Articoli di riviste: "Inter-fertility"

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Worthman, Carol M., Carol L. Jenkins, Joy F. Stallings e Daina Lai. "Attenuation of nursing-related ovarian suppression and high fertility in well-nourished, intensively breast-feeding Amele women of lowland Papua New Guinea". Journal of Biosocial Science 25, n. 4 (ottobre 1993): 425–43. http://dx.doi.org/10.1017/s0021932000021817.

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SummaryIntense, sustained nursing lengthens inter-birth intervals and is causally linked with low natural fertility. However, in traditional settings, the effects of such nursing on fertility are difficult to disentangle from those of nutrition. Results from an prospective, direct observational study of reproductive function in well-nourished Amele women who nurse intensively and persistently but who also have high fertility are here presented. Endocrine measures show that ovarian activity resumes by median 11·0 months postpartum. Median duration of postpartum amenorrhoea is 11·3 months, time to next conception is 19·0 months, and the inter-birth interval is 28·0 months. Average life time fertility is 6·8. High fertility in Amele women is due both to refractoriness of reproductive function to suckling stimuli, and to maintenance of equivalent age-specific fertility rates across the reproductive life span.

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Moutier, N. "SELF-FERTILITY AND INTER-COMPATIBILITIES OF SIXTEEN OLIVE VARIETIES". Acta Horticulturae, n. 586 (ottobre 2002): 209–12. http://dx.doi.org/10.17660/actahortic.2002.586.38.

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Abraham, OG, JO Faluyi e CC Nwokeocha. "Inter-varietal sterility and fertility restoration in Oryza sativa Linn." Oryza-An International Journal on Rice 58, n. 4 (31 dicembre 2021): 463–76. http://dx.doi.org/10.35709/ory.2021.58.4.2.

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This study explored the underlining reproductive factors that cause sterility in rice, using hybrids obtained from crosses among landrace selections and improved varieties. The study was carried out between 2016 and 2018. Nine landrace cultivars and two improved varieties were involved in the hybridization experiment. Among the 17 putative hybrids that were obtained, only 5 were confirmed as true hybrids. Meiotic chromosome studies and pollen studies in the F1, and Mendelian segregation studies for fertility in the F2 were carried out. Some F2 lines were monitored to F3 to ascertain the level of fixation of gene combinations for fertility. The results obtained from the chromosomal studies showed that phenomena such as laggards, precocious movements, formation of multivalents, and unequal segregation to the poles are associated with pollen sterility in all - 5 hybrids, at the F1 and F2 generations. The indehiscence of anthers contributed to infertility due to pollen shortage than the fertility of the pollens themselves. Even though in males, there is a preponderance of male sterility, female sterility is also a phenomenon that is possibly contributing to inter-varietal sterility. The segregational pattern of 13:3 was observed for fertility in the F2 which suggests the inhibition of fertility by a gene in the dominant state. There was the restoration of fertility in many of the lines advanced to the F3 to up to 93 % fertility. It was, therefore, concluded from the study that landraces of rice still hold the key for the rice crop improvement and should therefore be conserved.

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Visconti, Fernando, Enrique Peiró, Carlos Baixauli e José Miguel de Paz. "Spontaneous Plants Improve the Inter-Row Soil Fertility in a Citrus Orchard but Nitrogen Lacks to Boost Organic Carbon". Environments 9, n. 12 (4 dicembre 2022): 151. http://dx.doi.org/10.3390/environments9120151.

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The inter-row soils in conventionally run citrus orchards in Eastern Spain lose fertility, either physically, chemically, or biologically, as a consequence of machinery traffic and the use of herbicides. In order to regain inter-row soil fertility, two grass-cover management alternatives to the commonly used herbicide-kept bare management, namely, spontaneous plants and fescue, were established and left for four years until their effects on several physical, chemical, and biological parameters were monitored for two years more. The fescue ground cover exhibited lower average and maximum soil temperatures due to higher evapotranspiration rates but also higher annual soil water content on average and, additionally, higher rhizodeposition. Despite the fact that these new beneficial conditions helped enhance the soil’s biological fertility under fescue, the physical or chemical fertilities did not improve and neither did the organic carbon (SOC). The spontaneous plants also enhanced the biological fertility, but in this case, beneficial conditions were reflected by improvements in the chemical fertility, particularly the exchangeable potassium, and in the physical fertility by increasing the surface hydraulic conductivity and decreasing the bulk density. In the inter-rows of this citrus orchard, a seeded grass cover does not seem able to provide any soil fertility enhancement in comparison to a spontaneous one; rather the opposite. However, a lack of natural or man-driven nitrogen inputs poses a constraint to SOC gains. For this aim, the annual surface application of organic nitrogen-rich materials or even better, the fostering of N-fixing organisms would be recommended.

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Veres, Valér. "Fertility among Hungarian population in Romania; an inter-regional comparative perspective". Erdélyi Társadalom 2, n. 1 (2004): 69–96. http://dx.doi.org/10.17177/77171.30.

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Using the tools of statistical analysis, the author investigates the tendencies of fertility of Romania’s population, especially among the Hungarians in Romania, and its determinants. The main conclusion of his analysis is that the regional differences is the key independent variable of fertility variations, and the ethnic-cultural patterns are only secondary. The analyses were necessary as one could believe that etno-cultural differences influence fertility

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Irwin, Sarah. "‘Reproductive Regimes: Changing Relations of Inter-dependence and Fertility Change’". Sociological Research Online 5, n. 1 (maggio 2000): 85–98. http://dx.doi.org/10.5153/sro.445.

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Within sociological and demographic research many argue that recent demographic transformations can be explained, at least in part, by a growth in individualism. Such approaches, with their emphasis on growing individual autonomy, offer a model of human action in which the social recedes from analysis. This paper offers an alternative framework for analysing processes shaping demographic change, taking as a particular focus aspects of changing patterns of fertility in the UK. Interpretations of the fertility decline at the turn of the twentieth century emphasise the importance of changing patterns of inter-dependence across generations and between women and men. It is argued that in parallel, although to a lesser degree, recent decades have manifest a change in the social positioning of these groups. Change in the reproductive regime is offered as a concept for denoting this restructuring of inter-dependencies. We are witnessing a reconfiguration of social ties and not their displacement. It is as an integral part of such changes that developments in fertility are best interrogated.

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Zhao, Weibo, Wei Zhou, Han Geng, Jinmei Fu, Zhiwu Dan, Yafei Zeng, Wuwu Xu, Zhongli Hu e Wenchao Huang. "Identification of a New Wide-Compatibility Locus in Inter-Subspecific Hybrids of Rice (Oryza sativa L.)". Agronomy 12, n. 11 (15 novembre 2022): 2851. http://dx.doi.org/10.3390/agronomy12112851.

