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Turtle species in the Family Podocnemididae, including the Colombian endemic and critically endangered Magdalena River Turtle Podocnemis lewyana, characteristically present low recapture rates that preclude estimation of population parameters using maximum likelihood modeling. In our 12-year monitoring project with this species, we evaluated changes in relative abundances, proportions of sex/size classes, and individual body sizes and body conditions in a population in four channels in the middle Magdalena River drainage. We also inspected for associations between trends in changes in these variables and differences in hunting pressure and habitat degradation. To inspect for temporal and spatial demographic dynamics, we estimated variation in relative abundances using the Catch Per Unit Effort index, the total number of turtles captured over an entire 5-day sampling period using ten baited funnel traps. Relative abundances and the proportions of sex/size classes were different between sites and years. We found a significant decline in the proportion of females and juveniles over time, along with evidence that the females still present were smaller in body size. Our results support the hypothesis that hunting eliminates adult females from these sites, perhaps also translating into a reduction in recruitment. The lack of evidence of generalized declines in body condition of all size classes suggests that habitat degradation might contribute less to the population declines in this region. Our results also illustrate that even when recapture rates are low, monitoring turtles via standardized trapping may yield insights into the population's conservation status that other relative abundance indices cannot.

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Along the northern Mid-Atlantic Ridge (nMAR), in habitats under moderate (<10 °C) hydrothermal influence on the Snake Pit vent field (SP), large assemblages dominated by Bathymodiolin mussels remain poorly characterised, contrary to those in warmer habitats dominated by gastropods and alvinocaridid shrimps that were recently described. In this study, we assessed and compared the population structure, biomass, diversity and trophic interactions of two Bathymodiolus puteoserpentis assemblages and their associated fauna at SP. Three sampling units distanced by 30 cm were sampled in 2014 during the BICOSE cruise at the top of the Moose site (''Elan'' site), while few meters further down three others, distanced by ∼1 m were obtained in 2018 during the BICOSE 2 cruise at the edifice's base. We observed a micro-scale heterogeneity between these six sampling units partially explained by temperature variations, proximity to hydrothermal fluids and position on the edifice. Meiofauna dominate or co-dominate most of the sampling units, with higher densities at the base of the edifice. In terms of macrofauna, high abundance of Pseudorimula midatlantica gastropods was observed at the top of the vent edifice, while numerous Ophioctenella acies ophiuroids were found at the base. Contrary to what was expected, the apparent health and abundance of mussels seems to indicate a current climax stage of the community. However, the modification of B. puteoserpentis isotopic signatures, low number of juveniles decreasing over the two years and observations made during several French cruises in the study area raise questions about the fate of the B. puteoserpentis population over time, which remains to be verified in a future sampling campaign.

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Protected areas in South Asia face significant challenges due to human disturbance and deforestation. The ongoing debate surrounds the recent surge in illegal encroachment of forest buffer zones in the Musali divisional secretariat division (DSD), which has led to a significant loss of forest cover over the past three decades. In this context, detecting changes in forest cover, assessing forest health, and evaluating environmental quality are crucial for sustainable forest management. As such, our efforts focused on assessing forest cover dynamics, forest health, and environmental conditions in the DSD from 1988 to 2022. We employed standardized image processing techniques, utilizing Landsat-5 (TM) and Landsat-8 (OLI) images. However, the forest area in the DSD has shown minimal changes, and environmental conditions and forest health have illustrated considerable spatial-temporal variations over the 34 years. The results indicated that 8.5 km2 (1.9%) of forest cover in the DSD has been converted to other land use classes. Overall, the Normalized Difference Vegetation Index (NDVI) has declined over time, while Land Surface Temperature (LST) exhibits an increasing trend. The regression results demonstrated a robust inverse relationship between LST and NDVI. The declining vegetation conditions and the increasing LST contribute to an increase in environmental criticality. The derived maps and indices will be beneficial for forest authorities in identifying highly sensitive locations. Additionally, they could enable land use planners to develop sustainable land management strategies.

