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Bandyopadhyay Mridula - - 2003
Survival chances of girls in parts of South and East Asia have been adverse. Female foeticide, infanticide, abandonment, out-adoption, under-reporting of female births, and selective neglect of girls leading to higher death rates, have contributed to this adversity. Here, I reflect on an observed skewed sex ratio at birth in ...
Haccou Patsy - - 2003
When several competitors deplete a patch, it can be advantageous for each of them to stay provided that others leave, whereas, on the other hand, staying longer decreases the expected payoff for everyone. This situation can be considered as a generalized war of attrition. Previous studies have shown that optimal ...
Ma S - - 2003
We investigated the aetiology of the male phenotype in a premature infant derived from ICSI with a 46,XX karyotype. A karyotypically normal couple underwent ICSI because of obstructive azoospermia in the male partner. Sperm were retrieved by testicular sperm extraction (TESE), cryopreserved, and later used for ICSI. The pregnancy after ...
Schradin Carsten - - 2003
In biparental species, females are thought to accept and even to seek male assistance in rearing of the young. In this study, we present data that suggests that Goeldi's monkey females (Callimico goeldii) actually reject male parental care for a certain period. In Callimico, which have biparental care, mothers carry ...
Simorangkir David R - - 2003
Although a marked pubertal increase in Sertoli cell number is a hallmark of testicular development in the rhesus monkey, the ontogeny of this somatic cell type before puberty is less clear. To clarify this issue, groups (n = 4) of neonate (1-2 d old), infant (4-5 months old), juvenile (14-17 ...
Bardi Massimo - - 2003
The subtle and complex relationships between the sequential maturation of the endocrine systems during pregnancy and parturition, and the hormonal role in activating the central nervous system to express maternal behavior in primates, are far from being completely understood. Recent studies on the association between sex steroids and maternal behavior ...
Lachance Marc André - - 2003
Biodiversity theory proposes two types of hypotheses to account for the species composition of a given community. The first encompasses geographic and historical factors. For example, local species richness is thought to be affected by area, proximity to large landmasses, dispersal mechanisms, and climatic history, collectively known as biogeography. The ...
Saito Yasunori - - 2003
The morphology and life history of a strange and unidentified botryllid ascidian were investigated. This ascidian was first collected from the stony shore of Ebisu Island in Shimoda, a city on Izu peninsula in central Japan. Unlike other botryllid ascidians, whose colonies are flat and smooth, this ascidian's colonies are ...
Bearder Simon K - - 2003
This paper provides a checklist and summary of what is currently known of the variation in infant contact, sleeping site preference and aspects of social cohesion in the nocturnal primates of Africa. Genera and species are compared, based on previously unpublished field observations and a review of the literature. There ...
Nekaris K A I - - 2003
Studies of the life history parameters of slender lorises in captivity have led to conflicting results regarding gestation length, birth seasonality, interspecies variation in litter size and the degree of parental care given to offspring. During the course of field studies of Loris lydekkerianus lydekkerianus, L. l. nordicus and L. ...
Schelegle Edward S - - 2003
Twenty-four infant rhesus monkeys (30 days old) were exposed to 11 episodes of filtered air (FA), house dust mite allergen aerosol (HDMA), ozone (O3), or HDMA + O3 (5 days each followed by 9 days of FA). Ozone was delivered for 8 h/day at 0.5 ppm. Twelve of the monkeys ...
De Vleeschouwer Kristel - - 2003
Reproduction is highly demanding in terms of energy expenditure, and the costs and benefits associated with postponing or investing in a reproductive effort are crucial determinants of an individual's fitness. Understanding the reproductive potential of a species under varying ecological conditions offers important insights into the dynamics of its social ...
Marrocco G - - 2003
Cryptorchidism and proximal hypospadia in a newborn are highly suspicious for an intersex disorder, and proper investigations should be planned immediately after birth. In some hypospadic patients, the presence of a palpable gonad in the scrotum may induce to assign the male sex, whereas the anatomy of internal and external ...
