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961.
Previous analyses of hand morphology in Australopithecus afarensis have concluded that this taxon had modern human‐like manual proportions, with relatively long thumbs and short fingers. These conclusions are based on the A.L.333 composite fossil assemblage from Hadar, Ethiopia, and are premised on the ability to assign phalanges to a single individual, and to the correct side and digit. Neither assignment is secure, however, given the taphonomy and sample composition at A.L.333. We use a resampling approach that includes the entire assemblage of complete hand elements at Hadar, and takes into account uncertainties in identifying phalanges by individual, side and digit number. This approach provides the most conservative estimates of manual proportions in Au. afarensis. We resampled hand long bone lengths in Au. afarensis and extant hominoids, and obtained confidence limits for distributions of manual proportions in the latter. Results confirm that intrinsic manual proportions in Au. afarensis are dissimilar to Pan and Pongo. However, manual proportions in Au. afarensis often fall at the upper end of the distribution in Gorilla, and very lower end in Homo, corresponding to disproportionately short thumbs and long medial digits in Homo. This suggests that manual proportions in Au. afarensis, particularly metacarpal proportions, were not as derived towards Homo as previously described, but rather are intermediate between gorillas and humans. Functionally, these results suggest Au. afarensis could not produce precision grips with the same efficiency as modern humans, which may in part account for the absence of lithic technology in this fossil taxon. Am J Phys Anthropol 152:393–406, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
962.
Kimio Nishimura Momoka Suzuki Hiroki Saeki 《Bioscience, biotechnology, and biochemistry》2013,77(12):2307-2317
ABSTRACTThe optimal conditions for the preparation of glucose-conjugated chicken myofibrillar proteins (Mfs) via the Maillard reaction, presenting strong antioxidant activity against hydroxyl radicals (?OH) and high solubility in low ionic strength medium, were sought using random-centroid optimization (RCO). Four parameters of temperature, relative humidity (RH), reaction time, and glucose-to-Mfs mixing ratio, were examined, resulting in a total of 24 vertices. Evaluations were carried out relatively to each individual vertex, and the optimal preparatory conditions to obtain the highest antioxidant activity were determined as follows: temperature of 52 °C, RH of 38%, reaction time of 6.79 h, and a glucose to Mfs mixing ratio of 11.7 (w/w). The resulting glucose-conjugated chicken Mfs gained thermal gel-forming ability and its ?OH averting capacity reached 9.7 ± 0.7 μmol of gallic acid equivalent/g of protein.Abbreviations: GA: gallic acid; HORAC: hydroxyl radical averting capacity; IC50: half-maximal inhibitory concentration; 2-ME, 2-mercaptoethanol; Mfs: myofibrillar proteins; MHC: myosin heavy chain; ?OH: hydroxyl radical; PAGE: polyacrylamide gel electrophoresis; RCO: random-centroid optimization; RH: relative humidity; RLU: relative light units; SDS: sodium dodecyl sulfate; SEM: scanning electron microscope; SS: disulfide 相似文献
963.
Frida Marina Fischer Flavio Notarnicola da Silva Borges Lucia Rotenberg Maria do Rosario Dias de Oliveira Latorre Nilson Santos Soares Patricia Lima Ferreira Santa Rosa 《Chronobiology international》2013,30(6):1165-1179
This paper aims at identifying variables associated with inadequate work ability among nursing personnel at a public hospital, considering factors related to socio‐demographic, lifestyles, working conditions, and health outcomes. A cross‐sectional study was conducted in a university hospital in São Paulo, Brazil, as part of a larger research study on tolerance to 12 h night work. Nursing staff included registered nurses, nurse technicians, and nurse aides; in total, there were 996 healthcare workers (878 female; 118 male) at the time of the study. Some 696 workers (69.9%) of the population agreed to participate. Data collection (October 2004–July 2005) was based on a comprehensive questionnaire about living and working conditions (including incivility at work, work demands, work control, and support), mental and physical health symptoms (fatigue and sleep problems), and work ability. This report presents analyses of the adapted Brazilian version of the Work Ability Index (WAI) and associated variables. The study population worked one of the following shift schedules at this hospital: 12 h nights followed by 36 h off or 9 h or 6 h day (morning or afternoon) shifts. The mean age of the respondents was 34.9 (S.D.±10.4) years of age; 31.5% of the participants held two jobs. Statistical analyses using a hierarchical multiple logistic regression model were performed to evaluate the factors associated with inadequate (moderate and low scores) of the WAI. The significantly associated factors were socio‐demographic (income responsibility, sole breadwinner, raising kids, age group), working conditions (thermal discomfort, organization of the workplace, and verbal abuse), and health outcomes (high body mass index, obesity, sleep problems, and fatigue). In spite of limitations of the study design, results indicate that the nursing profession is associated with stressful working conditions, contributing to inadequate WAI. This is in addition to bad living conditions and precarious work. Intervention measures, either at the workplace or at individual levels, are necessary to prevent a decrease in work ability, even in this quite young working population. 相似文献
964.
