Effect of ocean acidification on the structure and fatty acid composition of a natural plankton community in the Baltic Sea

Increasing atmospheric carbon dioxide (CO2) is changing seawater chemistry towards reduced pH, which consequently affects various properties of marine organisms. Coastal and brackish water communities are expected to be less affected by ocean acidification (OA) as these communities are typically adapted to high fluctuations in CO2 and pH. Here we investigate the response of a coastal brackish water plankton community to increasing CO2 levels as projected for the coming decades and the end of this century in terms of community and biochemical fatty acid (FA) composition. A Baltic Sea plankton community was enclosed in a set of off-shore mesocosms and subjected to a CO2 gradient ranging from natural concentrations (~347 μatm pCO2) up to values projected for the year 2100 (~1333 μatm pCO2). We show that the phytoplankton community composition was resilient to CO2 and did not diverge between the treatments. Seston FA composition was influenced by community composition, which in turn was driven by silicate and phosphate limitation in the mesocosms, and showed no difference between the CO2 treatments. These results suggest that CO2 effects are dampened in coastal communities that already experience high natural fluctuations in pCO2. Although this coastal plankton community was tolerant to high pCO2 levels, hypoxia and CO2 uptake by the sea can aggravate acidification and may lead to pH changes outside the currently experienced range for coastal organisms

Улучшенные модели оценки радиационного риска для отдельных когорт пациентов в Швеции

In radiological diagnostics and therapy, it is important that practitioners, referrers, (i.e. radiologists, radiation oncologists and others in health-care) are aware of how much radiation a patient may receive from the various procedures used and associated health risk. The profession has a duty to inform patients or their representatives of the advantages and disadvantages of specific investigations or treatment plans. The need to estimate and communicate risks in connection with medical use of ionizing radiation is highlighted e.g. in the Russian Federation State Law No 3, §17.2,1996 and in the EU directive (2013/59/EURATOM 2014). The most commonly used way to express harm in relation to low doses of ionizing radiation is use of the quantity effective dose (E). Effective dose, a radiation protection quantity, however is not intended to provide risk estimates for medical exposures. Its purpose is to optimize conditions for radiation workers (18-65 years) or the general public; all groups with age distributions that differ from patients. In this paper the lifetime attributable risk was used to estimate the excess risk of receiving and dying of radiogenic cancer. The lifetime attributable risk estimations are generated from three different variables, gender, attained age and age at exposure giving the possibility to create age and gender specific cancer risk estimations. Initially, the US Environmental Protection Agency lifetime attributable risk coefficients which are intended to predict the cancer risk from ionizing radiation to a normal US population were applied. In this work, the lifetime attributable risk predictions were modified to the normal Swedish population and to cohorts of Swedish patients undergoing radiological and nuclear medicine examinations or treatments with survival times that differfrom the normal population. For Swedish males, all organs were given the same absorbed dose, exposed at 20, 40 and 70 years, the lifetime attributable risk coefficients (Gy-1) were 0.11, 0.068, and 0.038, respectively, which is lower than the corresponding figures for US males, 0.13, 0.077, and 0.040. For Swedish females, all organs were given the same absorbed dose, exposed at 40 years of age with a diagnosis of breast, colon or liver cancer, the lifetime attributable risk coefficients are 0.064, 0.034, and 0.0038, respectively, which is much lower than if a 40 years female without known cancer is exposed, 0.073.В лучевой диагностике и терапии крайне важно, чтобы медицинский персонал (врачи-рентгенологи, лечащие врачи, радиационные онкологи и пр.) имели представление о том, какую дозу облучения получил пациент от различных рентгенорадиологических исследований и с каким риском для здоровья эта доза связана. Медицинский персонал несет ответственность за информирование пациентов и их законных представителей о достоинствах и недостатках выбранных исследований или планов лечения. Так, например, необходимость оценки и коммуникации рисков в контексте использования ионизирующего излучения в медицине особо отмечена в Федеральном законе ФЗ-3 «О радиационной безопасности населения» в Россйской Федерации и в директиве Евросоюза 2013/59/EURATOM 2014. Наиболее распространенным способом выражения вреда от низких доз ионизирующего излучения является использование эффективной дозы, которая, хотя и является основной величиной в радиационной защите, не предназначена для оценки рисков от медицинского облучения. Ее задачей является обеспечение оптимизации радиационной защиты персонала (людей в возрасте 18—65лет) и населения — групп с возрастным распределением, резко отличающимся от возрастных распределений пациентов. В данном исследовании величина пожизненного атрибутивного риска была использована для оценки избыточного риска получить и умереть от радиогенного рака различной нозологии. Оценки значений пожизненного атрибутивного риска основывались на трех переменных: пол, возраст дожития и возраст при облучении, что позволило определить риски развития радиогенного рака с учетом пола и возраста пациентов. Изначально были использованы коэффициенты пожизненного атрибутивного риска, разработанные Агентством по защите окружающей среды США, которые позволяют оценить избыточные радиогенные раки для нормальной популяции США. В данной работе значения коэффициентов пожизненного атрибутивного риска были изменены с учетом специфики здорового шведского населения, а также когорт шведских пациентов, проходящих различные рентгенорадиологические исследования и курсы лучевой терапии, время дожития которых существенно отличалось от такового для обычного населения. Для шведских мужчин, при условии, что все органы организма получили одну и ту же поглощенную дозу и облучение произошло в возрасте 20, 40 и 70 лет, соответствующие коэффициенты пожизненного атрибутивного риска (Гр-1) составили 0,11, 0,068, и 0,038 соответственно, что ниже по сравнению с аналогичными данными для американских мужчин — 0,13, 0,077, и 0,040 соответственно. Для шведских женщин, при условии, что все органы организма получили одну поглощенную дозу и облучение произошло в возрасте 40 лет с диагнозом рака груди, прямой кишки или печени, коэффициенты пожизненного атрибутивного риска (Гр-1) составили 0,064, 0,034, и 0,0038 соответственно, что существенно ниже значения 0,073 в случае облучения 40-летних женщин, у которых диагноз рака установлен не был

