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Ust’-Polui is one of the most extensively studied archaeological sites in the western Siberian Arctic. New radiocarbon (14C) dates for charcoal, faunal remains, bark, hide, and human bone from this site are presented. When modeled, the charcoal dates span from ~260 BC to 140 AD, overlapping with the dendrochronology dates from the site. These dates also overlap with the expected age of the site based on artefact typology. 14C dates on reindeer bone have a slightly younger modeled age range, from ~110 BC to 350 AD. In contrast, dates on the site’s numerous dog remains, and on human and fish bone, all predate these modeled age ranges by over 500 years, despite being from the same deposits. Several sets of paired dates demonstrate significant age differences. Bone dates with lower δ13C values tend to be over 500 years older than those with higher δ13C values. Stable isotope data for the humans, dogs, and other faunal remains are also presented. These data suggest the dogs and the humans were regularly consuming freshwater fish. The dogs were probably fed fish by their human counterparts. Overall, the dog and human dietary patterns at Ust’-Polui created 14C dates biased with major freshwater reservoir effects.
Disorganized attachment is an important early risk factor for socioemotional problems throughout childhood and into adulthood. Prevailing models of the etiology of disorganized attachment emphasize the role of highly dysfunctional parenting, to the exclusion of complex models examining the interplay of child and parental factors. Decades of research have established that extreme child birth weight may have long-term effects on developmental processes. These effects are typically negative, but this is not always the case. Recent studies have also identified the dopamine D4 receptor (DRD4) as a moderator of childrearing effects on the development of disorganized attachment. However, there are inconsistent findings concerning which variant of the polymorphism (seven-repeat long-form allele or non–seven-repeat short-form allele) is most likely to interact with caregiving in predicting disorganized versus organized attachment. In this study, we examined possible two- and three-way interactions and child DRD4 polymorphisms and birth weight and maternal caregiving at age 6 months in longitudinally predicting attachment disorganization at 36 months. Our sample is from the Maternal Adversity, Vulnerability and Neurodevelopment project, a sample of 650 mother–child dyads. Birth weight was cross-referenced with normative data to calculate birth weight percentile. Infant DRD4 was obtained with buccal swabs and categorized according to the presence of the putative allele seven repeat. Macroanalytic and microanalytic measures of maternal behavior were extracted from a videotaped session of 20 min of nonfeeding interaction followed by a 10-min divided attention maternal task at 6 months. Attachment was assessed at 36 months using the Strange Situation procedure, and categorized into disorganized attachment and others. The results indicated that a main effect for DRD4 and a two-way interaction of birth weight and 6-month maternal attention (frequency of maternal looking away behavior) and sensitivity predicted disorganized attachment in robust logistic regression models adjusted for social demographic covariates. Specifically, children in the midrange of birth weight were more likely to develop a disorganized attachment when exposed to less attentive maternal care. However, the association reversed with extreme birth weight (low and high). The DRD4 seven-repeat allele was associated with less disorganized attachment (protective), while non–seven-repeat children were more likely to be classified as disorganized attachment. The implications for understanding inconsistencies in the literature about which DRD4 genotype is the risk direction are also considered. Suggestions for intervention with families with infants at different levels of biological risk and caregiving risk are also discussed.
To investigate: (i) the percentage of the New Zealand (NZ) population reporting fast food/takeaway food and restaurant/café food per day; (ii) examine demographic factors associated with their use; (iii) quantify their contribution to energy intake; and (iv) describe the specific types of foods reported from both sources.
Twenty-four hour diet recalls from the cross-sectional 2008/09 NZ Adult Nutrition Survey were used to identify fast-food and restaurant-food consumers.
Adults aged 15 years and older (n 4721).
Overall 28 % reported consuming at least one fast food and 14 % a restaurant food within the 24 h diet recall. Fast-food consumption was not associated with level of education or an area-based measure of socio-economic status, but a higher education was positively associated with restaurant-food consumption. Individual factors such as ethnicity, household size, age, sex and marital status were found to be important influences on the use of fast food and restaurant food. Fast-food consumption was more prevalent among participants living in urban areas, young adults (19–30 years) and Māori compared with NZ European and Others. The most frequently reported fast foods were bread-based dishes, potatoes (including fries) and non-alcoholic beverages.
Given the high reported consumption of fast food by young adults, health promotion initiatives both to improve the nutritional quality of fast-food menus and to encourage healthier food choices would likely make a large impact on the overall diet quality of this group.
We present femtosecond mid-infrared (mid-IR) studies of the broadband low-energy response of individualized (6,5) and (7,5) single-walled carbon nanotubes. Strong photoinduced absorption is observed in these semiconducting tubes around 200 meV photon energy. The transition energy and broadly sloping spectral shape are characteristic of quasi 1D intra-excitonic transitions between different relative-momentum states. Our result yields a value of the intra-excitonic absorption cross section of σ∥MIR≈4×10-5.
