cssi/SciSciGPT-SciSciNet huggingface dataset:
Impact of a surgical site infection bundle on cesarean delivery infection rates.

Background This study investigated cesarean delivery surgical site infection (SSI) rates before and after implementation of a SSI care bundle. Methods A SSI bundle for cesareans was introduced in our hospital in April 2014 to reduce the SSI rate. The practices were divided into bundle elements that reflected preoperative, intraoperative, and postoperative care. We conducted a retrospective cohort study to evaluate implementation of the SSI care bundle. Women were included if they had a gestational age of at least 23 0/7 weeks and delivered a liveborn neonate(s) between 2012 and 2015. They were then divided into 2 study groups: pre-bundle and post-bundle. The primary study outcome was SSI rate. Secondary outcomes included comorbidities, perioperative factors, and SSI classification. Results The overall incidence of cesarean SSIs during the study time period was 1.89 (76 SSIs in 4014 cesarean deliveries). The pre-bundle mean was 2.44 and decreased to 1.1 following implementation of the SSI bundle (P = .013). This represents a 221% reduction in the SSI rate. Patient demographics and pre-existing medical conditions were similar pre- and post-bundle. Compliance with bundle elements was high. Conclusions A significant reduction in SSI rate in cesarean deliveries was seen following implementation of an infection prevention bundle.
Open pronation abduction ankle fractures associated with increased complications and patient BMI.

Abstract Introduction Pronation abduction (PA) ankle fractures are often associated with a medial tension failure wound. Though this injury pattern was defined based on the mechanism of injury, there is a paucity of literature evaluating risk factors for understanding which patients will sustain an open PA fracture. Furthermore, how patients with these types of fractures perform relative to other open ankle fractures has not been established. We hypothesized that open PA fractures are associated with obesity and increased number of reoperations. Methods All patients at a single level one trauma center who received operative treatment for an ankle fracture between February 2012 to January 2019 were retrospectively identified using Current Procedural Terminology (CPT) codes. Patients with open PA ankle fractures were identified. Demographic data, body mass index, medical comorbidities, time to surgery, and reoperations were compared between open PA ankle fractures and other open ankle fracture subtypes. Results There were 22 open PA ankle fractures and 35 other open ankle fracture subtypes. The open PA fracture group had a significantly higher median and average BMI and percentage of patients with obesity. There was no difference in number of patients requiring reoperation between the two groups. When reoperation was required, patients with open PA ankle fractures were found to undergo significantly more reoperations and were significantly more likely to require arthrodesis or below knee amputation. Conclusions Open PA ankle fractures are more often associated with obesity (BMI > 30 kg/m2) than are other open ankle fractures caused by a different mechanism. When reoperation does occur, patients with open PA ankle fractures require more reoperations and are more likely to require arthrodesis or below knee amputation that patients with other open ankle fracture subtypes. Early identification of those patients or injuries at increased risk of complications can help ensure optimal outcomes.
Performance Evaluation and Analysis of Proactive and Reactive MANET Protocols at Varied Speeds

A Mobile Ad Hoc Network (MANET) is a decentralized wireless network that does not rely on pre-existing infrastructure. Instead, it is each node's responsibility to forward data according to its specified routing protocol. Although these protocols perform the same task, their performance in a variety of scenarios differ. This paper simulates four different routing protocols in NS-3 at a variety of movement speeds and area sizes, comparing their Packet Delivery Ratio (PDR) and Average End-To-End Delay (AETED). The performance results reflect what would be expected if a system would be implemented in a similar environment. Therefore, it is crucial selecting a protocol to best suit a system.
Bowman's layer in the cornea– structure and function and regeneration

Abstract Bowman's layer lies immediately posterior to the epithelial basement membrane (EBM) and anterior to the stroma proper in humans, chickens, quail, zebra fish, deer, giraffe, antelope, California sea lions, guinea pig and several other species. It is not found in dog, wolf, cat, tiger, lions, rabbit, pigs, cows, goats, or horses. Developmental anomalies of Bowman's layer are rare, but acquired damage to Bowman's layer, or even complete destruction, is frequently seen in advanced bullous keratopathy or Fuchs' endothelial dystrophy. No detrimental effects of removal of Bowman's layer over the central 6–7 mm of central cornea have been noted in millions of patients who've had photorefractive keratectomy (PRK). Recent studies have suggested the randomly-oriented collagen fibrils that make up Bowman's layer do not have a significant barrier function in modulating the passage of moderate- to large-sized proteins. It is hypothesized that Bowman's layer develops in the corneas of those species that have one because of cytokine-mediated interactions occurring between corneal epithelial cells and underlying keratocytes, including negative chemotactic and apoptotic effects on the keratocytes by low levels of cytokines such as interleukin-1α that are gradually released as epithelial cells die and slough during their normal development. A “Bowman's like layer” can generate around stromal epithelial plugs after radial keratotomy, and possibly beneath the central corneal epithelial basement membrane many years after PRK.
Towards a realistic explosion landscape for binary population synthesis