The Radial Structure of the Cygnus Loop Supernova Remnant --- Possible evidence of a cavity explosion ---

We observed the North-East (NE) Limb toward the center region of the Cygnus Loop with the ASCA Observatory. We found a radial variation of electron temperature (kTe) and ionization timescale (log(\tau)) whereas no variation could be found for the abundances of heavy elements. In this paper, we re-analyzed the same data set and new observations with the latest calibration files. Then we constructed the precise spatial variations of kTe, log(\tau), and abundances of O, Ne, Mg, Si, and Fe over the field of view (FOV). We found a spatial variation not only in kTe and in log(\tau) but also in most of heavy elements. As described in Miyata et al. (1994), values of kTe increase and those of log(\tau) decrease toward the inner region. We found that the abundance of heavy elements increases toward the inner region. The radial profiles of O, Ne, and Fe show clear jump structures at a radius of 0.9 Rs, where Rs is the shock radius. Outside of 0.9 Rs, abundances of all elements are constant. On the contrary, inside of 0.9 Rs, abundances of these elements are 20--30 % larger than those obtained outside of 0.9 Rs. The radial profile of kTe also shows the jump structure at 0.9 Rs. This means that the hot and metal rich plasma fills the volume inside of 0.9 Rs. We concluded that this jump structure was the possible evidence for the pre-existing cavity produced by the precursor. If the ejecta fills inside of 0.9 Rs, the total mass of the ejecta was roughly 4\Msun. We then estimated the main-sequence mass to be roughly 15\Msun, which supports the massive star in origin of the Cygnus Loop supernova remnant and the existence of a pre-existing cavity.Comment: 37 pages, 14 figures. Accepted for publication of Ap

A pathway to identifying and valuing cultural ecosystem services: an application to marine food webs

Beyond recreation, little attention has been paid thus far to economically value Cultural Ecosystem Services (CESs), especially in the context of coastal or marine environment. This paper develops and tests a pathway to the identification and economic valuation of CESs. The pathway enables researchers to make more explicit, and to economically value, cultural dimensions of environmental change. We suggest that the valuation process includes a simultaneous development of the scenarios of environmental change including related biophysical impacts, and a documentation of culture-environment linkages. A well-defined ecosystem service typology is also needed to classify cultural-ecological linkages as specific CESs. The pathway then involves the development of detailed, multidimensional depictions of the culture-environment linkages for use in a stated preference survey. The anticipated CES interpretations should be confirmed through debriefing questions in the survey questionnaire. The proposed approach is demonstrated with a choice experiment-based case study in Turkey that focuses improvements to the food web of the Black Sea. The results of this study indicate that economic preferences for CESs other than recreation can be estimated in a way that is economically consistent using the proposed approach