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As a special class of rice germplasm, wide-compatibility varieties (WCVs) guarantee the fertility of hybrids when there is cross-fertilization between two subspecies. In this study, Chenghui9348 was identified as a new member of the WCV family that improves pollen fertility in an inter-subspecific hybrid. Cytological analysis showed that the abnormal mitosis of microspores resulted in the sterility of pollens at the early bicellular stage in the inter-subspecific hybrid. Furthermore, the new F12 locus, corresponding to improvements in fertility of the indica-japonica hybrid, was found to co-segregate with the RM1047 marker and associated with a region of approximately 630 kb flanked by the D1101 and D1164 markers on chromosome 12. In this region, two putative genes were predicted as the candidates for wide-compatibility genes (WCGs). Sequence analysis revealed that, compared with indica/japonica alleles, deletion/insertion occurred within exons of both putative genes. Together, the present study identified another new WC locus, F12, and offers more opportunities for further exploitation of inter-subspecific hybrids in rice.

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Oliveira, Jaqueline. "The value of children: Inter-generational support, fertility, and human capital". Journal of Development Economics 120 (maggio 2016): 1–16. http://dx.doi.org/10.1016/j.jdeveco.2015.12.002.

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Osei-Appaw, Akosua, e Aaron Christian. "The Demographic Dividend As A Pathway To Development: The Role of Fertility and Education in Sub-Saharan Africa. A Narrative Review". International Journal of Economics 7, n. 1 (29 ottobre 2022): 76–90. http://dx.doi.org/10.47604/ijecon.1680.

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Purpose: Sub-Saharan African countries are experiencing rapid population growth. This is essential in achieving the Demographic Dividend. Age structure, fertility and education play a key role in the achievement of the Demographic Dividend. Although gains from age structure are crucial, its gains are not automatic. However, the inter-relatedness of fertility and education makes a reduction in fertility a cause and effect on investments in education. Methodology: This narrative review looks at studies discussing the Demographic Dividend from a development theory point of view. It is an attempt to explain how different countries within Sub-Saharan Africa are faring due to the inter-play between fertility and education. Findings: The results highlight how the Demographic Dividend is really an Educational Dividend. It also shows a negative correlation between education and fertility across regions and time. The political environment with emphasis on good governance plays a key role in harnessing the Demographic Dividend. Aside this, a fertility decline alone could worsen the existing economic conditions if it is not in tandem with higher education rates among young adults. This is in line with Ester Boserup’s view of seeing population as a resource. Unique contribution to theory, practice and policy (recommendation): A conducive political environment attracts investments and creates room for entrepreneurship and job creation which are necessary to be able to harness the Demographic Dividend. There’s the need to however, look at the definition of working age group and conditions necessary to promote entrepreneurship.

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Royal, M. D., A. O. Darwash, A. P. F. Flint, R. Webb, J. A. Woolliams e G. E. Lamming. "Declining fertility in dairy cattle: changes in traditional and endocrine parameters of fertility". Animal Science 70, n. 3 (giugno 2000): 487–501. http://dx.doi.org/10.1017/s1357729800051845.

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AbstractReproductive performance of 714 Holstein Friesian dairy cows was monitored between October 1995 and June 1998 using thrice weekly milk progesterone determinations. Defined endocrine parameters such as interval topost-partumcommencement of luteal activity, inter-ovulatory interval and length of luteal and inter-luteal intervals were used with a number of traditional measures of reproductive performance to investigate the current status of fertility in a sample of United Kingdom dairy herds. A comparison of the results of the 1995 to 1998 trial with those of a previous (1975 to 1982) milk progesterone database, which included 2503 lactations in British Friesian cows monitored using a similar milk sampling protocol, revealed a decline infertility between these periods.Between 1975-1982 and 1995-1998, pregnancy rate to first service declined from 55·6% to 39·7% (P< 0·001), at a derived average rate approaching 1% per year. This decline was associated with an increase (P< 0·001) in the proportion of animals with one or more atypical ovarian hormone patterns from 32% to 44%. There was a significant (P< 0·001) increase in the incidence of delayed luteolysis during the first cyclepost partum(delayed luteolysis type I; 7·3% to 18·2%) and during subsequent cycles (delayed luteolysis type II; 6·4% to 16·8%), although the incidence of prolonged anovulation post partům (delayed ovulation type I; 10·9% to 12·9%) and prolonged inter-luteal intervals (delayed ovulation type II; 12·9% to 10·6%) did not alter significantly. These changes resulted in an increase in mean luteal phase length from 12·9 (s.e. 0·09) to 14·8 (s.e. 0·17) days and an increase in inter-ovulatory interval from 20·2 (s.e. 0·1) to 22·3 (s.e. 0·2) days. The decline infertility was also reflected in traditional measures of fertility since although interval to first service remained relatively unchanged (74·0 (s.e. 0·4) to 77·6 (s.e. 1·1) days) calving interval lengthened from 370 (s.e. 2·2) to 390 (s.e. 2·5) days. Collectively these changes may have contributed to the decline in pregnancy rates observed over the last 20 years.

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Idris, Asma' Rashidah, Muzafar Shah Habibullah e Ranjanee Kaliappan. "The Effect of Demographic Change on Financial Stability". Jurnal Intelek 14, n. 2 (29 novembre 2019): 80–93. http://dx.doi.org/10.24191/ji.v14i2.222.

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This study investigates the effect of fertility on financial stability and its determinant particularly therelevance of demographic changes. This is motivated by the huge impact of demographic changes(increasing ageing population and low fertility level). Population ageing and low fertility tend to lowerboth labour- force participation and saving rates (change bank business model), thereby raising concernson a future slowing economic growth and financial instability. The system GMM results show that thefertility level somehow acts as a buffer and reflects to the degree of stability to the financial system. Anincrease in fertility and old-age population will contribute to lowering the financial stability. As a matterof policy implication, the nations, financial sectors, and economies should take pro-active active stepsand enhance policies in handling the inter-related issue of the ageing population, decreasing fertility, andfinancial stability especially in developed countries, but not necessarily to overlook the impact of theissues in developing countries. Keywords: Demographic change, old-age population, fertility, financial stability

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Acharya, Rajib. "Gender Disparity, Development and Fertility Transition in India: An Inter-State Analysis". Journal of Social Sciences 2, n. 4 (ottobre 1998): 253–63. http://dx.doi.org/10.1080/09718923.1998.11892213.

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Messkoub, Mahmood. "Population ageing and inter-generational relations in the MENA: what role for social policy?" Population Horizons 14, n. 2 (1 dicembre 2017): 61–72. http://dx.doi.org/10.1515/pophzn-2017-0005.

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Abstract Declining fertility and rising life expectancy combined with migration are changing the demographic landscape of the MENA. Earlier high fertility will ensure a growing population in the next 20-30 years. Family structure is also changing: families are becoming smaller and increasingly nuclear, rather than extended. The region has to manage a young age structure and a gradual ageing of the population but with a potential weakening of the traditional inter-generational support based on family, it also faces a widely varying and heterogeneous resource base and socio-economic structure across the different countries. To maintain and improve inter-generational support within family and society in the MENA countries with large populations (such as Iran and Egypt) the most important challenges are poverty and vulnerability, unemployment, and development of long-term plans for an ageing population. These are inter-connected objectives since reducing poverty and increasing current employment could provide individuals and families with some resources to save and accumulate for old age. States in the region should put redistributive social policies in the areas of health, education and housing at the heart of a strategy of supporting family budgets and resources to assist them in their inter-generational care, but should also set up care and pension schemes to provide societal intergenerational support.