A crucial ingredient in population synthesis studies involving massive stars is the determination of whether they explode or implode in the end. While the final fate of a massive star is sensitive to its core structure at the onset of collapse, the existing binary population synthesis studies do not reach core-collapse. Instead, they employ simple prescriptions to infer their final fates without knowing the presupernova core structure. We explore a potential solution to this problem by treating the carbon-oxygen (CO) core independently from the rest of the star. Using the implicit hydrodynamics code KEPLER, we have computed an extensive grid of 3496 CO-core models from a diverse range of initial conditions, each evolved from carbon ignition until core-collapse. The final core structure, and thus the explodability, varies non-monotonically and depends sensitively on both the mass and initial composition of the CO-core. Although bare CO-cores are not perfect substitutes for cores embedded in massive stars, our models compare well both with MESA and full hydrogenic and helium star calculations. Our results can be used to infer the presupernova core structures from population synthesis estimates of CO-core properties, thus to determine the final outcomes based on the results of modern neutrino-driven explosion simulations. A sample application is presented for a population of Type-IIb supernova progenitors. All of our models are available at this https URL.
Trauma-Informed Care Training for Educators: Some Preliminary Evidence:

A report of the findings of two studies conducted on the training of educators on trauma-informed care (TIC) is presented in this article. With one sample (N = 552), Study 1 results indicated that ...
Spacecraft Attitude Control

Spacecraft pointing control is an essential technology for all robotic and manned spacecraft. A control system consists of sensing, actuation, and the dynamics of the spacecraft itself. Spacecraft control systems are of many types, but in this chapter, we will be concerned only with three axis pointing. We will use reaction wheels for actuation.
Patterns of General Surgery Residency Social Media Use in the Age of COVID-19.

OBJECTIVE The role for social media use by General Surgery departments continues to expand and social media accounts have been increasingly implemented as a tool for residency program for promotion and engagement. The importance of these accounts appears to have increased given the unprecedented changes with COVID-19 and the dramatic and unpredictable change to the application cycle including the use of virtual interviews, suggesting a perceived need for increased online engagement with applicants. The purpose of this study was to determine the patterns of creation and usage of Twitter and Instagram accounts of Accreditation Council for Graduate Medical Education (ACGME)-accredited General Surgery residency programs and their associated surgical departments. METHORDS A cross-sectional study of the use of Twitter and Instagram by the 332 ACGME-accredited General Surgery residency programs and their associated departments was conducted in February 2021. Twitter and Instagram accounts were identified by accessing program/department websites as well as social media platform and internet searches. Year of creation, number of followers, and number of posts (July 1, 2018-December 31, 2020) were collected. Trends in usage were compared across years stratified by platform and by account owner (department vs. residency). RESULTS Instagram accounts are more than five-times greater for residencies compared to departments (42% vs 8%, p Conclusions The number of residency social media accounts has significantly increased in 2020 compared to account creation of departments, with Instagram account creation exceeding that of Twitter and of departments. The opposite pattern in usage was seen related to number of posts, and with Twitter, followers, and number of followings, with departments outpacing residencies. This significant increase in account creation may have been influenced by the COVID-19 pandemic and the change to a virtual interview season, suggesting an unprecedented need for online engagement with applicants. As the increased social media presence will likely persist in future application cycles, further study about the impact of residency social media use on recruitment and applicant decision-making as well as effective strategies, is needed.
Auras of Detection: Power and Knowledge in Drug Prohibition:

Drug checking is an evidence-based strategy for overdose prevention that continues to operate (where it operates) in a legal “gray zone” due to the legal classification of some drug checking tools ...
Narrative Pasts: the making of a Muslim community in Gujarat, c. 1400–1650

In the conventional historiography of South Asia, the fifteenth century is often overlooked as a period of transition between two pan-Indian empires: the Delhi Sultanate and the Mughals. The crucia...
"It is the One Thing that has Worked": facilitators and barriers to switching to nicotine salt pod system e-cigarettes among African American and Latinx people who smoke: a content analysis.

Background Electronic cigarettes are a harm reduction strategy for individuals who smoke cigarettes who cannot or do not want to quit using FDA-approved cessation methods. Identifying perceived facilitators and barriers to switching among people who smoke cigarettes is critical to optimizing health impact. This is particularly important for the most dominant e-cigarette device, nicotine salt pod electronic cigarettes. We investigate the experience using pod electronic cigarettes among African American and Latinx individuals who smoke, the two largest racial/ethnic minority groups who experience significant health disparities. Methods From July 2018 to May 2019, adults who smoked cigarettes, age 21 + (N = 114; M age = 44.6, 59.6% male, 52.6% African American from Kansas City, 47.4% Latinx from San Diego) received JUUL-brand electronic cigarettes (referred to hereafter as JUUL) for 6 weeks and answered interview questions at week six. We inquired what they liked and disliked about using JUUL, what helped with switching and made switching difficult, future intentions for continued JUUL use, and how JUUL compared to past smoking reduction methods. Responses were coded into themes by independent raters. Theme frequencies were analyzed separately by race/ethnicity and week 6 use trajectory (exclusive JUUL use, dual JUUL and cigarette use, exclusive cigarette use). Results Clean/smell was the aspect of using JUUL most commonly liked (23%), followed by convenience (19%). Coughing/harshness was a more common barrier to switching for African American (44%) than Latinx (9%), and for continuing cigarette use (56%) than for those who exclusively switched or dually used JUUL and combustible cigarettes (15-21%). Most (78% African American; 90% Latinx) reported that the benefits of using JUUL outweighed barriers, and this varied by JUUL use trajectory: 94% exclusive switch, 86% dual use, and 42% continued cigarette use. The majority said they would continue using JUUL to replace cigarettes (83% African American; 94% Latinx) and that JUUL worked better than other methods to reduce cigarettes (72%). Conclusion African American and Latinx individuals who smoked experience using pod electronic cigarettes was generally positive. Understanding facilitators and impediments to switching to electronic cigarettes among racial/ethnic minority people who smoke can inform harm reduction interventions and reduce tobacco-related health disparities. Trial Registration ClinicalTrials.gov Identifier: NCT03511001 posted April 27, 2018.
Outcomes of a Presurgical Optimization Program for Elective Hernia Repairs Among High-risk Patients.

