bluuebunny/crossref_metadata_2025_split huggingface dataset:
RHD*DOL1 and RHD*DOL2 encode a partial D antigen and are in cis with the rare RHCE*ceBI allele in people of African descent
Authors: Roussel Michèle , Poupel Sylvie , Nataf Joëlle , Juszczak Geneviève , Woimant Geneviève , Mailloux Agnès , Menanteau Cécile , Pham Bach‐Nga , Rouger Philippe , Le Pennec Pierre‐Yves , Peyrard Thierry 
Published: June 2012

BACKGROUND: Several studies showed in people of African descent the existence of a genetic linkage between RHD alleles encoding a variant D antigen and a given altered RHCE*ce allele. RHCE*ceBI is a rare allele encountered in people of African descent, that encodes a Hr– hrS– Rhce protein. Our study shows that RHCE*ceBI appears to be genetically linked to two very similar variant RHD alleles, RHD*DOL1 and RHD*DOL2, and demonstrates for the first time that DOL‐2 is a partial D antigen.STUDY DESIGN AND METHODS: After finding out an individual with both RHCE*ceBI and RHD*DOL presumed to be in cis, we hypothesized a genetic linkage between those two genes. All individuals (n = 7) known to carry RHCE*ceBI in our laboratory, including the index case, were fully investigated at the serologic and molecular level.RESULTS: One individual with alloanti‐D, being homozygous for RHCE*ceBI and RHD*DOL2, allowed us to confirm the genetic linkage between those two genes, as well as the partial D status of DOL‐2. In the six RHCE*ceBI remaining individuals, three were found with RHD*DOL2 and 3 with RHD*DOL1, likely in cis. Three of them made an alloanti‐D; one was DOL‐1 and two were DOL‐2.CONCLUSION: The rare RHCE*ceBI allele appears to be in cis either with RHD*DOL1 or with RHD*DOL2 in people of African descent. DOL‐1 and DOL‐2 must be considered as partial D antigens. We recommend a systematic search for RHD*DOL1 and RHD*DOL2 in people found to carry RHCE*ceBI and vice versa, especially in patients with sickle cell disease.
Pioneering Advantages and Entrepreneurs' First‐mover Decisions: An Empirical Investigation for the United States and China
Authors: Zhao Y. Lisa , Erekson O. Homer , Wang Tang , Song Michael 
Published: June 2012

New ventures are often launched for the purpose of pioneering an innovative new product or service in the marketplace. Entrepreneurs or founders of new ventures thus often have to make the decision whether to be the market pioneer or the first mover. While being a first mover potentially is advantageous, it also involves taking risks and facing uncertainties. Entrepreneurs must assess the benefits and risks of pioneering in the first‐mover decision‐making process to realize the potential competitive advantages associated with being a pioneer.Previous research has shown how entrepreneurs perceive potential gains and losses associated with exploring opportunities as the key defining element of entrepreneurial decision‐making. Past studies have also indicated that cultural and business environmental factors affect both perceptions and decision‐making. However, studies to date have insufficiently addressed the relationship between entrepreneurs' perceived pioneering advantages/disadvantages and their first‐mover decisions, with little attention to cross‐national differences.This study includes hypotheses postulating how entrepreneurs' perceived advantages and disadvantages of pioneering affect the number of first‐mover decisions made by entrepreneurs in two different cultural contexts, the United States and China. We collect data from 152 U.S. entrepreneurs and 140 Chinese entrepreneurs over a four‐year period and carry out empirical tests on the hypotheses using Poisson regression models. Our results provide insight on how culture affects perceptions of advantages and disadvantages of pioneering, and how these perceptions impact the likelihood of making a first‐mover decision. We find that a higher level of perceived advantages will drive first‐mover decisions, whereas perceived disadvantages will deter first‐mover decisions. The negative effect of perceived erosion disadvantages on the number of first‐mover decisions was higher for Chinese entrepreneurs, consistent with the high risk‐aversion culture in China. However, this effect was not found for perceived uncertainty disadvantages, suggesting that the risk‐averse characteristics of Chinese entrepreneurs is an oversimplification, and that the Chinese cultural, business, and legal environment helps offset uncertainty disadvantages. We also find an interesting positive moderating effect of perceived advantage on the relationship between perceived disadvantages and the number of first‐mover decisions in China only. That is, if perceived advantages are low, Chinese entrepreneurs are more risk averse than U.S. entrepreneurs; but if perceived advantages are high, Chinese entrepreneurs are more risk‐seeking than U.S. entrepreneurs. This finding again challenges the risk aversion conclusion found by previous studies of Chinese managers.
Externally Directed and Internally Directed Market Launch Management: The Role of Organizational Factors in Influencing New Product Success
Authors: Kuester Sabine , Homburg Christian , Hess Silke C. 
Published: June 2012

