Time Diversity Research Articles

Learning Harris Hawk Algorithm Based on Signal-to-Noise Ratio

In view of the problem of insufficient population learning and adaptability of the Harris Hawk optimization algorithm, this paper proposes a learning Harris Hawk algorithm based on signal-to-noise ratio, referred to as SLHHO. This algorithm introduces the concept of signal-to-noise ratio to determine the location information of individuals, and designs a coordinated learning strategy that can more reasonably update the location of individuals within the population, and then redesign the escape distance to improve the adaptation and optimization of the algorithm. ability. Using 12 benchmark functions as standards, the performance of this algorithm was tested with variants of the Harris Eagle algorithm and other algorithms, and comparative analysis was conducted in evaluation indicators such as time complexity, diversity, exploration and development, and the results show that SLHHO has strong competitiveness and feasibility. Finally, the practicality of SLHHO was verified in the pressure vessel design problem.

Unveiling the Genome-Wide Consequences of Range Expansion and Mating System Transitions in Primula vulgaris.

Genetic diversity is heterogeneously distributed among populations of the same species, due to the joint effects of multiple demographic processes, including range contractions and expansions, and mating systems shifts. Here, we ask how both processes shape genomic diversity in space and time in the classical Primula vulgaris model. This perennial herb originated in the Caucasus region and was hypothesized to have expanded westward following glacial retreat in the Quaternary. Moreover, this species is a long-standing model for mating system transitions, exemplified by shifts from heterostyly to homostyly. Leveraging a high-quality reference genome of the closely related Primula veris and whole-genome resequencing data from both heterostylous and homostylous individuals from populations encompassing a wide distribution of P. vulgaris, we reconstructed the demographic history of P. vulgaris. Results are compatible with the previously proposed hypothesis of range expansion from the Caucasus region approximately 79,000 years ago and suggest later shifts to homostyly following rather than preceding postglacial colonization of England. Furthermore, in accordance with population genetic theoretical predictions, both processes are associated with reduced genetic diversity, increased linkage disequilibrium, and reduced efficacy of purifying selection. A novel result concerns the contrasting effects of range expansion versus shift to homostyly on transposable elements, for the former, process is associated with changes in transposable element genomic content, while the latter is not. Jointly, our results elucidate how the interactions among range expansion, transitions to selfing, and Quaternary climatic oscillations shape plant evolution.

Adaptive support vector machine for time-variant failure probability function estimation

Time variant reliability analysis introduces additional complexity due to the inclusion of time. When the time-variant failure probability function (TFPF) of the structure is of interest, it inherently involves sequential evaluations of the failure probabilities of series systems varied with time in discretized space, posing a challenge to reliability analysis. An efficient approach for the evaluation of the TFPF, called ‘Time-dependent Adaptive Support Vector Machine combined with Monte Carlo Simulation’ (TASVM-MCS), is presented to reduce the corresponding computational cost. Based on the samples from Monte Carlo simulation (MCS), an iterative strategy is proposed to actively extract the most valuable sample points from the sample pool and iteratively update the support vector machine (SVM) model. In particular, an active learning function is proposed to take into account the diversity of samples and time simultaneously. In this way, the built SVM will be more suitable for the evaluation of TFPF other than a point-wise failure probability. The proposed TASVM-MCS method is relatively less sensitive to the dimensionality of the input variables, making it a powerful and promising approach for time-variant reliability computations. Four representative examples are given to demonstrate the significant effectiveness and efficiency of the proposed method.

Influence of telecommuting on out-of-home time use and diversity of locations visited: Evidence from the COVID-19 pandemic

The COVID-19 pandemic has led to unforeseen changes in travel and activity behavior, most notably the wide adoption of telecommuting across various sectors of the workforce. This paper investigates the impact of telecommuting on time use and the number of unique locations visited, both of which have been shown to be closely linked to well-being. Previous telecommuting research often relies on cross-sectional data for which it is difficult to control for unobserved confounding, only analyzes impacts of time-use at the daily level, and has yet to quantify the impact of telecommuting on diversity of locations visited. We use quasi-experimental designs to control for unobserved confounders and extend previous research to identify whether the daily impacts of telecommuting on time-use are additive or substitutional at the weekly level. We use passively collected Point of Interest (POI) data between January 2020 and September 2022, supplemented by five waves of survey responses throughout the COVID-19 pandemic (August 2020, October 2020, December 2020, April 2021, and July 2021) from a panel of U.S. smartphone users. We find that on telecommuting days, workers spend significantly more time at out-of-home non-work locations, estimated to be 114 min prior to the COVID-19 pandemic, decreasing in the early stages of the pandemic to 63 min, and recovering to approximately 120 min in 2022, estimates that are within the range of estimates presented in previous literature. While existing literature focuses on single day analyses, our weekly analysis suggests that daily differences due to telecommuting are substitutional, with the effect of an additional day of telecommuting on time-use at the weekly level being null. Our extension to analyze the impacts of telecommuting on the number of unique locations visited shows that an additional day of telecommuting results in an average decrease of 0.35 in the number of unique weekly locations visited. Collectively, our findings suggest that while telecommuting does not diminish the overall weekly time spent at out-of-home non-work locations, it decreases the diversity of such locations on a weekly level.

