Hasil untuk "Natural history (General)"

J. Brown

H. Waller

DR. CLARK-KENNEDY, physician to the London Hospital and Dean of the Medical School, and well known for his original presentation of medicine in the several textbooks he has written, has now produced a book for the layman. Many will still think that for the population generally, and especially for the more neurotic section of it likely to be most interested in this type of book, a little knowledge is a dangerous thing. The author ranges widely, and on the whole wisely, over a wide variety of topics. Extreme compression can easily lead to misunderstanding and the expression of half-truths, but the author probably manages to avoid this better than most books of this kind. The book should be useful to students of the social sciences and medical students will find it stimulating in parts and of some general interest. THIS small volume represents the teaching of the late Dr. Harold Waller. As all those interested in the feeding of the newborn are aware, Dr. Waller attained an outstanding place in presenting his views on the feeding of infants by natural methods. Obstetricians and pediatricians owe a debt of gratitude to him for his great contribution to this important field. Obstetricians and paediatricians will appreciate the quality of his teaching, and midwives too will be glad to have his advice presented in this attractive book. It is concise, well written, and more. than adequately illustrated. THIS is a book which concerns every parent, though it is especially important for teachers and all those who handle children. A concise account is given of a child's behaviour from infancy to adolesence. The difficulties which may arise at various stages and the methods of treating them are described. The book is illustrated by case histories and photographs, and there is an extensive bibliography at the end of each chapter. THIS annual volume is now well known to many general practitioners. This year there are thirty-two articles by experts in various branches of medicine and surgery dealing with the treatment of such conditions as coronary thrombosis, disturbed nights in the elderly, gangrene of the extremities, tumours of the bladder, the management of colostomies and of incurable malignant disease. The articles are uniformly good and, although concerned primarily with treatment, they impart much information on symptomatology and diagnosis. The general style of the annual has always been attractive, making for easy reading. In the present volume …

T. Pawlik, K. Devon, C. Fields et al.

Hyunjeong Lee, Im Joo Rhyu

Abstract Antonie van Leeuwenhoek (1632–1723) transformed observation into science through the power of a single handmade lens. His work emerged from the visual culture of seventeenth-century Delft, where craftsmanship, optics, and artistic precision intersected. While Robert Hooke’s compound microscope introduced the idea of microscopic visualization, Leeuwenhoek’s single-lens instruments achieved far superior magnification and resolution by minimizing optical interfaces. Using these deceptively simple devices, he documented the first observations of free-living microorganisms, fungal hyphae, red blood cells, capillary flow, oral bacteria, and spermatozoa in more than two hundred letters to the Royal Society of London. But his investigations reached far beyond microbiology. Leeuwenhoek also examined the barbed structure of the bee sting, the ordered vessels of ash wood, and the geometric microstructure of crystals and salts—demonstrating that hidden organization pervades both living and non-living matter. These studies established microscopy as a universal investigative tool, capable of unifying biology, medicine, botany, and early materials science under a single optical principle. Leeuwenhoek’s work marks one of the earliest examples of how rigorous observation can redefine scientific domains. His use of a home-crafted single lens created an empirical foundation for biological microscopy that persists to this day. The legacy of his minimalist optical design also survives in the digital age: modern clip-on smartphone microscopes and paper-based platforms such as the Foldscope reproduce the same single-lens principle through micro-optics mounted directly onto digital sensors. Three and a half centuries later, his work continues to remind us that new worlds do not emerge from new theories alone, but from new ways of seeing.

Andrew C. Poje, Takaya Uchida, Takaya Uchida et al.

