490 research outputs found

    Effects of exoplanetary gravity on human locomotor ability

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    At some point in the future, if mankind hopes to settle planets outside the Solar System, it will be crucial to determine the range of planetary conditions under which human beings could survive and function. In this article, we apply physical considerations to future exoplanetary biology to determine the limitations which gravity imposes on several systems governing the human body. Initially, we examine the ultimate limits at which the human skeleton breaks and muscles become unable to lift the body from the ground. We also produce a new model for the energetic expenditure of walking, by modelling the leg as an inverted pendulum. Both approaches conclude that, with rigorous training, humans could perform normal locomotion at gravity no higher than 4 gEarthg_{\textrm{Earth}}.Comment: 12 pages, 4 figures, to be published in The Physics Teache

    Facilitating the registration of biocontrol organisms, plant extracts and semiochemicals in Europe

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    The legal regulation of plant protection products (Dir. 91/414/ EEC) is a bottleneck in the market introduction of new microbial biocontrol agents, plant extracts and pheromones. In contrast, invertebrate biocontrol agents (“beneficials”) are not registered at EU level. The EU-funded project REBECA suggested improvements to accelerate the regulation process and make it more cost-effective, without compromises to the level of safety. Representatives of all stakeholder groups participated in the REBECA workshops. The EU Commission and Member States are encouraged to improve the registration of biocontrol organisms, plant extracts and semiochemicals at EU and/or national level. The full proposals can be found at www.rebeca-net.de

    The effect of deamidation and lipids on the interfacial and foaming properties of ultrafiltered oat protein concentrates

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    The aim of this study was to investigate the air-water interfacial and foaming properties of oat protein concentrates produced by an enzyme-aided ultrafiltration method with and without deamidation. A further aim was to determine the role of polar and non-polar lipids at the air-water interface and in foams. The deamidated and ultrafiltered oat protein concentrate (DE-UF-OPC) exhibited higher surface tension compared to the ultrafiltered oat protein concentrate (UF-OPC). DE-UF-OPC had a significantly higher negative zeta potential value (−50 mV) compared to the UF-OPC (−38 mV) at pH 7.0. The higher net charge of the DE-UF-OPC may have decreased the equilibrium concentration of oat proteins at the interfacial layer due to higher repulsion between them. Both of the ethanol extracted OPCs exhibited higher surface tension values most likely due to the partial denaturation of albumins and/or globulins. Removal of the majority of non-polar lipids had no effect on the equilibrium surface tension of OPCs. DE-UF-OPC and UF-OPC exhibited some, but limited foaming ability. The removal of non-polar lipids significantly improved the foamability and stability of DE-UF-OPC and UF-OPC, but the removal of polar lipids only improved the foamability of DE-UF-OPC.Peer reviewe

    Multichannel optical sensor for oil film pressure measurement in engine main bearing

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    An optical sensor has been developed for experimental determination of oil film pressure in journal bearings. The non-intrusive fibre optic sensor is integrated in the sliding surface of the bearing to measure the actual oil film pressure under load without disturbing the actual tribological contact conditions. The sensors with a multichannel system also allowed the use of several optical sensors simultaneously. Four optical sensors were integrated in a hydrodynamic journal bearing of a large scale diesel engine and the engine tests were carried out with different loads to study the sensor operation in demanding operating conditions. The oil film pressure was successfully measured and the results showed differences in bearing pressure depending on the position of the sensor and on the operating cycle of the cylinders. The optical sensor was capable to measure the oil film pressure in journal bearing with a good sensitivity and repeatability during the tests. &nbsp

    Male Attitudes towards Infertility:Results from a Global Questionnaire

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    PURPOSE: In general, men are less likely to seek health care than women. Infertility is a global disease that afflicts approximately 15% of reproductive age couples and the male contributes to 40% of the diagnosable cause. Remarkably, no large or multi-national population data exist regarding men’s perceptions about their infertility. The purpose of this study was to advance our knowledge about the infertile male’s social experience regarding: (1) how they feel about their infertility, (2) what motivated them to seek health care, (3) how likely are they to talk with others about their infertility, (4) their awareness of male infertility support groups, and (5) what their primary source for information is regarding male infertility? Based on the results from this study, these simple questions now have clearer definition. MATERIALS AND METHODS: An Institutional Review Board-approved, male-directed, anonymous questionnaire translated into 20 languages was made globally available through the Fertility Europe website (https://fertilityeurope.eu). Males (n=1,171) age 20–49 years were invited to complete the online survey after informed consent. RESULTS: Most respondents were European (86%). Of European men, <15.8% were self-motivated to seek medical help. Further, their physician was not the primary source of information regarding their infertility. While most men (59%) viewed their infertility positively, a large majority were not very likely (73%) to talk about it. Most respondents indicated a lack of awareness or absence of male infertility support groups. CONCLUSIONS: These are the first multi-national population data revealing men’s feelings about their infertility, what motivates them to seek help and their awareness of resources for peer support and information. These findings also serve to highlight significant gaps that exist in the provision of male reproductive health care and in supportive resources for men suffering from infertility. We offer recommendations on how to address the problem(s)

