Hasil untuk "Natural history (General)"

Yingjie Kang, Zewen Zhang, Zeyu Zhang et al.

This paper investigates the optimal design of base-isolated structures equipped with tuned inerter dampers (TIDs) subjected to various ground motions. The Clough–Penzien model is employed to simulate the power spectrum of three types of ground motions: far-fault, near-fault without pulse subset, and near-fault with pulse subset, with the relevant parameters identified based on actual ground motions. The optimal parameters of the TID for base-isolated structures are determined using the H² optimization criterion to reduce the structural displacement response. The impact of relevant design properties about the optimal parameters is analyzed. The seismic control effectiveness of the TID for 5-storey, 10-storey, and 15-storey base-isolated structures with varying heights is then evaluated through time history analysis, considering far-fault, near-fault without pulse subset, and near-fault with pulse subset ground motions. The main conclusions of this study are as follows: the ground motion type, the natural vibration period of the isolated structure, the damping ratio of the isolated structure and the mass ratio of the TID all affect the optimal parameters and should be analyzed based on specific circumstances. The control effectiveness of the TID on displacement and acceleration response is more pronounced under far-fault ground motion than under near-fault ground motion. The TID equipped in the isolation storey exhibits considerable effectiveness in controlling the seismic response of 5-storey and 10-storey base isolated structures, while it exhibits weaker control over the seismic response of the 15-storey structure. Additionally, while the TID primarily targets displacement response control, it also exhibits substantial control over the absolute acceleration response of the structure.

Mônica da Costa Lima, Fredy Alvarado, Helder F.P. de Araujo

A research challenge for this century is the integration of highly productive and sustainable landscapes. This issue is crucial for semi-arid regions, where historical land management practices have led to habitat loss and desertification processes. In this study, we evaluated the relative effects of habitat amount (forest cover), landscape heterogeneity (landscape diversity) and spatial arrangement (forest fragmentation and edge density) on bird α and β-diversity in the Caatinga tropical dry forest of northeastern Brazil. We separately assessed the complete bird assemblage and three different ecological groups (forest specialist, habitat generalist and open-area specialist species). Our results indicate that habitat amount is the main positive driver of α and β-diversity of birds in the Caatinga landscapes. However, landscape heterogeneity emerged as an important positive driver for habitat generalist and open-area specialist species. Our results highlight the importance of landscape-scale forest cover and increasing landscape heterogeneity on productive lands as a strategy to balance food production and biodiversity conservation in dry forest regions such as the Caatinga.

Adalberto Navidad Sánchez, Carlos Alberto Pérez Ramírez, Lilia Zizumbo Villarreal

[Introducción]: A lo largo del proceso histórico, el capitalismo ha propiciado el despojo tanto de tierras como de recursos e incide en la separación de las personas productoras del campo de sus medios de vida. En esta realidad, la actividad turística ha sido impulsada con fines de acumulación, en detrimento de la conservación ambiental y las condiciones de vida de las poblaciones locales, por lo que es necesario contribuir a la discusión de perspectivas teórico-metodológicas que permitan comprender la compleja situación actual. [Objetivo]: El trabajo tuvo como objetivo relacionar diversos planteamientos teóricos y metodológicos que han sido empleados para el abordaje de la expansión y las dinámicas capitalistas asociadas al desarrollo de la actividad turística, con el propósito de establecer pautas para su análisis, las cuales permitan comprender los efectos ambientales que está generado en el contexto iberoamericano. [Metodología]: Se realizó un análisis crítico del acervo documental, que permitió identificar los diversos enfoques disciplinarios, aportes teóricos y metodológicos que han sido empleados para el abordaje de este objeto de estudio. [Resultados]: Se delinean diversas pautas y un diseño estructural, soportados en diversos tópicos, categorías y subcategorías de análisis, los cuales posibilitarían comprender los efectos ambientales que la actividad está generando. [Conclusiones]: Esta propuesta puede dar soporte teórico y metodológico para el desa- rrollo de una investigación empírica, aunque es necesario avanzar en el diseño procedimental y la determinación de los medios verificadores.

