Hasil untuk "Natural history (General)"

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DOAJ Open Access 2025
Effect of reduced osmolality in glucose-based extenders on the post-thaw motility of Mediterranean brown trout (Salmo cettii) spermatozoa

Aleksandra Krasilnikova, Michele Di Iorio, Emanuele Antenucci et al.

The current study aimed to compare the effects of decreasing osmolality in glucose-based extenders containing methanol alone versus a methanol-ethylene glycol combination on the post-thaw motility of Mediterranean brown trout (Salmo cettii) spermatozoa. Milt was collected from mature males in the Biferno River, Southern Italy, and cryopreserved using a control cryomedium (150 mM glucose with 7.5% methanol) and experimental variants with reduced glucose (100 mM, 50 mM) paired with methanol alone or combined with 2.5% ethylene glycol. Samples were cryopreserved in 0.25 mL straws with a final sperm concentration of 3.0 × 109 spermatozoa/mL, corresponding to 750 × 106 spermatozoa/straw. Sperm motility and kinematic parameters of Mediterranean brown trout were assessed for fresh sperm and post-thaw samples cryopreserved in various cryomedia. Fresh sperm exhibited robust motility (89.0 ± 8.4%) and curvilinear velocity (VCL, 121.2 ± 22.4 µm/s), while the control cryomedium preserved motility at 65.9 ± 12.9% and VCL at 117.6 ± 26.1 µm/s; the experimental 100 mM glucose with 7.5% methanol and 2.5% ethylene glycol treatment yielded comparable motility (65.6 ± 11.6%) but reduced VCL (81.5 ± 16.1 µm/s, p < 0.05). Other treatments showed diminished efficacy, particularly at 50 mM glucose. These findings reveal that a hypotonic extender with methanol-ethylene glycol synergy sustains motility after cryopreservation despite lower glucose levels, demonstrating that the osmotic threshold of extender can be lowered to 100 mOsm/kg without compromising salmonid sperm function. This approach offers a practical tool for conserving S. cettii, supporting broader restoration efforts amid escalating environmental pressures.

Science, General. Including nature conservation, geographical distribution
DOAJ Open Access 2025
Environmental preferences of green sea turtles (Chelonia mydas) for egg-laying on a fringing reef pocket beach, Mayotte Island

Sophie Morisseau, Sophie Morisseau, Matthieu Jeanson et al.

Understanding the spatial ecology of sea turtles is essential to ensure their long-term conservation by the preservation of their environment. The distribution and environmental preferences for egg-laying by the green turtle (Chelonia mydas) were studied on Grande Saziley beach in Mayotte (north of the Mozambique Channel). Green turtle nesting activity was geolocated during night patrols and the depth of specific nests was measured during two field campaigns in 2021 and 2022. Various original environmental parameters related to vegetation and beach morphology were extracted in a GIS environment based on this geolocated data using orthophotography and digital elevation models (DEMs) created by drones prior to field deployments. Sediment samples were also collected from the beach. Thanks to the combination of fieldwork and GIS analysis, this study makes it possible to examine a set of variables, which until now have rarely been studied simultaneously. The results showed that the Grande Saziley beach is a heterogeneous site with the distribution of egg-laying being concentrated in two hotspots. After principal component and GLMM statistical analysis, it appeared that gravid females preferentially lay in a low proportion of coarse sand at the bottom of the nest, at higher elevation and predominantly in surface sand with a low calcium carbonate content. This preference seems to be linked more to elevation, where black sand is mainly found at the top of the beach, rather than an intentional choice based on sand composition. No significant egg-laying site-related variables were found to explain the variations in nest depth. Our study was based on a new approach combining GIS techniques and drone surveys, enabling the collection of environmental parameters, a methodology that can easily be reproduced on other nesting beaches, reducing field workload. However, this work should be continued to assess the viability of sites for clutch survival while considering the spatial and temporal heterogeneity of the environment.

Science, General. Including nature conservation, geographical distribution
arXiv Open Access 2025
Utilizing Sequential Information of General Lab-test Results and Diagnoses History for Differential Diagnosis of Dementia

Yizong Xing, Dhita Putri Pratama, Yuke Wang et al.