    Stimulating fertility awareness: the importance of getting the language right

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    While education about fertility is not intrinsically controversial, finding the right language to communicate the topic can be challenging, as there are several risks of unintended negative effects such as dissonance, anxiety, culpability, and stigma due to social norming. In this article, we share some of our learnings from promoting fertility awareness in the hope that they will inspire further debate and research on this topic. Starting from the ethical principles of respect for reproductive autonomy, avoiding harm (in terms of stigma or anxiety) and inclusivity, we have formulated five recommendations: (i) frame fertility awareness messages with (reproductive) autonomy in mind and aim to be inclusive of those who do not represent the traditional nuclear family; (ii) be empathetic and steer clear of blame; (iii) avoid scaremongering and offer a positive angle; (iv) give due consideration to both women and men in fertility health messaging; and (v) tailor the messages to particular contexts and audiences and develop resources in close collaboration with the target groups

    Carriership of two copies of C9orf72 hexanucleotide repeat intermediate-length alleles is a risk factor for ALS in the Finnish population

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    The hexanucleotide repeat expansion in intron 1 of the C9orf72 gene causes amyotrophic lateral sclerosis (ALS) and frontotemporal dementia. In addition to the effects of the pathogenic expansion, a role of intermediate-length alleles has been suggested in ALS, corticobasal degeneration and Parkinson's disease. Due to the rarity of intermediate-length alleles with over 20 repeats and the geographical variability in their frequency, large studies that account for population stratification are needed to elucidate their effects. To this aim, we used repeat-primed PCR and confirmatory PCR assays to determine the C9orf72 repeat allele lengths in 705 ALS patients and 3958 controls from Finland. After exclusion of expansion carriers (25.5% of the ALS patients and 0.2% of the controls), we compared the frequency of intermediate-length allele carriers of 525 ALS cases and 3950 controls using several intermediate-length allele thresholds (7-45, 17-45, 21-45, 24-45 and 24-30). The carriership of an intermediate-length allele did not associate with ALS (Fisher's test, all p >= 0.15) nor was there any association with survival (p >= 0.33), when we divided our control group into three age groups (18-65, 66-84 and 85-105 years). Carriership of two intermediate-length alleles was associated with ALS, when the longer allele was >= 17 repeats (p=0.002, OR 5.32 95% CI 2.02-14.05) or >= 21 repeats (p=0.00016, OR 15.21 95% CI 3.79-61.0). Our results show that intermediate-length alleles are a risk factor of ALS when present in both alleles, whereas carrying just one intermediate-length allele was not associated with ALS or survival.Peer reviewe

    Energy wood production from private forests -nonindustrial private forest owners&apos; perceptions and attitudes in Croatia and Serbia

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    a b s t r a c t Private forests in Croatia and Serbia are highly fragmented in small plots with low productivity and owned by a large number of small-scale nonindustrial private forest owners (NIPFs). The study conducted surveys among 232 NIPFs in these two countries to find out their perceptions and attitudes related to energy wood production from their forests. The secondary objective of the study was to provide policy recommendations to the public authorities and professionals in these countries for improving the preconditions for energy wood mobilization from private forests. The study found that the NIPFs perceived underdeveloped market and low price for energy wood, absence of favorable policies, fragmented forests properties, older NIPFs&apos; lack of interests in energy wood production, and difficulties in getting bank loan for energy wood related business activities as barriers against energy wood production from private forests. However, the NIPFs showed positive attitudes towards producing energy wood from their forests and they considered the possibilities of creating new jobs and commercial opportunities as strengths of energy wood production. The NIPFs&apos; socio-demographic background had statistically significant relations with their perceptions and attitudes related to energy wood production. The dimensions of the NIPFs&apos; perceptions and attitudes related to energy wood production showed two key dimensions -institutionalists and enthusiasts. The variables to explain the NIPFs&apos; attitudes to energy wood production were different between the two countries and they indicated the differences in the country level circumstances for energy wood production. The results appeared to be relevant for understanding the issues that the NIPFs perceived as barriers against developing a viable energy wood market in their countries. When new forestry institutions and policies are emerging in these countries, the existing public and private forestry institutions need to play an important role for improving the preconditions for energy wood production from private forests
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