The costal skeleton of the Regourdou 1 Neandertal.
Gómez-Olivencia, Asier; Holliday, Trenton; Madelaine, Stéphane; Couture-Veschambre, Christine; Maureille, Bruno
2018-02-26
The morphology and size of the Neandertal thorax is a subject of growing interest due to its link to general aspects of body size and shape, including physiological aspects related to bioenergetics and activity budgets. However, the number of well-preserved adult Neandertal costal remains is still low. The recent finding of new additional costal remains from the Regourdou 1 (R1) skeleton has rendered this skeleton as one of the most complete Neandertal costal skeletons with a minimum of 18 ribs represented, five of which are complete or virtually complete. Here we describe for the first time all the rib remains from R1 and compare them to a large modern Euroamerican male sample as well as to other published Neandertal individuals. The costal skeleton of this individual shows significant metric and morphological differences from our modern human male comparative sample. The perceived differences include: dorsoventrally large 1st and 2nd ribs, 3rd ribs with a very closed dorsal curvature and large maximum diameters at the posterior angle, a large tubercle-iliocostal line distance in the 4th rib, thick shafts at the dorsal end of its 6th ribs, thick mid-shafts of the 8th ribs, large articular tubercles at the 9th ribs, and thick shafts of the 11th and 12th ribs. Here we also describe a new mesosternal fragment: the left lateral half of sternebral segments 4 and 5. This portion reveals that the mesosternum of R1 had a sternal foramen in its inferiormost preserved sternal segment and supports previous estimation of the total length of this mesosternum. The new costal remains from R1 support the view that Neandertals, when compared with modern humans, show a significantly different thorax, consistent with differences found in other anatomical regions such as the vertebral column and pelvis. Copyright © 2018 Elsevier Ltd. All rights reserved.
Trends in the earnings gender gap among dentists, physicians, and lawyers.
Nguyen Le, Thanh An; Lo Sasso, Anthony T; Vujicic, Marko
2017-04-01
The authors examined the factors associated with sex differences in earnings for 3 professional occupations. The authors used a multivariate Blinder-Oaxaca method to decompose the differences in mean earnings across sex. Although mean differences in earnings between men and women narrowed over time, there remained large, unaccountable earnings differences between men and women among all professions after multivariate adjustments. For dentists, the unexplained difference in earnings for women was approximately constant at 62% to 66%. For physicians, the unexplained difference in earnings for women ranged from 52% to 57%. For lawyers, the unexplained difference in earnings for women was the smallest of the 3 professions but also exhibited the most growth, increasing from 34% in 1990 to 45% in 2010. The reduction in the earnings gap is driven largely by a general convergence between men and women in some, but not all, observable characteristics over time. Nevertheless, large unexplained gender gaps in earnings remain for all 3 professions. Policy makers must use care in efforts to alleviate earnings differences for men and women because measures could make matters worse without a clear understanding of the nature of the factors driving the differences. Copyright © 2017 American Dental Association. Published by Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Kulkarni, Devdatta; Chen, Edward; Ho, Mantak; Karmaker, Haran
For offshore large multi-megawatt direct drive wind generators, because of its ability to generate high flux fields, superconducting (SC) technology can offer significant size and mass reduction over traditional technologies. However, cryogenic cooling design remains as one of the major obstacles to overcome. Different cryogenic cooling designs, such as warm shaft and cold shaft rotor design, present different advantages and challenges technically and commercially. This paper presents the investigations on both designs for large SC generators from manufacturability and service perspectives.
Large Polyglutamine Repeats Cause Muscle Degeneration in SCA17 Mice
Huang, Shanshan; Yang, Su; Guo, Jifeng; Yan, Sen; Gaertig, Marta A.; Li, Shihua; Li, Xiao-Jiang
2015-01-01
SUMMARY In polyglutamine (polyQ) diseases, large polyQ repeats cause juvenile cases with different symptoms than adult-onset patients, who carry smaller expanded polyQ repeats. The mechanisms behind the differential pathology mediated by different polyQ repeat lengths remain unknown. By studying knock-in mouse models of spinal cerebellar ataxia-17 (SCA17), we found that a large polyQ (105 glutamines) in the TATA box-binding protein (TBP) preferentially causes muscle degeneration and reduces the expression of muscle-specific genes. Direct expression of TBP with different polyQ repeats in mouse muscle revealed that muscle degeneration is mediated only by the large polyQ repeats. Different polyQ repeats differentially alter TBP’s interaction with neuronal and muscle-specific transcription factors. As a result, the large polyQ repeat decreases the association of MyoD with TBP and DNA promoters. Our findings suggest that specific alterations in protein interactions by large polyQ repeats may account for the unique pathology in juvenile polyQ diseases. PMID:26387956
DETAIL VIEW OF LOWER CYANIDE PROCESSING WORKS, LOOKING SOUTHWEST FROM ...
DETAIL VIEW OF LOWER CYANIDE PROCESSING WORKS, LOOKING SOUTHWEST FROM LARGE TAILINGS PILE. THE REMAINS OF THREE TEN FOOT DIAMETER SETTLING TANKS ARE AT CENTER. THE SCATTER IN THE CENTER FOREGROUND IS THE REMAINS OF A LARGE RECTANGULAR HOLDING TANK POSSIBLY A SETTLING TANK. THIS AREA WAS MOST LIKELY CONSTRUCTED LATER IN THE TWENTIETH CENTURY AFTER MINING HAD CEASED AND ONLY TAILINGS WERE BEING RECLAIMED. AN EXACT DATE CANNOT BE DETERMINED HOWEVER THESE WORKS ARE DISTINCTLY DIFFERENT THAN THE ORIGINAL LAYOUT. THE SANDY AREA THAT OCCUPIES THE FOREGROUND AND THE CENTER ARE TAILINGS. - Keane Wonder Mine, Park Route 4 (Daylight Pass Cutoff), Death Valley Junction, Inyo County, CA
Treatment of anemia in chronic kidney disease: known, unknown, and both.
Foley, Robert N
2011-01-01
Erythropoiesis is a rapidly evolving research arena and several mechanistic insights show therapeutic promise. In contrast with the rapid advance of mechanistic science, optimal management of anemia in patients with chronic kidney disease remains a difficult and polarizing issue. Although several large hemoglobin target trials have been performed, optimal treatment targets remain elusive, because none of the large trials to date have unequivocally identified differences in primary outcome rates or death rates, and because other reported outcomes indicate the potential for harm (rates of stroke, early requirement for dialysis, and vascular access thrombosis) and benefit (reductions in transfusion requirements and fatigue).
A fast time-difference inverse solver for 3D EIT with application to lung imaging.
Javaherian, Ashkan; Soleimani, Manuchehr; Moeller, Knut
2016-08-01
A class of sparse optimization techniques that require solely matrix-vector products, rather than an explicit access to the forward matrix and its transpose, has been paid much attention in the recent decade for dealing with large-scale inverse problems. This study tailors application of the so-called Gradient Projection for Sparse Reconstruction (GPSR) to large-scale time-difference three-dimensional electrical impedance tomography (3D EIT). 3D EIT typically suffers from the need for a large number of voxels to cover the whole domain, so its application to real-time imaging, for example monitoring of lung function, remains scarce since the large number of degrees of freedom of the problem extremely increases storage space and reconstruction time. This study shows the great potential of the GPSR for large-size time-difference 3D EIT. Further studies are needed to improve its accuracy for imaging small-size anomalies.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gao, Zhongming; Liu, Heping; Katul, Gabriel G.
It is now accepted that large-scale turbulent eddies impact the widely reported non-closure of the surface energy balance when latent and sensible heat fluxes are measured using the eddy covariance method in the atmospheric surface layer (ASL). However, a mechanistic link between large eddies and non-closure of the surface energy balance remains a subject of inquiry. Here, measured 10 Hz time series of vertical velocity, air temperature, and water vapor density collected in the ASL are analyzed for conditions where entrainment and/or horizontal advection separately predominate. The series are decomposed into small- and large- eddies based on a frequency cutoffmore » and their contributions to turbulent fluxes are analyzed. Phase difference between vertical velocity and water vapor density associated with large eddies reduces latent heat fluxes, especially in conditions where advection prevails. Furthermore, enlarged phase difference of large eddies linked to entrainment or advection occurrence leads to increased residuals of the surface energy balance.« less
Gao, Zhongming; Liu, Heping; Katul, Gabriel G.; ...
2017-03-16
It is now accepted that large-scale turbulent eddies impact the widely reported non-closure of the surface energy balance when latent and sensible heat fluxes are measured using the eddy covariance method in the atmospheric surface layer (ASL). However, a mechanistic link between large eddies and non-closure of the surface energy balance remains a subject of inquiry. Here, measured 10 Hz time series of vertical velocity, air temperature, and water vapor density collected in the ASL are analyzed for conditions where entrainment and/or horizontal advection separately predominate. The series are decomposed into small- and large- eddies based on a frequency cutoffmore » and their contributions to turbulent fluxes are analyzed. Phase difference between vertical velocity and water vapor density associated with large eddies reduces latent heat fluxes, especially in conditions where advection prevails. Furthermore, enlarged phase difference of large eddies linked to entrainment or advection occurrence leads to increased residuals of the surface energy balance.« less
The Relationship between Workplace Climate, Motivation and Learning Approaches for Knowledge Workers
ERIC Educational Resources Information Center
Vanthournout, Gert; Noyens, Dorien; Gijbels, David; Van den Bossche, Piet
2014-01-01
Workplace learning is becoming a central tenet for a large proportion of today's employees. This seems especially true for so-called knowledge workers. Today, it remains unclear how differences in the quality of workplace learning are affected by differences in perception of the workplace environment and the motivation of knowledge workers to…
Differences in Access to Care among Students Using School-Based Health Centers
ERIC Educational Resources Information Center
Parasuraman, Sarika Rane; Shi, Leiyu
2015-01-01
Health care reform has changed the landscape for the nation's health safety net, and school-based health centers (SBHCs) remain an important part of this system. However, few large-scale studies have been conducted to assess their impact on access to care. This study investigated differences in access among a nationally representative sample of…
Judgment of Daytime Sleepiness in Self-Reported Short, Long and Midrange Sleepers
ERIC Educational Resources Information Center
Mairesse, Olivier; Neu, Daniel; Migeotte, Pierre-Francois; Pattyn, Nathalie; Hofmans, Joeri; Theuns, Peter; Cluydts, Raymond; De Valck, Elke
2012-01-01
Sleep-wake behavior, as well as sleepiness, is regulated by the joint action of an exponentially increasing drive for sleep--sleep homeostasis--and by variations in sleep propensity due to a biological circadian oscillator. However, large inter-individual differences remain. Short and long sleepers have been known to differ in the amount of…
Professional Development: Then and Now
ERIC Educational Resources Information Center
Bolt, Susan
2012-01-01
Technological developments have altered pedagogies in classroom teaching but approaches to teacher professional development have remained largely unchanged. The purpose of this paper is to describe an evolving learning process that spans the last decade and draws from three different investigations into professional development. The author…
Lopez, David Fernandez; Faustino, Joel; Daneman, Richard; Zhou, Lu; Lee, Sarah; Derugin, Nikita; Wendland, Michael F.; Vexler, Zinaida S
2012-01-01
The immaturity of the CNS at birth greatly affects injury after stroke but the contribution of the blood-brain barrier (BBB) to the differential response to stroke in adults and neonates is poorly understood. We asked if the structure and function of the BBB is disrupted differently in neonatal and adult rats by transient middle cerebral artery occlusion. In adult rats, albumin leakage into injured regions was markedly increased during 2–24 h reperfusion but leakage remained low in the neonates. Functional assays employing intravascular tracers in the neonates showed that BBB permeability to both large (70-kDa dextran) and small (3-kDa dextran, Gd-DTPA) tracers remained largely undisturbed 24h after reperfusion. The profoundly different functional integrity of the BBB was associated with the largely nonoverlapping patterns of regulated genes in endothelial cells purified from injured and uninjured adult and neonatal brain at 24h (endothelial transcriptome, 31,042 total probe sets). Within significantly regulated 1,266 probe sets in injured adults and 361 probe sets in neonates, changes in the gene expression of the basal lamina components, adhesion molecules, the tight junction protein occludin, and MMP-9 were among the key differences. The protein expression of collagen-IV, laminin, claudin-5, occludin and ZO-1 was also better preserved in neonatal rats. Neutrophil infiltration remained low in acutely injured neonates but neutralization of CINC-1 in the systemic circulation enhanced neutrophil infiltration, BBB permeability and injury. The markedly more integrant BBB in neonatal brain than in adult brain after acute stroke may have major implications for the treatment of neonatal stroke. PMID:22787045
USDA-ARS?s Scientific Manuscript database
Plant polyploidy potentially affects plant-insect interactions; however, its effect on insect fitness remains largely unexplored. Alternanthera philoxeroides is a South American amphibious Amaranthaceae, which invades aquatic and terrestrial habitats. Different morphotypes and cytotypes were identif...
Internal structure of normal maize starch granules revealed by chemical surface gelatinization.
Pan, D D; Jane, J I
2000-01-01
Normal maize starch was fractionated into two sizes: large granules with diameters more than 5 microns and small granules with diameters less than 5 microns. The large granules were surface gelatinized by treating them with an aqueous LiCl solution (13 M) at 22-23 degrees C. Surface-gelatinized remaining granules were obtained by mechanical blending, and gelatinized surface starch was obtained by grinding with a mortar and a pestle. Starches of different granular sizes and radial locations, obtained after different degrees of surface gelatinization, were subjected to scanning electron microscopy, iodine potentiometric titration, gel-permeation chromatography, and amylopectin branch chain length analysis. Results showed that the remaining granules had a rough surface with a lamella structure. Amylose was more concentrated at the periphery than at the core of the granule. Amylopectin had longer long B-chains at the core than at the periphery of the granule. Greater proportions of the long B-chains were present at the core than at the periphery of the granule.
Method for revealing biases in precision mass measurements
NASA Astrophysics Data System (ADS)
Vabson, V.; Vendt, R.; Kübarsepp, T.; Noorma, M.
2013-02-01
A practical method for the quantification of systematic errors of large-scale automatic comparators is presented. This method is based on a comparison of the performance of two different comparators. First, the differences of 16 equal partial loads of 1 kg are measured with a high-resolution mass comparator featuring insignificant bias and 1 kg maximum load. At the second stage, a large-scale comparator is tested by using combined loads with known mass differences. Comparing the different results, the biases of any comparator can be easily revealed. These large-scale comparator biases are determined over a 16-month period, and for the 1 kg loads, a typical pattern of biases in the range of ±0.4 mg is observed. The temperature differences recorded inside the comparator concurrently with mass measurements are found to remain within a range of ±30 mK, which obviously has a minor effect on the detected biases. Seasonal variations imply that the biases likely arise mainly due to the functioning of the environmental control at the measurement location.
Starkovich, Britt M; Conard, Nicholas J
2015-12-01
This paper presents the faunal remains from the new excavation area at the Lower Paleolithic site of Schöningen. The focus of the study is on the southern extension of the main find horizon (Spear Horizon South), which includes the layer that yielded the famous Schöningen spears (13 II-4). Taxonomic data corroborate previous studies, that hominins primarily hunted Equus mosbachensis, a large Pleistocene horse. Equid body part representation at the site suggests that the animals were hunted and butchered locally. There is no evidence for density-mediated attrition in the assemblage. Weathering damage is uncommon, though there is ample evidence that carnivores had access to the bone. Carnivore bite sizes were measured and compared to experimental data provided by previous authors. Based on relationships between bite size and carnivore behavior and body size, we conclude that the primary modifying agents were large carnivores (i.e., wolves or saber-toothed cats). Previous studies show that carnivores often had secondary access to the remains, after hominins. Cut marks are commonly arranged haphazardly on the bones. This may indicate that multiple hominins participated in the butchery of horse skeletons, or that they were butchered over the course of hours or days. Cut marks on axial elements are more "orderly," which probably reflects the physical logistics of orienting one's body in relation to a large carcass. These data differ from sites formed by Middle and Upper Paleolithic hominins, which might suggest that in later times, a system of organized meat provisioning was already in place. Taken together, the faunal evidence from the Spear Horizon South indicates that late Lower Paleolithic hominins using the site understood the behaviors of different prey species, hunted socially to take down large game, and successfully competed with large carnivores on the landscape for primary access to ungulate remains. Copyright © 2015 Elsevier Ltd. All rights reserved.
Anxiety, Depression, Hostility and General Psychopathology: An Arabian Study.
ERIC Educational Resources Information Center
Ibrahim, Abdel-Sattar; Ibrahim, Radwa M.
In Arabian cultures, the psychosocial characteristics of psychopathological trends, including depression, anxiety, and hostility remain largely unknown. Scales measuring depression, anxiety, and hostility were administered to a voluntary sample of 989 Saudi Arabian men and 1,024 Saudi women coming from different social, economical, and educational…
Nonlinear Geometric Effects in Mechanical Bistable Morphing Structures
NASA Astrophysics Data System (ADS)
Chen, Zi; Guo, Qiaohang; Majidi, Carmel; Chen, Wenzhe; Srolovitz, David J.; Haataja, Mikko P.
2012-09-01
Bistable structures associated with nonlinear deformation behavior, exemplified by the Venus flytrap and slap bracelet, can switch between different functional shapes upon actuation. Despite numerous efforts in modeling such large deformation behavior of shells, the roles of mechanical and nonlinear geometric effects on bistability remain elusive. We demonstrate, through both theoretical analysis and tabletop experiments, that two dimensionless parameters control bistability. Our work classifies the conditions for bistability, and extends the large deformation theory of plates and shells.
Coexistence of several currencies in presence of increasing returns to adoption
NASA Astrophysics Data System (ADS)
Lamarche-Perrin, Alex; Orléan, André; Jensen, Pablo
2018-04-01
We present a simplistic model of the competition between different currencies. Each individual is free to choose the currency that minimizes his transaction costs, which arise whenever his exchanging relations have chosen a different currency. We show that competition between currencies does not necessarily converge to the emergence of a single currency. For large systems, we prove that two distinct communities using different currencies in the initial state will remain forever in this fractionalized state.
Differences in delay discounting between smokers and nonsmokers remain when both rewards are delayed
Mitchell, Suzanne H.; Wilson, Vanessa B.
2013-01-01
Rationale When offered a choice between a small monetary reward available immediately (SmallNow) versus a larger reward available after a delay (LargeLater), smokers select the SmallNow alternative more than nonsmokers. That is, smokers discount the value of the LargeLater reward more than nonsmokers. Objectives To investigate whether this group difference was due to smokers overweighing the value of rewards available immediately compared with nonsmokers, we examined whether the group difference was also seen when both alternatives were delayed, i.e., when choosing between a SmallSoon reward and a LargeLater reward. Methods In Experiment 1, smokers and nonsmokers completed a task including SmallNow versus LargeLater choices and SmallSoon versus LargeLater choices. In Experiment 2, smokers and nonsmokers completed the same task but with hypothetical choices. Results Analyses using hyperbolic and double exponential (β-δ) models replicate prior findings that smokers discount the LargeLater reward more than nonsmokers when the smaller reward is available immediately. The smoker-nonsmoker difference was also seen when the smaller reward was slightly delayed, though this effect was primarily driven by heightened discounting in male smokers. However, for potentially real rewards only, this smoker-nonsmoker difference was significantly reduced when the smaller reward was delayed. Conclusions The smoker-nonsmoker difference in discounting is not confined to situations involving immediate rewards. Differences associated with potentially real vs. hypothetical rewards and gender underscore the complexity of the smoking-delay discounting relationship. PMID:21983917
Sex-related differences in murine hepatic transcriptional and proteomic responses to TCDD
DOE Office of Scientific and Technical Information (OSTI.GOV)
Prokopec, Stephenie D.; Watson, John D.; Lee, Jamie
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is an environmental contaminant that produces myriad toxicities in most mammals. In rodents alone, there is a huge divergence in the toxicological response across species, as well as among different strains within a species. But there are also significant differences between males and females animals of a single strain. These differences are inconsistent across model systems: the severity of toxicity is greater in female rats than males, while male mice and guinea pigs are more sensitive than females. Because the specific events that underlie this difference remain unclear, we characterized the hepatic transcriptional response of adult male andmore » female C57BL/6 mice to 500 μg/kg TCDD at multiple time-points. The transcriptional profile diverged significantly between the sexes. Female mice demonstrated a large number of altered transcripts as early as 6 h following treatment, suggesting a large primary response. Conversely, male animals showed the greatest TCDD-mediated response 144 h following exposure, potentially implicating significant secondary responses. Nr1i3 was statistically significantly induced at all time-points in the sensitive male animals. This mRNA encodes the constitutive androstane receptor (CAR), a transcription factor involved in the regulation of xenobiotic metabolism, lipid metabolism, cell cycle and apoptosis. Surprisingly though, changes at the protein level (aside from the positive control, CYP1A1) were modest, with only FMO3 showing clear induction, and no genes with sex-differences. Thus, while male and female mice show transcriptional differences in their response to TCDD, their association with TCDD-induced toxicities remains unclear. - Highlights: • Differences exist between the toxicity phenotypes to TCDD in male and female mice. • TCDD-mediated transcriptomic differences were identified between the sexes. • Resistant female mice displayed a large, early-onset, transcriptomic response. • Sensitive male mice displayed a large, late-onset, transcriptomic response. • Fmo2, Fmo3 and Nr1i3 were induced across the time-course in only male mice.« less
ERIC Educational Resources Information Center
Pollack, Terry M.
2013-01-01
Informal "teacher talk" about students is ubiquitous, but it remains largely unexamined. This study critically examines casual, everyday teacher discourse about students perceived to be racially or culturally "different." Data were collected through participants' journal entries, group discussion, and interviews. Findings…
Examining Household Asthma Management Behavior through a Microeconomic Framework
ERIC Educational Resources Information Center
Magzamen, Sheryl; Brandt, Sylvia J.; Tager, Ira B.
2014-01-01
National guidelines on the effective management of pediatric asthma have been promoted for over 20 years, yet asthma-related morbidity among low-income children remains disproportionately high. To date, household and clinical interventions designed to remediate these differences have been informed largely by a health behavior framework. However,…
The role of gtcA in the pathogenesis of gastrointestinal listeriosis
USDA-ARS?s Scientific Manuscript database
Serotype 4b strains of Listeria monocytogenes have been implicated in most large outbreaks of listeriosis. The reason for this relationship remains unclear. The gtcA gene is required for glycosylation of teichoic acid on serotype 4b L. monocytogenes. In this study, we investigated two different sero...
Young People's Perceptions of Advice about Sexual Risk Taking
ERIC Educational Resources Information Center
Donoghue, Christopher; Bonillas, Consuelo; Moreno, Jeniffer; Cardoza, Omara; Cheung, Melissa
2017-01-01
Sexual and reproductive health indicators for young people in the USA have improved in recent decades, but teenage pregnancies remain high, and large differences between Whites and non-Whites persist in teenage births, abortions, and the acquisition of sexually transmitted infections. Prior research shows that young people are receptive to…
From Compassionate Ageism to Intergenerational Conflict?
ERIC Educational Resources Information Center
Binstock, Robert H.
2010-01-01
During the 50 years in which "The Gerontologist" has been publishing, the politics of aging in the United States has undergone distinct changes. The political behavior of older individuals has remained largely the same even though different birth cohorts have succeeded each other in populating the ranks of older people. But the politics…
Meijer, Hanneke J. M.; Rossi, Maria Adelaide; Göhlich, Ursula B.
2017-01-01
New skeletal elements of the recently described endemic giant anseriform Garganornis ballmanni Meijer, 2014 are presented, coming from the type-area of the Gargano and from Scontrone, southern and central Italy, respectively. The new remains represent the first bird remains found at Scontrone so far, and another shared element between these two localities, both part of the Apulia-Abruzzi Palaeobioprovince. The presence of a very reduced carpometacarpus confirms its flightlessness, only previously supposed on the basis of the very large size, while the morphologies of tarsometatarsus and posterior phalanges clearly indicate the adaptation of G. ballmanni to a terrestrial, non-aquatic, lifestyle. Its very large body size is similar to that observed in different, heavily modified, insular waterfowl and has been normally interpreted as the response to the absence of terrestrial predators and a protection from the aerial ones. The presence of a carpal knob in the proximal carpometacarpus also indicates a fighting behaviour for this large terrestrial bird species. PMID:28280574
NASA Astrophysics Data System (ADS)
Reilly, David; Neumann, David L.; Andrews, Glenda
2017-06-01
The underrepresentation of women in science, technology, engineering, and mathematics (STEM)-related fields remains a concern for educators and the scientific community. Gender differences in mathematics and science achievement play a role, in conjunction with attitudes and self-efficacy beliefs. We report results from the 2011 Trends in Mathematics and Science Study (TIMSS), a large international assessment of eighth grade students' achievement, attitudes, and beliefs among 45 participating nations (N = 261,738). Small- to medium-sized gender differences were found for most individual nations (from d = -.60 to +.31 in mathematics achievement, and d = -.60 to +.26 for science achievement), although the direction varied and there were no global gender differences overall. Such a pattern cross-culturally is incompatible with the notion of immutable gender differences. Additionally, there were different patterns between OECD and non-OECD nations, with girls scoring higher than boys in mathematics and science achievement across non-OECD nations. An association was found between gender differences in science achievement and national levels of gender equality, providing support for the gender segregation hypothesis. Furthermore, the performance of boys was more variable than that of girls in most nations, consistent with the greater male variability hypothesis. Boys reported more favorable attitudes towards mathematics and science, and girls reported lower self-efficacy beliefs. While the gender gap in STEM achievement may be closing, there are still large sections of the world where differences remain.
NASA Astrophysics Data System (ADS)
Ruiz-Villanueva, Virginia; Piégay, Hervé; Gurnell, Angela A.; Marston, Richard A.; Stoffel, Markus
2016-09-01
Large wood is an important physical component of woodland rivers and significantly influences river morphology. It is also a key component of stream ecosystems. However, large wood is also a source of risk for human activities as it may damage infrastructure, block river channels, and induce flooding. Therefore, the analysis and quantification of large wood and its mobility are crucial for understanding and managing wood in rivers. As the amount of large-wood-related studies by researchers, river managers, and stakeholders increases, documentation of commonly used and newly available techniques and their effectiveness has also become increasingly relevant as well. Important data and knowledge have been obtained from the application of very different approaches and have generated a significant body of valuable information representative of different environments. This review brings a comprehensive qualitative and quantitative summary of recent advances regarding the different processes involved in large wood dynamics in fluvial systems including wood budgeting and wood mechanics. First, some key definitions and concepts are introduced. Second, advances in quantifying large wood dynamics are reviewed; in particular, how measurements and modeling can be combined to integrate our understanding of how large wood moves through and is retained within river systems. Throughout, we present a quantitative and integrated meta-analysis compiled from different studies and geographical regions. Finally, we conclude by highlighting areas of particular research importance and their likely future trajectories, and we consider a particularly underresearched area so as to stress the future challenges for large wood research.
Histological Comparison of Cold versus Hot Snare Resections of the Colorectal Mucosa.
Takayanagi, Daisuke; Nemoto, Daiki; Isohata, Noriyuki; Endo, Shungo; Aizawa, Masato; Utano, Kenichi; Kumamoto, Kensuke; Hojo, Hiroshi; Lefor, Alan Kawarai; Togashi, Kazutomo
2018-06-25
Delayed postpolypectomy bleeding occurs more frequently after hot resection than after cold resection. To elucidate the underlying mechanism, we performed a histological comparison of tissue after cold and hot snare resections. This is a prospective study, registered in the University Hospital Medical Information Network (UMIN000020104). This study was conducted at Aizu Medical Center, Fukushima Medical University, Japan. Fifteen patients scheduled to undergo resection of colorectal cancer were enrolled. On the day before surgery, 2 mucosal resections (hot and cold) of normal mucosa were performed on each patient using the same snare without saline injection. The difference was only the application of electrocautery or not. Resection sites were placed close to the cancer to be included in the surgical specimen. The primary outcome measure was the depth of destruction. Secondary outcome measures included the width of destruction, depth of the remaining submucosa, and number of vessels remaining at the resection sites. The number and diameter of vessels in undamaged submucosa were also evaluated. All cold resections were limited to the shallow submucosa, whereas 60% of hot resections advanced to the deep submucosa and 20% to the muscularis propria (p < 0.001). There was no significant difference in the width of destruction. The number of remaining large vessels after hot resections trended toward fewer (p = 0.15) with a decreased depth of remaining submucosa (p = 0.007). In the deep submucosa, the vessel diameter was larger (p < 0.001) and the number of large vessels was greater (p = 0.018). Histological assessment was not blinded to the 2 reviewers. Normal mucosa was used instead of adenomatous tissue. Hot resection caused damage to deeper layers involving more large vessels. This may explain the mechanism for the reduced incidence of hemorrhage after cold snare polypectomy. See Video Abstract at http://links.lww.com/DCR/A631.
Thirty years of Alzheimer's disease genetics: the implications of systematic meta-analyses.
Bertram, Lars; Tanzi, Rudolph E
2008-10-01
The genetic underpinnings of Alzheimer's disease (AD) remain largely elusive despite early successes in identifying three genes that cause early-onset familial AD (those that encode amyloid precursor protein (APP) and the presenilins (PSEN1 and PSEN2)), and one genetic risk factor for late-onset AD (the gene that encodes apolipoprotein E (APOE)). A large number of studies that aimed to help uncover the remaining disease-related loci have been published in recent decades, collectively proposing or refuting the involvement of over 500 different gene candidates. Systematic meta-analyses of these studies currently highlight more than 20 loci that have modest but significant effects on AD risk. This Review discusses the putative pathogenetic roles and common biochemical pathways of some of the most genetically and biologically compelling of these potential AD risk factors.
NASA Astrophysics Data System (ADS)
Ugan, Andrew; Byers, David
2007-12-01
The causes of large animal extinctions at the end of the Pleistocene remain a hotly debated topic focused primarily on the effects of human over hunting and climate change. Here we examine multiple, large radiocarbon data sets for humans and extinct proboscideans and explore how variation in their temporal and geographic distributions were related prior to proboscidean extinction. These data include 4532 archaeological determinations from Europe and Siberia and 1177 mammoth and mastodont determinations from Europe, Siberia, and North America. All span the period from 45,000 to 12,000 calendar years BP. We show that while the geographic ranges of dated human occupations and proboscidean remains overlap across the terminal Pleistocene of the Old World, the two groups remain largely segregated and increases in the frequency of human occupations do not coincide with declines in proboscidean remains. Prior to the Last Glacial Maximum (LGM; ca 21,000 years BP), archaeological 14C determinations increase slightly in frequency worldwide while the frequency of dated proboscidean remains varies depending on taxon and location. After the LGM, both sympatric and allopatric groups of humans and proboscideans increase sharply as climatic conditions ameliorate. Post-LGM radiocarbon frequencies among proboscideans peak at different times, also depending upon taxon and location. Woolly mammoths in Beringia reach a maximum and then decline beginning between 16,000 and 15,500 years BP, woolly mammoths in Europe and Siberia ca 14,500 and 13,500 BP, and Columbian mammoth and American mastodont only after 13,000 BP. Declines among woolly mammoths appear to coincide with the restructuring of biotic communities following the Pleistocene-Holocene transition.
Comparison of decomposition rates between autopsied and non-autopsied human remains.
Bates, Lennon N; Wescott, Daniel J
2016-04-01
Penetrating trauma has been cited as a significant factor in the rate of decomposition. Therefore, penetrating trauma may have an effect on estimations of time-since-death in medicolegal investigations and on research examining decomposition rates and processes when autopsied human bodies are used. The goal of this study was to determine if there are differences in the rate of decomposition between autopsied and non-autopsied human remains in the same environment. The purpose is to shed light on how large incisions, such as those from a thorocoabdominal autopsy, effect time-since-death estimations and research on the rate of decomposition that use both autopsied and non-autopsied human remains. In this study, 59 non-autopsied and 24 autopsied bodies were studied. The number of accumulated degree days required to reach each decomposition stage was then compared between autopsied and non-autopsied remains. Additionally, both types of bodies were examined for seasonal differences in decomposition rates. As temperature affects the rate of decomposition, this study also compared the internal body temperatures of autopsied and non-autopsied remains to see if differences between the two may be leading to differential decomposition. For this portion of this study, eight non-autopsied and five autopsied bodies were investigated. Internal temperature was collected once a day for two weeks. The results showed that differences in the decomposition rate between autopsied and non-autopsied remains was not statistically significant, though the average ADD needed to reach each stage of decomposition was slightly lower for autopsied bodies than non-autopsied bodies. There was also no significant difference between autopsied and non-autopsied bodies in the rate of decomposition by season or in internal temperature. Therefore, this study suggests that it is unnecessary to separate autopsied and non-autopsied remains when studying gross stages of human decomposition in Central Texas and that penetrating trauma may not be a significant factor in the overall rate of decomposition. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Migration, Trauma, PTSD: A Gender Study in Morrison's Jazz
ERIC Educational Resources Information Center
Motlagh, Leila Tafreshi; Yahya, Wan Roselezam Wan
2014-01-01
Toni Morrison is an acknowledged master of trauma literature, however trauma theory and a gender response to trauma remain largely unaccounted for her migration literature, specifically "Jazz" (1992). In her novel, two migrant women are affected by the same trauma, a crime of passion. But they choose different reactions and coping…
Developmental Changes in the Primacy of Facial Cues for Emotion Recognition
ERIC Educational Resources Information Center
Leitzke, Brian T.; Pollak, Seth D.
2016-01-01
There have been long-standing differences of opinion regarding the influence of the face relative to that of contextual information on how individuals process and judge facial expressions of emotion. However, developmental changes in how individuals use such information have remained largely unexplored and could be informative in attempting to…
Recent human history governs global ant invasion dynamics
Cleo Bertelsmeier; Sébastien Ollier; Andrew Liebhold; Laurent Keller
2017-01-01
Human trade and travel are breaking down biogeographic barriers, resulting in shifts in the geographical distribution of organisms, yet it remains largely unknown whether different alien species generally follow similar spatiotemporal colonization patterns and how such patterns are driven by trends in global trade. Here, we analyse the global distribution of 241 alien...
Social and Psychiatric Influences on Urban-Rural Differentials in Australian Suicide
ERIC Educational Resources Information Center
Taylor, Richard; Page, Andrew; Morrell, Stephen; Harrison, James; Carter, Greg
2005-01-01
The purpose of this study was to investigate urban-rural differentials in Australian suicide rates, and to examine influences that previously have remained largely speculative. Suicide rates for males (all ages and young adults) were significantly higher in rural areas compared to urban areas. Urban-rural suicide rate differences in males were…
Standardization of Selected Semantic Differential Scales with Secondary School Children.
ERIC Educational Resources Information Center
Evans, G. T.
A basic assumption of this study is that the meaning continuum registered by an adjective pair remains relatively constant over a large universe of concepts and over subjects within a relatively homogeneous population. An attempt was made to validate this assumption by showing the invariance of the factor structure across different types of…
Screening for Scoliosis: Different Countries' Perspectives and Evidence-Based Health Care
ERIC Educational Resources Information Center
Plaszewski, Maciej; Nowobilski, Roman; Kowalski, Pawel; Cieslinski, Maciej
2012-01-01
Idiopathic scoliosis affects 2-3% of adolescents. Large, progressing deformities, mostly present in girls, may lead to pulmonary complications, pain symptoms, the feeling of social isolation, and even mental disorders. The correlation of screening programs with surgery rate reduction and the clinical effectiveness of bracing remain a matter of…
ERIC Educational Resources Information Center
Connor, Daniel F.; Doerfler, Leonard A.
2008-01-01
Objective: In children with ADHD who have comorbid disruptive behavior diagnoses distinctions between oppositional defiant disorder (ODD) and conduct disorder (CD) remain unclear. The authors investigate differences between ODD and CD in a large clinical sample of children with ADHD. Method: Consecutively referred and systematically assessed male…
Patients "Embodied" and "As-a-Body" within Bedside Teaching Encounters: A Video Ethnographic Study
ERIC Educational Resources Information Center
Elsey, Christopher; Challinor, Alexander; Monrouxe, Lynn V.
2017-01-01
Bedside teaching encounters (BTEs) involve doctor-patient-student interactions, providing opportunities for students to learn with, from and about patients. How the differing concerns of patient care and student education are balanced in situ remains largely unknown and undefined. This video ethnographic study explores "patient…
Bricks-and-mortar and patient safety culture.
Brandis, Susan; Schleimer, Stephanie; Rice, John
2017-06-19
Purpose Building a new hospital requires a major investment in capital infrastructure. The purpose of this paper is to investigate the impact of bricks-and-mortar on patient safety culture before and two years after the move of a large tertiary hospital to a greenfield site. The difference in patient safety perceptions between clinical and non-clinical staff is also explored. Design/methodology/approach This research uses data collected from the same workforce across two time periods (2013 and 2015) in a large Australian healthcare service. Validated surveys of patient safety culture ( n=306 and 246) were analysed using descriptive and inferential statistics. Findings Using two-way analysis of variance, the authors found that perceived patient safety culture remains unchanged for staff despite a major relocation and upgrade of services and different perceptions of patient safety culture between staff groups remains the same throughout change. Practical implications A dramatic change in physical context, such as moving an entire hospital, made no measurable impact on perceived patient safety culture by major groups of staff. Improving patient safety culture requires more than investment in buildings and infrastructure. Understanding differences in professional perspectives of patient safety culture may inform organisational management approaches, and enhance the targeting of specific strategies. Originality/value The authors believe this to be the first empirically based paper that investigates the impact of a large investment into hospital capital and a subsequent relocation of services on clinical and non-clinical staff perceptions of patient safety culture.
Type II Heat-labile Enterotoxins: Structure, Function, and Immunomofdulatory Properties
Hajishengallis, George; Connell, Terry D.
2012-01-01
The heat-labile enterotoxins (HLTs) of Escherichia coli and Vibrio cholerae are classified into two major types on the basis of genetic, biochemical, and immunological properties. Type I and Type II HLT have been intensively studied for their exceptionally strong adjuvant activities. Despite general structural similarities, these molecules, in intact or derivative (non-toxic) forms, display notable differences in their mode of immunomodulatory action. The molecular basis of these differences has remained largely uncharacterized until recently. This review focuses on the Type II HLTs and their immunomodulatory properties which depend largely on interactions with unique gangliosides and Toll-like receptors that are not utilized by the Type I HLTs. PMID:23137790
Xie, Rou-Gang; Chu, Wen-Guang; Hu, San-Jue; Luo, Ceng
2018-01-01
Sensory neuron types have been distinguished by distinct morphological and transcriptional characteristics. Excitability is the most fundamental functional feature of neurons. Mathematical models described by Hodgkin have revealed three types of neuronal excitability based on the relationship between firing frequency and applied current intensity. However, whether natural sensory neurons display different functional characteristics in terms of excitability and whether this excitability type undergoes plastic changes under pathological pain states have remained elusive. Here, by utilizing whole-cell patch clamp recordings, behavioral and pharmacological assays, we demonstrated that large dorsal root ganglion (DRG) neurons can be classified into three classes and four subclasses based on their excitability patterns, which is similar to mathematical models raised by Hodgkin. Analysis of hyperpolarization-activated cation current (Ih) revealed different magnitude of Ih in different excitability types of large DRG neurons, with higher Ih in Class 2-1 than that in Class 1, 2-2 and 3. This indicates a crucial role of Ih in the determination of excitability type of large DRG neurons. More importantly, this pattern of excitability displays plastic changes and transition under pathological pain states caused by peripheral nerve injury. This study sheds new light on the functional characteristics of large DRG neurons and extends functional classification of large DRG neurons by integration of transcriptomic and morphological characteristics. PMID:29303989
The mobility gap between older men and women: the embodiment of gender.
Zunzunegui, M V; Alvarado, B E; Guerra, R; Gómez, J F; Ylli, A; Guralnik, J M
2015-01-01
To present the study design and baseline results of the longitudinal International Mobility in Aging Study (IMIAS) on gender differences in physical performance and mobility disability prevalence in five diverse societies. Data are from surveys on random samples of people aged 65-74 years at Canadian (Kingston, Ontario; Saint-Hyacinthe, Quebec), Mediterranean (Tirana, Albania) and Latin American sites (Natal, Brazil; Manizales, Colombia) (N=1995). Mobility disability was defined as reporting difficulty in walking 400m or climbing stairs. Activities of daily living (ADL) disability was based on any self-reported difficulty in five mobility-related ADLs. The short physical performance battery (SPPB) was used to assess physical performance. Poisson regression models were fitted to estimate prevalence ratios. Age-adjusted prevalence of low SPPB, mobility disability and ADL disability were higher in women than in men in all sites except for Kingston. After adjustment for education and income, gender differences in SPPB and ADL disability attenuated or disappeared in Saint-Hyacinthe and Manizales but remained large in Tirana and Natal and mobility disability remained more frequent in women than in men at all sites except Kingston. After further adjustment by chronic conditions and depressive symptoms, gender differences in mobility remained large at all sites except Kingston but only in Tirana did women have significantly poorer physical performance than men. Results provide evidence for gender as a risk factor to explain poorer physical function in women and suggest that moving toward gender equality could attenuate the gender gap in physical function in old age. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Antman, Karen
2002-01-01
High dose therapy for breast cancer remains controversial. Of the 15 randomized trials of high dose therapy in breast cancer reported to date, two South African studies have been discredited leaving 13 remaining studies. Mortality was consistently low, in the 0 to 2.5% range, except for the BCNU containing American Intergroup study, which had a 7.4% toxic mortality rate. Seven of the remaining 13 studies randomized fewer than 200 patients. Three of these small studies have significant differences in disease free survival, and a fourth study has a trend in favor of high dose therapy. The other three small studies cannot exclude a survival difference of 20%. Of the 6 remaining moderately large trials of 219 to 885 randomized patients, 5 are adjuvant studies and one included patients with metastatic disease. Of the five adjuvant trials, four have significant differences in relapse rate favoring the high dose arm, and the remaining study has a trend (with a high dose sequential single agent design rather than combination therapy as in the other studies). A planned subset analysis of the first 284 patients in the largest study funded by the Dutch insurance industry showed a significant advantage for high dose therapy. Given the 2-year median time to relapse and an addition 2-year median to death after relapse, the follow up for survival of 3-5 years on these studies is still short. In the only moderately sized metastatic trial from the National Cancer Institute of Canada with a very short median follow-up of 19 months, a significant difference in disease free survival has emerged, with no difference in survival. PMID:12053718
Antman, Karen
2002-01-01
High dose therapy for breast cancer remains controversial. Of the 15 randomized trials of high dose therapy in breast cancer reported to date, two South African studies have been discredited leaving 13 remaining studies. Mortality was consistently low, in the 0 to 2.5% range, except for the BCNU containing American Intergroup study, which had a 7.4% toxic mortality rate. Seven of the remaining 13 studies randomized fewer than 200 patients. Three of these small studies have significant differences in disease free survival, and a fourth study has a trend in favor of high dose therapy. The other three small studies cannot exclude a survival difference of 20%. Of the 6 remaining moderately large trials of 219 to 885 randomized patients, 5 are adjuvant studies and one included patients with metastatic disease. Of the five adjuvant trials, four have significant differences in relapse rate favoring the high dose arm, and the remaining study has a trend (with a high dose sequential single agent design rather than combination therapy as in the other studies). A planned subset analysis of the first 284 patients in the largest study funded by the Dutch insurance industry showed a significant advantage for high dose therapy. Given the 2-year median time to relapse and an addition 2-year median to death after relapse, the follow up for survival of 3-5 years on these studies is still short. In the only moderately sized metastatic trial from the National Cancer Institute of Canada with a very short median follow-up of 19 months, a significant difference in disease free survival has emerged, with no difference in survival.
Large eddy simulation applications in gas turbines.
Menzies, Kevin
2009-07-28
The gas turbine presents significant challenges to any computational fluid dynamics techniques. The combination of a wide range of flow phenomena with complex geometry is difficult to model in the context of Reynolds-averaged Navier-Stokes (RANS) solvers. We review the potential for large eddy simulation (LES) in modelling the flow in the different components of the gas turbine during a practical engineering design cycle. We show that while LES has demonstrated considerable promise for reliable prediction of many flows in the engine that are difficult for RANS it is not a panacea and considerable application challenges remain. However, for many flows, especially those dominated by shear layer mixing such as in combustion chambers and exhausts, LES has demonstrated a clear superiority over RANS for moderately complex geometries although at significantly higher cost which will remain an issue in making the calculations relevant within the design cycle.
Reduced oxygen at high altitude limits maximum size.
Peck, L S; Chapelle, G
2003-11-07
The trend towards large size in marine animals with latitude, and the existence of giant marine species in polar regions have long been recognized, but remained enigmatic until a recent study showed it to be an effect of increased oxygen availability in sea water of a low temperature. The effect was apparent in data from 12 sites worldwide because of variations in water oxygen content controlled by differences in temperature and salinity. Another major physical factor affecting oxygen content in aquatic environments is reduced pressure at high altitude. Suitable data from high-altitude sites are very scarce. However, an exceptionally rich crustacean collection, which remains largely undescribed, was obtained by the British 1937 expedition from Lake Titicaca on the border between Peru and Bolivia in the Andes at an altitude of 3809 m. We show that in Lake Titicaca the maximum length of amphipods is 2-4 times smaller than other low-salinity sites (Caspian Sea and Lake Baikal).
Adult Learning--Providing Equal Opportunities or Widening Differences? The Polish Case
ERIC Educational Resources Information Center
Kocór, Marcin; Worek, Barbara
2017-01-01
Educational activity among adults is not only a key factor of social development but also one of the most important priorities of public policies. Although large sums have been earmarked and numerous actions undertaken to encourage adult learning, many people remain educationally passive, a particularly acute problem in Poland. We point to the…
Designs for Operationalizing Collaborative Problem Solving for Automated Assessment
ERIC Educational Resources Information Center
Scoular, Claire; Care, Esther; Hesse, Friedrich W.
2017-01-01
Collaborative problem solving is a complex skill set that draws on social and cognitive factors. The construct remains in its infancy due to lack of empirical evidence that can be drawn upon for validation. The differences and similarities between two large-scale initiatives that reflect this state of the art, in terms of underlying assumptions…
The Impact of Achievement Goals on Cardiorespiratory Fitness: Does Self-Efficacy Make a Difference?
ERIC Educational Resources Information Center
Gao, Zan; Xiang, Ping; Lochbaum, Marc; Guan, Jianmin
2013-01-01
Purpose: The relationships among students' self-efficacy, 2 × 2 achievement goals (mastery-approach [MAp], mastery-avoidance [MAv], performance-approach [PAp], and performance-avoidance goals), and achievement performance remain largely unanswered. We tested a model of the mediating role of self-efficacy on the relationship between 2 × 2…
Samuel M. Simkin; Edith B. Allen; William D. Bowman; Christopher M. Clark; Jayne Belnap; Matthew L. Brooks; Brian S. Cade; Scott L. Collins; Linda H. Geiser; Frank S. Gilliam; Sarah E. Jovan; Linda H. Pardo; Bethany K. Schulz; Carly J. Stevens; Katharine N. Suding; Heather L. Throop; Donald M. Waller
2016-01-01
Atmospheric nitrogen (N) deposition has been shown to decrease plant species richness along regional deposition gradients in Europe and in experimental manipulations. However, the general response of species richness to N deposition across different vegetation types, soil conditions, and climates remains largely unknown even though responses may be contingent on these...
ERIC Educational Resources Information Center
van Hek, Margriet; Kraaykamp, Gerbert; Wolbers, Maarten H. J.
2016-01-01
Nowadays, women outperform men in educational attainment in many countries. Still, large variation between countries remains. Emancipatory contexts in which individuals are raised might explain these differences in male-female educational attainment, both over time and across countries. This study examines individual and contextual factors that…
A Qatari Perspective on Women in the Engineering Pipeline: An Exploratory Study
ERIC Educational Resources Information Center
Sulaiman, Noor Fauziah; AlMuftah, Hend
2010-01-01
Under-representation of women in engineering has received a great deal of attention, but remained limited largely to a Western context. Thus, this article aims to unveil the barriers to progress, tracking the performance and the emerging trend of success at the undergraduate level of women in engineering in a different cultural dimension.…
ERIC Educational Resources Information Center
Esler, Amy N.; Hall-Lande, Jennifer; Hewitt, Amy
2017-01-01
The potential for culture to impact diagnosis of autism spectrum disorder (ASD) is high, yet remains largely unstudied. This study examined differences across racial/ethnic groups in ASD symptoms, cognitive and adaptive skills, and related behaviors in children with ASD that included a unique subgroup, children from the Somali diaspora. Somali…
ERIC Educational Resources Information Center
Brooker, Rebecca J.; Buss, Kristin A.; Lemery-Chalfant, Kathryn; Aksan, Nazan; Davidson, Richard J.; Goldsmith, H. Hill
2013-01-01
Despite implications that stranger fear is an important aspect of developing behavioral inhibition, a known risk factor for anxiety, normative and atypical developmental trajectories of stranger fear across infancy and toddlerhood remain understudied. We used a large, longitudinal data set (N = 1285) including multi-trait, multi-method assessments…
ERIC Educational Resources Information Center
Brennan, Christine; Booth, James R.
2015-01-01
Linguistic knowledge, cognitive ability, and instruction influence how adults acquire a second orthography yet it remains unclear how different forms of instruction influence grain size sensitivity and subsequent decoding skill and speed. Thirty-seven monolingual, literate English-speaking adults were trained on a novel artificial orthography…
Methods for control of tick vectors of Lyme Borreliosis
Jaenson, T.G.T.; Fish, D.; Ginsberg, H.S.; Gray, J.S.; Mather, T.N.; Piesman, J.
1991-01-01
During the IVth International Conference on Lyme Borreliosis in Stockholm, 1990, a workshop on control of Lyme disease vectors briefly reviewed: basic ecological principles for tick control; biocontrol of ticks; chemical control, including the use of repellents and use of permethrin-treated rodent nest material; tick control by habitat modification; and reduction of tick host availability. It was concluded that, although much research work remains, Lyme borreliosis is to a large extent a preventable infection. Avoidance of heavily tick-infested areas, personal protection using proper clothing, and prompt removal of attached ticks remain the most effective protective measures. Many other prophylactic measures are available and could be efficiently integrated into schemes to reduce the abundance of vectors. However, since the ecology of the infection varies greatly between different localities it may be necessary to apply different combinations of control methods in different endemic regions.
Brouwer, Andrew F; Masters, Nina B; Eisenberg, Joseph N S
2018-04-20
Waterborne enteric pathogens remain a global health threat. Increasingly, quantitative microbial risk assessment (QMRA) and infectious disease transmission modeling (IDTM) are used to assess waterborne pathogen risks and evaluate mitigation. These modeling efforts, however, have largely been conducted independently for different purposes and in different settings. In this review, we examine the settings where each modeling strategy is employed. QMRA research has focused on food contamination and recreational water in high-income countries (HICs) and drinking water and wastewater in low- and middle-income countries (LMICs). IDTM research has focused on large outbreaks (predominately LMICs) and vaccine-preventable diseases (LMICs and HICs). Human ecology determines the niches that pathogens exploit, leading researchers to focus on different risk assessment research strategies in different settings. To enhance risk modeling, QMRA and IDTM approaches should be integrated to include dynamics of pathogens in the environment and pathogen transmission through populations.
The development of young siblings of children with autism from 4 to 54 months.
Gamliel, Ifat; Yirmiya, Nurit; Sigman, Marian
2007-01-01
Cognitive and language skills of 39 siblings of children with autism (SIBS-A) and 39 siblings of typically developing children (SIBS-TD) at ages 4, 14, 24, 36, and 54 months were compared. Twelve of the 39 SIBS-A revealed a delay in cognition and/or language (including one child diagnosed with autism) compared to only two SIBS-TD. Developmental trajectories revealed that the cognitive differences disappeared by age 54 months, but some differences in language ability remained. Thus, most SIBS-A were well-functioning, but some revealed cognitive and/or language difficulties during the preschool years. Even these siblings by and large caught up by the age of 54 months, with receptive and expressive language abilities remaining an area of difficulty for some earlier identified siblings.
García-Palacios, Pablo; Maestre, Fernando T.; Kattge, Jens; Wall, Diana H.
2015-01-01
Climate and litter quality have been identified as major drivers of litter decomposition at large spatial scales. However, the role played by soil fauna remains largely unknown, despite its importance for litter fragmentation and microbial activity. We synthesized litterbag studies to quantify the effect sizes of soil fauna on litter decomposition rates at the global and biome scales, and to assess how climate, litter quality and soil fauna interact to determine such rates. Soil fauna consistently enhanced litter decomposition at both global and biome scales (average increment ~27%). However, climate and litter quality differently modulated the effects of soil fauna on decomposition rates between biomes, from climate-driven biomes to those where climate effects were mediated by changes in litter quality. Our results advocate for the inclusion of biome-specific soil fauna effects on litter decomposition as a mean to reduce the unexplained variation in large-scale decomposition models. PMID:23763716
Lithologies Making Up CM Carbonaceous Chondrites and Their Link to Space Exposure Ages
NASA Technical Reports Server (NTRS)
Gregory, Timothy; Zolensky, Michael E.; Trieman, Alan; Berger, Eve; Le, Loan; Fagan, Amy; Takenouchi, Atsushi; Velbel, Michael A.; Nishiizumi, Kunihiko
2015-01-01
Chondrite parent bodies are among the first large bodies to have formed in the early Solar System, and have since remained almost chemically unchanged having not grown large enough or quickly enough to undergo differentiation. Their major nonvolatile elements bear a close resemblance to the solar photosphere. Previous work has concluded that CM chondrites fall into at least four distinct space exposure age groups (0.1 Ma, 0.2 Ma, 0.6 Ma and >2.0 Ma), but the meaning of these groupings is unclear. It is possible that these meteorites came from different parent bodies which broke up at different times, or instead came from the same parent body which underwent multiple break-up events, or a combination of these scenarios.
Lithologies Making Up CM Carbonaceous Chondrites and Their Link to Space Exposure Ages
NASA Technical Reports Server (NTRS)
Gregory, Timothy; Zolensky, Michael E.; Trieman, Alan; Berger, Eve; Le, Loan; Fagan, Amy; Takenouchi, Atsushi; Velbel, Michael A.; Nishiizumi, Kuni
2015-01-01
Chondrite parent bodies are among the first large bodies to have formed in the early Solar System, and have since remained almost chemically unchanged having not grown large enough or quickly enough to undergo differentiation. Their major nonvolatile elements bear a close resemblance to the solar photosphere. Previous work has concluded that CM chondrites fall into at least four distinct space exposure age groups (0.1 megaannus, 0.2 megaannus, 0.6 megaannus and 2.0 megaannus), but the meaning of these groupings is unclear. It is possible that these meteorites came from different parent bodies which broke up at different times, or instead came from the same parent body which underwent multiple break-up events, or a combination of these scenarios.
Remote sensing applied to numerical modelling. [water resources pollution
NASA Technical Reports Server (NTRS)
Sengupta, S.; Lee, S. S.; Veziroglu, T. N.; Bland, R.
1975-01-01
Progress and remaining difficulties in the construction of predictive mathematical models of large bodies of water as ecosystems are reviewed. Surface temperature is at present the only variable than can be measured accurately and reliably by remote sensing techniques, but satellite infrared data are of sufficient resolution for macro-scale modeling of oceans and large lakes, and airborne radiometers are useful in meso-scale analysis (of lakes, bays, and thermal plumes). Finite-element and finite-difference techniques applied to the solution of relevant coupled time-dependent nonlinear partial differential equations are compared, and the specific problem of the Biscayne Bay and environs ecosystem is tackled in a finite-differences treatment using the rigid-lid model and a rigid-line grid system.
Giroux, Marie-Andrée; Valiquette, Éliane; Tremblay, Jean-Pierre; Côté, Steeve D
2015-01-01
Documenting habitat-related patterns in foraging behaviour at the individual level and over large temporal scales remains challenging for large herbivores. Stable isotope analysis could represent a valuable tool to quantify habitat-related foraging behaviour at the scale of individuals and over large temporal scales in forest dwelling large herbivores living in coastal environments, because the carbon (δ13C) or nitrogen (δ15N) isotopic signatures of forage can differ between open and closed habitats or between terrestrial and littoral forage, respectively. Here, we examined if we could detect isotopic differences between the different assemblages of forage taxa consumed by white-tailed deer that can be found in open, closed, supralittoral, and littoral habitats. We showed that δ13C of assemblages of forage taxa were 3.0 ‰ lower in closed than in open habitats, while δ15N were 2.0 ‰ and 7.4 ‰ higher in supralittoral and littoral habitats, respectively, than in terrestrial habitats. Stable isotope analysis may represent an additional technique for ecologists interested in quantifiying the consumption of terrestrial vs. marine autotrophs. Yet, given the relative isotopic proximity and the overlap between forage from open, closed, and supralittoral habitats, the next step would be to determine the potential to estimate their contribution to herbivore diet.
Inertia in the Brazil nut problem.
Nahmad-Molinari, Y; Canul-Chay, G; Ruiz-Suárez, J C
2003-10-01
The rise dynamics of a large particle, in a granular bed under vertical vibrations, is experimentally studied with an inductive device designed to track the particle while it climbs through the granulate under different conditions. A model based on energy considerations is presented to explain our experimental data, drawing the important conclusion that it is the inertia of the particle, assisted by Reynolds dilatancy, the driven force behind its ascension mechanism. The ascension reveals a friction profile within the column which remains unchanged for different accelerations.
He, Jing; Yi, Li; Hai, Le; Ming, Liang; Gao, Wanting; Ji, Rimutu
2018-01-12
The bacterial community plays important roles in the gastrointestinal tracts (GITs) of animals. However, our understanding of the microbial communities in the GIT of Bactrian camels remains limited. Here, we describe the bacterial communities from eight different GIT segments (rumen, reticulum, abomasum, duodenum, ileum, jejunum, caecum, colon) and faeces determined from 11 Bactrian camels using 16S rRNA gene amplicon sequencing. Twenty-seven bacterial phyla were found in the GIT, with Firmicutes, Verrucomicrobia and Bacteroidetes predominating. However, there were significant differences in microbial community composition between segments of the GIT. In particular, a greater proportion of Akkermansia and Unclassified Ruminococcaceae were found in the large intestine and faecal samples, while more Unclassified Clostridiales and Unclassified Bacteroidales were present in the in forestomach and small intestine. Comparative analysis of the microbiota from different GIT segments revealed that the microbial profile in the large intestine was like that in faeces. We also predicted the metagenomic profiles for the different GIT regions. In forestomach, there was enrichment associated with replication and repair and amino acid metabolism, while carbohydrate metabolism was enriched in the large intestine and faeces. These results provide profound insights into the GIT microbiota of Bactrian camels.
Pulse thermal energy transport/storage system
Weislogel, Mark M.
1992-07-07
A pulse-thermal pump having a novel fluid flow wherein heat admitted to a closed system raises the pressure in a closed evaporator chamber while another interconnected evaporator chamber remains open. This creates a large pressure differential, and at a predetermined pressure the closed evaporator is opened and the opened evaporator is closed. This difference in pressure initiates fluid flow in the system.
1986-06-01
model of the self-evaluation process as it differs from the evaluation process used by superiors. Symbolic Interactionism One view of self assessment is...supplied by the symbolic interactionists (Cooley, 1902; Head, 1934), who state that self perceptions are generated largely from individuals...disagreements remained even immediately after an appraisal interview in which a great deal of feedback was given. Research on the symbolic interactionist
A Kinetic Study Using Evaporation of Different Types of Hand-Rub Sanitizers
ERIC Educational Resources Information Center
Pinhas, Allan R.
2010-01-01
Alcohol-based hand-rub sanitizers are the types of products that hospital professionals use very often. These sanitizers can be classified into two major groups: those that contain a large quantity of thickener, and thus are a gel, and those that contain a small quantity of thickener, and thus remain a liquid. In an effort to create a laboratory…
NASA Technical Reports Server (NTRS)
Luu, Jane X.
1992-01-01
Activity in distant comets remains a mystery in the sense that we still have no complete theory to explain the various types of activity exhibited by different comets at large distances. This paper explores the factors that should play a role in determining activity in a distant comet, especially in the cases of comet P/Tempel 2, comet Schwassmann-Wachmann 1, and 2060 Chiron.
A study of buried pipeline response to fault movement
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chiou, Y.J.; Chi, S.Y.; Chang, H.Y.
1994-02-01
This study investigates the buried pipeline response to strike slip fault movement. The large deflection pipe crossing the fault zone is modeled as an elastica, while the remaining portion of small deflection pipe is modeled as a semi-infinite beam on elastic foundation. The finite difference method is applied for the numerical solution and the results agree qualitatively with the earlier works.
ERIC Educational Resources Information Center
Kanfiszer, Lucie; Davies, Fran; Collins, Suzanne
2017-01-01
Existing literature exploring autism spectrum disorders within female populations predominantly utilises quantitative methodology. A limited number of small-scale, qualitative studies have explored the experiences of adolescent girls with autism spectrum disorder, but adult women have remained largely unheard. This study aims to broaden the…
Cost effective technologies and renewable substrates for biosurfactants’ production
Banat, Ibrahim M.; Satpute, Surekha K.; Cameotra, Swaranjit S.; Patil, Rajendra; Nyayanit, Narendra V.
2014-01-01
Diverse types of microbial surface active amphiphilic molecules are produced by a range of microbial communities. The extraordinary properties of biosurfactant/bioemulsifier (BS/BE) as surface active products allows them to have key roles in various field of applications such as bioremediation, biodegradation, enhanced oil recovery, pharmaceutics, food processing among many others. This leads to a vast number of potential applications of these BS/BE in different industrial sectors. Despite the huge number of reports and patents describing BS and BE applications and advantages, commercialization of these compounds remain difficult, costly and to a large extent irregular. This is mainly due to the usage of chemically synthesized media for growing producing microorganism and in turn the production of preferred quality products. It is important to note that although a number of developments have taken place in the field of BS industries, large scale production remains economically challenging for many types of these products. This is mainly due to the huge monetary difference between the investment and achievable productivity from the commercial point of view. This review discusses low cost, renewable raw substrates, and fermentation technology in BS/BE production processes and their role in reducing the production cost. PMID:25566213
Pyenson, Nicholas D; Vermeij, Geerat J
2016-07-01
Large consumers have ecological influence disproportionate to their abundance, although this influence in food webs depends directly on productivity. Evolutionary patterns at geologic timescales inform expectations about the relationship between consumers and productivity, but it is very difficult to track productivity through time with direct, quantitative measures. Based on previous work that used the maximum body size of Cenozoic marine invertebrate assemblages as a proxy for benthic productivity, we investigated how the maximum body size of Cenozoic marine mammals, in two feeding guilds, evolved over comparable temporal and geographical scales. First, maximal size in marine herbivores remains mostly stable and occupied by two different groups (desmostylians and sirenians) over separate timeframes in the North Pacific Ocean, while sirenians exclusively dominated this ecological mode in the North Atlantic. Second, mysticete whales, which are the largest Cenozoic consumers in the filter-feeding guild, remained in the same size range until a Mio-Pliocene onset of cetacean gigantism. Both vertebrate guilds achieved very large size only recently, suggesting that different trophic mechanisms promoting gigantism in the oceans have operated in the Cenozoic than in previous eras. © 2016 The Authors.
Snowdon, John; Chen, Ying-Yeh; Zhong, Baoliang; Yamauchi, Takashi
2018-01-01
Suicide data relating to 1979-2014 were obtained from three East Asian jurisdictions (Taiwan, Hong Kong, Japan) and two 'Western' countries (Australia, New Zealand). Rates and age patterns of suicide have changed markedly since 1979. Graphs of these patterns largely remained either upward-sloping, bimodal or flat (uniform) over the 36 years, male commonly differing from female, and East Asian patterns more like each other than those of the Western countries. Japan's male middle-aged suicide rate reached a peak in 1999-2003, which, like increased rates among working age males in Hong Kong and Taiwan, has been attributed largely to consequences of Asian financial crises. Male to female ratios of suicide rates have remained higher in the Western countries, but late life suicide rates have decreased to varying extents in all five jurisdictions. Identifying reasons for differences between jurisdictions in their suicide rates and patterns at particular times, and over time, is likely to point to factors (period, cohort, psychosocial or cultural) that protect against or foster suicidal ideation. This avenue of research may assist in identifying ways of preventing suicide. Copyright © 2017. Published by Elsevier B.V.
NASA Astrophysics Data System (ADS)
Fouquet, Meddy; Pisanski, Katarzyna; Mathevon, Nicolas; Reby, David
2016-10-01
Voice pitch (the perceptual correlate of fundamental frequency, F0) varies considerably even among individuals of the same sex and age, communicating a host of socially and evolutionarily relevant information. However, due to the almost exclusive utilization of cross-sectional designs in previous studies, it remains unknown whether these individual differences in voice pitch emerge before, during or after sexual maturation, and whether voice pitch remains stable into adulthood. Here, we measured the F0 parameters of men who were recorded once every 7 years from age 7 to 56 as they participated in the British television documentary Up Series. Linear mixed models revealed significant effects of age on all F0 parameters, wherein F0 mean, minimum, maximum and the standard deviation of F0 showed sharp pubertal decreases between age 7 and 21, yet remained remarkably stable after age 28. Critically, men's pre-pubertal F0 at age 7 strongly predicted their F0 at every subsequent adult age, explaining up to 64% of the variance in post-pubertal F0. This finding suggests that between-individual differences in voice pitch that are known to play an important role in men's reproductive success are in fact largely determined by age 7, and may therefore be linked to prenatal and/or pre-pubertal androgen exposure.
Even subtle cultural differences affect face tuning.
Pavlova, Marina A; Heiz, Julie; Sokolov, Alexander N; Fallgatter, Andreas J; Barisnikov, Koviljka
2018-01-01
Culture shapes social cognition in many ways. Yet cultural impact on face tuning remains largely unclear. Here typically developing females and males from the French-speaking part of Switzerland were presented with a set of Arcimboldo-like Face-n-Food images composed of food ingredients and in different degree resembling a face. The outcome had been compared with previous findings obtained in young adults of the South-West Germany. In that study, males exhibit higher thresholds for face tuning on the Face-n-Food task than females. In Swiss participants, no gender differences exist in face tuning. Strikingly, males from the French-speaking part of Switzerland possess higher sensitivity to faces than their German peers, whereas no difference in face tuning occurs between females. The outcome indicates that even relatively subtle cultural differences as well as culture by gender interaction can modulate social cognition. Clarification of the nature of cultural impact on face tuning as well as social cognition at large is of substantial value for understanding a wide range of neuropsychiatric and neurodevelopmental conditions.
An Ancestral Recombination Graph for Diploid Populations with Skewed Offspring Distribution
Birkner, Matthias; Blath, Jochen; Eldon, Bjarki
2013-01-01
A large offspring-number diploid biparental multilocus population model of Moran type is our object of study. At each time step, a pair of diploid individuals drawn uniformly at random contributes offspring to the population. The number of offspring can be large relative to the total population size. Similar “heavily skewed” reproduction mechanisms have been recently considered by various authors (cf. e.g., Eldon and Wakeley 2006, 2008) and reviewed by Hedgecock and Pudovkin (2011). Each diploid parental individual contributes exactly one chromosome to each diploid offspring, and hence ancestral lineages can coalesce only when in distinct individuals. A separation-of-timescales phenomenon is thus observed. A result of Möhle (1998) is extended to obtain convergence of the ancestral process to an ancestral recombination graph necessarily admitting simultaneous multiple mergers of ancestral lineages. The usual ancestral recombination graph is obtained as a special case of our model when the parents contribute only one offspring to the population each time. Due to diploidy and large offspring numbers, novel effects appear. For example, the marginal genealogy at each locus admits simultaneous multiple mergers in up to four groups, and different loci remain substantially correlated even as the recombination rate grows large. Thus, genealogies for loci far apart on the same chromosome remain correlated. Correlation in coalescence times for two loci is derived and shown to be a function of the coalescence parameters of our model. Extending the observations by Eldon and Wakeley (2008), predictions of linkage disequilibrium are shown to be functions of the reproduction parameters of our model, in addition to the recombination rate. Correlations in ratios of coalescence times between loci can be high, even when the recombination rate is high and sample size is large, in large offspring-number populations, as suggested by simulations, hinting at how to distinguish between different population models. PMID:23150600
Evaluating gender similarities and differences using metasynthesis.
Zell, Ethan; Krizan, Zlatan; Teeter, Sabrina R
2015-01-01
Despite the common lay assumption that males and females are profoundly different, Hyde (2005) used data from 46 meta-analyses to demonstrate that males and females are highly similar. Nonetheless, the gender similarities hypothesis has remained controversial. Since Hyde's provocative report, there has been an explosion of meta-analytic interest in psychological gender differences. We utilized this enormous collection of 106 meta-analyses and 386 individual meta-analytic effects to reevaluate the gender similarities hypothesis. Furthermore, we employed a novel data-analytic approach called metasynthesis (Zell & Krizan, 2014) to estimate the average difference between males and females and to explore moderators of gender differences. The average, absolute difference between males and females across domains was relatively small (d = 0.21, SD = 0.14), with the majority of effects being either small (46%) or very small (39%). Magnitude of differences fluctuated somewhat as a function of the psychological domain (e.g., cognitive variables, social and personality variables, well-being), but remained largely constant across age, culture, and generations. These findings provide compelling support for the gender similarities hypothesis, but also underscore conditions under which gender differences are most pronounced. PsycINFO Database Record (c) 2015 APA, all rights reserved.
Large protein as a potential target for use in rabies diagnostics.
