Showing papers by "University of Haifa published in 1978"
TL;DR: Analysis of allozymic variation in natural populations of plants, animals, and humans based on studies published prior to early 1976 and involving 243 species, suggests that the amounts of genetic polymorphism and heterozygosity vary nonrandomly between loci, populations, species, habitats, and life zones, and are correlated with ecological heterogeneity.
964 citations
TL;DR: The test of eight additional loci of blood proteins reinforces earlier conclusions and sheds light on the allozyme–environment association and on the amount of genetic differentiation during speciation.
Abstract: SPECIATION theory is still largely descriptive. How many and what kind of genes are implicated in speciation is a central unresolved problem of evolutionary biology1,2. Does speciation require major genomic changes3–5 or may minor ones suffice1,6–9? Similarly, does speciation depend on structural or on regulatory genes10? We have investigated these questions with reference to the actively speciating fossorial mole rats of the Spalax ehrenbergi complex in Israel, which comprises four morphologically indistinguishable chromosome forms (2n = 52, 54, 58, 60)11 adapted in that order to increasing aridity12. Narrow hybrid zones between karyotypes13 and mate selection14 (through olfaction15, vocalisation16 and aggression17) suggest that the recently18 formed species represent progressive stages of final speciation13. Genic diversity proved low, and genic similarity between karyotypes very high, in the previous test based on 17 gene loci of tissue proteins8. The test of eight additional loci of blood proteins, which is reported here, reinforces earlier conclusions and sheds light on the allozyme–environment association and on the amount of genetic differentiation during speciation.
228 citations
TL;DR: The evidence indicates that natural populations of this species represent very rich reserves of genetic variability, and field sampling and evaluation strategies which stress the sampling of more sites at the expense of reducing numbers per site are supported.
Abstract: In order to evaluate the potential genetic resources of the wild relatives of crop plants, allozyme variation at 28 loci was determined for 28 Israel populations of Hordeum spontaneum, the progenitor of cultivated barley. Etectrophoretic properties of these loci and their variants are described. The enzyme loci exhibited a great range of polymorphism, from one to fifteen alleles per locus being detected. The average probability that two gametes drawn randomly from this collection would differ genetically at a locus was 0.19. The evidence indicates that natural populations of this species represent very rich reserves of genetic variability. The extent of differentiation between populations at each locus was compared with that shown by variation in spikelet morphology. The allozyme diversity was apportioned into 17% between regions, 32% between populations within regions, and 51% within populations. In contrast, spikelet variation occurred predominantly between populations. This indicated the species is highly differentiated in phenotype between regions, and presumably allozyme variation is involved in this differentiation. These results support field sampling and evaluation strategies which stress the sampling of more sites at the expense of reducing numbers per site.
210 citations
TL;DR: The results indicate that extensive genetic polymorphisms found in H. spontaneum probably predates the domestication of the crop, and is maintained independently of introgression.
Abstract: The extent of cross-pollination was estimated quantitatively in 26 populations of wild barley (H. spontaneum) in Israel, using allozyme variation at 22 polymorphic loci. Individual population estimates varied from 0 to 9·6 per cent outcrossing. The overall average was 1·6 per cent, with a 95 per cent confidence range of 0·8-2·7 per cent. The evidence indicated that outcrossing was significantly higher in populations growing in the more mesic (2·1 percent), than in the xeric regions (0·4 per cent). The average frequency of multilocus homozygosity for the 22 loci was 0·963 which was in agreement with the level expected under the observed high rate of self-fertilisation, indicating no heterozygous excess. However, the heterozygotes encountered, displayed a very high degree of multiple heterozygosity which arises from extensive gametic phase (or linkage) disequilibrium. In general, these results do not support the contention that the bulk of the genetic polymorphism found in H. spontaneum in Israel has arisen in recent times by periodic introgression from cultivated barley (H. vulgare L.). Rather they indicate that extensive genetic polymorphisms probably predates the domestication of the crop, and is maintained independently of introgression.
204 citations
TL;DR: This article analyzed the circumstances underlying the rise of a new Arab class formation and the meaning of a struggle for minority rights within Israel where the state employs political and other means, and ideological mystifications, in order to deny the implications of this Arab class and national reality.
