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Deep convection in the Asian summer monsoon is a significant transport process for lifting pollutants from the planetary boundary layer to the tropopause level. This process enables efficient injection into the stratosphere of reactive species such as chlorinated very-short-lived substances (Cl-VSLSs) that deplete ozone. Past studies of convective transport associated with the Asian summer monsoon have focused mostly on the south Asian summer monsoon. Airborne observations reported in this work identify the East Asian summer monsoon convection as an effective transport pathway that carried record-breaking levels of ozone-depleting Cl-VSLSs (mean organic chlorine from these VSLSs ~500 ppt) to the base of the stratosphere. These unique observations show total organic chlorine from VSLSs in the lower stratosphere over the Asian monsoon tropopause to be more than twice that previously reported over the tropical tropopause. Considering the recently observed increase in Cl-VSLS emissions and the ongoing strengthening of the East Asian summer monsoon under global warming, our results highlight that a reevaluation of the contribution of Cl-VSLS injection via the Asian monsoon to the total stratospheric chlorine budget is warranted.
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Protracted droughts lasting years to decades constitute severe threats to human welfare across the Indian subcontinent. Such events are, however, rare during the instrumental period (ca. since 1871 CE). In contrast, the historic documentary evidence indicates the repeated occurrences of protracted droughts in the region during the preinstrumental period implying that either the instrumental observations underestimate the full spectrum of monsoon variability or the historic accounts overestimate the severity and duration of the past droughts. Here we present a temporally precise speleothem-based oxygen isotope reconstruction of the Indian summer monsoon precipitation variability from Mawmluh cave located in northeast India. Our data reveal that protracted droughts, embedded within multidecadal intervals of reduced monsoon rainfall, frequently occurred over the past millennium. These extreme events are in striking temporal synchrony with the historically documented droughts, famines, mass mortality events, and geopolitical changes in the Indian subcontinent. Our findings necessitate reconsideration of the region's current water resources, sustainability, and mitigation policies that discount the possibility of protracted droughts in the future.
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Tempestades Ciclônicas , Secas , Condições Sociais , Humanos , Índia , Isótopos de Oxigênio , Chuva , Estações do AnoRESUMO
SignificanceUnderstanding the drivers of South Asian monsoon intensity is pivotal for improving climate forecasting under global warming scenarios. Solar insolation is assumed to be the dominant driver of monsoon variability in warm climate regimes, but this has not been verified by proxy data. We report a South Asian monsoon rainfall record spanning the last â¼130 kyr in the Ganges-Brahmaputra-Meghna river catchment. Our multiproxy data reveal that the South Asian monsoon was weaker during the Last Interglacial (130 to 115 ka)-despite higher insolation-than during the Holocene (11.6 ka to present), thus questioning the widely accepted model assumption. Our work implies that Indian Ocean warming may increase the occurrence of severe monsoon failures in South Asia.
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While some established undergraduate summer programs are effective across many institutions, these programs may only be available to some principal investigators or may not fully address the diverse needs of incoming undergraduates. This article outlines a 10-week science, technology, engineering, mathematics, and medicine (STEMM) education program designed to prepare undergraduate students for graduate school through a unique model incorporating mentoring dyads and triads, cultural exchanges, and diverse activities while emphasizing critical thinking, research skills, and cultural sensitivity. Specifically, we offer a straightforward and adaptable guide that we have used for mentoring undergraduate students in a laboratory focused on mitochondria and microscopy, but which may be customized for other disciplines. Key components include self-guided projects, journal clubs, various weekly activities such as mindfulness training and laboratory techniques, and a focus on individual and cultural expression. Beyond this unique format, this 10-week program also seeks to offer an intensive research program that emulates graduate-level experiences, offering an immersive environment for personal and professional development, which has led to numerous achievements for past students, including publications and award-winning posters.
