cssi/SciSciGPT-SciSciNet huggingface dataset:
Effects of photocycles and periodic ammonium supply on three marine phytoplankton species. II. Ammonium uptake and assimilation.

The relative influence of the photoperiod and of periodic ammonium pulses in entraining the cell division cycle in nitrogen-limited cyclostat cultures differs dramatically in Hymenomonas carterae Braarud and Fagerl, Amphidinium carteri Hulburt and Thalassiosira weissflogii Grun. We examined how each species processes an NH4+ pulse at various times during the cell cycle and the L/D cycle. Rates of NH4+ uptake and changes in cellular concentrations of NH4+, free amino acids, and protein were examined after the addition of an NH4+ pulse. Depletion of NH4+ from the medium occurred earlier when the pulse was given at the beginning of the light period than at the beginning of the dark period in H. carterae and A. carteri. Depletion took longer in the T. weissflogii cultures and the kinetics were similar during both stages of the photocycle in this species. Similarly, the temporal phasing and maximum pool sizes varied with timing of the NH4+ pulse in H. carterae and A. carteri but complete assimilation was relatively rapid. More persistent pools of NH4+ and free amino acids accumulated in T. weissflogii, and the patterns of assimilation varied little as a function of the timing of the pulse with respect to the photocycle. Although nitrogen metabolism occurred rapidly in nitrogen-limited H. carterae and A. carteri, the entrainment of the cell division cycle by the photoperiod resulted in a large degree of uncoupling between completion of nitrogen assimilation and cell division. It is hypothesized that the strong entrainment of the cell division cycle of T. weissflogii by NH4+ pulses results from a relatively slow rate of nitrogen metabolism.
Hindered rotation of the ammonium ion in (NH4)2SnCl6

Abstract The hindered rotational energy levels of the ammonium ion in (NH4)2SnCl6 have been computed. These energy levels are used to interpret the librational frequencies, tunneling frequencies, and rotational heat capacity of the ammonium ion.
Quality-of-life assessment in osteoporosis: health-status and preference-based measures.

Health-status and preference-based approaches to assessing health-related quality of life (HR-QOL) in osteoporosis are reviewed. Osteoporosis-targeted health-status instruments [i.e. Osteoporosis Quality-of-Life Questionnaire (OQLQ), Osteoporosis Assessment Questionnaire (OPAQ), Quality-of-Life Questionnaire of the European Foundation for Osteoporosis (QUALEFFO), Osteoporosis-Targeted Quality-of-Life Questionnaire (OPTQoL), Osteoporosis Functional Disability Questionnaire (OFDQ), Quality-of-Life Questionnaire in Osteoporosis (QUALIOST)], which have been utilised to document the adverse impact of osteoporosis on HR-QOL in diverse clinical and epidemiological studies, are described first. Preference-based approaches to osteoporosis health-outcome measurement are then considered in both clinical and health policy settings. In the clinical setting, direct preference assessments [i.e. visual analogue scale (VAS), time tradeoff (TTO), standard gamble (SG)] using either experienced or described health outcomes have consistently shown significantly lower values for osteoporosis-related health states relative to usual or ideal health. In the health-policy context, preference-classification systems [i.e. EuroQoL (EQ-5D), Health Utilities Index (HUI)] for valuing health in economic studies are reviewed. At present, there is little evidence to guide the choice of one system over another for assessing the cost effectiveness of osteoporosis interventions; however, use of a consistent set of health-state values is essential. Further research is needed to characterise associations between osteoporosis-targeted health-status instruments and preference-based health-outcome measures. In addition, the longitudinal impact of osteoporosis and related fractures on HR-QOL must be documented.
On the Mode of Action of Carbamate Herbicides

The hypothesis of Mann et al. that carbamate herbicides act as anti-derepressor substances was tested in two systems: cell enlargement and proliferation in cultured tobacco pith, and auxin-induced Avena first internode extension. Isopropyl-N-phenylcarbamate (IPC) and isopropyl-N-(3-chIorophenyl carbamate (CIPC) both severely inhibited kinetin-induced cell proliferation in tobacco pith at 10−6M. Auxin-induced tobacco cell enlargement was inhibited to the same degree only at 10−3M. Avena internode extension was insensitive to these compounds in the range 10−3 to 10−7M of IPC and 10−4 to 10−8M CIPC. The results support but do not prove Mann's hypothesis. Results of various studies with carbamates are interpreted in terms of this mechanism.
Luminescence induced by dehydration of kaolin - Association with electron-spin-active centers and with surface activity for dehydration-polymerization of glycine

Experimental data concerning emission of light upon dehydration as a function of preheating and pre-gamma-irradiation are correlated with reported studies of electron-spin resonance (ESR) activity after similar pretreatments. The effect of these pretreatments on the kaolin-promoted incorporation of glycine into peptide oligomers in a wet/cold, hot/dry fluctuating environment is compared to their effect on the ESR and luminescent signals. The existence of spectroscopically active centers appears to be loosely anticorrelated with reaction yield; these yields are increased by increasing the overall energy content of the material. It is concluded that some part of the chemical yield is produced by a mechanism involving intrinsic, excited electronic states of the clay crystal lattice. These states may be derived from thermally, interfacially, and/or mechanically induced charge reorganization within interspersed energy levels in the band structure of the material.
Homoarginine synthesis by rat kidney

