cssi/SciSciGPT-SciSciNet huggingface dataset:
Selenium and nutrition of astragalus

Astragalus species were cultured on solutions of repurified nutrients in a greenhouse provided with carbon-filtered air. Earlier results of others which had demonstrated pronounced growth increases with selenium application are now considered to have been largely related to ameliorated toxicity of phosphate through suppressed sorption induced by selenium. Manganese sorption was similarly repressed. Losses of selenium, presumably organovolatiles, from cultures were confirmed; concomitant inadvertent accretions occurred. Essentiality of selenium for growth has not been conclusively established, but certain observations confirm the possibility. If selenium is required for growth of these species, the critical concentration will probably approximate one µg-atom Se/kg dry weight in leaves or whole plant tops.
PhasorToolBox – A Python Package for Synchrophasor Application Prototyping

Despite the rapid expansion of open source computer software applications, the development of synchrophasor applications has not kept pace. This paper presents a development package for quick prototyping of synchrophasor applications using Python programming language, specifically for the retrieval of data from any device that adopts the IEEE C37.118.2-2011 standard. The package provides a high-level interface for developers to quick prototyping for the rapid development of advanced synchrophasor applications. The asynchronous design pattern makes the packet robust to handle a high volume of I/O without compromising real-time performance.
Revisiting cognitive tools from a social and motivational perspective

The concept of computers as cognitive tools has been revisited to provide insight into the motivational and social dimension in light of the emerging technologies. Central to this concept are the two opposing philosophical views: learning from technology (amplification view of technology) versus learning with technology (constructivist view of technology). A literature review is provided on the paradigm shift in educational technologies from the “learning from paradigm” to the “learning with” paradigm. While the literature review shows powerful affordances of emerging technologies in engaging community of learners in knowledge construction and building, a critical analysis also indicates a significant gap in the traditional conception of cognitive tools, that is, a lack of research in the motivational and social dimension. Therefore, the purpose of this study was to investigate the motivational and social dimensions of cognitive tools in the context of emerging technologies, with the substantiation of empirical evidence from the literature.
A Drosophila Based Cancer Drug Discovery Framework

In recent years, there has been growing interest in using Drosophila for drug discovery as it provides a unique opportunity to screen small molecules against complex disease phenotypes in a whole animal setting. Furthermore, gene-compound interaction experiments that combine compound feeding with complex genetic manipulations enable exploration of compound mechanisms of response and resistance to an extent that is difficult to achieve in other experimental models. Here, I discuss how compound screening and testing approaches reported in Drosophila fit into the current cancer drug discovery pipeline. I then propose a framework for a Drosophila-based cancer drug discovery strategy which would allow the Drosophila research community to effectively leverage the power of Drosophila to identify candidate therapeutics and push our discoveries into the clinic.
Creating Supportive Contexts for Early Adolescents during the First Year of Middle School: Impact of a Developmentally Responsive Multi-Component Intervention

The transition to middle school is recognized as a period of increased risk for students' adjustment difficulties across the academic, behavioral, and social domains, underscoring the need for developmentally responsive interventions that address these potential vulnerabilities. This study examined the impact of a multi-component intervention on students' perceived adjustment during the first year of middle school using a cluster randomized controlled trial design. A total of 24 metropolitan schools (12 intervention), 220 teachers (122 intervention), and 2925 students (1537 intervention) participated. Teachers in intervention schools received training and consultation in the Behavioral, Academic, and Social Engagement (BASE) classroom management model. Significant intervention effects, moderated by students' gender, race/ethnicity, and economic status, were found for self-reported social anxiety, defiance, willingness to protect peers being bullied, and emotional problems. The results suggest that teachers trained in the BASE model were better able to create supportive classroom contexts during the middle school transition which promoted positive adjustment for particular students. This study stresses the importance of using developmentally appropriate strategies across correlated domains to reduce adjustment difficulties during the transition to middle school.
Growing and Improving from a Crisis

While a crisis can challenge the leader and the organization almost to a breaking point it is important to understand that crisis can also be an opportunity for growth. This chapter will discuss the ways leaders can improve their leadership abilities along with the culture of their organization during a crisis. It may seem counterintuitive, but crisis can be used by a leader to improve an organization. This chapter will also discuss how crisis is a part of our working life that we must accept.
Subjective criteria underlying noise-tolerance in the presence of speech.