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Rigal, Jocelyne. "The Emergence of Fertility Control among Irish Travellers". Irish Journal of Sociology 3, n. 1 (maggio 1993): 95–108. http://dx.doi.org/10.1177/079160359300300105.

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This paper examines the emergence of fertility control among Irish Travellers with a focus on its wider cultural and inter-personal implications. Relying on unstructured interviews and participant observation conducted among Traveller women, this emergence is located in the context of another development, the rise of an ideal family size. Traveller women's uptake of and attitudes towards contraception are analysed and their perceptions of their husbands' resistance to fertility control is documented. The findings highlight the role of gender in cultural change among travellers.

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Jakubowska, Zuzanna, Karolina Koza, Wojciech Leder, Aleksandra Owczarczyk, Zuzanna Skorupka e Tomasz Wróblewski. "The Power of Fertility and Its Importance for the Concept of Sustainable Development". Studia Ecologiae et Bioethicae 19, n. 3 (4 ottobre 2021): 25–35. http://dx.doi.org/10.21697/seb.2021.19.3.03.

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Demographic changes are one of the indicators of sustainable development, expressed by the value of the natural increase in the human population, resulting directly from the fertility level, which is the subject of this article. Human fertility is a complex potential conditioned by the environmental, social, and economic factors. The multi-dimensional relations of fertility that may affect its level, constitute an unlimited field of research, study, and analysis. The inter-disciplinary scope of fertility research conducted by the authors has shown that fertility is an issue that, in its historical, social, political, and medical aspects, has the potential of contributing to societal development and raising the standard of living. The aim of this article is to answer the question: whether and how the fertility of an individual has an impact on the idea of sustainable development. To achieve this, the available literature was analysed and synthesised, as well as supplemented with information provided by experts in the field. The article incorporates presentations of selected fertility determining factors, methods of measuring fertility potential, and diverse contexts, such as the impact of fertility on history and its relationship with the freedom of the human individual. Moreover, the authors present the relationship between the fertility of an individual, and the assumptions and postulates of the idea of sustainable development.

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Maftukh, Muhammad Abdul Khafidz, Lutfi Agus Salim e Farizah Mohd Hairi. "FERTILITY RATE USING THE PALMORE FORMULA IN EAST JAVA PROVINCE: A STUDY OF 2015 SUPAS". Jurnal Biometrika dan Kependudukan 10, n. 2 (31 ottobre 2021): 138. http://dx.doi.org/10.20473/jbk.v10i2.2021.138-143.

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Fertility is an important indicator for the success of state development, especially in the health sector. It can be estimated through direct and indirect methods. This study aimed to determine the fertility rate in East Java province indirectly using the Palmore Formula. This study was a descriptive analysis using secondary data from the 2015 Inter-census Population Survey / Survei Penduduk Antar Sensus (SUPAS). It calculated the rate directly and manually. The Total Fertility Rate (TFR) was at 2.02 per two children born by each mother in East Java province. It was compared with the national average published by the Central Bureau of Statistics within 5 periods of SP1990, SUPAS 1995, SP2000, SUPAS 2005, and SP2010. In each period, the rate was lower without any difference. The Palmore Formula is considered a good method for estimating fertility rates.

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Jennings, Julia A., Allison R. Sullivan e J. David Hacker. "Intergenerational Transmission of Reproductive Behavior during the Demographic Transition". Journal of Interdisciplinary History 42, n. 4 (febbraio 2012): 543–69. http://dx.doi.org/10.1162/jinh_a_00304.

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New evidence from the Utah Population Database (updp) reveals that at the onset of the fertility transition, reproductive behavior was transmitted across generations—between women and their mothers, as well as between women and their husbands' family of origin. Age at marriage, age at last birth, and the number of children ever born are positively correlated in the data, most strongly among first-born daughters and among cohorts born later in the fertility transition. Intergenerational ties, including the presence of mothers and mothers-in-law, influenced the hazard of progressing to a next birth. The findings suggest that the practice of parity-dependent marital fertility control and inter-birth spacing behavior derived, in part, from the previous generation and that the potential for mothers and mothers-in-law to help in the rearing of children encouraged higher marital fertility.

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Casterline, John B. "Demographic Transition and Unwanted Fertility: A Fresh Assessment (The Mahbub Ul Haq Memorial Lecture)". Pakistan Development Review 48, n. 4I (1 dicembre 2009): 387–421. http://dx.doi.org/10.30541/v48i4ipp.387-421.

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The distinction between wanted and unwanted fertility has been crucial in many of the more intense debates in recent decades over the nature of contemporary fertility declines and, in particular, the potential impact of expanded provision of family planning services. In a much-debated article published in 1994, Pritchett argues that decline in desired fertility is overwhelmingly the principal source of fertility decline, with the implication that family planning programmes are of little consequence. I revisit this debate drawing on a far larger body of survey data and, more importantly, an alternative fertility specification which relies on a non-conventional definition of wanted and unwanted fertility rates and which distinguishes rates and composition. Decompositions of fertility decline in the period from the mid-1970s to the present are carried out for 44 countries. The decomposition results indicate that declines in unwanted fertility rates have been at least as important, if not more important, than declines in wanted fertility rates. Surprisingly, shifts in the proportion of women wanting to stop childbearing—i.e., changes in preference composition—has contributed very little to fertility change in this period. Further, decline in wanted fertility and increases in non-marital exposure (due largely to delayed entry into first marriage) have also made substantial contributions, although on average they fall short of the contribution of declines in unwanted fertility rates. That declines in unwanted fertility have been an essential feature of contemporary fertility decline is the main conclusion from this research. This in turn opens the door to new perspectives on fertility pre-, mid-, and post-transition which recognises the inter-dependencies between fertility demand and unwanted fertility rates in the determination of the overall level of fertility. JEL classification: J11, J13, R11 Keywords: Demography, Fertility, Family Planning, Regional Economics

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Azarnert, Leonid V. "MIGRATION, CONGESTION, AND GROWTH". Macroeconomic Dynamics 23, n. 8 (29 giugno 2018): 3035–64. http://dx.doi.org/10.1017/s1365100517001043.

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This article analyzes the effect of migration from a less advanced economy to a more advanced economy on economic growth. The analysis is performed in a two-country growth model with endogenous fertility, in which congestion diseconomies are incorporated. The model shows that out-migration increases fertility and reduces human capital in the source economy. At the same time, in-migration reduces fertility and can increase or decrease the average level of human capital in the host economy. I show how migration affects the inter-temporal evolution of human capital in the world economy. I also demonstrate that a tax imposed on immigrants in the host economy can increase human capital accumulation in the receiving and sending economies and the world as a whole.

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Galindo, David Javier, Gabriela Siqueira Martins, Miluse Vozdova, Halina Cernohorska, Svatava Kubickova, Agda Maria Bernegossi, Dita Kadlcikova, Jiri Rubes e José Maurício Barbanti Duarte. "Chromosomal Polymorphism and Speciation: The Case of the Genus Mazama (Cetartiodactyla; Cervidae)". Genes 12, n. 2 (26 gennaio 2021): 165. http://dx.doi.org/10.3390/genes12020165.