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Engenharia , Humanos , Engenharia/educação , Estudantes , Ciência/educação , Matemática/educação , Tecnologia/educação , Currículo , Universidades , Tutoria/métodosRESUMO
Evergreen broad-leaved forests (EBLFs) are dominated by a monsoon climate and form a distinct biome in East Asia with notably high biodiversity. However, the origin and evolution of East Asian EBLFs (EAEBLFs) remain elusive despite the estimation of divergence times for various representative lineages. Using 72 selected generic-level characteristic lineages, we constructed an integrated lineage accumulation rate (LAR) curve based on their crown ages. According to the crown-based LAR, the EAEBLF origin was identified at least as the early Oligocene (c. 31.8 million years ago (Ma)). The accumulation rate of the characteristic genera peaked at 25.2 and 6.4 Ma, coinciding with the two intensification periods of the Asian monsoon at the Oligocene - Miocene and the Miocene - Pliocene boundaries, respectively. Moreover, the LAR was highly correlated with precipitation in the EAEBLF region and negatively to global temperature, as revealed through time-lag cross-correlation analyses. An early Oligocene origin is suggested for EAEBLFs, bridging the gap between paleobotanical and molecular dating studies and solving conflicts among previous estimates based on individual representative lineages. The strong correlation between the crown-based LAR and the precipitation brought about by the Asian monsoon emphasizes its irreplaceable role in the origin and development of EAEBLFs.
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Evolução Biológica , Florestas , Ásia Oriental , Biodiversidade , Filogenia , Folhas de Planta/anatomia & histologia , Árvores/fisiologiaRESUMO
BACKGROUND: Seasonal variation and sunlight exposure can impact serum vitamin D levels, potentially influencing lupus symptoms. We investigated seasonal vitamin D levels and their correlation with clinical manifestations and disease activity in systemic lupus erythematosus (SLE). METHODS: Serum 25(OH) vitamin D3 (25(OH)D3) levels were categorised as deficient (25(OH)D3 < 10 ng/mL), insufficient (10-30 ng/mL) and sufficiency (>30 ng/mL) in participants analysed in winter (n = 407) and summer (n = 377). Logistic regression analysis was performed to assess the impact of vitamin D levels on achieving a lupus low disease activity state (LLDAS), stratified by season. RESULTS: The mean serum 25(OH)D3 levels differed significantly between the winter and summer measurement groups (22.4 vs. 24.2 ng/mL; p = .018). The prevalences of vitamin D deficiency, insufficiency and sufficiency in the winter group were 12.8%, 66.6% and 20.6%, respectively, compared with 4.5%, 67.9% and 27.6% in the summer group. Achieving LLDAS was highest in the vitamin D sufficiency group (winter: 56.6%, summer: 55%) and lowest in the vitamin D deficiency group (winter: 15.4%, summer: 13.6%), with significant differences (all p < .001). Multivariate analysis identified SLE disease activity index ≤4, normal anti-double-stranded DNA and vitamin D sufficiency as significant factors for achieving LLDAS in both seasons. CONCLUSIONS: Sufficient vitamin D levels are important for achieving LLDAS in patients with SLE during winter and summer. Therefore, physicians should pay attention to the adequacy of vitamin D levels and consider recommending vitamin D supplementation for patients with vitamin D insufficiency.
