cssi/SciSciGPT-SciSciNet huggingface dataset:
Small tokamaks for fusion technology testing

Small steady-state tokamaks for testing divertors and fusion nuclear technologies are considered. Based on present physics and technology data and explanation to reduce R{sub 0}/a, H-D-fueled tokamaks with R{sub 0} {approximately} 0.6--0.75 m, R{sub 0}/a {approximately} 1.8--2.5, and B{sub t0} {approximately} 1.4--2.2 T can be driven with P{sub tot} {approximately} 4.5 MW to maintain I{sub p} {approximately} 0.5 MA and produce the ITER-level plasma edge and divertor conditions. Given an adequate steady-state divertor solution and Q{approximately}1 operation based on fusion through the suprathermal component, D-T-fueled tokamaks with R{sub 0} {approximately} 0.8 m, R{sub 0}/a {approximately} 2, and B{sub t0} {approximately} 4 T can be driven with P{sub tot} {approximately} 15 MW to maintain I{sub p} {approximately} 4.6 MA and produce an peak neutron wall load W{sub L} {approximately} 1 MW/m{sup 2}. Such devices appear possible if the plasma properties at the power R{sub 0}/a remain tokamak-like and, for the D-T case, can unshielded center core is feasible. The use of a single conductor as the inboard leg of the toroidal field coils for this purpose is discussed. The physics issues and the design features are identified for such tokamaks with a testing duty for factor goal of 10--20%.
HF meandered line dipoles optimized with simulated annealing

Electrically small meandered line dipoles for HF (28 MHz) are proposed. The antennas are less than 40% of the length of a conventional half wave dipole, and are self-resonant. The spacing and size of the meandered loops are optimized using simulated annealing; a prototype was constructed to verify the design. Experimental results are consistent with numerical predictions.
Kinetics of precipitation in aluminum alloys during continuous cooling

Rate of cooling from the solution treatment temperature has a pronounced effect on corrosion behavior and mechanical properties of precipitation-hardenable aluminum alloys. This effect is attributed to loss of vacancies and to precipitation of solute during the quench. Analysis of data for aluminum alloys indicates that precipitation rate is an explicit function of temperature and the amount of solute remaining in solution; consequently, precipitation during cooling is additive and can be evaluated by integrating this function. A method is presented whereby type of corrosion attack or mechanical properties can be accurately predicted from the cooling curve and a C-curve for the alloy. Because the actual cooling curve is considered, the method is applicable regardless of the complexity of the cooling conditions. Also presented is an improved method of accurately determining C-curves using either interrupted or continuous quenching techniques. C-curves describing type of corrosion attack in 2024-T4 sheet and loss in mechanical properties of 7075-T6 sheet are presented.
Blocked field effects on collimator scatter factors

In routine dosimetry we assume separability of the collimator and phantom scatter components that together comprise the total scatter factor . In practice, the addition of blocking also affects the photon fluence attributable to the treatment head and flattening filter in a complicated way. The reduced aperture blocks out some of the head scatter contribution, while the block and tray add back secondary scatter. In the following we present techniques for directly measuring the aperture effect on in air or in a full-scatter phantom. The change in is found to be a scaleable quantity that can be modelled as a simple linear fit to the ratio of projected open-to-blocked equivalent square fields. Measurements have been made for 6, 18 and 24 MV photon beams on one Varian 2500 and two Varian 2100c accelerators. Results indicate a progressive loss of collimator scatter contribution with increased field blocking that is amplified with increasing energy. Block and tray scatter only contribute significantly to for large fields and treatment distances of 80 cm or less. Application of these corrections in monitor unit calculations is presented.
Growing Pains: Bioethical Perspectives on Growth Hormone Replacement Research

The debate over growth hormone replacement in older adults reflects a set of contextual issues that are deeper than clinical concerns over the risks and efficacy of the intervention. One question that is central to the public and professional acceptance of growth hormone replacement asks whether the human aging process is an appropriate target for biomedical intervention in the first place. Researchers and clinicians in the field should be prepared to address this question, and this review surveys the major arguments regarding it. Five points of the debate are examined: the relative virtues of human aging, the notion of a "natural" human life cycle, the pathological status of aging, the fairness of anti-aging medicine, and the problem of the "metaphysical misconception" in recruiting human subjects for anti-aging research.
Micro-tomographic imaging of biological specimen by wavelength-scanning digital interference holography

Summary form only given. Three-dimensional tomographic images of microscopic biological specimen are obtained using principle of digital interference holography, from a number of holograms recorded with varying wavelengths. Animated three-dimensional model of object is constructed from the tomographic images.
Conformational change in bacterio-opsin on binding to retinal.