Importance Preoperative optimization is an important clinical strategy for reducing morbidity; however, nearly 25% of persons undergoing elective abdominal hernia repairs are not optimized with respect to weight or substance use. Although the preoperative period represents a unique opportunity to motivate patient health behavior changes, fear of emergent presentation and financial concerns are often cited as clinician barriers to optimization. Objective To evaluate the feasibility of evidence-based patient optimization before surgery by implementing a low-cost preoperative optimization clinic. Design, Setting, and Participants This quality improvement study was conducted 1 year after a preoperative optimization clinic was implemented for high-risk patients seeking elective hernia repair. The median (range) follow-up was 197 (39-378) days. A weekly preoperative optimization clinic was implemented in 2019 at a single academic center. Referral occurred for persons seeking elective hernia repair with a body mass index greater than or equal to 40, age 75 years or older, or active tobacco use. Data analysis was performed from February to July 2020. Exposures Enrolled patients were provided health resources and longitudinal multidisciplinary care. Main Outcomes and Measures The primary outcomes were safety and eligibility for surgery after participating in the optimization clinic. The hypothesis was that the optimization clinic could preoperatively mitigate patient risk factors, without increasing patient risk. Safety was defined as the occurrence of complications during participation in the optimization clinic. The secondary outcome metric centered on the financial impact of implementing the preoperative optimization program. Results Of the 165 patients enrolled in the optimization clinic, most were women (90 patients [54.5%]) and White (145 patients [87.9%]). The mean (SD) age was 59.4 (15.8) years. Patients’ eligibility for the clinic was distributed across high-risk criteria: 37.0% (61 patients) for weight, 26.1% (43 patients) for tobacco use, and 23.6% (39 patients) for age. Overall, 9.1% of persons (15 patients) were successfully optimized for surgery, and tobacco cessation was achieved in 13.8% of smokers (8 patients). The rate of hernia incarceration requiring emergent surgery was 3.0% (5 patients). Economic evaluation found increased operative yield from surgical clinics, with a 58% increase in hernia-attributed relative value units without altering surgeon workflow. Conclusions and Relevance In this quality improvement study, a hernia optimization clinic safely improved management of high-risk patients and increased operative yield for the institution. This represents an opportunity to create sustainable and scalable models that provide longitudinal care and optimize patients to improve outcomes of hernia repair.
Node Sensitivity Analysis Method for Power Quality Control of High Proportion Distributed Photovoltaic Access Distribution Network

Composite energy storage device is an effective method to solve series power quality problems caused by the excessive proportion of decentralized photovoltaic power generation incorporated into the distribution network, such as instantaneous power, voltage and harmonic pollution. A node sensitivity analysis method for power quality control of high-proportion distributed photovoltaic access distribution network is proposed, and the location and size of composite energy storage devices are quickly solved. Firstly, an optimization planning model for location and capacity of composite energy storage devices is established, which includes multi-objective optimization functions such as node voltage deviation, current total harmonic distortion rate and installation cost. Secondly, the sensitivity analysis method is used to preprocess all nodes to reduce the number of candidate nodes, and the feasible installation node alternative set of the composite energy accumulation device optimization planning model is obtained. In the process of using the improved multiobjective particle swarm optimization algorithm to solve the model, the amount of calculation is greatly reduced and the optimization efficiency is improved. Finally, taking IEEE 33 - bus distribution system as an example, the simulation results show the superiority of the node sensitivity analysis method.
Real-time Validation of a DC-link Tuning Method for an AC-AC Wind Converter in Fractional Frequency Transmission System

