Hasil untuk "Natural history (General)"

C. Canavan, J. West, T. Card

Irritable bowel syndrome (IBS) is a functional condition of the bowel that is diagnosed using clinical criteria. This paper discusses the nature of the diagnostic process for IBS and how this impacts epidemiological measurements. Depending on the diagnostic criteria employed, IBS affects around 11% of the population globally. Around 30% of people who experience the symptoms of IBS will consult physicians for their IBS symptoms. These people do not have significantly different abdominal symptoms to those who do not consult, but they do have greater levels of anxiety and lower quality of life. Internationally, there is a female predominance in the prevalence of IBS. There is 25% less IBS diagnosed in those over 50 years and there is no association with socioeconomic status. IBS aggregates within families and the genetic and sociological factors potentially underlying this are reviewed. Patients diagnosed with IBS are highly likely to have other functional disease and have more surgery than the general population. There is no evidence that IBS is associated with an increased mortality risk. The epidemiological evidence surrounding these aspects of the natural history is discussed.

J. Willis

L. Lohmander, P. Englund, L. Dahl et al.

A. Chopra

B. Maron

Pablo Capilla‐Lasheras, Alice Risely

Long‐distance bird migration is one of the most metabolically and immunologically challenging feats in the animal kingdom, with birds often needing to double their weight in a matter of days and facing increased exposure to novel pathogens. The physiological and behavioural adaptations required to survive such journeys may be facilitated by the gut microbiome, a diverse community of symbiotic microbes that produce rare nutrients, fatty acids, and immune compounds that can confer rapid physiological adaptations to changing environmental conditions. However, the causal role of the gut microbiome in regulating migration physiology remains a mystery. In this review, we synthesize current knowledge of gut microbiome composition and function during migration, outline possible mechanisms by which changes in the gut microbiome could benefit migrants, and identify future research priorities. We find that active migration is usually associated with reduced diversity of the gut microbiome and with the expansion of several study‐specific taxa. Additionally, some microbial traits have been found to correlate with host condition and fat deposits during migration. However, there remains little understanding of how changes in the gut microbiome during migration relate to most physiological parameters, the molecular mechanisms linking the gut microbiome to host physiology during migration, or the underlying ecological, dietary, and intrinsic drivers of gut microbiome changes across the migratory cycle. Our review draws from examples across non‐migratory systems to explore how gut microbiomes could adaptively regulate physiological traits relevant to migration. We highlight the need for studies that connect gut and circulating metabolites and for experimental studies that test the underlying drivers of gut microbial and metabolite dynamics in controlled settings. Given its diverse physiological demands and ubiquity, bird migration presents an excellent model system to investigate the adaptive potential of the gut microbiome in natural populations.

Marco Genovese, Ivano Ruo-Berchera

Quantum illumination represents one of the most interesting examples of quantum technologies. On the one hand, it can find significant applications; on the other hand, it is one of the few quantum protocols robust against noise and losses. Here we present a short summary of the history of this quantum protocol.

Seungwook Han, Jyothish Pari, Samuel J. Gershman et al.

Large Language Models (LLMs) have demonstrated impressive real-world utility, exemplifying artificial useful intelligence (AUI). However, their ability to reason adaptively and robustly -- the hallmarks of artificial general intelligence (AGI) -- remains fragile. While LLMs seemingly succeed in commonsense reasoning, programming, and mathematics, they struggle to generalize algorithmic understanding across novel contexts. Our experiments with algorithmic tasks in esoteric programming languages reveal that LLM's reasoning overfits to the training data and is limited in its transferability. We hypothesize that the core issue underlying such limited transferability is the coupling of reasoning and knowledge in LLMs. To transition from AUI to AGI, we propose disentangling knowledge and reasoning through three key directions: (1) pretaining to reason using RL from scratch as an alternative to the widely used next-token prediction pretraining, (2) using a curriculum of synthetic tasks to ease the learning of a reasoning prior for RL that can then be transferred to natural language tasks, and (3) learning more generalizable reasoning functions using a small context window to reduce exploiting spurious correlations between tokens. Such a reasoning system coupled with a trained retrieval system and a large external memory bank as a knowledge store can overcome several limitations of existing architectures at learning to reason in novel scenarios.

Shijie Zhou, Weidi Zhu, Yuhang He et al.

