99 research outputs found
Ultraviolet (UV) B effects on growth and yield of three contrasting sweet potato cultivars
Ground-level UV-B will stay at a high level in the next several decades and influence sweet potato growth and yield because of the remaining chlorofluorocarbons in the atmosphere. The study explored three UV-B (none, ambient, and elevated/projected) levels on three contrasting sweet potato cultivars (Beauregard, Hatteras, and Louisiana 1188) using sunlit plant growth chambers at Mississippi State University. The results showed that UV-B influenced three cultivars differently. Growth, photosynthetic rate, epidermal and leaf structure of Beauregard were negatively influenced under ambient and elevated UV-B. On the contrary, Hatteras was positively influenced, and Louisiana 1188 was influenced by elevated UV-B positively on leaf thickness and waxes content, but negatively on the vine length, dry mass, and leaf area. In summary, Beauregard, Louisiana 1188, and Hatteras were UV-B sensitive, moderately sensitive, and tolerant, respectively. Developing UV-B tolerant cultivars will benefit under both current and projected UV-B exposures
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Factors Influencing Sleep Difficulty and Sleep Quantity in the Citizen Pscientist Psoriatic Cohort.
IntroductionSleep is essential for overall health and well-being, yet more than one-third of adults report inadequate sleep. The prevalence is higher among people with psoriasis, with up to 85.4% of the psoriatic population reporting sleep disruption. Poor sleep among psoriasis patients is particularly concerning because psoriasis is independently associated with many of the same comorbidities as sleep dysfunction, including cardiovascular disease, obesity, and depression. Given the high prevalence and serious consequences of disordered sleep in psoriasis, it is vital to understand the nature of sleep disturbance in this population. This study was designed to help meet this need by using survey data from Citizen Pscientist, an online patient portal developed by the National Psoriasis Foundation.MethodsOur analysis included 3118 participants who identified as having a diagnosis by a physician of psoriasis alone or psoriasis with psoriatic arthritis. Demographic information, psoriasis severity and duration, sleep apnea status, smoking and alcohol consumption, itch timing, and sleep characteristics were included. Two separate multivariate logistic regression models in STATA were used to determine whether the presence of psoriatic arthritis, age, gender, body mass index, comorbid sleep apnea, psoriasis severity, timing of worst itch, smoking status, or high-risk alcohol consumption were associated with sleep difficulty or low sleep quantity, defined by the American Academy of Sleep Medicine as less than 7Β h of sleep per night on average.ResultsResults from the multivariate logistic regressions found that sleep difficulty was associated with psoriatic arthritis (OR 2.15, 95% CI [1.79-2.58]), female gender (2.03 [1.67-2.46]), obese body mass index (BMIββ₯β30) (1.25 [1.00-1.56]), sleep apnea (1.41 [1.07-1.86]), psoriasis severity of moderate (1.59 [1.30-1.94]) or severe (2.40 [1.87-3.08]), and smoking (1.60 [1.26-2.02]). Low sleep quantity was associated with obese BMI (1.62 [1.29-2.03]), sleep apnea (1.30 [1.01-1.68]), psoriasis severity of moderate (1.41 [1.16-1.72]) or severe (1.40 [1.11-1.76]), and smoking (1.62 [1.31-2.00]). Sleep difficulty and low sleep quantity were not associated with age, alcohol consumption, or timing of worst itch.ConclusionThese results are potentially meaningful in several aspects. We identify an important distinction between sleep difficulty and sleep quantity in psoriatic disease, whereby having psoriatic arthritis and being female are each associated with sleep difficulty despite no association with low sleep quantity. Furthermore, there is conflicting evidence from prior studies as to whether psoriasis severity is associated with sleep difficulty, but this well-powered, large study revealed a strong, graded relationship between psoriasis severity and both sleep difficulty and low sleep quantity. Overall, our results show that both sleep difficulty and low sleep quantity were associated with multiple factors in this analysis of a large psoriatic cohort. These findings suggest that dermatologists may gather clinically useful information by screening psoriatic patients for trouble sleeping and low sleep quantity to identify potential comorbidities and to more effectively guide disease management
Size-dependent response of foraminiferal calcification to seawater carbonate chemistry
