cssi/SciSciGPT-SciSciNet huggingface dataset:
Performance analysis of broadcast in multi-channel multi-radio wireless mesh networks

Broadcast is a fundamental operation for wireless mesh networks. It plays an important role in the communication protocol design. Many existing work have studied the NP-hard broadcast problem in multi-hop networks. However, most of them assume a single-channel and single-radio wireless network model. We investigate broadcast in multi-channel multi-radio wireless mesh networks. In multi-channel multi-radio wireless mesh networks, the wireless interference due to simultaneous transmissions from the same channel and intra-node interference render the broadcast problem nontrivial. In this work, we analyze the performance of a broadcast protocol with MAC-layer scheduling under different networking conditions. We also explore the performance improvement by incoporating the neighbor elimination scheme with the broadcast protocol. We analyze the performance improvement of the integrated protocol in environments of multi-channel multi-radio and multi-rate.
Simulating the Case against Stock Picking

In simulating a portfolio of 100 security prices the median terminal price was regularly below that of the average mean portfolio price. In that picking a single security would likely choose the median terminal price, a case can be made against stock picking.
Effect of distant encounters on black hole binaries in globular clusters: Systematic increase of in-cluster mergers in the LISA band

In this paper we study how distant weak interactions impact the dynamical evolution of merging binary black holes (BBHs) in dense stellar clusters. Recent studies have shown that BBHs undergoing strong interactions in dense clusters are likely to significantly contribute to the rate of observable gravitational wave (GWs) mergers, and that many of these will have measurable eccentricities in the LISA and LIGO detectors. However, what not yet have been quantified is the effect from the many more distant weak interactions the BBHs undergo in between their strong interactions. Weak interactions change the eccentricity of the BBHs, and can will therefore impact both their GW inspiral time and merger probability. We here use a simple cluster model to explore how BBHs are driven to merger under the influence of both weak- and strong interactions, as well as a GW emission. We find that including weak interactions leads to a notable increase in the number of BBHs that merge inside their cluster, which correspondingly leads to a higher number of eccentric LISA sources. These preliminary results illustrate the importance of including weak interactions for accurately modeling how BBHs merge in clusters, and how to link their emitted GW signals to their astrophysical environment.
Shifts in plant functional composition following long‐term drought in grasslands

Plant traits can provide unique insights into plant performance at the community scale. Functional composition, defined by both functional diversity and community‐weighted trait means (CWMs), can affect the stability of above‐ground net primary production (ANPP) in response to climate extremes. Further complexity arises, however, when functional composition itself responds to environmental change. The duration of climate extremes, such as drought, is expected to increase with rising global temperatures; thus, understanding the impacts of long‐term drought on functional composition and the corresponding effect that has on ecosystem function could improve predictions of ecosystem sensitivity to climate change. We experimentally reduced growing season precipitation by 66% across six temperate grasslands for 4 years and measured changes in three indices of functional diversity (functional dispersion, richness and evenness), community‐weighted trait means and phylogenetic diversity (PD). Specific leaf area (SLA), leaf nitrogen content (LNC) and (at most sites) leaf turgor loss point (πTLP) were measured for species cumulatively representing ~90% plant cover at each site. Long‐term drought led to increased community functional dispersion in three sites, with negligible effects on the remaining sites. Species re‐ordering following the mortality/senescence of dominant species was the main driver of increased functional dispersion. The response of functional diversity was not consistently matched by changes in phylogenetic diversity. Community‐level drought strategies (assessed as CWMs) largely shifted from drought tolerance to drought avoidance and/or escape strategies, as evidenced by higher community‐weighted πTLP, SLA and LNC. Lastly, ecosystem drought sensitivity (i.e. relative reduction in ANPP in drought plots) was positively correlated with community‐weighted SLA and negatively correlated with functional diversity. Synthesis. Increased functional diversity following long‐term drought may stabilize ecosystem functioning in response to future drought. However, shifts in community‐scale drought strategies may increase ecosystem drought sensitivity, depending on the nature and timing of drought. Thus, our results highlight the importance of considering both functional diversity and abundance‐weighted traits means of plant communities as their collective effect may either stabilize or enhance ecosystem sensitivity to drought.
State Lands in Modern Public Land Law

Two modern movements cast new light on the role of state lands in modern public land law, broadly conceived. A movement to “reclaim” public land from the federal government has resurfaced across the West — proponents want the United States to cede control and transfer these lands and their resources to the states. A wholly separate movement urges federal land reforms to keep fossil energy resources “in the ground” — to stop federal leasing for coal, oil, and gas — and to align federal land policy with the goal of climate change mitigation. Millions of acres of federal land have long supported a wide range of uses, from mining, oil and gas drilling, and renewable energy development, to grazing, recreation, and wilderness preservation. Although the legal regimes that govern competing values in federal lands are the subject of a deep literature, these movements remind us that publicly-owned lands are not just the federal holdings — state lands are also managed on behalf of the public, or subsets of the public, under very different legal frameworks that are less widely understood. This Article considers the role of state lands in modern public land law through its key contextual lens: energy development. It contrasts state and federal lands in the energy context at a time when headlines suggest state lands are becoming increasingly relevant to energy development — and not just in the West. Unique law and policy questions arise as an expanding energy sector creates pressure on state lands. From drilling in state parks to installing solar farms on state trust lands, the familiar statutes that structure energy resource extraction and facility siting on federal land are largely inapplicable to state lands. This Article provides critical context for understanding how broad national concerns over the uses of public land and the impacts of energy development on climate change and other environmental goals implicate state lands and their legal regimes.
The usefulness of HIV partner services in the age of treatment as prevention: a registry-based study.