The objective was to determine the relative contribution of four criteria (loudness, annoyance, distraction, speech interference) to participants’ noise-tolerance thresholds (NTT). While listening ...
Robotic Sleeve Gastrectomy

Introduction. The incidence of obesity has increased over the time. Nowadays, this condition has become a worldwide burden. Bariatric surgery has been developed as a long-term strategy for obesity treatment, reporting proof of efficacy in terms of weight loss and improvement of comorbidities.
Photoswitchable Serotonins for Optical Control of the 5-HT2A Receptor

The serotonin receptor family of G protein-coupled receptors (GPCRs) and ligand-gated ion channels play central roles in neuromodulation and are critical drug targets for the treatment of psychiatric disorders. Optical control of serotonin receptor subtypes has the potential to greatly enhance our understanding of the spatiotemporal dynamics of receptor function both at the cellular level and within neural circuits. While other neuromodulatory receptors have been successfully rendered photoswitchable, reversible photocontrol of serotonin receptors has not been achieved, representing a major gap in GPCR photopharmacology. Herein, by designing and screening a family of azobenzene-conjugated serotonin analogues, we developed the first photopharmacological tools that allow for such control. Azo5HT-2 shows light-dependent 5-HT2AR agonism, inducing receptor-mediated calcium signaling in the light-activated cis-form. Based on computational docking and test compound analysis, we also synthesize and test photoswitchable orthogonal, remotely-tethered ligands (PORTLs). BG-Azo5HTn PORTLs provide rapid, reversible and repeatable optical control following conjugation to SNAP-tagged 5-HT2AR. Overall, this study both introduces new tools for the optical control of 5-HT2ARs and provides a foundation for the broad extension of photopharmacology to the serotonin receptor family.
Protective effects of the synthetic flavonoid α-naphthoflavone against transcriptional and post-transcriptional changes induced by the carcinogen benzo[a]pyrene

3899 The exposure to polycyclic aromatic hydrocarbons (PAHs) has been regarded as a causative factor in the etiology of breast cancer. Acute exposure to PAHs are hallmarked by an induction of S-phase arrest. Flavonoids are a large family of dietary phenolic phytochemicals found in fruits and vegetables. Key features of flavonoids include the ability to compete with PAHs for binding to the aromatic hydrocarbon receptor (AhR) and suppress cell cycle progression. Therefore, dietary and synthetic flavonoids have been considered as chemotherapeutic agents against PAHs. 7,8-naphthoflavone (α-naphthoflavone:ANF) is a prototype synthetic flavonoid, which shares structural similarities with other natural flavonoids including genestein and quercitin. In this study, we examined in breast cancer MCF-7 cells the effects of ANF on B[a]P-induced changes in cDNA microarray profiles and protein levels of factors that contribute to DNA repair and cell cycle progression in S-phase. The treatment with B[a]P induced mRNA levels for members of the cytochrome P450 family (CYP1A1, CYP1B1, CYP2J2), cell cycle regulators (cdc25a, cdc25c), and DNA damage repair (ATM, BRCA1). In contrast, B[a]P down regulated transcript levels for various cyclins including A2, D1, and E1. The co-treatment with ANF tended to counteract the effects of B[a]P. Treatment with the B[a]P metabolite 7r,8r-dihydroxy-9t,10t-epoxy-7,8,9,10-tetrahydro-benzo[a]pyrene (BPDE) also triggered a reduction in mRNA levels for cyclins A2, D1 and E, but at lower doses and earlier time points. Changes in the cDNA microarray profiles of cyclins A2, D1, and E following exposure to B[a]P and BPDE were validated by RT-PCR. In contrast, western blot analysis indicated that B[a]P did not induce changes in expression of phosphorylated checkpoint kinase1 (Chk1-pSer345) and cyclins A2, D1 and E1. Conversely, B[a]P did induce p53, BRCA1, phosphorylated checkpoint kinase2 (Chk2-pThr68), while reducing CDC25a/CDC25c protein levels. The co-treatment of ANF restored the normal levels of these proteins. We conclude that the potential chemotherapeutic properties of dietary flavonoids may stem from their ability to modulate transcriptional and post-transcriptional changes induced by PAHs.
Chance fractures in the pediatric population

Object The pediatric Chance fracture (PCF) is an uncommon injury, but it has been increasingly reported. Knowledge is limited to few case reports and short series. To understand the various aspects of this injury, the authors reviewed the current literature. Methods A literature search was conducted using the PubMed and Ovid online databases and relevant key words. All articles that were in English and provided information regarding PCF as a sole or part of the objective were retrieved. Results Seventy-three articles were found to fulfill the inclusion criteria. Relevant information about PCF collected from these articles included: 1) mode of trauma, 2) associated injuries, 3) radiological classification, and 4) treatment. Conclusions Chance fractures in children are potentially devastating injuries largely caused by motor vehicle collisions, and these fractures may be more common than previously thought. Concomitant intraabdominal injuries are common and should be suspected, particularly when a seat belt...
Shifting the Focus

Agencies that serve survivors of sexual violence have frequently failed to make services accessible to lesbians and gay men. Similarly, agencies serving lesbians and gay men have frequently overlooked the problem of sexual violence in this community. One hundred fort-five lesbians, gay men and bisexuals responded to a survey about their knowledge of services for survivors of sexual violence, the services they need and want, their perceptions of sexual violence in the gay and lesbian community, and the extent of sexual victimization in the gay and lesbian community. Forty-one percent of respondents reported that they had been sexually victimized, and the majority believed that education programs were the most important service needed.
The vibrational spectra of diacetyl and diacetyl‐d6

The infrared and Raman spectra of diacetyl and diacetyl-d6 have been measured, and vibrational assignments are proposed for the fundamental bands and for several infrared active combination bands. The Raman spectrum of diacetyl-d6 has not hitherto been determined, and only a few of the stronger Raman bands of diacetyl have been reported in previous work. For both molecules a planar trans structure with C2h symmetry fits the experimental data; this confirms the conclusions of earlier investigators based on the analysis of the infrared and fluorescence spectra and on electron diffraction measurements.
Cloning and cell cycle-dependent expression of DNA replication gene dnaC from Caulobacter crescentus.