Mohammed Tayeeb Hasan, Nikolaos Tsantalis, Pouria Alikhanifard

Tracking statements in the commit history of a project is in many cases useful for supporting various software maintenance, comprehension, and evolution tasks. A high level of accuracy can facilitate the adoption of code tracking tools by developers and researchers. To this end, we propose CodeTracker, a refactoring-aware tool that can generate the commit change history for code blocks. To evaluate its accuracy, we created an oracle with the change history of 1,280 code blocks found within 200 methods from 20 popular open-source project repositories. Moreover, we created a baseline based on the current state-of-the-art Abstract Syntax Tree diff tool, namely GumTree 3.0, in order to compare the accuracy and execution time. Our experiments have shown that CodeTracker has a considerably higher precision/recall and faster execution time than the GumTree-based baseline, and can extract the complete change history of a code block with a precision and recall of 99.5% within 3.6 seconds on average.

SUN Jianwei, JIA Xu, LIU Xiangdong et al.

BACKGROUND As the significant factor of the accumulation of heavy metals in farmland soils, mineral activities such as mining, traffic and mineral processing and smelting allow heavy metals to spread into the surrounding environment by water or atmospheric deposition, and finally collected into the soil, causing heavy metal pollution in the surrounding farmland soil. Heavy metals pollution in soils especially in farmland soils around the mining area thus has received great attention in the field of environmental pollution. Located in the middle reaches of the Yellow River watershed, the gold mining area in western Henan is an extremely important gold deposit area with great prospecting potential in China for the strong late Yanshan acidic magmatic activity and the extremely favorable metallogenic geological conditions, in which more than 40 large, medium or small gold deposits have been discovered. Under the background of ecological protection and high-quality development in the Yellow River watershed, the western Henan gold mining area, with a long history of gold mining development, lacks more attention to the accumulation, spatial distribution and ecological risk of heavy metals in farmland soil around the mining area during the years of mining, beneficiation and processing. It is particularly necessary to study the heavy metal pollution in soil, find out the impact of mining activities on heavy metals in surrounding farmland soil, and provide a scientific basis for prevention and control of heavy metal pollution in farmland soil. OBJECTIVES To clearly understand the impact of mining activities in the western Henan mining area on heavy metals in the surrounding farmland soil, provide necessary basic data for supporting the safe production of key mineral resources, the surrounding agricultural safety, and prevent and control heavy metal pollution in farmland soil. METHODS 375 topsoil samples from the farmland around the western Henan gold mining area at a depth of 0-20cm were systematically investigated and analyzed with reference to Code of Practice for Soil Geochemical Survey (DZ/T 0145—2017). The contents and spatial distribution characteristics of Cd, Cu, Zn, Pb, Hg, As, Cr, Ni were analyzed. The heavy metal pollution and ecological risk were evaluated by the geo-accumulation index method and potential ecological risk index method. RESULTS (1) The contents variation range of Cu, Pb, Zn, Ni, As, Hg, Cd, Cr are 1.00-71.72, 2.00-524.79, 8.00-320.37, 2.00-52.77, 2.29-24.64, 0.0067-0.268, 0.04-1.30, 28.20-107.93, respectively, and the average are 35.33, 74.43, 137.69, 31.60, 12.39, 0.064, 0.43, 76.27, respectively, showing significant differences between the 8 heavy metals. Compared with the soil background value in the middle reaches of the Yellow River, the average contents of Cu, Pb, Zn, Ni, As, Hg, Cd, Cr are 1.47, 3.24, 2.06, 1.05, 1.03, 1.52, 2.77 and 1.07 times of them, respectively, but lower than the value of risk screening values for soil contamination of agricultural land.(2) The characteristics of coefficients of variation show that Pb(90.72%)>Hg(85.25%)>Cd(65.65%)>Zn(44.0%)>Cu(33.66%)>As(31.72%)>Ni(24.23%)>Cr(13.61%), the Pb, Hg, Cd are the primary factors causing the soil pollution as the external input by mineral activities for the high coefficients of variation and special relation with mining. The main ore-forming elements in the gold deposit area are Au and Mo, and the associated elements are Cu, Pb, Zn, Ni, As, Hg, Cd, which may diffuse into the surrounding environment during ore transportation, waste rock and slag piling along the river, and processing. Alongside the Daping River, the two gold mining areas and concentrators are distributed around the farmland, and the gold ore heap leaching site on the east side is located at the top of the hillside and hill. The heavy metals produced by mining activities can diffuse in the downstream agricultural areas through atmospheric deposition, rainwater leaching, river drainage, and can accumulate in the surrounding agricultural soil, causing heavy metal pollution in the agricultural soil around the mining area.(3) The geo-accumulation index of 8 heavy metals is -0.1, 0.74, 0.33, -0.56, -0.60, -0.29, 0.62, -0.49 with the order Pb>Cd>Zn>Cu>Hg>Cr>Ni>As, in which Cu, Hg, Cr, Ni, As show no influence to the quality of soils for the average geo-accumulation index lower than 0, and Pb, Cd, Zn show moderate pollution for the average geo-accumulation index between 0-1. Among them, the proportion of samples with a Cd element of medium or higher impact grade is 20.27%, the proportion of samples with medium to strong impact grade is 7.73%, and the proportion of samples with strong impact grade is 1.07%. The proportion of samples with a Pb element above the moderate impact level is 18.93%, and the proportion of samples with moderate to strong impact level is 10.40%. Hg and Zn also have 7.46% and 13.33% of the samples reaching the moderate impact level, indicating that Hg, Cd and Pb in the soil at local sampling sites have different degrees of impact on farmland soil quality.(4) The average value of the single-factor potential ecological risk index of eight heavy metals is between 2.06 and 83.62, among which the single-factor potential ecological risk index of As, Cr, Ni, Cu and Zn is a slight potential ecological risk. Pb is mainly subject to slight potential ecological risks for 92% of samples, moderate potential ecological risks for 7.47% of samples and strong potential ecological risks for 0.53% of samples. Cd is dominated by moderate potential ecological risks, with 46.14% of samples, and there are 25.33% and 10.93% of samples reaching strong and very strong potential ecological risks respectively. For the ecological risk index of Hg, there are 35.47%, 11.46%, 4.27% and 3.20% of the samples that reach moderate, strong, very strong and very strong degree. The comprehensive potential ecological risk index (RI) ranges from 51.66 to 689.64, with an average of 192.07. The proportion of samples with slight, moderate, strong and very strong impact degree is 46.40%, 41.07%, 11.20% and 1.33%, respectively. The overall comprehensive potential ecological risk index shows moderate potential ecological risks. CONCLUSIONS Compared with the risk screening values for soil contamination of agricultural land, the contents of Cd, Cu, Zn, Pb, Cr, Ni, As, Hg are all lower than the standard, indicating low risk for the soil environment. There were different degrees of accumulation surrounding the intense mining area of Cd, Pb, and Zn by longtime mineral development. Cu, Ni, As, Hg, and Cr were influenced by the natural factor. The farmland area with strong and very strong comprehensive potential ecological risks is 349.4 hectares and 11.71 hectares, respectively. Cd and Hg are the main contributing elements, with higher risk to the soil ecology, which should be monitored and controlled from source to avoid the further accumulation of heavy metal elements in the soil.