Introducing new products remains a critical challenge for managers. Consumer acceptance of new products is key to new product success and requires the effective implementation of market launch activities. The present study describes the relationship between different types of market launch activities and market‐related, time‐related, and financial market launch success. The study's framework extends previous work on launch management by complementing the view that launch activities are predominantly outwardly directed with the notion that launch management can also be inwardly directed. More specifically, launch activities can both target customers as the external audience, for example, via communication and pricing, and address an internal audience, such as management and sales personnel, for example, using departmental coordination or employee incentives. The study also sets out to investigate how situational factors impact the relative effectiveness of both externally directed and internally directed launch activities in engendering successful new product launches. In particular, product newness, technology drivers, and firm size are considered as relevant variables.Structural equation analysis of data on 178 new products across industries provide empirical evidence that market launch success depends on the intensity of both externally directed and internally directed market launch activities. With regard to the overall impact of internally directed activities, the findings confirm that organizational factors and antecedents indeed play a critical role in new product launch and its respective performance with internally directed activities having an even stronger impact on time‐related and financial success than outwardly directed instruments. Specifically, these internal activities are often viewed as idiosyncratic resources that are hard for competitors to observe and are therefore more difficult—if not impossible—to replicate compared to externally directed activities in market launch. The paper clearly pinpoints that the successful launch of new products is a complex task that also necessitates the implementation of internally directed launch activities. Fast market penetration requires coordination among the different internal players as well as support from top management. Furthermore, the financial objectives of the market launch can only be met if employees and executives both receive the necessary incentives and support to effectively execute the new product introduction. The study also demonstrates that moderators impact the strength of the effectiveness of these two different types of market launch activities. This research provides important implications for launch management by advocating that the two foci on external and internal constituencies should not be pursued in isolation but that instead, the opposite is true.
Pressureless Sintering of Zirconium Diboride Ceramics with Boron Additive
Authors: Guo Wei‐Ming , Zhang Guo‐Jun , Yang Zhen‐Guo 
Published: June 2012

Influence of boron on densification and microstructure of zirconium diboride (
ZrB

2) ceramics using pressureless sintering has been studied. The
ZrB

2 powders were synthesized by borothermal reduction of
ZrO

2 with three different
ZrO

2/
B
ratios to produce powders nominally phase pure or that contained excess boron. The as‐synthesized powders were then densified by heating to temperatures from 1800°C to 2200°C. The incorporation of 1.2 wt% excess boron increased relative density from ~54.3% to ~96.1% by reacting with and removing oxide impurities (
ZrO

2 and
B

2

O

3) after sintering at 2000°C, whereas it also led to an exaggerated grain growth from 1–3 to 20–80 μm presumably due to high grain‐boundary mobility. The faster grain growth resulted in the formation of intragranular pores and prevented the
ZrB

2 ceramics from reaching full density. By the incorporation of 3 wt% excess boron, a fully dense
ZrB

2 ceramics with relative density of ~99.7% and grain size of 5–10 μm was obtained at 2000°C. The full densification was attributed to the synergistic effects of boron through oxide impurities removal and grain‐ growth inhibition.
Mating failure of female Parnassius smintheus butterflies: a component but not a demographic Allee effect
Authors: Matter Stephen F. , Roland Jens 
Published: June 2012

AbstractFemale mating success affects the ecology, evolution, and conservation of species. From a population dynamic perspective, female mating failure occurring due to low population density potentially translates into negative population growth, resulting in population extinction. Despite the implications, there have been surprisingly few comprehensive studies of both the causes and the population level effects of female mating failure for insects. Herein, we examined the mating success of female Parnassius smintheus Doubleday (Lepidoptera: Papilionidae) butterflies and its effects on population growth. Using mark‐recapture data amassed from 17 interconnected populations over 12 years, we assessed whether yearly female mating success varied with local population density, and whether population growth varied with mating success. We found that there was increased female mating failure at low population density – a component Allee effect. However, this effect did not result in a demographic Allee effect. We found that population growth was greatest at lowest densities and that there was no relationship between female mating success and population growth. These results along with a growing number of studies indicate that demographic Allee effects are much less common than component effects, and they may be relatively uncommon for insects in nature.
An evaluation of different saliva collection methods for detection of antibodies against hepatitis C virus (anti‐HCV)
Authors: Cruz H. M. , Marques V. A. , Villela‐Nogueira C. A. , do Ó K. M. R. , Lewis‐Ximenez L. L. , Lampe E. , Villar L. M. 
Published: June 2012