Summary Background Partner services are effective tools to identify new cases among sex or needle-sharing partners of people with a new HIV diagnosis. Little is known about partners previously diagnosed with HIV who are not in care or are in care with unsuppressed HIV viral load. We aimed to quantify the previously diagnosed partners of people with a new HIV infection and examine their HIV care status and viral suppression in the 12 months before elicitation. Methods We did a registry-based study. We used the New York City HIV Surveillance Registry to determine HIV care status and viral load of partners elicited from newly diagnosed people between Jan 1, 2007, and Dec 31, 2018. Previously diagnosed partners with no report of CD4 count or viral load in the preceding 12 months were presumed not to be in care, viral load suppression ( Findings 11 964 partners were elicited; 2603 (33%) were previously diagnosed and 485 (20%) were not in care. 1153 (49%) of 2343 with a viral load report were in care and viraemic at elicitation. The odds of being not in care were higher in non-Hispanic black than non-Hispanic white or other partners (adjusted odds ratio 1·89, 95% CI 1·09–3·27) and lower in partners with male-to-male sex transmission risk (0·37, 0·26–0·51) and country of birth other than the USA (0·57, 0·39–0·85). The odds of being viraemic were higher in partners younger than 30 years than in those aged 30 years or older (1·68, 1·35–2·09) and lower among people with male-to-male sex transmission risk (0·36, 0·29–0·44) and country of birth other than the USA (0·78, 0·66–0·97). Interpretation People with HIV should receive ongoing HIV prevention counselling and partner services data should inform engagement in care for previously diagnosed partners. Funding None.
Consumer Perception of Food Expiration Labels: “Sell By” Versus “Expires On”

We design and conduct an experimental auction to investigate the effects of expiration labeling on consumers’ willingness to pay for food items. The experimental auction examines whether there is a valuation difference between “sell by” and “expires on” food labeling. We find that “sell by” date is perceived as an expiry date and consumers are willing to pay a premium for more clear information. In particular, “expires on” information about food expiry date has a 27% willingness to pay premium over “sell by” type labeling, showing that consumers prefer to avoid uncertainty in expiration information.
Behavioral strategies to reduce stress reactivity in opioid use disorder: Study design.

Objectives More than 2 million people in the United States had an opioid use disorder in 2017. Treatment for opioid use disorder-particularly medication combined with psychosocial support-is effective for reducing opioid use and decreasing overdose risk. However, approximately 50% of people who receive treatment will relapse or drop out. Stress reactivity, defined as the subjective and physiological response to stress, is heightened in people with opioid use disorder and higher stress reactivity is associated with poorer outcomes. Preliminary studies suggest that stress reactivity may be a key mechanistic target for improving outcomes. This article describes the design of an ongoing study examining behavioral strategies for reducing stress reactivity in adults with opioid use disorder. Our objective is to test the efficacy of two behavioral strategies for reducing stress reactivity and enhancing behavioral persistence in the context of stress (distress tolerance). Method We will recruit 120 adults with opioid use disorder and randomly assign them to brief training in (a) cognitive reappraisal, (b) affect labeling, or (c) a psychoeducational control. Participants will receive the training intervention followed by a laboratory stressor during which they will be instructed to apply the trained skill. Results Subjective and physiological responses to stress will be measured as indices of stress reactivity and the stressor task will include a behavioral persistence component as a measure of distress tolerance. Conclusions The ultimate goal of this study is to inform the development of behavioral interventions that can be used as an adjunct to medication-based treatment for opioid use disorder. (PsycInfo Database Record (c) 2020 APA, all rights reserved).
Electromagnetic control of spin ordered Mn3 qubits: a density functional study.

[Mn3O(O2CMe)(dpd3/2)]2 is composed of two monomers each of which contain three Mn atoms at the vertices of an equilateral triangle. A full analysis of the electronic and magnetic structure of the dimer shows that each Mn atom carries a local spin of S = 2 while other spin states are energetically much higher. This result suggests application for conventional as well as quantum tasks. A detailed analysis of the electronic and magnetic structure of the monomer, on the other hand, suggests that there are three spin states of S = 1, S = 3/2 and S = 2 per monomer which are energetically competitive. We found that while monomer–monomer interactions are very weak, the coupling of monomers via covalent linkers affects both the magnetization and electronic energy levels of monomers. In particular, the isolated monomers prefer a ground state with local spin of S = 1 on Mn atoms and an antiferromagnetically ordered structure while the dimers possess a ground state with local spin of S = 2 on Mn atoms and a ferromagnetically ordered structure. The investigation of the polarizability of both monomer and dimer is examined for antiferromagnetically ordered structures which induces a high dipole moment of 0.08 (a.u.) and 0.16 (a.u.) for monomer and dimer, respectively. The energy of the antiferromagnetic structure is also high compared to other spin-electric molecules.
Racial Disparities in Readmissions Following Initial Hospitalization for Sepsis.

