scholarly journals The Fertility of Immigrants From Low-Fertility Settings: Adaptation in the Quantum and Tempo of Childbearing?

Demography ◽  
2021 ◽  
Author(s):  
Eleonora Mussino ◽  
Ben Wilson ◽  
Gunnar Andersson
Keyword(s):  
Working Life ◽  
Children Of Immigrants ◽  
Migration Background ◽  
Low Fertility ◽  
High Fertility ◽  
Welfare Regime ◽  
Birth Timing ◽  
Straight Line ◽  
Fertility Differentials ◽  
Low Levels

Abstract Immigrant women who have lived longer in a destination often have relatively low levels of fertility, which is sometimes taken as evidence of the adaptation of behavior. This evidence is almost exclusively based on studies of immigrants from high-fertility settings, while the fertility of immigrants from low-fertility settings has been largely overlooked. Research has also rarely studied the fertility of immigrants who migrated as children, despite the methodological advantages of applying such an approach. This study focuses on women who grew up in Sweden with a migration background from low-fertility origins. We expect that Sweden's welfare regime makes it easier for women to combine childbearing and working life, regardless of migration background, thereby facilitating an adaptation of fertility behavior toward that prevailing in Sweden. We find evidence of adaptation in terms of birth timing for at least half of the country-origin groups that we study, but very little evidence of adaptation in terms of completed fertility. Further, we find that, in comparison with ancestral Swedes, completed fertility differentials are larger for second-generation individuals than for immigrants who arrived during childhood. This is evidence against the notion of “straight-line” adaptation for immigrants and the children of immigrants who are born in Sweden.

Effects of CO2 in interaction with temperature and soil fertility on the foliar phenology of alder, birch, and maple seedlings

1995 ◽  
Vol 73 (2) ◽  
pp. 149-157 ◽  
Author(s):  
Takayoshi Koike
Keyword(s):  
Low Fertility ◽  
High Fertility ◽  
Betula Platyphylla ◽  
Leaf Production ◽  
Bud Formation ◽  
Alnus Hirsuta ◽  
Low Levels ◽  
Sympodial Growth ◽  
Acer Mono ◽  
Foliar Phenology

The foliar phenology of potted 1-year-old seedlings of alder (Alnus hirsuta Turcz.), maple (Acer mono Maxim.), and birch (Betula platyphylla Sukatch. var. japonica Hara) was observed from May to September in eight growth environments: factorial combinations of temperatures (light:dark, 30:20 °C and 26:16 °C), CO2 level (70 and 36 Pa), and nutrient regime (high versus low levels of fertilization). Seedlings grown at high fertility always had more leaves, and under high CO2, shed leaves slightly later than seedlings grown at low fertility. Except for maple, production of newly formed shoots and leaves was accelerated by high CO2. In maple, high CO2 only increased the number of flushes of the leader shoot. Alder and birch accelerated sylleptic shoot and leaf production at high CO2 in fertile conditions. The production of new leaves by alder grown at high CO2 and low fertility was almost the same as that grown under normal CO2, at high fertility. At high CO2, the timing of winter bud formation of monopodial alder and maple was delayed, while that of sympodial birch was almost the same as at ambient CO2. Key words: foliar phenology, elevated atmospheric CO2 and temperature, monopodial versus sympodial growth, nutrient levels, winter bud formation, global change.

Comparative responses of Lolium perenne and Bothriochloa macra to temperature, moisture, fertility and defoliation

1976 ◽  
Vol 27 (6) ◽  
pp. 769 ◽  
Author(s):  
SJ Cook ◽  
A Lazenby ◽  
GJ Blair
Keyword(s):  
Lolium Perenne ◽  
Competitive Ability ◽  
New South ◽  
Moisture Stress ◽  
Low Fertility ◽  
High Fertility ◽  
South Wales ◽  
Temperature Regimes ◽  
Low Levels ◽  
Moisture Conditions