Achieving carbon neutrality in wastewater treatment plants relies heavily on mainstream anaerobic ammonia oxidation. However, the stability of this process is often compromised, largely due to the significant influence of microbial morphology. This study analyzed 208 microbial samples using bioinformatics and machine learning (ML) across four different morphologies: Suspended Sludge (SS), Biofilm, Granular Sludge (GS) and the Integrated Fixed-film Activated Sludge process (IFAS). The results revealed IFAS’s notably complex and stable community structure, along with the identification of endemic genera and common genera among the four microbial morphologies. Through co-occurrence network analysis, the interaction between microorganisms of various genera was displayed. Utilizing the Extreme Gradient Boosting (XGBoost) model, a ML modeling framework based on microbiome data was developed. The ML-based feature importance analysis identified LD-RB-34 as a key organism in SS and BSV26 was an important bacterium in IFAS. Additionally, functional bacteria KF-JG30-C25 occupied a higher proportion in GS, and Unclassified Brocadiaceae occupied a higher proportion in Biofilm. Furthermore, dissolved oxygen, temperature and pH were identified as the primary factors determining microbial communities and influencing anammox activity. Overall, this study deepens our understanding of bacterial communities to enhance the mainstream anammox nitrogen removal.

Annet Konings, Mariia Marinichenko, Oleksii Mikulenko et al.

Primordial gravitational waves propagate almost unimpeded from the moment they are generated to the present epoch. Nevertheless, they are subject to convolution with a non-trivial transfer function. Within the standard thermal history, shifts in the temperature-redshift relation combine with damping effects by free streaming neutrinos to non-trivially process different wavelengths during radiation domination, with subsequently negligible effects at later times. Presuming a nearly scale invariant primordial spectrum, one obtains a characteristic late time spectrum, deviations from which would indicate departures from the standard thermal history. Given the paucity of probes of the early universe physics before nucleosynthesis, it is useful to classify how deviations from the standard thermal history of the early universe can be constrained from observations of the late time stochastic background. The late time spectral density has a plateau at high frequencies that can in principle be significantly enhanced or suppressed relative to the standard thermal history depending on the equation of state of the epoch intervening reheating and the terminal phase of radiation domination, imprinting additional features from bursts of entropy production, and additional damping at intermediate scales via anisotropic stress production. In this paper, we survey phenomenologically motivated scenarios of early matter domination, kination, and late time decaying particles as representative non-standard thermal histories, elaborate on their late time stochastic background, and discuss constraints on different model scenarios.

Hee Suk Yoon, Eunseop Yoon, Joshua Tian Jin Tee et al.

Multimodal Dialogue Response Generation (MDRG) is a recently proposed task where the model needs to generate responses in texts, images, or a blend of both based on the dialogue context. Due to the lack of a large-scale dataset specifically for this task and the benefits of leveraging powerful pre-trained models, previous work relies on the text modality as an intermediary step for both the image input and output of the model rather than adopting an end-to-end approach. However, this approach can overlook crucial information about the image, hindering 1) image-grounded text response and 2) consistency of objects in the image response. In this paper, we propose BI-MDRG that bridges the response generation path such that the image history information is utilized for enhanced relevance of text responses to the image content and the consistency of objects in sequential image responses. Through extensive experiments on the multimodal dialogue benchmark dataset, we show that BI-MDRG can effectively increase the quality of multimodal dialogue. Additionally, recognizing the gap in benchmark datasets for evaluating the image consistency in multimodal dialogue, we have created a curated set of 300 dialogues annotated to track object consistency across conversations.

Brooke K. Sullivan, Brooke K. Sullivan, Daniel L. Martin et al.

Labyrinthula are unicellular protists occupying diverse spatial and functional niches, including various roles in host and ecological function, fatty acid production, pandemic marine disease and saprobic decomposition. Labyrinthula species span tropical and temperate climates and have been isolated from each marine coastal ecosystem tested. Our understanding of primary cellular and molecular functions of Labyrinthula has substantially progressed through a combination of increased global investments, research interest and technological advances. Recent advances in molecular techniques provide a toolkit for advancing ecological questions in marine infectious disease in seagrass meadows around the world. Here we provide a comprehensive review of relevant ecological and molecular techniques used in long-term research and the progression of Labyrinthula scholarship. Our aims in preparing this review are to: 1) share, compare and advance global Labyrinthula protocols, 2) increase accessibility to robust methodology to encourage the uptake of Labyrinthula-based questions into marine studies of molecular and ecological qualities of Labyrinthula and 3) encourage uptake of robust Labyrinthula-based questions into coastal marine studies, while also encouraging international collaborative networks across multiple fields. Lastly, we discuss gaps in the over 100 years of Labyrinthula research and opportunities for expanding research on this model marine organism.

