Individual Fertility Research Articles

Salvelinus boganidae lake Sobachie (Putorana plateau): age, growth, demographic parameters

Lake-river char, described as Boganid char, in the lake Sobatchie (Putorana Plateau) is one of the main representatives of the ichthyofauna. There were not any special works examined the char ecological and demographic parameters peculiarities inhabiting this water body. Present day studies are based on small sample sizes. The purpose of this publication is to determine the age, size, and demographic characteristics of the Boganid char in Lake Sobatchie. The paper presents the results of studies of the size-age and demographic parameters of the Boganid char of Lake Sobatchie for 2013-2018 The studies were carried out according to the methods existing in modern ichthyology. The catches included fish aged from 2 to 13 years, females aged 7-10 and males aged 8-11 dominated. The length of the char (SL) ranged from 157 to 620 mm, the mass is from 40 to 4000 g. There was a great variability in growth: the sizes of fish of the same age can differ by 1.5-3.2 times, the weight - by 5-45 times. The sex ratio is 60:40 in favor of females. Sexual maturity occurs at the age of 5 years when females reach length (SL) 307 mm, weight - 348 g; males - 286 mm and 275 g, respectively. The period of puberty is extended to 7 years. The presence of a small part of immature fish in older age groups may indicate that some producers miss their annual spawning. The values of individual fecundity of the Boganid char range from 540-8207 eggs, relative - 0.963.53 eggs. Fertility values functionally depend on the age and size of fish with high coefficients of determination. The fish migration in the lake Sobatchie and its food items information is provided. The conclusion is made that the number of Boganid char in the lake Sobatchie is limited by the capacity of the spawning grounds of the river Horonen. The Boganid char size and age composition research results are presented. Fish aged from 2 to 13 years old were found in the catches, females aged 7-10 and males aged 8-11 years were dominating. Boganid char length reach from 157 up to 620 mm, weight – 40-4000 g. The large variability of growth was noted: the same-aged fish sizes can be varied by 1.5-3.2 times, weight – 5-45 times. The sex ratio is 60:40 in favor of females. Puberty occurs at the age of 5 years when females reach the 307 mm length and 348 g weight; males - 286 mm and 275 g, respectively. The puberty period is stretched up to 7 years. The Boganid char individual fertility value fluctuates from 540 up to 8207 caviar. The fertility values functionally depend on the fish age and size with high determination coefficients. It was concluded that Lake Sobatchie Boganid char population limited by the river Horonen spawning areas capacity.

Effects of different combinations of N, P and K at different time interval on vegetative, reproductive, yield and quality traits of mango (Mangifera Indica. L) cv. Dusehri.

The experiment was carried out on mango cv. Dusehri to investigate the effect of N, P and K fertilizers on vegetative, reproductive growth, yield and fruit quality. Eight different fertilizer combinations such as T1 (control), T2 (N), T3 (P), T4 (K), T5 (NP), T6 (NK), T7 (PK) and T8 (NPK) were used. Individual or combine fertilizer application of N (1000 g), P (750 g) and K (750 g) were applied during growing season in February and August. All the treatments significantly influenced on vegetative growth, flowering, fruiting, yield and other physiochemical attributes of mango as compared to control. Least effect was observed with individual fertilizer application while combine fertilizer treatments enhanced most of the investigated parameters. Especially, qualitative traits showed non-significant differences between treated and untreated mango trees. However, among the different treatments T8 (NPK) showed significance for fruiting aspects such as maximum size of growth flushes (177.51 mm), total number of panicles/tree (845), total number of flowers/panicle (974), sex ratio (69.18%), fruit retention (13.85%), total number of fruits/tree (379), yield (82 kg/tree), fruit weight (197.5 g), pulp weight (135.5 g) and physiochemical parameters namely TSS (24.53), Vit. C (57.63 mg/100 mL) and total sugar (20.84%). In general, combine application of NPK (T8) were the most effective in enhancing fruiting aspects, yield, physiochemical characteristics as well as improved fruit quality of mango trees.

