Showing papers by "University of Haifa published in 1982"
TL;DR: It is determined that the defensive responses used by two agamid lizards, Agama savignyi and A. pallida, change as a function of body temperature.
264 citations
TL;DR: In this article, the geometric structure of compact locally conformal Kahler-flat manifolds is described. And a method for studying analytic vector fields on generalized Hopf manifolds on which a certain canonically defined foliation is regular is presented.
Abstract: Let (M,J,g) be a Hermitian manifold with complex structure J, metric g, and Kahler form Ω. Then g is locally conformal Kahler iff dΩ=ω ∧ Ω for some closed and non-exact 1-form ω. Moreover, if ω is a parallel form, M is called a generalized Hopf manifold. The main results of this paper are: (a) the description of the geometric structure of the compact locally conformal Kahler-flat manifolds; (b) the description of the geometric structure of the compact generalized Hopf manifolds on which a certain canonically defined foliation is regular; (c) a description of the harmonic forms and Betti numbers of a general compact generalized Hopf manifold; (d) a method for studying analytic vector fields on generalized Hopf manifolds; (e) conditions for submanifolds of generalized Hopf manifolds to belong to the same class.
187 citations
TL;DR: The results suggest the operation of natural selection in population genetic structure, local adaptive genetic differentiation caused by diversifying selection through climate and soil, and the guidelines for sampling these resources for use in wheat breeding programs.
Abstract: Allozyme variation in the tetraploid wild progenitor of wheat, Triticum dicoccoides, was studied for the proteins encoded by about 50 gene loci in 457 individuals representing 12 populations from Israel Six spikelet morphological traits were measured in the same populations The results indicate that: (a) 16 loci (= 32%) were monomorphic in all 12 populations, 15 loci (= 30%) were locally polymorphic, and 19 loci (= 38%) were regionally polymorphic All polymorphic loci (but one) displayed high levels of polymorphism (≧ 10%) In Israel, the proportion of polymorphic loci per population, P, in wild wheat averaged 025 (range, 016–038), and the genetic diversity index, He averaged 007, (range, 003 – 012) (b) Altogether there were 110 alleles at the 50 putative loci tested (c) Genetic differentiation of populations included regional and local patterns: (i) The coefficients of genetic distance between populations were high (mean D = 010 range, 002 – 025), and indicated sharp genetic differentiation over short distances, (ii) Common (≧ 10%) but sporadic and localized alleles were frequent (76%), and (iii) Rare alleles were few (only 5 alleles) (d) The patterns of allozyme and spikelet variation in the wild gene pool were significantly correlated with, and partly predictable by, water factors, including those of precipitation, evaporation, and relative humidity as well as of soil type, (e) All six spikelet characters showed statistically significant variation among localities and (f) Allozymic variation was correlated with spikelet variation These results suggest in T dicoccoides: (i) the operation of natural selection in population genetic structure, (ii) local adaptive genetic differentiation caused by diversifying selection through climate and soil, and (iii) the guidelines for sampling these resources for use in wheat breeding programs
177 citations
TL;DR: In this paper, a dynamic incentive generating penalty system was proposed for income tax evasion, which, if instituted, may reduce, at a given cost, the generation of undesirable externalities.
151 citations
TL;DR: In this article, the α-th moment (α > 0) of the KME under a model of proportional hazards was obtained, and the bias of the kme was compared to its asymptotic variance.
Abstract: Whereas much is known about the asymptotic properties of the Kaplan-Meier (1958) estimator (KME) of a survival function, exact results for small samples have been difficult to obtain. In this article, we obtain an exact expression for the αth moment (α > 0) of the KME under a model of proportional hazards. This enables us, under proportional hazards, to (a) study the bias of the KME, and (b) compare the exact variance of the KME to its asymptotic variance.
109 citations
TL;DR: A cyclically controlled method of subgradient projections (CSP) for the convex feasibility problem of solving convex inequalities is presented and a particular application to an image reconstruction problem of emission computerized tomography is mentioned.
Abstract: A cyclically controlled method of subgradient projections (CSP) for the convex feasibility problem of solving convex inequalities is presented. The features of this method make it an efficient tool in handling huge and sparse problems. A particular application to an image reconstruction problem of emission computerized tomography is mentioned.