Abstract: This is a study in political anthropology. The feudal-bourgeois characteristics of the groups which dominated the Arab national movement and the socialist workers'ideology that was central to Zionism in Palestine during most years of the British mandate are discussed briefly. The main part of the study analyzes the circumstances underlying the rise of a new Arab class formation and the meaning of a struggle for minority rights within Israel where the state employs political and other means, and ideological mystifications, in order to deny the implications of this Arab class and national reality.
72 citations
TL;DR: Two-dimensional pursuit tracking task was employed in three experiments designed to test three predictions of the central capacity model of performance limitations under time-sharing conditions, and the predicted effects of change in task difficulty, task emphasis and their interaction are outlined.
64 citations
TL;DR: Estimates of "average" distances within major population groups suggest that the Ashkenazi Jews are a more homogeneous population than East European non-Jews or than Middle-Eastern populations (Arabs, Armenians, Lebanese and Turks).
Abstract: HLA gene frequencies in 11 Israeli populations and nine other relevant populations were used to calculate genetic distances in a quantitative assessment of their similarities and differences.
The shortest distance found is between Polish and Rumanian Jews, while the largest is between Russian Jews and Black Africans. Estimates of “average” distances within major population groups suggest that the Ashkenazi Jews (Poles, Russians, Rumanians and Germans) are a more homogeneous population than East European non-Jews or than Middle-Eastern populations (Arabs, Armenians, Lebanese and Turks).
A cline of distances between Ashkenazi Jews and other Jewish communities parallels their geographic distribution; however, the relatively large distance between the two North African communities (Libyans and Moroccans) demonstrates that geographic proximity is not necessarily correlated with genetic similarity.
The Jewish populations, especially the Ashkenazi, show a clear divergence from their neighboring non-Jewish populations, among whom they have lived for many centuries.
There are indications in the HLA data of a common origin for the diverse Jewish populations.
63 citations
TL;DR: In this article, the authors investigated the therapeutic feasibility of cognitive self-control manipulation of smoking behavior and found that the Cognitive Self-Control group was significantly more effective in maintaining a reduction in smoking in almost all of the follow-up periods and, after 14 months, was unquestionably superior to the Stimulus Control group.
60 citations
59 citations
TL;DR: It is hypothesized that natural selection presumably favours specific alleles in each site, and that in barnacles different allozymic variants function optimally in different polluted environment.
Abstract: Allozymic variation in proteins encoded by 15 loci was analyzed electrophoretically in 166 individuals of the subtropical acorn barnacleBalanus amphitrite from 3 sites varying in pollution levels, situated within 3 km of one another in the Mediterranean Haifa Bay. The 3 sites respectively were a relatively unpolluted marine bay, a petroleum polluted port, and a petrochemically polluted dockyard. Out of the 15 loci tested, 10 exhibited in both 1974 and 1975 statistically significant repetitive trends in allele frequencies in accord with the 3 sites. It is hypothesized that natural selection presumably favours specific alleles in each site, and that in barnacles different allozymic variants function optimally in different polluted environment.
56 citations
TL;DR: Gc subtypes were determined by immunofixation isoelectric focusing in a family study involving 93 families with a total of 176 children and a three-allele model with six genotypes was confirmed.
Abstract: Gc subtypes were determined by immunofixation isoelectric focusing. In a family study involving 93 families with a total of 176 children, a three-allele model with six genotypes was confirmed. The distribution of Gc subtypes was studied in three populations from Europe and in a sample of Druzes from Northern Israel. Three new variant Gc types were observed.
TL;DR: In this paper, the authors examined the Durkheimian notion of the variation in suicide rates by introducing a time series dimension instead of the cross-sectional method employed in most previous sociological investigations.
Abstract: This study attempted to examine the Durkheimian notion of the variation in suicide rates by introducing a time series dimension instead of the cross-sectional method employed in most previous sociological investigations. The major theoretical thrust of this paper is that social solidarity is not constant, and that socio-economic and demographic forces will affect social solidarity which, in turn, will affect suicide rates. Based on time series data for the U. S. A. for the period 1920–1969, the relationships between suicide rates controlled for sex and race, and unemployment and the ratio of divorce to marriage were examined. The regression analysis produced the following significant findings:
A further refinement of the analysis employed a separate regression analysis for the period 1920–1941 (pre WWII era) and 1946–1969 (post WWII era). This analysis supported the contention that there is a differentiation in sex roles with regard to suicide rates. Thus in the post WWII period whereas neither males nor females (white or non-white) were affected by changes in familial integration, males seemed to respond to economic hardships as measured by unemployment, while females did not. It was also noticed that unemployment lost some of its high predictive power in explaining variations in suicide rates after the war. It is evident that future research is necessary to identify socio-structural variables that can explain changes in female suicide rates. The operationalization of familial integration is a problem, because in different time periods marriage and divorce rates are related differently to suicide rates controlled for sex and race. This also suggests a new perspective for theorizing and data interpretation, namely that the changing socio-cultural connotations of divorce and marriage and unemployment must be considered as intervening variables in the time series analysis of suicide rates.