Improvement of Wheat Grain Yield Prediction Model Performance Based on Stacking Technique

Crop growth and development is a dynamic and complex process, and the essence of yield formation is the continuous accumulation of photosynthetic products from multiple fertility stages. In this study, a new stacking method for integrating multiple growth stages information was proposed to improve the performance of the winter wheat grain yield (GY) prediction model. For this purpose, crop canopy hyperspectral reflectance and leaf area index (LAI) data were obtained at the jointing, flagging, anthesis and grain filling stages. In this case, 15 vegetation indices and LAI were used as input features of the elastic network to construct GY prediction models for single growth stage. Based on Stacking technique, the GY prediction results of four single growth stages were integrated to construct the ensemble learning framework. The results showed that vegetation indices coupled LAI could effectively overcome the spectral saturation phenomenon, the validated R2 of each growth stage was improved by 10%, 22.5%, 3.6% and 10%, respectively. The stacking method provided more stable information with higher prediction accuracy than the individual fertility results (R2 = 0.74), and the R2 of the model validation phase improved by 236%, 51%, 27.6%, and 12.1%, respectively. The study can provide a reference for GY prediction of other crops.

Pregnancy and Fertility Trends Among Female Otolaryngologists.

This study sought to determine childbearing patterns and decision making among female otolaryngologists. Anonymous survey. An anonymous survey was sent in 2020 to female otolaryngologists identified through their membership with the American Academy of Otolaryngology-Head and Neck Surgery. Data were analyzed concerning individual fertility and childbearing history, reflections regarding decision making, perceptions of workplace support, and estimations of objective childbearing potential. There were 398 responses. The mean age at first pregnancy was 32.3 years. Almost one-third of respondents who attempted to conceive (30.4%) were diagnosed with infertility. Of those who had their first pregnancy during training, 55% reported having substantial workplace support, as opposed to 70% of those whose first pregnancies followed completion of training (P = .01). When asked what they would do differently in retrospect, most women with infertility (65.0%) would have attempted conception earlier; 41 (41.0%) would have used cryopreservation to extend fertility; and 14 (14.0%) would have gone into a different specialty. Female otolaryngologist respondents have children later in life than the general population, and a substantial proportion face infertility or have regrets about family planning decisions and career decision making. Increased awareness, further investigation, and targeted programs are needed to support the growing number of female otolaryngologists who desire both a career and a family.

Globalization and Gender‐Specific Patterns in Individual Fertility Decisions

AbstractIn the German post‐reunification context dominated by economic uncertainty and structural change, this paper studies the effects of import shocks from China on the fertility decisions of individuals working in the German manufacturing sector between 1995 and 2016. While focusing on trade shocks related to Chinese imported goods, the paper explores individual fertility via the labor market outcomes of manufacturing workers, roughly a fifth of German employment. I investigate the gender‐specific effects of Chinese import competition on individual fertility and explain the channels mediating each of them. I find that globalization affects overall fertility negatively, but the effect is positive for women and negative for men. Results indicate a reduction in the employment opportunity of individuals, an increase in marginal employment and higher economic insecurity. There is a substitution effect in the labor supply of women, here prevalently concentrated in low‐technology sectors: as female earnings fall and their opportunity cost of work is lower, the prospect of having children possibly becomes a more rewarding alternative. Given concerns over low fertility in Germany, findings are particularly important for understanding the German social and economic structure that enabled the country's post‐reunification transformation but also allowed heavy labor market segmentation and atypical work.

Comparative morphological characteristics of spawning populations of Baikal omul (Coregonus migratorius, G.) in the Posolsky Sor, Selenga and Barguzin rivers

The morphological structure, size-age variability and dynamics of age-related fertility of producers of Baikal omul of pelagic, near-bottom and coastal morpho-ecological groups during the depressive state of the population were studied. There is an improvement in the indicators of the growth rate of fish, maturation and an increase in absolute individual fertility against the background of the dilution of the population and the release of the feeding area. A comparative characteristic of some morphological features of fish among morphological-ecological groups is given. The number of gill rakers on the first gill arch significantly distinguishes different morpho-ecological groups and ranges from 36 to 43 pieces for the near-bottom, from 40 to 46 pieces for the coastal and from 44 to 53 pieces for the pelagic morpho-ecological groups. It is noted that the spawning populations of the coastal and pelagic groups are mainly represented by young individuals. With age, the proportion of females increases in all groups. The largest indices of the pectoral, abdominal and anal fins, responsible for movement in the vertical plane, rotation and stop, are noted in the near-bottom group.

