bluuebunny/crossref_metadata_2025 huggingface dataset:
client satisfaction with abortion care in three russian cities
Authors: oliveras elizabeth , larsen ulla , david patricia h.
Published: August 2005

this paper explores client satisfaction with abortion care, looking at overall satisfaction and satisfaction with hygiene, comfort and courtesy. the analysis aimed to determine whether client satisfaction was related to the characteristics of the client, in order to guide quality improvement efforts. the analysis is a secondary analysis of data collected in a survey of 489 abortion clients who attended a limited number of hospitals in three cities in russia. the data were analysed using logistic regression. client characteristics, in general, did not affect overall satisfaction though there were significant differences in overall satisfaction for unmarried versus married women (or=0·29, ci=0·13, 0·63). similarly, most characteristics of the abortion visit were not related to client satisfaction, although women who were awake for the procedure were less likely to be satisfied (or=0·37, ci=0·16, 0·89). information provided to abortion clients about self-care was the most important predictor of overall satisfaction for abortion clients (or=3·55, ci=1·64, 7·69). this suggests that improving the information provided to clients, through training providers and other staff, is important in these settings.
human sexual dimorphism in size may be triggered by environmental cues
Authors: kanazawa satoshi , novak deanna l.
Published: August 2005

evolutionary biologists mostly assume that polygyny increases sexual dimorphism in size because, under polygyny, larger males monopolize mating opportunities and pass on their ‘large male’ genes to their sons. available data on parent–child correlations in height among humans (homo sapiens) do not support the crucial assumption that height is transmitted along sex lines. this paper instead suggests that human sexual dimorphism in size emerged, not because men got taller, but because women got shorter by undergoing early menarche in response to polygyny. it further speculates that, rather than genetically transmitted, the sexual dimorphism may emerge anew in each generation in response to the degree of polygyny in society. the analysis of comparative data supports the prediction that polygyny reduces women’s height, but has no effect on men’s, and is consistent with the speculation that the origin of human sexual dimorphism in size may be cultural, not genetic.
Autocrine prolactin as a promotor of mammary tumour growth
Authors: Manhes Caroline , Goffin Vincent , Kelly Paul A , Touraine Philippe
Published: August 2005

Prolactin (PRL) plays a key role in normal growth, development and differentiation of the mammary gland. Indeed, strong evidence suggests that the development of alveolar cells requires not only oestradiol and progesterone, but also PRL. In vitro, PRL has mitogenic activity on normal mouse mammary epithelial cells (reviewed in Das & Vonderhaar, 1997). In vivo, PRL also seems to be involved in such proliferative activity, although it is more difficult to distinguish the role of PRL from the influence of the hormonal milieu (Das & Vonderhaar, 1997). This physiological role of PRL in lobular development of the mammary gland is supported by results obtained from mice deficient for PRL (Horseman et al. 1997) or for its receptor (PRLR) (Ormandy et al. 1997). Although the infertility of females homozygous for the deletion of the PRLR gene (PRLR−/−) can be partially reversed by restoring progesterone levels close to normal, their mammary gland fails to differentiate during pregnancy, leading to lactation failure (Binart et al. 2000). In addition, heterozygous mice (PRLR+/−), who have half normal receptor levels, show impaired mammary gland development and fail to lactate following their first pregnancy, clearly indicating that signals mediated by the PRL/PRLR interaction have to achieve a certain level to permit mammary gland differentiation and lactation (Kelly et al. 2002). Since the pioneering work of Topper (Topper, 1970), who observed that PRL was necessary to induce casein synthesis, our understanding of the mechanism of such induction has greatly expanded. PRL appears to be the primary hormone involved in this activity, although other hormones such as insulin and glucocorticoids are also required for lactation.
Role of progesterone metabolites in mammary cancer
Authors: Wiebe John P
Published: August 2005

Among the species investigated, the rate of spontaneous cancers of mammary glands is highest in humans and dogs (Hamilton, 1974; Owen, 1979). In addition, spontaneous mammary tumours are known to occur in strains of mice (Webster & Muller, 1994), rats (Russo et al. 1990; Sukumar, 1995) and cats (Hamilton, 1974; Kessler & von Bombard, 1997). Although both oestrogen and progesterone are known to be involved in normal mammary development as well as in the proliferative changes that occur during the oestrous or menstrual cycle, pregnancy and lactation (Going et al. 1988), only the role of oestradiol has been extensively investigated. The role of progesterone in mammary cancer is not understood and, although progesterone metabolism is known to occur in mammary tissue, the potential autocrine/paracrine role of the in situ metabolites has only recently begun to be explored in human breast tissues and cell lines (Wiebe et al. 2000).
Improved detection of Mycobacterium paratuberculosis in milk
Authors: D'Haese Eva , Dumon Iris , Werbrouck Hadewig , De Jonghe Valerie , Herman Lieve
Published: August 2005

At present there is no rapid microbiological method for the detection of viable Mycobacterium paratuberculosis in milk. By combining an extensive milk sample pretreatment with solid phase cytometry as the detection technique we were able to demonstrate viable mycobacterial cells in 50 ml of artificially contaminated pasteurized milk in less than one working day.
Breast cancer and sphingolipid signalling
Authors: Signorelli Paola , Ghidoni Riccardo
Published: August 2005

