cssi/SciSciGPT-SciSciNet huggingface dataset:
Mechanisms of action of radiotherapy and chemotherapeutic adjuvants. A review.

A review of the rationale for application of combined radiation and chemotherapy in the treatment of certain malignant tumors has been presented. The mechanisms of action of ionizing radiations and many of the commonly employed chemotherapeutic agents are intimately related to the nucleic acid metabolism of proliferating cells. Modification of the DNA-molecule by certain chemotherapeutic agents results in sensitization of the cell to subsequent irradiation. Reduction in the total number of malignant cells by preirradiation chemotherapy facilitates subsequent radiotherapy of advanced tumors. Certain chemotherapeutic antitumor agents exert a beneficial effect by restraining the growth of distant metastases which often escape clinical detection.
Robustness of genetic algorithm solutions in resource leveling

Algorithms for solving the resource leveling problem (RLP) in construction projects are proven to increase efficiency, create predictability, and balance demand across adjacent time periods or the project's duration while observing time and resource constraints. Leveling resources reduces the amount of change between one time period and the next in the project’s resource usage. Conventional optimization methods of the RLP can become difficult as the problem size grows, because the solution space grows exponentially as decision variables are added. Genetic algorithms are very capable when applied to large-scale instances of the RLP, and here the author applies a genetic algorithm testing multiple objective functions in literature with different performance measures. Results show that given a large problem, genetic algorithms capably produce a range of options for stakeholders and decision-makers and highlight changes in resource while preserving the strength of the solution.
The effect of Evercare on hospital use.

Objectives: To examine the use of hospital and related medical care services of a novel managed care program using nurse practitioners (NPs) and directed specifically at long-stay nursing home residents. Design: Quasi-experimental posttest design with two control groups to minimize selection bias. Setting: Nursing homes. Participants: Evercare enrollees in five sites were compared with two sets of controls: nursing home residents in the same nursing homes who did not enroll in Evercare (control-in) and residents of nursing homes that did not participate in Evercare (control-out). Measurements: Utilization data from Medicare and United Healthcare (the parent corporation for Evercare) were obtained for slightly more than 2 years. Patterns of use were assessed by calculating the monthly use rate for each group and aggregating to form annual rates. Usages addressed included hospital admissions and days, emergency room visits, therapy services, mental health services, and podiatry. Adjustments were made to correct for age, race, and sex. Because the groups differed in terms of the rate of cognitive impairment, the analysis was stratified on this variable. Results: The incidence of hospitalizations was twice as high in control residents as in Evercare residents (4.63 and 4.67 per 100 enrollees per month vs 2.43 in the 15 months after census, P<.001). This difference corresponded to Evercare's use of intensive service days. The same pattern held for preventable hospitalizations (0.80 and 0.86 vs 0.28, P<.001). The pattern held when residents were stratified by cognitive status. On average, using a NP is estimated to save about $103,000 a year in hospital costs per NP. Conclusion: The use of active primary care provided by NPs may have prevented the occurrence of some hospitalizable events, but its major effect was allowing cases to be managed more cost-effectively.
The Climatic Aftermath

The eruption of Mount Pinatubo on 15 June 1991 produced the largest stratospheric volcanic aerosol cloud of the 20th century. About 20 megatons of SO2 was injected into the stratosphere, affecting global climate for years. In his Perspective, Robock discusses the climatic lessons learned from the Pinatubo eruption. An accompanying Perspective by Newhall et al . discusses the geologic insights gained from the eruption.
Hydrolytic Enzymes in KB Cells Infected with Poliovirus and Herpes Simplex Virus

Flanagan, John F. (Duke University School of Medicine, Durham. N.C.). Hydrolytic enzymes in KB cells infected with poliovirus and herpes simplex virus. J. Bacteriol. 91:789–797. 1966.—The effect of poliovirus and herpes simplex virus infection on the activity of five hydrolytic enzymes was studied in tissue culture cells of KB type. During the course of poliovirus infection, the activity of β-glucuronidase, acid protease, acid ribonuclease, acid deoxyribonuclease, and acid phosphatase in the cytoplasm rose to levels two- to fourfold greater than the activity present in the cytoplasm of uninfected cells. The rise in cytoplasmic activity was accompanied by a concomitant decrease in enzymatic activity bound to cell particles. Shift of enzymatic activity from the particulate to soluble state was first detected at 6 hr after poliovirus infection, coinciding with the appearance of new infectious particles and virus cytopathic effect. No net synthesis of these enzymes after poliovirus infection was found. Hydrocortisone added to the culture medium failed to affect either the titer of virus produced in the cells or the release of hydrolytic enzymes from the particulate state. Herpes simplex infection produced minimal alterations in the state of these enzymes in KB cells. It is hypothesized that the breakdown of lysosomes and release of hydrolytic enzymes accompanying poliovirus infection is produced by alterations in cell membrane permeability during the course of virus replication and by the consequent change in the ionic content of the cell sap.
Impacts of Global Christian Engagement on Economic Development vis-a-vis Human Trafficking Elimination Efforts

