Light inhibition of nitrification in sea-surface films

Nitrifying bacteria (ammonia- and nitrite-oxidizers) were isolated from sea-surface films collected in the Gulf of California. Laboratory studies indicate substrate oxidation by these isolates is inhibited by light. Ammonia-oxidizers showed lower nitrifying activity and a longer lag time when held in an 8-hr light:16-hr dark regime compared to those held completely in the dark, and nitrite-oxidizers showed nitrifying activity only when held in the dark. Tracer studies using 15N-ammonia corroborate that little or no nitrification occurs in the surface films of subtropical seas

A Radiation Oncology Based Electronic Health Record in an Integrated Radiation Oncology Network

Purpose: The goal of this ongoing project is to develop and integrate a comprehensive electronic health record (EHR) throughout a multi-facility radiation oncology network to facilitate more efficient workflow and improve overall patient care and safety. Methodology: We required that the EHR provide pre-defined record and verify capability for radiation treatment while still providing a robust clinical health record. In 1996, we began to integrate the Local Area Network Treatment Information System (LANTIS®) across the West Penn Allegheny Radiation Oncology Network (currently including 9 sites). By 2001, we began modifying and expanding the assessment components and creating user-defined templates and have developed a comprehensive electronic health record across our network. Results: In addition to access to the technical record and verify information and imaging obtained for image-guided therapy, we designed and customized 6 modules according to our networks needs to facilitate information acquisition, tracking, and analysis as follows: 1) Demographics/scheduling; 2) Charge codes; 3) Transcription/clinical documents; 4) Clinical/technical assessments; 5) Physician orders 6) Quality assurance pathways. Each module was developed to acquire specific technical/clinical data prospectively in an efficient manner by various staff within the department in a format that facilitates data queries for outcomes/statistical analyses and promotes standardized quality guidelines resulting in a more efficient workflow and improved patient safety and care. Conclusions: Development of a comprehensive EHR across a radiation oncology network is feasible and can be customized to promote clinical/technical standards, facilitate outcomes studies, and improve communication and peer review. The EHR has improved patient care and network integration across a multi-facility radiation oncology system and has markedly reduced the flow and storage of paper across the network

Global oceanic production of nitrous oxide

We use transient time distributions calculated from tracer data together with in situ measurements of nitrous oxide (N2O) to estimate the concentration of biologically produced N2O and N2O production rates in the ocean on a global scale. Our approach to estimate the N2O production rates integrates the effects of potentially varying production and decomposition mechanisms along the transport path of a water mass.We estimate that the oceanic N2O production is dominated by nitrification with a contribution of only approximately 7 per cent by denitrification. This indicates that previously used approaches have overestimated the contribution by denitrification. Shelf areas may account for only a negligible fraction of the global production; however, estuarine sources and coastal upwelling of N2O are not taken into account in our study. The largest amount of subsurface N2O is produced in the upper 500 m of the water column. The estimated global annual subsurface N2O production ranges from 3.1+/-0.9 to 3.4+/-0.9 Tg N yr^-1. This is in agreement with estimates of the global N2O emissions to the atmosphere and indicates that a N2O source in the mixed layer is unlikely. The potential future development of the oceanic N2O source in view of the ongoing changes of the ocean environment (deoxygenation, warming, eutrophication and acidification) is discussed

On the simple random-walk models of ion-channel gate dynamics reflecting long-term memory

Several approaches to ion-channel gating modelling have been proposed. Although many models describe the dwell-time distributions correctly, they are incapable of predicting and explaining the long-term correlations between the lengths of adjacent openings and closings of a channel. In this paper we propose two simple random-walk models of the gating dynamics of voltage and Ca2+-activated potassium channels which qualitatively reproduce the dwell-time distributions, and describe the experimentally observed long-term memory quite well. Biological interpretation of both models is presented. In particular, the origin of the correlations is associated with fluctuations of channel mass density. The long-term memory effect, as measured by Hurst R/S analysis of experimental single-channel patch-clamp recordings, is close to the behaviour predicted by our models. The flexibility of the models enables their use as templates for other types of ion channel

Ammonium regeneration: Its contribution to phytoplankton nitrogen requirements in a eutrophic environment

Ammonium regeneration, nutrient uptake, bacterial activity and primary production were measured from March to August 1980 in Bedford Basin, Nova Scotia, Canada, a eutrophic environment. Rates of regeneration and nutrient uptake were determined using 15N isotope dilution and tracer methodology. Although primary production, nutrient uptake and ammonium regeneration were significantly intercorrelated, no relationship was detected between these parameters and heterotrophic activity. The average contribution of ammonium to total nitrogen (ammonium+nitrate) uptake was similar in the spring and in the summer (approximately 60%). On a seasonal average basis, 36% of the phytoplankton ammonium uptake could be supplied by rapid remineralization processes. In spite of the high average contribution of NH4 regeneration to phytoplankton ammonia uptake, there is indirect evidence suggesting that other NH4 sources may occasionally be important