Quandong Xin, Quandong Xin, Quandong Xin et al.

The Western Subarctic Gyre (WSG) is a cyclonic upwelling gyre in the northwest subarctic Pacific, which is a region with a high concentration of nutrients but low chlorophyll. We investigated the community structure and spatial distribution of phytoplankton in this area by using HPLC-pigment CHEMTAX (a chemotaxonomy program) and metabarcoding sequencing during the summer of 2021. The phytoplankton community showed significant differences between the two methods. The CHEMTAX analyses identified eight major marine phytoplankton assemblages. Cryptophytes were the major contributors (24.96%) to the total Chl a, followed by pelagophytes, prymnesiophytes, diatoms, and chlorophytes. The eukaryotic phytoplankton OTUs obtained by metabarcoding were categorized into 149 species in 96 genera of 6 major groups (diatoms, prymnesiophytes, pelagophytes, chlorophytes, cryptophytes, and dinoflagellates). Dinoflagellates were the most abundant group, accounting for 44.74% of the total OTUs obtained, followed by cryptophytes and pelagophytes. Sixteen out of the 97 identified species were annotated as harmful algal species, and Heterocapsa rotundata, Karlodinium veneficum, and Aureococcus anophagefferens were assigned to the abundant group (i.e., at least 0.1% of the total reads). Nutrients were more important in shaping the phytoplankton community than temperature and salinity. The 24 stations were divided into southern and northern regions along 44°N according to the k-means method, with the former being dominated by high Chl a and low nutrients. Although different phytoplankton assemblages analyzed by the two methods showed various relationships with environmental factors, a common feature was that the dinoflagellate proportion showed a significantly negative correlation with low nutrients and a positive correlation with Chl a.

Shuntaro Yada, Eiji Aramaki

Electronic health records (EHRs), which contain patients' medical histories, tend to be written in freely formatted (unstructured) text because they are complicated by their nature. Quickly understanding a patient's history is challenging and critical because writing styles vary among doctors, which may even cause clinical incidents. This paper proposes a Health Record Timeliner system (HeaRT), which visualises patients' clinical histories directly from natural language text in EHRs. Unlike only a few previous attempts, our system achieved feasible and practical performance for the first time, by integrating a state-of-the-art language model that recognises clinical entities (e.g. diseases, medicines, and time expressions) and their temporal relations from the raw text in EHRs and radiology reports. By chronologically aligning the clinical entities to the clinical events extracted from a medical report, this web-based system visualises them in a Gantt chart-like format. Our novel evaluation method showed that the proposed system successfully generated coherent timelines from the two sets of radiology reports describing the same CT scan but written by different radiologists. Real-world assessments are planned to improve the remaining issues.

L. Brendonck, L. De Meester

Katherine A. Castagno, Katherine A. Castagno, Neil K. Ganju et al.

As coastal communities grow more vulnerable to sea-level rise and increased storminess, communities have turned to nature-based solutions to bolster coastal resilience and protection. Marshes have significant wave attenuation properties and can play an important role in coastal protection for many communities. Many restoration projects seek to maximize this ecosystem service but how much marsh restoration is enough to deliver measurable coastal protection benefits is still unknown. This question is critical to guiding assessments of cost effectiveness and for funding, implementation, and optimizing of marsh restoration for risk reduction projects. This study uses SWAN model simulations to determine empirical relationships between wave attenuation and marsh vegetation. The model runs consider several different common marsh morphologies (including systems with channels, ponds, and fringing mudflats), vegetation placement, and simulated storm intensity. Up to a 95% reduction in wave energy is seen at as low as 50% vegetation cover. Although these empirical relationships between vegetative cover and wave attenuation provide essential insight for marsh restoration, it is also important to factor in lifespan estimates of restored marshes when making overall restoration decisions. The results of this study are important for coastal practitioners and managers seeking performance goals and metrics for marsh restoration, enhancement, and creation.

Natasha Gillies, Chris Tyson, Joe Wynn et al.