Christians have engaged in economic development projects ever since the early days of the colonial period. The gap between religion and economics has only increased over time as groups from both fields are guilty of distancing themselves and their work from the categorical “other.” Such a tendency perpetuates mutual misunderstandings of the opposite members’ motivations for involvement in economic enterprises. We have seen an unprecedented response of NGOs to global issues such as poverty and human trafficking, however these problems are too big for organizations to attempt to tackle alone or unilaterally. Now more than ever, there is a need for multiparty communication, coordination, cooperation and collaboration efforts between faith-based organizations and their secular counterparts. This paper argues that current trends toward global economic development are a direct result of earlier Christian colonial missions, thus religious rhetoric is a constitutive element of contemporary discourses on development. This paper pays particular attention to faith dialogues and interfaith commitments--or lack thereof--regarding anti-trafficking initiatives worldwide.
TWave: high-order analysis of spatiotemporal data

Recent advances in data acquisition and sharing have made available large quantities of complex data in which features may have complex interrelationships or may not be scalar. For such datasets, the traditional matrix model is no longer appropriate and may fail to capture relationships between features or fail to discover the underlying concepts that features represent. These datasets are better modeled using tensors, which are high-order generalizations of matrices. However, naive tensor algorithms suffer from poor efficiency and may fail to consider spatiotemporal neighborhood relationships in analysis. To surmount these difficulties, we propose TWave, a wavelet and tensor-based methodology for automatic summarization, classification, concept discovery, clustering, and compression of complex datasets. We also derive TWaveCluster, a novel high-order clustering approach based on WaveCluster, and compare our approach against WaveCluster and k-means. The efficiency of our method is competitive with WaveCluster and significantly outperforms k-means. TWave consistently outperformed competitors in both speed and accuracy on a 9.3 GB medical imaging dataset. Our results suggest that a combined wavelet and tensor approach such as TWave may be successfully employed in the analysis of complex high-order datasets.
Injection of Soluble Antigen into the Anterior Chamber of the Eye Induces Expansion and Functional Unresponsiveness of Antigen-Specific CD8+ T Cells

The injection of soluble Ag into the anterior chamber (a.c.) of the eye induces systemic tolerance, termed a.c.-associated immune deviation (ACAID), characterized by Ag-specific inhibition of delayed-type hypersensitivity responses and a reduction in complement-fixing Abs. Recently, we have shown that CD8(+) CTL responses are also inhibited in ACAID. In this study, we have used an adoptive transfer approach to follow the fate of Ag-specific CD8(+) TCR transgenic (OT-I) T cells in vivo during the induction and expression of ACAID. C57BL/6 (B6) recipients of OT-I splenocytes that were injected with chicken OVA in the a.c. displayed reduced OVA-specific delayed-type hypersensitivity and CTL responses, compared with those of mice given OVA in the subconjunctiva or an irrelevant Ag human IgG in the a.c. OT-I T cells increased 9-fold in the submandibular lymph nodes and 3-fold in the spleen following an a.c. injection with OVA, indicating that expansion rather than deletion of Ag-specific CD8(+) T cells was induced by this treatment. OT-I T cells expanded equivalently upon administration of OVA in CFA to mice previously given OVA in the a.c. or subconjunctiva. However, the lytic activity attributed to OT-I T cells was reduced on a per-cell basis in mice previously given OVA in the a.c. We conclude that tolerance of CTL responses in mice given Ag via the a.c. results from unresponsiveness of Ag-specific CD8(+) T cells.
A bistatic measurement technique for characterization of the effective dielectric constant of random media using a monostatic radar

A new technique for measuring the effective dielectric constant of dense random media is presented. In this technique, the mean bistatic scattered fields of a cluster of random media, confined in a geometrical boundary, are measured using a monostatic radar and a rotatable ground plane and fitted to the bistatic scattered fields of a homogeneous lossy material with the same geometrical boundary. The accuracy of the bistatic measurement technique is verified by measuring the bistatic response of a number of canonical targets with known theoretical responses. The ability of the new technique in estimating the effective dielectric constant of a cluster of dense random media is demonstrated.
Caspase-2 redux

It has been difficult to assign caspase-2 to the effector or initiator caspase groups. It bears sequence homology to initiators (caspase-9 and CED-3), but its cleavage specificity is closer to the effectors (caspase-3 and -7). Interest in caspase-2 was dampened by the lack of a dramatic phenotype in the caspase-2 null mouse. Studies have been inhibited by the lack of knowledge about its mechanism of activation and the lack of specific methods to assay its activity. Molecular studies have defined a unique role for caspase-2 in apoptosis initiated by beta-amyloid toxicity or by trophic factor deprivation. Recently, a role for caspase-2 as an upstream initiator of mitochondrial permeabilization has been proposed. Thus, while much remains to be deciphered about caspase-2, most critically the mode of activation, it is clear that caspase-2 plays critical and singular roles in the control of programmed cell death.
Thermal desorption mass spectrometric and x-ray photoelectron studies of etched surfaces of polytetrafluoroethylene