Cancer develops from overlapping events that tend to deregulate the metabolism and unbalance the homeostasis of cells. Sphingolipids, major components of biological membranes, are also mediators of intracellular signalling. Their metabolism can be influenced by diverse stimuli and the accumulation or deficiency of intermediates may trigger proliferation and/or impair the ability of damaged cells to undergo apoptosis. Many sphingolipid-regulated functions are implicated in tumour initiation, promotion, progression and responsiveness to chemotherapy. In this review, evidence of the alteration of sphingolipids metabolism and signalling will be discussed in breast cancer prevention and therapy.
Complex mammary tumours in the female dog: a review
Authors: Hellmén Eva
Published: August 2005

Spontaneous mammary tumours are most frequently seen (apart from rodents) in women, female dogs and cats. The mammary gland is the most commonly affected organ for tumours in women and in female dogs. The mammary gland has a similar histology in the different species whereas the number of glands differs as well as the number of interlobular ducts that reach the nipple/teat. The parenchymatous tissue is composed of alveoli that turn into interlobular ducts. The whole ductal tree is outlined by a two-layered epithelium with the luminal epithelial cells adjacent to the lumen and the more sparse myoepithelial cells peripherally located to these. Different proteins such as growth factors regulate the mammary gland, as they do for all tissues in the body. In addition, sex hormones regulate the biology of the mammary gland. Oestrogen has the most pronounced effect on duct growth whereas progesterone promotes growth of the alveoli.
The lactation cycle of the fur seal
Authors: Sharp Julie A , Cane Kylie , Arnould John PY , Nicholas Kevin R
Published: August 2005

The fur seal is a mammal with an unusual ability to turn its milk production on and off without significantly altering the gross morphology of the mammary gland. This atypical lactation cycle is due to the fact that maternal foraging and infant nursing are spatially and temporally separate (Bonner, 1984). Maternal care involves the suckling of offspring over a period of at least 4 months, but lactation can extend to more than 12 months. Following a perinatal fast of approximately 1 week, females depart the breeding colony to forage at sea and, for the remainder of lactation, alternate between short periods ashore suckling their young with longer periods of up to 4 weeks foraging at sea. Whilst foraging at sea, milk production in the fur seal mammary gland either ceases or is reduced (Arnould & Boyd, 1995b).
Feline mammary tumours in comparative oncology
Authors: Zappulli Valentina , De Zan Gabrita , Cardazzo Barbara , Bargelloni Luca , Castagnaro Massimo
Published: August 2005

Naturally occurring tumours in domestic animals have been recognized as an interesting opportunity for comparative oncology (MacEwen, 1990; Vail & MacEwen, 2000). Cancer is the second most frequent cause of death in humans and the first one in dogs and cats (Jemal et al. 2003). The age-adjusted overall cancer incidence per 100000 individuals per year is comparable in humans and domestic animals, being approximately 300 in humans, 381 in dogs and 264 in cats (Vail & MacEwen, 2000). When analysing the incidence by site, breast cancer is the most frequent (32%) in women, the first of all neoplasia (52%) occurring in bitches and the third (17%) in queens after lymphohaemopoietic and skin tumours (Hayes et al. 1981; Hayes & Mooney, 1985; MacEwen, 1990; MacEwen & Withrow, 1996; Jemal et al. 2003). Several other aspects contribute to the value of domestic animals as models for human cancers (MacEwen, 1990; Vail & MacEwen, 2000). Tumours occur spontaneously in companion animals that share a similar environment with humans and therefore might be exposed to similar risk factors. The high incidence of some tumour types offers large population samples. The shorter overall lifespan of domestic animals associated with a more rapid progression of cancer allows adequate comparison of response time with humans. Biological, anatomical, histopathological, genetic, and molecular similarities between some animal and human tumours are also well established (Hansen & Khanna, 2004). Finally, testing novel therapies is more ethically acceptable when treating spontaneous diseases in companion animals rather than experimentally induced pathologies in animal models. At the same time, there is an increasing interest of owners towards the use of the most advanced therapeutic tools for companion animals despite the higher economic costs associated with these therapies.
Tumor necrosis factor receptor-mediated apoptosis inTrichinella spiralis-infected muscle cells
Authors: WU Z. , NAGANO I. , BOONMARS T. , TAKAHASHI Y.
Published: August 2005

In order to reveal the mechanisms underlying nurse cell formation duringTrichinella spiralisinfection, the expression of the factors of tumor necrosis factor-alpha (TNF-α)/TNF receptor 1 (TNFR-1) signalling pathway mediating apoptosis was investigated. The analysed factors included TNF-α, TNFR-1, TNF receptor-associated death-domain (TRADD), caspase 3, caspase 8, TNF receptor associated factor-2 (TRAF2) and receptor interactive protein (RIP), all of which are involved in the TNF-α/TNFR-1 signalling pathway-mediated apoptosis. The quantitative RT-PCR indicated that the infected muscle tissues up-regulate the expression of pro-apoptosis genes (TNF-α, TNFR-1 and TRADD, caspase 3 and caspase 8), and anti-apoptosis genes (TRAF2 and RIP) at the beginning of cyst formation. The expression returned to the normal level after cyst formation. The quantitative RT-PCR analysis of mRNA from tissue samples isolated by laser capture micro-dissection confirmed that the up-regulation of these genes was restricted in infected muscle cells, was not in the inflammation cells around infected muscle cells nor in normal muscle cells. Thein situlocalization study of pro-apoptosis (TRADD, caspase 3) and anti-apoptosis gene products (TRAF2) indicated that these were expressed in the basophilic cytoplasm (infected muscle cell origin) of the nurse cells. Thus the present study suggests that the TNF-α/TNFR-1 signalling pathway is involved in nurse cell formation.
The effect of non-immune stresses on the development ofStrongyloides ratti
Authors: CROOK M. , VINEY M. E.
Published: August 2005