Santos Katz, I S; Dias, M H; Lima, I F; Chaves, L B; Ribeiro, O G; Scheffer, K C; Iwai, L K
Rabies is a zoonotic viral disease that remains a serious threat to public health worldwide. The rabies lyssavirus (RABV) genome encodes five structural proteins, multifunctional and significant for pathogenicity. The large protein (L) presents well-conserved genomic regions, which may be a good alternative to generate informative datasets for development of new methods for rabies diagnosis. This paper describes the development of a technique for the identification of L protein in several RABV strains from different hosts, demonstrating that MS-based proteomics is a potential method for antigen identification and a good alternative for rabies diagnosis.
Chittiprol, Seetharamaiah; Chen, Phylip; Petrovic-Djergovic, Danica; Eichler, Tad
2011-01-01
The state-of-the-art cultured podocyte is conditionally immortalized by expression of a temperature-sensitive mutant of the SV40 large-T antigen. These cultures proliferate at 33°C and differentiate at 37°C into arborized cells that more closely resemble in vivo podocytes. However, the degree of resemblance remains controversial. In this study, several parameters were measured in podocyte cell lines derived from mouse (JR, KE), human (MS), and rat (HK). In all lines, the quantities of NEPH1 and podocin proteins and NEPH1 and SYNPO mRNAs were comparable to glomeruli, while synaptopodin and nephrin proteins and NPHS1 and NPHS2 mRNAs were <5% of glomerular levels. Expression of Wilms' tumor-1 (WT1) mRNA in mouse lines was comparable to glomeruli, but rat and human lines expressed little WT1. Undifferentiated human and mouse lines had similar proliferation rates that decreased after differentiation, while the rate in rat cells remained constant. The motility of different lines varied as measured by both general motility and wound-healing assays. The toxicity of puromycin aminonucleoside was MS ∼ JR >> KE, and of doxorubicin was JR ∼ KE > MS, while HK cells were almost unaffected. Process formation was largely a result of contractile action after formation of lamellipodia. These findings demonstrate dramatic differences in marker expression, response to toxins, and motility between lines of podocytes from different species and even between similarly-derived mouse lines. PMID:21632959
Chittiprol, Seetharamaiah; Chen, Phylip; Petrovic-Djergovic, Danica; Eichler, Tad; Ransom, Richard F
2011-09-01
The state-of-the-art cultured podocyte is conditionally immortalized by expression of a temperature-sensitive mutant of the SV40 large-T antigen. These cultures proliferate at 33°C and differentiate at 37°C into arborized cells that more closely resemble in vivo podocytes. However, the degree of resemblance remains controversial. In this study, several parameters were measured in podocyte cell lines derived from mouse (JR, KE), human (MS), and rat (HK). In all lines, the quantities of NEPH1 and podocin proteins and NEPH1 and SYNPO mRNAs were comparable to glomeruli, while synaptopodin and nephrin proteins and NPHS1 and NPHS2 mRNAs were <5% of glomerular levels. Expression of Wilms' tumor-1 (WT1) mRNA in mouse lines was comparable to glomeruli, but rat and human lines expressed little WT1. Undifferentiated human and mouse lines had similar proliferation rates that decreased after differentiation, while the rate in rat cells remained constant. The motility of different lines varied as measured by both general motility and wound-healing assays. The toxicity of puromycin aminonucleoside was MS ∼ JR > KE, and of doxorubicin was JR ∼ KE > MS, while HK cells were almost unaffected. Process formation was largely a result of contractile action after formation of lamellipodia. These findings demonstrate dramatic differences in marker expression, response to toxins, and motility between lines of podocytes from different species and even between similarly-derived mouse lines.
Vaccarino, Viola; Badimon, Lina; Corti, Roberto; de Wit, Cor; Dorobantu, Maria; Hall, Alistair; Koller, Akos; Marzilli, Mario; Pries, Axel; Bugiardini, Raffaele
2011-04-01
Cardiovascular disease (CVD) is the leading cause of death in women, and knowledge of the clinical consequences of atherosclerosis and CVD in women has grown tremendously over the past 20 years. Research efforts have increased and many reports on various aspects of ischaemic heart disease (IHD) in women have been published highlighting sex differences in pathophysiology, presentation, and treatment of IHD. Data, however, remain limited. A description of the state of the science, with recognition of the shortcomings of current data, is necessary to guide future research and move the field forward. In this report, we identify gaps in existing literature and make recommendations for future research. Women largely share similar cardiovascular risk factors for IHD with men; however, women with suspected or confirmed IHD have less coronary atherosclerosis than men, even though they are older and have more cardiovascular risk factors than men. Coronary endothelial dysfunction and microvascular disease have been proposed as important determinants in the aetiology and prognosis of IHD in women, but research is limited on whether sex differences in these mechanisms truly exist. Differences in the epidemiology of IHD between women and men remain largely unexplained, as we are still unable to explain why women are protected towards IHD until older age compared with men. Eventually, a better understanding of these processes and mechanisms may improve the prevention and the clinical management of IHD in women.
Assemblages of saproxylic beetles on large downed trunks of oak.
Milberg, Per; Bergman, Karl-Olof; Sancak, Kerem; Jansson, Nicklas
2016-03-01
Old living oaks (Quercus robur) are known as a very species-rich habitat for saproxylic beetles, but it is less clear to what extent such veteran trees differ from an even rarer feature: downed trunks of large oaks. In this study, we set out to sample this habitat, using window traps, with two aims: (1) to describe the variation of assemblages among downed trunks of different type and (2) to compare beetles on downed oaks with data from veteran standing trees. The results showed that trunk volume and sun exposure better explained assemblages as well as species numbers on downed trunks than did decay stage. Furthermore, species classified as facultative saproxylic species showed weak or no differentiation among downed trunks. Species with different feeding habits showed no apparent differentiation among downed trunks. Furthermore, species composition on dead, downed oak trunks differed sharply from that of living, veteran oaks. Wood or bark feeders were more common on veterans than downed trunks, but there was no difference for those species feeding on fungi or those feeding on insects and their remains. In conclusion, for a successful conservation of the saproxylic beetle fauna it is important to keep downed oak trunks, and particularly large ones, in forest and pastures as they constitute a saproxylic habitat that differs from that of living trees.
Compassion and contamination. Cultural differences in vegetarianism.
Ruby, Matthew B; Heine, Steven J; Kamble, Shanmukh; Cheng, Tessa K; Waddar, Mahadevi
2013-12-01
A growing body of research has shown that Western vegetarians report more concern for animal welfare and environmental sustainability, and endorse more liberal values than do Western omnivores. However, despite the prevalence of Indian vegetarianism, its psychological associations and underpinnings remain largely unexamined. In Study 1, we find that Euro-American vegetarians are more concerned than omnivores with the impact of their daily food choices on the environment and animal welfare, show more concern for general animal welfare, and endorse universalistic values more, yet among Indian participants, these differences are not significant. In Study 2, we show that Indian vegetarians more strongly endorse the belief that eating meat is polluting, and show a heightened concern for the conservative ethics of Purity, Authority, and Ingroup relative to their omnivorous peers, whereas these differences are largely absent among Euro-Canadians and Euro-Americans. Copyright © 2013 Elsevier Ltd. All rights reserved.
The genetic basis of parental care evolution in monogamous mice
Bendesky, Andres; Kwon, Young-Mi; Lassance, Jean-Marc; Lewarch, Caitlin L; Yao, Shenqin; Peterson, Brant K; He, Meng Xiao; Dulac, Catherine; Hoekstra, Hopi E
2017-01-01
Summary Parental care is essential for the survival of mammals, yet the mechanisms underlying its evolution remain largely unknown. Here we show that two sister species of mice, Peromyscus polionotus and P. maniculatus, have large and heritable differences in parental behaviour. Using quantitative genetics, we identify 12 genomic regions that affect parental care, eight of which have sex-specific effects, suggesting that parental care can evolve independently in males and females. Furthermore, some regions affect parental care broadly, whereas others affect specific behaviours, such as nest building. Of the genes linked to differences in nest-building behaviour, vasopressin is differentially expressed in the hypothalamus of the two species, with increased levels associated with less nest building. Using pharmacology in Peromyscus and chemogenetics in Mus, we show that vasopressin inhibits nest building but not other parental behaviours. Together, our results indicate that variation in an ancient neuropeptide contributes to interspecific differences in parental care. PMID:28424518
Minireview: Hormones and human sexual orientation.
Balthazart, Jacques
2011-08-01
Many people believe that sexual orientation (homosexuality vs. heterosexuality) is determined by education and social constraints. There are, however, a large number of studies indicating that prenatal factors have an important influence on this critical feature of human sexuality. Sexual orientation is a sexually differentiated trait (over 90% of men are attracted to women and vice versa). In animals and men, many sexually differentiated characteristics are organized during early life by sex steroids, and one can wonder whether the same mechanism also affects human sexual orientation. Two types of evidence support this notion. First, multiple sexually differentiated behavioral, physiological, or even morphological traits are significantly different in homosexual and heterosexual populations. Because some of these traits are known to be organized by prenatal steroids, including testosterone, these differences suggest that homosexual subjects were, on average, exposed to atypical endocrine conditions during development. Second, clinical conditions associated with significant endocrine changes during embryonic life often result in an increased incidence of homosexuality. It seems therefore that the prenatal endocrine environment has a significant influence on human sexual orientation but a large fraction of the variance in this behavioral characteristic remains unexplained to date. Genetic differences affecting behavior either in a direct manner or by changing embryonic hormone secretion or action may also be involved. How these biological prenatal factors interact with postnatal social factors to determine life-long sexual orientation remains to be determined.
Minireview: Hormones and Human Sexual Orientation
2011-01-01
Many people believe that sexual orientation (homosexuality vs. heterosexuality) is determined by education and social constraints. There are, however, a large number of studies indicating that prenatal factors have an important influence on this critical feature of human sexuality. Sexual orientation is a sexually differentiated trait (over 90% of men are attracted to women and vice versa). In animals and men, many sexually differentiated characteristics are organized during early life by sex steroids, and one can wonder whether the same mechanism also affects human sexual orientation. Two types of evidence support this notion. First, multiple sexually differentiated behavioral, physiological, or even morphological traits are significantly different in homosexual and heterosexual populations. Because some of these traits are known to be organized by prenatal steroids, including testosterone, these differences suggest that homosexual subjects were, on average, exposed to atypical endocrine conditions during development. Second, clinical conditions associated with significant endocrine changes during embryonic life often result in an increased incidence of homosexuality. It seems therefore that the prenatal endocrine environment has a significant influence on human sexual orientation but a large fraction of the variance in this behavioral characteristic remains unexplained to date. Genetic differences affecting behavior either in a direct manner or by changing embryonic hormone secretion or action may also be involved. How these biological prenatal factors interact with postnatal social factors to determine life-long sexual orientation remains to be determined. PMID:21693676
Brennan, Christine; Booth, James R.
2016-01-01
Linguistic knowledge, cognitive ability, and instruction influence how adults acquire a second orthography yet it remains unclear how different forms of instruction influence grain size sensitivity and subsequent decoding skill and speed. Thirty-seven monolingual, literate English-speaking adults were trained on a novel artificial orthography given initial instruction that directed attention to either large or small grain size units (i.e., words or letters). We examined how initial instruction influenced processing speed (i.e., reaction time (RT)) and sensitivity to different orthographic grain sizes (i.e., rimes and letters). Directing attention to large grain size units during initial instruction resulted in higher accuracy for rimes, whereas directing attention to smaller grain size units resulted in slower RTs across all measures. Additionally, phonological awareness skill modulated early learning effects, compensating for the limitations of the initial instruction provided. Collectively, these findings suggest that when adults are learning to read a second orthography, consideration should be given to how initial instruction directs attention to different grain sizes and inherent phonological awareness ability. PMID:27829705
ERIC Educational Resources Information Center
Key, Alexandra P.; Ibanez, Lisa V.; Henderson, Heather A.; Warren, Zachary; Messinger, Daniel S.; Stone, Wendy L.
2015-01-01
Few behavioral indices of risk for autism spectrum disorders (ASD) are present before 12 months, and potential biomarkers remain largely unexamined. This prospective study of infant siblings of children with ASD (n = 16) and low-risk comparison infants (n = 15) examined group differences in event-related potentials (ERPs) indexing processing of…
Attrition in a Large Scale Longitudinal Study of the Elderly: The Role of Health-Status Variables.
ERIC Educational Resources Information Center
Horgas, Ann L.; And Others
In a longitudinal study, subject attrition constitutes a potential threat to the usefulness of data collected from subjects remaining in later waves of the study. If attrition is selective, then the sample at later waves of the study may be representative of a different population than that represented at the outset of the study. This study…
ERIC Educational Resources Information Center
Litwin, James L.; Rentz, Audrey L.
An analysis of survey data collected at Bowling Green State University during the years 1973 to 1976 found that the objectives, attitudes, and background characteristics of successive classes of entering freshmen have remained very stable. While differences between men and women on certain traits are at times fairly large, the magnitude of the…
Immunotherapy targeting immune check-point(s) in brain metastases.
Di Giacomo, Anna Maria; Valente, Monica; Covre, Alessia; Danielli, Riccardo; Maio, Michele
2017-08-01
Immunotherapy with monoclonal antibodies (mAb) directed to different immune check-point(s) is showing a significant clinical impact in a growing number of human tumors of different histotype, both in terms of disease response and long-term survival patients. In this rapidly changing scenario, treatment of brain metastases remains an high unmeet medical need, and the efficacy of immunotherapy in these highly dismal clinical setting remains to be largely demonstrated. Nevertheless, up-coming observations are beginning to suggest a clinical potential of cancer immunotherapy also in brain metastases, regardless the underlying tumor histotype. These observations remain to be validated in larger clinical trials eventually designed also to address the efficacy of therapeutic mAb to immune check-point(s) within multimodality therapies for brain metastases. Noteworthy, the initial proofs of efficacy on immunotherapy in central nervous system metastases are already fostering clinical trials investigating its therapeutic potential also in primary brain tumors. We here review ongoing immunotherapeutic approaches to brain metastases and primary brain tumors, and the foreseeable strategies to overcome their main biologic hurdles and clinical challenges. Copyright © 2017 Elsevier Ltd. All rights reserved.
Nolan, Matthew J.; Harman, Kimberley; Boulton, Kay; Hume, David A.; Tomley, Fiona M.; Stabler, Richard A.; Blake, Damer P.
2017-01-01
Eimeria species cause the intestinal disease coccidiosis, most notably in poultry. While the direct impact of coccidiosis on animal health and welfare is clear, its influence on the enteric microbiota and by-stander effects on chicken health and production remains largely unknown, with the possible exception of Clostridium perfringens (necrotic enteritis). This study evaluated the composition and structure of the caecal microbiome in the presence or absence of a defined Eimeria tenella challenge infection in Cobb500 broiler chickens using 16S rRNA amplicon sequencing. The severity of clinical coccidiosis in individual chickens was quantified by caecal lesion scoring and microbial changes associated with different lesion scores identified. Following E. tenella infection the diversity of taxa within the caecal microbiome remained largely stable. However, infection induced significant changes in the abundance of some microbial taxa. The greatest changes were detected in birds displaying severe caecal pathology; taxa belonging to the order Enterobacteriaceae were increased, while taxa from Bacillales and Lactobacillales were decreased with the changes correlated with lesion severity. Significantly different profiles were also detected in infected birds which remained asymptomatic (lesion score 0), with taxa belonging to the genera Bacteroides decreased and Lactobacillus increased. Many differential taxa from the order Clostridiales were identified, with some increasing and others decreasing in abundance in Eimeria-infected animals. The results support the view that caecal microbiome dysbiosis associated with Eimeria infection contributes to disease pathology, and could be a target for intervention to mitigate the impact of coccidiosis on poultry productivity and welfare. This work highlights that E. tenella infection has a significant impact on the abundance of some caecal bacteria with notable differences detected between lesion score categories emphasising the importance of accounting for differences in caecal lesions when investigating the relationship between E. tenella and the poultry intestinal microbiome. PMID:28934262
How much a galaxy knows about its large-scale environment?: An information theoretic perspective
NASA Astrophysics Data System (ADS)
Pandey, Biswajit; Sarkar, Suman
2017-05-01
The small-scale environment characterized by the local density is known to play a crucial role in deciding the galaxy properties but the role of large-scale environment on galaxy formation and evolution still remain a less clear issue. We propose an information theoretic framework to investigate the influence of large-scale environment on galaxy properties and apply it to the data from the Galaxy Zoo project that provides the visual morphological classifications of ˜1 million galaxies from the Sloan Digital Sky Survey. We find a non-zero mutual information between morphology and environment that decreases with increasing length-scales but persists throughout the entire length-scales probed. We estimate the conditional mutual information and the interaction information between morphology and environment by conditioning the environment on different length-scales and find a synergic interaction between them that operates up to at least a length-scales of ˜30 h-1 Mpc. Our analysis indicates that these interactions largely arise due to the mutual information shared between the environments on different length-scales.
Reduced oxygen at high altitude limits maximum size.
Peck, L S; Chapelle, G
2003-01-01
The trend towards large size in marine animals with latitude, and the existence of giant marine species in polar regions have long been recognized, but remained enigmatic until a recent study showed it to be an effect of increased oxygen availability in sea water of a low temperature. The effect was apparent in data from 12 sites worldwide because of variations in water oxygen content controlled by differences in temperature and salinity. Another major physical factor affecting oxygen content in aquatic environments is reduced pressure at high altitude. Suitable data from high-altitude sites are very scarce. However, an exceptionally rich crustacean collection, which remains largely undescribed, was obtained by the British 1937 expedition from Lake Titicaca on the border between Peru and Bolivia in the Andes at an altitude of 3809 m. We show that in Lake Titicaca the maximum length of amphipods is 2-4 times smaller than other low-salinity sites (Caspian Sea and Lake Baikal). PMID:14667371
NASA Astrophysics Data System (ADS)
Lopatina, D. A.; Zanina, O. G.
2006-10-01
The comparative analysis of palynomorphs and plant megafossils (fruits, seeds, twigs, leaves) in the Upper Pleistocene host sediments and materials filling in fossil burrows of gophers, their coprolites included, at the Duvannyi Yar, Stanchikovskii Yar and Zelenyi Mys sites of the Kolyma Lowland is carried out. Genera Salix, Lychnis, Silene, Draba, Potentilla, Larix, and families Poaceae, Polygonaceae, Cyperaceae, Compositae, and Leguminosae are determined among palynological remains and megafossils. Factors responsible for qualitative and quantitative differences in taxonomic compositions of palynological and megafossil assemblages are biological peculiarities of plants, different character of fossilization of palynomorphs and large plant remains, geographic conditions, different genesis of assemblages (allochthonous for microfossils and autochthonous for megafossils), and inadequately known morphology of certain spore and pollen taxa. The comprehensive paleobotanical analysis leads to the conclusion that the study region was occupied in the Late Pleistocene by plant communities of humid to somewhat dryer tundra with separate areas of pioneering and steppe vegetation.
Jung, Eunice L.; Zadbood, Asieh; Lee, Sang-Hun; Tomarken, Andrew J.; Blake, Randolph
2013-01-01
We live in a cluttered, dynamic visual environment that poses a challenge for the visual system: for objects, including those that move about, to be perceived, information specifying those objects must be integrated over space and over time. Does a single, omnibus mechanism perform this grouping operation, or does grouping depend on separate processes specialized for different feature aspects of the object? To address this question, we tested a large group of healthy young adults on their abilities to perceive static fragmented figures embedded in noise and to perceive dynamic point-light biological motion figures embedded in dynamic noise. There were indeed substantial individual differences in performance on both tasks, but none of the statistical tests we applied to this data set uncovered a significant correlation between those performance measures. These results suggest that the two tasks, despite their superficial similarity, require different segmentation and grouping processes that are largely unrelated to one another. Whether those processes are embodied in distinct neural mechanisms remains an open question. PMID:24198799
Jung, Eunice L; Zadbood, Asieh; Lee, Sang-Hun; Tomarken, Andrew J; Blake, Randolph
2013-01-01
WE LIVE IN A CLUTTERED, DYNAMIC VISUAL ENVIRONMENT THAT POSES A CHALLENGE FOR THE VISUAL SYSTEM: for objects, including those that move about, to be perceived, information specifying those objects must be integrated over space and over time. Does a single, omnibus mechanism perform this grouping operation, or does grouping depend on separate processes specialized for different feature aspects of the object? To address this question, we tested a large group of healthy young adults on their abilities to perceive static fragmented figures embedded in noise and to perceive dynamic point-light biological motion figures embedded in dynamic noise. There were indeed substantial individual differences in performance on both tasks, but none of the statistical tests we applied to this data set uncovered a significant correlation between those performance measures. These results suggest that the two tasks, despite their superficial similarity, require different segmentation and grouping processes that are largely unrelated to one another. Whether those processes are embodied in distinct neural mechanisms remains an open question.
Astrophysics and Cosmology: International Partnerships
NASA Astrophysics Data System (ADS)
Blandford, Roger
2016-03-01
Most large projects in astrophysics and cosmology are international. This raises many challenges including: --Aligning the sequence of: proposal, planning, selection, funding, construction, deployment, operation, data mining in different countries --Managing to minimize cost growth through reconciling different practices --Communicating at all levels to ensure a successful outcome --Stabilizing long term career opportunities. There has been considerable progress in confronting these challenges. Lessons learned from past collaborations are influencing current facilities but much remains to be done if we are to optimize the scientific and public return on the expenditure of financial and human resources.
Assessing the effects of large mobile predators on ecosystem connectivity.
McCauley, Douglas J; Young, Hillary S; Dunbar, Robert B; Estes, James A; Semmens, Brice X; Micheli, Fiorenza
2012-09-01
Large predators are often highly mobile and can traverse and use multiple habitats. We know surprisingly little about how predator mobility determines important processes of ecosystem connectivity. Here we used a variety of data sources drawn from Palmyra Atoll, a remote tropical marine ecosystem where large predators remain in high abundance, to investigate how these animals foster connectivity. Our results indicate that three of Palmyra's most abundant large predators (e.g., two reef sharks and one snapper) use resources from different habitats creating important linkages across ecosystems. Observations of cross-system foraging such as this have important implications for the understanding of ecosystem functioning, the management of large-predator populations, and the design of conservation measures intended to protect whole ecosystems. In the face of widespread declines of large, mobile predators, it is important that resource managers, policy makers, and ecologists work to understand how these predators create connectivity and to determine the impact that their depletions may be having on the integrity of these linkages.
Nurture affects gender differences in spatial abilities.
Hoffman, Moshe; Gneezy, Uri; List, John A
2011-09-06
Women remain significantly underrepresented in the science, engineering, and technology workforce. Some have argued that spatial ability differences, which represent the most persistent gender differences in the cognitive literature, are partly responsible for this gap(.) The underlying forces at work shaping the observed spatial ability differences revolve naturally around the relative roles of nature and nurture. Although these forces remain among the most hotly debated in all of the sciences, the evidence for nurture is tenuous, because it is difficult to compare gender differences among biologically similar groups with distinct nurture. In this study, we use a large-scale incentivized experiment with nearly 1,300 participants to show that the gender gap in spatial abilities, measured by time to solve a puzzle, disappears when we move from a patrilineal society to an adjoining matrilineal society. We also show that about one-third of the effect can be explained by differences in education. Given that none of our participants have experience with puzzle solving and that villagers from both societies have the same means of subsistence and shared genetic background, we argue that these results show the role of nurture in the gender gap in cognitive abilities.
Nurture affects gender differences in spatial abilities
Hoffman, Moshe; Gneezy, Uri; List, John A.
2011-01-01
Women remain significantly underrepresented in the science, engineering, and technology workforce. Some have argued that spatial ability differences, which represent the most persistent gender differences in the cognitive literature, are partly responsible for this gap. The underlying forces at work shaping the observed spatial ability differences revolve naturally around the relative roles of nature and nurture. Although these forces remain among the most hotly debated in all of the sciences, the evidence for nurture is tenuous, because it is difficult to compare gender differences among biologically similar groups with distinct nurture. In this study, we use a large-scale incentivized experiment with nearly 1,300 participants to show that the gender gap in spatial abilities, measured by time to solve a puzzle, disappears when we move from a patrilineal society to an adjoining matrilineal society. We also show that about one-third of the effect can be explained by differences in education. Given that none of our participants have experience with puzzle solving and that villagers from both societies have the same means of subsistence and shared genetic background, we argue that these results show the role of nurture in the gender gap in cognitive abilities. PMID:21876159
García-Palacios, Pablo; Maestre, Fernando T; Kattge, Jens; Wall, Diana H
2013-08-01
Climate and litter quality have been identified as major drivers of litter decomposition at large spatial scales. However, the role played by soil fauna remains largely unknown, despite its importance for litter fragmentation and microbial activity. We synthesised litterbag studies to quantify the effect sizes of soil fauna on litter decomposition rates at the global and biome scales, and to assess how climate, litter quality and soil fauna interact to determine such rates. Soil fauna consistently enhanced litter decomposition at both global and biome scales (average increment ~ 37%). [corrected]. However, climate and litter quality differently modulated the effects of soil fauna on decomposition rates between biomes, from climate-driven biomes to those where climate effects were mediated by changes in litter quality. Our results advocate for the inclusion of biome-specific soil fauna effects on litter decomposition as a mean to reduce the unexplained variation in large-scale decomposition models. © 2013 John Wiley & Sons Ltd/CNRS.
Photometric Redshifts for the Large-Area Stripe 82X Multiwavelength Survey
NASA Astrophysics Data System (ADS)
Tasnim Ananna, Tonima; Salvato, Mara; Urry, C. Megan; LaMassa, Stephanie M.; STRIPE 82X
2016-06-01
The Stripe 82X survey currently includes 6000 X-ray sources in 31.3 square degrees of XMM-Newton and Chandra X-ray coverage, most of which are AGN. Using a maximum-likelihood approach, we identified optical and infrared counterparts in the SDSS, VHS K-band and WISE W1-band catalogs. 1200 objects which had different best associations in different catalogs were checked by eye. Our most recent paper provided the multiwavelength catalogs for this sample. More than 1000 counterparts have spectroscopic redshifts, either from SDSS spectroscopy or our own follow-up program. Using the extensive multiwavelength data in this field, we provide photometric redshift estimates for most of the remaining sources, which are 80-90% accurate according to the training set. Our sample has a large number of candidates that are very faint in optical and bright in IR. We expect a large fraction of these objects to be the obscured AGN sample we need to complete the census on black hole growth at a range of redshifts.
Paces, James B.; Wurster, Frederic C.
2014-01-01
Near-surface physical and chemical process can strongly affect dissolved-ion concentrations and stable isotope compositions of water in wetland settings, especially under arid climate conditions. In contrast, heavy radiogenic isotopes of strontium (87Sr/86Sr) and uranium (234U/238U) remain largely unaffected and can be used to help identify unique signatures from different sources and quantify end-member mixing that would otherwise be difficult to determine. The utility of combined Sr and U isotopes are demonstrated in this study of wetland habitats on the Pahranagat National Wildlife Refuge, which depend on supply from large-volume springs north of the Refuge, and from small-volume springs and seeps within the Refuge. Water budgets from these sources have not been quantified previously. Evaporation, transpiration, seasonally variable surface flow, and water management practices complicate the use of conventional methods for determining source contributions and mixing relations. In contrast, 87Sr/86Sr and 234U/238U remain unfractionated under these conditions, and compositions at a given site remain constant. Differences in Sr- and U-isotopic signatures between individual sites can be related by simple two- or three-component mixing models. Results indicate that surface flow constituting the Refuge’s irrigation source consists of a 65:25:10 mixture of water from two distinct regionally sourced carbonate aquifer springs, and groundwater from locally sourced volcanic aquifers. Within the Refuge, contributions from the irrigation source and local groundwater are readily determined and depend on proximity to those sources as well as water management practices.
NASA Astrophysics Data System (ADS)
Paces, James B.; Wurster, Frederic C.
2014-09-01
Near-surface physical and chemical process can strongly affect dissolved-ion concentrations and stable-isotope compositions of water in wetland settings, especially under arid climate conditions. In contrast, heavy radiogenic isotopes of strontium (87Sr/86Sr) and uranium (234U/238U) remain largely unaffected and can be used to help identify unique signatures from different sources and quantify end-member mixing that would otherwise be difficult to determine. The utility of combined Sr and U isotopes are demonstrated in this study of wetland habitats on the Pahranagat National Wildlife Refuge, which depend on supply from large-volume springs north of the Refuge, and from small-volume springs and seeps within the Refuge. Water budgets from these sources have not been quantified previously. Evaporation, transpiration, seasonally variable surface flow, and water management practices complicate the use of conventional methods for determining source contributions and mixing relations. In contrast, 87Sr/86Sr and 234U/238U remain unfractionated under these conditions, and compositions at a given site remain constant. Differences in Sr- and U-isotopic signatures between individual sites can be related by simple two- or three-component mixing models. Results indicate that surface flow constituting the Refuge's irrigation source consists of a 65:25:10 mixture of water from two distinct regionally sourced carbonate-aquifer springs, and groundwater from locally sourced volcanic aquifers. Within the Refuge, contributions from the irrigation source and local groundwater are readily determined and depend on proximity to those sources as well as water management practices.
Scopa Kelso, Rebecca
2018-06-01
Human subadult skeletal remains can provide a unique perspective into biosocial aspects of Mississippian period population interactions within and between the Middle Cumberland (MCR) and Eastern Tennessee Regions (ETR). The majority of previous studies have concentrated on adult skeletal remains, leaving out a large and extremely important population segment. Skeletal indicators of disease, growth, body proportions, and metabolic stress were collected from subadult remains from five archaeological sites over several temporal periods. Crucial to overcoming limitations associated with the osteological paradox, the biological results were placed into an archaeological context based on prior studies as well as paleoclimatological data. Results reveal homogeneity both within and between regions for most skeletal indicators. However, MCR individuals exhibit a higher frequency of pathology than those from ETC, while stature is significantly lower in younger subadults from the MCR. Within the ETR, there is no evidence for biological differences between Early Dallas and subsequent Late Dallas and Mouse Creek cultural phases. Despite presumed signs of increased conflict at the Dallas site, frequencies and types of skeletal pathology and growth disruptions are comparable to other regional sites. These findings suggest that despite cultural differences between the ETR and MCR, there was no large-scale intrusion from an outside population into the ETR during the Late Mississippian Period, or if one occurred, it is biologically invisible. Combined with climatic and archaeobotanical data, results suggest the MCR subadults were under increased stress in their earlier years. This may have been associated with increased interpersonal violence and dependence on few food sources occurring with greater scarcity. © 2018 Wiley Periodicals, Inc.
Whales Use Distinct Strategies to Counteract Solar Ultraviolet Radiation
Martinez-Levasseur, Laura M.; Birch-Machin, Mark A.; Bowman, Amy; Gendron, Diane; Weatherhead, Elizabeth; Knell, Robert J.; Acevedo-Whitehouse, Karina
2013-01-01
A current threat to the marine ecosystem is the high level of solar ultraviolet radiation (UV). Large whales have recently been shown to suffer sun-induced skin damage from continuous UV exposure. Genotoxic consequences of such exposure remain unknown for these long-lived marine species, as does their capacity to counteract UV-induced insults. We show that UV exposure induces mitochondrial DNA damage in the skin of seasonally sympatric fin, sperm, and blue whales and that this damage accumulates with age. However, counteractive molecular mechanisms are markedly different between species. For example, sperm whales, a species that remains for long periods at the sea surface, activate genotoxic stress pathways in response to UV exposure whereas the paler blue whale relies on increased pigmentation as the season progresses. Our study also shows that whales can modulate their responses to fluctuating levels of UV, and that different evolutionary constraints may have shaped their response strategies. PMID:23989080
Complex Homology and the Evolution of Nervous Systems
Liebeskind, Benjamin J.; Hillis, David M.; Zakon, Harold H.; Hofmann, Hans A.
2016-01-01
We examine the complex evolution of animal nervous systems and discuss the ramifications of this complexity for inferring the nature of early animals. Although reconstructing the origins of nervous systems remains a central challenge in biology, and the phenotypic complexity of early animals remains controversial, a compelling picture is emerging. We now know that the nervous system and other key animal innovations contain a large degree of homoplasy, at least on the molecular level. Conflicting hypotheses about early nervous system evolution are due primarily to differences in the interpretation of this homoplasy. We highlight the need for explicit discussion of assumptions and discuss the limitations of current approaches for inferring ancient phenotypic states. PMID:26746806
NASA Astrophysics Data System (ADS)
Belle, Simon; Freiberg, Rene; Poska, Anneli; Agasild, Helen; Alliksaar, Tiiu; Tõnno, Ilmar
2018-05-01
The study of lake sediments and archived biological remains is a promising approach to better understand the impacts of climate change on aquatic ecosystems. Small lakes have been shown to be strongly sensitive to past climate change, but similar information is lacking for large lakes. By identifying responses to climate change of carbon flows through benthic food web in two different sized lakes, we aimed to understand how lake morphometry can mediate the effects of climate change. We reconstructed the dynamics of phytoplankton community composition and carbon resources sustaining chironomid biomass during the Holocene from the combined analysis of sedimentary pigment quantification and carbon stable isotopic composition of subfossil chironomid head capsules (δ13CHC) in a large lake in the Baltic area (Estonia). Our results showed that chironomid biomass in the large lake was mainly sustained by phytoplankton, with no significant relationship between δ13CHC values and temperature fluctuations. We suggest that lake morphometry (including distance of the sampling zone to the shoreline, and lake volume for primary producers) mediates the effects of climate change, making large lakes less sensitive to climate change. Complementary studies are needed to better understand differences in organic matter dynamics in different sized lakes and to characterize the response of the aquatic carbon cycle to past climate change.
NASA Astrophysics Data System (ADS)
van Geel, Bas; Fisher, Daniel C.; Rountrey, Adam N.; van Arkel, Jan; Duivenvoorden, Joost F.; Nieman, Aline M.; van Reenen, Guido B. A.; Tikhonov, Alexei N.; Buigues, Bernard; Gravendeel, Barbara
2011-12-01
Intestinal samples from the one-month-old Siberian mammoth calf 'Lyuba' were studied using light microscopy and ancient DNA to reconstruct its palaeo-environment and diet. The palynological record indicates a 'mammoth steppe'. At least some pollen of arboreal taxa was reworked, and thus the presence of trees on the landscape is uncertain. In addition to visual comparison of 11 microfossil spectra, a PCA analysis contributed to diet reconstruction. This yielded two clusters: one of samples from the small intestine and the other of large-intestine samples, indicating compositional differences in food remains along the intestinal tract, possibly reflecting different episodes of ingestion. Based on observed morphological damage we conclude that the cyperaceous plant remains and some remains of dwarf willows were originally eaten by a mature mammoth, most likely Lyuba's mother. The mammoth calf probably unintentionally swallowed well-preserved mosses and mineral particles while eating fecal material deposited on a soil surface covered with mosses. Coprophagy may have been a common habit for mammoths, and we therefore propose that fecal material should not be used to infer season of death of mammoths. DNA sequences of trnL and rbcL genes amplified from ancient DNA extracted from intestinal samples confirmed and supplemented plant identifications based on microfossils and macro-remains. Results from different extraction methods and barcoding markers complemented each other and show the value of longer protocols in addition to fast and commercially available extraction kits.
The new science of cognitive sex differences.
Miller, David I; Halpern, Diane F
2014-01-01
Surprising new findings indicate that many conclusions about sex differences and similarities in cognitive abilities need to be reexamined. Cognitive sex differences are changing, decreasing for some tasks whereas remaining stable or increasing for other tasks. Some sex differences are detected in infancy, but the data are complex and depend on task characteristics. Diverse disciplines have revolutionized our understanding of why these differences exist. For instance, fraternal-twin studies align with earlier literature to help establish the role of prenatal androgens and large international datasets help explain how cultural factors such as economic prosperity and gender equity affect females and males differently. Understanding how biological and environmental factors interact could help maximize cognitive potential and address pressing societal issues. Copyright © 2013 Elsevier Ltd. All rights reserved.
Intra-specific downsizing of frugivores affects seed germination of fleshy-fruited plant species
NASA Astrophysics Data System (ADS)
Pérez-Méndez, Néstor; Rodríguez, Airam; Nogales, Manuel
2018-01-01
The loss of largest-bodied individuals within species of frugivorous animals is one of the major consequences of defaunation. The gradual disappearance of large-bodied frugivores is expected to entail a parallel deterioration in seed dispersal functionality if the remaining smaller-sized individuals are not so effective as seed dispersers. While the multiple impacts of the extinction of large bodied species have been relatively well studied, the impact of intraspecific downsizing (i.e. the extinction of large individuals within species) on seed dispersal has rarely been evaluated. Here we experimentally assessed the impact of body-size reduction in the frugivorous lizard Gallotia galloti (Lacertidae), an endemic species of the Canary Islands, on the seed germination patterns of two fleshy-fruited plant species (Rubia fruticosa and Withania aristata). Seed germination curves and the proportions of germinated seeds were compared for both plant species after being defecated by large-sized individuals and small-sized individuals. The data show that seeds of W. aristata defecated by larger-sized lizards germinated faster and in a higher percentage than those defecated by small-sized lizards, while no differences were found for R. fruticosa seeds. Our results suggest that disappearance of the largest individuals of frugivorous species may impair recruitment of some plant species by worsening seed germination. They also warn us of a potential cryptic loss of seed dispersal functionality on defaunated ecosystems, even when frugivorous species remain abundant.
Gender differences in patenting in the academic life sciences.
Ding, Waverly W; Murray, Fiona; Stuart, Toby E
2006-08-04
We analyzed longitudinal data on academic careers and conducted interviews with faculty members to determine the scope and causes of the gender gap in patenting among life scientists. Our regressions on a random sample of 4227 life scientists over a 30-year period show that women faculty members patent at about 40% of the rate of men. We found that the gender gap has improved over time but remains large.
Fluid valve with wide temperature range
NASA Technical Reports Server (NTRS)
Kast, Howard Berdolt (Inventor)
1976-01-01
A fluid valve suitable for either metering or pressure regulating fluids at various temperatures is provided for a fuel system as may be utilized in an aircraft gas turbine engine. The valve includes a ceramic or carbon pad which cooperates with a window in a valve plate to provide a variable area orifice which remains operational during large and sometimes rapid variations in temperature incurred from the use of different fuels.
Calos, J. B.; Sakaluk, S. K.
1998-01-01
The spermatophore transferred by male decorated crickets (Gryllodes sigillatus) includes a large gelatinous mass, the spermatophylax, that is consumed by the female after mating. This nuptial gift preoccupies the female while sperm are discharged from the remaining portion of the spermatophore, the sperm ampulla, into her reproductive tract. There is considerable variation in the mass of the spermatophylax, and about half of all males produce spermatophylaxes that are too small to ensure complete sperm transfer. We tested two hypotheses concerning the maintenance of this variation: (i) males trade-off investment in spermatophylaxes against copulation frequency; and (ii) males synthesize the largest spermatophylaxes of which they are physiologically capable. Males synthesizing large and small food gifts were permitted multiple mating opportunities with the same females, and allozyme markers were used to establish the paternity of offspring. There was a significant advantage to those males that mated first irrespective of gift size. This advantage probably arose, in part, because the sperm of first males would have had exclusive access to females' eggs during the first 24 hours of oviposition, and underscores the benefits of matings with virgin females. The paternity of 'small-gift' males increased with gift mass, but there was no such increase in 'large-gift' males. This difference probably stems from the relationship between gift mass and sperm transfer: most of the gifts of the large-gift males would have been above the threshold needed to achieve complete inseminations, whereas those of small-gift males would have been below the threshold. Within mating-order positions, there was no significant difference in the paternity of large-gift and small-gift males, a result seemingly consistent with the 'trade-off' hypothesis. However, there was no correlation between spermatophylax mass and male mating frequency, so that the mechanism by which small-gift males offset their fertilization disadvantage remains unknown.
Detecting Trends in Tropical Rainfall Characteristics, 1979-2003
NASA Technical Reports Server (NTRS)
Lau, K. M.; Wu, H. T.
2006-01-01
From analyses of blended space-based and ground-based global rainfall data, we found increasing trends in the occurrence of extreme heavy and light rain events, coupled to a decreasing trend in moderate rain events in the tropics during 1979-2003. The trends are consistent with a shift in the large-scale circulation associated with a) a relatively uniform increase in warm rain over the tropical oceans, b) enhanced ice-phase rain over the near-equatorial oceans, and c) reduced mixed-phase rain over the tropical ocean and land regions. Due to the large compensation among different rain categories, the total tropical rainfall trend remained undetectable.
Scaling laws of passive-scalar diffusion in the interstellar medium
NASA Astrophysics Data System (ADS)
Colbrook, Matthew J.; Ma, Xiangcheng; Hopkins, Philip F.; Squire, Jonathan
2017-05-01
Passive-scalar mixing (metals, molecules, etc.) in the turbulent interstellar medium (ISM) is critical for abundance patterns of stars and clusters, galaxy and star formation, and cooling from the circumgalactic medium. However, the fundamental scaling laws remain poorly understood in the highly supersonic, magnetized, shearing regime relevant for the ISM. We therefore study the full scaling laws governing passive-scalar transport in idealized simulations of supersonic turbulence. Using simple phenomenological arguments for the variation of diffusivity with scale based on Richardson diffusion, we propose a simple fractional diffusion equation to describe the turbulent advection of an initial passive scalar distribution. These predictions agree well with the measurements from simulations, and vary with turbulent Mach number in the expected manner, remaining valid even in the presence of a large-scale shear flow (e.g. rotation in a galactic disc). The evolution of the scalar distribution is not the same as obtained using simple, constant 'effective diffusivity' as in Smagorinsky models, because the scale dependence of turbulent transport means an initially Gaussian distribution quickly develops highly non-Gaussian tails. We also emphasize that these are mean scalings that apply only to ensemble behaviours (assuming many different, random scalar injection sites): individual Lagrangian 'patches' remain coherent (poorly mixed) and simply advect for a large number of turbulent flow-crossing times.
{13C }/{12C } ratios of pleistocene mummified remains from beringia
NASA Astrophysics Data System (ADS)
Bombin, Miguel; Muehlenbachs, Karlis
1985-01-01
During the Quaternary glacial episodes, when sea level was considerably lower, Asia and North America were linked by large extensions of circumarctic land (Beringia), which remained unglaciated. This land mass served not only as a biogeographical bridge for plants, animals, and humans, but also supported a biome very different from present tundra or boreal coniferous forests, which was dominated by steppes and a rich mammalian megafauna. Carbon stable isotope ratios of Beringian late Pleistocene mummified remains of bison, equids, mammoth, caribou, musk-ox, moose, woolly rhino, and other undetermined species, found preserved in permafrost, indicate that these megaherbivores fed exclusively on C 3 plants, and that C 4 grasses were not differentially ingested by bison, as previously suggested. Paleoclimatic constraints probably prevented the formation of a warm-season (C 4) guild during the later part of the growing season in the steppes of Beringia during the last glaciation.
The Role of Policy and Institutions on Health Spending.
de la Maisonneuve, Christine; Moreno-Serra, Rodrigo; Murtin, Fabrice; Oliveira Martins, Joaquim
2017-07-01
This paper investigates the impact of policies and institutions on health expenditures for a large panel of Organisation for Economic Co-operation and Development countries for the period of 2000-2010. A set of 20 policy and institutional indicators developed by the Organisation for Economic Co-operation and Development are integrated into a theoretically motivated econometric framework, alongside control variables related to demographic (dependency ratio) and non-demographic (income, prices and technology) drivers of health expenditures per capita. Although a large share of cross-country differences in public health expenditures can be explained by demographic and economic factors (around 71%), cross-country variations in policies and institutions also have a significant influence, explaining most of the remaining difference in public health spending (23%). Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.
Flexible Redistribution in Cognitive Networks.
Hartwigsen, Gesa
2018-06-15
Previous work has emphasized that cognitive functions in the human brain are organized into large-scale networks. However, the mechanisms that allow these networks to compensate for focal disruptions remain elusive. I suggest a new perspective on the compensatory flexibility of cognitive networks. First, I demonstrate that cognitive networks can rapidly change the functional weight of the relative contribution of different regions. Second, I argue that there is an asymmetry in the compensatory potential of different kinds of networks. Specifically, recruitment of domain-general functions can partially compensate for focal disruptions of specialized cognitive functions, but not vice versa. Considering the compensatory potential within and across networks will increase our understanding of functional adaptation and reorganization after brain lesions and offers a new perspective on large-scale neural network (re-)organization. Copyright © 2018 Elsevier Ltd. All rights reserved.
Domoic acid excretion in dungeness crabs, razor clams and mussels.
Schultz, Irvin R; Skillman, Ann; Woodruff, Dana
2008-07-01
Domoic acid (DA) is a neurotoxic amino acid produced by several marine algal species of the Pseudo-nitzschia (PN) genus. We studied the elimination of DA from hemolymph after intravascular (IV) injection in razor clams (Siliqua patula), mussels (Mytilus edulis) and Dungeness crabs (Cancer magister). Crabs were also injected with two other organic acids, dichloroacetic acid (DCAA) and kainic acid (KA). For IV dosing, hemolymph was repetitively sampled and DA concentrations measured by HPLC-UV. Toxicokinetic analysis of DA in crabs suggested most of the injected dose remained within hemolymph compartment with little extravascular distribution. This observation is in sharp contrast to results obtained from clams and mussels which exhibited similarly large apparent volumes of distribution despite large differences in overall clearance. These findings suggest fundamentally different storage and elimination processes are occurring for DA between bivalves and crabs.
Molina, Teresa
2016-04-01
I use anchoring vignettes from Indonesia, the United States, England, and China to study the extent to which differences in self-reported health across gender and education levels can be explained by the use of different response thresholds. To determine whether statistically significant differences between groups remain after adjusting thresholds, I calculate standard errors for the simulated probabilities, largely ignored in previous literature. Accounting for reporting heterogeneity reduces the gender gap in many health domains across the four countries, but to varying degrees. Health disparities across education levels persist and even widen after equalizing thresholds across the two groups.
Principles of Statistics: What the Sports Medicine Professional Needs to Know.
Riemann, Bryan L; Lininger, Monica R
2018-07-01
Understanding the results and statistics reported in original research remains a large challenge for many sports medicine practitioners and, in turn, may be among one of the biggest barriers to integrating research into sports medicine practice. The purpose of this article is to provide minimal essentials a sports medicine practitioner needs to know about interpreting statistics and research results to facilitate the incorporation of the latest evidence into practice. Topics covered include the difference between statistical significance and clinical meaningfulness; effect sizes and confidence intervals; reliability statistics, including the minimal detectable difference and minimal important difference; and statistical power. Copyright © 2018 Elsevier Inc. All rights reserved.
Replica Exchange with Solute Tempering: Efficiency in Large Scale Systems
Huang, Xuhui; Hagen, Morten; Kim, Byungchan; Friesner, Richard A.; Zhou, Ruhong; Berne, B. J.
2009-01-01
We apply the recently developed replica exchange with solute tempering (REST) to three large solvated peptide systems: an α-helix, a β-hairpin, and a TrpCage, with these peptides defined as the “central group”. We find that our original implementation of REST is not always more efficient than the replica exchange method (REM). Specifically, we find that exchanges between folded (F) and unfolded (U) conformations with vastly different structural energies are greatly reduced by the nonappearance of the water self-interaction energy in the replica exchange acceptance probabilities. REST, however, is expected to remain useful for a large class of systems for which the energy gap between the two states is not large, such as weakly bound protein–ligand complexes. Alternatively, a shell of water molecules can be incorporated into the central group, as discussed in the original paper. PMID:17439169
An interim report on the MCAT Essay Pilot Project.
Koenig, J A; Mitchell, K J
1988-01-01
Results from four pilot administrations of the Medical College Admission Test essay question are reported. Analyses focused on (a) the performance characteristics of sample groups differentiated by gender, size of hometown, race/ethnicity, and dominant language; (b) the relationships between essay scores and academic/demographic characteristics; and (c) the reliability of one 45-minute versus two 30-minute essays. No differences were found for examinees grouped by gender and size of home community. Mean differences among the racial/ethnic groups were explained largely by reading level differences. Differences in essay performance by language group were large and unexplained by reading level differences. No relationship was found between the essay score and the academic/demographic characteristics. Reliability estimates for two 30-minute essays were higher than for one 45-minute essay; however, the 30-minute period yielded writing of poorer quality. Test-retest reliabilities for the 45-minute topics will remain the focus of future studies as will performance by examinees for whom English is a second language. The impact of the essay on the selection process will also be assessed.
Changes in size of deforested patches in the Brazilian Amazon.
Rosa, Isabel M D; Souza, Carlos; Ewers, Robert M
2012-10-01
Different deforestation agents, such as small farmers and large agricultural businesses, create different spatial patterns of deforestation. We analyzed the proportion of deforestation associated with different-sized clearings in the Brazilian Amazon from 2002 through 2009. We used annual deforestation maps to determine total area deforested and the size distribution of deforested patches per year. The size distribution of deforested areas changed over time in a consistent, directional manner. Large clearings (>1000 ha) comprised progressively smaller amounts of total annual deforestation. The number of smaller clearings (6.25-50.00 ha) remained unchanged over time. Small clearings accounted for 73% of all deforestation in 2009, up from 30% in 2002, whereas the proportion of deforestation attributable to large clearings decreased from 13% to 3% between 2002 and 2009. Large clearings were concentrated in Mato Grosso, but also occurred in eastern Pará and in Rondônia. In 2002 large clearings accounted for 17%, 15%, and 10% of all deforestation in Mato Grosso, Pará, and Rondônia, respectively. Even in these states, where there is a highly developed agricultural business dominated by soybean production and cattle ranching, the proportional contribution of large clearings to total deforestation declined. By 2009 large clearings accounted for 2.5%, 3.5%, and 1% of all deforestation in Mato Grosso, Pará, and Rondônia, respectively. These changes in deforestation patch size are coincident with the implementation of new conservation policies by the Brazilian government, which suggests that these policies are not effectively reducing the number of small clearings in primary forest, whether these are caused by large landholders or smallholders, but have been more effective at reducing the frequency of larger clearings. ©2012 Society for Conservation Biology.
NASA Astrophysics Data System (ADS)
Weber, R. J.; Guo, H.; Russell, A. G.; Nenes, A.
2015-12-01
pH is a critical aerosol property that impacts many atmospheric processes, including biogenic secondary organic aerosol formation, gas-particle phase partitioning, and mineral dust or redox metal mobilization. Particle pH has also been linked to adverse health effects. Using a comprehensive data set from the Southern Oxidant and Aerosol Study (SOAS) as the basis for thermodynamic modeling, we have shown that particles are currently highly acidic in the southeastern US, with pH between 0 and 2. Sulfate and ammonium are the main acid-base components that determine particle pH in this region, however they have different sources and their concentrations are changing. Over 15 years of network data show that sulfur dioxide emission reductions have resulted in a roughly 70 percent decrease in sulfate, whereas ammonia emissions, mainly link to agricultural activities, have been largely steady, as have gas phase ammonia concentrations. This has led to the view that particles are becoming more neutralized. However, sensitivity analysis, based on thermodynamic modeling, to changing sulfate concentrations indicates that particles have remained highly acidic over the past decade, despite the large reductions in sulfate. Furthermore, anticipated continued reductions of sulfate and relatively constant ammonia emissions into the future will not significantly change particle pH until sulfate drops to clean continental background levels. The result reshapes our expectation of future particle pH and implies that atmospheric processes and adverse health effects linked to particle acidity will remain unchanged for some time into the future.
ERIC Educational Resources Information Center
Harris, Alma; Jones, Michelle
2017-01-01
The challenges of securing educational change and transformation, at scale, remain considerable. While sustained progress has been made in some education systems (Fullan, 2009; Hargreaves & Shirley, 2009) generally, it remains the case that the pathway to large-scale, system improvement is far from easy or straightforward. While large-scale…
Sensitivity analysis of key components in large-scale hydroeconomic models
NASA Astrophysics Data System (ADS)
Medellin-Azuara, J.; Connell, C. R.; Lund, J. R.; Howitt, R. E.
2008-12-01
This paper explores the likely impact of different estimation methods in key components of hydro-economic models such as hydrology and economic costs or benefits, using the CALVIN hydro-economic optimization for water supply in California. In perform our analysis using two climate scenarios: historical and warm-dry. The components compared were perturbed hydrology using six versus eighteen basins, highly-elastic urban water demands, and different valuation of agricultural water scarcity. Results indicate that large scale hydroeconomic hydro-economic models are often rather robust to a variety of estimation methods of ancillary models and components. Increasing the level of detail in the hydrologic representation of this system might not greatly affect overall estimates of climate and its effects and adaptations for California's water supply. More price responsive urban water demands will have a limited role in allocating water optimally among competing uses. Different estimation methods for the economic value of water and scarcity in agriculture may influence economically optimal water allocation; however land conversion patterns may have a stronger influence in this allocation. Overall optimization results of large-scale hydro-economic models remain useful for a wide range of assumptions in eliciting promising water management alternatives.
Structural connectivity of the developing human amygdala.
Saygin, Zeynep M; Osher, David E; Koldewyn, Kami; Martin, Rebecca E; Finn, Amy; Saxe, Rebecca; Gabrieli, John D E; Sheridan, Margaret
2015-01-01
A large corpus of research suggests that there are changes in the manner and degree to which the amygdala supports cognitive and emotional function across development. One possible basis for these developmental differences could be the maturation of amygdalar connections with the rest of the brain. Recent functional connectivity studies support this conclusion, but the structural connectivity of the developing amygdala and its different nuclei remains largely unstudied. We examined age related changes in the DWI connectivity fingerprints of the amygdala to the rest of the brain in 166 individuals of ages 5-30. We also developed a model to predict age based on individual-subject amygdala connectivity, and identified the connections that were most predictive of age. Finally, we segmented the amygdala into its four main nucleus groups, and examined the developmental changes in connectivity for each nucleus. We observed that with age, amygdalar connectivity becomes increasingly sparse and localized. Age related changes were largely localized to the subregions of the amygdala that are implicated in social inference and contextual memory (the basal and lateral nuclei). The central nucleus' connectivity also showed differences with age but these differences affected fewer target regions than the basal and lateral nuclei. The medial nucleus did not exhibit any age related changes. These findings demonstrate increasing specificity in the connectivity patterns of amygdalar nuclei across age.
Timbie, Justin W; Bogart, Andy; Damberg, Cheryl L; Elliott, Marc N; Haas, Ann; Gaillot, Sarah J; Goldstein, Elizabeth H; Paddock, Susan M
2017-12-01
To compare performance between Medicare Advantage (MA) and Fee-for-Service (FFS) Medicare during a time of policy changes affecting both programs. Performance data for 16 clinical quality measures and 6 patient experience measures for 9.9 million beneficiaries living in California, New York, and Florida. We compared MA and FFS performance overall, by plan type, and within service areas associated with contracts between CMS and MA organizations. Case mix-adjusted analyses (for measures not typically adjusted) were used to explore the effect of case mix on MA/FFS differences. Performance measures were submitted by MA organizations, obtained from the nationwide fielding of the Medicare Consumer Assessment of Healthcare Providers and Systems (MCAHPS) Survey, or derived from claims. Overall, MA outperformed FFS on all 16 clinical quality measures. Differences were large for HEDIS measures and small for Part D measures and remained after case mix adjustment. MA enrollees reported better experiences overall, but FFS beneficiaries reported better access to care. Relative to FFS, performance gaps were much wider for HMOs than PPOs. Excluding HEDIS measures, MA/FFS differences were much smaller in contract-level comparisons. Medicare Advantage/Fee-for-Service differences are often large but vary in important ways across types of measures and contracts. © Health Research and Educational Trust.
ERIC Educational Resources Information Center
Salisbury, Mark H.; Paulsen, Michael B.; Pascarella, Ernest T.
2011-01-01
Despite substantial efforts across postsecondary education to increase minority participation in study abroad, the homogeneity of study abroad participants remains largely unchanged (Dessoff in Int Educ 15(2):20-27, 2006; Shih in http://diverseeducation.com/article/13193/study-abroad-participation-up-except-among-minority-students.html, 2009).…
A bound particle coupled to two thermostats
NASA Astrophysics Data System (ADS)
Fogedby, Hans C.; Imparato, Alberto
2011-05-01
We consider a harmonically bound Brownian particle coupled to two distinct heat reservoirs at different temperatures. We show that the presence of a harmonic trap does not change the large deviation function from the case of a free Brownian particle discussed by Derrida and Brunet and Visco. Likewise, the Gallavotti-Cohen fluctuation theorem related to the entropy production at the heat sources remains in force. We support the analytical results with numerical simulations.
ERIC Educational Resources Information Center
Hollabaugh, Jaliene R.
2012-01-01
The purpose of my study was to explore the perceptions and experiences of inductive teachers in secondary education. My purposive sample included 11 licensed, inductive teachers from 10 different schools spanning eight school districts within a large metropolitan area of the Pacific Northwest. I used personal interviews, within a microethnographic…
NASA Astrophysics Data System (ADS)
Yilbas, B. S.; Akhtar, S. S.; Karatas, C.
2017-11-01
A Kevlar laminate has negative thermal expansion coefficient, which makes it difficult to machine at room temperaures using the conventional cutting tools. Contararily, laser machining of a Kevlar laminate provides advantages over the conventional methods because of the non-mechanical contact between the cutting tool and the workpiece. In the present study, laser circular cutting of Kevlar laminate is considered. The experiment is carried out to examine and evaluate the cutting sections. Temperature and stress fields formed in the cutting section are simulated in line with the experimental study. The influence of hole diameters on temperature and stress fields are investigated incorporating two different hole diameters. It is found that the Kevlar laminate cutting section is free from large size asperities such as large scale sideways burnings and attachemnt of charred residues. The maximum temperature along the cutting circumference remains higher for the large diameter hole than that of the small diameter hole. Temperature decay is sharp around the cutting section in the region where the cutting terminates. This, in turn, results in high temperature gradients and the thermal strain in the cutting region. von Mises stress remains high in the region where temperature gradients are high. von Mises stress follows similar to the trend of temperature decay around the cutting edges.
Chipperfield, J G; Havens, B
2001-05-01
This study examined life satisfaction among individuals who had undergone a transition in marital status and those whose marital status remained stable over a 7-year period. In particular, using data from a large-scale, longitudinal study we assessed life satisfaction as measured in 1983 and 1990 among 2,180 men and women between the ages of 67 and 102. Groups of individuals were identified on the basis of whether a spouse was present or absent at the two measurement points. This allowed for a classification of groups who experienced stability or transitions in marital status. Among those individuals whose marital status remained stable over the 7 years, women's life satisfaction declined and men's remained constant. Among those who experienced a transition--in particular, the loss of a spouse--a decline in life satisfaction was found for both men and women, decline being more predominant for men. In addition, men's life satisfaction increased over the 7-year period if they gained a spouse, whereas the same was not true for women. Generally, these findings imply that the relationship between marital status transitions or stability differs for men and women.
Dixon, Melissa W; Proffitt, Dennis R
2002-01-01
One important aspect of the pictorial representation of a scene is the depiction of object proportions. Yang, Dixon, and Proffitt (1999 Perception 28 445-467) recently reported that the magnitude of the vertical-horizontal illusion was greater for vertical extents presented in three-dimensional (3-D) environments compared to two-dimensional (2-D) displays. However, because all of the 3-D environments were large and all of the 2-D displays were small, the question remains whether the observed magnitude differences were due solely to the dimensionality of the displays (2-D versus 3-D) or to the perceived distal size of the extents (small versus large). We investigated this question by comparing observers' judgments of vertical relative to horizontal extents on a large but 2-D display compared to the large 3-D and the small 2-D displays used by Yang et al (1999). The results confirmed that the magnitude differences for vertical overestimation between display media are influenced more by the perceived distal object size rather than by the dimensionality of the display.
NASA Technical Reports Server (NTRS)
Dixon, Melissa W.; Proffitt, Dennis R.; Kaiser, M. K. (Principal Investigator)
2002-01-01
One important aspect of the pictorial representation of a scene is the depiction of object proportions. Yang, Dixon, and Proffitt (1999 Perception 28 445-467) recently reported that the magnitude of the vertical-horizontal illusion was greater for vertical extents presented in three-dimensional (3-D) environments compared to two-dimensional (2-D) displays. However, because all of the 3-D environments were large and all of the 2-D displays were small, the question remains whether the observed magnitude differences were due solely to the dimensionality of the displays (2-D versus 3-D) or to the perceived distal size of the extents (small versus large). We investigated this question by comparing observers' judgments of vertical relative to horizontal extents on a large but 2-D display compared to the large 3-D and the small 2-D displays used by Yang et al (1999). The results confirmed that the magnitude differences for vertical overestimation between display media are influenced more by the perceived distal object size rather than by the dimensionality of the display.
Large Earthquakes Disrupt Groundwater System by Breaching Aquitards
NASA Astrophysics Data System (ADS)
Wang, C. Y.; Manga, M.; Liao, X.; Wang, L. P.
2016-12-01
Changes of groundwater system by large earthquakes are widely recognized. Some changes have been attributed to increases in the vertical permeability but basic questions remain: How do increases in the vertical permeability occur? How frequent do they occur? How fast does the vertical permeability recover after the earthquake? Is there a quantitative measure for detecting the occurrence of aquitard breaching? Here we attempt to answer these questions by examining data accumulated in the past 15 years. Analyses of increased stream discharges and their geochemistry after large earthquakes show evidence that the excess water originates from groundwater released from high elevations by large increase of the vertical permeability. Water-level data from a dense network of clustered wells in a sedimentary basin near the epicenter of the 1999 M7.6 Chi-Chi earthquake in western Taiwan show that, while most confined aquifers remained confined after the earthquake, about 10% of the clustered wells show evidence of coseismic breaching of aquitards and a great increase of the vertical permeability. Water level in wells without evidence of coseismic breaching of aquitards show similar tidal response before and after the earthquake; wells with evidence of coseismic breaching of aquitards, on the other hand, show distinctly different tidal response before and after the earthquake and that the aquifers became hydraulically connected for many months thereafter. Breaching of aquitards by large earthquakes has significant implications for a number of societal issues such as the safety of water resources, the security of underground waste repositories, and the production of oil and gas. The method demonstrated here may be used for detecting the occurrence of aquitard breaching by large earthquakes in other seismically active areas.
Reverse Engineering Cellular Networks with Information Theoretic Methods
Villaverde, Alejandro F.; Ross, John; Banga, Julio R.
2013-01-01
Building mathematical models of cellular networks lies at the core of systems biology. It involves, among other tasks, the reconstruction of the structure of interactions between molecular components, which is known as network inference or reverse engineering. Information theory can help in the goal of extracting as much information as possible from the available data. A large number of methods founded on these concepts have been proposed in the literature, not only in biology journals, but in a wide range of areas. Their critical comparison is difficult due to the different focuses and the adoption of different terminologies. Here we attempt to review some of the existing information theoretic methodologies for network inference, and clarify their differences. While some of these methods have achieved notable success, many challenges remain, among which we can mention dealing with incomplete measurements, noisy data, counterintuitive behaviour emerging from nonlinear relations or feedback loops, and computational burden of dealing with large data sets. PMID:24709703
Callens, Nina; Van Kuyk, Maaike; van Kuppenveld, Jet H; Drop, Stenvert L S; Cohen-Kettenis, Peggy T; Dessens, Arianne B
2016-11-01
The magnitude of sex differences in human brain and behavior and the respective contributions of biology versus socialization remain a topic of ongoing study in science. The preponderance of evidence attests to the notion that sexual differentiation processes are at least partially hormonally mediated, with high levels of prenatal androgens facilitating male-typed and inhibiting female-typed behaviors. In individuals with Disorders/Differences of Sex Development (DSD), hormonal profiles or sensitivities have been altered due to genetic influences, presumably affecting gender(ed) activity interests as well as gender identity development in a minority of the affected population. While continued postnatal androgen exposure in a number of DSD syndromes has been associated with higher rates of gender dysphoria and gender change, the role of a number of mediating and moderating factors, such as initial gender assignment, syndrome severity and clinical management remains largely unclear. Limited investigations of the associations between these identified influences and gendered development outcomes impede optimization of clinical care. Participants with DSD (n=123), recruited in the context of a Dutch multi-center follow-up audit, were divided in subgroups reflecting prenatal androgen exposure, genital appearance at birth and gender of rearing. Recalled childhood play and playmate preferences, gender identity and sexual orientation were measured with questionnaires and semi-structured interviews. Data were compared to those of control male (n=46) and female participants (n=79). The findings support that (a) prenatal androgen exposure has large effects on (gendered) activity interests, but to a much lesser extent on sexual orientation and that (b) initial gender of rearing remains a better predictor of gender identity contentedness than prenatal androgen exposure, beyond syndrome severity and medical treatment influences. Nonetheless, 3.3% of individuals with DSD in our sample self-reported gender dysphoria from an early age and changed gender, which further underlines the need for thorough long- term follow-up and specific clinical support. Copyright © 2016 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Saladié, Palmira; Rodríguez-Hidalgo, Antonio; Huguet, Rosa; Cáceres, Isabel; Díez, Carlos; Vallverdú, Josep; Canals, Antoni; Soto, María; Santander, Boris; Bermúdez de Castro, José María; Arsuaga, Juan Luis; Carbonell, Eudald
2014-06-01
Pleistocene level TD6-2 of the Gran Dolina site (Sierra de Atapuerca, Spain) is the result of anthropogenic accumulation. Hominin groups occupied the cave as a home base, where they brought in, butchered and consumed the carcasses of ungulates and other hominins. In this paper, we reassess the role of carnivores in the formation and/or modification of the assemblage. We employed different methods to explore the scenario in which the TD6-2 assemblage was formed: (1) identifying the actor responsible for tooth marks; (2) determining the frequency of carnivore tooth marks and their distribution; (3) identifying the co-occurrence of modifications (butchering marks and carnivore tooth marks); (4) calculating the percentage of change and the epiphysis to shaft ratio. Carnivore tooth marks are scarce, as is the co-occurrence of hominin and carnivore modifications. However, not all tooth marks have been attributed to a particular agent due to the high equifinality between human and carnivore tooth marks. For these reasons, the frequency of tooth marks and the co-occurrence of modifications have been of little help in interpreting the role of carnivores. Axial skeletal remains and the epiphyses of the long bones are in large part missing. The percentage of change and the epiphysis to shaft ratio suggest moderate carnivore ravaging activity. Our data indicate that the role of carnivores in TD6-2 seems to have had an impact on the original assemblage after hominins had extracted a large amount of nutrients from the carcasses. Cannibalized hominin remains showed no carnivore tooth marks and have a greater presence of low survival bones compared to ungulate remains. These findings point to a different taphonomic history suggesting that TD6-2 represents a succession of settlements having different characteristics.
Some thermodynamical aspects of protein hydration water
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mallamace, Francesco, E-mail: francesco.mallamace@unime.it; Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139; Center for Polymer Studies and Department of Physics, Boston University, Boston, Massachusetts 02215
2015-06-07
We study by means of nuclear magnetic resonance the self-diffusion of protein hydration water at different hydration levels across a large temperature range that includes the deeply supercooled regime. Starting with a single hydration shell (h = 0.3), we consider different hydrations up to h = 0.65. Our experimental evidence indicates that two phenomena play a significant role in the dynamics of protein hydration water: (i) the measured fragile-to-strong dynamic crossover temperature is unaffected by the hydration level and (ii) the first hydration shell remains liquid at all hydrations, even at the lowest temperature.
Exact dynamics of a one dimensional Bose gas in a periodic time-dependent harmonic trap
NASA Astrophysics Data System (ADS)
Scopa, Stefano; Unterberger, Jéremie; Karevski, Dragi
2018-05-01
We study the unitary dynamics of a 1D gas of hard-core bosons trapped into a harmonic potential which varies periodically in time with frequency . Such periodic systems can be classified into orbits of different monodromies corresponding to two different physical situations, namely the case in which the bosonic cloud remains stable during the time-evolution and the case where it turns out to be unstable. In the present work we derive in the large particle number limit exact results for the stroboscopic evolution of the energy and particle densities in both physical situations.
Sex-role identification and violent victimization: gender differences in the role of masculinity.
Daigle, Leah E; Mummert, Sadie J
2014-01-01
Although sex-role identification has been found to be associated with crime and delinquency, the link between sex-role identification and violent victimization has remained largely unexplored. Using the Add Health data, this study examines sex-role identification and its relationship to violent victimization. The findings suggest that masculinity increases the risk of violent victimization for males, but does not for females. Other differences in risk factors across gender were also found. These findings indicate that masculinity is an important construct in understanding the complexity of why some persons are violently victimized and others are not.
Barlow, Giulia; Patterson, Julie; Stultz, Jeremy; Pakyz, Amy L
2017-12-01
Hospitals are categorized as better, no different, or worse at a national level based on their Clostridium difficile infection performance. Institutional antimicrobial stewardship programs seek to decrease the occurrence of C difficile by implementing strategies to address antibiotic usage; however, optimal structure and strategies for accomplishing this remain largely unknown. We found that a higher proportion of hospitals with either a worse or no different rank used a postprescription audit and feedback strategy than hospitals with a better rank. Copyright © 2017 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.
