Amino-nanopolystyrene exposures of oyster (Crassostrea gigas) embryos induced no apparent intergenerational effects.

Early life stages (ELS) of numerous marine invertebrates mustcope with man-made contaminants, including plastic debris, during their pelagic phase. Among the diversity of plastic particles, nano-sized debris, known as nanoplastics, can induce effects with severe outcomes in ELS of various biological models, including the Pacific oyster Crassostrea gigas. Here, we investigated the effects of a sub-lethal dose (0.1 µg mL-1) of 50 nm polystyrene nanobeads (nano-PS) with amine functions on oyster embryos (24 h exposure) and we assessed consequences on larval and adult performances over two generations of oysters. Only a few effects were observed. Lipid analyses revealed that first-generation (G1) embryos exposed to nano-PS displayed a relative increase in cardiolipin content (+9.7%), suggesting a potential modification of mitochondrial functioning. G1-larvae issued from exposed embryos showed decreases in larval growth (-9%) and lipid storage (-20%). No effect was observed at the G1 adult stage in terms of growth, ecophysiological parameters (clearance and respiration rates, absorption efficiency), or reproductive outputs (gonadic development, gamete quality). Second generation (G2) larvae issued from control G1 displayed a significant growth reduction after G2 embryonic exposure to nano-PS (-24%) compared to control (as observed at the first generation), while no intergenerational effect was detected on G2 larvae issued from G1 exposed embryos. Overall, the present experimental study suggests a low incidence of a short embryonic exposure to nano-PS on oyster phenotypes along the entire life cycle until the next larval generation.

Nanopolystyrene beads affect motility and reproductive success of oyster spermatozoa (Crassostrea gigas).

Oysters are keystone species that use external fertilization as a sexual mode. The gametes are planktonic and face a wide range of stressors, including plastic litter. Nanoplastics are of increasing concern because their size allows pronounced interactions with biological membranes, making them a potential hazard to marine life. In the present study, oyster spermatozoa were exposed for 1 h to various doses (from 0.1 to 25 µg mL-1) of 50-nm polystyrene beads with amine (50-NH2 beads) or carboxyl (50-COOH beads) functions. Microscopy revealed adhesion of particles to the spermatozoa membranes, but no translocation of either particle type into cells. Nevertheless, the 50-NH2 beads at 10 µg mL-1 induced a high spermiotoxicity, characterized by a decrease in the percentage of motile spermatozoa (-79%) and in the velocity (-62%) compared to control spermatozoa, with an overall drop in embryogenesis success (-59%). This major reproduction failure could be linked to a homeostasis disruption in exposed spermatozoa. The 50-COOH beads hampered spermatozoa motility only when administered at 25 µg mL-1 and caused a decrease in the percentage of motile spermatozoa (-66%) and in the velocity (-38%), but did not affect embryogenesis success. Microscopy analyses indicated these effects were probably due to physical blockages by microscale aggregates formed by the 50-COOH beads in seawater. This toxicological study emphasizes that oyster spermatozoa are a useful and sensitive model for (i) deciphering the fine interactions underpinning nanoplastic toxicity and (ii) evaluating adverse effects of plastic nanoparticles on marine biota while waiting for their concentration to be known in the environment.

Stay or leave? Individual choice and family logic: the destinations of children born in the Valserine Valley (French Jura) in the eighteenth and nineteenth centuries.

"To study inheritance, it is necessary in the first place to know the number of heirs in each family, how property was divided between them, and whether their inheritance was sufficient to enable them to maintain and support several children in the parish. This study examines the process by which the populations of the parishes of Valserine Valley in France reproduce themselves from one generation to the next, by means of examining the ¿effective' progeny of couples to determine how many of them produce children (heirs) who continue to live in the Valley. The ultimate goal of these researches is to establish the characteristics of those who leave the Valley, and how these differ from those who choose to stay. The article examines whether it is possible to discern a family strategy in the way these decisions are made, and whether behavior of the persons in question is determined by individual choice."

[The reproduction of the population in the seventeenth, eighteenth, and nineteenth centuries. Examples from France and Quebec]. / La reproduction de la population aux XVIIe, XVIIIe et XIXe siècles. Exemples français et québecois.