Strongyloides rattiis a parasitic nematode of rats. The host immune response againstS. rattiaffects the development of its free-living generation, favouring the development of free-living adult males and females at the expense of directly developing, infective 3rd-stage larvae. However, how the host immune response brings about these developmental effects is not clear. To begin to investigate this, we have determined the effect of non-immune stresses on the development ofS. ratti. These non-immune stresses were subcurative doses of the anthelmintic drugs Ivermectin, Dithiazanine iodide and Thiabendazole, and infection of a non-natural host, the mouse. These treatments produced the opposite developmental outcome to that of the host immune response. Thus, in infections treated with subcurative doses of Ivermectin, Dithiazanine iodide and in infections of a non-natural host, the sex ratio of developing larvae became more female-biased and the proportion of female larvae that developed into free-living adult females decreased. This suggests that the mechanism by which the host immune response and these non-immune stresses affectS. rattidevelopment differs.
Microphallids inGammarus insensibilisStock, 1966 from a Black Sea lagoon: manipulation hypothesis going East?
Authors: KOSTADINOVA A. , MAVRODIEVA R. S.
Published: August 2005

Patterns of parasite site selection, variation in infection parameters and interspecific associations are examined in the light of new field data on larval microphallids inGammarus insensibilisfrom a Black Sea lagoon. These patterns are discussed in relation to the predictions for the manipulative effect ofMicrophallus papillorobustusand its relationships with the other microphallid species based on studies on the French Mediterranean coast. Four species were recovered:Maritrema subdolum,Microphallus hoffmanni,M. papillorobustusandLevinseniella propinqua. The latter two were located in both corporal and cephalic segments, but the selection of brain appeared stronger forL. propinqua. M. subdolumwas the first colonizer of amphipod population recruits, and unequivocally the dominant species in the lagoon. There was a significant positive relationship between the parasite load of all 4 species. Concurrent infections were exceedingly frequent, and no departures from random association were detected. We found no evidence that the cerebral metacercariae ofM. papillorobustusconsistently predict the parasite load of any of the other species in the system and identify sources for heterogeneity that may account for the differences between the Black Sea and the Mediterranean system: habitat heterogeneity, bird diversity and host-parasite systems used to infer relationships between microphallids.
Population biology of multispecies helminth infection: interspecific interactions and parasite distribution
Authors: BOTTOMLEY C. , ISHAM V. , BASÁÑEZ M.-G.
Published: August 2005

Despite evidence for the existence of interspecific interactions between helminth species, there has been no theoretical exploration of their effect on the distribution of the parasite species in a host population. We use a deterministic model for the accumulation and loss of adult worms of 2 interacting helminth species to motivate an individual-based stochastic model. The mean worm burden and variance[ratio ]mean ratio (VMR) of each species, and the correlation between the two species are used to describe the distribution within different host age classes. We find that interspecific interactions can produce convex age-intensity profiles and will impact the level of aggregation (as measured by the VMR). In the absence of correlated exposure, the correlation in older age classes may be close to zero when either intra- or interspecific synergistic effects are strong. We therefore suggest examining the correlation between species in young hosts as a possible means of identifying interspecific interaction. The presence of correlation between the rates of exposure makes the interpretation of correlations between species more difficult. Finally we show that in the absence of interaction, strong positive correlations are generated by averaging across most age classes.
Microphallids in Gammarus insensibilis Stock, 1966 from a Black Sea lagoon: host response to infection
Authors: KOSTADINOVA A. , MAVRODIEVA R. S.
Published: August 2005

We examined the patterns of parasite melanization in Gammarus insensibilis using data on microphallids from Pomorie Lagoon (Black Sea) in the light of 3 predictions associated with host survival: (i) hosts invest more in defence in an environment where the likelihood for infection is higher; (ii) multiple immune challenges exhaust host reserves and result in decreased melanization rates in older hosts; (iii) host immune response is directed against the cerebral metacercariae of Microphallus papillorobustus that alter amphipod behaviour and are most detrimental to the host. G. insensibilis was capable of melanizing the metacercariae of all four species of trematodes found to be hosted by the amphipods. The frequency of melanization and mean abundance of melanized metacercariae were substantially higher than those observed in the same amphipod-gammarid system on the French Mediterranean coast. However, the rate of melanization was low and showed a significant decrease with amphipod size. Although the 4 species were differentially melanized, the host response was largely directed against Microphallus hoffmanni and M. subdolum. We suggest that (i) the lower melanization efficiency with age is due to the mode of infection, probably leading to loss of haemolymph and monopolization of the defence resources for wound healing and (ii) in the French system, host response focuses on the most prevalent and abundant species.
The role of sex steroids in the complex physiology of the host-parasite relationship: the case of the larval cestode of Taenia crassiceps
Authors: MORALES-MONTOR J. , LARRALDE C.
Published: August 2005