Equine Chorionic Gonadotropin as an Effective FSH Replacement for In Vitro Ovine Follicle and Oocyte Development.

The use of assisted reproductive technologies (ART) still requires strategies through which to maximize individual fertility chances. In vitro folliculogenesis (ivF) may represent a valid option to convey the large source of immature oocytes in ART. Several efforts have been made to set up ivF cultural protocols in medium-sized mammals, starting with the identification of the most suitable gonadotropic stimulus. In this study, Equine Chorionic Gonadotropin (eCG) is proposed as an alternative to Follicle Stimulating Hormone (FSH) based on its long superovulation use, trans-species validation, long half-life, and low costs. The use of 3D ivF on single-ovine preantral (PA) follicles allowed us to compare the hormonal effects and to validate their influence under two different cultural conditions. The use of eCG helped to stimulate the in vitro growth of ovine PA follicles by maximizing its influence under FBS-free medium. Higher performance of follicular growth, antrum formation, steroidogenic activity and gap junction marker expression were recorded. In addition, eCG, promoted a positive effect on the germinal compartment, leading to a higher incidence of meiotic competent oocytes. These findings should help to widen the use of eCG to ivF as a valid and largely available hormonal support enabling a synchronized in vitro follicle and oocyte development.

Contribution of Maternal and Paternal Transmission to Bacterial Colonization in Nematostella vectensis.

Microbial communities confer multiple beneficial effects to their multicellular hosts. To evaluate the evolutionary and ecological implications of the animal-microbe interactions, it is essential to understand how bacterial colonization is secured and maintained during the transition from one generation to the next. However, the mechanisms of symbiont transmission are poorly studied for many species, especially in marine environments, where the surrounding water constitutes an additional source of microbes. Nematostella vectensis, an estuarine cnidarian, has recently emerged as model organism for studies on host-microbes interactions. Here, we use this model organism to study the transmission of bacterial colonizers, evaluating the contribution of parental and environmental transmission to the establishment of bacterial communities of the offspring. We induced spawning in adult male and female polyps of N. vectensis and used their gametes for five individual fertilization experiments. While embryos developed into primary polyps, we sampled each developmental stage and its corresponding medium samples. By analyzing the microbial community compositions of all samples through 16S rRNA gene amplicon sequencing, we showed that all host tissues harbor microbiota significantly different from the surrounding medium. Interestingly, oocytes and sperms are associated with distinct bacterial communities, indicating the specific vertical transmission of bacterial colonizers by the gametes. These differences were consistent among all the five families analyzed. By overlapping the identified bacterial ASVs associated with gametes, offspring and parents, we identified specific bacterial ASVs that are well supported candidates for vertical transmission via mothers and fathers. This is the first study investigating bacteria transmission in N. vectensis, and among few on marine spawners that do not brood larvae. Our results shed light on the consistent yet distinct maternal and paternal transfer of bacterial symbionts along the different life stages and generations of an aquatic invertebrate.

The Internet Usage and Individual Fertility Intention：Based on the Perspectives of Information Cost and Family Intergeneration

Fertility is the driving force of population development, while the problem of low fertility has become a new worldwide problem. In the specific context of China, economic and social development dimensions must be taken into account when analyzing the phenomenon of low fertility rate and discussing individual fertility strategies. With the progress of information and communication technology, the Internet is increasingly prominent in its impact on individual reproductive decision-making. We need to pay more attention to the impact of the Internet usage on individual fertility intention. In this context, the comprehensive survey data of Chinese General Social Survey（CGSS2017）is used to investigate the impact of the Internet usage on individual fertility intention. The results show that the higher the frequency of the Internet usage is, the lower the fertility intention of individuals will be. Further research finds that reproductive experience has a negative moderating effect on the impact of the Internet usage on individual fertility intention. For individuals who have already had children, the higher the frequency of the Internet usage is, the more significant the inhibition effect of fertility intention will be. The intergenerational “digital divide” also has a significant negative moderating effect on the impact of the Internet usage on individual fertility intention. When there is a large intergenerational “digital divide” between two generations, for individuals who use the Internet frequently, the conflict between the traditional parenting experience inherited by the parents and the parenting knowledge obtained by the children through the Internet may lead to more family conflicts, thus inhibiting the fertility intention of individuals. On the contrary, when the “digital divide” between generations is small, the inhibition effect of the Internet usage frequency on individual fertility intention also weakens.The main contributions of this paper are as follows: First, from the perspectives of information cost and family intergeneration, the Internet usage is introduced into the research framework of fertility intention to conduct empirical analysis, which expands the related research field. Second, the Internet usage and individual fertility are embedded in a specific context in China to clarify the moderating effect of intergenerational “digital divide” and reproductive experience on the impact of the Internet usage on individual fertility intention, and to provide useful empirical support for exploring solutions to the plight of low fertility.