Abstract The etching of polytetrafluoroethylene (PTFE) with Na solutions is known to lead to a loss of F, a loss which is correlated with enhanced adhesion. Subsequent heating partially restores surface F with a concurrent loss of adhesion strength. We have combined X-ray photoelectron spectroscopy (XPS) and gas phase mass spectroscopy for in situ measurements of the processes that occur as the fluorocarbon is heated. An array of volatile products, which vary with the specific treatment, desorb from etched PTFE. Among these are: N2 and low molecular weight fluorocarbons, the amounts of which monotonically decrease with increasing exposure to the etching solution (and probably result from the bulk); species such as CO and CO2, which in part result from surface impurities; and water and acetone which result from the rinse steps following the etching process. XPS measurements show that etching produces a major loss of surface F and a gain of surface O. The latter probably results from the subsequent rinse steps. Heating produces a substantial recovery in surface F with only a small decrease in the surface O, and the gain in surface F is shown to occur at a higher temperature than the desorption of any species from the surface. Thus, desorption of products from the surface is decoupled, in terms of both the distribution of products and their relative temperatures, from the surface changes as monitored by XPS. This decoupling suggests that the increase in surface F results from diffusion of low molecular weight fluorocarbons from the bulk or a transition region, or from a rearrangement of the sponge-like surface region produced in the etching process.
Coping in Healthy Primigravidae Pregnant Women

ABSTRACT Objective To describe coping in healthy pregnant women and examine sociodemographic factors associated with coping styles. Design A cross-sectional descriptive survey. Setting Childbirth classes at 2 Midwestern urban hospitals. Participants Healthy primigravidae ( N =159), ages 18 to 34, in their third trimester. Methods A cross-sectional, descriptive survey of healthy pregnant women using 2 reliable coping tools to measure pregnancy coping and general coping styles and determine their associations with sociodemographic factors. Results Prayer and task coping were the most frequently used coping styles; avoidance and emotion coping were used least frequently. Younger age was associated with greater use of preparation and distraction coping. Non-White race was associated with frequent use of prayer, task, and distraction coping. Education less than graduate school was associated with frequent use of preparation. Conclusion Healthy pregnant women used a variety of coping styles, and sociodemographic factors influenced them. Future research requires diverse samples to explore prayer in pregnancy and the influence of stress and other psychological factors on coping styles. Nurses have many opportunities to assess coping during pregnancy. Nurse-directed community-based programs that promote healthy coping can optimize maternal and newborn health.
Recommendations in location-based social networks: a survey

Recent advances in localization techniques have fundamentally enhanced social networking services, allowing users to share their locations and location-related contents, such as geo-tagged photos and notes. We refer to these social networks as location-based social networks (LBSNs). Location data bridges the gap between the physical and digital worlds and enables a deeper understanding of users' preferences and behavior. This addition of vast geo-spatial datasets has stimulated research into novel recommender systems that seek to facilitate users' travels and social interactions. In this paper, we offer a systematic review of this research, summarizing the contributions of individual efforts and exploring their relations. We discuss the new properties and challenges that location brings to recommender systems for LBSNs. We present a comprehensive survey analyzing 1) the data source used, 2) the methodology employed to generate a recommendation, and 3) the objective of the recommendation. We propose three taxonomies that partition the recommender systems according to the properties listed above. First, we categorize the recommender systems by the objective of the recommendation, which can include locations, users, activities, or social media. Second, we categorize the recommender systems by the methodologies employed, including content-based, link analysis-based, and collaborative filtering-based methodologies. Third, we categorize the systems by the data sources used, including user profiles, user online histories, and user location histories. For each category, we summarize the goals and contributions of each system and highlight the representative research effort. Further, we provide comparative analysis of the recommender systems within each category. Finally, we discuss the available data-sets and the popular methods used to evaluate the performance of recommender systems. Finally, we point out promising research topics for future work. This article presents a panorama of the recommender systems in location-based social networks with a balanced depth, facilitating research into this important research theme.
Expanding Discourse Options through Computer-Mediated Communication: Guiding Learners toward Autonomy

This article proposes a multiliteracies-based pedagogical framework for the analysis of computer-mediated discourse (CMD) in order to give students increased access to expanded discourse options that are available in online communication environments and communities (i.e., beyond the classroom). Through the analysis of excerpts and a corpus of French and Spanish electronic discourse, we illustrate how this framework can promote autonomous, lifelong participation and learning emphasized by the Communities component of the National Standards. Such an analysis allows students and instructors to explore similarities and divergences within and among different types of CMD and, by extension, more traditional types of discourse that are all shaped by technical and social affordances and constraints.
Shear Orientation of Nanoparticle Arrays Templated in a Thermoreversible Block Copolymer Micellar Crystal

The shear alignment of binary crystals of polymeric micelles and small particles is demonstrated using contrast-variation SANS experiments. The larger micelles form close-packed crystals that serve as a template to the smaller nanosized particles. The simultaneous alignment of the two phases, micelles and templated particles (silica or albumin proteins), is demonstrated from the scattering at two different contrast values. A new method to quantify the alignment of colloidal crystals using diffraction is also proposed. This method is used to probe the alignment of the crystals as a function of shear rate. It is found that the binary crystals align at significantly lower shear rates when compared to the neat micelle crystals. The diffraction profiles of the cocrystals are compared to models for the flow mechanism of colloidal crystals. Differences between the experimental profiles and the predictions suggest that there is a coexisting crystal phase that is not accounted for in the model.
One-pot catalytic conversion of cellulose and of woody biomass solids to liquid fuels.