102 citations
TL;DR: In this paper, a theoretical framework for the development of empirical, logical and mathematical knowledge is presented. But it does not consider the problem of word addition and subtraction in addition.
Abstract: Research conducted in several countries has shown consistent patterns of performance on ‘change’, ‘combine’ and ‘compare’ word problems involving addition and subtraction. This paper interprets these findings within a theoretical framework that emphasizes the development of empirical, logical and mathematical knowledge.
99 citations
TL;DR: Results are inconsistent with the neutral theory of allozyme polymorphisms and appear to reflect the adaptive nature of some Pgi genotypes in these marine gastropods.
Abstract: The effects of zinc and copper pollution on the allozymic variation of phosphoglucose isomerase (Pgi) genotypes were tested in the Mediterranean marine gastropods Monodonta turbinata and M. turbiformis in 26 laboratory tests involving 2 081 adult individuals, with 545 survivors. Our results indicate differential survivorship of electrophoretical Pgi allozyme genotypes for both pollutants. Zinc pollution selected against the allozyme genotype SS in M. turbinata, whereas no differential survivorship was observed in M. turbiformis which lacks this allozyme. Copper pollution selected against the MM genotype in both species. These results are inconsistent with the neutral theory of allozyme polymorphisms and appear to reflect the adaptive nature of some Pgi genotypes in these marine gastropods.
90 citations
TL;DR: In this paper, the problem of time allocation in a labor-managed firm is considered under a technology specification in which the role of management in the production process is different from that of “ordinary” members.
68 citations
TL;DR: In this paper, the Richardson-type iterative method of Cimmino for solving linear equations is generalized to linear inequalities, which includes the generalized CIMMINO scheme, and convergence proofs are provided.
58 citations
TL;DR: In this article, a generalization of the block replacement policy (BRP) is proposed and analyzed, where at failure epochs the replacement of the failed unit is not mandatory and instead a minimal repair can be made.
Abstract: A generalization of the block replacement policy (BRP) is proposed and analysed. The new policy differs from the ordinary BRP in that at failure epochs the replacement of the failed unit is not mandatory and instead a minimal repair can be made. The choice between these two possible actions is based on the repair cost which is assumed to be random. Planned replacements are carried out at timesk T(k=1,2,3….), like in the ordinary BRP, and the aim of the paper is to find the optimal block interval T which minimizes the long run expected cost per unit time of the policy.
TL;DR: Both results appear to be climatically adaptive and support an optimal activity pattern theory assuming that natural selection maximizes fitness by optimizing net energy gain per unit activity.
Abstract: Activity patterns were tested in four actively speciating chromosomal forms of blind subterranean mole rats of the Spalax ehrenbergi complex (2n = 52, 54, 58, and 60) which inhabit humid (2n = 52 and 58) and xeric (2n = 54 and 60), as well as cool (2n = 52 and 54) and warm (2n = 58 and 60) environments, respectively. Experimental animals included 98 adult male mole rats representing 9 populations covering the entire species range in Israel. The test apparatus simulated a natural underground territorial runway of a solitary occupant and each test lasted 24 h. The results indicated that (a) the pattern of activity was multiphasic, but activity in all nine populations is remarkably higher during the day than during the night and (b) differences occur among chromosome forms in both levels and patterns of activity. First, the “humid chromosome forms” are more active than the “xeric chromosome forms” and, second, it appears that the activity of the “cool chromosome forms” display a pattern of smaller number of periods as compared with the “warm chromosome forms.” Both results appear to be climatically adaptive and support an optimal activity pattern theory assuming that natural selection maximizes fitness by optimizing net energy gain per unit activity.
TL;DR: This paper classified policies towards minorities in terms of the three major ways to achieve stability in pluralistic societies: consensus-building, consociationalism, and domination, and the most important measures used to implement this option are the inculcation of shared core values, crosscutting affiliations and resource allocation according to merit.
