to a polycrystal plasticity model based on the Taylor assumption of uniform strain. Results are compared from experimental and simulated compression tests. The effects of the texture and grain size gradients on these results are discussed. The influence of the texture gradient was found to be the dominating factor controlling the nonuniform plastic response of the material. This work also demonstrates the capability of currently available tools for characterizing inhomogeneous microstructures and modeling the effects of variations in texture and microstructure on mechanical behavior.
Witness competency in people with mental retardation: Implications for prosecution of sexual abuse

Victims with mental retardation have been excluded from the legal system based on the belief that they are incompetent to provide accurate, reliable testimony. Such restrictions contribute to the increased risk that people with mental retardation will be victimized. This article examines the complexity surrounding definitions of competency, as well as the mythology which serves to de-emphasize the abilities of victims to testify against an alleged perpetrator. The implications of the presumption of incompetency are highlighted through the example of sexual abuse. Empirical evidence and recent court cases are used to argue that people with mental retardation deserve access to the same standards of competency as the rest of the population.
Binaural interaction measured behaviorally and electrophysiologically in Young and old adults

12 young men (mean age = 39.1 years) and 12 older men (mean age = 69.4 years) presenting some degree of sensorineural hearing loss were chosen so that the two groups were audiometrically matched. Behavioral tests of binaural interaction (BI) included binaural fusion, rapidly alternating speech perception, and masking level difference (at 500 Hz). There was a tendency toward better performance by the younger subjects for each of these tests, but these comparisons fell short of statistical significance. Auditory brainstem responses (ABRs) and middle-latency responses (MLRs) to clicks were recorded in both monaural and binaural modes, with off-line derivation of BI components. Latencies of wave V (in ABR) and waves Pa and Nb (in MLR) were prolonged in the older subjects for all conditions; this effect was independent of degree of hearing loss. BI components did not differ substantially between the two groups, except for a 0.45-ms latency difference for the 'N1' peak, as expected from the raw ABR data. MLRs for both groups showed a pattern of BI which was different from that seen in young subjects with normal hearing, in that latency for wave Pa in MLR was not reduced in the binaural condition. The young subjects showed the expected reduction of binaural wave Pa amplitude compared to monaural sum responses, while the older subjects, as a group, did not. No significant correlations were found between behavioral and electrophysiological tests.
Effects of electric current on solid state phase transformations in metals

The influence of an electric current on the following solid state transformations in metals are considered: (1) intermetallic compound formation and growth in diffusion couples, (2) precipitation, (3) crystallization of amorphous alloys and (4) recrystallization and grain growth of cold worked metals. The formation and growth of intermetallic compounds were in qualitative accord with electromigration theory. Regarding precipitation, an electric current can either enhance or retard the precipitation rate, depending on the alloy, the current density and its frequency. Important factors appear to be the effect of current on the quenched-in vacancies and the presence of an internal stress. Both a continuous d.c. current and high current density electropulsing enhanced the crystallization rate of amorphous alloys. The effects are greater than can be explained by simple electromigration theory and suggest the cooperative motion of a larger number of atoms. Electropulsing enhanced the recrystallization rate of cold worked metals, but retarded subsequent grain growth. Enhancement of the recrystallization rate resulted mainly from an increase in the pre-exponential factor of the Arrhenius rate equation, which is considered to refer to the nucleation rate. Retardation of subsequent grain growth resulted from a lower residual dislocation density within the newly-formed grains.
Water, technology, and the courtroom: negotiating reclamation policy in territorial New Mexico

Abstract Historical investigation of arid landscapes and communities in the American West has long focused on the pivotal influence of federal reclamation policy, typically characterizing its implementation as the application of scientific and technological methods to a variety of water resource management issues. This paper departs from traditional views of reclamation by highlighting the highly variable and contingent ways in which new science-based forms of water management were proposed and negotiated in specific local places with particular cultural, legal, and historical geographies. Drawing theoretically from literature on the ‘geography of science,’ the paper probes the ways in which authority for a scientific approach to water management was created, negotiated, and expressed in local and regional contexts in the Territory of New Mexico, where authoritative systems of practical resource use and administration had been in long use before the U.S. government initiated its federal water reclamation program in 1902. Specifically, the paper examines two disputes entered and argued in front of northern New Mexico’s Rio Arriba District Dourt between 1903 and 1905. By departing from the geographical and scalar perspectives typically applied to environmental histories of the West and its reclamation landscapes, this ‘microgeographical’ approach promises a fresh perspective that emphasizes the highly contingent ways in which science-based water policy was implemented in multiple and complex environments.
The Effects of Thalamic Paraventricular Nucleus Lesions on Cocaine-Induced Locomotor Activity and Sensitization