OBJECTIVES To assess whether Black race is associated with a higher rate of all-cause readmission compared with White race following community-onset sepsis. DESIGN Retrospective cohort study. SETTING One-thousand three-hundred bed urban academic medical centers. PATIENTS Three-thousand three-hundred ninety patients hospitalized with community-onset sepsis between January 1, 2010, and December 31, 2017. INTERVENTIONS Community-onset sepsis was defined as patients admitted through the emergency department with an International Classification of Disease, ninth revision, Clinical Modification code for either severe sepsis (995.92) or septic shock (785.52). Beginning in 2015, we used International Classification of Disease, Tenth Revision, Clinical Modification codes R65.20 (severe sepsis) and R65.21 (septic shock). We excluded those individuals hospitalized at another acute care facility that were transferred to our facility. Race was abstracted electronically, and patients who expired or self-identified as a race other than Black or White race were excluded. Patients who experienced a subsequent hospitalization at our facility were considered to be readmitted. MEASUREMENTS AND MAIN RESULTS Compared with White race, Black race demonstrated a significantly higher rate of all-cause readmission (60.8% vs 71.1%; p < 0.001), including a higher rate of readmission for sepsis (14.0% vs 19.8%; p < 0.001). Black patients also resided in zip codes with a lower median household income and were more likely to use public insurance compared with White race. Similar rates of comorbid diseases and disease burden were observed between the two groups, but vasopressors were less likely to be administered to Black patients. Multivariable analysis showed that Black race was associated with a 50% increased odds (odds ratio, 1.52, 99% CI, 1.25-1.84) in all-cause readmission risk compared with White race. CONCLUSIONS Black race was associated with a higher rate of all-cause and sepsis readmission, possibly as a result of unaddressed health disparities, compared with White race. Programs addressing healthcare disparities should use readmission as another marker of equity.
Rethinking Self-Regulation: Antitrust Perspectives on Bar Governance Activity

This article discusses the American bar’s unfortunate over-protection against the unauthorized practice of law and the ways that the Supreme Court’s recent ruling in North Carolina Board of Dental Examiners v. Federal Trade Commission suggests that their anticompetitive practices may face new hurdles. The article surveys the background of federal antitrust doctrine and describes the scope and rationale of the Dental Examiner’s ruling. The article then offers some thoughts on the implications of the decision for bar regulatory activities, including a recent example involving the North Carolina bar’s UPL action against LegalZoom. We close with some suggestions about how the bar should proceed going forward, concluding that the Supreme Court may have mapped a route forward for saner regulation of the market for legal services. If we are right, society as a whole will benefit.
Access to cancer care for Medicaid patients at cancer hospitals in the United States.

6548Background: As the result of expansions associated with the Affordable Care Act (ACA), one in five Americans are now insured through Medicaid. Despite overall increases, access to care for Medi...
Filtration Performance of Layering Masks and Face Coverings and the Reusability of Cotton Masks after Repeated Washing and Drying

ABSTRACT In this study, filtration efficiency of different respirators, face masks, and a 2-ply cotton handkerchief bandana was compared for particles in the size range of 60 nm–4 µm under a “perfect fit” condition. The filtration efficiency at the most penetrating particle size of 0.3 µm on average ranged from 83–99% for N95 and KN95 respirators, 42–88% for surgical masks, 16–23% for cloth masks, and 9% for bandana. We also investigated the effects of using double surgical masks or layering a cloth mask over various surgical masks in terms of their filtration characteristics. In most of these combinations, the filtration efficiency improved by ~25% for particles 0.3–1 µm in diameter without any substantial change in the filter quality factor when compared to the highest of the individual mask results. To investigate the reusability of cotton cloth masks, 2-layer cotton fabric sample coupons were machine washed and dried for 52 cycles leading to an increase in inhalation resistance (~20 Pa) without affecting size-resolved filtration efficiency. Scanning electron microscopy revealed that washing and drying led to the gradual deconstruction of cotton fibers at the scale of several micrometers to hundreds of nanometers in the form of delamination of the fiber wall and fibrillation of the nanofiber constituents. Results indicate that cloth masks may be layered over surgical masks for additional benefits, and that cloth masks made out of cotton fabric can be washed and reused numerous times without a significant loss in filtration efficiency.
Imaging for the Assessment and Management of Cardiovascular Disease in Women and Minority Populations