Michael J. Henehan acknowledges financial support from the Yale Peabody Museum.The response of the marine carbon cycle to changes in atmospheric CO2 concentrations will be determined, in part, by the relative response of calcifying and non-calcifying organisms to global change. Planktonic foraminifera are responsible for a quarter or more of global carbonate production, therefore understanding the sensitivity of calcification in these organisms to environmental change is critical. Despite this, there remains little consensus as to whether, or to what extent, chemical and physical factors affect foraminiferal calcification. To address this, we directly test the effect of multiple controls on calcification in culture experiments and core-top measurements of Globigerinoides ruber. We find that two factors, body size and the carbonate system, strongly influence calcification intensity in life, but that exposure to corrosive bottom waters can overprint this signal post mortem. Using a simple model for the addition of calcite through ontogeny, we show that variable body size between and within datasets could complicate studies that examine environmental controls on foraminiferal shell weight. In addition, we suggest that size could ultimately play a role in determining whether calcification will increase or decrease with acidification. Our models highlight that knowledge of the specific morphological and physiological mechanisms driving ontogenetic change in calcification in different species will be critical in predicting the of foraminiferal calcification to future change in atmospheric pCO2.Publisher PDFPeer reviewe
DEMONSTRATION OF THE DOE INTERIM ENERGY CONSERVATION STANDARDS FOR NEW FEDERAL RESIDENTIAL BUILDINGS: EXECUTIVE SUMMARY
In accordance with federal legislation, the U.S. Department of Energy (DOE) bas conducted a project to demonstrate use of its Interim Energy Conservation Standards for New Federal Residential Buildings. The demonstration is the second step in a three-step process: development of interim standards, demonstration of the interim standards, and development of final standards. Pacific Northwest Laboratory (PNL) collected information from the demonstration project and prepared this report under a contract with DOE. The purpose of the standards is to improve the energy efficiency of federal housing and increase the use of nondepletable energy sources. In accordance with the legislation, the standards were to be performance-based rather than prescribing specific energy conservation measures. The standards use a computer software program called COSTSAFR which individualizes the standards based on climate, housing type, and fuel costs. The standards generate minimum energy-efficiency requirements by applying the life-cycle cost methodology developed for federal projects, For the demonstration, the DOE chose live federal agency housing projects: four military housing projects and one project for the Department of Health and Human Services. DOE and PNL worked with agency housing procurement officials and designers/architects to hypothetically apply the interim standards to each housing project. PNL conducted extensive interviews with the federal agencies and design contractors to determine what impacts the standards would have on the existing agency procurement process as well as on designers. Overall, PNL found that the interim standards met the basic intent of the law. Specific actions were identified, however, that DOE could take to improve the standards and encourage the agencies to implement them. Agency personnel and designers expressed similar concerns about the standards: the minimum efficiency levels established by the standards were lower than expected and the standards did not provide an easy way to incorporate new energy-efficient and renewable resource tec.:hnolog:ies like solar heating systems. Agency personnel said the standards would fit into current procurement procedures with no big changes or cost increases, Many said the standards would decrease the time and effort they now spend to establish energy-efficiency requirements and to confirm that proposed designs comply with those requirements. Agency personnel praised the software and documentation for being easy to use and providing energy-efficiency requirements in energy dollars. Housing designers agreed that the DOE standards were easy to use to determine that their designs meet energy-efficiency goals. Many felt the information provided by the standards could be useful in the design process. Based on the demonstration, PNL recommends establishing task forces that will actively involve agency personnel and others in future revisions and development of the final standards. PNL also recommends that DOE and federal agencies investigate the use of market fuel and energy prices in the standards, rather than the prices paid by the agencies, to better reflect actual costs. A number of recommendations are made for improving communications between DOE and the users of the standards and for enhancing tools to implement the standards. Several recommendations are made for increasing the number of renewable resources that are included in the standards. Finally, PNL recommends ongoing monitoring activities to continue to identify ways in which the standards can be improved
Detection of early Alzheimer's disease in MCI patients by the combination of MMSE and an episodic memory test
BACKGROUND: Mild cognitive impairment (MCI) is a heterogeneous clinical entity that comprises the prodromal phase of Alzheimer's disease (Pr-AD). New biomarkers are useful in detecting Pr-AD, but they are not universally available. We aimed to investigate baseline clinical and neuropsychological variables that might predict progression from MCI to AD dementia.
METHODS: All patients underwent a complete clinical and neuropsychological evaluation at baseline and every 6 months during a two-year follow-up period, with 54 out of 109 MCI patients progressing to dementia (50 of them progressed to AD dementia), and 55 remaining as stable MCI (S-MCI).
