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1.
Animal ; 18(9): 101261, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39126798

RESUMO

Grazing management significantly contributes to low beef production in cow-calf systems within the Rio de la Plata native grasslands. An herbage allowance (HA) of 4 kg DM/kg BW increased the productive response of primiparous cows grazing shallow soils compared to 2.5. However, the impact of HA on metabolic changes and its association with productive response were not studied. We studied two levels of native grassland HA from -150 days relative to calving (DC) to weaning (195 DC) in spring-calving primiparous beef cows undergoing temporary weaning (TW) and flushing at 86 ±â€¯12 DC on herbage intake (HI), body condition score (BCS), BW, milk yield, calf weight, concentrations of metabolic hormones, and the probability of ovulation and pregnancy. Thirty-one heifers were assigned to HA treatments that fluctuated throughout seasons: autumn (-150 to -90 DC) at 5 and 3 kg DM/kg BW, winter (-90 to 0 DC) at 3 and 3 kg DM/kg BW, and spring-summer (0 to 195 DC) at 4 and 2 kg DM/kg BW for High and Low HA, respectively. Data were analysed using linear models and generalised linear models for continuous and categorical variables, respectively. During the autumn period, HI, insulin, IGF-I, BCS, and BW were higher in High HA than Low, despite small differences in herbage mass between HA. Throughout the winter, spring, and summer, HI, insulin, leptin, and BCS changes did not differ between HA. However, IGF-I concentrations were greater at -65 and -40 DC (84 vs 55 ±â€¯8.6 ng/mL; P < 0.05) and tended to be greater after TW in High HA than Low. The probability of ovulation did not reach significance (0.94 vs 0.75 ±â€¯0.11 for High and Low HA, respectively; P = 0.125), while the probability of pregnancy was greater in High HA than in Low HA (0.9 vs 0.61 ±â€¯0.10; P = 0.07). Ovulation probability exhibited a positive association with IGF-I concentrations at -90 and -40 DC (P < 0.05), but not postpartum. Milk yield did not differ between treatments, while calf weight was heavier at weaning in High HA cows (194 vs 178 ±â€¯3.3 kg; P < 0.05). High HA enhances autumn HI and BCS and generates a carry-over effect on IGF-I concentrations throughout winter and after TW ("metabolic memory"), explaining the better reproductive response. Moderate changes in cows' nutrition during autumn contribute to changes in metabolic status and reproductive outcomes in primiparous cows grazing moderate herbage production native grasslands.

2.
Acta Trop ; 258: 107355, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39122103

RESUMO

Migratory birds play an important role in the cross-regional transmission of zoonotic pathogens. Assessing the presence of zoonotic pathogens carried by migratory birds is critical for disease control. However, information about Blastocystis infection in the migratory birds is very limited. Thus, we conducted this study with the aim to explore the occurrence, prevalence and subtyping of Blastocystis in four breeds of migratory birds in northeastern China. From October 2022 to April 2023, a total of 427 fresh fecal samples were obtained from four breeds of migratory birds in five nature reserves in northeastern China, and screened for Blastocystis by PCR amplification. Twenty-one (4.92 %) of the studied samples were confirmed Blastocystis-positive, and two known zoonotic subtypes ST6 and ST7 were founded, with ST7 being the major subtype. Until now, we firstly reported the infection status and subtyping of Blastocystis in the migratory Greater White-Fronted Goose, White Stork, Oriental White Stork and Bean Goose in China. More importantly, these findings present further data on the genetic diversity and transmission routes of Blastocystis and further arouse public health concerns about this organism.