This article examines the descendants of four cohorts of couples formed in the seventeenth and eighteenth centuries (two cohorts in two French mountain valleys and one on the Ile-d'Orléans in Quebec). The children are separated into four categories according to their fate (deceased while still unmarried, unknown fate, married but childless, "useful children"). "Useful children", a concept used in population genetics, are those who in turn bear children. In all three places, the useful children represent only from 26 to 31% of births. The study goes on to measure the contributions made by these couples to the next generation. In the mean, each couple gave birth to little over one useful child. But the contributions of couples turns out to be very unequal. Depending on the place, from 36 to 53% of couples left no useful children behind them, while a small minority of couples made an ample contribution to the next generation. The same measure is reproduced in the constitution of the next generation, thereby showing that inequality of couples in terms of reproduction is perpetuated.

Age of mother at last birth in two historical populations.

This study uses sets of historical family reconstitutions from all of Quebec and from four villages of the Haut-Jura, France--first marriages of 2226 and 994 women, respectively--to investigate the physiological and social factors affecting age of mother at last birth before and during fertility transition. Age remained high throughout the period covered in Quebec, under 'natural' conditions, but showed a steady decline in the French material which extends to late 19th century generations practising family limitation. Age at marriage had no influence in Quebec; in France, however, women with the most surviving children at age 35 continued childbearing the latest. There was no link between biological ability to achieve a live birth, or in health status or aging rhythm, and age at last birth. Behaviour of mothers and daughters showed no relation. The variability in age at last birth thus appears to be random under natural conditions; with the onset of controls, social differences seem to influence not only the end of childbearing, but all aspects of behaviour governing final family size and child survival.

PIP: The study of the cessation of childbearing in natural fertility populations has yielded mixed results. This study examined the physiological and social factors affecting the maternal age at last birth before and during fertility transition. Data were obtained from linked registries of baptisms, marriages, and burials compiled at the University of Montreal. The data set of 2226 women born between 1624 and 1715 included the entire French Canadian population living in the Province of Quebec between 1608 and 1765 for births and 1799 for deaths. This time period corresponded to a natural fertility regimen, and toward the end of the period the youngest had begun spacing of the last birth interval. Another data set of 994 women born before 1900 pertained to four French villages of Haut-Jura from 1680 through the French fertility transition. The sample included only women with an exact birth date, a first marriage, and the last child born being born around the age of 30 years. The Canadian women had a mean and median age of marriage of 21 years and a mode of 19 years. Early marriage was prevalent, and 50% of births occurred after 1694. About 50% of women had 8-12 children, with the average being 11 children; the highest number was 20 or more. The French women spanned 2.5 centuries and the mean was the year 1800. The average marriage age was 23.7 years and the average number of children was 6; 14 children was the highest number. The results showed that the French Canadian women bore their last child at an average age of 41.5 years compared to 39.5 years for the French women. The age at last birth declined over time in the French sample to below 38 years after 1840. The French Canadian sample showed 50% of women ending childbearing around the age of 40 years and 70% of women doing so in the 37-44 age span. Marriage age was unrelated to last birth in the Quebec sample, and length of first birth interval was unrelated in either sample. The French sample showed that age at last birth increased with age at marriage, thereby suggesting stopping behavior. Mothers with 4 children at the age of 35 years had their last child a year later than those with 3 children. Age at last birth was not related to daughter's age at last birth. Stopping behavior was more related to age than norms about appropriate numbers of children.

[The difference in mortality between biological children and foster children: the example of Druillat (Ain) in the seventeenth century]. / Mortalité différentielle des enfants indigènes et des enfants en nourrice. L'exemple de Druillat (Ain) au XVIIe siècle.

Druillat, a parish in Bresse, welcomed a lot of abandoned infants who had been found a foster home by Lyons Hôtel-Dieu (hospital) during the second half of the eighteenth century. After specifying the annual volume of this incoming flow, the arrival of each infant at its foster home is considered. The notion of foster home covers in diversified family situations as far as the number of native children and infants are concerned. Through the comparison of deaths recorded locally and the Hôtel-Dieu register keeping lists of the infants' placements, the mortality of foster infants can be precise and compared to that of natives. The age at which they were put out to nurses and the host family standards of living, plays a fundamental role as far as the infant mortality risks are concerned.