Abstract The detailed mechanism of retinal binding to bacterio-opsin is important to understanding retinal pigment formation as well as to the process of membrane protein folding. We have measured the temperature dependence of bacteriorhodopsin formation from bacterio-opsin and all- trans retinal. An Arrhenius plot of the apparent second-order rate constants gives an activation energy of 11.6±0.7 kcal/mol and an activation entropy of −4±2 cal/mol deg. Comparison of the activation entropy to model compound reactions suggests that chromophore formation in bacteriorhodopsin involves a substantial protein conformational change. Cleavage of the polypeptide chain between residues 71 and 72 has little effect on the activation energy or entropy, indicating that the connecting loop between helices B and C is not involved in this conformational change.
Regional ground-water mixing and the origin of saline fluids: Midcontinent, United States

Ground waters in three adjacent regional flow systems in the midcontinent exhibit extreme chemical and isotopic variations that delineate large-scale fluid flow and mixing processes and two distinct mechanisms for the generation of saline fluids. Systematic spatial variations of major ion concentrations, H, O, and Sr isotopic compositions, and ground-water migration pathways indicate that each flow system contains water of markedly different origin. Mixing of the three separate ground waters exerts a fundamental control on ground-water composition. The three ground waters are: (i) dilute meteoric water recharged in southern Missouri; (ii) saline Na-Ca-Cl water in southeastern Kansas of far-traveled meteoric origin that acquired its salinity by halite dissolution; and (iii) Na-Ca-Cl brines in north-central Oklahoma that may have originated as Paleozoic seawater.
Mindfulness-based stress reduction for overweight/obese women with and without polycystic ovary syndrome: Design and methods of a pilot randomized controlled trial ☆

Abstract Introduction Mindfulness-based stress reduction (MBSR) may be beneficial for overweight/obese women, including women with polycystic ovary syndrome (PCOS), as it has been shown to reduce psychological distress and improve quality of life in other patient populations. Preliminary studies suggest that MBSR may also have salutary effects on blood pressure and blood glucose. This paper describes the design and methods of an ongoing pilot randomized controlled trial evaluating the feasibility and effects of MBSR in PCOS and non-PCOS women who are overweight or obese ( NCT01464398 ). Methods and design Eighty six (86) women with body mass index ≥ 25 kg/m 2 , including 31 women with PCOS, have been randomized to 8 weeks of MBSR or health education control, and followed for 16 weeks. The primary outcome is mindfulness assessed with the Toronto Mindfulness Scale. Secondary outcomes include measures of blood pressure, blood glucose, quality of life, anxiety and depression. Discussion Our overall hypothesis is that MBSR will increase mindfulness and ultimately lead to favorable changes in blood pressure, blood glucose, psychological distress and quality of life in PCOS and non-PCOS women. This would support the integration of MBSR with conventional medical treatments to reduce psychological distress, cardiovascular disease and diabetes in PCOS and non-PCOS women who are overweight or obese.
Normality in k-and-ℵ spaces

Abstract We give examples to show that a k -and-ℵ space need not be normal and that, under MA+¬CH, a k -and-ℵ 0 space need not be monotonically normal. We give several sufficient conditions for the monotone normality of a k -and-ℵ space which involve local properties, coverings by compact sets, and sequential order. Finally, we show that a normal k -and-ℵ space is paracompact.
Explaining the DAMA signal with WIMPless dark matter

Abstract WIMPless dark matter provides a framework in which dark matter particles with a wide range of masses naturally have the correct thermal relic density. We show that WIMPless dark matter with mass around 2–10 GeV can explain the annual modulation observed by the DAMA experiment without violating the constraints of other dark matter searches. This explanation implies distinctive and promising signals for other direct detection experiments, GLAST, and the LHC.
Laparoscopic versus open ventral hernia repairs: 5 year recurrence rates.

Background Current studies with 2-3 year follow-up favor laparoscopic ventral hernia repair due to lower recurrence rates, fewer wound infections, and shorter hospital stays. There is scant data in the literature for this group of patients regarding longer follow-up. This study compares the actual 5 year recurrence rates of laparoscopic versus open techniques and determines factors that may affect recurrence.
Investigation of Burst Pressure in Pipes With Square Wall Thinning by Using FEA and API579 FFS-1

Boilers and pressure vessels are heavily used in chemical industrial plants and equipment is inspected periodically for damage. The most common type of damage is wall thinning due to Flow-Accelerated Corrosion (FAC) or corrosion under insulation (CUI). Any damage must be repaired or replaced as necessary. On the other hand, optimization of the time required in order to replace damaged equipment by evaluating the load carrying capacity of pipes with wall thinning is expected in chemical industrial field. In the present study, FE analysis is used in order to evaluate the load carrying capacity in pipes with wall thinning. Burst pressure is a measure of the load carrying capacity in pipes with wall thinning. The pipes subjected to burst testing are carbon steel tubes for pressure service STPG370 (JIS G3454). The examined wall thinning is rectangular, and the eroded depth is half the pipe wall thickness. The burst pressure is investigated by comparing the results of burst testing with the results of FE analysis. Moreover, the reduced maximum allowable working pressure (MAWPr), which is calculated by fitness-for-service (FFS) assessment, and the safety margin for burst pressure are investigated. The burst pressure calculated by FEA agrees well with the test results, except for square wall thinning for circumferential angles of less than 15°. Also, the safety margin of MAWPr based on FFS-1 Part 4 is over 4.0 times for burst pressure.Copyright © 2013 by ASME
In Vitro HIV Infection Impairs the Capacity of Myeloid Dendritic Cells to Induce Regulatory T Cells