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Chromosomal polymorphism plays a major role in speciation processes in mammals with high rates of karyotypic evolution, as observed in the family Cervidae. One remarkable example is the genus Mazama that comprises wide inter- and intra-specific chromosomal variability. To evaluate the impact of chromosomal polymorphisms as reproductive barriers within the genus Mazama, inter-specific hybrids between Mazama gouazoubira and Mazama nemorivaga (MGO × MNE) and intra-specific hybrids between cytotypes of Mazama americana (MAM) differing by a tandem (TF) or centric fusion (Robertsonian translocations—RT) were evaluated. MGO × MNE hybrid fertility was evaluated by the seminal quality and testicular histology. MAM hybrids estimation of the meiotic segregation products was performed by sperm-FISH analysis. MGO × MNE hybrids analyses showed different degrees of fertility reduction, from severe subfertility to complete sterility. Regarding MAM, RT, and TF carriers showed a mean value for alternate segregation rate of 97.74%, and 67.23%, and adjacent segregation rate of 1.80%, and 29.07%, respectively. Our results suggested an efficient post-zygotic barrier represented by severe fertility reduction for MGO × MNE and MAM with heterozygous TF. Nevertheless, RT did not show a severe effect on the reproductive fitness in MAM. Our data support the validity of MGO and MNE as different species and reveals cryptic species within MAM.

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Tomassetti, C., C. Bafort, C. Meuleman, M. Welkenhuysen, S. Fieuws e T. D'Hooghe. "Reproducibility of the Endometriosis Fertility Index: a prospective inter‐/intra‐rater agreement study". BJOG: An International Journal of Obstetrics & Gynaecology 127, n. 1 (31 luglio 2019): 107–14. http://dx.doi.org/10.1111/1471-0528.15880.

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Borooah, Vani K. "The politics of demography: a study of inter-community fertility differences in India". European Journal of Political Economy 20, n. 3 (settembre 2004): 551–78. http://dx.doi.org/10.1016/j.ejpoleco.2003.10.002.

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Gipson, Jessica D., e Andrew L. Hicks. "THE DELINKING OF SEX AND MARRIAGE: PATHWAYS TO FERTILITY AMONG YOUNG FILIPINO WOMEN". Journal of Biosocial Science 49, n. 1 (26 gennaio 2016): 1–14. http://dx.doi.org/10.1017/s0021932015000462.

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SummaryPartnership and fertility patterns of young Filipinos have changed dramatically from previous generations, with a widening gap between sexual initiation and marriage, and concurrent increases in teenage pregnancy and unwanted fertility. Further understanding of young adults’ social contexts and partnership patterns are needed to inform reproductive health programmes and policies affecting young Filipinos. Multivariate Poisson regression models were conducted with longitudinal and inter-generational data from the Cebu Longitudinal Health and Nutrition Survey (1998–2009) to examine the predictors of young women’s fertility. Age at first sex, and number and duration of partnerships each independently and significantly predicted women’s fertility by 2009 after controlling for contextual influences. Young women with more conservative attitudes towards dating, sex and marriage, and who perceived their mothers to have more conservative attitudes, had higher fertility than their peers, as did young women with mothers who reported more adolescent sexual behaviours. In contrast, fertility was lower among daughters who had higher levels of communication with their mothers. Given high levels of unintended fertility and teenage pregnancy in the Philippines, the findings indicate that the interval between sexual initiation and first and subsequent partnerships may be ideal intervention points for reproductive health services for young Filipinos.

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Kamanová, Vendula, Pavel Nevrkla e Zdeněk Hadaš. "Effect of Breed on Frequency of Morphological Defects in Boar Spermatozoa". Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis 66, n. 3 (2018): 665–68. http://dx.doi.org/10.11118/actaun201866030665.

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The aim of this study was to assess an effect of breed on frequency of morphological changes in boar spermatozoa. A total of 1080 semen samples were used in this study. The samples were collected from January to December 2017 from 90 boars of the Duroc, Czech Large White and Czech Landrace breeds. Sperm cell abnormalities were evaluated microscopically from dyed smears of native semen on glass slides. Defects of spermatozoa were divided according to their impact on fertility of boars into categories of “major defects” (with a great negative effect on fertility) and “minor defects” (with a mild effect on fertility). The overall frequency of spermatozoa with morphological defects ranged from 11.62 % in Czech Landrace to 20.96 % in Duroc. Statistically significant differences were found in the frequencies of both major and minor defects among the breeds. The results of this study document that there are great inter‑breed differences in the occurrence of morphologically defective spermatozoa that significantly affect fertility of boars.

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WILEY, ANDREA S. "THE ECOLOGY OF LOW NATURAL FERTILITY IN LADAKH". Journal of Biosocial Science 30, n. 4 (ottobre 1998): 457–80. http://dx.doi.org/10.1017/s002193209800457x.

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The existence of very low rates of fertility among non-contracepting human populations has intrigued researchers in demography and reproductive ecology. Long inter-birth intervals, driven primarily by the lactational amenorrhoea associated with breast-feeding, have been shown to be important determinants of low natural fertility in several populations. Other reports have suggested that sterility brought about by sexually transmitted diseases (STDs) might also explain low fertility in some populations, especially in Africa. This report presents an analysis of 1981 Indian census data that documents low natural fertility in Ladakh, a high-altitude region of the Himalaya in north India. In Ladakh, there is evidence for low rates of marriage among women that may be attributable to the practice of polyandry, but also high rates of primary and secondary sterility within marriage, resulting in low completed parities for post-reproductive age married women. Age-specific fertility rates derived from the number of current births are also unexpectedly low. Hypotheses to explain very low fertility in Ladakh are considered from among the likely proximate determinants and evaluated using two supplementary sources of information derived from fieldwork in Ladakh in the early 1990s. The most likely explanations for low marital fertility include sterility from STDs, high rates of fetal loss, and possibly nutritional contraints on ovarian hormone status.

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Dallakyan, G. A., E. F. Isakova e D. M. Gershkovich. "SHUNGITE ACTION ON CRUSTACEANS AND ITS INFLUENCE ON POTASSIUM DICHROMATE TOXICITY". Toxicological Review, n. 5 (28 ottobre 2016): 53–58. http://dx.doi.org/10.36946/0869-7922-2016-5-53-58.

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It is shown that at the direct contact with shungite (10.00 and 100.00 g/l) as well as in the presence of shungite isolated on the dialysis sac (100.00 g/l), the survival and fertility of Daphnia magna decrease as compared to the control during 10 days of observation. Shungite effect is inter alia linked to a mechanical failure of Daphnia magna filtration apparatus. Concentrations of 0.01 and 0.10 g/l did not affect crustacean survival and fertility. Shungite in the centration of 0.01 g/l lowered toxic effect of potassium in concentrations of 0.005-0.02 g/l on both Ceriodaphnia and Daphnia magna.

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Phai, Nguyen Van, John Knodel, Mai Van Cam e Hoang Xuyen. "Fertility and Family Planning in Vietnam: Evidence from the 1994 Inter- censal Demographic Survey". Studies in Family Planning 27, n. 1 (gennaio 1996): 1. http://dx.doi.org/10.2307/2138073.