We address the question of separating the ocean’s deterministic response to time-dependent forcing from its intrinsic chaotic variability. Ideally, one could compute the ensemble mean directly without performing numerous realizations, but this requires knowledge or closure of the second-order statistics — the classical turbulent-closure problem, here recast for a non-equilibrium, geophysical setting. Building on the ideas of nonlinear midlatitude ocean adjustment, we examine this problem using idealized quasi-geostrophic (QG) double-gyre ensembles subjected to episodic temporal variations in wind forcing. Our objective here is not to develop a subgrid parameterization of unresolved eddies, but rather to construct and test prognostic equations for the ensemble mean itself, using the simplest possible closure assumptions. We find that the performance of ensemble mean closures is highly dependent on the spatiotemporal structure of the forcing. Under slowly varying forcing, approximate closures reproduce the mean evolution reasonably well; under rapidly varying, near-zero-mean forcing, the simplest ensemble-mean closures fail, even at the level of basin-averaged total energy and enstrophy. In both regimes, the ensemble-mean response is not simply the accumulated imprint of the applied forcing, but instead appears as a continuing, non-equilibrated dialogue between the mean and eddy fields.

Jiangtao Bai, Yutong Yan, Xinyun Bai

In recent years, the International Maritime Organization (IMO) has set strict emission standards for the shipping industry, which has raised high demands for ship emission reduction technologies. This review analyzes the research status of ship emission reduction technologies using bibliometric methods based on 714 publications from the Social Science Citation Index (SSCI) and SCI-Expanded (SCIE) databases from 2000 to 2024, and use VOSviewer software for the visualization of publications. It identifies key trends, productive entities and key contributors, and research hotspots in the field. The core findings are that green power technologies, digital intelligence technologies, and emission reduction technologies are current focal points. Future research should focus on finding optimal solutions for alternative marine fuels, clarifying the low-carbon transformation pathways for ships, and promoting effective follow-up actions from all relevant parties.

Christopher K Starr, Craig A. Western, Aidan D. Farrell

      Against the hypothesis that the ability to defend the brood by stinging is a key enabling mechanism in the origin of sociality in the Hymenoptera, it was claimed that small colonies do not defend the nest against large adversaries. We report on a test of this claim. Using a simulated vertebrate intruder, we provoked early colonies of three species of paper wasps (Polistes) until all adult females had either attacked or fled. In each species, a substantial fraction of adult females attacked the intruder, with an approximately linear relationship between the total number of females and the number attacking, consistent with the initial hypothesis. This experimental approach also presents a novel method for comparing attack-readiness between species, developmental stages, or experimental conditions.

Samantha King, Antoine Saint-Amand, Brian K. Walker et al.

Since the 1980s, populations of Acropora cervicornis and A. palmata have experienced severe declines due to disease and anthropogenic stressors; resulting in their listing as threatened, and their need for restoration. In this study, larval survival and competency data were collected and used to calibrate a very high-resolution hydrodynamic model (up to 100m) to determine the dispersal patterns of Acropora species along the Florida’s Coral Reef. The resulting connectivity matrices was incorporated into a metapopulation model to compare strategies for restoring Acropora populations. This study found that Florida’s Coral Reef was historically a well-connected system, and that spatially selective restoration may be able to stimulate natural recovery. Acropora larvae are predominantly transported northward along the Florida’s Coral Reef, however southward transport also occurs, driven by tides and baroclinic eddies. Local retention and self-recruitment processes were strong for a broadcast spawner with a long pelagic larval duration. Model simulations demonstrate that it is beneficial to spread restoration effort across more reefs, rather than focusing on a few reefs. Differences in population patchiness between the Acropora cervicornis and A. palmata drive the need for different approaches to their management plans. This model can be used as a tool to address the species-specific management to restore genotypically diverse Acropora populations on the Florida’s Coral Reef, and its methods could be expanded to other vulnerable populations.

Fabio Rindi, Fabio Rindi, Alba Vergés et al.