The brain circuitry that subserves the augmented locomotor response to repeated psychostimulant administration has been the subject of intense scrutiny. The dopaminergic innervation of the nucleus accumbens is critically involved in psychostimulant-elicited behavioral sensitization, and recent studies suggest that lesions of structures that send glutamatergic projections to the nucleus accumbens alter the acquisition or expression of psychostimulant-elicited sensitization. Although certain thalamic nuclei provide a major glutamatergic input to the striatum, the involvement of the thalamus in psychostimulant-elicited sensitization has not been investigated. We therefore examined the effects of lesions of the thalamic paraventricular nucleus, which projects to the shell of the nucleus accumbens, on cocaine-elicited locomotor sensitization. Lesions of the paraventricular nucleus did not alter basal locomotor activity, but significantly enhanced the acute locomotor response to cocaine. In contrast, repeated cocaine administration did not progressively augment locomotor activity in lesioned rats, but did so in sham-lesioned animals. The thalamic lesions also blocked the conditioned locomotor response to the environment in which the cocaine injections took place. These data suggest that the thalamic paraventricular nucleus may be an integral part of extended circuitry that subserves both the conditioned and nonconditioned components of psychostimulant-induced behavioral sensitization.
Cell proliferation in the presence of telomerase.

Background Telomerase, which is active early in development and later in stem and germline cells, is also active in the majority of human cancers. One of the known functions of telomerase is to extend the ends of linear chromosomes, countering their gradual shortening at each cell division due to the end replication problem and postreplication processing. Telomerase concentration levels vary between different cell types as well as between different tumors. In addition variable telomerase concentrations will exist in different cells in the same tumor when telomerase inhibitors are used, because of limitations of drug delivery in tissue. Telomerase extends short telomeres more frequently than long telomeres and the relation between the extension frequency and the telomere length is nonlinear. Methodolgy/Principal Findings Here, the biological data of the nonlinear telomerase-telomere dynamics is incorporated in a mathematical theory to relate the proliferative potential of a cell to the telomerase concentration in that cell. The main result of the paper is that the proliferative capacity of a cell grows exponentially with the telomerase concentration. Conclusions/Significance The theory presented here suggests that long term telomerase inhibition in every cancer progenitor or cancer stem cell is needed for successful telomere targeted cancer treatment. This theory also can be used to plan and asses the results of clinical trials targeting telomerase.
Maintaining the vitamin A value of butter through winter feeding conditions.

Summary 1. Experiments have been conducted to determine the relative efficiency of various feeds in maintaining the high vitamin A value of summer produced butters. 2. Using samples of pasture produced butter of high vitamin A value as checks, it was found that under winter feeding conditions, timothy hay produced butter of low vitamin A value, while good quality alfalfa hay and soybean hay were very effective in either maintaining the high vitamin A level of butter or in restoring it to normal summer values. Thus it is possible to maintain a high vitamin A value of butter by practical feeding methods. 3. From the data presented in these experiments, it is evident that the vitamin A value of butter responds very rapidly to changes in the vitamin A value of the rations fed to the cows.
Conflict driven learning in a quantified Boolean satisfiability solver

Within the verification community, there has been a recent increase in interest in Quantified Boolean Formula evaluation (QBF) as many interesting sequential circuit verification problems can be formulated as QBF instances. A closely related research area to QBF is Boolean Satisfiability (SAT). Recent advances in SAT research have resulted in some very efficient SAT solvers. One of the critical techniques employed in these solvers is Conflict Driven Learning. In this paper, we adapt conflict driven learning for application in a QBF setting. We show that conflict driven learning can be regarded as a resolution process on the clauses. We prove that under certain conditions, tautology clauses obtained from resolution in QBF also obey the rules for implication and conflicts of regular (non-tautology) clauses; and therefore they can be treated as regular clauses and used in future search. We have implemented this idea in a new QBF solver called Quaffle and our initial experiments show that conflict driven learning can greatly speed up the solution process for most of the benchmarks we tested.
Infection following challenge of the lactating and dry udder of dairy cows with Actinomyces pyogenes and Peptostreptococcus indolicus