Early diagnosis of Alzheimer's Disease (AD) faces multiple data-related challenges, including high variability in patient data, limited access to specialized diagnostic tests, and overreliance on single-type indicators. These challenges are exacerbated by the progressive nature of AD, where subtle pathophysiological changes often precede clinical symptoms by decades. To address these limitations, this study proposes a novel approach that takes advantage of routinely collected general laboratory test histories for the early detection and differential diagnosis of AD. By modeling lab test sequences as "sentences", we apply word embedding techniques to capture latent relationships between tests and employ deep time series models, including long-short-term memory (LSTM) and Transformer networks, to model temporal patterns in patient records. Experimental results demonstrate that our approach improves diagnostic accuracy and enables scalable and costeffective AD screening in diverse clinical settings.

en q-bio.QM, cs.LG
arXiv Open Access 2024
IBCB: Efficient Inverse Batched Contextual Bandit for Behavioral Evolution History

Yi Xu, Weiran Shen, Xiao Zhang et al.

Traditional imitation learning focuses on modeling the behavioral mechanisms of experts, which requires a large amount of interaction history generated by some fixed expert. However, in many streaming applications, such as streaming recommender systems, online decision-makers typically engage in online learning during the decision-making process, meaning that the interaction history generated by online decision-makers includes their behavioral evolution from novice expert to experienced expert. This poses a new challenge for existing imitation learning approaches that can only utilize data from experienced experts. To address this issue, this paper proposes an inverse batched contextual bandit (IBCB) framework that can efficiently perform estimations of environment reward parameters and learned policy based on the expert's behavioral evolution history. Specifically, IBCB formulates the inverse problem into a simple quadratic programming problem by utilizing the behavioral evolution history of the batched contextual bandit with inaccessible rewards. We demonstrate that IBCB is a unified framework for both deterministic and randomized bandit policies. The experimental results indicate that IBCB outperforms several existing imitation learning algorithms on synthetic and real-world data and significantly reduces running time. Additionally, empirical analyses reveal that IBCB exhibits better out-of-distribution generalization and is highly effective in learning the bandit policy from the interaction history of novice experts.

en cs.LG
DOAJ Open Access 2023
Increasing coastal reclamation by Invasive alien plants and coastal armoring threatens the ecological sustainability of coastal wetlands

Jian Li, Jian Li, Zhanrui Leng et al.

Coastal reclamation is becoming a common land restoration trend all over the world as a result of the rising demand for land. Though restoring coastal wetlands has significant economic advantages, a slew of adverse ecological effects threatens the carbon functions of coastal wetlands. For the objective of making appropriate land use policymaking, the ecological-economic trade-offs of reclamation initiatives must be carefully considered. In this study, we utilized appropriate models to estimate the ecosystem service values and economic benefits of invasive alien plants and embankment seawall coastal reclamation in China. We centered on three main ecology-related ecosystem services: greenhouse gas regulation, storm-flood-erosion control, and waste treatment/habitat preservation. Coastal reclamation intensity index and financial analysis were utilized to assess the trade-offs between ecological degradation and economic benefit resulting from land reclamation. Findings reveal that a total of 26,322 ha and 10,731 km of coastal wetlands were reclaimed by Spartina alterniflora and seawalls respectively from 2000 to 2020 in China. S. alterniflora reclamation resulted in a significant decline of ESV loss of 5,702,454 Yuan ha−1, while seawalls reclamation yielded some Ecosystem service value (ESV) gain of 4,800, 111 Yuan km-1 from 2000-2020. The combined effects of coastal armoring and invasive S. alterniflora reclamation led to a loss of about 32.2 billion Yuan in ESV for the study duration. Economic gains failed to make up for the ecosystem service value ESV loss, since the cumulative ESV loss significantly exceeded the economic gains across the period studied. This correlation of trade-offs emerged from reclamation development that favored quick economic gains over long-lasting ecological value, posing a potential long-term threat to the ecological integrity and carbon sinks in coastal wetlands. To establish an equilibrium between seawall reclamation and Invasive alien plant species spread in coastal wetlands, stakeholders could use this scientific knowledge as leverage to avert future irreparable losses.

Science, General. Including nature conservation, geographical distribution
DOAJ Open Access 2023
Navigating power in conservation

Ross T. Shackleton, Gretchen Walters, Jevgeniy Bluwstein et al.