Sex steroids play a significant role in regulating the parasite load in experimental intraperitoneal Taenia crassiceps cysticercosis of male and female Balbc/anN mice. Briefly, oestrogens increase parasite loads and androgens decrease them (1) by acting directly on the parasite, favouring or hindering its reproduction, respectively, and (2) by biasing the hosts' immune response towards a parasite-permissive Th2 or a parasite-restrictive Th1 response. The infected male host also undergoes drastic endocrinological and behavioural changes that may impinge upon the course of infection, and the host's mating behaviour and its exposure to predators. In addition, at different times of infection, significant changes occur in the expression of c-fos in the host's hyppocampus, hypothalamus and preoptic area. Thus, the host's brain seems to sense and/or react to intraperitoneal infection. The physiological domains of the network affected by the infection, which classically included the hypothalamus-pituitary-axis and the immune system, must now incorporate the host's sexual hormones and other areas of the brain. The network's complex circuitry and functions may help understand some basic questions of parasitology (i.e. the hosts' sexual dimorphism in parasite infections, host-parasite specificity, heterogeneity in the course and outcome of infections at different stages of parasite and host development). The plurality of elements and the complexity of the network that regulates the host-parasite relationship also point to additional strategies for the treatment and control of infections.
Medical Entomology for Students 3rd Edn. By M. W. Service, pp. 285. Cambridge University Press UK, 2004. ISBN 0 521 54775 X. £27.00. (US $48.00)
Authors: WARD RICHARD D.
Published: August 2005

Four years on from the 2nd Edition of this useful introductory text this book remains good value at a modest price rise of only £5.00. In twenty chapters Professor Service follows his well-worked and consistent pattern in each chapter by describing the morphology of each group of vectors, followed by life-cycle, medical importance and control. The further reading information provided at the end of each chapter has been updated wherever relevant. In addition, as an aide-mémoire to revising, certain key words now appear in bold. In many groups, new information is provided on the numbers of species now described. In the case of mosquitoes this is now 3300, an increase of 100 and there are now 4 further genera including Ochlerotatus, a previous subgenus of Aedes. Outstanding developments in control include the innovative development of manufactured bed nets that are impregnated with synthetic pyrethroids, which are designed to release the active molecule over periods as long as four years. Mike Service is, however, cautious, and warns that despite our great hopes for this new development, the incidence of resistance to pyrethroids is a realistic potential threat to its success. In similar vein it is noted that mosquitoes in the laboratory have been observed to develop resistance to the bacterial insecticides Bacillus thuringiensis and B. sphaericus. This has not as yet proved to be a problem in the field with mosquitoes, but experience with agricultural pests, such as the diamondback moth, indicates the need for vigilance.
The Trypanosomiases (ed. Maudlin, I., Holmes, P. H. & Miles, M. A.), pp. 624. International CABI Publishing, UK, 2004. ISBN 0 85199 475 X. £99.50 (US$185.00).
Authors: VICKERMAN KEITH
Published: August 2005

Back in the early 1960s, when the curtain was falling on British colonial administration in Africa, the newly-created Ministry of Overseas Development decided to gather together for posterity the expertise and experience of authorities on tsetse and trypanosomiasis control. Weighing in at three and a half pounds, the resulting publication, ‘The African Trypanosomiases’ edited by Colonel Hugh Mulligan and published in 1969, has since been a baseline not only for investigators in the field but also for pure scientists working on related problems at the laboratory bench. The editors of the present volume were inspired by the enormous progress made in trypanosomiasis research over the last thirty years to produce ‘an update of Mulligan’ – so, how do the two books compare? Well, amazingly, their weights are exactly the same – but content and coverage are, as might be expected, very different.
A NEW SPECIES OF CYNOGLOSSUM (BORAGINACEAE–CYNOGLOSSEAE) FROM EASTERN TURKEY
Authors: SUTORÝ K.
Published: August 2005

The new species Cynoglossum vanense (Boraginaceae) from around Lake Van and Hakkâri in eastern Turkey is described and illustrated. Its larger nutlets with relatively long glochids separate it from other known species in subgenus Cynoglossum.
OLD WORLD GESNERIACEAE IX: MISCELLANEOUS SPECIES OF CYRTANDRA IN BORNEO
Authors: HILLIARD O. M.
Published: August 2005

New descriptions, followed by discussion, are given for the following species described by Kraenzlin: Cyrtandra cerea, C. foveolata, C. megalocrater, C. prostrata, C. quinquenotata, C. robusta, C. strictipes; C. populifolia, as enumerated by Kraenzlin, is a misdetermination. Cyrtandra paxiana and C. serratobracteata are also re-described, and one recently discovered new species, C. crockeriana, is established.
OLD WORLD GESNERIACEAE X: BORNEAN SPECIES OF CYRTANDRA ALLIED TO C. PHOENICOLASIA
Authors: HILLIARD O. M. , BURTT B. L.
Published: August 2005