Significant disparities exist in the prevalence and clinical presentation of cardiovascular disease among individuals of different ethnicity/race and sex, with minority populations being affected in a disproportionate manner. The use and value of various imaging modalities for the assessment of cardiovascular disease are clearly impacted by such inequalities. In contemporary medicine, with the goal of patient-centered practice, we must aim to provide valuable medical care by acknowledging these variations and tailoring our assessment to each individual patient with consideration of these factors and their impact in their care. In this chapter, we discuss the available data regarding the advantages and limitations of specific imaging techniques. Additionally, differences related to minority populations must be recognized, so as to allow an appropriate use of these resources and foster more accurate conclusions, leading to the establishment of a proper and individualized treatment strategy for patients of diverse populations.
The Utilization of Supplemental Choline by Brain

The disposition and metabolism of choline and its utilization for the synthesis of acetylcholine (ACh) in brain have been the subject of numerous investigations (for reviews see 2, 3, 4, 18). Although it is well established that following administration, choline is rapidly incorporated into ACh in brain (11, 20, 28, 29), the ability of supplemental choline to increase the steady-state concentration of ACh is questionable. Studies in my laboratory have indicated that the acute administration of choline does not increase the concentration of ACh in brain under “normal” biochemical and physiological conditions, but it does provide choline that can be used to support the synthesis of ACh when there is an increased demand for the precursor, i.e., when the activity of central cholinergic neurons is increased (32, 36). Choline, administered either as a salt or in the form of phosphatidylcholine (PTC), prevents the depletion of ACh in brain induced by atropine, fluphenazine or pentylenetetrazol, when choline is administered acutely prior to these agents that increase cholinergic neuronal activity (14, 21, 27, 31, 33, 38). In addition, prior administration of choline has been shown to prevent opiate withdrawal-induced decreases in the levels of ACh in hippocampus (8). Hence, data suggest that choline enhances the synthesis of ACh during conditions of drug-induced increases in neuronal demand. This idea is further substantiated by studies in the perfused hemidiaphragm preparation, indicating that the release of ACh following phrenic nerve stimulation is enhanced by the presence of choline in the perfusate only when the rate of nerve stimulation is increased (7). Hence, most data, with the exception of one report in which large doses of choline were used that may have decreased the turnover of ACh (30), support the hypothesis that supplemental choline, via acute administration, is used to enhance the synthesis of ACh under conditions of increased neuronal demand.
A Compact Front-end Electronics Module for the SDC Strawtube Outer Tracker

The challenges of building a detector for the Superconducting Super Collider have been talked about for the last several years. Those challenges are proving to be real and in some cases tougher than expected as prototype subsystem and component development continues within the different collaborations. Not to be daunted, engineers and scientists are using ingenuity and novel designs to meet the challenges. One such area has been in the development of the outer tracker readout electronics for the Solenoidal Detector Collaboration (SDC) detector. The tracker has over 100,000 channels and is composed of strawtubes that are 4 mm in diameter and 4 meters long. The sheer number of channels and small-diameter tubes require a very high density packaging scheme with critical attendant concerns, including power consumption, cooling, and crosstalk. This paper describes the novel approach taken to solve some of these challenges.
Physical characteristics and sex hormone levels in patients with osteoporotic hip fractures or endometrial cancer

Abstract Comparisons were made of the physical characteristics and the sex hormone levels of 50 postmenopausal women, half of whom had sustained an osteoporotic hip fracture while the remainder had developed endometrial carcinoma. None of the patients had received estrogen replacement therapy for longer than 3 months during their lifetime. At the time of injury hip fracture patients were found to be lighter (121 ± 5 versus 167 ± 9 pounds) and older (73.4 ± 1.0 versus 62.6 ± 1.7 years) than the cancer patients at the time of diagnosis. Estrone, estradiol, percentage of free estradiol, and free estradiol levels were significantly lower in the hip fracture patients than in subjects with endometrial cancer, while sex hormone-binding globulin levels were significantly higher in the former group. Androstenedione and testosterone levels were similar. Previous studies have shown that the incidence of both lesions is influenced by body size. These data suggest that body size may exert this influence through alteration of endogenous estrogen metabolism with hip fracture patients having lower concentrations and endometrial cancer patients having higher concentrations of endogenous estrogens.
Symbolic Synthesis of Supervisory Controllers

Ramadge and Wonham [1] gave algorithms for finding controllers in their supervisory control framework. Their automatic synthesis techniques are implemented here using binary decision diagrams [2]. This technique of symbolic representation capitalizes on loose coupling between controlled plant components. We are able to synthesize a controller for a wafer-manufacturing plant, for which an explicit representation would have about 106 states.
Simplified seawater alkalinity analysis: Use of linear array spectrometers