Efficient methodologies for converting biomass solids to liquid fuels have the potential to reduce dependence on imported petroleum while easing the atmospheric carbon dioxide burden. Here, we report quantitative catalytic conversions of wood and cellulosic solids to liquid and gaseous products in a single stage reactor operating at 300–320 °C and 160–220 bar. Little or no char is formed during this process. The reaction medium is supercritical methanol (sc-MeOH) and the catalyst, a copper-doped porous metal oxide, is composed of earth-abundant materials. The major liquid product is a mixture of C2–C6 aliphatic alcohols and methylated derivatives thereof that are, in principle, suitable for applications as liquid fuels.
Simulation and Experimental Studies of Electrothermal Behaviors of Microwire Initiators for Fusing Applications

Microwire initiators enhance the output pressure and reduce the required input voltage for the explosives initiation in fusing applications due to large surface areas and high electrical and thermal conductivities. We investigated electrothermal behavior of Cu and Au microwires with diameters in the range of 25∼100 μm. Microwires with smaller diameter ignited quickly and required the lower input voltage to be ignited. A low impedance circuit was used in order to apply relatively low voltages but high current density to the initiator wire. We investigated the ignition process theoretically by combining an electric circuit model and a specific current action model related to phase changes. The theoretical calculations are in good agreement with the experimental observations in terms of the burst time and voltage rise profile.Copyright © 2010 by ASME
Indications and Appropriateness of Inferior Vena Cava Filter Placement

Abstract Background Several professional societies have published guidelines for the placement of inferior vena cava (IVC) filters. The authors wanted to determine how frequently patients in their hospital had IVC filters placed based on current indications and to compare guidelines published by the American College of Chest Physicians (ACCP) and the Society of Interventional Radiologists (SIR). Methods The authors performed a structured review of the medical records of 180 patients identified by International Classification of Diseases, Ninth Revision , codes who had IVC filter placement at their hospital between July 1, 2007, and June 30, 2012. Indications for placement were based on current recommendations from the ACCP and SIR. Results These patients had a mean age of 62.4 ± 15.7 years and included 96 men and 84 women. one hundred forty patients had a history of deep venous thrombosis, pulmonary emboli or both. one hundred seven patients had permanent filters inserted, 34 had retrievable filters inserted and 39 had an unknown type of filter inserted. Forty-one patients (22.7%) had no definite indication for IVC filter insertion based on SIR guidelines, and 72 (40%) had no definite indication based on ACCP guidelines. There was a good agreement between the ACCP guidelines and the SIR guidelines when indications were categorized. Only one retrievable filter was removed. Conclusions Twenty to forty percent of the patients with IVC filter insertions in their hospital had no definite indication documented in the medical record. A performance improvement activity to evaluate the use of IVC filters, such as a dedicated clinic, may be useful.
Prognostic staging system and therapeutic effectiveness for recurrent or chronic sinusitis in children.

Abstract Objective We sought to assess the clinical status of pediatric sinusitis patients after a minimum of 2 years follow-up and to evaluate relative treatment effectiveness. Study design We conducted a medical record review of 308 patients, with a 2-year follow-up questionnaire. Results Overall, 55% of children were “much improved.” A 4-stage prognostic system was developed and used to compare results in 133 patients who had not responded to medical treatment and who had positive sinus computed tomography scans. Endoscopic sinus surgery (ESS) had no apparent advantages in stages I and IV, but in stages II and III, rates of “much improved” for ESS versus medical therapy were 79% versus 54% and 68% versus 42%, respectively. Conclusion These results suggest that ESS may be particularly effective for patients from intermediate prognostic stages. Significance This type of prognostic staging and evaluation of treatment effectiveness is necessary and important in chronic sinusitis, where randomized trials are unlikely to be performed.
Differential understanding of sexual abuse prevention concepts among preschoolers

Most evaluations of sexual abuse prevention programs employ composite knowledge scores that may mask whether individual skills are differentially understood. The few studies examining separate skills have provided no statistical justification for doing so. This study attempted to validate empirically distinct prevention skills and whether children comprehend these skills in the order taught by prevention programs: RECOGNITION (of good and bad touch), SAY-NO (refuse the perpetrator), GO (leave the situation), TELL-WHO (find an adult), and TELL-WHAT (accurately disclose the abuse). Subjects were 117 preschoolers who were individually administered the "What If Situations Test" (WIST). Analyses confirmed that the WIST was composed of six skills. The hypothesized sequence of skills produced a high coefficient of reproducibility, but an even higher coefficient was obtained when three common sequence reversals were added to the existing logical sequences. We discuss explanations for these cognitive sequence reversals and applications of this information for teaching preschoolers prevention concepts.
Environmental enrichment and brain chromatin.