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Lúpus Eritematoso Sistêmico , Deficiência de Vitamina D , Humanos , Vitamina D , Estações do Ano , Deficiência de Vitamina D/epidemiologia , Lúpus Eritematoso Sistêmico/epidemiologia , VitaminasRESUMO
Climate change predictions suggest that arctic and subarctic ecosystems will be particularly affected by rising temperatures and extreme weather events, including severe heat waves. Temperature is one of the most important environmental factors controlling and regulating microbial decomposition in soils; therefore, it is critical to understand its impact on soil microorganisms and their feedback to climate warming. We conducted a warming experiment in a subarctic birch forest in North Sweden to test the effects of summer heat waves on the thermal trait distributions that define the temperature dependences for microbial growth and respiration. We also determined the microbial temperature dependences 10 and 12 months after the heat wave simulation had ended to investigate the persistence of the thermal trait shifts. As a result of warming, the bacterial growth temperature dependence shifted to become warm-adapted, with a similar trend for fungal growth. For respiration, there was no shift in the temperature dependence. The shifts in thermal traits were not accompanied by changes in α- or ß-diversity of the microbial community. Warming increased the fungal-to-bacterial growth ratio by 33% and decreased the microbial carbon use efficiency by 35%, and both these effects were caused by the reduction in moisture the warming treatments caused, while there was no evidence that substrate depletion had altered microbial processes. The warm-shifted bacterial thermal traits were partially restored within one winter but only fully recovered to match ambient conditions after 1 year. To conclude, a summer heat wave in the Subarctic resulted in (i) shifts in microbial thermal trait distributions; (ii) lower microbial process rates caused by decreased moisture, not substrate depletion; and (iii) no detectable link between the microbial thermal trait shifts and community composition changes.
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Ecossistema , Temperatura Alta , Microbiologia do Solo , Mudança Climática , Temperatura , Solo/química , CarbonoRESUMO
Competition for resources and space can drive forage selection of large herbivores from the bite through the landscape scale. Animal behaviour and foraging patterns are also influenced by abiotic and biotic factors. Fine-scale mechanisms of density-dependent foraging at the bite scale are likely consistent with density-dependent behavioural patterns observed at broader scales, but few studies have directly tested this assertion. Here, we tested if space use intensity, a proxy of spatiotemporal density, affects foraging mechanisms at fine spatial scales similarly to density-dependent effects observed at broader scales in caribou. We specifically assessed how behavioural choices are affected by space use intensity and environmental processes using behavioural state and forage selection data from caribou (Rangifer tarandus granti) observed from GPS video-camera collars using a multivariate discrete-choice modelling framework. We found that the probability of eating shrubs increased with increasing caribou space use intensity and cover of Salix spp. shrubs, whereas the probability of eating lichen decreased. Insects also affected fine-scale foraging behaviour by reducing the overall probability of eating. Strong eastward winds mitigated negative effects of insects and resulted in higher probabilities of eating lichen. At last, caribou exhibited foraging functional responses wherein their probability of selecting each food type increased as the availability (% cover) of that food increased. Space use intensity signals of fine-scale foraging were consistent with density-dependent responses observed at larger scales and with recent evidence suggesting declining reproductive rates in the same caribou population. Our results highlight potential risks of overgrazing on sensitive forage species such as lichen. Remote investigation of the functional responses of foraging behaviours provides exciting future applications where spatial models can identify high-quality habitats for conservation.
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Herbivoria , Densidade Demográfica , Rena , Animais , Rena/fisiologia , Comportamento Alimentar , Modelos Biológicos , Comportamento de Escolha , EcossistemaRESUMO
PREMISE: Vertical surfaces in urban environments represent a potential expansion of niche space for lithophytic fern species. There are, however, few records of differential success rates of fern species in urban environments. METHODS: The occurrence rates of 16 lithophytic fern species native to the northeastern USA in 14 biomes, including four urban environments differentiated by percentage of impervious surfaces, were evaluated. In addition, the natural macroclimatic ranges of these species were analyzed to test whether significant differences existed in climatic tolerance between species that occur in urban environments and species that do not. RESULTS: Three species appear to preferentially occur in urban environments, two species may facultatively occur in urban environments, and the remaining 11 species preferentially occur in nondeveloped rural environments. The natural range of fern species that occur in urban environments had higher summer temperatures than the range of species that do not, whereas other macroclimatic variables, notably winter temperatures and precipitation, were less important or insignificant. CONCLUSIONS: Vertical surfaces in urban environments may represent novel niche space for some native lithophytic fern species in northeastern USA. However, success in this environment depends, in part, on tolerance of the urban heat island effect, especially heating of impervious surfaces in summer.