Interrelationships Among Fertility, Internal Migration,and Proximity to Nonresident Family:A Multilevel Multiprocess Analysis.

Past research has found that relations to nonresident family can influence individual fertility and migration behaviors separately. However, fertility and migration outcomes may also be interrelated, suggesting potential links across all three demographic processes. With this in mind, we track a cohort of women in Norway from age 18 to 31, recording the emergence of birth and migration events as well as their proximity to nonresident family networks (siblings and parents). Using a multilevel multiprocess statistical framework, with observations nested within women and equations for births, migrations, and proximity to nonresident family estimated simultaneously, our results support the notion that linked lives matter. Even in early adulthood, proximity to nonresident family has a positive effect on transitions to motherhood, whereas the presence of children (itself an outcome of past fertility) is associated with lower propensities to migrate. Mothers also have higher propensities to be living near family than women without children. The presence of local nonresident family reduces propensities for second and third migrations. However, after accounting for unobserved heterogeneity and selection, we observe a small positive effect of proximity to family on first migrations undertaken after age 18. Significant cross-process residual correlations exist across all three outcomes, suggesting that separately estimated model estimates may be vulnerable to bias emerging from unobserved sources of heterogeneity and selection. Our analysis therefore suggests that decisions about fertility, migration, and proximity to family are jointly determined and endogenous, and they should be analyzed simultaneously when possible.

О ПЛОДОВИТОСТИ СЕЛЬДИ-ЧЕРНОСПИНКИ ALOSA KESSLERI KESSLERI (GRIMM, 1887)

The article highlights the results of studying the individual absolute fertility (IAF) of black-backed shad Alosa kessleri kessleri (Grimm, 1887). The data were obtained during the species’ spawning run in the Volga River. A positive correlation was established between IAF and the linear indicators, weight and age of producers. IAF ranged from 38.0 to 333.9 thousand eggs. The average absolute fecundity of herring varied from 38.8 to 259.2 thousand eggs. In the 1970s black-backed shad of 26-42 cm long had fluctuations in the average absolute fecundity from 88.4 to 258.5 thousand eggs. At the present stage, the size range of spawning shoals suggests that maturity in black-backed shad occurs at a body length of 22-45 cm, the reproductive capacity is regulated by early maturation. The results of studies on the fertility of black-backed herring of various lengths in 1 g of ovary have been obtained. There has been registered a wide range of fluctuations in the number of eggs (from 4033 to 14147 pcs). Differences in the size of ovaries indicate a qualitative definiteness of the physiological readiness of females in the pre-spawning period. The fluctuations in the average individual absolute fertility were revealed depending on body weight and age. Fertility in one-size groups and the reproductive capacity of the population as a whole change due to habitat conditions. The conditional indicator of the population fertility was calculated. The results of the obtained fertility data compared with the data of previous years indicate a 1.5-fold decrease in reproductive capacity of the population at the present time, which indicates a stressed state of the reproductive capacity of female species

Effect of host switching simulation on the fitness of the gregarious parasitoid Anaphes flavipes from a novel two-generation approach