Twenty-eight-day-old Fischer rats were assigned to enriched, isolated, or standard environmental rearing for 60 days. Chromatin from cortex, cerebellum, and rest of brain was assayed for capacity to support in vitro RNA synthesis. No significant differences were observed across rearing groups. These results are compared to previous findings after shorter rearing intervals and are discussed in terms of a transient influence of the rearing environment on brain chromatin.
Reducing drug use, human immunodeficiency virus risk, and recidivism among young men leaving jail: evaluation of the REAL MEN re-entry program.

Abstract Purpose This study assesses the impact of REAL MEN (Returning Educated African-American and Latino Men to Enriched Neighborhoods), an intervention designed to reduce drug use, risky sexual behavior and criminal activity among 16–18-year-old males leaving New York City jails. Methods Participants (N = 552) were recruited in city jails and randomly assigned to receive an intensive 30-hour jail/community-based intervention or a single jail-based discharge planning session. All participants were also referred to optional services at a community-based organization (CBO). One year after release from jail, 397 (72%) participants completed a follow-up interview. Logistic and ordinary least squares regression was used to evaluate the impact of the intervention on drug use, risky sexual behavior, criminal justice involvement, and school/work involvement post release. Results Assignment to REAL MEN and, independently, use of CBO services, significantly reduced the odds of substance dependence (odds ratio [OR] = .52, p ≤ .05; OR=.41, p ≤ .05, respectively) 1 year after release. Those assigned to the intervention spent 29 fewer days in jail compared with the comparison group ( p ≤ .05). Compared to non-CBO visitors, those who visited the CBO were more likely to have attended school or found work in the year after release (OR = 2.02, p ≤ .01). Conclusions Jail and community services reduced drug dependence 1 year after release and the number of days spent in jail after the index arrest. While these findings suggest that multifaceted interventions can improve outcomes for young men leaving jail, rates of drug use, risky sexual behavior, and recidivism remained high for all participants after release from jail, suggesting the need for additional policy and programmatic interventions.
Bacterial Enrichments in Surface Films of Freshwater Lakes

Numerous freshwater lakes were examined for enrichment of bacteria in their surface films as compared to their subsurface waters. Surface films were sampled with a glass plate (60-100 μm) surface samples), a Teflon plate (∼7 μm samples), or a hydrophilic Nuclepore filter (∼40 μm samples). Subsurface samples (∼0.1 m) were obtained with a sterile flask. Total bacterial counts were determined by epifluorescent microscopy. Enumerations of benzoic acid-degrading microorganisms were performed using a14C-most-probable-number technique, with 14C-substrate added to lakewater media at μg/L concentrations. Most lakes examined did not show significant enrichments of either total bacteria or benzoic acid-degrading bacteria in their surface films (∼ 10–100 μm samples). Certain highly transparent lakes did show small enrichments of total bacteria in their surface films. A survey of lakes of various transparencies revealed a direct relationship (r = 0.94) between increasing transparency and increasing surface film enrichment of bacteria.
The Experience of Failed Humor: Implications for Interpersonal Affect Regulation

Purpose The purpose of this study was to investigate failed interpersonal affect regulation through the lens of humor. We investigated individual differences that influenced people’s affective and cognitive responses to failed humor and their willingness to persist in the interpersonal regulation of positive affect after a failed attempt.
Microtest plates as a source of error in mixed lymphocyte cultures

Abstract We have determined that microtest plates supplied by 4 manufacturers are not equal in their support of lymphocyte stimulation in mixed lymphocyte cultures. Using lymphocytes isolated from the peripheral blood of normal donors by sedimentation and cotton column purification, we have found that Costar Tissue Culture Cluster plates and Nunclon-Delta Microtest plates consistently allowed the highest lymphocyte stimulation levels and the lowest sample standard errors. Falcon Microtest II plates, on the other hand, were lowest in terms of lymphocyte stimulation, and clearly produced the greatest sample standard error. When normal lymphocytes were isolated for culture using Ficoll-Hypaque gradients, Linbro Tissue Culture Multiwell plates tested superior in terms of lymphocyte stimulation, and equal to the others in sample standard error. It is hypothesized that the selection of an inappropriate microtest plate will introduce unacceptable error in human mixed lymphocyte cultures.
Cyp2c44 epoxygenase in the collecting duct is essential for the high K+ intake-induced antihypertensive effect.