Challenge of 12 mammary glands of cows in mid-lactation with 10(7) colony forming units (cfu) of Peptostreptococcus indolicus on two occasions led to clinical mastitis in only four quarters. The bacteria were rarely recovered and disappeared from the secretion within 14 days. In challenges 7 days prior to drying off eight of 12 quarters became infected and at drying off all quarters challenged became infected. The infections established at drying off persisted well into the dry period. P. indolicus infection was also established in all of 12 dry glands challenged, but usually eliminated at calving or early in the next lactation. Isolation of P. indolicus was accompanied in about one-third of cases by changes in the appearance of the secretion. Intramammary challenge with Actinomyces (formally Corynebacterium) pyogenes led to clinical and subclinical infections in nine of 12 lactating glands and in all of six dry glands. Dry period infections with A. pyogenes were more severe and rarely eliminated even by antibiotic therapy. Infections during lactation were often eliminated either naturally or by antibiotic therapy. Intermittent recovery of A. pyogenes from the lactating mammary gland, without clinical signs of infection, was possible for up to 90 days after challenge. Combined infections with A. pyogenes and P. indolicus were clinically more severe with a higher frequency of systemic involvement. It was shown that in the non-lactating gland an acute mastitis, similar to 'summer mastitis' could be established either by simultaneous inoculation with A. pyogenes and P. indolicus or by subsequent inoculation of quarters excreting P. indolicus with A. pyogenes.
Impaired surface expression of PAF receptors on human neutrophils is dependent upon cell activation.

The capacity of human neutrophils to bind PAF was rapidly diminished upon cell stimulation with both physiological agonists (N-formylmethionylleucylphenylalanine (FMLP), leukotriene B4 (LTB4)) and pharmacologic agonists (phorbol 12-myristate 13-acetate (PMA), A23187). As a consequence, PAF responses in neutrophils were blunted, as monitored by an inhibition of intracellular Ca2+ mobilization. Downregulation of the PAF receptor in neutrophils by diverse agonists was temperature-sensitive and required intact cells. Scatchard analysis of binding data revealed that PAF binding sites were lost without an appreciable change in the affinity of the ligand for the receptor. The binding of the PAF receptor antagonist WEB2086 to neutrophils decreased in parallel with PAF binding. PMA-induced PAF receptor downregulation was staurosporine-sensitive while PAF receptor downregulation by A23187, FMLP, or LTB4 was staurosporine-resistant. Both neutrophil aggregation (a form of intercellular adhesion) and PAF receptor downregulation occurred only at high concentrations of agonists while other signaling processes such as the increase in [Ca2+]i, PKC activation, and PAF synthesis were stimulated at low concentrations of agonists. Furthermore, agonist-induced PAF receptor downregulation was observed only under conditions in which the activated neutrophils were stirred (or shaken) and were allowed to aggregate. Additionally, chelation of extracellular Ca2+ with EGTA minimized cell aggregation and also inhibited PAF receptor downregulation. While the nature of the biochemical signal or the physical changes in the plasma membrane associated with aggregation or that follow aggregation remain to be elucidated it is clear that full expression of cell activation (i.e., neutrophil aggregation) is required for PAF receptor downregulation.
Furan Approach to Vitamin D Analogues. Synthesis of the A-Ring of Calcitriol and 1α-Hydroxy-3-deoxyvitamin D3

The A-rings of calcitriol (1α,25-dihydroxyvitamin D(3)) and 1α-hydroxy-3-deoxyvitamin D(3) were synthesized using the furan approach. The critical steps in the synthesis of the A-ring of calcitriol involved an asymmetric carbonyl-ene reaction of 3-methylene-2,3-dihydrofuran with 3-(tert-butyldimethylsiloxy)propanal, a diastereoselective Friedel-Crafts hydroxyalkylation, an oxidation of the 2,3-disubstituted furan to give a γ-hydroxybutenolide, and a Peterson olefination. The A-ring (Z)-dienol of calcitriol was synthesized in 12 steps from 3-(tert-butyldimethylsiloxy)propanal in 17% yield.
Effects of withdrawal from chronic amphetamine administration on activity levels of albino rats.