Wind power converters with modularity and scalability features paly pivotal role in interfacing of wind farms with the medium/high-power systems. These offshore or onshore grids are vulnerable to instabilities during certain working conditions that adaptive control solutions could overcome some of those stability issues. Additionally, computational burden of existing control strategies, such as model predictive control (MPC) has caused implementation barriers. In this work, the operational performance of the Modular Multilevel Matrix Converter (M3C) is assessed to transmit power produced from offshore wind farm to interconnect with onshore AC grid. Small-signal impedance measurement-based stability analysis are not efficient to predict large-signal stability characteristics. The two-layer control design architecture is proposed to regulate the converter branch voltages and currents. The second-layer iterative controller is embedded into an integrated perturbation analysis and sequential quadratic programming (IP A-SQP) method for handling uncertainty and overcome instability issues arise from capacitor voltage fluctuations. The complete control scheme objectives are lowering sampling time, optimization of variable constraints, and offering adaptive damping to enhance stability margin. The outcomes are verified via Real-Time simulation study using OP AL-RT platform for a designed 9-level M3C conversion system functions with an equal or low operating frequency at the input or output AC grids.
The DnaX-binding Subunits δ′ and ψ Are Bound to γ and Not τ in the DNA Polymerase III Holoenzyme

Abstract The DnaX complex subassembly of the DNA polymerase III holoenzyme is comprised of the DnaX proteins τ and γ and the auxiliary subunits δ, δ′, χ, and ψ, which together load the β processivity factor onto primed DNA in an ATP-dependent reaction. δ′ and ψ bind directly to DnaX whereas δ and χ bind to δ′ and ψ, respectively (Onrust, R., Finkelstein, J., Naktinis, V., Turner, J., Fang, L., and O'Donnell, M. (1995) J. Biol. Chem. 270, 13348–13357). Until now, it has been unclear which DnaX protein, τ or γ, in holoenzyme binds the auxiliary subunits δ, δ′, χ,and ψ. Treatment of purified holoenzyme with the homobifunctional cross-linker bis(sulfosuccinimidyl)suberate produces covalently cross-linked γ-δ′ and γ-ψ complexes identified by Western blot analysis. Immunodetection of cross-linked species with anti-δ′ and anti-ψ antibodies revealed that no τ-δ′ or τ-ψ cross-links had formed, suggesting that the δ′ and ψ subunits reside only on γ within holoenzyme.
Traversées francophones : littérature engagée, quête de l’oralité et création romanesque

La litterature francophone d’Afrique et des Antilles emerge dans un projet de contestation de la situation de domination qui a cree ses conditions de possibilites. Le discours critique va faire de l’engagement un critere de legitimation presque incontournable dans le champ litteraire africain et antillais. L’engagement etant presque toujours evalue a partir des prises de position et des declarations des ecrivains, on en arrive a une saturation du champ de la critique par un personnage omniscient. Face a cette surevaluation de l’auteur, qui fonde la tentation du charismatique, il s’agit ici, sans contester la place centrale de l’auteur dans le dispositif litteraire, de recentrer le concept d’engagement au coeur meme de la textualite. La conscience des conditions de naissance de l’ecriture francophone, de l’oralite destabilisee a l’ecriture contrainte, fait du texte un lieu exemplaire de manifestation de la traversee qui signale autant la genealogie esthetique que la passionnante inscription de la litterature dans le combat des peuples en quete de leur dignite.
A high-bandwidth high-power inverter

This paper presents experimental results for the design of a high power voltage fed inverter and discusses the benefits of two technologies used in its implementation. The inverter design presented here finds application in procedures requiring accurate control of large fast-varying currents with minimal error. In the context of a 1 MVA voltage fed inverter, we experimentally demonstrate the advantages of combining high performance power modules with advanced cooling technologies. The power devices used combine conventional Silicon IGBT's with Silicon Carbide Schottky antiparallel diodes dramatically reducing switching losses in the system.
Abstract 12: Bclxl is a key regulator of mitochondria-induced apoptosis in ovarian cancer stem cells

Proceedings: AACR 106th Annual Meeting 2015; April 18-22, 2015; Philadelphia, PA Background: Resistance to mitochondria-initiated apoptosis is a hallmark of chemoresistant cancer stem cells. As such, in epithelial ovarian cancer (EOC), EOC stem cells exhibit cross- resistance to a broad range of chemotherapy agents irrespective of their upstream targets. Members of the Bcl2 family of proteins function as rheostats of mitochondrial stability. Pro-apoptotic members Bak and Bax can form high molecular weight oligomers that allow the release of cytochrome c to the cytoplasm and consequently activating the caspases. In turn, pro-survival members such Bclxl and Bcl2 bind Bak and Bax thus preventing their oligomerization and maintaining mitochondrial integrity. We hypothesize that a distinct and targetable subset of Bcl2 proteins may be regulating the chemoresistant EOC stem cells. Methods: Whole cell lysates and cytoplasmic/mitochondrial fractions were collected from pure clones of chemoresistant CD44+/MyD88+ and chemosensitive CD44-/MyD88- EOC cells. Expression of proteins in the Bcl2 family was determined by western blot and net intensity of regions of interest (ROI) was determined to provide quantitative measure. Mitochondrial membrane potential (MMP) was measured using Mitotracker Red, caspase activity was quantified by Celltiter GloTM, and Bclxl expression was knocked-down in the EOC stem cells using siRNA. Results: We observed a differential expression profile of Bcl2 family members between the chemoresistant CD44+/MyD88+ and chemosensitive CD44-/MyD88- EOC cells. Using whole cell lysates, chemoresistant CD44+/MyD88+ EOC stem cells surprisingly express 3-fold and 5-fold more of the pro-death proteins Bak and Bax, respectively compared to the chemosensitive CD44-/MyD88- EOC cells. In addition, the EOC stem cells express 6 -fold more Bclxl but 5-fold less Bcl2 than CD44-/MyD88- EOC cells. At the level of the mitochondria, the significantly higher levels of Bak, Bax, and Bclxl are maintained in the EOC stem cells. Interestingly, as little as 14% knock-down of Bclxl in the EOC stem cells was able to induce loss of MMP, 3-fold increase in caspase-9 and 17-fold increase in caspase 3/7. Conclusion: Ovarian cancer stem cells have a unique mitochondrial phenotype and Bclxl is a key regulator of its stability and may play a role in resistance to chemotherapy-induced apoptosis. Targeting Bclxl may be an approach to complement current standard of care in ovarian cancer. The demonstration that apoptosis can be fully induced with minimal loss of Bclxl suggests an acceptable therapeutic window for Bclxl inhibitors. Citation Format: Ayesha B. Alvero, Mary Pitruzello, Michele Montagna, Eydis Lima, Gil Mor. Bclxl is a key regulator of mitochondria-induced apoptosis in ovarian cancer stem cells. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 12. doi:10.1158/1538-7445.AM2015-12
The blood supply of the rat mandible