Myeloid dendritic cells (mDCs) are the antigen-presenting cells best capable of promoting peripheral induction of regulatory T cells (Tregs), and are among the first targets of HIV. It is thus important to understand whether HIV alters their capacity to promote Treg conversion. Monocyte-derived DCs (moDCs) from uninfected donors induced a Treg phenotype (CD25+FOXP3+) in autologous conventional T cells. These converted FOXP3+ cells suppressed the proliferation of responder T cells similarly to circulating Tregs. In contrast, the capacity of moDCs to induce CD25 or FOXP3 was severely impaired by their in vitro infection with CCR5-utilizing virus. MoDC exposure to inactivated HIV was sufficient to impair FOXP3 induction. This DC defect was not dependent on IL-10, TGF-β or other soluble factors, but was due to preferential killing of Tregs by HIV-exposed/infected moDCs, through a caspase-dependent pathway. Importantly, similar results were obtained with circulating primary myeloid DCs. Upon infection in vitro, these mDCs also killed Treg through mechanisms at least partially caspase-dependent, leading to a significantly lower proportion of induced Tregs. Taken together, our data suggest that Treg induction may be defective when DCs are exposed to high levels of virus, such as during the acute phase of infection or in AIDS patients.
Mutations in ribonucleic acid binding protein gene cause familial dilated cardiomyopathy.

Objectives We sought to identify a novel gene for dilated cardiomyopathy (DCM). Background DCM is a heritable, genetically heterogeneous disorder that remains idiopathic in the majority of patients. Familial cases provide an opportunity to discover unsuspected molecular bases of DCM, enabling pre-clinical risk detection. Methods Two large families with autosomal-dominant DCM were studied. Genome-wide linkage analysis was used to identify a disease locus, followed by fine mapping and positional candidate gene sequencing. Mutation scanning was then performed in 278 unrelated subjects with idiopathic DCM, prospectively identified at the Mayo Clinic. Results Overlapping loci for DCM were independently mapped to chromosome 10q25-q26. Deoxyribonucleic acid sequencing of affected individuals in each family revealed distinct heterozygous missense mutations in exon 9 of RBM20, encoding ribonucleic acid (RNA) binding motif protein 20. Comprehensive coding sequence analyses identified missense mutations clustered within this same exon in 6 additional DCM families. Mutations segregated with DCM (peak composite logarithm of the odds score >11.49), were absent in 480 control samples, and altered residues within a highly conserved arginine/serine (RS)-rich region. Expression of RBM20 messenger RNA was confirmed in human heart tissue. Conclusions Our findings establish RBM20as a DCM gene and reveal a mutation hotspot in the RS domain. RBM20is preferentially expressed in the heart and encodes motifs prototypical of spliceosome proteins that regulate alternative pre-messenger RNA splicing, thus implicating a functionally distinct gene in human cardiomyopathy. RBM20mutations are associated with young age at diagnosis, end-stage heart failure, and high mortality.
Cancer registry policies in the United States and geographic information systems applications in comprehensive cancer control.

Abstract Objectives Through a long history of cancer policies, public health has a foundation for cancer research and data to use in applying technological advancements for U.S. cancer control efforts. Geographic information systems (GIS) are one technology enabling the visualization of cancer risk patterns associated with incidence, mortality, and accessibility to care. Methods U.S. Comprehensive Cancer Control (CCC) program directors were interviewed from 49 of 50 states to assess use and function of GIS tools for mapping data related to cancer control policies and practices. Interviews were coded to obtain frequencies of response associated with content domains mapped using GIS tools and the perceived relative advantages. Results Significant relationships were found between the mapping of behavioral risk factors, health care services, transportation access, and policy advantages identified by program managers. The mapping of cancer incidence, mortality, and staging, transportation access, and multiple layers of content were found to have significant associations with perceived research advantages. Conclusions U.S. CCC program managers recognize several important advantages relating to health policy and research for use of GIS tools in cancer control efforts. The application of GIS in U.S. cancer control efforts is employed unevenly, suggesting the need for innovative policies to support accessibility.
Evaluation of AIRS, MODIS, and HIRS 11 micron brightness temperature difference changes from 2002 through 2006

In an effort to validate the accuracy and stability of AIRS data at low scene temperatures (200-250 K range), we evaluated brightness temperatures at 11 microns with Aqua MODIS band 31 and HIRS/3 channel 8 for Antarctic granules between September 2002 and May 2006. We found excellent agreement with MODIS (at the 0.2 K level) over the full emperature range in data from early in the Aqua mission. However, in more recent data, starting in April 2005, we found a scene temperature dependence in MODIS-AIRS brightness temperature differences, with a discrepancy of 1- 1.5 K at 200 K. The comparison between AIRS and HIRS/3 (channel 8) on NOAA 16 for the same time period yields excellent agreement. The cause and time dependence of the disagreement with MODIS is under evaluation, but the change was coincident with a change in the MODIS production software from collection 4 to 5.
Kinetics of Reductive Dissolution of Hematite by Bioreduced Anthraquinone-2,6-disulfonate

