141 research outputs found
Scaling from single-point sap velocity measurements to stand transpiration in a multispecies deciduous forest: Uncertainty sources, stand structure effect, and future scenarios
9 páginas.-- 5 figuras.-- 2 tablas.-- 58 referencias[EN] A major challenge in studies estimating stand water use in mixed-species forests is how to effectively scale data from individual trees to the stand. This is the case for forest ecosystems in the northeastern USA where differences in water use among species and across different size classes have not been extensively studied, despite their relevance for a wide range of ecosystem services. Our objectives were to assess the importance of different sources of variability on transpiration upscaling and explore the potential impacts of future shifts in species composition on the forest water budget. We measured sap velocity in five tree species (Fagus grandifolia Ehrh., Acer rubrum L., Acer saccharum Marsh., Betula alleghaniensis Britton, and Betula papyrifera Marsh.) in
a mature stand and a young stand in New Hampshire, USA. Our results showed that the greatest potential source of error was radial variability and that tree size was more important than species in determining sap velocity. Total sapwood area was demonstrated to exert a strong controlling influence on transpiration, varying depending on tree size and species. We conclude that the effect of potential species shifts on transpiration will depend on the sap velocity, determined not only by radial variation and tree size, but also by the sapwood area distribution in the stand.[FR] Les études dont le but est d'estimer l'utilisation de l'eau a` l'échelle du peuplement dans les forêts mélangées font face a` un défi majeur : comment passer efficacement de l'échelle des arbres individuels a` l'échelle du peuplement. C'est le cas pour les écosystèmes forestiers dans le nord-est des États-Unis où les différences dans l'utilisation de l'eau entre les espèces et parmi les différentes catégories de taille n'ont pas fait l'objet d'études approfondies malgré leur pertinence pour une vaste gamme de services de l'écosystème. Nos objectifs consistaient a` évaluer l'importance des différentes sources de variation sur l'extrapolation de la transpiration et a` explorer les impacts potentiels des changements futurs dans la composition en espèces sur le bilan hydrique de la forêt. Nous avons mesuré la vitesse de la sève chez cinq espèces d'arbre (Fagus grandifolia Ehrh., Acer rubrum L., Acer saccharum Marsh., Betula alleghaniensis Britton et Betula papyrifera Marsh.) dans un peuplement mature et dans un jeune peuplement au New Hampshire (É.-U.). Nos résultats ont montré que la plus grande source potentielle d'erreur était la variation radiale et que la vitesse de la sève était davantage déterminée par la taille des arbres que par l'espèce. La surface totale de bois d'aubier avait un effet très déterminant sur la transpiration qui variait selon la taille et l'espèce d'arbre. Nous concluons que l'effet des changements potentiels dans la composition en espèces sur la transpiration dépendra de la vitesse de la sève qui est principalement déterminée par la variation radiale et la taille des arbres mais aussi de la distribution de la surface de bois d'aubier dans le peuplement.This work was funded by the University of New Hampshire and the New Hampshire Agricultural Experiment Station. The Bartlett Experimental Forest is operated by the USDA Forest Service Northern Research Station. S. Mcgraw, P. Pellissier, C. Breton, S. Alvarado-Barrientos, R. Snyder, and Z. Aldag assisted in the field and in the lab. The 2011 stand inventory was led by S. Goswami. Tree heights were measured and compiled by C. Blodgett, T. Fahey, and L. Liu. A. Richardson shared meteorology and solar radiation data from the Bartlett Amerflux tower. The stands used in this experiment are maintained and monitored by the MELNHE project under the direction of R. Yanai and M. Fisk, with funding from NSF grants DEB 0235650 and DEB 0949324Peer reviewe
Data_Sheet_1_Exploring the impact of childhood maltreatment and BPD on impulsivity in crimes of passion.zip
