Summary
The flow regime of a river is fundamental in determining its ecological characteristics. Impoundment of rivers has been documented to severely impact the natural flow regime, resulting in ...abiotic and biotic changes in downstream ecosystems. Contemporary water legislation is driving increasing concern among environmentalists and water resource managers with respect to how these impacts can be mitigated. This has stimulated research aimed at assessing the relationship between reservoir outflow modification (i.e. managed environmental flows) and downstream ecosystem responses.
We carried out a critical review and synthesis of the global literature concerning post‐impoundment reservoir outflow modification and associated downstream biotic and abiotic responses. Seventy‐six studies published between 1981 and 2012 were analysed. In contrast to previous studies of this subject, we systematically assessed the methodological quality of research to identify strengths and weaknesses of the approaches. We also undertook a novel quantification of ecosystem responses to flow modification, thus enabling identification of priorities for future research.
We identified that: (i) there was a research bias towards North American and Western European studies; (ii) the majority of studies reported changes in flow magnitude (e.g. artificial floods) and primarily focused on traditionally monitored ecological groups (e.g. fish); (iii) relationships between flow, biota (e.g. macroinvertebrates) and water quality (e.g. electrical conductivity and suspended solids concentration) were evident, demonstrating the potential for managed environmental flows to manipulate river ecosystems; (iv) site‐specific factors (e.g. location, climate) are likely to be important as some ecosystem responses were inconsistent between studies (e.g. fish movement in response to increases in flow magnitude); and (v) quality of study design, methodological and analytical techniques varied, and these factors may have contributed to the reported variability of ecosystem response.
To advance scientific understanding and guide future management of regulated flow regimes, we highlight a pressing need for: (i) diversification of study locations as well as flow modification and ecosystem response types assessed; (ii) a focus on understanding flow–ecosystem response relationships at regional scales; (iii) further quantitative studies to enable robust statistical analyses in future meta‐analyses; and (iv) robust monitoring of flow experiments and the use of contemporary statistical techniques to extract maximum knowledge from ecological response data.
The impact of human activity on the selection for antibiotic resistance in the environment is largely unknown, although considerable amounts of antibiotics are introduced through domestic wastewater ...and farm animal waste. Selection for resistance may occur by exposure to antibiotic residues or by co-selection for mobile genetic elements (MGEs) which carry genes of varying activity. Class 1 integrons are genetic elements that carry antibiotic and quaternary ammonium compound (QAC) resistance genes that confer resistance to detergents and biocides. This study aimed to investigate the prevalence and diversity of class 1 integron and integron-associated QAC resistance genes in bacteria associated with industrial waste, sewage sludge and pig slurry. We show that prevalence of class 1 integrons is higher in bacteria exposed to detergents and/or antibiotic residues, specifically in sewage sludge and pig slurry compared with agricultural soils to which these waste products are amended. We also show that QAC resistance genes are more prevalent in the presence of detergents. Studies of class 1 integron prevalence in sewage sludge amended soil showed measurable differences compared with controls. Insertion sequence elements were discovered in integrons from QAC contaminated sediment, acting as powerful promoters likely to upregulate cassette gene expression. On the basis of this data, >1 × 10(19) bacteria carrying class 1 integrons enter the United Kingdom environment by disposal of sewage sludge each year.
Background: Cervical cancer is one of the most common cancers in women and about 90% of cervical cancer can be reduced by regular screening. The Pap smear has been well in place as a primary cervical ...screening method since 1950s; however, coverage is still not optimal. This study explored the feasibility of HPV self-sampling in two under-screened population groups in Hong Kong (HK): never screened and not regularly screened females, to estimate the uptake rate and preference rate in the future. Materials and Methods: This was a cross-sectional study to explore the acceptability and feasibility of HPV self-sampling in two age groups: aged 25–35 and aged ≥45, which were reported as the highest proportion of the under-screened population in HK between 2017 and 2018. The study invited eligible women from an HPV study cohort to perform HPV self-sampling at home by themselves. The number of specimens returned from participants was recorded and used to determine the feasibility of HPV self-sampling in the community. The participants were asked to fill in the questionnaires before and after HPV self-sampling to indicate their attitudes, acceptability, and future preference for HPV self-sampling as an acceptable alternative primary cervical cancer screening method. Results: A total of 177 subjects participated in the present study and have achieved a good overall uptake rate of 73% (129/177) who returned the self-collected cervicovaginal sample for HPV testing. Among the under-screened population, there was a higher response rate in aged ≥45 than those aged 25–35. The findings also revealed that women who were under-screened, including those who have never been screened, were more likely to prefer HPV self-sampling than those who had regular screening. This study found that the acceptability of HPV self-sampling was fairly positive among the respondents. The findings also indicated that HPV self-sampling was not only beneficial to enhance their health awareness but also to promote the cervical cancer screening uptake rate, especially among the under-screened or never screened populations. Conclusions: HPV self-sampling would be a solution to overcome the perceived barriers in clinician-based screening. The findings also indicated that it could be feasible to use as an alternative primary cervical cancer screening.