Conscience and Consciousness: a definition
Vithoulkas, G; Muresanu, DF
2014-01-01
While consciousness has been examined extensively in its different aspects, like in philosophy, psychiatry, neurophysiology, neuroplasticity, etc., conscience though it is an equal important aspect of the human existence, which remains an unknown to a great degree as an almost transcendental aspect of the human mind. It has not been examined as thoroughly as consciousness and largely remains a “terra incognita" for its neurophysiology, brain topography, etc. Conscience and consciousness are part of a system of information that governs our experience and decision making process. The intent of this paper is to define these terms, to discuss about consciousness from both neurological and quantum physics point of view, the relationship between the dynamics of consciousness and neuroplasticity and to highlight the relationship between conscience, stress and health. PMID:24653768
Conscience and consciousness: a definition.
Vithoulkas, G; Muresanu, D F
2014-03-15
While consciousness has been examined extensively in its different aspects, like in philosophy, psychiatry, neurophysiology, neuroplasticity, etc., conscience though it is an equal important aspect of the human existence, which remains an unknown to a great degree as an almost transcendental aspect of the human mind. It has not been examined as thoroughly as consciousness and largely remains a "terra incognita" for its neurophysiology, brain topography, etc. Conscience and consciousness are part of a system of information that governs our experience and decision making process. The intent of this paper is to define these terms, to discuss about consciousness from both neurological and quantum physics point of view, the relationship between the dynamics of consciousness and neuroplasticity and to highlight the relationship between conscience, stress and health.
Brigham, Allison R.; Sadorf, Eric M.
2001-01-01
Stream size, a reflection of basin area, was a principal influence in categorizing the benthic invertebrate assemblages, with sites that have the largest basin areas forming a separate group. Although it is difficult to distinguish among the contributions of large basin area, increased concentrations of nutrients and pesticides, and decreasing instream habitat diversity, the resulting invertebrate assemblage described was distinct. The remaining sites were headwater or tributary streams that reflected conditions more common to smaller streams, such as higher gradients and the potential for more diverse or extensive riparian habitat, but were distinguished by landform. Following basin area in importance, landform contributed to the differences observed among the benthic invertebrate communities at the remaining sites.
Complex Homology and the Evolution of Nervous Systems.
Liebeskind, Benjamin J; Hillis, David M; Zakon, Harold H; Hofmann, Hans A
2016-02-01
We examine the complex evolution of animal nervous systems and discuss the ramifications of this complexity for inferring the nature of early animals. Although reconstructing the origins of nervous systems remains a central challenge in biology, and the phenotypic complexity of early animals remains controversial, a compelling picture is emerging. We now know that the nervous system and other key animal innovations contain a large degree of homoplasy, at least on the molecular level. Conflicting hypotheses about early nervous system evolution are due primarily to differences in the interpretation of this homoplasy. We highlight the need for explicit discussion of assumptions and discuss the limitations of current approaches for inferring ancient phenotypic states. Copyright © 2015. Published by Elsevier Ltd.
Zellerhoff, Nina; Himmelbach, Axel; Dong, Wubei; Bieri, Stephane; Schaffrath, Ulrich; Schweizer, Patrick
2010-01-01
Nonhost resistance protects plants against attack by the vast majority of potential pathogens, including phytopathogenic fungi. Despite its high biological importance, the molecular architecture of nonhost resistance has remained largely unexplored. Here, we describe the transcriptional responses of one particular genotype of barley (Hordeum vulgare subsp. vulgare ‘Ingrid’) to three different pairs of adapted (host) and nonadapted (nonhost) isolates of fungal pathogens, which belong to the genera Blumeria (powdery mildew), Puccinia (rust), and Magnaporthe (blast). Nonhost resistance against each of these pathogens was associated with changes in transcript abundance of distinct sets of nonhost-specific genes, although general (not nonhost-associated) transcriptional responses to the different pathogens overlapped considerably. The powdery mildew- and blast-induced differences in transcript abundance between host and nonhost interactions were significantly correlated with differences between a near-isogenic pair of barley lines that carry either the Mlo wild-type allele or the mutated mlo5 allele, which mediates basal resistance to powdery mildew. Moreover, during the interactions of barley with the different host or nonhost pathogens, similar patterns of overrepresented and underrepresented functional categories of genes were found. The results suggest that nonhost resistance and basal host defense of barley are functionally related and that nonhost resistance to different fungal pathogens is associated with more robust regulation of complex but largely nonoverlapping sets of pathogen-responsive genes involved in similar metabolic or signaling pathways. PMID:20172964
Joint CO2 and CH4 accountability for global warming
Smith, Kirk R.; Desai, Manish A.; Rogers, Jamesine V.; Houghton, Richard A.
2013-01-01
We propose a transparent climate debt index incorporating both methane (CH4) and carbon dioxide (CO2) emissions. We develop national historic emissions databases for both greenhouse gases to 2005, justifying 1950 as the starting point for global perspectives. We include CO2 emissions from fossil sources [CO2(f)], as well as, in a separate analysis, land use change and forestry. We calculate the CO2(f) and CH4 remaining in the atmosphere in 2005 from 205 countries using the Intergovernmental Panel on Climate Change’s Fourth Assessment Report impulse response functions. We use these calculations to estimate the fraction of remaining global emissions due to each country, which is applied to total radiative forcing in 2005 to determine the combined climate debt from both greenhouse gases in units of milliwatts per square meter per country or microwatts per square meter per person, a metric we term international natural debt (IND). Australia becomes the most indebted large country per capita because of high CH4 emissions, overtaking the United States, which is highest for CO2(f). The differences between the INDs of developing and developed countries decline but remain large. We use IND to assess the relative reduction in IND from choosing between CO2(f) and CH4`control measures and to contrast the imposed versus experienced health impacts from climate change. Based on 2005 emissions, the same hypothetical impact on world 2050 IND could be achieved by decreasing CH4 emissions by 46% as stopping CO2 emissions entirely, but with substantial differences among countries, implying differential optimal strategies. Adding CH4 shifts the basic narrative about differential international accountability for climate change. PMID:23847202
Joint CO2 and CH4 accountability for global warming.
Smith, Kirk R; Desai, Manish A; Rogers, Jamesine V; Houghton, Richard A
2013-07-30
We propose a transparent climate debt index incorporating both methane (CH4) and carbon dioxide (CO2) emissions. We develop national historic emissions databases for both greenhouse gases to 2005, justifying 1950 as the starting point for global perspectives. We include CO2 emissions from fossil sources [CO2(f)], as well as, in a separate analysis, land use change and forestry. We calculate the CO2(f) and CH4 remaining in the atmosphere in 2005 from 205 countries using the Intergovernmental Panel on Climate Change's Fourth Assessment Report impulse response functions. We use these calculations to estimate the fraction of remaining global emissions due to each country, which is applied to total radiative forcing in 2005 to determine the combined climate debt from both greenhouse gases in units of milliwatts per square meter per country or microwatts per square meter per person, a metric we term international natural debt (IND). Australia becomes the most indebted large country per capita because of high CH4 emissions, overtaking the United States, which is highest for CO2(f). The differences between the INDs of developing and developed countries decline but remain large. We use IND to assess the relative reduction in IND from choosing between CO2(f) and CH4`control measures and to contrast the imposed versus experienced health impacts from climate change. Based on 2005 emissions, the same hypothetical impact on world 2050 IND could be achieved by decreasing CH4 emissions by 46% as stopping CO2 emissions entirely, but with substantial differences among countries, implying differential optimal strategies. Adding CH4 shifts the basic narrative about differential international accountability for climate change.
Brain systems for assessing the affective value of faces
Said, Christopher P.; Haxby, James V.; Todorov, Alexander
2011-01-01
Cognitive neuroscience research on facial expression recognition and face evaluation has proliferated over the past 15 years. Nevertheless, large questions remain unanswered. In this overview, we discuss the current understanding in the field, and describe what is known and what remains unknown. In §2, we describe three types of behavioural evidence that the perception of traits in neutral faces is related to the perception of facial expressions, and may rely on the same mechanisms. In §3, we discuss cortical systems for the perception of facial expressions, and argue for a partial segregation of function in the superior temporal sulcus and the fusiform gyrus. In §4, we describe the current understanding of how the brain responds to emotionally neutral faces. To resolve some of the inconsistencies in the literature, we perform a large group analysis across three different studies, and argue that one parsimonious explanation of prior findings is that faces are coded in terms of their typicality. In §5, we discuss how these two lines of research—perception of emotional expressions and face evaluation—could be integrated into a common, cognitive neuroscience framework. PMID:21536552
Interspecific utilisation of wax in comb building by honeybees
NASA Astrophysics Data System (ADS)
Hepburn, H. Randall; Radloff, Sarah E.; Duangphakdee, Orawan; Phaincharoen, Mananya
2009-06-01
Beeswaxes of honeybee species share some homologous neutral lipids; but species-specific differences remain. We analysed behavioural variation for wax choice in honeybees, calculated the Euclidean distances for different beeswaxes and assessed the relationship of Euclidean distances to wax choice. We tested the beeswaxes of Apis mellifera capensis, Apis florea, Apis cerana and Apis dorsata and the plant and mineral waxes Japan, candelilla, bayberry and ozokerite as sheets placed in colonies of A. m. capensis, A. florea and A. cerana. A. m. capensis accepted the four beeswaxes but removed Japan and bayberry wax and ignored candelilla and ozokerite. A. cerana colonies accepted the wax of A. cerana, A. florea and A. dorsata but rejected or ignored that of A. m. capensis, the plant and mineral waxes. A. florea colonies accepted A. cerana, A. dorsata and A. florea wax but rejected that of A. m. capensis. The Euclidean distances for the beeswaxes are consistent with currently prevailing phylogenies for Apis. Despite post-speciation chemical differences in the beeswaxes, they remain largely acceptable interspecifically while the plant and mineral waxes are not chemically close enough to beeswax for their acceptance.
Analysis of sequencing and scheduling methods for arrival traffic
NASA Technical Reports Server (NTRS)
Neuman, Frank; Erzberger, Heinz
1990-01-01
The air traffic control subsystem that performs scheduling is discussed. The function of the scheduling algorithms is to plan automatically the most efficient landing order and to assign optimally spaced landing times to all arrivals. Several important scheduling algorithms are described and the statistical performance of the scheduling algorithms is examined. Scheduling brings order to an arrival sequence for aircraft. First-come-first-served scheduling (FCFS) establishes a fair order, based on estimated times of arrival, and determines proper separations. Because of the randomness of the traffic, gaps will remain in the scheduled sequence of aircraft. These gaps are filled, or partially filled, by time-advancing the leading aircraft after a gap while still preserving the FCFS order. Tightly scheduled groups of aircraft remain with a mix of heavy and large aircraft. Separation requirements differ for different types of aircraft trailing each other. Advantage is taken of this fact through mild reordering of the traffic, thus shortening the groups and reducing average delays. Actual delays for different samples with the same statistical parameters vary widely, especially for heavy traffic.
A study revealing the key aroma compounds of steamed bread made by Chinese traditional sourdough*
Zhang, Guo-hua; Wu, Tao; Sadiq, Faizan A.; Yang, Huan-yi; Liu, Tong-jie; Ruan, Hui; He, Guo-qing
2016-01-01
Aroma of Chinese steamed bread (CSB) is one of the important parameters that determines the overall quality attributes and consumer acceptance. However, the aroma profile of CSB still remains poorly understood, mainly because of relying on only a single method for aroma extraction in previous studies. Therefore, the objective of this study was to determine the volatile aroma compounds of five different samples of CSB using three different aroma extraction methods, namely solid-phase microextraction (SPME), simultaneous distillation–extraction (SDE), and purge and trap (P&T). All samples showed a unique aroma profile, which could be attributed to their unique microbial consortia. (E)-2-Nonenal and (E,E)-2,4-decadienal were the most prevalent aromatic compounds revealed by SDE, which have not been reported previously, while ethanol and acetic acid proved to be the most dominant compounds by both SPME and P&T. Our approach of combining three different aroma extraction methods provided better insights into the aroma profile of CSB, which had remained largely unknown in previous studies. PMID:27704748
The predictive roles of neural oscillations in speech motor adaptability.
Sengupta, Ranit; Nasir, Sazzad M
2016-06-01
The human speech system exhibits a remarkable flexibility by adapting to alterations in speaking environments. While it is believed that speech motor adaptation under altered sensory feedback involves rapid reorganization of speech motor networks, the mechanisms by which different brain regions communicate and coordinate their activity to mediate adaptation remain unknown, and explanations of outcome differences in adaption remain largely elusive. In this study, under the paradigm of altered auditory feedback with continuous EEG recordings, the differential roles of oscillatory neural processes in motor speech adaptability were investigated. The predictive capacities of different EEG frequency bands were assessed, and it was found that theta-, beta-, and gamma-band activities during speech planning and production contained significant and reliable information about motor speech adaptability. It was further observed that these bands do not work independently but interact with each other suggesting an underlying brain network operating across hierarchically organized frequency bands to support motor speech adaptation. These results provide novel insights into both learning and disorders of speech using time frequency analysis of neural oscillations. Copyright © 2016 the American Physiological Society.
Effect of weak rotation on large-scale circulation cessations in turbulent convection.
Assaf, Michael; Angheluta, Luiza; Goldenfeld, Nigel
2012-08-17
We investigate the effect of weak rotation on the large-scale circulation (LSC) of turbulent Rayleigh-Bénard convection, using the theory for cessations in a low-dimensional stochastic model of the flow previously studied. We determine the cessation frequency of the LSC as a function of rotation, and calculate the statistics of the amplitude and azimuthal velocity fluctuations of the LSC as a function of the rotation rate for different Rayleigh numbers. Furthermore, we show that the tails of the reorientation PDF remain unchanged for rotating systems, while the distribution of the LSC amplitude and correspondingly the cessation frequency are strongly affected by rotation. Our results are in close agreement with experimental observations.
The structure and evolution of angiosperm nuclear genomes.
Bennetzen, J L
1998-04-01
Despite several decades of investigation, the organization of angiosperm genomes remained largely unknown until very recently. Data describing the sequence composition of large segments of genomes, covering hundreds of kilobases of contiguous sequence, have only become available in the past two years. Recent results indicate commonalities in the characteristics of many plant genomes, including in the structure of chromosomal components like telomeres and centromeres, and in the order and content of genes. Major differences between angiosperms have been associated mainly with repetitive DNAs, both gene families and mobile elements. Intriguing new studies have begun to characterize the dynamic three-dimensional structures of chromosomes and chromatin, and the relationship between genome structure and co-ordinated gene function.
Time drawings: Spatial representation of temporal concepts.
Leone, María Juliana; Salles, Alejo; Pulver, Alejandro; Golombek, Diego Andrés; Sigman, Mariano
2018-03-01
Time representation is a fundamental property of human cognition. Ample evidence shows that time (and numbers) are represented in space. However, how the conceptual mapping varies across individuals, scales, and temporal structures remains largely unknown. To investigate this issue, we conducted a large online study consisting in five experiments that addressed different time scales and topology: Zones of time, Seasons, Days of the week, Parts of the day and Timeline. Participants were asked to map different kinds of time events to a location in space and to determine their size and color. Results showed that time is organized in space in a hierarchical progression: some features appear to be universal (i.e. selection order), others are shaped by how time is organized in distinct cultures (i.e. location order) and, finally, some aspects vary depending on individual features such as age, gender, and chronotype (i.e. size and color). Copyright © 2018 Elsevier Inc. All rights reserved.
Supercapacitors of nanocrystalline metal-organic frameworks.
Choi, Kyung Min; Jeong, Hyung Mo; Park, Jung Hyo; Zhang, Yue-Biao; Kang, Jeung Ku; Yaghi, Omar M
2014-07-22
The high porosity of metal-organic frameworks (MOFs) has been used to achieve exceptional gas adsorptive properties but as yet remains largely unexplored for electrochemical energy storage devices. This study shows that MOFs made as nanocrystals (nMOFs) can be doped with graphene and successfully incorporated into devices to function as supercapacitors. A series of 23 different nMOFs with multiple organic functionalities and metal ions, differing pore sizes and shapes, discrete and infinite metal oxide backbones, large and small nanocrystals, and a variety of structure types have been prepared and examined. Several members of this series give high capacitance; in particular, a zirconium MOF exhibits exceptionally high capacitance. It has the stack and areal capacitance of 0.64 and 5.09 mF cm(-2), about 6 times that of the supercapacitors made from the benchmark commercial activated carbon materials and a performance that is preserved over at least 10000 charge/discharge cycles.
Habacha, Hamdi; Moreau, David; Jarraya, Mohamed; Lejeune-Poutrain, Laure; Molinaro, Corinne
2018-01-01
The effect of stimuli size on the mental rotation of abstract objects has been extensively investigated, yet its effect on the mental rotation of bodily stimuli remains largely unexplored. Depending on the experimental design, mentally rotating bodily stimuli can elicit object-based transformations, relying mainly on visual processes, or egocentric transformations, which typically involve embodied motor processes. The present study included two mental body rotation tasks requiring either a same-different or a laterality judgment, designed to elicit object-based or egocentric transformations, respectively. Our findings revealed shorter response times for large-sized stimuli than for small-sized stimuli only for greater angular disparities, suggesting that the more unfamiliar the orientations of the bodily stimuli, the more stimuli size affected mental processing. Importantly, when comparing size transformation times, results revealed different patterns of size transformation times as a function of angular disparity between object-based and egocentric transformations. This indicates that mental size transformation and mental rotation proceed differently depending on the mental rotation strategy used. These findings are discussed with respect to the different spatial manipulations involved during object-based and egocentric transformations.
Reynolds, Matthew R; Scheiber, Caroline; Hajovsky, Daniel B; Schwartz, Bryanna; Kaufman, Alan S
2015-01-01
The gender similarities hypothesis by J. S. Hyde ( 2005 ), based on large-scale reviews of studies, concludes that boys and girls are more alike than different on most psychological variables, including academic skills such as reading and math (J. S. Hyde, 2005 ). Writing is an academic skill that may be an exception. The authors investigated gender differences in academic achievement using a large, nationally stratified sample of children and adolescents ranging from ages 7-19 years (N = 2,027). Achievement data were from the conormed sample for the Kaufman intelligence and achievement tests. Multiple-indicator, multiple-cause, and multigroup mean and covariance structure models were used to test for mean differences. Girls had higher latent reading ability and higher scores on a test of math computation, but the effect sizes were consistent with the gender similarities hypothesis. Conversely, girls scored higher on spelling and written expression, with effect sizes inconsistent with the gender similarities hypothesis. The findings remained the same after controlling for cognitive ability. Girls outperform boys on tasks of writing.
3D geometric morphometric analysis of the proximal epiphysis of the hominoid humerus
Arias-Martorell, Julia; Potau, Josep Maria; Bello-Hellegouarch, Gaëlle; Pastor, Juan Francisco; Pérez-Pérez, Alejandro
2012-01-01
In this study we perform a three-dimensional geometric morphometric (3D GM) analysis of the proximal epiphysis of the humerus in extant great apes, including humans, in order to accurately describe the functional anatomical differences between these taxa. In addition, a fossil hominin specimen of Australopithecus afarensis was included in a multivariate GM analysis in order to test the potential of this methodological approach for making locomotor inferences from fossil remains. The results obtained show significant differences in proximal humeral morphology among the taxa studied, which had thus far largely remained unnoticed. Based on morphofunctional considerations, these anatomical differences can be correlated to differences in the locomotor repertoires of the taxa, thus confirming that the proximal humerus is suitable for constructing paleobiological inferences about locomotion. Modern humans display markedly divergent features, which set them apart from both the extant great apes and the fossil hominin A. afarensis. The morphology of the proximal epiphysis of the humerus of the latter more closely resembles that of the orangutans, thus suggesting that despite hindlimb adaptations to bipedalism, the forelimb of this taxon was still functionally involved in arboreal behaviors, such as climbing or suspension. PMID:22946496
Reversible cluster formation in concentrated monoclonal antibody solutions
NASA Astrophysics Data System (ADS)
Godfrin, P. Douglas; Porcar, Lionel; Falus, Peter; Zarraga, Isidro; Wagner, Norm; Liu, Yun
2015-03-01
Protein cluster formation in solution is of fundamental interest for both academic research and industrial applications. Recently, industrial scientists are also exploring the effect of reversible cluster formation on biopharmaceutical processing and delivery. However, despite of its importance, the understanding of protein clusters at concentrated solutions remains scientifically very challenging. Using the neutron spin echo technique to study the short time dynamics of proteins in solutions, we have recently systematically studied cluster formation in a few monoclonal antibody (mAb) solutions and their relation with solution viscosity. We show that the existence of anisotropic attraction can cause the formation of finite sized clusters, which increases the solution viscosity. Interestingly, once clusters form at relatively low concentrations, the average size of clusters in solutions remains almost constant over a wide range of concentrations similar to that of micelle formation. For a different mAb we have also investigated, the attraction is mostly induced by hydrophobic patches. As a result, these mAbs form large clusters with loosely linked proteins. In both cases, the formation of clusters all increases the solution viscosity substantially. However, due to different physics origins of cluster formation, solutions viscosities for these two different types of mAbs need to be controlled by different ways.
Sex differences in partner preferences in humans and animals.
Balthazart, Jacques
2016-02-19
A large number of morphological, physiological and behavioural traits are differentially expressed by males and females in all vertebrates including humans. These sex differences, sometimes, reflect the different hormonal environment of the adults, but they often remain present after subjects of both sexes are placed in the same endocrine conditions following gonadectomy associated or not with hormonal replacement therapy. They are then the result of combined influences of organizational actions of sex steroids acting early during development, or genetic differences between the sexes, or epigenetic mechanisms differentially affecting males and females. Sexual partner preference is a sexually differentiated behavioural trait that is clearly controlled in animals by the same type of mechanisms. This is also probably true in humans, even if critical experiments that would be needed to obtain scientific proof of this assertion are often impossible for pragmatic or ethical reasons. Clinical, epidemiological and correlative studies provide, however, converging evidence strongly suggesting, if not demonstrating, that endocrine, genetic and epigenetic mechanisms acting during the pre- or perinatal life control human sexual orientation, i.e. homosexuality versus heterosexuality. Whether they interact with postnatal psychosexual influences remains, however, unclear at present. © 2016 The Author(s).
Marramà, Giuseppe; Carnevale, Giorgio; Engelbrecht, Andrea; Claeson, Kerin M.; Zorzin, Roberto; Fornasiero, Mariagabriella; Kriwet, Jürgen
2018-01-01
Here, we review and discuss the records and taxonomy of the Ypresian (Eocene) chondrichthyans from the famous Bolca Konservat-Lagerstätte in northeastern Italy. Despite the outstanding diversity and the numerous studies focusing on the actinopterygian faunas from Pesciara and Monte Postale, the current knowledge about the systematics, taxonomy and phylogenetic relationships of the cartilaginous fishes from these Eocene sites remains elusive and largely inadequate. The celebrated Eocene Bolca Lagerstätte has yielded several exquisitely preserved articulated remains of chondrichthyan fishes in which delicate structures and soft tissues are preserved, as well as isolated teeth. The cartilaginous fish assemblage of Bolca comprises at least 17 species-level taxa belonging to 10 families in 6 orders, including selachians (Carcharhiniformes, Lamniformes), batoids (Torpediniformes, Myliobatiformes, Rajiformes) and holocephalans (Chimaeriformes). The occurrence of holocephalans represented by an isolated fin-spine of the chimeroid Ischyodus in the Bolca assemblage is reported here for the first time and represents the first record of chimeroids in the Eocene of Italy and also southern Europe. The Bolca chondrichthyan assemblage is remarkably different from those of other contemporaneous Boreal or Tethyan deposits, suggesting that its taxonomic composition is largely influenced by the palaeoenvironmental context. However, this synoptic review also highlights the importance of detailed revisions of all chondrichthyan remains from the Bolca Konservat-Lagerstätten.
Marramà, Giuseppe; Carnevale, Giorgio; Engelbrecht, Andrea; Claeson, Kerin M; Zorzin, Roberto; Fornasiero, Mariagabriella; Kriwet, Jürgen
2018-01-01
Here, we review and discuss the records and taxonomy of the Ypresian (Eocene) chondrichthyans from the famous Bolca Konservat-Lagerstätte in northeastern Italy. Despite the outstanding diversity and the numerous studies focusing on the actinopterygian faunas from Pesciara and Monte Postale, the current knowledge about the systematics, taxonomy and phylogenetic relationships of the cartilaginous fishes from these Eocene sites remains elusive and largely inadequate. The celebrated Eocene Bolca Lagerstätte has yielded several exquisitely preserved articulated remains of chondrichthyan fishes in which delicate structures and soft tissues are preserved, as well as isolated teeth. The cartilaginous fish assemblage of Bolca comprises at least 17 species-level taxa belonging to 10 families in 6 orders, including selachians (Carcharhiniformes, Lamniformes), batoids (Torpediniformes, Myliobatiformes, Rajiformes) and holocephalans (Chimaeriformes). The occurrence of holocephalans represented by an isolated fin-spine of the chimeroid Ischyodus in the Bolca assemblage is reported here for the first time and represents the first record of chimeroids in the Eocene of Italy and also southern Europe. The Bolca chondrichthyan assemblage is remarkably different from those of other contemporaneous Boreal or Tethyan deposits, suggesting that its taxonomic composition is largely influenced by the palaeoenvironmental context. However, this synoptic review also highlights the importance of detailed revisions of all chondrichthyan remains from the Bolca Konservat-Lagerstätten.
Food insecurity and child behavior problems in fragile families.
King, Christian
2018-02-01
Food insecurity remains a persistent problem in the United States. Several studies have shown that food insecurity is associated with child externalizing and internalizing behavior problems. However, some potential methodological limitations remain. For example, most studies use a household measure of food insecurity while there is evidence that children, especially younger ones, tend to be shielded by their parents from experiencing food insecurity. In addition, the mechanisms through which food insecurity affects children are not well understood. This study uses longitudinal data from the Fragile Families and Child Wellbeing Study to address these limitations. Fixed-effects models show that the association is even larger using a measure of child food insecurity instead of a household one. Correlated-random effects models show a large difference in child behavior problems between food secure and food insecure children due to unobserved heterogeneity. In addition, the association between child food insecurity and child externalizing behaviors remains largely unexplained while food insecurity among adults explains almost all the variation in the association with child internalizing behaviors. Food insecure children and parents are at risk of micronutrient deficiencies, which may lead to behavior problems in young children. These findings underscore the need for greater focus on reducing the risk of food insecurity, especially for children in fragile families, in order to reduce behavior problems and improve their educational attainment. Copyright © 2017 Elsevier B.V. All rights reserved.
Individual Differences, Intelligence, and Behavior Analysis
Williams, Ben; Myerson, Joel; Hale, Sandra
2008-01-01
Despite its avowed goal of understanding individual behavior, the field of behavior analysis has largely ignored the determinants of consistent differences in level of performance among individuals. The present article discusses major findings in the study of individual differences in intelligence from the conceptual framework of a functional analysis of behavior. In addition to general intelligence, we discuss three other major aspects of behavior in which individuals differ: speed of processing, working memory, and the learning of three-term contingencies. Despite recent progress in our understanding of the relations among these aspects of behavior, numerous issues remain unresolved. Researchers need to determine which learning tasks predict individual differences in intelligence and which do not, and then identify the specific characteristics of these tasks that make such prediction possible. PMID:18831127
Managing the Nuclear Fuel Cycle: Policy Implications of Expanding Global Access to Nuclear Power
2008-09-03
Spent nuclear fuel disposal has remained the most critical aspect of the nuclear fuel cycle for the United States, where longstanding nonproliferation...inalienable right and by and large, neither have U.S. government officials. However, the case of Iran raises perhaps the most critical question in...the enrichment process can take advantage of the slight difference in atomic mass between 235U and 238U. The typical enrichment process requires
An Improved Data Collection and Processing System
1988-05-01
of -use of Turbo made it the compiler of choice . These applications in- cluded data storage, processing and output. Thus, those programs...changed. As it was not envisioned that the settings would 0 87 remain constant for a large number of tests in a row, the update process is executed every...store,going); * A repeat of the above reading process is done for the file containing Ic. U:. The only difference is that the first line of this
A Waveguide Antenna with an Extended Angular Range for Remote Steering of Wave-Beam Direction
NASA Astrophysics Data System (ADS)
Sobolev, D. I.; Denisov, G. G.
2018-03-01
A new method for increasing the angular range of a waveguide antenna for remote steering of the wave-beam direction in thermonuclear-fusion experimental setups with plasma magnetic confinement is proposed. Characteristics for large beam inclination angles can be improved using the synthesized nonuniform waveguide profile. For small angles, the characteristics remain invariable, the waveguide profile differs only slightly from the regular shape, and can be fit to limited waveguide-channel sizes.
Zhong, Lena Y; Broadhurst, Roderic G
2007-02-01
This article describes a community crime prevention program in China, set against a background of rapid economic development, large internal population migration, and increasing crime rates. Traditional social control in China has been transformed to adapt to the new reform era, yet some mechanisms remain intact. Crime prevention measures and strategies resemble those adopted in the West; however, the differences, constituting the so-called Chinese characteristics with community crime prevention are significant.
A Global Catalogue of Large SO2 Sources and Emissions Derived from the Ozone Monitoring Instrument
NASA Technical Reports Server (NTRS)
Fioletov, Vitali E.; McLinden, Chris A.; Krotkov, Nickolay; Li, Can; Joiner, Joanna; Theys, Nicolas; Carn, Simon; Moran, Mike D.
2016-01-01
Sulfur dioxide (SO2) measurements from the Ozone Monitoring Instrument (OMI) satellite sensor processed with the new principal component analysis (PCA) algorithm were used to detect large point emission sources or clusters of sources. The total of 491 continuously emitting point sources releasing from about 30 kt yr(exp -1) to more than 4000 kt yr(exp -1) of SO2 per year have been identified and grouped by country and by primary source origin: volcanoes (76 sources); power plants (297); smelters (53); and sources related to the oil and gas industry (65). The sources were identified using different methods, including through OMI measurements themselves applied to a new emission detection algorithm, and their evolution during the 2005- 2014 period was traced by estimating annual emissions from each source. For volcanic sources, the study focused on continuous degassing, and emissions from explosive eruptions were excluded. Emissions from degassing volcanic sources were measured, many for the first time, and collectively they account for about 30% of total SO2 emissions estimated from OMI measurements, but that fraction has increased in recent years given that cumulative global emissions from power plants and smelters are declining while emissions from oil and gas industry remained nearly constant. Anthropogenic emissions from the USA declined by 80% over the 2005-2014 period as did emissions from western and central Europe, whereas emissions from India nearly doubled, and emissions from other large SO2-emitting regions (South Africa, Russia, Mexico, and the Middle East) remained fairly constant. In total, OMI-based estimates account for about a half of total reported anthropogenic SO2 emissions; the remaining half is likely related to sources emitting less than 30 kt yr(exp -1) and not detected by OMI.
Vullo, Carlos M; Romero, Magdalena; Catelli, Laura; Šakić, Mustafa; Saragoni, Victor G; Jimenez Pleguezuelos, María Jose; Romanini, Carola; Anjos Porto, Maria João; Puente Prieto, Jorge; Bofarull Castro, Alicia; Hernandez, Alexis; Farfán, María José; Prieto, Victoria; Alvarez, David; Penacino, Gustavo; Zabalza, Santiago; Hernández Bolaños, Alejandro; Miguel Manterola, Irati; Prieto, Lourdes; Parsons, Thomas
2016-03-01
The GHEP-ISFG Working Group has recognized the importance of assisting DNA laboratories to gain expertise in handling DVI or missing persons identification (MPI) projects which involve the need for large-scale genetic profile comparisons. Eleven laboratories participated in a DNA matching exercise to identify victims from a hypothetical conflict with 193 missing persons. The post mortem database was comprised of 87 skeletal remain profiles from a secondary mass grave displaying a minimal number of 58 individuals with evidence of commingling. The reference database was represented by 286 family reference profiles with diverse pedigrees. The goal of the exercise was to correctly discover re-associations and family matches. The results of direct matching for commingled remains re-associations were correct and fully concordant among all laboratories. However, the kinship analysis for missing persons identifications showed variable results among the participants. There was a group of laboratories with correct, concordant results but nearly half of the others showed discrepant results exhibiting likelihood ratio differences of several degrees of magnitude in some cases. Three main errors were detected: (a) some laboratories did not use the complete reference family genetic data to report the match with the remains, (b) the identity and/or non-identity hypotheses were sometimes wrongly expressed in the likelihood ratio calculations, and (c) many laboratories did not properly evaluate the prior odds for the event. The results suggest that large-scale profile comparisons for DVI or MPI is a challenge for forensic genetics laboratories and the statistical treatment of DNA matching and the Bayesian framework should be better standardized among laboratories. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Clinical diabetes research using data mining: a Canadian perspective.
Shah, Baiju R; Lipscombe, Lorraine L
2015-06-01
With the advent of the digitization of large amounts of information and the computer power capable of analyzing this volume of information, data mining is increasingly being applied to medical research. Datasets created for administration of the healthcare system provide a wealth of information from different healthcare sectors, and Canadian provinces' single-payer universal healthcare systems mean that data are more comprehensive and complete in this country than in many other jurisdictions. The increasing ability to also link clinical information, such as electronic medical records, laboratory test results and disease registries, has broadened the types of data available for analysis. Data-mining methods have been used in many different areas of diabetes clinical research, including classic epidemiology, effectiveness research, population health and health services research. Although methodologic challenges and privacy concerns remain important barriers to using these techniques, data mining remains a powerful tool for clinical research. Copyright © 2015 Canadian Diabetes Association. Published by Elsevier Inc. All rights reserved.
Crossing kingdoms: Using decellularized plants as perfusable tissue engineering scaffolds.
Gershlak, Joshua R; Hernandez, Sarah; Fontana, Gianluca; Perreault, Luke R; Hansen, Katrina J; Larson, Sara A; Binder, Bernard Y K; Dolivo, David M; Yang, Tianhong; Dominko, Tanja; Rolle, Marsha W; Weathers, Pamela J; Medina-Bolivar, Fabricio; Cramer, Carole L; Murphy, William L; Gaudette, Glenn R
2017-05-01
Despite significant advances in the fabrication of bioengineered scaffolds for tissue engineering, delivery of nutrients in complex engineered human tissues remains a challenge. By taking advantage of the similarities in the vascular structure of plant and animal tissues, we developed decellularized plant tissue as a prevascularized scaffold for tissue engineering applications. Perfusion-based decellularization was modified for different plant species, providing different geometries of scaffolding. After decellularization, plant scaffolds remained patent and able to transport microparticles. Plant scaffolds were recellularized with human endothelial cells that colonized the inner surfaces of plant vasculature. Human mesenchymal stem cells and human pluripotent stem cell derived cardiomyocytes adhered to the outer surfaces of plant scaffolds. Cardiomyocytes demonstrated contractile function and calcium handling capabilities over the course of 21 days. These data demonstrate the potential of decellularized plants as scaffolds for tissue engineering, which could ultimately provide a cost-efficient, "green" technology for regenerating large volume vascularized tissue mass. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.
Individual differences in metacontrast masking regarding sensitivity and response bias.
Albrecht, Thorsten; Mattler, Uwe
2012-09-01
In metacontrast masking target visibility is modulated by the time until a masking stimulus appears. The effect of this temporal delay differs across participants in such a way that individual human observers' performance shows distinguishable types of masking functions which remain largely unchanged for months. Here we examined whether individual differences in masking functions depend on different response criteria in addition to differences in discrimination sensitivity. To this end we reanalyzed previously published data and conducted a new experiment for further data analyses. Our analyses demonstrate that a distinction of masking functions based on the type of masking stimulus is superior to a distinction based on the target-mask congruency. Individually different masking functions are based on individual differences in discrimination sensitivities and in response criteria. Results suggest that individual differences in metacontrast masking result from individually different criterion contents. Copyright © 2012 Elsevier Inc. All rights reserved.
Ligot, Gauthier; Gourlet-Fleury, Sylvie; Ouédraogo, Dakis-Yaoba; Morin, Xavier; Bauwens, Sébastien; Baya, Fidele; Brostaux, Yves; Doucet, Jean-Louis; Fayolle, Adeline
2018-04-16
Although the importance of large trees regarding biodiversity and carbon stock in old-growth forests is undeniable, their annual contribution to biomass production and carbon uptake remains poorly studied at the stand level. To clarify the role of large trees in biomass production, we used data of tree growth, mortality, and recruitment monitored during 20 yr in 10 4-ha plots in a species-rich tropical forest (Central African Republic). Using a random block design, three different silvicultural treatments, control, logged, and logged + thinned, were applied in the 10 plots. Annual biomass gains and losses were analyzed in relation to the relative biomass abundance of large trees and by tree size classes using a spatial bootstrap procedure. Although large trees had high individual growth rates and constituted a substantial amount of biomass, stand-level biomass production decreased with the abundance of large trees in all treatments and plots. The contribution of large trees to annual stand-level biomass production appeared limited in comparison to that of small trees. This pattern did not only originate from differences in abundance of small vs. large trees or differences in initial biomass stocks among tree size classes, but also from a reduced relative growth rate of large trees and a relatively constant mortality rate among tree size classes. In a context in which large trees are increasingly gaining attention as being a valuable and a key structural characteristic of natural forests, the present study brought key insights to better gauge the relatively limited role of large trees in annual stand-level biomass production. In terms of carbon uptake, these results suggest, as already demonstrated, a low net carbon uptake of old-growth forests in comparison to that of logged forests. Tropical forests that reach a successional stage with relatively high density of large trees progressively cease to be carbon sinks as large trees contribute sparsely or even negatively to the carbon uptake at the stand level. © 2018 by the Ecological Society of America.
Chang, Shun-Chiao; Glymour, Maria; Cornelis, Marilyn; Walter, Stefan; Rimm, Eric B.; Tchetgen, Eric Tchetgen; Kawachi, Ichiro; Kubzansky, Laura D.
2017-01-01
Rationale Higher social integration is associated with lower cardiovascular mortality; however, whether it is associated with incident coronary heart disease (CHD), especially in women, and if associations differ by case fatality is unclear. Objectives This study sought to examine the associations between social integration and risk of incident CHD in a large female prospective cohort. Methods and Results 76,362 women in the Nurses’ Health Study (NHS), free of CHD and stroke at baseline (1992), were followed until 2014. Social integration was assessed by a simplified Berkman-Syme Social Network Index every 4 years. Endpoints included nonfatal myocardial infarction (MI) and fatal CHD. 2,372 incident CHD events occurred throughout follow-up. Adjusting for demographic, health/medical risk factors and depressive symptoms, being socially integrated was significantly associated with lower CHD risk, particularly fatal CHD. The most socially integrated women had a hazard ratio of 0.55 (95% confidence interval, 0.41–0.73) of developing fatal CHD compared to those least socially integrated (p-for-trend < 0.0001). When additionally adjusting for lifestyle behaviors, findings for fatal CHD were maintained but attenuated (p-for-trend = 0.02) whereas the significant associations no longer remained for nonfatal MI. The inverse associations between social integration and nonfatal MI risk were largely explained by health-promoting behaviors, particularly through differences in cigarette smoking; however, the association with fatal CHD risk remained after accounting for these behaviors and thus may involve more direct biological mechanisms. Conclusions Social integration is inversely associated with CHD incidence in women, but is largely explained by lifestyle/behavioral pathways. PMID:28373350
Sirko, Swetlana; Beckers, Johannes; Irmler, Martin
2015-01-01
Here, we review the stem cell hallmarks of endogenous neural stem cells (NSCs) during development and in some niches of the adult mammalian brain to then compare these with reactive astrocytes acquiring stem cell hallmarks after traumatic and ischemic brain injury. Notably, even endogenous NSCs including the earliest NSCs, the neuroepithelial cells, generate in most cases only a single type of progeny and self‐renew only for a rather short time in vivo. In vitro, however, especially cells cultured under neurosphere conditions reveal a larger potential and long‐term self‐renewal under the influence of growth factors. This is rather well comparable to reactive astrocytes in the traumatic or ischemic brain some of which acquire neurosphere‐forming capacity including multipotency and long‐term self‐renewal in vitro, while they remain within their astrocyte lineage in vivo. Both reactive astrocytes and endogenous NSCs exhibit stem cell hallmarks largely in vitro, but their lineage differs in vivo. Both populations generate largely a single cell type in vivo, but endogenous NSCs generate neurons and reactive astrocytes remain in the astrocyte lineage. However, at some early postnatal stages or in some brain regions reactive astrocytes can be released from this fate restriction, demonstrating that they can also enact neurogenesis. Thus, reactive astrocytes and NSCs share many characteristic hallmarks, but also exhibit key differences. This conclusion is further substantiated by genome‐wide expression analysis comparing NSCs at different stages with astrocytes from the intact and injured brain parenchyma. GLIA 2015;63:1452–1468 PMID:25965557
The European Market for Animal-Friendly Products in a Societal Context
Ingenbleek, Paul T. M.; Harvey, David; Ilieski, Vlatko; Immink, Victor M.; de Roest, Kees; Schmid, Otto
2013-01-01
Simple Summary This article takes a future focus on the direction in which social forces develop the market for animal-friendly products in Europe. Although many stakeholders believe that the market is the most viable direction to improve farm animal welfare, economic productivity of the chain remains an issue that on a fundamental level conflicts with the objective to improve animal welfare. The European market for animal-friendly products is still largely fragmented and the differences between European countries are considerable. A more animal-friendly future that is achieved through the market will therefore need substantial policy attention from stakeholders in society. Abstract This article takes a future focus on the direction in which social forces develop the market for animal-friendly products in Europe. On the basis of qualitative data gathered in the context of the European EconWelfare project, the differences across eight European countries are studied. The findings suggest that, given international trade barriers that prevent an improvement of animal welfare through legislation, many stakeholders believe that the market is the most viable direction to improve farm animal welfare. Economic productivity of the chain remains, however, an issue that on a fundamental level conflicts with the objective to improve animal welfare. With the help of a deeper conceptual understanding of willingness to pay for animal welfare, the paper finds that the European market for animal-friendly products is still largely fragmented and that the differences between European countries are considerable. A more animal-friendly future that is achieved through the market will therefore need substantial policy attention from stakeholders in society. PMID:26479535
Jones, Alex L; Kramer, Robin S S
2016-01-01
Forms of body decoration exist in all human cultures. However, in Western societies, women are more likely to engage in appearance modification, especially through the use of facial cosmetics. How effective are cosmetics at altering attractiveness? Previous research has hinted that the effect is not large, especially when compared to the variation in attractiveness observed between individuals due to differences in identity. In order to build a fuller understanding of how cosmetics and identity affect attractiveness, here we examine how professionally-applied cosmetics alter attractiveness and compare this effect with the variation in attractiveness observed between individuals. In Study 1, 33 YouTube models were rated for attractiveness before and after the application of professionally-applied cosmetics. Cosmetics explained a larger proportion of the variation in attractiveness compared with previous studies, but this effect remained smaller than variation caused by differences in attractiveness between individuals. Study 2 replicated the results of the first study with a sample of 45 supermodels, with the aim of examining the effect of cosmetics in a sample of faces with low variation in attractiveness between individuals. While the effect size of cosmetics was generally large, between-person variability due to identity remained larger. Both studies also found interactions between cosmetics and identity-more attractive models received smaller increases when cosmetics were worn. Overall, we show that professionally-applied cosmetics produce a larger effect than self-applied cosmetics, an important theoretical consideration for the field. However, the effect of individual differences in facial appearance is ultimately more important in perceptions of attractiveness.
Kramer, Robin S. S.
2016-01-01
Forms of body decoration exist in all human cultures. However, in Western societies, women are more likely to engage in appearance modification, especially through the use of facial cosmetics. How effective are cosmetics at altering attractiveness? Previous research has hinted that the effect is not large, especially when compared to the variation in attractiveness observed between individuals due to differences in identity. In order to build a fuller understanding of how cosmetics and identity affect attractiveness, here we examine how professionally-applied cosmetics alter attractiveness and compare this effect with the variation in attractiveness observed between individuals. In Study 1, 33 YouTube models were rated for attractiveness before and after the application of professionally-applied cosmetics. Cosmetics explained a larger proportion of the variation in attractiveness compared with previous studies, but this effect remained smaller than variation caused by differences in attractiveness between individuals. Study 2 replicated the results of the first study with a sample of 45 supermodels, with the aim of examining the effect of cosmetics in a sample of faces with low variation in attractiveness between individuals. While the effect size of cosmetics was generally large, between-person variability due to identity remained larger. Both studies also found interactions between cosmetics and identity–more attractive models received smaller increases when cosmetics were worn. Overall, we show that professionally-applied cosmetics produce a larger effect than self-applied cosmetics, an important theoretical consideration for the field. However, the effect of individual differences in facial appearance is ultimately more important in perceptions of attractiveness. PMID:27727311
Pope, Welkin H; Bowman, Charles A; Russell, Daniel A; Jacobs-Sera, Deborah; Asai, David J; Cresawn, Steven G; Jacobs, William R; Hendrix, Roger W; Lawrence, Jeffrey G; Hatfull, Graham F; Abbazia, Patrick; Ababio, Amma; Adam, Naazneen
2015-01-01
The bacteriophage population is large, dynamic, ancient, and genetically diverse. Limited genomic information shows that phage genomes are mosaic, and the genetic architecture of phage populations remains ill-defined. To understand the population structure of phages infecting a single host strain, we isolated, sequenced, and compared 627 phages of Mycobacterium smegmatis. Their genetic diversity is considerable, and there are 28 distinct genomic types (clusters) with related nucleotide sequences. However, amino acid sequence comparisons show pervasive genomic mosaicism, and quantification of inter-cluster and intra-cluster relatedness reveals a continuum of genetic diversity, albeit with uneven representation of different phages. Furthermore, rarefaction analysis shows that the mycobacteriophage population is not closed, and there is a constant influx of genes from other sources. Phage isolation and analysis was performed by a large consortium of academic institutions, illustrating the substantial benefits of a disseminated, structured program involving large numbers of freshman undergraduates in scientific discovery. DOI: http://dx.doi.org/10.7554/eLife.06416.001 PMID:25919952
Pope, Welkin H; Bowman, Charles A; Russell, Daniel A; Jacobs-Sera, Deborah; Asai, David J; Cresawn, Steven G; Jacobs, William R; Hendrix, Roger W; Lawrence, Jeffrey G; Hatfull, Graham F
2015-04-28
The bacteriophage population is large, dynamic, ancient, and genetically diverse. Limited genomic information shows that phage genomes are mosaic, and the genetic architecture of phage populations remains ill-defined. To understand the population structure of phages infecting a single host strain, we isolated, sequenced, and compared 627 phages of Mycobacterium smegmatis. Their genetic diversity is considerable, and there are 28 distinct genomic types (clusters) with related nucleotide sequences. However, amino acid sequence comparisons show pervasive genomic mosaicism, and quantification of inter-cluster and intra-cluster relatedness reveals a continuum of genetic diversity, albeit with uneven representation of different phages. Furthermore, rarefaction analysis shows that the mycobacteriophage population is not closed, and there is a constant influx of genes from other sources. Phage isolation and analysis was performed by a large consortium of academic institutions, illustrating the substantial benefits of a disseminated, structured program involving large numbers of freshman undergraduates in scientific discovery.
NASA Astrophysics Data System (ADS)
Li, Faxin; Wang, Qiangzhong; Miao, Hongchen
2017-08-01
The widely used ferroelectric ceramics based actuators always suffer from small output strains (typically ˜0.1%-0.15%). Non-180° domain switching can generate a large strain in ferroelectrics but it is usually irreversible. In this work, we tailored the domain structures in a soft lead titanate zirconate (PZT) ceramic by periodical orthogonal poling. The non-180° switching in this domain-engineered PZT ceramics turns to be reversible, resulting in a local giant actuation strain of nearly 0.6% under a field of 2 kV/mm at 0.1 Hz. The large interfacial stresses between regions with different poling directions during electric loading/unloading were thought to be responsible for the reversible non-180° domain switching. The switching strain drops quickly with the increasing frequency, and stabilized at about 0.2% at or above 1.0 Hz. The large actuation strain remains quite stable after 104 cycles of loading, which is very promising for low-frequency, large-strain actuators.
Planning as an Iterative Process
NASA Technical Reports Server (NTRS)
Smith, David E.
2012-01-01
Activity planning for missions such as the Mars Exploration Rover mission presents many technical challenges, including oversubscription, consideration of time, concurrency, resources, preferences, and uncertainty. These challenges have all been addressed by the research community to varying degrees, but significant technical hurdles still remain. In addition, the integration of these capabilities into a single planning engine remains largely unaddressed. However, I argue that there is a deeper set of issues that needs to be considered namely the integration of planning into an iterative process that begins before the goals, objectives, and preferences are fully defined. This introduces a number of technical challenges for planning, including the ability to more naturally specify and utilize constraints on the planning process, the ability to generate multiple qualitatively different plans, and the ability to provide deep explanation of plans.
Injectable nanocarriers for biodetoxification
NASA Astrophysics Data System (ADS)
Leroux, Jean-Christophe
2007-11-01
Hospitals routinely treat patients suffering from overdoses of drugs or other toxic chemicals as a result of illicit drug consumption, suicide attempts or accidental exposures. However, for many life-threatening situations, specific antidotes are not available and treatment is largely based on emptying the stomach, administering activated charcoal or other general measures of intoxication support. A promising strategy for managing such overdoses is to inject nanocarriers that can extract toxic agents from intoxicated tissues. To be effective, the nanocarriers must remain in the blood long enough to sequester the toxic components and/or their metabolites, and the toxin bound complex must also remain stable until it is removed from the bloodstream. Here, we discuss the principles that govern the use of injectable nanocarriers in biodetoxification and review the pharmacological performance of a number of different approaches.
Structural Connectivity of the Developing Human Amygdala
Saygin, Zeynep M.; Osher, David E.; Koldewyn, Kami; Martin, Rebecca E.; Finn, Amy; Saxe, Rebecca; Gabrieli, John D.E.; Sheridan, Margaret
2015-01-01
A large corpus of research suggests that there are changes in the manner and degree to which the amygdala supports cognitive and emotional function across development. One possible basis for these developmental differences could be the maturation of amygdalar connections with the rest of the brain. Recent functional connectivity studies support this conclusion, but the structural connectivity of the developing amygdala and its different nuclei remains largely unstudied. We examined age related changes in the DWI connectivity fingerprints of the amygdala to the rest of the brain in 166 individuals of ages 5-30. We also developed a model to predict age based on individual-subject amygdala connectivity, and identified the connections that were most predictive of age. Finally, we segmented the amygdala into its four main nucleus groups, and examined the developmental changes in connectivity for each nucleus. We observed that with age, amygdalar connectivity becomes increasingly sparse and localized. Age related changes were largely localized to the subregions of the amygdala that are implicated in social inference and contextual memory (the basal and lateral nuclei). The central nucleus’ connectivity also showed differences with age but these differences affected fewer target regions than the basal and lateral nuclei. The medial nucleus did not exhibit any age related changes. These findings demonstrate increasing specificity in the connectivity patterns of amygdalar nuclei across age. PMID:25875758
Actin and microtubule networks contribute differently to cell response for small and large strains
NASA Astrophysics Data System (ADS)
Kubitschke, H.; Schnauss, J.; Nnetu, K. D.; Warmt, E.; Stange, R.; Kaes, J.
2017-09-01
Cytoskeletal filaments provide cells with mechanical stability and organization. The main key players are actin filaments and microtubules governing a cell’s response to mechanical stimuli. We investigated the specific influences of these crucial components by deforming MCF-7 epithelial cells at small (≤5% deformation) and large strains (>5% deformation). To understand specific contributions of actin filaments and microtubules, we systematically studied cellular responses after treatment with cytoskeleton influencing drugs. Quantification with the microfluidic optical stretcher allowed capturing the relative deformation and relaxation of cells under different conditions. We separated distinctive deformational and relaxational contributions to cell mechanics for actin and microtubule networks for two orders of magnitude of drug dosages. Disrupting actin filaments via latrunculin A, for instance, revealed a strain-independent softening. Stabilizing these filaments by treatment with jasplakinolide yielded cell softening for small strains but showed no significant change at large strains. In contrast, cells treated with nocodazole to disrupt microtubules displayed a softening at large strains but remained unchanged at small strains. Stabilizing microtubules within the cells via paclitaxel revealed no significant changes for deformations at small strains, but concentration-dependent impact at large strains. This suggests that for suspended cells, the actin cortex is probed at small strains, while at larger strains; the whole cell is probed with a significant contribution from the microtubules.
Tran, Ulrich S.; Hofer, Agnes A.; Voracek, Martin
2014-01-01
Research from various countries consistently reported an advantage of boys over girls in general knowledge and was also suggestive of some overall trends regarding specific domains of general knowledge that were speculated to stem from biologically differentiated interests. However, results were heterogeneous and, as of yet, had not been evaluated meta-analytically. Moreover, previous research drew on overly homogeneous high-school or undergraduate samples whose representativeness appears problematic; mostly, likely moderators, such as school type, student age or parental education, were also not directly investigated or controlled for. We provide a meta-analytical aggregation of available results regarding sex differences in general knowledge and present new data, investigating the psychometric properties of the General Knowledge Test (GKT), on which previous research primarily relied, and explored sex differences in a large and heterogeneous Austrian high-school student sample (N = 1088). The aggregated sex effect in general knowledge was of medium size in previous research, but differences in specific domains were heterogeneous across countries and only modest at best. Large sex differences in our data could be explained to a large part by school-related moderators (school type, school, student age, parental education) and selection processes. Boys had a remaining advantage over girls that was only small in size and that was consistent with the magnitude of sex differences in general intelligence. Analysis of the GKT yielded no evidence of biologically differentiated interests, but of a specific interest in the humanities among girls. In conclusion, previous research likely overestimated sex differences in general knowledge. PMID:25347190
Tran, Ulrich S; Hofer, Agnes A; Voracek, Martin
2014-01-01
Research from various countries consistently reported an advantage of boys over girls in general knowledge and was also suggestive of some overall trends regarding specific domains of general knowledge that were speculated to stem from biologically differentiated interests. However, results were heterogeneous and, as of yet, had not been evaluated meta-analytically. Moreover, previous research drew on overly homogeneous high-school or undergraduate samples whose representativeness appears problematic; mostly, likely moderators, such as school type, student age or parental education, were also not directly investigated or controlled for. We provide a meta-analytical aggregation of available results regarding sex differences in general knowledge and present new data, investigating the psychometric properties of the General Knowledge Test (GKT), on which previous research primarily relied, and explored sex differences in a large and heterogeneous Austrian high-school student sample (N = 1088). The aggregated sex effect in general knowledge was of medium size in previous research, but differences in specific domains were heterogeneous across countries and only modest at best. Large sex differences in our data could be explained to a large part by school-related moderators (school type, school, student age, parental education) and selection processes. Boys had a remaining advantage over girls that was only small in size and that was consistent with the magnitude of sex differences in general intelligence. Analysis of the GKT yielded no evidence of biologically differentiated interests, but of a specific interest in the humanities among girls. In conclusion, previous research likely overestimated sex differences in general knowledge.
Peirce, E J; Breed, W G
1990-05-01
The organization of testicular interstitial tissue of the spinifex hopping mouse, Notomys alexis differs from that of other rodents. It comprises between 10.3% and 17.3% (average 15.0%) of the total testicular volume, and is variable in its organization both at different locations within the testis of the one animal and among different individuals. Abundant, closely packed Leydig cells are usually present; however, in some regions large, thick-walled blood vessels and extensive peritubular lymphatic spaces, often lacking an endothelium adjacent to the Leydig cells, are also prominent. The Leydig cells in contact with the large blood vessels and lymphatics, unlike those in regions where lymph is sparse, are not densely packed and sometimes contain numerous lipid droplets. Ultrastructure of Leydig cells is typical of steroid-producing cells; however, mitochondria are often extremely large, unusual in shape or bizarrely arranged in relation to one another. Also electron-dense bodies displaying a paracrystalline-like internal structure of parallel, electron-dense filaments arranged in a lattice pattern occur in the cytoplasm of many cells. The significance of these unusual ultrastructural features and the organization of the interstitial tissue remain to be determined conclusively, but may relate to steroid synthesis, secretion and uptake.
Large-scale transport across narrow gaps in rod bundles
DOE Office of Scientific and Technical Information (OSTI.GOV)
Guellouz, M.S.; Tavoularis, S.
1995-09-01
Flow visualization and how-wire anemometry were used to investigate the velocity field in a rectangular channel containing a single cylindrical rod, which could be traversed on the centreplane to form gaps of different widths with the plane wall. The presence of large-scale, quasi-periodic structures in the vicinity of the gap has been demonstrated through flow visualization, spectral analysis and space-time correlation measurements. These structures are seen to exist even for relatively large gaps, at least up to W/D=1.350 (W is the sum of the rod diameter, D, and the gap width). The above measurements appear to compatible with the fieldmore » of a street of three-dimensional, counter-rotating vortices, whose detailed structure, however, remains to be determined. The convection speed and the streamwise spacing of these vortices have been determined as functions of the gap size.« less
Stability issues pertaining large area perovskite and dye-sensitized solar cells and modules
NASA Astrophysics Data System (ADS)
Castro-Hermosa, S.; Yadav, S. K.; Vesce, L.; Guidobaldi, A.; Reale, A.; Di Carlo, A.; Brown, T. M.
2017-01-01
Perovskite and dye-sensitized solar cells are PV technologies which hold promise for PV application. Arguably, the biggest issue facing these technologies is stability. The vast majority of studies have been limited to small area laboratory cells. Moisture, oxygen, UV light, thermal and electrical stresses are leading the degradation causes. There remains a shortage of stability investigations on large area devices, in particular modules. At the module level there exist particular challenges which can be different from those at the small cell level such as encapsulation (not only of the unit cells but of interconnections and contacts), non-uniformity of the layer stacks and unit cells, reverse bias stresses, which are important to investigate for technologies that aim for industrial acceptance. Herein we present a review of stability investigations published in the literature pertaining large area perovskite and dye-sensitized solar devices fabricated both on rigid (glass) and flexible substrates.
NASA Astrophysics Data System (ADS)
Peruani, Fernando
2016-11-01
Bacteria, chemically-driven rods, and motility assays are examples of active (i.e. self-propelled) Brownian rods (ABR). The physics of ABR, despite their ubiquity in experimental systems, remains still poorly understood. Here, we review the large-scale properties of collections of ABR moving in a dissipative medium. We address the problem by presenting three different models, of decreasing complexity, which we refer to as model I, II, and III, respectively. Comparing model I, II, and III, we disentangle the role of activity and interactions. In particular, we learn that in two dimensions by ignoring steric or volume exclusion effects, large-scale nematic order seems to be possible, while steric interactions prevent the formation of orientational order at large scales. The macroscopic behavior of ABR results from the interplay between active stresses and local alignment. ABR exhibit, depending on where we locate ourselves in parameter space, a zoology of macroscopic patterns that ranges from polar and nematic bands to dynamic aggregates.
Management of fish populations in large rivers: a review of tools and approaches
Petts, Geoffrey E.; Imhoff, Jack G.; Manny, Bruce A.; Maher, John F. B.; Weisberg, Stephen B.
1989-01-01
In common with most branches of science, the management of riverine fish populations is characterised by reductionist and isolationist philosophies. Traditional fish management focuses on stocking and controls on fishing. This paper presents a concensus of scientists involved in the LARS workshop on the management of fish populations in large rivers. A move towards a more holistic philosophy is advocated, with fish management forming an integral part of sustainable river development. Based upon a questionnaire survey of LARS members, with wide-ranging expertise and experience from all parts of the world, lists of management tools currently in use are presented. Four categories of tools are described: flow, water-quality, habitat, and biological. The potential applications of tools for fish management in large rivers is discussed and research needs are identified. The lack of scientific evaluations of the different tools remains the major constraint to their wider application.
Broca's area: a supramodal hierarchical processor?
Tettamanti, Marco; Weniger, Dorothea
2006-05-01
Despite the presence of shared characteristics across the different domains modulating Broca's area activity (e.g., structural analogies, as between language and music, or representational homologies, as between action execution and action observation), the question of what exactly the common denominator of such diverse brain functions is, with respect to the function of Broca's area, remains largely a debated issue. Here, we suggest that an important computational role of Broca's area may be to process hierarchical structures in a wide range of functional domains.
Analysis of Growth and Molecular Responses to Ethylene in Etiolated Rice Seedlings.
Ma, Biao; Zhang, Jin-Song
2017-01-01
Ethylene plays a key role in various submergence responses of rice plants, but the mechanism of ethylene action remains largely unclear in rice. Regarding the differences between rice and Arabidopsis in ethylene-regulated processes, rice plants may possess divergent mechanisms in ethylene signaling in addition to the conserved aspects. Forward genetic analysis is essential to fully understand the ethylene signaling mechanism in rice. Here, we describe a method for screening ethylene-response mutants and evaluating ethylene responsiveness in etiolated rice seedlings.
Porciani, David; Cardwell, Leah N; Tawiah, Kwaku D; Alam, Khalid K; Lange, Margaret J; Daniels, Mark A; Burke, Donald H
2018-06-11
Large RNAs and ribonucleoprotein complexes have powerful therapeutic potential, but effective cell-targeted delivery tools are limited. Aptamers that internalize into target cells can deliver siRNAs (<15 kDa, 19-21 nt/strand). We demonstrate a modular nanostructure for cellular delivery of large, functional RNA payloads (50-80 kDa, 175-250 nt) by aptamers that recognize multiple human B cell cancer lines and transferrin receptor-expressing cells. Fluorogenic RNA reporter payloads enable accelerated testing of platform designs and rapid evaluation of assembly and internalization. Modularity is demonstrated by swapping in different targeting and payload aptamers. Both modules internalize into leukemic B cell lines and remained colocalized within endosomes. Fluorescence from internalized RNA persists for ≥2 h, suggesting a sizable window for aptamer payloads to exert influence upon targeted cells. This demonstration of aptamer-mediated, cell-internalizing delivery of large RNAs with retention of functional structure raises the possibility of manipulating endosomes and cells by delivering large aptamers and regulatory RNAs.
Exergy Analysis of the Cryogenic Helium Distribution System for the Large Hadron Collider (lhc)
NASA Astrophysics Data System (ADS)
Claudet, S.; Lebrun, Ph.; Tavian, L.; Wagner, U.
2010-04-01
The Large Hadron Collider (LHC) at CERN features the world's largest helium cryogenic system, spreading over the 26.7 km circumference of the superconducting accelerator. With a total equivalent capacity of 145 kW at 4.5 K including 18 kW at 1.8 K, the LHC refrigerators produce an unprecedented exergetic load, which must be distributed efficiently to the magnets in the tunnel over the 3.3 km length of each of the eight independent sectors of the machine. We recall the main features of the LHC cryogenic helium distribution system at different temperature levels and present its exergy analysis, thus enabling to qualify second-principle efficiency and identify main remaining sources of irreversibility.
NASA Astrophysics Data System (ADS)
Li, Hsiang-Nan; Mishima, Satoshi; Sanda, A. I.
2005-12-01
We calculate the important next-to-leading-order contributions to the B→πK, ππ decays from the vertex corrections, the quark loops, and the magnetic penguins in the perturbative QCD approach. It is found that the latter two reduce the leading-order penguin amplitudes by about 10% and modify only the B→πK branching ratios. The main effect of the vertex corrections is to increase the small color-suppressed tree amplitude by a factor of 3, which then resolves the large difference between the direct CP asymmetries of the B0→π∓K± and B±→π0K± modes. The puzzle from the large B0→π0π0 branching ratio still remains.
Phenomenology with fluctuating quantum geometries in loop quantum cosmology
NASA Astrophysics Data System (ADS)
Agullo, Ivan; Ashtekar, Abhay; Gupt, Brajesh
2017-04-01
The goal of this paper is to probe phenomenological implications of large fluctuations of quantum geometry in the Planck era, using cosmology of the early universe. For the background (Friedmann, Lemaître, Robertson, Walker) quantum geometry, we allow ‘widely spread’ states in which the relative dispersions are as large as 168 % in the Planck regime. By introducing suitable methods to overcome the ensuing conceptual and computational issues, we calculate the power spectrum {{P}R}(k) and the spectral index n s (k) of primordial curvature perturbations. These results generalize the previous work in loop quantum cosmology which focused on those states which were known to remain sharply peaked throughout the Planck regime. Surprisingly, even though the fluctuations we now consider are large, their presence does not add new features to the final {{P}R}(k) and n s (k): within observational error bars, their effect is degenerate with a different freedom in the theory, namely the number of pre-inflationary e-folds {{N}\\text{B\\star}} between the bounce and the onset of inflation. Therefore, with regard to observational consequences, one can simulate the freedom in the choice of states with large fluctuations in the Planck era using the simpler, sharply peaked states, simply by allowing for different values of {{N}\\text{B \\star}} .
Biodegradation and flushing of MBT wastes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Siddiqui, A.A., E-mail: aasiddiqui.cv@amu.ac.in; Richards, D.J.; Powrie, W.
Highlights: • Stabilization was achieved for MBT wastes of different degrees of pretreatment. • About 92% reduction in the gas generation compared with raw MSW. • Pretreatment resulted in reduced TOC, nitrogen and heavy metals in leachate. • A large proportion of carbon and nitrogen remained in the waste material. - Abstract: Mechanical–biological treatment (MBT) processes are increasingly being adopted as a means of diverting biodegradable municipal waste (BMW) from landfill, for example to comply with the EU Landfill Directive. However, there is considerable uncertainty concerning the residual pollution potential of such wastes. This paper presents the results of laboratorymore » experiments on two different MBT waste residues, carried out to investigate the remaining potential for the generation of greenhouse gases and the flushing of contaminants from these materials when landfilled. The potential for gas generation was found to be between 8% and 20% of that for raw MSW. Pretreatment of the waste reduced the potential for the release of organic carbon, ammoniacal nitrogen, and heavy metal contents into the leachate; and reduced the residual carbon remaining in the waste after final degradation from ∼320 g/kg dry matter for raw MSW to between 183 and 195 g/kg dry matter for the MBT wastes.« less
Woods, Jeremy; Williams, Adrian; Hughes, John K; Black, Mairi; Murphy, Richard
2010-09-27
Modern agriculture is heavily dependent on fossil resources. Both direct energy use for crop management and indirect energy use for fertilizers, pesticides and machinery production have contributed to the major increases in food production seen since the 1960s. However, the relationship between energy inputs and yields is not linear. Low-energy inputs can lead to lower yields and perversely to higher energy demands per tonne of harvested product. At the other extreme, increasing energy inputs can lead to ever-smaller yield gains. Although fossil fuels remain the dominant source of energy for agriculture, the mix of fuels used differs owing to the different fertilization and cultivation requirements of individual crops. Nitrogen fertilizer production uses large amounts of natural gas and some coal, and can account for more than 50 per cent of total energy use in commercial agriculture. Oil accounts for between 30 and 75 per cent of energy inputs of UK agriculture, depending on the cropping system. While agriculture remains dependent on fossil sources of energy, food prices will couple to fossil energy prices and food production will remain a significant contributor to anthropogenic greenhouse gas emissions. Technological developments, changes in crop management, and renewable energy will all play important roles in increasing the energy efficiency of agriculture and reducing its reliance of fossil resources.
Woods, Jeremy; Williams, Adrian; Hughes, John K.; Black, Mairi; Murphy, Richard
2010-01-01
Modern agriculture is heavily dependent on fossil resources. Both direct energy use for crop management and indirect energy use for fertilizers, pesticides and machinery production have contributed to the major increases in food production seen since the 1960s. However, the relationship between energy inputs and yields is not linear. Low-energy inputs can lead to lower yields and perversely to higher energy demands per tonne of harvested product. At the other extreme, increasing energy inputs can lead to ever-smaller yield gains. Although fossil fuels remain the dominant source of energy for agriculture, the mix of fuels used differs owing to the different fertilization and cultivation requirements of individual crops. Nitrogen fertilizer production uses large amounts of natural gas and some coal, and can account for more than 50 per cent of total energy use in commercial agriculture. Oil accounts for between 30 and 75 per cent of energy inputs of UK agriculture, depending on the cropping system. While agriculture remains dependent on fossil sources of energy, food prices will couple to fossil energy prices and food production will remain a significant contributor to anthropogenic greenhouse gas emissions. Technological developments, changes in crop management, and renewable energy will all play important roles in increasing the energy efficiency of agriculture and reducing its reliance of fossil resources. PMID:20713398
Rapid encoding of relationships between spatially remote motion signals.
Maruya, Kazushi; Holcombe, Alex O; Nishida, Shin'ya
2013-02-06
For visual processing, the temporal correlation of remote local motion signals is a strong cue to detect meaningful large-scale structures in the retinal image, because related points are likely to move together regardless of their spatial separation. While the processing of multi-element motion patterns involved in biological motion and optic flow has been studied intensively, the encoding of simpler pairwise relationships between remote motion signals remains poorly understood. We investigated this process by measuring the temporal rate limit for perceiving the relationship of two motion directions presented at the same time at different spatial locations. Compared to luminance or orientation, motion comparison was more rapid. Performance remained very high even when interstimulus separation was increased up to 100°. Motion comparison also remained rapid regardless of whether the two motion directions were similar to or different from each other. The exception was a dramatic slowing when the elements formed an orthogonal "T," in which two motions do not perceptually group together. Motion presented at task-irrelevant positions did not reduce performance, suggesting that the rapid motion comparison could not be ascribed to global optic flow processing. Our findings reveal the existence and unique nature of specialized processing that encodes long-range relationships between motion signals for quick appreciation of global dynamic scene structure.