Abstract Conservation research and practice are increasingly engaging with people and drawing on social sciences to improve environmental governance. In doing so, conservation engages with power in many ways, often implicitly. Conservation scientists and practitioners exercise power when dealing with species, people and the environment, and increasingly they are trying to address power relations to ensure effective conservation outcomes (guiding decision‐making, understanding conflict, ensuring just policy and management outcomes). However, engagement with power in conservation is often limited or misguided. To address challenges associated with power in conservation, we introduce the four dominant approaches to analyzing power to conservation scientists and practitioners who are less familiar with social theories of power. These include actor‐centered, institutional, structural, and, discursive/governmental power. To complement these more common framings of power, we also discuss further approaches, notably non‐human and Indigenous perspectives. We illustrate how power operates at different scales and in different contexts, and provide six guiding principles for better consideration of power in conservation research and practice. These include: (1) considering scales and spaces in decision‐making, (2) clarifying underlying values and assumptions of actions, (3) recognizing conflicts as manifestations of power dynamics, (4) analyzing who wins and loses in conservation, (5) accounting for power relations in participatory schemes, and, (6) assessing the right to intervene and the consequences of interventions. We hope that a deeper engagement with social theories of power can make conservation and environmental management more effective and just while also improving transdisciplinary research and practice.

Ecology, General. Including nature conservation, geographical distribution
DOAJ Open Access 2023
A conservation planning strategy applied to the evolutionary history of the mantellid frogs of Madagascar

Miguel R. Ferreira, Francesco Belluardo, Walter Cocca et al.

Abstract Phylogenetic diversity is an increasingly applied metric used to maximize the representation of evolutionary history in spatial conservation planning. When following this approach, researchers commonly overlook sites with a relatively higher proportion of recently diverged endemic species, also known as centers of neo-endemism. Here we aim to demonstrate how targeting the conservation of different facets of diversity (taxonomic diversity, phylogenetic diversity and centers of endemism) can provide more cost-effective solutions to the conservation of the all evolutionary spectrum of biodiversity. We do so by using the mantellid frogs of Madagascar as a case study. Our results confirm that areas with high concentrations of neo-endemism can be effectively identified as conservation planning priorities only if we specifically target them. Neglecting areas that are poor in phylogenetic diversity may therefore compromise the maintenance of diversification processes, particularly when lesser proportions of the landscape are protected. This approach can be of particular interest to island ecosystems, since they often harbor unique and restricted evolutionary radiations.

General. Including nature conservation, geographical distribution
DOAJ Open Access 2023
Differential activation of neuropeptide FF receptors by gonadotropin-inhibitory hormone peptides in the European sea bass

Bin Wang, Bin Wang, Bin Wang et al.

Neuropeptide FF (NPFF) and gonadotropin-inhibitory hormone (GnIH) are thought to be paralogous, and a recent study has revealed that both NPFF and GnIH peptides can activate the GnIH receptor (GnIHR, also called NPFFR1) in the European sea bass (Dicentrarchus labrax). However, whether GnIH can bind to the NPFF receptor (NPFFR2) is still yet unknown in this species. Accordingly, we further investigated the potential interactions between GnIH and NPFFR2 (two NPFFR2 forms present in sea bass, namely NPFFR2-1 and NPFFR2-2) on the intracellular signaling pathways. Neither GnIH1 nor GnIH2 had any effect on basal CRE-luc activity, while forskolin-stimulated CRE-luc activity was significantly reduced when COS-7 cells expressing sea bass NPFFR2-1 and NPFFR2-2 were challenged with these two GnIH peptides. NPFF and NPAF also inhibited forskolin-induced CRE-luc activity via their cognate receptors. An evident stimulation of SRE-luc activity was observed when COS-7 cells transfected with NPFFR2-1 and NPFFR2-2 were treated with NPFF and NPAF, whereas GnIH peptides had no effect, except a slight but significant increase elicited by 1000 nM of GnIH1 in COS-7 cells expressing NPFFR2-2. Moreover, only GnIH2 exerted an inhibitory action on NFAT-RE-luc activity in COS-7 cells expressing NPFFR2-1. None of GnIH or NPFF peptides altered ERK phosphorylation levels via NPFFR2 receptors. Our results provide new evidence that sea bass GnIH peptides may exert their functions partially via NPFFR2, and PKA, PKC and Ca2+ routes are potential mediators.