The blood supply of the rat mandible was studied in 12 adult animals using four techniques. Eight animals were injected with a cinnabar, mercury, zinc oxide mixture (Teichmann's paste) for dissection and for cleared specimens, two with radiopaque material, and two others with India ink. Findings indicate that the coronoid, condylar, and angular processes of the mandible are supplied by vessels which are primarily concerned with the nutrition of the muscles that attach to these areas, and not from the inferior alveolar artery. The inferior alveolar artery supplies the body of the mandible, teeth and adjacent structures. After entering the mandibular foramen this artery bifurcates beneath the third molar tooth. The larger inferior stem passes downward and backward to supply multiple branches to the pulp of incisor tooth and branches to the periodontium about this tooth. The superior stem passes forward beneath the apices of the molar teeth to supply them and the adjacent tissue. The venous drainage of the bone varies – the coronoid and condylar processes drain downward into a confluence of venous channels about the apex of the incisor tooth. Veins of the molar teeth and supporting structures pass through the bone into gingival veins. Concentrations of venous channels primarily draining the angle and condyle are found along the inferior border of the angle and above, where the angular process joins the body proper.
SU-E-T-40: A Method for Improving Dose Gradient for Robotic Radiosurgery

Purpose: For targets with substantial volume, collimators of relatively large sizes are usually selected to minimize the treatment time in robotic radiosurgery. Their large penumbrae may adversely affect the dose gradient around the target. In this study, we implement and evaluate an inner-shell planning method to increase the dose gradient. Methods: Ten patients previously treated with CyberKnife M6 system were randomly selected with the only criteria that PTV be larger than 2cm3. A new plan was generated for each patient, in which the PTV was split into two regions: an inner shell and a core, where the core was created by shrinking the PTV by 5mm using 3D erosion, and the shell was obtained by subtracting the core from the PTV; then a 7.5mm Iris collimator was exclusively applied to the shell, with other appropriate collimators applied to the core depending on its size. The optimization objective functions and constraints were kept the same as the corresponding clinical plans. The results were analyzed for V12Gy, V9Gy, V5Gy, and gradient index (GI). Results: Volume reduction is found for the inner-shell method at all studied dose levels as compared to the clinical plans. The absolute dose volume reduction ranged from 0.05cm3 to 18.5cm3 with a mean of 5.6cm3 for 12Gy, from 0.2cm3 to 38.1cm3 with a mean of 9.8cm3 for 9Gy, and from 1.5cm3 to 115.7cm3 with a mean of 24.8cm3 for 5Gy, respectively. The relative GI reduction ranged from 3.2% to 23.6%, with a mean of 12.6%. Paired t-test for GI has a p-value of 0.0014. The range for treatment time increase is from −3 min to 20 min, with a mean of 7.0 min. Conclusion: The inner-shell planning method can significantly increase the dose gradient outside the PTV, while maintaining good coverage, conformity, and reasonable treatment time.
The stem cell marker (ABCG2) enhances hypoxic cell survival through interactions with heme

Proc Amer Assoc Cancer Res, Volume 45, 2004 517 Our results indicate that the ABC transporter and stem/progenitor cell marker, Bcrp/Abcg2 provides a survival advantage under hypoxic conditions, a function that is directly linked to heme biosynthesis. We demonstrate that under hypoxia, progenitor cells from Bcrp-/- mice have reduced ability to form colonies compared to progenitor cells from Bcrp+/+ mice. Blocking Bcrp function in Bcrp+/+ progenitor cells markedly reduces survival under hypoxic conditions. However, blocking heme/porphyrin biosynthesis reverses the hypoxic susceptibility of Bcrp-/- progenitor cells, a finding indicating heme/porphyrins are detrimental to Bcrp-/- progenitor cell survival. Mechanistically, we find that cells overexpressing Bcrp accumulate lower amounts of porphyrin and that Bcrp specifically binds heme. Finally, Bcrp expression is regulated by hypoxia through interaction with the hypoxia response elements in the Bcrp promoter a finding that suggests cells can, upon demand, reduce excess heme/porphyrin accumulation which can be detrimental to cells due to the generation of reactive oxygen species. These studies imply that Bcrp permits enhanced cell survival in oxygen poor environments by reducing the accumulation of toxic heme metabolites. These findings have important implications for the chemotherapeutic treatment of solid tumors, the drug resistance of which may be attributable to a hypoxic environment.
Specific glucocorticoid binding in human uterine tissues, placenta and fetal membranes