Outlined are two main current research concerns relating to skeletal disorders in poultry: (a) osteoporosis in egg-laying hens; (b) leg problems caused by rapid bone growth in broiler chickens. Surveys indicate that 30% of caged laying hens suffer at least one lifetime fracture (a severe welfare issue). Modern hybrids produce one egg per d for 50 weeks. For this period ‘normal’ bone turnover ceases; only medullary bone (MB) is formed, a woven bone type of limited structural value. MB is resorbed for eggshell formation alongside structural bone, leading to increased fracture risk. Avian osteoporosis is reduced by activity and genetic selection but nutrition is also important. Fluoride and vitamin K are beneficial but the timing of nutritional intervention is important. Ca, inorganic P and vitamin D must be adequate and the form of Ca is critical. Limestone fed as particulates benefits skeletal and eggshell quality. In hens fed particulate limestone compared with flour-fed hens the tibiotarsus breaking strength and radiographic density are increased at 56 weeks of age (P<0·01 and P<0·001 respectively) and the number of tartrate-resistant acid phosphatase-positive stained active osteoclasts (mean number per microscopic field) is decreased (P<0·001). In broiler (meat) chickens selection for rapid growth from approximately 50 g to 3 kg in 42 d has inadvertently produced skeletal disorders such as tibial dyschondroplasia, rickets and associated valgus–varus deformities leading to lameness. The beneficial skeletal effects during growth of increased dietary n-3 PUFA:n-6 PUFA (utilising salmon oil) have been demonstrated. Experiments simulating daylight UVB levels have produced beneficial skeletal effects in Ca- and vitamin D-deficient chicks.
The word ‘transgenic’ refers to an animal or plant that has been transplanted with an exogenous gene. Unlike ICSI and other manipulation techniques on human oocytes and embryos, embryo manipulation in animals, particularly in mice, involves the introduction of a foreign gene to produce either overexpression or disruption of expression of the targeted gene. Transgenic animals are generated to study gene regulation in a tissue-specific (spatial) and developmental stage-specific (temporal) manner. In livestock production, transgenic technology can be applied to develop improved strains and increased disease resistance (Wheeler and Walters, 2001). Transgenic animals can also be utilized as models for various human diseases, wherein the probable causative gene mutation or deletion can be analysed fully throughout development (Campbell, 2002; Petters and Sommer, 2000) and possible therapies can be trialled to alleviate the human disease conditions. Applications of the transgenic mouse include fate mapping of cells during development and acting as markers for unknown regions in the chromosome (Jaenish, 1988). A commonly used technique developed by Gordon et al. (1980) is direct DNA microinjection into the pronuclei of fertilized mouse zygotes. This results in a stable chromosomal integration of the foreign DNA, usually in a head-to-tail array. Since the foreign DNA is present in every cell, including the germ cells, generally integration occurs at the one-cell stage before DNA replication, although later-stage integration can also occur, creating a mosaic mouse. The number of copies integrated varies, and the transgenes are usually integrated in a single chromosomal locus.
Spermatozoa and spermatids can be found within the ejaculate as well as in aspirates and biopsies taken from the epididymis and testis. Therefore, the method of preparation employed is influenced more by the condition of the sample rather than by the maturational stage of the spermatozoa, although some approaches have been developed for the enrichment of specific stages of spermatid. The procedure and requirements for the preparation of oocytes vary only according to whether immature or mature oocytes have been aspirated.
Technical details concerning the routine production, collection and analysis of semen are outside the remit of this book. Therefore knowledge of these aspects is assumed and, in any case, may be gleaned from several already established sources (Fleming et al., 1997; Mortimer, 1994; World Health Organization, 1999).
If no spermatozoa are observed on a Makler chamber (Sefi Medical Instruments Ltd) during semen analysis, then a drop of the ejaculate should be placed under a coverslip on a glass microscope slide as a wet preparation and examined under 200× magnification using a compound microscope with phase-contrast optics. If one or more spermatozoa are then visible, then it should be possible to obtain sufficient spermatazoa for micromanipulation following standard preparation, providing the volume of the ejaculate is adequate (i.e. at least 1 ml). Even if no sperm are visible on a wet preparation, it is still worthwhile centrifuging the ejaculate over a density gradient or in medium (1: 1, v/v) at 500 g for 10 min in order to concentrate whatever spermatozoa may be present at the bottom of the tube.
Eppendorf AG are relative newcomers to the assisted reproduction technology (ART) market. Recognizing the potential for their instruments, they modified their existing Micromanipulator-5171 (a general-purpose micromanipulator, used mainly for the injection of cultured, adherent cells) in 1995 to a version dedicated to the manipulation of cells in suspension, called the TransferMan (see Figure 4.1). The specific requirements of ART forced the evolution of this instrument into the TransferMan NK (see Figure 4.2 and section 4.3) and then the TransferMan NK2 (see Figure 4.3). To complete the micromanipulation workstation, Eppendorf provides manual microinjectors and micropipettes for both the holding and injection sides.
While other manufacturers' devices maintain some sort of mechanical linkage between the controller and the pipette tip, all Eppendorf manipulators rely on microprocessor control, and the TransferMan models are no exception. The movements of the joystick are sensed, encoded digitally, and passed through a microprocessor and on to the headstage. By this means, an intuitive control of the pipette in all three dimensions can be achieved with these instruments in either a dynamic or proportional mode.
In dynamic mode (TransferMan), the joystick is spring-loaded in all three axes so that it returns to its centre position when released. Furthermore, the position of the joystick controls the speed of the micropipette tip: the further the joystick is displaced from the centre, the faster the tip moves.