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Ecossistema , Gleiquênias , Gleiquênias/fisiologia , Clima , Cidades , Estações do Ano , New EnglandRESUMO
Seasonal changes in environmental conditions drive phenology, i.e., the annual timing of biological events ranging from the individual to the ecosystem. Phenological patterns and successional abundance cycles have been particularly well studied in temperate freshwater systems, showing strong and predictable synchrony with seasonal changes. However, seasonal successional changes in the abundance of parasites or their infection levels in aquatic hosts have not yet been shown to follow universal patterns. Here, using a compilation of several hundred estimates of spring-to-summer changes in infection by trematodes in their intermediate and definitive hosts, spanning multiple species and habitats, we test for general patterns of seasonal (temperature) driven changes in infection levels. The data include almost as many decreases in infection levels from spring to summer as there are increases, across different host types. Our results reveal that the magnitude of the spring-to-summer change in temperature had a weak positive effect on the concurrent change in prevalence of infection in first intermediate hosts, but no effect on the change in prevalence or abundance of infection in second intermediate or definitive hosts. This was true across habitat types and host taxa, indicating no universal effect of seasonal temperature increase on trematode infections. This surprising variation across systems suggests a predominance of idiosyncratic and species-specific responses in trematode infection levels, at odds with any clear phenological or successional pattern. We discuss possible reasons for the minimal and variable effect of seasonal temperature regimes, and emphasise the challenges this poses for predicting ecosystem responses to future climate change.
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Ecossistema , Infecções por Trematódeos , Humanos , Estações do Ano , Temperatura , Mudança ClimáticaRESUMO
Plant nutrient uptake and productivity are driven by a multitude of factors that have been modified by human activities, like climate change and the activity of decomposers. However, interactive effects of climate change and key decomposer groups like earthworms have rarely been studied. In a field microcosm experiment, we investigated the effects of a mean future climate scenario with warming (+ 0.50 °C to + 0.62 °C) and altered precipitation (+ 10% in spring and autumn, - 20% in summer) and earthworms (anecic-two Lumbricus terrestris, endogeic-four Allolobophora chlorotica and both together within 10 cm diameter tubes) on plant biomass and stoichiometry in two land-use types (intensively used meadow and conventional farming). We found little evidence for earthworm effects on aboveground biomass. However, future climate increased above- (+40.9%) and belowground biomass (+44.7%) of grass communities, which was mainly driven by production of the dominant Festulolium species during non-summer drought periods, but decreased the aboveground biomass (- 36.9%) of winter wheat. Projected climate change and earthworms interactively affected the N content and C:N ratio of grasses. Earthworms enhanced the N content (+1.2%) thereby decreasing the C:N ratio (- 4.1%) in grasses, but only under ambient climate conditions. The future climate treatment generally decreased the N content of grasses (aboveground: - 1.1%, belowground: - 0.15%) and winter wheat (- 0.14%), resulting in an increase in C:N ratio of grasses (aboveground: + 4.2%, belowground: +6.3%) and wheat (+5.9%). Our results suggest that climate change diminishes the positive effects of earthworms on plant nutrient uptakes due to soil water deficit, especially during summer drought.
