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Terms modified by New Data Selected AbstractsCOLONY SEX RATIOS IN THE FACULTATIVELY POLYGYNOUS ANT PHEIDOLE PALLIDULA: A REANALYSIS WITH NEW DATAEVOLUTION, Issue 5 2004Ken R. Helms Abstract A recent study by Fournier et al. (2003) provides important new information on sex allocation in the ant Pheidole pallidula, and proposes a new scenario for sex-ratio evolution in P. pallidula and similar species. However, Helms proposed to the authors that two important conclusions of the study were questionable because of potential problems with the analyses. Here we provide new data and a reanalysis that strengthens the conclusion that colony sex ratio is associated with breeding system (i.e., polygyny or monogyny). However, the proposal that colonies shift from monogyny to polygyny when they become larger and more productive is weakened because there is substantial overlap in productivity between monogynous and polygynous colonies. [source] The Determinants of Gender Equity in India: Examining Dyson and Moore's Thesis with New DataPOPULATION AND DEVELOPMENT REVIEW, Issue 2 2004Lupin Rahman In revisiting the influential Dyson and Moore (1983) hypothesis as to why women in South India enjoy relatively more agency than in the North, we conducted an econometric analysis of the determinants of women's mobility and decisionmaking authority. Data for the study come from a household data survey carried out in the Northern state of Uttar Pradesh and in the Southern state of Karnataka in 1995. We find that cross-cousin and uncle-niece marriage is more prevalent in Karnataka as expected. Contrary to Dyson and Moore, however, by 1995 a majority of communities in both North and South practiced village exogamy, and dowries in the two regions were of similar size. Reduced-form, multivariate regressions show that cultural factors affect women's autonomy in ways not earlier predicted. The impact of village exogamy is mixed rather than negative, while that of consanguinity is strongly negative rather than positive as Dyson and Moore surmised. These authors correctly identified the negative effect purdah has on female mobility. Consistent with economic theory, our data show that higher wages for women consistently improve their mobility and authority, while higher male wages decrease them. Improvements in infrastructure,particularly the presence of street lights and schools in the village,are associated with increased women's agency. We conclude, therefore, that economic factors, state action, and restrictions on mobility seem more powerful than kinship structures as explanations of differences in female autonomy between North and South India. [source] NaNO2 + NaNO3 Phase Diagram: New Data from DSC and Raman Spectroscopy.CHEMINFORM, Issue 15 2006Rolf W. Berg Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] A Review of Arthropod Phylogeny: New Data Based on Ribosomal DNA Sequences and Direct Character OptimizationCLADISTICS, Issue 2 2000Gonzalo Giribet Ribosomal gene sequence data are used to explore phylogenetic relationships among higher arthropod groups. Sequences of 139 taxa (23 outgroup and 116 ingroup taxa) representing all extant arthropod "classes" except Remipedia and Cephalocarida are analyzed using direct character optimization exploring six parameter sets. Parameter choice appears to be crucial to phylogenetic inference. The high level of sequence heterogeneity in the 18S rRNA gene (sequence length from 1350 to 2700 bp) makes placement of certain taxa with "unusual" sequences difficult and underscores the necessity of combining ribosomal gene data with other sources of information. Monophyly of Pycnogonida, Chelicerata, Chilopoda, Chilognatha, Malacostraca, Branchiopoda (excluding Daphnia), and Ectognatha are among the higher groups that are supported in most of the analyses. The positions of the Pauropoda, Symphyla, Protura, Collembola, Diplura, Onychophora, Tardigrada, and Daphnia are unstable throughout the parameter space examined. [source] New data for sandwich panels on the correlation between the SBI test method and the room corner reference scenarioFIRE AND MATERIALS, Issue 1 2005Jesper Axelsson Abstract Assessment of the fire behaviour of sandwich panels is continuously under discussion. The fire behaviour of these panels is a combination of material characteristics such as the core material and mechanical behaviour of the panels such as joints, dilations etc. The use of small or intermediate scale tests can be questioned for such types of products. Within the proposed European product standard