Many species that provide care for their offspring in tandem with a partner coordinate their activities to maximise the efficiency of their investment. However, it is not well known exactly how this coordination is achieved. Manx shearwaters Puffinus puffinus are Procellariiform seabirds that exhibit a dual foraging strategy during chick provisioning in which long foraging trips to maintain condition are alternated with short, frequent trips to feed the offspring. This strategy is employed in a coordinated manner between the parents, with one making short trips while the other takes a single long trip. Previous work revealed that a complementary switch in foraging trip type is initiated by the parents following a synchronous visit to the nest. We used a combination of observational data and experimental manipulation to examine the mechanisms that may underlie this behaviour. Specifically, we investigated the evidence that physical reunion is necessary to induce a switch in trip type, whether parents change their behaviour to maximise the probability of partner encounter, and whether indirect cues gained from the chick could inform a switch in behaviour. In our experimental approach, we manipulated the information adults had available to them by supplementarily feeding chicks to alter their begging behaviour. We found no support for the role of physical reunion or indirect cues in the coordination of care in this species. We discuss the possibility that the patterns of alternated provisioning observed during chick rearing in Manx shearwaters may emerge through entrainment during the well‐coordinated incubation period preceding chick provisioning.

Joan Milam, Michael Cunningham‐Minnick, Henry Patrick Roberts et al.

Abstract Forest management is often practiced to enhance conditions for wildlife, including native bees. Evaluations of the effects of forest management on bees have shown that abundance and diversity are higher in newly created early‐successional conditions. To date, studies have restricted sampling to the forest understory; however, recent research finds that bee abundance is as high or higher in forest canopies than in understories, suggesting that previous observations of substantially greater bee abundance and diversity in recently managed areas could be an artifact of incomplete sampling of the vertical gradient within forests. To examine the potential implications of sampling biases associated with the failure of previous studies to include canopy samples in comparisons of managed and unmanaged forests, we sampled bees within a recently harvested forest as well as the understory and canopy of adjacent unmanaged forest. Bee abundance and diversity were an order of magnitude higher in managed areas compared to the unmanaged forest, even when understory and canopy samples were combined. These results suggest that not sampling the canopy is inconsequential with respect to the broadly reported conclusion that managed areas support more abundant and diverse bee communities than surrounding forest cover.

Subrata Sarker, Deen Mohammad, Siam Ahmed Nabil et al.

Variability in physical and chemical processes in the marine ecosystem significantly influences the niche ecology of primary producers. However, studies are limited to understand the role of variability in environmental conditions on the niche dynamics of phytoplankton. Therefore, in this study we aimed to understand the role of environmental noise on the niche dynamics of phytoplankton species. This study performed numerical simulations by extending the classic Rosenzweig–MacArthur, predator–prey model for multiple species. We considered the characteristics timescale of seasonal sea surface temperature as environmental noise. Our study found that the oscillatory fluctuation of biomass, variation in carrying capacity, no competitive exclusion, and non-equilibrium state in periodic fluctuation of species biomass enables species to coexist in a noise-induced system. In addition, a high amplitude in species biomass fluctuation at a higher environmental noise was found as another potential coexistence mechanism. Our simulations found that the mean niche and niche width of species are significantly related to environmental noise (R2 = 0.93 and 0.98, respectively). We observed a shift in mean niche conditions of species with the change in environmental noise. Niche overlapping between species decreased significantly with the increase in environmental noise (R2 = 0.95). Our study will serve as a baseline to understand the complexity of phytoplankton niche dynamics in a variable environment.

Daniela Silvia Pace, Daniela Silvia Pace, Sara Ferri et al.

Sociality and ecological drivers that can influence individual association patterns are infrequently considered in wildlife management, although they are essential aspects affecting animals’ responses to both human-related pressures and conservation strategies. In common bottlenose dolphins (Tursiops truncatus), sex-specific social dynamics and interactions with anthropogenic activities may affect grouping and induce changes in relationships between individuals. Out of a total of 347 individuals, we assessed the level of association among 68 bottlenose dolphins that have been sighted more than five times near the Roman coast (central Mediterranean Sea, Italy). The half-weight index (HWI) of dyadic associations, their network relations, and stability over time were investigated by using the SOCPROG software. Outcomes showed that females were more strongly associated than other individuals, with both preferred constant short-term associations and random long-term associations, possibly resulting in greater success in rearing young. Individuals interacting with the bottom trawl fishery showed weaker and short-term associations. Temporary disruption of individual associations during interaction with fishery and the relatively low number of females with calves participating in depredation seem to denote both the opportunistic nature of interactions with fishing vessels and the offspring-related protection strategy. The results show that the dolphins in this region maintain a complex but flexible social structure that varies with local biological requirements and is resilient to anthropogenic pressures.