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The body condition index (BCI) is an indicator of both reproductive success and health in small mammals and might help to understand ecological roles of species. We analyzed BCI data from 28,567 individuals trapped in Lithuania between 1980 and 2023. We compared BCIs between species and examined differences in age groups, gender, and reproductive statuses within each species. Seven out of eighteen species had sample sizes with N < 100. In terms of species, we found that seven of the eight species with the highest average BCIs are granivores or omnivores, which can consume animal-based food at least seasonally. The two contrasting (decreasing or increasing) BCI patterns observed during ontogeny can be related to diet differences among juveniles, subadults, and adult animals. Our results demonstrate that reproductive stress has a negative impact on the BCI of adult females in all analyzed species and nearly all adult males. Although the animals with extremely low BCI consisted mostly of shrews, for the first time we found 23 common and pygmy shrews exhibiting the Chitty effect, i.e., a very high body mass resulting in a BCI > 5.0. This is the first multi-species approach of body condition at middle latitudes. The results increase our understanding of how changing environmental conditions are affecting small mammals.

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Microplastics (MPs) in the aquatic environment pose a serious threat to biota, by being confounded with food. These effects occur in mussels which are filter-feeding organisms. Mussels from the genus Mytilus sp. were used to evaluate the ecotoxicological effects of two MPs, polypropylene (PP) and polyethylene terephthalate (PET), after 4 and 28-days. Measured individual endpoints were condition index and feeding rate; and sub-individual parameters, metabolism of phase I (CYP1A1, CYP1A2 and CYP3A4) and II (glutathione S-transferases - GSTs), and antioxidant defense (catalase - CAT). MPs decreased both condition index (CI) and feeding rate (FR). No alterations occurred in metabolic enzymes, suggesting that these MPs are not metabolized by these pathways. Furthermore, lack of alterations in GSTs and CAT activities suggests the absence of conjugation and oxidative stress. Overall, biochemical markers were not responsive, but non-enzymatic responses showed deleterious effects caused by these MPs, which may be of high ecological importance.

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The current study aimed to describe the annual gametogenic phenology of the oyster Magallana bilineata (Röding, 1798) (=Crassostrea madrasensis), which is found on the west coast of Moheshkhali Island, Cox's Bazar, Bangladesh. Samples were drawn monthly from the intertidal region during low tide, from which 20 adult individuals were selected at random for biometry and histology. The mean condition index (CI), a ratio of tissue wet weight (g) to shell length (cm), varied from 0.58 ± 0.08 to 1.32 ± 0.36. Histology revealed two spawning cycles in the habitat of M. bilineata over the 12 months of the study. Gametogenesis initiated in December and May, and ripe animals principally occurred from July to September and February to May. In the habitat, M.bilineata exhibited two spawning peak periods: April to June and August to October. The undifferentiated stage as a preparatory step for the next spawning extended from November to February for the first spawning cycle and for a brief period in June for the next spawning cycle. The initiation of spawning in March could be associated with the high-level decline of salinity and increased temperature between February and March, in association with the annual rainfall start, whereas the next spawning cycle could be associated with a gradual increase in salinity. No spawning activity was reported from December to February, when the water temperature remained below 22 °C. Further study could be undertaken on the timing of spatfall of M.bilineata in the habitat to harvest spats for commercial farming of this promising species.