Abstract Lysine is transamidinated by enzymes of the kidney to form a compound with the same Chromatographic mobility as homoarginine. The characteristics of the reaction suggest that the enzyme is the same as or similar to l -arginine: glycine amidinotransferase (E.C.2.6.2.1). The identity of the product formed was established as homoarginine by chromatography and nuclear magnetic resonance.
Clinical Experience with Permanent Atrioventricular Sequential Pacing

Abstract In a 23-month period, we implanted 26 permanent atrioventricular (AV) sequential pacing units in 11 women and 15 men ranging from 37 to 85 years old (mean, 68 years). Indications for pacing were complete heart block in 12 patients and sick sinus syndrome in 14 patients. Cardiac index, using standard thermodilution techniques, was determined in 9 patients during ventricular pacing and AV sequential pacing at constant heart rate. Atrioventricular sequential pacing was superior in all patients, with a mean increase in cardiac index of 22% ( p The theoretical hemodynamic advantage of AV sequential pacing has been confirmed in this clinical trial. Experience with electrode placement and improvements in pulse generator design should aid in eliminating complications with this pacing modality.
The realized forward term premium in the repo market

Abstract Repurchase agreements for general-collateral government debt measure the short-term cost of riskless borrowing, thus avoiding issues relating to specialness of Treasury offerings or irregular term-to-maturity in the Treasury bill market. The spread between reverse and repo rates has previously been ignored by researchers who find that the pure expectation hypothesis either holds at this extremely short end of the term structure or that observed deviations from the expectations hypothesis are not economically significant. This paper shows that the time-varying realized forward premium at the short-end of the yield curve is consistently positive when accounting for the spread between repurchase and reverse repurchase agreement rates.
B cells discriminate the rules of engagement.

How B cells discriminate antigen-receptor-mediated signals in development and navigate critical checkpoints in adaptive immune responses remains poorly resolved. In this issue of Immunity, Winslow et al. (2006) conditionally ablate the main regulatory subunit of the calcineurin phosphatase complex in B cells to reveal both positive and negative influences on the development of antibody responses and B cell memory.
Venezuela, Human Rights and Participatory Democracy:

This paper explores the dynamic between the Venezuelan state, which has committed itself to a discourse on grassroots political participation, and civil society, which has responded to this call in...
Interacting with objects compresses environmental representations in spatial memory.

People perceive individual objects as being closer when they have the ability to interact with the objects than when they do not. We asked how interaction with multiple objects impacts representations of the environment. Participants studied multiple-object layouts, by manually exploring or simply observing each object, and then drew a scaled version of the environment (Exp. 1) or reconstructed a copy of the environment and its boundaries (Exp. 2) from memory. The participants who interacted with multiple objects remembered these objects as being closer together and reconstructed smaller environment boundaries than did the participants who looked without touching. These findings provide evidence that action-based perceptual distortions endure in memory over a moving observer’s multiple interactions, compressing not only representations between touched objects, but also untouched environmental boundaries.
Episcopal Applicants to Ordained Ministry: Are They Psychological Healthy?

The current investigation evaluated psychological and personality profiles of applicants to the diaconate and priesthood for several Episcopal dioceses. Applicants included both genders and their ages ranged from 29 to 67 years. A psychological testing battery including the MMPI-2, 16PF, and MCMI-III was administered to 42 applicants between 2008 and 2009 who subsequently entered the diaconate or priestly formation program in the Episcopal Church. Results indicate that these applicants were generally well-adjusted. Findings also suggest some tendency for defensiveness, repression, naivete, and a strong need for affection, as well as for being emotionally stable, intelligent, trusting, and open to change. Finally, results suggest elevations on histrionic, narcissistic, and compulsive measures.
Determination of the Principal Direction of Molecular Orientation in FT-IR Measurement Using Two Polarizers

An optical arrangement using two polarizers is proposed for FT-IR measurement of orientation. Compared with conventional FT-IR using a single polarizer, the new arrangement provides much better discrimination in searching for the principal directions of orientation.
Changes in microtubule polarity orientation during the development of hippocampal neurons in culture.