Cytochrome P-450, family 2, subfamily c, polypeptide 44 (Cyp2c44) epoxygenase metabolizes arachidonic acid (AA) to epoxyeicosatrienoic acids (EETs) in kidney and vascular tissues. In the present st...
Patterns of paternal care in primates

An interspecific comparison was carried out to understand better the relationships among paternal care, paternal certainty, and reproductive burden in primates. Although monogamy is generally rare among mammals, a number of primate species are monogamous. Extensive paternal care is a related issue but is one that is not necessarily associated with monogamy or with paternal certainty. For example, despite paternal certainty, primate mothers in monogamous species with body weights over 2 kg still remain the primary infant caretakers, while males in the communally breeding tamarins carry infants more frequently than mothers do, even in the absence of paternal certainty. Several different tactics are used by small-bodied primates to cope with the energetic burden of raising proportionately large infants in an arboreal environment: (1) infant carrying by subadult and/or related nulliparous females (Saimiri, Lemur monogoz); (2) infant carrying by fathers and offspring (Aotus, Callicebus, Saguinus, Cebuella, Leontopithecus); (3) “parking” infants while family members forage (Tarsius, Galago, Microcebus, Cheirogaleus, Varecia); or (4) some combination of the above (Callithrix, Hapalemur, Loris). Lactation length and infant growth patterns appear to influence which of these tactics is employed by a given species. Moreover, although most small-bodied, mated, monogamous female primates spend no more than 9 months annually in gestation and lactation,Aotus andCallicebus mated females are either pregnant or lactating on a year-round basis. It is this heavy female reproductive burden that may be an important factor in selection for extensive paternal care in these monogamous cebids.
Streamer chambers - their use for nuclear science experiments

Abstract A review of the role of streamer chambers in nuclear science work is presented. Included is a brief description of the operating principles of such chambers, some advantages and drawbacks of employing this visual detector for nuclear science experiments, and a discussion of the future usefulness of such devices; both for hadron-nucleus and nucleus-nucleus studies. Several examples of the interactions of both hadron and heavy ion beams with nuclear targets located in a streamer chamber are shown.
Fate of 2,3,7,8-tetrachlorodibenzofuran in the monkey

Abstract The fate of [14C]tetrachlorodibenzofuran (TCDF) was studied in male Rhesus monkeys (Macaca mulatta) after a single iv treatment. Excretion was followed for 21 days post-treatment, and terminal distribution and toxicopathologic studies performed. After 3 weeks, less than 10% of the total dose of 30.7 μg/kg remained in the body. Both the urine and feces served as routes of excretion, with approximately four times more radioactivity being excreted via the fecal than the urinary route. The fat, skin, and liver were the major depots for the [14C]TCDF remaining in the body at 21 days. With the exception of traces of TCDF metabolites in the blood at 21 days, the radioactivity present in the body was parent compound, while radioactivity excreted from the body was in the form of metabolites of [14C]TCDF. Gross morphological alterations were noted in the eyelids of the monkeys at the time of sacrifice. Histopathological changes were detected in the Meibomian glands of the eyelid, the ceruminous glands of the external auditory canal, and in the epithelium of the stomach. Thus, although the disposition of TCDF in monkeys is similar to that previously reported for rats, monkeys clear TCDF from the body more slowly than do rats and are apparently more sensitive to TCDF intoxication.
Moral Mazes: The World of Corporate Managers

The article reviews the book “Moral Mazes: The World of Corporate Managers,” by Robert Jackall.
Simulation of chip form estimation and control for lathe turning

Lathe turning may produce long, continuous chips, or short, broken chips. Broken chips carry away heat and may reduce tool temperature. Continuous chips may snarl and interfere with machine operation. Inside diameter turning or thread cutting may be unusually susceptible to snarls from continuous chips. Other researchers have constructed acoustic emission (AE) chip form monitors. A mathematical model and its advanced continuous simulation language (ACSL) embodiment are described. A simulation study suggests that straight forward modifications hold promise of in-process chip length sensors that can be used for feedback control.
Structure-activity correlations in human kidney aldehyde reductase-catalyzed reduction of para-substituted benzaldehyde by 3-acetyl pyridine adenine dinucleotide phosphate

Abstract Steady-state kinetic parameters of the human kidney aldehyde reductase-catalyzed reduction of para -substituted benzaldehydes by 3-acetyl pyridine dinucleotide phosphate (3-APADPH) were determined. The k cat of aldehyde reduction by 3-APADPH was 2- to 4-fold lower than by NADPH. The dissociation constant of 3-APADPH from the enzyme-coenzyme complex was higher (77 μM) than that of NADPH (5.3 μM). Primary deuterium kinetic isotope effects on both k cat and k cat / K m for para -substituted benzaldehyde reduction by 3-APADPH (with the exception of para -car☐ybenzaldehyde) were equal and on average 2.82 ± 0.21, suggesting that these reactions follow a rapid equilibrium-ordered reaction scheme in which the hydride transfer step is rate-limiting. Multiple regression analysis of the data suggests that benzaldehyde reduction depends upon electronic substituent effects, characterized by a ϱ value of 0.5. These data are consistent with a transition state in which the charge on the aldehyde carbonyl increases relative to the charge on this group in the ground state. A positive deviation of para -car☐ybenzaldehyde from the linear correlation between other benzaldehydes and the substituent constant σ + suggests a specific interaction of the car☐yl substituent of the substrate with the enzyme.
The Cholesterol-Dependent Cytolysin Signature Motif: A Critical Element in the Allosteric Pathway that Couples Membrane Binding to Pore Assembly