Science, General. Including nature conservation, geographical distribution
DOAJ Open Access 2023
Microbe-mineral interactions in the Plastisphere: Coastal biogeochemistry and consequences for degradation of plastics

Maya S. Dodhia, Kelsey L. Rogers, Victor Fernández-Juárez et al.

Microbe-mineral interactions, such as mineral substrate utilization and aggregate formation, have played a key role in the cycling of elements through Earth evolution. In water, soils, and sediment biogeochemistry modulates microbial community composition and mineral formation over spatial and temporal scales. Plastic is a new material that is now widespread in the environment. Both microbial and mineral associations with plastic comprise the Plastisphere, which influences the fate of plastic. This study focuses on how the biogeochemical environment defines microbial and mineral association with polyethylene (PE) and polystyrene (PS) over a 12-month period in a temperate coastal harbor. The coastal harbor environment was separated into 3 conceptual compartments defined by physical and biogeochemical conditions, that allow transfer of electrons between species e.g., light penetration and redox setting. Microbe and mineral association were investigated in the water column, top sediment, and bottom sediment by applying a range of modern analytical techniques to identify changes in the chemical structures of plastics, microbial community development, metal, salt and mineral formation. The epiplastic microbial community was distinct to that of the surrounding environment across changing redox conditions. The type and oxidation state of metallic minerals formed on plastics or entrapped in the biofilm matrix related to the dominant abiotic and biotic processes across redox conditions. FTIR spectroscopy indicated the occurrence of PE and PS oxidation in the various biogeochemical environments. Combined, these findings demonstrate that redox conditions and surrounding biogeochemistry mediate the composition of mineralogical and biological loading of PE and PS in coastal marine environments. This suggests that the biogeochemical setting in which the plastics are stored constrains the development of plastic interfacial biogeochemistry and the potential for plastic degradation and transport over time.

Science, General. Including nature conservation, geographical distribution
arXiv Open Access 2023
Perceived Trustworthiness of Natural Language Generators

Beatriz Cabrero-Daniel, Andrea Sanagustín Cabrero

Natural Language Generation tools, such as chatbots that can generate human-like conversational text, are becoming more common both for personal and professional use. However, there are concerns about their trustworthiness and ethical implications. The paper addresses the problem of understanding how different users (e.g., linguists, engineers) perceive and adopt these tools and their perception of machine-generated text quality. It also discusses the perceived advantages and limitations of Natural Language Generation tools, as well as users' beliefs on governance strategies. The main findings of this study include the impact of users' field and level of expertise on the perceived trust and adoption of Natural Language Generation tools, the users' assessment of the accuracy, fluency, and potential biases of machine-generated text in comparison to human-written text, and an analysis of the advantages and ethical risks associated with these tools as identified by the participants. Moreover, this paper discusses the potential implications of these findings for enhancing the AI development process. The paper sheds light on how different user characteristics shape their beliefs on the quality and overall trustworthiness of machine-generated text. Furthermore, it examines the benefits and risks of these tools from the perspectives of different users.

en cs.HC, cs.AI
DOAJ Open Access 2022
Recreating the Network of Early Modern Natural Philosophy: A Mono- and Multilingual Text Data Vectorization Method

Andrea Sangiacomo, Raluca Tanasescu, Hugo Hogenbirk et al.

How could one create a network representation of a book corpus which spans over two hundred years ? In this paper, we present a method based on text data vectorization for a complex and multifaceted network representation of an early modern corpus of 239 natural philosophy textbooks published in Latin, French, and English. We use unsupervised methods (namely, topic modeling, term frequency – inverse document frequency, and multilingual word embeddings) to represent the broader features of this corpus, such as its homogeneity in style and linguistic usages, both among works written in the same language, and across multiple languages. We call this the ‘textual dimension.’ We also use a collocate analysis of specific keywords to explore how certain concepts were understood, reshaped, and disseminated in the corpus. We call this the ‘semantic dimension.’ Each of these two dimensions provides a different way of correlating the books via text data vectorization and of representing them as a network. Since these dimensions are complex and multifaceted, the network we construct for each of them is a multiplex, made from several layer-graphs. Furthermore, using existing bio-bibliographical information, this research provides the grounds for further expanding the described network representation in such a way as to create a third multiplex, one that explores some of the social features of the authors in question.