Niva Cintia Carla - - 2003
Influences of photoperiod, temperature and melatonin were examined on development and color patterns of nymphs, and sternum color and reproductive fate of adults in Halyomorpha halys (brevis). Short-day accelerated nymphal development, whereas long-day accelerated reproductive maturation. The two types of photoperiodic responses at different stages may help maintain the univoltinism ...
Kennedy Michael D - - 2003
The purpose of this study was to determine the race profile for a 2000-m simulated rowing race as well as the effect of training and gender on the race profile. Nineteen men and 19 women undertook a 2000-m simulated rowing race before and after 10 weeks of a typical off-season ...
Schaal Benoist - - 2003
Mammals owe part of their evolutionary success to the harmonious exchanges of information, energy and immunity between females and their offspring. This functional reciprocity is vital for the survival and normal development of infants, and for the inclusive fitness of parents. It is best seen in the intense exchanges taking ...
Swedell Larissa - - 2003
In this work we report the first observational evidence of infanticide in wild hamadryas baboons. The study group inhabits the lowlands of the northern Rift Valley in Ethiopia and has been under observation for over 1,200 hr, on and off, since October 1996. Here we report observations from August and ...
Schradin Carsten - - 2003
The authors explored whether prolactin is associated with paternal care in 3 monkey species: titi monkey (Callicebus cupreus), common marmoset (Callithrix jacchus), and Goeldi's monkey (Callimico goeldii). They compared prolactin levels in fathers before and after infant birth as well as between fathers and nonfathers. C. cupreus fathers carry infants ...
Havill L M - - 2003
Although published normative reference standards for hematologic and clinical chemistry measures are available for adult baboons, their applicability to infants has not been addressed. We analyzed these measures in 110 infant baboons (55 females and 55 males) from a large breeding colony at the Southwest Regional Primate Research Center in ...
Herman Rebecca A - - 2003
Yearling rhesus monkey females interact more with infants than do males. However, the continuity of this sex difference throughout the juvenile period is unknown. Human females display similar sexually differentiated interest in infants, and studies of girls with congenital adrenal hyperplasia suggest that this sex difference may be modulated by ...
Foulds Nicola - - 2003
Sedaghatian type spondylometaphyseal dysplasia is a rare osteochondrodysplasia first described in 1980. The original report describes an Iranian infant with mild rhizomelic limb shortening, severe metaphyseal cupping and irregularity and platyspondyly who died shortly after birth. The baby was born to a consanguineous couple who had reportedly had two similarly ...
Uller Claudia - - 2003
Techniques traditionally used in developmental research with infants have been widely used with nonhuman primates in the investigation of comparative cognitive abilities. Recently, researchers have shown that human infants and monkeys select the larger of two numerosities in a spontaneous forced-choice discrimination task. Here we adopt the same method to ...
Schara Ulrike - - 2003
X-linked myotubular myopathy usually affects male infants with a severe phenotype leading to early death or survival with severe handicaps. Female carriers have been reported manifesting in childhood with slowly progressive muscle weakness only. The authors describe a now 5-year-old girl with prenatal/neonatal onset of an X-linked myotubular myopathy due ...
Ku Sujin - - 2003
The tapetum plays a crucial role in pollen development. This secretory tissue produces numerous nutritive proteins necessary for pollen maturation. The tapetum, whose cells undergo programmed cell death (PCD), is completely diminished by the time the pollen is fully mature. Our previous studies on a thermosensitive genic male-sterile (TGMS) rice ...
Inglis G D - - 2003
The utility of using meconia to nondestructively detect entomopathogens of lepidopterous heliothines was examined. Early-instar tobacco budworm [Heliothis virescens (F.)] or cotton bollworm [Helicoverpa zea (Boddie)] larvae were inoculated with cytoplasmic polyhedrosis virus (CPV), Serratia marcescens Bizio, or Nosema heliothidis Lutz and Splendor, and the presence of each of the ...
Tolasch Till - - 2003
Extracts of Amphimallon solstitiale (L.), a well known, widely distributed and rather common European scarab beetle, were analyzed by GC-MS and GC-EAD. Acetoin - (R):(S) > 9:1 - as well as 2,3-butanediol - (2R,3R): (2S,3S):meso = 1:1:9 - were present in extracts of both males and females. Although (2S,3S)-butanediol did ...