RESULTS: A combination of MMSE and California Verbal Learning Test Long Delayed Total Recall (CVLT-LDTR) constituted the best predictive model: subjects scoring above 26/30 on MMSE and 4/16 on CVLT-LDTR had a negative predictive value of 93.93% at 2 years, whereas those subjects scoring below both of these cut-off scores had a positive predictive value of 80.95%.
CONCLUSIONS: Pr-AD might be distinguished from S-MCI at baseline using the combination of MMSE and CVLT-LDTR. These two neuropsychological predictors are relatively brief and may be readily completed in non-specialist clinical settings
Alcohol, tobacco and illicit drug use amongst same-sex attracted women: results from the Western Australian Lesbian and Bisexual Women's Health and Well-Being Survey
Background: The prevalence of alcohol, tobacco and illicit drug use has been reported to be higheramongst lesbian and bisexual women (LBW) than their heterosexual counterparts. However, few studieshave been conducted with this population in Australia and rates that have been reported vary considerably.Methods: A self-completed questionnaire exploring a range of health issues was administered to 917women aged 15-65 years (median 34 years) living in Western Australia, who identified as lesbian orbisexual, or reported having sex with another woman. Participants were recruited from a range of settings,including Perth Pride Festival events (67.0%, n = 615), online (13.2%, n = 121), at gay bars and nightclubs(12.9%, n = 118), and through community groups (6.9%, n = 63). Results were compared against availablestate and national surveillance data.Results: LBW reported consuming alcohol more frequently and in greater quantities than women in thegeneral population. A quarter of LBW (25.7%, n = 236) exceeded national alcohol guidelines by consumingmore than four standard drinks on a single occasion, once a week or more. However, only 6.8% (n = 62)described themselves as a heavy drinker, suggesting that exceeding national alcohol guidelines may be anormalised behaviour amongst LBW. Of the 876 women who provided data on tobacco use, 28.1% (n =246) were smokers, nearly double the rate in the female population as a whole. One third of the sample(33.6%, n = 308) reported use of an illicit drug in the previous six months. The illicit drugs most commonlyreported were cannabis (26.4%, n = 242), meth/amphetamine (18.6%, n = 171), and ecstasy (17.9%, n =164). Injecting drug use was reported by 3.5% (n = 32) of participants.Conclusion: LBW appear to use alcohol, tobacco and illicit drugs at higher rates than women generally,indicating that mainstream health promotion messages are not reaching this group or are not perceivedas relevant. There is an urgent need for public health practitioners working in the area of substance useto recognise that drug consumption and use patterns of LBW are likely to be different to the widerpopulation and that special considerations and strategies are required to address the unique and complexneeds of this population
Developmental Patterns of Doublecortin Expression and White Matter Neuron Density in the Postnatal Primate Prefrontal Cortex and Schizophrenia
Postnatal neurogenesis occurs in the subventricular zone and dentate gyrus, and evidence suggests that new neurons may be present in additional regions of the mature primate brain, including the prefrontal cortex (PFC). Addition of new neurons to the PFC implies local generation of neurons or migration from areas such as the subventricular zone. We examined the putative contribution of new, migrating neurons to postnatal cortical development by determining the density of neurons in white matter subjacent to the cortex and measuring expression of doublecortin (DCX), a microtubule-associated protein involved in neuronal migration, in humans and rhesus macaques. We found a striking decline in DCX expression (human and macaque) and density of white matter neurons (humans) during infancy, consistent with the arrival of new neurons in the early postnatal cortex. Considering the expansion of the brain during this time, the decline in white matter neuron density does not necessarily indicate reduced total numbers of white matter neurons in early postnatal life. Furthermore, numerous cells in the white matter and deep grey matter were positive for the migration-associated glycoprotein polysialiated-neuronal cell adhesion molecule and GAD65/67, suggesting that immature migrating neurons in the adult may be GABAergic. We also examined DCX mRNA in the PFC of adult schizophrenia patients (nβ=β37) and matched controls (nβ=β37) and did not find any difference in DCX mRNA expression. However, we report a negative correlation between DCX mRNA expression and white matter neuron density in adult schizophrenia patients, in contrast to a positive correlation in human development where DCX mRNA and white matter neuron density are higher earlier in life. Accumulation of neurons in the white matter in schizophrenia would be congruent with a negative correlation between DCX mRNA and white matter neuron density and support the hypothesis of a migration deficit in schizophrenia
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