Abstract The binding of [ 3 H]dexamethasone to cytosol fractions of human myometrium, endometrium, decidua, chorion, amnion and placenta has been studied. All tissues examined contained high affinity, low capacity binding sites with high specificity for glucocorticoids. Maximum specific binding of [ 3 H]dexamethasone was reached after about 10 h at 0–4°C and remained stable for at least the next 12 h. Sucrose density gradient analysis showed that the binding macromolecules sedimented at 7.9 S in hypotonie solutions and at 4.35 in solutions containing 0.4 M KCl. In the presence of sodium molybdate, the sedimentation coefficients shifted both in the absence and presence of 0.4 M KCl to 8.9 and 5.7 S, respectively. The apparent equilibrium dissociation constants ( K d ) of the glucocorticoid binding sites were similar in most tissues, ranging between 1 and 6 nM, with the exception of the placenta in which the binding sites showed a higher K d (13–22nM). In all tissues studied, the binding affinities were similar in nonpregnant and pregnant patients and in patients at different stages of pregnancy or in labor. The concentration of the binding sites in the different tissues ranged from 11 to 268 fmol/mg protein, higher concentrations being found in myometrium, placenta and amnion and lower concentrations found in endometrium, chorion and decidua. The number of binding sites was higher in the myometrium of nonpregnant than pregnant women, but was similar in the myometrium of women at term pregnancy before or during labor. In the placenta, the number of binding sites increased significantly from early pregnancy to midpregnancy, while in chorion, amnion and decidua the number of binding sites did not change during pregnancy. It is concluded that human uterine tissues, placenta and fetal membranes contain specific binding sites with properties characteristic of glucocorticoid receptors suggesting that these tissues may respond directly to glucocorticoids.
Effects of annealing atmosphere on the luminescent efficiency of ZnTe:O phosphors

Abstract The effect of the annealing atmosphere on the luminescent efficiency of ZnTe:O phosphors for X-ray imaging applications was studied. The phosphors were doped by ball-milling bulk ZnTe crystals in an O2 atmosphere and annealed in various atmospheres: vacuum, N2 or forming gas (95%N2/5%H2). All samples exhibited a deep red emission centered at 680 nm.The samples annealed in forming gas atmosphere exhibited an X-ray luminescent efficiency five times higher than the samples annealed in vacuum or N2 atmospheres, which was attributed to the removal of surface tellurium oxides.
Intradermal Test in American Leishmaniasis with a Polysaccharide Fraction Isolated from Leishmania Brasilensis1

The demonstration of the existence of a specific cutaneous hypersensitivity in leishmaniasis was originally made by Wagener (1) and by Wagener and Koch (2) who obtained positive cutaneous reactions with alkaline extracts of Leish-mania tropica and of Leishmania infantum ( = L. donovani) in rabbits previously inoculated with dead culture forms of these flagellates.
Surface enhanced raman and resonance raman spectroscopy in a non-aqueous electrochemical environment: Tris(2,2′-bipyridine)ruthenium(II) adsorbed on silver from acetonitrile

Abstract This letter reports the first observation of both surface enhanced Raman scattering (SERS) and surface enhanced resonance Raman scattering (SERRS) from the transition metal complex tris(2,2′-bipyridine)ruthenium (II), Ru(bpy) 3 2+ , adsorbed on a silver electrode from acetonitrile (ACN). The assignment of these spectra as valid examples of SERS and SERRS in a non-aqueous environment is based on the following criteria: (1) in situ demonstration of monolayer surface coverage of Ru(bpy) 3 2+ using double potential step chronocoulometry (DPSCC); (2) the Raman signals are most intense after surface roughening by anodization; (3) the Raman spectra are potential dependent in the non-faradaic potential region; (4) the measured enhancement factors are greater ilian 10 6 ; (5) the surface spectra are frequency shifted relative to their bulk counterpart; and (6) several other molecules also exhibit non-aqueous SERS and SERRS behavior. These results are highly significant in that generality of surface enhanced Raman spectroscopy has been extended into the rich domain of nonaqueous electrochemistry.
Cosmic radiation: Constraints on space exploration

Abstract The hazard from cosmic radiation is examined using present cosmic ray models and the current definition of the quality factor. Current crew exposure limits are also assumed. Cosmic radiation is found to place strong constraints on manned missions to Mars. A workshop to discuss new measurements and models of galactic cosmic ray fluxes was held in August 1991. The motivation for the workshop will be explained by describing how galactic cosmic radiation constraints plans for manned space exploration and why an accurate knowledge of the absolute cosmic ray fluxes is needed to plan a manned mission to Mars.
Chemokine receptor expression in cultured glia and rat experimental allergic encephalomyelitis

