Associations and distribution of benthic nematodes in the Ethiopian Rift Valley lakes

The nematode associations in six Ethiopian rift lakes, one man-made lake, and three crater lakes were studied and related to water conductivity, lake depth and sediment particle size. The lakes investigated lie at moderate altitudes (1200–2000 m), are alkaline and vary in their conductivities. The rift lakes Abijata and Shala and the crater lakes Aranguadi, Kilotes and Chitu are soda lakes (K₂₅ > 6000 μS cm⁻¹), while the remaining five lakes and the man-made Lake Koka are within the freshwater range of conductivity (K₂₅ < 6000 μS cm⁻¹). A total of 16 species were identified including six new species. The nematode associations varied between lakes and were restricted to very few species in each lake. Most nematodes were restricted to non-saline lakes. The most dilute L. Zwai had a higher number of nematode species (12) and abundance than other lakes. The saline lakes Shala and Kilotes had nematode assemblages made up of only a single species (Mesodorylaimus macrospiculum). No nematodes were found in the hypersaline crater L. Chitu. Tobrilus africanus appeared more euryhaline than other nematodes occurring at conductivities as high as 15 000 μ S cm⁻¹ (L. Abijata). Five of the most common species (Dorylaimus sp., Monhystera stagnalis, Aphanolaimus tudoranceai, Tobrilus africanus and Actinolaimus perplexus) were associated with medium grained sand. A monthly variation in density of nematodes in L. Zwai is also shown.     

Seasonality and abundance of some dominant crustacean zooplankton in Lake Awasa,a tropical rift valley lake in Ethiopia

The zooplankton of a Rift Valley lake in Ethiopia, Awasa, was sampled at 3 stations for 2 years (1986 and 1987) concurrently with various meteorological and limnological measurements. The spatial and temporal variation in abundance of some numerically dominant crustaceans, Mesocyclops aequatorialis similis (Copepoda), Thermocyclops consimilis (Copepoda) and Diaphanosoma excisum (Cladocera) is discussed. Temporal (months, sampling dates) rather than spatial (station) variability accounts for more than 50% of the total variance in zooplankton abundance but horizontal patchiness exists during periods of high zooplankton density. Sampling errors were generally low, except for counts of cyclopoid nauplii (subsampling) and Diaphanosoma (inter-replicate variance). Zooplankton showed distinct seasonality associated with the mixing cycle of the lake. Total numbers increased to more than 200 000 m⁻³ during the unstratified period (July to September). Low numbers were evident during stratification (February to May) when zooplankton numbers did not exceed 15 000 m⁻³. Individual zooplankton species and age classes showed variable seasonal amplitudes, ranging from 6.4 (nauplius 3) to 44.8 (copepodite 3 of Mesocyclops). We discuss some possible causes for zooplankton seasonality in Lake Awasa, and also review zooplankton seasonal cycles in other tropical lakes, especially African ones.     

Allozyme diversity in pheasants (<Emphasis Type="Italic">Phasianus</Emphasis> spp.) from breeding stations in Serbia

The pheasant breeds are widely used for restocking of natural populations depleted by hunting. The pheasant population number decline was detected during the 1970s in many hunting areas of Europe. One of its possible reasons might be the loss of adaptability in populations originating from breeding stations, which was caused by inbreeding depression. The aim of this paper was the analysis of genetic variability in pheasant populations from three breeding stations in Vojvodina province (Serbia) by means of allozyme diversity detection. The allozyme variability analysis of pheasants from all three breeding stations revealed polymorphisms at nine loci: Ldh-1, Mor-1, Mor-2, Es-1, Mod-2, Pgd, Gpi-2, Odh, and Sod. The analysis of individuals from three different breeding stations showed mean values of observed heterozygosity of H _o=0.137, polymorphism P _95%=30%, and H/P ratio H/P=0.430, which indicate a normal level of genetic variability for bird populations. Comparative analysis of three pheasant populations showed a high level of interpopulation differentiation.     