Cyrtandra phoenicolasia, C. hottae and five new species constitute a group distinguished by a suite of characters including setose vegetative parts, deeply divided calyx, small white corolla marked on the lower lip with yellow to brown, unilateral disc, ovary constricted at base, and fruit small. All species are fully described and an identification key provided.
THREE NEW SPECIES AND A NEW SUBSPECIES OF BEGONIA (BEGONIACEAE) FROM ASIA
Authors: TEBBITT M. C.
Published: August 2005

Four new Asian taxa are described and illustrated as part of a forthcoming taxonomic revision of the cultivated species of Begonia (Begoniaceae). The new species B. argenteomarginata (sect. Symbegonia) is described from Papua New Guinea. Two new species from section Petermannia are described: B. polilloensis from the Philippines and B. rachmatii from Sulawesi, Indonesia, both of which are unusual in having palmately compound leaf blades. A key is provided for these and a previously described species, B. oligandra, also with palmately compound leaf blades and in section Petermannia. The new subspecies B. brevirimosa subsp. exotica (sect. Petermannia) is described from the Central Range of Papua New Guinea and a brief history of its cultivation is presented.
Modeling impacts of farming management alternatives on CO2, CH4, and N2O emissions: A case study for water management of rice agriculture of China
Authors: Li Changsheng , Frolking Steve , Xiao Xiangming , Moore Berrien , Boles Steve , Qiu Jianjun , Huang Yao , Salas William , Sass Ronald
Published: August 2005

Since the early 1980s, water management of rice paddies in China has changed substantially, with midseason drainage gradually replacing continuous flooding. This has provided an opportunity to estimate how a management alternative impacts greenhouse gas emissions at a large regional scale. We integrated a process‐based model, DNDC, with a GIS database of paddy area, soil properties, and management factors. We simulated soil carbon sequestration (or net CO2 emission) and CH4 and N2O emissions from China's rice paddies (30 million ha), based on 1990 climate and management conditions, with two water management scenarios: continuous flooding and midseason drainage. The results indicated that this change in water management has reduced aggregate CH4 emissions about 40%, or 5 Tg CH4 yr−1, roughly 5–10% of total global methane emissions from rice paddies. The mitigating effect of midseason drainage on CH4 flux was highly uneven across the country; the highest flux reductions (>200 kg CH4‐C ha−1 yr−1) were in Hainan, Sichuan, Hubei, and Guangdong provinces, with warmer weather and multiple‐cropping rice systems. The smallest flux reductions (<25 kg CH4‐C ha−1 yr−1) occurred in Tianjin, Hebei, Ningxia, Liaoning, and Gansu Provinces, with relatively cool weather and single cropping systems. Shifting water management from continuous flooding to midseason drainage increased N2O emissions from Chinese rice paddies by 0.15 Tg N yr−1 (∼50% increase). This offset a large fraction of the greenhouse gas radiative forcing benefit gained by the decrease in CH4 emissions. Midseason drainage‐induced N2O fluxes were high (>8.0 kg N/ha) in Jilin, Liaoning, Heilongjiang, and Xinjiang provinces, where the paddy soils contained relatively high organic matter. Shifting water management from continuous flooding to midseason drainage reduced total net CO2 emissions by 0.65 Tg CO2‐C yr−1, which made a relatively small contribution to the net climate impact due to the low radiative potential of CO2. The change in water management had very different effects on net greenhouse gas mitigation when implemented across climatic zones, soil types, or cropping systems. Maximum CH4 reductions and minimum N2O increases were obtained when the mid‐season draining was applied to rice paddies with warm weather, high soil clay content, and low soil organic matter content, for example, Sichuan, Hubei, Hunan, Guangdong, Guangxi, Anhui, and Jiangsu provinces, which have 60% of China's rice paddies and produce 65% of China's rice harvest.
Transtensional deformation in the central Himalaya and its role in accommodating growth of the Himalayan orogen
Authors: Murphy Michael A. , Copeland Peter
Published: August 2005

Field mapping, structural analysis, and geochronologic data from northwestern Nepal reveal major normal right‐slip motion along a previously unrecognized west‐northwest striking system of shear zones that we term the Gurla Mandhata–Humla fault system (GMH). The GMH obliquely cuts across the Greater Himalayan Crystalline sequence and into the Lesser Himalayan imbricate thrust belt via two right‐step‐over structures. The average slip direction on the GMH parallels the strike of the Himalayan orogen. Motion along this fault system has resulted in an apparent left separation of the South Tibet Detachment, Main Central thrust zone, and Lesser Himalayan imbricate thrust belt along a north striking segment of the fault system. We estimate a minimum of 21 km of net slip on the southern branch of the GMH by restoring the trace of the Main Central thrust zone parallel to the average slip direction on the fault. Taking into account slip estimates from the northern branch of the GMH yields a minimum net slip estimate of 24.4 to 32.4 km for the GMH. The 232Th/208Pb ion microprobe monazite ages from leucogranite bodies indicate that motion on the GMH occurred after 15 Ma. Its initiation immediately followed crustal thickening between the Main Central thrust zone and Indus‐Yalu suture zone. Motion on the GMH is contemporaneous with arc‐normal contraction in the southernmost Himalayan orogen. These observations can be explained by a model that involves foreland propagating structural systems facilitating arc‐normal contraction in the foreland and arc‐parallel extension in the hinterland that work together to maintain the arcuate shape of the Himalayan orogen.
Effective solute transport in temporally fluctuating flow through heterogeneous media
Authors: Dentz Marco , Carrera Jesus
Published: August 2005