Kazuo Miyairi Koji Fujita Toshikatsu Okuno Ko Sawai 《Bioscience, biotechnology, and biochemistry》2013,77(10):1897-1902
The electrophoretically homogeneous protein obtained from the culture filtrate of Stereum purpureum causes silver-leaf symptoms when injected into apple trees at a dosage of about 25 μg per tree. This preparation has a molecular weight of 32,000, and shows not only an endo-PG (polygalacturonase) activity, but also macerating action in several plant tissues. Toxic effects on apple trees qualitatively make parallel alteration in the endo-PG activity. From the chemical properties tested, it is suggested that the preparation differs from phytolysin reported as a toxic material inductive to silver-leaf symptoms on plum trees. 相似文献
965.
966.
国内文献提示,必须建立一套系统、科学、合理及可操作的评价指标体系来评价医疗机构科研教育能力,为此提出了基于数据包络分析的医疗机构科研教育能力综合评价的研究框架,并进一步对课题研究背景、研究目标、研究方法和预期结果作详细介绍。 相似文献
967.
采用Griffing 6×6完全双列杂交设计,对长江流域内秋冬栽培的6个主要花椰菜(Brassica oleraceaLinn.var.botrytis Linn.)资源的自交系育种材料的球高、球径、单球重、成熟期、毛花率和内叶盖球度等6个花球主要经济性状进行一般配合力(GCA)和特殊配合力(SCA)分析,并对花椰菜的各个性状进行了遗传相关性分析。结果表明:花椰菜的6个经济性状同时受加性和非加性效应控制。其中成熟期、毛花率、球高和内叶盖球度性状的一般配合力大于特殊配合力,受加性基因效应影响大;而球径、单球重等性状间一般配合力小于特殊配合力,在相当程度上受非加性基因控制。花椰菜各性状的狭义遗传力由大到小依次为:成熟期、毛花率、内叶盖球度、球高、球径和单球重。花椰菜的球高与单球重、球径与单球重、球高与成熟期、单球重与内叶盖球度、成熟期与内叶盖球度等5个成对性状应该同时选择;而球高与毛花率、球高与内叶盖球度、球径与成熟期、球径与毛花率、单球重与毛花率、成熟期与毛花率、毛花率与内叶盖球度等7个成对性状的选择可以独立进行,彼此间不会相互影响,可实现同一组合或品种具备多种优质性状。在6个自交系中,P2和P5是理想亲本;P4是配制耐寒组合的亲本材料;亲本P6应用价值最低。组合中表现最好的为P2×P4,各性状的特殊配合力均较优。 相似文献
968.
M.M. Vasanthakumari 《Archives Of Phytopathology And Plant Protection》2013,46(14):1641-1666
The fungal species from rhizosphere and rhizoplane of perennial grasses of the Western Ghats of India were studied for their pathogenicity, antagonism in vitro, substrate and root colonization abilities, rhizosphere competence, growth in different soil pH and inoculum shelf-life. Out of 138 non-pathogenic fungal isolates tested, 85 were antagonistic in vitro to chilli anthracnose pathogen Colletotrichum capsici. Fifteen isolates with >60% inhibition zone to pathogen culture had saprophytic and root and rhizosphere colonization abilities. The sorghum grain inocula of test antagonistic fungi- Fusarium oxysporum, Chaetomium globosum and Trichoderma harzianum had the shelf-life of 90 days at 20?±?2?°C and required optimum soil pH of 6.5. The above fungal isolates when tested for biocontrol of anthracnose disease in greenhouse and field caused reduction in seedling mortality and decreased disease incidence and severity at various plant growth stages and significant reduction in chilli fruit and seed infection. The test antagonistic fungi promoted seedling and mature plant growth and increased fruit and seed yield. Populations of these antagonistic fungi were fairly high in chilli rhizosphere at harvest. The present study indicated that antagonistic fungi from grass rhizosphere and rhizoplane could be used to control anthracnose and promote plant growth, and increase yield of chilli in field. 相似文献
969.
Nabil E. El-Wakeil Hamza Th. Farghaly Zakia A. Ragab 《Archives Of Phytopathology And Plant Protection》2013,46(8):705-714
Abstract The present work was conducted to evaluate the efficacy of Trichogramma evanescens (Westwood) in controlling the grape berry moth Lobesia botrana (Schiff) in two grape farms, in El-Beheira and El-Gharbia Governorates, northern Egypt during 2004 and 2005 seasons. T. evanescens was mass produced on Sitotroga cerealella (Olivier) eggs in the National Research Centre in Egypt. The horizontal and vertical searching activity of T. evanescens was studied to determine the proper way of distributing the Trichogramma cards in vineyards. Field experiments were also conducted to evaluate T. evanescens efficacy to control L. botrana on a large scale. Parasitism by T. evanescens on L. botrana eggs was greatly affected with the horizontal or vertical distance from the release points as well as with the rate of release. Parasitism reached over 97% and the percentage of reduction in damage caused by the pest reached 96.8% in treated plots. A significant increase in the crop was achieved in treated plots. T. evanescens could be a potential candidate for biological control of the grape moth in vineyards. 相似文献
970.
Y. Hou L. Cai X. Wang X. Chen D. Zhu D. Johnson X. Shi 《Journal of fish biology》2018,92(6):2022-2028
A series of stepped velocity tests were carried out in a Brett‐type swimming respirometer and the overall range in swimming performance for 12 Schizothoracinae species was measured. The relative critical swimming speed Ucrit and burst speed Uburst decreased with body length, while absolute Ucrit and Uburst increased with body length. Ucrit increased with temperature up to approximately 15° C and then decreased. Species with a high Ucrit also displayed a higher Uburst. 相似文献