Microtubules in the dendrites of cultured hippocampal neurons are of nonuniform polarity orientation. About half of the microtubules have their plus ends oriented distal to the cell body, and the other half have their minus ends distal; in contrast, microtubules in the axon are of uniform polarity orientation, all having their plus ends distal (Baas, P.W., J.S. Deitch, M. M. Black, and G. A. Banker. 1988. Proc. Natl. Acad. Sci. USA. 85:8335-8339). Here we describe the developmental changes that give rise to the distinct microtubule patterns of axons and dendrites. Cultured hippocampal neurons initially extend several short processes, any one of which can apparently become the axon (Dotti, C. G., and G. A. Banker. 1987. Nature [Lond.]. 330:477-479). A few days after the axon has begun its rapid growth, the remaining processes differentiate into dendrites (Dotti, C. G., C. A. Sullivan, and G. A. Banker. 1988. J. Neurosci. 8:1454-1468). The polarity orientation of the microtubules in all of the initial processes is uniform, with plus ends distal to the cell body, even through most of these processes will become dendrites. This uniform microtubule polarity orientation is maintained in the axon at all stages of its growth. The polarity orientation of the microtubules in the other processes remains uniform until they begin to grow and acquire the morphological characteristics of dendrites. It is during this period that microtubules with minus ends distal to the cell body first appear in these processes. The proportion of minus end-distal microtubules gradually increases until, by 7 d in culture, about equal numbers of dendritic microtubules are oriented in each direction. Thus, the establishment of regional differences in microtubule polarity orientation occurs after the initial polarization of the neuron and is temporally correlated with the differentiation of the dendrites.
Integrating Neuropsychology and School Psychology: Potential and Pitfalls

The neurological basis of learning disabilities (LD), and other handicapping conditions commonly found in school-age children, makes the integration of neuropsychology and school psychology plausible. However, there has been longstanding debate over the required level of education, training, supervision, and credentialing needed for the practice of neuropsychology in the school and attempts at integration have thus far been controversial. Although the competent practice of school psychology requires some familiarity with neuropsychology foundations, terminology, techniques, and contributions to the understanding of disorders of childhood and adolescence, training guidelines are lacking. The demarcation between psychoeducational and neuropsychological techniques has become increasingly blurred; neuropsychology is already practiced in schools without consensus regarding training and credentialing. This paper briefly traces the history of neuropsychology in the schools from the early 1980s to the present, describing both the potential and the pitfalls for the integration of clinical child neuropsychology and school psychology, including implications for training.
Estimates of radioxenon released from Southern Hemisphere medical isotope production facilities using measured air concentrations and atmospheric transport modeling.

Abstract The International Monitoring System (IMS) of the Comprehensive-Nuclear-Test-Ban-Treaty monitors the atmosphere for radioactive xenon leaking from underground nuclear explosions. Emissions from medical isotope production represent a challenging background signal when determining whether measured radioxenon in the atmosphere is associated with a nuclear explosion prohibited by the treaty. The Australian Nuclear Science and Technology Organisation (ANSTO) operates a reactor and medical isotope production facility in Lucas Heights, Australia. This study uses two years of release data from the ANSTO medical isotope production facility and 133 Xe data from three IMS sampling locations to estimate the annual releases of 133 Xe from medical isotope production facilities in Argentina, South Africa, and Indonesia. Atmospheric dilution factors derived from a global atmospheric transport model were used in an optimization scheme to estimate annual release values by facility. The annual releases of about 6.8 × 10 14 Bq from the ANSTO medical isotope production facility are in good agreement with the sampled concentrations at these three IMS sampling locations. Annual release estimates for the facility in South Africa vary from 2.2 × 10 16 to 2.4 × 10 16 Bq, estimates for the facility in Indonesia vary from 9.2 × 10 13 to 3.7 × 10 14 Bq and estimates for the facility in Argentina range from 4.5 × 10 12 to 9.5 × 10 12 Bq.
Co-design of signal, power, and thermal distribution networks for 3D ICs

Heat removal and power delivery are two major reliability concerns in the 3D stacked IC technology. Liquid cooling based on micro-fluidic channels is proposed as a viable solution to dramatically reduce the operating temperature of 3D ICs. In addition, designers use a highly complex hierarchical power distribution network in conjunction with decoupling capacitors to deliver currents to all parts of the 3D IC while suppressing the power supply noise to an acceptable level. These so called silicon ancillary technologies, however, pose major challenges to routing completion and congestion. These thermal and power/ground interconnects together with those used for signal delivery compete with one another for routing resources including various types of Through-Silicon-Vias (TSVs). This paper presents the work on routing with these interconnects in 3D: signal, power, and thermal networks. We demonstrate how to consider various physical, electrical, and thermo-mechnical requirements of these interconnects to successfully complete routing while addressing various reliability concerns.
The Effects of Growth Hormone on the Utilization of L-Leucine in Adipose Tissue*

Growth hormone (1 μg/ml) increased the oxidation of L-[l-14C]leucine to 14CO2 in adipose tissue of hypophysectomized rats whether or not glucose was also present. Glucose alone also increased the rate of leucine consumption, and the magnitude of the growth hormone effect was greater when glucose was also present. The stimulation of leucine oxidation by growth hormone required a lag period of the order of 30 min, was maximal between 30 and 90 min, and thereafter declined and disappeared by 180 min. Addition of actinomycin D or cycloheximide along with growth hormone caused the accelerated rate of leucine consumption to persist through at least the fourth hour. After the response to growth hormone had disappeared, the tissues were refractory to renewed stimulation with additional growth hormone. Growth hormone produced comparable effects on the consumption of α-ketoisocaproate, the deaminated product of leucine, suggesting that the site of stimulation is distal to the transamination reaction. In the absence...
Reoperation for recurrent carotid stenosis : A ten-year experience