We investigate the effective spreading of a passive solute evolving from a finite source in temporally fluctuating flow through a heterogeneous porous medium. To this end, we distinguish between two stochastic processes: one to represent the spatial variability of hydraulic conductivity (K) and one to model the temporal fluctuations of the hydraulic gradient (J). In a second‐order perturbation approach we systematically investigate the time evolution of “effective” dispersion coefficients, which quantify solute spreading in response to longitudinal and transverse fluctuations of the hydraulic gradient, spatial heterogeneity, and local dispersion. The effective dispersion coefficients consist of three contributions that reflect (1) local dispersion, (2) the interaction between local dispersion and spatial heterogeneity, and (3) the interaction of local dispersion, spatial heterogeneity, and temporal fluctuations (i.e., time fluctuations enhance spreading only as a consequence of the interplay with spatial heterogeneity). Furthermore, longitudinal and transverse temporal fluctuations of the hydraulic gradient induce macroscopic contributions to the longitudinal as well as the transverse effective dispersion coefficients, which can both be comparable to the contributions to longitudinal dispersion due to steady flow, i.e., large. An application to a field‐scale tracer experiment gives evidence that temporal fluctuations help in explaining observed macroscopic transverse solute spreading. Furthermore, aquifer remediation techniques that rely on the mixing of injected reactants with resident contaminants, or simply on dissolving these, can benefit from forcing velocity fluctuations. The presented results provide a quantitative basis for the design of such hydraulic manipulation techniques.
Electrical properties of partially saturated sandstones: Novel computational approach with hydrogeophysical applications
Authors: Brovelli A. , Cassiani G. , Dalla E. , Bergamini F. , Pitea D. , Binley A. M.
Published: August 2005

Electric and electromagnetic geophysical tools are suitable methods for investigating moisture content, transport, and storage properties of the subsoil with noninvasive surveys. Interpretation of field data is still based on empirical or semiempirical equations, which must be calibrated with complex, time‐consuming laboratory measurements. In this paper we develop pore‐scale models suitable for computing the effective electric conductivity and the effective permittivity of partially saturated porous media on the basis of simple structural parameters (grain size distribution and porosity). We compute the electrical conductivity with three approaches that model the conductivity of the shell of coating clay around solid grains of shaly sandstones using different assumptions. We compare the simulated results with experimental data from Sherwood Sandstone (UK) and discuss the effect of these assumptions on the effective conductivity. Simulations performed using a modeling approach that accounts for interaction between volume and surface conduction show an excellent agreement with experimental data. We also model the effective permittivity of the same porous medium at several saturation values and obtain a good match with laboratory measurements.
Identifying the regional thermal‐IR radiative signature of mineral dust with MODIS
Authors: Darmenov Anton , Sokolik Irina N.
Published: August 2005

We use MODIS Terra Level 1B data containing calibrated and geolocated radiances to investigate a regional signature of wind‐blown mineral dust in the thermal‐IR. MODIS data over oceans for the 2000–2004 time period were examined for the presence of dust plumes that originate from the main dust sources located in East and South Asia, Middle East, Northern Africa, and Australia. A number of representative cases for different source regions were selected and analyzed in terms of brightness temperatures at three IR channels centered at 8.55, 11.03, and 12.02 μm. The distinct differences in the thermal‐IR signature of atmospheric dust for the considered regions were found. Our analysis indicates that these differences are likely due to different mineralogical composition, although other factors (e.g., multilayered vertical distribution) may be also involved. Implications of our findings to the detection of dust based on the techniques using brightness temperature differences are discussed.
Seismic signature of intracrustal magmatic intrusions in the Eastern Betics (Internal Zone), SE Iberia
Authors: Julià J. , Mancilla F. , Morales J.
Published: August 2005

Receiver functions at three broad‐band stations located in the most easterly Inner Betics have been analyzed to investigate the structure of its underlying crust and uppermost mantle. These stations are located within a geologically distinctive block bounded by the Palomares/Alhama de Murcia faults, which is characterized by high heat‐flow values, widespread strike‐slip faulting and Neogene volcanism. Our analysis shows that a low velocity zone pervades the uppermost mantle beneath the stations, and that the overlying crust has a high Vp/Vs ratio and a prominent intracrustal low velocity zone (i) between the Palomares and Alhama de Murcia faults and (ii) east of Murcia, perhaps thermally perturbing the upper crust north and east of Cartagena. Independent studies show that the seismic velocities of the intervening mantle lid are normal beneath the stations, and we suggest that our observations result from rapidly ascending magma diapirs ponding at intracrustal levels within the distinctive block.
A modeling study of dynamic and thermodynamic mechanisms for summer drying in response to global warming
Authors: Findell Kirsten L. , Delworth Thomas L.
Published: August 2005