Abstract: It is possible to classify policies towards minorities in terms of the three major ways to achieve stability in pluralistic societies. These are consensus-building, consociationalism and domination. The policy of consensus -building is reflected in a sustained effort to do away with ethnic divisions, the weakening of primordial ties and the formation of common national culture and identity. The most important measures used to implement this option are the inculcation of shared core values, crosscutting affiliations and resource allocation according to merit. Based on the uni-cultural, uni-national ideal of the nation-state, the consensus-building policy usually takes the form of assimilation, either voluntary or imposed. Typical examples are the policies of Americanizati on and Russification as well as endeavours at nation building by many new states (Eisenstadt and Stein, 1973). In contrast, the policy of consociationalism intends to retain the ethnic division and to legitimize the ethnic cultures and identities. An attempt is made to secure political integration through crystallization of broad operative consensus, compromise in controversial issues while depoliticizing irreconcilable areas and cooperation among the ethnic elites. Rather than individual achievement, proportional group representation is practised to attain equal opportunity. Similarly, legal-cultural self-rule and sometimes territorial autonomy are granted to minorities instead of personal competition and ethnic integration. Consociationalism is carried out with considerable success in the Netherlands and Switzerland, with some headway in Canada and Belgium, but failed in Cyprus and Lebanon (Lijphart, 1977).
TL;DR: The results indicate that populations are largely continuous in their main ranges of distribution and may be viewed on the evidence found as one continuous "megapopulation" within chromosomal species and isolates on the eastern and southern periphery of the range.
Abstract: Theory predicts that population size, structure and distribution may affect the pattern and rate of both speciation and differentiation in the presence of adequate ecological opportunity. Evolutionary change is expected to be much faster in a subdivided population with varying sizes and degrees of isolation of local demes than in a homogeneous population of comparable size, owing to local differential selective pressures and gene flow (Wright, 1931, 1943; Karlin 1976 and references therein). The subdivision of the species into a large number of partially isolated demes increases the importance of random drift compared to an undivided population of the same total size, and amplifies interdeme selection, hence evolutionary change (Wright, 1943). Populations of subterranean herbivore mammals are often assumed to conform to the island model type of distribution due to ecogeographic discontinuities (Wright, 1931), e.g., Cratogeomys castanops and Thomomys bottae (Hansen et al., 1960), Geomys bursarius and G. personatus (Davis, 1940; Kennerly, 1954) and various species of Thomomys (Vaughan, 1967; Patton and Dingman, 1968; Thaeler, 1968). Rapid explosive speciation and differentiation in subterranean rodents is assumed to be causally related to high rate of chromosomal evolution (Bush et al., 1977) presumably due to frequently subdivided small and semi-isolated populations (Nevo, 1979). The objective of the present study was to find out to what extent ecogeographical continuities exist in subterranean mole rats in Israel belonging to the actively speciating superspecies of Spalax ehrenbergi. In other words: is the prolific speciation and adaptive differentiation of Spalax in Israel related to a high geographically subdivided population structure? In general, our results indicate that populations are largely continuous in their main ranges of distribution and may be viewed on the evidence found as one continuous "megapopulation" within chromosomal species and isolates on the eastern and southern periphery of the range.
TL;DR: Orchis galilaea has evolved a pollination mechanism based on a sexual attraction specific for the males of H. marginatus, which is the result of the strong, musk-like scent.
Abstract: SUMMARY The flower of Orchis galilaea (Bornm. et Schulze) Schltr. does not contain nectar. Only the males of Halictus marginatus are attracted and pollinate the orchid; females visit the flowers of other plant families. We suggest that 0. galilaea has evolved a pollination mechanism based on a sexual attraction specific for the males of H. marginatus. This sexual attraction is the result of the strong, musk-like scent.
TL;DR: In this article, the one-way ANOVA model with common variance was considered and the Simultaneous Confidence Intervals (SCI) for monotone contrasts in the means were derived and compared to alternative intervals gene-rated by Williams (1977)
Abstract: The one-way ANOVA model with common variance is considered. Simultaneous confidence Intervals (SCI) for monotone contrasts in the means are derived and compared to alternative intervals gene¬rated by Williams (1977)
TL;DR: This paper explored the question whether grammatical gender loading in the native language will have an effect on the development of gender identity and found that there is a direct relationship between gender loading and gender identity attainment.