History (General)
DOAJ Open Access 2022
Characterizing the oral and distal gut microbiota of the threatened southern sea otter (Enhydra lutris nereis) to enhance conservation practice

Natasha K. Dudek, Alexandra D. Switzer, Elizabeth K. Costello et al.

Abstract The southern sea otter (Enhydra lutris nereis) is a threatened sub‐species in coastal ecosystems. To understand better the role of diet, monitor health, and enhance management of this and other marine mammal species, we characterized the oral (gingival) and distal gut (rectal and fecal) microbiota of 158 wild southern sea otters living off the coast of central California, USA, and 12 captive sea otters, some of which were included in a diet shift experiment. We found that the sea otter fecal microbiota was distinct from that of three other otter species, and that captivity does not significantly alter the community structure of the sea otter gingival or distal gut microbiota. Metagenomic analysis unexpectedly revealed that the majority of sea otter fecal DNA is derived from prey, rather than from indigenous bacteria or host cells as with most other mammals. We speculate that a reduced bacterial biomass in the sea otter gut reflects rapid gut transit time and a particular strategy for foraging and energy harvest. This study establishes a reference for the healthy sea otter microbiota, highlights how a marine lifestyle may shape the mammalian microbiota, and may inform future health assessments and conservation management of sea otter populations.

Ecology, General. Including nature conservation, geographical distribution
DOAJ Open Access 2022
OECMs in marine capture fisheries: Key implementation issues of governance, management, and biodiversity

Serge Michel Garcia, Jake Rice, Jake Rice et al.

The ‘Other Effective Area-based Conservation Measure’ (OECM) concept was first introduced in 2010, by the Conference of the Parties of the Convention on Biological Diversity (CBD COP) in the CBD Strategic Plan for Biodiversity conservation 2011–2020. The concept acknowledged that a range of spatial measures other than protected areas were appropriate for reaching Aichi Target 11 spatial conservation coverage. The OECM definition was adopted in 2018 in CBD COP Decision 14/8, which calls on States to mainstream OECMs into economic sectors, to recognize the current biodiversity conservation benefits and co-benefits from their area-based management measures and enhance them as much as possible. In the marine capture fisheries sector, the identification of OECMs is a work in progress and the issues addressed in this paper are key implementation issues that States and fisheries authorities are or will be encountering regarding their governance, management, and biodiversity outcomes. The purpose of the paper is to draw attention to some key OECM implementation issues arising in marine capture fisheries and to suggest possible approaches to address them. The governance issues addressed relate to enabling frameworks, industrial fisheries, legitimate authorities, long-term commitments, cross-sectoral coordination and planning, and contribution to the Post-2020 Global Biodiversity Framework of the CBD. The management issues considered relate to effectiveness in achieving expected outcomes, costs and benefits of OECMs, spatial relations between OECMs and fisheries, and the role of OECMs in the Ecosystem Approach to Fisheries (EAF). Regarding the significant positive biodiversity outcomes expected from OECMs, issues relate to the type of outcomes expected, their current or intended nature, the level of evidence required, and their relationship to area-based conservation standards.

Science, General. Including nature conservation, geographical distribution
CrossRef Open Access 2021
The Personal Ambitions of a National Hero

Adam Williamson

Abstract: The purpose of this essay was to put the Scottish king and war hero, Robert the Bruce on trial based on the model of the Ted-Ed miniseries ‘History on Trial’. The overarching argument is explored through a dialogue between the prosecutor and defendant of Robert and centres on how Robert Bruce should be remembered; either a Scottish nobleman fueled by personal ambition or a good, strong-willed king who did what was best for his kingdom and people. Both sides present evidence surrounding Bruce’s dedication to his personal ambition to becoming king which included murder and is contrasted by the clemency he should to his rivals/enemies upon becoming king. This leads to a critical approach on the nature of Robert’s loyalty during the early period of Scottish War for Independence and his later uncompromising drive to see Scotland become independent. The nature of how Robert achieved independence is also brought under scrutiny with the suffering he brought to the English and Irish populations. Concluding remarks on Robert’s verdict express the difficult nature of how to accurately remember national heroes and in ensuring a balance between the good and bad sides of them.