Abstract Chemokines are a group of pro-inflammatory peptides that mediate leukocyte migration and activation. Several members of the chemokine family have been shown to be synthesized by cells of the central nervous system (CNS). To begin to address the role of chemokine receptors in CNS physiology, we identified, by molecular cloning techniques, the rat orthologs of the chemokine receptors, CCR2, CCR3, CCR5, and CXCR4. CCR2 and CCR5 expression was detected in rat spleen, lung, kidney, thymus and macrophages; CCR5 mRNA was also detected in rat brain. Primary cultures of rat microglia expressed CCR5 mRNA that was regulated by IFN- γ , while both cultured astrocytes and microglia were found to contain mRNA for CXCR4 and CX 3 CR1. Induction of experimental allergic encephalomyelitis (EAE) in the rat was accompanied by increased levels of CCR2, CCR5, CXCR4, and CX 3 CR1 mRNAs in the lumbar spinal cords of animals displaying clinical signs of the disease. These data identify the rat orthologs of chemokine receptors and demonstrate that brain, spinal cord, and cultured glial cells express chemokine receptors that can be regulated both in vitro and in vivo.
Calcium carbonate films and helices grown in solutions of poly(aspartate)

Addition of charged polypeptides, in particular poly(aspartate), to supersaturated solutions of calcium carbonate (CaCO_3) leads to unusual morphologies in the inorganic phase. The polymer causes deposition of CaCO_3 films, which appear to act as membranous substrates that mediate the growth of CaCO_3 crystals. Spherulitic vaterite aggregates with helical extensions, and distorted calcite crystals that contain spiral pits, have been produced. A correlation has been noted between the structures of the crystalline films and those of the crystal aggregates associated with them: i.e. films of spherulitic texture yield electron diffraction patterns characteristic of vaterite and support the growth of spherulitic vaterite aggregates whereas calcitic single-crystal mosaic films carry rhombohedral calicite crystals. These films and aggregates exhibit features reminiscent of the morphologies observed in biogenic minerals.
The Electric Field Produced by an Eccentric Dipole in a Homogeneous Circular Conducting Lamina

In a manner essentially similar to that adopted by Helmholtz and particularized by F. N. Wilson and R. H. Bayley for the solution of the potential of the arbitrary dipole in the homogeneous spherical conductor, the corresponding solution is developed for an arbitrary dipole potential in and on the boundary of a homogeneous circular plane lamina. The formulas for the latter solution are simple when compared with those for the sphere, and should therefore prove useful in testing measuring circuits and lead methods before attacking clinical electrocardiographic problems. A table is computed for positions of the zero of potential on the boundary, using 15 equal increases of dipole eccentricity both for the circular plane lamina and for the sphere.
Helix-coil transitions of compositionally heterogeneous DNA.

Fragmented and mitomycin C cross-linked E. coli DNA was fractionated according to base composition by means of hydroxylapatite chromatography and density-gradient centrifugation in order to determine the effect of compositional heterogeneity on the breadth of the helix–coil transition. The transitions of some of the fractions are broader than that of the unfractionated DNA, due, presumably, to nonrandom sequences in molecules of 5 × 105 daltons. Analysis of the transition breadths in terms of the known heterogeneity leads to reconsideration of current DNA helix–coil transition theory. We propose that partially denatured states include those for which the chains do not remain in strict register. Denaturation profiles are comprehensible only if this multitude of entropically favorable, degenerate states is included in the theory.
The Contribution of Nonaneurysmal Intracranial Hemorrhage to Stroke Mortality in New York City Blacks

Of 527 unselected stroke patients (98% black) in a city hospital, 80 (17%) had nonaneurysmal intracranial hemorrhages, with a fatality rate of 85%. Of 216 inhospital deaths 37% were due to such hemorrhages. In patients aged 65 and less, 52% of 90 fatal events were hemorrhagic. Only in patients below age 46, however, did cerebral hemorrhage account for more deaths than infarction. The incidence of hemorrhage and the proportion of inhospital deaths from it were higher than in three white American and lower than in one black African series. The differences were not major, and could be explained by varying definitions and hospital use. The mean age of patients with fatal hemorrhage was 61 years. When the inhospital mortality is extrapolated into annual mortality estimates, the following conclusions may be drawn about spontaneous nonaneurysmal intracranial hemorrhage in New York City blacks: (1) above age 45, it does not account for more deaths than infarction, (2) it is not much more common or more lethal in blacks than in whites, and (3) it does not occur more predominantly at earlier ages in blacks than in whites.
3-phosphoglyceric acid as a hill oxidant, without CO2 fixation, in mesophyll cells isolated from Digitaria sanguinalis (L.) scop., A C4 plant

Abstract Mesophyll cells isolated from leaves of the C4 plant, Digitaria sanguinalis, are capable of utilizing 3-phosphoglyceric acid as a Hill oxidant. The resulting O2 evolution depends on light and is inhibited by 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU), uncouplers, and iodoacetate. It is believed that the photosynthetic production of NADPH is coupled to the reduction of 1,3-diposphoglyceric acid (1,3-DPGA) catalyzed by glyceraldehyde-3-phosphate (G-3P) dehydrogenase. No CO2 fixation could be demonstrated concurrent with these reactions.
Unilateral Divorce, the Decreasing Gender Gap, and Married Women's Labor Force Participation †