Owing to the supposed risks of reoperation, carotid stenting has been proposed as a treatment for carotid restenosis. The purpose of this study is to determine the safety and efficacy of carotid reoperation. From March 1988 to March 1997, 40 patients, 18 men and 22 women (mean age: 65 years) underwent a total of 43 redo carotid procedures by our group. Two patients had both sides repaired and one required a second reoperation. Symptomatic recurrent carotid stenosis (>70%) was the indication in 25 reoperations and asymptomatic high-grade stenosis (>80%) was the indication in 18. The initial operation in 35 reoperations was carotid endarterectomy (CEA) with primary closure and in eight it was CEA with a prosthetic patch. The interval to recurrence was less in the 24 reoperations in patients who had myointimal hyperplasia (21 months) compared with 17 reoperations in patients with recurrent atherosclerosis (90 months). The other two reoperations were for an intimal flap 2 months after the original CEA, and for operative dilation of fibromuscular dysplastic bands missed on magnetic resonance angiography (MRA), distal to the site of a previous CEA. The technique of reoperation included redo CEA in two, CEA with vein patch in eight, CEA with prosthetic patch in 22, vein interposition graft in five, and prosthetic interposition graft in five. In addition, operative dilation with an arterial dilator was used in one reoperation. No perioperative strokes or deaths occurred other than one patient who died from cardiac complications following combined CEA and coronary artery bypass grafting. Operative morbidity consisted of pneumonia in one patient, reversible cranial nerve injury in four, and hematoma requiring evacuation in two. During follow-up (mean: 34 months), carotid occlusion resulted in a mild stroke in one patient, there were 10 late deaths not related to carotid disease, one patient required a reoperation, and three patients were lost to follow-up. The authors conclude that reoperation for recurrent carotid stenosis, using standard vascular techniques, is both safe and effective; it should continue to be the mainstay of treatment when intervention is required.
Quantifying U.S. aluminum in-use stocks and their relationship with economic output

Abstract A dynamic material flow analysis model is developed to quantify aluminum in-use stocks and old scrap recycling and recovery in the United States for the period of 1900 to 2007. The total in-use aluminum stock in 2007 is estimated as 93 million metric tons, which represents approximately 34% of the cumulative apparent consumption since 1900. Alternately, since 1900 nearly 40% of the cumulative discarded aluminum has not been recycled for domestic use in the U.S. or for export to foreign consumers. Statistical time series analysis is used to explore the relationship between model results of in-use stocks and gross domestic product (GDP). Unlike most previous studies of material consumption and economic activity, which ignore the statistical properties of time series data to the detriment of model estimation and inference, data stationarity is explicitly evaluated through unit root testing and model specification is adjusted accordingly. The annual percentage change in GDP is found to have a large and significant association with the annual percentage change in net additions to in-use stocks. Model sensitivity and uncertainty are quantified through the application of the Fourier Amplitude Sensitivity Test and alternate specifications of product lifetime probability density functions.
Does interview mode matter for food security measurement? Telephone versus in-person interviews in the Current Population Survey Food Security Supplement

Objective: To assess whether interview mode (telephone vs. in-person) affects the results of surveys that measure food security. Design: Responses given by households interviewed by telephone and in-person in recent US Current Population Survey Food Security Supplements (CPS-FSS) were compared. Statistical methods based on the Rasch measurement model were used to assess whether response patterns differed between the two interview modes. Multivariate logistic regression analysis was then used to gauge the effect of interview mode on the measured household prevalence rates of food insecurity and very low food security while controlling for income, employment, household structure, and other household characteristics that affect food security. Results: Response patterns to the indicators that comprise the food security scale did not differ substantially between interview modes. Prevalence rates of food insecurity and very low food security estimated from the two interview modes differed by only small proportions after accounting for differences in the socioeconomic characteristics of households. Conclusions: Findings suggest that effects of interview mode on food security measurement in the CPS-FSS are small, or at most modest. Prevalence estimates may be biased upwards somewhat for households interviewed in-person compared with those interviewed by telephone. The extent to which these results can be generalised may depend, to some extent, on survey characteristics other than interview mode, such as surveyor name recognition and respondents’ trust and confidence in the surveyor.
Nutrition in the Elderly