Abstract Chromosome replication in the asymmetrically dividing bacteria Caulobacter crescentus is discontinuous with the new, motile swarmer cell undergoing an obligatory presynthetic gap period (G1 period) of 60 min before the initiation of DNA synthesis and stalk formation. To examine the regulation of the cell division cycle at the molecular level, we have cloned the DNA chain elongation gene dnaC from a genomic DNA library constructed in cosmid vector pLAFR1-7. To ensure that the cloned sequence corresponded to dnaC, we isolated the gene by genetic complementation of the temperature-sensitive allele dnaC303 on DNA fragment that contained a Tn5 insertion element tightly linked by transduction to dnaC. The size of the dnaC gene was estimated to be 1,500 bp or less based on the pattern of complementation by subcloned restriction and BAL 31 deletion fragments. Nuclease S1 assays were used to map the transcription start site and to determine the pattern of dnaC expression in the cell cycle. Large amounts of the dnaC transcript began to accumulate only in the late G1 period of the swarmer cell and then peaked early during chromosome replication. We confirmed that the gene is periodically transcribed by monitoring the rate of beta-galactosidase synthesis directed by a dnaC promoter-lacZ fusion in a synchronous cell culture. dnaC is the first C. crescentus cell cycle gene whose regulation has been reported, and the discontinuous pattern of its expression suggests that the DNA synthetic period in these dimorphic bacteria is regulated in part by the stage-specific expression of DNA replication genes.
Objective Structured Assessments of Technical Skills (OSATS) Does Not Assess the Quality of the Surgical Result Effectively

Background Performance assessment in skills training is ideally based on objective, reliable, and clinically relevant indicators of success. The Objective Structured Assessment of Technical Skill (OSATS) is a reliable and valid tool that has been increasingly used in orthopaedic skills training. It uses a global rating approach to structure expert evaluation of technical skills with the experts working from a list of operative competencies that are each rated on a 5-point Likert scale anchored by behavioral descriptors. Given the observational nature of its scoring, the OSATS might not effectively assess the quality of surgical results.
An editorial introduction to the issue

On July 14-15, 1980, a National Invitational Conference on Planning for and Response to Acute Chemical Emergencies was held by the Disaster Research Center (DRC) at The Ohio State University. The six articles which follow are either extended versions of papers orally presented at the conference or elaborations of DRC findings introduced during the course of the meeting. Thus, this special issue can be seen as a product of this conference and, in one sense, serves as the proceedings of the meeting. Chemicals provide considerable benefit to society but do pose some risk for the human race. Our modem lifestyle, including much of our food, clothing, and housing, would be impossible without the chemical innovations of recent times The contributions which chemicals have made to our high standard of living, especially in urbanized and industrialized societies, seems incontestable. Yet, the production, distribution, and usage of certain chemicals also create varying degrees of risk to life, property, and well-being. Some risks are of a chronic or long-term nature as witnessed in the Love Canal situation and other chemical dump areas. Still other threats of a chemical nature tend to be more acute or sudden, creating emergencies which have to be prepared for or responded to when they occur. The conference focused on questions and issues related to such emergencies. It particularly dealt with the situation at the local community level, at least as manifested in American society. Two general questions were especially addressed: in what ways are local communities prepared for acute chemical emergencies, and how do local communities respond to such emergencies? Given these interests, the first paper by Fawcett attempts to put the problem of acute chemical hazards in a historical perspective. In very general terms, it notes that the problem has changed from obvious situations of fire and explosion of relatively short duration to ones in which threats may manifest themselves in many ways. However, it is noted that the danger is not intrinsic in chemicals, themselves, but in the ways in which they are handled.
Application of the hoch-arpshofen model to the liquid iron-carbon and iron-silicon systems

Abstract The complex model developed by Hoch and Arpshofen is used to describe the thermodynamic behavior of the liquid iron-carbon and iron-silicon systems; the standard states are the pure liquids. We have ΔGexm = n(x − xn)W where n is the size of the complex (number of atoms), W is the interaction parameter, and x is the atom fraction of the component with the lower binding capacity. The data used were taken from the compilation of Hultgren, and the phase diagrams from Hansen. In both systems, x is the atom fraction of Fe, and n = 3. The data used in the Fe-C system were gDG exC, ΔG exFe at 1873 K, the eutectic composition at 1426 K, and the carbon liquidus from 1426 K to 3148 K. In this system W = −(2.336 ± 0.033) + (0.6374 ± 0.020)T in kK. For the Fe-Si system, ΔG exSi at 1873 K, ΔH m, and ΔH exSi were used, and from the phase diagram four points: three points FeSi(s) in equilibrium with liquid, and Si(s) in equilibrium with liquid. In the Fe-Si system W = −(4.014 ± 0.144) + (.7758 ± 0756)T in kK.
Generation of low-toxicity interleukin-2 fusion proteins devoid of vasopermeability activity