for sandwich panels (prEN 14509) the intermediate scale test method SBI (EN 13823) has been suggested as the fire test method to certify panels. The standard does, however, use quite an artificial mounting procedure, which does not fully reflect the end-use conditions of the panels. In a previous research project conducted by Nordtest it was shown that the correlation between the SBI test method and both the ISO 9705 and ISO 13784 part 1 was insufficient. The test data produced for the SBI test method, however, did not use the above mentioned mounting technique. In this article new data for a number of products are added to the database using the mounting procedure of the product standard. The data are compared with the previous data and show that the mounting method of the product standard results in slightly more severe conditions but that there are still discrepancies with the full-scale test results. The data also show an unacceptable level of repeatability due to the fact that small dilations result in a wide variation of classification result. The new data together with the old data show once more that it is dangerous to make a fire safety assessment of a sandwich panel based on small or intermediate scale tests. Copyright © 2004 John Wiley & Sons, Ltd. [source] Comparing notes: cancer leaders discuss the latest advancesFUTURE PRESCRIBER, Issue 4 2009Article first published online: 24 DEC 200 New data from different tumour types highlight similarities and differences for specialists, as presented at the Cancer Congress Update meeting held in London, July 2009 [source] Generation and accumulation of oil and condensates in the Wenchang A Sag, western Pearl River Mouth Basin, South China SeaGEOFLUIDS (ELECTRONIC), Issue 4 2009H. J. GAN Abstract The Pearl River Mouth (PRM) Basin is one of four Cenozoic basins in the South China Sea, and the Wenchang A Sag is a secondary depression in the western part of the basin. Both the Wenchang and Enping formations contain good source rocks in the western PRM Basin; however, only the latter has been considered a likely source of the discovered oil and gas. New data from fluid inclusions and the analysis of oil,source rock correlations for the WC10-3 oil and gas pools indicate two stages of petroleum charging, the earlier originating from the Wenchang Formation and the later from the Enping Formation. Kinetics of petroleum generation and structural evolution modeling were employed to further investigate the mechanism of formation of the WC10-3 oil and gas pools. It was shown that the crucial condition for the formation of pools is the time of development of the structural trap. The Wenchang Formation source rocks generated oil from 25 to 14 Ma in the possible source area of the WC10-3 oil and gas pools in the Wenchang A Sag, so that only traps formed earlier than this period could capture oil sourced by the Wenchang Formation. The Enping Formation source rock experienced its oil window from 18 Ma to the present with the main stage of oil generation from 15 to 5 Ma. During this period structural traps in the sag continued to form until movements became weak, so that most pools in the Wenchang A Sag originated from the Enping Formation source rock. The likely dissipation of oil and gas from the earlier stage of charging should be taken into account in assessing the oil potential of the Wenchang A Sag. [source] Age of Irrigation Water in Ground Water from the Eastern Snake River Plain Aquifer, South-Central IdahoGROUND WATER, Issue 2 2000L.N. Plummer Stable isotope data (2H and 18O) were used in conjunction with chlorofluorocarbon (CFC) and tritium/helium-3 (3H/3He) data to determine the fraction and age of irrigation water in ground water mixtures from farmed parts of the Eastern Snake River Plain (ESRP) Aquifer in south-central Idaho. Two groups of waters were recognized: (1) regional background water, unaffected by irrigation and fertilizer application, and (2) mixtures of irrigation water from the Snake River with regional background water. New data are presented comparing CFC and 3H/3He dating of water recharged through deep fractured basalt, and dating of young fractions in ground water mixtures. The 3H/3He ages of irrigation water in most mixtures ranged from about zero to eight years. The CFC ages of irrigation water in mixtures ranged from values near those based on 3H/3He dating to values biased older than the 3H/3He ages by as much as eight to 10 years. Unsaturated zone air had CFC-12 and CFC-113 concentrations that were 60% to 95%, and 50% to 90%, respectively, of modern air concentrations