Pawłowski Bogusław - - 2003
Among primates, the genus Homo has a unique sexual dimorphism in general body shape. The stenotypic female "hourglass figure" has often been attributed to sexual selection. Sexual dimorphism both in shape and in position of the center of body mass (CoM) emerges during puberty and is related to hormonal influences. ...
Schneider Johanna S - - 2003
Neuroendocrine mechanisms that mediate male aggression toward infants are poorly understood. Although testosterone is known to enhance aggression in other social contexts, evidence that it modulates aggression toward infants is equivocal. We have found that male progesterone receptor knockout (PRKO) mice exhibit no infanticidal behavior and little aggression toward young. ...
Russell A J - - 2003
In eutherian mammals, sex differentiation is initiated by expression of the testis-determining gene on the Y chromosome. Subsequent phenotypic development of the reproductive tract and genitalia depends on the production of hormones by the differentiated testis. In marsupials the mechanisms of phenotypic development may vary from this pattern, as differentiation ...
Morbey Yolanda E - - 2003
We use a game-theoretic framework to investigate the reproductive phenology of female kokanee (Oncorhynchus nerka). As in the other semelparous species of Pacific salmon, females construct nests in gravel, spawn with males, bury their fertilized eggs, and defend their nest sites until they die several days later. Later-breeding females may ...
Komdeur Jan - - 2003
The Seychelles warbler (Acrocephalus sechellensis) was an endangered endemic of the Seychelles islands where, until 1988, the entire population of ca. 320 birds was restricted to the one island of Cousin Island (29 ha). Additional breeding populations were successfully established on the islands of Aride (68 ha, 1988) and Cousine ...
van Balen Frank - - 2003
Throughout recorded history, humans have tried to influence the sex of their offspring, through pregnancy injunctions, infanticide, and infant/child neglect. Reproductive technologies developed in the late 20th century allow determination of the sex of the offspring during pregnancy, making "sex selection" through abortion possible. Especially in parts of East and ...
Kinnberg Karin - - 2003
Endocrine disrupting alkylphenolic compounds have been found in the aquatic environment, and concern has arisen over the ability of these compounds to affect the reproductive system of fish. In this study, the effects of exposure to an environmentally relevant concentration of octylphenol or 17beta-estradiol on the gonad structure of fish ...
Levine Seymour - - 2003
Long-term effects of early experiences have been well documented in rodents, non-human primates and humans. The influence of early experiences on the regulation of the hypothalamic-pituitary-adrenal has demonstrated that this biological system is highly plastic and is permanently modified by early experiences. The effects of brief periods of maternal separation ...
Melo L - - 2003
Infanticide has been observed in many different species [1], including common marmosets [2-4], due to sexual selection, reproductive strategies or resource competition [3, 5, 6], which may ultimately lead to exploitation (cannibalism) [1, 7]. Wild callithrichids have a very flexible mating system, including monogamy, polygynandry, polyandry and polygyny [4, 8, ...
Hennessy Michael B - - 2003
During observations in the home cage in the light and dark on days 5, 15, 25, 35, and 45, male guinea pigs mounted and exhibited anogenital investigation of the mother, though appropriately directed mounting occurred infrequently and was not shown by all males. Mothers nipped and kicked advancing males. No ...
Meunier Martine - - 2003
Adult monkeys with late temporal lobe damage are known to touch and mouth objects compulsively, even unknown objects. To determine whether infants with early temporal damage display this symptom as well, 9-month-old rhesus monkeys with neonatal ablations of either the medial temporal lobe or inferior temporal cortex were exposed to ...
Bastian Meredith L - - 2003
We examined the effects of early rearing experience on the development of dominance status in 53 juvenile (age 3) and then in 38 adult (ages 5-8) rhesus macaques. Based on previous research investigating the behavioral outcomes of nursery-rearing, we predicted that mother-reared (MR) monkeys would outrank peer-only reared (PR) monkeys, ...