Because of its key role in immunity, interleukin-2 (IL-2) has been studied extensively for the adoptive immunotherapy of cancer. Although systemic administration of IL-2 has been shown to stimulate antitumor responses in vivo, its efficacy in the clinic has been limited by the development of serious side effects, including the induction of vascular leak syndrome. Previously, we have identified a small peptide fragment of IL-2 that was found to contain the entire vasopermeability activity of the cytokine. The identification of the location of this potentially undesirable property of IL-2 enabled us to focus on the generation of mutant derivatives that might be lacking vasopermeability activity but that retain cytokine functionality. In addition to this discovery, our laboratory has constructed monoclonal antibody/IL-2 fusion proteins that can target this potent cytokine directly to tumor for the immunotherapy of both solid and lymphoid malignancies. Using this fusion protein technology, we have constructed a series of point mutations in the newly identified vasopermeability region of IL-2 for the purpose of deleting this activity. Fusion proteins showing reduced or deleted vasopermeability activity were then tested for their cytokine potency by several methods, including their binding to IL-2 receptors, T-cell proliferation assays, the induction of secondary cytokines, dose-escalating toxicity, and finally their ability to treat established solid tumors in syngeneic immunocompetent mice. The results of these studies clearly show that the vasopermeability activity of IL-2 can be substantially deleted by single point mutations such as Arg38Trp without grossly affecting the immune function of the cytokine.
Multiresolution registration of remote sensing images using stochastic gradient

In image registration, we determine the most accurate match between two images, which may have been taken at the same or different times by different or identical sensors. In the past, correlation and mutual information have been used as similarity measures for determining the best match for remote sensing images. Mutual information or relative entropy is a concept from information theory that measures the statistical dependence between two random variables, or equivalently it measures the amount of information that one variable contains about another. This concept has been successfully applied to automatically register remote sensing images based on the assumption that the mutual information of the image intensity pairs is maximized when the images are geometrically aligned. The transformation which maximizes a given similarity measure has been previously determined using exhaustive search, but this has been found to be inefficient and computationally expensive. In this paper we utilize a new simple, yet powerful technique based on stochastic gradient, for the maximization of both similarity measures with remote-sensing images, and we compare its performance to that of the exhaustive search. We initially consider images, which are misaligned by a rotation and/or translation only, and we compare the accuracy and efficiency of a registration scheme based on optimization for this data. In addition, the effect of wavelet pre-processing on the efficiency of a multi- resolution registration scheme is determined, using Daubechies wavelets. Finally we evaluate this optimization scheme for the registration of satellite images obtained at different times, and from different sensors. It is noted that once a correct optimization result is obtained at one of the coarser levels in the multi-resolution scheme, then the registration process is much faster in achieving subpixel accuracy, and is more robust when compared to a single level optimization. Mutual information was generally found to optimize in about one third the time required by correlation.© (2002) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Physicochemical features of hemoglobin of the crustacean, Triops longicaudatus.

Abstract Hemoglobin from the notostracan, Triops longicaudatus , was purified and characterized physicochemically. Stoke's radius (77.7 A) and the sedimentation coefficient ( S 20,w = 17.1) were estimated by gel filtration chromatography and density gradient centrifugation, respectively and then used to calculate the molecular weight (600,400 daltons), the frictional ratio (1.33), and the diffusion coefficient (2.70). These physical parameters, along with data on the amino acid composition, are compared with similar data on other crustacean hemoglobins.
Bezoars—A complication of the postgastrectomy state

Bezoars have not been readily recognized as a postgastrectomy complication. A review of the literature and this report of 2 cases stress the importance of this phenomenon. Roughage, delayed emptying, narrow stoma, and decreased gastric secretions, as well as improper mastication and inadequate teeth, play a role in producing bezoars. Prevention, with emphasis on the avoidance of foods with high fiber content and on good oral hygiene, is the preferred measure. However, a short trial of papain and surgery are indicated once the bezoar has formed.
Gastric varices presenting as "pseudotumors" of the cardia.

Two cases of gastric varices presenting as pseudotumors of the cardia are reported. The diagnosis should be entertained when a submucosal nodular “mass” is encountered in the cardia. Suspicion rises in the presence of a history of hepatic or extrahepatic disease leading to portal or splenic vein obstruction. A history of hematemesis may serve to confirm the diagnosis and has occurred with remarkable frequency in many of the reported cases. The presence of esophageal varices and splenomegaly is of further aid in making the diagnosis. At this point if the diagnosis is still in doubt, a more definite study can be obtained with splenoportography.
An attenuated mutant of Venezuelan encephalitis virus: biochemical alterations and their genetic association with attenuation.