3.
Heliyon ; 10(15): e34866, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39145020

RESUMO

Numerous Payments for Ecosystem Services (PES) programs have been implemented simultaneously around the world but their outcomes in the literature are not consistent and their interactive effects remain understudied. The Natural Forest Conservation Program (NFCP) and Grain to Green Program (GTGP) are two largest PES programs in the world, and many studies have evaluated their effects on household income. However, the identified effects often varied across different studies and the factors explaining this variation are poorly understood. This study used linear regression and geographic detector analysis, based on questionnaire survey data from 14 giant panda natural reserves (NRs) in southwestern China, to evaluate the effects of the NFCP and GTGP on household income and the factors which moderate these effects. The results revealed that the effects of two PES programs on household income were spatially heterogeneous and enhanced by each other and livelihood activities, suggesting a synergistic interaction between policies and livelihood activities, particularly tourism. This study also found that livelihoods activities (e.g., labor migration and tourism), household capital (i.e., house area and farmland area) and demographic factors (i.e., number of labor and non-labor members), exhibit spatial heterogeneity in their effects on household income across NRs. These findings underscore the importance of considering local socioeconomic conditions and the interaction between policy and socio-economic conditions in PES program design to achieve desired outcomes, providing insights for policymakers and practitioners worldwide.

4.
Nano Lett ; 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39141437

RESUMO

The insufficient antioxidant reserves in tumor cells play a critical role in reactive oxygen species (ROS)-mediated therapeutics. Metallothionein-2 (MT-2), an intracellular cysteine-rich protein renowned for its potent antioxidant properties, is intricately involved in tumor development and correlates with a poor prognosis. Consequently, MT-2 emerges as a promising target for tumor therapy. Herein, we present the development of copper-doped carbon dots (Cu-CDs) to target MT-2 to compromise the delicate antioxidant reserves in tumor cells. These Cu-CDs with high tumor accumulation and prolonged body retention can effectively suppress tumor growth by inducing oxidative stress. Transcriptome sequencing unveils a significant decrease in MT-2 expression within the in vivo tumor samples. Further mechanical investigations demonstrate that the antitumor effect of Cu-CDs is intricately linked to apolipoprotein E (ApoE)-mediated downregulation of MT-2 expression and the collapse of the antioxidant system. The robust antitumor efficacy of Cu-CDs provides invaluable insights into developing MT-2-targeted nanomedicine for cancer therapies.

5.
J Environ Manage ; 365: 121645, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38959768

RESUMO

Priority ecological reserves (PER) aim to protect areas with significant ecological value and crucial ecological functions, optimizing resource allocation to maximize the benefits of ecological conservation. However, most previous studies have considered only ecosystem services (ESs) in delineating PER, neglecting eco-environmental quality (EEQ). This study used the Remote Sensing-based Ecological Index (RSEI) to represent EEQ and combined it with ESs to delineate PER at the county scale in the Yellow River Basin (YRB). Additionally, it employed Multiscale Geographically Weighted Regression to identify the driving factors influencing the ESs and EEQ of PER. The results showed that: (1) From 2000 to 2020, both RSEI and the Comprehensive ESs (CES) in the YRB exhibited a fluctuating upward trend; (2) Three types of PER were extracted, with ESs reserve mainly distributed in the upstream region, EEQ reserve primarily in the middle and lower reaches, and integrated ecological reserve mainly in the midstream region, all dominated by vegetation land-use types; (3) Within the extracted PER, RSEI was mainly influenced by soil, aspect, population (pop), PM2.5, temperature (tmp), and potential evapotranspiration (pet), while CES was affected by soil, pop, PM2.5, slope, tmp, precipitation, and pet. To enhance the EEQ and ESs of the YRB, it was recommended to incorporate at least 105,379 km2 into the existing protected areas in the YRB. These areas should be subdivided based on their ecological status, with specific management measures for different types of PER. This study provides recommendations for environmental protection and land planning in the YRB, actively responding to current policies on high-quality development and ecological environmental protection in the YRB.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Rios , Monitoramento Ambiental , Ecologia , China
6.
Heliyon ; 10(12): e33017, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-39021946