and were consistently contaminated with CFC-11. Irrigation water diverted from the Snake River was contaminated with CFC-11 but near solubility equilibrium with CFC-12 and CFC-113. The dating indicates ground water velocities of 5 to 8 m/d for water along the top of the ESRP Aquifer near the southwestern boundary of the Idaho National Engineering and Environmental Laboratory (INEEL). Many of the regional background waters contain excess terrigenic helium with a 3He/4He isotope ratio of 7 × 10,6 to 11 × 10,6 (R/Ra= 5 to 8) and could not be dated. Ratios of CFC data indicate that some rangeland water may contain as much as 5% to 30% young water (ages of less than or equal to two to 11.5 years) mixed with old regional background water. The relatively low residence times of ground water in irrigated parts of the ESRP Aquifer and the dilution with low-NO3 irrigation water from the Snake River lower the potential for NO3 contamination in agricultural areas. [source] Nanofiltration of plasma-derived biopharmaceutical productsHAEMOPHILIA, Issue 1 2003T. Burnouf Summary. This review presents the current status on the use and benefits of viral removal filtration systems , known as nanofiltration , in the manufacture of plasma-derived coagulation factor concentrates and other biopharmaceutical products from human blood origin. Nanofiltration of plasma products has been implemented at a production scale in the early 1990s to improve margin of viral safety, as a complement to the viral reduction treatments, such as solvent,detergent and heat treatments, already applied for the inactivation of human immunodeficiency virus, hepatitis B and hepatitis C virus. The main reason for the introduction of nanofiltration was the need to improve product safety against non-enveloped viruses and to provide a possible safeguard against new infectious agents potentially entering the human plasma pool. Nanofiltration has gained quick acceptance as it is a relatively simple manufacturing step that consists in filtering protein solution through membranes of a very small pore size (typically 15,40 nm) under conditions that retain viruses by a mechanism largely based on size exclusion. Recent large-scale experience throughout the world has now established that nanofiltration is a robust and reliable viral reduction technique that can be applied to essentially all plasma products. Many of the licensed plasma products are currently nanofiltered. The technology has major advantages as it is flexible and it may combine efficient and largely predictable removal of more than 4 to 6 logs of a wide range of viruses, with an absence of denaturing effect on plasma proteins. Compared with other viral reduction means, nanofiltration may be the only method to date permitting efficient removal of enveloped and non-enveloped viruses under conditions where 90,95% of protein activity is recovered. New data indicate that nanofiltration may also remove prions, opening new perspectives in the development and interest of this technique. Nanofiltration is increasingly becoming a routine step in the manufacture of biopharmaceutical products. [source] The reaction of triphenylarsine oxide with ethyl iodo-acetate leading to triphenyl (carboethoxy)methylarsonium triiodideHETEROATOM CHEMISTRY, Issue 7 2004Boris E. Abalonin New data are presented for some processes accompaning "retro-Arbuzov" reaction of tertiary arsine oxides with halogen-containing reagents. Triphenyl (carboethoxy)methylarsonium triiodide 10a was obtained in the reaction of triphenylarsine oxide 1a with excess of ethyl iodoacetate 2a. The structure of 10a was established by X-ray single crystal diffraction. © 2004 Wiley Periodicals, Inc. Heteroatom Chem 15:482,485, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20050 [source] Annotated chromosome maps for renal disease,HUMAN MUTATION, Issue 3 2009Amy Jayne McKnight Abstract A combination of linkage analyses and association studies are currently employed to promote the identification of genetic factors contributing to inherited renal disease. We have standardized and merged complex genetic data from disparate sources, creating unique chromosomal maps to enhance genetic epidemiological investigations. This database and novel renal maps effectively summarize genomic regions of suggested linkage, association, or chromosomal abnormalities implicated in renal disease. Chromosomal regions associated with potential intermediate clinical phenotypes have been integrated, adding support for particular genomic intervals. More than 500 reports from medical databases, published scientific