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Extracting Personal Behavioral Patterns from Geo-Referenced Tweets
This paper presents an exploratory study of the potential of geo-referenced Twitter data for extracting knowledge about significant personal places, behaviors and potential interests of people. The study was done analysing two monthsâ worth of tweets from residents of the greater Seattle area
Appearance concerns in later life: Do they really exist?
In Western society, where youth and beauty are given high status, older people can often feel pressured to adopt appearance-enhancing strategies, such as using anti-ageing products. Those who invest time and money into their image often do so to show they are coping well with later life and gain respect from others. Claire Hamlet examines the concept of successful ageing in relation to appearanc
On the number of solutions of a transcendental equation arising in the theory of gravitational lensing
The equation in the title describes the number of bright images of a point
source under lensing by an elliptic object with isothermal density. We prove
that this equation has at most 6 solutions. Any number of solutions from 1 to 6
can actually occur.Comment: 26 pages, 12 figure
MOLT PATTERNS AND SEXING AND AGING CRITERIA FOR TEN SPECIES OF HIGH ELEVATION LANDBIRDS FROM SOUTHEASTERN PERU
Abstract â Knowledge of molt patterns and their resulting plumages is useful for aging and sexing birds and, in monoâ chromatic species, morphometric measurements can help to discern males from females. However, these data are largely undescribed for the majority of the worldâs bird species, especially in the tropics. We sought to classify the molt strategy for 10 species of Neotropical passerines during their breeding seasons and considered whether a combination of wing chord, tail length and mass could be used to determine their sex. We used banding data from three years of markârecapture study at Wayqecha Biological Station (2900 m a.s.l.) along the east slope of the Andes in southeastern Peru to characterize molt and estimate morphological measurements. Each of the species exhibited a complete definitive prebasic molt and either a partial (nine species) or partialâincomplete (one species) preformative molt, which we interpreted to be consistent with a complex basic molt strategy. For five of the 10 species, we found that wing, tail, and body mass measurements were useful in distinguishing between males and females. This study contributes to our understanding of tropical bird molt by providing previously undescribed aging and sexing criteria for some tropical landbirds common to high elevations of southern Peru.Resumen â Patrones de muda y criterios para categorizar sexo y edad en diez especies de aves altoandinas en el sureste de PerĂș Los patrones de muda en la mayorĂa de las aves Neotropicales son poco conocidos y en especial se desconoce si las medidas corporales pueden ser usadas para determinar el sexo en especies sin dimorfismo sexual. En este trabajo clasificamos la estrategia de muda para 10 especies de paserinos Neotropicales y tambiĂ©n exploramos si una combiâ naciĂłn de medidas de longitud del ala, longitud de la cola y masa corporal pueden ser usadas para la determinaciĂłn del sexo. Usamos datos de anillamiento de tres años de un estudio de recaptura en la EstaciĂłn BiolĂłgica Wayqecha (2900 m s.n.m.) en el flanco oriental de los Andes al sureste de PerĂș. Cada especie exhibiĂł una estrategia bĂĄsica compleja de muda con una muda prebĂĄsica definitiva compleja, y una muda preformativa parcial (nueve especies) o parcialâincompleta (uno especie). Para cinco de cada 10 especies, la combinaciĂłn de medidas de la longitud del ala, la cola, y la masa corporal sirvieron para distinguir entre machos y hembras. Este estudio contribuye a la creciente literatura sobre los patrones de muda en aves tropicales y provee herramientas para clasificar la edad y el sexo de aves con plumaje sexualmente monocromĂĄtico
Towards a standard jet definition
In a simulated measurement of the -boson mass, evaluation of Fisher's
information shows the optimal jet definition to be physically equivalent to the
algorithm while being much faster at large multiplicities.Comment: version to appear in Phys. Rev. Lett., 4 page
Readiness to change drinking behaviour among heavy-drinking university students in England
There is growing literature on possible ways of reducing alcohol consumption and alcohol-related harm among university students (Larimer and Cronce, 2002; Siegers and Carey, 2010). However, interventions with this aim might be made more effective by information on studentsâ readiness to change their drinking behaviour (Carey et al., 2007a), where an assessment of readiness to change might influence the kind of approach that is thought most likely to be successful. For example, it has been found that readiness to change moderated the effects of a brief intervention among heavy-drinking students (either brief motivational intervention or alcohol expectancy challenge) such that high readiness to change made an expectancy challenge relatively more effective in reducing drinking (Capone and Wood, 2009). This study also reported an association between higher readiness to change and greater reductions in alcohol consumption in the overall sample, thus supporting previous findings (Fromme and Corbin, 2004; Carey et al., 2007b).