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The degradation of road pavements due to environmental factors is a pressing issue in infrastructure maintenance, necessitating precise identification of pavement distresses. The pavement condition index (PCI) serves as a critical metric for evaluating pavement conditions, essential for effective budget allocation and performance tracking. Traditional manual PCI assessment methods are limited by labor intensity, subjectivity, and susceptibility to human error. Addressing these challenges, this paper presents a novel, end-to-end automated method for PCI calculation, integrating deep learning and image processing technologies. The first stage employs a deep learning algorithm for accurate detection of pavement cracks, followed by the application of a segmentation-based skeleton algorithm in image processing to estimate crack width precisely. This integrated approach enhances the assessment process, providing a more comprehensive evaluation of pavement integrity. The validation results demonstrate a 95% accuracy in crack detection and 90% accuracy in crack width estimation. Leveraging these results, the automated PCI rating is achieved, aligned with standards, showcasing significant improvements in the efficiency and reliability of PCI evaluations. This method offers advancements in pavement maintenance strategies and potential applications in broader road infrastructure management.

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Future climate change scenarios project that the increase in surface temperatures will affect ocean temperatures, inducing shifts in marine biodiversity. Sea turtles are species that are particularly vulnerable to the effects of climate change because temperature is a factor that influences embryonic development. We collected clutches of olive ridley turtles from a mass-nesting beach in the Mexican Pacific, which were incubated in ex situ conditions. When the hatchlings emerged, we measured the body condition index-which evaluates the weight-length relationship-and swim thrust, both were considered traits associated with fitness, termed "fitness proxies," and evaluated the effects of incubation temperature, maternal effects, and paternity on these fitness proxies. The body condition index was correlated positively and significantly with the arribada month and temperature during the last third of the incubation period but showed an inverse relationship with the maternal effect. While swim thrust was positively correlated with the maternal effect and the arribada month, there was an inverse relationship with incubation temperature during the first third of the period. Paternity, whether single or multiple, did not have a significant effect on either fitness proxies; however, it may have effects on the average fitness of a population of hatchlings. These results underscore the need to expand research on the sublethal effects of high incubation temperatures on the adaptation and survival of sea turtles, particularly in scenarios of rapid climate change.

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This study investigated the effect of heavy metals on the pearl oyster Pinctada radiata from 5 sites along the coast of Alexandria, with focus on its ecological health and potential risks to human consumption. Pollution results showed that Abu-Qir had the highest Cu and Cd values. Montaza and Eastern Harbor had the highest Fe and Pb values, respectively. Statistically, differences in metal concentrations among study sites were significant (p < 0.05). Non-carcinogenic risk (TTHQ) of tested metals and carcinogenic ones of Cd and Pb showed "high risk" on human health by consuming pearl oysters. Morphometric measurements and condition indices were studied to assess growth patterns and health in relation to heavy metals exposure. Key findings showed detectable declines in size and condition index in Eastern Harbor, whereas Abu-Qir recorded the highest values. This condition index performance presented Abu-Qir, Mammora, and Miami as ideal locations for spat collection and oyster rearing, potentially enhancing Egyptian pearl farming. Average values of spatial proximate contents of pearl oyster showed that it was rich in proteins (33.07-58.52%) with low fat content (1.39-1.87%) and carbohydrates (9.72-17.63%). Biochemical composition of pearl oyster demonstrated its high nutritional value which supported its promotion as a functional food for human consumption. The calorie content of pearl oyster was less than 2 Kcal, making this species an alternative source of healthy food to reduce obesity. Regression analysis indicated that Cu, Cd, and Pb had significant effect on 2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity, calories, vitamins, and pigment content of the collected oysters.