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28

Korzune, Maciel, Fabrício William Ávila, Renato Vasconcelos Botelho, Marcelo Marques Lopes Muller, Poliana Horst Petranski, Eduardo Luiz Costa Tobias Pinto, Talia Aksenen, Sidnei Osmar Jadoski e Leandro Rampim. "Effects of gypsum on growth and nutrient status of forage grasses cultivated between the rows of organically grown Satsuma mandarin in an Oxisol from subtropical Brazil". Crop and Pasture Science 72, n. 11 (2021): 899. http://dx.doi.org/10.1071/cp21316.

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Abstract (sommario):

Gypsum (CaSO4.2H2O) decreases the harmful effect of soil acidity on plants and provides calcium (Ca) and sulfur (S) for plant nutrition. Setaria grass (Setaria anceps Stapf) and black oat (Avena strigosa Schreb.) are forage grasses that are tolerant of low soil fertility and may be suitable as inter-row crops for Satsuma mandarin (Citrus unshiu Marc.) grown organically on Oxisol soils, which may suffer low native fertility and high acidity. We evaluated the effect of gypsum application to a low fertility soil from subtropical Brazil on soil chemical fertility, growth and plant nutrition of Satsuma mandarin, and plant biomass yield and soil nutrient extraction of setaria grass and black oat cultivated between the orchard rows, in the absence of soluble industrial (NPK) fertilisers. The entire experimental field was limed, and ground natural phosphate rock was applied. During planting of the Satsuma mandarin, organic manure and ground natural phosphate rock were mixed with soil and placed in each planting hole. Two agricultural gypsum treatments were applied: one without gypsum (control), and the other with gypsum at 6 tha−1. After 12months, gypsum reduced the level of aluminium (Al3+) and increased Ca2+ at soil depth 0–40cm, and increased S-SO42− at soil depth 0–60cm. Other soil chemical components (pH, phosphorus, potassium, magnesium and micronutrients) were not affected by gypsum application. Gypsum did not affect growth of Satsuma mandarin, but increased leaf S concentration. Between the rows, gypsum decreased nitrogen extraction by setaria grass and increased Ca and S extractions by black oat. Biomass yield and nutrient extraction by the studied forage grasses were satisfactory, considering the poor soil fertility conditions. Setaria grass exhibited higher efficiency in recycling nutrients from the chemically poor soils than black oat. In general, setaria grass and black oat can be used as inter-row forage grasses for organic orchards of Satsuma mandarin, where there are restrictions on use of soluble industrial fertilisers.

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Nomes, Eli, André Grow e Jan Van Bavel. "The Mid-Twentieth Century Baby Boom and the Role of Social Influence. An Agent-Based Modelling Approach". Historical Life Course Studies 8 (18 aprile 2019): 1–26. http://dx.doi.org/10.51964/hlcs9309.

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Around the middle of the 20th century, most Western countries experienced a surge in birth rates, called the Baby Boom. This boom was unexpected at the time and the underlying mechanisms are still not entirely clear. It was characterized by high levels of inter- and intra-country variability in fertility, as some regions even experienced fertility decline during the Boom. In this paper, we suggest that social influence processes, propelling a shift towards two-child families, might have played an important role in the observed changes in fertility. Interactions in social networks can lead new types of childbearing behaviour to diffuse widely and thereby induce changes in fertility at the macro level. The emergence and diffusion of a two-child norm resulted in homogenization of fertility behaviour across regions. Overall, this led to a reduction of childlessness and thus an increase of fertility, as more people aspired to have at least two children. Yet, in those regions where larger family sizes were still common, the two-child norm contributed to a fertility decline. To explore the role of social influence with analytical rigor, we make use of agent-based computational modelling. We explicate the underlying behavioural assumptions in a formal model and assess their implications by submitting this model to computational simulation experiments. We use Belgium as a case study, since it exhibited large variability in fertility in a relatively small population during the Baby Boom years. We use census data to generate realistic starting conditions and to empirically validate the outcomes that our model generates. Our results show that the proposed mechanism could explain an important part of the variability of fertility trends during the Baby Boom era.

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30

Lee, Seung Young, Zhuo Jin, Su Jang, Backki Kim, Jeonghwan Seo e Hee-Jong Koh. "Histological characterization of anther structure in Tetep-cytoplasmic male sterility and fine mapping of restorer-of-fertility gene in rice". PLOS ONE 17, n. 8 (18 agosto 2022): e0268174. http://dx.doi.org/10.1371/journal.pone.0268174.

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Abstract (sommario):

Cytoplasmic male sterility (CMS) is a maternally inherited trait that inhibits plants from producing or releasing viable pollen. CMS is caused by mitochondrial–nuclear interaction, and can be rescued by introducing functional nuclear restorer-of-fertility (Rf) gene. The Tetep-CMS/Rf lines were developed through successive inter-subspecific backcrosses between indica and japonica rice accessions. Phenotypic characterization of Tetep-CMS lines revealed abnormal anther dehiscence and the inability to release, while possessing functional pollen. Transverse sections of developing anthers collected from CMS plants showed connective tissue deformities and aberrant dehydration of endothecium and epidermis. Fine mapping of Rf-Tetep using a series of segregating populations, delimited the candidate region to an approximately 109 kb genomic interval between M2099 and FM07 flanking markers. Nanopore long-read sequencing and genome assembly, proceeded by gene prediction and annotation revealed 11 open reading frames (ORFs) within the candidate region, and suggest ORF6 annotated as pentatricopeptide repeat motif containing gene 1 (PPR1), as a possible candidate gene responsible for fertility restoration. This study suggests that tissue-specific abnormalities in anthers are responsible for indehiscence-based sterility, and propose that the functional Rf gene is derived from allelic variation between inter-subspecies in rice.

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31

Bhattacharyya, Siddhartha Shankar, e Karolina Furtak. "Soil–Plant–Microbe Interactions Determine Soil Biological Fertility by Altering Rhizospheric Nutrient Cycling and Biocrust Formation". Sustainability 15, n. 1 (29 dicembre 2022): 625. http://dx.doi.org/10.3390/su15010625.

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Abstract (sommario):

Understanding soil–plant–microbe inter- and intra- interactions are essential for ensuring proper soil health, quality, and soil-mediated ecosystem services (e.g., nutrient cycling) required for human–plant–animal life. Intensive and unsustainable farming practices can decrease soil microbial biodiversity, fertility, and quality leading to soil degradation, impaired nutrient cycling, and the incapability of soil to support plant growth. Under such a context, soil biological fertility can appear as a regenerative component that has the potential to harmonize and improve soil’s physical, chemical, and biological parameters. This study defines and discusses the microbiome in the rhizosphere, microbial nutrient cycling, and biological soil crusts as the major components of soil biological fertility, and explores the answers to the following questions: (i) how does the rhizosphere promote plant growth, development, and nutrient cycling through soil microorganisms (e.g., bacteria, fungi)? (ii) How can soil microorganisms regulate macronutrient cycling and facilitate biocrust formation? This review reveals that soil biological fertility is crucial for increasing crop resilience and productivity as well as sustainability in agriculture. Additionally, the reintroduction of plant growth promoting rhizobacteria, a quantitative estimation of the root exudate’s composition, identifying the spatiotemporal dynamics of potassium solubilizing bacteria and establishing biological soil crusts in agricultural lands remain the major tasks for improving soil biological fertility and the transition towards regenerative agriculture.

