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1.
It has been suggested by some that the acquisition of symbolic capital in terms of honor, prestige, and power translates into an accumulation of material capital in terms of tangible belongings, and that on the basis of these goods high reproductive success may be achieved. However, data on completed fertility rates over more than one generation in so-called traditional societies have been rare. Ethnographic and demographic data presented here on the pastoral Bakkarwal of northern India largely corroborate the hypothesis concerning the interdependence between the attainment of various cultural goals and differential reproduction rates and indicate that the numbers of (especially male) surviving offspring and siblings are crucial to a man’s position in society.  相似文献   
2.
Summary Mucor miehei (IM 20) and Candida antarctica (SP 382) lipases were used for esterification of free fatty acids in the absence of organic solvent or transesterification of fatty acid methyl esters in hexane with isopropylidene glycerols. Acid catalyzed cleavage of the isopropylidene groups resulted in the formation of monoacyl glycerol (MAG) and diacyl glycerol (DAG). Both oleic (18:1 n-9) and eicosapentaenoic acid, EPA (20:5 n-3) were successfully incorporated into glycerides. Total acyl donor conversion ranged from 46.9 – 96.9% with MAG content of up to 88.5%.  相似文献   
3.
A new natural imino-alcohol, 2,5-dihydroxymethyl 3,4-dihydroxypyrrolidine has been isolated from the leaves of Derris elliptica. Its structure was determined by chemical and physical methods.  相似文献   
4.
An eastern gorilla group of the Mt. Kahuzi region (République du Za?re) was studied over 15 months. Its migration route was determined, and the various biotopes it visited are described. A record was made of its main food plants, and of the plant parts eaten. For nine important food plants the protein content, the concentration of the individual amino acids and the water content were measured for the plant parts eaten and for those not eaten. For some of these plant parts the Na, K, Ca and Mg content were also determined. No general correlation between food selection and one or several of these factors could be found. The development and value of a traditionally determined mixed diet is discussed.  相似文献   
5.
We present a method for automatically extracting groups of orthologous genes from a large set of genomes by a new clustering algorithm on a weighted multipartite graph. The method assigns a score to an arbitrary subset of genes from multiple genomes to assess the orthologous relationships between genes in the subset. This score is computed using sequence similarities between the member genes and the phylogenetic relationship between the corresponding genomes. An ortholog cluster is found as the subset with the highest score, so ortholog clustering is formulated as a combinatorial optimization problem. The algorithm for finding an ortholog cluster runs in time O(|E| + |V| log |V|), where V and E are the sets of vertices and edges, respectively, in the graph. However, if we discretize the similarity scores into a constant number of bins, the runtime improves to O(|E| + |V|). The proposed method was applied to seven complete eukaryote genomes on which the manually curated database of eukaryotic ortholog clusters, KOG, is constructed. A comparison of our results with the manually curated ortholog clusters shows that our clusters are well correlated with the existing clusters  相似文献   
6.
2-Keto-3-deoxy-6-phosphogluconate (KDPG) aldolase is a key enzyme in the Entner-Doudoroff pathway of bacteria. It catalyzes the reversible production of KDPG from pyruvate and D-glyceraldehyde 3-phosphate through a class I Schiff base mechanism. On the basis of aldolase mechanistic pathway, various pyruvate analogues bearing beta-diketo structures were designed and synthesized as potential inhibitors. Their capacity to inhibit aldolase catalyzed reaction by forming stabilized iminium ion or conjugated enamine were investigated by enzymatic kinetics and UV-vis difference spectroscopy. Depending of the substituent R (methyl or aromatic ring), a competitive or a slow-binding inhibition takes place. These results were examined on the basis of the three-dimensional structure of the enzyme.  相似文献   
7.
8.