Abstract: This study attempted to explore the question whether sex-determined grammatical gender loading in the native language will have an effect on the development of gender identity. The empirical question asked was, Will there be a relationship between the amount of linguistic emphasis on sex-determined gender and the average age of attaining gender identity in children, in a specific language environment? Three groups of children, one in Israel, one in the USA, and one in Finland, were tested on the Michigan Gender Identity Test (MIGIT). The findings indicate a direct relationship between gender loading in the native language and gender identity attainment. It appears that the Israeli children have a significant, albeit temporary, advantage over their American and Finnish counterparts in the timing of gender development.
TL;DR: The male frogs produced the greatest latency periods when stimulated with calls of Hyla arborea arborean, which implies that the Israeli tree frog should be further studied as a possible separate species, HylA savignyi.
Abstract: Calling males of the Israeli tree frog Hyla arborea savignyi maintain a distance of at least 30 cm from one another If a conspecific male comes closer the caller reacts aggressively or falls silent These behavior patterns could also be elicited by simulated mating calls presented at an intensity corresponding to that of the calls of a male 30 cm away As the sound pressure of the simulated calls was progressively reduced, the test frog responded by shifting from territorial calls to mating calls Simulated calls at relatively low intensity which elicited only mating calls evoked calls with the shortest latency when the pulse rate of the simulated signals corresponded to that of the natural mating call or was 20 pulses/s higher The male frogs produced the greatest latency periods when stimulated with calls of Hyla arborea arborea This result implies that the Israeli tree frog should be further studied as a possible separate species, Hyla savignyi
TL;DR: A field experiment was conducted to change current instructional methods in the classroom to cooperative, small-group teaching (SGT) instead of the whole-class, presentation-recitation method as discussed by the authors.
Abstract: A field experiment was conducted to change current instructional methods in the classroom to cooperative, small-group teaching (SGT) instead of the whole-class, presentation-recitation method. Fifty teachers, constituting the majority of the staff in three elementary schools serving a lower class neighborhood in the larger Tel-Aviv, Israel area participated in this experiment which lasted more than 18 months. Findings revealed that: Implementation of SGT occurred during the second year of the project following eight months of workshops and the adoption of teacher self-help teams for monitoring classroom instructional performance. The experimental group registered a significant positive change on an attitude questionnaire indicating a more progressive and less controlling approach to teaching and to education in general. Implementers of small-group learning were found to be less conservative and more willing to take risks, more spontaneous and imaginative, more open to feelings, and more socially oriented ...
TL;DR: In this article, the authors review four approaches regarding the development of altruism and propose an integrative framework, focusing on the biological and social aspects of the altruism process, and the first, the evolutionary approach, the focus is on the biology and social con...
Abstract: The paper reviews four approaches regarding the development of altruism and proposes an integrative framework. In the first, the evolutionary approach, the focus is on the biological and social con...
TL;DR: About 20 adventive wild species in Israel are widespread noxious weeds which now have economic significance in Israel, 20 others are known to have similar ecological tendencies in other countries and soon may become aggressive weeds in Israel.
Abstract: 73 adventive wild species occur in the flora of Israel: 39 are of tropical origin, 20 are North American. The geographical distribution pattern suggests that about two thirds of the species reached Israel through neighbouring countries, while only one third arrived directly from their countries of origin. — Three patterns of population dynamics can be recognized: accidental species (7), colonizing species (30), and species penetrating into natural habitats (3). There is insufficient information about the remaining species. — About 20 species are widespread noxious weeds which now have economic significance in Israel, 20 others are known to have similar ecological tendencies in other countries. These species soon may become aggressive weeds in Israel.
TL;DR: The results are extended to the case where life distrubutions are arbitrary and conditions are given under which there is an optimal replacement policy with a special convenient form.
Abstract: A system e.g., a car must operate for the next t time units. A certain component e.g., a battery must be replaced whenever it fails, as it is essential for the operation of the system. There are several types of components differing only in price and life distribution. The problem of choosing the optimal type at any time in which a replacement is needed has previously been studied when all life distributions are exponential. In this paper the results are extended to the case where life distrubutions are arbitrary. Conditions are given under which there is an optimal replacement policy with a special convenient form. Algorithms for the solution of the problem are provided. Examples and related problems are discussed.