J Oral Pathol Med (2012) 41: 793–800Background:  Saliva samples can be used as an alternative fluid for against hepatitis C virus (anti‐HCV) detection owing to the ease of collection and excellent acceptability. This study was conducted to optimize a commercial enzyme immunoassay (EIA) to detect anti‐HCV in saliva samples.Methods:  Ninety‐six individuals donated paired serum and saliva samples that were obtained, using a commercial device (Salivette) and spitting into a sterile container. Initially, elution buffer for the Salivette samples, sample volume, incubation time and temperature, and two different anti‐HCV EIAs were evaluated. Using the optimized assay, three methods for cut‐off calculation were also evaluated.Results:  A 20‐fold increase in the sample volume for both collection methods was needed. Moreover, the Radim assay was the most appropriate assay for anti‐HCV detection in saliva samples, and the quality parameters were increased when a ROC curve was used to determine the cut‐off value. Using this optimized assay, the sensitivities, specificities, accuracies, positive and negative predictive values were above 90% for saliva obtained using both the Salivette and spitting methods. Using this assay, discordant false‐negative results were obtained for only two Salivette samples and five spitting samples. The concordance kappa was 93% for the Salivette method and 86.1% for the spitting method, demonstrating excellent performance.Conclusions:  Saliva samples obtained for both methods can be employed for anti‐HCV detection among HCV‐infected or HCV‐suspected cases, but several modifications must be performed on commercial EIAs to obtain good results. Moreover, samples obtained with commercial devices are more appropriate for anti‐HCV detection in saliva samples.
Quantifying landscape linkages among giant panda subpopulations in regional scale conservation
Authors: QI Dunwu , HU Yibo , GU Xiaodong , YANG Xuyi , YANG Guang , WEI Fuwen 
Published: June 2012

AbstractUnderstanding habitat requirements and identifying landscape linkages are essential for the survival of isolated populations of endangered species. Currently, some of the giant panda populations are isolated, which threatens their long‐term survival, particularly in the Xiaoxiangling mountains. In the present study, we quantified niche requirements and then identified potential linkages of giant panda subpopulations in the most isolated region, using ecological niche factor analysis and a least‐cost path model. Giant pandas preferred habitat with conifer forest and gentle slopes (>20 to ≤30°). Based on spatial distribution of suitable habitat, linkages were identified for the Yele subpopulation to 4 other subpopulations (Liziping, Matou, Xinmin and Wanba). Their lengths ranged from 15 to 54 km. The accumulated cost ranged from 693 to 3166 and conifer forest covered over 31%. However, a variety of features (e.g. major roads, human settlements and large unforested areas) might act as barriers along the linkages for giant panda dispersal. Our analysis quantified giant panda subpopulation connectivity to ensure long‐term survival.
Current hypotheses for the evolution of sex and recombination
Authors: HARTFIELD Matthew , KEIGHTLEY Peter D. 
Published: June 2012

AbstractThe evolution of sex is one of the most important and controversial problems in evolutionary biology. Although sex is almost universal in higher animals and plants, its inherent costs have made its maintenance difficult to explain. The most famous of these is the twofold cost of males, which can greatly reduce the fecundity of a sexual population, compared to a population of asexual females. Over the past century, multiple hypotheses, along with experimental evidence to support these, have been put forward to explain widespread costly sex. In this review, we outline some of the most prominent theories, along with the experimental and observational evidence supporting these. Historically, there have been 4 classes of theories: the ability of sex to fix multiple novel advantageous mutants (Fisher–Muller hypothesis); sex as a mechanism to stop the build‐up of deleterious mutations in finite populations (Muller's ratchet); recombination creating novel genotypes that can resist infection by parasites (Red Queen hypothesis); and the ability of sex to purge bad genomes if deleterious mutations act synergistically (mutational deterministic hypothesis). Current theoretical and experimental evidence seems to favor the hypothesis that sex breaks down selection interference between new mutants, or it acts as a mechanism to shuffle genotypes in order to repel parasitic invasion. However, there is still a need to collect more data from natural populations and experimental studies, which can be used to test different hypotheses.
Opportunism and the resilience of barnacles (Cirripedia: Thoracica) to environmental change
Authors: BUCKERIDGE John S. 
Published: June 2012

AbstractCirripede‐like organisms have their origins in the Palaeozoic, but until the Cainozoic, were represented primarily by pedunculated forms, such as the Scalpelliformes. Acorn barnacles (Balanomorpha) are first recorded after the Cretaceous–Tertiary extinction event. During the late Palaeogene, rapid radiation of cirripedes resulted in sufficient diversification for them to occupy most marine environments. That they survived both the Palaeocene–Eocene Thermal Maximum and the Pleistocene glaciation is testament to their ability to rapidly adapt to opportunities. The wide habitat distribution of balanomorphs in particular is unparalleled; they are known from the upper littoral (Chthamalus) to depths of 3600 m (Tetrachaelasma) and within this attached to rock, wood and miscellaneous flotsam, plus in symbiosis or commensalism with larger marine organisms. Darwin's (1854) view of the Tertiary as the age of barnacles is reflected in this diversity, distribution and biomass. All cirripedes are, nonetheless, at risk, from rapid habitat change, competition, pollution and, especially in light of their sessile habit, from predation. This paper assesses the viability of a number of cirripedes and concludes that the Lepadiformes, Scalpelliformes and Balanomorpha are the most resilient, and will most quickly adapt to occupy new niches when opportunities arise.
Direct impacts of climatic warming on heat stress in endothermic species: seabirds as bioindicators of changing thermoregulatory constraints
Authors: OSWALD Stephen A. , ARNOLD Jennifer M. 
Published: June 2012