Active marine restoration is strongly encouraged to prevent the loss of the valuable habitats formed by Cystoseira sensu lato species, since they enhance biodiversity and preserve ecosystem functions and services. Current restoration interventions are mainly based on recruitment enhancement methods by deploying bags with fertile receptacles in situ or by outplanting juveniles grown ex situ under laboratory conditions. These methods allow the recovery of endangered species avoiding the depletion of the donor populations. In all cases, a priori knowledge of the reproductive phenology and recruitment periods of the species to be restored is essential, since the success of restoration techniques relies on collecting fertile branches and the obtention and survival of recruits. For their collection, identified donor populations characterized by dense Cystoseira s.l. cover should be studied. Specifically, monitoring the reproductive phenology of populations is crucial to detect the period of the year in which they develop mature reproductive structures and to understand how it might be linked to environmental conditions. Then, these general patterns on the reproductive phenology of Cystoseira s.l. species are essential to determine the most suitable time and conditions to plan for the most effective restoration action. Here, we provide a cost-effective and friendly protocol that can be easily and widely implemented for all Cystoseira s.l. species. We pose that this protocol provides a standardized and useful methodology to understand the environmental factors driving the optimal periods for sampling fertile branches across the Mediterranean Sea, and thus it can be an essential tool to plan future restoration actions.

Hu Xianhui, Zhang Ziyi, Wang Zicheng et al.

[Objective] The temporal and spatial evolution law of non-point source pollution on cultivated land in the Dongting Lake plain from 2009 to 2019 was studied to define the decoupling relationship between cultivated land non-point source pollution and agricultural production in order to provide a scientific reference for the treatment of non-point source pollution on cultivated land in the Dongting Lake plain. [Methods] The application rates of chemical fertilizers and pesticides in addition to grain yield per unit area were used to describe the status of cultivated land non-point source pollution and agricultural production in the Dongting Lake plain. Spatial analysis and a decoupling model were used to determine the temporal and spatial evolution law and the decoupling relationship between non-point source pollution on cultivated land and agricultural production in the Dongting Lake plain from 2009 to 2019. [Results] ① From 2009 to 2019, the application rates of chemical fertilizers and pesticides in the Dongting Lake plain initially increased and then decreased, and exhibited obvious spatial differences. The productivity of chemical fertilizers and pesticides showed an overall upward trend; ② From 2009 to 2019, grain yield per unit area in the Dongting Lake plain showed an inverted U-shaped trend, with obvious spatial differences; ③ The decoupling relationship between grain yield per unit area and the rates of chemical fertilizer and pesticide applications in the Dongting Lake plain showed obvious stage characteristics: the first stage was a fluctuation period (2009—2013); the second stage was a strong decoupling period (2014—2015); and the third stage was a weak negative decoupling and declining decoupling period (2016—2019); ④ The decoupling relationship between agricultural production and cultivated land non-point source pollution in the Dongting Lake plain gradually showed high convergence and aggregation characteristics on the county-level spatial scale. [Conclusion] Efforts should be taken to further strengthen the prevention and control of the source of non-point source pollution on cultivated land through the use of a variety of measures in order to improve grain yield, and to finally realize the strong decoupling between cultivated land non-point source pollution and agricultural production.

Tian Xie, Andong Wang, Shanze Li et al.

Burrowing crabs are widely distributed and have large populations in estuarine wetlands. Crab excavation can have potentially significant bioturbation effects on the vertical structure of sediments, and the processes of nutrients deposition and mineralization. However, the effects of crab micro activities on the geochemical cycling processes of the whole estuarine ecosystems are not clear, specifically the contributions of burrowing crabs to sediment and nutrients turnover in coastal ecosystems. Due to the lack of knowledge on crab burrowing behavior and borrow morphology, it is difficult to accurately estimate the excavation and turnover volumes of crabs. Therefore, this study examined the bioturbation activity of the crab Helice tientsinensis in western Pacific estuary ecosystems by analyzing their burrow morphology and local sediment properties. The common burrow shapes of Helice tientsinensis were J- and Y-shaped burrows. Burrow morphological characteristics such as total burrow depth, curve burrow length, burrow volume, and opening diameter significantly differed among tidal zones. Crab carapace size, water depth, soil hardness, and bulk density were the main factors driving burrow morphology. Sediment excavation by crabs was ~50 times greater than the deposition of sediment into crab burrows. The net transported amounts of sediment (31.66–33.18 g·d-1·m-2) and nutrients (total nitrogen: 0.075–0.090 g·d-1·m-2, total carbon: 3.96–4.55 g·d-1·m-2, and organic matter: 0.44–0.77 g·d-1·m-2) were mainly from the belowground sediment to the surface. These results highlighted the important role of crabs in sediment and nutrients cycling within coastal estuary ecosystems.