TL;DR: The paper focuses on the attempts to introduce a national health insurance system in Israel and concludes that the issue, torn between conflicting parties, reached a stalemate which is not likely to be resolved in the near future.
TL;DR: In sum, the cloze method appears well adapted to Arabic, and there is no apparent reason to abandon the whole-word method used with English and other languages.
Abstract: The wide gap between written and spoken variants of the Arabic language turns reading comprehension into a criterion of formal learning. The cloze technique for assessing reading comprehension is a promising tool, but it involves a decision as to whether the elision of complete words, as in English, is to be preferred to the elision of semantic units that are whole words in English but compounded in Arabic and certain other languages. In effect, the question is whether Arabic is decoded mainly by way of perceptual or semantic units. Omitted words or semantic units within words, at the rate of every fifth, sixth, or seventh unit, were replaced by 584 Arab pupils in the fifth, sixth, or seventh grades of Arab schools in Israel. Age and frequency-of-omission trends tended to favor the whole-word elision method, while presumed difficulty of passage agreed with the semantic-unit method. The two methods were shown to be equally valid by a criterion of teacher grades. In sum, the cloze method appears well adapted to Arabic, and there is no apparent reason to abandon the whole-word method used with English and other languages.
TL;DR: In this article, the authors examined the social identity of Arabs and Jews in Israel and its relationship to the readiness for establishing and maintaining intergroup contact, and found that the need for social relations with Arabs is weakly related to the identity system.
Abstract: This paper examines the social identity of Arabs and Jews in Israel and its relationship to the readiness for establishing and maintaining intergroup contact. Social identity is defined in terms of self-esteem and the national, civic, religious, familial, residential, and vocational subidentities. The structural coherence of the indentity system was demonstrated for both Jews and Arabs, but while subidentities among Jewish subjects tend to be positively interrelated, there is strain within the Arab system, revealed by a negative correlation between the national and civic subidentities, among others. Readiness for relations with members of the other group is higher for Arabs than for Jews and also more clearly related to several subidentities. Jewish readiness for social relations with Arabs is weakly related to the identity system. Identity variables may be promising mediators between situational antecedents and intergroup attitudes, but mainly for members of the minority.
TL;DR: In this paper, the authors argue for a decision-making orientated science and technology curriculum for secondary school students to expose students to open-ended problems within their natural setting and involve them in scientific-technological social actions, e.g. in community institutions or industrial plants.
Abstract: Summaries English In this article, the author argues in favour of a decision‐making orientated science and technology curriculum for secondary school students. To achieve this, the curriculum should (i) expose students to open‐ended problems within their natural setting, (ii) provide students with real decision‐making situations and (iii) involve them in scientific‐technological social actions, e.g. in community institutions or industrial plants.
TL;DR: It is suggested that each pollinator is attracted by a different nectary type and that the modes of pollination prevent competition between the different pollinators and are to be interpreted as maximizing the floral attraction in the harsh season of fiowering.
Abstract: SUMMARY Sternbergia clusiana is pollinated by two main types of pollinators. Apis mellifera and various Syrphidae. The honey bees collect nectar and pollen from the shorter inner whorl of stamens and from the lowermost part of the funnel-shaped perianth tube. The hover flies visit mainly the appendages on the outer perigone and the longer stamen whorl. These appendages were found to secrete a sugar solution as well as polysaccharides and lipids. The latter probably attract the flies. It is suggested that each pollinator is attracted by a different nectary type and that the modes of pollination prevent competition between the different pollinators and are to be interpreted as maximizing the floral attraction in the harsh season of fiowering (September to December).
TL;DR: The spatial patterns and environmental correlates of genetic and morphological variation in Rana ridibunda in Israel suggest that protein polymorphisms are at least partly adaptive and that part is moulded by natural selection rather than by stochastic processes or neutrality.