Married women's labor force participation (LFP) increased dramatically in the United States between the 1940 and 1960 cohort. The two cohorts lived under different divorce regimes (unilateral divorce rather than mutual consent). The 1960 cohort also had a lower gender wage gap. We use a quantitative dynamic life-cycle model of endogenous marital status, calibrated to key statistics for the 1940 cohort, to study the effects of these two changes. We find that both drivers combined are able to account for over 50 percent of the increase in married women's LFP and also generate large movements in marriage and divorce rates.
Transferable dynamic stock rights

Abstract Individual transferable quotas (ITQs), while solving many short-run externalities, provide limited incentives for individual fishers to conserve the resource. All decisions that determine harvests are made by the government, and the shares of future harvests that are allocated to any particular fisher are not affected by that fisher's actions. For example, there is no incentive for the individual fisher to avoid catches of smaller fish. In fact, the incentives for discarding and high-grading may be worse under ITQs than under other forms of management. This analysis proposes a ‘transferable dynamic stock right’ (TDSR), under which rights are allocated to fishers as life-cycle shares of each year-class that can be harvested. Year-class allocations would change each year to reflect catches, growth and natural mortality. Allocations of newly-recruited fish would be in proportion to the share of the rights to the breeding stock held by each fisher. Under TDSRs, the fisher would internalize the economic decision about whether to catch a given year-class as small fish or as a larger tonnage of large fish. TDSRs provide the fisher with incentives to harvest in ways that maximize the value of the catch from a given year-class.
Systemic animal external parasiticidal activity of perfluoroalkylbenzimidazoles and their aminoanilide precursors

In vitro and in vivo efficacy data indicate that chemical activity is optimized at the 2 carbon chain length and that these compounds have injectable potency and spectrum of activity against major animal external parasite species.
Mueller matrix optical imaging with application to tissue diagnostics

In this paper we present experimental results demonstrating processing techniques developed in our laboratory that can be utilized to decode or extract useful information from two-dimensional Mueller matrices of turbid media. Through the use of these methods, involving the partial least squares technique, it is shown how scattering coefficient contributions as a function of particle size can be estimated for a given sample. Furthermore, we demonstrate how a spatial selection algorithm known as "chain select" can be used to help facilitate the interpretation of the measured Mueller matrix images. The samples utilized in this investigation were comprised of polystyrene spheres with diameters ranging from 200 nm to 2000 nm and analyzed with 514 nm light. At this wavelength, both Rayleigh and Mie-types of scattering are observed.
Transcription factor Foxp3 and its protein partners form a complex regulatory network

The transcription factor Foxp3 is indispensible for the differentiation and function of regulatory T cells (T(reg) cells). To gain insights into the molecular mechanisms of Foxp3-mediated gene expression, we purified Foxp3 complexes and explored their composition. Biochemical and mass-spectrometric analyses revealed that Foxp3 forms multiprotein complexes of 400-800 kDa or larger and identified 361 associated proteins, ∼30% of which were transcription related. Foxp3 directly regulated expression of a large proportion of the genes encoding its cofactors. Some transcription factor partners of Foxp3 facilitated its expression. Functional analysis of the cooperation of Foxp3 with one such partner, GATA-3, provided additional evidence for a network of transcriptional regulation afforded by Foxp3 and its associates to control distinct aspects of T(reg) cell biology.
Generalizing the N=2 supersymmetric RG flow solution of IIB supergravity

Abstract We explicitly construct the supersymmetry transformations for the N =2 supersymmetric RG flow solution of chiral IIB supergravity. We show that the metric, dilaton/axion, five-index tensor and half of the three index tensor are determined algebraically in terms of the Killing spinor of the unbroken supersymmetry. The algebraic nature of the solution allows us to generalize this construction to a new class of N =2 supersymmetric solutions of IIB supergravity. Each solution in this class is algebraically determined by supersymmetry and is parametrized by a single function of two variables that satisfies a non-linear equation akin to the Laplace equation on the space transverse to the brane.
A comparison of salt and water regulation in California quail (Lophortyx californicus) and Gambel's quail (Lophortyx gambelii)

Abstract 1. 1. The relative abilities in water conservation of Gambel's quail, a desert species, and California quail, a closely related non-desert species, were compared. 2. 2. Gambel's quail could maintain body weight on higher concentrations of sea water (62·5%) and NaCl solutions (0·45 M) than California quail (50% sea water and 0·30 M NaCl). 3. 3. Gambel's quail produced a significantly more concentrated urine than California quail when they were drinking NaCl solutions. 4. 4. During heat stress Gambel's quail reduced locomotor activity and California quail increased it. The reduction of activity under heat stress exhibited by Gambel's quail might enable them to require less water per day than California quail at high ambient temperatures. 5. 5. The slightly better ability of Gambel's quail to cope physiologically and behaviorally with conditions found in arid regions helps to explain the differences in preferred habitat observed for the two species.