Ghemawat, Pankaj
2003-11-01
Most multinationals see globalization as a matter of replication--spreading a single business model as widely as possible to maximize economies of scale. From this perspective, the key strategic challenge is choosing how much of the model to keep standard and how much to grudgingly adapt to local tastes. But focusing exclusively on that choice is a mistake, for it blinds companies to the very real opportunities they can still gain from arbitrage--from exploiting differences as opposed to similarities. Indeed, the scope for arbitrage is as wide as the differences that remain among countries, and those differences continue to be broad and deep. They can, in fact, be divided into four main categories--cultural, administrative, economic, and geographic. In each category, old opportunities persist and new ones are arising, sometimes very quickly. Consider the continued cachet of French culture in its wines and haute couture. Witness, too, how swiftly the Finns have become known for their expertise in wireless communications. Clearly, legal and other administrative differences, particularly in tax laws and the cost of capital, remain large. So do purely economic wage differentials, especially for knowledge workers and other skilled employees. And if modern transportation and other technologies have reduced geographic advantages and brought down the price of spices, they've also made possible expanded trade in other goods like perishable flowers and out-of-season produce. Both the differences that make arbitrage valuable and the similarities that make replication important will remain with us for the foreseeable future, and combining the two, while necessary, is tricky. But that spells competitive advantage for those companies that have the imagination to see the full range of possibilities.
Diabetes prevalence based on health insurance claims: large differences between companies.
Hoffmann, F; Icks, A
2011-08-01
We investigated if there are substantial differences in the prevalence of diabetes between members of different health insurance funds in Germany and, if so, which variables might explain these differences. Ten representative surveys (conducted between 2004 and 2008) of the Bertelsmann Healthcare Monitor, comprising 15 089 participants aged 18-79 years, were analysed. Our main independent variable was membership in one of eight health insurance funds. We first estimated the crude prevalence of diabetes stratified by these funds. We further fitted logistic regression models and stepwise adjusted for age and sex, further co-morbidities and anthropometric measures and factors influencing health awareness and lifestyle. The overall prevalence of diabetes was 6.9%. Stratified by health insurance funds, prevalences ranged between 3.9% within the Innungskrankenkassen to 11.4% within the Allgemeine Ortskrankenkassen. Adjusting for age and sex only led to minor changes. After controlling for all mentioned variables, these differences remained. Compared with those who were privately insured, persons within the Allgemeine Ortskrankenkassen (OR 1.73; 95% CI 1.30-2.29), the Betriebskrankenkassen (OR 1.54; 95% CI 1.15-2.07) and the Barmer (OR 1.39; 95% CI 1.01-1.91) had a higher prevalence. We found considerable differences in diabetes prevalence between German health insurance funds that remained after controlling for several relevant variables. © 2011 The Authors. Diabetic Medicine © 2011 Diabetes UK.
Kim, Hyunjee; McConnell, K John; Sun, Benjamin C
2017-08-01
The high rate of emergency department (ED) use by Medicaid patients is not fully understood. The objective of this paper is (1) to provide context for ED service use by comparing Medicaid and commercial patients' differences across ED and non-ED health service use, and (2) to assess the extent to which Medicaid-commercial differences in ED use can be explained by observable factors in administrative data. Statistical decomposition methods were applied to ED, mental health, and inpatient care using 2011-2013 Medicaid and commercial insurance claims from the Oregon All Payer All Claims database. Demographics, comorbidities, health services use, and neighborhood characteristics accounted for 44% of the Medicaid-commercial difference in ED use, compared to 83% for mental health care and 75% for inpatient care. This suggests that relative to mental health and inpatient care, a large portion of ED use cannot be explained by administrative data. Models that further accounted for patient access to different primary care physicians explained an additional 8% of the Medicaid-commercial difference in ED use, suggesting that the quality of primary care may influence ED use. The remaining unexplained difference suggests that appropriately reducing ED use remains a credible target for policy makers, although success may require knowledge about patients' perceptions and behaviors as well as social determinants of health.
Mascherek, Anna C; Schwappach, David L B
2017-01-01
Safety Climate has been acknowledged as an unspecific factor influencing patient safety. However, studies rarely provide in-depth analysis of climate data. As a helpful approach, the concept of "climate strength" has been proposed. In the present study we tested the hypotheses that even if safety climate remains stable on mean-level across time, differences might be evident in strength or shape. The data of two hospitals participating in a large national quality improvement program were analysed for differences in climate profiles at two measurement occasions. We analysed differences on mean-level, differences in percent problematic response, agreement within groups, and frequency histograms in two large hospitals in Switzerland at two measurement occasions (2013 and 2015) applying the Safety Climate Survey. In total, survey responses of 1193 individuals were included in the analyses. Overall, small but significant differences on mean-level of safety climate emerged for some subgroups. Also, although agreement was strong at both time-points within groups, tendencies of divergence or consensus were present in both hospitals. Depending on subgroup and analyses chosen, differences were more or less pronounced. The present study illustrated that taking several measures into account and describing safety climate from different perspectives is necessary in order to fully understand differences and trends within groups and to develop interventions addressing the needs of different groups more precisely.
Development costs of reusable launch vehicles
NASA Astrophysics Data System (ADS)
Koelle, D.
2002-07-01
The paper deals first with the definition and understanding of "Development Costs" in general. Usually there is large difference between initial "development cost guesses", "Proposal Cost Estimations" and the final "Cost-to-Completion". The reasons for the usual development cost increases during development are discussed. The second part discusses the range of historic launch systems' development costs under "Business-as-Usual" (BaU) - Conditions and potential cost reductions for future developments of RLVs, as well as the comparison to commercial, industrial development cost. Part three covers the potential reduction of development cost by application of "Cost Engineering Principles". An example of the large potential cost range (between 6 and 17 Billion USD) for the development of the same winged rocket-propelled SSTO launch vehicle concept is presented. Finally the tremendous development cost differences are shown which exist for the different potential Reusable Launch System Options which are under discussion. There remains an unresolved problem between the primary goals of the national space agencies with emphasis on new technology development/national prestige and the commercial market requirement of a simple low-cost RLV-System.
Metaphorically speaking: cognitive abilities and the production of figurative language.
Beaty, Roger E; Silvia, Paul J
2013-02-01
Figurative language is one of the most common expressions of creative behavior in everyday life. However, the cognitive mechanisms behind figures of speech such as metaphors remain largely unexplained. Recent evidence suggests that fluid and executive abilities are important to the generation of conventional and creative metaphors. The present study investigated whether several factors of the Cattell-Horn-Carroll model of intelligence contribute to generating these different types of metaphors. Specifically, the roles of fluid intelligence (Gf), crystallized intelligence (Gc), and broad retrieval ability (Gr) were explored. Participants completed a series of intelligence tests and were asked to produce conventional and creative metaphors. Structural equation modeling was used to assess the contribution of the different factors of intelligence to metaphor production. For creative metaphor, there were large effects of Gf (β = .45) and Gr (β = .52); for conventional metaphor, there was a moderate effect of Gc (β = .30). Creative and conventional metaphors thus appear to be anchored in different patterns of abilities: Creative metaphors rely more on executive processes, whereas conventional metaphors primarily draw from acquired vocabulary knowledge.
Li, Huan; Liu, Xiangsheng; Huang, Nan; Ren, Kefeng; Jin, Qiao; Ji, Jian
2014-01-01
The acidic microenvironment of tumor tissues has proven to be one of the major differences from other normal tissues. The near-infrared (NIR) light irradiation of aggregated gold nanoparticles in a tumor acidic pH-induced manner could then provide an effect approach to treat solid tumors with the advantage of minimizing the undesired damage to normal tissues. Although it is well-known the aggregation of larger nanoparticles will result in a better NIR photothermal effect, the preparation of pH-sensitive gold nanoparticles in large sizes remains a big challenge because of their worse dispersive stability. In this paper, we introduce a facile way to endow large gold nanoparticles with tunable pH-aggregation behaviors by modifying the nanoparticle surface with mixed-charge self-assembly monolayers compromising positively and negatively charged thiol ligands. Four different size nanoparticles were used to study the general principle of tailoring the pH-induced aggregation behaviors of mixed-charge gold nanoparticles (MC-GNPs) by adjusting the surface ligand composition. With proper surface ligand composition, the MC-GNPs in four different sizes that all exhibited aggregation at tumor acidic pH were obtained. The biggest MC-GNPs showed the most encouraging aggregation-enhanced photothermal efficacy in vitro when they formed aggregates. The mixed-charge self-assembled monolayers were then proved as a facile method to design pH-induced aggregation of large gold nanoparticles for better NIR photothermal cancer therapy.
Effect of large wood retention at check dams on sediment continuity
NASA Astrophysics Data System (ADS)
Schmocker, Lukas; Schalko, Isabella; Weitbrecht, Volker
2017-04-01
Large wood transport during flood events may seriously increase the damage potential due to accumulations at river infrastructures. The large wood is therefore mostly retained upstream of populated areas using retention structures that often combine a check dam with a debris rack. One disadvantages of this structures is, that the bed-load gets retained along with the wood. Especially if large wood blocks the rack early during a flood event, sediment continuity is completely interrupted. This may lead to severe bed erosion downstream of the check dam. So far, no common design to retain large wood but maintain sediment continuity is available. One attempt to separate the large wood from the bed-load was made with the large wood retention structure at River Sihl in Zürich, Switzerland. The retention of the large wood occurs in a bypass channel located along the main river. The bypass is located at an outer river bend, where a separation of bed-load and large wood results due to the secondary currents induced by the river curvature. Large wood floats towards the outer bend due to inertia and the secondary currents whereas bed-load remains at the inner bend. The bypass is separated by a side weir from the main river to ensure that the bed-load remains in the river during bed forming discharges and flood events. New model test are currently carried out at the Laboratory of Hydraulics, Hydrology, and Glaciology (VAW) of ETH Zurich, where sediment continuity should be achieved using an inclined rack. The rack is inclined in flow direction with a degree of 45° to 20°. First results show that the large wood deposits at the upper part of the rack whereas the lower part of the rack remains free for bed-load transport. Furthermore, the backwater rise for the inclined rack due to the accumulated wood is considerably reduced compared to a vertical rack, as a large part of the rack remains clear for the flow to pass. The findings of this studies help to understand the complex interaction between sediment and large wood at a check dam retention structure. Furthermore, new retention structures and rack designs are available, where sediment continuity can partially be maintained to reduce downstream bed erosion.
Luders, Eileen; Toga, Arthur W; Thompson, Paul M
2014-01-01
Numerous studies have demonstrated a sexual dimorphism of the human corpus callosum. However, the question remains if sex differences in brain size, which typically is larger in men than in women, or biological sex per se account for the apparent sex differences in callosal morphology. Comparing callosal dimensions between men and women matched for overall brain size may clarify the true contribution of biological sex, as any observed group difference should indicate pure sex effects. We thus examined callosal morphology in 24 male and 24 female brains carefully matched for overall size. In addition, we selected 24 extremely large male brains and 24 extremely small female brains to explore if observed sex effects might vary depending on the degree to which male and female groups differed in brain size. Using the individual T1-weighted brain images (n=96), we delineated the corpus callosum at midline and applied a well-validated surface-based mesh-modeling approach to compare callosal thickness at 100 equidistant points between groups determined by brain size and sex. The corpus callosum was always thicker in men than in women. However, this callosal sex difference was strongly determined by the cerebral sex difference overall. That is, the larger the discrepancy in brain size between men and women, the more pronounced the sex difference in callosal thickness, with hardly any callosal differences remaining between brain-size matched men and women. Altogether, these findings suggest that individual differences in brain size account for apparent sex differences in the anatomy of the corpus callosum. © 2013.
Luders, Eileen; Toga, Arthur W.; Thompson, Paul M.
2013-01-01
Numerous studies have demonstrated a sexual dimorphism of the human corpus callosum. However, the question remains if sex differences in brain size, which typically is larger in men than in women, or biological sex per se account for the apparent sex differences in callosal morphology. Comparing callosal dimensions between men and women matched for overall brain size may clarify the true contribution of biological sex, as any observed group difference should indicate pure sex effects. We thus examined callosal morphology in 24 male and 24 female brains carefully matched for overall size. In addition, we selected 24 extremely large male brains and 24 extremely small female brains to explore if observed sex effects might vary depending on the degree to which male and female groups differed in brain size. Using the individual T1-weighted brain images (n=96), we delineated the corpus callosum at midline and applied a well-validated surface-based mesh-modeling approach to compare callosal thickness at 100 equidistant points between groups determined by brain size and sex. The corpus callosum was always thicker in men than in women. However, this callosal sex difference was strongly determined by the cerebral sex difference overall. That is, the larger the discrepancy in brain size between men and women, the more pronounced the sex difference in callosal thickness, with hardly any callosal differences remaining between brain-size matched men and women. Altogether, these findings suggest that individual differences in brain size account for apparent sex differences in the anatomy of the corpus callosum. PMID:24064068
The sand bag model of the dispersion of the cosmic body in the atmosphere
NASA Technical Reports Server (NTRS)
Teterev, A. V.; Nemchinov, I. V.
1993-01-01
The strength of the extraterrestrial bodies depends on their structure, composition, dimensions, and the history of this body. The fragmentation of the body due to aerodynamic stresses begins at sufficiently large heights above the surface of the Earth. The process of fragmentation and dispersion of the fragments usually is studied by the hydrodynamic or even gasdynamic models. If the fragmentation process begins due to the initial cracks and faults of the body, or this body consists of large boulders glued by ice, the strength of these boulders after fragmentation remains higher than the aerodynamic stresses exerted at the remaining part of the body. It is supposed that fragmentation occurs at initial moment t = 0 at some height z(sub o) above the surface of the air, these fragments remain solid. The possibility of further fragmentation during the remaining part of the trajectory is not taken into account. If the number of these parts is large enough and their size is small in comparison to the initial radius of the body than we can use the sand bag model proposed in qualitative form.
Individual differences in personality predict how people look at faces.
Perlman, Susan B; Morris, James P; Vander Wyk, Brent C; Green, Steven R; Doyle, Jaime L; Pelphrey, Kevin A
2009-06-22
Determining the ways in which personality traits interact with contextual determinants to shape social behavior remains an important area of empirical investigation. The specific personality trait of neuroticism has been related to characteristic negative emotionality and associated with heightened attention to negative, emotionally arousing environmental signals. However, the mechanisms by which this personality trait may shape social behavior remain largely unspecified. We employed eye tracking to investigate the relationship between characteristics of visual scanpaths in response to emotional facial expressions and individual differences in personality. We discovered that the amount of time spent looking at the eyes of fearful faces was positively related to neuroticism. This finding is discussed in relation to previous behavioral research relating personality to selective attention for trait-congruent emotional information, neuroimaging studies relating differences in personality to amygdala reactivity to socially relevant stimuli, and genetic studies suggesting linkages between the serotonin transporter gene and neuroticism. We conclude that personality may be related to interpersonal interaction by shaping aspects of social cognition as basic as eye contact. In this way, eye gaze represents a possible behavioral link in a complex relationship between genes, brain function, and personality.
Is parasite pressure a driver of chemical cue diversity in ants?
Martin, Stephen J.; Helanterä, Heikki; Drijfhout, Falko P.
2011-01-01
Parasites and pathogens are possibly key evolutionary forces driving recognition systems. However, empirical evidence remains sparse. The ubiquitous pioneering ant Formica fusca is exploited by numerous socially parasitic ant species. We compared the chemical cue diversity, egg and nest mate recognition abilities in two Finnish and two UK populations where parasite pressure is high or absent, respectively. Finnish populations had excellent egg and nest mate discrimination abilities, which were lost in the UK populations. The loss of discrimination behaviour correlates with a loss in key recognition compounds (C25-dimethylalkanes). This was not owing to genetic drift or different ecotypes since neutral gene diversity was the same in both countries. Furthermore, it is known that the cuticular hydrocarbon profiles of non-host ant species remain stable between Finland and the UK. The most parsimonious explanation for the striking difference in the cue diversity (number of C25-dimethylalkanes isomers) between the UK and Finland populations is the large differences in parasite pressure experienced by F. fusca in the two countries. These results have strong parallels with bird (cuckoo) studies and support the hypothesis that parasites are driving recognition cue diversity. PMID:20610426
Kreitz, Carina; Furley, Philip; Memmert, Daniel; Simons, Daniel J
2016-04-01
The probability of inattentional blindness, the failure to notice an unexpected object when attention is engaged on some primary task, is influenced by contextual factors like task demands, features of the unexpected object, and the observer's attention set. However, predicting who will notice an unexpected object and who will remain inattentionally blind has proven difficult, and the evidence that individual differences in cognition affect noticing remains ambiguous. We hypothesized that greater working memory capacity might modulate the effect of attention sets on noticing because working memory is associated with the ability to focus attention selectively. People with greater working memory capacity might be better able to attend selectively to target items, thereby increasing the chances of noticing unexpected objects that were similar to the attended items while decreasing the odds of noticing unexpected objects that differed from the attended items. Our study (N = 120 participants) replicated evidence that task-induced attention sets modulate noticing but found no link between noticing and working memory capacity. Our results are largely consistent with the idea that individual differences in working memory capacity do not predict noticing of unexpected objects in an inattentional blindness task. © The Author(s) 2015.
Structure-Activity Analysis of Biased Agonism at the Human Adenosine A3 Receptor
Baltos, Jo-Anne; Paoletta, Silvia; Nguyen, Anh T. N.; Gregory, Karen J.; Tosh, Dilip K.; Christopoulos, Arthur; Jacobson, Kenneth A.
2016-01-01
Biased agonism at G protein–coupled receptors (GPCRs) has significant implications for current drug discovery, but molecular determinants that govern ligand bias remain largely unknown. The adenosine A3 GPCR (A3AR) is a potential therapeutic target for various conditions, including cancer, inflammation, and ischemia, but for which biased agonism remains largely unexplored. We now report the generation of bias “fingerprints” for prototypical ribose containing A3AR agonists and rigidified (N)-methanocarba 5′-N-methyluronamide nucleoside derivatives with regard to their ability to mediate different signaling pathways. Relative to the reference prototypical agonist IB-MECA, (N)-methanocarba 5′-N-methyluronamide nucleoside derivatives with significant N6 or C2 modifications, including elongated aryl-ethynyl groups, exhibited biased agonism. Significant positive correlation was observed between the C2 substituent length (in Å) and bias toward cell survival. Molecular modeling suggests that extended C2 substituents on (N)-methanocarba 5′-N-methyluronamide nucleosides promote a progressive outward shift of the A3AR transmembrane domain 2, which may contribute to the subset of A3AR conformations stabilized on biased agonist binding. PMID:27136943
Carnacina, Iacopo; Larrarte, Frédérique; Leonardi, Nicoletta
2017-04-01
The performance of sewer networks has important consequences from an environmental and social point of view. Poor functioning can result in flood risk and pollution at a large scale. Sediment deposits forming in sewer trunks might severely compromise the sewer line by affecting the flow field, reducing cross-sectional areas, and increasing roughness coefficients. In spite of numerous efforts, the morphological features of these depositional environments remain poorly understood. The interface between water and sediment remains inefficiently identified and the estimation of the stock of deposit is frequently inaccurate. In part, this is due to technical issues connected to difficulties in collecting accurate field measurements without disrupting existing morphologies. In this paper, results from an extensive field campaign are presented; during the campaign a new survey methodology based on acoustic techniques has been tested. Furthermore, a new algorithm for the detection of the soil-water interface, and therefore for the correct esteem of sediment stocks is proposed. Finally, results in regard to bed topography, and morphological features at two different field sites are presented and reveal that a large variability in bed forms is present along sewer networks. Copyright © 2017 Elsevier Ltd. All rights reserved.
Solomon-Lane, Tessa K.; Pradhan, Devaleena S.; Willis, Madelyne C.; Grober, Matthew S.
2015-01-01
While individual variation in social behaviour is ubiquitous and causes social groups to differ in structure, how these structural differences affect fitness remains largely unknown. We used social network analysis of replicate bluebanded goby (Lythrypnus dalli) harems to identify the reproductive correlates of social network structure. In stable groups, we quantified agonistic behaviour, reproduction and steroid hormones, which can both affect and respond to social/reproductive cues. We identified distinct, optimal social structures associated with different reproductive measures. Male hatching success (HS) was negatively associated with agonistic reciprocity, a network structure that describes whether subordinates ‘reciprocated’ agonism received from dominants. Egg laying was associated with the individual network positions of the male and dominant female. Thus, males face a trade-off between promoting structures that facilitate egg laying versus HS. Whether this reproductive conflict is avoidable remains to be determined. We also identified different social and/or reproductive roles for 11-ketotestosterone, 17β-oestradiol and cortisol, suggesting that specific neuroendocrine mechanisms may underlie connections between network structure and fitness. This is one of the first investigations of the reproductive and neuroendocrine correlates of social behaviour and network structure in replicate, naturalistic social groups and supports network structure as an important target for natural selection. PMID:26156769
The future of fish passage science, engineering, and practice
Silva, Ana T.; Lucas, Martyn C.; Castro-Santos, Theodore R.; Katopodis, Christos; Baumgartner, Lee J.; Thiem, Jason D.; Aarestrup, Kim; Pompeu, Paulo S.; O'Brien, Gordon C.; Braun, Douglas C.; Burnett, Nicholas J.; Zhu, David Z.; Fjeldstad, Hans-Petter; Forseth, Torbjorn; Rajarathnam, Nallamuthu; Williams, John G.; Cooke, Steven J.
2018-01-01
Much effort has been devoted to developing, constructing and refining fish passage facilities to enable target species to pass barriers on fluvial systems, and yet, fishway science, engineering and practice remain imperfect. In this review, 17 experts from different fish passage research fields (i.e., biology, ecology, physiology, ecohydraulics, engineering) and from different continents (i.e., North and South America, Europe, Africa, Australia) identified knowledge gaps and provided a roadmap for research priorities and technical developments. Once dominated by an engineering‐focused approach, fishway science today involves a wide range of disciplines from fish behaviour to socioeconomics to complex modelling of passage prioritization options in river networks. River barrier impacts on fish migration and dispersal are currently better understood than historically, but basic ecological knowledge underpinning the need for effective fish passage in many regions of the world, including in biodiversity hotspots (e.g., equatorial Africa, South‐East Asia), remains largely unknown. Designing efficient fishways, with minimal passage delay and post‐passage impacts, requires adaptive management and continued innovation. While the use of fishways in river restoration demands a transition towards fish passage at the community scale, advances in selective fishways are also needed to manage invasive fish colonization. Because of the erroneous view in some literature and communities of practice that fish passage is largely a proven technology, improved international collaboration, information sharing, method standardization and multidisciplinary training are needed. Further development of regional expertise is needed in South America, Asia and Africa where hydropower dams are currently being planned and constructed.
Couvillon, Margaret J; Fitzpatrick, Ginny; Dornhaus, Anna
Bumble bees are important pollinators of crops and other plants. However, many aspects of their basic biology remain relatively unexplored. For example, one important and unusual natural history feature in bumble bees is the massive size variation seen between workers of the same nest. This size polymorphism may be an adaptation for division of labor, colony economics, or be nonadaptive. It was also suggested that perhaps this variation allows for niche specialization in workers foraging at different temperatures: larger bees might be better suited to forage at cooler temperatures and smaller bees might be better suited to forage at warmer temperatures. This we tested here using a large, enclosed growth chamber, where we were able to regulate the ambient temperature. We found no significant effect of ambient or nest temperature on the average size of bees flying to and foraging from a suspended feeder. Instead, bees of all sizes successfully flew and foraged between 16°C and 36°C. Thus, large bees foraged even at very hot temperatures, which we thought might cause overheating. Size variation therefore could not be explained in terms of niche specialization for foragers at different temperatures.
NASA Technical Reports Server (NTRS)
Fields, J. M.
1984-01-01
Even though there are surveys in which annoyance decreases as the number of events increases above about 150 a day, the available evidence is not considered strong enough to reject the conventional assumption that reactions are related to the logarithm of the number of events. The data do not make it possible to reject the conventional assumption that the effects of the number of events and the peak noise level are additive. It is found that even when equivalent questionnaire items and definitions of noise events could be used, differences between the surveys' estimates of the effect of the number of events remained large. Three explanations are suggested for inconsistent estimates. The first has to do with errors in specifying the values of noise parameters, the second with the effects of unmeasured acoustical and area characteristics that are correlated with noise level or number, and the third with large sampling errors deriving from community differences in response to noise. It is concluded that significant advances in the knowledge about the effects of the number of noise events can be made only if surveys include large numbers of study areas.
Mishra, U.; Jastrow, J.D.; Matamala, R.; Hugelius, G.; Koven, C.D.; Harden, Jennifer W.; Ping, S.L.; Michaelson, G.J.; Fan, Z.; Miller, R.M.; McGuire, A.D.; Tarnocai, C.; Kuhry, P.; Riley, W.J.; Schaefer, K.; Schuur, E.A.G.; Jorgenson, M.T.; Hinzman, L.D.
2013-01-01
The vast amount of organic carbon (OC) stored in soils of the northern circumpolar permafrost region is a potentially vulnerable component of the global carbon cycle. However, estimates of the quantity, decomposability, and combustibility of OC contained in permafrost-region soils remain highly uncertain, thereby limiting our ability to predict the release of greenhouse gases due to permafrost thawing. Substantial differences exist between empirical and modeling estimates of the quantity and distribution of permafrost-region soil OC, which contribute to large uncertainties in predictions of carbon–climate feedbacks under future warming. Here, we identify research challenges that constrain current assessments of the distribution and potential decomposability of soil OC stocks in the northern permafrost region and suggest priorities for future empirical and modeling studies to address these challenges.
Nature of peptide wrapping onto metal nanoparticle catalysts and driving forces for size control.
Ramezani-Dakhel, Hadi; Bedford, Nicholas M; Woehl, Taylor J; Knecht, Marc R; Naik, Rajesh R; Heinz, Hendrik
2017-06-22
Colloidal metal nanocrystals find many applications in catalysis, energy conversion devices, and therapeutics. However, the nature of ligand interactions and implications on shape control have remained uncertain at the atomic scale. Large differences in peptide adsorption strength and facet specificity were found on flat palladium surfaces versus surfaces of nanoparticles of 2 to 3 nm size using accurate atomistic simulations with the Interface force field. Folding of longer peptides across many facets explains the formation of near-spherical particles with local surface disorder, in contrast to the possibility of nanostructures of higher symmetry with shorter ligands. The average particle size in TEM correlates inversely with the surface coverage with a given ligand and with the strength of ligand adsorption. The role of specific amino acids and sequence mutations on the nanoparticle size and facet composition is discussed, as well as the origin of local surface disorder that leads to large differences in catalytic reactivity.
Online personal ads: community and sex, virtually.
Gudelunas, David
2005-01-01
This study samples 200 personal advertisements from the online gay and lesbian global Web portal PlanetOut. This data, along with survey responses completed by advertisers included in the sample, are used to frame a discussion on the use of online gay and lesbian spaces and communities. Despite interacting in a global space, data showed that advertisers remained aware of their local identities. Differences between advertisers were most notable between gender and whether they logged on in a small or large town. Advertisers were interested in interacting locally, eager to move from online to offline communication, often-times not overly concerned with maintaining anonymity, and not interested in toying with multiple identities. Users of PlanetOut personals largely did not consider themselves part of a virtual gay and lesbian community even when they recognized the existence of a local geographically-based gay and lesbian community. However, the dynamic nature of online personal advertisements did allow for a new type of interactive advertisement that does differ from previous print forums.
Approximate registration of point clouds with large scale differences
NASA Astrophysics Data System (ADS)
Novak, D.; Schindler, K.
2013-10-01
3D reconstruction of objects is a basic task in many fields, including surveying, engineering, entertainment and cultural heritage. The task is nowadays often accomplished with a laser scanner, which produces dense point clouds, but lacks accurate colour information, and lacks per-point accuracy measures. An obvious solution is to combine laser scanning with photogrammetric recording. In that context, the problem arises to register the two datasets, which feature large scale, translation and rotation differences. The absence of approximate registration parameters (3D translation, 3D rotation and scale) precludes the use of fine-registration methods such as ICP. Here, we present a method to register realistic photogrammetric and laser point clouds in a fully automated fashion. The proposed method decomposes the registration into a sequence of simpler steps: first, two rotation angles are determined by finding dominant surface normal directions, then the remaining parameters are found with RANSAC followed by ICP and scale refinement. These two steps are carried out at low resolution, before computing a precise final registration at higher resolution.
Inexplicable or Simply Unexplained? The Management of Maize Seed in Mexico
Dyer, George A.; López-Feldman, Alejandro
2013-01-01
Farmer management of plant germplasm pre-dates crop domestication, but humans’ role in crop evolution and diversity remains largely undocumented and often contested. Seemingly inexplicable practices observed throughout agricultural history, such as exchanging or replacing seed, continue to structure crop populations across the developing world. Seed management practices can be construed as events in the life history of crops and management data used to model crop demography, but this requires suitable quantitative data. As a prerequisite to addressing the causes and implications of maize seed management, we describe its patterns of variation across Mexico by drawing from the literature and new analysis. We find that rates of seed replacement, introduction and diffusion differ significantly across regions and altitudinal zones, but interactions among explanatory factors can obscure patterns of variation. The type, source, geographic origin and ownership of seed help explain observed rates. Yet, controlling for the characteristics of germplasm barely reduces interregional differences vastly exceeding variation across elevations. With few exceptions, monotonic altitudinal trends are absent. Causal relationships between management practices and the physical environment could determine farmers’ wellbeing and crop conservation in the face of climate change. Scarce and inconsistent data on management nevertheless could prevent an understanding of these relationships. Current conceptions on the management and dynamics of maize diversity are founded on a patchwork of observations in surprisingly few and dissimilar environments. Our estimates of management practices should shed light on differences in maize population dynamics across Mexico. Consistency with previous studies spanning over a decade suggests that common sets of forces are present within large areas, but causal associations remain unknown. The next step in explaining crop diversity should address variation in seed management across space and time simultaneously while identifying farmers’ values and motivations as underlying forces. PMID:23840847
Inexplicable or simply unexplained? The management of maize seed in Mexico.
Dyer, George A; López-Feldman, Alejandro
2013-01-01
Farmer management of plant germplasm pre-dates crop domestication, but humans' role in crop evolution and diversity remains largely undocumented and often contested. Seemingly inexplicable practices observed throughout agricultural history, such as exchanging or replacing seed, continue to structure crop populations across the developing world. Seed management practices can be construed as events in the life history of crops and management data used to model crop demography, but this requires suitable quantitative data. As a prerequisite to addressing the causes and implications of maize seed management, we describe its patterns of variation across Mexico by drawing from the literature and new analysis. We find that rates of seed replacement, introduction and diffusion differ significantly across regions and altitudinal zones, but interactions among explanatory factors can obscure patterns of variation. The type, source, geographic origin and ownership of seed help explain observed rates. Yet, controlling for the characteristics of germplasm barely reduces interregional differences vastly exceeding variation across elevations. With few exceptions, monotonic altitudinal trends are absent. Causal relationships between management practices and the physical environment could determine farmers' wellbeing and crop conservation in the face of climate change. Scarce and inconsistent data on management nevertheless could prevent an understanding of these relationships. Current conceptions on the management and dynamics of maize diversity are founded on a patchwork of observations in surprisingly few and dissimilar environments. Our estimates of management practices should shed light on differences in maize population dynamics across Mexico. Consistency with previous studies spanning over a decade suggests that common sets of forces are present within large areas, but causal associations remain unknown. The next step in explaining crop diversity should address variation in seed management across space and time simultaneously while identifying farmers' values and motivations as underlying forces.
Cai, Andong; Liang, Guopeng; Zhang, Xubo; Zhang, Wenju; Li, Ling; Rui, Yichao; Xu, Minggang; Luo, Yiqi
2018-05-01
Understanding drivers of straw decomposition is essential for adopting appropriate management practice to improve soil fertility and promote carbon (C) sequestration in agricultural systems. However, predicting straw decomposition and characteristics is difficult because of the interactions between many factors related to straw properties, soil properties, and climate, especially under future climate change conditions. This study investigated the driving factors of straw decomposition of six types of crop straw including wheat, maize, rice, soybean, rape, and other straw by synthesizing 1642 paired data from 98 published papers at spatial and temporal scales across China. All the data derived from the field experiments using little bags over twelve years. Overall, despite large differences in climatic and soil properties, the remaining straw carbon (C, %) could be accurately represented by a three-exponent equation with thermal time (accumulative temperature). The lignin/nitrogen and lignin/phosphorus ratios of straw can be used to define the size of labile, intermediate, and recalcitrant C pool. The remaining C for an individual type of straw in the mild-temperature zone was higher than that in the warm-temperature and subtropical zone within one calendar year. The remaining straw C after one thermal year was 40.28%, 37.97%, 37.77%, 34.71%, 30.87%, and 27.99% for rice, soybean, rape, wheat, maize, and other straw, respectively. Soil available nitrogen and phosphorus influenced the remaining straw C at different decomposition stages. For one calendar year, the total amount of remaining straw C was estimated to be 29.41 Tg and future temperature increase of 2 °C could reduce the remaining straw C by 1.78 Tg. These findings confirmed the long-term straw decomposition could be mainly driven by temperature and straw quality, and quantitatively predicted by thermal time with the three-exponent equation for a wide array of straw types at spatial and temporal scales in agro-ecosystems of China. Copyright © 2018 Elsevier B.V. All rights reserved.
Leaf δ18O of remaining trees is affected by thinning intensity in a semiarid pine forest.
Moreno-Gutiérrez, Cristina; Barberá, Gonzalo G; Nicolás, Emilio; DE Luis, Martín; Castillo, Víctor M; Martínez-Fernández, Faustino; Querejeta, José I
2011-06-01
Silvicultural thinning usually improves the water status of remaining trees in water-limited forests. We evaluated the usefulness of a dual stable isotope approach (δ¹³C, δ¹⁸O) for comparing the physiological performance of remaining trees between forest stands subjected to two different thinning intensities (moderate versus heavy) in a 60-year-old Pinus halepensis Mill. plantation in semiarid southeastern Spain. We measured bulk leaf δ¹³C and δ¹⁸O, foliar elemental concentrations, stem water content, stem water δ¹⁸O (δ¹⁸O(stem water)), tree ring widths and leaf gas exchange rates to assess the influence of forest stand density on tree performance. Remaining trees in low-density stands (heavily thinned) showed lower leaf δ¹⁸O, and higher stomatal conductance (g(s)), photosynthetic rate and radial growth than those in moderate-density stands (moderately thinned). By contrast, leaf δ¹³C, intrinsic water-use efficiency, foliar elemental concentrations and δ¹⁸O(stem water) were unaffected by stand density. Lower foliar δ¹⁸O in heavily thinned stands reflected higher g(s) of remaining trees due to decreased inter-tree competition for water, whereas higher photosynthetic rate was largely attributable to reduced stomatal limitation to CO₂ uptake. The dual isotope approach provided insight into the early (12 months) effects of stand density manipulation on the physiological performance of remaining trees. © 2011 Blackwell Publishing Ltd.
Bengston, Sarah E; Dahan, Romain A; Donaldson, Zoe; Phelps, Steven M; van Oers, Kees; Sih, Andrew; Bell, Alison M
2018-06-01
Behaviour is a key interface between an animal's genome and its environment. Repeatable individual differences in behaviour have been extensively documented in animals, but the molecular underpinnings of behavioural variation among individuals within natural populations remain largely unknown. Here, we offer a critical review of when molecular techniques may yield new insights, and we provide specific guidance on how and whether the latest tools available are appropriate given different resources, system and organismal constraints, and experimental designs. Integrating molecular genetic techniques with other strategies to study the proximal causes of behaviour provides opportunities to expand rapidly into new avenues of exploration. Such endeavours will enable us to better understand how repeatable individual differences in behaviour have evolved, how they are expressed and how they can be maintained within natural populations of animals.
Convection in the Rayleigh-Bénard flow with all fluid properties variable
NASA Astrophysics Data System (ADS)
Sassos, Athanasios; Pantokratoras, Asterios
2011-10-01
In the present paper, the effect of variable fluid properties (density, viscosity, thermal conductivity and specific heat) on the convection in the classical Rayleigh-Bénard problem is investigated. The investigation concerns water, air, and engine oil by taking into account the variation of fluid properties with temperature. The results are obtained by numerically solving the governing equations, using the SIMPLE algorithm and covering large temperature differences. It is found that the critical Rayleigh number increases as the temperature difference increases considering all fluid properties variable. However, when the fluid properties are kept constant, calculated at the mean temperature, and only density is considered variable, the critical Rayleigh number either decreases or remains constant.
Habitat fragmentation influences nestling growth in Mediterranean blue and great tits
NASA Astrophysics Data System (ADS)
Bueno-Enciso, Javier; Ferrer, Esperanza S.; Barrientos, Rafael; Serrano-Davies, Eva; Sanz, Juan José
2016-01-01
In patchy forest areas, the size of the forest patch where birds breed has a strong influence on their breeding success. However, the proximate effects contributing to lowering the breeding success in small forest patches remain unclear; and a shortage of crucial resources in those forest patches has been suggested to account in some degree for this failure. With the aim to further investigate this issue, we have monitored the breeding cycle of blue and great tits in three 'large' forest patches (ranging between 26.5 and 29.6 ha) and twelve 'small' forest patches (ranging between 1.1 and 2.1 ha) in a Mediterranean area in central Spain, during three years (2011-2013). We also recorded the nestling diet inside the nest-boxes with the aid of handy-cams. Only males significantly differed between forest patch size categories; being on average younger and with better body condition in small patches for great and blue tits respectively. Reproductive traits did not vary between forest patch size categories, but the body condition of blue tit nestlings and the size of great tit nestlings did, being significantly better and larger respectively in large forest patches. The recruitment rate of blue tit nestlings was also higher in large patches. Regarding nestling diet, blue tits did not differ but great tits did, delivering a larger amount of caterpillars in large forest patches. Most variation in the reproductive traits occurred between years, probably due to annual differences in environmental conditions. This study suggests that food supply could be limiting the breeding success of birds above all in small patches, but also in large patches under particular environmental conditions.
Anber, Usama; Gentine, Pierre; Wang, Shuguang; Sobel, Adam H.
2015-01-01
The diurnal and seasonal water cycles in the Amazon remain poorly simulated in general circulation models, exhibiting peak evapotranspiration in the wrong season and rain too early in the day. We show that those biases are not present in cloud-resolving simulations with parameterized large-scale circulation. The difference is attributed to the representation of the morning fog layer, and to more accurate characterization of convection and its coupling with large-scale circulation. The morning fog layer, present in the wet season but absent in the dry season, dramatically increases cloud albedo, which reduces evapotranspiration through its modulation of the surface energy budget. These results highlight the importance of the coupling between the energy and hydrological cycles and the key role of cloud albedo feedback for climates over tropical continents. PMID:26324902
Spatial organization of chromatin domains and compartments in single chromosomes
NASA Astrophysics Data System (ADS)
Wang, Siyuan; Su, Jun-Han; Beliveau, Brian; Bintu, Bogdan; Moffitt, Jeffrey; Wu, Chao-Ting; Zhuang, Xiaowei
The spatial organization of chromatin critically affects genome function. Recent chromosome-conformation-capture studies have revealed topologically associating domains (TADs) as a conserved feature of chromatin organization, but how TADs are spatially organized in individual chromosomes remains unknown. Here, we developed an imaging method for mapping the spatial positions of numerous genomic regions along individual chromosomes and traced the positions of TADs in human interphase autosomes and X chromosomes. We observed that chromosome folding deviates from the ideal fractal-globule model at large length scales and that TADs are largely organized into two compartments spatially arranged in a polarized manner in individual chromosomes. Active and inactive X chromosomes adopt different folding and compartmentalization configurations. These results suggest that the spatial organization of chromatin domains can change in response to regulation.
Krioukov, Dmitri; Kitsak, Maksim; Sinkovits, Robert S; Rideout, David; Meyer, David; Boguñá, Marián
2012-01-01
Prediction and control of the dynamics of complex networks is a central problem in network science. Structural and dynamical similarities of different real networks suggest that some universal laws might accurately describe the dynamics of these networks, albeit the nature and common origin of such laws remain elusive. Here we show that the causal network representing the large-scale structure of spacetime in our accelerating universe is a power-law graph with strong clustering, similar to many complex networks such as the Internet, social, or biological networks. We prove that this structural similarity is a consequence of the asymptotic equivalence between the large-scale growth dynamics of complex networks and causal networks. This equivalence suggests that unexpectedly similar laws govern the dynamics of complex networks and spacetime in the universe, with implications to network science and cosmology.
Krioukov, Dmitri; Kitsak, Maksim; Sinkovits, Robert S.; Rideout, David; Meyer, David; Boguñá, Marián
2012-01-01
Prediction and control of the dynamics of complex networks is a central problem in network science. Structural and dynamical similarities of different real networks suggest that some universal laws might accurately describe the dynamics of these networks, albeit the nature and common origin of such laws remain elusive. Here we show that the causal network representing the large-scale structure of spacetime in our accelerating universe is a power-law graph with strong clustering, similar to many complex networks such as the Internet, social, or biological networks. We prove that this structural similarity is a consequence of the asymptotic equivalence between the large-scale growth dynamics of complex networks and causal networks. This equivalence suggests that unexpectedly similar laws govern the dynamics of complex networks and spacetime in the universe, with implications to network science and cosmology. PMID:23162688
Anber, Usama; Gentine, Pierre; Wang, Shuguang; ...
2015-08-31
The diurnal and seasonal water cycles in the Amazon remain poorly simulated in general circulation models, exhibiting peak evapotranspiration in the wrong season and rain too early in the day. We show that those biases are not present in cloud-resolving simulations with parameterized large-scale circulation. The difference is attributed to the representation of the morning fog layer, and to more accurate characterization of convection and its coupling with large-scale circulation. The morning fog layer, present in the wet season but absent in the dry season, dramatically increases cloud albedo, which reduces evapotranspiration through its modulation of the surface energy budget.more » Finally, these results highlight the importance of the coupling between the energy and hydrological cycles and the key role of cloud albedo feedback for climates over tropical continents.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Anber, Usama; Gentine, Pierre; Wang, Shuguang
The diurnal and seasonal water cycles in the Amazon remain poorly simulated in general circulation models, exhibiting peak evapotranspiration in the wrong season and rain too early in the day. We show that those biases are not present in cloud-resolving simulations with parameterized large-scale circulation. The difference is attributed to the representation of the morning fog layer, and to more accurate characterization of convection and its coupling with large-scale circulation. The morning fog layer, present in the wet season but absent in the dry season, dramatically increases cloud albedo, which reduces evapotranspiration through its modulation of the surface energy budget.more » Finally, these results highlight the importance of the coupling between the energy and hydrological cycles and the key role of cloud albedo feedback for climates over tropical continents.« less
NASA Astrophysics Data System (ADS)
Dey, Joyoni; Segars, W. Paul; Pretorius, P. Hendrik; King, Michael A.
2015-08-01
Purpose: We investigate the differences without/with respiratory motion correction in apparent imaging agent localization induced in reconstructed emission images when the attenuation maps used for attenuation correction (from CT) are misaligned with the patient anatomy during emission imaging due to differences in respiratory state. Methods: We investigated use of attenuation maps acquired at different states of a 2 cm amplitude respiratory cycle (at end-expiration, at end-inspiration, the center map, the average transmission map, and a large breath-hold beyond range of respiration during emission imaging) to correct for attenuation in MLEM reconstruction for several anatomical variants of the NCAT phantom which included both with and without non-rigid motion between heart and sub-diaphragmatic regions (such as liver, kidneys etc). We tested these cases with and without emission motion correction and attenuation map alignment/non-alignment. Results: For the NCAT default male anatomy the false count-reduction due to breathing was largely removed upon emission motion correction for the large majority of the cases. Exceptions (for the default male) were for the cases when using the large-breathhold end-inspiration map (TI_EXT), when we used the end-expiration (TE) map, and to a smaller extent, the end-inspiration map (TI). However moving the attenuation maps rigidly to align the heart region, reduced the remaining count-reduction artifacts. For the female patient count-reduction remained post motion correction using rigid map-alignment due to the breast soft-tissue misalignment. Quantitatively, after the transmission (rigid) alignment correction, the polar-map 17-segment RMS error with respect to the reference (motion-less case) reduced by 46.5% on average for the extreme breathhold case. The reductions were 40.8% for end-expiration map and 31.9% for end-inspiration cases on the average, comparable to the semi-ideal case where each state uses its own attenuation map for correction. Conclusions: Two main conclusions are that even rigid emission motion correction to rigidly align the heart region to the attenuation map helps in average cases to reduce the count-reduction artifacts and secondly, within the limits of the study (ex. rigid correction) when there is lung tissue inferior to the heart as with the NCAT phantom employed in this study end-expiration maps (TE) might best be avoided as they may create more artifacts than the end-inspiration (TI) maps.
Genetic variation in insulin-induced kinase signaling
Wang, Isabel Xiaorong; Ramrattan, Girish; Cheung, Vivian G
2015-01-01
Individual differences in sensitivity to insulin contribute to disease susceptibility including diabetes and metabolic syndrome. Cellular responses to insulin are well studied. However, which steps in these response pathways differ across individuals remains largely unknown. Such knowledge is needed to guide more precise therapeutic interventions. Here, we studied insulin response and found extensive individual variation in the activation of key signaling factors, including ERK whose induction differs by more than 20-fold among our subjects. This variation in kinase activity is propagated to differences in downstream gene expression response to insulin. By genetic analysis, we identified cis-acting DNA variants that influence signaling response, which in turn affects downstream changes in gene expression and cellular phenotypes, such as protein translation and cell proliferation. These findings show that polymorphic differences in signal transduction contribute to individual variation in insulin response, and suggest kinase modulators as promising therapeutics for diseases characterized by insulin resistance. PMID:26202599
DOE Office of Scientific and Technical Information (OSTI.GOV)
Endele, Max; Etzrodt, Martin; Schroeder, Timm, E-mail: timm.schroeder@bsse.ethz.ch
Hematopoiesis is the cumulative consequence of finely tuned signaling pathways activated through extrinsic factors, such as local niche signals and systemic hematopoietic cytokines. Whether extrinsic factors actively instruct the lineage choice of hematopoietic stem and progenitor cells or are only selectively allowing survival and proliferation of already intrinsically lineage-committed cells has been debated over decades. Recent results demonstrated that cytokines can instruct lineage choice. However, the precise function of individual cytokine-triggered signaling molecules in inducing cellular events like proliferation, lineage choice, and differentiation remains largely elusive. Signal transduction pathways activated by different cytokine receptors are highly overlapping, but support themore » production of distinct hematopoietic lineages. Cellular context, signaling dynamics, and the crosstalk of different signaling pathways determine the cellular response of a given extrinsic signal. New tools to manipulate and continuously quantify signaling events at the single cell level are therefore required to thoroughly interrogate how dynamic signaling networks yield a specific cellular response. - Highlights: • Recent studies provided definite proof for lineage-instructive action of cytokines. • Signaling pathways involved in hematopoietic lineage instruction remain elusive. • New tools are emerging to quantitatively study dynamic signaling networks over time.« less
Sustaining Community Participation: What Remains After the Money Ends?
NASA Astrophysics Data System (ADS)
Nkansa, Grace Akukwe; Chapman, David W.
2006-12-01
SUSTAINING COMMUNITY PARTICIPATION: WHAT REMAINS AFTER THE MONEY ENDS? - A major concern confronting development specialists in the education sector is the sustainability of project activities and outcomes, that is, their ability to persist once external funding ends. The increased attention of international development-assistance organizations to sustainability reflects the greater recent focus on outcome-based funding. The present study investigates differences between six communities in Ghana that varied in their ability to sustain externally initiated community-participation activities beyond the life of the external development-assistance project that promoted those activities. It was hypothesized that high- and low-sustaining communities differ in eight managerial and socio-cultural dimensions suggested by earlier research to be important for sustainability of community-level activities: planning, transparency, leadership, and participation, on one hand, and, on the other, social cohesion, resources, community skills, and valuing of education. Findings indicate that leadership and social cohesion are the two most vital elements in the sustainability of organizational structures intended to promote community participation in the oversight of local schools. Other factors suggested by the model are largely subsumed under leadership, so that the model can be simplified.
Action Potential Dynamics in Fine Axons Probed with an Axonally Targeted Optical Voltage Sensor.
Ma, Yihe; Bayguinov, Peter O; Jackson, Meyer B
2017-01-01
The complex and malleable conduction properties of axons determine how action potentials propagate through extensive axonal arbors to reach synaptic terminals. The excitability of axonal membranes plays a major role in neural circuit function, but because most axons are too thin for conventional electrical recording, their properties remain largely unexplored. To overcome this obstacle, we used a genetically encoded hybrid voltage sensor (hVOS) harboring an axonal targeting motif. Expressing this probe in transgenic mice enabled us to monitor voltage changes optically in two populations of axons in hippocampal slices, the large axons of dentate granule cells (mossy fibers) in the stratum lucidum of the CA3 region and the much finer axons of hilar mossy cells in the inner molecular layer of the dentate gyrus. Action potentials propagated with distinct velocities in each type of axon. Repetitive firing broadened action potentials in both populations, but at an intermediate frequency the degree of broadening differed. Repetitive firing also attenuated action potential amplitudes in both mossy cell and granule cell axons. These results indicate that the features of use-dependent action potential broadening, and possible failure, observed previously in large nerve terminals also appear in much finer unmyelinated axons. Subtle differences in the frequency dependences could influence the propagation of activity through different pathways to excite different populations of neurons. The axonally targeted hVOS probe used here opens up the diverse repertoire of neuronal processes to detailed biophysical study.
Pollination of Granadilla (Passiflora ligularis) Benefits From Large Wild Insects.
Gutiérrez-Chacón, Catalina; Fornoff, Felix; Ospina-Torres, Rodulfo; Klein, Alexandra-Maria
2018-05-15
The contribution of wild pollinators to food production has recently been assessed for many crops, although it remains unclear for several tropical crops. Granadilla (Passiflora ligularis Juss), a crop native to the tropical Andes, is one such crop where a gap exists regarding comprehensive knowledge about its pollination system. In a field experiment in the Colombian Andes, we 1) describe flower visitors in terms of visit quantity (visitation rate) and quality (touches of flower-reproductive structures), 2) assess the pollination system by comparing fruit set and fruit weight per flower in three pollination treatments: pollinator exclusion, open pollination, and supplementary pollination, and 3) evaluate pollination deficits (difference between open and supplementary pollination) in relation to pollinator density. We observed 12 bee species visiting granadilla flowers, with Apis mellifera Linnaeus being the most frequent species. However, large bees such as Xylocopa lachnea Moure and Epicharis rustica Olivier touched stigmata and anthers more often. Fruit set and fruit weight per flower were significantly lower in the pollinator exclusion treatment compared to open and supplementary pollination, while the latter treatments showed nonsignificant differences. Pollination deficit significantly decreased with the increasing density of large bees and wasps. Our results illustrate the high dependency of granadilla on wild pollinating insects and highlight the crucial role of large insects to granadilla production. This stresses the need to maintain or increase the density of large pollinators in granadilla production areas, which in turn will necessitate better knowledge on their ecological requirements to inform landscape planning and population-management programs.
The Safety and Efficacy of Irreversible Electroporation for Large Hepatocellular Carcinoma.
Zeng, Jianying; Liu, Guifeng; Li, Zhong-Hai; Yang, Yi; Fang, Gang; Li, Rong-Rong; Xu, Ke-Cheng; Niu, Lizhi
2017-02-01
This study aimed to investigate the safety and effectiveness of irreversible electroporation ablation for unresectable large liver cancer. Fourteen patients were enrolled: 8 with large hepatocellular carcinoma (tumor diameter: 5.1-11.5 cm) and 6 with medium hepatocellular carcinoma (tumor diameter: 3.0-4.1 cm). All patients received percutaneous irreversible electroporation ablation. Ablation time and the incidence of complications were assessed by a t test. Post-irreversible electroporation and regular contrast-enhanced computerized tomography scans were performed to investigate the effect of tumor size (large vs medium) on irreversible electroporation treatment efficacy; 4-table data were assessed using a Fisher exact test. The 14 patients completed irreversible electroporation ablation successfully. In the large hepatocellular carcinoma group, no major complications occurred in the perioperative period. Minor complications comprised bloating, hypokalemia, edema, low white blood cells, and blood clotting abnormalities. All complications were mild and improved after symptomatic treatment. The frequency of minor complications was not significantly different ( P > .05) compared with the medium hepatocellular carcinoma group. The average follow-up time was 2.8 ± 2.1 months and complete ablation was achieved in 25% (2/8; residual = 75%). For the patients with medium hepatocellular carcinoma, the mean follow-up time was 4.3 ± 3.2 months; the rate of complete ablation was 66.6% (4/6; residual rate = 33.3%). The complete ablation rate was not statistically different between the 2 groups ( P > .05). Irreversible electroporation ablation for unresectable large hepatocellular carcinoma is safe, with no major complications. Short-term efficacy is relatively good; however, long-term efficacy remains to be explored.
NASA Astrophysics Data System (ADS)
Yan, Qing; Zhang, Zhongshi; Wang, Huijun
2018-03-01
To understand the behaviors of tropical cyclones (TCs), it is very important to explore how TCs respond to anthropogenic greenhouse gases and natural forcings. Volcanic eruptions are a major natural forcing mechanism because they inject sulphate aerosols into the stratosphere, which modulate the global climate by absorbing and scattering solar radiation. The number of Atlantic hurricanes is thought to be reduced following strong tropical eruptions, but whether the response of TCs varies with the locations of the volcanoes and the different ocean basins remains unknown. Here, we use the Community Earth System Model-Last Millennium Ensemble to investigate the response of the large-scale environmental factors that spawn TCs to strong volcanic eruptions at different latitudes. A composite analysis indicates that tropical and northern hemisphere volcanic eruptions lead to significantly unfavorable conditions for TC genesis over the whole Pacific basin and the North Atlantic during the 3 years post-eruption, relative to the preceding 3 years. Southern hemisphere volcanic eruptions result in obviously unfavorable conditions for TC formation over the southwestern Pacific, but more favorable conditions over the North Atlantic. The mean response over the Indian Ocean is generally muted and insignificant. It should be noted that volcanic eruptions impact on environmental conditions through both the direct effect (i.e. on radiative forcing) and the indirect effect (i.e. on El Niño-Southern Oscillation), which is not differentiated in this study. In addition, the spread of the TC genesis response is considerably large for each category of eruptions over each ocean basin, which is also seen in the observational/proxy-based records. This large spread is attributed to the differences in stratospheric aerosol distributions, initial states and eruption intensities, and makes the short-term forecast of TC activity following the next large eruption challenging.
The North American contribution to our knowledge of childhood tuberculosis and its epidemiology.
Donald, P R
2014-08-01
Although it comprises a substantial proportion of the tuberculosis (TB) burden, particularly in developing communities, childhood TB was until recently largely neglected. North American researchers and clinicians have made substantial contributions to our knowledge of TB in children; their findings, gathered mostly before the availability of chemotherapy, remain an irreplaceable source of learning for modern practice, decision making and TB control, and pose questions regarding TB pathophysiology that remain unanswered. By the time chemotherapy was introduced, it was known that very young children were extremely susceptible to serious disease and that adolescence was a period when there was a transition in the underlying natural response to infection to one characterised by necrotising lung lesions associated with sputum microscopy smear positivity. Researchers such as Miriam Brailey, Edith Lincoln and Jay Arthur Myers carried out studies, over three decades in some cases, documenting likely consequences of tuberculous infection in childhood at different ages and under different circumstances. Infected children aged <3 years remain candidates for the urgent institution of chemoprophylaxis and the search for close household contacts. In high-income communities with low TB incidence, a tuberculin-positive child remains an important index for the presence of infectious adults. Wade Hampton Frost drew attention to the age-related epidemiology of TB, identifying it as a most important feature of our understanding of TB pathophysiology; more than 70 years after his death, we still do not understand why there is a change in the nature of TB during adolescence that makes expectoration of infectious sputum possible.
Deighton, Jessica; Humphrey, Neil; Belsky, Jay; Boehnke, Jan; Vostanis, Panos; Patalay, Praveetha
2018-03-01
There is a growing appreciation that child functioning in different domains, levels, or systems are interrelated over time. Here, we investigate links between internalizing symptoms, externalizing problems, and academic attainment during middle childhood and early adolescence, drawing on two large data sets (child: mean age 8.7 at enrolment, n = 5,878; adolescent: mean age 11.7, n = 6,388). Using a 2-year cross-lag design, we test three hypotheses - adjustment erosion, academic incompetence, and shared risk - while also examining the moderating influence of gender. Multilevel structural equation models provided consistent evidence of the deleterious effect of externalizing problems on later academic achievement in both cohorts, supporting the adjustment-erosion hypothesis. Evidence supporting the academic-incompetence hypothesis was restricted to the middle childhood cohort, revealing links between early academic failure and later internalizing symptoms. In both cohorts, inclusion of shared-risk variables improved model fit and rendered some previously established cross-lag pathways non-significant. Implications of these findings are discussed, and study strengths and limitations noted. Statement of contribution What is already known on this subject? Longitudinal research and in particular developmental cascades literature make the case for weaker associations between internalizing symptoms and academic performance than between externalizing problems and academic performance. Findings vary in terms of the magnitude and inferred direction of effects. Inconsistencies may be explained by different age ranges, prevalence of small-to-modest sample sizes, and large time lags between measurement points. Gender differences remain underexamined. What does this study add? The present study used cross-lagged models to examine longitudinal associations in age groups (middle child and adolescence) in a large-scale British sample. The large sample size not only allows for improvements on previous measurement models (e.g., allowing the analysis to account for nesting, and estimation of latent variables) but also allows for examination of gender differences. The findings clarify the role of shared-risk factors in accounting for associations between internalizing, externalizing, and academic performance, by demonstrating that shared-risk factors do not fully account for relationships between internalizing, externalizing, and academic achievement. Specifically, some pathways between mental health and academic attainment consistently remain, even after shared-risk variables have been accounted for. Findings also present consistent support for the potential impact of behavioural problems on children's academic attainment. The negative relationship between low academic attainment and subsequent internalizing symptoms for younger children is also noteworthy. © 2017 The British Psychological Society.
NASA Astrophysics Data System (ADS)
Auler, Augusto S.; Wang, Xianfeng; Edwards, R. Lawrence; Cheng, Hai; Cristalli, Patrícia S.; Smart, Peter L.; Richards, David A.
2004-10-01
Several geomorphic features and palaeobiotic remains in now semi-arid northeastern Brazil indicate major palaeoenvironmental changes during past periods of increased rainfall. 230Th mass spectrometric ages of speleothems and travertines have allowed the determination of the timing and duration of wetter than present conditions. The data demonstrate that wet events have occurred throughout much of the Pleistocene, present dry conditions having been established at the end of the Younger Dryas. A markedly different fauna comprising megafaunal elements not adapted to the present low arboreal scrubland caatinga vegetation existed in the area. Palaeobotanical remains embedded in travertine indicate forested vegetation at these wetter intervals, suggesting that the caatinga was then replaced or mixed with a semi-deciduous forest. Due to the abundance of travertine sites containing fossil botanical remains in northeastern Brazil, it is believed that forest expansion occurred over large areas of the now semi-arid zone, showing that the long hypothesised forested links between biodiversity-rich Amazon and Atlantic rainforests may indeed have existed during these moister phases. Copyright
Melo, Mariane B; Nguyen, Quynh P; Cordeiro, Cynthia; Hassan, Musa A; Yang, Ninghan; McKell, Renée; Rosowski, Emily E; Julien, Lindsay; Butty, Vincent; Dardé, Marie-Laure; Ajzenberg, Daniel; Fitzgerald, Katherine; Young, Lucy H; Saeij, Jeroen P J
2013-01-01
Most isolates of Toxoplasma from Europe and North America fall into one of three genetically distinct clonal lineages, the type I, II and III lineages. However, in South America these strains are rarely isolated and instead a great variety of other strains are found. T. gondii strains differ widely in a number of phenotypes in mice, such as virulence, persistence, oral infectivity, migratory capacity, induction of cytokine expression and modulation of host gene expression. The outcome of toxoplasmosis in patients is also variable and we hypothesize that, besides host and environmental factors, the genotype of the parasite strain plays a major role. The molecular basis for these differences in pathogenesis, especially in strains other than the clonal lineages, remains largely unexplored. Macrophages play an essential role in the early immune response against T. gondii and are also the cell type preferentially infected in vivo. To determine if non-canonical Toxoplasma strains have unique interactions with the host cell, we infected murine macrophages with 29 different Toxoplasma strains, representing global diversity, and used RNA-sequencing to determine host and parasite transcriptomes. We identified large differences between strains in the expression level of known parasite effectors and large chromosomal structural variation in some strains. We also identified novel strain-specifically regulated host pathways, including the regulation of the type I interferon response by some atypical strains. IFNβ production by infected cells was associated with parasite killing, independent of interferon gamma activation, and dependent on endosomal Toll-like receptors in macrophages and the cytoplasmic receptor retinoic acid-inducible gene 1 (RIG-I) in fibroblasts.
Lindfors, Ninita; Lund, Henrik; Johansson, Hans; Ekestubbe, Annika
2017-01-01
The aim of this in vitro study was to evaluate how a deviation from the horizontal plane, affects the image quality in two different CBCT-devices. A phantom head SK150 (RANDO, The Phantom Laboratory, Salem, NY, USA) was examined in two CBCT-units: Accuitomo 80 and Veraviewepocs 3D R100 (J. Morita Mfg. Corp. Kyoto, Japan). The phantom head was placed with the hard palate parallel to the horizontal plane and tilted 20 ° backwards. Exposures were performed with different field of views (FOVs), voxel sizes, slice thicknesses and exposure settings. Effective dose was calculated using PCXMC 2.0 (STUK, Helsinki, Finland). Image quality was assessed using contrast-to-noise-ratio (CNR). Region of interest (ROI) was set at three different levels of the mandibular bone and soft tissue, uni- and bilaterally in small and large FOVs, respectively. CNR values were calculated by CT-value and standard deviation for each ROI. Factor analysis was used to analyze the material. Tilting the phantom head backwards rendered significantly higher mean CNR values regardless of FOV. The effective dose was lower in small than in large FOVs and varied to a larger extent between CBCT-devices in large FOVs. Head position can affect the image quality. Tilting the head backward improved image quality in the mandibular region. However, if influenced by other variables e.g. motion artifacts in a clinical situation, remains to be further investigated. Image quality assessed using CNR values to investigate the influence of different patient positions and FOVs.
Distribution of fixed beneficial mutations and the rate of adaptation in asexual populations
Good, Benjamin H.; Rouzine, Igor M.; Balick, Daniel J.; Hallatschek, Oskar; Desai, Michael M.
2012-01-01
When large asexual populations adapt, competition between simultaneously segregating mutations slows the rate of adaptation and restricts the set of mutations that eventually fix. This phenomenon of interference arises from competition between mutations of different strengths as well as competition between mutations that arise on different fitness backgrounds. Previous work has explored each of these effects in isolation, but the way they combine to influence the dynamics of adaptation remains largely unknown. Here, we describe a theoretical model to treat both aspects of interference in large populations. We calculate the rate of adaptation and the distribution of fixed mutational effects accumulated by the population. We focus particular attention on the case when the effects of beneficial mutations are exponentially distributed, as well as on a more general class of exponential-like distributions. In both cases, we show that the rate of adaptation and the influence of genetic background on the fixation of new mutants is equivalent to an effective model with a single selection coefficient and rescaled mutation rate, and we explicitly calculate these effective parameters. We find that the effective selection coefficient exactly coincides with the most common fixed mutational effect. This equivalence leads to an intuitive picture of the relative importance of different types of interference effects, which can shift dramatically as a function of the population size, mutation rate, and the underlying distribution of fitness effects. PMID:22371564
Tinnitus: A Large VBM-EEG Correlational Study
Vanneste, Sven; Van De Heyning, Paul; De Ridder, Dirk
2015-01-01
A surprising fact in voxel-based morphometry (VBM) studies performed in tinnitus is that not one single region is replicated in studies of different centers. The question then rises whether this is related to the low sample size of these studies, the selection of non-representative patient subgroups, or the absence of stratification according to clinical characteristics. Another possibility is that VBM is not a good tool to study functional pathologies such as tinnitus, in contrast to pathologies like Alzheimer’s disease where it is known the pathology is related to cell loss. In a large sample of 154 tinnitus patients VBM and QEEG (Quantitative Electroencephalography) was performed and evaluated by a regression analysis. Correlation analyses are performed between VBM and QEEG data. Uncorrected data demonstrated structural differences in grey matter in hippocampal and cerebellar areas related to tinnitus related distress and tinnitus duration. After control for multiple comparisons, only cerebellar VBM changes remain significantly altered. Electrophysiological differences are related to distress, tinnitus intensity, and tinnitus duration in the subgenual anterior cingulate cortex, dorsal anterior cingulate cortex, hippocampus, and parahippocampus, which confirms previous results. The absence of QEEG-VBM correlations suggest functional changes are not reflected by co-occurring structural changes in tinnitus, and the absence of VBM changes (except for the cerebellum) that survive correct statistical analysis in a large study population suggests that VBM might not be very sensitive for studying tinnitus. PMID:25781934
Tinnitus: a large VBM-EEG correlational study.
Vanneste, Sven; Van De Heyning, Paul; De Ridder, Dirk
2015-01-01
A surprising fact in voxel-based morphometry (VBM) studies performed in tinnitus is that not one single region is replicated in studies of different centers. The question then rises whether this is related to the low sample size of these studies, the selection of non-representative patient subgroups, or the absence of stratification according to clinical characteristics. Another possibility is that VBM is not a good tool to study functional pathologies such as tinnitus, in contrast to pathologies like Alzheimer's disease where it is known the pathology is related to cell loss. In a large sample of 154 tinnitus patients VBM and QEEG (Quantitative Electroencephalography) was performed and evaluated by a regression analysis. Correlation analyses are performed between VBM and QEEG data. Uncorrected data demonstrated structural differences in grey matter in hippocampal and cerebellar areas related to tinnitus related distress and tinnitus duration. After control for multiple comparisons, only cerebellar VBM changes remain significantly altered. Electrophysiological differences are related to distress, tinnitus intensity, and tinnitus duration in the subgenual anterior cingulate cortex, dorsal anterior cingulate cortex, hippocampus, and parahippocampus, which confirms previous results. The absence of QEEG-VBM correlations suggest functional changes are not reflected by co-occurring structural changes in tinnitus, and the absence of VBM changes (except for the cerebellum) that survive correct statistical analysis in a large study population suggests that VBM might not be very sensitive for studying tinnitus.
Trends in the Training Recruits Receive Before their First Fleet Assignments
2011-07-01
length of time to the fleet over the last 14 years. We compare them among recruits with different initial obligations ( 4YOs and 6YOs). We also...time and time not in school decreased on average, for both 4YOs and 6YOs, we found that NUI time actually increased for 4YOs and remained very...unstable over time for 6YOs. Both 4YOs and 6YOs were recently less likely to participate in follow-on training after A-school. We saw a large decline in
Brucellosis update in Libya and regional prospective
Ahmed, Mohamed O; Abouzeed, Yousef M; Bennour, Emad M; van Velkinburgh, Jennifer C
2015-01-01
Brucellosis is a global bacterial zoonosis responsible for high morbidity in humans and significant livestock economic losses. While brucellosis remains a public health concern worldwide, its global geographic distribution is variable, largely due to different management schemes; however, paucity of information renders the status of brucellosis unclear and incomplete in many countries, especially those with low income and under-developed infrastructure. This short article summarizes and discusses recent important updates on brucellosis from the North African countries, with a particular brief emphasis on the current status and recent updates in Libya. PMID:25578285
Brucellosis update in Libya and regional prospective.
Ahmed, Mohamed O; Abouzeed, Yousef M; Bennour, Emad M; van Velkinburgh, Jennifer C
2015-02-01
Brucellosis is a global bacterial zoonosis responsible for high morbidity in humans and significant livestock economic losses. While brucellosis remains a public health concern worldwide, its global geographic distribution is variable, largely due to different management schemes; however, paucity of information renders the status of brucellosis unclear and incomplete in many countries, especially those with low income and under-developed infrastructure. This short article summarizes and discusses recent important updates on brucellosis from the North African countries, with a particular brief emphasis on the current status and recent updates in Libya.
[Squirting and female ejaculation in 2015?].
Salama, S; Boitrelle, F; Gauquelin, A; Lesaffre, C; Thiounn, N; Desvaux, P
2015-06-01
Since Antiquity, women who expulse a large quantity of liquid during sexual stimulation have remained a mystery. This phenomena is usually called "squirting". Many physicians have proposed different explications, however, there are very few scientific publications and their conclusions are discordant. Today, squirting is fashionable in the media, and some recent studies have brought new information. Through medical publications, we present the conclusions concerning the origin and the nature of squirting, the psychological experience of these squirting women and the feelings of their partners. Copyright © 2015 Elsevier Masson SAS. All rights reserved.
Hadron Mass Effects: Kaons at HERMES vs. COMPASS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Guerrero Teran, Juan V.; Accardi, Alberto
Experimental data for integrated kaon multiplicities taken at HERMES and COMPASS measurements look incompatible with each other. In this talk, we investigate the effects of hadron masses calculated at leading-order and leading twist at the kinematics of these two experiments. We present evidence that Hadron Mass Corrections can fully reconcile the data for the K+/K- multiplicity ratio, and can also sizeably reduce the apparent large discrepancy in the case of K++K- data. Residual differences in the shape of the latter one remains to be understood.