Abstract: Allozymic variation in proteins encoded by 28 loci was analyzed electrophoretically in 340 mostly adult specimens representing 11 populations, 8 central and 3 isolated, of aquatic marsh frogs, Rana ridibunda in Israel, along a north-south transect of generally increasing aridity. In addition, geographic variation in 3 morphological variables of 144 frogs and in vertebral stripe color polymorphism of 262 frogs were also studied. The results indicate that. (a) Of the 28 loci examined, 12 (= 43%) are largely monomorphic in all populations; out of the remaining loci, 6 were locally and weakly polymorphic and 10 regionally and strongly polymorphic. (b) No fixation of alternative alleles was found in any of the 28 loci and 11 populations studied. The commonest allele predominated across all populations, central as well as isolates, (c) Clinal patterns associated with increasing aridity southwards and eastwards occurred in polymorphism, P; heterozygosity, H; and in allele frequencies of Esterase-1, Xanthine dehydrogenase, Aldehyde oxidase and Albumin. (d) In the 3 estimates of genie variation, mean number of alleles per locus, A, mean proportion of polymorphic loci per population, P, and heterozygous loci per individual, H, marsh frogs displayed average estimates of genetic variation. The 3 estimates were: A =1.14 (range, 1.18–1.57); P = 0.33 (range, 0.14–0.54): H = 0.069 (range, 0.032–0.094). (e) Central populations harbored distinctly more genic variation than isolated populations. (f) Genic similarity between populations was high. (g) Significant deviations from Hardy-Weinberg equilibrium were found in 8 out of 11 populations involving 8 loci, (h) P, H, and allozymic variation in several gene loci were significantly correlated and predictable by environmental variables, primarily those related to water and temperature. (i) A significant amount of morphological variation was found between localities for body length, foot length, and weight in both sexes. Body weight in females was negatively correlated with temperature; and all three morphological variables in females were predicted significantly by a combination of temperature and humidity. (j) The three vertebral stripe color phenotypes, gray, green and red occurred in the following frequencies: 0.59, 0.24, 0.17, respectively. The red morph increased clinally southwards and was significantly correlated with most temperature and water variables. The geographic variation in both the green and red morphs was predicted significantly by climatic variables, both colors blending with local substrates.
TL;DR: Microgeographic differentiation in proteins, encoded by 30 loci, was tested in 285 individuals comprising 3 species of landsnails in Israel, and differential slope patterns appear to be adaptive, and are presumably maintained by microclimatic diversifying selection.
Abstract: To elucidate the forees maintaining protein polymorphisms, microgeographic differentiation in proteins, encoded by 30 loci, was tested in 285 individuals comprising 3 species of landsnails in Israel. Each test consisted of 2 close subpopulations: one from the drier and warmer south-facing slope and the other from the opposite wetter and cooler north-facing slope. The 5 tests involved 2 of Buliminus labrosus in Mediterranean Count Carmel; 1 of Sphincterochila zonata in the northern, and 2 of S. prophetarum in the central Negev desert. The results indicate significant allele differences between the two slopes in several loci in each of the 5 local tests, involving primarily esterases (Est), aspartate aminotransferase (Aat) and leucine amino peptidases (Lap). The differential slope patterns appear to be adaptive, and are presumably maintained by microclimatic diversifying selection.
TL;DR: Findings contradicted the cultural stereotypes of the macho Israeli male and the nonfeminine Israeli woman and supported the view that the androgynous person's flexibility and adaptability is conducive to a satisfactory sexual relationship.
Abstract: This study investigated the hypothesis that individuals with androgynous personalities would be more competent sexually than individuals with sex-typed personalities. Scores on the Bem Sex-Role Inventory were compared for a patient group and a control group. The data revealed a higher percentage of androgynous subjects in the control group than in the patient group. Even when only one spouse was androgynous, the chances of sexual competence within the couple increased. In addition, there was more sex typing among the longer married patient couples and more stereotyped femininity in both men and women in the patient group. The results were taken to support the view that the androgynous person's flexibility and adaptability is conducive to a satisfactory sexual relationship. Some cultural differences between Israeli and American samples were noted. Findings contradicted the cultural stereotypes of the macho Israeli male and the nonfeminine Israeli woman.