WHBE兔血液蛋白的特性

目的比较大耳白黑眼兔（WHBE兔）与日本大耳白兔（JW兔）和新西澜兔（NZW兔）血液蛋白的多态性,从分子水平了解WHBE兔特殊性状的遗传背景。方法采用聚丙烯酰胺凝胶电泳对WHBE兔、JW兔和NZW兔血液中的前白蛋白（Pr）,后白蛋白（Po）,前转铁蛋白1（Prt1）,前转铁蛋白2（Prt2）,转铁蛋白1（Tf1）,转铁蛋白2（Tf2）,后转铁蛋白（Ptf）,慢α球蛋白（Sag）、血红蛋白（Hbα、Hbβ）和白蛋白（Alb）共11个蛋白位点进行检测。结果Pr、Ptf、Hbα、Hbβ、Alb、Po、Sag和Prt2在所有实验兔个体中的表型一致,而Tf1、Tf2和Prt1的表型在各实验兔品系间存在显著差异。在Tf1位点,NZW兔以BC表型为主,无AA型;JW兔只有AA型,而WHBE兔以AB型为主。在Tf2位点,NZW兔有AA型,而JW兔和WHBE兔无AA型。在Prt1位点,NZW兔无AB、BB和BC表型而有AC表型。NZW兔蛋白位点的平均杂合度大于JW兔和WHBE兔。JW兔与WHBE兔的遗传距离最近。结论Tf1、Tf2和Prt1可作为区分NZW兔、JW兔和WHBE兔的特征标记,并且与WHBE兔特殊性状形成有关。JW兔与WHBE兔的亲缘关系最近。     

Deciphering genetic diversity analysis of saffron (Crocus sativus L.) using RAPD and ISSR markers

The existence of genetic diversity in Crocus sativus has globally remained a mystery till date. The study investigated PCR based DNA amplification profile of saffron using ISSR and RAPD based primers. A total of 38 amplicons were generated by ISSR primers in the range from 7 to 12 with an average of 9.50 bands per primer. 20 bands were found to be polymorphic and 18 were monomorphic with an average percentage of polymorphism as 52.48%. RAPD based amplification revealed a total 161 amplicons, 107 as polymorphic and 54 as monomorphic with an average percentage of polymorphism as 66.44%. Cumulative results of RAPD and ISSR demonstrated that Nei-Li’s similarity index ranged between 0.70 and 0.97. The results of AMOVA has revealed 9% of variance among populations and 91% of variance within populations, Φ PT was found as 0.089, which indicates existence of genetic differences though limited. In conclusion, the results indicate that saffron accessions are minimally genetically differentiated, which could be capitalized in future breeding programmes to ameliorate this precious crop.     

晋西南旧石器考古学研究现状及其展望

晋西南古称河东,位于汾渭地堑中部,包括临汾盆地、运城盆地以及中条山南麓黄河沿岸。这里自古就是中华民族文明重要发祥地,也是研究人类起源、发展、演化的重要地区。20世纪50年代以来,考古工作者在山西地堑发现了300余处旧石器时代遗址和地点。这些发现业已证明晋西南的临汾、运城以及中条山南麓黄河沿岸,从早更新世初期直到更新世结束一直有人类在这片土地上繁衍生息。其中西侯度遗址、匼河遗址群、丁村遗址群、下川遗址群、柿子滩遗址群,代表了东亚旧石器时代人类200万年以来从能人→直立人→早期智人→晚期智人各个不同发展阶段一个完整的演化历程。因此,这里成为中国大陆一个非常重要的远古人类演化场。本文试图通过对这一区域旧石器考古的回顾,找出我们工作中的不足以及需要努力的方向,并向本地区考古学研究的开拓者贾兰坡、王建、王择义等老一辈考古学家致敬。     

三个品种豚鼠血液蛋白多态性的比较分析

目的比较分析白毛黑眼（WHBE）豚鼠和DHP豚鼠、花色豚鼠三个品种豚鼠在13个血液蛋白位点上的多态性。方法采用垂直板浓度和pH均不连续的聚丙烯酰胺凝胶电泳法对WHBE豚鼠、DHP豚鼠和花色豚鼠的66只个体的后白蛋白（Po）、前转铁蛋白1（Prt1）、前转铁蛋白2（Prt2）、转铁蛋白1（Tf1）、转铁蛋白2（Tf2）、后转铁蛋白（Ptf）、慢α球蛋白（Sag）、红细胞酯酶（Es）、血清酯酶1（Est1）、血清酯酶3（Est3）、血红蛋白α（Hbα）、血红蛋白β（Hbβ）和白蛋白（Alb）共13个蛋白位点进行了电泳及染色,再利用电泳图谱对各蛋白位点基因频率、平均杂合度和遗传距离进行计算,然后结合聚类分析。结果 Tf1、Tf2、Ptf、Est1和Es在三个豚鼠品种中表现为多态,其中Tf1可作为识别WHBE豚鼠的遗传标记。Po、Prt1、Prt2、Sag、Est3、Hbα、Hbβ和Alb等位点在三个豚鼠品种中的表型一致。Hardy-Weinberg平衡状态分析表明,Es为DHP豚鼠的高度不平衡位点。Ptf为花色豚鼠的高度不平衡位点。在WHBE豚鼠中,Tf1为高度不平衡位点,Est1为不平衡位点。在三个豚鼠品种中,所检测的13个蛋白位点的平均杂合度的排列顺序为：花色豚鼠（0.350 1）〉WHBE豚鼠（0.339 0）〉DHP豚鼠（0.313 5）。聚类分析结果表明,花色豚鼠和WHBE豚鼠的遗传遗传距离最近（0.064 3）,DHP豚鼠与花色豚鼠的遗传距离最远（0.179 2）。结论利用这些蛋白位点可以有效鉴别WHBE豚鼠、DHP豚鼠和花色豚鼠血液蛋白的遗传多态性。     