David, A S; Farrin, L; Hull, L; Unwin, C; Wessely, S; Wykes, T
2002-11-01
Complaints of poor memory and concentration are common in veterans of the 1991 Persian Gulf War as are other symptoms. Despite a large research effort, such symptoms remain largely unexplained. A comprehensive battery of neuropsychological tests and rating scales was administered to 341 UK servicemen who were returnees from the Gulf War and peace keeping duties in Bosnia, plus non-deployed military controls. All were drawn from a large randomized survey. Most were selected on the basis of impaired physical functioning defined operationally. Group comparisons revealed an association between physical functioning and symptoms of depression, post-traumatic stress reactions, increased anger and subjective cognitive failures. Poorer performance on some general cognitive measures, sequencing and attention was also seen in association with being 'ill' but virtually all differences disappeared after adjusting for depressed mood or multiple comparisons. Deployment was also associated with symptoms of post-traumatic stress and subjective cognitive failures, independently of health status, as well as minor general cognitive and constructional impairment. The latter remained significantly poorer in the Gulf group even after adjusting for depressed mood. Disturbances of mood are more prominent than quantifiable cognitive deficits in Gulf War veterans and probably lead to subjective underestimation of ability. Task performance deficits can themselves be explained by depressed mood although the direction of causality cannot be inferred confidently. Reduced constructional ability cannot be explained in this way and could be an effect of Gulf-specific exposures.
A Spur to Atavism: Placing Platypus Poison.
Hobbins, Peter
2015-11-01
For over two centuries, the platypus (Ornithorhynchus anatinus) has been constructed and categorized in multiple ways. An unprecedented mélange of anatomical features and physiological functions, it long remained a systematic quandary. Nevertheless, since 1797, naturalists and biologists have pursued two recurring obsessions. Investigations into platypus reproduction and lactation have focused attention largely upon females of the species. Despite its apparent admixture of avian, reptilian and mammalian characters, the platypus was soon placed as a rudimentary mammal--primitive, naïve and harmless. This article pursues a different taxonomic trajectory, concentrating on a specifically male anatomical development: the crural spur and venom gland on the hind legs. Once the defining characteristic of both the platypus and echidna (Tachyglossus aculeatus), by 1830 this sexed spur had been largely dismissed as inactive and irrelevant. For a creature regularly depicted as a biological outlier, the systematic and evolutionary implications of platypus poison have remained largely overlooked. In Australia, however, sporadic cases of 'spiking' led to consistent homologies being remarked between the platypus crural system and the venom glands of snakes. As with its reproductive reliance upon eggs, possession of an endogenous poison suggested significant reptilian affinities, yet the platypus has rarely been classed as an advanced reptile. Indeed, ongoing uncertainty regarding the biological purpose of the male's spur has ostensibly posed a directional puzzle. As with so many of its traits, however, platypus poison has been consistently described as a redundant remnant, rather than an emergent feature indicating evolutionary advance.
NASA Astrophysics Data System (ADS)
Sporea, R. A.; Trainor, M. J.; Young, N. D.; Shannon, J. M.; Silva, S. R. P.
2014-03-01
Ultra-large-scale integrated (ULSI) circuits have benefited from successive refinements in device architecture for enormous improvements in speed, power efficiency and areal density. In large-area electronics (LAE), however, the basic building-block, the thin-film field-effect transistor (TFT) has largely remained static. Now, a device concept with fundamentally different operation, the source-gated transistor (SGT) opens the possibility of unprecedented functionality in future low-cost LAE. With its simple structure and operational characteristics of low saturation voltage, stability under electrical stress and large intrinsic gain, the SGT is ideally suited for LAE analog applications. Here, we show using measurements on polysilicon devices that these characteristics lead to substantial improvements in gain, noise margin, power-delay product and overall circuit robustness in digital SGT-based designs. These findings have far-reaching consequences, as LAE will form the technological basis for a variety of future developments in the biomedical, civil engineering, remote sensing, artificial skin areas, as well as wearable and ubiquitous computing, or lightweight applications for space exploration.
Sporea, R. A.; Trainor, M. J.; Young, N. D.; Shannon, J. M.; Silva, S. R. P.
2014-01-01
Ultra-large-scale integrated (ULSI) circuits have benefited from successive refinements in device architecture for enormous improvements in speed, power efficiency and areal density. In large-area electronics (LAE), however, the basic building-block, the thin-film field-effect transistor (TFT) has largely remained static. Now, a device concept with fundamentally different operation, the source-gated transistor (SGT) opens the possibility of unprecedented functionality in future low-cost LAE. With its simple structure and operational characteristics of low saturation voltage, stability under electrical stress and large intrinsic gain, the SGT is ideally suited for LAE analog applications. Here, we show using measurements on polysilicon devices that these characteristics lead to substantial improvements in gain, noise margin, power-delay product and overall circuit robustness in digital SGT-based designs. These findings have far-reaching consequences, as LAE will form the technological basis for a variety of future developments in the biomedical, civil engineering, remote sensing, artificial skin areas, as well as wearable and ubiquitous computing, or lightweight applications for space exploration. PMID:24599023
Sim, Doo Sun; Ahn, Youngkeun; Kim, Young Jo; Chae, Shung Chull; Hong, Taek Jong; Seong, In Whan; Chae, Jei Keon; Kim, Chong Jin; Cho, Myeong Chan; Seung, Ki Bae; Park, Seung Jung
2011-01-01
This study compared clinical outcomes of drug-eluting stents (DES) versus bare-metal stents (BMS) in large coronary arteries in patients with acute myocardial infarction (MI). A total of 985 patients who underwent single-vessel percutaneous coronary intervention (PCI) in large coronary arteries (≥ 3.5 mm) in lesions < 25 mm were divided into DES group (n = 841) and BMS group (n = 144). Clinical outcomes during 12 months were compared. In-hospital outcome was similar between the groups. At six months, death/MI rate was not different. However, DES group had significantly lower rates of target-lesion revascularization (TLR) (1.7% vs 5.6%, P = 0.021), target-vessel revascularization (TVR) (2.2% vs 5.6%, P = 0.032), and total major adverse cardiac events (MACE) (3.4% vs 11.9%, P = 0.025). At 12 months, the rates of TLR and TVR remained lower in the DES group (2.5% vs 5.9%, P = 0.032 and 5.9% vs 3.1%, P = 0.041), but the rates of death/MI and total MACE were not statistically different. The use of DES in large vessels in the setting of acute MI is associated with lower need for repeat revascularization compared to BMS without compromising the overall safety over the course of one-year follow-up. PMID:21468259
Blanco Gonzalez, Enrique; Aritaki, Masato; Knutsen, Halvor; Taniguchi, Nobuhiko
2015-01-01
Large-scale hatchery releases are carried out for many marine fish species worldwide; nevertheless, the long-term effects of this practice on the genetic structure of natural populations remains unclear. The lack of knowledge is especially evident when independent stock enhancement programs are conducted simultaneously on the same species at different geographical locations, as occurs with red sea bream (Pagrus major, Temminck et Schlegel) in Japan. In this study, we examined the putative effects of intensive offspring releases on the genetic structure of red sea bream populations along the Japanese archipelago by genotyping 848 fish at fifteen microsatellite loci. Our results suggests weak but consistent patterns of genetic divergence (F(ST) = 0.002, p < 0.001). Red sea bream in Japan appeared spatially structured with several patches of distinct allelic composition, which corresponded to areas receiving an important influx of fish of hatchery origin, either released intentionally or from unintentional escapees from aquaculture operations. In addition to impacts upon local populations inhabiting semi-enclosed embayments, large-scale releases (either intentionally or from unintentional escapes) appeared also to have perturbed genetic structure in open areas. Hence, results of the present study suggest that independent large-scale marine stock enhancement programs conducted simultaneously on one species at different geographical locations may compromise native genetic structure and lead to patchy patterns in population genetic structure.
What Determines Upscale Growth of Oceanic Convection into MCSs?
NASA Astrophysics Data System (ADS)
Zipser, E. J.
2017-12-01
Over tropical oceans, widely scattered convection of various depths may or may not grow upscale into mesoscale convective systems (MCSs). But what distinguishes the large-scale environment that favors such upscale growth from that favoring "unorganized", scattered convection? Is it some combination of large-scale low-level convergence and ascending motion, combined with sufficient instability? We recently put this to a test with ERA-I reanalysis data, with disappointing results. The "usual suspects" of total column water vapor, large-scale ascent, and CAPE may all be required to some extent, but their differences between large MCSs and scattered convection are small. The main positive results from this work (already published) demonstrate that the strength of convection is well correlated with the size and perhaps "organization" of convective features over tropical oceans, in contrast to tropical land, where strong convection is common for large or small convective features. So, important questions remain: Over tropical oceans, how should we define "organized" convection? By size of the precipitation area? And what environmental conditions lead to larger and better organized MCSs? Some recent attempts to answer these questions will be described, but good answers may require more data, and more insights.
Mascherek, Anna C.
2017-01-01
Safety Climate has been acknowledged as an unspecific factor influencing patient safety. However, studies rarely provide in-depth analysis of climate data. As a helpful approach, the concept of “climate strength” has been proposed. In the present study we tested the hypotheses that even if safety climate remains stable on mean-level across time, differences might be evident in strength or shape. The data of two hospitals participating in a large national quality improvement program were analysed for differences in climate profiles at two measurement occasions. We analysed differences on mean-level, differences in percent problematic response, agreement within groups, and frequency histograms in two large hospitals in Switzerland at two measurement occasions (2013 and 2015) applying the Safety Climate Survey. In total, survey responses of 1193 individuals were included in the analyses. Overall, small but significant differences on mean-level of safety climate emerged for some subgroups. Also, although agreement was strong at both time-points within groups, tendencies of divergence or consensus were present in both hospitals. Depending on subgroup and analyses chosen, differences were more or less pronounced. The present study illustrated that taking several measures into account and describing safety climate from different perspectives is necessary in order to fully understand differences and trends within groups and to develop interventions addressing the needs of different groups more precisely. PMID:28753633
Manek, Aditya K.; Ferrari, Maud C. O.; Pollock, Robyn J.; Vicente, Daniel; Weber, Lynn P.; Chivers, Douglas P.
2013-01-01
Many prey fishes possess large club cells in their epidermis. The role of these cells has garnered considerable attention from evolutionary ecologists. These cells likely form part of the innate immune system of fishes, however, they also have an alarm function, releasing chemical cues that serve to warn nearby conspecifics of danger. Experiments aimed at understanding the selection pressures leading to the evolution of these cells have been hampered by a surprisingly large intraspecific variation in epidermal club cell (ECC) investment. The goal of our current work was to explore the magnitude and nature of this variation in ECC investment. In a field survey, we documented large differences in ECC investment both within and between several populations of minnows. We then tested whether we could experimentally reduce variation in mean ECC number by raising fish under standard laboratory conditions for 4 weeks. Fish from different populations responded very differently to being held under standard laboratory conditions; some populations showed an increase in ECC investment while others remained unchanged. More importantly, we found some evidence that we could reduce within population variation in ECC investment through time, but could not reduce among-population variation in mean ECC investment. Given the large variation we observed in wild fish and our limited ability to converge mean cell number by holding the fish under standard conditions, we caution that future studies may be hard pressed to find subtle effects of various experimental manipulations; this will make elucidating the selection pressures leading to the evolution of the cells challenging. PMID:23469175
Urban, Lorien E; Roberts, Susan B; Fierstein, Jamie L; Gary, Christine E; Lichtenstein, Alice H
2014-12-31
Intakes of sodium, saturated fat, and trans fat remain high despite recommendations to limit these nutrients for cardiometabolic risk reduction. A major contributor to intake of these nutrients is foods prepared outside the home, particularly from fast-food restaurants. We analyzed the nutrient content of frequently ordered items from 3 US national fast-food chains: fried potatoes (large French fries), cheeseburgers (2-oz and 4-oz), and a grilled chicken sandwich. We used an archival website to obtain data on sodium, saturated fat, and trans fat content for these items from 2000 through 2013. The amount of each nutrient per 1,000 kcal was calculated to determine whether there were trends in product reformulation. Sodium content per 1,000 kcal differed widely among the 3 chains by food item, precluding generalizations across chains. During the 14-year period, sodium content per 1,000 kcal for large French fries remained high for all 3 chains, although the range narrowed from 316-2,000 mg per 1,000 kcal in 2000 to 700-1,420 mg per 1,000 kcal in 2013. Among the items assessed, cheeseburgers were the main contributor of saturated fat, and there was little change in content per 1,000 kcal for this item during the 14-year period. In contrast, there was a sharp decline in saturated and trans fat content of large French fries per 1,000 kcal. Post-2009, the major contributor of trans fat per 1,000 kcal was cheeseburgers; trans fat content of this item remained stable during the 14-year period. With the exception of French fries, little evidence was found during the 14-year period of product reformulation by restaurants to become more consistent with dietary guidance to reduce intakes of sodium and saturated fat.
2012-01-01
Diffuse large B-cell lymphoma (DLBCL) is the most common type of non-Hodgkin Lymphoma comprising of greater than 30% of adult non-Hodgkin Lymphomas. DLBCL represents a diverse set of lymphomas, defined as diffuse proliferation of large B lymphoid cells. Numerous cytogenetic studies including karyotypes and fluorescent in situ hybridization (FISH), as well as morphological, biological, clinical, microarray and sequencing technologies have attempted to categorize DLBCL into morphological variants, molecular and immunophenotypic subgroups, as well as distinct disease entities. Despite such efforts, most lymphoma remains undistinguishable and falls into DLBCL, not otherwise specified (DLBCL-NOS). The advent of microarray-based studies (chromosome, RNA, gene expression, etc) has provided a plethora of high-resolution data that could potentially facilitate the finer classification of DLBCL. This review covers the microarray data currently published for DLBCL. We will focus on these types of data; 1) array based CGH; 2) classical CGH; and 3) gene expression profiling studies. The aims of this review were three-fold: (1) to catalog chromosome loci that are present in at least 20% or more of distinct DLBCL subtypes; a detailed list of gains and losses for different subtypes was generated in a table form to illustrate specific chromosome loci affected in selected subtypes; (2) to determine common and distinct copy number alterations among the different subtypes and based on this information, characteristic and similar chromosome loci for the different subtypes were depicted in two separate chromosome ideograms; and, (3) to list re-classified subtypes and those that remained indistinguishable after review of the microarray data. To the best of our knowledge, this is the first effort to compile and review available literatures on microarray analysis data and their practical utility in classifying DLBCL subtypes. Although conventional cytogenetic methods such as Karyotypes and FISH have played a major role in classification schemes of lymphomas, better classification models are clearly needed to further understanding the biology, disease outcome and therapeutic management of DLBCL. In summary, microarray data reviewed here can provide better subtype specific classifications models for DLBCL. PMID:22967872
Rosskopf, Johannes; Müller, Hans-Peter; Dreyhaupt, Jens; Gorges, Martin; Ludolph, Albert C; Kassubek, Jan
2015-03-01
Diffusion tensor imaging (DTI) for assessing ALS-associated white matter alterations has still not reached the level of a neuroimaging biomarker. Since large-scale multicentre DTI studies in ALS may be hampered by differences in scanning protocols, an approach for pooling of DTI data acquired with different protocols was investigated. Three hundred and nine datasets from 170 ALS patients and 139 controls were collected ex post facto from a monocentric database reflecting different scanning protocols. A 3D correction algorithm was introduced for a combined analysis of DTI metrics despite different acquisition protocols, with the focus on the CST as the tract correlate of ALS neuropathological stage 1. A homogenous set of data was obtained by application of 3D correction matrices. Results showed that a fractional anisotropy (FA) threshold of 0.41 could be defined to discriminate ALS patients from controls (sensitivity/specificity, 74%/72%). For the remaining test sample, sensitivity/specificity values of 68%/74% were obtained. In conclusion, the objective was to merge data recorded with different DTI protocols with 3D correction matrices for analyses at group level. These post processing tools might facilitate analysis of large study samples in a multicentre setting for DTI analysis at group level to aid in establishing DTI as a non-invasive biomarker for ALS.
Role of rasagiline in treating Parkinson's disease: Effect on disease progression.
Malaty, Irene A; Fernandez, Hubert H
2009-08-01
Rasagiline is a second generation, selective, irreversible monoamine oxidase type B (MAO-B) inhibitor. It has demonstrated efficacy in monotherapy for early Parkinson's disease (PD) patients in one large randomized, placebo-controlled trial (TVP-1012 in Early Monotherapy for Parkinson's Disease Outpatients), and has shown ability to reduce off time in more advanced PD patients with motor fluctuations in two large placebo-controlled trials (Parkinson's Rasagiline: Efficacy and Safety in the Treatment of "Off", and Lasting Effect in Adjunct Therapy With Rasagiline Given Once Daily). Preclinical data abound to suggest potential for neuroprotection by this compound against a variety of neurotoxic insults in cell cultures and in animals. The lack of amphetamine metabolites provides an advantage over the first generation MAO-B inhibitor selegiline. One large trial has investigated the potential for disease modification in PD patients (Attenuation of Disease progression with Azilect Given Once-daily) and preliminary results maintain some possible advantage to earlier initiation of the 1 mg/day dose. The clinical significance of the difference detected remains a consideration.
The transition to value-based care.
Ray, Jordan C; Kusumoto, Fred
2016-10-01
Delivery of medical care is evolving rapidly worldwide. Over the past several years in the USA, there has been a rapid shift in reimbursement from a simple fee-for-service model to more complex models that attempt to link payment to quality and value. Change in any large system can be difficult, but with medicine, the transition to a value-based system has been particularly hard to implement because both quality and cost are difficult to quantify. Professional societies and other medical groups are developing different programs in an attempt to define high value care. However, applying a national standard of value for any treatment is challenging, since value varies from person to person, and the individual benefit must remain the central tenet for delivering best patient-centered medical care. Regardless of the specific operational features of the rapidly changing healthcare environment, physicians must first and foremost always remain patient advocates.
What Can Plasticity Contribute to Insect Responses to Climate Change?
Sgrò, Carla M; Terblanche, John S; Hoffmann, Ary A
2016-01-01
Plastic responses figure prominently in discussions on insect adaptation to climate change. Here we review the different types of plastic responses and whether they contribute much to adaptation. Under climate change, plastic responses involving diapause are often critical for population persistence, but key diapause responses under dry and hot conditions remain poorly understood. Climate variability can impose large fitness costs on insects showing diapause and other life cycle responses, threatening population persistence. In response to stressful climatic conditions, insects also undergo ontogenetic changes including hardening and acclimation. Environmental conditions experienced across developmental stages or by prior generations can influence hardening and acclimation, although evidence for the latter remains weak. Costs and constraints influence patterns of plasticity across insect clades, but they are poorly understood within field contexts. Plastic responses and their evolution should be considered when predicting vulnerability to climate change-but meaningful empirical data lag behind theory.
Natural history of acute and chronic hepatitis C.
Maasoumy, Benjamin; Wedemeyer, Heiner
2012-08-01
Hepatitis C virus (HCV) infection remains a major global health burden. Hepatitis C causes significant liver-related morbidity and mortality due to hepatic decompensation and development of hepatocellular carcinoma. In addition, extra-hepatic manifestations of hepatitis C are frequent. There is a very large interindividual variability in the natural history of both acute and chronic hepatitis C which can be explained in part by a combination of various host, viral and environmental factors. Successful antiviral treatment can prevent short- and long-term complications of HCV infection in many patients. Still, the relative contribution of distinct risk factors for disease progression in different phases of HCV infection needs to be better defined. Personalized treatment approaches for HCV infection should consider individual risk profiles to avoid both under- and over-treatment - which will remain important also in upcoming era of interferon-free treatment of hepatitis C. Copyright © 2012. Published by Elsevier Ltd.
Moroz, Andrei; Deffune, Elenice
2013-11-01
Platelet-rich plasma has been largely used as a therapeutic option for the treatment of chronic wounds of different etiologies. The enhanced regeneration observed after the use of platelet-rich plasma has been systematically attributed to the growth factors that are present inside platelets' granules. We hypothesize that the remaining plasma and platelet-bound fibronectin may act as a further bioactive protein in platelet-rich plasma preparations. Recent reports were analyzed and presented as direct evidences of this hypotheses. Fibronectin may directly influence the extracellular matrix remodeling during wound repair. This effect is probably through matrix metalloproteinase expression, thus exerting an extra effect on chronic wound regeneration. Physicians should be well aware of the possible fibronectin-induced effects in their future endeavors with PRP in chronic wound treatment. Copyright © 2013 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.
Origins of timed cancer treatment: early marker rhythm-guided individualized chronochemotherapy*
Halberg, Franz; Prem, Konald; Halberg, Francine; Norman, Catherine; Cornélissen, Germaine
2008-01-01
A 21-year old patient who presented in 1973 with a rare and highly malignant ovarian endodermal sinus tumor with spillage into the peritoneal cavity is alive and well today after receiving chronochemotherapy. During the first four courses of treatment, medications were given at different circadian stages. Complete blood counts and marker variables such as mood, vigor, nausea, and temperature were monitored around the clock and analyzed by cosinor to seek times of highest tolerance. Remaining treatment courses were administered at a time corresponding to the patient's best drug tolerance, rather than extrapolating the timing of optimal cyclophosphamide administration from also-implemented parallel laboratory studies on mice. Notwithstanding remaining hurdles in bringing chronochemotherapy to the clinic for routine care, merits of marker rhythm-guided chronotherapy documented in this and other case reports have led to the doubling of the two-year disease-free survival of patients with large perioral tumors in a clinical trial. PMID:17228525
NASA Technical Reports Server (NTRS)
Jones, J. H.; Niles, P. B.; Webster, C. R.; Mahaffy, P. R.; Flesch, G. J.; Christensen, L. E.; Leshin, L. A.; Franz, H.; Wong, M.; Atreya, S. K.;
2013-01-01
Given the broad agreement between C, H, and O isotopic ratios in the modern atmosphere and the ALH 84001 meteorite, it is possible that these reservoirs were established after early atmospheric loss prior to 4 Ga. The preservation of these signals over this long period of history can be explained in several slightly different ways: 1) C, O, and H have remained static in the atmosphere and have not exchanged with the surface over the past 4 Ga; 2) C, O, and H in the atmosphere have potentially varied widely over history but have been continually buffered by larger reservoirs in the crust which have remained unchanged over the past 4 Ga. This second possibility allows for potentially large variations in atmospheric pressure to occur as CO2 is recycled back into the atmosphere from crustal reservoirs or degassed from the mantle.
Modeling of rapid shutdown in the DIII-D tokamak by core deposition of high-Z material
Izzo, Valerie A.; Parks, Paul B.
2017-06-22
MHD modeling of shell-pellet injection for disruption mitigation is carried out under the assumption of idealized delivery of the radiating payload to the core, neglecting the physics of shell ablation. The shell pellet method is designed to produce an inside-out thermal quench in which core thermal heat is radiated while outer flux surfaces remain intact, protecting the divertor from large conducted heat loads. In the simulation, good outer surfaces remain until the thermal quench is nearly complete, and a high radiated energy fraction is achieved. As a result, when the outermost surfaces are destroyed, runaway electron test orbits indicate thatmore » the rate of runaway electron loss is very fast compared with prior massive gas injection simulations, which is attributed to the very different current profile evolution that occurs with central cooling.« less
Neural correlates of socioeconomic status in the developing human brain.
Noble, Kimberly G; Houston, Suzanne M; Kan, Eric; Sowell, Elizabeth R
2012-07-01
Socioeconomic disparities in childhood are associated with remarkable differences in cognitive and socio-emotional development during a time when dramatic changes are occurring in the brain. Yet, the neurobiological pathways through which socioeconomic status (SES) shapes development remain poorly understood. Behavioral evidence suggests that language, memory, social-emotional processing, and cognitive control exhibit relatively large differences across SES. Here we investigated whether volumetric differences could be observed across SES in several neural regions that support these skills. In a sample of 60 socioeconomically diverse children, highly significant SES differences in regional brain volume were observed in the hippocampus and the amygdala. In addition, SES × age interactions were observed in the left superior temporal gyrus and left inferior frontal gyrus, suggesting increasing SES differences with age in these regions. These results were not explained by differences in gender, race or IQ. Likely mechanisms include differences in the home linguistic environment and exposure to stress, which may serve as targets for intervention at a time of high neural plasticity. © 2012 Blackwell Publishing Ltd.
Messé, Arnaud; Rudrauf, David; Benali, Habib; Marrelec, Guillaume
2014-01-01
Investigating the relationship between brain structure and function is a central endeavor for neuroscience research. Yet, the mechanisms shaping this relationship largely remain to be elucidated and are highly debated. In particular, the existence and relative contributions of anatomical constraints and dynamical physiological mechanisms of different types remain to be established. We addressed this issue by systematically comparing functional connectivity (FC) from resting-state functional magnetic resonance imaging data with simulations from increasingly complex computational models, and by manipulating anatomical connectivity obtained from fiber tractography based on diffusion-weighted imaging. We hypothesized that FC reflects the interplay of at least three types of components: (i) a backbone of anatomical connectivity, (ii) a stationary dynamical regime directly driven by the underlying anatomy, and (iii) other stationary and non-stationary dynamics not directly related to the anatomy. We showed that anatomical connectivity alone accounts for up to 15% of FC variance; that there is a stationary regime accounting for up to an additional 20% of variance and that this regime can be associated to a stationary FC; that a simple stationary model of FC better explains FC than more complex models; and that there is a large remaining variance (around 65%), which must contain the non-stationarities of FC evidenced in the literature. We also show that homotopic connections across cerebral hemispheres, which are typically improperly estimated, play a strong role in shaping all aspects of FC, notably indirect connections and the topographic organization of brain networks. PMID:24651524
de Blois, Sylvie
2016-01-01
Projecting suitable conditions for a species as a function of future climate provides a reasonable, although admittedly imperfect, spatially explicit estimate of species vulnerability associated with climate change. Projections emphasizing range shifts at continental scale, however, can mask contrasting patterns at local or regional scale where management and policy decisions are made. Moreover, models usually show potential for areas to become climatically unsuitable, remain suitable, or become suitable for a particular species with climate change, but each of these outcomes raises markedly different ecological and management issues. Managing forest decline at sites where climatic stress is projected to increase is likely to be the most immediate challenge resulting from climate change. Here we assess habitat suitability with climate change for five dominant tree species of eastern North American forests, focusing on areas of greatest vulnerability (loss of suitability in the baseline range) in Quebec (Canada) rather than opportunities (increase in suitability). Results show that these species are at risk of maladaptation over a remarkably large proportion of their baseline range. Depending on species, 5–21% of currently climatically suitable habitats are projected to be at risk of becoming unsuitable. This suggests that species that have traditionally defined whole regional vegetation assemblages could become less adapted to these regions, with significant impact on ecosystems and forest economy. In spite of their well-recognised limitations and the uncertainty that remains, regionally-explicit risk assessment approaches remain one of the best options to convey that message and the need for climate policies and forest management adaptation strategies. PMID:27478706
Extreme Beta-Cell Deficiency in Pancreata of Dogs with Canine Diabetes
Shields, Emily J.; Lam, Carol J.; Cox, Aaron R.; Rankin, Matthew M.; Van Winkle, Thomas J.; Hess, Rebecka S.; Kushner, Jake A.
2015-01-01
The pathophysiology of canine diabetes remains poorly understood, in part due to enigmatic clinical features and the lack of detailed histopathology studies. Canine diabetes, similar to human type 1 diabetes, is frequently associated with diabetic ketoacidosis at onset or after insulin omission. However, notable differences exist. Whereas human type 1 diabetes often occurs in children, canine diabetes is typically described in middle age to elderly dogs. Many competing theories have been proposed regarding the underlying cause of canine diabetes, from pancreatic atrophy to chronic pancreatitis to autoimmune mediated β-cell destruction. It remains unclear to what extent β-cell loss contributes to canine diabetes, as precise quantifications of islet morphometry have not been performed. We used high-throughput microscopy and automated image processing to characterize islet histology in a large collection of pancreata of diabetic dogs. Diabetic pancreata displayed a profound reduction in β-cells and islet endocrine cells. Unlike humans, canine non-diabetic islets are largely comprised of β-cells. Very few β-cells remained in islets of diabetic dogs, even in pancreata from new onset cases. Similarly, total islet endocrine cell number was sharply reduced in diabetic dogs. No compensatory proliferation or lymphocyte infiltration was detected. The majority of pancreata had no evidence of pancreatitis. Thus, canine diabetes is associated with extreme β-cell deficiency in both new and longstanding disease. The β-cell predominant composition of canine islets and the near-total absence of β-cells in new onset elderly diabetic dogs strongly implies that similar to human type 1 diabetes, β-cell loss underlies the pathophysiology of canine diabetes. PMID:26057531
Périé, Catherine; de Blois, Sylvie
2016-01-01
Projecting suitable conditions for a species as a function of future climate provides a reasonable, although admittedly imperfect, spatially explicit estimate of species vulnerability associated with climate change. Projections emphasizing range shifts at continental scale, however, can mask contrasting patterns at local or regional scale where management and policy decisions are made. Moreover, models usually show potential for areas to become climatically unsuitable, remain suitable, or become suitable for a particular species with climate change, but each of these outcomes raises markedly different ecological and management issues. Managing forest decline at sites where climatic stress is projected to increase is likely to be the most immediate challenge resulting from climate change. Here we assess habitat suitability with climate change for five dominant tree species of eastern North American forests, focusing on areas of greatest vulnerability (loss of suitability in the baseline range) in Quebec (Canada) rather than opportunities (increase in suitability). Results show that these species are at risk of maladaptation over a remarkably large proportion of their baseline range. Depending on species, 5-21% of currently climatically suitable habitats are projected to be at risk of becoming unsuitable. This suggests that species that have traditionally defined whole regional vegetation assemblages could become less adapted to these regions, with significant impact on ecosystems and forest economy. In spite of their well-recognised limitations and the uncertainty that remains, regionally-explicit risk assessment approaches remain one of the best options to convey that message and the need for climate policies and forest management adaptation strategies.
Individualized Prediction of Reading Comprehension Ability Using Gray Matter Volume.
Cui, Zaixu; Su, Mengmeng; Li, Liangjie; Shu, Hua; Gong, Gaolang
2018-05-01
Reading comprehension is a crucial reading skill for learning and putatively contains 2 key components: reading decoding and linguistic comprehension. Current understanding of the neural mechanism underlying these reading comprehension components is lacking, and whether and how neuroanatomical features can be used to predict these 2 skills remain largely unexplored. In the present study, we analyzed a large sample from the Human Connectome Project (HCP) dataset and successfully built multivariate predictive models for these 2 skills using whole-brain gray matter volume features. The results showed that these models effectively captured individual differences in these 2 skills and were able to significantly predict these components of reading comprehension for unseen individuals. The strict cross-validation using the HCP cohort and another independent cohort of children demonstrated the model generalizability. The identified gray matter regions contributing to the skill prediction consisted of a wide range of regions covering the putative reading, cerebellum, and subcortical systems. Interestingly, there were gender differences in the predictive models, with the female-specific model overestimating the males' abilities. Moreover, the identified contributing gray matter regions for the female-specific and male-specific models exhibited considerable differences, supporting a gender-dependent neuroanatomical substrate for reading comprehension.
Mg/Ti multilayers: Structural and hydrogen absorption properties
NASA Astrophysics Data System (ADS)
Baldi, A.; Pálsson, G. K.; Gonzalez-Silveira, M.; Schreuders, H.; Slaman, M.; Rector, J. H.; Krishnan, G.; Kooi, B. J.; Walker, G. S.; Fay, M. W.; Hjörvarsson, B.; Wijngaarden, R. J.; Dam, B.; Griessen, R.
2010-06-01
Mg-Ti alloys have uncommon optical and hydrogen absorbing properties, originating from a “spinodal-like” microstructure with a small degree of chemical short-range order in the atomic distribution. In the present study we artificially engineer short-range order by depositing Pd-capped Mg/Ti multilayers with different periodicities. Notwithstanding the large lattice mismatch between Mg and Ti, the as-deposited metallic multilayers show good structural coherence. On exposure to H2 gas a two-step hydrogenation process occurs with the Ti layers forming the hydride before Mg. From in situ measurements of the bilayer thickness Λ at different hydrogen pressures, we observe large out-of-plane expansions of Mg and Ti layers on hydrogenation, indicating strong plastic deformations in the films and a consequent shortening of the coherence length. On unloading at room temperature in air, hydrogen atoms remain trapped in the Ti layers due to kinetic constraints. Such loading/unloading sequence can be explained in terms of the different thermodynamic properties of hydrogen in Mg and Ti, as shown by diffusion calculations on a model multilayered systems. Absorption isotherms measured by hydrogenography can be interpreted as a result of the elastic clamping arising from strongly bonded Mg/Pd and broken Mg/Ti interfaces.
NASA Astrophysics Data System (ADS)
Nishimura, Mitsugu; Baker, Earl W.
1987-06-01
Five recent sediment samples from a variety of North American continental shelves were analyzed for fatty acids (FAs) in the solvent-extractable (SOLEX) lipids as well as four types of non-solvent extractable (NONEX) lipids. The NONEX lipids were operationally defined by the succession of extraction procedure required to recover them. The complete procedure included (i) very mild acid treatment, (ii) HF digestion and (iii) saponification of the sediment residue following exhaustive solvent extraction. The distribution pattern and various compositional parameters of SOLEX FAs in the five sediments were divided into three different groups, indicating the difference of biological sources and also diagenetic factors and processes among the three groups of samples. Nevertheless, the compositions of the corresponding NONEX FAs after acid treatment were surprisingly very similar. This was also true for the remaining NONEX FA groups in the five sediment samples. The findings implied that most of the NONEX FAs reported here are derived directly from living organisms. It is also concluded that a large part of NONEX FAs are much more resistant to biodegradation than we have thought, so that they can form the large percentage of total lipids with increasing depth of water and sediments.
Bramble, Matthew S; Lipson, Allen; Vashist, Neerja; Vilain, Eric
2017-01-02
Sex differences in brain development and postnatal behavior are determined largely by genetic sex and in utero gonadal hormone secretions. In humans however, determining the weight that each of these factors contributes remains a challenge because social influences should also be considered. Cases of disorders of sex development (DSD) provide unique insight into how mutations in genes responsible for gonadal formation can perturb the subsequent developmental hormonal milieu and elicit changes in normal human brain maturation. Specific forms of DSDs such as complete androgen insensitivity syndrome (CAIS), congenital adrenal hyperplasia (CAH), and 5α-reductase deficiency syndrome have variable effects between males and females, and the developmental outcomes of such conditions are largely dependent on sex chromosome composition. Medical and psychological works focused on CAH, CAIS, and 5α-reductase deficiency have helped form the foundation for understanding the roles of genetic and hormonal factors necessary for guiding human brain development. Here we highlight how the three aforementioned DSDs contribute to brain and behavioral phenotypes that can uniquely affect 46,XY and 46,XX individuals in dramatically different fashions. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Structure and function of the mammalian middle ear. I: Large middle ears in small desert mammals.
Mason, Matthew J
2016-02-01
Many species of small desert mammals are known to have expanded auditory bullae. The ears of gerbils and heteromyids have been well described, but much less is known about the middle ear anatomy of other desert mammals. In this study, the middle ears of three gerbils (Meriones, Desmodillus and Gerbillurus), two jerboas (Jaculus) and two sengis (elephant-shrews: Macroscelides and Elephantulus) were examined and compared, using micro-computed tomography and light microscopy. Middle ear cavity expansion has occurred in members of all three groups, apparently in association with an essentially 'freely mobile' ossicular morphology and the development of bony tubes for the middle ear arteries. Cavity expansion can occur in different ways, resulting in different subcavity patterns even between different species of gerbils. Having enlarged middle ear cavities aids low-frequency audition, and several adaptive advantages of low-frequency hearing to small desert mammals have been proposed. However, while Macroscelides was found here to have middle ear cavities so large that together they exceed brain volume, the bullae of Elephantulus are considerably smaller. Why middle ear cavities are enlarged in some desert species but not others remains unclear, but it may relate to microhabitat. © 2015 Anatomical Society.
Dellu-Hagedorn, F
2005-01-01
Inter-individual differences in cognitive capacities of young adult rats have largely been ignored. To explore this variability and its neurobiological bases, the relationships between individual differences in working memory and locomotor responses to novelty and to amphetamine were investigated in SD rats. Groups of good and poor learners were isolated, the latter demonstrating a markedly slower learning of the task compared to performant rats, with more perseverations independently to motivational state. They also presented a much higher increase in amphetamine-induced locomotion that remained significant for more than 1h after the injection. These results provide evidence that variability in cognitive capacities can be used to reveal their neurobiological substrates. They open new perspectives to study a possible cognitive origin of addictive behaviors and to investigate the involvement of these inter-individual differences on those observed later in life.
Age differences in genetic and environmental influences on weight and shape concerns.
Klump, Kelly L; Burt, S Alexandra; Spanos, Alexia; McGue, Matt; Iacono, William G; Wade, Tracey D
2010-12-01
Previous research has shown important developmental shifts ingenetic and environmental influences for disordered eating. However, little research has examined age differences for weight/shape concerns, two key components of eating disorders. The goal of this study was to investigate these age differences in preadolescent, adolescent, young adult, and mid-adult twins. Participants included 2,618 female twins (ages of 10-41 years) from three large twin registries. Shape and weight concerns were assessed with the Eating Disorders Examination Questionnaire. Genetic influences were modest in preadolescent twins, but significant from early-adolescence through middle adulthood. Shared environmental factors showed the opposite pattern, with the largest shared environmental contributions occurring in the youngest age group. Nonshared environmental effects remained relatively constant across age. Findings highlight the importance of age differences in genetic and environmental influences. Possible mechanisms include gene x environment interactions and biological changes associated with key developmental stages. © 2009 by Wiley Periodicals, Inc.
Non-equivalent contributions of maternal and paternal genomes to early plant embryogenesis.
Del Toro-De León, Gerardo; García-Aguilar, Marcelina; Gillmor, C Stewart
2014-10-30
Zygotic genome activation in metazoans typically occurs several hours to a day after fertilization, and thus maternal RNAs and proteins drive early animal embryo development. In plants, despite several molecular studies of post-fertilization transcriptional activation, the timing of zygotic genome activation remains a matter of debate. For example, two recent reports that used different hybrid ecotype combinations for RNA sequence profiling of early Arabidopsis embryo transcriptomes came to divergent conclusions. One identified paternal contributions that varied by gene, but with overall maternal dominance, while the other found that the maternal and paternal genomes are transcriptionally equivalent. Here we assess paternal gene activation functionally in an isogenic background, by performing a large-scale genetic analysis of 49 EMBRYO DEFECTIVE genes and testing the ability of wild-type paternal alleles to complement phenotypes conditioned by mutant maternal alleles. Our results demonstrate that wild-type paternal alleles for nine of these genes are completely functional 2 days after pollination, with the remaining 40 genes showing partial activity beginning at 2, 3 or 5 days after pollination. Using our functional assay, we also demonstrate that different hybrid combinations exhibit significant variation in paternal allele activation, reconciling the apparently contradictory results of previous transcriptional studies. The variation in timing of gene function that we observe confirms that paternal genome activation does not occur in one early discrete step, provides large-scale functional evidence that maternal and paternal genomes make non-equivalent contributions to early plant embryogenesis, and uncovers an unexpectedly profound effect of hybrid genetic backgrounds on paternal gene activity.
Design of Phase II Non-inferiority Trials.
Jung, Sin-Ho
2017-09-01
With the development of inexpensive treatment regimens and less invasive surgical procedures, we are confronted with non-inferiority study objectives. A non-inferiority phase III trial requires a roughly four times larger sample size than that of a similar standard superiority trial. Because of the large required sample size, we often face feasibility issues to open a non-inferiority trial. Furthermore, due to lack of phase II non-inferiority trial design methods, we do not have an opportunity to investigate the efficacy of the experimental therapy through a phase II trial. As a result, we often fail to open a non-inferiority phase III trial and a large number of non-inferiority clinical questions still remain unanswered. In this paper, we want to develop some designs for non-inferiority randomized phase II trials with feasible sample sizes. At first, we review a design method for non-inferiority phase III trials. Subsequently, we propose three different designs for non-inferiority phase II trials that can be used under different settings. Each method is demonstrated with examples. Each of the proposed design methods is shown to require a reasonable sample size for non-inferiority phase II trials. The three different non-inferiority phase II trial designs are used under different settings, but require similar sample sizes that are typical for phase II trials.
Benítez-Benítez, Carmen; Fernández-Mazuecos, Mario; Martín-Bravo, Santiago
2017-01-01
Plants growing in high-mountain environments may share common morphological features through convergent evolution resulting from an adaptative response to similar ecological conditions. The Carex flava species complex (sect. Ceratocystis, Cyperaceae) includes four dwarf morphotypes from Circum-Mediterranean mountains whose taxonomic status has remained obscure due to their apparent morphological resemblance. In this study we investigate whether these dwarf mountain morphotypes result from convergent evolution or common ancestry, and whether there are ecological differences promoting differentiation between the dwarf morphotypes and their taxonomically related large, well-developed counterparts. We used phylogenetic analyses of nrDNA (ITS) and ptDNA (rps16 and 5’trnK) sequences, ancestral state reconstruction, multivariate analyses of macro- and micromorphological data, and species distribution modeling. Dwarf morphotype populations were found to belong to three different genetic lineages, and several morphotype shifts from well-developed to dwarf were suggested by ancestral state reconstructions. Distribution modeling supported differences in climatic niche at regional scale between the large forms, mainly from lowland, and the dwarf mountain morphotypes. Our results suggest that dwarf mountain morphotypes within this sedge group are small forms of different lineages that have recurrently adapted to mountain habitats through convergent evolution. PMID:29281689
Analysis of delay reducing and fuel saving sequencing and spacing algorithms for arrival traffic
NASA Technical Reports Server (NTRS)
Neuman, Frank; Erzberger, Heinz
1991-01-01
The air traffic control subsystem that performs sequencing and spacing is discussed. The function of the sequencing and spacing algorithms is to automatically plan the most efficient landing order and to assign optimally spaced landing times to all arrivals. Several algorithms are described and their statistical performance is examined. Sequencing brings order to an arrival sequence for aircraft. First-come-first-served sequencing (FCFS) establishes a fair order, based on estimated times of arrival, and determines proper separations. Because of the randomness of the arriving traffic, gaps will remain in the sequence of aircraft. Delays are reduced by time-advancing the leading aircraft of each group while still preserving the FCFS order. Tightly spaced groups of aircraft remain with a mix of heavy and large aircraft. Spacing requirements differ for different types of aircraft trailing each other. Traffic is reordered slightly to take advantage of this spacing criterion, thus shortening the groups and reducing average delays. For heavy traffic, delays for different traffic samples vary widely, even when the same set of statistical parameters is used to produce each sample. This report supersedes NASA TM-102795 on the same subject. It includes a new method of time-advance as well as an efficient method of sequencing and spacing for two dependent runways.
Evolution of brain region volumes during artificial selection for relative brain size.
Kotrschal, Alexander; Zeng, Hong-Li; van der Bijl, Wouter; Öhman-Mägi, Caroline; Kotrschal, Kurt; Pelckmans, Kristiaan; Kolm, Niclas
2017-12-01
The vertebrate brain shows an extremely conserved layout across taxa. Still, the relative sizes of separate brain regions vary markedly between species. One interesting pattern is that larger brains seem associated with increased relative sizes only of certain brain regions, for instance telencephalon and cerebellum. Till now, the evolutionary association between separate brain regions and overall brain size is based on comparative evidence and remains experimentally untested. Here, we test the evolutionary response of brain regions to directional selection on brain size in guppies (Poecilia reticulata) selected for large and small relative brain size. In these animals, artificial selection led to a fast response in relative brain size, while body size remained unchanged. We use microcomputer tomography to investigate how the volumes of 11 main brain regions respond to selection for larger versus smaller brains. We found no differences in relative brain region volumes between large- and small-brained animals and only minor sex-specific variation. Also, selection did not change allometric scaling between brain and brain region sizes. Our results suggest that brain regions respond similarly to strong directional selection on relative brain size, which indicates that brain anatomy variation in contemporary species most likely stem from direct selection on key regions. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.
Restoring Forest Landscapes: Important Lessons Learnt
NASA Astrophysics Data System (ADS)
Mansourian, Stephanie; Vallauri, Daniel
2014-02-01
Forest restoration at large scales, or landscapes, is an approach that is increasingly relevant to the practice of environmental conservation. However, implementation remains a challenge; poor monitoring and lesson learning lead to similar mistakes being repeated. The World Wildlife Fund (WWF), the global conservation organization, recently took stock of its 10 years of implementation of forest landscape restoration. A significant body of knowledge has emerged from the work of the WWF and its partners in the different countries, which can be of use to the wider conservation community, but for this to happen, lessons need to be systematically collected and disseminated in a coherent manner to the broader conservation and development communities and, importantly, to policy makers. We use this review of the WWF's experiences and compare and contrast it with other relevant and recent literature to highlight 11 important lessons for future large-scale forest restoration interventions. These lessons are presented using a stepwise approach to the restoration of forested landscapes. We identify the need for long-term commitment and funding, and a concerted and collaborative effort for successful forest landscape restoration. Our review highlights that monitoring impact within landscape-scale forest restoration remains inadequate. We conclude that forest restoration within landscapes is a challenging yet important proposition that has a real but undervalued place in environmental conservation in the twenty-first century.
Five Describing Factors of Dyslexia.
Tamboer, Peter; Vorst, Harrie C M; Oort, Frans J
2016-09-01
Two subtypes of dyslexia (phonological, visual) have been under debate in various studies. However, the number of symptoms of dyslexia described in the literature exceeds the number of subtypes, and underlying relations remain unclear. We investigated underlying cognitive features of dyslexia with exploratory and confirmatory factor analyses. A sample of 446 students (63 with dyslexia) completed a large test battery and a large questionnaire. Five factors were found in both the test battery and the questionnaire. These 10 factors loaded on 5 latent factors (spelling, phonology, short-term memory, rhyme/confusion, and whole-word processing/complexity), which explained 60% of total variance. Three analyses supported the validity of these factors. A confirmatory factor analysis fit with a solution of five factors (RMSEA = .03). Those with dyslexia differed from those without dyslexia on all factors. A combination of five factors provided reliable predictions of dyslexia and nondyslexia (accuracy >90%). We also looked for factorial deficits on an individual level to construct subtypes of dyslexia, but found varying profiles. We concluded that a multiple cognitive deficit model of dyslexia is supported, whereas the existence of subtypes remains unclear. We discussed the results in relation to advanced compensation strategies of students, measures of intelligence, and various correlations within groups of those with and without dyslexia. © Hammill Institute on Disabilities 2014.
(How) Can We Use Satellite Data to Estimate Effects of Extreme Drought on Photosynthesis?
NASA Astrophysics Data System (ADS)
Vicca, S.; Balzarolo, M.; Filella, I.; Granier, A.; Herbst, M.; Knohl, A.; Longdoz, B.; Mund, M.; Nagy, Z.; Pintér, K.; Rambal, S.; Verbesselt, J.; Verger, A.; Zeileis, A.; Zhang, C.; Penuelas, J.
2017-12-01
Severe droughts can strongly impact photosynthesis (GPP), but the tool best suited for large-scale and long-term monitoring, satellite imagery, has yet to prove its ability to detect drought effects on GPP. Especially changes in vegetation functioning when vegetation state remains unaltered (no browning or defoliation) pose a challenge to satellite-derived indicators. We evaluated the performance of different satellite indicators to detect effect of a strong drought (that started during the European heatwave of 2003) on GPP in a beech forest in France (Hesse). While vegetation state remained largely unaffected by the drought, Eddy Covariance data revealed a substantial decrease in GPP and GPP recovered only after about three years. This three-year reduction in GPP was, however not detected by severaly commonly used reflectance indices (like NDVI and FAPAR) or by MODIS GPP product. Only he Enhanced Vegetation Index (EVI) and the Photochemical Reflectance Index (PRI) detected the drought effect, but the PRI only after normalization for absorbed light. These results were compared to a two other forests where a severe drought event had affected GPP and these data confirmed that especially the PRI normalized for absorbed light provides useful information about vegetation functioning that is not captured by other remote sensing indicators under test.
Torgasheva, Anna A; Rubtsov, Nikolai B; Borodin, Pavel M
2013-03-01
Homologous chromosome synapsis in inversion heterozygotes results in the formation of inversion loops. These loops might be transformed into straight, non-homologously paired bivalents via synaptic adjustment. Synaptic adjustment was discovered 30 years ago; however, its relationship with recombination has remained unclear. We analysed this relationship in female mouse embryos heterozygous for large paracentric inversion In(1)1Rk using immunolocalisation of the synaptonemal complex (SYCP3) and mature recombination nodules (MLH1) proteins. The frequency of cells containing bivalents with inversion loops decreased from 69 % to 28 % during pachytene. If an MLH1 focus was present in the non-homologously paired inverted region of the straight bivalent, it was always located in the middle of the inversion. Most of the small, incompletely adjusted loops contained MLH1 foci near the points at which pairing partners were switched. This observation indicates that the degree of synaptic adjustment depended on the crossover position. Complete synaptic adjustment was only possible if a crossover (CO) was located exactly in the middle of the inversion. If a CO was located at any other site, this interrupted synaptic adjustment and resulted in inversion loops of different sizes with an MLH1 focus at or near the edge of the remaining loop.
Group extraction of organic compounds present in liquid samples
NASA Technical Reports Server (NTRS)
Jahnsen, Vilhelm J. (Inventor)
1976-01-01
An extraction device is disclosed comprising a tube containing a substantially inert, chemically non-reactive packing material with a large surface area to volume ratio. A sample which consists of organic compounds dissolved in a liquid, is introduced into the tube. As the sample passes through the packing material it spreads over the material's large surface area to form a thin liquid film which is held on the packing material in a stationary state. A particular group or family of compounds is extractable from the sample by passing a particular solvent system consisting of a solvent and selected reagents through the packing material. The reagents cause optimum conditions to exist for the compounds of the particular family to pass through the phase boundary between the sample liquid and the solvent of the solvent system. Thus, the compounds of the particular family are separated from the sample liquid and become dissolved in the solvent of the solvent system. The particular family of compounds dissolved in the solvent, representing an extract, exits the tube together with the solvent through the tube's nozzle, while the rest of the sample remains on the packing material in a stationary state. Subsequently, a different solvent system may be passed through the packing material to extract another family of compounds from the remaining sample on the packing material.
Hayashi, Paul H
2016-02-04
Hepatotoxicity due to drugs, herbal or dietary supplements remains largely a clinical diagnosis based on meticulous history taking and exclusion of other causes of liver injury. In 2004, the U.S. Drug-Induced Liver Injury Network (DILIN) was created under the auspices of the U.S. National Institute of Diabetes and Digestive and Kidney Diseases with the aims of establishing a large registry of cases for clinical, epidemiological and mechanistic study. From inception, the DILIN has used an expert opinion process that incorporates consensus amongst three different DILIN hepatologists assigned to each case. It is the most well-established, well-described and vigorous expert opinion process for DILI to date, and yet it is an imperfect standard. This review will discuss the DILIN expert opinion process, its strengths and weaknesses, psychometric performance and future.
Quantifying the uncertainty in heritability.
Furlotte, Nicholas A; Heckerman, David; Lippert, Christoph
2014-05-01
The use of mixed models to determine narrow-sense heritability and related quantities such as SNP heritability has received much recent attention. Less attention has been paid to the inherent variability in these estimates. One approach for quantifying variability in estimates of heritability is a frequentist approach, in which heritability is estimated using maximum likelihood and its variance is quantified through an asymptotic normal approximation. An alternative approach is to quantify the uncertainty in heritability through its Bayesian posterior distribution. In this paper, we develop the latter approach, make it computationally efficient and compare it to the frequentist approach. We show theoretically that, for a sufficiently large sample size and intermediate values of heritability, the two approaches provide similar results. Using the Atherosclerosis Risk in Communities cohort, we show empirically that the two approaches can give different results and that the variance/uncertainty can remain large.
Factors modifying the response of large animals to low-intensity radiation exposure
NASA Technical Reports Server (NTRS)
Page, N. P.; Still, E. T.
1972-01-01
In assessing the biological response to space radiation, two of the most important modifying factors are dose protraction and dose distribution to the body. Studies are reported in which sheep and swine were used to compare the hematology and lethality response resulting from radiation exposure encountered in a variety of forms, including acute (high dose-rate), chronic (low dose-rate), combinations of acute and chronic, and whether received as a continuous or as fractionated exposure. While sheep and swine are basically similar in response to acute radiation, their sensitivity to chronic irradiation is markedly different. Sheep remain relatively sensitive as the radiation exposure is protracted while swine are more resistant and capable of surviving extremely large doses of chronic irradiation. This response to chronic irradiation correlated well with changes in radiosensitivity and recovery following an acute, sublethal exposure.
Dodge, Somayeh; Bohrer, Gil; Weinzierl, Rolf P.; Davidson, Sarah C.; Kays, Roland; Douglas, David C.; Cruz, Sebastian; Han, J.; Brandes, David; Wikelski, Martin
2013-01-01
The movement of animals is strongly influenced by external factors in their surrounding environment such as weather, habitat types, and human land use. With advances in positioning and sensor technologies, it is now possible to capture animal locations at high spatial and temporal granularities. Likewise, scientists have an increasing access to large volumes of environmental data. Environmental data are heterogeneous in source and format, and are usually obtained at different spatiotemporal scales than movement data. Indeed, there remain scientific and technical challenges in developing linkages between the growing collections of animal movement data and the large repositories of heterogeneous remote sensing observations, as well as in the developments of new statistical and computational methods for the analysis of movement in its environmental context. These challenges include retrieval, indexing, efficient storage, data integration, and analytical techniques.
NASA Technical Reports Server (NTRS)
Weinan, E.; Shu, Chi-Wang
1994-01-01
High order essentially non-oscillatory (ENO) schemes, originally designed for compressible flow and in general for hyperbolic conservation laws, are applied to incompressible Euler and Navier-Stokes equations with periodic boundary conditions. The projection to divergence-free velocity fields is achieved by fourth-order central differences through fast Fourier transforms (FFT) and a mild high-order filtering. The objective of this work is to assess the resolution of ENO schemes for large scale features of the flow when a coarse grid is used and small scale features of the flow, such as shears and roll-ups, are not fully resolved. It is found that high-order ENO schemes remain stable under such situations and quantities related to large scale features, such as the total circulation around the roll-up region, are adequately resolved.
NASA Technical Reports Server (NTRS)
Weinan, E.; Shu, Chi-Wang
1992-01-01
High order essentially non-oscillatory (ENO) schemes, originally designed for compressible flow and in general for hyperbolic conservation laws, are applied to incompressible Euler and Navier-Stokes equations with periodic boundary conditions. The projection to divergence-free velocity fields is achieved by fourth order central differences through Fast Fourier Transforms (FFT) and a mild high-order filtering. The objective of this work is to assess the resolution of ENO schemes for large scale features of the flow when a coarse grid is used and small scale features of the flow, such as shears and roll-ups, are not fully resolved. It is found that high-order ENO schemes remain stable under such situations and quantities related to large-scale features, such as the total circulation around the roll-up region, are adequately resolved.
Coherent structures: Comments on mechanisms
NASA Technical Reports Server (NTRS)
Hunt, J. C. R.
1987-01-01
There is now overwhelming evidence that in most turbulent flows there exist regions moving with the flow where the velocity and vorticity have a characteristic structure. These regions are called coherent structures because within them the large-scale distributions of velocity and/or vorticity remain coherent even as these structures move through the flow and interact with other structures. Since the flow enters and leaves the bounding surfaces of these structures, a useful definition for coherent structures is that they are open volumes with distinctive large-scale vorticity distributions. Possible fruitful directions for the study of the dynamics of coherent structures are suggested. Most coherent structures research to data was concentrated on measurement and kinematical analysis; there is now a welcome move to examine the dynamics of coherent structures, by a variety of different methods. A few of them will be described.
Individual differences in non-verbal number acuity correlate with maths achievement.
Halberda, Justin; Mazzocco, Michèle M M; Feigenson, Lisa
2008-10-02
Human mathematical competence emerges from two representational systems. Competence in some domains of mathematics, such as calculus, relies on symbolic representations that are unique to humans who have undergone explicit teaching. More basic numerical intuitions are supported by an evolutionarily ancient approximate number system that is shared by adults, infants and non-human animals-these groups can all represent the approximate number of items in visual or auditory arrays without verbally counting, and use this capacity to guide everyday behaviour such as foraging. Despite the widespread nature of the approximate number system both across species and across development, it is not known whether some individuals have a more precise non-verbal 'number sense' than others. Furthermore, the extent to which this system interfaces with the formal, symbolic maths abilities that humans acquire by explicit instruction remains unknown. Here we show that there are large individual differences in the non-verbal approximation abilities of 14-year-old children, and that these individual differences in the present correlate with children's past scores on standardized maths achievement tests, extending all the way back to kindergarten. Moreover, this correlation remains significant when controlling for individual differences in other cognitive and performance factors. Our results show that individual differences in achievement in school mathematics are related to individual differences in the acuity of an evolutionarily ancient, unlearned approximate number sense. Further research will determine whether early differences in number sense acuity affect later maths learning, whether maths education enhances number sense acuity, and the extent to which tertiary factors can affect both.
Linking behavioural syndromes and cognition: a behavioural ecology perspective.
Sih, Andrew; Del Giudice, Marco
2012-10-05
With the exception of a few model species, individual differences in cognition remain relatively unstudied in non-human animals. One intriguing possibility is that variation in cognition is functionally related to variation in personality. Here, we review some examples and present hypotheses on relationships between personality (or behavioural syndromes) and individual differences in cognitive style. Our hypotheses are based largely on a connection between fast-slow behavioural types (BTs; e.g. boldness, aggressiveness, exploration tendency) and cognitive speed-accuracy trade-offs. We also discuss connections between BTs, cognition and ecologically important aspects of decision-making, including sampling, impulsivity, risk sensitivity and choosiness. Finally, we introduce the notion of cognition syndromes, and apply ideas from theories on adaptive behavioural syndromes to generate predictions on cognition syndromes.
Braithwaite, J; Hindle, D; Phelan, P D; Hanson, R
1998-06-01
Casemix funding for hospitals with the use of diagnosis-related groups (DRGs), which organise patients' conditions into similar clinical categories with similar costs, was introduced in Australia five years ago. It has been applied in different ways and to a greater or lesser extent in different Australian States. Only Victoria and South Australia have implemented casemix funding across all healthcare services. Attempts have been made to formally evaluate its impact, but they have not met the required scientific standards in controlling for confounding factors. Casemix funding remains a much-discussed issue. In this Debate, Braithwaite and Hindle take a contrary position, largely to stimulate policy debate; Phelan defends the casemix concept and advocates retaining its best features; and Hanson adds a plea for consumer input.
Recent progress in multi-electrode spike sorting methods
Lefebvre, Baptiste; Yger, Pierre; Marre, Olivier
2017-01-01
In recent years, arrays of extracellular electrodes have been developed and manufactured to record simultaneously from hundreds of electrodes packed with a high density. These recordings should allow neuroscientists to reconstruct the individual activity of the neurons spiking in the vicinity of these electrodes, with the help of signal processing algorithms. Algorithms need to solve a source separation problem, also known as spike sorting. However, these new devices challenge the classical way to do spike sorting. Here we review different methods that have been developed to sort spikes from these large-scale recordings. We describe the common properties of these algorithms, as well as their main differences. Finally, we outline the issues that remain to be solved by future spike sorting algorithms. PMID:28263793
Prospects for generating electricity by large onshore and offshore wind farms
NASA Astrophysics Data System (ADS)
Volker, Patrick J. H.; Hahmann, Andrea N.; Badger, Jake; Jørgensen, Hans E.
2017-03-01
The decarbonisation of energy sources requires additional investments in renewable technologies, including the installation of onshore and offshore wind farms. For wind energy to remain competitive, wind farms must continue to provide low-cost power even when covering larger areas. Inside very large wind farms, winds can decrease considerably from their free-stream values to a point where an equilibrium wind speed is reached. The magnitude of this equilibrium wind speed is primarily dependent on the balance between turbine drag force and the downward momentum influx from above the wind farm. We have simulated for neutral atmospheric conditions, the wind speed field inside different wind farms that range from small (25 km2) to very large (105 km2) in three regions with distinct wind speed and roughness conditions. Our results show that the power density of very large wind farms depends on the local free-stream wind speed, the surface characteristics, and the turbine density. In onshore regions with moderate winds the power density of very large wind farms reaches 1 W m-2, whereas in offshore regions with very strong winds it exceeds 3 W m-2. Despite a relatively low power density, onshore regions with moderate winds offer potential locations for very large wind farms. In offshore regions, clusters of smaller wind farms are generally preferable; under very strong winds also very large offshore wind farms become efficient.
Vorticity Transfer in Shock Wave Interactions with Turbulence and Vortices
NASA Astrophysics Data System (ADS)
Agui, J. H.; Andreopoulos, J.
1998-11-01
Time-dependent, three-dimensional vorticity measurements of shock waves interacting with grid generated turbulence and concentrated tip vortices were conducted in a large diameter shock tube facility. Two different mesh size grids and a NACA-0012 semi-span wing acting as a tip vortex generator were used to carry out different relative Mach number interactions. The turbulence interactions produced a clear amplification of the lateral and spanwise vorticity rms, while the longitudinal component remained mostly unaffected. By comparison, the tip vortex/shock wave interactions produced a two fold increase in the rms of longitudinal vorticity. Considerable attention was given to the vorticity source terms. The mean and rms of the vorticity stretching terms dominated by 5 to 7 orders of magnitude over the dilitational compression terms in all the interactions. All three signals of the stretching terms manifested very intermittent, large amplitude peak events which indicated the bursting character of the stretching process. Distributions of these signals were characterized by extremely large levels of flatness with varying degrees of skewness. These distribution patterns were found to change only slightly through the turbulence interactions. However, the tip vortex/shock wave interactions brought about significant changes in these distributions which were associated with the abrupt structural changes of the vortex after the interaction.
Surveillance of Nicotine and pH in Cigarette and Cigar Filler
Lawler, Tameka S.; Stanfill, Stephen B.; deCastro, B. Rey; Lisko, Joseph G.; Duncan, Bryce W.; Richter, Patricia; Watson, Clifford H.
2017-01-01
Objective We examined differences between nicotine concentrations and pH in cigarette and cigar tobacco filler. Methods Nicotine and pH levels for 50 cigarette and 75 cigar brands were measured. Non-mentholated and mentholated cigarette products were included in the analysis along with several cigar types as identified by the manufacturer: large cigars, pipe tobacco cigars, cigarillos, mini cigarillos, and little cigars. Results There were significant differences found between pH and nicotine for cigarette and cigar tobacco products. Mean nicotine concentrations in cigarettes (19.2 mg/g) and large cigars (15.4 mg/g) were higher than the other cigars types, especially the pipe tobacco cigars (8.79 mg/g). The mean pH for cigarettes was pH 5.46. Large cigars had the highest mean pH value (pH 6.10) and pipe tobacco cigars had the lowest (pH 5.05). Conclusions Although cigarettes are the most common combustible tobacco product used worldwide, cigar use remains popular. Our research provides a means to investigate the possibility of distinguishing the 2 tobacco product types and offers information on nicotine and pH across a wide range of cigarette and cigar varieties that may be beneficial to help establish tobacco policies and regulations across product types. PMID:28989950
Wodtke, Geoffrey T.
2016-01-01
This study outlines a theory of social class based on workplace ownership and authority relations, and it investigates the link between social class and growth in personal income inequality since the 1980s. Inequality trends are governed by changes in between-class income differences, changes in the relative size of different classes, and changes in within-class income dispersion. Data from the General Social Survey are used to investigate each of these changes in turn and to evaluate their impact on growth in inequality at the population level. Results indicate that between-class income differences grew by about 60 percent since the 1980s and that the relative size of different classes remained fairly stable. A formal decomposition analysis indicates that changes in the relative size of different social classes had a small dampening effect and that growth in between-class income differences had a large inflationary effect on trends in personal income inequality. PMID:27087695
Wodtke, Geoffrey T
2016-03-01
This study outlines a theory of social class based on workplace ownership and authority relations, and it investigates the link between social class and growth in personal income inequality since the 1980s. Inequality trends are governed by changes in between-class income differences, changes in the relative size of different classes, and changes in within-class income dispersion. Data from the General Social Survey are used to investigate each of these changes in turn and to evaluate their impact on growth in inequality at the population level. Results indicate that between-class income differences grew by about 60% since the 1980s and that the relative size of different classes remained fairly stable. A formal decomposition analysis indicates that changes in the relative size of different social classes had a small dampening effect and that growth in between-class income differences had a large inflationary effect on trends in personal income inequality.
Insect succession on remains of human and animals in Shenzhen, China.
Wang, Yu; Ma, Meng-Yun; Jiang, Xin-Yu; Wang, Jiang-Feng; Li, Liang-Liang; Yin, Xiao-Jun; Wang, Min; Lai, Yue; Tao, Lu-Yang
2017-02-01
Most forensic entomological succession studies have been carried out using pig or rabbit carcasses; however, there have been few studies on the differences between insect succession patterns on human cadavers and on animal carcasses. In order to clarify the differences between decomposition and insect succession patterns of human cadavers and animal carcasses, one 49.5kg human cadaver, two large pig carcasses (45 and 48kg), two small pig carcasses (23 and 25kg) and two rabbit carcasses (both 1.75kg) were placed in the same field conditions in Shenzhen, China for a comparative study on August, 2013. The results indicated that: (1) The duration from fresh to skeletonization is in order of human cadaver>large pig carcasses>small pig carcasses>rabbit carcasses; (2) insect assemblages (including developmental stages) are more complex on larger carcasses, in order of human cadaver=large pig carcasses>small pig carcasses>rabbit carcasses; (3) the developmental rates of the same forensically important fly species on all carcasses are consistent; (4) all identified species of Calliphoridae can complete development of one generation on human cadaver, and both large and small pig carcasses, while on rabbit carcasses, only a subset of the Calliphoridae species can finish development of one generation; (5) beetles can generate offspring on human cadaver, and both large and small pig carcasses, while they do not generate offspring on rabbit carcasses. This study provides useful comparative data for decomposition and insect succession pattern of human cadaver with animal carcasses. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Meridional flow in the solar convection zone. I. Measurements from gong data
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kholikov, S.; Serebryanskiy, A.; Jackiewicz, J., E-mail: kholikov@noao.edu
2014-04-01
Large-scale plasma flows in the Sun's convection zone likely play a major role in solar dynamics on decadal timescales. In particular, quantifying meridional motions is a critical ingredient for understanding the solar cycle and the transport of magnetic flux. Because the signal of such features can be quite small in deep solar layers and be buried in systematics or noise, the true meridional velocity profile has remained elusive. We perform time-distance helioseismology measurements on several years worth of Global Oscillation Network Group Doppler data. A spherical harmonic decomposition technique is applied to a subset of acoustic modes to measure travel-timemore » differences to try to obtain signatures of meridional flows throughout the solar convection zone. Center-to-limb systematics are taken into account in an intuitive yet ad hoc manner. Travel-time differences near the surface that are consistent with a poleward flow in each hemisphere and are similar to previous work are measured. Additionally, measurements in deep layers near the base of the convection zone suggest a possible equatorward flow, as well as partial evidence of a sign change in the travel-time differences at mid-convection zone depths. This analysis on an independent data set using different measurement techniques strengthens recent conclusions that the convection zone may have multiple 'cells' of meridional flow. The results may challenge the common understanding of one large conveyor belt operating in the solar convection zone. Further work with helioseismic inversions and a careful study of systematic effects are needed before firm conclusions of these large-scale flow structures can be made.« less
Aircraft-type dependency of contrail evolution
NASA Astrophysics Data System (ADS)
Unterstrasser, S.; Görsch, N.
2014-12-01
The impact of aircraft type on contrail evolution is assessed using a large eddy simulation model with Lagrangian ice microphysics. Six different aircraft ranging from the small regional airliner Bombardier CRJ to the largest aircraft Airbus A380 are taken into account. Differences in wake vortex properties and fuel flow lead to considerable variations in the early contrail geometric depth and ice crystal number. Larger aircraft produce contrails with more ice crystals (assuming that the number of initially generated ice crystals per kilogram fuel is constant). These initial differences are reduced in the first minutes, as the ice crystal loss during the vortex phase is stronger for larger aircraft. In supersaturated air, contrails of large aircraft are much deeper after 5 min than those of small aircraft. A parameterization for the final vertical displacement of the wake vortex system is provided, depending only on the initial vortex circulation and stratification. Cloud resolving simulations are used to examine whether the aircraft-induced initial differences have a long-lasting mark. These simulations suggest that the synoptic scenario controls the contrail cirrus evolution qualitatively. However, quantitative differences between the contrail cirrus properties of the various aircraft remain over the total simulation period of 6 h. The total extinctions of A380-produced contrails are about 1.5 to 2.5 times higher than those from contrails of a Bombardier CRJ.
Evaluation of two-phase flow solvers using Level Set and Volume of Fluid methods
NASA Astrophysics Data System (ADS)
Bilger, C.; Aboukhedr, M.; Vogiatzaki, K.; Cant, R. S.