Devang Falor, Bishakhdatta Gayen, Bishakhdatta Gayen et al.

The upper ocean surface layer is directly affected by the air-sea fluxes. The diurnal variations in these fluxes also cause the upper ocean mixed layer turbulence and mixing to diurnally vary. The underlying thermohaline structure also varies accordingly throughout the day. Here we use large-eddy simulation to quantify the role of surface evaporation in modulating the diurnal mixed layer turbulence and mixing in the presence of wind forcing. During daytime, the upper ocean boundary layer becomes thermally stratified, and a salinity inversion layer is formed in the upper 10m, leading to double diffusive salt-fingering instability. During nighttime, the mixed layer undergoes convective deepening due to surface buoyancy loss redfrom both surface cooling and evaporation. We find that salinity makes a major contribution to the convective instability during both transitions between day and night. Overall surface evaporation increases the mixed layer depth and irreversible mixing through convection, both during nighttime and daytime, and leads to better prediction of the dynamical variables as sea surface salinity (SSS) and sea surface temperature (SST). Our findings can help improve the ocean parameterizations to improve the forecasts on a diurnal timescale.

Tong Zhang, Yong Liu, Boyang Li et al.

With the evolution of pre-trained language models, current open-domain dialogue systems have achieved great progress in conducting one-session conversations. In contrast, Multi-Session Conversation (MSC), which consists of multiple sessions over a long term with the same user, is under-investigated. In this paper, we propose History-Aware Hierarchical Transformer (HAHT) for multi-session open-domain dialogue. HAHT maintains a long-term memory of history conversations and utilizes history information to understand current conversation context and generate well-informed and context-relevant responses. Specifically, HAHT first encodes history conversation sessions hierarchically into a history memory. Then, HAHT leverages historical information to facilitate the understanding of the current conversation context by encoding the history memory together with the current context with attention-based mechanisms. Finally, to explicitly utilize historical information, HAHT uses a history-aware response generator that switches between a generic vocabulary and a history-aware vocabulary. Experimental results on a large-scale MSC dataset suggest that the proposed HAHT model consistently outperforms baseline models. Human evaluation results support that HAHT generates more human-like, context-relevant and history-relevant responses than baseline models.