Abstract Modified spectrophotometric procedures are presented for the determination of seawater total alkalinity using rapid scan linear array spectrometers. Continuous monitoring of solution pH allows titrations to be terminated at relatively high pH, whereby excess acid terms are very small. Excess acid concentrations are quantified using the sulfonephthalein indicators, bromocresol green and bromocresol purple. The outlined spectrophotometric procedures require no thermal equilibration of samples. Using bromocresol green, solution pH T ([H + ] T in moles per kg of solution) is given as: pH T =4.2699+0.002578(35− S )+ log ((R(25)−0.00131)/(2.3148−0.1299 R (25))) − log (1−0.001005S) and R (25)= R ( t ){1+0.00909(25− t )}, where 29⩽S⩽37, 13° C ⩽t⩽32° C , and R ( t ) is the absorbance ratio ( A 616 / A 444 ) at temperature t and salinity S. Using bromocresol purple, the solution pH T is given as pH T =5.8182+0.00129(35− S )+log(( R (25)−0.00381)/(2.8729−0.05104 R (25))) and R (25)= R ( t ){1+0.01869(25− t )}, where 29⩽S⩽37, 13° C ⩽t⩽32° C , and R ( t )= A 589 / A 432 . Alkalinity measurements using bromocresol purple had a precision on the order of 0.3 μmol kg -1 and were within 0.3–0.9 μmol kg -1 of the alkalinities of certified seawater reference materials.
Phenomenology and Epidemiology of Mood Disorders in Children and Adolescents

Until recently, researchers lacked standardized assessment instruments and formal criteria to use in making a mood disorder diagnosis in children and adolescents. These two methodological developments have been fundamental to making mood disorders in youth, particularly depression in childhood, one of the most active areas of research within child psychiatry (Mokros & Poznanski, 1992). Indeed, many review articles and several books devoted exclusively to childhood depression have now been published (e. g., Schulterbrand & Raskin, 1977; Cantwell & Carlson, 1983; Petti, 1983; Weller & Weller, 1984; Cicchetti & Schneider-Rosen, 1984; Rutter, Izard, & Read, 1986; Shafii & Shafii, 1992).
The synthesis of 2-alkyl-4-pyrones from meldrum's acid

The synthesis of 2-alkyl-4-pyrones from Meldrum's acid intermediate: 5-(1-Hydroxyethylidene)-2,2-dimethyl-1,3-dioxane-4,6-dione product: 2-methyl-4H-pyran-4-one Keywords: acylation; addition, to CCCO and CCCN; annulation, heterocyclic-[6]; annulation, heterocyclic-[6]; cyclization, condensation; cyclization, cycloaddition; decarboxylation; Diels-Alder reactions; elimination, miscellaneous
An evaluation of soft tissue responses following removal of ill-fitting dentures☆☆☆

Abstract An investigation was conducted on the changes in the thickness of the soft tissues after ill-fitting dentures had been left out of the mouths of 14 subjects for 72 hours. Periapical radiographs were made before and after resting the soft tissues, and the thickness of the soft tissues was measured on the radiographs. A comparison of these measurements showed an average increase of 0.136 mm in thickness of the soft tissues before and after leaving the dentures out of the mouth.
Kinetic Structure of Large-Conductance Ca2+-activated K+ Channels Suggests that the Gating Includes Transitions through Intermediate or Secondary States : A Mechanism for Flickers

Mechanisms for the Ca2+-dependent gating of single large-conductance Ca2+-activated K+ channels from cultured rat skeletal muscle were developed using two-dimensional analysis of single-channel currents recorded with the patch clamp technique. To extract and display the essential kinetic information, the kinetic structure, from the single channel currents, adjacent open and closed intervals were binned as pairs and plotted as two-dimensional dwell-time distributions, and the excesses and deficits of the interval pairs over that expected for independent pairing were plotted as dependency plots. The basic features of the kinetic structure were generally the same among single large-conductance Ca2+-activated K+ channels, but channel-specific differences were readily apparent, suggesting heterogeneities in the gating. Simple gating schemes drawn from the Monod- Wyman-Changeux (MWC) model for allosteric proteins could approximate the basic features of the Ca2+ dependence of the kinetic structure. However, consistent differences between the observed and predicted dependency plots suggested that additional brief lifetime closed states not included in MWC-type models were involved in the gating. Adding these additional brief closed states to the MWC-type models, either beyond the activation pathway (secondary closed states) or within the activation pathway (intermediate closed states), improved the description of the Ca2+ dependence of the kinetic structure. Secondary closed states are consistent with the closing of secondary gates or channel block. Intermediate closed states are consistent with mechanisms in which the channel activates by passing through a series of intermediate conformations between the more stable open and closed states. It is the added secondary or intermediate closed states that give rise to the majority of the brief closings (flickers) in the gating.
The moment map and collective motion

Abstract Given a Hamiltonian action of a Lie group G on a symplectic manifold M there is an induced map Φ: M → g ∗ where g ∗ is the dual space to the Lie algebra, g, of G. The map Φ is called the moment map. Any function P on g ∗ then gives rise to a function F = P ∘ Φ on M which is a “collective Hamiltonian” associated to the group action G. We show how the rigid rotor, liquid drop, and other collective models of the nucleus fit into this framework. We describe the steps involved in integrating collective equations of motion and indicate some principles involved in the choice of collective Hamiltonians, i.e., the functions P. We discuss these constructions in some detail for the case that G is a semidirect product.
A Critical View of Worker Participation in American Industry

Some analysts of worker participation have argued that it does not improve productivity as much as its proponents suggest, while others argue that it is an effective catalyst for expanding worker control over the labor process. This article examines the experience of worker participation and finds that the tendency is for such programs to weaken unions and limit workers' power in significant ways. In union workplaces, such programs disable existing grievance mechanisms and worker solidarity, while transferring knowledge from workers to management. In nonunion settings, worker participation programs can promote managerial attitudes, while either supplanting or preventing unionism.
Optimization of Protein Production in Mammalian Cells with a Coexpressed Fluorescent Marker