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32

Gomendio, Montserrat, Aurelio F. Malo, Julian Garde e Eduardo R. S. Roldan. "Sperm traits and male fertility in natural populations". Reproduction 134, n. 1 (luglio 2007): 19–29. http://dx.doi.org/10.1530/rep-07-0143.

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Abstract (sommario):

Male fertility has seldom been studied in natural populations because it has been assumed that strong selection would result in uniformly high values among males, and therefore mating success has been equated with fertilisation success. In contrast, male fertility has received much attention in studies of domestic livestock, where economic benefits rely on improving productivity, and in human infertility studies, where the efficiency of treatments depends on understanding which ejaculate traits explain reproductive failures and predict success at assisted conception. Despite years of efforts, no conclusive results have been obtained, probably because such studies have focused on opposite extremes of the range with little variation: domestic livestock have often been subject to strong artificial selection for high fertility, and human patients requiring treatment have compromised fertility. Recent findings from natural populations of red deer have shown that males differ markedly in their fertility, and have revealed the degree of variation found in different semen traits, both between and within males. Fertility trials have shown that male fertility is determined mainly by sperm swimming speed and the proportion of normal sperm, when sperm numbers are kept constant. Sperm design exerts a strong influence on sperm swimming speed, with faster swimming sperm having elongated heads, shorter midpieces and a longer principal plus terminal pieces in relation to total flagellum length. Thus, the large inter-male variation in sperm design found among natural populations underlies differences in sperm swimming speed which, in turn, determine differences in male fertility rates. Secondary sexual characters are honest indicators of male fertility, so males with large and elaborated antlers have larger testes and faster swimming sperm. Testosterone does not seem to mediate the relationship between antler size and semen quality, since it is associated with sperm production, but not with sperm quality or antler size. Finally, more fertile males produce a greater proportion of sons, who will inherit the semen traits which will enhance their fertility.

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Fürstenberg, Henrike. "Voice and Fertility, (Self‐)Impregnation and (Inter‐)Dependence: The Pseudonyms and their (Narratives about) Wives". Kierkegaard Studies Yearbook 27, n. 1 (14 luglio 2022): 73–93. http://dx.doi.org/10.1515/kierke-2022-0005.

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Abstract (sommario):

Abstract By analyzing prefaces and other short excerpts written by different pseudonyms (Nicolaus Notabene, Hilarius Bookbinder, Frater Taciturnus, Judge William and, in contrast, Johannes the Seducer), this paper explores the pseudonymous authors’ relation to their spouses. It assumes that recurring motifs in the prefaces, such as ‘voice’ and the metaphor of ‘fertility,’ reveal, often in ironic tones, general gender-related aspects of identity in Kierkegaard’s works. The paper thus explores how the seemingly stereotyped and archaic conception of gender in the prefaces, such as the pseudonymous author’s assertion of superiority of (male) reasoning through writing over the (female) immediacy represented in voice, reflect aspects of the individual’s disposition before God.

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34

Niazi, I. A. K., S. Rauf, J. A. Teixeira da Silva, Z. Iqbal e H. Munir. "Induced polyploidy in inter-subspecific maize hybrids to reduce heterosis breakdown and restore reproductive fertility". Grass and Forage Science 70, n. 4 (11 settembre 2014): 682–94. http://dx.doi.org/10.1111/gfs.12142.

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35

Chin, Joong Hyoun, Sang-Ho Chu, Wenzhu Jiang, Young-Il Cho, Reflinur Basyirin, Darshan S. Brar e Hee-Jong Koh. "Identification of QTLs for hybrid fertility in inter-subspecific crosses of rice (Oryza sativa L.)". Genes & Genomics 33, n. 1 (febbraio 2011): 39–48. http://dx.doi.org/10.1007/s13258-010-0100-z.

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36

Manrique, Edwin, Verónica Rincón e Humberto Ossa. "Lymphotherapy induce an increase of blocking factors and correct infertility problems". Nova 11, n. 19 (15 giugno 2013): 25. http://dx.doi.org/10.22490/24629448.1020.

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Abstract (sommario):

This study aimed to confirm the presence of Blocking Factors (BFs) in Mixed Lymphocyte Culture (MLC) from female normal reproducer and sub-fertile rabbit inoculated with two injection of the allogenic lymphotherapy (LIT) to analyze its effect on rate fertility and pregnancy success. The BFs measuring was done intervening MLC with MTT-Formazan non-radioactive technique. It was demonstrated BFs presence in MLC in female rabbit groups.. In sub-fertile female reproducers treated with allogenic lymphotherapy a significant increase in the level of FBs after every LIT was observed, as well as a rate fertility increase.. Furthermore, it was established that BFs act on cell proliferation inhibiting the MLC of other species, clearly indicating that the inhibit effect of the BFs is inter-specific and no intraspecific as had sustain until now.

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37

GIPSON, JESSICA D., e MICHELLE J. HINDIN. "INTER-GENERATIONAL RELATIONSHIPS BETWEEN WOMEN'S FERTILITY, ASPIRATIONS FOR THEIR CHILDREN'S EDUCATION AND SCHOOL COMPLETION IN THE PHILIPPINES". Journal of Biosocial Science 47, n. 06 (9 dicembre 2014): 825–44. http://dx.doi.org/10.1017/s0021932014000510.

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Abstract (sommario):

SummaryWomen's education is associated with positive social and health outcomes for women and their families, as well as greater opportunities and decision-making power for women. An extensive literature documents ways in which broader, societal changes have facilitated roles for women beyond reproduction, yet there is minimal exploration at the family level. This study used inter-generational cohort data from the Philippines to examine mothers' aspirations for their children's education, and how these aspirations predict children's subsequent educational attainment. Mothers' education, household wealth and a locally developed measure of women's status were positively associated with higher educational aspirations for children; however, only mothers with the highest fertility were less likely to desire their children to attend college or higher. Mothers' fertility and aspirations both significantly and independently predicted children's school completion. Together, these findings indicate that increased opportunities for Filipina women beyond childbearing may not only positively benefit these women themselves, but also future generations.

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38

Ahmed, A., S. G. Shaon, M. S. Islam, P. S. Saha e M. M. Islam. "GENETIC DIVERGENCE ANALYSIS IN HRDC RICE (Oryza sativa L.) HYBRIDS IN BANGLADESH". Bangladesh Journal of Plant Breeding and Genetics 27, n. 2 (24 maggio 2016): 25–32. http://dx.doi.org/10.3329/bjpbg.v27i2.27842.

