Technological properties of Lactobacillus fermentum involved in the processing of dolo and pito, West African sorghum beers, for the selection of starter cultures

Aim: Technological properties of Lactobacillus fermentum isolates involved in spontaneous fermentation of dolo and pito wort were examined to select starter cultures. Methods and Results: 264 isolates were screened for antimicrobial activity, acidifying activity, exopolysaccharides (EPSs) and amylase production. An antimicrobial activity was detected for 33·3%, 31·8%, 22·7% and 15·9% of the isolates towards Staphylococcus aureus enterotoxin A producer, Staphylococcus aureus enterotoxin A and B producer, Escherichia coli and Listeria innocua, respectively. A similarity was found between the isolates which were clustered in four groups according to their rates of acidification of sorghum malt broth. The faster acidifying group of isolates (43·48%) had a rate of acidification evaluated as ΔpH of 1·14 ± 0·15 pH unit after 6 h of fermentation, followed by a second group of isolates (38·08%) with a similar rate of acidification after 9 h of fermentation. From the isolates endowed with an antimicrobial activity, 5·76% belonged to the faster acidifying group and 40·38% belonged to the second group. 88·7% of the isolates had the ability for producing EPSs but not amylase. Conclusion: Lactobacillus fermentum ferments dolo and pito wort by lowering the pH and providing organic acids, EPSs and antimicrobial compounds. Significance and Impact of the Study: Strains with a rapid rate of acidification, an antimicrobial activity and producing EPSs are suggested to have potential for starter cultures.     

The origins of music in auditory scene analysis and the roles of evolution and culture in musical creation

Whether music was an evolutionary adaptation that conferred survival advantages or a cultural creation has generated much debate. Consistent with an evolutionary hypothesis, music is unique to humans, emerges early in development and is universal across societies. However, the adaptive benefit of music is far from obvious. Music is highly flexible, generative and changes rapidly over time, consistent with a cultural creation hypothesis. In this paper, it is proposed that much of musical pitch and timing structure adapted to preexisting features of auditory processing that evolved for auditory scene analysis (ASA). Thus, music may have emerged initially as a cultural creation made possible by preexisting adaptations for ASA. However, some aspects of music, such as its emotional and social power, may have subsequently proved beneficial for survival and led to adaptations that enhanced musical behaviour. Ontogenetic and phylogenetic evidence is considered in this regard. In particular, enhanced auditory–motor pathways in humans that enable movement entrainment to music and consequent increases in social cohesion, and pathways enabling music to affect reward centres in the brain should be investigated as possible musical adaptations. It is concluded that the origins of music are complex and probably involved exaptation, cultural creation and evolutionary adaptation.     

基于净生产力生态足迹模型的工业碳排放效应、影响因素与情景模拟

以不同类型城市东营和滨州为例,采用基于净生产力的生态足迹模型测度2005—2014年两市工业碳排放效应,利用弹性系数模型对工业碳排放生态足迹及其影响因素进行对比,通过情景模拟分析了基准和低碳情景下两市的可持续低碳发展潜力。研究结果显示:(1)东营碳排放总量和碳排放强度明显高于滨州,两市的碳排放生态足迹总体上都处于上升趋势,年均增长率分别为12.79%和6.16%,这与两市工业化发展阶段不同有关;(2)2005—2008、2008—2011和2011—2014,东营工业碳排放生态足迹当量主导影响因素组合变化为"耕地面积-土地城镇化率-能源结构系数"转化为"耕地面积-人口规模-能源结构系数"到"耕地面积-人口规模-第二产业比重";滨州2005—2014年的主导因素组合一直为"人口规模-土地城镇化率-能源结构系数";(3)通过情景模拟分析2020年东营、滨州的低碳发展潜力:基准和低碳情景下,滨州生态赤字分别为东营的10倍和2.6倍;就"减排"潜力而言,滨州远远高于东营,但实现低碳情景是工业GDP增长从现阶段20.6%骤降到6.5%为代价,对产业结构调整升级要求很高。对东营而言,低碳情景的实现不仅要将能源利用效率提高一倍,更要保证大量重要"碳汇"资源的恢复与重建。     

Diet selectivity in a terrestrial forest invertebrate,the Auckland tree wētā, across three habitat zones