TL;DR: In this article, aggressive preschool children were instructed by their teacher on the harm that results from aggression, its lack of effects as an interpersonal strategy, and the benefits that result from prosocial alternatives.
TL;DR: In this paper, the authors give a rule for choosing the least costly preventive replacement policy under conditions specified in the paper, where the distribution of item life times is uniform, or 2-stage Erlang.
Abstract: Two widely used preventive replacement policies are the age replacement policy (ARP) and the block replacement policy (BRP). Another replacement policy is the failure replacement policy (FRP) in which no preventive replacements are made at all. In this paper we give a rule for choosing the least costly of the above three policies under conditions specified in the paper. The implementation of this rule is illustrated for two special cases, where the distribution of item life times is uniform, or 2-stage Erlang.
TL;DR: The question of which policy parameters, i.e. control limits and critical ages, to choose when facing a real-life situation is considered, and how to find the optimal parameters which minimize this objective function is shown.
Abstract: A trigger-off replacement policy, suggested and analyzed in [1], for two-unit systems composed of identical units, is generalized and extended in this work in several ways. In the first part of the paper we obtain the appropriate integral equations for nonidentical units and then use them for a complete solution of the case of two units, whose lifetimes are distributed according to general Erlang distributions. In the second part of the paper we extend the trigger-off policy itself by allowing preventive replacements of units which reach a certain critical age. The system stops working if either one of the two units fails or reaches its critical age. Both cases present natural replacement possibilities for the remaining unit, provided that its age exceeds a predetermined critical age.
Finally, we consider the question of which policy parameters, i.e. control limits and critical ages, to choose when facing a real-life situation. Using the criterion of expected costs per unit time in the long run, we show how to find the optimal parameters which minimize this objective function. The fact that a restricted optimization, within the class of trigger-off replacement policies, leads to the global optimal policy has been proved in [2] by a different approach.
TL;DR: In this paper, the authors examined the effect of institutionalized general turnover and internal rotation of managerial personnel and its effects on the conduct of the organizations involved with data from production branches of Israeli kibbutzim.
Abstract: The phenomenon of institutionalized general turnover and internal rotation of managerial personnel and its effects upon the conduct of the organizations involved is examined with data from production branches of Israeli kibbutzim. Arguments for and against the effectiveness of such a norm are presented. Four specific hypotheses are formulated. About 60 productive organizations were involved: 33 farm branches and 27 industrial plants. Data were collected by way of questionnaires to all workers at each organization and by way of documents and interviews with informants. The major findings are the following: The potential for managerial positions is larger than needed for a given time; in the branches studied the median time in office was about 2-3 years. Organizations that practice rotation are not less (and maybe more) effective than those that do not practice rotation. This is because their workers are more involved, knowledgable, and creative than those in the latter. Length of time in office sometimes a...
TL;DR: In this paper, the existence of a conceptual hierarchy of dimensions in which time dominates space and space dominates every other dimension has been investigated, and several observations about the way humans conceive of attributes, changes and covariation of stimuli are presented as indications for the existence in human perception of time and space.
TL;DR: The Sapir-Whorf hypothesis is much in vogue again, after having been dormant for more than a generation as mentioned in this paper, and the current tilt in contemporary psychology toward cognitive interests offers an explanation.
Abstract: Twenty three Israeli kindergarteners and sixteen Israeli college students were tested on a variant of the Semantic Differential Test developed by Guiora (1976) to test the hypothesis that young Israeli children, like adults, are not influenced by the prevalence of grammatical gender in the language but ascribe sexual meanings to the test words based on their assumed connotative values. The results bore out the original hypothesis, suggesting that whatever the cognitive processes are that underlie the development of the capacity to resolve seemingly conflicting information in favor of the more salient feature, e.g. meaning, they seem to be in place by the time the child reaches five years of age. The Sapir-Whorf hypothesis is much in vogue again, after having been dormant for more than a generation. Perhaps, the current tilt in contemporary psychology toward cognitive interests offers an explanation. Language and thought-are they two interdependent phenomena, or two sides of the same phenomenon? This seems to be a question intriquing many psychologists. The attractiveness of Whorf’s position lies in its boldness and imaginativeness. According to John Carroll (Whorf 1956: 26) “Whorf appeared to believe, indeed, that the content of thought influences the process of thought, or that different contents produce differing species of process, so that generalization about process becomes impossible without content’s being taken into account”. This line of reasoning leads of course to what has
TL;DR: The political factors and processes that led eventually to legislation legalizing abortion in israel are discussed and analyzed and the case of abortion is presented as illustrative of public policy formation processes in the Israeli government.