2017-09-01
Two principal methods have been used to simulate the evolution of two-phase immiscible flows of liquid and gas separated by an interface. These are the Level-Set (LS) method and the Volume of Fluid (VoF) method. Both methods attempt to represent the very sharp interface between the phases and to deal with the large jumps in physical properties associated with it. Both methods have their own strengths and weaknesses. For example, the VoF method is known to be prone to excessive numerical diffusion, while the basic LS method has some difficulty in conserving mass. Major progress has been made in remedying these deficiencies, and both methods have now reached a high level of physical accuracy. Nevertheless, there remains an issue, in that each of these methods has been developed by different research groups, using different codes and most importantly the implementations have been fine tuned to tackle different applications. Thus, it remains unclear what are the remaining advantages and drawbacks of each method relative to the other, and what might be the optimal way to unify them. In this paper, we address this gap by performing a direct comparison of two current state-of-the-art variations of these methods (LS: RCLSFoam and VoF: interPore) and implemented in the same code (OpenFoam). We subject both methods to a pair of benchmark test cases while using the same numerical meshes to examine a) the accuracy of curvature representation, b) the effect of tuning parameters, c) the ability to minimise spurious velocities and d) the ability to tackle fluids with very different densities. For each method, one of the test cases is chosen to be fairly benign while the other test case is expected to present a greater challenge. The results indicate that both methods can be made to work well on both test cases, while displaying different sensitivity to the relevant parameters.
1982-02-01
suggests their use as cooking vessels. An analysis of the faunal remains indicates that deer was the primary large namal exploited; turtle remains are...identified include deer (64.4%), turtle (14.3%), jackrabbit (14.3%) and an unidentified large bird (7%). The Paleoindian materials recovered from the...prehistoric archeologi- cal sites within this area and the cultural adaptations which they rep- resent are neither too limited in nature nor too nebulous to be
Markov modeling of peptide folding in the presence of protein crowders
NASA Astrophysics Data System (ADS)
Nilsson, Daniel; Mohanty, Sandipan; Irbäck, Anders
2018-02-01
We use Markov state models (MSMs) to analyze the dynamics of a β-hairpin-forming peptide in Monte Carlo (MC) simulations with interacting protein crowders, for two different types of crowder proteins [bovine pancreatic trypsin inhibitor (BPTI) and GB1]. In these systems, at the temperature used, the peptide can be folded or unfolded and bound or unbound to crowder molecules. Four or five major free-energy minima can be identified. To estimate the dominant MC relaxation times of the peptide, we build MSMs using a range of different time resolutions or lag times. We show that stable relaxation-time estimates can be obtained from the MSM eigenfunctions through fits to autocorrelation data. The eigenfunctions remain sufficiently accurate to permit stable relaxation-time estimation down to small lag times, at which point simple estimates based on the corresponding eigenvalues have large systematic uncertainties. The presence of the crowders has a stabilizing effect on the peptide, especially with BPTI crowders, which can be attributed to a reduced unfolding rate ku, while the folding rate kf is left largely unchanged.
NASA Astrophysics Data System (ADS)
Vermeulen, A.; Verheggen, B.; Pieterse, G.; Haszpra, L.
2007-12-01
Tall towers allow us to observe the integrated influence of carbon exchange processes from large areas on the concentrations of CO2. The signal received shows a large variability at diurnal and synoptic timescales. The question remains how high resolutions and how accurate transport models need to be, in order to discriminate the relevant source terms from the atmospheric signal. We will examine the influence of the resolution of (ECMWF) meteorological fields, antropogenic and biogenic fluxes when going from resolutions of 2° to 0.2° lat-lon, using a simple Lagrangian 2D transport model. Model results will be compared to other Eulerian model results and observations at the CHIOTTO/CarboEurope tall tower network in Europe. Biogenic fluxes taken into account are from the FACEM model (Pieterse et al, 2006). Results show that the relative influence of the different CO2 exchange processes is very different at each tower and that higher model resolution clearly pays off in better model performance.
Huang, Chun; Zhang, Jin; Young, Neil P; Snaith, Henry J; Grant, Patrick S
2016-05-10
Supercapacitors are in demand for short-term electrical charge and discharge applications. Unlike conventional supercapacitors, solid-state versions have no liquid electrolyte and do not require robust, rigid packaging for containment. Consequently they can be thinner, lighter and more flexible. However, solid-state supercapacitors suffer from lower power density and where new materials have been developed to improve performance, there remains a gap between promising laboratory results that usually require nano-structured materials and fine-scale processing approaches, and current manufacturing technology that operates at large scale. We demonstrate a new, scalable capability to produce discrete, multi-layered electrodes with a different material and/or morphology in each layer, and where each layer plays a different, critical role in enhancing the dynamics of charge/discharge. This layered structure allows efficient utilisation of each material and enables conservative use of hard-to-obtain materials. The layered electrode shows amongst the highest combinations of energy and power densities for solid-state supercapacitors. Our functional design and spray manufacturing approach to heterogeneous electrodes provide a new way forward for improved energy storage devices.
What Googling Trends Tell Us About Public Interest in Earthquakes
NASA Astrophysics Data System (ADS)
Tan, Y. J.; Maharjan, R.
2017-12-01
Previous studies have shown that immediately after large earthquakes, there is a period of increased public interest. This represents a window of opportunity for science communication and disaster relief fundraising efforts to reach more people. However, how public interest varies for different earthquakes has not been quantified systematically on a global scale. We analyze how global search interest for the term "earthquake" on Google varies following earthquakes of magnitude ≥ 5.5 from 2004 to 2016. We find that there is a spike in search interest after large earthquakes followed by an exponential temporal decay. Preliminary results suggest that the period of increased search interest scales with death toll and correlates with the period of increased media coverage. This suggests that the relationship between the period of increased public interest in earthquakes and death toll might be an effect of differences in media coverage. However, public interest never remains elevated for more than three weeks. Therefore, to take advantage of this short period of increased public interest, science communication and disaster relief fundraising efforts have to act promptly following devastating earthquakes.
Host-Specific Adaptation of HIV-1 Subtype B in the Japanese Population
Chikata, Takayuki; Carlson, Jonathan M.; Tamura, Yoshiko; Borghan, Mohamed Ali; Naruto, Takuya; Hashimoto, Masao; Murakoshi, Hayato; Le, Anh Q.; Mallal, Simon; John, Mina; Gatanaga, Hiroyuki; Oka, Shinichi; Brumme, Zabrina L.
2014-01-01
ABSTRACT The extent to which HIV-1 clade B strains exhibit population-specific adaptations to host HLA alleles remains incompletely known, in part due to incomplete characterization of HLA-associated HIV-1 polymorphisms (HLA-APs) in different global populations. Moreover, it remains unknown to what extent the same HLA alleles may drive significantly different escape pathways across populations. As the Japanese population exhibits distinctive HLA class I allele distributions, comparative analysis of HLA-APs between HIV-1 clade B-infected Japanese and non-Asian cohorts could shed light on these questions. However, HLA-APs remain incompletely mapped in Japan. In a cohort of 430 treatment-naive Japanese with chronic HIV-1 clade B infection, we identified 284 HLA-APs in Gag, Pol, and Nef using phylogenetically corrected methods. The number of HLA-associated substitutions in Pol, notably those restricted by HLA-B*52:01, was weakly inversely correlated with the plasma viral load (pVL), suggesting that the transmission and persistence of B*52:01-driven Pol mutations could modulate the pVL. Differential selection of HLA-APs between HLA subtype members, including those differing only with respect to substitutions outside the peptide-binding groove, was observed, meriting further investigation as to their mechanisms of selection. Notably, two-thirds of HLA-APs identified in Japan had not been reported in previous studies of predominantly Caucasian cohorts and were attributable to HLA alleles unique to, or enriched in, Japan. We also identified 71 cases where the same HLA allele drove significantly different escape pathways in Japan versus predominantly Caucasian cohorts. Our results underscore the distinct global evolution of HIV-1 clade B as a result of host population-specific cellular immune pressures. IMPORTANCE Cytotoxic T lymphocyte (CTL) escape mutations in HIV-1 are broadly predictable based on the HLA class I alleles expressed by the host. Because HLA allele distributions differ among worldwide populations, the pattern and diversity of HLA-associated escape mutations are likely to be somewhat distinct to each race and region. HLA-associated polymorphisms (HLA-APs) in HIV-1 have previously been identified at the population level in European, North American, Australian, and African cohorts; however, large-scale analyses of HIV-1 clade B-specific HLA-APs in Asians are lacking. Differential intraclade HIV-1 adaptation to global populations can be investigated via comparative analyses of HLA-associated polymorphisms across ethnic groups, but such studies are rare. Here, we identify HLA-APs in a large Japanese HIV-1 clade B cohort using phylogenetically informed methods and observe that the majority of them had not been previously characterized in predominantly Caucasian populations. The results highlight HIV's unique adaptation to cellular immune pressures imposed by different global populations. PMID:24522911
Host-specific adaptation of HIV-1 subtype B in the Japanese population.
Chikata, Takayuki; Carlson, Jonathan M; Tamura, Yoshiko; Borghan, Mohamed Ali; Naruto, Takuya; Hashimoto, Masao; Murakoshi, Hayato; Le, Anh Q; Mallal, Simon; John, Mina; Gatanaga, Hiroyuki; Oka, Shinichi; Brumme, Zabrina L; Takiguchi, Masafumi
2014-05-01
The extent to which HIV-1 clade B strains exhibit population-specific adaptations to host HLA alleles remains incompletely known, in part due to incomplete characterization of HLA-associated HIV-1 polymorphisms (HLA-APs) in different global populations. Moreover, it remains unknown to what extent the same HLA alleles may drive significantly different escape pathways across populations. As the Japanese population exhibits distinctive HLA class I allele distributions, comparative analysis of HLA-APs between HIV-1 clade B-infected Japanese and non-Asian cohorts could shed light on these questions. However, HLA-APs remain incompletely mapped in Japan. In a cohort of 430 treatment-naive Japanese with chronic HIV-1 clade B infection, we identified 284 HLA-APs in Gag, Pol, and Nef using phylogenetically corrected methods. The number of HLA-associated substitutions in Pol, notably those restricted by HLA-B*52:01, was weakly inversely correlated with the plasma viral load (pVL), suggesting that the transmission and persistence of B*52:01-driven Pol mutations could modulate the pVL. Differential selection of HLA-APs between HLA subtype members, including those differing only with respect to substitutions outside the peptide-binding groove, was observed, meriting further investigation as to their mechanisms of selection. Notably, two-thirds of HLA-APs identified in Japan had not been reported in previous studies of predominantly Caucasian cohorts and were attributable to HLA alleles unique to, or enriched in, Japan. We also identified 71 cases where the same HLA allele drove significantly different escape pathways in Japan versus predominantly Caucasian cohorts. Our results underscore the distinct global evolution of HIV-1 clade B as a result of host population-specific cellular immune pressures. Cytotoxic T lymphocyte (CTL) escape mutations in HIV-1 are broadly predictable based on the HLA class I alleles expressed by the host. Because HLA allele distributions differ among worldwide populations, the pattern and diversity of HLA-associated escape mutations are likely to be somewhat distinct to each race and region. HLA-associated polymorphisms (HLA-APs) in HIV-1 have previously been identified at the population level in European, North American, Australian, and African cohorts; however, large-scale analyses of HIV-1 clade B-specific HLA-APs in Asians are lacking. Differential intraclade HIV-1 adaptation to global populations can be investigated via comparative analyses of HLA-associated polymorphisms across ethnic groups, but such studies are rare. Here, we identify HLA-APs in a large Japanese HIV-1 clade B cohort using phylogenetically informed methods and observe that the majority of them had not been previously characterized in predominantly Caucasian populations. The results highlight HIV's unique adaptation to cellular immune pressures imposed by different global populations.
Controllability of multiplex, multi-time-scale networks
NASA Astrophysics Data System (ADS)
Pósfai, Márton; Gao, Jianxi; Cornelius, Sean P.; Barabási, Albert-László; D'Souza, Raissa M.
2016-09-01
The paradigm of layered networks is used to describe many real-world systems, from biological networks to social organizations and transportation systems. While recently there has been much progress in understanding the general properties of multilayer networks, our understanding of how to control such systems remains limited. One fundamental aspect that makes this endeavor challenging is that each layer can operate at a different time scale; thus, we cannot directly apply standard ideas from structural control theory of individual networks. Here we address the problem of controlling multilayer and multi-time-scale networks focusing on two-layer multiplex networks with one-to-one interlayer coupling. We investigate the practically relevant case when the control signal is applied to the nodes of one layer. We develop a theory based on disjoint path covers to determine the minimum number of inputs (Ni) necessary for full control. We show that if both layers operate on the same time scale, then the network structure of both layers equally affect controllability. In the presence of time-scale separation, controllability is enhanced if the controller interacts with the faster layer: Ni decreases as the time-scale difference increases up to a critical time-scale difference, above which Ni remains constant and is completely determined by the faster layer. We show that the critical time-scale difference is large if layer I is easy and layer II is hard to control in isolation. In contrast, control becomes increasingly difficult if the controller interacts with the layer operating on the slower time scale and increasing time-scale separation leads to increased Ni, again up to a critical value, above which Ni still depends on the structure of both layers. This critical value is largely determined by the longest path in the faster layer that does not involve cycles. By identifying the underlying mechanisms that connect time-scale difference and controllability for a simplified model, we provide crucial insight into disentangling how our ability to control real interacting complex systems is affected by a variety of sources of complexity.
Calcite-accumulating large sulfur bacteria of the genus Achromatium in Sippewissett Salt Marsh
Salman, Verena; Yang, Tingting; Berben, Tom; Klein, Frieder; Angert, Esther; Teske, Andreas
2015-01-01
Large sulfur bacteria of the genus Achromatium are exceptional among Bacteria and Archaea as they can accumulate high amounts of internal calcite. Although known for more than 100 years, they remain uncultured, and only freshwater populations have been studied so far. Here we investigate a marine population of calcite-accumulating bacteria that is primarily found at the sediment surface of tide pools in a salt marsh, where high sulfide concentrations meet oversaturated oxygen concentrations during the day. Dynamic sulfur cycling by phototrophic sulfide-oxidizing and heterotrophic sulfate-reducing bacteria co-occurring in these sediments creates a highly sulfidic environment that we propose induces behavioral differences in the Achromatium population compared with reported migration patterns in a low-sulfide environment. Fluctuating intracellular calcium/sulfur ratios at different depths and times of day indicate a biochemical reaction of the salt marsh Achromatium to diurnal changes in sedimentary redox conditions. We correlate this calcite dynamic with new evidence regarding its formation/mobilization and suggest general implications as well as a possible biological function of calcite accumulation in large bacteria in the sediment environment that is governed by gradients. Finally, we propose a new taxonomic classification of the salt marsh Achromatium based on their adaptation to a significantly different habitat than their freshwater relatives, as indicated by their differential behavior as well as phylogenetic distance on 16S ribosomal RNA gene level. In future studies, whole-genome characterization and additional ecophysiological factors could further support the distinctive position of salt marsh Achromatium. PMID:25909974
Kaitaniemi, Pekka
2008-04-09
Allometric equations are widely used in many branches of biological science. The potential information content of the normalization constant b in allometric equations of the form Y = bX(a) has, however, remained largely neglected. To demonstrate the potential for utilizing this information, I generated a large number of artificial datasets that resembled those that are frequently encountered in biological studies, i.e., relatively small samples including measurement error or uncontrolled variation. The value of X was allowed to vary randomly within the limits describing different data ranges, and a was set to a fixed theoretical value. The constant b was set to a range of values describing the effect of a continuous environmental variable. In addition, a normally distributed random error was added to the values of both X and Y. Two different approaches were then used to model the data. The traditional approach estimated both a and b using a regression model, whereas an alternative approach set the exponent a at its theoretical value and only estimated the value of b. Both approaches produced virtually the same model fit with less than 0.3% difference in the coefficient of determination. Only the alternative approach was able to precisely reproduce the effect of the environmental variable, which was largely lost among noise variation when using the traditional approach. The results show how the value of b can be used as a source of valuable biological information if an appropriate regression model is selected.
Révész, Ágnes; Rokob, Tibor András; Jeanne Dit Fouque, Dany; Turiák, Lilla; Memboeuf, Antony; Vékey, Károly; Drahos, László
2018-05-04
Collision energy is a key parameter determining the information content of beam-type collision induced dissociation tandem mass spectrometry (MS/MS) spectra, and its optimal choice largely affects successful peptide and protein identification in MS-based proteomics. For an MS/MS spectrum, quality of peptide match based on sequence database search, often characterized in terms of a single score, is a complex function of spectrum characteristics, and its collision energy dependence has remained largely unexplored. We carried out electrospray ionization-quadrupole-time of flight (ESI-Q-TOF)-MS/MS measurements on 2807 peptides from tryptic digests of HeLa and E. coli at 21 different collision energies. Agglomerative clustering of the resulting Mascot score versus energy curves revealed that only few of them display a single, well-defined maximum; rather, they feature either a broad plateau or two clear peaks. Nonlinear least-squares fitting of one or two Gaussian functions allowed the characteristic energies to be determined. We found that the double peaks and the plateaus in Mascot score can be associated with the different energy dependence of b- and y-type fragment ion intensities. We determined that the energies for optimum Mascot scores follow separate linear trends for the unimodal and bimodal cases with rather large residual variance even after differences in proton mobility are taken into account. This leaves room for experiment optimization and points to the possible influence of further factors beyond m/ z.
Calcite-accumulating large sulfur bacteria of the genus Achromatium in Sippewissett Salt Marsh.
Salman, Verena; Yang, Tingting; Berben, Tom; Klein, Frieder; Angert, Esther; Teske, Andreas
2015-11-01
Large sulfur bacteria of the genus Achromatium are exceptional among Bacteria and Archaea as they can accumulate high amounts of internal calcite. Although known for more than 100 years, they remain uncultured, and only freshwater populations have been studied so far. Here we investigate a marine population of calcite-accumulating bacteria that is primarily found at the sediment surface of tide pools in a salt marsh, where high sulfide concentrations meet oversaturated oxygen concentrations during the day. Dynamic sulfur cycling by phototrophic sulfide-oxidizing and heterotrophic sulfate-reducing bacteria co-occurring in these sediments creates a highly sulfidic environment that we propose induces behavioral differences in the Achromatium population compared with reported migration patterns in a low-sulfide environment. Fluctuating intracellular calcium/sulfur ratios at different depths and times of day indicate a biochemical reaction of the salt marsh Achromatium to diurnal changes in sedimentary redox conditions. We correlate this calcite dynamic with new evidence regarding its formation/mobilization and suggest general implications as well as a possible biological function of calcite accumulation in large bacteria in the sediment environment that is governed by gradients. Finally, we propose a new taxonomic classification of the salt marsh Achromatium based on their adaptation to a significantly different habitat than their freshwater relatives, as indicated by their differential behavior as well as phylogenetic distance on 16S ribosomal RNA gene level. In future studies, whole-genome characterization and additional ecophysiological factors could further support the distinctive position of salt marsh Achromatium.
Fast and Accurate Simulation of the Cray XMT Multithreaded Supercomputer
DOE Office of Scientific and Technical Information (OSTI.GOV)
Villa, Oreste; Tumeo, Antonino; Secchi, Simone
Irregular applications, such as data mining and analysis or graph-based computations, show unpredictable memory/network access patterns and control structures. Highly multithreaded architectures with large processor counts, like the Cray MTA-1, MTA-2 and XMT, appear to address their requirements better than commodity clusters. However, the research on highly multithreaded systems is currently limited by the lack of adequate architectural simulation infrastructures due to issues such as size of the machines, memory footprint, simulation speed, accuracy and customization. At the same time, Shared-memory MultiProcessors (SMPs) with multi-core processors have become an attractive platform to simulate large scale machines. In this paper, wemore » introduce a cycle-level simulator of the highly multithreaded Cray XMT supercomputer. The simulator runs unmodified XMT applications. We discuss how we tackled the challenges posed by its development, detailing the techniques introduced to make the simulation as fast as possible while maintaining a high accuracy. By mapping XMT processors (ThreadStorm with 128 hardware threads) to host computing cores, the simulation speed remains constant as the number of simulated processors increases, up to the number of available host cores. The simulator supports zero-overhead switching among different accuracy levels at run-time and includes a network model that takes into account contention. On a modern 48-core SMP host, our infrastructure simulates a large set of irregular applications 500 to 2000 times slower than real time when compared to a 128-processor XMT, while remaining within 10\\% of accuracy. Emulation is only from 25 to 200 times slower than real time.« less
Large capacity storage of integrated objects before change blindness.
Landman, Rogier; Spekreijse, Henk; Lamme, Victor A F
2003-01-01
Normal people have a strikingly low ability to detect changes in a visual scene. This has been taken as evidence that the brain represents only a few objects at a time, namely those currently in the focus of attention. In the present study, subjects were asked to detect changes in the orientation of rectangular figures in a textured display across a 1600 ms gray interval. In the first experiment, change detection improved when the location of a possible change was cued during the interval. The cue remained effective during the entire interval, but after the interval, it was ineffective, suggesting that an initially large representation was overwritten by the post-change display. To control for an effect of light intensity during the interval on the decay of the representation, we compared performance with a gray or a white interval screen in a second experiment. We found no difference between these conditions. In the third experiment, attention was occasionally misdirected during the interval by first cueing the wrong figure, before cueing the correct figure. This did not compromise performance compared to a single cue, indicating that when an item is attentionally selected, the representation of yet unchosen items remains available. In the fourth experiment, the cue was shown to be effective when changes in figure size and orientation were randomly mixed. At the time the cue appeared, subjects could not know whether size or orientation would change, therefore these results suggest that the representation contains features in their 'bound' state. Together, these findings indicate that change blindness involves overwriting of a large capacity representation by the post-change display.
Landscape characteristics of disturbed shrubsteppe habitats in southwestern Idaho (USA)
Knick, Steven T.; Rotenberry, J.T.
1997-01-01
We compared 5 zones in shrubsteppe habitats of southwestern Idaho to determine the effect of differing disturbance combinations on landscapes that once shared historically similar disturbance regimes. The primary consequence of agriculture, wildfires, and extensive fires ignited by the military during training activities was loss of native shrubs from the landscape. Agriculture created large square blocks on the landscape, and the landscape contained fewer small patches and more large shrub patches than non-agricultural areas. In contrast, fires left a more fragmented landscape. Repeated fires did not change the distribution of patch sizes, but decreased the total area of remaining shrublands and increased the distance between remaining shrub patches that provide seed sources. Military training with tracked vehicles was associated with a landscape characterized by small, closely spaced, shrub patches. Our results support the general model hypothesized for conversion of shrublands to annual grasslands by disturbance. Larger shrub patches in our region, historically resistant to fire spread and large-scale fires because of a perennial bunchgrass understory, were more fragmented than small patches. Presence of cheatgrass (Bromus tectorum), an exotic annual, was positively related to landscape patchiness and negatively related to number of shrub cells. Thus, cheatgrass dominance can contribute to further fragmentation and loss of the shrub patch by facilitating spread of subsequent fires, carried by continuous fuels, through the patch. The synergistic processes of fragmentation of shrub patches by disturbance, invasion and subsequent dominance by exotic annuals, and fire are converting shrubsteppe in southwestern Idaho to a new state dominated by exotic annual grasslands and high fire frequencies.
A uniform input data convention for the CALL 3-D crash victim simulation
NASA Astrophysics Data System (ADS)
Shaibani, S. J.
1982-07-01
Logical schemes for the labelling of planes (cards D) and functions (cards E) in the input decks used for the Calspan 3-D Crash Victim Simulation (CVS) program are proposed. One benefit of introducing such a standardized format for these inputs would be to facilitate greatly the interchange of data for different vehicles. A further advantage would be that the table of allowed contacts (cards F) could remain largely unaltered. It is hoped that the uniformity of the convention described by these schemes would help to promote the exchange of readily usable data between CVS users.
Migration and Western europe: the old world turning new.
Therborn, G
1987-09-04
The 1960s meant a historical turn of Western Europe, becoming an immigration area. Net immigration has been concentrated to some of the prosperous Western European countries and has been mainly determined by the demand of their particular national labor regimes. The size of alien employment has been very differently affected by the 1973 crisis, but a multiethnical society will remain a novel feature of most Western European countries. Political abdication from full employment and technological change makes a ghetto of un(der)employment a likely prospect of a large part of the second generation of recent immigrants into Western Europe.
Plasma motions in planetary magnetospheres
NASA Technical Reports Server (NTRS)
Hill, T. W.; Dessler, A. J.
1991-01-01
Interplanetary space is pervaded by a supersonic 'solar wind' plasma; five planets, in addition to the earth, have magnetic fields of sufficient strength to form the cometlike cavities called 'magnetospheres'. Comparative studies of these structures have indicated the specific environmental factor that can result in dramatic differences in the behavior of any pair of magnetospheres. Although planetary magnetospheres are large enough to serve as laboratories for in situ study of cosmic plasma and magnetic field behavior effects on particle acceleration and EM emission, much work remains to be done toward relating magnetospheric physics results to the study of remote astrophysical plasmas.
Jupiter Icy Moons Orbiter Mission design overview
NASA Technical Reports Server (NTRS)
Sims, Jon A.
2006-01-01
An overview of the design of a possible mission to three large moons of Jupiter (Callisto, Ganymede, and Europa) is presented. The potential Jupiter Icy Moons Orbiter (JIMO) mission uses ion thrusters powered by a nuclear reactor to transfer from Earth to Jupiter and enter a low-altitude science orbit around each of the moons. The combination of very limited control authority and significant multibody dynamics resulted in some aspects of the trajectory design being different than for any previous mission. The results of several key trades, innovative trajectory types and design processes, and remaining issues are presented.
McDonnell, Patricia; Guttenberg, Abbie; Greenberg, Leonard; Arnett, Ross H.
1986-01-01
Nationwide, 8 percent of all employment-related health plans were self-insured in 1984, which translates into more than 175,000 self-insured plans according to our latest study of independent health plans. The propensity of an organization to self-insure differs primarily by its size, with large establishments more likely to self-insure. In the overwhelming majority of cases, the self-insured benefit was hospital and/or medical. Among employers who self-insure, 23 percent self-administer, and the remaining 77 percent hire a commercial insurance company, Blue Cross/Blue Shield plan, or an independent third-party administrator to administer the health plan. PMID:10312008
A new view on the M 87 jet origin: Turbulent loading leading to large-scale episodic wiggling
NASA Astrophysics Data System (ADS)
Britzen, S.; Fendt, C.; Eckart, A.; Karas, V.
2017-05-01
Context. The nearby, giant radio galaxy M 87 hosts a supermassive black hole (BH) and is well-known for a bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large BH mass, M 87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. Many kinematic studies have been performed to determine the proper motions in the jet. Despite M 87 providing all proofs of being an active BH, the apparent jet speed remained puzzling, because proper motion measurements between 15 and 43 GHz for the same region of 1-10 mas core distance provided largely discrepant results. This source is a prime object to be studied in exquisite detail with the upcoming Event Horizon Telescope (EHT) observations because it promises to allow a direct view on the jet launching process itself. Aims: We aim to decipher some of the kinematic puzzles in the pc-scale jet with the analysis we present here. Methods: We re-modeled and re-analyzed 31 VLBA observations at 15 GHz obtained within the MOJAVE program. The data span a time range between Jul. 1995 and May 2011. We performed a detailed investigation of the pc-scale jet kinematics on different timescales, the shortest periods between the observations beeing 10 and 80 days, and in different jet modes, making use of VLBA observations. In addition, we studied the jet ridge line behavior as a function of time. Special care was taken to analyze the region close to the 15 GHz core, and the dynamics and distribution of newly emerging jet features in the jet. Results: We find an indication for apparent superluminal motion in the jet. Moreover, we present evidence for acceleration between 0.5 and 10 mas of core separation. The data suggest that the central part of M 87 at 15 GHz seems to be rotating. Jet components and counter-jet components are ejected in different directions under varying angles, explaining the impression of a broad opening angle. In this paper we present evidence for two different operating modes of the jet of M 87. The jet switches between two phases: I) the jet ridge line is at least double or the jet axis is displaced vertically, and II) an unperturbed phase where the jet ridge line remains almost straight but is smoothly curved and the jet components are aligned along a classical jet axis. The mode change occurs every couple of years. Between the two operating modes, a transition phase is visible. Conclusions: The M 87 jet visible at 15 GHz probes a different physical zone compared to the standard blazar-zone we tend to see in AGN jets. The most likely scenario explaining the observed phenomena is a turbulent mass loading into the jet, most probably due to local, fast reconnection processes driven by turbulence of a tangled magnetic field, which is either generated in the accretion disk or the disk corona. In addition, on large scales, a global magnetic structure is required to channel the turbulent flow into what evolves into a large-scale jet. Large-scale jet instabilities may explain the curved pattern of the observed jet flow.
NASA Astrophysics Data System (ADS)
Lenderink, Geert; Barbero, Renaud; Loriaux, Jessica; Fowler, Hayley
2017-04-01
Present-day precipitation-temperature scaling relations indicate that hourly precipitation extremes may have a response to warming exceeding the Clausius-Clapeyron (CC) relation; for The Netherlands the dependency on surface dew point temperature follows two times the CC relation corresponding to 14 % per degree. Our hypothesis - as supported by a simple physical argument presented here - is that this 2CC behaviour arises from the physics of convective clouds. So, we think that this response is due to local feedbacks related to the convective activity, while other large scale atmospheric forcing conditions remain similar except for the higher temperature (approximately uniform warming with height) and absolute humidity (corresponding to the assumption of unchanged relative humidity). To test this hypothesis, we analysed the large-scale atmospheric conditions accompanying summertime afternoon precipitation events using surface observations combined with a regional re-analysis for the data in The Netherlands. Events are precipitation measurements clustered in time and space derived from approximately 30 automatic weather stations. The hourly peak intensities of these events again reveal a 2CC scaling with the surface dew point temperature. The temperature excess of moist updrafts initialized at the surface and the maximum cloud depth are clear functions of surface dew point temperature, confirming the key role of surface humidity on convective activity. Almost no differences in relative humidity and the dry temperature lapse rate were found across the dew point temperature range, supporting our theory that 2CC scaling is mainly due to the response of convection to increases in near surface humidity, while other atmospheric conditions remain similar. Additionally, hourly precipitation extremes are on average accompanied by substantial large-scale upward motions and therefore large-scale moisture convergence, which appears to accelerate with surface dew point. This increase in large-scale moisture convergence appears to be consequence of latent heat release due to the convective activity as estimated from the quasi-geostrophic omega equation. Consequently, most hourly extremes occur in precipitation events with considerable spatial extent. Importantly, this event size appears to increase rapidly at the highest dew point temperature range, suggesting potentially strong impacts of climatic warming.
Enhanced integration of large DNA into E. coli chromosome by CRISPR/Cas9.
Chung, Mu-En; Yeh, I-Hsin; Sung, Li-Yu; Wu, Meng-Ying; Chao, Yun-Peng; Ng, I-Son; Hu, Yu-Chen
2017-01-01
Metabolic engineering often necessitates chromosomal integration of multiple genes but integration of large genes into Escherichia coli remains difficult. CRISPR/Cas9 is an RNA-guided system which enables site-specific induction of double strand break (DSB) and programmable genome editing. Here, we hypothesized that CRISPR/Cas9-triggered DSB could enhance homologous recombination and augment integration of large DNA into E. coli chromosome. We demonstrated that CRISPR/Cas9 system was able to trigger DSB in >98% of cells, leading to subsequent cell death, and identified that mutagenic SOS response played roles in the cell survival. By optimizing experimental conditions and combining the λ-Red proteins and linear dsDNA, CRISPR/Cas9-induced DSB enabled homologous recombination of the donor DNA and replacement of lacZ gene in the MG1655 strain at efficiencies up to 99%, and allowed high fidelity, scarless integration of 2.4, 3.9, 5.4, and 7.0 kb DNA at efficiencies approaching 91%, 92%, 71%, and 61%, respectively. The CRISPR/Cas9-assisted gene integration also functioned in different E. coli strains including BL21 (DE3) and W albeit at different efficiencies. Taken together, our methodology facilitated precise integration of dsDNA as large as 7 kb into E. coli with efficiencies exceeding 60%, thus significantly ameliorating the editing efficiency and overcoming the size limit of integration using the commonly adopted recombineering approach. Biotechnol. Bioeng. 2017;114: 172-183. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
NASA Astrophysics Data System (ADS)
Storck, Pascal; Lettenmaier, Dennis P.; Bolton, Susan M.
2002-11-01
The results of a 3 year field study to observe the processes controlling snow interception by forest canopies and under canopy snow accumulation and ablation in mountain maritime climates are reported. The field study was further intended to provide data to develop and test models of forest canopy effects on beneath-canopy snowpack accumulation and melt and the plot and stand scales. Weighing lysimeters, cut-tree experiments, and manual snow surveys were deployed at a site in the Umpqua National Forest, Oregon (elevation 1200 m). A unique design for a weighing lysimeter was employed that allowed continuous measurements of snowpack evolution beneath a forest canopy to be taken at a scale unaffected by variability in canopy throughfall. Continuous observations of snowpack evolution in large clearings were made coincidentally with the canopy measurements. Large differences in snow accumulation and ablation were observed at sites beneath the forest canopy and in large clearings. These differences were not well described by simple relationships between the sites. Over the study period, approximately 60% of snowfall was intercepted by the canopy (up to a maximum of about 40 mm water equivalent). Instantaneous sublimation rates exceeded 0.5 mm per hour for short periods. However, apparent average sublimation from the intercepted snow was less than 1 mm per day and totaled approximately 100 mm per winter season. Approximately 72 and 28% of the remaining intercepted snow was removed as meltwater drip and large snow masses, respectively. Observed differences in snow interception rate and maximum snow interception capacity between Douglas fir (Pseudotsuga menziesii), white fir (Abies concolor), ponderosa pine (Pinus ponderosa), and lodgepole pine (Pinus contorta) were minimal.
Jaakkola, Timo; Wang, John; Yli-Piipari, Sami; Liukkonen, Jarmo
2015-03-01
The purpose of this study was to examine individual- and classroom-level differences in the longitudinal change in motivational regulations during physical education students' transition from elementary (Grade 6) across middle school (Grades 7 to 9). A sample of 757 Finnish adolescents (M = 12.71, SD = 0.23) participated in this study. Participants of the study responded to questionnaires collected six times. A multilevel latent growth modelling approach was used to analyze the data. Results showed that motivational regulations in physical education developed at different rates during middle school. More specifically, students': (a) identified regulation increased across Grades 6 to 9; (b) amotivation increased during middle school transition from Grade 6 to 7; and (c) introjected regulation declined from Grade 8 to 9. Other motivational regulations remained stable across time. The changes in amotivation and introjected regulation were largely due to individual factors, whereas the changes in identified regulation were due to environmental factors. Key pointsStudents' identified regulation increased across Grades 6 to 9.Students' amotivation increased across middle school transition from Grade 6 to 7.Students' introjected regulation declined from Grade 8 to 9.Other motivational regulations remained stable across time.
Jaakkola, Timo; Wang, John; Yli-Piipari, Sami; Liukkonen, Jarmo
2015-01-01
The purpose of this study was to examine individual- and classroom-level differences in the longitudinal change in motivational regulations during physical education students’ transition from elementary (Grade 6) across middle school (Grades 7 to 9). A sample of 757 Finnish adolescents (M = 12.71, SD = 0.23) participated in this study. Participants of the study responded to questionnaires collected six times. A multilevel latent growth modelling approach was used to analyze the data. Results showed that motivational regulations in physical education developed at different rates during middle school. More specifically, students’: (a) identified regulation increased across Grades 6 to 9; (b) amotivation increased during middle school transition from Grade 6 to 7; and (c) introjected regulation declined from Grade 8 to 9. Other motivational regulations remained stable across time. The changes in amotivation and introjected regulation were largely due to individual factors, whereas the changes in identified regulation were due to environmental factors. Key points Students’ identified regulation increased across Grades 6 to 9. Students’ amotivation increased across middle school transition from Grade 6 to 7. Students’ introjected regulation declined from Grade 8 to 9. Other motivational regulations remained stable across time. PMID:25729304
Measuring racial/ethnic disparities across the distribution of health care expenditures.
Cook, Benjamin Lê; Manning, Willard G
2009-10-01
To assess whether black-white and Hispanic-white disparities increase or abate in the upper quantiles of total health care expenditure, conditional on covariates. Nationally representative adult population of non-Hispanic whites, African Americans, and Hispanics from the 2001-2005 Medical Expenditure Panel Surveys. We examine unadjusted racial/ethnic differences across the distribution of expenditures. We apply quantile regression to measure disparities at the median, 75th, 90th, and 95th quantiles, testing for differences over the distribution of health care expenditures and across income and education categories. We test the sensitivity of the results to comparisons based only on health status and estimate a two-part model to ensure that results are not driven by an extremely skewed distribution of expenditures with a large zero mass. Black-white and Hispanic-white disparities diminish in the upper quantiles of expenditure, but expenditures for blacks and Hispanics remain significantly lower than for whites throughout the distribution. For most education and income categories, disparities exist at the median and decline, but remain significant even with increased education and income. Blacks and Hispanics receive significantly disparate care at high expenditure levels, suggesting prioritization of improved access to quality care among minorities with critical health issues.
How do tablet properties influence swallowing behaviours?
Yamamoto, Shinya; Taniguchi, Hiroshige; Hayashi, Hirokazu; Hori, Kazuhiro; Tsujimura, Takanori; Nakamura, Yuki; Sato, Hideaki; Inoue, Makoto
2014-01-01
Behavioural performance of tablet swallowing was evaluated with different tablet conditions in terms of size, number and surface coating. Four different types of tablets were prepared: small or large, and with or without a surface coating. Fourteen normal male adults were instructed to swallow the prepared tablets with 15 ml of water. The number of tablets in one trial was changed from one to three. To evaluate swallowing and tablet transport, electromyographic activity was recorded in the left suprahyoid muscles, and videofluorographic images were examined. All tablet conditions (size, number and surface coating) affected the swallowing performance in terms of total number of swallows, electromyographic burst patterns and location of remaining tablets. Increases in the size and number of tablets increased the number of swallows and electromyographic burst area and duration. In addition, all of these parameters increased while swallowing tablets without a coating compared with tablets with a coating. Location of the remaining tablets was mainly within the mouth. This study only clarified the normal pattern of tablet swallowing under several conditions in healthy subjects, but the results may facilitate comprehensive evaluation and treatment planning in terms of administering medication to dysphagic patients. © 2013 Royal Pharmaceutical Society.
The oblique effect is both allocentric and egocentric
Mikellidou, Kyriaki; Cicchini, Guido Marco; Thompson, Peter G.; Burr, David C.
2016-01-01
Despite continuous movements of the head, humans maintain a stable representation of the visual world, which seems to remain always upright. The mechanisms behind this stability are largely unknown. To gain some insight on how head tilt affects visual perception, we investigate whether a well-known orientation-dependent visual phenomenon, the oblique effect—superior performance for stimuli at cardinal orientations (0° and 90°) compared with oblique orientations (45°)—is anchored in egocentric or allocentric coordinates. To this aim, we measured orientation discrimination thresholds at various orientations for different head positions both in body upright and in supine positions. We report that, in the body upright position, the oblique effect remains anchored in allocentric coordinates irrespective of head position. When lying supine, gravitational effects in the plane orthogonal to gravity are discounted. Under these conditions, the oblique effect was less marked than when upright, and anchored in egocentric coordinates. The results are well explained by a simple “compulsory fusion” model in which the head-based and the gravity-based signals are combined with different weightings (30% and 70%, respectively), even when this leads to reduced sensitivity in orientation discrimination. PMID:26129862
Neurogenesis and Developmental Anesthetic Neurotoxicity
Kang, Eunchai; Berg, Daniel A.; Furmanski, Orion; Jackson, William M.; Ryu, Yun Kyoung; Gray, Christy D.; Mintz, C. David
2017-01-01
The mechanism by which anesthetics might act on the developing brain in order to cause long term deficits remains incompletely understood. The hippocampus has been identified as a structure that is likely to be involved, as rodent models show numerous deficits in behavioral tasks of learning that are hippocampal-dependent. The hippocampus is an unusual structure in that it is the site of large amounts of neurogenesis postnatally, particularly in the first year of life in humans, and these newly generated neurons are critical to the function of this structure. Intriguingly, neurogenesis is a major developmental event that occurs during postulated windows of vulnerability to developmental anesthetic neurotoxicity across the different species in which it has been studied. In this review, we examine the evidence for anesthetic effects on neurogenesis in the early postnatal period and ask whether neurogenesis should be studied further as a putative mechanism of injury. Multiple anesthetics are considered, and both in vivo and in vitro work is presented. While there is abundant evidence that anesthetics act to suppress neurogenesis at several different phases, evidence of a causal link between these effects and any change in learning behavior remains elusive. PMID:27751818
Neurogenesis and developmental anesthetic neurotoxicity.
Kang, Eunchai; Berg, Daniel A; Furmanski, Orion; Jackson, William M; Ryu, Yun Kyoung; Gray, Christy D; Mintz, C David
The mechanism by which anesthetics might act on the developing brain in order to cause long term deficits remains incompletely understood. The hippocampus has been identified as a structure that is likely to be involved, as rodent models show numerous deficits in behavioral tasks of learning that are hippocampal-dependent. The hippocampus is an unusual structure in that it is the site of large amounts of neurogenesis postnatally, particularly in the first year of life in humans, and these newly generated neurons are critical to the function of this structure. Intriguingly, neurogenesis is a major developmental event that occurs during postulated windows of vulnerability to developmental anesthetic neurotoxicity across the different species in which it has been studied. In this review, we examine the evidence for anesthetic effects on neurogenesis in the early postnatal period and ask whether neurogenesis should be studied further as a putative mechanism of injury. Multiple anesthetics are considered, and both in vivo and in vitro work is presented. While there is abundant evidence that anesthetics act to suppress neurogenesis at several different phases, evidence of a causal link between these effects and any change in learning behavior remains elusive. Copyright © 2016. Published by Elsevier Inc.
Guidelines for the recognition of cemetery remains in Greece.
Eliopoulos, Constantine; Moraitis, Konstantinos; Reyes, Federico; Spiliopoulou, Chara; Manolis, Sotiris
2011-06-01
Forensic pathologists frequently consult anthropologists for the identification of skeletonized human remains. These remains may be the result of criminal activity or remains that were unearthed because of erosion, or during construction projects. In some cases, human remains that had been previously buried in a cemetery may be the subject of a forensic investigation. Early recognition of cemetery remains prevents unnecessary efforts and conserves precious resources. One of the key characteristics of cemetery remains is the presence of embalmed tissue. However, there are countries where embalming is not a common practice, and other clues must be sought for identifying previously buried remains. Current funerary customs in Greece and, in particular, the tradition of exhumations result in a large number of misplaced human remains. The present study presents examples of cemetery remains from Greece and offers guidelines for recognizing changes on skeletal remains that may be indicative of a cemetery origin. Location of discovery, condition of the remains, and the types of associated artifacts are all factors that aid forensic anthropologists in identifying cemetery remains.
Wang, Chang; Ren, Qiongqiong; Qin, Xin
2018-01-01
Diffeomorphic demons can guarantee smooth and reversible deformation and avoid unreasonable deformation. However, the number of iterations needs to be set manually, and this greatly influences the registration result. In order to solve this problem, we proposed adaptive diffeomorphic multiresolution demons in this paper. We used an optimized framework with nonrigid registration and diffeomorphism strategy, designed a similarity energy function based on grey value, and stopped iterations adaptively. This method was tested by synthetic image and same modality medical image. Large deformation was simulated by rotational distortion and extrusion transform, medical image registration with large deformation was performed, and quantitative analyses were conducted using the registration evaluation indexes, and the influence of different driving forces and parameters on the registration result was analyzed. The registration results of same modality medical images were compared with those obtained using active demons, additive demons, and diffeomorphic demons. Quantitative analyses showed that the proposed method's normalized cross-correlation coefficient and structural similarity were the highest and mean square error was the lowest. Medical image registration with large deformation could be performed successfully; evaluation indexes remained stable with an increase in deformation strength. The proposed method is effective and robust, and it can be applied to nonrigid registration of same modality medical images with large deformation.
Wang, Chang; Ren, Qiongqiong; Qin, Xin; Yu, Yi
2018-01-01
Diffeomorphic demons can guarantee smooth and reversible deformation and avoid unreasonable deformation. However, the number of iterations needs to be set manually, and this greatly influences the registration result. In order to solve this problem, we proposed adaptive diffeomorphic multiresolution demons in this paper. We used an optimized framework with nonrigid registration and diffeomorphism strategy, designed a similarity energy function based on grey value, and stopped iterations adaptively. This method was tested by synthetic image and same modality medical image. Large deformation was simulated by rotational distortion and extrusion transform, medical image registration with large deformation was performed, and quantitative analyses were conducted using the registration evaluation indexes, and the influence of different driving forces and parameters on the registration result was analyzed. The registration results of same modality medical images were compared with those obtained using active demons, additive demons, and diffeomorphic demons. Quantitative analyses showed that the proposed method's normalized cross-correlation coefficient and structural similarity were the highest and mean square error was the lowest. Medical image registration with large deformation could be performed successfully; evaluation indexes remained stable with an increase in deformation strength. The proposed method is effective and robust, and it can be applied to nonrigid registration of same modality medical images with large deformation.
1979-07-11
Range : 312, 000 kilometers (195,000 miles) This photo of Ganymede (Ice Giant) was taken from Voyager 2 and shows features down to about 5 to 6 kilometers across. Different types of terrain common on Ganymede's surface are visible. The boundary of the largest region of dark ancient terrain on Ganymede can be seen to the east (right), revealing some of the light linear features which may be all that remains of a large ancient impact structure similar to the large ring structure on Callisto. The broad light regions running through the image are the typical grooved structures seen within another example of what might be evidence of large scale lateral motion in Ganymede's crust. The band of grooved terrain (about 100 kilometers wide) in this region appears to be offset by 50 kilometers or more on the left hand edge by a linear feature perpendicular to it. A feature similar to this one was previously discovered by Voyager 1. These are the first clear examples of strike-slip style faulting on any planet other than Earth. Many examples of craters of all ages can be seen in this image, ranging from fresh, bright ray craters to large, subdued circular markings thought to be the 'scars' of large ancient impacts that have been flatteded by glacier-like flows.
Probability based remaining capacity estimation using data-driven and neural network model
NASA Astrophysics Data System (ADS)
Wang, Yujie; Yang, Duo; Zhang, Xu; Chen, Zonghai
2016-05-01
Since large numbers of lithium-ion batteries are composed in pack and the batteries are complex electrochemical devices, their monitoring and safety concerns are key issues for the applications of battery technology. An accurate estimation of battery remaining capacity is crucial for optimization of the vehicle control, preventing battery from over-charging and over-discharging and ensuring the safety during its service life. The remaining capacity estimation of a battery includes the estimation of state-of-charge (SOC) and state-of-energy (SOE). In this work, a probability based adaptive estimator is presented to obtain accurate and reliable estimation results for both SOC and SOE. For the SOC estimation, an n ordered RC equivalent circuit model is employed by combining an electrochemical model to obtain more accurate voltage prediction results. For the SOE estimation, a sliding window neural network model is proposed to investigate the relationship between the terminal voltage and the model inputs. To verify the accuracy and robustness of the proposed model and estimation algorithm, experiments under different dynamic operation current profiles are performed on the commercial 1665130-type lithium-ion batteries. The results illustrate that accurate and robust estimation can be obtained by the proposed method.
Lamarque, Pénélope; Quétier, Fabien; Lavorel, Sandra
2011-05-01
The ecosystem services concept is used in different scientific disciplines and is spreading into policy and business circles to draw attention to the benefits that people receive from biodiversity and ecosystems. However, the concept remains multiform and is used interchangeably with a range of other terms such as ecological, landscape or environmental services. We argue that lexical differences, in fact, result from different understandings of the concept, which could slow its use in nature conservation or sustainable resource use. An application to semi-natural grasslands shows that such differences could lead to very different assessments, of quality, quantity and location of ecosystem services. We argue that a compromise must be found between a broad and simple definition, which is useful for communicating the concept and large-scale policies, and a more refined definition for research and implementation goals such as environmental management and national and international assessments and accounting. Copyright © 2010 Académie des sciences. Published by Elsevier SAS. All rights reserved.
Variation in Age and Size in Fennoscandian Three-Spined Sticklebacks (Gasterosteus aculeatus)
DeFaveri, Jacquelin; Merilä, Juha
2013-01-01
Average age and maximum life span of breeding adult three-spined sticklebacks (Gasterosteus aculeatus) were determined in eight Fennoscandian localities with the aid of skeletochronology. The average age varied from 1.8 to 3.6 years, and maximum life span from three to six years depending on the locality. On average, fish from marine populations were significantly older than those from freshwater populations, but variation within habitat types was large. We also found significant differences in mean body size among different habitat types and populations, but only the population differences remained significant after accounting for variation due to age effects. These results show that generation length and longevity in three-spined sticklebacks can vary significantly from one locality to another, and that population differences in mean body size cannot be explained as a simple consequence of differences in population age structure. We also describe a nanistic population from northern Finland exhibiting long life span and small body size. PMID:24260496
Variation in age and size in Fennoscandian three-spined sticklebacks (Gasterosteus aculeatus).
DeFaveri, Jacquelin; Merilä, Juha
2013-01-01
Average age and maximum life span of breeding adult three-spined sticklebacks (Gasterosteus aculeatus) were determined in eight Fennoscandian localities with the aid of skeletochronology. The average age varied from 1.8 to 3.6 years, and maximum life span from three to six years depending on the locality. On average, fish from marine populations were significantly older than those from freshwater populations, but variation within habitat types was large. We also found significant differences in mean body size among different habitat types and populations, but only the population differences remained significant after accounting for variation due to age effects. These results show that generation length and longevity in three-spined sticklebacks can vary significantly from one locality to another, and that population differences in mean body size cannot be explained as a simple consequence of differences in population age structure. We also describe a nanistic population from northern Finland exhibiting long life span and small body size.
Separating the Influence of Environment from Stress Relaxation Effects on Dwell Fatigue Crack Growth
NASA Technical Reports Server (NTRS)
Telesman, Jack; Gabb, Tim; Ghosn, Louis J.
2016-01-01
Seven different microstructural variations of LSHR were produced by controlling the cooling rate and the subsequent aging and thermal exposure heat treatments. Through cyclic fatigue crack growth testing performed both in air and vacuum, it was established that four out of the seven LSHR heat treatments evaluated, possessed similar intrinsic environmental resistance to cyclic crack growth. For these four heat treatments, it was further shown that the large differences in dwell crack growth behavior which still persisted, were related to their measured stress relaxation behavior. The apparent differences in their dwell crack growth resistance were attributed to the inability of the standard linear elastic fracture mechanics (LEFM) stress intensity parameter to account for visco-plastic behavior. Crack tip stress relaxation controls the magnitude of the remaining local tensile stresses which are directly related to the measured dwell crack growth rates. It was hypothesized that the environmentally weakened grain boundary crack tip regions fail during the dwells when their strength is exceeded by the remaining local crack tip tensile stresses. It was shown that the classical creep crack growth mechanisms such as grain boundary sliding did not contribute to crack growth, but the local visco-plastic behavior still plays a very significant role by determining the crack tip tensile stress field which controls the dwell crack growth behavior. To account for the influence of the visco-plastic behavior on the crack tip stress field, an empirical modification to the LEFM stress intensity parameter, Kmax, was developed by incorporating into the formulation the remaining stress level concept as measured by simple stress relaxation tests. The newly proposed parameter, Ksrf, did an excellent job in correlating the dwell crack growth rates for the four heat treatments which were shown to have similar intrinsic environmental cyclic fatigue crack growth resistance.
Rubbo, Bruna; Fitzpatrick, Natalie K; Denaxas, Spiros; Daskalopoulou, Marina; Yu, Ning; Patel, Riyaz S; Hemingway, Harry
2015-01-01
Electronic health records (EHRs) offer the opportunity to ascertain clinical outcomes at large scale and low cost, thus facilitating cohort studies, quality of care research and clinical trials. For acute myocardial infarction (AMI) the extent to which different EHR sources are accessible and accurate remains uncertain. Using MEDLINE and EMBASE we identified thirty three studies, reporting a total of 128658 patients, published between January 2000 and July 2014 that permitted assessment of the validity of AMI diagnosis drawn from EHR sources against a reference such as manual chart review. In contrast to clinical practice, only one study used EHR-derived markers of myocardial necrosis to identify possible AMI cases, none used electrocardiogram findings and one used symptoms in the form of free text combined with coded diagnosis. The remaining studies relied mostly on coded diagnosis. Thirty one studies reported positive predictive value (PPV)≥ 70% between AMI diagnosis from both secondary care and primary care EHRs and the reference. Among fifteen studies reporting EHR-derived AMI phenotypes, three cross-referenced ST-segment elevation AMI diagnosis (PPV range 71-100%), two non-ST-segment elevation AMI (PPV 91.0, 92.1%), three non-fatal AMI (PPV range 82-92.2%) and six fatal AMI (PPV range 64-91.7%). Clinical coding of EHR-derived AMI diagnosis in primary care and secondary care was found to be accurate in different clinical settings and for different phenotypes. However, markers of myocardial necrosis, ECG and symptoms, the cornerstones of a clinical diagnosis, are underutilised and remain a challenge to retrieve from EHRs. Copyright © 2015. Published by Elsevier Ireland Ltd.
Kurogi, Ryota; Kada, Akiko; Nishimura, Kunihiro; Kamitani, Satoru; Nishimura, Ataru; Sayama, Tetsuro; Nakagawara, Jyoji; Toyoda, Kazunori; Ogasawara, Kuniaki; Ono, Junichi; Shiokawa, Yoshiaki; Aruga, Toru; Miyachi, Shigeru; Nagata, Izumi; Matsuda, Shinya; Yoshimura, Shinichi; Okuchi, Kazuo; Suzuki, Akifumi; Nakamura, Fumiaki; Onozuka, Daisuke; Hagihara, Akihito; Iihara, Koji
2018-05-01
OBJECTIVE Although heterogeneity in patient outcomes following subarachnoid hemorrhage (SAH) has been observed across different centers, the relative merits of clipping and coiling for SAH remain unknown. The authors sought to compare the patient outcomes between these therapeutic modalities using a large nationwide discharge database encompassing hospitals with different comprehensive stroke center (CSC) capabilities. METHODS They analyzed data from 5214 patients with SAH (clipping 3624, coiling 1590) who had been urgently hospitalized at 393 institutions in Japan in the period from April 2012 to March 2013. In-hospital mortality, modified Rankin Scale (mRS) score, cerebral infarction, complications, hospital length of stay, and medical costs were compared between the clipping and coiling groups after adjustment for patient-level and hospital-level characteristics by using mixed-model analysis. RESULTS Patients who had undergone coiling had significantly higher in-hospital mortality (12.4% vs 8.7%, OR 1.3) and a shorter median hospital stay (32.0 vs 37.0 days, p < 0.001) than those who had undergone clipping. The respective proportions of patients discharged with mRS scores of 3-6 (46.4% and 42.9%) and median medical costs (thousands US$, 35.7 and 36.7) were not significantly different between the groups. These results remained robust after further adjustment for CSC capabilities as a hospital-related covariate. CONCLUSIONS Despite the increasing use of coiling, clipping remains the mainstay treatment for SAH. Regardless of CSC capabilities, clipping was associated with reduced in-hospital mortality, similar unfavorable functional outcomes and medical costs, and a longer hospital stay as compared with coiling in 2012 in Japan. Further study is required to determine the influence of unmeasured confounders.
Robustness of inflation to inhomogeneous initial conditions
NASA Astrophysics Data System (ADS)
Clough, Katy; Lim, Eugene A.; DiNunno, Brandon S.; Fischler, Willy; Flauger, Raphael; Paban, Sonia
2017-09-01
We consider the effects of inhomogeneous initial conditions in both the scalar field profile and the extrinsic curvature on different inflationary models. In particular, we compare the robustness of small field inflation to that of large field inflation, using numerical simulations with Einstein gravity in 3+1 dimensions. We find that small field inflation can fail in the presence of subdominant gradient energies, suggesting that it is much less robust to inhomogeneities than large field inflation, which withstands dominant gradient energies. However, we also show that small field inflation can be successful even if some regions of spacetime start out in the region of the potential that does not support inflation. In the large field case, we confirm previous results that inflation is robust if the inflaton occupies the inflationary part of the potential. Furthermore, we show that increasing initial scalar gradients will not form sufficiently massive inflation-ending black holes if the initial hypersurface is approximately flat. Finally, we consider the large field case with a varying extrinsic curvature K, such that some regions are initially collapsing. We find that this may again lead to local black holes, but overall the spacetime remains inflationary if the spacetime is open, which confirms previous theoretical studies.
He, W; Zhao, S; Liu, X; Dong, S; Lv, J; Liu, D; Wang, J; Meng, Z
2013-12-04
Large-scale next-generation sequencing (NGS)-based resequencing detects sequence variations, constructs evolutionary histories, and identifies phenotype-related genotypes. However, NGS-based resequencing studies generate extraordinarily large amounts of data, making computations difficult. Effective use and analysis of these data for NGS-based resequencing studies remains a difficult task for individual researchers. Here, we introduce ReSeqTools, a full-featured toolkit for NGS (Illumina sequencing)-based resequencing analysis, which processes raw data, interprets mapping results, and identifies and annotates sequence variations. ReSeqTools provides abundant scalable functions for routine resequencing analysis in different modules to facilitate customization of the analysis pipeline. ReSeqTools is designed to use compressed data files as input or output to save storage space and facilitates faster and more computationally efficient large-scale resequencing studies in a user-friendly manner. It offers abundant practical functions and generates useful statistics during the analysis pipeline, which significantly simplifies resequencing analysis. Its integrated algorithms and abundant sub-functions provide a solid foundation for special demands in resequencing projects. Users can combine these functions to construct their own pipelines for other purposes.
Horticultural Performance of Eight American Elderberry Genotypes at Three Missouri Locations
Thomas, A.L.; Byers, P.L.; Avery, J.D.; Kaps, M.; Gu, S.
2016-01-01
American elderberry (Sambucus nigra subsp. canadensis) is being increasingly cultivated in North America for its edible and medicinal fruit and flowers, yet remains largely undeveloped as a horticultural crop. Productive genotypes with desirable horticultural attributes, including disease and insect resistance, precocity, uniform fruit ripening, and large berry size are needed in order to advance the commercial production of elderberries. A four-year study of eight elderberry genotypes was established in 2008 at three diverse Missouri (USA) locations. Phenology, plant morphology, pest susceptibility, productivity, and fruit characteristics data were collected over three growing seasons, 2009–2011. Significant differences for most phenological, horticultural, and fruit juice characteristics were observed among the three sites, three years, and eight genotypes. The genotype ‘Ozark’ was the earliest to break bud, produced fruit with high levels of soluble solids, and out-yielded most other genotypes at the three sites over the three-year study. None of the new genotypes produced berries as large as or larger than the standard ‘York’ which is known for its large fruit. Some of the genotypes tested, especially ‘Ozark’ show promise as potential cultivars and as breeding stock for further development of elderberry as a commercially-viable horticultural crop. PMID:27158183
Horticultural Performance of Eight American Elderberry Genotypes at Three Missouri Locations.
Thomas, A L; Byers, P L; Avery, J D; Kaps, M; Gu, S
2015-01-12
American elderberry ( Sambucus nigra subsp. canadensis ) is being increasingly cultivated in North America for its edible and medicinal fruit and flowers, yet remains largely undeveloped as a horticultural crop. Productive genotypes with desirable horticultural attributes, including disease and insect resistance, precocity, uniform fruit ripening, and large berry size are needed in order to advance the commercial production of elderberries. A four-year study of eight elderberry genotypes was established in 2008 at three diverse Missouri (USA) locations. Phenology, plant morphology, pest susceptibility, productivity, and fruit characteristics data were collected over three growing seasons, 2009-2011. Significant differences for most phenological, horticultural, and fruit juice characteristics were observed among the three sites, three years, and eight genotypes. The genotype 'Ozark' was the earliest to break bud, produced fruit with high levels of soluble solids, and out-yielded most other genotypes at the three sites over the three-year study. None of the new genotypes produced berries as large as or larger than the standard 'York' which is known for its large fruit. Some of the genotypes tested, especially 'Ozark' show promise as potential cultivars and as breeding stock for further development of elderberry as a commercially-viable horticultural crop.
Computational Simulation of Large Droplet Icing
DOT National Transportation Integrated Search
1996-01-01
Certification for flight into known icing remains one of the more challenging goals for aircraft manufacturers. This activity has been further complicated by the current interest in large droplet icing. Due to the lack of data available on the meteor...
Quest: A Hybrid Faculty Teaching and Learning Community
ERIC Educational Resources Information Center
Joseph, Siny; Oh, Jung; Ackerman, Patricia
2018-01-01
Faculty members often collaborate on research and service projects, but teaching remains a relatively solitary activity (Gizir & Simsek, 2005 ; Ramsden, 1998 ). While students attend classes taught by various faculty members, faculty members remain largely unaware of the innovative and pedagogical improvements in teaching made by their…
Sutherland, Ben J.G.; Rico, Ciro; Audet, Céline; Bernatchez, Louis
2017-01-01
Whole-genome duplication (WGD) can have large impacts on genome evolution, and much remains unknown about these impacts. This includes the mechanisms of coping with a duplicated sex determination system and whether this has an impact on increasing the diversity of sex determination mechanisms. Other impacts include sexual conflict, where alleles having different optimums in each sex can result in sequestration of genes into nonrecombining sex chromosomes. Sex chromosome development itself may involve sex-specific recombination rate (i.e., heterochiasmy), which is also poorly understood. The family Salmonidae is a model system for these phenomena, having undergone autotetraploidization and subsequent rediploidization in most of the genome at the base of the lineage. The salmonid master sex determining gene is known, and many species have nonhomologous sex chromosomes, putatively due to transposition of this gene. In this study, we identify the sex chromosome of Brook Charr Salvelinus fontinalis and compare sex chromosome identities across the lineage (eight species and four genera). Although nonhomology is frequent, homologous sex chromosomes and other consistencies are present in distantly related species, indicating probable convergence on specific sex and neo-sex chromosomes. We also characterize strong heterochiasmy with 2.7-fold more crossovers in maternal than paternal haplotypes with paternal crossovers biased to chromosome ends. When considering only rediploidized chromosomes, the overall heterochiasmy trend remains, although with only 1.9-fold more recombination in the female than the male. Y chromosome crossovers are restricted to a single end of the chromosome, and this chromosome contains a large interspecific inversion, although its status between males and females remains unknown. Finally, we identify quantitative trait loci (QTL) for 21 unique growth, reproductive, and stress-related phenotypes to improve knowledge of the genetic architecture of these traits important to aquaculture and evolution. PMID:28626004
Wang, Li; Zhang, Fengying; Pilot, Eva; Yu, Jie; Holdaway, Jennifer; Yang, Linsheng; Li, Yonghua; Wang, Wuyi; Vardoulakis, Sotiris; Krafft, Thomas
2018-01-01
Due to rapid urbanization, industrialization and motorization, a large number of Chinese cities are affected by heavy air pollution. In order to explore progress, remaining challenges, and sustainability of air pollution control in the Beijing-Tianjin-Hebei (BTH) region after 2013, a mixed method analysis was undertaken. The quantitative analysis comprised an overview of air quality management in the BTH region. Semi-structured expert interviews were conducted with 12 stakeholders from various levels of government and research institutions who played substantial roles either in decision-making or in research and advising on air pollution control in the BTH region. The results indicated that with the stringent air pollution control policies, the air quality in BTH meets the targets of the Air Pollution Prevention and Control Action Plan. However, improvements vary across the region and for different pollutants. Although implementation has been decisive and was at least in parts effectively enforced, significant challenges remained with regard to industrial and traffic emission control, and national air quality limits continued to be significantly exceeded and competing development interests remained mainly unsolved. There were also concerns about the sustainability of the current air pollution control measures especially for industries due to the top-down enforcement, and the associated large burden of social cost including unemployment and social inequity resulting industrial restructuring. Better mechanisms for ensuring cross-sectoral coordination and for improved central-local government communication were suggested. Further suggestions were provided to improve the conceptual design and effective implementation of respective air pollution control strategies in BTH. Our study highlights some of the major hurdles that need to be addressed to succeed with a comprehensive air pollution control management for the Chinese mega-urban agglomerations. PMID:29425189
When and why do old adults outsource control to the environment?
Mayr, Ulrich; Spieler, Daniel H; Hutcheon, Thomas G
2015-09-01
Old adults' tendency to rely on information present in the environment rather than internal representations has been frequently noted, but is not well understood. The fade-out paradigm provides a useful model situation to study this internal-to-external shift across the life span: Subjects need to transition from an initial, cued task-switching phase to a fade-out phase where only 1 task remains relevant. Old adults exhibit large response-time "fade-out costs," mainly because they continue to consult the task cues. Here we show that age differences in fade-out costs remain very large even when we insert between the task-switching and the fade-out phase 20 single-task trials without task cues (during which even old adults' performance becomes highly fluent; Experiment 1), but costs in old adults are eliminated when presenting an on-screen instruction to focus on the 1 remaining task at the transition point between the task-switching and fade-out phase (Experiment 2). Furthermore, old adults, but not young adults, also exhibited "fade-in costs" when they were instructed to perform an initial single-task phase that would be followed by the cued task-switching phase (Experiment 3). Combined, these results show that old adults' tendency to overutilize external support is not a problem of perseverating earlier-relevant control settings. Instead, old adults seem less likely to initiate the necessary reconfiguration process when transitioning from 1 phase to the next because they use underspecified task models that lack the higher-level distinction between those contexts that do and that do not require external support. (c) 2015 APA, all rights reserved).
Braille in the Sighted: Teaching Tactile Reading to Sighted Adults.
Bola, Łukasz; Siuda-Krzywicka, Katarzyna; Paplińska, Małgorzata; Sumera, Ewa; Hańczur, Paweł; Szwed, Marcin
2016-01-01
Blind people are known to have superior perceptual abilities in their remaining senses. Several studies suggest that these enhancements are dependent on the specific experience of blind individuals, who use those remaining senses more than sighted subjects. In line with this view, sighted subjects, when trained, are able to significantly progress in relatively simple tactile tasks. However, the case of complex tactile tasks is less obvious, as some studies suggest that visual deprivation itself could confer large advantages in learning them. It remains unclear to what extent those complex skills, such as braille reading, can be learnt by sighted subjects. Here we enrolled twenty-nine sighted adults, mostly braille teachers and educators, in a 9-month braille reading course. At the beginning of the course, all subjects were naive in tactile braille reading. After the course, almost all were able to read whole braille words at a mean speed of 6 words-per-minute. Subjects with low tactile acuity did not differ significantly in braille reading speed from the rest of the group, indicating that low tactile acuity is not a limiting factor for learning braille, at least at this early stage of learning. Our study shows that most sighted adults can learn whole-word braille reading, given the right method and a considerable amount of motivation. The adult sensorimotor system can thus adapt, to some level, to very complex tactile tasks without visual deprivation. The pace of learning in our group was comparable to congenitally and early blind children learning braille in primary school, which suggests that the blind's mastery of complex tactile tasks can, to a large extent, be explained by experience-dependent mechanisms.
Braille in the Sighted: Teaching Tactile Reading to Sighted Adults
Bola, Łukasz; Siuda-Krzywicka, Katarzyna; Paplińska, Małgorzata; Sumera, Ewa; Hańczur, Paweł; Szwed, Marcin
2016-01-01
Blind people are known to have superior perceptual abilities in their remaining senses. Several studies suggest that these enhancements are dependent on the specific experience of blind individuals, who use those remaining senses more than sighted subjects. In line with this view, sighted subjects, when trained, are able to significantly progress in relatively simple tactile tasks. However, the case of complex tactile tasks is less obvious, as some studies suggest that visual deprivation itself could confer large advantages in learning them. It remains unclear to what extent those complex skills, such as braille reading, can be learnt by sighted subjects. Here we enrolled twenty-nine sighted adults, mostly braille teachers and educators, in a 9-month braille reading course. At the beginning of the course, all subjects were naive in tactile braille reading. After the course, almost all were able to read whole braille words at a mean speed of 6 words-per-minute. Subjects with low tactile acuity did not differ significantly in braille reading speed from the rest of the group, indicating that low tactile acuity is not a limiting factor for learning braille, at least at this early stage of learning. Our study shows that most sighted adults can learn whole-word braille reading, given the right method and a considerable amount of motivation. The adult sensorimotor system can thus adapt, to some level, to very complex tactile tasks without visual deprivation. The pace of learning in our group was comparable to congenitally and early blind children learning braille in primary school, which suggests that the blind’s mastery of complex tactile tasks can, to a large extent, be explained by experience-dependent mechanisms. PMID:27187496
McCoy, Scott W.; Coe, Jeffrey A.; Kean, Jason W.; Tucker, Greg E.; Staley, Dennis M.; Wasklewicz, Thad A.
2011-01-01
Debris flows initiated by surface-water runoff during short duration, moderate- to high-intensity rainfall are common in steep, rocky, and sparsely vegetated terrain. Yet large uncertainties remain about the potential for a flow to grow through entrainment of loose debris, which make formulation of accurate mechanical models of debris-flow routing difficult. Using a combination of in situ measurements of debris flow dynamics, video imagery, tracer rocks implanted with passive integrated transponders (PIT) and pre- and post-flow 2-cm resolution digital terrain models (terrain data presented in a companion paper by STALEY et alii, 2011), we investigated the entrainment and transport response of debris flows at Chalk Cliffs, CO, USA. Four monitored events during the summer of 2009 all initiated from surface-water runoff, generally less than an hour after the first measurable rain. Despite reach-scale morphology that remained relatively constant, the four flow events displayed a range of responses, from long-runout flows that entrained significant amounts of channel sediment and dammed the main-stem river, to smaller, short-runout flows that were primarily depositional in the upper basin. Tracer-rock travel-distance distributions for these events were bimodal; particles either remained immobile or they travelled the entire length of the catchment. The long-runout, large-entrainment flow differed from the other smaller flows by the following controlling factors: peak 10-minute rain intensity; duration of significant flow in the channel; and to a lesser extent, peak surge depth and velocity. Our growing database of natural debris-flow events can be used to develop linkages between observed debris-flow transport and entrainment responses and the controlling rainstorm characteristics and flow properties.