The reductive dissolution of hematite (alpha-Fe2O3) was investigated in a flow-through system using AH2DS, a reduced form of anthraquinone-2,6-disulfonate (AQDS), which is often used as a model electron shuttling compound in studies of dissimilatory microbial reduction of iron oxides. Influent flow rate, pH, and Fe(II) and phosphate concentrations were varied to investigate the redox kinetics in a flow-through reactor. The hematite reduction rates decreased with increasing pH from 4.5 to 7.6 and decreased with decreasing flow rate. The rates also decreased with increasing influent concentration of Fe(II) or phosphate that formed surface complexes at the experimental pH. Mineral surface properties, Fe(II) complexation reactions, and ADDS sorption on hematite surfaces were independently investigated for interpreting hematite reduction kinetics. AH2DS sorption to hematite was inferred from the parallel measurements of AQDS and AH2DS sorption to alpha-Al2O3, a redox stable analog of alpha-Fe2O3. Decreasing Fe(ll) and increasing AH2DS sorption by controlling flow rate, influent pH, and Fe(II) and phosphate concentrations increased the rates of reductive dissolution. The rates were also affected by the redox reaction free energy when reductive dissolution approached equilibrium. This study demonstrated the importance of the geochemical variables for the reductive dissolution kinetics of iron oxides.
Hydrocode simulation of hypervelocity impact fragmentation

Abstract The Grady-Kipp fragmentation model has been implemented as a constitutive augmentation of the Eulerian hydrocode CTH, and applied in the simulation of oblique hypervelocity impacts on space debris shielding. Comparison of the simulation results to experimentally derived ballistic limit data shows good agreement at an impact velocity of seven killometers per second.
Modeling the interaction of lasers and tissue: importance of accounting for time varying electric properties

Time varying computer models of the interaction of laser light and tissue are very valuable in helping to understand the complexity of the human body and biological tissue. The electrical property of tissue known as permittivity is vital to accurately modeling the interaction of human tissue with lasers. Past laser and RF models have represented the permittivity of the tissue as constant or temperature dependent. This paper presents time dependent permittivity that changes as a result of tissue damage, temperature, blood flow, blood vessels, and tissue property. The models are compared to emphasize the importance of accounting for these different tissue properties. In particular, incorporating the time varying nature of the permittivity of human tissue into the model leads to a significant change seen in tissue damage. An important feature of the model is the feedback loop created between the permittivity, tissue damage, and temperature. The models focus on long time duration applications where the time dependent changes significantly alter the results of the model. The applications for these models lie mostly in the therapeutic area; however, the emphasized points are of consideration for any computer model of the interaction of lasers and tissue.
Transient Poly(ADP-ribosyl)ation of Nuclear Proteins and Role of Poly(ADP-ribose) Polymerase in the Early Stages of Apoptosis

A transient burst of poly(ADP-ribosyl)ation of nuclear proteins occurs early, prior to commitment to death, in human osteosarcoma cells undergoing apoptosis, followed by caspase-3-mediated cleavage of poly(ADP-ribose) polymerase (PARP). The generality of this early burst of poly(ADP-ribosyl)ation has now been investigated with human HL-60 cells, mouse 3T3-L1, and immortalized fibroblasts derived from wild-type mice. The effects of eliminating this early transient modification of nuclear proteins by depletion of PARP protein either by antisense RNA expression or by gene disruption on various morphological and biochemical markers of apoptosis were then examined. Marked caspase-3-like PARP cleavage activity, proteolytic processing of CPP32 to its active form, internucleosomal DNA fragmentation, and nuclear morphological changes associated with apoptosis were induced in control 3T3-L1 cells treated for 24 h with anti-Fas and cycloheximide but not in PARP-depleted 3T3-L1 antisense cells exposed to these inducers. Similar results were obtained with control and PARP-depleted human Jurkat T cells. Whereas immortalized PARP +/+ fibroblasts showed the early burst of poly(ADP-ribosyl)ation and a rapid apoptotic response when exposed to anti-Fas and cycloheximide, PARP −/− fibroblasts exhibited neither the early poly (ADP-ribosyl)ation nor any of the biochemical or morphological changes characteristic of apoptosis when similarly treated. Stable transfection of PARP −/− fibroblasts with wild-type PARP rendered the cells sensitive to Fas-mediated apoptosis. These results suggest that PARP and poly(ADP-ribosyl)ation may trigger key steps in the apoptotic program. Subsequent degradation of PARP by caspase-3-like proteases may prevent depletion of NAD and ATP or release certain nuclear proteins from poly(ADP-ribosyl)ation-induced inhibition, both of which might be required for late stages of apoptosis.
Understanding and reducing persistent poverty in Africa: Introduction to a special issue

Abstract This paper introduces a special issue exploring persistent poverty in sub-Saharan Africa. As a set, these papers break new ground in exploring the dynamics of structural poverty, integrating qualitative and quantitative methods of analysis and adopting an asset-based approach to the study of changes in well-being, especially in response to a wide range of different (climatic, health, political, and other) shocks. In this introductory essay, we frame these studies, building directly on evolving conceptualisations of poverty in Africa.
Spectral fractorization in discrete systems

The spectral factorization in discrete systems is studied in this paper. Three theorems describing the solution and its characteristics are presented. A computer program incorporating this technique is applied to the orbit determination problem using the ranging system.
Phase II collaborative pilot study: preliminary analysis of central neural effects from exposure to volatile anesthetics in the PACU.