Herbivorous insects can escape the strong pressure of parasitoids by switching to feeding on new host plants. Parasitoids can adapt to this change but at the cost of changing their preferences and performance. For gregarious parasitoids, fitness changes are not always observable in the F1 generation but only in the F2 generation. Here, with the model species and gregarious parasitoid Anaphes flavipes, we examined fitness changes in the F1 generation under pressure from the simulation of host switching, and by a new two-generation approach, we determined the impact of these changes on fitness in the F2 generation. We showed that the parasitoid preference for host plants depends on hatched or oviposited learning in relation to the possibility of parasitoid decisions between different host plants. Interestingly, we showed that after simulation of parasitoids following host switching, in the new environment of a fictitious host plant, parasitoids reduced the fictitious host. At the same time, parasitoids also reduced fertility because in fictitious hosts, they are not able to complete larval development. However, from a two-generation approach, the distribution of parasitoid offspring into both native and fictitious hosts caused lower parasitoid clutch size in native hosts and higher individual offspring fertility in the F2 generation.

Reproductive Aging in Caenorhabditis elegans: From Molecules to Ecology.

Aging animals display a broad range of progressive degenerative changes, and one of the most fascinating is the decline of female reproductive function. In the model organism Caenorhabditis elegans, hermaphrodites reach a peak of progeny production on day 2 of adulthood and then display a rapid decline; progeny production typically ends by day 8 of adulthood. Since animals typically survive until day 15 of adulthood, there is a substantial post reproductive lifespan. Here we review the molecular and cellular changes that occur during reproductive aging, including reductions in stem cell number and activity, slowing meiotic progression, diminished Notch signaling, and deterioration of germ line and oocyte morphology. Several interventions have been identified that delay reproductive aging, including mutations, drugs and environmental factors such as temperature. The detailed description of reproductive aging coupled with interventions that delay this process have made C. elegans a leading model system to understand the mechanisms that drive reproductive aging. While reproductive aging has dramatic consequences for individual fertility, it also has consequences for the ecology of the population. Population dynamics are driven by birth and death, and reproductive aging is one important factor that influences birth rate. A variety of theories have been advanced to explain why reproductive aging occurs and how it has been sculpted during evolution. Here we summarize these theories and discuss the utility of C. elegans for testing mechanistic and evolutionary models of reproductive aging.

Ion-Exclusion/Cation-Exchange Chromatography Using Dual-Ion-Exchange Groups for Simultaneous Determination of Inorganic Ionic Nutrients in Fertilizer Solution Samples for the Management of Hydroponic Culture

In this study, ion-exclusion/cation-exchange chromatography (IEC/CEC) using dual-ion-exchange groups (carboxy and sulfo groups) for the simultaneous determination of anions (SO42−, Cl−, NO3−, and HPO42−) and cations (Na+, NH4+, K+, Mg2+, and Ca2+) was developed. By using the combination of dual-ion-exchange groups, simultaneous separation of inorganic ions with HPO42− was achieved that was impossible by the conventional IEC/CEC based on the single-ion-exchange group (carboxy group). This method was applied to the monitoring of inorganic ionic nutrients in fertilizer solution samples in hydroponic culture. As a result, a higher peak resolution of inorganic anions and cations with phosphate ion using IEC/CEC with dual-ion-exchange groups was achieved in the absence of matrix effects. In addition, the developed method helps to understand the behavior of ionic nutrients in fertilizer solution during hydroponic cultivation and is potentially useful for the individual fertilization of ionic nutrients.

P–738 Fertility Preservation: Comparative analysis about the knowledge of the topic between two female populations in Argentina and the United States