Insects are important but overlooked components of forest ecosystems in New Zealand. For many insect species, information on foraging patterns and trophic relationships is lacking. We examined diet composition and selectivity in a large‐bodied insect, the Auckland tree wētā Hemideina thoracica, in three habitat zones in a lowland New Zealand forest. We asked whether H. thoracica selectively forage from available plant food sources, and whether these choices were lipid‐rich compared to nonpreferred available plants. We also identified the proportion of invertebrates in their frass as a proxy for omnivory. From reconnaissance plot sampling, together with fecal fragment analysis, we report that more than 93% of individual tree wētā had eaten invertebrates before capture. Additionally, wētā in the highest elevation hillslope habitat zone consumed significantly fewer species of plants on average than wētā on the low‐elevation terrace habitat. Upper hillslope wētā also had the highest average number of invertebrate fragments in their frass, significantly more than wētā in the low‐elevation terrace habitat zone. Wētā showed high variability in the consumption of fruit and seeds across all habitat zones. Generally, we did not observe diet differences between the sexes (although it appears that male wētā in the mid‐hillslope habitat ate fruits and seeds more voraciously than females), suggesting that the sexes have similar niche breadths and display similar degrees of omnivorous behavior. Extraction of leaf lipids demonstrated a range of lipid content values in available plants, and Ivlev's Electivity Index indicated that plant species which demonstrated high electivity tended to have higher concentrations of lipids in their leaves. Our findings indicate that H. thoracica forage omnivorously and selectively, and hence play multiple roles in native ecosystems and food webs.     

干旱地区生态-生产-生活承载力变化情势与演变情景分析

干旱地区实现可持续发展的重要途径在于协调生态系统、生产系统和生活系统三者之间的关系,提高生态承载力、生产承载力和生活承载力,促进三大系统和谐高效运行。以干旱地区塔里木河下游尉犁地区为例,探讨了生态-生产-生活系统承载力的基本内涵及其相互作用的基本特点,选取生态-生产-生活系统承载力的综合测度指标,采用状态空间的理想点法求解出生态-生产-生活系统承载力的理想状态值和实际指数值,综合评估了生态-生产-生活系统承载力的现状情势,进而采用多模型互补对接支持下的系统动力学模型预测未来30a塔里木河下游尉犁地区生态-生产-生活承载力变化的总体变化情景。结果认为,在不同生活水平下的塔里木河下游生态-生产-生活承载力目前均处于超载状态,干旱脆弱的生态环境严重制约着生态承载力的提高,经济发展水平低下限制着生产系统承载力的提升,人口素质和生活质量低下成为制约生活承载力提高的长期因素,但未来30a生态-生产-生活承载力的整体超载状况将趋于缓解,自2009年起的整体承载力将处于可载状态,居民生活水平有望达到小康标准,到2054年以后在可载状态下居民生活水平有望达到富裕和现代化标准,但尚须做数百年的长期努力。     

Natural environment statistics in the upper and lower visual field are reflected in mouse retinal specializations

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The Seasonal Occurrence of Glass Eels (Anguilla Anguilla L.) in the Rio Minho between 1991 and 1993 (North of Portugal)

Glass eels were sampled monthly at two stations in the Rio Minho. The experimental fishery was carried out in the estuary between November 1991 and July 1992 and at an upstream site between December 1991 and March 1993. The yield differed at each station, especially in summer and between the official seasons of the experimental glass eel fishery. Early pigmentation stages were more frequent in the estuary and the maximum lengths and weights were observed in autumn and winter. The official statistics of the professional glass eel fishery are briefly mentioned.     

Physiological stress in volcano rabbit Romerolagus diazi populations inhabiting contrasting zones at the Corredor Biologico Chichinautzin,Mexico

Changes in the environment are a common factor as human populations continue to increase. Wild mammals face these changes even in those places where they live under protection because protected areas borders are not hermetic. Measurements of faecal cortisol metabolites have become a useful tool for monitoring animal physiological status as they reflect stressful situations. In this study we measured faecal cortisol metabolites in volcano rabbits, Romerolagus diazi, inhabiting a natural protected area. Concentrations were compared between animals inhabiting disturbed vs. more natural sites within the general zone. Not only were faecal cortisol metabolites levels significantly higher in animals from the disturbed sites indicating potentially higher physiological stress intensities, but there was larger variation between the concentrations measured in those samples as well. These inter-individual cortisol metabolites concentrations are a potential indicator of physiological health for wildlife.     

The feeding strategy of the dunlin (Calidris alpina L.) in artificial and non-artificial habitats at Ria de Aveiro,Portugal