BackgroundCrimes of passion, characterized as unpremeditated impulsive aggression, have garnered increasing attention in recent years. Impulsivity, a major factor in crimes of passion, is also a common feature of various health conditions, including Borderline Personality Disorder (BPD). Childhood maltreatment is considered a significant precursor to BPD and is closely related to impulsivity. Although prior research has affirmed the relationship between impulsivity, childhood maltreatment, BPD, and criminal behavior, few studies have examined these variables’ interconnections within the context of crimes of passion. This study seeks to explore the relationship between childhood maltreatment, BPD, and impulsivity in crimes of passion, assessing the former’s impact on the latter.MethodOur research examined 133 crimes of passion offenders and 149 other offenders from the Shenzhen male prison in China. All 282 participants completed The Abbreviated Version of The Barratt Impulsiveness Scale (ABIS), The UPPS Impulsivity Scale (Urgency, Premeditation, Perseverance, Sensation Seeking), The McLean Screening Instrument for Borderline Personality Disorder (MSI-BPD), and The Childhood Trauma Questionnaire (CTQ).ResultsOur findings indicated that (1) crimes of passion offenders scored significantly higher in emotional neglect, physical neglect, and overall childhood maltreatment than did other offenders, and childhood maltreatment scores were notably higher in the high BPD trait group. (2) Crimes of passion offenders demonstrated significantly elevated impulsivity in attention and nonplanning scales compared to other offenders. Impulsivity scores across all scales were also significantly higher in the high BPD trait group. (3) Emotional neglect was found to significantly influence the urgency scale in crimes of passion offenders. An interaction effect was noted between physical abuse and high BPD traits, leading to increased impulsivity in crimes of passion offenders.ConclusionThis study underscores the predictive roles of childhood maltreatment and BPD in determining impulsivity within the context of crimes of passion.</p
Table_1_Exploring the impact of childhood maltreatment and BPD on impulsivity in crimes of passion.XLSX
BackgroundCrimes of passion, characterized as unpremeditated impulsive aggression, have garnered increasing attention in recent years. Impulsivity, a major factor in crimes of passion, is also a common feature of various health conditions, including Borderline Personality Disorder (BPD). Childhood maltreatment is considered a significant precursor to BPD and is closely related to impulsivity. Although prior research has affirmed the relationship between impulsivity, childhood maltreatment, BPD, and criminal behavior, few studies have examined these variables’ interconnections within the context of crimes of passion. This study seeks to explore the relationship between childhood maltreatment, BPD, and impulsivity in crimes of passion, assessing the former’s impact on the latter.MethodOur research examined 133 crimes of passion offenders and 149 other offenders from the Shenzhen male prison in China. All 282 participants completed The Abbreviated Version of The Barratt Impulsiveness Scale (ABIS), The UPPS Impulsivity Scale (Urgency, Premeditation, Perseverance, Sensation Seeking), The McLean Screening Instrument for Borderline Personality Disorder (MSI-BPD), and The Childhood Trauma Questionnaire (CTQ).ResultsOur findings indicated that (1) crimes of passion offenders scored significantly higher in emotional neglect, physical neglect, and overall childhood maltreatment than did other offenders, and childhood maltreatment scores were notably higher in the high BPD trait group. (2) Crimes of passion offenders demonstrated significantly elevated impulsivity in attention and nonplanning scales compared to other offenders. Impulsivity scores across all scales were also significantly higher in the high BPD trait group. (3) Emotional neglect was found to significantly influence the urgency scale in crimes of passion offenders. An interaction effect was noted between physical abuse and high BPD traits, leading to increased impulsivity in crimes of passion offenders.ConclusionThis study underscores the predictive roles of childhood maltreatment and BPD in determining impulsivity within the context of crimes of passion.</p
Association between CD14 Gene C-260T Polymorphism and Inflammatory Bowel Disease: A Meta-Analysis