Abstract Study question Is there any difference in the knowledge that women in Córdoba (Argentina) and South Carolina (United States) have about fertility preservation, according to their socioeconomic and educational level? Summary answer Scarce knowledge about fertility preservation in both populations was registered. Only sectors of higher socioeconomic and educational level responded correctly with values close to 60%. What is known already There are numerous factors that may motivate the need to preserve fertility in young individuals. These factors can be grouped into two causes: social (postponement of motherhood, gender change, etc.), or medical (oncological or surgical treatments). In these situations, it is important that society in general has access to information about fertility and the possibilities of preserving it, if necessary. On the other hand, in each country and region in particular the information on this topic is distributed in different ways, which could generate differences in the level of knowledge on these issues in different population groups. Study design, size, duration Descriptive quantitative study. A total of 3,041 answers were obtained, 88.8% from Argentina and 10.00% from the United States. An 83.72% (2,521) of the answers were made by women. Participants/materials, setting, methods A closed-ended questionnaire of 20 questions was designed (segmentation and aspects of knowledge about fertility and its preservation) and distributed to different sectors of society through social networks. The survey was answered by people from Córdoba (Argentina) and South Carolina (US), of both sexes and different age groups, educational levels (basic/higher) and socioeconomic levels (medium-low/high). All answers were collected through SurveyMonkey and were analyzed using calculation programs and statistical tools (Excel 2016, Statistica 8.0). Main results and the role of chance Data showed that the 47.98% of Argentine women and 42.68% of American women surveyed do not know the age at which fertility begins to decline. The group with the highest percentage of incorrect answers (61.11%) for this question was that of Argentine women who had no previous experience with assisted fertility and come from the lower-middle social class. When asked about the knowledge about the factors that affect fertility, only 55% of Argentine women answered correctly, compared to 64.85% of American women. For the Argentine group, the proportion of correct answers increased to 62.23% for higher education level and to 56.60% for higher socioeconomic level. Regarding whether they know what fertility preservation procedure consists of, only 47.98% of Argentine women and 42.68% of American women answered correctly. On the other hand, 69.37% of the former and 63.18% of the latter do not know which biological materials can be cryopreserved. Finally, only 25.68% of women in Argentina know about the extent of their medical coverage in terms of fertility preservation procedures, while this percentage is 7.95% for the US population. Limitations, reasons for caution The comparison between the two countries may be challenged by the inequality in the response rate to the survey. However, even the smaller number of responses obtained in the USA is sufficient to obtain valid conclusions. Wider implications of the findings: The level of misinformation registered in this study could imply reduced chances of achieving pregnancy in the future, especially for older women, those who wish to postpone motherhood or those who must undergo cancer treatments. This work provides important information in the politics designing promoting information access on fertility preservation. Trial registration number .

P–111 Development of a flow cytometric assay for membrane lipid oxidation in human sperm

Abstract Study question Is a commercially available lipid peroxidation assay sensitive enough to detect sperm lipid membrane damage and thus provide a novel indicator of male fertility status? Summary answer Provisional results demonstrate the novelty of creating a protocol to identify and quantify sperm lipid membrane damage and indicate possible insight into individual male fertility. What is known already Cytotoxic lipid aldehydes such as 4-hydroxynonenal (4HNE) created by the damaging effects of reactive oxygen species (ROS) have been studied extensively in sperm, as an indicator of male fertility. This is due to their connection with detrimental effects on sperm function such as morphology, acrosome reactions, motility and fertilization of the oocyte. Although literature states the mechanisms of damage caused to the lipid membrane of the sperm cell, there is no evidence of its quantification or usage as a commercial fertility indicator for human males. Study design, size, duration Since the assay is still being developed, there is no formal study size or duration. The goal of this pilot study is to determine whether a commercial lipid peroxidation assay can detect the difference between sperm with high levels of oxidative damage and control sperm cells. We used the remains of sperm samples initially collected for standard semen analysis, which were flash-frozen and then assayed with / without hydrogen peroxide treatment to induce oxidative damage. Participants/materials, setting, methods Frozen sperm from consenting donors (n = 21) were washed, optionally treated with hydrogen peroxide to induce oxidative damage, stained with a commercially available lipid peroxidation sensor (LPS, Abcam ab243377), and the resulting fluorescence quantitated by flow cytometry. Assay optimization varied the numbers of sperm input to the protocol, the concentration of the peroxidation sensor, the amount and duration of hydrogen peroxide treatment and the effect of paraformaldehyde (PFA) fixation of samples before or after staining. Main results and the role of chance Successful detection of lipid damage in control samples We observed a significant difference at a p-value < 0.05 between untreated samples and all positive controls with hydrogen peroxide concentrations stronger than 500uM (p < 0.038) . This indicates that we can detect sperm bearing oxidative damage, and establishes the conditions required to make a positive control sample. Establishment of assay parameters Results indicate the concentration of sperm input to the protocol is not a significant factor for concentrations below 5 million/ml. Low concentration samples thus do not require further dilution before testing. Correlation with DNA damage A significant direct strong positive Pearson correlation coefficient (R = 0.93, p < 0.023) was found between samples with low DNA fragmentation index (DFI (%), measured by flow cytometric staining with acridine orange) and the LPS flow cytometric data (%). Limitations, reasons for caution As yet our data only addresses high level lipid damage induced by peroxide treatment. It remains to be established whether it is possible to detect endogenous LPO damage due to oxidative stress in semen. Future work will correlate our data with motility information and oxidative stress data (measured by MiOXSYS). Wider implications of the findings: If we are able to develop a direct assay for sperm LPO, this will allow an additional avenue for testing patients with unexplained male infertility, which could in turn affect treatment choices and ART methodology. Improved diagnosis and treatment will potentially improve the lives of families with their fertility matters. Trial registration number Not applicable