literature, and the World Wide Web were interrogated for relevant renal-related information. Chromosomal regions highlighted for prioritized investigation of renal complications include 3q13,26, 6q22,27, 10p11,15, 16p11,13, and 18q22. Combined genetic and physical maps are effective tools to organize genetic data for complex diseases. These renal chromosome maps provide insights into renal phenotype-genotype relationships and act as a template for future genetic investigations into complex renal diseases. New data from individual researchers and/or future publications can be readily incorporated to this resource via a user-friendly web-form accessed from the website: www.qub.ac.uk/neph-res/CORGI/index.php. Hum Mutat 0, 1,8, 2008. © 2008 Wiley-Liss, Inc. [source] Divide and conquer: the importance of cell division in regulating B-cell responsesIMMUNOLOGY, Issue 4 2004Stuart G. Tangye Summary Proliferation is an essential characteristic of clonal selection and is required for the expansion of antigen reactive clones leading to the development of antibody of different isotypes and memory cells. New data for mouse and human B cells point to an important role for division in regulating isotype class and in optimizing development of protective immunity by the regulated entry of cells to the plasma cell lineage. [source] Trepanation in the Chachapoya region of northern PerúINTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 1 2007K. C. Nystrom Abstract This paper discusses trepanation frequency data from the Chachapoya region of the northern highlands of Perú. New data from three skeletal samples are presented: Kuelap, Laguna Huayabamba, and Los Pinchudos, as well as isolated crania housed at the Chachapoya Museo Instituto Nacional de Cultura. The vast majority of the trepanations are circular in shape, except for one individual exhibiting as many as three roughly square trepanations. Evidence for healing is prevalent, with examples of both associated periosteal reaction of nearby outer table bone, as well as for healing of the insult itself. Only one case demonstrates a clear association between a traumatic injury and a trepanation event. The purpose or function of the remaining cases of trepanation, however, remains elusive. Copyright © 2006 John Wiley & Sons, Ltd. [source] The importance of local-scale openness within regions dominated by closed woodland,JOURNAL OF QUATERNARY SCIENCE, Issue 6 2007Ralph Fyfe Abstract New and existing pollen data from Wales, UK, are used to assess the level of landscape openness at the regional and local scale. At the regional scale, the existing pollen data support the high-forest model of vegetation structure by 6000 cal. yr. BC prior to any palynological signal for anthropogenic impact in the region. New data from two sites in southwest Wales follow the general regional pattern of early to middle Holocene vegetation succession, but are striking owing to maintenance of high non-arboreal pollen percentages (NAPs) throughout the mid-Holocene. It is argued that these NAPs indicate that a significant degree of openness can be found at the local level (and beyond the confines of the peat-forming site) within regions characterised by closed woodland. It is possible that woodland development in these areas may have been suppressed by reduced drainage, although the role of grazing animals in maintenance of clearings cannot be assessed. Implications for this local degree of openness are discussed, in particular the significance of vegetation heterogeneity at the local scale for the construction of place or locale for prehistoric communities. Copyright © 2006 John Wiley & Sons, Ltd. [source] Oxygen Transport in Silica at High Temperatures: Implications of Oxidation KineticsJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 11 2001C. Eric Ramberg The apparent change in activation energy describing the parabolic rate constant for the passive oxidation of SiC is examined. New data are combined with reevaluated previous results to determine the influences of crystallinity, impurity contamination, and multiple flux mechanisms. The results suggest that the high-temperature transition from interstitial-dominant to network-dominant oxygen transport is a property of amorphous SiO2 scales and does not exist for cristobalite. Highly crystalline scales do not show this transition. Agreement among various studies also suggests that, for high-purity SiO2 scales, there is no difference between the rates of interstitial oxygen transport in amorphous SiO2 and in ,-cristobalite. [source] New data on the distribution and genetic