The cholesterol-dependent cytolysins (CDCs) constitute a family of pore-forming toxins that contribute to the pathogenesis of a large number of Gram-positive bacterial pathogens.The most highly conserved region in the primary structure of the CDCs is the signature undecapeptide sequence (ECTGLAWEWWR). The CDC pore forming mechanism is highly sensitive to changes in its structure, yet its contribution to the molecular mechanism of the CDCs has remained enigmatic. Using a combination of fluorescence spectroscopic methods we provide evidence that shows the undecapeptide motif of the archetype CDC, perfringolysin O (PFO), is a key structural element in the allosteric coupling of the cholesterol-mediated membrane binding in domain 4 (D4) to distal structural changes in domain 3 (D3) that are required for the formation of the oligomeric pore complex. Loss of the undecapeptide function prevents all measurable D3 structural transitions, the intermolecular interaction of membrane bound monomers and the assembly of the oligomeric pore complex. We further show that this pathway does not exist in intermedilysin (ILY), a CDC that exhibits a divergent undecapeptide and that has evolved to use human CD59 rather than cholesterol as its receptor. These studies show for the first time that the undecapeptide of the cholesterol-binding CDCs forms a critical element of the allosteric pathway that controls the assembly of the pore complex.
Measuring parton densities in the Pomeron.

We present a program to measure the parton densities in the Pomeron using diffractive deep inelastic scattering and diffractive photoproduction, and to test the resulting parton densities by applying them to other processes such as the diffractive production of jets in hadron-hadron collisions. Since QCD factorization has been predicted not to apply to hard diffractive scattering, this program of fitting and using parton densities might be expected to fail. Its success [ital or] [ital failure] will provide useful information on the space-time structure of the Pomeron.
Ultrafast 3D imaging of isolated molecules with electron diffraction

Three-dimensional imaging of molecules in the gas phase has been an important but challenging task, since the randomly oriented molecules only provide one-dimensional structural information. In this work, we show that a three-dimensional structure can be reconstructed from ultrafast electron diffraction from impulsively laser-aligned molecules. The diffraction pattern is taken at the maximum degree of alignment, around two picoseconds after the excitation of the laser. An iterative retrieval algorithm is developed to resolve the problem generated by imperfect alignment and a holographic algorithm is used to reconstruct molecular structure.
Recent Advances in the Study of hsp90 Structure and Mechanism of Action.

Abstract The 90kDa heat shock protein, hsp90, is a major molecular chaperone of the cell that appears to have particular significance to cellular regulatory processes. New tools and approaches have revealed a number of target proteins for hsp90, most of which are protein kinases or transcription factors. While the mechanism of action of hsp90 is not well understood, reasonable models have emerged describing some functional domains of this protein, the importance of conformational transitions for its activity and its role within a multi-component chaperoning pathway of the cell.
Calcium-Magnesium-Aluminosilicate (CMAS) Reactions and Degradation Mechanisms of Advanced Environmental Barrier Coatings

The thermochemical reactions between calcium-magnesium-aluminosilicate- (CMAS-) based road sand and several advanced turbine engine environmental barrier coating (EBC) materials were studied. The phase stability, reaction kinetics and degradation mechanisms of rare earth (RE)-silicates Yb2SiO5, Y2Si2O7, and RE-oxide doped HfO2 and ZrO2 under the CMAS infiltration condition at 1500 C were investigated, and the microstructure and phase characteristics of CMAS-EBC specimens were examined using Scanning Electron Microscopy (SEM) and X-ray Diffraction (XRD). Experimental results showed that the CMAS dissolved RE-silicates to form crystalline, highly non-stoichiometric apatite phases, and in particular attacking the silicate grain boundaries. Cross-section images show that the CMAS reacted with specimens and deeply penetrated into the EBC grain boundaries and formed extensive low-melting eutectic phases, causing grain boundary recession with increasing testing time in the silicate materials. The preliminary results also showed that CMAS reactions also formed low melting grain boundary phases in the higher concentration RE-oxide doped HfO2 systems. The effect of the test temperature on CMAS reactions of the EBC materials will also be discussed. The faster diffusion exhibited by apatite and RE-doped oxide phases and the formation of extensive grain boundary low-melting phases may limit the CMAS resistance of some of the environmental barrier coatings at high temperatures.
Kinetic and Thermodynamic Studies of the Reactivity of (Trimethylsilyl)diazomethane with HMo(CO)3(C5R5) (R = H, Me). Estimation of the Mo−N2CH2SiMe3 Bond Strength and Experimental Determination of the Enthalpy of Formation of (Trimethylsilyl)diazomethane