Past studies have suggested that increasing atmospheric CO2 will lead to a significant reduction of soil moisture during summer in the extratropics. These studies showed an increase in wintertime rainfall over most mid‐latitude continental regions when CO2 is doubled, an earlier snowmelt season and onset of springtime evaporation, and a higher ratio of evaporation to precipitation in summer. These factors led to large‐scale increases in soil moisture in winter and decreases in summer. We find that the above processes are important in simulated summer drying in a newly developed climate model. In addition to these thermodynamic processes, we find that changes in atmospheric circulation play an important role in regional hydroclimatic changes. Additional experiments show that the atmospheric circulation changes are forced by the CO2‐induced warming of the ocean, particularly the tropical ocean. These results highlight the importance of sea surface temperature changes for regional hydroclimatic changes.
Toward the development of new standard radiation belt and space plasma models for spacecraft engineering
Authors: Lauenstein Jean‐Marie , Barth Janet L. , Sibeck David G.
Published: August 2005

An international meeting on New Standard Radiation Belt and Space Plasma Models for Spacecraft Engineering, sponsored by NASA's Living With a Star Program, was held in 2004 to begin rebuilding the infrastructure required to develop new standard radiation belt and plasma environment models. The goal of one standard model will be accomplished in stages, including the formation of interim regional models, the calibration and incorporation of existing data sets, and the gathering of new data through future science missions. The Committee on Space Research/Panel for Radiation Belt Environment Modeling will play a central role in standardization and data archiving. Workshop attendees support the standardization of two interim models: a model of geostationary orbit electrons and a model of inner belt protons. Two future missions are planned or are being planned to provide missing measurements and to increase the scientific understanding of the particle dynamics. This information will lead to more robust modeling of the particle environment for the design and operation of spacecraft for space exploration as well as for industry and military applications.
Least cost design of groundwater quality monitoring networks
Authors: Zhang Yingqi , Pinder George F. , Herrera Graciela S.
Published: August 2005

A genetic algorithm combined with a static Kalman filter and a stochastic groundwater flow and contaminant transport model can be used to determine when and where to take samples to reduce the uncertainty associated with the statistical distribution describing a groundwater contamination concentration field at least cost. The use of a Kalman filter requires an initial estimate of the concentration field as well as its error covariance matrix, which are generated as the output of the simulation model. The random field input to the simulator, namely, realizations of the hydraulic conductivity field, can be generated using a Latin hypercube sampling technique. Employing the proposed optimal design strategy, a cost‐effective groundwater sampling network design is realized. The proposed methodology is applied to a field problem.
Molecular motions of different scales at thin polystyrene film surface by lateral force microscopy
Authors: Fu Jun , Li Binyao , Han Yanchun
Published: August 2005

Lateral force microscopy (LFM) was used to probe the molecular motions at thin polystyrene film surface. The effect of the applied load on the LFM measurements was investigated by presenting both the LFM results and the surface morphology after several scans over the same area. Depending on the loads, the scanning can be nonperturbative (without alternating the surface morphology) or perturbative (patterning the surface). Temperature-dependent LFM measurements were conducted in order to determine the apparent transitions at the surface. Perturbative scans under high loads (e.g., 150nN) witnessed that the apparent transitions shifted to low temperatures with an increasing scan rate, while the transitions behaved oppositely under lower loads (1, 10, and 20nN). The heating effect is suggested to account for the behavior under high loads. According to our results from nonperturbative LFM, the apparent glass transition temperature (Tgs) is more than 10K lower than the bulk value. Moreover, rate-dependent LFM measurements were performed under 1nN in order to detect the surface molecular motions. Time-temperature superposition yields a master curve exhibiting three apparent relaxation peaks. The molecular motions at the surface are discussed on the context of the coupling model.
Phase transition processes and magnetocaloric effects in the Heusler alloys NiMnGa with concurrence of magnetic and structural phase transition
Authors: Long Y. , Zhang Z. Y. , Wen D. , Wu G. H. , Ye R. C. , Chang Y. Q. , Wan F. R.
Published: August 2005

The Ni2MnGa-based Heusler alloys with high magnetocaloric effect have attracted considerable attention as a promising magnetic refrigerant. The phase-transition processes and magnetic entropy changes in the NiMnGa alloys with the concurrence of magnetic and structural phase transitions were studied. The ac magnetic susceptibility results showed the magnetic transition occurred during the reverse martensitic phase transition in the Ni55.5Mn20Ga24.5 alloy and the direct transition from the ferromagnetic matrensitic phase to the paramagnetic austenitic phase occurred in the Ni54.9Mn20.5Ga24.6 alloy. When the magnetic field had changed to 2 T, a comparable large magnetic entropy change was observed in both the Ni55.5Mn20Ga24.5 and Ni54.9Mn20.5Ga24.6 alloys, which is speculated as the result of the discontinuous change of magnetization near the phase transition.
Constant-atomic-final-state filtering of dissociative states in the O1s→σ* core excitation in O2
Authors: Hjelte I. , Björneholm O. , Carravetta V. , Angeli C. , Cimiraglia R. , Wiesner K. , Svensson S. , Piancastelli M. N.
Published: August 2005