<div><h3>Background</h3><p>The gene encoding CD14 has been proposed as an IBD-susceptibility gene with its polymorphism C-260T being widely evaluated, yet with conflicting results. The aim of this study was to investigate the association between this polymorphism and IBD by conducting a meta-analysis.</p> <h3>Methodology/Principal Findings</h3><p>Seventeen articles met the inclusion criteria, which included a total of 18 case-control studies, including 1900 ulcerative colitis (UC) cases, 2535 Crohn's disease (CD) cases, and 4004 controls. Data were analyzed using STATA software. Overall, association between C-260T polymorphism and increased UC risk was significant in allelic comparison (odds ratio [OR]  = 1.21, 95% confidence interval [CI]: 1.02–1.43; P = 0.027), homozygote model (OR  = 1.44, 95% CI: 1.03–2.01; P = 0.033), as well as dominant model (OR  = 1.36, 95% CI: 1.06–1.75; P = 0.016). However, there was negative association between this polymorphism and CD risk across all genetic models. Subgroup analyses by ethnicity suggested the risk-conferring profiles of -260T allele and -260 TT genotype with UC in Asians, but not in Caucasians. There was a low probability of publication bias.</p> <h3>Conclusions/Significance</h3><p>Expanding previous results of individual studies, our findings demonstrated that <em>CD14</em> gene C-260T polymorphism might be a promising candidate marker in susceptibility to UC, especially in Asians.</p> </div
The baseline characteristics of all eligible studies.
<p><i>Abbreviations</i>: HB  =  hospital-based design; PB  =  population-based design; NA  =  not available; CD  =  Crohn's disase; UC  =  ulcerative colitis.</p
Subgroup analyses of CD14 C-260T polymorphism to UC by ethnicity ( a. -260T vs. -260C allele; b. -260TT vs. -260CC; c. dominant model; d. recessive model).
<p>There was significant association among Asian populations, whereas no substantive changes was observed in Caucasians in any kind of comparisons.</p
Begg's funnel plots of publication bias test for CD14 C-260T polymorphism with UC (a. -260T vs.-260C allele; b. -260TT vs. -260CC; c. dominant model; d. recessive model).
<p>Vertical axis represents the log of OR; horizontal axis represents the SE of log(OR). Funnel plots are drawn with 95% confidence limits. OR, odds ratio; SE, standard error. The graphic symbols represents the data in the plot be sized proportional to the inverse variance.</p
Subgroup analysis of CD14 C-260T gene polymorphisms and IBD (CD and UC).
<p><i>Abbreviations</i>: OR  =  odds ratio; CI  =  confidence interval; HB  =  Hospital based; PB  =  Population based; NA  =  Not available.</p
Flow diagram of search strategy and study selection.
<p>Flow diagram of search strategy and study selection.</p
DFT and SERS Study of <sup>15</sup>N Full-Labeled Adenine Adsorption on Silver and Gold Surfaces
Adsorption
of nucleic acid bases on metal surface of nanoparticles
has received much attention recently in bio- and nanotechnology, while
it still remains a controversial problem in how adenine is adsorbed
onto the metal surface. As the nitrogen in adenine plays an important
role in the molecular recognition and interaction, the spectral feature
related to the nitrogen is the key to analysis of the adsorption configurations.
For this purpose, we employed density functional theory (DFT) calculations
at B3LYP/6-311+GÂ(d,p) level for the simulation of adsorption configurations,
and in the meantime we checked the corresponding surface enhanced
Raman spectroscopy (SERS) of <sup>15</sup>N fully labeled adenine
adsorbed on the surfaces of silver and gold nanoparticles both experimentally
and theoretically. The agreement of spectral positions, intensities,
and isotopic shifts of the SERS bands, suggests that adenine adsorbed
on either silver or gold surface takes the same adsorption configuration
in which N7H adenine interacts with Ag<sub>4</sub><sup>+</sup>/Au<sub>4</sub><sup>+</sup> cluster through both N3 and N9 sites. This study
therefore may not only provide new insight into the interaction of
adenine with noble metals but also have demonstrated the effective
approach based on the combination of DFT and SERS tools applied in
isotopic molecules to the issue of adsorption of nucleic acid bases
onto metal surfaces in general
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