Usually waders (Aves, Charadrii) feed in the inter-tidal zone over the low tide period and roost over high tide. But occasionally when their energetic needs increase, due to adverse weather conditions or to a need to store fat to fuel migration, the birds also feed during high tide, sometimes in agricultural land. At the Ria de Aveiro, about 44% (corresponding to 4500 birds) of the wintering dunlin (Calidris alpina) use artificial salt pan habitats throughout the winter whilst the others utilize natural intertidal habitats, mainly mudflats. The dunlin that feed intertidally in natural areas, such as the Canal de Mira, do not feed over high tide. In contrast, the birds that use the salt pan area feed both during low tide, in abandoned salt pans whose walls are breached and thus allow access to the tide, and high tide, in active salt pans, and keep on doing so throughout the winter. The energetic needs of both groups of birds are thought to be similar. However, the benthos of the abandoned salt pans seem to be different, and poorer in energetic terms, from those of the natural mudflats. It is argued that dunlin wintering in the salt pan area must compensate for this by feeding over high tide in active salt pans. Rather than just being a means of obtaining more energy at certain times of high energy demand, it would seem that feeding in active salt pans over high tide should be considered as a normal component of the feeding strategy of these birds, a strategy that is different from those wintering in the natural mudflats. These findings highlight the importance of the salt exploitation industry to waders and also show that artificial habitats can support large numbers of wintering waders.     

Causes of low vision and major low-vision devices prescribed in the low-vision clinic of Nepal Eye Hospital,Nepal

Visual impairment is a major public health problem. Identifying the main causes of low vision and the major low-vision devices prescribed will help to develop and implement the low-vision rehabilitation service. We find out the causes of low vision and the low-vision devices prescribed in the low-vision clinic of Nepal Eye Hospital. A retrospective cross-sectional review of all patients attending the low-vision clinic from 1 May 2009 to 31 April 2011. Patients having visual acuity less than 3/60 in the better eye with best refractive correction were excluded. Of the 137?patients, the mean age was 32.53?±?22.90?years; 71.5% were male and 67.88% were under 40. The major causes of low vision were nystagmus (30.70%), high refractive error (22.62%), cataract (15.30%), retinitis pigmentosa (15.30%) and age-related macular degeneration (13.10%); 78.10% patents were wearing glasses while telescopes were prescribed for 29.20% patients. Nystagmus, high refractive error and cataract are the main causes of low vision in Nepal. The majority of the low-vision patients seen in this clinic are of working age. Telescopes are the major low-vision device prescribed. We review approach the cause of low-vision problem in low-vision clinic Nepal Eye Hospital, Nepal.     

A novel method for the biosynthesis of deuterated proteins with selective protonation at the aromatic rings of Phe,Tyr and Trp

A novel biosynthetic strategy is described for the preparation of deuterated proteins containing protons at the ring carbons of Phe, Tyr and Trp, using the aromatic amino acid precursor shikimic acid. Specific protonation at aromatic side chains, with complete deuteration at C^/positions was achieved in proteins overexpressed in bacteria grown in shikimate-supplemented D₂O medium. Co-expression of a shikimate transporter in prototrophic bacteria resulted in protonation levels of 62–79%, whereas complete labeling was accomplished using shikimate auxotrophic bacteria. Our labeling protocol permits the measurement of important aromatic side chain derived distance restraints in perdeuterated proteins that could be utilized to enhance the accuracy of NMR structures calculated using low densities of NOEs from methyl selectively protonated samples.     

Geographic disparities of breast cancer incidence in Portugal at the district level: A spatial age-period-cohort analysis, 1998-2011

BackgroundBreast cancer is the most common malignancy in women world-wide and the most common cause of cancer deaths, which can often be managed with early diagnosis and subsequent treatment. Here, we focus on geographic disparities in incidence within Portugal for three age groups of women (30−49; 50−69; 70−84 years).MethodsAge-period-cohort (APC) models are widely used in cancer surveillance, and these models have recently been extended to allow spatially-varying effects. We apply novel spatial APC models to estimate relative risk and age-adjusted temporal trends at the district level for the 20 districts in Portugal. Our model allows us to report on country-wide trends, but also to investigate geographic disparities between districts and trends within districts.ResultsAge-adjusted breast cancer incidence was increasing over 1998–2011 for all three age groups and in every district in Portugal. However, we detect spatially-structured between-district heterogeneity in relative risk and age-adjusted trends (Net Drifts) for each of the three age groups, which is most pronounced in the highly-screened (50−69yo) and late-onset (70−84yo) groups of women.ConclusionsWe present evidence of disparities in breast cancer incidence at a more granular geographic level than previously reported. Some disparities may be due to latent risk factors, which cannot be accounted for by age, birth year, and geographic location alone.ImpactOur study motivates resuming data collection for breast cancer incidence at the district level in Portugal, as well as the study of exogenous risk factors.     