Abstract Nurses working in the PACU are occupationally exposed to volatile anesthetics that are exhaled by patients. Few studies have quantified this exposure using breath analysis or have characterized biological effects associated with this exposure. Isoflurane is a widely used anesthetic and is a strong respiratory depressant. Exposure to isoflurane has been shown to cause changes in breathing patterns at low doses. However, biological effects of isoflurane exposure have never been addressed in the occupational setting. This study investigates whether occupational exposure to anesthetic gases has a depressive effect on central neural control of breathing. In this study, concentrations of halogenated anesthetics were quantified in pre- and postshift breath samples of nurses working in the PACU on a Friday and the following Monday. After each breath sample was collected, an occlusion pressure measurement was taken as an indicator of central inspiratory drive. Cumulative nitrous oxide and halogenated anesthetics exposure was measured each day using personal sampling monitors placed close to the nurse's mouth. Exposure to nitrous oxide and isoflurane was significantly higher on Monday than on Friday (P 2 O in preshift samples to 0.85 ± 0.43 cm H 2 O in postshift samples (P =.05). There was no statistical difference in pre- versus postbreath isoflurane or occlusion pressure on Friday. These data indicate that after increased exposure to isoflurane, central neurorespiratory activity was depressed. © 2002 by American Society of PeriAnesthesia Nurses .
Maternal nurturance predicts decreases in attachment avoidance in emerging adulthood

Abstract One of the central tenets of attachment theory is that experiences in early childhood influence people’s approach to social relationships throughout the lifespan. We examined the influence of caregiver nurturance on the development of attachment orientation from adolescence to emerging adulthood in a sample of 103 individuals (50% female). Attachment anxiety decreased from age 14 to 18 and then increased from age 18 to 23; avoidance decreased from age 14 to 23. Higher caregiver nurturance at age 3 was associated with larger declines in avoidance from age 14 to 23. Our findings illustrate how early caregiving experiences continue to shape and influence children’s personality development, nearly twenty years after these experiences occur.
Recent advances in determinant quantum Monte Carlo

AbstractDeterminant quantum Monte Carlo is a method for studying magnetic, transport and thermodynamic properties of interacting fermions on a lattice. It is widely used to explore the physics of strongly correlated quantum systems, from cuprate superconductors to ultracold atoms trapped on optical lattices. This paper contains a description of recent algorithmic advances in the determinant quantum Monte Carlo technique. Focus will be on algorithms developed for hybrid multicore processor and GPU platforms. The resulting speed-up of the simulations will be quantified. Simulations’ results will also be presented, with an emphasis on physical quantities that can now be computed for large numbers of sites.
Oncogene-initiated aberrant signaling engenders the metastatic phenotype: synergistic transcription factor interactions are targets for cancer therapy.

Certain p21GTPases (notably Ras) and some of their guanine nucleotide exchange factors (e.g., Ost, Dbl, Tiam) and downstream mediators (e.g., Raf, Myc) have the potential to promote the development of malignancies because they can enhance the transcription of genes that foster the tumorigenic and metastatic phenotype. Among these are genes that stimulate cell proliferation, confer immortality, and facilitate the invasion of normal tissues. Oncogenes upstream of Ras-cell surface receptors such as ErbB2/Neu, Met, or Trk (and their ligands), and nonreceptor cytoplasmic protein tyrosine kinases such as Src and Abl-not only can act through Ras but also contribute additional signals. This review presents a synopsis of our understanding of signaling pathways controlled by the p21GTPases, with a focus on transcription factors regulated by the pathways. Mutations in one or more of the elements in these signaling pathways are invariably found in cancer cells. Crosstalk among the pathways may explain how some forms of stress can contribute to the development of a malignancy. Abnormal signaling leads to modified cytoskeletal structures and permanently altered (i.e., self-sustaining or epigenetic) transcription of target genes. A common therne is that genes whose transcription is elevated to the greatest extent by Ras often have in their promoters juxtaposed binding sites for two different transcription factors (particularly those in the Fos/Jun, CREB/ATF, NFkB, and Ets families) each of which is activated and such that together they synergize to augment transcription substantially. Some of these transcription factors can also act as oncogenes in certain cell types when appropriately modified and expressed. This unifying theme among many different cancers suggests that strategies to restore the balance among the signaling pathways or to suppress synergistic interactions between transcription factors may prove broadly useful in reversing the malignant phenotype.
Mastitis in early infancy