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The increased use of hexavalent chromium (Cr6+) in various industrial applications has contributed to its elevated levels in the environment, especially the aquatic environment. Thus, there is the potential for accumulation of Cr6+ in the tissues of aquatic organisms and consequent toxic effects. The toxic effects of Cr6+ in aquatic organisms have been widely reported; however, little is known about the patterns of tissue accumulation of Cr6+ and its toxicity in aquatic mollusks. Thus, the present study investigated the effects of Cr6+ exposure on the tissue distribution, proximate composition, and histopathology of an aquatic mollusk, periwinkle (Littorina littorea). The animals were exposed to sublethal concentrations of Cr6+ (0.42, 0.84, and 4.2 mg/L) for 30 days, after which the condition index, tissue accumulation, proximate composition, and histopathological effects were determined. The control animals were maintained in a medium that did not contain Cr6+ (0 mg/L). The condition index did not differ significantly among the groups. The levels of Cr6+ in the tissues differed significantly among the different tissue types while there was no significant effect of the exposure concentration, except in the foot tissue. The proximate parameters (protein, carbohydrates, lipid, crude fiber, and moisture contents) differed significantly among the groups. The protein contents of the exposed animals were significantly lower than those of the control animals and the histological architecture of the major organs was altered in the chromium-exposed animals. The findings from this study indicate a low potential of L. littorea to bioaccumulate Cr6+ in its tissues at the low exposure concentrations tested in this study; as such, its consumption may not pose any serious health risks to humans. However, changes in the proximate composition and histological architecture of the exposed L. littorea show that Cr6+ is potentially toxic to periwinkles.

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As financial conditions become more complex and variable, capturing economic patterns becomes harder. The Financial Conditions Index (FCI) has gained traction as a tool to assess the performance of financial markets in nations or regions. This paragraph has created the China FCI using various financial indicators from 2002 to 2022. And with the use of statistical models like DMA-TVP-FAVAR, mixed-frequency Granger causality test, TVP-SV-VAR, and MS-VAR to analyze the relationship between China's financial condition, real economy, and the crude oil market. Different impacts were observed over time and in response to economic shocks, Results show that the fluctuation of international oil price has a negative impact on our financial condition. Therefore, the government should consider the impact of external shock factors such as international crude oil price when formulating financial policies to prevent financial risks.

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Mytilus galloprovincialis is common in Morocco's Anza-Taghazout coast, previously polluted by wastewater. Since treatment plants were installed in 2016, no study examined the mussels' reproduction. Our study assessed how wastewater treatment affects the reproduction and growth of the M. galloprovincialis mussel on Moroccan coasts, particularly in the Anza-Taghazout area. We aimed to clarify the impacts of treated effluents on this vital invertebrate. This research explored their reproductive parameters, with samples taken from 2017 to 2018 at Anza, Aourir, and Imouran. Results show all gametic stages with three spawning periods. The gonadal index exceeds 1.4 at all sites, indicating a short resting phase. The sex ratio is balanced in Aourir and Imouran, but Anza has more males. The length-weight relationship showed the b value of 1.56 (R2 = 0.32); 1.71 (R2 = 0.35), and 1.70 (R2 = 0.26) for Anza, Aourir, and Imouran respectively. This suggests a slight negative allometric relationship. The condition index showed a progressive trend, and M. galloprovincialis improved due to enhanced environmental quality after treatment.

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BACKGROUND: Most aquatic biota's reproductive biology and life cycle are essential to the sustainable management and development of coastal ecosystems and aquaculture. The bivalve Paphia textile (Gmelin 1791), also known as Paratapes textilis, has an economic value in Indo-Pacific waters, including the Red Sea and the Suez Canal lakes, the Egyptian coasts. However, P. textile suffers from extensive fishing and exploitation. AIM: The present work aims to study the Paphia textile's reproductive cycle on the Egyptian coasts of the Red Sea for the first time. It helps to manage and develop the coastal ecosystems and aquaculture. METHODOLOGY: Samples were collected monthly from two saline lakes in the Suez Gulf from December 2019 to November 2020. As part of the comprehensive research study, sex ratio, condition index, sexuality, histological analysis of gonads, shell size, and gonad index were used to investigate the reproductive cycle. RESULTS: The results reveal a male-biased sex ratio, possibly due to anthropogenic stressors. The Paphia textile is dioecious. No hermaphrodite cases were observed in the studied specimens. The condition index in winter and spring indicates periods dominated by mature individuals. Five reproductive maturity stages were assigned for both P. textile males and females. Due to the simultaneous development of several developmental stages monthly throughout the sampling year, warm water may be responsible for non-sequential gametogenic cycles. As measured environmental parameters correlate with maturity stages, temperature, salinity, and chlorophyll a play important role in gonad growth. The size at first sexual maturity at which 50% of the Paphia textile population reached maturity ranged from 28.60 to 31.50 mm for females, and between 31.70 and 34.10 mm for males. As the gonad index increases during the ripe stages, this index decreases during the resting, spawning, and spent phases. CONCLUSIONS: The findings suggest the most suitable temperature for aquaculture spawning is between 20 °C and 30 °C in subtropical waters. Fishing should generally be prohibited at sizes less than 28.60 mm for better management and sustainability of this valuable aquatic resource on the Egyptian coasts of the Red Sea.