Abstract A temperature-sensitive mutant of Venezuelan encephalitis virus derived by chemical mutagenesis from the hamster-virulent 68U201 wild-type ( wt ) strain was previously found to be attenuated. This mutant, is 126, replicated in infected hamsters and elicited production of protective antibodies. Further phenotypic differences between is 126 and 68U201 wt have been characterized in an attempt to localize the genetic basis of the mutant's attenuated virulence. The mutant was shown to differ from the parent virus with respect to virion surface structure-dependent characteristics: temperature lability, plaque sizes in Vero cells, and binding properties to hydroxylapatite. The surface difference was identified by isoelectric focusing of the virion envelope glycoproteins as an alteration in the E 1 glycoprotein. The common genetic basis of all these phenotypic differences was demonstrated by the isolation of independently arising, stable genetic revertants of ts 126, which exhibited characteristics identical in every respect to 68U201 wt . It appears from these studies that the mutation which gave rise to the is 126 mutant virus occurred in the structural gene coding for the E 1 envelope glycoprotein and that the resultant phenotypic alteration in this glycoprotein is genetically associated with the mutant's lack of virulence.
Surface heterogeneity and diffusion in the desorption of methanol from WO3(001) surfaces

We have investigated the role of intermolecular interactions, surface site heterogeneity, and surface diffusion on the desorption of methanol from the oxidized and reduced surfaces of (001) oriented, epitaxially grown WO3 films on Al2O3(1102) substrates. Ultraviolet photoelectron spectroscopy (UPS) showed that methanol adsorbed molecularly on the oxidized WO3 surface but dissociatively on the reduced surface. On both surfaces, calibrated thermal desorption spectroscopy (CTDS) showed the desorption of methanol as an asymmetric peak that shifts to lower temperature with increasing coverage, behavior that is typical of water and alcohols on other oxide surfaces. X-ray photoelectron spectroscopy (XPS) was used to characterize the surface by monitoring the W4f and valence-band region; STM studies indicate that the surface is heavily stepped. Monte Carlo simulations including surface heterogeneity and rapid diffusion effects are consistent with the observed desorption spectra.
Phase II trial of dacarbazine, mitomycin, doxorubicin, and cisplatin with sargramostim in uterine leiomyosarcoma: a Gynecologic Oncology Group study.

Abstract Objective. Following a reported 23% response rate (RR) for mitomycin (M), doxorubicin (A), and cisplatin (P) and preliminary data suggesting a superior RR for dacarbazine (D) + MAP + sargramostim, the Gynecologic Oncology Group (GOG) conducted a phase II trial of DMAP + sargramostim in patients with advanced uterine leiomyosarcoma. Methods. Eligibility required measurable disease, a GOG performance score of 0–2, and recovery from surgery/radiotherapy. Treatment consisted of sargramostim 250 μg/m 2 SC q 12 h days −6 through −3, followed by D 750 mg/m 2 IV over 2 h, M 6 mg/m 2 IV, A 40 mg/m 2 IV and P 60 mg/m 2 IV over 2 h on day 1, followed by sargramostim 250 μg/m 2 SC days 2–15. Cycles were repeated q 28 days (if ANC ≥ 1500/μl and platelets ≥ 100,000/μl) until disease progression or toxicity prevented further therapy. Doses were to be reduced by 20% for grade 4 neutropenia >7 days or any grade 4 thrombocytopenia and by 10% for a 1- to 2-week treatment delay for myelosuppression. Results. One of 19 patients who entered the study was ineligible. Eighteen patients received a median of 3.5 cycles (range: 1–6 cycles) of therapy. The overall RR was 27.8% (5.6% complete and 22.2% partial responses). Percent of patients with grade 3 or 4 toxicities included 78% neutropenia, 94% thrombocytopenia, 61% anemia, 44% GI, 28% infection, and 17% azotemia. Conclusions. DMAP + sargramostim produced a 27.8% RR, but its complexity and toxicity precluded further investigation, and the study was closed after the first stage of accrual.
Partitioning of ρ-tocopherol in aqueous mixtures of TAG and isolated muscle membranes

To study the uptake of ρ-tocopherol by aqueous suspensions of membranes isolated from chicken muscle and the partitioning of the antioxidant in mixtures of chicken TAG and membranes, ρ-tocopherol was added to suspensions of these components and they were centrifuged. In an aqueous suspension of membranes only, the tocopherol uptake increased linearly with tocopherol concentration, at about 50% of the added ρ-tocopherol at all concentrations. The incorporation of tocopherol into the membranes was independent of incubation temperature in the range of 0–37°C. Studies with aqueous mixtures of membranes and TAG suggested a very low exchange of tocopherol between the different lipid fractions upon mixing when the tocopherol resided initially in one lipid fraction. Adding ρ-tocopherol in ethanol favored incorporation of the antioxidant into the membranes; little antioxidant was incorporated into the membranes when it was added to the suspensions in oil. The results suggest that partitioning of exogenous ρ-tocopherol between TAG and membrane lipids in muscle foods may be controlled in part by proper selection of the solvent in which it is added.
Binding of cytotoxic T-lymphocytes to supported lipid monolayers containing trypsinized H-2Kk

