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1.
The hypothesized sexual difference in the incidence of torus mandibularis in Eskimoid groups, as well as age and group differences, was studied in two Northwest Territories Eskimo groups and in an Aleut group (examined by Moorrees). The data were analyzed using statistical methods new to the field of anthropology. The method analyzes data sampled from a multinomial distribution. A hierarchy of log linear models are fitted to the cell counts of a contingency table. An iterative proportional fitting procedure is used to obtain expected cell counts under each log linear model. The “goodness of fit” of each model is tested by the log likelihood ratio. This statistic can be partitioned into additive components such that differences between models can be tested. In this way a “best” model, from the hierarchy of models, is chosen. Among these three groups of Eskimos, the incidence of torus mandibularis was not affected by sex but was affected by age and was different between the three groups. 相似文献
2.
The degree of aggregation of lettuce plants infected by aster yellows phytoplasma (AYP) was investigated in 12 fields from three experiments. Position of diseased and healthy plants was mapped in a 6–9×12-m section of each field; for most analyses, fields were divided into 10-plant quadrats. Mean disease incidence (p) ranged from 0.01 to 0.30. The frequency of diseased plants was described by the beta-binomial distribution, with an index of aggregation (θ) ranging from 0 to 0.17, positively correlated withp, and generally increasing over time within a field. Distance-class analysis revealed a core-cluster size of only a few plants. However, spatial autocorrelations ofp between quadrats were not significant, indicating that the scale of spatial pattern was small, generally less than 10 plants. An overall measure of aggregation was given by the slope parameter of the binary form of the power law, in which the log of the calculated variance is regressed on the log of the theoretical variance for a binomial distribution. The slope was 1.18 and significantly different from 1. Results for this “simple-interest” disease are interpreted in relation to the persistent transmission of AYP by its aster leafhopper vector. 相似文献
3.
Valley fever (coccidioidomycosis) is a disease caused by inhalation of spores from the soil-dwelling Coccidioides fungal species. The disease is endemic to semiarid areas in the western USA and parts of Central and South America. The region of interest for this study, Kern County, California, accounts for approximately 14% of the reported valley fever cases in the USA each year. It is hypothesized that the weather conditions that foster the growth and dispersal of the fungus influence the number of cases in the endemic area. This study uses regression-based analysis to model and assess the seasonal relationships between valley fever incidence and climatic variables including concurrent and lagged precipitation, temperature, Palmer Drought Severity Index, wind speed, and PM10 using data from 2000 to 2015. We find statistically significant links between disease incidence and climate conditions in Kern County, California. The best performing seasonal model explains up to 76% of the variability in fall valley fever incidence based on concurrent and antecedent climate conditions. Findings are consistent with previous studies, suggesting that antecedent precipitation is an important predictor of disease. The significant relationships found support the “grow and blow” hypothesis for climate-related coccidioidomycosis incidence risk that was originally developed for Arizona. 相似文献
4.
A key goal of aging research was to understand mechanisms underlying healthy aging and develop methods to promote the human healthspan. One approach is to identify gene regulations unique to healthy aging compared with aging in the general population (i.e., “common” aging). Here, we leveraged Genotype‐Tissue Expression (GTEx) project data to investigate “healthy” and “common” aging gene expression regulations at a tissue level in humans and their interconnection with diseases. Using GTEx donors' disease annotations, we defined a “healthy” aging cohort for each tissue. We then compared the age‐associated genes derived from this cohort with age‐associated genes from the “common” aging cohort which included all GTEx donors; we also compared the “healthy” and “common” aging gene expressions with various disease‐associated gene expressions to elucidate the relationships among “healthy,” “common” aging and disease. Our analyses showed that 1. GTEx “healthy” and “common” aging shared a large number of gene regulations; 2. Despite the substantial commonality, “healthy” and “common” aging genes also showed distinct function enrichment, and “common” aging genes had a higher enrichment for disease genes; 3. Disease‐associated gene regulations were overall different from aging gene regulations. However, for genes regulated by both, their regulation directions were largely consistent, implying some aging processes could increase the susceptibility to disease development; and 4. Possible protective mechanisms were associated with some “healthy” aging gene regulations. In summary, our work highlights several unique features of GTEx “healthy” aging program. This new knowledge could potentially be used to develop interventions to promote the human healthspan. 相似文献
5.