Mong Jessica A - - 2002
The arcuate nucleus of the hypothalamus is one of several sexually dimorphic hypothalamic nuclei. We have previously demonstrated that astrocytes in the neonatal arcuate nucleus exhibit a marked sexually dimorphic morphology as a result of differential exposure to gonadal steroids by postnatal day (PN) 2, with males having complex stellate ...
Kutsukake Nobuyuki - - 2002
We document here an unusual case of intense aggression against an infant male from another group by chimpanzees (Pan troglodytes schweinfurthii) of the Mahale Mountains National Park, in Tanzania. Adult males of the study group collectively attacked an unknown male infant. Although an unknown female, probably the mother, tried to ...
St Amant Diane C - - 2002
Epidemiological studies suggest H(2)O(2)-producing lactobacilli protect women against gonorrhea. Here we demonstrate that Lactobacillus crispatus and Lactobacillus jensenii, the most common lactobacilli in the female genital tract, inhibit gonococci in both acidic and neutral pH conditions. Inhibition was neutralized by bovine catalase, suggesting that H(2)O(2) is the primary mediator of ...
Batista M - - 2002
The effects of bilateral vasectomy on the seminal characteristics were assessed in six bucks of the Canarian breed. In addition, we tried to establish the effects of vasectomy on the plasmatic concentrations of testosterone and the libido of the bucks. Semen samples were collected once a week from 8 weeks ...
Carrai Valentina - - 2003
In this study we report preliminary data on the consumption of tannin-rich plants by sifakas (Propithecus verreauxi verreauxi) living in the Kirindy forest, western Madagascar. Sifakas spent most of their time feeding on only a few plant species. The tannin intake during the period between the pregnancy and birth season ...
Shintani Norihito - - 2002
Pituitary adenylate cyclase-activating polypeptide (PACAP) is a highly conserved neuropeptide and widely expressed in both brain and peripheral tissues, including several reproductive organs (e.g., testis and ovary). PACAP stimulates syntheses of several sexual hormones and steroids, suggesting it has possible roles in reproductive function. In this study, the role of ...
Cappon G D - - 2002
Peroxisome proliferators are a class of nongenotoxic rodent hepatocarcinogens that cause peroxisome proliferation and liver tumors when administered to rats and mice; but other species, including guinea pigs, dogs, and primates are less sensitive or refractory to the induction of peroxisome proliferation. Therefore, rodent peroxisome proliferators are not believed to ...
Levi Fabio - - 2002
Trends in death certification rates from non-Hodgkin's lymphomas (NHL) were analyzed on the basis of the World Health Organization database over the period 1969-1998. Until the late 1970s, mortality from NHL was similar in the European Union (EU), the USA and Japan, i.e. around 3/100,000 males and 2/100,000 females. Over ...
Bailey Michael T - - 2002
The intestinal microflora of common marmosets and rhesus monkeys were compared by enumerating bacteria from the small and large intestines. Rhesus monkeys had a consistent microflora pattern manifest by higher concentrations of total and Gram-negative aerobic and facultatively anaerobic bacteria, as well as aerobic and anaerobic Lactobacilli, in the large ...
Watts David P - - 2002
Infanticide by males has been recorded in four chimpanzee populations, including that in Kibale National Park, Uganda. Some infanticidal attacks occur during inter-community aggression. The sexual selection hypothesis does not easily explain these attacks because they may not directly increase male mating opportunities. However, females in the attackers' community may ...
Wong Bob B M - - 2002
Certain orchids produce flowers that mimic the sex pheromones and appearance of female insects in order to attract males by sexual deception for the purpose of pollination. In a series of field experiments, we found that the sexually deceptive orchid, Chiloglottis trapeziformis, can have a negative impact on its wasp ...
Pryce Christopher R - - 2002
Rat, monkey, and human infants have evolved to expect certain patterns of care. Spontaneous or experimental deviations of care from the norm result in infant stress responses. Hyperactivity of immature stress systems such as the limbic-hypothalamic-pituitary-adrenal axis and the limbic-sympatho-adrenomedullary axis can alter their subsequent reactivity across the life span.
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