structure of Greek moles of the genus Talpa (Mammalia, Talpidae)JOURNAL OF ZOOLOGICAL SYSTEMATICS AND EVOLUTIONARY RESEARCH, Issue 2 2010G. A. Tryfonopoulos Abstract In this work, we employed molecular markers and confirmed the occurrence of two mole species, Talpa stankovici and Talpa europaea in Greece. For the first species, all analyses revealed three major phylogroups, exhibiting great genetic divergence, possibly due to a vicariant event. This event was probably the Peloponnisos' insulation during the Pliocene and the following sea level fluctuations. A scenario of stable, large-sized populations for a long period rather than rapid growth from small-sized populations or founder events is supported. Additionally, T. stankovici's distribution area is extended to a southernmost limit. For T. europaea there is evidence of low genetic divergence between Greek and Central and North European populations. [source] Economic Growth and Potential Punishment Under DictatorshipKYKLOS INTERNATIONAL REVIEW OF SOCIAL SCIENCES, Issue 2 2007Abel Escribà-Folch SUMMARY This paper explores whether the probability of being punished after losing power leads dictators to restrain their level of predation and, thus, increase economic growth. To do so, a simple model of predatory rule is developed, and the consequences of an increasing probability of punishment after loosing power explored. New data on dictators' post-exit fate have permitted to estimate the predicted probability of punishment taking place by using multinomial logit. Outgoing dictators' strength and the international context are shown to be the main determinants of post-exit scenarios. The probability of punishment is proven to have a positive and significant effect on the rate of growth of GDP under alternative specifications of growth regressions. [source] New data on investigation of novel laser ceramic on the base of cubic scandium sesquioxide: two-band tunable CW generation of Yb3+:Sc2O3 with laser-diode pumping and the dispersion of refractive index in the visible and near-IR of undoped Sc2O3LASER PHYSICS LETTERS, Issue 7 2007K. Takaichi Abstract We report on the first achievement of tunable twoband "one-micron" CW oscillation in the 2F5/2 , 2F7/2 channel of Yb3+ activator ions in Sc2O3 ceramics with CW laserdiode pumping, as well as on results of precise measurement of the refractive index and its dispersion in spectral range 0.365 , 2.325 ,m and full transmission spectra of undoped Sc2O3 ceramics fabricated by the VSN method. (© 2007 by Astro Ltd., Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA) [source] The role of noncredit courses in serving nontraditional learnersNEW DIRECTIONS FOR HIGHER EDUCATION, Issue 129 2005John Milam New data on noncredit course offerings at colleges and universities help to generate a statistical portrait of these increasingly important programs. [source] Leptin and Insulin Action in the Central Nervous SystemNUTRITION REVIEWS, Issue 2002Daniel Porte Jr M.D. Body adiposity is known to be carefully regulated and to remain relatively stable for long periods of time in most mammalian species. This review summarizes old and recent data implicating insulin and leptin as key circulating signals to the central nervous system, particularly the ventral hypothalamus, in communicating thesizeand thedistribution of body fat stores. This input ultimately alters food intake and energy expenditure to maintain constancy of the adipose depot. The key primary neurons in the arcuate nucleus containing NPY/AgRP and POMC/CART appear be critical constituents of the CNS regulating system, and are shown to contribute to anabolic and catabolic signaling systems to complete the feedback loop. New data to indicate shared intracellular signaling from leptin and insulin is provided. The satiety system for meals, consisting of neural afferents to the hind-brain from the gastrointestinal tract, is described and its effectiveness is shown to vary with the strength of the insulin and leptin signals. This provides anefferent mechanism that plays a key role in a complex feedback system that allows intermittent meals to vary from day to day, but provides appropriate long-term adjustment to need. Recently described contributions of this system to obesity are described and potential therapeutic implications are discussed. [source] Radiation and breast carcinogenesis,PEDIATRIC BLOOD & CANCER, Issue 5 2001John D. Boice Jr. Abstract With the possible exception of radiation-induced leukemia, more is known about radiation-induced breast cancer than any other malignancy [1, 2]. Fourteen cohort