Although high readiness to change may increase the chances of successful brief intervention among heavy-drinking students, it has been found that, even among individuals referred to a university-based alcohol intervention programme, there was limited acknowledgement of a drinking problem or interest in changing behaviour (Caldwell, 2002; Vik et al., 2000). Such research has been conducted mainly in the USA and, with the exception of one study (Hosier, 2001), it is unknown whether a comparable lack of concern about heavy drinking is true of students in England. Moreover, there is limited understanding of the different factors associated with, and predictive of, readiness to change in heavy-drinking students.
The aims of this paper are therefore (i) to assess levels of readiness to change among heavy-drinking students at universities in England, (ii) to identify variables predictive of readiness to change among heavy-drinking students and (iii) to generate hypotheses that could be tested in further research
Menâs Baldness Stigma and Body Dissatisfaction
Introduction: Head hair forms a central component of the sociocultural male appearance ideal (e.g.,
mesomorphic, tall, young and not bald) and carries masculine connotations and stigma. Immense pressures to conform to this male appearance ideal gives rise to body dissatisfaction. Previous assessments of body dissatisfaction are too narrow, ignoring dissatisfaction beyond mesomorphy such as baldness dissatisfaction. Our study involved two research questions: (i) Do the facial expressions assigned to images of bald and non-bald men differ? and (ii) What forms of body dissatisfaction, including baldness dissatisfaction, do men have and are these related to menâs wellbeing and muscularity behaviours?
Method: Eighty-six male participants aged 18â58 years (mean = 23.62; standard deviation = 7.80) were randomly exposed to 10 images of smiling men (half balding and half not) and were asked to rate the facial expression displayed. Participants also rated their body dissatisfaction and wellbeing. Ethics statement: Institutional ethics approval was granted.
Results: We found that participants interpreted the facial expressions of images of bald men slightly more negatively than non-bald men. Most participants reported some form of body dissatisfaction correlated with wellbeing and muscularity enhancing behaviours, albeit weakly. Participants also disclosed a range of body dissatisfaction aspects (including surrounding muscularity, body fat, teeth alignment, skin tone and facial hair amount) though generally were not impacted heavily nor highly dissatisfied.
Conclusion: These findings underscore the complex challenge in producing a complete assessment of menâs body dissatisfaction and the general resilience men experience with extant appearance pressures around their bodies and head hair
Amino Acid Deprivation Promotes Tumor Angiogenesis through the GCN2/ATF4 Pathway
AbstractAs tumors continue to grow and exceed their blood supply, nutrients become limited leading to deficiencies in amino acids (AAD), glucose (GD), and oxygen (hypoxia). These alterations result in significant changes in gene expression. While tumors have been shown to overcome the stress associated with GD or hypoxia by stimulating vascular endothelial growth factor (VEGF)-mediated angiogenesis, the role of AAD in tumor angiogenesis remains to be elucidated. We found that in human tumors, the expression of the general control non-derepressible 2 (GCN2, an AAD sensor) kinase is elevated at both protein and mRNA levels. In vitro studies revealed that VEGF expression is universally induced by AAD treatment in all five cell lines tested (five of five). This is in contrast to two other angiogenesis mediators interleukin-6 (two of five) and fibroblast growth factor 2 (two of five) that have a more restricted expression. Suppressing GCN2 expression significantly decreased AAD-induced VEGF expression. Silencing activating transcription factor 4 (ATF4), a downstream transcription factor of the GCN2 signaling pathway, is also associated with strong inhibition of AAD-induced VEGF expression. PKR-like kinase, the key player in GD-induced unfolded protein response is not involved in this process. In vivo xenograft tumor studies in nonobese diabetic/severe combined immunodeficient mice confirmed that knockdown of GCN2 in tumor cells retards tumor growth and decreases tumor blood vessel density. Our results reveal that the GCN2/ATF4 pathway promotes tumor growth and angiogenesis through AAD-mediated VEGF expression and, thus, is a potential target in cancer therapy
Rhabdomyosarcoma cells show an energy producing anabolic metabolic phenotype compared with primary myocytes