Publisher Summary This chapter discusses dietary limitations associated with prevalent chronic diseases; medications affecting appetite and nutrient use in the body; and highlights topics related to diversity and aging. Adequate nutrition plays a vital role in health maintenance and disease prevention at every age and can highly benefit the lives of older adults. Nutrition status is fundamental to the quality of life in the aging person as it is closely associated with functionality and the ability to remain independent. Maintenance of a healthy body weight in the face of aging, with the prevention of both underweight and obesity, can reduce the symptoms of chronic health conditions and have a protective effect against mortality. However, physiological and social changes that naturally occur with aging may lead to reduced appetite and food intake, body weight changes, malnutrition, and a compromised immune system. Early identification of nutrition deficiencies and timely intervention can improve length and quality of life. In order to identify any nutritional risks in the elderly, nutrition assessment is crucial. The Modified MyPyramid for Older Adults is a useful guide to assess the well older person's diet and highlights age specific nutrition needs. Additionally, there are four commonly used tools to evaluate the nutrition status in the elderly that includes anthropometric, biomedical, clinical, dietary and economic data (ABCDEs), the Mini Nutritional Assessment, Council on Nutrition Appetite Questionnaire (CNAQ) and Simplified CNAQ (SNAQ), and Geriatric Nutritional Risk Index (GNRI).
Risk of Heart Failure Among Postmenopausal Women: A Secondary Analysis of the Randomized Trial of Vitamin D Plus Calcium of the Women's Health Initiative

Background—Vitamin D supplementation may be an inexpensive intervention to reduce heart failure (HF) incidence. However, there are insufficient data to support this hypothesis. This study evaluates whether vitamin D plus calcium (CaD) supplementation is associated with lower rates of HF in postmenopausal women and whether the effects differ between those at high versus low risk for HF. Methods and Results—Analyses were restricted to 35 983 (of original 36 282) women aged 50 to 79 years old in the Women’s Health Initiative randomized trial of CaD supplementation who were randomized 1:1 in a double-blinded fashion to receive 1000 mg/d of calcium plus 400 IU/d of vitamin D3 or placebo. Overall, 744 adjudicated incident HF cases (intervention, 363; control, 381) occurred during a median follow-up of 7.1 (interquartile range, 1.6) years. CaD supplementation, compared with placebo, was not associated with reduced HF risk in the overall population, hazard ratio, 0.95; P=0.46. However, CaD supplementation had dif...
Testosterone propionate therapy in one hundred cases of angina pectoris.

IN PREVIOUS communications (3, 4), the beneficial effects of testosterone propionate therapy in 46 patients with angina pectoris have been reported. The present report is based on a series of 100 consecutive patients with angina pectoris who have received thisform of therapy. They have been followed over periods varying from several months to as long as five years. Care was exercised in the choice of patients. No patient was treated unless the diagnosisof angina pectoris was clearly established. This diagnosis was based on a history of typical attacks of substernal or precordial pain precipitated by exertion or emotion and relieved by rest or nitroglycerin. In many of these patients, the pain radiated to one or both arms, shoulders, back or jaw. METHOD AND RESULTS One hundred patients with angina pectoris, 92 men and 8 women, ranging from 34 to 77 years in age, received testosterone propionate therapy.1 Ninety-one showed moderate to marked improvement, while 9 had no noticeable beneficial effects.
The U.S. pediatric cancer clinical trials programmes: international implications and the way forward.

Abstract The four national paediatric cancer clinical trials organisations in the United States—the Children's Cancer Group, the National Wilms' Tumor Study Group, the Intergroup Rhabdomyosarcoma Study Group and the Pediatric Oncology Group—were formed in 1955, 1969, 1972 and 1979, respectively. Together, the Children's Cancer Group and Pediatric Oncology Group serve as a national registry of nearly all childhood cancers in the United States, provide a national network of communication for researchers, care providers and families of paediatric patients with malignant disease and conduct laboratory investigations and clinical trials of new treatments of cancers in infants, children, adolescents and young adults. Nearly 95% of patients with cancer in the United States who are below 15 years of age are registered by the Children's Cancer Group and the Pediatric Oncology Group and more than half of American children with cancer are entered into at least one trial by a paediatric group. Improved survival of children receiving treatment according to well-defined protocols in specialised children's centres, in contrast to children who received treatment outside of these centres, has been shown for those with acute lymphoblastic leukaemia, lymphoma, Wilms' tumour, medulloblastoma, rhabdomyosarcoma and Ewing's sarcoma. By the year 2000, the overall cure rate for United States children and adolescents with cancer should exceed 85%. To reach this goal, the way forward will depend on international collaboration, implementation of global harmonisation, prevention of the erosion of biomedical research and clinical trials by the managed health care industry, increased public and private financial support and continued recruitment into paediatric oncology of brilliant and dedicated young investigators. The specific challenges ahead include: (1) transferring the knowledge, methodologies and technologies to countries that are less fortunate; (2) conducting multinational clinical trials in conjunction with paediatric cooperative groups in other countries; (3) accessing older adolescent patients who currently do not participate in cooperative group trials; (4) merging clinical trials by adult collaborative groups that overlap with the paediatric groups, as in acute lymphoblastic leukaemia, acute myelogenous leukaemia, Hodgkin's disease, osteosarcoma and germ cell tumours; (5) establishing a stable source of funding for national and international cooperative paediatric cancer clinical trials; (6) creating an informatics system that can link paediatric cooperative group operation centres around the world, and the institutions within each collaborative group; and (7) securing the support of the insurance industry and government in covering clinical trials.
Combined Effects of Shear Thinning and Viscous Heating on EHL Characteristics of Rolling/Sliding Line Contacts