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Abstract (sommario):

Genetic divergence of 48 IRRI developed F1 rice hybrids were studied through Mahalanobis D2 and principal component analysis for ten characters in Gazipur and Pabna district during dry season 2012-13. Among 48 genotypes, cluster analysis resulted in five clusters following Wards method. During dry season for both regions, cluster I incorporated the highest number of genotypes. Significant differences among the genotypes but non-significant differences among replications were noticed for most of the parameters under study. The inter-cluster distance was larger than intra-cluster distance suggesting wider diversity among the genotypes. In Gazipur, the maximum inter-cluster D2 value was recorded between cluster III and V (6.69) and the minimum between cluster II and IV (0.69). The intra-cluster distance was maximum in cluster IV (3.60) and minimum in cluster I (0.33). In Pabna, maximum inter-cluster distance was exhibited between cluster IV and II (16.43) but minimum between cluster II and III (3.98). Maximum intra-cluster distance (4.40) was recorded in cluster IV whereas minimum in cluster I (0.83). Based on positive value of vector 1 and vector 2, panicle number m-2, spikelet fertility (%) and 1000-grain wt. (g) had maximum contribution towards genetic divergence among the characters studied. Cluster means indicated considerable differences in the mean values of different parameters. The highest cluster means for panicle weight (g), spikelet fertility (%), 1000 grain wt. (g) and grain yield (kg ha-1) were derived from cluster IV. Therefore, more prominence should be given to the lines under cluster IV that having genetic potentiality to contribute better for yield maximization of hybrid rice.

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39

Meidutė-Kavaliauskienė, Ieva, Gitana Dudzevičiūtė e Nijolė Maknickienė. "MILITARY AND DEMOGRAPHIC INTER-LINKAGES IN THE CONTEXT OF THE LITHUANIAN SUSTAINABILITY". Journal of Business Economics and Management 21, n. 6 (29 settembre 2020): 1508–24. http://dx.doi.org/10.3846/jbem.2020.13444.

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This paper aims at investigating military and demographic inter-linkages in the context of the Lithuanian sustainability. The investigation combines three important economic aspects such as demographic, military and sustainable development. The authors have revealed that demographic trends should be seen as a necessary conditions for ensuring the functioning of the military sector contributes to public security and sustainable development in general. Correlation and stepwise regression analysis, also Monte Carlo forecasting method have been applied for this purpose. Research results have revealed statistically significant interrelationship between military personnel as a share of total labour force and population growth rate, population median age, total fertility rate as well as birth rate. Moreover, Monte Carlo forecasting method allowed revealing for the next 10 years a steady slight increase in armed forces personnel, stable population growth rates, a rapid aging process and a slight decline of total fertility rate. Military and demographic estimations and future projections allow government to incorporate information into planning and sustainable development policy. The insights from this research may contribute to implementing the goals of sustainable development related to eradication of poverty, inequality, social exclusion, improvement in education, well-being and employment and tackling climate change.

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40

Chandrasekaran, Murugesan, Manivannan Paramasivan e Jesudass Joseph Sahayarayan. "Microbial Volatile Organic Compounds: An Alternative for Chemical Fertilizers in Sustainable Agriculture Development". Microorganisms 11, n. 1 (22 dicembre 2022): 42. http://dx.doi.org/10.3390/microorganisms11010042.

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Abstract (sommario):

Microorganisms are exceptional at producing several volatile substances called microbial volatile organic compounds (mVOCs). The mVOCs allow the microorganism to communicate with other organisms via both inter and intracellular signaling pathways. Recent investigation has revealed that mVOCs are chemically very diverse and play vital roles in plant interactions and microbial communication. The mVOCs can also modify the plant’s physiological and hormonal pathways to augment plant growth and production. Moreover, mVOCs have been affirmed for effective alleviation of stresses, and also act as an elicitor of plant immunity. Thus, mVOCs act as an effective alternative to various chemical fertilizers and pesticides. The present review summarizes the recent findings about mVOCs and their roles in inter and intra-kingdoms interactions. Prospects for improving soil fertility, food safety, and security are affirmed for mVOCs application for sustainable agriculture.

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41

McLachlan, R. I., C. Mallidis, K. Ma, S. Bhasin e D. M. de Kretser. "Genetic disorders and spermatogenesis". Reproduction, Fertility and Development 10, n. 1 (1998): 97. http://dx.doi.org/10.1071/r98029.

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Abstract (sommario):

Male infertility affects one man in twenty and a genetic basis seems likely in at least 30% of those men. Genetic regulation of fertility involves the inter-related processes of testicular development, spermatogenesis (involving germ cell mitosis, meiosis and spermatid maturation), and their endocrine and paracrine regulation. In regard to spermatogenesis, particular attention has been given to the Yq11 region, where some spermatogenesis genes (‘azoospermia factors’) appear to be located. Several candidate genes have been identified but have not been shown to have a defined or essential role in spermatogenesis. Microdeletions of Yq11 are found in ~15% of azoospermic or severely oligospermic men. The complexity of the genetic control of male fertility is demonstrated by the evidence for genes involved in spermatogenesis and sexual differentiation on the X chromosome and autosomes. Better understanding of the genetic regulation of normal spermatogenesis will provide new probes for clinical studies; however, at present the majority of spermatogenic failure remains without an identified genetic linkage. The advent of intracytoplasmic sperm injection permits fertility in many previously sterile men and presents the possibility of their transmission of infertility; appropriate counselling is required.

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42

Majumder, Ratna Rani, Ripon Kumar Roy, MA Khaleque Mian e Nasrin Akter Ivy. "Genetic divergence of aromatic rice (Oryza sativa L.)". Bangladesh Journal of Botany 44, n. 2 (13 ottobre 2018): 185–91. http://dx.doi.org/10.3329/bjb.v44i2.38506.

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Abstract (sommario):

Thirty aromatic rice genotypes were studied to assess the nature and magnitude of genetic divergence among them for grain yield and yield contributing characters. Based on 23 characters the genotypes were grouped into 5 clusters. Inter-distances were higher than intra-cluster showing a wide range of genetic diversity among the genotypes of different groups. The highest level of inter-cluster distance (73.48) was found between cluster IV and V. The highest intra-cluster distance (3.364) was computed to cluster V and the lowest 1.851 was observed in cluster IV. Panicle length, days to initial flower opening, spikelet sterility, pollen fertility and harvest index had maximum contribution towards genetic divergence of 30 aromatic rice genotypes. Genotypes having these characters in the genetically distant cluster could, therefore, offer a significant scope for the development of high yielding variety through judicious selection.

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Akagi, Hiromori, Yumi Yokozeki, Akiko Inagaki, Atsushi Nakamura e Tatsuhito Fujimura. "A codominant DNA marker closely linked to the rice nuclear restorer gene, Rf-1, identified with inter-SSR fingerprinting". Genome 39, n. 6 (1 dicembre 1996): 1205–9. http://dx.doi.org/10.1139/g96-152.

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Abstract (sommario):

A new molecular marker (OSRRf) closely linked to the nuclear restorer gene (Rf-1) for fertility in rice has been found. The Rf-1 gene is essential for hybrid rice seed production. A PCR-fingerprinting technique using simple sequence repeats (SSRs) was applied to compare two near-isogenic lines with (MTC-10R) or without (MTC-10A) the Rf-1 gene. Of 76 inter-SSR primers tested, only one primer, (AG)8YC, generated polymorphisms. The tetranucleotide repeats generating polymorphisms were found within each amplicon. The genetic distance between OSRRf and Rf-1 was 3.7 ± 1.1 cM. As in the case of a codominant marker, this marker will be applied not only to breeding both restorer lines and maintainer lines, but also to the purity management of hybrid rice seeds. Key words : Oryza sativa L., restorer gene Rf-1, microsatellite, inter-repeat fingerprinting.