The expression of mammalian proteins in sufficient abundance and quality for structural studies often presents formidable challenges. Many express poorly in bacterial systems, whereas it can be time consuming and expensive to produce them from cells of higher organisms. Here we describe a procedure for the direct selection of stable mammalian cell lines that express proteins of interest in high yield. Coexpression of a marker protein, such as green fluorescent protein, is linked to that of the desired protein through an internal ribosome entry site in the vector that is transfected into cells in culture. The coexpressed marker is used to select for highly expressing clonal cell lines. Applications are described to a membrane protein, the 5HT2c serotonin receptor, and to a secreted cysteine-rich protein, resistin. Besides providing an expeditious means for producing mammalian proteins for structural work, the resulting cell lines also readily support tests of functional properties and structure-inspired hypotheses.
Headache in the Emergency Department

Objective.—To perform an observational study of the demographics, clinical factors, and therapeutic efficacy in patients presenting to the emergency department with a chief complaint of headache. Background.—Acute headache presentations to the emergency department are a therapeutic dilemma for physicians. Methods.—Patients presenting with nontraumatic headache to the emergency department of Hermann Hospital in Houston, Texas, during a 16-month period were prospectively ascertained by active and passive surveillance. The medical record was abstracted. Demographic and clinical information are presented with descriptive statistics. Relative benefit of individual therapies are compared with odds ratios (95% confidence intervals). Results.—Of the 38 730 patients who were prospectively screened, 455 presented with a chief complaint of headache. Seventy-six percent were women, and the mean age was 37 years. Non-Hispanic whites were more likely diagnosed with migraine compared with Hispanics or African Americans (P<.001). Three percent had subarachnoid hemorrhage. Neurologist follow-up was ordered in 10%. The median time in the emergency department was 265 minutes. With the initial treatment, 44% resolved, 47% improved, and 9% had no change; none worsened. In comparison with all other therapies used, there was a trend suggesting the superiority of antiemetics (odds ratio, 2.66; 95% confidence interval, 0.81 to 8.61). Acetaminophen was less helpful (odds ratio, 0.27; 95% confidence interval, 0.10 to 0.70). When comparing specific agents to therapies which could be used at home, antiemetics led to headache resolution most often (odds ratio, 3.18; 95% confidence interval, 1.40 to 7.22); ketorolac showed a similar trend (odds ratio, 2.05; 95% confidence interval, 0.86 to 4.89). Conclusions.—Headache in the emergency department is a phenomena of young women who spend a long time waiting and receive many tests. A variety of therapies are used. Antiemetics may be especially useful for headache resolution.
Migration and Differentiation of Cerebral Cortical Neurons After Transplantation into the Brains of Ferrets

Cells from the cerebral proliferative zones of newborn ferrets were labeled with tritiated thymidine and a fluorescent dye and were transplanted as a single-cell suspension into the occipital region of newborn ferrets. The transplanted cells became thoroughly integrated into the host environment: many cells migrated through the intermediate zone and into the cortical plate, where they developed as pyramidal neurons. Other transplanted cells came to resemble glial cells. After 1 to 2 months most transplanted neurons had taken up residence in layer 2 + 3, the normal destination of neurons generated on postnatal days 1 and 2. Thus the sequence of morphological differentiation and the eventual laminar position of the isochronically transplanted neurons closely paralleled that of their normal host counterparts.
Treatment of metastatic retinoblastoma.

Abstract Purpose The risk for death in patients with retinoblastoma is increased in those who present with metastatic disease, and the role of intensive chemotherapy and autologous hematopoietic stem cell rescue in these patients remains unclear. Design Nonrandomized interventional case series. Participants Four consecutive patients with metastatic retinoblastoma. Methods We treated four patients with retinoblastoma metastatic to the bone and bone marrow with intensive chemotherapy, consolidation with megatherapy, and autologous hematopoietic stem cell rescue. Chemotherapy included courses of carboplatin and etoposide alternating with cyclophosphamide, etoposide, and either carboplatin or cisplatin. Radiation therapy was delivered to areas of bone metastases. Main outcome measures Patient survival. Results All patients completed and responded to the scheduled therapy; complete response of the bone marrow disease was documented after two courses of chemotherapy in all cases. Two patients are long-term survivors. Conclusions The treatment described has been successful in obtaining disease-free survival in patients with metastatic retinoblastoma.
In vitro metabolism of chlorpheniramine in the rabbit