The combined influence of shear thinning and viscous heating on the behavior of film thickness and friction in elastohydrodynamic lubrication (EHL) rolling/sliding line contacts is investigated numerically. The constitutive equation put forward by Carreau is incorporated into the model to describe shear thinning. An extensive set of numerical simulations is presented. Comparison of the film thickness predictions with published experiments reveals good agreement, and it is shown that thermal effect plays an important role in the precise estimation of EHL film thickness and friction coefficient. Parametric simulations show that thermal effect in shear-thinning fluids is strongly affected by the power-law index used in the Carreau equation. Comparisons of prediction of the Newtonian fluid model are presented to quantify the degree to which it overestimates the film thickness.
Detection improvement in spatially filtered x-ray fluoroscopy image sequences.

The effect of spatial noise-reduction filtering on human observer detection of stationary cylinders mimicking arteries, catheters, and guide wires in x-ray fluoroscopy was investigated in both single image frames and image sequences. Ideal edge-preserving spatial filtering was simulated by filtering of the noise before addition of the target cylinder. This allowed us to separate the effect of edge blurring from those of noise reduction and spatial noise correlation. We used three different center-weighted averagers that reduced pixel noise variance by factors of 0.75, 0.50, and 0.25. As compared with no filtering, the effect of filtering on detection in single images was statistically insignificant. This indicated an adverse effect of spatial noise correlation on detection that countered the effect of noise reduction. By comparison, spatial filtering significantly improved detection in image sequences and yielded potential x-ray dose savings of 26–34%. Comparison of results with two observer models suggested that human observers have an improved detection efficiency in spatially filtered image sequences as compared with white-noise sequences. Pixel noise reduction, a measure commonly used to assess filter performance, overestimated the effect of filtering on detection and was not a good indicator of image quality. We conclude that edge-preserving spatial filtering is more effective in sequences than in single images and that such filtering can be used to improve image quality in noisy image sequences such as x-ray fluoroscopy.
Solutions for Severely Angulated Implants in the Mandibular Overdenture: A Clinical Report

Results of randomized clinical trials have confirmed that implant overdentures provide patients with better outcomes than do conventional complete dentures. Several designs have been introduced for the mandibular implant-retained removable prosthesis. The most commonly used prosthesis design for the mandibular overdenture is two implants in the canine areas with a stud attachment mechanism (i.e., ball attachments). This design is the least expensive, and therefore can service more patients and is now considered to be the "Standard of Care" for the mandibular edentulous patient. Proper treatment planning and execution lead to favorable implant placement and a successful prosthetic restoration and ultimately patient satisfaction; however, implant malposition may occur, which can lead to an unsuccessful prosthesis. This clinical report describes an implant overdenture design used for severely angled implants. Prosthodontic techniques that enabled this patient to have a successful outcome included the use of cast-to attachments and abutments along with a sectional matrix used to locate these components within the bulk of the prosthesis. For this patient the prosthodontic compromises were preferred over another surgical procedure with the additional time, discomfort, increased cost, and possible surgical morbidity. It is important that the patient understand the compromises and potential problems when implant placement is not ideal, especially the potential for implant overload and failure.
Tunneling and the spectrum of the Potts model.

The three-dimensional, three-state Potts model is studied as a paradigm for high-temperature quantum chromodynamics. In a high-statistics numerical simulation using a Swendson-Wang algorithm, we study cubic lattices of dimension as large as 64[sup 3] and measure correlation functions on long lattices of dimension 20[sup 2][times]120 and 30[sup 2][times]120. These correlations are controlled by the spectrum of the transfer matrix. This spectrum is studied in the vicinty of the phase transition. The analysis classifies the spectral levels according to an underlying [ital S][sub 3] symmetry. Near the phase transition the spectrum agrees nicely with a simple four-component Hamiltonian model. In the context of this model, we find that low-temperature ordered-ordered interfaces nearly always involve a disordered phase intermediate. We use a spectral method for determining the surface tension between phases.
A High-Resolution Imaging Approach to Investigate Chromatin Architecture in Complex Tissues

We present ChromATin, a quantitative high-resolution imaging approach for investigating chromatin organization in complex tissues. This method combines analysis of epigenetic modifications by immunostaining, localization of specific DNA sequences by FISH, and high-resolution segregation of nuclear compartments using array tomography (AT) imaging. We then apply this approach to examine how the genome is organized in the mammalian brain using female Rett syndrome mice, which are a mosaic of normal and Mecp2-null cells. Side-by-side comparisons within the same field reveal distinct heterochromatin territories in wild-type neurons that are altered in Mecp2-null nuclei. Mutant neurons exhibit increased chromatin compaction and a striking redistribution of the H4K20me3 histone modification into pericentromeric heterochromatin, a territory occupied normally by MeCP2. These events are not observed in every neuronal cell type, highlighting ChromATin as a powerful in situ method for examining cell-type-specific differences in chromatin architecture in complex tissues.
Spatial and temporal accuracy of a flexible multi-camera motion-tracking system for motion correction of cardiac SPECT