P. Bloom

Fátima Aparecida Sonoda, Priscilla Barbosa Alcantara da Silva, Laura Rodrigues Ribeiro et al.

As áreas protegidas são reconhecidas como principal estratégia na conservação in situ da biodiversidade, sendo utilizadas como um indicador válido e mensurável do progresso na conservação da biodiversidade remanescente na esfera mundial. O objetivo deste artigo foi estruturar uma base de informações de ocorrência de mamíferos nas unidades de conservação (UC) do Pantanal e avaliar a efetividade das mesmas quanto à proteção da mastofauna presente no bioma. No levantamento de dados de mamíferos presentes nas UC de proteção integral do bioma, foram registradas 112 espécies. Somando-se os registros das UC de uso sustentável, obteve-se o total de 125 espécies. As UC de proteção integral apresentaram registro de aproximadamente 68% das espécies listadas para o bioma pantaneiro. Acrescidos dos registros das UC de uso sustentável, totalizou-se aproximadamente 76% das espécies. Quanto às espécies ameaçadas, foram contabilizadas 22 espécies presentes com pelo menos um registro na rede de UC de proteção integral do bioma. Uma abordagem voltada à construção de uma rede de UC com amplos objetivos de manejo e de conservação é a principal estratégia para garantir a sustentabilidade do bioma, ainda pouco representado no sistema nacional (4,65% de seu território protegido).

David L. Bachman, P. Wolf, R. Linn et al.

G. Booy, Rob J. J. Hendriks, M. Smulders et al.

Gisela Cassiodoro, Josefina Flores Coni, Agustín Agnolin et al.

En el centro-oeste de la provincia de Santa Cruz (Argentina) las puntas de proyectil que predominan desde el Holoceno temprano hasta el Holoceno medio se corresponden con una morfología que no presenta pedúnculo. Por tal razón, este diseño apedunculado ha sido considerado como un fósil guía para la asignación cronológica de contextos arqueológicos. En este trabajo se presentan las características de esta clase artefactual recuperada en diferentes sectores de la región de estudio. Se aborda su distribución espacial, las cronologías absolutas y relativas asignadas, las materias primas utilizadas y aspectos de su morfología. Estas puntas están heterogéneamente distribuidas, se asignan a cronologías previas a los 2000 años AP, predomina el uso de la obsidiana negra y se registra variabilidad en morfologías.  El análisis de las puntas apedunculadas nos permite discutir algunas cuestiones del poblamiento humano desde el comienzo del Holoceno y su trayectoria temporal posterior.

Julia Rulent, Julia Rulent, Francisco M. Calafat et al.

Accurately resolving coastal Total Water Levels (TWL) is crucial for socio-economic and environmental reasons. Recent efforts in satellite altimetry and numerical modeling have improved accuracy over near-shore areas. In this study we used data from tide gauges (TGs), SAR-mode altimetry from two satellites [Sentinel-3A (S3) and CryoSat-2 (C2)], and a state-of-the-art high-resolution regional coupled environmental prediction model (Amm15) to undertake an inter-comparison between the observations and the model. The aim is to quantify our capability to measure TWL around the United Kingdom coast, and to quantify the capacity of the model to represent coastal TWL. Results show good agreement between the satellite and TG data [the mean correlation (R) over seventeen TGs between June 2016 and September 2017 is 0.85 for S3 and 0.80 for C2]. The satellite-model comparison shows that the variability is well captured (R = 0.98 for both satellite), however, there is an offset (−0.23 m for S3, −0.15 m for C2) between the satellite and model data, that is near-constant across the domain. This offset is partly attributed to the difference in the reference level used by the satellites and the model, and residual differences linked to the temporal resolution of the model. The best agreement between model and satellite is seen away from the coast, further than 3–4 km offshore. However, even within the coastal band, R remains high, ∼0.95 (S3) and ∼0.96 (C2). In conclusion, models are still essential to represent TWL in coastal regions where there is no cover from in-situ observations, but satellite altimeters can now provide valuable observations that are reliable much closer to the coast than before.