Moving back: The radiation dose received from lumbar spine quantitative fluoroscopy compared to lumbar spine radiographs with suggestions for dose reduction

Purpose: Quantitative fluoroscopy is an emerging technology for assessing continuous inter-vertebral motion in the lumbar spine, but information on radiation dose is not yet available. The purposes of this study were to compare the radiation dose from quantitative fluoroscopy of the lumbar spine with lumbar spine radiographs, and identify opportunities for dose reduction in quantitative fluoroscopy. Methods: Internationally reported dose area product (DAP) and effective dose data for lumbar spine radiographs were compared with the same for quantitative fluoroscopy and with data from a local hospital for functional radiographs (weight bearing AP, lateral, and/or flexion and extension) (n = 27). The effects of procedure time, age, weight, height and body mass index on the fluoroscopy dose were determined by multiple linear regression using SPSS v19 software (IBM Corp., Armonck, NY, USA). Results and conclusion: The effective dose (and therefore the estimated risk) for quantitative fluoroscopy is 0.561 mSv which is lower than in most published data for lumbar spine radiography.The dose area product (DAP) for sagittal (flexion + extension) quantitative fluoroscopy is 3.94 Gy cm2 which is lower than local data for two view (flexion and extension) functional radiographs (4.25 Gy cm2), and combined coronal and sagittal dose from quantitative fluoroscopy (6.13 Gy cm2) is lower than for four view functional radiography (7.34 Gy cm2).Conversely DAP for coronal and sagittal quantitative fluoroscopy combined (6.13 Gy cm2) is higher than that published for both lumbar AP or lateral radiographs, with the exception of Nordic countries combined data.Weight, procedure time and age were independently positively associated with total dose, and height (after adjusting for weight) was negatively associated, thus as height increased, the DAP decreased. © 2014 The College of Radiographers

Two Dimensional Window Exchange Umbrella Sampling for Transmembrane Helix Assembly

The method of window exchange umbrella sampling molecular dynamics (WEUSMD) with a pre-optimized parameter set was recently used to obtain the most probable conformations and the energetics of transmembrane (TM) helix assembly of a generic TM sequence. When applied to glycophorin A TM domain (GpA-TM) using the restraint potentials along the helix-helix distance, however, tight interfacial packing of GpA-TM resulted in insufficient conformational sampling at short helix-helix separation. This sampling issue is addressed by extending the WEUSMD into two dimensions with the restraint potentials along the helix-helix distance and crossing angle. The two-dimensional WEUSMD results demonstrate that the incomplete sampling in the one-dimensional WEUSMD arises from high barriers along the crossing angle between the GpA-TM helices. Together with the faster convergence in both the assembled conformations and the potential of mean force, the 2D-WEUSMD can be a general and efficient approach in computational studies of TM helix assembly

Studies of Metabolic Phenotypic Correlates of 15 Obesity Associated Gene Variants

Genome-wide association studies have identified novel BMI/obesity associated susceptibility loci. The purpose of this study is to determine associations with overweight, obesity, morbid obesity and/or general adiposity in a Danish population. Moreover, we want to investigate if these loci associate with type 2 diabetes and to elucidate potential underlying metabolic mechanisms.15 gene variants in 14 loci including TMEM18 (rs7561317), SH2B1 (rs7498665), KCTD15 (rs29941), NEGR1 (rs2568958), ETV5 (rs7647305), BDNF (rs4923461, rs925946), SEC16B (rs10913469), FAIM2 (rs7138803), GNPDA2 (rs10938397), MTCH2 (rs10838738), BAT2 (rs2260000), NPC1 (rs1805081), MAF (rs1424233), and PTER (rs10508503) were genotyped in 18,014 middle-aged Danes.Five of the 15 gene variants associated with overweight, obesity and/or morbid obesity. Per allele ORs ranged from 1.15-1.20 for overweight, 1.10-1.25 for obesity, and 1.41-1.46 for morbid obesity. Five of the 15 variants moreover associated with increased measures of adiposity. BDNF rs4923461 displayed a borderline BMI-dependent protective effect on type 2 diabetes (0.87 (0.78-0.96, p = 0.008)), whereas SH2B1 rs7498665 associated with nominally BMI-independent increased risk of type 2 diabetes (1.16 (1.07-1.27, p = 7.8×10(-4))).Associations with overweight and/or obesity and measures of obesity were confirmed for seven out of the 15 gene variants. The obesity risk allele of BDNF rs4923461 protected against type 2 diabetes, which could suggest neuronal and peripheral distinctive ways of actions for the protein. SH2B1 rs7498665 associated with type 2 diabetes independently of BMI