Prof. K. G. Janardan P. D. Dr. S. Pandarinath 《Biometrical journal. Biometrische Zeitschrift》1987,29(2):189-197
Biliary drainage and X-rays have been used singly and together in the diagnosis of gall bladder disease. Data from two sets of patients were statistically analyzed using log-linear analysis of contingency tables. The results of the study show that “biliary drainage” is dependent of “X-ray” and “Pathology”; abnormal X-ray is associated with abnormal pathology. Thus, biliary drainage is not of such value as to base surgery on it alone. However, X-rays are of significant value in the diagnosis of the gall bladder disease and to decide whether a surgery is needed or not. 相似文献
6.
A.B. Zarafi 《Archives Of Phytopathology And Plant Protection》2013,46(20):2458-2463
A survey was conducted from June 2012 to May 2013 in the Institute for Agricultural Research Jatropha plantation along Shika road to determine the progress of incidence and severity of Jatropha dieback caused by Fusarium sp. over a year. The disease incidence did not significantly differ among the months under review while disease severity was highest in August and lowest in March 2013. 相似文献
7.
J. P. Hanby 《American journal of physical anthropology》1980,52(4):565-575
Dyadic relationships are described for rhesus monkeys living in six groups. The kinds, frequencies, directionality, and overall patterning of interactions are examined over a twelve-month period for adult males, adult females, and young monkeys. Kinship, sex, age, reproductive conditions, time, events, and other social relations all affected dyadic relationship. Certain patterns of interactions characterized different relationships, such as those termed “special,” “tense,” “affiliative,” “conflicting.” A component approach is recommended for the understanding of relationships based on an appraisal of attraction, familiarity, and deference between individuals. The importance of assessing relationships in the group context is stressed. 相似文献
8.
Control and yield loss modelling of circular leaf spot of persimmon caused by Mycosphaerella nawae
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Symptoms of circular leaf spot of persimmon (CLSP), caused by Mycosphaerella nawae, consisted of necrotic spots on leaves, chlorosis and premature defoliation. Although CLSP is a foliar disease, early fruit maturation and abscission are frequently associated with the presence of lesions on leaves and defoliation, resulting in severe economic losses. Despite their importance for the design of efficient disease management programmes, quantitative relationships between CLSP incidence and yield loss are unknown. Therefore, fungicide efficacy trials were conducted during two consecutive years in Spain to induce different levels of disease severity, defoliation and yield loss. The effects of fungicide treatments on CLSP severity were analysed by ordinal logistic regression models. Relative yield loss values were regressed against the percentage of affected leaves or defoliated obtained at different evaluation dates. The disease had high negative impact and complete yield loss was observed in the absence of effective fungicide treatments. Preventive applications of pyraclostrobin, trifloxy‐strobin and mancozeb provided the best disease control and highest yields, up to 95.77 kg tree?1. An exponential relationship of CLSP incidence and defoliation with yield loss was found. In general, model fit and predictive ability was superior when defoliation, rather than incidence, was used as explanatory variable. The impact of defoliation on yield loss was higher in earliest evaluation dates, suggesting that early leaf abscission may be the main factor contributing to premature fruit drop and subsequent yield loss. Substantial yield losses were observed even with relatively low levels of CLSP incidence and defoliation. Therefore, it was not possible to define a critical action threshold for CLSP management based on foliar symptoms. 相似文献
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10.