AbstractThere is now abundant evidence that contemporary climatic change has indirectly affected a wide‐range of species by changing trophic interactions, competition, epidemiology and habitat. However, direct physiological impacts of changing climates are rarely reported for endothermic species, despite being commonly reported for ectotherms. We review the evidence for changing physiological constraints on endothermic vertebrates at high temperatures, integrating theoretical and empirical perspectives on the morphology, physiology and behavior of marine birds. Potential for increasing heat stress exposure depends on changes in multiple environmental variables, not just air temperature, as well as organism‐specific morphology, physiology and behavior. Endotherms breeding at high latitudes are vulnerable to the forecast, extensive temperature changes because of the adaptations they possess to minimize heat loss. Low‐latitude species will also be challenged as they currently live close to their thermal limits and will likely suffer future water shortages. Small, highly‐active species, particularly aerial foragers, are acutely vulnerable as they are least able to dissipate heat at high temperatures. Overall, direct physiological impacts of climatic change appear underrepresented in the published literature, but available data suggest they have much potential to shape behavior, morphology and distribution of endothermic species. Coincidence between future heat stress events and other energetic constraints on endotherms remains largely unexplored but will be key in determining the physiological impacts of climatic change. Multi‐scale, biophysical modeling, informed by experiments that quantify thermoregulatory responses of endotherms to heat stress, is an essential precursor to urgently‐needed analyses at the population or species level.
Is the expansion of the pine processionary moth, due to global warming, impacting the endangered Spanish moon moth through an induced change in food quality?
Authors: IMBERT Charles‐Edouard , GOUSSARD Francis , ROQUES Alain 
Published: June 2012

AbstractRecent climate change is known to affect the distribution of a number of insect species, resulting in a modification of their range boundaries. In newly colonized areas, novel interactions become apparent between expanding and endemic species sharing the same host. The pine processionary moth is a highly damaging pine defoliator, extending its range northwards and upwards in response to winter warming. Its expansion in the Alps has resulted in an invasion into the range of the Spanish moon moth, a red listed species developing on Scots pine. Pine processionary moth larvae develop during winter, preceding those of the moon moth, which hatch in late spring. Using pine trees planted in a clonal design, we experimentally tested the effect of previous winter defoliation by pine processionary moth larvae upon the survival and development of moon moth larvae. Feeding on foliage of heavily defoliated trees (>50%) resulted in a significant increase in the development time of moon moth larvae and a decrease in relative growth rate compared to feeding on foliage of undefoliated trees. Dry weight of pupae also decreased when larvae were fed with foliage of defoliated trees, and might, therefore, affect imago performances. However, lower defoliation degrees did not result in significant differences in larval performances compared to the control. Because a high degree of defoliation by pine processionary moth is to be expected during the colonization phase, its arrival in subalpine pine stands might affect the populations of the endangered moon moth
Self‐reported quantity of daily water intake and urine output in healthy young
Authors: Altun İnsaf , Çınar Nursan Dede , Kaşıkçı Mağfiret Kara 
Published: June 2012

Water is an essential nutrient and adequate intake and output of water is required for health maintenance. Water homeostasis is vital for life and optimal function and considerable interest surrounds the issue of recommendations for water consumption in healthy individuals. Few studies are available about self‐reported water intake and urine output.The aim of this study was to assess the quantity of water intake and urine output in 24‐h period in healthy young individuals. This prospective study was carried out on 31 students aged 18–24 years undergoing nursing education in a University during January 2011 in Sakarya, Turkey. Healthy young individuals were recruited for determination of the quantity of water taken in and urine excretion along 24 h; they recorded fluid input and urine output.The students collected the data during weekend break. In our study, the total daily fluid intake (mL) for females was 2082·6 ± 687·1 and the total daily fluid intake (mL) for males was 2720·8 ± 717·4. The total daily quantity of urine (mL) for females was 1623·4 ± 602·4 and the total daily quantity of urine (mL) for males was 1818·3 ± 420·6.This research may be the source for similar studies that could include seasonal changes, climates, cultures and different age groups.