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Ecossistema , Oligoquetos , Humanos , Animais , Oligoquetos/fisiologia , Biomassa , Plantas , Poaceae , SoloRESUMO
Asian summer monsoon (ASM) variability and its long-term ecological and societal impacts extending back to Neolithic times are poorly understood due to a lack of high-resolution climate proxy data. Here, we present a precisely dated and well-calibrated tree-ring stable isotope chronology from the Tibetan Plateau with 1- to 5-y resolution that reflects high- to low-frequency ASM variability from 4680 BCE to 2011 CE. Superimposed on a persistent drying trend since the mid-Holocene, a rapid decrease in moisture availability between â¼2000 and â¼1500 BCE caused a dry hydroclimatic regime from â¼1675 to â¼1185 BCE, with mean precipitation estimated at 42 ± 4% and 5 ± 2% lower than during the mid-Holocene and the instrumental period, respectively. This second-millennium-BCE megadrought marks the mid-to late Holocene transition, during which regional forests declined and enhanced aeolian activity affected northern Chinese ecosystems. We argue that this abrupt aridification starting â¼2000 BCE contributed to the shift of Neolithic cultures in northern China and likely triggered human migration and societal transformation.
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Thermal indices and thermal comfort maps have great importance in developing health-minded climate action strategies and livable urban layouts. Especially in cities where vulnerability to heatwaves is high, it is necessary to detect the most appropriate indicators for the regional characteristics and action planning with respect to thermal comfort. The aim of the study is to examine thermal indices as indicators of regional climate characteristics by relating to meteorological parameters and spatial features. Atmospheric variables including air temperature, wind speed, cloud cover, and relative humidity data were obtained from 30 meteorological stations located in districts having different climatic features. Heat stress levels for apparent temperature (AT), heat index (HI), wet bulb globe temperature (WBGT), physiological equivalent temperature (PET), universal thermal climate index (UTCI), and perceived temperature (PT) indices were calculated and associated with meteorological parameters. Thermal comfort maps have been created with the daily mean and maximum values of all indices. As a result, the meteorological parameters with the strongest correlation with all thermal indices are air temperature (Ta) with r = 0.89 ± 0.01 and mean radiant temperature (Tmrt) with r = 0.75 ± 0.16. The differences in thermal stress levels over the city have been distinctively observed in the ATmax, PETmax, and PTmax maps, which are generated by the daily maximum values of the indices. Çatalca, where forests cover large areas compared to highly urbanized districts, has the lowest heat stress defined by all indices.
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Estações do Ano , Sensação Térmica , Humanos , Turquia , Temperatura , CidadesRESUMO
Nanoliposomes are drug delivery systems that improve bioavailability by encapsulating therapeutic agents. The main objective of this study was to investigate the effects of nanoliposomal (NL) formulation on enhancing the bioavailability of essential oil. The essential oil of Satureja hortensis (SHO) was encapsulated in nanoliposomes (SHNLs). Physicochemical characterizations of NL formulations (size, charge, polydispersity index [PDI]) were evaluated by dynamic light scattering technique. The nanoliposome encapsulation efficiency (EE) was calculated as 89.90%. The prepared bionanosystems demonstrated significant antibacterial activities against Escherichia coli ATCC 10536, Pseudomonas aeruginosa ATCC 15442, and Staphylococcus aureus ATCC as determined by the agar diffusion method and microdilution tests. Minimum inhibitory concentration (MIC) values for SHNLs were found to be 5.187 µg/µL for E. coli and 2.59 µg/µL for both P. aeruginosa and S. aureus. Importantly, despite the lower substance content, both SHNLs and SHO exhibited comparable antibacterial activity against all tested strains. Furthermore, in order to determine the toxicity profile and possible effects on DNA damage or repair both the genotoxic and antigenotoxic effects of SHNLs were assessed using the cytokinesis-blocked micronucleus (CBMN) method in human lymphocyte cultures. The experimental data collectively indicate that the NL formulation of the S. hortensis essential oil enhances antibacterial activities and provides genoprotective effects against DNA damage. This highlights the significance of liposomal formulations of antioxidants in augmenting their biological activity. The results indicate that SHNLs can be a safe antibacterial agent for the pharmaceutical industry.