18 albino rats were administered either saline or various dosages of d-amphetamine sulfate in activity wheel cages over a 13-wk. period. Food consumption was decreased under the 2.0, 4.0 and 8.0 mg/kg dosages, while water consumption was reduced only under the highest dose. Motor activity was elevated under 1.0 mg/kg and was depressed under 8.0 mg/kg, while no reliable effects were noted under the middle range of doses. Withdrawal from 1.0 and 2.0 mg/kg of amphetamine led to significant elevations in baseline activity. These changes in activity could not be readily explained in terms of a simple conditioning process. It was suggested that amphetamine may produce long lasting changes in the central nervous system which are reflected in elevated activity when the drug is withdrawn.
A Specific Region in the N Terminus of a Replication Initiation Protein of Plasmid RK2 Is Required for Recruitment of Pseudomonas aeruginosa DnaB Helicase to the Plasmid Origin

Broad host range plasmid RK2 encodes two versions of its essential replication initiation protein, TrfA, using in-frame translational starts spaced 97 amino acids apart. The smaller protein, TrfA-33, is sufficient for plasmid replication in many bacterial hosts. Efficient replication in Pseudomonas aeruginosa, however, specifically requires the larger TrfA-44 protein. With the aim of identifying sequences of TrfA-44 required for stable replication of RK2 in P. aeruginosa, specific deletions and a substitution mutant within the N terminus sequence unique to TrfA-44 were constructed, and the mutant proteins were tested for activity. Deletion mutants were targeted to three of the four predicted helical regions in the first 97 amino acids of TrfA-44. Deletion of TrfA-44 amino acids 21–32 yielded a mutant protein, TrfA-44Δ2, that had lost the ability to bind and load the DnaB helicase of P. aeruginosa or Pseudomonas putida onto the RK2 origin in vitro and did not support stable replication of an RK2 mini-replicon in P. aeruginosa in vivo. A substitution of amino acid 22 within this essential region resulted in a protein, TrfA-44E22A, with reduced activity in vitro, particularly with the P. putida helicase. Deletion of amino acids 37–55 (TrfA-44Δ3) slightly affected protein activity in vitro with the P. aeruginosa helicase and significantly with the P. putida helicase, whereas deletion of amino acids 71–88 (TrfA-44Δ4) had no effect on TrfA activity in vitro with either helicase. These results identify regions of the TrfA-44 protein that are required for recruitment of the Pseudomonas DnaB helicases in the initiation of RK2 replication.
Pareto efficiency, simple game stability, and social structure in finitely repeated games

Simple game (sensu Brown and Vincent, 1987) evolutionary theory, when coupled with social structure measured as non‐random encounter of strategy “clones”, often permits equilibrium refinement leading to Pareto superior outcomes (e.g., Axelrod, 1981; Myerson et al., 1991), a foundational goal of economic game theory (Myerson, 1991: 370–375). This conclusion, derived from analyses of one‐shot and infinitely repeated games, fails for finitely repeated games. While mutant cluster invasion enhances Pareto efficiency of equilibria in the former, it can depress Pareto efficiency in the latter. Cooperative equilibria of finitely repeated games (under economic analysis) can be susceptible to cluster‐invasion by even more Pareto efficient strategies which are not themselves evolutionarily stable. Evolutionary (simple) game theory's ability to eliminate Pareto inferior Nash equilibrium strategies induces vulnerabilities foreign to economic analysis. Simple game analysis of finitely repeated games suggests that socia...
Microtubule-kinetosome relationships in the motile cells of the blastocladiales.

Motile cells of four members of the fungal order Blastocladiales have been examined with respect to distribution of intracellular microtubules. In all cases, the cellular microtubules originate from a sleeve of electron opaque material which surrounds the proximal third of the kinetosome. The microtubules run forward in the zoospores, ensheathing the nucleus and the nuclear cap before terminating at the anterior ends of the cells. Each cell contains 27 microtubules which are arranged in 9 groups of 3 tubules each. The significance of these observations with respect to centers of organization for microtubules is discussed.
Antitumor agents LVI: The protein synthesis inhibition by genkwadaphnin and yuanhuacine of P‐388 lymphocytic leukemia cells

Two natural products isolated from the plant Daphne genkwa have been shown to possess antileukemic activity in mice. Genkwadaphnin and yuanhuacine were observed to inhibit DNA and protein synthesis in P-388 leukemic cells. A detailed study of the effects of these two diterpene esters on protein synthesis of leukemic cells was undertaken. The major effects of genkwadaphnin and yuanhuacine on protein synthesis were blockage of the elongation process and interference with the peptidyl transferase reaction. The latter reaction was suppressed at concentrations of the diterpene esters which were commensurate with concentrations that inhibited whole cell in vitro protein synthesis in P-388 cells.