Juma J. Kegamba, Kamaljit K. Sangha, Penelope Wurm et al.

Benefit-sharing has been instrumental in empowering local communities living on the edge of protected areas to engage in natural resource management and enhance biodiversity conservation outcomes. Tanzania has various categories of protected area managed by six main conservation institutions, each with different types of benefit-sharing mechanisms. To investigate the acceptability of these mechanisms among local communities living in proximity to protected areas and their effectiveness at delivering benefits, we undertook a systematic review of > 1000 peer-reviewed articles related to the topic published between January 1990 and February 2021. The 71 publications that met our selection criteria covered all the main categories of protected area in Tanzania. Benefit-sharing mechanisms took three forms: i. social services provision; ii. livelihood provision; and iii. employment for local people. About half the studies (48%) indicated that local people accepted or strongly accepted the benefits provided by conservation institutions in Tanzania with the level of community acceptance linked strongly with the history of engagement between communities and the conservation institutions while 40% of the reviewed studies indicated the negative views. We recommend that future research explores the values and demand for benefits among local people living close to protected areas, particularly in disaffected communities, to ensure benefit-sharing mechanisms deliver desirable socio-economic outcomes for local communities as well as conservation outcomes.

Da Huo, Da Huo, Da Huo et al.

Danko Georgiev, Eliahu Cohen

Quantum entanglement is a key resource, which grants quantum systems the ability to accomplish tasks that are classically impossible. Here, we apply Feynman's sum-over-histories formalism to interacting bipartite quantum systems and introduce entanglement measures for bipartite quantum histories. Based on the Schmidt decomposition of the matrix comprised of the Feynman propagator complex coefficients, we prove that bipartite quantum histories are entangled if and only if the Schmidt rank of this matrix is larger than 1. The proposed approach highlights the utility of using a separable basis for constructing the bipartite quantum histories and allows for quantification of their entanglement from the complete set of experimentally measured sequential weak values. We then illustrate the non-classical nature of entangled histories with the use of Hardy's overlapping interferometers and explain why local hidden variable theories are unable to correctly reproduce all observable quantum outcomes. Our theoretical results elucidate how the composite tensor product structure of multipartite quantum systems is naturally extended across time and clarify the difference between quantum histories viewed as projection operators in the history Hilbert space or viewed as chain operators and propagators in the standard Hilbert space.

Pierre-Louis Guhur, Shizhe Chen, Ricardo Garcia et al.

In human environments, robots are expected to accomplish a variety of manipulation tasks given simple natural language instructions. Yet, robotic manipulation is extremely challenging as it requires fine-grained motor control, long-term memory as well as generalization to previously unseen tasks and environments. To address these challenges, we propose a unified transformer-based approach that takes into account multiple inputs. In particular, our transformer architecture integrates (i) natural language instructions and (ii) multi-view scene observations while (iii) keeping track of the full history of observations and actions. Such an approach enables learning dependencies between history and instructions and improves manipulation precision using multiple views. We evaluate our method on the challenging RLBench benchmark and on a real-world robot. Notably, our approach scales to 74 diverse RLBench tasks and outperforms the state of the art. We also address instruction-conditioned tasks and demonstrate excellent generalization to previously unseen variations.

Ke Tran Dinh, Thang Nguyen Nhu

We are concerned with the initial value problem governed by generalized Rayleigh-Stokes equations, where the nonlinearity depends on history states and takes values in Hilbert scales of negative order. The solvability and Hölder regularity of solutions are proved by using fixed point arguments and embeddings of fractional Sobolev spaces. An application to a related inverse source problem is given.