H-2Kk, a transmembrane protein coded for by the mouse major histocompatibility complex, was modified by trypsinization to remove its intracellular segment and was incorporated into lipid monolayers made on an alkylated glass substrate. Cloned cytotoxic T-lymphocytes specific for H-2Kk were incubated on the monolayer. More cytotoxic T-cells bound to monolayers containing the H-2Kk fragment (tH-2Kk) than to control monolayers made without H-2Kk. Preincubation of monolayers with alloantisera against H-2Kk reduced binding of CTL to levels seen with control monolayers. This method offers the possibility of studying specific binding of cytotoxic T-cells to well-defined model membranes.
The right to habilitation: What does it mean?

Abstract Over the past decade some of the major conceptual and empirical issues confronting the field of mental retardation have been put on center in various civil class action law suits. One of the most widely known is the case of Wyatt vs. Stickney in which the Court asserted the constitutionally protected right of mentally retarded residents of public facilities to receive habilitation. In order to ensure this right the Court established various standard, many of which bear upon professional pratice, research, and empirical knowledge. In this article an effort is made to highlight some of the complexities that arise when the law intrudes upon professional practice and theory, particularly with respect to habilitation. Attention is also directed to the process by which public policy is formed and the role of behavioral research in that process.
Stability and electronic properties of atomistically-engineered 2D boron sheets

First principles calculations based on generalized-gradient approximation to density functional theory are performed to study structural and electronic properties of the 2D sheets consisting of the elemental boron. The results find that the boron sheet can be stable and can possess metallic or semiconducting character depending on its atomistic configuration. The unique features present in the electronic properties of the buckled {1212} and reconstructed {1221} sheets would lead to a significant variation on electronic and mechanical properties of the corresponding single-walled boron nanotubes.
The Intraseasonal Oscillation in Eastern Pacific Sea Levels: How Is It Forced?

Abstract Daily sea level and surface winds at eastern Pacific shore locations and equatorial islands, together with gridded five-day averages of 850 mb winds, have been analyzed for the 1979–84 period to determine how the 40–60 day intraseasonal oscillation of eastern Pacific sea levels is forced, as described by Spillane et al. for 1971–75. The oscillation was also present in 1980–84 from Callao, Peru, to San Francisco, with maximum energy near 52–57 days and band limits of 43 and 65 days. During 1980–84 there was no evidence for forcing of the large-scale oscillation in the eastern Pacific, although a local contribution of forcing was superimposed on the remote signal at the California stations. Interannual fluctuations in amplitude were evident in the sea level time series, consistent with those of the corresponding wind oscillation in the western equatorial Pacific. The oscillation was best developed in both variables in 1980–82 and became weak or nonexistent during the recovery phase of the 1982–83 E...
How Now Brown Cow: Phoneme Awareness Activities for Collaborative Classrooms:

Research indicates a strong relationship between early phoneme awareness and later reading success, and it links some reading failure to insufficiently developed phoneme awareness skills. Intervent...
Post-Circuit Blues: Motivations and Consequences of Crystal Meth Use Among Gay Men in Miami

Miami, Florida was at the vanguard of the rise of circuit parties and attendant club drug use—especially ecstasy, GHB, and ketamine—in the 1990s. Crystal methamphetamine, a drug of abuse among gay men for some years on the West coast, gradually moved east toward the end of the decade and recently became prevalent in Miami. This paper reports the results of focus group research into the motivations and consequences of crystal use among gay men in this new setting. Loneliness, fears about physical attractiveness due to aging and illness, and desires to lose sexual inhibitions were common motivations for using the drug. Continued use of crystal was often described as the cause of lost friendships, employment and long-term relationships, as well as sexual behaviors that put men at risk for HIV and other sexually transmitted infections. Implications for drug and sexual risk prevention interventions are discussed.
In vitro induction of stigma-like and style-like structures from receptacle tissue in Nicotiana tabacum L.

Stigma-like and style-like structures were induced from the receptacle tissue in tobacco (Nicotiana tabacum L.). The presence of kinetin was necessary to induce these structures. The structures have a form similar to and the same function as normal stigmas and styles.
COMPARISON OF MONOLITHIC PASSIVELY MODE-LOCKED LASERS USING In(Ga)As QUANTUM DOT OR QUANTUM WELL MATERIALS GROWN ON GaAs SUBSTRATES

In this paper, a technology comparison between monolithic passively mode-locked lasers (MLLs) fabricated from 1.24 μm InAs dots-in-a-Well (DWELL) and 1.25 μm InGaAs single quantum well (SQW) structures grown using elemental source molecular beam epitaxy (MBE) is presented. 5 GHz optical pulses with sub-picosecond RMS jitter, high pulse peak power (1W) and narrow pulse width (< 10 ps) are typical of these monolithic two-section InAs DWELL passive MLLs. An InGaAs single quantum well MLL with the 42% indium is shown to exhibit a superior high-temperature performance. Compared with the typical operating range of the InAs DWELL devices (<60°C), the operation is in excess of 100 °C and is particularly attractive for clocking applications in next generation microprocessors. Based on an 8-band k.p analysis the reduction in the band edge density of states for such a quantum well is discussed.
Effects Of Polyamines On Vibrio Cholerae Virulence Properties