Aim: To evaluate the clinical features and microbiological findings in young infants with mastitis. Methods: Retrospective review of medical records of 18 infants with breast inflammation during the first 3 mo of life seen in the paediatric emergency department between 1992 and 2002. Results: All were full-term infants with female–male ratio of 3.5∶1. The age ranged from 12 to 45 d, with a peak in the 4th and 5th weeks of life. Only five patients had systemic manifestations, and five were pretreated with oral antibiotics (amoxicillin-clavulanic acid). The latter as well as seven additional cases required incision and drainage due to abscess formation. Bacterial cultures grew Staphylococcus aureus in 10 cases including all pretreated infants. In four of these cases, Gram stain showed the pathogen. After antimicrobial treatment, no recurrence was observed in any of the patients. Conclusions: These findings suggest that mastitis in early infancy should be treated with parenteral antibiotics guided by Gram stain when available and informative. Otherwise, β-lactamase-resistant antibiotics are a reasonable empirical initial treatment pending culture results. Optimizing the management of infants with mastitis is important especially since abscess formation requiring incision may be detrimental for later breast development.
Negotiating notation: Chemical symbols and british society, 1831–1835

Summary One of the central debates among British chemists during the 1830s concerned the use of symbols to represent elements and compounds. Chemists such as Edward Turner, who desired to use symbolic notation mainly for practical reasons, eventually succeeded in fending off metaphysical objections to their approach. These objections were voiced both by the philosopher William Whewell, who wished to subordinate the chemists' practical aims to the rigid standard of algebra, and by John Dalton, whose hidebound opposition to abbreviated notation symbolized the suspicion with which older British chemists perceived continental innovations. It is argued that the success of chemists like Turner in this debate reflects their larger success in the 1830s in achieving disciplinary autonomy and in beginning to align themselves more closely with prevailing chemical practice across the Channel.
Measuring the Oceans From Space

Given the growth in the number and complexity of ocean satellite systems since the launch of Seasat in 1978, combined with the fact that about twenty-five countries are now involved in such observations, this is an appropriate time for a new book on satellite oceanography (Disclosure: the book reviewer has also just published an ocean remote sensing book.). The present book is an expanded version of Robinson's 1985 book, Satellite Oceanography. It consists of two parts: fundamentals of satellite oceanography and remote sensing techniques. Although Robinson originally planned to include a third part on ocean applications, because of the length of the current book, that section will be published separately in 2005. The present book discusses for the ice-free ocean “what is measured and how it is done.”
Identifying prolonged grief reactions in children: dimensional and diagnostic approaches.

Objective Children with prolonged grief reactions (PGR) have been found to be at increased risk for depression and functional impairment. Identifying and diagnosing PGR in children is challenging, as there are no available dimensional measures with established thresholds and no diagnostic criteria in the DSM-IV . We examine thresholds for the Inventory for Complicated Grief–Revised for Children (ICG-RC) and compare this dimensional approach to the proposed DSM-5 criteria for Persistent Complex Bereavement–Related Disorder. We also identify a screening tool for PGR. Method Parentally bereaved children and adolescents, 8 through 17 years of age, were assessed at 9, 21, and 33 months after parental death. Receiver operating characteristics were used to establish the "best threshold" that would identify youth with PGR and evaluate the proposed DSM-5 criteria cross-sectionally and longitudinally. Results A score of 68 or higher on the ICG-RC was found to have high sensitivity (0.942) and specificity (0.965) in differentiating cases of PGR from noncases at 9 months. We also identified a 6-item screening tool that consists of longing and yearning for the deceased, inability to accept the death, shock, disbelief, loneliness, and a changed world view. The proposed DSM-5 criteria correctly identified only 20% to 41.7% of cases with PGR at different time points. Conclusions For the identification of youth at risk for PGR, the dimensional approach outperformed the proposed categorical diagnostic criteria. We propose a brief screening scale that, if validated, can help clinicians to identify bereaved children and adolescents at risk for PGR, and guide the development of prevention and intervention strategies.
The Future of African Archaeology

Ensemble d'articles a propos des questions de base concernant l'information en archeologie africaine, a savoir, ses objectifs, ses moyens de diffusion, son public et ses consequences, ainsi que les elements pragmatiques et logistiques des activites archeologiques
M-mode echocardiograms for determination of optimal left atrial timing in patients with dual chamber pacemakers

Abstract To determine if the A wave of the mitral valve echocardiogram can be used as a marker for left atrial (LA) activity and assist in the programming of dual chamber pacemakers, 156 echocardiograms with the mitral A wave present were obtained from 23 patients with dual chamber pacemakers, all of whom had bipolar esophageal recordings of LA depolarization. Twelve of these patients also underwent hemodynamic study with cardiac function determined at 5 different pacemaker settings: ventricular demand pacing and dual chamber sequential pacing at 0 or 25, 150, 200 and 250 ms programming atrioventricular (AV) delay. The time delay from right atrial pacing artifact to onset and peak of mitral A wave was linearly related to the time from atrial pacing artifact to LA depolarization on the esophageal lead (p
Trace enrichment of biological folates on solid-phase adsorption cartridges and analysis by high-pressure liquid chromatography