全球气候变化对生态系统的影响是人类社会面临的紧迫而又严峻的挑战。气候变化带来的极端气候事件的增多, 直接影响到生态系统生产力和服务功能。本文总结了气候变化对植物-传粉昆虫互作的研究进展, 强调植物-传粉昆虫互作网络结构和其时空演变的解析, 以及互作关系和功能性状重组研究的重要性。近年来在气温持续上升背景下对植物-传粉昆虫互作关系影响的研究也受到了更多关注, 这些研究主要集中在两方面: 一是植物和传粉昆虫分布区的变化, 包括部分种群可能灭绝; 二是物候的变化, 即植物花期和传粉昆虫活动期的改变。植物与传粉昆虫任何一方在空间或时间上的改变, 都会导致传粉关系的错配或丢失。此外, 也可能导致植物-传粉昆虫双方的功能性状及其耦合的改变, 从而影响其互作关系的稳定。建议在今后的研究中关注: (1)覆盖生物多样性的多个尺度的研究; (2)对植物-传粉者互作网络的长期监测; (3)重要指示物种繁殖适合度评价; (4)植物-传粉昆虫互作双方功能性状在时间和空间尺度上的变化, 及其互作关系的重组; (5)关键植物和传粉昆虫类群的评估和保护。 相似文献
11.
《Saudi Journal of Biological Sciences》2017,24(7):1609-1613
ObjectivesThe aim of this study was to determine the association of “ABO” and “Rhesus” blood groups with incidence of breast cancer.MethodsIn this study, we identified 70 research documents from data based search engines including “PubMed”, “ISI-Web of Knowledge”, “Embase” and “Google Scholar”. The research papers were selected by using the primary key-terms including “ABO blood type”, “Rhesus” blood type and “breast cancer”. The research documents in which “ABO” and “Rhesus” blood types and breast cancer was debated were included. After screening, we reviewed 32 papers and finally we selected 25 research papers which met the inclusion criteria and remaining documents were excluded.ResultsBlood group “A” has high incidence of breast cancer (45.88%), blood group “O” has (31.69%); “B” (16.16%) and blood group “AB” has (6.27%) incidence of breast cancer. Blood group “A” has highest and blood group “AB” has least association with breast cancer. Furthermore, “Rhesus +ve” blood group has high incidence of breast cancer (88.31%) and “Rhesus –ve” blood group has least association with breast cancer (11.68%).ConclusionBlood group “A” and “Rhesus +ve” have high risk of breast cancer, while blood type “AB” and “Rhesus –ve” are at low peril of breast cancer. Physicians should carefully monitor the females with blood group “A” and “Rh +ve” as these females are more prone to develop breast cancer. To reduce breast cancer incidence and its burden, preventive and screening programs for breast cancer especially in young women are highly recommended. 相似文献
12.
A comparative study of dietary patterns (DPs) with breast cancer (BC) incidence in different countries has been performed. It was established that in the countries with a high incidence of BC (76 per 100 000 people) the levels of consumption of the “nutrients of animal foods,” “fruits and beverages,” and “alcoholic drinks” are 1.5–2 times higher and that of “cereals and vegetables” is 1.5 times lower than in the countries with a low incidence of BC (35 per 100 000). In Mediterranean countries, where incidence of BC is 51 per 100 000, the levels of consumption of “animal foods” is two times lower than the levels of consumption of “cereals and vegetables.” A method of assessing the impact of DPs on the incidence of BC has been proposed. 相似文献
13.
A 2‐year study on epidemic progress of apple scab was conducted at Randwijk, the Netherlands, in 1998 and 1999. The summer epidemic caused by conidia was studied instead of the well‐described spring season epidemic originating from ascospores. The aim was to investigate relationships between disease measurements, i.e. disease incidence and severity measures of apple scab, and their implications for the development of predictive models and threshold levels. The study characterized good relationships between the measurements on cultivar Jonagold using regression analyses in three disease control regimes (untreated, organic and integrated). For fruit quality prediction, the relationship between fruit incidence (If) and leaf incidence (Il) in the organic control regime was given by If = 1.966 + 0.402 × (Il) (R2 = 0.92). As a result of low level of disease in the integrated control regime, shoot incidence (Is), with higher values than leaf incidence, was better suited for prediction. The relationship was given by If = ?0.162 + 0.028 × (Is) (R2 = 0.91). For the integrated control regime, disease threshold levels were constructed for timing of the final fungicide application. If an apple grower wants to keep fruit infection under 1% incidence (harvest scab threshold), the timing of the final fungicide application (action threshold) should correspond to 4% shoot scab incidence at the beginning of August. The results are compared with similar studies and their biological interpretation is discussed. 相似文献
14.