Lolium perenne and Bothtriochloa macra were grown alone and In 1/1 mixtures In pot culture under molsture stress and moisture non-limiting conditions at both high and low levels of fertility, they were grown In three controlled environment cabinets operating at either 16/10°, 23/17° or 31/25°C, and defoliated to either 1 cm or 4 cm from the crown at each of two harvests.Temperature was the dormant factor differentiating the growth and competitive ability of both species Lolium grew best In the 16/10° and 23/17°C temperature regimes, production declining at 31/25° In contrast, Bothriochloa made very little growth a1 16/10° and responded linearly to measuring temperature. Both species responded similarly to increasing fertility and favourable moisture conditions, although such treatments had no effect on Bothriocochloa in the 16/10°C temperature regime Bothtriochloa was more tolerant of low fertility and moisture stress than was Loliurn, especially at 31/25° Lolium yielded more, and competed successfully with Bothtriochloa, only under conditions of high fertility and In the absence of moisture stress at temperatures up to 23/17°C Defoliation intensity had little effect on the total dry matter yields of either species, although it did influence the proportion of leaf to head and stem of Bothtriochloa. The likely implications of the results on the competitive relationships of the two species In the field In the Northern Tablelands environment of New South Wales are discussed

ON-FARM FORESTRY DEVELOPMENT OPTIONS FOR NORTHLAND

1986 ◽  
pp. 27-32
Author(s):  
J.S. Clark
Keyword(s):  
Joint Ventures ◽  
Low Fertility ◽  
High Fertility ◽  
Financial Returns ◽  
Farm Forestry ◽  
Hill Country ◽  
Financial Position ◽  
On Farm

Agroforests and woodlots offer Northland hill country farmers investment and diversification opportunities. Agroforests have less effect on the "whole farm" financial position than woodlots, especially where a progressive planting regime is adopted and where no further borrowing is required. Establishment and tending costs for agro-forests are lower, and returns come much sooner. The proven opportunity for continued grazing under trees established in this manner, apart from a short post-planting period, further enhances the agroforesty option. Even where there is reluctance on a farmer's part to plant trees on high fertility land, the expected financial returns from agroforests on low and medium fertility land will increase the overall long-term profitability and flexibility of the whole farming operation. Woodlots may be more appropriate on low fertility areas where weed reversion is likely. Joint ventures may be worth considering where farm finances are a limited factor. Keywords: On-farm forestry development, Northland hill country, agroforestry, woodlots, diversification, joint ventures, progressive planting regimes, grazing availability.

Comparing infertility-related stress in high fertility and low fertility countries

2021 ◽  
pp. 100653
Author(s):  
Emily A. Groene ◽  
Cyrialis Mutabuzi ◽  
Dickson Chinunje ◽  
Ester Matson Shango ◽  
Shalini Kulasingam ◽  
...  
Keyword(s):  
Low Fertility ◽  
High Fertility ◽  
Related Stress

scholarly journals SUATU PENDEKATAN ANALISIS MULTIVARIAT TENTANG TINGKAT KELAHIRAN PADA BEBERAPA KELOMPOK DAN ETNIS WANITA PERNAH KAWIN DI IRIAN JAYA

Populasi ◽  
2016 ◽  
Vol 3 (1) ◽  
Author(s):  
Pieter J. Soumokil
Keyword(s):  
Rural Women ◽  
Rural Areas ◽  
Urban Women ◽  
Developed Countries ◽  
Low Fertility ◽  
Dominant Factor ◽  
High Fertility ◽  
Irian Jaya ◽  
Lower Fertility

It has been argued by many demographers that socio economic development with its associated fundamental changes in the role of women and the value of children is the dominant factor in the transition from high to low fertility. Research in less developed countries has found lower fertility levels in urban population compared to rural population. It was therefore assumed that the modernizing role of urbanlife helped bring about a decline infertility levels.This study in Irian Jaya, however, convincingly shows that fertility of urban women in Irian Jaya is higher than that of rural women. This differential infertility in favour of urban women in Irian Jaya appears to be real and not a result of underreporting of total live births in rural areas.The reasons for lower fertility in the rural areas in IrianJaya remain unknown, and more research is therefore needed. However, this study strongly suggests that the traditional system of swidden agricultyure in Irian Jaya, which places a highvalue on the labour input of women, may play a major role in constraining fertility in rural area of this province. On the other hand, high fertility in urban areas takes place because urbanwomen have their first birth earlier thanwomen inthe rural areas.