studies have provided quantitative information on the level of risk following a wide range of doses in different populations around the world. Comprehensive studies have been conducted in Canada, Germany, Japan, Sweden and other Nordic countries, the United Kingdom, and the USA (Table I). Key features are the linearity in the dose response (i.e., a straight line adequately fits the observed data), and the effect modification of age at exposure (i.e., risk is inversely related to exposure age and exposures past the menopausal ages appear to carry a very low risk); and the minimal effect of fractionating dose on subsequent risk [3]. A recent combined analysis of almost 78,000 women and 1,500 breast cancer cases from eight cohorts confirmed the downturn in risk at the highest dose levels (related in part to the killing of cells rather than transformation) and that fractionation of dose has little influence on risk, at least on an absolute scale [4]. It is not known whether persons predisposed to cancer are at enhanced risk of radiation-induced breast cancer from low-dose exposures, although this seems unlikely [5]. New data on the effects of high doses following childhood exposures will be forthcoming from long-term studies of the survivors of childhood cancer (6,8). Med. Pediatr. Oncol. 36:508,513, 2001. © 2001 Wiley-Liss, Inc. [source] New data on the late Neandertals: Direct dating of the Belgian Spy fossilsAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 4 2009Patrick Semal Abstract In Eurasia, the period between 40,000 and 30,000 BP saw the replacement of Neandertals by anatomically modern humans (AMH) during and after the Middle to Upper Paleolithic transition. The human fossil record for this period is very poorly defined with no overlap between Neandertals and AMH on the basis of direct dates. Four new 14C dates were obtained on the two adult Neandertals from Spy (Belgium). The results show that Neandertals survived to at least ,36,000 BP in Belgium and that the Spy fossils may be associated to the Lincombian,Ranisian,Jerzmanowician, a transitional techno-complex defined in northwest Europe and recognized in the Spy collections. The new data suggest that hypotheses other than Neandertal acculturation by AMH may be considered in this part of Europe. Am J Phys Anthropol, 2009. © 2008 Wiley-Liss, Inc. [source] New Developments in the Pharmacotherapy of Alcohol DependenceTHE AMERICAN JOURNAL ON ADDICTIONS, Issue 2001Hugh Myrick M.D. Neuroscientific underpinnings and pharmacotherapeutic treatments of sub-stance use disorders are rapidly developing areas of study. In particular, there have been exciting new developments in our understanding of the involvement of excitatory amino acid neurotransmitter systems and the opiate and serotonin systems in the pathophysiology of alcohol withdrawal, alcohol dependence, and in subtypes of individuals with alcoholism. In this article, new developments in the pharmacotherapy of alcohol dependence will be reviewed. In particular, the use of anticonvulsants in alcohol withdrawal and protracted abstinence syndromes will be discussed. New data on opiate antagonists and acamprosate, an agent that exerts actions through excitatory amino acid systems in relapse prevention, will be reviewed. Finally, there will be a review of new data concerning the use of serotonin reuptake inhibitors in subtypes of alcoholism and the use of combination pharmacotherapy. [source] Reproductive ageing in women,THE JOURNAL OF PATHOLOGY, Issue 2 2007O Djahanbakhch Abstract The traditional view in respect to female reproduction is that the number of oocytes at birth is fixed and continuously declines towards the point when no more oocytes are available after menopause. In this review we briefly discuss the embryonic development of female germ cells and ovarian follicles. The ontogeny of the hypothalamic-pituitary-gonadal axis is then discussed, with a focus on pubertal transition and normal ovulatory menstrual cycles during female adult life. Biochemical markers of menopausal transition are briefly examined. We also examine the effects of age on female fertility, the contribution of chromosomal abnormalities of the oocyte to the observed decline in female fertility with age and the possible biological basis for the occurrence of such abnormalities. Finally, we consider the effects of maternal age on obstetric complications and perinatal outcome. New data that have the potential to revolutionize our understanding of mammalian oogenesis and follicular formation, and of the female reproductive ageing process, are also briefly considered. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [source] Allograft Fibrosis,Unmasking the Players at the DanceAMERICAN JOURNAL OF TRANSPLANTATION, Issue 2 2010R. B. Mannon New data suggest that the pleiotropic cytokine interleukin-6 may be a key contributor to allograft fibrosis through a complex interaction with connective tissue growth factor (CTGF), a downstream effector of TGF-beta. See article by Booth et al on page 220. [source] "Specialized" Production in Archaeological Contexts: Rethinking Specialization, the Social Value of Products, and the Practice of ProductionARCHEOLOGICAL PAPERS OF THE AMERICAN ANTHROPOLOGICAL ASSOCIATION, Issue 1 2007Rowan K. Flad The contributions to this volume are introduced via a critical review of terms and concepts used in craft production studies today. Recent detailed contextual and technological analyses of artifacts from all aspects of complex societies have revealed interesting patterns that are difficult to conceptualize using a purely economic framework. Furthermore, interest in practice theory, and sociocultural theory in general, has shifted some foci of archaeological investigation toward the social aspects of production and specialization. New data, methods, and theories require a rethinking of what is meant by specialized production, and this chapter represents an introduction to this endeavor. [source] Present-day stresses in Brunei, NW Borneo: superposition of deltaic and active margin tectonicsBASIN RESEARCH, Issue 2 2010R. C. King ABSTRACT The Baram Delta System, Brunei, NW Borneo, is a Tertiary delta system located on an active continental margin. Delta top regions in many Tertiary delta systems (e.g. Niger Delta) are thought to exhibit a normal-fault stress regime and margin-parallel maximum horizontal stress orientations. However, unlike in passive margin Tertiary delta systems, two present-day stress provinces have been previously identified across the Baram Delta System: an inner shelf inverted province with a margin-normal (NW,SE) maximum horizontal stress orientation and an outer shelf extension province with a margin-parallel (NE,SW) maximum horizontal stress orientation. Before this study, there were few data constraining the inverted province other than in the vicinity of the Champion Fields. New data from 12 petroleum wells in the western inner shelf and onshore west Brunei presented herein confirm the margin-normal maximum horizontal stress orientations of the inverted province. A total of 117 borehole breakouts, all documented in shale units, and one drilling-induced tensile fracture (in a sandstone interval) reveal a mean maximum horizontal stress orientation of 117 with a standard deviation of 19°. This orientation is consistent with contemporary margin-normal maximum horizontal stress orientations of the inverted province described previously in the vicinity of the Champion Fields that have been linked to basement tectonics of the Crocker,Rajang accretionary complex and associated active margin. However, stress magnitudes calculated using data from these 12 petroleum wells indicate a borderline strike,slip fault to normal fault stress regime for the present day; combined with the absence of seismicity, this suggests that the studied part of the NW Borneo continental margin is currently tectonically quiescent. [source] Stratigraphic evolution of the Triassic,Jurassic succession in the Western Southern Alps (Italy): the record of the two-stage rifting on the distal passive margin of AdriaBASIN RESEARCH, Issue 3 2009Fabrizio Berra ABSTRACT The Triassic,Lower Jurassic succession of the Southern Alps is characterized by rapid thickness changes, from an average of about 5000 m east of Lago Maggiore to about 500 m in the Western Southern Alps. The stratigraphy reflects the Triassic evolution of the Tethyan Gulf and the Early Jurassic rifting responsible for the Middle Jurassic break-up of Adria from Europe. The succession of the Western Southern Alps starts with Lower Permian volcanics directly covered by Anisian sandstones. The top of the overlying Ladinian dolostones (300 m) records subaerial exposure and karstification. Locally (Gozzano), Upper Sinemurian sediments cover the Permian volcanics, documenting pre-Sinemurian erosion. New biostratigraphic data indicate a latest Pliensbachian,Toarcian age for the Jurassic synrift deposits that unconformably cover Ladinian or Sinemurian sediments. Therefore, in the Western Southern Alps, the major rifting stage that directly evolved into the opening of the Penninic Ocean began in the latest Pliensbachian,Toarcian. New