The in vitro metabolism of 3-(p-chlorophenyl)-3-(2-pyridyl)-N, N-dimethylpropylamine (chlorpheniramine, I) by rabbit liver microsomes was examined. The metabolites, tentatively identified by gas-liquid chromatography-mass spectrometry, included the mono- and didemethyl metabolites, the aldehyde that results from deamination, and further metabolites of this aldehyde including its intramolecular cyclization product, an indolizine, and its reduction product, the alcohol. Inhibition of metabolism of I by N2, CO, SKF-525A, 2,4-dichloro-6-phenylphenoxyethylamine (DPEA), or deletion of NADPH implies some involvement of cytochrome P-450 in the metabolic reactions. Quantitation of metabolism in these studies accounted for only 69% of the dose, so that binding and/or other undetected metabolic pathways were operative.
Mice Lacking the Integrin β5 Subunit Have Accelerated Osteoclast Maturation and Increased Activity in the Estrogen-Deficient State†

Integrin αvβ5 is expressed on osteoclast precursors and is capable of recognizing the same amino acid motif as αvβ3. Three-month-old β5−/− female OVX mice had increased osteoclastogenesis ex vivo, and μCT assessment of trabecular bone volume was 53% lower than WT-OVX animals. These preliminary data suggest αvβ5 integrin's presence on osteoclast precursors may inhibit of osteoclast formation. Introduction: Osteoclasts are unique resorptive skeletal cells, capable of degrading bone on contact to the juxtaposed matrix. Integrin αvβ5 is expressed on osteoclast precursors, structurally similar to αvβ3, and capable of recognizing the same amino acid motif. Given the structural relationship and reciprocal regulation of αvβ3 and αvβ5, the purpose of this study was to evaluate how αvβ5 might contribute to osteoclast maturation and activity. Materials and Methods: Three-month-old wildtype (WT) and β5−/− female mice had ovariectomy (OVX) or sham operations. The osteoclastogenic capacity of marrow-derived precursors, the kinetic, the circulating, and structural parameters of bone remodeling, was determined after 6 weeks of paired feeding. Results and Conclusions: OVX increased osteoclastogenesis ex vivo and in vivo. Osteoclast formation and prolonged pre-osteoclast survival were substantially enhanced in cultures containing β5−/− cells whether obtained from sham-operated or OVX mice. Expression of cathepsin K, β3 integrin subunit, and calcitonin receptor were accelerated in cultured β5−/−osteoclasts. β5−/− osteoclasts from OVX animals showed a 3-fold enhancement of net resorptive activity, with quantitative μCT showing trabecular bone volume loss after OVX 53% greater in β5−/− OVX compared with similarly treated WT OVX mice (p < 0.05). α5β3 seems to be an inhibitor of osteoclast formation, in contrast to αvβ3. In addition, loss of αvβ5 seems to accelerate osteoclast formation in the OVX model. Further examination of αvβ5 signaling pathways may enhance our understanding of the activation of bone resorption.
Synthesis and technetium-99m labeling of cyclic GP IIb/IIIa receptor antagonists conjugated to 4,5-bis(mercaptoacetamido)-pentanoic acid (mapt)

Abstract The synthesis of cyclic Arg-Gly-Asp GP IIb/IIIa receptor antagonists conjugated to 4,5-bis(S-1-ethoxyethyl-mercaptoacetamido)pentanoic acid is reported. The corresponding Tc-99m-labeled complexes were prepared by exchange labeling with Tc-99m-glucoheptonate. This indirect labeling approach is an alternative to the preformed chelate approach using mapt.
Pulsed Laser Deposition Of Amorphous Carbon Films

We have deposited thin amorphous carbon films on various substrate materials by irradiating a high purity (5N) graphite target in vacuum with pulsed light at 248 nm from a KrF excimer laser. The films have been characterized by Raman scattering, AES, SEM and chemical inertness tests. The films deposited on silicon are smooth and partially transparent. The preliminary Raman spectra show no evidence of crystalline grains (diamond or graphite) however the films deposited on silicon and quartz survived etching by a solution of HF:HNO 3 (1:1). We will report on the substrate temperature dependence of laser deposited films and the variation of film quality on substrate material.
Expression of prokineticins and their receptors in the adult mouse brain

Prokineticins are a pair of regulatory peptides that have been shown to play important roles in gastrointestinal motility, angiogenesis, circadian rhythms, and, recently, olfactory bulb neurogenesis. Prokineticins exert their functions via activation of two closely related G-protein-coupled receptors. Here we report a comprehensive mRNA distribution for both prokineticins (PK1 and PK2) and their receptors (PKR1 and PKR2) in the adult mouse brain with the use of in situ hybridization. PK2 mRNA is expressed in discrete regions of the brain, including suprachiasmatic nucleus, islands of Calleja and medial preoptic area, olfactory bulb, nucleus accumbens shell, hypothalamic arcuate nucleus, and amygdala. PK1 mRNA is expressed exclusively in the brainstem, with high abundance in the nucleus tractus solitarius. PKR2 mRNA is detected throughout the brain, with prominent expression in olfactory regions, cortex, thalamus and hypothalamus, septum and hippocampus, habenula, amygdala, nucleus tractus solitarius, and circumventricular organs such as subfornical organ, median eminence, and area postrema. PKR2 mRNA is also detected in mammillary nuclei, periaqueductal gray, and dorsal raphe. In contrast, PKR1 mRNA is found in fewer brain regions, with moderate expression in the olfactory regions, dentate gyrus, zona incerta, and dorsal motor vagal nucleus. Both PKR1 and PKR2 are also detected in olfactory ventricle and subventricular zone of the lateral ventricle, both of which are rich sources of neuronal precursors. These extensive expression patterns suggest that prokineticins may have a broad array of functions in the central nervous system, including circadian rhythm, neurogenesis, ingestive behavior, reproduction, and autonomic function.
Response of males to female-initiated dates