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Body condition indices and related metrics can help assess habitat quality and other ecological processes, and ideally, these metrics are based on measures of lipids directly extracted from the species of interest. In recent decades, barred owls (Strix varia) have become a species of conservation concern as they invaded older forests of the US Pacific Northwest, and caused population declines of the closely related and federally threatened northern spotted owl (Strix occidentalis caurina). A simple and effective measure of barred owl body condition could help to understand how habitat quality varies within their new range, which in turn can inform their management and other aspects of their ecology. Using 77 barred owl carcasses collected during experimental removals in Washington and Oregon, USA, we measured the amount of lipid in each specimen with proximate body composition analysis. We then fit and compared (with adjusted R2 values) alternative linear regression models to estimate the percent lipids in dry mass of the owls based on morphometric body condition indices, a qualitative fat score of subcutaneous breast fat, sex and the time of year females were collected (relative to egg production). Adjusted R2 values for all models ranged from 0.49 to 0.87, with the best model including mass divided by foot-pad length, fat score, sex and the time of year a female was collected. Most models generated comparable estimates of percent lipids at a population level and we provided correction factors to apply these models when used with live barred owls, allowing for site-specific comparisons of body condition among individuals inhabiting a diversity of environmental conditions.

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Investigations of winter diets and foraging in fish are rare, and less so for migratory species in the temperate zone. In the Great Lakes, the round goby (Neogobius melanostomus) is known to out-migrate from nearshore habitats to offshore depths in the winter months. However, in Great Lake tributaries, populations of this fish were found up to 25 km upstream during winter months. Distance upstream was a predictor of out-migration behavior with populations farthest upstream remaining as winter residents, whereas populations nearest the lakes out-migrated. Distance inland was also a predictor of fish total length, but not Fulton's condition index. Seasonal resources and local prey availability shaped the diets of these fish, but resource use remained unchanged over time since invasion. Total length and body condition also remained unchanged over time since the invasion. Plasticity in both diet and migration behavior seems to be beneficial traits for the inland invasion success of this fish.

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A correct understanding of the pavement performance change law forms the premise of the scientific formulation of maintenance decisions. This paper aims to develop a predictive model taking into account the costs of different types of maintenance works that reflects the continuous true usage performance of the pavement. The model proposed in this study was trained on a dataset containing five-year maintenance work data on urban roads in Beijing with pavement performance indicators for the corresponding years. The same roads were matched and combined to obtain a set of sequences of pavement performance changes with the features of the current year; with the recurrent-neural-network-based long short-term memory (LSTM) network and gate recurrent unit (GRU) network, the prediction accuracy of highway pavement performance on the test set was significantly increased. The prediction result indicates that the generalization ability of the improved recurrent neural network model is satisfactory, with the R2 achieving 0.936, and of the two models the GRU model is more efficient, with an accuracy that reaches almost the same level as LSTM but with the training convergence time reduced to 25 s. This study demonstrates that data generated by the work of maintenance units can be used effectively in the prediction of pavement performance. This article is part of the theme issue 'Artificial intelligence in failure analysis of transportation infrastructure and materials'.