The below-threshold region in core-excited O2 is very complex, consisting of a multitude of exchange-split states with mixed molecular orbital-Rydberg character. We have investigated the nature of these intermediate states by resonant Auger spectroscopy. In particular, we have obtained constant-atomic-final-state yield curves for several atomic peaks in the electron decay spectra which are stemming from ultrafast dissociation. The relative intensity of Auger decay leading to atomic final states is considered a signature of the relative weight of the σ* character. This method allows one to “filter out” intermediate states with dissociative character. Extensive calculations have been performed by multireference configuration interaction at different interatomic distances in order to evaluate the potential curves of the core-excited states and propose a qualitative description of the dissociative molecular dynamics. The calculations show that the core-excited states have a relevant admixture of excitations to orbitals with Rydberg character and excitations to the σ* orbital with different spin couplings. A diabatization of the adiabatic potential curves shows that the coupling between Rydberg and σ* diabatic states is very different at the different crossing points and ultrafast dissociation occurs more easily on the lowest σ* diabatic potential curve. As a consequence, the observation of atomic peaks only in the lower-energy region of the absorption curve is well justified.
Chemistry at corners and edges: Generation and adsorption of H atoms on the surface of MgO nanocubes
Authors: Sterrer Martin , Berger Thomas , Diwald Oliver , Knözinger Erich , Sushko Peter V. , Shluger Alexander L.
Published: August 2005

We used UV light to generate site-selective O− hole centers at three-coordinated corner oxygen sites on MgO nanocubes. These highly reactive O− radicals split H2 homolytically and, in the course of this reaction, become hydroxylated and produce hydrogen atoms. The hydrogen atoms adsorb predominantly at cube edges and dissociate into surface-trapped electrons and protons. We propose that the experimentally observed (H+)(e−) centers are formed adjacent to the hydroxyl groups generated in the homolytic splitting process and can be defined as (H+)3C⋯(e−)(H+)NC centers where 3C and NC refer to the coordination numbers of the corresponding hydroxylated oxygen sites. Our ab initio embedded cluster calculations reveal that the electronic properties of (H+)3C⋯(e−)(H+)4C centers situated along MgO nanocube edges are consistent with both the electron-paramagnetic-resonance signal parameters and the reported optical-absorption properties. The transformation of corner O− centers into the (H+)3C⋯(e−)(H+)NC-type centers prevents their recombination with electronic surface centers and, hence, significantly alters the electronic structure of MgO nanocubes by introducing shallow electron traps.
Nonlinear transport properties of III-nitrides in electric field
Authors: Rodrigues Clóves G. , Vasconcellos Áurea R. , Luzzi Roberto , Freire Valder N.
Published: August 2005

We consider the transport properties of polar direct-gap semiconductors in an electric field, specializing the numerical calculation of the general theory to the case of n-doped III-nitrides, in particular, GaN, AlN, and InN. The nonequilibrium thermodynamic state of these materials—characterized by the variables so-called quasitemperature, quasichemical potential, and drift velocity of the carriers, and the quasitemperatures of longitudinal optical and acoustical phonons—is studied. The evolution equations of these variables—which are highly nonlinear—are derived, and the transient regime and the ensuing steady state are analyzed. The nonlinear transport is characterized and its main properties are discussed. In one case comparison with a recent Monte Carlo calculation is made and good agreement is obtained. In this paper we mainly consider the ultrafast transient, and in the following paper the steady state.
Nonlinear transport properties of doped III-N and GaAs polar semiconductors: A comparison
Authors: Rodrigues Clóves G. , Vasconcellos Áurea R. , Luzzi Roberto , Freire Valder N.
Published: August 2005

In the previous article we have presented a study of the transport properties of doped direct-gap inverted-band polar semiconductors III-nitrides and GaAs in the steady state, calculated with a nonlinear quantum transport theory based on a nonequilibrium ensemble formalism. In the present one such results are compared with calculations using Monte Carlo-modeling simulations and with experimental measurements. Materials of the n-type and p-type dopings in the presence of intermediate to high electric fields, and for several temperatures of the external reservoir, are considered. The agreement between the results obtained using the nonlinear quantum kinetic theory, with those of Monte Carlo calculations and experimental data is remarkably good, thus satisfactorily validating this powerful, concise, and physically sound formalism.
Discrete deposition as a powerful tool to govern magnetoresistance of the doped manganite films
Authors: Tovstolytkin A. I. , Pogorily A. N. , Matviyenko A. I. , Vovk A. Ya. , Wang Zh.
Published: August 2005

A peculiar preparation routine, namely, a discrete deposition, is proposed for a goal-oriented change of electric and magnetotransport properties of the doped manganite films. The distinguishing feature of such procedure is a division of the whole deposition process into several cycles consisting of the deposition itself and subsequent annealing of the sample in the deposition chamber. The investigations were carried out on a series of (La,Sr)MnO3 films with different numbers of deposition cycle n (1⩽n⩽5), as well as on a single-layer reference film. All the films were deposited on single-crystalline SrTiO3 (001) substrates held at a temperature of 700°C in Ar–O2 mixture using reactive magnetron sputtering technique and subjected to a postdeposition annealing at 750°C. It has been shown that the discrete deposition procedure results in the increase of the magnetic transition temperature, substantial drop of the resistivity, and reduction of the extrinsic magnetoresistance. It is shown that the proposed procedure strongly affects the dynamics of the film growth, minimizes the effects caused by substrate-induced stress, and leads to the improvement of the structural and magnetic homogeneities of the film layers, which are not adjacent to the substrate. All these effects become especially efficient for n⩾2.