Phylogenetic status and matrilineal structure of the biting midge, Culicoides imicola, in Portugal, Rhodes and Israel

The biting midge Culicoides imicola Kieffer (Diptera: Ceratopogonidae) is the most important Old World vector of African horse sickness (AHS) and bluetongue (BT). Recent increases of BT incidence in the Mediterranean basin are attributed to its increased abundance and distribution. The phylogenetic status and genetic structure of C. imicola in this region are unknown, despite the importance of these aspects for BT epidemiology in the North American BT vector. In this study, analyses of partial mitochondrial cytochrome oxidase subunit I gene (COI) sequences were used to infer phylogenetic relationships among 50 C. imicola from Portugal, Rhodes, Israel, and South Africa and four other species of the Imicola Complex from southern Africa, and to estimate levels of matrilineal subdivision in C. imicola between Portugal and Israel. Eleven haplotypes were detected in C. imicola, and these formed one well-supported clade in maximum likelihood and Bayesian trees implying that the C. imicola samples comprise one phylogenetic species. Molecular variance was distributed mainly between Portugal and Israel, with no haplotypes shared between these countries, suggesting that female-mediated gene flow at this scale has been either limited or non-existent. Our results provide phylogenetic evidence that C. imicola in the study areas are potentially competent AHS and BT vectors. The geographical structure of the C. imicola COI haplotypes was concordant with that of BT virus serotypes in recent BT outbreaks in the Mediterranean basin, suggesting that population subdivision in its vector can impose spatial constraints on BT virus transmission.     

Modelling spatial and environmental effects at the edge of the distribution: the red-backed shrike Lanius collurio in Northern Portugal

This study examined the interplay of spatial and environmental effects shaping the range margin of the red‐backed shrike (Lanius collurio) in northern Portugal. The occurrence of shrikes in 10 × 10 km UTM squares was related to three sets of explanatory variables, reflecting environmental effects (climate and habitat), large‐scale spatial trends, and neighbourhood influences (considering an autologistic term); spatial variables were used as surrogates for historical and demographic factors. Multiple logistic regression models were built for each set, and then variation partitioning based on partial regressions isolated the unique and shared components of explained variation. The environmental model revealed a dominant influence of climate effects, with the occurrence of shrikes increasing with frost and thermal amplitude, declining with insolation, and responding unimodally to rainfall. There was a weaker influence of habitat conditions, though shrikes were more likely with increasing cover by annual crops and pastures, and decreasing forest cover. Only a relatively small proportion of explained variation was due to a ‘pure’ environmental component (10.4%), as most variation explained by environmental factors appeared spatially structured (51.9%). The unique contributions of spatial variables to the overall model were also small, though the neighbourhood effects appeared relatively stronger than large‐scale trends. Taken together, results suggested that the south‐western range margin of the red‐backed shrike was largely determined by spatially structured environmental factors. Nevertheless, there were also ‘pure’ environmental factors determining some isolate occurrences irrespective of any spatial structure, and ‘pure’ spatial factors that appeared to favour the occupation of squares surrounding the core distribution areas irrespective of environmental conditions. These results add to the growing evidence that both environmental and spatial factors need to be considered in predictive modelling of species range margins.     

Airborne pollen concentration in the region of Braga, Portugal, and its relationship with meteorological parameters

The variation in airborne pollen concentrationof the Braga region (Portugal) was studied inspringtime, during the flowering of Vitisvinifera. The data set was obtained for twoconsecutive years (1999 and 2000), using aCour-type sampler.During this period, thirty-six taxa wereobserved in a total of 3,200 pollengrains m^-3 of air (CPA). The main pollentypes observed were Olea, Poaceaea,nd Castanea, representing 74% of thepollen spectrum.The airborne pollen concentration (CPA) wassignificantly correlated with certainmeteorological parameters. Pollen concentrationwas positively correlated with temperature andwind direction (East and Northeast) andnegatively correlated with rainfall and numberof rainy days.     

Cross-contamination in the kitchen: estimation of transfer rates for cutting boards, hands and knives

Aims: To quantify cross-contamination in the home from chicken to ready-to-eat salad. Methods and Results: Based on laboratory scenarios performed by de Jong et al. (2008) , transfer rates were estimated for Campylobacter jejuni and Lactobacillus casei as a tracer organism. This study showed that transfer characteristics for both micro-organisms were comparable when washing regimes and transfer via items (cutting board, hands and knives) were compared. Furthermore, the study showed that the use of separate transfer rates for transfer from chicken to items and from items to salad will lead to an overestimation of campylobacteriosis risk. Applying good hygienic practices resulted in final levels of bacteria in the salad below the detection limit. Our study showed that it is important to include these data points in model fitting. Conclusions: Results obtained in observational studies with Lact. casei can be translated to Camp. jejuni using the transfer rates obtained in this study. Cross-contamination by hands, cutting boards and knives was equally important. Significance and Impact of the Study: Cross-contamination should be incorporated in microbiological risk assessments. The present study contributes to this by quantifying transfer of Camp. jejuni and Lact. casei from raw chicken via various contact surfaces into the ready-to-eat product.