Decomposing the Effect of Women Educational Status on Fertility Across the Six Geo-political Zones in Nigeria: 2003-2018

2020 ◽  
Author(s):  
Tubosun Alex Olowolafe
Keyword(s):  
Educational Status ◽  
Fertility Rate ◽  
Reproductive Age ◽  
High Fertility ◽  
Age At First Birth ◽  
Fertility Level ◽  
Cross Sectional ◽  
North East ◽  
Fertility Variation ◽  
Fertility Differentials

Abstract Background: High level of fertility has been consistently reported in Nigeria. Women education is often identified as one of the important factors that have contributed to reduction in fertility across countries. It is essential to identify the factors that explain the fertility variation in educational status and know the extent of association of these factors across the regions in Nigeria. Thus, this study aimed to examine the fertility differentials among uneducated and educated women in Nigeria.Methods: A cross-sectional population-based design which involved secondary data analyses of the weighted sample of 2003 (n1=7620), 2008 (n2=33385), 2013 (n3=38948) and 2018 (n4=41821) Nigeria Demographic and Health Survey data sets was used. Fertility was measured from information on the full births history of women aged 15-49 years. Oaxaca-Blinder decomposition was used to identify factors that explain fertility differentials among educated and not educate women (α=0.05).Result: Total fertility rate estimate was higher among uneducated women (6.7) than educated women (4.5) in 2018. The pattern was similar across the regions and survey periods. The mean children ever born among women aged 45-49 years was significantly higher among the uneducated than educated women in each of the survey year. Maternal age at first marriage, wealth index and age at first birth were contributory factors to the dissimilarities found in fertility between the educated and uneducated women. Risk difference (RD) of high fertility between uneducated-educated women was highest in South-East (RD=56.9; 95%CI=49.1-64.8) and least in North-East (RD=15.0; 95%CI=9.9-20.1).Conclusion: The fertility level in Nigeria was high but more prominent among the uneducated than educated. Improving the level of educational enrolment of women of reproductive age will facilitate reduction in the fertility rate in Nigeria.

The Demographic Footprint of Economic Development

2014 ◽  
Vol 5 (4) ◽  
pp. 67-84
Author(s):  
Vasilis S. Gavalas
Keyword(s):  
Economic Development ◽  
Aegean Sea ◽  
Natural Increase ◽  
Low Fertility ◽  
Population Mobility ◽  
Dynamic Relationship ◽  
Key Factor ◽  
Real Increase ◽  
Low Levels ◽  
The Relationship

This paper examines the dynamic relationship between economic development and the demographics of population for a group of islands in the middle of the Aegean Sea, namely the Cyclades, in the period 1860-2011. This period covers the greatest part of demographic transition, which for the Cyclades started in the mid-nineteenth century. In every stage of the transition, the changes in mortality and fertility levels tended to destabilise the relationship between population and the limited resources of the islands. Migration is the key factor in understanding the demographic regime of these islands. Either negative or positive (emigration or immigration), population mobility has always been and still is the element that regulates natural increase and determines the real increase of the population. Whenever rates of natural increase were too high, emigration acted as a counterbalancing factor by taking population away from the islands, while when rates of natural increase reached very low levels from the 1970s onwards due to low fertility, immigration came as a substitute. Two of the Cyclades islands, namely Paros and Naxos, are used as cases studies for a closer focus on these islands during the 20th and the beginning of the 21st century and especially in the period 1951-2011.

scholarly journals Changes in Bull Semen Metabolome in Relation to Cryopreservation and Fertility

Animals ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 1065
Author(s):  
Valentina Longobardi ◽  
Michal A. Kosior ◽  
Nunzia Pagano ◽  
Gerardo Fatone ◽  
Alessia Staropoli ◽  
...  
Keyword(s):  
Seminal Plasma ◽  
Glycine Betaine ◽  
Low Fertility ◽  
High Fertility ◽  
Over Expression ◽  
Bull Semen ◽  
Before And After ◽  
Associated Proteins ◽  
Cellular Compartments

Semen cryopreservation determines several sperm damages, including the loss of fertility-associated proteins. The purpose of the study was to compare the metabolite contents in bovine sperm and seminal plasma before and after cryopreservation, and between high- and low-fertility bulls in vitro. Forty-eight ejaculates, collected from eight bulls (six per bull), were analyzed by liquid chromatography–mass spectrometry. Cryopreservation resulted in an over-expression of lysophosphatidylcholine (0:0/18:2(9Z,12Z)) in seminal plasma. In addition, higher levels of glycine betaine and pyro-l-glutaminyl-l-glutamine were observed in cryopreserved compared to fresh spermatozoa. The fresh seminal plasma of high-fertility bulls showed an over-expression of l-acetylcarnitine, glycerol tripropanoate, 2,3-diacetoxypropyl stearate and glycerophosphocholine, and an under-expression of lysophosphatidylcholine and butyrylcarnitine, compared to low-fertility bulls. Higher levels of glycerophosphocholine and lysophosphatidylcholine (16:0/0:0) were recorded in fresh spermatozoa from high-fertility bulls. In high-fertility bulls, a greater content of glycerophosphocholine and lower levels of butyrylcarnitine, glycine betaine and l-carnitine were found in cryopreserved seminal plasma, and lower levels of glycine betaine were detected in cryopreserved spermatozoa. In conclusion, cryopreservation affects bovine semen metabolome at both plasmatic and cellular compartments, and metabolic profile differs between high- and low-fertility bulls.