IoFarm: A novel decision support system to reduce fertilizer expenditures at the farm level

Farmers and consultants make the best use of existing resources to increase profitability, and this begins at the operating resources level. Existing literature primarily deals with the optimal intensity of fertilization. A multitude of different fertilizers, with fluctuating price ratios, however, promises an additional economic optimization potential that can be achieved by cleverly combining these fertilizers to form a least-cost combination. This potential is extended if individual costs of fertilizer application are considered in parallel. The objective of the IoFarm decision support system is to take up this overall complex and to determine individual fertilizer strategies for farms, which also determines the economic optimization potential. In terms of methodology, the solution to this problem is based on mixed integer nonlinear programming (MINLP). The restrictions and parameters used for this were taken from the literature and where necessary were derived in a simplified form in order to keep usability a practical tool. The subsequent evaluation of the economic performance was carried out by conducting an experiment. The participants were asked to define a fertilizer strategy for a simplified farm with three fields and three crops over three years. Despite the considerable amount of time it took the testers to conduct this investigation, IoFarm performed 19% better in terms of costs. Our results show surprisingly clearly the complexity of this decision-making process and the previously unused monetary and time optimization potential behind it. The agronomic performance of IoFarm has already been confirmed in another study.

Protective effect of the Prunella grandiflora L. extract in relation to the toxic effect of etoposide through the example of Drosophila melanogaster

The data on the protective properties of the Prunella grandiflora L. extract were obtained when used together with the anticancer drug etoposide on the experimental strain of Drosophila melanogaster . The combined use of etoposide and 10% extract of P. grandiflora decreased mortality in D. melanogaster individuals to 15% and doubled the average individual fertility compared to the use of this cytostatic drug without the extract. Using the SMART method, the presence of the antigenotoxic effect was identified, which manifests itself through the absence of chromosomal aberrations.

PEER EFFECTS AND FERTILITY PREFERENCES IN CHINA: EVIDENCE FROM THE CHINA LABOR-FORCE DYNAMICS SURVEY

Despite empirical evidence that individuals form their fertility preferences by observing social norms and interactions in their environments, the exact impact of these peer effects remains unclear. We thus use data from the 2014 and 2016 China Labor-force Dynamics Survey to investigate the association between community-level peer effects and fertility preferences among Chinese women aged 18–49. Whereas our baseline results indicate that 11.96% of these women would prefer 1 or no children, 74.1% would like 2 children and 13.93% would prefer 3 or more children. A one unit increase in community-level peer fertility reduces the preference of wanting only one child by 14.3%, whereas it increases the probability of preferring three children by 9.3% and four or more children by 4.8%. Hence, overall, we find a relatively strong peer effect on individual fertility preferences in communities characterized by generally low fertility rates, which provide support for the role of social norms in the fertility choices of reproductive-aged Chinese women.

Interspecific hybrids of animals - in nature, breeding and science – a review

Abstract Interspecific hybrids called hybrids are individuals obtained by crossing two different species. Hybrids are found both in nature among wild animals but also have become attractive in animal husbandry due to the high production features of the F1 generation. Interspecific hybrids are observed in nature most often as a result of crossing closely related species, which is a great danger to the purity of the population of starting species. Interspecies hybrids are also created by man for production purposes. Due to disturbances in gametogenesis processes, they have become a valuable research model. In the article, we describe interspecific hybrids occurring in nature and related problems, interspecific hybrids created for production purposes in animal husbandry, but also research using hybrids as a research model. In the article we also highlight the issues of fertility of individuals obtained from such matings.