全医嘱静脉药物配置中心配送时效的优化

目的 运用现代物流管理方法,对运输人员进行工作量分析和运送人力分析,以满足静脉药物配置中心长期医嘱和临时医嘱的药品配送需求。方法 根据自身硬件和软件条件,利用统计学方法对运输工作量和运输人员的人力等方面进行分析,再利用现代物流管理理念和方法对药品配送中的硬件准备和路径选择拟定PIVAS所配药品的运送需求。结果 从硬件准备到路径选择,同时结合统计学计算运输工作量和运输人员的人力分析,从实际出发使医院内部物流能满足PIVAS所配药品的运送需求。结论 PIVAS配置长期医嘱,同时也能承接临时医嘱的配置,完善的物流配送是保证其正常动作的基础。     

Gene flow and genetic microdifferentiation of a transplanted Tlaxcaltecan Indian population: Saltillo

This study is one portion of a research program on: (1) the genetic effects of transplantation of Mexican Indian populations into diverse environments; (2) the effect of Spanish colonization on the genetics of Mexico. In 1591, 91 Tlaxcaltecan families were transplanted into northern Mexico to aid in the pacification of the Chichimec Indians. The descendants of these migrants are the residents of the City of Saltillo in the state of Coahuila. Since Saltillo had undergone considerable growth due to industrialization, two adjoining barrios–Chamizal and La Minita–were chosen for this study. Chamizal is an old established barrio where the descendants of the Tlaxcaltecan colonialists resided, while La Minita is a small shantytown made up of squatters from the surrounding areas. Blood specimens were collected by venipuncture from 302 participants and analyzed for 16 blood groups, 13 serum protein and red blood cell enzyme systems. The gene frequency distribution suggests that the Saltillo populations are a triracial hybrid made up of Indian, African and Spanish parental con-tributions. Admixture estimates and genetic distance measures are both in agreement with the ethnohistory of the transplanted Tlaxcaltecan community.     

MORPHOLOGICAL AND MOLECULAR EVIDENCE REVEALS RECENT HYBRIDIZATION BETWEEN GORILLA TAXA

Molecular studies have demonstrated a deep lineage split between the two gorilla species, as well as divisions within these taxa; estimates place this divergence in the mid-Pleistocene, with gene flow continuing until approximately 80,000 years ago. Here, we present analyses of skeletal data indicating the presence of substantial recent gene flow among gorillas at all taxonomic levels: between populations, subspecies, and species. Complementary analyses of DNA sequence variation suggest that low-level migration occurred primarily in a westerly-to-easterly direction. In western gorillas, the locations of hybrid phenotypes map closely to expectations based on population refugia and riverine barrier hypotheses, supporting the presence of significant vicariance-driven structuring and occasional admixture within this taxon. In eastern lowland gorillas, the high frequency of hybrid phenotypes is surprising, suggesting that this region represents a zone of introgression between eastern gorillas and migrants from the west, and underscoring the conservation priority of this critically endangered group. These results highlight the complex nature of evolutionary divergence in this genus, indicate that historical gene flow has played a major role in structuring gorilla diversity, and demonstrate that our understanding of the evolutionary processes responsible for shaping biodiversity can benefit immensely from consideration of morphological and molecular data in conjunction.     

The Griqua of Campbell, Cape Provice, South Africa.

The Griqua of Campbell in the Cape Province of South Africa are reputed to be descended from an amalgam of Khoi ("Hottentots") with various Caucasoid, Negroid and East Asian elements at the Cape of Good Hope. A stormy history of migration and deprivation has left this small residuum on the edge of the Kalahari Desert. It was hoped that a sero-genetic study of these people, who proudly preserve their identity, might provide further insights into the genetic consitution of their Khoi forebears. Despite the retention of the language of their own, an social mores distinct from of other Mixed populations, they have been shown, however, to have received an appreciable inflow of non-Khoisan genes. This has probably resulted from social factors such as the prestige attaching to Griqua membership and the willingness of the Griqua to assimilate outsiders, combined with the tendency of Campbell Griqua to migrate elsewhere. There are no significant differences between "Griqua" members of the population and those who are not recognized as "Griqua."     

The St. Lawrence Island Eskimos: genetic variation and genetic distance

The Eskimos of St. Lawrence Island have been typed for genetic variation at 44 discrete genetic loci. Three private polymorphisms, at the 2,3-diphosphoglycerate mutase, peptidase B, and purine nucleoside phosphorylase loci, have been observed, which may be useful in future studies of genetic relationships between Eskimos and other circumpolar populations. Genetic distance analysis reveals a close relationship between the St. Lawrence Island Eskimos and other Eskimo populations and that the Eskimo populations form a distinct cluster from Amerindian populations. The St. Lawrence Island Eskimos appear to be more similar to Asiatic Eskimos than to other groups. Caucasian admixture in this population is estimated to be between 2 and 7%.     