Transcriptome profile and association study revealed STAT3 gene as a potential quality marker of bovine gametes

Zygote ◽  
2020 ◽  
Vol 28 (2) ◽  
pp. 116-130
Author(s):  
Nasser Ghanem ◽  
Dessie Salilew-Wondim ◽  
Michael Hoelker ◽  
Karl Schellander ◽  
Dawit Tesfaye
Keyword(s):  
Estrous Cycle ◽  
Semen Quality ◽  
Sperm Quality ◽  
Expression Patterns ◽  
Cdna Array ◽  
Transcript Abundance ◽  
Low Fertility ◽  
High Fertility ◽  
Nucleotide Polymorphisms ◽  
Genetic Merit

SummaryThe present study was aimed to investigate differences in molecular signatures in oocytes derived from Holstein-Friesian heifers with different genetic merit for fertility, euthanized during day 0 or day 12 of the estrous cycle. Moreover, association between single nucleotide polymorphisms (SNPs) of ODC1 and STAT3 genes and bull fertility traits was investigated. The gene expression patterns were analyzed using cDNA array and validated with quantitative real-time polymerase chain reaction (PCR). The result revealed that several genes have shown not only to be regulated by fertility merit but also by the day of oocyte recovery during the estrous cycle. The STAT3 gene was found to be upregulated in oocytes recovered from animals with high fertility merit at both day 0 and day 12. Some other genes like PTTG1, ODC1 and TUBA1C were downregulated at day 0 and upregulated at day 12 in high, compared with low, fertility merit recovered oocytes. In contrast, the transcript abundance of TPM3 was upregulated at day 0 and downregulated at day 12 in high, compared with low, fertility merit recovered oocytes. In addition, ODC1 and STAT3 were found to be associated (P < 0.05) with sperm quality traits as well as flow cytometry parameters. Therefore, the expression of several candidate genes including ODC1 and STAT3 was related to the genetic merit of the cow. In addition polymorphisms in these two genes were found to be associated with bull semen quality.

scholarly journals Planning a family in Nairobi’s informal settlements: results of a qualitative study

2019 ◽  
Vol 52 (2) ◽  
pp. 286-299 ◽  
Author(s):  
Catriona A. Towriss ◽  
Donatien Beguy ◽  
Alison Wringe ◽  
Barwako Hassan Hussein ◽  
Ian M. Timæus
Keyword(s):  
Family Planning ◽  
Focus Group ◽  
Family Size ◽  
Reproductive Age ◽  
Low Fertility ◽  
Present Moment ◽  
High Fertility ◽  
Focus Group Discussions ◽  
Group Discussions ◽  
Childbearing Intentions

AbstractChildbearing intentions among women in high-fertility contexts are usually classified into those wanting to have a baby, those wanting to ‘space’ a birth and those wanting to ‘limit’ their family size. However, evidence from Africa increasingly suggests that women’s intentions are more complex than this classification suggests, and that there is fluidity in these intentions. This research explores women’s accounts of their childbearing intentions and decisions in order to examine how this fluidity plays out in a low-fertility context in urban Africa. Six focus group discussions were conducted in April and May 2012 with women of reproductive age in Nairobi, Kenya. Participants were recruited using random and purposive sampling techniques. The focus group discussions had an average of seven participants each. Data were coded thematically and analysed using Nvivo software. The analysis explored the factors that women consider to be influential for childbearing and found that the health of the mother and child, costs of raising a child and relationships were commonly reported to be important. Evidence of intentions to space births and limit family size was found. However, the data also showed that there is fluidity in women’s family planning intentions, driven by changes in relationships or household finances, which often result in a desire to avoid pregnancy in the present moment. The fluidity observed in women’s childbearing intentions cannot be accounted for by the concepts of either ‘spacing’ or ‘limitation’ but is best explained by the concept of ‘postponement’. The research reveals the need for family planning clinics to provide a full method mix, as well as high-quality counselling, to enable women to choose a method that best suits their needs.

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