RESUMO

The complex iron oxide copper and gold (IOCG) Sin Quyen deposit in northern Vietnam is known as hydrothermal veins and multi-stages of mineralization. Thus, it is complicated to make a probabilistic 3D geometric model using traditional methods and to predict the hidden mineral potential. In this study, computer modeling with nearly 8000 archival data was recorded from 146 boreholes within the study area, and the chemical analysis was done on 40 samples. The 3D block model was constructed using geological structure, optimal parameters, and computational tools approach to the 3D geometric models of surface and ore bodies distribution. The Cu and Ag reserves were estimated based on the 3D geometric models. The total reserve of all ore bodies at the current depth was recorded at 540000 and 25 tons for Cu and Ag, respectively. In the study area, almost all ore bodies were observed as hydrothermal vein types, extending in Northwest-Southeast strikes and dipping around 750 m, closest to the geological observation. The mineralization characteristics of the study area are controlled by left-lateral zipper tectonic activity and faults. Based on tectonic and the 3D geometric model characteristics, the Cu ore bodies are trending continuously to more than 300 m depth at the Southeast of Ngoi Phat stream, while the Northwest shows no signs.

7.
Trop Med Health ; 52(1): 48, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39030649

RESUMO

BACKGROUND: Despite urban (domestic dog) rabies cycles being the main target for rabies elimination by 2030, sylvatic (wildlife) rabies cycles can act as rabies spillovers especially in settlements contiguous to wildlife reserves. Rural communities next to wildlife reserves are characterized by unique socio-demographic and cultural practices including bat consumption, hunting for bushmeat, and non-vaccination of hunting dogs against rabies among others. This study aimed to compare the knowledge, attitudes, and practices (KAPs) related to rabies transmission and prevention in the three districts of Uganda; (1) Nwoya, neighboring Murchison Falls National Park (MFNP) in the north, (2) Kamwenge neighboring Kibaale National Park (KNP), Queen Elizabeth National Park (QENP) and Katonga Game Reserve (KGR) in the west, and (3) Bukedea, neighboring Pian Upe Game Reserve (PUGR) in the east of Uganda. METHODS: A community-based cross-sectional survey was conducted in settlements contiguous to these wildlife reserves. Using a semi-structured questionnaire, data were collected from 843 households owning dogs and livestock. Data were collected between the months of January and April 2023. Stratified univariate analyses by district were carried out using the Chi-square test for independence and Fisher's exact test to compare KAPs in the three study districts. RESULTS: The median age of study participants was 42 years (Q1, Q3 = 30, 52) with males comprising the majority (67%, n = 562). The key findings revealed that participants from the Nwoya district in the north (MFNP) had little knowledge about rabies epidemiology (8.5%, n = 25), only 64% (n = 187) of them knew its signs and symptoms such as a rabid dog presenting with aggressiveness and showed negative attitudes towards prevention measures (15.3%, n = 45). Participants in the Kamwenge district-west (KNP, QENP, and KGR) had little knowledge and negative attitude towards wildlife-human interaction pertaining to rabies transmission and prevention especially those with no or primary level of education (20.9%, n = 27) while participants from Bukedea in the east (PUGR) had remarkedly poor practices towards rabies transmission, prevention, and control (37.8%, n = 114). CONCLUSIONS: Rabies from sylvatic cycles remains a neglected public health threat in rural communities surrounding national parks and game reserves in Uganda. Our study findings highlight key gaps in knowledge, attitudes, and practices related to rabies transmission and prevention among such communities. Communication and action between veterinary services, wildlife authority, public health teams, social science and community leaders through available community platforms is key in addressing rabies among the sympatric at-risk communities in Uganda.