K. Drummond, S. Bradley, M. Peterson-badali et al.

Christopher T. Griffin, Lauren S. Bano, Alan H. Turner et al.

Understanding growth patterns is central to properly interpreting paleobiological signals in tetrapods, but assessing skeletal maturity in some extinct clades may be difficult when growth patterns are poorly constrained by a lack of ontogenetic series. To overcome this difficulty in assessing the maturity of extinct archosaurian reptiles—crocodylians, birds and their extinct relatives—many studies employ bone histology to observe indicators of the developmental stage reached by a given individual. However, the relationship between gross morphological and histological indicators of maturity has not been examined in most archosaurian groups. In this study, we examined the gross morphology of a hypothesized growth series of Dromomeron romeri femora (96.6–144.4 mm long), the first series of a non-dinosauriform dinosauromorph available for such a study. We also histologically sampled several individuals in this growth series. Previous studies reported that D. romeri lacks well-developed rugose muscle scars that appear during ontogeny in closely related dinosauromorph taxa, so integrating gross morphology and histological signal is needed to determine reliable maturity indicators for early bird-line archosaurs. We found that, although there are small, linear scars indicating muscle attachment sites across the femur, the only rugose muscle scar that appears during ontogeny is the attachment of the M. caudofemoralis longus, and only in the largest-sampled individual. This individual is also the only femur with histological indicators that asymptotic size had been reached, although smaller individuals possess some signal of decreasing growth rates (e.g., decreasing vascular density). The overall femoral bone histology of D. romeri is similar to that of other early bird-line archosaurs (e.g., woven-bone tissue, moderately to well-vascularized, longitudinal vascular canals). All these data indicate that the lack of well-developed femoral scars is autapomorphic for this species, not simply an indication of skeletal immaturity. We found no evidence of the high intraspecific variation present in early dinosaurs and other dinosauriforms, but a limited sample size of other early bird-line archosaur growth series make this tentative. The evolutionary history and phylogenetic signal of gross morphological features must be considered when assessing maturity in extinct archosaurs and their close relatives, and in some groups corroboration with bone histology or with better-known morphological characters is necessary.

M. Brocx, V. Semeniuk

Unlike other estuaries Nationally in Australia, the Walpole-Nornalup Inlets is unique complex twin-basin ria estuary in the most humid part of Western Australia. The estuary fronts the oceanographically-dynamic Southern Ocean and, with the high annual rainfall, it provides a range of estuarine landforms, estuarine peripheral wetlands, a dynamic sand barrier that records climate changes and, with its microtidal setting, it provides examples of complex riverine-to-marine dynamics such as intra-basinal gyring. A range of geological to estuarine features that are of geoheritage significance and available for exploration and explanation as geotrails include: (1) the Precambrian geology, (2) the stratigraphy of the Cainozoic Werillup Formation, 4. Cainozoic weathering, sedimentation, and climate history, with a very wet climate to produce erosionally-resistant quartz grain lags, (5) Cainozoic to Quaternary formation of a rock tombolo, (6) the complex estuarine shorelines and history, and (7) complex estuarine processes and history. As an ensemble of geological and other natural history features, Walpole-Nornalup Inlets system also provides a case study of a systematic approach, using the Geoheritage Tool-kit, of identifying and evaluating different natural values. This forms the foundation for to baseline monitoring (for environmental management) and tourism to explore through geological time the natural history of this geologically, and biologically rich location. Keywords: Walpole-Nornalup inlets, Western Australia, Estuary, Geoheritage, Marine Park