Blood protein variation in a population of ethiopian vervet monkeys (Cercopithecus aethiops aethiops)

Seven small groups of vervet monkeys (Cercopithecus aethiops aethiops), totaling 124 individuals, from Awash National Park, Ethiopia, were trapped and blood samples were obtained. Twenty-three loci were examined by starch gel electrophoresis and four loci, Tf, E, ADA, and PMG2 were found to be polymorphic. The average heterozygosity (H?) of the population was calculated to be 5.6%. No significant deviations from Hardy-Weinberg equilibrium proportions occurred and a chi-square test for group homogeneity was also not significant. Average F_ST for all polymorphic loci was calculated to be 0.062. This suggests that the entire group functions as a single Mendelian population.     

Electromyography of pongid shoulder muscles II. Deltoid, rhomboid and "rotator cuff"

Red cell antigen, serum protein and red cell enzyme groups were determined for a series of 1,821 individuals belonging to six language families in Western New Guinea. Three of the language families represent groupings of languages spoken by people in the swampy coastal plain of south central Western New Guinea, two belong to the Central Highlands and one to the Lake Plain area near the confluence of the Idenburg and Rouffaer Rivers. The distribution of genetic markers reveals similarities with other parts of New Guinea. The A₂ allele is absent in the ABO system, the frequency of Ns in the MNS system is very high as is the R₁ (CDe) allele in the Rh system. Hp¹ frequencies are high, and the transferrin allele Tf^D 1 is present as in other parts of New Guinea. In the red cell enzyme systems several alleles were detected which are characteristic of Papuan, and in some cases other Melanesian populations: these include MDH³, PGK⁴, PGK², PGM⁹₂, PGM¹⁰₂, as well as some very restricted alleles such as Peptidase B⁶ and Pep B². Three indices of genetic distance were computed. The most striking results are the genetic closeness of the Dani and Moni populations from the Central Highlands to the Asmat on the southern coastal plain, and the relative remoteness of the Awyu from the other south coastal populations. The results are discussed in terms of recent theories on the origin and dispersal of Papuan languages.     

山东省地方绵羊品种微卫星遗传多态性

利用24个微卫星标记,分析了山东省内原有地方绵羊品种的遗传多样性.结果表明,在来自4个品种共71个种群的164只绵羊中,共检测到等位基因467个,有效等位基因占49.59％,不同微卫星基因座之间的等位基因数差异大于品种之间的差异;发现特有等位基因123个,优势等位基因43个.在所有微卫星基因座中,89％处于Hardy-Weinberg不平衡状态,有50％属于中性基因座.不同品种的微卫星基因座多态信息含量呈高度多态（PIC＞0.5）,Shannon指数较高（I＞1.5）,平均观察杂合度（范围0.454～0.560）明显低于期望杂合度（范围0.831～0.849）,证明4个地方绵羊种群具有丰富的遗传多样性和广泛的遗传基础,但品种内存在着一定程度的近交.聚类分析表明,山东地方绵羊品种遗传进化关系明确,可划分为鲁西地区的小尾寒羊和大尾寒羊、鲁东地区的山地绵羊和洼地绵羊两大类群,其遗传距离与地理分布距离相一致.     

A collation of marker gene and dermatoglyphic diversity at various levels of population differentiation

The use of dermatoglyphic traits to describe interpopulational diversity among human populations at various levels of differentiation is compared with similar analysis of gene frequency data by means of nonparametric methods employing distance matrices and dendrograms, and by a partition of total variability into its between and within population components. Congruence of dermatoglyphics and gene markers appears to vary with level of population differentiation — the association remains insignificant until racial level of differentiation is considered. Different pitfalls of the data used are mentioned. The interpretation of these findings is discussed by comparison with other non-human studies.     