8.
Huan Jing Ke Xue ; 45(7): 4164-4176, 2024 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-39022963

RESUMO

Studying the response relationship and spatial distribution characteristics of carbon reserve and land use change and predicting the change trend of carbon reserve caused by the change of land use type in the future can provide some reference for watershed policy formulation, land use structure adjustment, and the realization of the "two-carbon" goal. Based on the land use data from 2000, 2010, and 2020, the InVEST model was used to calculate carbon reserves and analyze the change characteristics and to simulate the land use change and its impact on carbon reserves in natural development, urban development, and ecological protection in 2030 with the help of the PLUS model. The study found that ① the main land types in the Shiyang River Basin from 2000 to 2020 were cultivated land, grassland, and unused land. The area of cultivated land, water area, and construction land in the Shiyang River Basin showed a significant increasing trend, and the construction land area increased the most. ② In the natural development scenario of 2030, cultivated land, water area, and construction all increased by 6.15%, 9.56%, and 29.9%, respectively. In the urban development scenario, the area of construction land increased the most. Compared with that in the other two scenarios, the area of forest land and grassland increased in the ecological protection scenarios. ③ The carbon reserves of the Shiyang River Basin from 2000 to 2020 showed a steady increase, with an overall increase of 0.035×108 t. The increased carbon reserves were mainly due to the increase in cultivated land area. ④ In 2030, the carbon reserves of the Shiyang River Basin showed an increasing trend in all three scenarios. The carbon reserves in the three scenarios were 5.65×108, 5.64×108,and 5.73×108 t, respectively, with the largest increase in carbon reserves in the ecological conservation scenario, mainly due to the increase in grassland and woodland. The results showed that the expansion of construction land was the main cause of the loss of carbon reserves. If effective ecological protection measures are taken, the carbon reserves in the Shiyang River Basin will be improved, and the problem of the loss of carbon reserves caused by economic development can be solved.

9.
New Phytol ; 243(5): 1855-1869, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38962989

RESUMO

Grain filling in maize (Zea mays) is intricately linked to cell development, involving the regulation of genes responsible for the biosynthesis of storage reserves (starch, proteins, and lipids) and phytohormones. However, the regulatory network coordinating these biological functions remains unclear. In this study, we identified 1744 high-confidence target genes co-regulated by the transcription factors (TFs) ZmNAC128 and ZmNAC130 (ZmNAC128/130) through chromatin immunoprecipitation sequencing coupled with RNA-seq analysis in the zmnac128/130 loss-of-function mutants. We further constructed a hierarchical regulatory network using DNA affinity purification sequencing analysis of downstream TFs regulated by ZmNAC128/130. In addition to target genes involved in the biosynthesis of starch and zeins, we discovered novel target genes of ZmNAC128/130 involved in the biosynthesis of lipids and indole-3-acetic acid (IAA). Consistently, the number of oil bodies, as well as the contents of triacylglycerol, and IAA were significantly reduced in zmnac128/130. The hierarchical regulatory network centered by ZmNAC128/130 revealed a significant overlap between the direct target genes of ZmNAC128/130 and their downstream TFs, particularly in regulating the biosynthesis of storage reserves and IAA. Our results indicated that the biosynthesis of storage reserves and IAA is coordinated by a multi-TFs hierarchical regulatory network in maize endosperm.


Assuntos
Endosperma , Regulação da Expressão Gênica de Plantas , Redes Reguladoras de Genes , Ácidos Indolacéticos , Proteínas de Plantas , Fatores de Transcrição , Zea mays , Zea mays/genética , Zea mays/metabolismo , Ácidos Indolacéticos/metabolismo , Endosperma/metabolismo , Endosperma/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Genes de Plantas , Mutação/genética , Amido/metabolismo , Amido/biossíntese
10.
Aquat Toxicol ; 273: 107013, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38996481