Federico Riva, Stefano Mammola

Abstract Measuring commonness and rarity is pivotal to ecology and conservation. Zeta diversity, the average number of species shared by multiple sets of assemblages, and Dark diversity, the number of species that could occur in an assemblage but are missing, have been recently proposed to capture two aspects of the commonness‐rarity spectrum. Despite a shared focus on commonness and rarity, thus far, Zeta and Dark diversities have been assessed separately. Here, we review these two frameworks and suggest their integration into a unified paradigm of the “rarity facets of biodiversity.” This can be achieved by partitioning Alpha and Beta diversities into five components (the Zeta, Eta, Theta, Iota, and Kappa rarity facets) defined based on the commonness and rarity of species. Each facet is assessed in traditional and multiassemblage fashions to bridge conceptual differences between Dark diversity and Zeta diversity. We discuss applications of the rarity facets including comparing the taxonomic, functional, and phylogenetic diversity of rare and common species, or measuring species' prevalence in different facets as a metric of species rarity. The rarity facets integrate two emergent paradigms in biodiversity science to better understand the ecology of commonness and rarity, an important endeavor in a time of widespread changes in biodiversity across the Earth.

Christian Frevel

The paper addresses two crucial questions of the history of Israelite religion. Did YHWH emerge in the southern steppe and when did YHWH become the God of Judah? After discussing the available evidence for YHWH’s origin in the South, the paper tests the extra-biblical evidence for the worship of YHWH in Israel and Judah and questions his widespread importance in the tenth and early ninth centuries BCE in the mentioned territories. By presenting the theophoric personal names, the hypothesis is corroborated that YHWH was significantly introduced at the earliest by the Omrides. Moving then to the epigraphic evidence, the additional evince for YHWH’s origin in the South is reviewed negatively. YHWH of Teman from Kuntillet ʽAjrud cannot prove the origin of this deity in the South. It is rather a piece of evidence that the worship of this deity in the South was not natural even in the mid-eighth century BCE. That YHWH’s true origin is in Midian, Paran, Seir, etc. remains a speculative hypothesis that is built on the tradition-history of some biblical passages and the biblical Sinai tradition. This particular feature is indeed related to the South and its struggle to claim independence for the Southern YHWH from the North. YHWH was only introduced to Judah as a patron deity of the dynasty, and that is the state of the Omrides ruling in Jerusalem.

Vreni Häussermann, Vreni Häussermann, Stacy Anushka Ballyram et al.

Deep-water emergence (DWE) is the phenomenon where marine species normally found at great depths (i.e., below 200 m), can be found locally occurring in significantly shallower depths (i.e., euphotic zone, usually shallower than 50 m). Although this phenomenon has been previously mentioned and deep-water emergent species have been described from the fjord regions of North America, Scandinavia, and New Zealand, local or global hypotheses to explain this phenomenon have rarely been tested. This publication includes the first literature review on DWE. Our knowledge of distribution patterns of Chilean marine invertebrates is still very scarce, especially from habitats below SCUBA diving depth. In our databases, we have been gathering occurrence data of more than 1000 invertebrate species along the Chilean coast, both from our research and from the literature. We also distributed a list of 50 common and easily in situ-identifiable species among biologically experienced sport divers along the Chilean coast and recorded their sighting reports. Among other findings, the analysis of the data revealed patterns from 28 species and six genera with similar longitudinal and bathymetric distribution along the entire Chilean coast: along the Chilean coast these species are typically restricted to deep water (>200 m) but only in some parts of Chilean Patagonia (>39°S–56°S), the same species are also common to locally abundant at diving depths (<30 m). We found 28 of these ‘deep’ species present in shallow-water of North Patagonia, 32 in Central Patagonia and 12 in South Patagonia. The species belong to the phyla Cnidaria (six species), Mollusca (four species), Arthropoda (two species) and Echinodermata (16 species). We ran several analyses comparing depth distribution between biogeographic regions (two-way ANOVA) and comparing abiotic parameters of shallow and deep sites to search for correlations of distribution with environmental variables (Generalized Linear Models). For the analyses, we used a total of 3328 presence points and 10635 absence points. The results of the statistical analysis of the parameters used, however, did not reveal conclusive results. We summarize cases from other fjord regions and discuss hypotheses of DWE from the literature for Chilean Patagonia.