552 Objectives: In cardiac SPECT imaging, motion has been reported to occur about 25% of the time and in 5% of these cases it is significant enough to cause artifacts which can mislead diagnosis. In our clinic, we have implemented a motion-tracking system utilizing infrared cameras to track retro-reflective markers on stretchy bands wrapped about patients. Our aim was to have a robust system that would enable motion-tracking even when multiple camera views were blocked via patient anatomy or viewing geometry. Methods: 5 infrared cameras with control box and stereo software were purchased from Vicon and integrated with our SPECT system via LabVIEW. 3 cameras view patients from the front side of the SPECT system, and 2 cameras view from the back. The cameras are wall-mounted to be unobtrusive, and are aligned to view the SPECT imaging volume. Any 2 of these cameras can form stereo pairs for the estimation of marker location, with one stereo pair the minimum requirement. Thus, the system flexibly adapts to the number of visible markers as the SPECT detectors rotate. Motion tracking was synchronized with acquisition on our SPECT system using LabVIEW-generated signals. Stereo calibration takes 2-3 minutes and then the Vicon coordinate system is automatically converted to the SPECT coordinate system by recording the location of additional markers rigidly attached to the SPECT gantry. Results: We determined that our tracking system has sub-millimeter positional accuracy as well as 0.1mm positional repeatability. In testing synchronization between the tracking system and list-mode emission acquisition, it was determined that temporal localization of motion by the Vicon and SPECT systems agreed to within 100 msec. Using volunteers with 4 marker bands wrapped around their chest and abdomen during simulated SPECT imaging, we were able to consistently track at least 7 of the 8 markers. Conclusions: We have determined that this system provides sufficient spatial and temporal accuracy to enable motion tracking of patients during SPECT imaging. We therefore are instituting a clinical trial of the system.
The Effects of Soil Moisture and Emergent Herbaceous Vegetation on Carbon Emissions from Constructed Wetlands

Wetlands serve as sinks for carbon and nutrients but they are also a large source of greenhouse gases. Our objective was to quantify emissions of carbon dioxide (CO2) and methane (CH4) from three free water surface-flow constructed wetlands in the presence and absence of emergent herbaceous vegetation (Typha angustifolia L. and Typha latifolia L.) across a gradient of soil moisture. Measurements were collected on eight sampling dates during June and July, 2014. Similar to previous research, CO2 emissions were higher in vegetated plots, increasing from a median ± std. error of 242 ± 29 to 1612 ± 95 mg m−2 h−1. Emissions of CH4 were also significantly higher in vegetated plots, but the relative magnitude of the effect of plants varied among wetlands. Emissions of CH4 were highest from vegetated plots in the wetland with the highest soil moisture (4.4 ± 1.0 mg m−2 h−1). However, the largest effect of plants on methane emissions occurred in the wetland with intermediate soil moisture, with a 15-fold increase in CH4 emissions from 0.15 ± 0.90 to 2.4 ± 1.2 mg m−2 h−1. Design and management that consider the interactive effects of soil moisture and plants on CH4 emissions may help reduce the greenhouse gas footprint of constructed wetlands.
Creating More Effective Mentors: Mentoring the Mentor

Given the diversity of those affected by HIV, increasing diversity in the HIV biomedical research workforce is imperative. A growing body of empirical and experimental evidence supports the importance of strong mentorship in the development and success of trainees and early career investigators in academic research settings, especially for mentees of diversity. Often missing from this discussion is the need for robust mentoring training programs to ensure that mentors are trained in best practices on the tools and techniques of mentoring. Recent experimental evidence shows improvement in mentor and mentee perceptions of mentor competency after structured and formalized training on best practices in mentoring. We developed a 2-day "Mentoring the Mentors" workshop at UCSF to train mid-level and senior HIV researchers from around the country [recruited mainly from Centers for AIDS Research (CFARs)] on best practices, tools and techniques of effective mentoring. The workshop content was designed using principles of Social Cognitive Career Theory (SCCT) and included training specifically geared towards working with early career investigators from underrepresented groups, including sessions on unconscious bias, microaggressions, and diversity supplements. The workshop has been held three times (September 2012, October 2013 and May 2015) with plans for annual training. Mentoring competency was measured using a validated tool before and after each workshop. Mentoring competency skills in six domains of mentoring-specifically effective communication, aligning expectations, assessing understanding, fostering independence, addressing diversity and promoting development-all improved as assessed by a validated measurement tool for participants pre- and -post the "Mentoring the Mentors" training workshops. Qualitative assessments indicated a greater awareness of the micro-insults and unconscious bias experienced by mentees of diversity and a commitment to improve awareness and mitigate these effects via the mentor-mentee relationship. Our "Mentoring the Mentors" workshop for HIV researchers/mentors offers a formal and structured curriculum on best practices, tools and techniques of effective mentoring, and methods to mitigate unconscious bias in the mentoring relationship. We found quantitative and qualitative improvements in mentoring skills as assessed by self-report by participants after each workshop and plan additional programs with longitudinal longer-term assessments focused on objective mentee outcomes (grants, papers, academic retention). Mentoring training can improve mentoring skills and is likely to improve outcomes for optimally-mentored mentees.
Gas-phase CO2 subtraction for improved measurements of the organic aerosol mass concentration and oxidation degree by an aerosol mass spectrometer.