RESUMO

Insects with aquatic larval and terrestrial adult life stages are a key component of coupled aquatic-terrestrial ecosystems. Thus, stressors applied to water bodies adversely affecting those larvae have the potential to influence the riparian zone through altered emergence, with differences in prey availability, timing, or nutrition. In this study, the common model organism Chironomus riparius, a species of Chironomidae (Diptera), was used. This selection was further motivated by its wide distribution in European freshwaters and its importance as prey for terrestrial predators. A stressor of high importance in this context is the globally used mosquito control agent Bacillus thuringiensis var. israelensis (Bti) which has been shown to affect Chironomidae. Here, we investigated the ability of chironomid populations to adapt to a regularly applied stressor, leading to a reduced impact of Bti. Therefore, the initial sensitivity of laboratory populations of C. riparius was investigated under the influence of field-relevant Bti treatments (three doses × two application days) and different food sources (high-quality TetraMin vs. low-quality Spirulina). Following a chronic exposure to Bti over six months, the sensitivity of pre-exposed and naïve populations was re-evaluated. Food quality had a strong impact on emergence timing and nutrient content. In addition, alterations in emergence time as well as protein and lipid contents of chronically exposed populations indicated a selection for individuals of advantageous energetics, potentially leading to a more efficient development while combating Bti. Signs of adaptation could be confirmed in five out of 36 tested scenarios suggesting adaptation to Bti at the population level. Adaptive responses of one or several species could theoretically (via eco-evolutionary dynamics) result in a community shift, favouring the prevalence of Bti-tolerant species. (In)direct effects of Bti and the adaptive responses at both population and community levels could affect higher trophic levels and may determine the fate of meta-ecosystems.


Assuntos
Adaptação Fisiológica , Bacillus thuringiensis , Chironomidae , Larva , Animais , Chironomidae/efeitos dos fármacos , Chironomidae/fisiologia , Larva/efeitos dos fármacos , Nutrientes , Poluentes Químicos da Água/toxicidade , Fenótipo
11.
Mar Pollut Bull ; 205: 116631, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38917503

RESUMO

The causes of the physiological effects of microplastic pollution, potentially harming reef-building corals, are unclear. Reasons might include increased energy demands for handling particles and immune reactions. This study is among the first assessing the effects of long-term microplastic exposure on coral physiology at realistic concentrations (200 polyethylene particles L-1). The coral species Acropora muricata, Pocillopora verrucosa, Porites lutea, and Heliopora coerulea were exposed to microplastics for 11 months, and energy reserves, metabolites, growth, and photosymbiont state were analyzed. Results showed an overall low impact on coral physiology, yet species-specific effects occurred. Specifically, H. coerulea exhibited reduced growth, P. lutea and A. muricata showed changes in photosynthetic efficiency, and A. muricata variations in taurine levels. These findings suggest that corals may possess compensatory mechanisms mitigating the effects of microplastics. However, realistic microplastic concentrations only occasionally affected corals. Yet, corals exposed to increasing pollution scenarios will likely experience more negative impacts.


Assuntos
Antozoários , Recifes de Corais , Microplásticos , Fotossíntese , Polietileno , Poluentes Químicos da Água , Animais , Antozoários/efeitos dos fármacos , Antozoários/fisiologia , Microplásticos/toxicidade , Fotossíntese/efeitos dos fármacos , Polietileno/toxicidade , Poluentes Químicos da Água/toxicidade , Monitoramento Ambiental
12.
Math Biosci Eng ; 21(5): 6123-6149, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38872572

RESUMO

In this paper, we investigate an optimal harvesting problem of a spatially explicit fishery model that was previously analyzed. On the surface, this problem looks innocent, but if parameters are set to where a singular arc occurs, two complex questions arise. The first question pertains to Fuller's phenomenon (or chattering), a phenomenon in which the optimal control possesses a singular arc that cannot be concatenated with the bang-bang arcs without prompting infinite oscillations over a finite region. 1) How do we numerically assess whether or not a problem chatters in cases when we cannot analytically prove such a phenomenon? The second question focuses on implementation of an optimal control. 2) When an optimal control has regions that are difficult to implement, how can we find alternative strategies that are both suboptimal and realistic to use? Although the former question does not apply to all optimal harvesting problems, most fishery managers should be concerned about the latter. Interestingly, for this specific problem, our techniques for answering the first question results in an answer to the the second. Our methods involve using an extended version of the switch point algorithm (SPA), which handles control problems having initial and terminal conditions on the states. In our numerical experiments, we obtain strong empirical evidence that the harvesting problem chatters, and we find three alternative harvesting strategies with fewer switches that are realistic to implement and near optimal.