Abstract A procedure involving solid-phase adsorption on bonded silica has been developed for trace enrichment and selective recovery of folate monoglutamates from liver tissue. A variety of reverse-phase (ethyl, octyl, octadecyl, phenyl) and anion-exchange (aminopropyl, quarternary amine, primary/secondary amine) cartridges were tested for their potential to adsorb and elute folate monoglutamates from standard solutions (50 nmol each of H4-pteroylglutamic acid (H4PteGlu), 5-CHO-H4PteGlu, 10-CHO-H4PteGlu, PteGlu, and 5-CH3-H4PteGlu). Quantitative recoveries were obtained from aminopropyl (−NH2) and all reverse-phase cartridges. For the analyses of rat liver folates, 20 ml of clear supernatant obtained from 5 g of tissue was treated with conjugase, which released folate monoglutamates from endogenous stores. Folate monoglutamates were then separated from nonfolate material by selective adsorption and recovery from −NH2 extraction cartridges. The procedure also provided a 10-fold concentrate, which allowed direct analysis by HPLC, using C-18 reverse-phase ion-pair columns coupled with uv detection (290 nm). Experiments with standard folates (n = 3) mixed with liver tissue and carried through the extraction, incubation, and trace-enrichment steps showed the following recoveries: 10-CHO-H4PteGlu, 55 ± 5.0%; H4PteGlu, 80 ± 5.0%; 5-CHO-H4PteGlu, 123 ± 12.0%; and 5-CH3-H4PteGlu, 89 ± 3.0%. Endogenous compositions of liver folates (n = 5) were as follows: 10-CHO-H4PteGlu, 1.03 ± 0.3 nmol/g (6.7%); H4PteGlu, 5.70 ± 1.0 (36.4%); 5-CHO-H4Pte Glu, 1.34 ± 0.4 (8.7%); and 5-CH3-H4PteGlu, 7.34 ± 1.2 (48.0%). Chromatographic peaks were identified by their retention times and by comparing their spectral profiles (obtained by a diode array detector) with respective pure folates. We found trace enrichment of biological folates on solid-phase extraction cartridges to be rapid and quantitative. The method allowed, for the first time, direct analysis of tissue folates by HPLC uv methods.
Taxonomic Structure and Productivity of Phytoplankton Assemblages in Crater Lake, Oregon

ABSTRACT Interactions among physical, chemical, and biological components and processes in Crater Lake result in a complex and dynamic ecosystem. In winter and spring, wind energy mixes the lake to a depth of about 200 m. During this period, episodic sinking of cold water below the depth of 200 m produces an upwelling of nutrient-rich water from the deep lake, a process that has a strong influence on the concentrations of nutrients available to phytoplankton in the euphotic zone. Patterns of upwelling are variable from year to year, and physical data indicate that water from the deep lake is completely mixed with surface water every 1–4 years. Phytoplankton cell biovolume and total chlorophyll are distributed uniformly to the depth of 200 m in winter and spring, at which time maximum rates of primary production occur in the upper 60 m of the water column. The onset of thermal stratification in July is associated with development of a chlorophyll maximum at depths between 100 and 140 m and a downward shift...
Conservation of mass and momentum for the flow of interdendritic liquid during solidification

In this paper, mass and momentum conservation equations are derived for the flow of interdendritic liquid during solidification using the volume-averaging approach. In this approach, the mushy zone is conceived to be two interpenetrating phases; each phase is described with the usual field quantities, which are continuous in that phase but discontinuous over the entire space. On the microscopic scale, the usual conservation equations along with the appropriate interfacial boundary conditions describe the state of the system. However, the solution to these equations in the microscopic scale is not practical because of the complex interfacial geometry in the mushy zone. Instead, the scale at which the system is described is altered by averaging the microscopic equations over some representative elementary volume within the mushy zone, resulting in macroscopic equations that can be used to solve practical problems. For a fraction of liquid equal to unity, the equations reduce to the usual conservation equations for a single-phase liquid. It is also found that the resistance offered by the solid to the flow of interdendritic liquid in the mushy zone is best described by two coefficients, namely, the inverse of permeability and a second-order resistance coefficient. For the flow in columnar dendritic structures, the second-order coefficient along with the permeability should be evaluated experimentally. For the flow in equiaxial dendritic structures(i.e., isotropic media), the inverse of permeability alone is sufficient to quantify the resistance offered by the solid.
Amelioration of the physiologic and biochemical changes of acute pancreatitis using an anti-TNF-α polyclonal antibody

Tumor necrosis factor (TNF) is an inflammatory cytokine that may be an important mediator in the development of the systemic sequelae associated with severe acute pancreatitis. The purpose of this study was to determine whether the neutralization of TNF-alpha with a polyclonal antibody could ameliorate selected biochemical parameters of severe pancreatitis in a rat model. Pancreatitis was induced by an antegrade injection of artificial bile into the bile duct. Forty rats were randomized into 4 groups: no surgery (controls), saline infusion to bile duct (sham), placebo treatment in animals with pancreatitis (placebo + Px), and pretreatment with a polyclonal antibody (PAb) in animals with pancreatitis (PAb + Px). Serum TNF-alpha, amylase, calcium, hematocrit, glucose, and ascites volume were measured 2 hours after bile duct infusion. Pretreatment with the PAb produced a significant improvement in all parameters when compared with pancreatitis animals treated with placebo (p < 0.001). In addition, TNF-alpha, which was elevated in animals with pancreatitis, was reduced significantly in treated animals (p < 0.001). These results suggest that TNF-alpha may be an important mediator in the evolution of the systemic manifestations of severe acute pancreatitis.
‘Eddy’ Diffusion in Chromatography (Reply)