Voltage-Dependent Gating in a “Voltage Sensor-Less” Ion Channel

An unusual mechanism of ion channel regulation generates voltage-dependent gating in the absence of a canonical voltage-sensing domain

Integrated Genomic Analysis Implicates Haploinsufficiency of Multiple Chromosome 5q31.2 Genes in De Novo Myelodysplastic Syndromes Pathogenesis

Deletions spanning chromosome 5q31.2 are among the most common recurring cytogenetic abnormalities detectable in myelodysplastic syndromes (MDS). Prior genomic studies have suggested that haploinsufficiency of multiple 5q31.2 genes may contribute to MDS pathogenesis. However, this hypothesis has never been formally tested. Therefore, we designed this study to systematically and comprehensively evaluate all 28 chromosome 5q31.2 genes and directly test whether haploinsufficiency of a single 5q31.2 gene may result from a heterozygous nucleotide mutation or microdeletion. We selected paired tumor (bone marrow) and germline (skin) DNA samples from 46 de novo MDS patients (37 without a cytogenetic 5q31.2 deletion) and performed total exonic gene resequencing (479 amplicons) and array comparative genomic hybridization (CGH). We found no somatic nucleotide changes in the 46 MDS samples, and no cytogenetically silent 5q31.2 deletions in 20/20 samples analyzed by array CGH. Twelve novel single nucleotide polymorphisms were discovered. The mRNA levels of 7 genes in the commonly deleted interval were reduced by 50% in CD34+ cells from del(5q) MDS samples, and no gene showed complete loss of expression. Taken together, these data show that small deletions and/or point mutations in individual 5q31.2 genes are not common events in MDS, and implicate haploinsufficiency of multiple genes as the relevant genetic consequence of this common deletion

Agroecology and Health: Lessons from Indigenous Populations.

Purpose of reviewThe article aims to systematize and disseminate the main contributions of indigenous ancestral wisdom in the agroecological production of food, especially in Latin America. For this purpose, it is necessary to ask whether such knowledge can be accepted by academia research groups and international forums as a valid alternative that could contribute to overcome the world's nutritional problems.Recent findingsAlthough no new findings are being made, the validity of ancestral knowledge and agroecology is recognized by scientific research, and by international forums organized by agencies of the United Nations. These recommend that governments should implement them in their policies of development, and in the allocation of funds to support these initiatives. Agroecology and ancestral knowledge are being adopted by a growing number of organizations, indigenous peoples and social groups in various parts of the world, as development alternatives that respond to local needs and worldviews. Its productive potential is progressively being recognized at an international level as a model that contributes to improve the condition of people regarding nutritional food

Depressed mood in pregnancy: Prevalence and correlates in two Cape Town peri-urban settlements

<p>Abstract</p> <p>Background</p> <p>The disability associated with depression and its impact on maternal and child health has important implications for public health policy. While the prevalence of postnatal depression is high, there are no prevalence data on antenatal depression in South Africa. The purpose of this study was to determine the prevalence and correlates of depressed mood in pregnancy in Cape Town peri-urban settlements.</p> <p>Methods</p> <p>This study reports on baseline data collected from the Philani Mentor Mothers Project (PMMP), a community-based, cluster-randomized controlled trial on the outskirts of Cape Town, South Africa. The PMMP aims to evaluate the effectiveness of a home-based intervention for preventing and managing illnesses related to HIV, TB, alcohol use and malnutrition in pregnant mothers and their infants. Participants were 1062 pregnant women from Khayelitsha and Mfuleni, Cape Town. Measures included the Edinburgh Postnatal Depression Scale (EPDS), the Derived AUDIT-C, indices for social support with regards to partner and parents, and questions concerning socio-demographics, intimate partner violence, and the current pregnancy. Data were analysed using bivariate analyses followed by logistic regression.</p> <p>Results</p> <p>Depressed mood in pregnancy was reported by 39% of mothers. The strongest predictors of depressed mood were lack of partner support, intimate partner violence, having a household income below R2000 per month, and younger age.</p> <p>Conclusions</p> <p>The high prevalence of depressed mood in pregnancy necessitates early screening and intervention in primary health care and antenatal settings for depression. The effectiveness and scalability of community-based interventions for maternal depression must be developed for pregnant women in peri-urban settlements.</p> <p>Trial registration</p> <p>ClinicalTrials.gov: <a href="http://www.clinicaltrials.gov/ct2/show/NCT00972699">NCT00972699</a>.</p