John Mraz

This article explores the importance of photographic archives (fototecas) in preserving the sources with which to create a national visual history and identity. It charts the arc from imperial photography of Mexico, lodged in European and U.S. archives, to the development of Mexican institutions dedicated to the preservation of the photographic patrimony. Particular attention is paid to the photography of indigenous peoples by foreigners and Mexicans, and the location of the archives in which that imagery is held. Some of the archives mentioned are found in Mexico: Archivo General de la Nación, the Fototeca Nacional-Instituto Nacional de Antropología e Historia (INAH), the Museo Nacional, and the Instituto Nacional de los Pueblos Indígenas (INPI). Others are located elsewhere: the Smithsonian Institute, the Getty Museum, the Musée du Quai Branly-Jacques Chirac, American Museum of Natural History, and the Museum of Cultural History in Oslo. Among the photographers mentioned are: Desiré Charnay, León Diguet, Teoberto Maler, Frederick Starr, Carl Lumholtz, Julio de la Fuente, and Nacho López.

Somil Gupta, Neeraj Sharma

The rise of intelligent assistant systems like Siri and Alexa have led to the emergence of Conversational Search, a research track of Information Retrieval (IR) that involves interactive and iterative information-seeking user-system dialog. Recently released OR-QuAC and TCAsT19 datasets narrow their research focus on the retrieval aspect of conversational search i.e. fetching the relevant documents (passages) from a large collection using the conversational search history. Currently proposed models for these datasets incorporate history in retrieval by appending the last N turns to the current question before encoding. We propose to use another history selection approach that dynamically selects and weighs history turns using the attention mechanism for question embedding. The novelty of our approach lies in experimenting with soft attention-based history selection approach in an open-retrieval setting.

Gabriel Can-Hernández, Claudia Villanueva-García, Elías José Gordillo-Chávez et al.

Human–wildlife conflicts occur when wildlife has an adverse effect on human activities (e.g., predation of livestock, crop raiding). These conflicts are increasing, particularly in areas surrounding natural protected areas, where villagers engage in subsistence agriculture. Crop damage may cause farmers to retaliate and harm wildlife species considered responsible for the damage. Among the factors that determine the intensity of the conflict are the frequency of the damage and the amount of biomass consumed relative to the perceptions, values, and cultural history of the farmers affected. To better understand the conflicts between farmers and wildlife, we compared farmer perceptions of wildlife damage to corn (Zea mays) to damage estimates recorded from May to June 2016 in 2 communities located in southern Mexico adjacent to the Natural Protected Area of Agua Blanca. We identified 128 farmers who had reported previous damage and used an administered structured questionnaire to assess their perceptions of the magnitude of the damage. Over 70% of the farmers surveyed considered that wildlife incursions in crops are a problem and 18% of them had implemented hunting and poisoning as a control measure. Farmers attributed their losses mainly to white-nosed coati (Nasua narica) and northern raccoon (Procyon lotor). However, our field data indicated that birds were causing more damage. On average, each corn crop lost $30.80; this value may be considered low, but the farmers’ dependence on the harvest they obtain from their crops causes these losses, added to those they already have due to other causes (i.e., long droughts, insect pests, and fungus), which impact their bottom line. Wildlife crop depredation is not the main cause of economic loss, but its impact negatively influences the perception of some farmers on wildlife. A poor perception in farmers could lead to an increase in the use of lethal methods, which may also affect nontargets.

Katie Wilson, Jon Wakefield

BACKGROUND There is an increasing demand for high quality subnational estimates of under-five mortality. In low and middle income countries, where the burden of under-five mortality is concentrated, vital registration is often lacking and household surveys, which provide full birth history data, are often the most reliable source. Unfortunately, these data are spatially sparse and so data are pulled from other sources to increase the available information. Summary birth histories represent a large fraction of the available data, and provide numbers of births and deaths aggregated over time, along with the mother's age. OBJECTIVE Specialized methods are needed to leverage this information, and previously the Brass method, and variants, have been used. We wish to develop a model-based approach that can propagate errors, and make the most efficient use of the data. Further, we strive to provide a method that does not have large computational overhead. CONTRIBUTION We describe a computationally efficient model-based approach which allows summary birth history and full birth history data to be combined into analyses of under-five mortality in a natural way. The method is based on fertility and mortality models that allow direct smoothing over time and space, with the possibility for including relevant covariates that are associated with fertility and/or mortality. We first examine the behavior of the approach on simulated data, before applying the model to survey and census data from Malawi.

Tomohiro Nakama

Gravitational-wave detectors on earth have detected gravitational waves from merging compact objects in the local Universe. In future we will detect gravitational waves from higher-redshift sources, which trace the high-redshift structure formation history. That is, by observing high-redshift gravitational-wave events we will be able to probe structure formation history. This will provide additional insight into the early Universe when primordial fluctuations are generated and also into the nature of dark matter.