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A total of 30 samples of Atlantic bluefin tuna were analysed for total mercury concentration. Relationships between total mercury content and age, Fulton's condition index (K) and fat content were statistically evaluated. The effect of muscle status (raw, pre-canning, canned) on mercury content was also investigated. The average total mercury content was: 1.185 ± 0.662 mg/kg in raw, 1.481 ± 0.893 mg/kg in pre-canning and 1.393 ± 0.882 mg/kg in canned samples, respectively. Canning promotes a statistically significant increase in the concentration of mercury. The weight of fish, K and fat content are useful tools to estimate the mercury accumulation in Atlantic bluefin tuna. The results of the present study represent a contribution to the assessment of the EU mercury levels in Atlantic bluefin tuna.

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Drought has major consequences for agricultural activity, economy, and the environment. For improved drought management, it is necessary to assess drought severity, frequency, and the potential of drought occurrence. The purpose of this study is to use drought indices, standardized precipitation index (SPI), and vegetation condition index (VCI) to characterize the severity of drought and investigate the association between drought severity and subjective well-being among local farmers. The SPI was used to quantify precipitation deficits at various time scales, while the VCI was utilized to monitor crop and vegetation drought conditions. Throughout the period 2000-2017, satellite data were incorporated, as well as a household survey of rice farmers in the dry zone research region in northeastern Thailand. The findings suggest that extreme droughts occur more frequently in the central part of the northeastern region of Thailand than in the rest of the region. The influence of drought on farmers' wellbeing was evaluated at various drought severity levels. Drought and overall wellbeing are strongly linked at the household level. Thai farmers in drought-prone areas are dissatisfied with their livelihoods more than farmers in less-affected area. It is intriguing that farmers who live in drought-prone areas are more content with their lives, their communities, and their occupations than farmers who live in less drought-prone areas. In this context, using proper drought indices could potentially improve the utility of governmental interventions and community-based programs targeted at assisting drought-affected people.

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The entire shellfish farming sector is negatively affected by heat waves. Predictive models show that while heat waves are not predicted to exceed 28 °C in the northern Adriatic Sea over the coming decades, their duration will increase to periods of up to 30 days. Knowledge regarding the effects of heat waves on bivalves at physiological and molecular level is still limited. This study attempted to simulate what will happen in the future in Pacific oysters exposed to prolonged heat waves, assessing morphometric and physiological indices, and investigating the expression level of a number of genes, including the chaperone heat shock proteins HSP70, HSP72 and HSP90, and the factor P53. A state of stress in the heat wave-exposed animals was found, with loss of body weight and energy resources: despite showing a higher clearance rate, these animals were unable to absorb the nutrients required to maintain homeostasis, as well as demonstrating an alteration in hemolymphatic AST activity, total calcium and magnesium concentration. mRNA levels of all examined genes increased in response to thermal stress, with long-term overexpression, activating cell stress defense mechanisms and modulating the cycle cell. The results of this study indicate that heat waves affect oyster welfare, with consequences for the productivity of the sector due to the lack of salable products.

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In this work, we calculated the body condition indices, K-Fulton and scaled mass index (SMI), of reproductive and non-reproductive Caiman latirostris adult females as an indication of stored energy. We considered 87 adult females captured from 2001 to 2018, both reproductive and non-reproductive. The body condition was calculated considering two scenarios: (a) only the weight of the female, and (b) the sum of the weight of the female and the average dry weight of her nest. We tested the difference in body condition between reproductive and non-reproductive females. We also evaluated the minimal body condition required to guarantee that females above it are reproductive by drawing a line that separated the body condition of strictly reproductive individuals from those that may or may not be reproductive. Reproductive females had better body condition than non-reproductive ones. Our SMI.S line separated almost 70% of the reproductive females. Based on our results, we can guarantee that a female whose body condition is above the line will reproduce, although not all those females below the line are non-reproductive, as a few of those under the line will nest. With this information, we have one more biological indicator to take into account when making management and conservation decisions.