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44

M Coşkun, Anahit, Nebahat Özerdoğan, Eylem Karakaya e Eda Yakıt. "Fertility characteristics and related factors impacting on Syrian refugee women living in Istanbul". African Health Sciences 20, n. 2 (22 luglio 2020): 682–89. http://dx.doi.org/10.4314/ahs.v20i2.19.

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Abstract (sommario):

Background: Women’s fertility characteristics are affected by many different factors. Aim: To gain an awareness of fertility characteristics of Syrian refugee women and the influential factors. Methods: This study was planned as a cross-sectional study to determine the efficiency and related factors of Syrian refugees living in Istanbul. The survey of 300 refugee women applying Arabs who migrated to Turkey, Kurds, Turkmen and Yezidi origin they receive. Results: Average age of the women studied was 34.26 ± 10.15, 34.6% of the participants had not received any education, 37% had less than two-year inter-pregnancy interval, 58.6% have not received “Safe Motherhood” service, 43.6% have conceived their last child unwillingly. Women in the study group had in average 3±2,4 children and the number of children they wanted was 3±1,59. These values were substantially affected negatively by the women’s education level and positively by the income level. Yezidis had significantly more children than other ethnic groups and did not have a “religious ban” on voluntary abortion. Conclusion: It has been noted that fertility characteristics of refugee women who migrated to Turkey changed according to their ethnic backgrounds and were sustained in the country they migrated to. Along with harsh living conditions and insufficient access to health services the situation has been observed to pose serious risks on reproductive health. Keywords: Syrian refugee woman; fertility characteristics; impacting factors.

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45

Lamb, B. C., Z. Kozlakidis e M. Saleem. "Inter-strain cross-fertility tests on cultures from Israel and America in the homothallic fungus, Sordaria fimicola". Fungal Genetics Reports 47, n. 1 (25 luglio 2000): 69–71. http://dx.doi.org/10.4148/1941-4765.1206.

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46

Reques Velasco, Pedro, e Vicente Rodriguez Rodriguez. "The seven demographic Spains. Inter-municipal contrasts in age structure : fertility and migration are the determining factors". Espace, populations, sociétés 18, n. 3 (2000): 425–35. http://dx.doi.org/10.3406/espos.2000.1962.

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47

Li, Xuehui, e E. Charles Brummer. "Inbreeding Depression for Fertility and Biomass in Advanced Generations of Inter- and Intrasubspecific Hybrids of Tetraploid Alfalfa". Crop Science 49, n. 1 (gennaio 2009): 13–19. http://dx.doi.org/10.2135/cropsci2008.04.0205.

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48

Mozhar, Nina. "Phenotypic assessment of pear varieties in mutual pollination". BIO Web of Conferences 34 (2021): 01012. http://dx.doi.org/10.1051/bioconf/20213401012.

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Abstract (sommario):

The self-fertility and cross-fertility of pear varieties have been studied in the conditions of the of the Krasnodar region. It was established that most of the not varieties are self-fertile. The varieties are distinguished: Ladozhskaya, Malyshka and Talgar beauty, with partial self-fertility, in which a low percentage of fruit set and its fluctuation over the years are noted. Based on the pollination performed and the analysis carried out, good and acceptable pollinators for promising pear varieties were selected. It has been established that in order to form full-fledged seeds in the fruit of the pear, a full cross-pollination with good pollinators is necessary. The possibilities of individual varieties (a high percentage of fruit tying) with mutual pollination are presented. The analysis of the negative influence of technogenic factors during flowering on the inter-pollination of varieties has been carried out. Cross-pollinated varieties have a narrow selective ability to pollinate varieties, which varies over the years and depends on the growing conditions. Proved the need, when laying gardens correctly choose varieties-pollinators in order to increase the yield of varieties. According to the research results, a self-fertile variety Iyulskaya early was identified. The best pollinators were selected for promising pear varieties for the conditions of the Kuban.

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Parwata, I. Gusti Made Arya, I. Komang Damar Jaya, Bambang Budi Santoso e Jayaputra Jayaputra. "Kajian Aplikasi Pupuk Organik Pada Tumpang Sari Tanaman Kelor-Selada Di Lahan Kering". JURNAL SAINS TEKNOLOGI & LINGKUNGAN 5, n. 1 (26 giugno 2019): 42. http://dx.doi.org/10.29303/jstl.v5i1.105.

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Lettuce and Moringa are recently popular vegetable crops because their demand improves significantly, and their development lead to dry land because its potencial in Indonesia is still high. The use of dry land should be followed by applying inter cropping technique in order to make plant micro climate becomes more favourable. In addition, low soil fertility and intensive ussage of inorganic fertilizers makes the application of organic fertilizers imperative. The objective of the research is to investigate the type of organic fertilizer giving high yield of lettuce and moringa cultivated using inter cropping technique in dry land. The results showed that the organic fertilizers applied improved the plant growth and yield, and also improved the land equivalent ratio (LER). The highest LER was showed by apllication of Organox, followed by Bio Extrim and Biota Plus, and the lowest one showed by without organic fertilizer application.

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Huchard, Elise, Alexandre Courtiol, Julio A. Benavides, Leslie A. Knapp, Michel Raymond e Guy Cowlishaw. "Can fertility signals lead to quality signals? Insights from the evolution of primate sexual swellings". Proceedings of the Royal Society B: Biological Sciences 276, n. 1663 (25 febbraio 2009): 1889–97. http://dx.doi.org/10.1098/rspb.2008.1923.

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The sexual swellings of female primates have generated a great deal of interest in evolutionary biology. Two hypotheses recently proposed to elucidate their functional significance argue that maximal swelling size advertises either female fertility within a cycle or female quality across cycles. Published evidence favours the first hypothesis, and further indicates that larger swellings advertise higher fertility between cycles. If so, a male preference for large swellings might evolve, driving females to use swellings as quality indicators, as proposed by the second hypothesis. In this paper, we explore this possibility using a combination of empirical field data and mathematical modelling. We first test and find support for three key predictions of the female-quality hypothesis in wild chacma baboons ( Papio ursinus ): (i) inter-individual differences in swelling size are maintained across consecutive cycles, (ii) females in better condition have larger swellings and higher reproductive success, and (iii) males preferentially choose females with large swellings. We then develop an individual-based simulation model that indicates that females producing larger swellings can achieve higher mating success even when female–female competition is low and within-female variance in the trait is high. Taken together, our findings show that once sexual swellings have evolved as fertility signals, they might, in certain socio-sexual systems, be further selected to act as quality signals. These results, by reconciling two hypotheses, help to clarify the processes underlying sexual swelling evolution. More generally, our findings suggest that mate choice for direct benefits (fertility) can lead to indirect benefits (good genes).

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