The obesity gene, TMEM18, is of ancient origin, found in majority of neuronal cells in all major brain regions and associated with obesity in severely obese children

<p>Abstract</p> <p>Background</p> <p>TMEM18 is a hypothalamic gene that has recently been linked to obesity and BMI in genome wide association studies. However, the functional properties of TMEM18 are obscure.</p> <p>Methods</p> <p>The evolutionary history of TMEM18 was inferred using phylogenetic and bioinformatic methods. The gene's expression profile was investigated with real-time PCR in a panel of rat and mouse tissues and with immunohistochemistry in the mouse brain. Also, gene expression changes were analyzed in three feeding-related mouse models: food deprivation, reward and diet-induced increase in body weight. Finally, we genotyped 502 severely obese and 527 healthy Swedish children for two SNPs near TMEM18 (rs6548238 and rs756131).</p> <p>Results</p> <p>TMEM18 was found to be remarkably conserved and present in species that diverged from the human lineage over 1500 million years ago. The TMEM18 gene was widely expressed and detected in the majority of cells in all major brain regions, but was more abundant in neurons than other cell types. We found no significant changes in the hypothalamic and brainstem expression in the feeding-related mouse models. There was a strong association for two SNPs (rs6548238 and rs756131) of the TMEM18 locus with an increased risk for obesity (p = 0.001 and p = 0.002).</p> <p>Conclusion</p> <p>We conclude that TMEM18 is involved in both adult and childhood obesity. It is one of the most conserved human obesity genes and it is found in the majority of all brain sites, including the hypothalamus and the brain stem, but it is not regulated in these regions in classical energy homeostatic models.</p

Do Gene Variants Influencing Adult Adiposity Affect Birth Weight? A Population-Based Study of 24 Loci in 4,744 Danish Individuals

Several obesity risk alleles affecting adult adiposity have been identified by the recent wave of genome wide association studies. We aimed to examine the potential effect of these variants on fetal body composition by investigating the variants in relation to birth weight and ponderal index of the newborn.Midwife records from the Danish State Archives provided information on mother's age, parity, as well as birth weight, birth length and prematurity of the newborn in 4,744 individuals of the population-based Inter99 study. Twenty-four risk alleles showing genome-wide associations with adult BMI and/or waist circumference were genotyped. None of the 24 risk variants tested showed an association with birth weight or ponderal index after correction for multiple testing. Birth weight was divided into three categories low (≤10(th) percentile), normal (10(th)-90(th) percentile) and high birth weight (≥90th percentile) to allow for non-linear associations. There was no difference in the number of risk alleles between the groups (p = 0.57). No interactions between each risk allele and birth weight in the prediction of adult BMI were observed. An obesity risk score was created by summing up risk alleles. The risk score did not associate with fetal body composition. Moreover there was no interaction between the risk score and birth weight/ponderal index in the prediction of adult BMI.24 common variants associated with adult adiposity did not affect or interact with birth weight among Danes suggesting that the effects of these variants predominantly arise in the post-natal life

The Dispanins: A Novel Gene Family of Ancient Origin That Contains 14 Human Members

The Interferon induced transmembrane proteins (IFITM) are a family of transmembrane proteins that is known to inhibit cell invasion of viruses such as HIV-1 and influenza. We show that the IFITM genes are a subfamily in a larger family of transmembrane (TM) proteins that we call Dispanins, which refers to a common 2TM structure. We mined the Dispanins in 36 eukaryotic species, covering all major eukaryotic groups, and investigated their evolutionary history using Bayesian and maximum likelihood approaches to infer a phylogenetic tree. We identified ten human genes that together with the known IFITM genes form the Dispanin family. We show that the Dispanins first emerged in eukaryotes in a common ancestor of choanoflagellates and metazoa, and that the family later expanded in vertebrates where it forms four subfamilies (A–D). Interestingly, we also find that the family is found in several different phyla of bacteria and propose that it was horizontally transferred to eukaryotes from bacteria in the common ancestor of choanoflagellates and metazoa. The bacterial and eukaryotic sequences have a considerably conserved protein structure. In conclusion, we introduce a novel family, the Dispanins, together with a nomenclature based on the evolutionary origin