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Boreal lakes experience pronounced seasonal variation in abiotic factors, especially light, temperature, and oxygen. A deep boreal humic lake was sampled year-round to test putative changes in total fish catch, species composition, catch-per-unit-effort (CPUE), habitat use, fish size, and condition. Monthly sampling was conducted in Lake Pääjärvi, southern Finland, during one full year in 2020-2021 as well as in March and August 2021 and 2022. The fish community was dominated by cyprinid species in all months, but the percentage of percid fish caught increased during the warm summer period. Most fish were caught in littoral habitats and the highest catches occurred in summer, but some species (e.g., ruffe, Gymnocephalus cernua, and pikeperch, Sander lucioperca) remained abundant in the winter catch. The body size of fish was larger in the winter catch, while condition factor was higher in summer for most species. Fish species proportions in total catch, CPUE, and average size of fish were closest to the annual mean values in September, which may be used as the optimal period to monitor fish communities of similar deep boreal lakes. Our findings highlight the need for year-round research to reveal the impacts of rising temperatures and diminishing ice-covered periods in fish communities and lake food webs.
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Arkansas has a high cancer burden, and a pressing need exists for more medical students to pursue oncology as a career. The Partnership in Cancer Research (PCAR) program provides a summer research experience at the University of Arkansas for Medical Sciences for 12 medical students who have completed their first year of medical training. A majority of participants spend time pursuing cancer research in basic science, clinical, or community-based research. Students report on their research progress in an interactive "Live from the Lab!" series and assemble a final poster presentation describing their findings. Other activities include participation in a moderated, cancer-patient support group online, lecture series on cancer topics, medical simulations, palliative care clinic visit, "Death Over Dinner" event, and an entrepreneurship competition. Students completed surveys over PCAR's first 2 years in operation to evaluate all aspects of the program. Surveys reveal that students enthusiastically embraced the program in its entirety. This was especially true of the medical simulations which received the highest evaluations. Most significantly, surveys revealed that the program increased cancer knowledge and participant confidence to perform cancer research.
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Neoplasias , Estudantes de Medicina , Humanos , Currículo , Pesquisa , Oncologia/educação , Neoplasias/terapia , Avaliação de Programas e Projetos de SaúdeRESUMO
While literature suggests that youth physical activity (PA) behaviors are affected by network influences, less is known about network influences on perceived skill competency, a component of physical literacy and self-efficacy. This study aims to provide an understanding of potential network characteristics which are associated with youth PA skill competency. Youth (n = 158) between the ages of 8 and 12 years recruited from two summer care programs (i.e., Boys & Girls Clubs) participated in researcher-administered surveys. Youth self-reported their age, sex, involvement in team sports, weekly PA, and skill competency assessed using a version of the PLAYself measure. Youth were also asked to report up to five people in the summer program and five out of the program with whom they interacted the most. Linear regression was used to evaluate associations between skill competency and demographics, PA, and social network characteristics. Skill competency was significantly associated (R2 = .17) with age (ß = -.06, p = .01), sex (ß = -.06, p = .01), sports team involvement (ß = .16, p < .001), and weekly PA (ß = -.20, p < .001). Skill competency was also significantly associated with the number of connections with whom the youth played frequently (ß = .09, p < .001), the number of connections that helped the youth to be active (ß = .18, p < .001), and the heterogeneity of the type of relationships within the youth's network (ß = .11, p < .001). Skill competency scores were significantly associated with both individual variables and social network composition. In addition, youth with networks comprising several types of relationships (heterogeneity) reported a significantly high skill competency. PA interventions can be most effective when considering the reinforcing aspects of networks and skill competency.