Vibrio cholerae is the causative agent of the severe enteric disease cholera. To cause cholera the bacterium must be able to synthesize both cholera toxin (CT) and toxin-coregulated pilus (TCP) which mediates autoagglutination and is required for colonization of the small intestine. Only a few environmental signals have been shown to regulate V. cholerae virulence gene expression. Polyamines, which are ubiquitous in nature, and have been implicated in regulating virulence gene expression in other bacteria, have not been extensively studied for their effect on V. cholerae virulence properties. The objective of this study was to test the effect of several polyamines that are abundant in the human intestine on V. cholerae virulence properties. All of the polyamines tested inhibited autoagglutination of V. cholerae O1 classical strain in a concentration dependent manner. Putrescine and cadaverine decreased the synthesis of the major pilin subunit, TcpA, spermidine increased its production, and spermine had no effect. Putrescine and spermidine led to a decrease and increase, respectively, on the relative abundance of TCP found on the cell surface. Spermine led to a small reduction in cholera toxin synthesis whereas none of the other polyamines had an effect. The polyamines did not affect pili bundling morphology, but caused a small reduction in CTXφ transduction, indicating that the TCP present on the cell surface may not be fully functional. We hypothesize the inhibition of autoagglutination is likely to be caused by the positively charged amine groups on the polyamines electrostatically disrupting the pili-pili interactions which mediate autoagglutination. Our results implicate that polyamines may have a protective function against colonization of the small intestine by V. cholerae.
On the Numerical Solution of Two-Dimensional Elasticity Problems

Abstract An iterative method is presented for solving plane strain and plane stress problems for homogeneous and isotropic elastic materials. Displacements or some combination of displacements and stresses are prescribed on the boundary of the elastic solid. The iterates are evaluated numerically by difference methods. The direct block factoring method is used to solve the resulting system of algebraic equations. Applications to specific problems are given. A proof of the convergence of the analytic iterations is given for problems where the displacements are specified on the entire boundary.
Hepatic 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase: phosphate dependence and effects of other oxyanions.

Abstract The effects of various oxyanions on the activities of rat liver 6-phosphofructo-2-kinase/ fructose-2,6-bisphosphatase (EC 2.7.1.105/3.1.3.46) were examined. No evidence could be found for an absolute dependence of the kinase activity on inorganic phosphate as was recently reported by M. Laloux, E. Van Schaftingen, and H.-G. Hers ((1985) Eur. J. Biochem.148, 155–159) . Rather, phosphate and arsenate activated the kinase by decreasing the enzyme's Km for fructose 6-phosphate without affecting its Km for ATP or Vmax. The Km of the kinase for fructose 6-phosphate in the presence of inorganic phosphate was found to be significantly lower (6 μ m ) than previously reported (30 μ m ) when the hydrolysis of fructose 2,6-bisphosphate by the concomitant bisphosphatase activity at low Fru 6-P concentrations was taken into account. The KA's for phosphate and arsenate activation of the kinase were 0.2 and 0.3 m m , respectively. A number of other oxyanions, including pyrophosphate, sulfate, tungstate, selenate, and molybdate all inhibited the kinase by increasing the Km for fructose 6-phosphate. The apparent Ki's for inhibition of the kinase were in the 0.5–1 m m range. In contrast, all of these oxyanions activated the bisphosphatase, with half-maximal effects requiring millimolar concentrations. Inorganic phosphate was the most potent activator with a KA of 1 m m . In contrast to the other oxyanions, vanadate and meta-periodate inhibited the kinase but had no effect on the bisphosphatase. Vanadate appeared to be a noncompetitive inhibitor since its effects were not overcome by Pi, ATP, or fructose 6-phosphate, and the species responsible was shown to be decavanadate. Like vanadate, meta-periodate had no effect on the bisphosphatase, though it was a potent inhibitor (I0.5 = 30 μM) of the kinase. Its effects were shown to be time-dependent and reversed by dithiothreitol, suggesting that it acted by an oxidative mechanism. These results augment the mounting body of evidence that the enzyme's two reactions are catalyzed at discrete active sites.
A regional scale modeling study of atmospheric transport and transformation of mercury. II. Simulation results for the northeast United States