Wang, Li; Zhang, Fengying; Pilot, Eva; Yu, Jie; Nie, Chengjing; Holdaway, Jennifer; Yang, Linsheng; Li, Yonghua; Wang, Wuyi; Vardoulakis, Sotiris; Krafft, Thomas
2018-02-09
Due to rapid urbanization, industrialization and motorization, a large number of Chinese cities are affected by heavy air pollution. In order to explore progress, remaining challenges, and sustainability of air pollution control in the Beijing-Tianjin-Hebei (BTH) region after 2013, a mixed method analysis was undertaken. The quantitative analysis comprised an overview of air quality management in the BTH region. Semi-structured expert interviews were conducted with 12 stakeholders from various levels of government and research institutions who played substantial roles either in decision-making or in research and advising on air pollution control in the BTH region. The results indicated that with the stringent air pollution control policies, the air quality in BTH meets the targets of the Air Pollution Prevention and Control Action Plan. However, improvements vary across the region and for different pollutants. Although implementation has been decisive and was at least in parts effectively enforced, significant challenges remained with regard to industrial and traffic emission control, and national air quality limits continued to be significantly exceeded and competing development interests remained mainly unsolved. There were also concerns about the sustainability of the current air pollution control measures especially for industries due to the top-down enforcement, and the associated large burden of social cost including unemployment and social inequity resulting industrial restructuring. Better mechanisms for ensuring cross-sectoral coordination and for improved central-local government communication were suggested. Further suggestions were provided to improve the conceptual design and effective implementation of respective air pollution control strategies in BTH. Our study highlights some of the major hurdles that need to be addressed to succeed with a comprehensive air pollution control management for the Chinese mega-urban agglomerations.
Micali, Nadia; Horton, N J; Crosby, R D; Swanson, S A; Sonneville, K R; Solmi, F; Calzo, J P; Eddy, K T; Field, A E
2017-02-01
Diagnostic criteria for eating disorders (ED) remain largely based on clinical presentations, but do not capture the full range of behaviours in the population. We aimed to derive an empirically based ED behaviour classification using behavioural and body mass index (BMI) indicators at three time-points in adolescence, and to validate classes investigating prospective associations with adverse outcomes. Adolescents from the Avon Longitudinal Study of Parents and Children (ALSPAC) provided data on ED at age 14 (n = 6615), 16 (n = 5888), and 18 years (n = 5100), and had weight and height measured. Psychological and behavioural outcomes were assessed at 15.5/16 and 17.5/18 years. We fit gender- and age-stratified latent class models, and employed logistic regression to investigate associations between classes and later outcomes. One asymptomatic and two symptomatic (largely representing higher and lower frequency ED behaviours) classes were observed at each time-point, although their relative prevalence varied by age and gender. The majority of girls in symptomatic classes remained symptomatic at subsequent assessments. Girls in symptomatic classes had higher odds of subsequent anxiety and depressive disorders, binge drinking, drug use, and deliberate self-harm. Data analyses were underpowered amongst boys. The presence of two symptomatic classes (characterised by different ED behaviour frequency) and their prospective association with adverse outcomes suggest a need to refine diagnostic thresholds based on empirical data. Despite some instability of classes, particularly in mid-adolescence, evidence that half of girls in symptomatic classes remained symptomatic suggests persistence of ED behaviours in adolescence, and highlights a need for early identification to reduce chronicity.
Maternal and pregnancy-related death: causes and frequencies in an autopsy study population.
Buschmann, Claas; Schmidbauer, Martina; Tsokos, Michael
2013-09-01
Maternal deaths during pregnancy, both from pregnancy-related or other causes, are rare in Western industrialized countries. In this study we report maternal and pregnancy-related deaths in a large autopsy population focusing on medical history, autopsy findings and histological examinations. Medico-legal autopsy files (n = 11,270) from the Institute of Legal Medicine and Forensic Sciences, University Medical Centre Charité, University of Berlin, and the State Institute of Legal and Social Medicine, Berlin, from 2005 to 2010 were reviewed. All female cases between 15 and 49 years were checked for maternal and pregnancy-related death, and deaths of pregnant women from non-natural causes were also included. Fatalities that met the chosen criteria were classified as "direct gestational death," "indirect gestational death" or "non-gestational death." 13 female fatalities (0.12 %) met the chosen criteria (median age 28 years ± 6.87 SD). Eight (61.5 %) women died in-hospital, four (30.8 %) at home, and one woman died in public. Three cases (23.1 %) were "non-gestational deaths," and one case (7.7 %) remained unclear after autopsy and additional examinations. Of the remaining nine cases, six cases (46.5 %) were "direct gestational deaths," and two cases (15.4 %) were "indirect gestational deaths." One case (7.7 %) was not to be defined as "late maternal death," but the cause of death seemed to be directly related to previous gestation ["(very) late maternal death"]. Maternal deaths during pregnancy, both from pregnancy-related or other causes, remain an uncommon event in routine forensic autopsy practice. We report on the collection and analysis of maternal and pregnancy-related deaths in a large autopsy population, with particular attention to the phenomenology of pregnancy, pathophysiological changes in different organ systems and their detection, and the forensic autopsy assessment.
Abrams, Jasmine A; Javier, Sarah J; Maxwell, Morgan L; Belgrave, Faye Z; Nguyen, Boa Anh
2016-04-01
Research attempting to identify similarities or disentangle differences in ethnic minority gender role beliefs has been largely absent in the literature, and a gap remains for qualitative examinations of such phenomena. The purpose of this study is to fill this gap in the literature by providing a qualitative examination of the differences and similarities of gender role beliefs among African American and Vietnamese American women. Thematic analyses were conducted with data gathered from 8 focus groups with 44 African American women (mean age = 44 years) and 4 focus Groups 47 Vietnamese American women (mean age = 42 years). Women were diverse in generational, religious, and educational backgrounds. Two similar primary themes emerged: (a) women's roles as chief caretakers and (b) women's responsibility to fulfill multiple roles. There were also similar experiences of a need to convey strength and be self-sacrificial. Two distinct differences that emerged from the focus groups were beliefs about interpersonal interactions and perceptions of societal expectations. This study demonstrates that the conceptualization of gender role beliefs, although at times similar, diverges among culturally different groups. To account for these and other culturally nuanced differences, measures of gender role beliefs should be culturally tailored and culturally specific. However, researchers have largely excluded ethnic minority women in the development of the most widely used measures of gender role beliefs in the U.S. The inclusion of diverse women in research will help prevent pitfalls of conflating and ignoring intragroup differences among different groups of marginalized women. (c) 2016 APA, all rights reserved).
DOE Office of Scientific and Technical Information (OSTI.GOV)
Adamek, Julian; Daverio, David; Durrer, Ruth
We present a new N-body code, gevolution , for the evolution of large scale structure in the Universe. Our code is based on a weak field expansion of General Relativity and calculates all six metric degrees of freedom in Poisson gauge. N-body particles are evolved by solving the geodesic equation which we write in terms of a canonical momentum such that it remains valid also for relativistic particles. We validate the code by considering the Schwarzschild solution and, in the Newtonian limit, by comparing with the Newtonian N-body codes Gadget-2 and RAMSES . We then proceed with a simulation ofmore » large scale structure in a Universe with massive neutrinos where we study the gravitational slip induced by the neutrino shear stress. The code can be extended to include different kinds of dark energy or modified gravity models and going beyond the usually adopted quasi-static approximation. Our code is publicly available.« less
Ubiquitinated Proteome: Ready for Global?*
Shi, Yi; Xu, Ping; Qin, Jun
2011-01-01
Ubiquitin (Ub) is a small and highly conserved protein that can covalently modify protein substrates. Ubiquitination is one of the major post-translational modifications that regulate a broad spectrum of cellular functions. The advancement of mass spectrometers as well as the development of new affinity purification tools has greatly expedited proteome-wide analysis of several post-translational modifications (e.g. phosphorylation, glycosylation, and acetylation). In contrast, large-scale profiling of lysine ubiquitination remains a challenge. Most recently, new Ub affinity reagents such as Ub remnant antibody and tandem Ub binding domains have been developed, allowing for relatively large-scale detection of several hundreds of lysine ubiquitination events in human cells. Here we review different strategies for the identification of ubiquitination site and discuss several issues associated with data analysis. We suggest that careful interpretation and orthogonal confirmation of MS spectra is necessary to minimize false positive assignments by automatic searching algorithms. PMID:21339389
ηc Hadroproduction at Large Hadron Collider Challenges NRQCD Factorization
NASA Astrophysics Data System (ADS)
Butenschoen, Mathias; He, Zhi-Guo; Kniehl, Bernd A.
2017-03-01
We report on our analysis [1] of prompt ηc meson production, measured by the LHCb Collaboration at the Large Hadron Collider, within the framework of non-relativistic QCD (NRQCD) factorization up to the sub-leading order in both the QCD coupling constant αs and the relative velocity v of the bound heavy quarks. We thereby convert various sets of J/ψ and χc,J long-distance matrix elements (LDMEs), determined by different groups in J/ψ and χc,J yield and polarization fits, to ηc and hc production LDMEs making use of the NRQCD heavy quark spin symmetry. The resulting predictions for ηc hadroproduction in all cases greatly overshoot the LHCb data, while the color-singlet model contributions alone would indeed be sufficient. We investigate the consequences for the universality of the LDMEs, and show how the observed tensions remain in follow-up works by other groups.
Longitudinal Stability in Reading Comprehension Is Largely Heritable from Grades 1 to 6
Soden, Brooke; Christopher, Micaela E.; Hulslander, Jacqueline; Olson, Richard K.; Cutting, Laurie; Keenan, Janice M.; Thompson, Lee A.; Wadsworth, Sally J.; Willcutt, Erik G.; Petrill, Stephen A.
2015-01-01
Reading comprehension is a foundational academic skill and significant attention has focused on reading development. This report is the first to examine the stability and change in genetic and environmental influences on reading comprehension across Grades 1 to 6. This developmental range is particularly important because it encompasses the timespan in which most children move from learning how to read to using reading for learning. Longitudinal simplex models were fitted separately for two independent twin samples (N = 706; N = 976). Results suggested that the shared environment contributed to variance in early but not later reading. Instead, stability in reading development was largely mediated by continuous genetic influences. Thus, although reading is clearly a learned skill and the environment remains important for reading development, individual differences in reading comprehension appear to be also influenced by a core of genetic stability that persists through the developmental course of reading. PMID:25602760
Rates of speciation in the fossil record
NASA Technical Reports Server (NTRS)
Sepkoski, J. J. Jr; Sepkoski JJ, J. r. (Principal Investigator)
1998-01-01
Data from palaeontology and biodiversity suggest that the global biota should produce an average of three new species per year. However, the fossil record shows large variation around this mean. Rates of origination have declined through the Phanerozoic. This appears to have been largely a function of sorting among higher taxa (especially classes), which exhibit characteristic rates of speciation (and extinction) that differ among them by nearly an order of magnitude. Secular decline of origination rates is hardly constant, however; many positive deviations reflect accelerated speciation during rebounds from mass extinctions. There has also been general decline in rates of speciation within major taxa through their histories, although rates have tended to remain higher among members in tropical regions. Finally, pulses of speciation appear sometimes to be associated with climate change, although moderate oscillations of climate do not necessarily promote speciation despite forcing changes in species' geographical ranges.
ADJUST: An automatic EEG artifact detector based on the joint use of spatial and temporal features.
Mognon, Andrea; Jovicich, Jorge; Bruzzone, Lorenzo; Buiatti, Marco
2011-02-01
A successful method for removing artifacts from electroencephalogram (EEG) recordings is Independent Component Analysis (ICA), but its implementation remains largely user-dependent. Here, we propose a completely automatic algorithm (ADJUST) that identifies artifacted independent components by combining stereotyped artifact-specific spatial and temporal features. Features were optimized to capture blinks, eye movements, and generic discontinuities on a feature selection dataset. Validation on a totally different EEG dataset shows that (1) ADJUST's classification of independent components largely matches a manual one by experts (agreement on 95.2% of the data variance), and (2) Removal of the artifacted components detected by ADJUST leads to neat reconstruction of visual and auditory event-related potentials from heavily artifacted data. These results demonstrate that ADJUST provides a fast, efficient, and automatic way to use ICA for artifact removal. Copyright © 2010 Society for Psychophysiological Research.
The optimal density of cellular solids in axial tension.
Mihai, L Angela; Alayyash, Khulud; Wyatt, Hayley
2017-05-01
For cellular bodies with uniform cell size, wall thickness, and shape, an important question is whether the same volume of material has the same effect when arranged as many small cells or as fewer large cells. To answer this question, for finite element models of periodic structures of Mooney-type material with different structural geometry and subject to large strain deformations, we identify a nonlinear elastic modulus as the ratio between the mean effective stress and the mean effective strain in the solid cell walls, and show that this modulus increases when the thickness of the walls increases, as well as when the number of cells increases while the volume of solid material remains fixed. Since, under the specified conditions, this nonlinear elastic modulus increases also as the corresponding mean stress increases, either the mean modulus or the mean stress can be employed as indicator when the optimum wall thickness or number of cells is sought.
Urban parasitology: visceral leishmaniasis in Brazil.
Harhay, Michael O; Olliaro, Piero L; Costa, Dorcas Lamounier; Costa, Carlos Henrique Nery
2011-09-01
Since the early 1980s, visceral leishmaniasis (VL) which is, in general, a rural zoonotic disease, has spread to the urban centers of the north, and now the south and west of Brazil. The principal drivers differ between cities, though human migration, large urban canid populations (animal reservoir), and a decidedly peripatetic and adaptable sand fly vector are the primary forces. The exact number of urban cases remains unclear as a result of challenges with surveillance. However, the number of urban cases registered continues to increase annually. Most control initiatives (e.g. culling infected dogs and household spraying to kill the sand fly) could be effective, but have proven hard to maintain at large scales due to logistical, financial and other reasons. In this article, the urbanization of VL in Brazil is reviewed, touching on these and other topics related to controlling VL within and outside Brazil. Copyright © 2011 Elsevier Ltd. All rights reserved.
Idiosyncratic responding during movie-watching predicted by age differences in attentional control
Campbell, Karen L.; Shafto, Meredith A.; Wright, Paul; Tsvetanov, Kamen A.; Geerligs, Linda; Cusack, Rhodri; Tyler, Lorraine K.; Brayne, Carol; Bullmore, Ed; Calder, Andrew; Cusack, Rhodri; Dalgleish, Tim; Duncan, John; Henson, Rik; Matthews, Fiona; Marslen-Wilson, William; Rowe, James; Shafto, Meredith; Campbell, Karen; Cheung, Teresa; Davis, Simon; Geerligs, Linda; Kievit, Rogier; McCarrey, Anna; Price, Darren; Taylor, Jason; Tsvetanov, Kamen; Williams, Nitin; Bates, Lauren; Emery, Tina; Erzinçlioglu, Sharon; Gadie, Andrew; Gerbase, Sofia; Georgieva, Stanimira; Hanley, Claire; Parkin, Beth; Troy, David; Allen, Jodie; Amery, Gillian; Amunts, Liana; Barcroft, Anne; Castle, Amanda; Dias, Cheryl; Dowrick, Jonathan; Fair, Melissa; Fisher, Hayley; Goulding, Anna; Grewal, Adarsh; Hale, Geoff; Hilton, Andrew; Johnson, Frances; Johnston, Patricia; Kavanagh-Williamson, Thea; Kwasniewska, Magdalena; McMinn, Alison; Norman, Kim; Penrose, Jessica; Roby, Fiona; Rowland, Diane; Sargeant, John; Squire, Maggie; Stevens, Beth; Stoddart, Aldabra; Stone, Cheryl; Thompson, Tracy; Yazlik, Ozlem; Dixon, Marie; Barnes, Dan; Hillman, Jaya; Mitchell, Joanne; Villis, Laura; Tyler, Lorraine K.
2015-01-01
Much is known about how age affects the brain during tightly controlled, though largely contrived, experiments, but do these effects extrapolate to everyday life? Naturalistic stimuli, such as movies, closely mimic the real world and provide a window onto the brain's ability to respond in a timely and measured fashion to complex, everyday events. Young adults respond to these stimuli in a highly synchronized fashion, but it remains to be seen how age affects neural responsiveness during naturalistic viewing. To this end, we scanned a large (N = 218), population-based sample from the Cambridge Centre for Ageing and Neuroscience (Cam-CAN) during movie-watching. Intersubject synchronization declined with age, such that older adults' response to the movie was more idiosyncratic. This decreased synchrony related to cognitive measures sensitive to attentional control. Our findings suggest that neural responsivity changes with age, which likely has important implications for real-world event comprehension and memory. PMID:26359527
NASA Astrophysics Data System (ADS)
Fu, Li; Merabia, Samy; Joly, Laurent
2017-11-01
Thermo-osmotic and related thermophoretic phenomena can be found in many situations from biology to colloid science, but the underlying molecular mechanisms remain largely unexplored. Using molecular dynamics simulations, we measure the thermo-osmosis coefficient by both mechanocaloric and thermo-osmotic routes, for different solid-liquid interfacial energies. The simulations reveal, in particular, the crucial role of nanoscale interfacial hydrodynamics. For nonwetting surfaces, thermo-osmotic transport is largely amplified by hydrodynamic slip at the interface. For wetting surfaces, the position of the hydrodynamic shear plane plays a key role in determining the amplitude and sign of the thermo-osmosis coefficient. Finally, we measure a giant thermo-osmotic response of the water-graphene interface, which we relate to the very low interfacial friction displayed by this system. These results open new perspectives for the design of efficient functional interfaces for, e.g., waste-heat harvesting.
[Application of Kohonen Self-Organizing Feature Maps in QSAR of human ADMET and kinase data sets].
Hegymegi-Barakonyi, Bálint; Orfi, László; Kéri, György; Kövesdi, István
2013-01-01
QSAR predictions have been proven very useful in a large number of studies for drug design, such as kinase inhibitor design as targets for cancer therapy, however the overall predictability often remains unsatisfactory. To improve predictability of ADMET features and kinase inhibitory data, we present a new method using Kohonen's Self-Organizing Feature Map (SOFM) to cluster molecules based on explanatory variables (X) and separate dissimilar ones. We calculated SOFM clusters for a large number of molecules with human ADMET and kinase inhibitory data, and we showed that chemically similar molecules were in the same SOFM cluster, and within such clusters the QSAR models had significantly better predictability. We used also target variables (Y, e.g. ADMET) jointly with X variables to create a novel type of clustering. With our method, cells of loosely coupled XY data could be identified and separated into different model building sets.
Milella, Marco; Giovanna Belcastro, Maria; Zollikofer, Christoph P E; Mariotti, Valentina
2012-07-01
Entheseal changes are traditionally included in a large array of skeletal features commonly referred to as "skeletal markers of activity." However, medical studies and recent anthropological analyses of identified skeletal series suggest a complex combination of physiological and biomechanical factors underlying the variability of such "markers." The aim of this study is to examine the relationship between age, sex, physical activity, and entheseal variability. To this end, 23 postcranial entheses are examined in a large (N = 484) Italian contemporary skeletal series using standardized scoring methods. The sample comprises subjects of known age, sex and, mostly, occupation. Results show a strong relationship between age and entheseal changes. Differences between sexes are also highlighted, while the effects of physical activity appear moderate. Altogether, our study indicates that entheseal morphology primarily reflects the age of an individual, while correlation with lifetime activity remains ambiguous. Copyright © 2012 Wiley Periodicals, Inc.
Fu, Li; Merabia, Samy; Joly, Laurent
2017-11-24
Thermo-osmotic and related thermophoretic phenomena can be found in many situations from biology to colloid science, but the underlying molecular mechanisms remain largely unexplored. Using molecular dynamics simulations, we measure the thermo-osmosis coefficient by both mechanocaloric and thermo-osmotic routes, for different solid-liquid interfacial energies. The simulations reveal, in particular, the crucial role of nanoscale interfacial hydrodynamics. For nonwetting surfaces, thermo-osmotic transport is largely amplified by hydrodynamic slip at the interface. For wetting surfaces, the position of the hydrodynamic shear plane plays a key role in determining the amplitude and sign of the thermo-osmosis coefficient. Finally, we measure a giant thermo-osmotic response of the water-graphene interface, which we relate to the very low interfacial friction displayed by this system. These results open new perspectives for the design of efficient functional interfaces for, e.g., waste-heat harvesting.
Quantifying the uncertainty in heritability
Furlotte, Nicholas A; Heckerman, David; Lippert, Christoph
2014-01-01
The use of mixed models to determine narrow-sense heritability and related quantities such as SNP heritability has received much recent attention. Less attention has been paid to the inherent variability in these estimates. One approach for quantifying variability in estimates of heritability is a frequentist approach, in which heritability is estimated using maximum likelihood and its variance is quantified through an asymptotic normal approximation. An alternative approach is to quantify the uncertainty in heritability through its Bayesian posterior distribution. In this paper, we develop the latter approach, make it computationally efficient and compare it to the frequentist approach. We show theoretically that, for a sufficiently large sample size and intermediate values of heritability, the two approaches provide similar results. Using the Atherosclerosis Risk in Communities cohort, we show empirically that the two approaches can give different results and that the variance/uncertainty can remain large. PMID:24670270
Naderi, Saeid; Rezaei, Hamid-Reza; Taberlet, Pierre; Zundel, Stéphanie; Rafat, Seyed-Abbas; Naghash, Hamid-Reza; El-Barody, Mohamed A. A.; Ertugrul, Okan; Pompanon, François
2007-01-01
Background From the beginning of domestication, the transportation of domestic animals resulted in genetic and demographic processes that explain their present distribution and genetic structure. Thus studying the present genetic diversity helps to better understand the history of domestic species. Methodology/Principal Findings The genetic diversity of domestic goats has been characterized with 2430 individuals from all over the old world, including 946 new individuals from regions poorly studied until now (mainly the Fertile Crescent). These individuals represented 1540 haplotypes for the HVI segment of the mitochondrial DNA (mtDNA) control region. This large-scale study allowed the establishment of a clear nomenclature of the goat maternal haplogroups. Only five of the six previously defined groups of haplotypes were divergent enough to be considered as different haplogroups. Moreover a new mitochondrial group has been localized around the Fertile Crescent. All groups showed very high haplotype diversity. Most of this diversity was distributed among groups and within geographic regions. The weak geographic structure may result from the worldwide distribution of the dominant A haplogroup (more than 90% of the individuals). The large-scale distribution of other haplogroups (except one), may be related to human migration. The recent fragmentation of local goat populations into discrete breeds is not detectable with mitochondrial markers. The estimation of demographic parameters from mismatch analyses showed that all groups had a recent demographic expansion corresponding roughly to the period when domestication took place. But even with a large data set it remains difficult to give relative dates of expansion for different haplogroups because of large confidence intervals. Conclusions/Significance We propose standard criteria for the definition of the different haplogroups based on the result of mismatch analysis and on the use of sequences of reference. Such a method could be also applied for clarifying the nomenclature of mitochondrial haplogroups in other domestic species. PMID:17925860
Predicting vehicle fuel consumption patterns using floating vehicle data.
Du, Yiman; Wu, Jianping; Yang, Senyan; Zhou, Liutong
2017-09-01
The status of energy consumption and air pollution in China is serious. It is important to analyze and predict the different fuel consumption of various types of vehicles under different influence factors. In order to fully describe the relationship between fuel consumption and the impact factors, massive amounts of floating vehicle data were used. The fuel consumption pattern and congestion pattern based on large samples of historical floating vehicle data were explored, drivers' information and vehicles' parameters from different group classification were probed, and the average velocity and average fuel consumption in the temporal dimension and spatial dimension were analyzed respectively. The fuel consumption forecasting model was established by using a Back Propagation Neural Network. Part of the sample set was used to train the forecasting model and the remaining part of the sample set was used as input to the forecasting model. Copyright © 2017. Published by Elsevier B.V.
Growth and splitting of neural sequences in songbird vocal development
Okubo, Tatsuo S.; Mackevicius, Emily L.; Payne, Hannah L.; Lynch, Galen F.; Fee, Michale S.
2015-01-01
Neural sequences are a fundamental feature of brain dynamics underlying diverse behaviors, but the mechanisms by which they develop during learning remain unknown. Songbirds learn vocalizations composed of syllables; in adult birds, each syllable is produced by a different sequence of action potential bursts in the premotor cortical area HVC. Here we carried out recordings of large populations of HVC neurons in singing juvenile birds throughout learning to examine the emergence of neural sequences. Early in vocal development, HVC neurons begin producing rhythmic bursts, temporally locked to a ‘prototype’ syllable. Different neurons are active at different latencies relative to syllable onset to form a continuous sequence. Through development, as new syllables emerge from the prototype syllable, initially highly overlapping burst sequences become increasingly distinct. We propose a mechanistic model in which multiple neural sequences can emerge from the growth and splitting of a common precursor sequence. PMID:26618871
Abi Rached, L; McDermott, M F; Pontarotti, P
1999-02-01
The human Major Histocompatibility Complex (MHC) shares similarities with three other chromosome regions in human. This could be the vestige of ancestral large scale duplications. We discuss here the possibility i) that these duplications occurred during two rounds of tetraploidization supposed to have taken place during chordate evolution before the jawed vertebrate radiation, and ii) that one of the quadruplicate regions, relaxed of functional constraints, gave rise to the vertebrate MHC by a quick round of gene cis-duplication and cis-exon shuffling. These different rounds of cis-duplications and exon shufflings allowed the emergence of new genes participating in novel biological functions i.e. adaptive immune responses. Cis-duplications and cis-exon shufflings are ongoing processes in the evolution of some of these genes in this region as they have occurred and were fixed at different times and in different lineages during vertebrate evolution. In contrast, other genes within the MHC have remained stable since the emergence of jawed vertebrates.
Chan, Lai Gwen; Carvalhal, Adriana
2015-01-01
To describe a model of HIV psychiatry used in an urban hospital in Toronto and examine it against current literature. Using a narrative method, we elaborate on how this model delivers care across many different settings and the integral roles that the HIV psychiatrist plays in each of these settings. This is articulated against a backdrop of existing literature regarding models of HIV care. This model is an example of an integrated model as opposed to a traditional consultation-liaison model and is able to deliver seamless care while remaining focused on patient-centric care. An HIV psychiatrist delivers seamless and patient-centric care by journeying with patients across the healthcare spectrum and playing different roles in different care settings. Copyright © 2015 Elsevier Inc. All rights reserved.
Medical and Scientific Illustration in the United States (US).
Peres, Michael
2015-06-01
The field of Medical and Scientific Illustration in the United States is large and constantly changing. In 1974, when the author began his studies, everything about the field was different. At the time, a student in the U.S. could go to a number of Universities (4 year) or Colleges (2 year) to study this subject. More than forty years later, only a few programs still offer similar programs of study. The Rochester Institute of Technology (RIT), where the author is a professor and Randolph Community College in North Carolina are all that remain from the more than ten that had operated. These two programs are very different from one another and there is not adequate space in this article to expand on these differences. Program details can be found online at: http://cias.rit.edu/schools/photographic-arts-sciences/undergraduate-biomedical-photographic-communications.
What is the importance of classifying Aspergillus disease in cystic fibrosis patients?
Jones, Andrew M; Horsley, Alex; Denning, David W
2014-08-01
Aspergillus species are commonly isolated from lower respiratory tract samples of patients with cystic fibrosis (CF) and markers of immunological sensation to Aspergillus are frequently encountered in this group of patients; however, the contribution of Aspergillus to CF lung disease outside of the typical complications of ABPA and aspergilloma formation remains largely unclear. Patients with CF show discretely different responses to Aspergillus, though the underlying reasons for this variation are unknown. Recent work has begun to allow us to categorize patient responses to Aspergillus based upon molecular markers of infection and immune sensitization. Aspergillus sensitization and/or airway infection is associated with worse FEV1, in CF and other patients (asthma, chronic obstructive pulmonary disease, bronchiectasis). Classification of different clinical phenotypes of Aspergillus will enable future studies to determine the natural history of different manifestations of Aspergillus disease and evaluate the effects of intervention with antifungal therapy.
Tsunami and shelf resonance on the northern Chile coast
NASA Astrophysics Data System (ADS)
Cortés, Pablo; Catalán, Patricio A.; Aránguiz, Rafael; Bellotti, Giorgio
2017-09-01
This work presents the analysis of long waves resonance in two of the main cities along the northern coast of Chile, Arica, and Iquique, where a large tsunamigenic potential remains despite recent earthquakes. By combining a modal analysis solving the equation of free surface oscillations, with the analysis of background spectra derived from in situ measurements, the spatial and temporal structures of the modes are recovered. Comparison with spectra from three tsunamis of different characteristics shows that the modes found have been excited by past events. Moreover, the two locations show different response patterns. Arica is more sensitive to the characteristics of the tsunami source, whereas Iquique shows a smaller dependency and similar response for different tsunami events. Results are further compared with other methodologies with good agreement. These findings are relevant in characterizing the tsunami hazard in the area, and the methodology can be further extended to other regions along the Chilean coast.
Elucidation of high sensitivity of δ-HMX: New insight from first principles simulations
NASA Astrophysics Data System (ADS)
Kuklja, Maija M.; Tsyshevsky, Roman V.; Sharia, Onise
2017-01-01
Understanding of a significant difference in sensitivities of β and δ phases of cyclotetramethylene-tetranitramine (HMX) has been long one of the challenges in the field of high energy density materials. Despite many experimental and theoretical efforts to explain the high sensitivity of the δ phase, convincing reasons behind the HMX behavior remained unclear. We established that the presence of a polar surface in δ-HMX has fundamental implications for stability and overall chemical behavior of the material. A comparative quantum-chemical analysis of decomposition mechanisms in polar δ-HMX and nonpolar β-HMX discovered a considerable difference in dominating dissociation reactions, activation barriers, and reaction rates. The polarization-induced charge transfer offered a logical explanation for different sensitivity of β-HMX and δ-HMX polymorphs to detonation initiation. Our conclusions also removed long-standing contradictions and explained a large range of experimental data on thermal decomposition of HMX.
NASA Astrophysics Data System (ADS)
Ise, T.; Litton, C. M.; Giardina, C. P.; Ito, A.
2009-12-01
Plant partitioning of carbon (C) to above- vs. belowground, to growth vs. respiration, and to short vs. long lived tissues exerts a large influence on ecosystem structure and function with implications for the global C budget. Importantly, outcomes of process-based terrestrial vegetation models are likely to vary substantially with different C partitioning algorithms. However, controls on C partitioning patterns remain poorly quantified, and studies have yielded variable, and at times contradictory, results. A recent meta-analysis of forest studies suggests that the ratio of net primary production (NPP) and gross primary production (GPP) is fairly conservative across large scales. To illustrate the effect of this unique meta-analysis-based partitioning scheme (MPS), we compared an application of MPS to a terrestrial satellite-based (MODIS) GPP to estimate NPP vs. two global process-based vegetation models (Biome-BGC and VISIT) to examine the influence of C partitioning on C budgets of woody plants. Due to the temperature dependence of maintenance respiration, NPP/GPP predicted by the process-based models increased with latitude while the ratio remained constant with MPS. Overall, global NPP estimated with MPS was 17 and 27% lower than the process-based models for temperate and boreal biomes, respectively, with smaller differences in the tropics. Global equilibrium biomass of woody plants was then calculated from the NPP estimates and tissue turnover rates from VISIT. Since turnover rates differed greatly across tissue types (i.e., metabolically active vs. structural), global equilibrium biomass estimates were sensitive to the partitioning scheme employed. The MPS estimate of global woody biomass was 7-21% lower than that of the process-based models. In summary, we found that model output for NPP and equilibrium biomass was quite sensitive to the choice of C partitioning schemes. Carbon use efficiency (CUE; NPP/GPP) by forest biome and the globe. Values are means for 2001-2006.
Yoon, Frank B; Huskamp, Haiden A; Busch, Alisa B; Normand, Sharon-Lise T
2011-06-21
Studies of large policy interventions typically do not involve randomization. Adjustments, such as matching, can remove the bias due to observed covariates, but residual confounding remains a concern. In this paper we introduce two analytical strategies to bolster inferences of the effectiveness of policy interventions based on observational data. First, we identify how study groups may differ and then select a second comparison group on this source of difference. Second, we match subjects using a strategy that finely balances the distributions of key categorical covariates and stochastically balances on other covariates. An observational study of the effect of parity on the severely ill subjects enrolled in the Federal Employees Health Benefits (FEHB) Program illustrates our methods.
Plague: A Disease Which Changed the Path of Human Civilization.
Bramanti, Barbara; Stenseth, Nils Chr; Walløe, Lars; Lei, Xu
2016-01-01
Plague caused by Yersinia pestis is a zoonotic infection, i.e., it is maintained in wildlife by animal reservoirs and on occasion spills over into human populations, causing outbreaks of different entities. Large epidemics of plague, which have had significant demographic, social, and economic consequences, have been recorded in Western European historical documents since the sixth century. Plague has remained in Europe for over 1400 years, intermittently disappearing, yet it is not clear if there were reservoirs for Y. pestis in Western Europe or if the pathogen was rather reimported on different occasions from Asian reservoirs by human agency. The latter hypothesis thus far seems to be the most plausible one, as it is sustained by both ecological and climatological evidence, helping to interpret the phylogeny of this bacterium.
The importance of being dead: cell death mechanisms assessment in anti-sarcoma therapy.
Rello-Varona, Santiago; Herrero-Martín, David; Lagares-Tena, Laura; López-Alemany, Roser; Mulet-Margalef, Núria; Huertas-Martínez, Juan; Garcia-Monclús, Silvia; García Del Muro, Xavier; Muñoz-Pinedo, Cristina; Tirado, Oscar Martínez
2015-01-01
Cell death can occur through different mechanisms, defined by their nature and physiological implications. Correct assessment of cell death is crucial for cancer therapy success. Sarcomas are a large and diverse group of neoplasias from mesenchymal origin. Among cell death types, apoptosis is by far the most studied in sarcomas. Albeit very promising in other fields, regulated necrosis and other cell death circumstances (as so-called "autophagic cell death" or "mitotic catastrophe") have not been yet properly addressed in sarcomas. Cell death is usually quantified in sarcomas by unspecific assays and in most cases the precise sequence of events remains poorly characterized. In this review, our main objective is to put into context the most recent sarcoma cell death findings in the more general landscape of different cell death modalities.
Breather soliton dynamics in microresonators
NASA Astrophysics Data System (ADS)
Yu, Mengjie; Jang, Jae K.; Okawachi, Yoshitomo; Griffith, Austin G.; Luke, Kevin; Miller, Steven A.; Ji, Xingchen; Lipson, Michal; Gaeta, Alexander L.
2017-02-01
The generation of temporal cavity solitons in microresonators results in coherent low-noise optical frequency combs that are critical for applications in spectroscopy, astronomy, navigation or telecommunications. Breather solitons also form an important part of many different classes of nonlinear wave systems, manifesting themselves as a localized temporal structure that exhibits oscillatory behaviour. To date, the dynamics of breather solitons in microresonators remains largely unexplored, and its experimental characterization is challenging. Here we demonstrate the excitation of breather solitons in two different microresonator platforms based on silicon nitride and on silicon. We investigate the dependence of the breathing frequency on pump detuning and observe the transition from period-1 to period-2 oscillation. Our study constitutes a significant contribution to understanding the soliton dynamics within the larger context of nonlinear science.
Recent progress in multi-electrode spike sorting methods.
Lefebvre, Baptiste; Yger, Pierre; Marre, Olivier
2016-11-01
In recent years, arrays of extracellular electrodes have been developed and manufactured to record simultaneously from hundreds of electrodes packed with a high density. These recordings should allow neuroscientists to reconstruct the individual activity of the neurons spiking in the vicinity of these electrodes, with the help of signal processing algorithms. Algorithms need to solve a source separation problem, also known as spike sorting. However, these new devices challenge the classical way to do spike sorting. Here we review different methods that have been developed to sort spikes from these large-scale recordings. We describe the common properties of these algorithms, as well as their main differences. Finally, we outline the issues that remain to be solved by future spike sorting algorithms. Copyright © 2017 Elsevier Ltd. All rights reserved.
Linking behavioural syndromes and cognition: a behavioural ecology perspective
Sih, Andrew; Del Giudice, Marco
2012-01-01
With the exception of a few model species, individual differences in cognition remain relatively unstudied in non-human animals. One intriguing possibility is that variation in cognition is functionally related to variation in personality. Here, we review some examples and present hypotheses on relationships between personality (or behavioural syndromes) and individual differences in cognitive style. Our hypotheses are based largely on a connection between fast–slow behavioural types (BTs; e.g. boldness, aggressiveness, exploration tendency) and cognitive speed–accuracy trade-offs. We also discuss connections between BTs, cognition and ecologically important aspects of decision-making, including sampling, impulsivity, risk sensitivity and choosiness. Finally, we introduce the notion of cognition syndromes, and apply ideas from theories on adaptive behavioural syndromes to generate predictions on cognition syndromes. PMID:22927575
Unveiling the morphology of the acetabulum in octopus suckers and its role in attachment
Tramacere, Francesca; Pugno, Nicola M.; Kuba, Michael J.; Mazzolai, Barbara
2015-01-01
In recent years, the attachment mechanism of the octopus sucker has attracted the interest of scientists from different research areas, including biology, engineering, medicine and robotics. From a technological perspective, the main goal is to identify the underlying mechanisms involved in sucker attachment for use in the development of new generations of artificial devices and materials. Recently, the understanding of the morphology of the sucker has been significantly improved; however, the mechanisms that allow attachment remain largely unknown. In this work, we present new anatomical findings: specifically, a protuberance in the acetabular roof in five different octopus species; previously, this protuberance was identified by the authors in Octopus vulgaris. Moreover, we discuss the role of the protuberance and other anatomical structures in attachment with minimal energy consumption. PMID:25657834
Coastal Benthic Boundary Layer (CBBL) Research Program
1998-09-01
of gas volume and bubble size distribution on the basis of field seismo-acoustic signature remains . Indirect seismic evidence (large scale) of gas...regime was dominated by reversing tidal currents with typical speeds of 10-cm s -1 or less. Maximum bed shear stresses remained too low to resuspend or...Waals attractive force are assumed to remain unchanged for separations less than the cut-off distance, and (2) the mechanical interparticle normal force
Gorecki, Sébastien; Nesslany, Fabrice; Hubé, Daniel; Mullot, Jean-Ulrich; Vasseur, Paule; Marchioni, Eric; Camel, Valérie; Noël, Laurent; Le Bizec, Bruno; Guérin, Thierry; Feidt, Cyril; Archer, Xavier; Mahe, Aurélie; Rivière, Gilles
2017-12-01
Shells fired during World War I exhibited different explosive compounds and some of these weapons also contained a wide variety of chemical warfare agents. At the end of the war, for safety purposes, the large quantity of weapons remaining on the former front needed to be dismantled and destroyed. A large amount of the remaining shells was destroyed in specific sites which led to the contamination of the surroundings in Belgium and France. In the 1920s, 1.5 million chemical shells and 30,000 explosive shells were destroyed in a place close to the city of Verdun, in the East of France. In this paper, the risk for human health related to the consumption of foodstuffs produced on this site was assessed. To this end, food products of plant and animal origin were sampled in 2015-2016 and contaminant analyses were conducted. Human exposure was assessed using a specifically built methodology. The contaminants considered in this study were trace elements (TEs - primarily Zn, As, Pb and Cd), nitroaromatic explosives (trinitrotoluene, 2,4-dinitrotoluene, 2,6-dinitrotoluene, 2-amino-4,6-dinitroluene and 4-amino-2,6-dinitrotoluene), phenylarsenic compounds including diphenylarsinic acid and triphenylarsine, perchlorate, tetrabromoethane and vinyl bromide. Depending on the compound, different approaches were used to assess the risk for both adults and children. Exposure to these contaminants through the consumption of foodstuffs produced locally on the considered site was unlikely to be a health concern. However, as for inorganic arsenic, given the presence of highly contaminated zones, it was suggested that cereals should not be grown on certain plots. Copyright © 2017 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Yeh, Mei-Ling
We have performed a parallel decomposition of the fictitious Lagrangian method for molecular dynamics with tight-binding total energy expression into the hypercube computer. This is the first time in literature that the dynamical simulation of semiconducting systems containing more than 512 silicon atoms has become possible with the electrons treated as quantum particles. With the utilization of the Intel Paragon system, our timing analysis predicts that our code is expected to perform realistic simulations on very large systems consisting of thousands of atoms with time requirements of the order of tens of hours. Timing results and performance analysis of our parallel code are presented in terms of calculation time, communication time, and setup time. The accuracy of the fictitious Lagrangian method in molecular dynamics simulation is also investigated, especially the energy conservation of the total energy of ions. We find that the accuracy of the fictitious Lagrangian scheme in small silicon cluster and very large silicon system simulations is good for as long as the simulations proceed, even though we quench the electronic coordinates to the Born-Oppenheimer surface only in the beginning of the run. The kinetic energy of electrons does not increase as time goes on, and the energy conservation of the ionic subsystem remains very good. This means that, as far as the ionic subsystem is concerned, the electrons are on the average in the true quantum ground states. We also tie up some odds and ends regarding a few remaining questions about the fictitious Lagrangian method, such as the difference between the results obtained from the Gram-Schmidt and SHAKE method of orthonormalization, and differences between simulations where the electrons are quenched to the Born -Oppenheimer surface only once compared with periodic quenching.
NASA Astrophysics Data System (ADS)
Guarnieri, Daniela; Sabella, Stefania; Muscetti, Ornella; Belli, Valentina; Malvindi, Maria Ada; Fusco, Sabato; de Luca, Elisa; Pompa, Pier Paolo; Netti, Paolo A.
2014-08-01
The toxicity of metallic nanoparticles (MNPs) has been fully ascertained, but the mechanisms underlying their cytotoxicity remain still largely unclear. Here we demonstrate that the cytotoxicity of MNPs is strictly reliant on the pathway of cellular internalization. In particular, if otherwise toxic gold, silver, and iron oxide NPs are forced through the cell membrane bypassing any form of active mechanism (e.g., endocytosis), no significant cytotoxic effect is registered. Pneumatically driven NPs across the cell membrane show a different distribution within the cytosol compared to NPs entering the cell by active endocytosis. Specifically, they exhibit free random Brownian motions within the cytosol and do not accumulate in lysosomes. Results suggest that intracellular accumulation of metallic nanoparticles into endo-lysosomal compartments is the leading cause of nanotoxicity, due to consequent nanoparticle degradation and in situ release of metal ions.The toxicity of metallic nanoparticles (MNPs) has been fully ascertained, but the mechanisms underlying their cytotoxicity remain still largely unclear. Here we demonstrate that the cytotoxicity of MNPs is strictly reliant on the pathway of cellular internalization. In particular, if otherwise toxic gold, silver, and iron oxide NPs are forced through the cell membrane bypassing any form of active mechanism (e.g., endocytosis), no significant cytotoxic effect is registered. Pneumatically driven NPs across the cell membrane show a different distribution within the cytosol compared to NPs entering the cell by active endocytosis. Specifically, they exhibit free random Brownian motions within the cytosol and do not accumulate in lysosomes. Results suggest that intracellular accumulation of metallic nanoparticles into endo-lysosomal compartments is the leading cause of nanotoxicity, due to consequent nanoparticle degradation and in situ release of metal ions. Electronic supplementary information (ESI) available. See DOI: 10.1039/c4nr02008a
MIS 5e sea levels and `superstorms': what the integration of field data and modelling can tell us?
NASA Astrophysics Data System (ADS)
Rovere, A.; Raymo, M. E.; O'Leary, M.; Stocchi, P.; Vacchi, M.; Lorscheid, T.; Harris, D. L.; Casella, E.; Nandasena, N. A. K.; Sandstrom, R. M.; D'Andrea, W. J.; Dyer, B.
2016-12-01
The Last Interglacial (MIS 5e, 128-116 ka) is among the most studied past periods in Earth's history. The climate at that time was warmer than today, primarily due to different orbital conditions, with smaller ice sheets and higher sea level. Understanding the climate system, and in particular sea level, during MIS 5e is essential to understand the behavior of ice sheets in a warmer world. Two questions in particular remain unsolved: was there a meltwater pulse towards the end of the interglacial? Was the same period characterized by superstorms? Thousands of studies spanning more than a century report information on MIS 5e RSL indicators. Despite the large quantity of field data available, the two questions formulated above remain unanswered. This is due to different reasons. In first instance, relative sea-level (RSL) indicators and field interpretations may carry large uncertainties. Second, processes such as tectonics are difficult to isolate and quantify independently. In this presentation, we will describe the strategies that can be adopted to minimize the uncertainties associated with paleo RSL calculations, and we show the limits of `tectonic stability' assumptions based on the position of MIS 5e shorelines. We then show that the combination of high-resolution topographic methods (e.g. GPS, photogrammetry from UAVs and detailed bathymetry) with scenarios dictated by GIA and coastal hydrodynamic models is essential to gather insights not only on the indicative meaning of RSL indicators, but also on the hypothesis that the last period of MIS 5e was characterized by `superstorms' (as defined by Hansen, J. et al. Atmos. Chem. Phys. Discuss. 15, 2015).
Uncertainty in Climate Change Research: An Integrated Approach
NASA Astrophysics Data System (ADS)
Mearns, L.
2017-12-01
Uncertainty has been a major theme in research regarding climate change from virtually the very beginning. And appropriately characterizing and quantifying uncertainty has been an important aspect of this work. Initially, uncertainties were explored regarding the climate system and how it would react to future forcing. A concomitant area of concern was viewed in the future emissions and concentrations of important forcing agents such as greenhouse gases and aerosols. But, of course we know there are important uncertainties in all aspects of climate change research, not just that of the climate system and emissions. And as climate change research has become more important and of pragmatic concern as possible solutions to the climate change problem are addressed, exploring all the relevant uncertainties has become more relevant and urgent. More recently, over the past five years or so, uncertainties in impacts models, such as agricultural and hydrological models, have received much more attention, through programs such as AgMIP, and some research in this arena has indicated that the uncertainty in the impacts models can be as great or greater than that in the climate system. Still there remains other areas of uncertainty that remain underexplored and/or undervalued. This includes uncertainty in vulnerability and governance. Without more thoroughly exploring these last uncertainties, we likely will underestimate important uncertainties particularly regarding how different systems can successfully adapt to climate change . In this talk I will discuss these different uncertainties and how to combine them to give a complete picture of the total uncertainty individual systems are facing. And as part of this, I will discuss how the uncertainty can be successfully managed even if it is fairly large and deep. Part of my argument will be that large uncertainty is not the enemy, but rather false certainty is the true danger.
Jakobsson, R; Gustavsson, P; Lundberg, I
1997-01-01
OBJECTIVES: To study the risk of lung cancer in different subgroups of professional drivers in urban and rural areas of Sweden. METHODS: Information on occupation and geographical region was obtained from the Swedish census of 1970 and data on the incidence of lung cancer between 1971 and 1984 from the National Swedish Cancer Registry. Professional drivers were separated into bus, taxi, and long and short distance lorry drivers. Comparisons of cumulative incidence of lung cancer were made between each particular group of drivers and gainfully employed men in the same region. RESULTS: Taxi drivers, and long and short distance lorry drivers in Stockholm County showed increased relative risks (RRs) of lung cancer with the highest risk among the short distance lorry drivers (RR 2.0, 95% confidence interval (95% CI) 1.5 to 2.6). These categories of drivers also showed increased risks in the other two large conurbations in Sweden. In the rest of the country (mainly rural areas) there were no increased RRs for any category of driver. The RR for bus drivers was not increased in any region. After adjustment for assumed differences in smoking habits the RRs remained significantly increased for lorry drivers in Stockholm but not for other groups of drivers in other areas. However, the RRs remained numerically higher in large conurbations than in rural regions for all groups of drivers. CONCLUSIONS: These findings suggest that some factors present in the urban environment play a substantial part in the excess of lung cancer among short distance lorry drivers in urban areas of Sweden. Exposure to motor exhaust fumes may have contributed to this excess. PMID:9155780
Multiple origins of gigantism in stem baleen whales
NASA Astrophysics Data System (ADS)
Tsai, Cheng-Hsiu; Kohno, Naoki
2016-12-01
Living baleen whales (Mysticeti) include the world's largest animals to have ever lived—blue whales ( Balaenoptera musculus) can reach more than 30 m. However, the gigantism in baleen whales remains little explored. Here, we compiled all published stem mysticetes from the Eocene and Oligocene and then mapped the estimated body size onto different phylogenies that suggest distinct evolutionary histories of baleen whales. By assembling all known stem baleen whales, we present three novel findings in early mysticete evolution. Results show that, regardless of different phylogenetic scenarios, large body size (more than 5-m long) evolved multiple times independently in their early evolutionary history. For example, the earliest known aetiocetid ( Fucaia buelli, 33-31 Ma) was small in size, about 2 m, and a later aetiocetid ( Morawanocetus-like animal, 26-23 Ma) can reach 8-m long—almost four times the size of Fucaia buelli—suggesting an independent gigantism in the aetiocetid lineage. In addition, our reconstruction of ancestral state demonstrates that the baleen whales originated from small body size (less than 5 m) rather than large body size as previously acknowledged. Moreover, reconstructing the evolution of body size in stem baleen whales suggests that the initial pulse of mysticete gigantism started at least back to the Paleogene and in turn should help to understand the origin, pattern, and process of the extreme gigantism in the crown baleen whales. This study illustrates that Cope's rule is insufficient to explain the evolution of body size in a group that comprises the largest animals in the history of life, although currently the lack of exact ancestor-descendant relationships remains to fully reveal the evolutionary history of body size.
Multiple origins of gigantism in stem baleen whales.
Tsai, Cheng-Hsiu; Kohno, Naoki
2016-12-01
Living baleen whales (Mysticeti) include the world's largest animals to have ever lived-blue whales (Balaenoptera musculus) can reach more than 30 m. However, the gigantism in baleen whales remains little explored. Here, we compiled all published stem mysticetes from the Eocene and Oligocene and then mapped the estimated body size onto different phylogenies that suggest distinct evolutionary histories of baleen whales. By assembling all known stem baleen whales, we present three novel findings in early mysticete evolution. Results show that, regardless of different phylogenetic scenarios, large body size (more than 5-m long) evolved multiple times independently in their early evolutionary history. For example, the earliest known aetiocetid (Fucaia buelli, 33-31 Ma) was small in size, about 2 m, and a later aetiocetid (Morawanocetus-like animal, 26-23 Ma) can reach 8-m long-almost four times the size of Fucaia buelli-suggesting an independent gigantism in the aetiocetid lineage. In addition, our reconstruction of ancestral state demonstrates that the baleen whales originated from small body size (less than 5 m) rather than large body size as previously acknowledged. Moreover, reconstructing the evolution of body size in stem baleen whales suggests that the initial pulse of mysticete gigantism started at least back to the Paleogene and in turn should help to understand the origin, pattern, and process of the extreme gigantism in the crown baleen whales. This study illustrates that Cope's rule is insufficient to explain the evolution of body size in a group that comprises the largest animals in the history of life, although currently the lack of exact ancestor-descendant relationships remains to fully reveal the evolutionary history of body size.
Large scale pre-rain vegetation green up across Africa.
Adole, Tracy; Dash, Jadunandan; Atkinson, Peter M
2018-05-16
Information on the response of vegetation to different environmental drivers, including rainfall, forms a critical input to ecosystem models. Currently, such models are run based on parameters that, in some cases, are either assumed or lack supporting evidence (e.g., that vegetation growth across Africa is rainfall-driven). A limited number of studies have reported that the onset of rain across Africa does not fully explain the onset of vegetation growth, for example, drawing on the observation of pre-rain flush effects in some parts of Africa. The spatial extent of this pre-rain green-up effect, however, remains unknown, leaving a large gap in our understanding that may bias ecosystem modelling. This paper provides the most comprehensive spatial assessment to-date of the magnitude and frequency of the different patterns of phenology response to rainfall across Africa, and for different vegetation types. To define the relations between phenology and rainfall, we investigated the spatial variation in the difference, in number of days, between the start of rainy season (SRS) and start of vegetation growing season (SOS); and between the end of rainy season (ERS) and end of vegetation growing season (EOS). We reveal a much more extensive spread of pre-rain green-up over Africa than previously reported, with pre-rain green-up being the norm rather than the exception. We also show the relative sparsity of post-rain green-up, confined largely to the Sudano-Sahel region. While the pre-rain green-up phenomenon is well documented, its large spatial extent was not anticipated. Our results, thus, contrast with the widely held view that rainfall drives the onset and end of the vegetation growing season across Africa. Our findings point to a much more nuanced role of rainfall in Africa's vegetation growth cycle than previously thought, specifically as one of a set of several drivers, with important implications for ecosystem modelling. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
USDA-ARS?s Scientific Manuscript database
Background: Older adults frequently report use of vitamin and mineral (VM) supplements, though the impact of supplements on dietary adequacy remains largely unknown. Despite possible improvements in dietary intake, concern remains over potential excessive nutrient consumption from VM supplement us...
Out of School: A Phenomenological Exploration of Extended Non-Attendance
ERIC Educational Resources Information Center
Baker, Matt; Bishop, Felicity L.
2015-01-01
The concept of "extended non-attendance" ("school phobia" or "school refusal") was distinguished from truancy early in the twentieth century, and refers to children who fear school and avoid attending. Despite much subsequent research, outcomes for those affected remain poor, and their voices remain largely absent…
Distortion of calculated whole-body hematocrit during lower-body immersion in water.
Knight, D R; Santoro, T; Bondi, K R
1986-11-01
We found a difference between the venous hematocrits of immersed and nonimmersed arms during immersion of the lower body in cold water but not during a comparable exposure to warm water. Fourteen healthy men were exposed to three different experimental conditions: arm immersion, body immersion, and control. The men always sat upright while both upper extremities hung vertically at their sides. During arm immersion, one forearm was completely immersed for 30 min in either cold water (28 degrees C, n = 7) or warm water (38 degrees C, n = 7). This cold-warm water protocol was repeated on separate days for exposure to the remaining conditions of body immersion (immersion of 1 forearm and all tissues below the xiphoid process) and control (no immersion). Blood samples were simultaneously drawn from cannulated veins in both antecubital fossae. Hematocrit difference (Hct diff) was measured by subtracting the nonimmersed forearm's hematocrit (Hct dry) from the immersed forearm's hematocrit (Hct wet). Hct diff was approximately zero when the men were exposed to the control condition and body immersion in warm water. In the remaining conditions, Hct wet dropped below Hct dry (P less than 0.01, 3-way analysis of variance). The decrements of Hct diff showed there were differences between venous hematocrits in immersed and nonimmersed regions of the body, indicating that changes of the whole-body hematocrit cannot be calculated from a large-vessel hematocrit soon after immersing the lower body in cold water.
A comprehensive view of sex-specific issues related to cardiovascular disease
Pilote, Louise; Dasgupta, Kaberi; Guru, Veena; Humphries, Karin H.; McGrath, Jennifer; Norris, Colleen; Rabi, Doreen; Tremblay, Johanne; Alamian, Arsham; Barnett, Tracie; Cox, Jafna; Ghali, William Amin; Grace, Sherry; Hamet, Pavel; Ho, Teresa; Kirkland, Susan; Lambert, Marie; Libersan, Danielle; O'Loughlin, Jennifer; Paradis, Gilles; Petrovich, Milan; Tagalakis, Vicky
2007-01-01
Cardiovascular disease (CVD) is the leading cause of mortality in women. In fact, CVD is responsible for a third of all deaths of women worldwide and half of all deaths of women over 50 years of age in developing countries. The prevalence of CVD risk factor precursors is increasing in children. Retrospective analyses suggest that there are some clinically relevant differences between women and men in terms of prevalence, presentation, management and outcomes of the disease, but little is known about why CVD affects women and men differently. For instance, women with diabetes have a significantly higher CVD mortality rate than men with diabetes. Similarly, women with atrial fibrillation are at greater risk of stroke than men with atrial fibrillation. Historically, women have been underrepresented in clinical trials. The lack of good trial evidence concerning sex-specific outcomes has led to assumptions about CVD treatment in women, which in turn may have resulted in inadequate diagnoses and suboptimal management, greatly affecting outcomes. This knowledge gap may also explain why cardiovascular health in women is not improving as fast as that of men. Over the last decades, mortality rates in men have steadily declined, while those in women remained stable. It is also becoming increasingly evident that gender differences in cultural, behavioural, psychosocial and socioeconomic status are responsible, to various degrees, for the observed differences between women and men. However, the interaction between sex-and gender-related factors and CVD outcomes in women remains largely unknown. PMID:17353516
Is telomere length a molecular marker of past thermal stress in wild fish?
Debes, Paul V; Visse, Marko; Panda, Bineet; Ilmonen, Petteri; Vasemägi, Anti
2016-11-01
Telomeres protect eukaryotic chromosomes; variation in telomere length has been linked (primarily in homoeothermic animals) to variation in stress, cellular ageing and disease risk. Moreover, telomeres have been suggested to function as biomarker for quantifying past environmental stress, but studies in wild animals remain rare. Environmental stress, such as extreme environmental temperatures in poikilothermic animals, may result in oxidative stress that accelerates telomere attrition. However, growth, which may depend on temperature, can also contribute to telomere attrition. To test for associations between multitissue telomere length and past water temperature while accounting for the previous individual growth, we used quantitative PCR to analyse samples from 112 young-of-the-year brown trout from 10 natural rivers with average water temperature differences of up to 6°C (and an absolute maximum of 23°C). We found negative associations between relative telomere length (RTL) and both average river temperature and individual body size. We found no indication of RTL-temperature association differences among six tissues, but we did find indications for differences among the tissues for associations between RTL and body size; size trends, albeit nonsignificant in their differences, were strongest in muscle and weakest in fin. Although causal relationships among temperature, growth, oxidative stress, and cross-sectional telomere length remain largely unknown, our results indicate that telomere-length variation in a poikilothermic wild animal is associated with both past temperature and growth. © 2016 The Authors. Molecular Ecology Published by John Wiley & Sons Ltd.
Mathaes, Roman; Mahler, Hanns-Christian; Roggo, Yves; Huwyler, Joerg; Eder, Juergen; Fritsch, Kamila; Posset, Tobias; Mohl, Silke; Streubel, Alexander
2016-01-01
Capping equipment used in good manufacturing practice manufacturing features different designs and a variety of adjustable process parameters. The overall capping result is a complex interplay of the different capping process parameters and is insufficiently described in literature. It remains poorly studied how the different capping equipment designs and capping equipment process parameters (e.g., pre-compression force, capping plate height, turntable rotating speed) contribute to the final residual seal force of a sealed container closure system and its relation to container closure integrity and other drug product quality parameters. Stopper compression measured by computer tomography correlated to residual seal force measurements.In our studies, we used different container closure system configurations from different good manufacturing practice drug product fill & finish facilities to investigate the influence of differences in primary packaging, that is, vial size and rubber stopper design on the capping process and the capped drug product. In addition, we compared two large-scale good manufacturing practice manufacturing capping equipment and different capping equipment settings and their impact on product quality and integrity, as determined by residual seal force.The capping plate to plunger distance had a major influence on the obtained residual seal force values of a sealed vial, whereas the capping pre-compression force and the turntable rotation speed showed only a minor influence on the residual seal force of a sealed vial. Capping process parameters could not easily be transferred from capping equipment of different manufacturers. However, the residual seal force tester did provide a valuable tool to compare capping performance of different capping equipment. No vial showed any leakage greater than 10(-8)mbar L/s as measured by a helium mass spectrometry system, suggesting that container closure integrity was warranted in the residual seal force range tested for the tested container closure systems. Capping equipment used in good manufacturing practice manufacturing features different designs and a variety of adjustable process parameters. The overall capping result is a complex interplay of the different capping process parameters and is insufficiently described in the literature. It remains poorly studied how the different capping equipment designs and capping equipment process parameters contribute to the final capping result.In this study, we used different container closure system configurations from different good manufacturing process drug product fill & finish facilities to investigate the influence of the vial size and the rubber stopper design on the capping process. In addition, we compared two examples of large-scale good manufacturing process capping equipment and different capping equipment settings and their impact on product quality and integrity, as determined by residual seal force. © PDA, Inc. 2016.
Soil quality in anthropized ecosystem located in two biomes in Campinas city / SP-Brazil
NASA Astrophysics Data System (ADS)
Márcia Longo, Regina; Corcovia, Marina; Gomes, Raissa Caroline; Bettine, Sueli C.; Demamboro, Antonio Carlos; Fengler, Felipe H.; Irio Ribeiro, Admilson
2017-04-01
The rapid growth of large urban centers and the expansion of agricultural activities promote direct pressures on natural ecosystems. These actions have led to constant discussions by researchers and society as a whole in relation to preservation and quality of terrestrial ecosystems, and soil and vegetation components of vital importance to maintain these. In this context, the present study was to evaluate the anthropogenic interferences on soil properties in areas in two forest fragments located in the remaining urban areas in different biomes of Campinas-SP , Brazil. Both have their edges significantly disturbed by the proximity to urban centers , highways, sugarcane cultivation, among others. The remnant of the Atlantic Forest has an area of 250.36 ha is found in a so called protected area of ecological interest (A.R.I.E). This site access is restricted and has conservation measures, but is near major highways. The remnant of savanna has an approximate area of 40 ha there and has no conservation measure, finding it quite degraded. The physical properties and chemical soil in the two situations were collected throughout the border area totaling 28 points in the remaining savanna and 40 in the Atlantic Forest. The results were analyzed using Principal Component Analysis (PCA) to determine the main soil properties that reflect the quality of the ecosystems studied. It can be seen that most of the physical-chemical soil parameters were impacted in some way related to each other and in two ecosystems that is, the size of the vectors and the distance between them are studied in corresponding situations. The bulk density parameter has different behavior between the two biomes, since the particle density is presented close to each other but have different vector sizes. Some of the parameters have been identified with strong relationship between biomes: the Exchange Capacity Cationic (ECC) and the amounts of copper (Cu) by its close proximity of the vectors and the aluminum content (Al) and iron (Fe) for having sizes similar vectors and an appropriate distance between them. The group attributes: pH, calcium (Ca), sum of bases (SB), magnesium (Mg) and base saturation (V%) were found grouped in the two biomes but in different quadrants, reaffirming the great relationship between these parameters. Regarding the organic matter content of these they were similar in the two biomes. The higher nickel content (Ni), chromium (Cr) and lead (Pb) were found in the remaining forest, probably due to the proximity to large vehicle traffic roads. In this context, it can be concluded that the areas under study are impacted negatively in their edge areas, and components such as proximity to agricultural areas and urban sprawl, as well as proximity to major roads may be interfering with the direct mode environmental quality of forest remaining soil from two different biomes located in urban areas, and changes in levels of heavy metals and bulk density were the most affected. 1 Part of the project funded by the Foundation of the State of São Paulo Research - Brazil (FAPESP - process 2012 / 14423-8)
Comparing Ancient DNA Preservation in Petrous Bone and Tooth Cementum
Margaryan, Ashot; Stenderup, Jesper; Lynnerup, Niels; Willerslev, Eske; Allentoft, Morten E.
2017-01-01
Large-scale genomic analyses of ancient human populations have become feasible partly due to refined sampling methods. The inner part of petrous bones and the cementum layer in teeth roots are currently recognized as the best substrates for such research. We present a comparative analysis of DNA preservation in these two substrates obtained from the same human skulls, across a range of different ages and preservation environments. Both substrates display significantly higher endogenous DNA content (average of 16.4% and 40.0% for teeth and petrous bones, respectively) than parietal skull bone (average of 2.2%). Despite sample-to-sample variation, petrous bone overall performs better than tooth cementum (p = 0.001). This difference, however, is driven largely by a cluster of viking skeletons from one particular locality, showing relatively poor molecular tooth preservation (<10% endogenous DNA). In the remaining skeletons there is no systematic difference between the two substrates. A crude preservation (good/bad) applied to each sample prior to DNA-extraction predicted the above/below 10% endogenous DNA threshold in 80% of the cases. Interestingly, we observe signficantly higher levels of cytosine to thymine deamination damage and lower proportions of mitochondrial/nuclear DNA in petrous bone compared to tooth cementum. Lastly, we show that petrous bones from ancient cremated individuals contain no measurable levels of authentic human DNA. Based on these findings we discuss the pros and cons of sampling the different elements. PMID:28129388
Young, Paul E; Kum Jew, Stephen; Buckland, Michael E; Pamphlett, Roger; Suter, Catherine M
2017-01-01
Amyotrophic lateral sclerosis (ALS) is a devastating late-onset neurodegenerative disorder in which only a small proportion of patients carry an identifiable causative genetic lesion. Despite high heritability estimates, a genetic etiology for most sporadic ALS remains elusive. Here we report the epigenetic profiling of five monozygotic twin pairs discordant for ALS, four with classic ALS and one with the progressive muscular atrophy ALS variant, in whom previous whole genome sequencing failed to uncover a genetic basis for their disease discordance. By studying cytosine methylation patterns in peripheral blood DNA we identified thousands of large between-twin differences at individual CpGs. While the specific sites of differences were mostly idiosyncratic to a twin pair, a proportion involving GABA signalling were common to all ALS individuals. For both idiosyncratic and common sites the differences occurred within genes and pathways related to neurobiological functions or dysfunctions, some of particular relevance to ALS such as glutamate metabolism and the Golgi apparatus. All four classic ALS patients were epigenetically older than their unaffected co-twins, suggesting accelerated aging in multiple tissues in this disease. In conclusion, widespread changes in methylation patterns were found in ALS-affected co-twins, consistent with an epigenetic contribution to disease. These DNA methylation findings could be used to develop blood-based ALS biomarkers, gain insights into disease pathogenesis, and provide a reference for future large-scale ALS epigenetic studies.
Powell, Harry R F; Birman, Catherine S
2015-01-01
The aim of this study was to assess if large vestibular aqueduct syndrome (LVAS), with the increase in perilymphatic pressure, affects impedance changes over time with different types of Cochlear(®) implant electrode arrays Contour, Straight, and CI 422. To report speech perception outcomes for these cochlear implant recipients. Retrospective case review of impedance levels and categories of auditory performance. Impedance data were collected at switch on, 1 month, 3, 6, 12, and 24 months after cochlear implantation and compared with control (non-LVAS cochlear implant recipient) data for each array type. Forty-seven patients with exclusive LVAS and no other vestibulocochlear abnormalities or other identifiable cause of deafness were eligible for inclusion in the study. In LVAS patients, there was a significant difference in impedance between the three types of device (P < 0.0001). Time since switch on was associated with a decrease in impedance for all three devices (P < 0.0001). The mean impedance reduced between switch on and 1 month and remained relatively constant thereafter. Sound variation with softening of sounds was seen in four CI 422 (Straight Research Array) recipients due to ongoing fluctuations in electrode compliance. For all three array types, there was no significant difference in the mean impedance between the LVAS patients and controls over the first 12 months. In keeping with previous studies cochlear implant recipients with LVAS hear very well through the cochlear implant.
NASA Astrophysics Data System (ADS)
de Simone, Andrea; Franceschini, Roberto; Giudice, Gian Francesco; Pappadopulo, Duccio; Rattazzi, Riccardo
2011-05-01
It has been recently pointed out that the unavoidable tuning among supersymmetric parameters required to raise the Higgs boson mass beyond its experimental limit opens up new avenues for dealing with the so called μ- B μ problem of gauge mediation. In fact, it allows for accommodating, with no further parameter tuning, large values of B μ and of the other Higgs-sector soft masses, as predicted in models where both μ and B μ are generated at one-loop order. This class of models, called Lopsided Gauge Mediation, offers an interesting alternative to conventional gauge mediation and is characterized by a strikingly different phenomenology, with light higgsinos, very large Higgs pseudoscalar mass, and moderately light sleptons. We discuss general parametric relations involving the fine-tuning of the model and various observables such as the chargino mass and the value of tan β. We build an explicit model and we study the constraints coming from LEP and Tevatron. We show that in spite of new interactions between the Higgs and the messenger superfields, the theory can remain perturbative up to very large scales, thus retaining gauge coupling unification.
Comi, Troy J; Do, Thanh D; Rubakhin, Stanislav S; Sweedler, Jonathan V
2017-03-22
The chemical differences between individual cells within large cellular populations provide unique information on organisms' homeostasis and the development of diseased states. Even genetically identical cell lineages diverge due to local microenvironments and stochastic processes. The minute sample volumes and low abundance of some constituents in cells hinder our understanding of cellular heterogeneity. Although amplification methods facilitate single-cell genomics and transcriptomics, the characterization of metabolites and proteins remains challenging both because of the lack of effective amplification approaches and the wide diversity in cellular constituents. Mass spectrometry has become an enabling technology for the investigation of individual cellular metabolite profiles with its exquisite sensitivity, large dynamic range, and ability to characterize hundreds to thousands of compounds. While advances in instrumentation have improved figures of merit, acquiring measurements at high throughput and sampling from large populations of cells are still not routine. In this Perspective, we highlight the current trends and progress in mass-spectrometry-based analysis of single cells, with a focus on the technologies that will enable the next generation of single-cell measurements.