Males’ experience with and attitudes toward the initiation of dating by females were explored. On a university campus, 97 male undergraduates responded to a questionnaire dealing with this topic. Most males verbalized positive reactions to the prospect of female initiation, but females apparently were unable to discriminate between those who were and were not receptive. Thus, attitudes about female initiation were unrelated to the probability of receiving such an invitation, but those males with a positive orientation were most likely to accept and to be asked out on subsequent occasions. Continued initiations by a female seldom met with success, and few of the female-initiated relationships were maintained. It was also found that older males had fewer experiences with requests from women and a lower dating frequency. The discrepancy between the positive attitudes expressed by males and the relative lack of success of these interactions suggest that female initiation elicits some degree of negative affect among male recipients.
The thermodynamics of the hydrogen-iron system

Abstract New data have been presented for the temperature variation of the hydrogen solubility in both polycrystalline and single-crystal iron, of differing purity grades, in equilibrium with H 2 gas at one atmosphere pressure. An analysis of these data and previous solubility measurements has shown a deviation from Arrhenius behavior. In the temperature range from ~300 °C up to the α/γ transformation temperature, the solubility is largely insensitive to chemical composition and the presence of grain boundaries. The curved Arrhenius plot has been discussed in terms of several possible mechanisms including the formation of HH complexes, the presence of trapping sites, and the simultaneous occupation of both tetrahedral and octahedral sites in the b.c.c. lattice by H atoms.
Amyloid fibrils are “alive”: spontaneous refolding from one polymorph to another

Mature fibrils prepared from apo-α-lactalbumin spontaneously refold from one polymorph to another as a result of a mild alteration in solution temperature and salinity. This discovery changes the very concept of the extraordinary stability of amyloid fibrils and presages a new approach for potentially regulating the biological activity of fibrils and their associated toxicity.
Ethnic Identity Development and Urban Haitian Adolescents.

This experimental study describes the effect of a preventive, psychoeducational, counselor intervention on the ethnic identity development of urban Haitian adolescents. Significant differences were found for gender but not between the control and experimental groups. Boys scored significantly lower (p < .05) than girls on the Multigroup Ethnic Identity Measure. Recommendations are made regarding school as a frontier for the enhancement of healthy minority adolescent development.
Alexithymia in Patients Attending a Sexual Disorders Clinic

We measured alexithymic traits with the Toronto Alexithymia Scale (TAS; Bagby, Taylor, & Parker, 1988) in 170 individuals attending a sexual disorders clinic. We diagnosed 114 of the subjects with a sexual dysfunction and 56 with paraphilic disorders. We determined that 20.2% of the dysfunctional group and 26.8% of the paraphilic were alexithymic when the TAS was measured categorically. When we considered the TAS as a dimensional variable, the subset with paraphilias had significantly higher scores on the TAS only when depressed mood, as measured by the Brief Symptom Inventory (Derogatis, 1993), was covaried. These data suggest that alexithymia in both sexually dysfunctional and paraphilic individuals is related to depressed mood, although the effect is more pronounced in paraphilics.
Reactivity in baseline accelerometer data from a physical activity behavioral intervention.

OBJECTIVE This brief report describes the possibility of reactivity in the baseline assessment of physical activity using accelerometry from two separate randomized controlled trials of a behavior intervention for increasing physical activity in persons with multiple sclerosis (MS). METHOD The samples included 18 persons with multiple sclerosis (MS) from Study 1 and 20 from Study 2 who were randomized into treatment arms of the intervention. The participants initially wore an accelerometer over a 7-day period for collection of baseline data, and one week later wore a pedometer over a 7-day period for collection of data for self-monitoring and goal setting in week 1 of the 12-week intervention. The accelerometer and pedometer data were both expressed in average steps per day over a 7-day period. RESULTS There was a moderate (d = .56), statistically significant (p = .03) difference of 1,822 steps per day between baseline and week 1 of the intervention in Study 1. There was a large (d = 1.36), statistically significant (p = .0001) difference of 2,338 steps per day in Study 2. CONCLUSION We are unaware of other research describing a significant change in physical activity between baseline and the first week of a behavioral intervention and believe that this change reflects reactivity in the baseline assessment using accelerometry.
A visualization and measurement environment for software engineering

Work is reported on the development and enhancement of the GRASP software engineering and visualization tool. GRASP automatically produces visualizations of control and complexity (control structure diagrams and complexity profile graphs, respectively) of source code written in Ada 95, C, and Java. These visualizations use intuitive, compact graphical representations that allow the software engineer to holistically visualize the overall program as well as visualize the details of a small section of the code. Current features and enhancements of GRASP as well as its availability are discussed.