Abstract This paper presents the results of a simulation study of the transport, transformation, and deposition of atmospheric mercury (Hg) in the northeastern United States for 5 consecutive days in summer 1997, using the newly developed regional scale air quality model described in part I. Hourly ambient concentrations, in-cloud transformations, and deposition fluxes were predicted for each of the three mercury species: Hg(0), Hg(II), and Hg(p). The simulation results showed that surface level Hg concentrations over the land varied diurnally with the boundary layer structure. The Hg concentrations over the coastal ocean water were strongly influenced by the concentrations over land because of atmospheric advection by the prevailing westerly winds in the region. Over 90% of the ambient air concentration of Hg was in the form of Hg(0) vapor. Approximately half of the total Hg in wet deposition originated from ambient Hg(0), while the predominant species in dry deposition was Hg(II). The simulation predicted more dry deposition ( 31 kg day −1 ) than wet deposition ( 18 kg day −1 ) over the region for the simulation period. The re-emission of Hg(0) from land and water surfaces ( 46 kg day −1 ) was of the same magnitude as the total anthropogenic emission ( 55 kg day −1 ) within the region. Both precipitating and non-precipitating clouds were shown to be important media for in-cloud transformation of Hg(0). It was predicted that transformation and redistribution caused a net gain of Hg(p) at the upper troposphere during rain events. Over the region of simulation, the amount of Hg(0) transformation in non-precipitating clouds was 30% higher than in precipitating clouds. In co-existing non-precipitating clouds, the amount of Hg(0) transformation in the lower and upper troposphere was approximately equal.
Tracheal replacement: a critical review

This review discusses the need for tracheal replacement, distinct from resection with primary anastomosis, the requirements for replacement, and the many efforts over the past century to accomplish this goal experimentally and clinically. Approaches have included use of foreign materials, nonviable tissue, autogenous tissue, tissue engineering, and transplantation. Biological problems in each category are noted.
Locomotive Wheel-Slip and Wheel-Lock Protection

ACCIDENTS HAVE OCCURRED within recent years caused by the locking of driving wheels on diesel-electric locomotives. High-speed wheel slip is one cause of locked axles. Hence it is desirable to have some means of protecting a locomotive against wheel slip, wheel lock, motor overspeed, and wheel slide during braking.
Secretion into the Cerebrospinal Fluid by Caudal Neurosecretory Neurons

Neurons of the regenerating caudal neurosecretory system of Tilapia mossambica and of the normal system of Albula vulpes send processes into the central canal of the spinal cord. Evidence for appreciable release of secretion into the cerebrospinal fluid from these processes has been obtainied with both light and electron microscopes.
Regulation of Gene Expression of a Binding Protein for Fibroblast Growth Factors by Retinoic Acid

Retinoids are potent regulators of growth and differentiation and have shown promise as chemotherapeutic agents against selected cancers in particular squamous cell carcinoma (SCC). Earlier studies from our laboratory showed that a secreted binding protein for fibroblast growth factors (BP) is expressed at high levels in SCC cell lines and tissue samples. Here we investigate whether retinoids affect BP gene expression in SCC. In six different human SCC cell lines, we found that all-trans-retinoic acid (tRA) down-regulated BP mRNA by 39-89% within 24 h. From this group of cell lines, we selected the ME-180 cell line for more detailed studies of the mechanisms of this regulation. tRA down-regulated BP mRNA in a time- and dose-dependent manner. The effect of tRA was reversible, and BP mRNA returned to control levels within 24 h after removal of tRA. We also measured BP mRNA half-life and performed nuclear run-on experiments to study if tRA down-regulates BP by destabilizing the mRNA and/or by decreasing the rate of transcription. BP mRNA in ME-180 cells is very stable with a half-life of >16 h, and tRA decreased BP mRNA with a half-time of 5 h. Actinomycin D and cycloheximide blocked the tRA effect, suggesting that transcriptional regulation as well as de novo protein synthesis contribute to this post-transcriptional regulation of BP mRNA levels. In addition, tRA decreased the rate of BP gene transcription by 2- to 3-fold within 1 h. We conclude that retinoids down-regulate BP gene expression by post-transcriptional as well as by transcriptional mechanisms.
Searching for modifications to the exponential radioactive decay law with the Cassini spacecraft

Abstract Data from the power output of the radioisotope thermoelectric generators aboard the Cassini spacecraft are used to test the conjecture that small deviations observed in terrestrial measurements of the exponential radioactive decay law are correlated with the Earth–Sun distance. No significant deviations from exponential decay are observed over a range of 0.7–1.6 A.U. A 90% CL upper limit of 0.84 × 10 - 4 is set on a term in the decay rate of 238 Pu proportional to 1 / R 2 and 0.99 × 10 - 4 for a term proportional to 1 / R . The terrestrially measured Earth–Sun distance correlation is ∼ ( 3 × 10 - 2 ) / R 2 .
The state of qualitative tourism research

Abstract Previous reviews of tourism research methods have concentrated on studies underpinned by positivist science or assessments of quantitative methods and analyses. Conspicuous by their absence are reviews that focus on studies supported by the interpretive paradigm and assessments of qualitative analyses. This paper provides a descriptive review of the latter research using feature articles from four major journals in the field, employing “moments of qualitative research” as the framework of analysis. This paper makes no attempt to assess methodological sophistication but provides baseline data about previous and present uses of the interpretive paradigm and qualitative methods. It reviews each journal from its inception through 1996.