13.
Ecol Lett ; 27(6): e14459, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38877751

RESUMO

Recent international agreements have strengthened and expanded commitments to protect and restore native habitats for biodiversity protection ("area-based biodiversity conservation"). Nevertheless, biodiversity conservation is hindered because how such commitments should be implemented has been strongly debated, which can lead to suboptimal habitat protection decisions. We argue that, despite the debates, there are three essential principles for area-based biodiversity conservation. These principles are related to habitat geographic coverage, amount, and connectivity. They emerge from evidence that, while large areas of nature are important and must be protected, conservation or restoration of multiple small habitat patches is also critical for global conservation, particularly in regions with high land use. We contend that the many area-based conservation initiatives expected in the coming decades should follow the principles we identify, regardless of ongoing debates. Considering the importance of biodiversity for maintenance of ecosystem services, we suggest that this would bring widespread societal benefits.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Conservação dos Recursos Naturais/métodos , Ecossistema
14.
Ecology ; 105(7): e4324, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38838008

RESUMO

We present a data set resulting from the first round of a national monitoring program of forest reserves. It contains 9538 permanent plots, distributed across 111 study sites in mainland France (including Corsica). Notably focusing on dead wood measurement, this protocol has primarily been applied in strict forest reserves and special nature reserves (sensu Bollmann & Braunisch 2013), with 68% (6494) of the plots being currently located in strict forest reserves (unmanaged) and 24.7% (2363 plots) in forests unmanaged for at least 50 years. Sites cover a large variety of ecological conditions, from lowland to subalpine forests, but with an underrepresentation of Mediterranean forests (Table 1). The protocol assesses all the stages of a tree's life cycle, from seedling to decomposed lying dead wood. On each plot, a combination of three sampling techniques was used: (1) fixed-area inventory for regeneration, standing dead trees, living trees, and coarse woody debris (CWD) with diameter over 30 cm; (2) transect lines for CWD with diameter <30 cm; and (3) fixed-angle plot method for living trees with diameter at breast height (DBH) >30 cm (using a relascopic angle of 3%). Measurements include exact tree location (azimuth, distance), species, diameter(s), tree-related microhabitats, decay stage and bark cover, and seedling cover. With ongoing climate change, the program network can also provide important information to monitor changes in forest ecosystems. It can also be used as forest management monitoring or conservation status assessment. These data are freely available for noncommercial scientific use (Creative Commons Attribution 4.0 CC BY SA 4.0) with attribution, and this paper must be cited if this material is reused.


Assuntos
Conservação dos Recursos Naturais , Florestas , Árvores , França , Árvores/fisiologia , Conservação dos Recursos Naturais/métodos , Agricultura Florestal/métodos , Monitoramento Ambiental/métodos
15.
Front Endocrinol (Lausanne) ; 15: 1369248, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38828407