Role of rasagiline in treating Parkinson’s disease: Effect on disease progression
Malaty, Irene A; Fernandez, Hubert H
2009-01-01
Rasagiline is a second generation, selective, irreversible monoamine oxidase type B (MAO-B) inhibitor. It has demonstrated efficacy in monotherapy for early Parkinson’s disease (PD) patients in one large randomized, placebo-controlled trial (TVP-1012 in Early Monotherapy for Parkinson’s Disease Outpatients), and has shown ability to reduce off time in more advanced PD patients with motor fluctuations in two large placebo-controlled trials (Parkinson’s Rasagiline: Efficacy and Safety in the Treatment of “Off”, and Lasting Effect in Adjunct Therapy With Rasagiline Given Once Daily). Preclinical data abound to suggest potential for neuroprotection by this compound against a variety of neurotoxic insults in cell cultures and in animals. The lack of amphetamine metabolites provides an advantage over the first generation MAO-B inhibitor selegiline. One large trial has investigated the potential for disease modification in PD patients (Attenuation of Disease progression with Azilect Given Once-daily) and preliminary results maintain some possible advantage to earlier initiation of the 1 mg/day dose. The clinical significance of the difference detected remains a consideration. PMID:19753135
The Complete Redistribution Approximation in Optically Thick Line-Driven Winds
NASA Astrophysics Data System (ADS)
Gayley, K. G.; Onifer, A. J.
2001-05-01
Wolf-Rayet winds are thought to exhibit large momentum fluxes, which has in part been explained by ionization stratification in the wind. However, it the cause of high mass loss, not high momentum flux, that remains largely a mystery, because standard models fail to achieve sufficient acceleration near the surface where the mass-loss rate is set. We consider a radiative transfer approximation that allows for the dynamics of optically thick Wolf-Rayet winds to be modeled without detailed treatment of the radiation field, called the complete redistribution approximation. In it, it is assumed that thermalization processes cause the photon frequencies to be completely randomized over the course of propagating through the wind, which allows the radiation field to be treated statistically rather than in detail. Thus the approach is similar to the statistical treatment of the line list used in the celebrated CAK approach. The results differ from the effectively gray treatment in that the radiation field is influenced by the line distribution, and the role of gaps in the line distribution is enhanced. The ramifications for the driving of large mass-loss rates is explored.
Landa, M; Cottrell, M T; Kirchman, D L; Kaiser, K; Medeiros, P M; Tremblay, L; Batailler, N; Caparros, J; Catala, P; Escoubeyrou, K; Oriol, L; Blain, S; Obernosterer, I
2014-06-01
Dissolved organic matter (DOM) and heterotrophic bacteria are highly diverse components of the ocean system, and their interactions are key in regulating the biogeochemical cycles of major elements. How chemical and phylogenetic diversity are linked remains largely unexplored to date. To investigate interactions between bacterial diversity and DOM, we followed the response of natural bacterial communities to two sources of phytoplankton-derived DOM over six bacterial generation times in continuous cultures. Analyses of total hydrolysable neutral sugars and amino acids, and ultrahigh resolution mass spectrometry revealed large differences in the chemical composition of the two DOM sources. According to 454 pyrosequences of 16S ribosomal ribonucleic acid genes, diatom-derived DOM sustained higher levels of bacterial richness, evenness and phylogenetic diversity than cyanobacteria-derived DOM. These distinct community structures were, however, not associated with specific taxa. Grazing pressure affected bacterial community composition without changing the overall pattern of bacterial diversity levels set by DOM. Our results demonstrate that resource composition can shape several facets of bacterial diversity without influencing the phylogenetic composition of bacterial communities, suggesting functional redundancy at different taxonomic levels for the degradation of phytoplankton-derived DOM. © 2013 Society for Applied Microbiology and John Wiley & Sons Ltd.
Determining the energetic and informational components of speech-on-speech masking
Kidd, Gerald; Mason, Christine R.; Swaminathan, Jayaganesh; Roverud, Elin; Clayton, Kameron K.; Best, Virginia
2016-01-01
Identification of target speech was studied under masked conditions consisting of two or four independent speech maskers. In the reference conditions, the maskers were colocated with the target, the masker talkers were the same sex as the target, and the masker speech was intelligible. The comparison conditions, intended to provide release from masking, included different-sex target and masker talkers, time-reversal of the masker speech, and spatial separation of the maskers from the target. Significant release from masking was found for all comparison conditions. To determine whether these reductions in masking could be attributed to differences in energetic masking, ideal time-frequency segregation (ITFS) processing was applied so that the time-frequency units where the masker energy dominated the target energy were removed. The remaining target-dominated “glimpses” were reassembled as the stimulus. Speech reception thresholds measured using these resynthesized ITFS-processed stimuli were the same for the reference and comparison conditions supporting the conclusion that the amount of energetic masking across conditions was the same. These results indicated that the large release from masking found under all comparison conditions was due primarily to a reduction in informational masking. Furthermore, the large individual differences observed generally were correlated across the three masking release conditions. PMID:27475139
Mu, Da-Shuai; Li, Chenyang; Shi, Liang; Zhang, Xuchen; Ren, Ang; Zhao, Ming-Wen
2015-01-01
MicroRNAs (miRNAs) are a class of small, endogenous, noncoding RNA molecules that negatively regulate gene expression at the transcriptional or the post-transcriptional level. Although a large number of miRNAs have been identified in many species, especially model plants and animals, miRNAs in fungi remain largely unknown. In this study, based on a database of expressed sequence tags in Ganoderma lucidum, 89 potential miRNAs were identified using computational methods. Real-time polymerase chain reaction analysis of miRNA-like samples prepared from G. lucidum at different development stages revealed that miRNA-like RNAs were differentially expressed in different stages. Furthermore, a total of 28 potential targets were found based on near-perfect or perfect complementarity between the randomly selected 9 miRNA-like RNAs and the target sequences, and potential targets for G. lucidum miRNA-like RNAs were predicted. Finally, we studied the expression pattern of 4 target genes in 3 different development stages of G. lucidum to further understand the mechanism of interaction between miRNA-like RNAs and their target genes. Our analysis paves the way toward identifying fungal miRNA-like RNAs that might be involved in various physiological and cellular differentiation processes.
NASA Astrophysics Data System (ADS)
Arnaud, F.; Piégay, H.; Vaudor, L.; Bultingaire, L.; Fantino, G.
2015-06-01
Low-frequency passive integrated transponders (PIT tags) have been increasingly used for tracking bedload transport in gravel-bed rivers. Prior studies have reported high recovery rates in small streams, while recovery rates remained much lower in large systems, in large part because of the limited reading distance of the tags (< 1 m). Some laboratory tests have identified controlling factors for detection ranges (tag and antenna size, tag orientation, burial, submergence, etc.). Beyond these tests, improving our understanding of PIT tag functioning, using different equipment within different environments, is still needed in order to select the most suitable device for each geomorphic context. We address this knowledge gap with technical specifications for a low-frequency radio identification (RFID) device by working for the first time with real fluvial constraints, i.e., the gravel deposits and the aquatic channel. The three-dimensional detection envelopes of two types of tags and three types of antennas are quantified as well as the effect of practices (interoperator bias, battery power) on the detection. The interoperator variability and the intertag variability can be considered as negligible. The influence of burial in dry and water-saturated sediment and the influence of water immersion are shown to be minor. Finally, we summarize practical implications for RFID bedload tracking through these experiments.
Janis, Brett; Uversky, Vladimir N; Menze, Michael A
2017-10-23
Late embryogenesis abundant (LEA) proteins are a large group of anhydrobiosis-associated intrinsically disordered proteins, which are commonly found in plants and some animals. The brine shrimp Artemia franciscana is the only known animal that expresses LEA proteins from three, and not only one, different groups in its anhydrobiotic life stage. The reason for the higher complexity in the A. franciscana LEA proteome (LEAome), compared with other anhydrobiotic animals, remains mostly unknown. To address this issue, we have employed a suite of bioinformatics tools to evaluate the disorder status of the Artemia LEAome and to analyze the roles of intrinsic disorder in functioning of brine shrimp LEA proteins. We show here that A. franciscana LEA proteins from different groups are more similar to each other than one originally expected, while functional differences among members of group three are possibly larger than commonly anticipated. Our data show that although these proteins are characterized by a large variety of forms and possible functions, as a general strategy, A. franciscana utilizes glassy matrix forming LEAs concurrently with proteins that more readily interact with binding partners. It is likely that the function(s) of both types, the matrix-forming and partner-binding LEA proteins, are regulated by changing water availability during desiccation.
Towards a Viscous Wall Model for Immersed Boundary Methods
NASA Technical Reports Server (NTRS)
Brehm, Christoph; Barad, Michael F.; Kiris, Cetin C.
2016-01-01
Immersed boundary methods are frequently employed for simulating flows at low Reynolds numbers or for applications where viscous boundary layer effects can be neglected. The primary shortcoming of Cartesian mesh immersed boundary methods is the inability of efficiently resolving thin turbulent boundary layers in high-Reynolds number flow application. The inefficiency of resolving the thin boundary is associated with the use of constant aspect ratio Cartesian grid cells. Conventional CFD approaches can efficiently resolve the large wall normal gradients by utilizing large aspect ratio cells near the wall. This paper presents different approaches for immersed boundary methods to account for the viscous boundary layer interaction with the flow-field away from the walls. Different wall modeling approaches proposed in previous research studies are addressed and compared to a new integral boundary layer based approach. In contrast to common wall-modeling approaches that usually only utilize local flow information, the integral boundary layer based approach keeps the streamwise history of the boundary layer. This allows the method to remain effective at much larger y+ values than local wall modeling approaches. After a theoretical discussion of the different approaches, the method is applied to increasingly more challenging flow fields including fully attached, separated, and shock-induced separated (laminar and turbulent) flows.
Role of passive deformation on propulsion through a lumped torsional flexibility model
NASA Astrophysics Data System (ADS)
Arora, Nipun; Gupta, Amit
2016-11-01
Scientists and biologists have been affianced in a deeper examination of insect flight to develop an improved understanding of the role of flexibility on aerodynamic performance. Here, we mimic a flapping wing through a fluid-structure interaction framework based upon a lumped torsional flexibility model. The developed fluid and structural solvers together determine the aerodynamic forces and wing deformation, respectively. An analytical solution to the simplified single-spring structural dynamics equation is established to substantiate simulations. It is revealed that the dynamics of structural deformation is governed by the balance between inertia, stiffness and aerodynamics, where the former two oscillate at the plunging frequency and the latter oscillates at twice the plunging frequency. We demonstrate that an induced phase difference between plunging and passive pitching is responsible for a higher thrust coefficient. This phase difference is also shown to be dependent on aerodynamics to inertia and natural to plunging frequency ratios. For inertia dominated flows, pitching and plunging always remain in phase. As the aerodynamics dominates, a large phase difference is induced which is accountable for a large passive deformation and higher thrust. Authors acknowledge the financial support received from the Aeronautics Research and Development Board (ARDB) under SIGMA Project No. 1705 and thank the IIT Delhi HPC facility for computational resources.
Sakamoto, Kana; Nakasone, Hideki; Togashi, Yuki; Sakata, Seiji; Tsuyama, Naoko; Baba, Satoko; Dobashi, Akito; Asaka, Reimi; Tsai, Chien-Chen; Chuang, Shih-Sung; Izutsu, Koji; Kanda, Yoshinobu; Takeuchi, Kengo
2016-04-01
Anaplastic lymphoma kinase-positive large B-cell lymphoma (ALK+LBCL) is a rare, aggressive B-cell lymphoma with ALK fusion genes. Histopathologically, the ALK immunohistochemical staining pattern is suggestive of the fusion partner of ALK. Here, we examined an ALK+LBCL case showing a unique diffuse cytoplasmic ALK staining pattern and identified EML4-ALK, which has not previously been reported in ALK+LBCL. Furthermore, to clarify whether the prognosis differs depending on the staining pattern, we reviewed 112 previously reported cases, and analyzed immunohistochemical markers and clinical data stratified by the staining pattern. We found that ALK staining can be classified into a granular cytoplasmic staining (GCS) or a non-GCS patterns. Sixty-four adult cases for which both the ALK staining pattern and survival time were reported were further analyzed for survival trends. The non-GCS pattern was significantly associated with inferior overall survival (P = 0.031). This difference remained significant after adjusting for age and clinical stage (hazard ratio 5.08, 95 % CI 1.88-13.7, P = 0.0013). Given that the ALK immunohistochemical staining pattern is associated with the ALK fusion partner, the present results suggest that the prognosis for ALK+LBCL differs depending on the ALK fusion partner.
Hierarchical Context Modeling for Video Event Recognition.
Wang, Xiaoyang; Ji, Qiang
2016-10-11
Current video event recognition research remains largely target-centered. For real-world surveillance videos, targetcentered event recognition faces great challenges due to large intra-class target variation, limited image resolution, and poor detection and tracking results. To mitigate these challenges, we introduced a context-augmented video event recognition approach. Specifically, we explicitly capture different types of contexts from three levels including image level, semantic level, and prior level. At the image level, we introduce two types of contextual features including the appearance context features and interaction context features to capture the appearance of context objects and their interactions with the target objects. At the semantic level, we propose a deep model based on deep Boltzmann machine to learn event object representations and their interactions. At the prior level, we utilize two types of prior-level contexts including scene priming and dynamic cueing. Finally, we introduce a hierarchical context model that systematically integrates the contextual information at different levels. Through the hierarchical context model, contexts at different levels jointly contribute to the event recognition. We evaluate the hierarchical context model for event recognition on benchmark surveillance video datasets. Results show that incorporating contexts in each level can improve event recognition performance, and jointly integrating three levels of contexts through our hierarchical model achieves the best performance.
Computational time analysis of the numerical solution of 3D electrostatic Poisson's equation
NASA Astrophysics Data System (ADS)
Kamboh, Shakeel Ahmed; Labadin, Jane; Rigit, Andrew Ragai Henri; Ling, Tech Chaw; Amur, Khuda Bux; Chaudhary, Muhammad Tayyab
2015-05-01
3D Poisson's equation is solved numerically to simulate the electric potential in a prototype design of electrohydrodynamic (EHD) ion-drag micropump. Finite difference method (FDM) is employed to discretize the governing equation. The system of linear equations resulting from FDM is solved iteratively by using the sequential Jacobi (SJ) and sequential Gauss-Seidel (SGS) methods, simulation results are also compared to examine the difference between the results. The main objective was to analyze the computational time required by both the methods with respect to different grid sizes and parallelize the Jacobi method to reduce the computational time. In common, the SGS method is faster than the SJ method but the data parallelism of Jacobi method may produce good speedup over SGS method. In this study, the feasibility of using parallel Jacobi (PJ) method is attempted in relation to SGS method. MATLAB Parallel/Distributed computing environment is used and a parallel code for SJ method is implemented. It was found that for small grid size the SGS method remains dominant over SJ method and PJ method while for large grid size both the sequential methods may take nearly too much processing time to converge. Yet, the PJ method reduces computational time to some extent for large grid sizes.
Spatial structure and distribution of small pelagic fish in the northwestern Mediterranean Sea.
Saraux, Claire; Fromentin, Jean-Marc; Bigot, Jean-Louis; Bourdeix, Jean-Hervé; Morfin, Marie; Roos, David; Van Beveren, Elisabeth; Bez, Nicolas
2014-01-01
Understanding the ecological and anthropogenic drivers of population dynamics requires detailed studies on habitat selection and spatial distribution. Although small pelagic fish aggregate in large shoals and usually exhibit important spatial structure, their dynamics in time and space remain unpredictable and challenging. In the Gulf of Lions (north-western Mediterranean), sardine and anchovy biomasses have declined over the past 5 years causing an important fishery crisis while sprat abundance rose. Applying geostatistical tools on scientific acoustic surveys conducted in the Gulf of Lions, we investigated anchovy, sardine and sprat spatial distributions and structures over 10 years. Our results show that sardines and sprats were more coastal than anchovies. The spatial structure of the three species was fairly stable over time according to variogram outputs, while year-to-year variations in kriged maps highlighted substantial changes in their location. Support for the McCall's basin hypothesis (covariation of both population density and presence area with biomass) was found only in sprats, the most variable of the three species. An innovative method to investigate species collocation at different scales revealed that globally the three species strongly overlap. Although species often co-occurred in terms of presence/absence, their biomass density differed at local scale, suggesting potential interspecific avoidance or different sensitivity to local environmental characteristics. Persistent favourable areas were finally detected, but their environmental characteristics remain to be determined.
Martin, K; Gertler, R; MacGuill, M; Mayr, N P; Hapfelmeier, A; Hörer, J; Vogt, M; Tassani, P; Wiesner, G
2013-04-01
Once aprotinin was no longer available for clinical use, ε-aminocaproic acid (EACA) and tranexamic acid became the only two options for antifibrinolytic therapy. We compared aprotinin and EACA with respect to their blood-sparing efficacy and other major clinical outcome criteria in infants undergoing cardiac surgery. We retrospectively analysed data from a large consecutive cohort of infants (n=227) aged 31-365 days undergoing primary cardiac surgery requiring cardiopulmonary bypass encompassing the transition from aprotinin to EACA (aprotinin n=88, EACA n=139); all other aspects including the medical team and departmental protocols remained unchanged. The primary outcome was postoperative blood loss measured as chest tube output (CTO). Secondary outcome parameters were transfusion requirements, reoperation due to bleeding, renal, vascular, and neurological complications, and in-hospital mortality. CTO was significantly higher in the EACA patients {aprotinin 18 (13-27) ml kg(-1) 24 h(-1), EACA 23 (15-37) ml kg(-1) 24 h(-1) [mean (inter-quartile range)], P=0.001}, but transfusion requirements and donor exposures were not significantly different. A sensitivity analysis strengthened our finding that the increased blood loss in the EACA group was attributable to lower efficacy of EACA. There were no significant differences in the other clinical outcome measures. CTO was lower in aprotinin-treated patients. Nonetheless, EACA remains a suitable substitute without measurable differences in other clinical outcome criteria.
NASA Astrophysics Data System (ADS)
Li, Wei; Alves, Tiago M.; Wu, Shiguo; Rebesco, Michele; Zhao, Fang; Mi, Lijun; Ma, Benjun
2016-10-01
A giant submarine creep zone exceeding 800 km2 on the continental slope offshore the Dongsha Islands, South China Sea, is investigated using bathymetric and 3D seismic data tied to borehole information. The submarine creep zone is identified as a wide area of seafloor undulations with ridges and troughs. The troughs form NW- and WNW-trending elongated depressions separating distinct seafloor ridges, which are parallel or sub-parallel to the continental slope. The troughs are 0.8-4.7 km-long and 0.4 to 2.1 km-wide. The ridges have wavelengths of 1-4 km and vertical relief of 10-30 m. Slope strata are characterised by the presence of vertically stacked ridges and troughs at different stratigraphic depths, but remaining relatively stationary in their position. The interpreted ridges and troughs are associated with large-scale submarine creep, and the troughs can be divided into three types based on their different internal characters and formation processes. The large-scale listric faults trending downslope below MTD 1 and horizon T0 may be the potential glide planes for the submarine creep movement. High sedimentation rates, local fault activity and the frequent earthquakes recorded on the margin are considered as the main factors controlling the formation of this giant submarine creep zone. Our results are important to the understanding of sediment instability on continental slopes as: a) the interpreted submarine creep is young, or even active at present, and b) areas of creeping may evolve into large-scale slope instabilities, as recorded by similar large-scale events in the past.
A comparison of large 18th-century floods on Danube: Vienna - Bratislava - Budapest
NASA Astrophysics Data System (ADS)
Kiss, Andrea; Parajka, Juraj
2013-04-01
The documentation of historic floods can help in better understanding of factors that might cause and contribute to large and extreme flood events. In particular, the analysis of historic floods provides information about flood seasonality, its changes and anthropogenic impacts on river flood regime which in some cases strongly influenced flood behaviour. The main objective of the present contribution is to document large and medium size flood events on Danube in Vienna, Bratislava and Budapest in the 18th century. In the present study, based on contemporary documentary evidence, for each of the three towns a five-scaled flood index series is developed to describe the magnitude and intensity of flood events. According to this classification, the 100-year flood event was characterised by the index value 5, while great destructive floods - depending on their extension, destructivity and further impacts - received the values 4 and 3, respectively. Less significant but still harmful flood events were classified as No. 2, and floods without further specification remained in the lowest category (No. 1). Beside classification issues, seasonality and flood frequency differences between the three towns are as well discussed. The results indicate that a greater number of flood events took place in the last decades of the century, but only a few flood events of the same magnitude are documented simultaneously in all three towns. And whereas in 1775 no winter flood event was reported in Vienna, an important ice jam flood was documented in Bratislava, and a catastrophic ice jam flood event, greatest of the century, occurred in Budapest. In 1787 autumn the greatest flood event of the century occurred in Vienna, while hardly any flood waves were observed at Budapest. While in Vienna, summer (and partly autumn) floods had great importance, in Budapest a large number of ice jam floods were documented. In some cases the differences are likely caused by different hydrometeorological and morphological conditions, but the importance of human impact (e.g. different types and levels of flood protection in the towns, large-scale changes of land use in the catchment area) have to be as well emphasised.
Synergistic Measurement of Ice Cloud Microphysics using C- and Ka-Band Radars
NASA Astrophysics Data System (ADS)
Ewald, F.; Gross, S.; Hagen, M.; Li, Q.; Zinner, T.
2017-12-01
Ice clouds play an essential role in the climate system since they have a large effect on the Earth's radiation budget. Uncertainties associated with their spatial and temporal distribution as well as their optical and microphysical properties still account for large uncertainties in climate change predictions. Substantial improvement of our understanding of ice clouds was achieved with the advent of cloud radars into the field of ice cloud remote sensing. Here, highly variable ice crystal size distributions are one of the key issues remaining to be resolved. With radar reflectivity scaling with the sixth moment of the particle size, the assumed ice crystal size distribution has a large impact on the results of microphysical retrievals. Different ice crystal sizes distributions can, however, be distinguished, when cloud radars of different wavelength are used simultaneously.For this study, synchronous RHI scans were performed for a common measurement range of about 30 km between two radar instruments using different wavelengths: the dual-polarization C-band radar POLDIRAD operated at DLR and the Mira-36 Ka-band cloud radar operated at the University of Munich. For a measurement period over several months, the overlapping region for ice clouds turned out to be quite large. This gives evidence on the presence of moderate-sized ice crystals for which the backscatter is sufficient high to be visible in the C-band as well. In the range between -10 to +10 dBz, reflectivity measurements from both radars agreed quite well indicating the absence of large ice crystals. For reflectivities above +10 dBz, we observed differences with smaller values at the Ka-band due to Mie scattering effects at larger ice crystals.In this presentation, we will show how this differential reflectivity can be used to gain insight into ice cloud microphysics on the basis of electromagnetic scattering calculations. We will further explore ice cloud microphysics using the full polarization agility of the C-band radar and compare the results to simultaneous linear depolarization measurements with the Ka-band radar. In summary, we will explore if the scientific understanding of ice cloud microphysics can be advanced by the combination of C- and Ka-band radars.
Higgins, Denice; Rohrlach, Adam B.; Kaidonis, John; Townsend, Grant; Austin, Jeremy J.
2015-01-01
Major advances in genetic analysis of skeletal remains have been made over the last decade, primarily due to improvements in post-DNA-extraction techniques. Despite this, a key challenge for DNA analysis of skeletal remains is the limited yield of DNA recovered from these poorly preserved samples. Enhanced DNA recovery by improved sampling and extraction techniques would allow further advancements. However, little is known about the post-mortem kinetics of DNA degradation and whether the rate of degradation varies between nuclear and mitochondrial DNA or across different skeletal tissues. This knowledge, along with information regarding ante-mortem DNA distribution within skeletal elements, would inform sampling protocols facilitating development of improved extraction processes. Here we present a combined genetic and histological examination of DNA content and rates of DNA degradation in the different tooth tissues of 150 human molars over short-medium post-mortem intervals. DNA was extracted from coronal dentine, root dentine, cementum and pulp of 114 teeth via a silica column method and the remaining 36 teeth were examined histologically. Real time quantification assays based on two nuclear DNA fragments (67 bp and 156 bp) and one mitochondrial DNA fragment (77 bp) showed nuclear and mitochondrial DNA degraded exponentially, but at different rates, depending on post-mortem interval and soil temperature. In contrast to previous studies, we identified differential survival of nuclear and mtDNA in different tooth tissues. Futhermore histological examination showed pulp and dentine were rapidly affected by loss of structural integrity, and pulp was completely destroyed in a relatively short time period. Conversely, cementum showed little structural change over the same time period. Finally, we confirm that targeted sampling of cementum from teeth buried for up to 16 months can provide a reliable source of nuclear DNA for STR-based genotyping using standard extraction methods, without the need for specialised equipment or large-volume demineralisation steps. PMID:25992635
Verbal learning changes in older adults across 18 months.
Zimprich, Daniel; Rast, Philippe
2009-07-01
The major aim of this study was to investigate individual changes in verbal learning across a period of 18 months. Individual differences in verbal learning have largely been neglected in the last years and, even more so, individual differences in change in verbal learning. The sample for this study comes from the Zurich Longitudinal Study on Cognitive Aging (ZULU; Zimprich et al., 2008a) and comprised 336 older adults in the age range of 65-80 years at first measurement occasion. In order to address change in verbal learning we used a latent change model of structured latent growth curves to account for the non-linearity of the verbal learning data. The individual learning trajectories were captured by a hyperbolic function which yielded three psychologically distinct parameters: initial performance, learning rate, and asymptotic performance. We found that average performance increased with respect to initial performance, but not in learning rate or in asymptotic performance. Further, variances and covariances remained stable across both measurement occasions, indicating that the amount of individual differences in the three parameters remained stable, as did the relationships among them. Moreover, older adults differed reliably in their amount of change in initial performance and asymptotic performance. Eventually, changes in asymptotic performance and learning rate were strongly negatively correlated. It thus appears as if change in verbal learning in old age is a constrained process: an increase in total learning capacity implies that it takes longer to learn. Together, these results point to the significance of individual differences in change of verbal learning in the elderly.
Vidal, Sarah; Steeger, Christine M; Caron, Colleen; Lasher, Leanne; Connell, Christian M
2017-11-01
Multisystemic therapy (MST) was developed to help youth with serious social, emotional, and behavioral problems. Research on the efficacy and effectiveness of MST has shown positive outcomes in different domains of development and functioning among various populations of youth. Nonetheless, even with a large body of literature investigating the treatment effects of MST, few studies have focused on the effectiveness of MST through large-scale dissemination efforts. Utilizing a large sample of youth involved in a statewide dissemination of MST (n = 740; 43% females; 14% Black; 29% Hispanic; 49% White; M age = 14.9 years), propensity score matching was employed to account for baseline differences between the treatment (n = 577) and comparison (n = 163) groups. Treatment effects were examined based on three outcomes: out-of-home placement, adjudication, and placement in a juvenile training school over a 6-year period. Significant group differences remained after adjusting for baseline differences, with youth who received MST experiencing better outcomes in offending rates than youth who did not have an opportunity to complete MST due to non-clinical or administrative reasons. Survival analyses revealed rates of all three outcomes were approximately 40% lower among the treatment group. Overall, this study adds to the body of literature supporting the long-term effectiveness of MST in reducing offending among high-risk youth. The findings underscore the potential benefits of taking evidence-based programs such as MST to scale to improve the well-being and functioning of high-risk youth. However, strategies to effectively deliver the program in mental health service settings, and to address the specific needs of high-risk youth are necessary.
Atypical sulcal anatomy in young children with autism spectrum disorder
Auzias, G.; Viellard, M.; Takerkart, S.; Villeneuve, N.; Poinso, F.; Fonséca, D. Da; Girard, N.; Deruelle, C.
2014-01-01
Autism spectrum disorder is associated with an altered early brain development. However, the specific cortical structure abnormalities underlying this disorder remain largely unknown. Nonetheless, atypical cortical folding provides lingering evidence of early disruptions in neurodevelopmental processes and identifying changes in the geometry of cortical sulci is of primary interest for characterizing these structural abnormalities in autism and their evolution over the first stages of brain development. Here, we applied state-of-the-art sulcus-based morphometry methods to a large highly-selective cohort of 73 young male children of age spanning from 18 to 108 months. Moreover, such large cohort was selected through extensive behavioral assessments and stringent inclusion criteria for the group of 59 children with autism. After manual labeling of 59 different sulci in each hemisphere, we computed multiple shape descriptors for each single sulcus element, hereby separating the folding measurement into distinct factors such as the length and depth of the sulcus. We demonstrated that the central, intraparietal and frontal medial sulci showed a significant and consistent pattern of abnormalities across our different geometrical indices. We also found that autistic and control children exhibited strikingly different relationships between age and structural changes in brain morphology. Lastly, the different measures of sulcus shapes were correlated with the CARS and ADOS scores that are specific to the autistic pathology and indices of symptom severity. Inherently, these structural abnormalities are confined to regions that are functionally relevant with respect to cognitive disorders in ASD. In contrast to those previously reported in adults, it is very unlikely that these abnormalities originate from general compensatory mechanisms unrelated to the primary pathology. Rather, they most probably reflect an early disruption on developmental trajectory that could be part of the primary pathology. PMID:24936410
Baxter, S W; Hoffman, J I; Tregenza, T; Wedell, N; Hosken, D J
2017-01-01
Understanding selection in the wild remains a major aim of evolutionary ecology and work by Ford and colleagues on the meadow brown butterfly Maniola jurtina did much to ignite this agenda. A great deal of their work was conducted during the 1950s on the Isles of Scilly. They documented island-specific wing-spot patterns that remained consistent over about a decade, but patterns on some islands changed after environmental perturbation. It was suggested that these wing-spot patterns reflected island-specific selection and that there was little migration between islands. However, genetic studies to test the underlying assumption of restricted migration are lacking and it is also unknown whether the originally described wing-spot patterns have persisted over time. We therefore collected female butterflies from five of Ford's original study locations, including three large islands (St Mary's, St Martin's and Tresco) and two small islands (Tean and St Helen's). Wing-spot patterns had not changed appreciably over time on three of the islands (two large and one small), but were significantly different on the other two. Furthermore, analysis of 176 amplified fragment length polymorphisms revealed significant genome-wide differentiation among the five islands. Our findings are consistent with Ford's conclusions that despite the close proximity of these islands, there is restricted gene flow among them. PMID:27804964
Fraiman, Daniel; Chialvo, Dante R.
2012-01-01
The study of spontaneous fluctuations of brain activity, often referred as brain noise, is getting increasing attention in functional magnetic resonance imaging (fMRI) studies. Despite important efforts, much of the statistical properties of such fluctuations remain largely unknown. This work scrutinizes these fluctuations looking at specific statistical properties which are relevant to clarify its dynamical origins. Here, three statistical features which clearly differentiate brain data from naive expectations for random processes are uncovered: First, the variance of the fMRI mean signal as a function of the number of averaged voxels remains constant across a wide range of observed clusters sizes. Second, the anomalous behavior of the variance is originated by bursts of synchronized activity across regions, regardless of their widely different sizes. Finally, the correlation length (i.e., the length at which the correlation strength between two regions vanishes) as well as mutual information diverges with the cluster's size considered, such that arbitrarily large clusters exhibit the same collective dynamics than smaller ones. These three properties are known to be exclusive of complex systems exhibiting critical dynamics, where the spatio-temporal dynamics show these peculiar type of fluctuations. Thus, these findings are fully consistent with previous reports of brain critical dynamics, and are relevant for the interpretation of the role of fluctuations and variability in brain function in health and disease. PMID:22934058
Enabling large-scale forest restoration in Minas Gerais state, Brazil
NASA Astrophysics Data System (ADS)
Nunes, Felipe S. M.; Soares-Filho, Britaldo S.; Rajão, Raoni; Merry, Frank
2017-04-01
Large-scale forest restoration is a cornerstone of Brazil’s new Forest Code and a key element in its National Determined Contribution (NDC) to emissions reduction. But the path to this target remains unclear due to a lack of information on its economics and implementation challenges. Here, we begin to fill this gap by developing a spatially-explicit model for Minas Gerais state that estimates the costs and benefits of native vegetation regeneration under different restoration approaches. Our results show that 36% (0.7 million ha) of the Forest Code debt in Minas Gerais can be restored using only passive restoration, at a cost of US 175 ± 47 million. Adding low-cost assisted natural regeneration would increase that number to 75% (1.5 million ha) at a cost of US 776 ± 137 million over a 20 yr period. This would result in a potential sequestration of 284 MtCO2e. However, including the intensive planting methods needed to restore the remaining 25% of highly degraded areas—to fully solve the Forest Code debt and result in a potential sequestration of 345 MtCO2e—would more than double the costs to US 1.7 ± 0.3 billion. Our results emphasize the need to implement regional policies that take advantage of the natural regeneration potential as well as prioritize the restoration of areas key to ecosystem services.
Direct quantification of rare earth doped titania nanoparticles in individual human cells
NASA Astrophysics Data System (ADS)
Jeynes, J. C. G.; Jeynes, C.; Palitsin, V.; Townley, H. E.
2016-07-01
There are many possible biomedical applications for titania nanoparticles (NPs) doped with rare earth elements (REEs), from dose enhancement and diagnostic imaging in radiotherapy, to biosensing. However, there are concerns that the NPs could disintegrate in the body thus releasing toxic REE ions to undesired locations. As a first step, we investigate how accurately the Ti/REE ratio from the NPs can be measured inside human cells. A quantitative analysis of whole, unsectioned, individual human cells was performed using proton microprobe elemental microscopy. This method is unique in being able to quantitatively analyse all the elements in an unsectioned individual cell with micron resolution, while also scanning large fields of view. We compared the Ti/REE signal inside cells to NPs that were outside the cells, non-specifically absorbed onto the polypropylene substrate. We show that the REE signal in individual cells co-localises with the titanium signal, indicating that the NPs have remained intact. Within the uncertainty of the measurement, there is no difference between the Ti/REE ratio inside and outside the cells. Interestingly, we also show that there is considerable variation in the uptake of the NPs from cell-to-cell, by a factor of more than 10. We conclude that the NPs enter the cells and remain intact. The large heterogeneity in NP concentrations from cell-to-cell should be considered if they are to be used therapeutically.
NASA Astrophysics Data System (ADS)
Morrison, Ross; Balzter, Heiko; Burden, Annette; Callaghan, Nathan; Cumming, Alenander; Dixon, Simon; Evans, Jonathan; Kaduk, Joerg; Page, Susan; Pan, Gong; Rayment, Mark; Ridley, Luke; Rylett, Daniel; Worrall, Fred; Evans, Christopher
2016-04-01
Peatlands store disproportionately large amounts of soil carbon relative to other terrestrial ecosystems. Over recent decades, the large amount of carbon stored as peat has proved vulnerable to a range of land use pressures as well as the increasing impacts of climate change. In temperate Europe and elsewhere, large tracts of lowland peatland have been drained and converted to agricultural land use. Such changes have resulted in widespread losses of lowland peatland habitat, land subsidence across extensive areas and the transfer of historically accumulated soil carbon to the atmosphere as carbon dioxide (CO2). More recently, there has been growth in activities aiming to reduce these impacts through improved land management and peatland restoration. Despite a long history of productive land use and management, the magnitude and controls on greenhouse gas emissions from lowland peatland environments remain poorly quantified. Here, results of surface-atmosphere measurements of net ecosystem CO2 exchange (NEE) from a network of seven eddy covariance (EC) flux towers located at a range of lowland peatland ecosystems across the United Kingdom (UK) are presented. This spatially-dense peatland flux tower network forms part of a wider observation programme aiming to quantify carbon, water and greenhouse gas balances for lowland peatlands across the UK. EC measurements totalling over seventeen site years were obtained at sites exhibiting large differences in vegetation cover, hydrological functioning and land management. The sites in the network show remarkable spatial and temporal variability in NEE. Across sites, annual NEE ranged from a net sink of -194 ±38 g CO2-C m-2 yr-1 to a net source of 784±70 g CO2-C m-2 yr-1. The results suggest that semi-natural sites remain net sinks for atmospheric CO2. Sites that are drained for intensive agricultural production range from a small net sink to the largest observed source for atmospheric CO2 within the flux tower network. Extensively managed grassland and a site that was restored from intensive arable land use represent modest CO2 sources. Temporal variations in CO2 fluxes at sites with permanent vegetation cover are coupled to seasonal and interannual variations in weather conditions and phenology. The type of crop produced and agricultural management drive large temporal differences in the CO2 fluxes of croplands on drained lowland peat soils. The main environmental controls on the spatial and temporal variations in CO2 exchange processes will be discussed.
Body size in early life and risk of breast cancer.
Shawon, Md Shajedur Rahman; Eriksson, Mikael; Li, Jingmei
2017-07-21
Body size in early life is inversely associated with adult breast cancer (BC) risk, but it is unclear whether the associations differ by tumor characteristics. In a pooled analysis of two Swedish population-based studies consisting of 6731 invasive BC cases and 28,705 age-matched cancer-free controls, we examined the associations between body size in early life and BC risk. Self-reported body sizes at ages 7 and 18 years were collected by a validated nine-level pictogram (aggregated into three categories: small, medium and large). Odds ratios (OR) and corresponding 95% confidence intervals (CI) were estimated from multivariable logistic regression models in case-control analyses, adjusting for study, age at diagnosis, age at menarche, number of children, hormone replacement therapy, and family history of BC. Body size change between ages 7 and 18 were also examined in relation to BC risk. Case-only analyses were performed to test whether the associations differed by tumor characteristics. Medium or large body size at age 7 and 18 was associated with a statistically significant decreased BC risk compared to small body size (pooled OR (95% CI): comparing large to small, 0.78 (0.70-0.86), P trend <0.001 and 0.72 (0.64-0.80), P trend <0.001, respectively). The majority of the women (~85%) did not change body size categories between age 7 and 18 . Women who remained medium or large between ages 7 and 18 had significantly decreased BC risk compared to those who remained small. A reduction in body size between ages 7 and 18 was also found to be inversely associated with BC risk (0.90 (0.81-1.00)). No significant association was found between body size at age 7 and tumor characteristics. Body size at age 18 was found to be inversely associated with tumor size (P trend = 0.006), but not estrogen receptor status and lymph node involvement. For all analyses, the overall inferences did not change appreciably after further adjustment for adult body mass index. Our data provide further support for a strong and independent inverse relationship between early life body size and BC risk. The association between body size at age 18 and tumor size could be mediated by mammographic density.
Gentle, Samuel J; Travers, Colm P; Carlo, Waldemar A
2018-04-01
Caffeine use in preterm infants has endured several paradigms: from standard of care to possible neurotoxin to one of the few medications for which there is evidence of bronchopulmonary dysplasia (BPD) risk reduction. The purpose of the review is to analyze this dynamic trajectory and discuss controversies that still remain after decades of caffeine use. Following concerns for caffeine safety in preterm infants, a large randomized controlled trial demonstrated a reduction in BPD and treatment for patent ductus arteriosus. The lower rate of death or neurodevelopmental impairment noted at 18-21 months was not statistically different at later timepoints; however, infants in the caffeine group had lower rates of motor impairment at 11-year follow-up. The time of caffeine therapy initiation is now substantially earlier, and doses used are sometimes higher that previously used, but there are limited data to support these practices. Caffeine therapy for apnea of prematurity (AOP) remains one of the pillars of neonatal care, although more evidence to support dosing and timing of initiation and discontinuation are needed.
Mutz, M; Boudreaux, B; Kearney, M; Stroda, K; Gaunt, S; Shiomitsu, K
2015-12-01
Canine multi-centric B-cell lymphoma shares similarities with diffuse large B-cell (Non-Hodgkin's) lymphoma (NHL) in people. In people with NHL, lymphopenia at diagnosis and first relapse and neutrophil/lymphocyte ratio (N:L) > 3.5 are negative prognostic factors for survival. The objective of this study was to determine if lymphocyte concentration at diagnosis and first relapse and N:L were prognostic for survival in dogs with newly diagnosed multi-centric lymphoma. Medical records of 77 dogs with multi-centric lymphoma treated with a CHOP-based chemotherapy protocol were retrospectively evaluated. Absolute lymphocyte concentration and N:L ratio at presentation of dogs pre-treated with steroids was not significantly different from dogs who had not received steroids. On multivariate analysis, only immunophenotype remained significant for progression-free survival (PFS), whereas no variables remained significant for ST. A prospective study of these haematologic variables is warranted to assess their true significance. © 2013 John Wiley & Sons Ltd.
Whooping cough in 2014 and beyond: an update and review.
Hartzell, Joshua D; Blaylock, Jason M
2014-07-01
Pertussis, or whooping cough, has had a dramatic resurgence in the past several years and is the most common vaccine-preventable disease in the world. The year 2012 marked the most cases in the United States in > 50 years. Large outbreaks have occurred in multiple states, and infant deaths have drawn the attention of not only health-care providers but also the media. Although the disease is theoretically preventable by vaccination, it remains a challenge to control. New vaccination strategies have been implemented across different age groups and populations of patients, but vaccine coverage remains dismally low. Acellular vaccines, although safe, do not afford the same long-lasting immunity as the previously used whole-cell vaccine. Ultimately, improvements in the development of vaccines and in vaccination coverage will be essential to decrease the burden of pertussis on society. This article provides a review of pertussis infection and discusses advances related to the epidemiology, diagnosis, treatment, and prevention of infection, as well as continued areas of uncertainty.
Salemis, Nikolaos S; Gourgiotis, Stavros; Tsiambas, Evangelos; Karagkiouzis, Grigorios; Nakos, Georgios; Karathanasis, Vasilios
2009-01-01
Diffuse large B cell lymphoma is the most commonly diagnosed non-Hodgkin's lymphoma, whereas lymphoma is the most common cause of mesenteric masses. We herein present a very rare case of a young male patient with a giant diffuse large B cell lymphoma of the mesentery that was incidentally diagnosed during his admission for a road traffic accident. At laparotomy, a huge tumor measuring 18 x 14 x 10 cm was found originating from the jejunal mesentery. Despite the giant size of the tumor, the patient was completely asymptomatic. After complete surgical recection with clear margins, he recieved six cycles of CHOP chemotherapy in the pre-rituximab era. He remained disease-free 2 years after surgery, but unfortunately, he relapsed with disseminated disease and died 6 months later. Mesenteric lymphomas may remain asymptomatic until they reach a large size. The presence of a bulky mesenteric mass is a poor prognostic indicator. Although chemotherapy is the treatment of choice for diffuse large B cell lymphoma, in some cases radical surgery has a role in establishing a definitive diagnosis.
Health conditions and health-policy innovations in Brazil: the way forward.
Victora, Cesar G; Barreto, Mauricio L; do Carmo Leal, Maria; Monteiro, Carlos A; Schmidt, Maria Ines; Paim, Jairnilson; Bastos, Francisco I; Almeida, Celia; Bahia, Ligia; Travassos, Claudia; Reichenheim, Michael; Barros, Fernando C
2011-06-11
Brazil is a large complex country that is undergoing rapid economic, social, and environmental change. In this Series of six articles, we have reported important improvements in health status and life expectancy, which can be ascribed largely to progress in social determinants of health and to implementation of a comprehensive national health system with strong social participation. Many challenges remain, however. Socioeconomic and regional disparities are still unacceptably large, reflecting the fact that much progress is still needed to improve basic living conditions for a large proportion of the population. New health problems arise as a result of urbanisation and social and environmental change, and some old health issues remain unabated. Administration of a complex, decentralised public-health system, in which a large share of services is contracted out to the private sector, together with many private insurance providers, inevitably causes conflict and contradiction. The challenge is ultimately political, and we conclude with a call for action that requires continuous engagement by Brazilian society as a whole in securing the right to health for all Brazilian people. Copyright © 2011 Elsevier Ltd. All rights reserved.
Haffenden, Angela M; Goodale, Melvyn A
2002-12-01
Previous findings have suggested that visuomotor programming can make use of learned size information in experimental paradigms where movement kinematics are quite consistent from trial to trial. The present experiment was designed to test whether or not this conclusion could be generalized to a different manipulation of kinematic variability. As in previous work, an association was established between the size and colour of square blocks (e.g. red = large; yellow = small, or vice versa). Associating size and colour in this fashion has been shown to reliably alter the perceived size of two test blocks halfway in size between the large and small blocks: estimations of the test block matched in colour to the group of large blocks are smaller than estimations of the test block matched to the group of small blocks. Subjects grasped the blocks, and on other trials estimated the size of the blocks. These changes in perceived block size were incorporated into grip scaling only when movement kinematics were highly consistent from trial to trial; that is, when the blocks were presented in the same location on each trial. When the blocks were presented in different locations grip scaling remained true to the metrics of the test blocks despite the changes in perceptual estimates of block size. These results support previous findings suggesting that kinematic consistency facilitates the incorporation of learned perceptual information into grip scaling.
Effects of an increase in population of sika deer on beetle communities in deciduous forests.
Iida, Taichi; Soga, Masashi; Koike, Shinsuke
2016-01-01
The overabundance of large herbivores is now recognized as a serious ecological problem. However, the resulting ecological consequences remain poorly understood. The ecological effects of an increase in sika deer, Cervus nippon Temminck (Cervidae), on three insect groups of beetles was investigated: ground beetles (Carabidae), carrion beetles (Silphidae), and dung beetles (Scarabaeidae and Geotrupidae) on Nakanoshima Island, Hokkaido, northern Japan. We collected beetles on Nakanoshima Island (experimental site) and lakeshore areas (control site) and compared the species richness, abundance, diversity index, and community composition of beetles between the sites. Results showed that although both species diversity and abundance of carabid beetles were significantly higher at the lakeshore site, those of dung and carrion beetles were higher at the island site. It was additionally observed that abundance of larger carabid beetles was higher at the lakeshore site, whereas that of small-sized carabid beetles did not differ between the lakeshore and island sites. For dung beetles, abundance of smaller species was higher at the island site, whereas that of large species did not differ between the lakeshore and island sites. Abundance of two body sizes (small and large) of carrion beetles were both higher at the island site. Overall, the findings of this study demonstrated that an increase in deer population altered the insect assemblages at an island scale, suggesting further changes in ecosystem functions and services in this region.
Luncz, Lydia V; Boesch, Christophe
2015-01-01
Chimpanzees show cultural differences among populations across Africa but also between neighboring communities. The extent of these differences among neighbors, however, remains largely unknown. Comparing three neighboring chimpanzee community in the Taï National Park, Côte d'Ivoire, we found 27 putative cultural traits, including tool use, foraging, social interaction, communication and hunting behavior, exceeding by far previously known diversity. As foraging behavior is predominantly influenced by the environment, we further compared in detail ecological circumstances underlying insectivore feeding behavior to analyze whether foraging differences on Dorylus ants and Thoracotermes termites seen between neighboring chimpanzee communities were caused by environmental factors. Differences in the prey characteristics of Dorylus ants (aggression level, running speed, and nest structure) that could influence the behavior of chimpanzees were excluded, suggesting that the observed group-specific variation is not ecologically driven. Only one community preyed on Thoracotermes termites despite a similar abundance of termite mounds in all three territories, supporting the idea that this difference is also not shaped by the environment. Therefore, our study suggests that transmission of cultural knowledge plays a role in determining insectivory prey behavior. This behavioral plasticity, independent of ecological conditions, can lead to large numbers of cultural diversification between neighboring chimpanzee communities. These findings not only deepen our understanding of the cultural abilities of chimpanzees in the wild but also open up possible future comparisons of the origin of cultural diversification among humans and chimpanzees. © 2014 Wiley Periodicals, Inc.
NASA Astrophysics Data System (ADS)
Yue, Y.; Tong, X.; Wang, K.; Fensholt, R.; Brandt, M.
2017-12-01
With the aim to combat desertification and improve the ecological environment, mega-engineering afforestation projects have been launched in the karst regions of southwest China around the turn of the new millennium. A positive impact of these projects on vegetation cover has been shown, however, it remains unclear if conservation efforts have been able to effectively restore ecosystem properties and reduce the sensitivity of the karst ecosystem to climate variations at large scales. Here we use passive microwave and optical satellite time series data combined with the ecosystem model LPJ-GUESS and show widespread increase in vegetation cover with a clear demarcation at the Chinese national border contrasting the conditions of neighboring countries. We apply a breakpoint detection to identify permanent changes in vegetation time series and assess the vegetation's sensitivity against climate before and after the breakpoints. A majority (74%) of the breakpoints were detected between 2001 and 2004 and are remarkably in line with the implementation and spatial extent of the Grain to Green project. We stratify the counties of the study area into four groups according to the extent of Grain to Green conservation areas and find distinct differences between the groups. Vegetation trends are similar prior to afforestation activities (1982-2000), but clearly diverge at a later stage, following the spatial extent of conservation areas. Moreover, vegetation cover dynamics were increasingly decoupled from climatic influence in areas of high conservation efforts. Whereas both vegetation resilience and resistance were considerably improved in areas with large conservation efforts thereby showing an increase in ecosystem stability, ongoing degradation and an amplified sensitivity to climate variability was found in areas with limited project implementation. Our study concludes that large scale conservation projects can regionally contribute to a greening Earth and are able to mitigate desertification by increasing the vegetation cover and reducing the ecosystem sensitivity to climate change, however, degradation remains a serious issue in the karst ecosystem of southwest China.
Migration patterns of post-spawning Pacific herring in a subarctic sound
NASA Astrophysics Data System (ADS)
Bishop, Mary Anne; Eiler, John H.
2018-01-01
Understanding the distribution of Pacific herring (Clupea pallasii) can be challenging because spawning, feeding and overwintering may take place in different areas separated by 1000s of kilometers. Along the northern Gulf of Alaska, Pacific herring movements after spring spawning are largely unknown. During the fall and spring, herring have been seen moving from the Gulf of Alaska into Prince William Sound, a large embayment, suggesting that fish spawning in the Sound migrate out into the Gulf of Alaska. We acoustic-tagged 69 adult herring on spawning grounds in Prince William Sound during April 2013 to determine seasonal migratory patterns. We monitored departures from the spawning grounds as well as herring arrivals and movements between the major entrances connecting Prince William Sound and the Gulf of Alaska. Departures of herring from the spawning grounds coincided with cessation of major spawning events in the immediate area. After spawning, 43 of 69 tagged herring (62%) moved to the entrances of Prince William Sound over a span of 104 d, although most fish arrived within 10 d of their departure from the spawning grounds. A large proportion remained in these areas until mid-June, most likely foraging on the seasonal bloom of large, Neocalanus copepods. Pulses of tagged herring detected during September and October at Montague Strait suggest that some herring returned from the Gulf of Alaska. Intermittent detections at Montague Strait and the Port Bainbridge passages from September through early January (when the transmitters expired) indicate that herring schools are highly mobile and are overwintering in this area. The pattern of detections at the entrances to Prince William Sound suggest that some herring remain in the Gulf of Alaska until late winter. The results of this study confirm the connectivity between local herring stocks in Prince William Sound and the Gulf of Alaska.
Enhanced periodontal regeneration using collagen, stem cells or growth factors.
Basan, Tanja; Welly, Daniel; Kriebel, Katja; Scholz, Malte; Brosemann, Anne; Liese, Jan; Vollmar, Brigitte; Frerich, Bernhard; Lang, Hermann
2017-01-01
The regeneration of periodontal tissues still remains a challenge in periodontology. The aim of the present study was to examine the regenerative potential of a) different collagen support versus blank, b) different collagen support +/- a growth factor cocktail (GF) and c) a collagen powder versus collagen powder + periodontal ligament stem cells (PDLSCs) comparatively in a large animal model. The stem cells (SC) were isolated from extracted teeth of 15 adult miniature pigs. A total of 60 class II furcation defects were treated with the materials named above. Concluding, a histological evaluation followed. A significant increase in regeneration was observed in all treatment groups. The new attachment formation reached a maximum of 77 percent. In the control group a new attachment formation of 13 percent was observed. The study shows that all implanted materials improved periodontal regeneration, though there were no significant differences between the experimental groups. Within the limitations of this study, it can be assumed that the lack of significant differences is due to the complexity of the clinical setting.
Hepp, Christof; Maier, Berenike
2017-10-01
Secretion systems enable bacteria to import and secrete large macromolecules including DNA and proteins. While most components of these systems have been identified, the molecular mechanisms of macromolecular transport remain poorly understood. Recent findings suggest that various bacterial secretion systems make use of the translocation ratchet mechanism for transporting polymers across the cell envelope. Translocation ratchets are powered by chemical potential differences generated by concentration gradients of ions or molecules that are specific to the respective secretion systems. Bacteria employ these potential differences for biasing Brownian motion of the macromolecules within the conduits of the secretion systems. Candidates for this mechanism include DNA import by the type II secretion/type IV pilus system, DNA export by the type IV secretion system, and protein export by the type I secretion system. Here, we propose that these three secretion systems employ different molecular implementations of the translocation ratchet mechanism. © 2017 The Authors. BioEssays Published by WILEY Periodicals, Inc.
Sheehan, Michael J; Botero, Carlos A; Hendry, Tory A; Sedio, Brian E; Jandt, Jennifer M; Weiner, Susan; Toth, Amy L; Tibbetts, Elizabeth A
2015-10-01
Ecological constraints on independent breeding are recognised as major drivers of cooperative breeding across diverse lineages. How the prevalence and degree of cooperative breeding relates to ecological variation remains unresolved. Using a large data set of cooperative nesting in Polistes wasps we demonstrate that different aspects of cooperative breeding are likely to be driven by different aspects of climate. Whether or not a species forms cooperative groups is associated with greater short-term temperature fluctuations. In contrast, the number of cooperative foundresses increases in more benign environments with warmer, wetter conditions. The same data set reveals that intraspecific responses to climate variation do not mirror genus-wide trends and instead are highly heterogeneous among species. Collectively these data suggest that the ecological drivers that lead to the origin or loss of cooperation are different from those that influence the extent of its expression within populations. © 2015 John Wiley & Sons Ltd/CNRS.
Distinct epigenomic landscapes of pluripotent and lineage-committed human cells.
Hawkins, R David; Hon, Gary C; Lee, Leonard K; Ngo, Queminh; Lister, Ryan; Pelizzola, Mattia; Edsall, Lee E; Kuan, Samantha; Luu, Ying; Klugman, Sarit; Antosiewicz-Bourget, Jessica; Ye, Zhen; Espinoza, Celso; Agarwahl, Saurabh; Shen, Li; Ruotti, Victor; Wang, Wei; Stewart, Ron; Thomson, James A; Ecker, Joseph R; Ren, Bing
2010-05-07
Human embryonic stem cells (hESCs) share an identical genome with lineage-committed cells, yet possess the remarkable properties of self-renewal and pluripotency. The diverse cellular properties in different cells have been attributed to their distinct epigenomes, but how much epigenomes differ remains unclear. Here, we report that epigenomic landscapes in hESCs and lineage-committed cells are drastically different. By comparing the chromatin-modification profiles and DNA methylomes in hESCs and primary fibroblasts, we find that nearly one-third of the genome differs in chromatin structure. Most changes arise from dramatic redistributions of repressive H3K9me3 and H3K27me3 marks, which form blocks that significantly expand in fibroblasts. A large number of potential regulatory sequences also exhibit a high degree of dynamics in chromatin modifications and DNA methylation. Additionally, we observe novel, context-dependent relationships between DNA methylation and chromatin modifications. Our results provide new insights into epigenetic mechanisms underlying properties of pluripotency and cell fate commitment.
Beltrán-Sánchez, Hiram; Andrade, Flávia Cristina Drumond
2013-08-01
To estimate transition probabilities between disability states, total life expectancy, and the latter's decomposition into years spent disabled and disability-free by age, sex, and education among older adults in São Paulo, Brazil, and urban areas in Mexico. Applied a micro-simulation method (Interpolative Markov Chains) using longitudinal data. We found large between-country educational differences in incidence of and recovery from disability with higher rates in Mexico than in São Paulo, but no differences in mortality. Older adults in Mexico spent longer time being disability-free than in São Paulo for both levels of education. Males and females in São Paulo spent a larger fraction of their remaining life disabled at every age than their counterparts in urban areas in Mexico. There were educational differences in the prevalence of disability in São Paulo and urban areas in Mexico, and significant educational differences in disability incidence and recovery across sites.
Self-forces on static bodies in arbitrary dimensions
NASA Astrophysics Data System (ADS)
Taylor, Peter
2016-03-01
I will present exact expressions for the scalar and electromagnetic self-forces and self-torques acting on arbitrary static extended bodies in arbitrary static spacetimes with any number of dimensions. Non-perturbatively, these results are identical in all dimensions. Meaningful point particle limits are quite different, however. I will discuss how such limits are defined and evaluated, resulting in simple ``regularization algorithms'' which can be used in concrete calculations. In them, self-interaction is shown to be progressively less important in higher numbers of dimensions, generically competing in magnitude with increasingly high-order extended-body effects. Conversely, self-interaction effects can be relatively large in 1 + 1 and 2 + 1 dimensions. It will further be shown that there is considerable freedom to use different ``effective fields'' in the laws of motion. Different choices give rise to different inertias, gravitational forces, and electromagnetic or scalar self-forces. However, the particular combinations of these quantities which are observable remain invariant under all possible field redefinitions.
Structure and composition of altered riparian forests in an agricultural Amazonian landscape.
Nagy, R Chelsea; Porder, Stephen; Neill, Christopher; Brando, Paulo; Quintino, Raimundo Mota; do Nascimento, Sebastiâo Aviz
2015-09-01
Deforestation and fragmentation influence the microclimate, vegetation structure, and composition of remaining patches of tropical forest. In the southern Amazon, at the frontier of cropland expansion, forests are converted and fragmented in a pattern that leaves standing riparian forests whose dimensions are mandated by the Brazilian National Forest Code. These altered riparian forests share many characteristics of well-studied upland forest fragments, but differ because they remain connected to larger areas of forest downstream, and because they may experience wetter soil conditions because reduction of forest cover in the surrounding watershed raises groundwater levels and increases stream runoff. We compared forest regeneration, structure, composition, and diversity in four areas of intact riparian forest and four areas each of narrow, medium, and wide altered riparian forests that have been surrounded by agriculture since the early 1980s. We found that seedling abundance was reduced by as much as 64% and sapling abundance was reduced by as much as 67% in altered compared to intact riparian forests. The most pronounced differences between altered and intact forest occurred near forest edges and within the narrowest sections of altered riparian forests. Woody plant species composition differed and diversity was reduced in altered forests compared to intact riparian forests. However, despite being fragmented for several decades, large woody plant biomass and carbon storage, the number of live or dead large woody plants, mortality rates, and the size distribution of woody plants did not differ significantly between altered and intact riparian forests. Thus, even in these relatively narrow forests with high edge: area ratios, we saw no evidence of the increases in mortality and declines in biomass that have been found in other tropical forest fragment studies. However, because of the changes in both species community and reduced regeneration, it is unclear how long this relative lack of change will be sustained. Additionally, Brazil recently passed a law in their National Forest Code allowing narrower riparian buffers than those studied here in restored areas, which could affect their long-term sustainability.
Parkin Kullmann, Jane Alana
2017-01-01
Objectives The ratio of the length of the index finger (2D) to the ring finger (4D) (2D:4D) has been reported to be lower (ie, 2D<4D) in people with amyotrophic lateral sclerosis (ALS) than non-ALS controls. This has led to suggestions that exposure to increased prenatal testosterone, which also lowers this ratio, could be a risk factor for ALS. In an attempt to test this hypothesis, we examined 2D:4Ds from large numbers of patients with ALS and controls. Setting An online multilingual questionnaire enabling respondents to measure their own index and ring finger lengths. Participants Of the initial 949 respondents, 572 remained for analysis after elimination for inability to straighten fingers, not answering the question, statistical outliers and aged <40 years. Respondents remaining for analysis were 202 patients with ALS (125 males, 77 females) and 370 non-ALS controls (112 males, 258 females). Results Unpaired t-tests with 95% CIs were used to assess differences in mean 2D:4Ds. Males had significantly lower mean 2D:4Ds than females, in both ALS and control groups, for both left and right hands. No significant differences were found in 2D:4Ds between ALS and control groups, in either males or females, for either left or right hands. Receiver operating characteristic curves showed no power for 2D:4Ds to predict ALS status in either males or females. Conclusions 2D:4Ds did not differ between patients with ALS and controls in this study. This was despite the dataset being large enough to confirm the established finding of lower 2D:4Ds in males compared with females. These findings do not support the hypothesis that exposure to increased prenatal testosterone is a risk factor for ALS. A putative lower 2D:4D has been proposed to explain the link between ALS and exercise, but our results indicate that other exercise-related factors are more likely to explain this association. PMID:28784596
NASA Astrophysics Data System (ADS)
Bermúdez de Castro, José María; Martinón-Torres, María; Blasco, Ruth; Rosell, Jordi; Carbonell, Eudald
2013-09-01
The nature, timing, pattern, favourable circumstances and impediments of the human occupation of the European continent during the Early Pleistocene are hot topics in Quaternary studies. In particular, the problem of the (dis) continuity of the settlement of Europe in this period is an important matter of discussion, which has been approached in the last decade from different points of view. The Gran Dolina (TD) and Sima del Elefante (TE) cave sites in the Sierra de Atapuerca, (Spain) include large and quasi-continuous stratigraphic sequences that stretch back from at least 1.2 million years ago (Ma) to the Matuyama/Brunhes boundary. The archaeological and paleontological record from these sites can help to test different hypotheses about the character of the human settlement in this region and period. Furthermore, the TD6 level has yielded a large collection of human fossil remains attributed to Homo antecessor. According to different geochronological methods, as well as to paleomagnetic and biostratigraphical analyses, these hominins belong to an age range of 0.96-0.80 Ma. Unfortunately, the finding in 2007 of some human fossil remains in the TE9 level, dated to about 1.22 Ma, was not enough to conclude whether H. antecessor had deep roots in the European Early Pleistocene. A set of derived features of H. antecessor shared with both the Neanderthal lineage and modern humans suggests that this species is related, and not far, from the most recent common ancestor (MRCA) of Homo neanderthalensis and Homo sapiens. If we assume that there was a lineal biological relationship between the TE9 and TD6 hominins, we should reconsider many of the conclusions achieved in previous paleontological and genetic studies. In addition, we would be obliged to build a highly complicated paleogeographical scenario for the origin of the MRCA. Although continuity in the settlement of Europe during the entire late Early Pleistocene is not discarded (e.g. in refuge areas), it seems that this Western extreme of Eurasia, and the Iberian Peninsula in particular, was occupied by at least two different hominin populations.
Biochemical properties of the nerve growth factor-inducible large external (NILE) glycoprotein.
Salton, S R; Shelanski, M L; Greene, L A
1983-12-01
In the presence of nerve growth factor (NGF), PC12 pheochromocytoma cells undergo neuronal differentiation with a concomitant 3- to 5-fold increase in the specific level of an Mr = 230,000 cell surface component named the NGF-inducible large external, or NILE, glycoprotein. Antisera raised against NILE glycoprotein (NILE GP) purified from PC12 cells have been found to recognize most, if not all, neurons derived from the peripheral and central nervous systems. In the current studies several of the biochemical properties of NILE GP were investigated. NILE GP was found to be phosphorylated in NGF-treated and -untreated PC12 cells and in cultured rat sympathetic neurons. The phosphate moiety of NILE GP is almost completely alkali labile, suggesting that phosphoserine groups predominate. Immunoprecipitation experiments revealed that incorporation of [32P]phosphate into NILE GP relative to total PC12 cell phosphoprotein was not significantly altered at 12 and 24 hr of NGF treatment but was enhanced 3-fold after 7 days and up to 5-fold after 2 to 3 weeks of NGF exposure. These changes in phosphorylated NILE GP paralleled, and therefore appeared to be mainly a consequence of, the NGF-induced increase in total cellular levels of NILE GP. By two-dimensional gel analysis, anti-NILE GP selectively immunoprecipitated two NGF-inducible spots (apparent Mr = 230,000; pI = 6.4 to 6.6) from PC12 cells labeled with either [3H] fucose, [35S]methionine, or [32P]phosphate. Anti-NILE GP immunoprecipitated a single band (apparent Mr = 205,000) from extracts of rat brain labeled with [3H] glucosamine. This confirms the previously established apparent molecular weight difference between central and peripheral NILE GP cross-reactive material. When PC12 cells, cerebellar cultures, and cultured cerebral cortex were treated with tunicamycin and labeled with [35S]methionine, nonglycosylated bands each with Mr = 160,000 were immunoprecipitated, implying that the differences in the mobilities on sodium dodecyl sulfate gels of cross-reactive NILE GP from different tissues is due to variation in glycosylation rather than to large differences in apoprotein structure. Prolonged treatment of PC12 cells with trypsin produced an immunoreactive fragment of NILE GP of apparent Mr = 28,000 that was phosphorylated but not glycosylated, and that remained in the membrane. NILE GP remained predominantly membrane associated under a variety of aqueous extraction conditions, suggesting that it is an integral membrane protein.
An Impact Evaluation of the "FoodMate" Programme: Perspectives of Homeless Young People and Staff
ERIC Educational Resources Information Center
Meiklejohn, Sarah J.; Barbour, Liza; Palermo, Claire E.
2017-01-01
Objectives: Food insecurity remains an issue for vulnerable populations in developed countries. The potential dietary and food security impacts of nutrition education programmes in Australia remain largely undocumented. This study investigated the impacts of an eight-session nutrition education programme delivered within community case management…
Study Abroad and the City: Mapping Urban Identity
ERIC Educational Resources Information Center
Blair, Scott
2011-01-01
Study abroad by U.S. students, despite recent growth into non-western and rural destinations, often remains focused on cities, often very large and highly urbanized ones. While the destination cities for study abroad are located across the globe, European cities remain predominant, and thus, this article focuses on study abroad in one city. The…
Scientific Management Still Endures in Education
ERIC Educational Resources Information Center
Ireh, Maduakolam
2016-01-01
Some schools in America have changed, while others remain unchanged due largely to the accretion of small adjustments in what remains a very traditional enterprise. The problem is rooted in the propagation and adoption of scientific management by educators who applied and/or continues to apply it to education to restore order and for…
Seasonal habitat associations of the wolverine in central Idaho
Jeffrey P. Copeland; James M. Peek; Craig R. Groves; Wayne E. Melquist; Kevin S. Mckelvey; Gregory W. McDaniel; Clinton D. Long; Charles E. Harris
2007-01-01
Although understanding habitat relationships remains fundamental to guiding wildlife management, these basic prerequisites remain vague and largely unstudied for the wolverine. Currently, a study of wolverine ecology conducted in Montana, USA, in the 1970s is the sole source of information on habitat requirements of wolverines in the conterminous United States. The...
Large scale silver nanowires network fabricated by MeV hydrogen (H+) ion beam irradiation
NASA Astrophysics Data System (ADS)
Honey, S.; Naseem, S.; Ishaq, A.; Maaza, M.; Bhatti, M. T.; Wan, D.
2016-04-01
A random two-dimensional large scale nano-network of silver nanowires (Ag-NWs) is fabricated by MeV hydrogen (H+) ion beam irradiation. Ag-NWs are irradiated under H+ ion beam at different ion fluences at room temperature. The Ag-NW network is fabricated by H+ ion beam-induced welding of Ag-NWs at intersecting positions. H+ ion beam induced welding is confirmed by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Moreover, the structure of Ag NWs remains stable under H+ ion beam, and networks are optically transparent. Morphology also remains stable under H+ ion beam irradiation. No slicings or cuttings of Ag-NWs are observed under MeV H+ ion beam irradiation. The results exhibit that the formation of Ag-NW network proceeds through three steps: ion beam induced thermal spikes lead to the local heating of Ag-NWs, the formation of simple junctions on small scale, and the formation of a large scale network. This observation is useful for using Ag-NWs based devices in upper space where protons are abandoned in an energy range from MeV to GeV. This high-quality Ag-NW network can also be used as a transparent electrode for optoelectronics devices. Project supported by the National Research Foundation of South Africa (NRF), the French Centre National pour la Recherche Scientifique, iThemba-LABS, the UNESCO-UNISA Africa Chair in Nanosciences & Nanotechnology, the Third World Academy of Science (TWAS), Organization of Women in Science for the Developing World (OWSDW), the Abdus Salam ICTP via the Nanosciences African Network (NANOAFNET), and the Higher Education Commission (HEC) of Pakistan.
Takayama, Kazuo; Morisaki, Yuta; Kuno, Shuichi; Nagamoto, Yasuhito; Harada, Kazuo; Furukawa, Norihisa; Ohtaka, Manami; Nishimura, Ken; Imagawa, Kazuo; Sakurai, Fuminori; Tachibana, Masashi; Sumazaki, Ryo; Noguchi, Emiko; Nakanishi, Mahito; Hirata, Kazumasa; Kawabata, Kenji; Mizuguchi, Hiroyuki
2014-11-25
Interindividual differences in hepatic metabolism, which are mainly due to genetic polymorphism in its gene, have a large influence on individual drug efficacy and adverse reaction. Hepatocyte-like cells (HLCs) differentiated from human induced pluripotent stem (iPS) cells have the potential to predict interindividual differences in drug metabolism capacity and drug response. However, it remains uncertain whether human iPSC-derived HLCs can reproduce the interindividual difference in hepatic metabolism and drug response. We found that cytochrome P450 (CYP) metabolism capacity and drug responsiveness of the primary human hepatocytes (PHH)-iPS-HLCs were highly correlated with those of PHHs, suggesting that the PHH-iPS-HLCs retained donor-specific CYP metabolism capacity and drug responsiveness. We also demonstrated that the interindividual differences, which are due to the diversity of individual SNPs in the CYP gene, could also be reproduced in PHH-iPS-HLCs. We succeeded in establishing, to our knowledge, the first PHH-iPS-HLC panel that reflects the interindividual differences of hepatic drug-metabolizing capacity and drug responsiveness.