K.G. Somashekhara Achar 《Archives Of Phytopathology And Plant Protection》2013,46(8):990-1004
Clitorea ternatea L. finds extensive application in therapeutic medicine. Forest regions of the Western Ghats, India were surveyed for foliar disease(s) caused in C. ternatea. The incidence and severity of foliar disease were determined during August 2006 to July 2009. The distribution of foliar disease incidence was determined by Taylor’s power law. The pathogen was tested for its seed-borne nature and seed transmission. Fungicides, like Bavistin, Antrocol, Hyzeb M-45 and Captra, were used for managing seed-borne pathogens in C. ternatea. Diseased foliages were tested for secondary metabolite content. Results indicated that the foliar disease in C. ternatea is caused by Colletotrichum dematium. The disease incidence and severity was moderately high. The disease is distributed homogeneously and heterogeneously in two forest regions. The pathogen is seedborne and transmitted from seed to plant. Among fungicides, Antrocol and Bavistin reduced seed mycoflora incidence. The disease caused increased production of alkaloid, flavonoid, phenol and sterol in foliages. 相似文献
15.
A.B. Zarafi 《Archives Of Phytopathology And Plant Protection》2013,46(8):952-961
A survey was conducted on Jatropha plantations within Zaria to assess disease incidence and severity on two fields along Shika road and near the dam (Irrigation site) of the Institute for Agricultural Research (IAR) at Samaru and a plantation of the National Research Institute for Chemical Technology (NARICT) at Basawa. An assessment of incidence and severity of the disease was done on six accessions collected from four Local Government Areas (Giwa, B/Gwari, Soba, Lere) of Kaduna state and grown in one of the I.A.R fields along Bomo road at Samaru. The accessions were collected from Gangara, Maidaro, Farin Gida (Giwa LGA), Birnin Gwari (B/Gwari LGA), Kayarda (Lere LGA) and Soba (Soba LGA). The causal organism of dieback on Jaropha curcas L, was isolated and its pathogenicity determined. The isolated Fusarium sp. incited dieback/stem-rot disease when inoculated on healthy Jatropha seedlings. The disease incidence was significantly higher on NARICT plantation compared to the two IAR fields which were not significantly different from each other. The accessions from Gangara, Kayarda, Birnin Gwari and Soba did not significantly differ from each other but had significantly higher disease incidence than those from Maidaro and Farin Gida. Accession from Soba had significantly higher disease severity compared to the accessions from all the other LGAs, which did not differ statistically from each other. 相似文献
16.
Variability within Clones of Potato cv. Russet Burbank to Infection and Severity of Common Scab Disease of Potato 总被引:1,自引:0,他引:1
C. R. Wilson 《Journal of Phytopathology》2001,149(10):625-628
Significant variability in the level of resistance to common scab disease (to both disease incidence – tuber surface area affected, and severity – lesion depth) within potato ( Solanum tuberosum ) cv. Russet Burbank clonal lines and other selected processing cultivars was shown. Across two trials, cvs. Russet Nugget and Shepody and Russet Burbank clone British Columbia were consistently grouped within the cluster of least disease incidence whereas cv. Russet Norkotah and Vancouver unit four were grouped within the cluster showing greatest disease incidence. Russet Nugget and British Columbia were also consistently grouped within the cluster showing least disease severity, whereas Shepody and Russet Burbank clone Starks were grouped within the cluster with greatest severity scores. For some clones, consistency of rating across trials was not always apparent. Of note for the Tasmanian industry, there were differences within the five commercial Vancouver clonal units used interchangeably, with unit 4 showing significantly greater disease severity and incidence than some of the other units. However the extent of increased disease never exceeded 1.75 times the best of the other Vancouver units and the relevance of these results to the relative field performance of unit 4 remains to be tested. 相似文献
17.