data allowed us to refine the evolution of the two previously recognized Jurassic extensional events in the Southern Alps. The youngest extensional event (Western Southern Alps) occurred as tectonic activity decreased in the Lombardy Basin. During the Sinemurian the Gozzano high represents the western shoulder of a rift basin located to the east (Lombardy). This evolution documents a transition from diffuse early rifting (Late Hettangian,Sinemurian), controlled by older discontinuities, to rifting focused along a rift valley close to the Pliensbachian,Toarcian boundary. This younger rift bridges the gap between the Hettangian,Sinemurian diffuse rifting and the Callovian,Bathonian break-up. The late Pliensbachian,Toarcian rift, which eventually lead to continental break-up, is interpreted as the major extensional episode in the evolution of the passive margin of Adria. The transition from diffuse to focused extension in the Southern Alps is comparable to the evolution of the Central Austroalpine during the Early Jurassic and of the Central and Northern Atlantic margins. [source] Sexual devolution in plants: apomixis uncloaked?BIOESSAYS, Issue 9 2008Richard D. Noyes There are a growing number of examples where naturally occurring mutations disrupt an established physiological or developmental pathway to yield a new condition that is evolutionary favored. Asexual reproduction by seed in plants, or apomixis, occurs in a diversity of taxa and has evolved from sexual ancestors. One form of apomixis, diplospory, is a multi-step development process that is initiated when meiosis is altered to produce an unreduced rather than a reduced egg cell. Subsequent parthenogenetic development of the unreduced egg yields genetically maternal progeny. While it has long been apparent from cytological data that meiosis in apomicts was malfunctional or completely bypassed, the genetic basis of the phenomenon has been a long-standing mystery. New data from genetic analysis of Arabidopsis mutants1 in combination with more sophisticated molecular understanding of meiosis in plants indicate that a weak mutation of the gene SWI, called DYAD, interferes with sister chromatid cohesion in meiosis I, causes synapsis to fail in female meiosis and yields two unreduced cells. The new work shows that a low percentage of DYAD ovules produce functional unreduced egg cells (2n) that can be fertilized by haploid pollen (1n) to give rise to triploid (3n) progeny. While the DYAD mutants differ in some aspects from naturally occurring apomicts, the work establishes that mutation to a single gene can effectively initiate apomictic development and, furthermore, focuses efforts to isolate apomixis genes on a narrowed set of developmental events. Profitable manipulation of meiosis and recombination in agronomically important crops may be on the horizon. BioEssays 30:798,801, 2008. © 2008 Wiley Periodicals, Inc. [source] Single median maxillary central incisor: New data and mutation reviewBIRTH DEFECTS RESEARCH, Issue 8 2007Kênia B. El-Jaick Abstract BACKGROUND: Single median maxillary central incisor (SMMCI) is a rare anomaly that may occur alone or associated with other conditions, frequently as part of the holoprosencephaly (HPE) spectrum. However, it has been suggested that SMMCI alone, or associated with some midline defects, may be considered a different entity from HPE (OMIM: 147250). Families with SMMCI, without HPE cases, are difficult to counsel for the risk of HPE in future generations because the same midline defects described as part of the "SMMCI syndrome" can also be part of the HPE spectrum. METHODS: We screened five cases of SMMCI for mutations in three HPE genes, SHH, TGIF, and SIX3. RESULTS: A missense mutation c.686C>T was found in the gene SIX3 of one patient, which did not differ from the accepted 20% of known HPE gene mutations among all HPE cases. Our results and an extensive literature review of gene mutations in patients with SMMCI showed that 27/28 of them were in HPE genes: SHH (n = 21), SIX3 (n = 3), TGIF (n = 1), GLI2 (n = 1), and PTCH (n = 1), and only one in the SALL4 gene. CONCLUSIONS: The clinical findings in patients with SMMCI without HPE in families with mutations in HPE genes cannot be distinguished from the findings reported in the SMMCI syndrome. Therefore, persons with SMMCI and their relatives should be carefully investigated for related midline disorders, especially of the HPE spectrum, and all known HPE genes screened. Birth Defects Research (Part A), 2007. © 2007 Wiley-Liss, Inc. [source] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||