RESUMO

Background: Reproduction ability requires a certain amount of body fat that is necessary for ovulation, menstruation and pregnancy. Fat tissue represents an endocrine organ with high metabolic activity as it produces adipokines such as leptin and adiponectin. Our aim is to examine potential associations between women of reproductive age's ovarian reserves and their levels of leptin and adiponectin. Method: 74 women between 19 and 40 years of age consented to take part. Based on the patterns of their ovarian reserves, the women were divided into three main groups: women with adequate ovarian reserves (AOR - Group A, n=30), women with polycystic ovary syndrome (PCOS - Group B, n=31) and women with depleted ovarian reserves (DOR - Group C, n=13). Among these groups, several biochemical and demographic parameters were statistically compared. Results: Compared to the other two groups, women with DOR had statistically higher age and follicle stimulation hormone (FSH) levels. For estradiol (E2) and thyroid-stimulating hormone (TSH), no statistically significant difference was seen between the groups. In addition, women with PCOS had higher body mass index (BMI), luteinizing hormone (LH), total testosterone (TT), 17 hydroxyprogesterone (17-OHP), dehydroepiandrosterone (DHEA), anti-Mullerian hormone (AMH), and antral follicle count (AFC) than the other two groups. In line with expectations, women with DOR also had lower levels of AMH and AFC than the other two groups. Women with PCOS had higher leptin levels than the other two groups, but there was no statistically significant difference. Women with PCOS had lower levels of adiponectin than the other groups, however the difference was not statistically significant. Conclusion: The way we classified women in our study according to their ovarian reserves is completely consistent with what has been published internationally. The ovarian reserve in women of reproductive age is not strongly correlated with leptin and adiponectin levels. For safe conclusions, more research including a greater number of samples is required.


Assuntos
Adiponectina , Leptina , Reserva Ovariana , Humanos , Feminino , Leptina/sangue , Adiponectina/sangue , Reserva Ovariana/fisiologia , Adulto , Adulto Jovem , Síndrome do Ovário Policístico/sangue , Síndrome do Ovário Policístico/metabolismo , Índice de Massa Corporal , Reprodução/fisiologia , Ovário/metabolismo
16.
Ecol Evol ; 14(5): e11336, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38711485

RESUMO

The preservation or removal of apical meristem in Leymus chinensis is contingent upon grazing intensity and has a significant impact on above- and belowground biomass, nutritive value, and sustainability of L. chinensis grassland. However, this topic remains understudied. Therefore, a manipulative trial was conducted to induce grazing defoliation through mowing, where two post-grazing heights (preservation or removal of the apical meristem) and four pre-grazing plant heights (i.e., 18, 24, 31, and 35 cm) are combined factorially to create gradients of grazing intensities, resulting in a total of eight treatments. Additionally, two identical control treatments are also incorporated. Our results showed that apical meristem removal at various pre-grazing heights resulted in varying degrees of increased grazing intensities, thereby enhancing the nutritive value of L. chinensis. However, this practice also led to detrimental effects on the plant's carbohydrates reserve as well as herbage mass. The results indicated that although defoliation in treatments involving apical meristem removal resulted in the highest number of frequent cuttings, it did not confer any advantages in terms of herbage mass and nutrient preserves, except for herbage nutritive values when compared to treatments involving apical meristem preservation. The apical meristem preservation treatments demonstrated the highest CP yield over a 2-year period compared to the apical meristem removal treatments. Furthermore, within these apical meristem preservation treatments, only when the pre-grazing height is 35 cm and post-grazing height is 17 cm, there is no significant decrease in above- and belowground biomass. This establishes this specific defoliation regime as an optimal and effective management strategy for L. chinensis grassland.

17.
Front Plant Sci ; 15: 1375958, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38766471

RESUMO

Carbohydrate reserves play a vital role in plant survival during periods of negative carbon balance. Under a carbon-limited scenario, we expect a trade-offs between carbon allocation to growth, reserves, and defense. A resulting hypothesis is that carbon allocation to reserves exhibits a coordinated variation with functional traits associated with the 'fast-slow' plant economics spectrum. We tested the relationship between non-structural carbohydrates (NSC) of tree organs and functional traits using 61 angiosperm tree species from temperate and tropical forests with phylogenetic hierarchical Bayesian models. Our results provide evidence that NSC concentrations in stems and branches are decoupled from plant functional traits. while those in roots are weakly coupled with plant functional traits. In contrast, we found that variation between NSC concentrations in leaves and the fast-slow trait spectrum was coordinated, as species with higher leaf NSC had trait values associated with resource conservative species, such as lower SLA, leaf N, and leaf P. We also detected a small effect of leaf habit on the variation of NSC concentrations in branches and roots. Efforts to predict the response of ecosystems to global change will need to integrate a suite of plant traits, such as NSC concentrations in woody organs, that are independent of the 'fast-slow' plant economics spectrum and that capture how species respond to a broad range of global change drivers.