裂谷热病毒囊膜蛋白基因DNA免疫的研究

分别将裂谷热病毒(Rift Valley Fever Virus,RVFV)囊膜糖蛋白GN、GC和G(N C)基因亚克隆至真核表达载体pCAGGS多克隆位点鸡β-actin转录启动子下游,分别构成pCAGG-RVFV-GN、pCAGG-RVFV-GC和pCAGG-RVFV-G(N C)。免疫沉淀试验结果表明,重组RVFV蛋白GN、GC分别在pCAGG-RVFV-GN、pCAGG-RVFV-G(N C)转染HeLa细胞中获得表达,并具有良好免疫反应性。pCAGG-RVFV-GN、pCAGG-RVFV-GC和pCAGG-RVFV-G(N C)质粒DNA混合物按100μg/只剂量肌肉注射免疫6周龄BALB/c小鼠。每隔4周用相同的剂量加强免疫,第二次加强免疫3周后采血、分离血清备用。分别以杆状病毒表达RVFV囊膜蛋白GN、GC制备的抗原液包被ELISA板,间接ELISA检测DNA免疫鼠血清中RVFV囊膜蛋白G(N C)特异性抗体,具有良好的敏感性和特异性。另外,DNA免疫鼠血清中的特异抗体可有效中和RVFV囊膜蛋白G(N C)介导的伪型VSV重组病毒侵入RVFV易感宿主细胞的感染性。结果表明,pCAGG-RVFV-GN、pCAGG-RVFV-GC和pCAGG-RVFV-G(N C)质粒DNA混合物作为DNA疫苗具有防制裂谷热的潜力。     

The analysis of hidden electrophoretic variation: Interspecific electrophoretic differentiation and amino acid divergence

Summary In a study of 25 human variants and 23 evolutionary alleles of hemoglobin we show that intraspecific and interspecific patterns of electrophoretic variability are not comparable. Significant deviation from the predicted electrophoretic differentiation between evolutionary alleles is normally found only when amino acid sequence divergence exceeds 10%. When two sequences had diverged at less than 30 out of 287 amino acid residues sites, only 7% of comparisons showed significant deviations from the expected difference of electrophoretic mobility, while significant deviation was shown by 57% of comparisons involving 30–40 residue differences, by 79% in the case of 51–60 differences and by all of the comparisons involving more than 60 differences. In contrast, human variants, which differ by only one or two amino acid residues (less than 1% difference), had significant deviations in 58% of comparisons. Those mutations that appear as fixed differences in the evolutionary material probably represent only a subset of the mutations which can appear within the species. The results suggest that statistical comparisons such as genetic distance may not measure the same process within a species as between species. This is due not to inherent problems with the statistic, but rather to inherent differences in the nature of molecular changes that are detectable by electrophoresis at different stages of population divergence.     

The Ethiopian Rift Valley lakes: chemical characteristics of a salinity-alkalinity series

The study on 10 lakes within the Ethiopian Rift Valley during March–May 1991 covered a range of conductivity (K₂₅) between 286 and 49100 µS cm^–1. HCO₃ ^– — CO _inf3 ^sup2– and Na⁺ were the dominant ions in all the lakes. Concentrations of K⁺, Cl^– and SO _inf4 ^sup2– increased with increasing salinity and alkalinity, whereas Ca²⁺ and Mg²⁺ decreased. Comparison of these data with previous records showed that a ten-fold dilution of total ionic concentration occurred over 30 years in Lake Metahara and about three-fold increase occurred over 65 years in Lake Abijata. Concentrations of soluble silica were generally high (12–222 mg SiO₂ 1^–1) and increased with increasing salinity, except for Lake Chamo which showed SiO₂ depletion (to < 1 mg SiO₂ 1 ^–1) over the past three decades.The relationship between ionic concentration and phosphorus was irregular although high phosphorus concentrations generally corresponded with increasing salinity. Fitting data to the Dillon & Rigler (1974) chlorophyll a — total phosphorus relationship suggested that lakes Zwai, Awassa and Chamo are phosphorus-limited, whereas others have surplus phosphorus.     

New studies of post-Pleistocene human skeletal remains from the Rift Valley,Kenya

Prehistoric human crania from Bromhead's Site, Willey's Kopje, Makalia Burial Site, Nakuru, and other localities in the Eastern Rift Valley of Kenya are reassessed using measurements and a multivariate statistical approach. Materials available for comparison include series of Bushman and Hottentot crania, South and East African Negroes, and Egyptians. Up to 34 cranial measurements taken on these series are utilized to construct three multiple discriminant frameworks, each of which can assign modern individuals to a correct group with considerable accuracy. When the prehistoric crania are classified with the help of these discriminants, results indicate that several of the skulls are best grouped with modern Negroes. This is especially clear in the case of individuals from Bromhead's Site, Willey's Kopje, and Nakuru, and the evidence hardly suggests post-Pleistocene domination of the Rift and surrounding territory by “Mediterranean” Caucasoids, as has been claimed. Recent linguistic and archaeological findings are also reviewed, and these seem to support application of the term Nilotic Negro to the early Rift populations.