A predictive model for Pichia pastoris expression of highly active recombinant Candida rugosa LIP1 was developed by combining the Gompertz function and response surface methodology (RSM) to evaluate the effect of yeast extract concentration, glucose concentration, temperature, and pH on specific responses. Each of the responses (maximum population densities, specific growth rate (mumax), protein concentration, and minimum lag phase duration) was determined using the modified Gompertz function. RSM and 4-factor-5-level central composite rotatable design (CCRD) were adopted to evaluate the effects of growth parameters, such as temperature (21.6-38.4 degrees C), glucose concentration (0.3-3.7%), yeast extract (0.16-1.84%), and pH (5.3-8.7) on the responses of P. pastoris growth kinetics.Based on ridge maximum analysis, the optimum population density conditions were: temperature 24.4 degrees C, glucose concentration 2.0%, yeast extract 1.5%, and pH 7.6. The optimum specific growth rate conditions were: temperature 28.9 degrees C, glucose concentration 2.0%, yeast extract 1.1%, and pH 6.9. The optimum protein concentration conditions were: temperature 24.2 degrees C, glucose concentration 1.9%, yeast extract 1.5%, and pH 7.6. Based on ridge minimum analysis, the minimal lag phase conditions were: temperature 32.3 degrees C, glucose concentration 2.1%, yeast extract 1.1%, and pH 5.4. For the predicted value, the maximum population density, specific growth rate, protein concentration, and minimum lag phase duration were 15.7 mg/ml, 3.4 h(-1), 0.78 mg/ml, and 4.2 h, and the actual values were 14.3 +/- 3.5 mg/ml, 3.6 +/- 0.6 h(-1), 0.72 +/- 0.2 mg/ml, and 4.4 +/- 1.6 h, respectively.  相似文献   
9.
A new natural product, 2(S),3(S)-3-hydroxy-4-methyleneglutamic acid (G3) has been isolated from seeds of Gleditsia caspica. The structure has been established by chemical and spectroscopic methods. Catalytic reduction of G3 yields 2(S),4(S)-4-methylglutamic acid and a new amino acid, 2(S),3(S),4(S)-3-hydroxy-4-methylglutamic acid. Ozonolysis of G3 followed by oxidation gives 2(S),3(R)-3-hydroxyaspartic acid. The S- (or l-) configurations at C2 in G3 and in 2(S),3(S),4(S)-3-hydroxy-4-methyglutamic acid and the S-configurations at C3 for G3 and 2(S),3(S),4(S)-3-hydroxy-4-methylglutamic acid and at C4 for 2(S),3(S),4(S)-3-hydroxy-4-methylglutamic acid are inferred from the configurations at C2 in 2(S),4(S)-4-methylglutamic acid and at C2 and C3 in 2(S),3(R)-3-hydroxyaspartic acid. The seeds also contain appreciable quantities of 2(S),3(S),4(R)-3-hydroxy-4-methylglutami c acid (G1) and 2(S),4(R)-4-methylglutamic acid.  相似文献   
10.
The ability to generate human induced pluripotent stem cells (iPSCs) has opened new avenues for human disease modelling and therapy. The aim of our study was to determine research participants’ understanding of the information given when donating skin biopsies for the generation of patient-specific iPSCs. A customised 35-item questionnaire based on previous iPSC consent guidelines was sent to participants who had previously donated samples for iPSC research. The questionnaire asked pertinent demographic details, participants' motivation to take part in iPSC research and their attitudes towards related ethical issues. 234 participants were contacted with 141 (60.3 %) complete responses received. The median duration between recruitment and follow-up questioning was 313 days (range 10–573 days). The majority of participants (n = 129, 91.5 %) believed they understood what a stem cell was; however, only 22 (16.1 %) correctly answered questions related to basic stem cell properties. We found no statistically significant difference in responses from participants with different levels of education, or those with a health sciences background. The poor understanding amongst participants of iPSC research is unlikely to be unique to our study and may impact future research if not improved. As such, there is a need to develop an easily understood yet comprehensive consent process to ensure ongoing ethical progress of iPSC biobanking.  相似文献   
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