DOAJ Open Access 2021
Co-occurrence in ant primary parasitoids: a Camponotus rectangularis colony as host of two eucharitid wasp genera

Gabriela Pérez-Lachaud, Jean-Paul Lachaud

Different assemblages of parasitoids may attack a given host species and non-random distribution patterns in parasitoid species assemblages have been reported on various occasions, resulting in co-occurrence at the population, colony, or even individual host levels. This is the case for different closely related species of eucharitid wasps (a family of specialized ant parasitoids) sharing similar niches and co-occurring on the same host at different levels. Here we reviewed all known associations between eucharitid wasps and the ant host genus Camponotus Mayr, 1861 and reported new ant-parasitoid associations. In addition, we report a new case of co-occurrence in eucharitid wasps, at the host colony level, involving a new undescribed species of Pseudochalcura Ashmead, 1904 and an unidentified species of Obeza Heraty, 1985, which attack the common but very poorly known neotropical arboreal ant Camponotus rectangularis Emery, 1890. Most attacks were solitary, but various cocoons were parasitized by two (16%) or three (8%) parasitoids. Globally, parasitism prevalence was very low (3.7%) but showed an important variability among samples. Low parasitism prevalence along with host exposure to parasitoid attack on host plants and overlapping reproductive periods of both parasitoid species may have allowed the evolution of co-occurrence. We also provided some additional data regarding the host ant nesting habits, the colony composition and new symbiotic associations with membracids and pseudococcids. The seemingly polydomous nesting habits of C. rectangularis could play a part in the reduction of parasitism pressure at the population level and, combined with occasionally important local parasitism rates, could also contribute to some parts of the colonies escaping from parasites, polydomy possibly representing an effective parasitism avoidance trait.

Medicine, Biology (General)
DOAJ Open Access 2021
Escasez de agua en Tegucigalpa, Honduras: ¿Está siendo afectada la subcuenca Guacerique por la variabilidad climática y el arrastre de sedimentos?

German Onil Rodríguez Cruz

[Introducción]: En la parte baja de la subcuenca del río Guacerique (210 km2), el embalse Los Laureles (10 millones de metros cúbicos (MMC)), es la fuente de abastecimiento del 30 % de la población de Tegucigalpa, Honduras. El agua del embalse presenta problemas en época lluviosa ligados al incremento de turbidez y color, mientras en época seca, su volumen de agua baja hasta mezclarse con los sedimentos, lo que dificulta su tratamiento. [Objetivo]: El objetivo del estudio fue evidenciar la afectación de la variabilidad climática y el arrastre de sedimentos por medio de la red hídrica de la subcuenca Guacerique, que estima la disponibilidad histórica comparado con la presencia del fenómeno de El Niño-Oscilación del Sur (ENOS) y la relación del arrastre de sedimentos hacia el embalse. [Metodología]: Se realizaron balances hídricos históricos (2001 al 2016) de la subcuenca Guacerique y se calculó la carga de sedimentos. [Resultados]: Se obtuvo una producción histórica de agua de 99.4 MMC de la subcuenca Guacerique. En presencia del fenómeno ENOS la producción fue de 73.4 MMC, en año mezcla Niño/neutral fue 103.8 MMC, en años neutrales fue de 84.3 MMC, en año mezcla Niña/neutral fue de 112.5 MMC y en año mezcla Niño/Niña fue de 216.5 MMC. El aporte de sedimentos al embalse a través de la red hídrica fue de 488.8 kg mes-1. Se tiene que el 1.7 % del total de sedimentos proviene del río Mateo, el 2.5 % de la quebrada El Ocotal y el 7.5 % de la quebrada el Achiote. [Conclusiones]: Se pudo comprobar mediante los balances hídricos, que la variabilidad climática está afectando los volúmenes de agua en la subcuenca Guacerique, y que junto al arrastre de sedimentos por el río Guacerique, se está reduciendo la capacidad de almacenamiento, lo que provoca menor disponibilidad y escasez de agua en el embalse Los Laureles. 

Human ecology. Anthropogeography, Natural history (General)

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