Abstract: The political factors and processes that led eventually to legislation legalizing abortion in israel are discussed and analyzed. The support of the labor organization the Black Panthers the civil rights movement the feminist movement the Minister of Health and the chairperson of the legislative body contributed to promote the legalization of abortion. Opposing forces included religious ideologies (which play a major role in Israeli politics) a pronatalist national policy and physicians (who were however accused of profiting from illegal abortions). Abortion may now be applied for in cases where pregnancy poses a threat to the health or well-being of the pregnant woman or her family and is subject to approval by a committee consisting of 1 gynecologist 1 general practitioner and social worker. The case of abortion is presented as illustrative of public policy formation processes in the Israeli government.
TL;DR: Causative factors such as hunting-gathering adaptation, the evolution of the brain, sexual division of labor and demorphism seem to fit the theory of parental investment when they are combined in an autocatalytic process.
TL;DR: The mortality rate of experimentally wounded fish kept in sea water treated with ultraviolet radiation was significantly lower than that of controls, and bacterial population in a marine fish hatchery reduced, but the larval mortality did not decline.
TL;DR: The use of closed circuit television as a critical component in the process of in-service teacher training for implementing alternative teaching methods and the evaluation plan is described.
Abstract: This paper reports on the use of closed circuit television as a critical component in the process of in-service teacher training for implementing alternative teaching methods. A five-step problem s...
TL;DR: A research method for developing complex applied models which does not sacrifice the high degree of flexibility that such development requires, particularly in relation to Campbell and Stanley's factors of external and internal validity.
Abstract: This article describes a research method for developing complex applied models which does not sacrifice the high degree of flexibility that such development requires. The method involves a detailed and concrete description of one's intervention model, followed by a carefully documented and measured application. The model is then evaluated and modified in the light of the data, and reapplied. This cycle is repeated many times. The requirements and problems of this method are discussed, particularly in relation to Campbell and Stanley's factors of external and internal validity.
TL;DR: The authors examined the manner in which the probability of delaying gratification is affected by the exchange values and the appetitive values of the rewards offered, and found that the tendency to delay gratification is directly related to the exchange value of rewards offered but inversely related to their appetitive value.
Abstract: This study examined the manner in which the probability of delaying gratification is affected by the exchange values and the appetitive values of the rewards offered. Several delay-of-gratification questions were used, requiring a choice between an early small reward and a reward twice as great due at a later time. A total of 6,799 fourth- and sixth-grade Israeli public school pupils participated in the study. Results consistent across sexes, grades, and two delay conditions (“now” versus “in a week from now” and “in a week” versus “in a month”) indicated that the tendency to delay gratification is directly related to the exchange values of the rewards offered but inversely related to their appetitive values. Several implications of these results for the Value X Expectancy model of delay behavior were discussed.
TL;DR: A scale measuring attitudes toward small-group teaching was administered to 442 teachers from 28 elementary and secondary schools in Israel as discussed by the authors, and at least two dimensions of attitudes were identified: control over class and efficiency of the method, each has been shown to have internal consistency and incremental validity with respect to a set of external variables.
Abstract: A scale measuring attitudes toward small-group teaching was administered to 442 teachers from 28 elementary and secondary schools in Israel. At least two dimensions of attitudes were identified: control over class and efficiency of the method. Each has been shown to have internal consistency and incremental validity with respect to a set of external variables.
TL;DR: Writing in Hebrew contributed to a better learning situation consisting of additional time left for individual practice, removal of students' frustration in not being able to say what they want, and the feeling on the parts of both student and teacher that comprehension has been assessed fairly.
TL;DR: This paper considers an adjoint convex problem Θ, which is obtained from Θ by lifting all resource constraints by estimation of resource requirements, and understands construction of such estimates which are valied for every Θ-feasible schedule.