An abnormal concentration of cases of Rendu-Osler disease in the Valserine valley of the French Jura: a genealogical and demographic study.

An important concentration of patients with Rendu-Osler disease occurs in the Valserine valley of the French Jura. A study of marriages shows that, in spite of its somewhat remote location, the valley cannot be considered an isolate, but that, on the contrary, exogamy is widely practised. Only 17.8% of the genes of inhabitants during the present century can be traced to the original population, but persons affected with the disease belong to a subgroup of the population which has lived in the villages for more than 10 generations. All the patients in 85 sibships are related. The smallest number of originator couples who lived at the beginning of the eighteenth century amounts to 16, the unique originator may therefore have lived approximately four generations earlier. However, as other patients who lived at the periphery of the Valserine valley do not appear to be related to any patients living in the valley, and because there has been considerable immigration into the valley, a number of hypotheses to explain the distribution of the disease in the region remain possible.

Intervals between marriage and first birth in mothers and daughters.

Marriage-first birth intervals are examined in two historical populations, Quebec (1608-1765) and Haut-Jura (1689-1980), comparing intervals in mothers and daughters, and in sister-sister pairs. The results point to a weak relationship between intervals of mothers and daughters, though it does not attain significance. Shared environment does not seem to be responsible since there is no association between pairs of sisters from the same populations.

Epidemiological investigation of Rendu-Osler disease in France: its geographical distribution and prevalence.

PIP: The authors explore the spatial distribution by geographic department of Rendu-Osler disease in France. They analyze the prevalence of this inherited disease and follow its development by tracing internal migration patterns. Data are from a 1984 survey.^ieng

Age-related clinical profile of hereditary hemorrhagic telangiectasia in an epidemiologically recruited population.

We report the results of a comprehensive and systematic clinical study of 324 patients with hereditary hemorrhagic telangiectasia, selected from a total of 1,270 cases recruited by epidemiological survey. In 94% of the cases, familial occurrence suggested autosomal dominant inheritance; maximum penetrance for at least one manifestation was 97%. Epistaxis was reported by 96% of the patients and, in more than 50%, developed before age 20. Heavy and frequent bleeding occurred mainly in middle-aged patients. Telangiectasia was documented in 74% of cases, half of whom were younger than 30 years. The frequency of involvement of the hands and wrists was 41%, and for the face, 33%. Visceral involvement was present in 25% of patients, with affected lungs and CNS in the young and gastrointestinal tract and liver in older patients. Symptomatic urinary tract involvement was seen in only two/324 patients. Involvement of other internal sites was not observed.

[Orphans and adult mortality. The example of France between 1740 and 1829]. / Los huerfanos y la mortalidad adulta. El ejemplo de Francia de 1740 a 1829.

The relationship between adult mortality and the proportion of orphans in France in the eighteenth and nineteenth centuries is analyzed. Data are from a research project developed at the Institut National d'Etudes Demographiques [INED] and concern data for some 400 communes, together with life tables developed for the periods 1740-1749 and 1820-1829. "This paper is divided in two chapters. The first chapter examines the different proportions of orphans, observed in the above mentioned periods. The second one confronts these proportions with comparable values derived from mortality tables." Consideration is given to the relationship between parents' death and timing of marriage of

[Demography and genetics. The usefulness of geneologic data banks]. / Démographie et génétique. De l'utilité des banques de données généalogiques.

The authors have tried to answer an essential question: the usefulness of data bases in Genetics and Demography. Problems concerning the collect and the treatment by computer of registers of population have been presented. The usefulness of the genealogic reconstitutions for all the fields of the research, particularly for historic demography, genetic and medical research, both basic and applied, is presented.

[Not Available]. / Accouchement "Naturel" et accouchement à "haut risque".

PIP: A study of maternal mortality in France is presented for the period 1660 to 1814 based on family reconstitution data for the village of Mogneneins. The data suggest that 2.35 percent of all women died giving birth. Trends in maternal mortality and causes of death are analyzed over this period. Death rates were higher for mothers having their first birth and for those undergoing high-risk deliveries, such as multiple births or stillbirths. The value of the presence of physicians and midwives at childbirth is emphasized. (summary in ENG)^ieng