Historical introgression among the American live oaks and the comparative nature of tests for introgression

Introgressive hybridization challenges the concepts we use to define species and infer phylogenetic relationships. Methods for inferring historical introgression from the genomes of extant species, such as ABBA‐BABA tests, are widely used, however, their results can be easily misinterpreted. Because these tests are inherently comparative, they are sensitive to the effects of missing data (unsampled species) and nonindependence (hierarchical relationships among species). We demonstrate this using genomic RADseq data sampled from all extant species in the American live oaks (Quercus series Virentes), a group notorious for hybridization. By considering all species and their phylogenetic relationships, we were able to distinguish true hybridizing lineages from those that falsely appear admixed. Six of seven species show evidence of admixture, often with multiple other species, but which is explained by introgression among a few related lineages occurring in close proximity. We identify the Cuban oak as the most admixed lineage and test alternative scenarios for its origin. The live oaks form a continuous ring‐like distribution around the Gulf of Mexico, connected in Cuba, across which they could effectively exchange alleles. However, introgression appears highly localized, suggesting that oak species boundaries and their geographic ranges have remained relatively stable over evolutionary time.     

Spatially explicit Bayesian clustering models in population genetics

This article reviews recent developments in Bayesian algorithms that explicitly include geographical information in the inference of population structure. Current models substantially differ in their prior distributions and background assumptions, falling into two broad categories: models with or without admixture. To aid users of this new generation of spatially explicit programs, we clarify the assumptions underlying the models, and we test these models in situations where their assumptions are not met. We show that models without admixture are not robust to the inclusion of admixed individuals in the sample, thus providing an incorrect assessment of population genetic structure in many cases. In contrast, admixture models are robust to an absence of admixture in the sample. We also give statistical and conceptual reasons why data should be explored using spatially explicit models that include admixture.     

A genomewide admixture mapping study for yield factors and morphological traits in a cultivated cocoa (Theobroma cacao L.) population

The selection of productive varieties of modern Criollo cocoa, showing fine aromatic qualities in their beans, is of major interest for some producing countries, such as Venezuela. Cultivated populations of Modern Criollo or Trinitario varieties may be suitable for admixture mapping analysis, as large blocks of alleles derived from two identified divergent ancestors, recently admixed, are still preserved, after a few generations of recombination, similar to experimental mapping progenies. Two hundred and fifty-seven individuals from a cultivated population of Modern Criollo were selected and analysed with 92 microsatellite markers distributed along the genome. This population exhibited a wide range of variability for yield factors and morphological features. Population structure analysis identified two main subgroups corresponding to the admixture from the two ancestors Criollo and Forastero. Several significant associations between markers and phenotypic data (yield factors and morphological traits) were identified by a least squares general linear model (GLM) taking into account the population structure and the percentage of admixture of each individual. Results were compared with classical QTL analyses previously reported for other cacao populations. Most markers associated to quantitative traits were very close to QTLs detected formerly for the same traits. Associations were also identified between markers and several qualitative traits including the red pigmentation observed in different organs, mainly associated to common markers in linkage group 4.     

Alternative forms for genomic clines

Understanding factors regulating hybrid fitness and gene exchange is a major research challenge for evolutionary biology. Genomic cline analysis has been used to evaluate alternative patterns of introgression, but only two models have been used widely and the approach has generally lacked a hypothesis testing framework for distinguishing effects of selection and drift. I propose two alternative cline models, implement multivariate outlier detection to identify markers associated with hybrid fitness, and simulate hybrid zone dynamics to evaluate the signatures of different modes of selection. Analysis of simulated data shows that previous approaches are prone to false positives (multinomial regression) or relatively insensitive to outlier loci affected by selection (Barton's concordance). The new, theory‐based logit‐logistic cline model is generally best at detecting loci affecting hybrid fitness. Although some generalizations can be made about different modes of selection, there is no one‐to‐one correspondence between pattern and process. These new methods will enhance our ability to extract important information about the genetics of reproductive isolation and hybrid fitness. However, much remains to be done to relate statistical patterns to particular evolutionary processes. The methods described here are implemented in a freely available package “HIest” for the R statistical software (CRAN; http://cran.r-project.org/ ).     

The breakdown of genomic ancestry blocks in hybrid lineages given a finite number of recombination sites

When a lineage originates from hybridization genomic blocks of contiguous ancestry from different ancestors are fragmented through genetic recombination. The resulting blocks are delineated by so called junctions, which accumulate with every generation that passes. Modeling the accumulation of ancestry block junctions can elucidate processes and timeframes of genomic admixture. Previous models have not addressed ancestry block dynamics for chromosomes that consist of a finite number of recombination sites. However, genomic data typically consist of informative markers that are interspersed with fragments for which no ancestry information is available. Hence, repeated recombination events may occur between markers, effectively removing existing junctions. Here, we present an analytical treatment of the dynamics of the mean number of junctions over time, taking into account the number of recombination sites per chromosome, population size, genetic map length, and the frequency of the ancestral species in the founding hybrid swarm. We describe the expected number of junctions using equidistant molecular markers and estimate the number of junctions using random markers. This extended theory of junctions thus reflects properties of empirical data and can serve to study the genomic patterns following admixture.