The Aerodyne aerosol mass spectrometer (AMS) has been widely used for real-time characterization of the size-resolved chemical composition of sub-micrometer aerosol particles. The first step in AMS sampling is the pre-concentration of aerosols while stripping away the gas-phase components, which contributes to the high sensitivity of this instrument. The strength of the instrument lies in particle phase measurement; however, ion signals generated from gas-phase species can influence the interpretation of the particle-phase chemistry data. Here, we present methods for subtracting the varying contributions of gas-phase carbon dioxide (CO2) in the AMS spectra of aerosol particles, which is critical for determining the mass concentration and oxygen-to-carbon (O/C) ratio of organic aerosol. This report gives details on the gaseous CO2 subtraction analysis performed on a high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) data set acquired from sampling of fresh and diluted vehicle emissions. ...
Comparison of Two Commercial Treatment Planning Systems Variseed and Mim for Low-Dose-Rate Prostate Brachytherapy

operative transrectal ultrasound volume (CT/TRUS ratio) was significantly less for thin seed patients than for standard seed patients (p50.0015). For the standard seed group, the volumetric difference between the preoperative TRUS and post-operative CT tended to be greater in smaller sized prostates. However, in the thin seed patients, the volume variation between the preoperative TRUS and postoperative CT was independent of prostate size. Of the factors considered a priori to be potential predictors of prostate swelling (initial prostate volume, number of needles, prior hormonal therapy, group, operative time), only group was shown to significantly impact on prostate swelling on multivariate analysis, with less swelling in thin seed patients. Conclusions: I thin seeds (ThinSeed, Oncura Pty Ltd) are associated with an initial learning curve in terms of operative time, even among experienced brachytherapists. Their ability to reduce prostate swelling, and the implications in terms of reducing timing-dependent variations in post-implant dosimetry, as well as acute urinary morbidity, deserves further exploration.
Room Temperature Atomic Layer-like Deposition of ZnO on Functionalized Self-Assembled Monolayers

The room temperature atomic layer-like deposition (ALLD) of ZnO using diethylzinc (DEZ) and water precursors has been investigated on −COOH, −OH, and −CH3 terminated self-assembled monolayers. The detailed reaction pathways of ZnO ALLD on −COOH and −OH terminated SAMs are different. As expected on −OH terminated SAMs, the DEZ reacts with the hydroxyl group. However, on −COOH terminated SAMs DEZ reacts with both the carbonyl and hydroxyl bonds present and can lead to the formation of a ketone rather than ZnO deposition. The growth rates on these SAMs are different; after the first ALLD cycle the measured growth rates are 3.0 ± 0.1 and 3.4 ± 0.2 A/cycle on −COOH and −OH terminated SAMs, respectively. XPS analyses show that the initial composition of the deposited layer on −COOH terminated SAMs is similar to Zn(OH)2. After five ALLD cycles the −COOH terminated SAM is completely covered, and XPS analyses indicate that the deposited film is composed of ZnO. In contrast on −OH terminated SAMs, the deposited fil...
Dangling bonds and vacancies in germanium

The quest for metal-oxide-semiconductor field-effect transistors (MOSFETs) with higher carrier mobility has triggered great interest in germanium-based MOSFETs. Still, the performance of germanium-based devices lags significantly behind that of their silicon counterparts, possibly due to the presence of defects such as dangling bonds (DBs) and vacancies. Using screened hybrid functional calculations we investigate the role of DBs and vacancies in germanium. We find that the DB defect in germanium has no levels in the band gap; it acts as a negatively charged acceptor with the (0/$\ensuremath{-}$1) transition level below the valence-band maximum (VBM). This explains the absence of electron-spin-resonance observations of DBs in germanium. The vacancy in germanium has a much lower formation energy than the vacancy in silicon and is stable in a number of charge states, depending on the position of the Fermi level. We find the (0/$\ensuremath{-}$1) and ($\ensuremath{-}$1/$\ensuremath{-}$2) transition levels at 0.16 and 0.38 eV above the VBM; the spacing of these levels is explained based on the strength of intraorbital repulsion. We compare these results with calculations for silicon, as well as with available experimental data.