The rates of reaction of N2CHSiMe3 with HMo(CO)3Cp (Cp = η5-C5H5) in heptane obey the rate law −d[HMo(CO)3Cp]/dt = k[HMo(CO)3Cp][N2CHSiMe3] (k = 0.035 ± 0.01 M−1 s−1 at 0 °C; ΔH⧧ = 11.7 ± 2.0 kcal/mol and ΔS⧧ = −22.0 ± 3.0 cal/(mol K)). Isotopic scrambling between DMo(CO)3Cp and N2CHSiMe3 occurs at a rate faster than the overall reaction. Reversible 1,2-addition to form the tightly bound intermediate [Me3SiCH2Nβ═Nαδ+][δ−Mo(CO)3Cp] is proposed as the first step of the reaction. Spectroscopic and computational data support this formulation. The contact ion pairs can undergo heterolytic cleavage to ions or homolytic cleavage to radicals, and the solvent influence on kobs (THF > toluene > heptane) is interpreted in terms of this model. The enthalpy of this reaction has been measured by solution calorimetry at 272 K in THF: ΔH = −11.6 ± 1.2 kcal/mol. These data, together with computed organic reaction energies allow estimation of the bond strength between the three-electron donors·N2CHSiMe3 and ·Mo(CO)2Cp to b...
The placental transfer of bupivacaine and lidocaine and their myocardial and cerebral uptake in the rabbit.

The uptake of 3H-labelled bupivacaine (0.3 mg/kg) and lidocaine (0.6 mg/kg) by fetal heart and brain tissue and tissue/blood concentration ratios were studied in two groups of fetal rabbits following intravenous bolus injection into the mother. Tritium radioactivity was measured by liquid scintillation technique. Fetal heart/blood as well as brain/blood ratios were constant over time (2 to 45 min after injection). In the lidocaine group, both ratios were significantly higher and about twice the ratios of the bupivacaine group (P < 0.005). There was a significantly higher uptake of 3H-lidocaine than 3H-bupivacaine in the fetal heart and brain. ZUSAMMENFASSUNG Bei zwei Gruppen von Kaninchen wurde die Speicherung von 3H-markiertem Bupivacain (0,3 mg/kg) und Lidocain (0,6 mg/kg) nach Bolus-Injektion bei der Mutter untersucht. Die Tritium-Radioaktivitat wurde mittels der Flussigkeits-Szintilationsmethode gemessen. Der foetale Herz-Blut-Quotient, sowie der Gehirn-Blut-Quotient verhielten sich langere Zeit (2 bis 45 Minuten nach der Injektion) konstant. In der Lidocain-Gruppe waren beide Quotienten signifikant hoher und zwar ca. doppelt so hoch wie in der Bupivacain-Gruppe (P < 0.005). Die 3H-Lidocain-Speicherung im foetalen Herz- und Gehirn-gewebe war signifikant hoher als die von 3H-Bupivacain.
Prediction of indoor radon based on soil radon and soil permeability

Evidence indicates that for homes within a geographically small area, indoor radon can be predicted using soil radon and soil permeability. In northern Virginia, an area of temperate climate and rolling topography, soil measurements taken adjacent to and under 150 homes were compared to their indoor radon. Indoor radon above 5 picoCuries/Liter (pCi/L) occurred in homes with soil radon in excess of 2000 pCi/L, but it also occurred with soil radon as low as 1000 pCi/L if the permeability exceeded 0.5 inches/hour.
The Mycobacterium tuberculosis SecA2 System Subverts Phagosome Maturation To Promote Growth in Macrophages

The ability of Mycobacterium tuberculosis to grow in macrophages is critical to the virulence of this important pathogen. One way M. tuberculosis is thought to maintain a hospitable niche in macrophages is by arresting the normal process of phagosomes maturing into acidified phagolysosomes. The process of phagosome maturation arrest by M. tuberculosis is not fully understood, and there has remained a need to firmly establish a requirement for phagosome maturation arrest for M. tuberculosis growth in macrophages. Other intracellular pathogens that control the phagosomal environment use specialized protein export systems to deliver effectors of phagosome trafficking to the host cell. In M. tuberculosis, the accessory SecA2 system is a specialized protein export system that is required for intracellular growth in macrophages. In studying the importance of the SecA2 system in macrophages, we discovered that SecA2 is required for phagosome maturation arrest. Shortly after infection, phagosomes containing a ΔsecA2 mutant of M. tuberculosis were more acidified and showed greater association with markers of late endosomes than phagosomes containing wild-type M. tuberculosis. We further showed that inhibitors of phagosome acidification rescued the intracellular growth defect of the ΔsecA2 mutant, which demonstrated that the phagosome maturation arrest defect of the ΔsecA2 mutant is responsible for the intracellular growth defect. This study demonstrates the importance of phagosome maturation arrest for M. tuberculosis growth in macrophages, and it suggests there are effectors of phagosome maturation that are exported into the host environment by the accessory SecA2 system.
Hydrolysis of aluminium alkoxides and bayerite conversion

A study of hydrolysis of aluminium alkoxides as a function of water temperature, and structural transformation of the resultant hydroxides was conducted. Hot water hydrolysis of aluminium alkoxides produces boehmite, whereas cold water hydrolysis results in formation of amorphous monohydroxide. This amorphous phase contains OR groups whose removal by water during aging causes the material to convert to bayerite or boehmite. Bayerite conversion takes place below 80 °C by a dissolution-recrystallisation process in which the gradual liberation of OR groups by water appears to play an important role. Boehmite conversion takes place above 80 °C where vigorous liberation of OR groups occurs and the slow stoichiometric bayerite conversion diminishes. Neither conversion takes place in pure alcohol.