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The need for a robust public health system in the United States is critical for safeguarding population health. However, current data suggest an insufficient number of individuals entering or staying in the governmental public health workforce. Expanding the public health pipeline requires creative thinking about recruitment and training activities. To attract students to public health and other health-related fields, including medicine, one institution in the Southeast recently initiated the Public Health Influencers Summer Institute (PHISI), a program that addresses the beginning of the career development continuum: recruitment of high school students. For this investigation, we reviewed evaluation data of the PHISI and provided descriptive analyses and selected quotes to reflect student learning. Participants reported increased familiarity with all public health topics after participating in the program, with the greatest increases in public health policy and social determinants of health. In addition, all participants reported increased or significantly increased understanding of public health after participating in the program. While interest in the field of public health increased due to the COVID-19 pandemic, there are not enough individuals entering or staying in the public health workforce, leaving a critical shortfall. Introducing high school students to the field of public health may increase their interest in entering the public health workforce in the future, thereby strengthening the overall public health infrastructure. We propose that the PHISI may be an innovative strategy for increasing both the number and diversity of students interested in pursuing a career in public health.
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Tea is the second largest nonalcoholic beverage in the world due to its characteristic flavor and well-known functional properties in vitro and in vivo. Global tea production reaches 6.397 million tons in 2022 and continues to rise. Fresh tea leaves are mainly harvested in spring, whereas thousands of tons are discarded in summer and autumn. Herein, pruned tea biomass refers to abandon-plucked leaves being pruned in the non-plucking period, especially in summer and autumn. At present, no relevant concluding remarks have been made on this undervalued biomass. This review summarizes the seasonal differences of intrinsic metabolites and pays special attention to the most critical bioactive and flavor compounds, including polyphenols, theanine, and caffeine. Additionally, meaningful and profound methods to transform abandon-plucked fresh tea leaves into high-value products are reviewed. In summer and autumn, tea plants accumulate much more phenols than in spring, especially epigallocatechin gallate (galloyl catechin), anthocyanins (catechin derivatives), and proanthocyanidins (polymerized catechins). Vigorous carbon metabolism induced by high light intensity and temperature in summer and autumn also accumulates carbohydrates, such as soluble sugars and cellulose. The characteristics of abandon-plucked tea leaves make them not ideal raw materials for tea, but suitable for novel tea products like beverages and food ingredients using traditional or hybrid technologies such as enzymatic transformation, microbial fermentation, formula screening, and extraction, with the abundant polyphenols in summer and autumn tea serving as prominent flavor and bioactive contributors.
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Biomassa , Camellia sinensis , Folhas de Planta , Polifenóis , Folhas de Planta/química , Camellia sinensis/química , Polifenóis/análise , Alimento Funcional , Estações do Ano , Chá/química , Cafeína , Catequina/química , Catequina/análogos & derivados , GlutamatosRESUMO
BACKGROUND: Washing with water is not inferior to washing with soaps and detergents in children with atopic dermatitis (AD) in remission during the fall-winter seasons. We investigated whether this finding varies during summer based on the type of cleanser (soaps and detergents). METHODS: This evaluator-blinded, pragmatic, randomized, and non-inferiority study enrolled patients with AD whose eczema was controlled following regular steroid ointment application 2 days/week. For 8 ± 4 weeks, participants washed their upper and lower limbs with a cleanser on one side and with water alone on the other. Each participant chose either a weakly alkaline soap or an acidic detergent. The primary outcome was the Eczema Area and Severity Index (EASI) score at week 8 ± 4. RESULTS: The data of 43 of the 47 registered participants were analyzed. The median patient age was 44 (23-99) months; 28 and 15 participants chose weakly alkaline and acidic cleansers, respectively. At week 8 ± 4, EASI scores of the water and cleanser sides were 0.00 (0.00-0.40) and 0.15 (0.00-0.40), respectively (p = 0.74). The difference between both sides was 0.00 (-0.07 to 0.14); the limits of the 95 % confidence interval did not reach the pre-specified non-inferiority margin. No difference was observed in the median Patient-Oriented Eczema Measure score, number of additional steroid ointment applications, and occurrences of skin infections. There were no differences between the cleanser types in any of the results. CONCLUSIONS: We demonstrated that washing with water was not inferior to that with a cleanser in patients with AD in the maintenance phase during summer, regardless of the type of cleanser.