18.
Data Brief ; 54: 110348, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38586129

RESUMO

This geospatial dataset provides a compilation of findings from an evidence-based review of site-specific resource assessments of mining and metallurgical residues. Information pertaining to location, target material, geological knowledge, extractability, resource classification and stakeholder perspectives was collected from publicly available reports, articles, academic theses, and databases. The dataset includes 44 relevant data attributes from 64 mining and metallurgical sites in 27 countries. Resource classification is available for 38 sites. The dataset can be used by evaluators of recovery projects, authorities that provide permits, as well as by decision makers in support of developing regulatory policies. The dataset facilitates future addition of sites by the research community and can be further used as a starting point to bridge the estimates on recoverable quantities to the United Nations Framework Classification (UNFC). The UNFC is a universally applicable scheme for the sustainable management of all energy, primary and secondary mineral resources. Its use is stimulated by the European Commission and is intended to be adopted by geological surveys to harmonize the data on the availability of primary and secondary raw materials in Europe in future.

19.
Heliyon ; 10(7): e28519, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38596117

RESUMO

The global climate is undergoing extraordinary changes, profoundly influencing a variety of ecological processes. Understanding the distribution patterns and predicting the future of plant diversity is crucial for biodiversity conservation in the context of climate change. However, current studies on predictive geographic patterns of plant diversity often fail to separate the effects of global climate change from other influencing factors. In this study, we developed a spatial simulation model of spermatophyte family diversity (SSMSFD) based on data collected from 200 nature reserves covering approximately 1,500,000 km2, where direct anthropogenic disturbances to plant diversity and the surrounding environment are absent. We predicted the spermatophyte family diversity for all provinces in China in 2020, 2040, and 2080, considering the impacts of global climate change. On average, China currently exhibits 118 plant families per 25 km2, with a decreasing trend from southeast to northwest. When considering only the effects of global climate change, excluding direct anthropogenic disturbances, our results indicate that under the Shared Socioeconomic Path Scenarios (SSPs) 245 and 585, spermatophyte family diversity is projected to slowly increase in most Chinese provinces from 2021 to 2080. Notably, the increase is more pronounced under SSPs585 compared to SSPs245. Global climate change has a positive effect on plant diversity, in contrast to the negative impact of anthropogenic disturbances that often lead to declines in plant diversity. This research highlights the contrasting outcomes of future plant diversity under the sole influence of global climate change and the significant negative effects of anthropogenic disturbances on diversity.

20.
Evol Lett ; 8(2): 295-310, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38525032

RESUMO

Little is known about the metabolic basis of life-history trade-offs but lipid stores seem to play a pivotal role. During reproduction, an energetically highly costly process, animals mobilize fat reserves. Conversely, reduced or curtailed reproduction promotes lipid storage in many animals. Systemic signals from the gonad seem to be involved: Caenorhabditis elegans lacking germline stem cells display endocrine changes, have increased fat stores and are long-lived. Similarly, germline-ablated Drosophila melanogaster exhibit major somatic physiological changes, but whether and how germline loss affects lipid metabolism remains largely unclear. Here we show that germline-ablated flies have profoundly altered energy metabolism at the transcriptional level and store excess fat as compared to fertile flies. Germline activity thus constrains or represses fat accumulation, and this effect is conserved between flies and worms. More broadly, our findings confirm that lipids represent a major energetic currency in which costs of reproduction are paid.

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