目的:探讨抑郁在帕金森病中(Parkinson’s disease,PD)的发生率及其影响因素。方法:对确诊的PD患者,采用汉密尔顿抑郁量表(Hamilt depression scale,HAMD)、简易精神状态检查量表(Mini-Mental State Examination,MMSE)及Webster功能评分量表进行评定,分析抑郁的发生情况和相关影响因素。结果:PD伴发抑郁者32例,抑郁的发生率为49.2%,病程、文化程度、Webster评分、MMSE评分与帕金森抑郁的发生均有统计学意义(P<0.05),年龄、性别、婚姻状况、经济情况与帕金森抑郁的发生均无统计学意义(P>0.05)。回归分析发现病程和病情严重程度是PD患者抑郁的危险因素。结论:PD患者有较高的抑郁发生率,抑郁的发生可能是社会心理、神经生物学多种因素作用的结果。 相似文献
18.
D. Socquet-Juglard B. Duffy J. F. Pothier D. Christen C. Gessler A. Patocchi 《Tree Genetics & Genomes》2013,9(2):409-421
Xanthomonas arboricola pv. pruni causes bacterial spot of stone fruit resulting in severe yield losses in apricot production systems. Present on all continents, the pathogen is regulated in Europe as a quarantine organism. Host resistance is an important component of integrated pest management; however, little work has been done describing resistance against X. arboricola pv. pruni. In this study, an apricot population derived from the cross “Harostar” × “Rouge de Mauves” was used to construct two parental genetic maps and to perform a quantitative trait locus analysis of resistance to X. arboricola pv. pruni. A population of 101 F1 individuals was inoculated twice for two consecutive years in a quarantine greenhouse with a mixture of bacterial strains, and disease incidence and resistance index data were collected. A major QTL for disease incidence and resistance index accounting respectively for 53 % (LOD score of 15.43) and 46 % (LOD score of 12.26) of the phenotypic variation was identified at the same position on linkage group 5 of “Rouge de Mauves.” Microsatellite marker UDAp-452 co-segregated with the resistance, and two flanking microsatellites, namely BPPCT037 and BPPCT038A, were identified. When dividing the population according to the alleles of UDAp-452, the subgroup with unfavorable allele had a disease incidence of 32.6 % whereas the group with favorable allele had a disease incidence of 21 %, leading to a reduction of 35.6 % in disease incidence. This study is a first step towards the marker-assisted breeding of new apricot varieties with an increased tolerance to X. arboricola pv. pruni. 相似文献
19.
Andrew V.Z. Brower 《Cladistics : the international journal of the Willi Hennig Society》2016,32(5):573-576
The origins and meanings of “cladogram” are reviewed. Traditionally, “cladogram” has been defined as a graphical representation of an empirical hypothesis of relationships among taxa, based on evidence from synapomorphies alone. Disturbingly, numerous recent authors treat “cladogram” as synonymous with “dendrogram” and do not appreciate the particular methodological connotations of the former term. This is lamented. 相似文献
20.
Nonalcoholic fatty liver disease(NAFLD) is the most common liver disease in the world today.Its incidence in adults and children is rising rapidly due to the ongoing epidemics of obesity and type 2 diabetes.Hence,it has become a global public health issue.Environmental factors have been found to play a major role in the etiology of NAFLD,especially for genetically susceptible populations. Among these,one of the most important factors is junk food,especially the typical "Western-style" diet rich in simple carbohydrates, saturated fat,and highly processed food materials.Genetic predisposition to NAFLD does occur;however,a precise definition of genetic factors responsible for NAFLD is still lacking.Specific variants of different genes have been shown to present a risk for NAFLD.Genetic studies might be helpful in the management of the disease by developing novel treatment strategies based on individual’s genotype. 相似文献