The existence of cross-linguistic universals in color naming is currently contested. Early empirical studies, based principally on languages of industrialized societies, suggested that all languages ...may draw on a universally shared repertoire of color categories. Recent work, in contrast, based on languages from nonindustrialized societies, has suggested that color categories may not be universal. No comprehensive objective tests have yet been conducted to resolve this issue. We conduct such tests on color naming data from languages of both industrialized and nonindustrialized societies and show that strong universal tendencies in color naming exist across both sorts of language.
Adjuvanted herpes zoster (HZ) subunit (HZ/su) vaccine is recommended for healthy adults aged ≥50 years, yet vaccine efficacy is expected to wane over time. Age-sex specific cost-effectiveness ...analyses of HZ/su vaccine are warranted to inform decision-making on vaccine policy. We aimed to determine the optimal gender-specific age for cost-effective HZ/su vaccination in Hong Kong.
A Markov model was used to compare outcomes with and without HZ/su in healthy males and females at age 50-80 years. Model outcome measures were total cost, HZ cases, and HZ-associated quality-adjusted life-years (QALYs) loss. Incremental cost per QALY saved (ICER) by HZ/su was estimated for each age-sex group. Sensitivity analyses were performed to examine robustness of model results.
HZ/su reduced incidence of HZ in both males and females aged 50-80 years and the numbers needed to vaccinate to avoid one HZ case were lowest at age 60 years for males (6.05) and females (5.50). The highest QALY-saved occurred in females (0.00396 QALYs) and males (0.00379 QALYs) who were vaccinated at 60 years old. The ICERs were lowest at age 60-70 years for both genders. Using 1× gross domestic product per capita of Hong Kong (USD46,153) as willingness-to-pay threshold, HZ/su vaccine was accepted to be cost-effective for all female and male age groups at vaccine cost = USD160, for female aged 50-79 years and male aged 54-74 years at vaccine cost = USD200, and for female aged 59-71 years at vaccine cost = USD240.
HZ/su vaccine is more likely to be cost-effective for males and females aged between 60-70 years than the extreme age groups (less than 60 years and older than 70 years) in Hong Kong. The age range for cost-effective acceptance of HZ/su vaccine appears to be broader in females than males given the same vaccine cost and willingness-to-pay threshold.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The structural and functional integrity of the retinal pigment epithelium (RPE) is fundamental for maintaining the function of the neuroretina. These specialized cells form a polarized monolayer that ...acts as the retinal–blood barrier, separating two distinct environments with highly specialized functions: photoreceptors of the neuroretina at the apical side and Bruch's membrane/highly vascularized choriocapillaris at the basal side. The polarized nature of the RPE is essential for the health of these two regions, not only in nutrient and waste transport but also in the synthesis and directional secretion of proteins required in maintaining retinal homoeostasis and function. Although multiple malfunctions within the RPE cells have been associated with development of age‐related macular degeneration (AMD), the leading cause of legal blindness, clear causative processes have not yet been conclusively characterized at the molecular and cellular level. This article focuses on the involvement of directionally secreted RPE proteins in normal functioning of the retina and on the potential association of incorrect RPE protein secretion with development of AMD. Understanding the importance of RPE polarity and the correct secretion of essential structural and regulatory components emerge as critical factors for the development of novel therapeutic strategies targeting AMD.
The question of whether language affects perception has been debated largely on the basis of cross-language data, without considering the functional organization of the brain. The nature of this ...neural organization predicts that, if language affects perception, it should do so more in the right visual field than in the left visual field, an idea unexamined in the debate. Here, we find support for this proposal in lateralized color discrimination tasks. Reaction times to targets in the right visual field were faster when the target and distractor colors had different names; in contrast, reaction times to targets in the left visual field were not affected by the names of the target and distractor colors. Moreover, this pattern was disrupted when participants performed a secondary task that engaged verbal working memory but not a task making comparable demands on spatial working memory. It appears that people view the right (but not the left) half of their visual world through the lens of their native language, providing an unexpected resolution to the language-and-thought debate.
Previous studies have shown that the effect of language on categorical perception of color is stronger when stimuli are presented in the right visual field than in the left. To examine whether this ...lateralized effect occurs preattentively at an early stage of processing, we monitored the visual mismatch negativity, which is a component of the event-related potential of the brain to an unfamiliar stimulus among a temporally presented series of stimuli. In the oddball paradigm we used, the deviant stimuli were unrelated to the explicit task. A significant interaction between color-pair type (within-category vs. between-category) and visual field (left vs. right) was found. The amplitude of the visual mismatch negativity component evoked by the within-category deviant was significantly smaller than that evoked by the between-category deviant when displayed in the right visual field, but no such difference was observed for the left visual field. This result constitutes electroencephalographic evidence that the lateralized Whorf effect per se occurs out of awareness and at an early stage of processing.
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