<p>Abstract</p> <p>Background</p> <p>The functional status of a cell is expressed in its metabolic activity. We have applied stable isotope tracing methods to determine the differences in metabolic pathways in proliferating Rhabdomysarcoma cells (Rh30) and human primary myocytes in culture. Uniformly <sup>13</sup>C-labeled glucose was used as a source molecule to follow the incorporation of <sup>13</sup>C into more than 40 marker metabolites using NMR and GC-MS. These include metabolites that report on the activity of glycolysis, Krebs' cycle, pentose phosphate pathway and pyrimidine biosynthesis.</p> <p>Results</p> <p>The Rh30 cells proliferated faster than the myocytes. Major differences in flux through glycolysis were evident from incorporation of label into secreted lactate, which accounts for a substantial fraction of the glucose carbon utilized by the cells. Krebs' cycle activity as determined by <sup>13</sup>C isotopomer distributions in glutamate, aspartate, malate and pyrimidine rings was considerably higher in the cancer cells than in the primary myocytes. Large differences were also evident in de novo biosynthesis of riboses in the free nucleotide pools, as well as entry of glucose carbon into the pyrimidine rings in the free nucleotide pool. Specific labeling patterns in these metabolites show the increased importance of anaplerotic reactions in the cancer cells to maintain the high demand for anabolic and energy metabolism compared with the slower growing primary myocytes. Serum-stimulated Rh30 cells showed higher degrees of labeling than serum starved cells, but they retained their characteristic anabolic metabolism profile. The myocytes showed evidence of de novo synthesis of glycogen, which was absent in the Rh30 cells.</p> <p>Conclusion</p> <p>The specific <sup>13</sup>C isotopomer patterns showed that the major difference between the transformed and the primary cells is the shift from energy and maintenance metabolism in the myocytes toward increased energy and anabolic metabolism for proliferation in the Rh30 cells. The data further show that the mitochondria remain functional in Krebs' cycle activity and respiratory electron transfer that enables continued accelerated glycolysis. This may be a common adaptive strategy in cancer cells.</p
Solute and sediment export from Amazon forest and soybean headwater streams
Author Posting. © Ecological Society of America, 2016. This article is posted here by permission of Ecological Society of America for personal use, not for redistribution. The definitive version was published in Ecological Applications 27 (2017): 193â207, doi:10.1002/eap.1428.Intensive cropland agriculture commonly increases streamwater solute concentrations and export from small watersheds. In recent decades, the lowland tropics have become the world's largest and most important region of cropland expansion. Although the effects of intensive cropland agriculture on streamwater chemistry and watershed export have been widely studied in temperate regions, their effects in tropical regions are poorly understood. We sampled seven headwater streams draining watersheds in forest (n = 3) or soybeans (n = 4) to examine the effects of soybean cropping on stream solute concentrations and watershed export in a region of rapid soybean expansion in the Brazilian state of Mato Grosso. We measured stream flows and concentrations of NO3â, PO43â, SO42â, Clâ, NH4+, Ca2+, Mg2+, Na+, K+, Al3+, Fe3+, and dissolved organic carbon (DOC) biweekly to monthly to determine solute export. We also measured stormflows and stormflow solute concentrations in a subset of watersheds (two forest, two soybean) during two/three storms, and solutes and ÎŽ18O in groundwater, rainwater, and throughfall to characterize watershed flowpaths. Concentrations of all solutes except K+ varied seasonally in streamwater, but only Fe3+ concentrations differed between land uses. The highest streamwater and rainwater solute concentrations occurred during the peak season of wildfires in Mato Grosso, suggesting that regional changes in atmospheric composition and deposition influence seasonal stream solute concentrations. Despite no concentration differences between forest and soybean land uses, annual export of NH4+, PO43â, Ca2+, Fe3+, Na+, SO42â, DOC, and TSS were significantly higher from soybean than forest watersheds (5.6-fold mean increase). This increase largely reflected a 4.3-fold increase in water export from soybean watersheds. Despite this increase, total solute export per unit watershed area (i.e., yield) remained low for all watersheds (<1 kg NO3â N·haâ1·yrâ1, <2.1 kg NH4+-N·haâ1·yrâ1, <0.2 kg PO43â-P·haâ1·yrâ1, <1.5 kg Ca2+·haâ1·yrâ1). Responses of both streamflows and solute concentrations to crop agriculture appear to be controlled by high soil hydraulic conductivity, groundwater-dominated hydrologic flowpaths on deep soils, and the absence of nitrogen fertilization. To date, these factors have buffered streams from the large increases in solute concentrations that often accompany intensive croplands in other locations.NSF Grant Numbers: DEB-0640661, DEB-0949370;
Fundação de Amparo å Pesquisa do Estado de São Paulo Grant Number: FAPESP 03/13172-2;
Watson Graduate Student Fellowship;
Center for Latin American and Caribbean Studies at Brown Universit
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