VARIANCES add1, for certain independent processes which, by virtue of an elementary random event, contribute directly to the variance. Lateral diffusion is not such a process. The variance is caused by non-equilibrium established by the difference in downstream velocity from point to point. Lateral diffusion acts to reduce this variance as can be seen by the inverse relationship between variance or plate height and diffusion coefficient. The random change in velocity which occurs along a given stream path, as found in packed columns but not in capillary columns, also reduces the variance. Both factors act independently to exchange molecules between fast- and slow-moving regions.
Acculturative stress and psychotic-like experiences among Asian and Latino immigrants to the United States

Previous studies have shown variation in the prevalence and incidence of psychosis across immigrant groups, but the underlying mechanisms are not fully understood. Stress related to acculturation may increase risk for psychosis among immigrant groups. In this study we examine the association between acculturative stress and psychotic-like experiences in a sample of Latino- and Asian-American immigrants to the United States in the National Latino and Asian American Study (n = 2434). Acculturative stress was associated with visual and auditory hallucinations among Asians, but only with hearing voices among Latinos. Increased risk for psychotic-like experiences among Latinos was primarily associated with younger age of immigration. Acculturative stress appears to be a promising candidate mechanism explaining the relationship between immigration and psychosis, particularly among Asian Americans. Ethnic differences may reflect variability between groups that integrate more readily into the host culture and those that are subject to greater discrimination and environmental adversity.
Ccm1 Assures Microvascular Integrity During Angiogenesis

Cerebral cavernous malformations (CCM) are characterized by abnormal dilated intracranial capillaries that predispose to hemorrhage. The development of some CCMs in humans has been attributed to mutations in the CCM1 genes. Currently, contradictory results have been generated regarding the vascular endothelial cell population changes in Ccm1 deficiency in zebrafish. We hypothesize that the inconsistent results simply reflect the spatial and temporal difference for the observed vascular endothelial cells during zebrafish embryonic development. Using high resolution images in vivo, we demonstrated that the loss of Ccm1 in zebrafish embryos leads to marked increases in apoptosis in vascular endothelium at the end stage of microvascular angiogenesis. In vivo zebrafish studies were further substantiated by in vitro findings in human endothelial cells that elucidated the biochemical pathways of CCM1 deficiency. We found that that loss of CCM1 in vitro promotes apoptosis through decreased activation of the integrin-linked kinase survival signaling pathway. In summary, Ccm1 has been identified as a key modulator in maintaining microvascular integrity during zebrafish embryonic angiogenesis.
Hydrodynamics of bivalve shell entrainment and transport

ABSTRACT The relationship between the hydrodynamic properties of disarticulated bivalve shells, and the entrainment and transport of these shells by water currents, was studied by means of flow-visualization experiments and measurements of surface pressure around the shell bodies. The study was performed on eleven bivalve shells, simulated as resting convex-up on the bottom, with their beaks pointing into the flow. The results indicate that bivalve shells respond to hydrodynamic processes in a systematic and predictive manner. Drag and lift were best represented by an exponential relationship between the sum of the projected plan and frontal area of the shells. This relationship supports the argument that greater forces are generated for large, convex and elongated shells. In addition, lift-to drag ratio increased with increasing thickness index (height/length). Roughness elements on shells, such as ribs, produce a drag-reduction transition at high Reynolds numbers, as with spheres, but this transition occurs at lower Reynolds numbers than for spheres. Asymmetry in shells contributes to the development of drag and lift. Large lateral forces were found to be directly related to asymmetry in plan shape. Force-to-shape relationships can be applied to any given shell to determine its transportability and assess the influence of hydrodynamic processes on fossil assemblages. Force resolution was used to calculate entrainment velocities for shells, which were compared with entrainment velocities measured in a recirculating flume. Calculated velocities of 0.2-0.8 m/s were in good agreement with measured velocities. Calculations of entrainment velocity can be used to estimate paleocurrent velocity in the reconstruction of depositional environments.
Specification and Morphogenesis of Astrocytes

Astrocytes are the most abundant cell type in the mammalian brain. Interest in astrocyte function has increased dramatically in recent years because of their newly discovered roles in synapse formation, maturation, efficacy, and plasticity. However, our understanding of astrocyte development has lagged behind that of other brain cell types. We do not know the molecular mechanism by which astrocytes are specified, how they grow to assume their complex morphologies, and how they interact with and sculpt developing neuronal circuits. Recent work has provided a basic understanding of how intrinsic and extrinsic mechanisms govern the production of astrocytes from precursor cells and the generation of astrocyte diversity. Moreover, new studies of astrocyte morphology have revealed that mature astrocytes are extraordinarily complex, interact with many thousands of synapses, and tile with other astrocytes to occupy unique spatial domains in the brain. A major challenge for the field is to understand how astrocytes talk to each other, and to neurons, during development to establish appropriate astrocytic and neuronal network architectures.