Personalization of User Experience in Language Learning through Large Language Model Assistants

Language learning benefits from a comprehensive approach, but traditional software often lacks personalization. This study analyzes prompt engineering principles to implement a test generation algorithm using Large Language Models (LLMs). The approach involved examining these principles, exploring related strategies, and creating a unified prompt structure. A test generation script was developed and integrated into an API for an interactive language learning platform. While LLM integration offers highly effective, personalized learning experiences, issues like response time and content diversity need addressing. Future advancements in LLM technology are expected to resolve these limitations.

Top management team gender diversity and power dynamics in times of change

Abstract Extant research examining the effects of top management team (TMT) gender diversity on firm performance report equivocal findings. We seek to enhance understanding of this critical relationship in the context of an acquisition, which necessitates changes in one or both firms during a process characterized by non-routine decisions, time pressures, high uncertainty, and frequent debates among strategic leaders. Specifically, we examine the effects of gender diversity of top management and female executives’ formal and informal power on post-deal performance. Our results indicate gender diversity has negative effects on post-deal performance. Further, in a subsample of acquirers with gender diverse teams, our results reveal that female executives’ structural power and ownership power have negative performance effects, while power conferred through an elite education has positive performance effects. Our findings highlight the need to expand gender diversity research to consider the strategic context facing diverse TMTs and power dynamics among them.

Genetic variation in phenology of wild Arabidopsis thaliana plants.

Phenology and the timing of development are often under selection, but at the same time influence selection on other traits by controlling how traits are expressed across seasons. Plants often exhibit high natural genetic variation in phenology when grown in controlled environments, and many genetic and molecular mechanisms underlying phenology have been dissected. There remains considerable diversity of germination and flowering time within populations in the wild and the contribution of genetics to phenological variation of wild plants is largely unknown. We obtained collection dates of naturally inbred Arabidopsis thaliana accessions from nature and compared them to experimental data on the descendant inbred lines that we synthesized from two new and 155 published controlled experiments. We tested whether the genetic variation in flowering and germination timing from experiments predicted the phenology of the same inbred lines in nature. We found that genetic variation in phenology from controlled experiments significantly, but weakly, predicts day of collection from the wild, even when measuring collection date with accumulated photothermal units. We found that experimental flowering time breeding values were correlated to wild flowering time at location of origin estimated from herbarium collections. However, local variation in collection dates within a region was not explained by genetic variation in experiments, suggesting high plasticity across small-scale environmental gradients. This apparent low heritability in natural populations may suggest strong selection or many generations are required for phenological adaptation and the emergence of genetic clines in phenology.

Design and Investigation of a 10 Gb/s Hybrid Spatial-time Diversity FSO-CDMA Communication System

Abstract This paper presents a novel strategy for free space optical (FSO) communication system that combines hybrid spatial-time diversity and optical code division multiple access (OCDMA). The authors demonstrate a 10 Gb/s hybrid spatial-time diversity FSO-CDMA experimental system for the first time. They investigate the bit error rate (BER) and physical-layer security under weak and strong turbulence conditions. The experimental results demonstrate that the proposed scheme can improve the performance of the FSO-CDMA system. In the hybrid spatial-time diversity FSO-CDMA system, the BER of the eavesdropper (Eve) exceeds the hard-decision forward-error-correction threshold of 3.8E-3. It is also worth noting that Eve can intercept and recover data without a matched decoder in a spatial diversity FSO-CDMA system. As a result, the proposed scheme can simultaneously enhance reliability and physical-layer security compared to time or spatial diversity systems.

Ediacaran diversity in space and time

The Ediacaran Subcommission of the International Commission on Stratigraphy is diligently working toward the goal of subdividing the Ediacaran Period into precise and useful chronostratigraphic units. As emphasized by Xiao and colleagues in 2016, one of the most effective tools in this endeavor will be the use of index fossils. Our special issue serves as a presentation of ongoing research efforts aimed at advancing this task and contains explorations into taxonomy, taphonomy, and the diversity of life during the Ediacaran Period.

Lateral connectivity maintains higher freshwater mussel biodiversity

Abstract The loss of lateral hydrological connectivity (LLHC) in freshwater ecosystems is increasingly threatening biodiversity; however, studies reporting this situation are limited, especially those assessing multi‐measure biodiversity features at large spatial scales. Here, and using one the most threatened taxonomic groups in freshwater ecosystems, we examined the possible influence of LLHC on the species diversity, density, and biomass of mussel assemblages and the genetic diversity and structure of Nodularia douglasiae (a common and widespread native species) in the Yangtze River floodplain. Results showed that the species diversity of freshwater mussels (α and β diversity) significantly differed between the connected and the disconnected areas, with higher α diversity and lower β diversity in the connected areas. At the same time, relative abundance, density, biomass, and genetic diversity of freshwater mussels were higher in the connected areas. High genetic differentiation and low gene flow were found among the 18 analysed N. douglasiae populations, indicating that LLHC is affecting genetic structure of this particular freshwater mussel species. Overall, results indicated that river–lake connectivity is affecting freshwater mussel biodiversity. In addition, this study highlights that multi‐measure biodiversity features provide distinct information about biodiversity dynamics, and are essential to evaluate the effects of floodplain disconnection. We advocate that an integrative approach to floodplain management embracing species and genetic diversity is needed for effective biodiversity conservation in large river ecosystems.

Diversity and multiplicity in uncertain times: the category of “difficult knowledge” in the sensitive contexts of education and social research

This article explores the category of “difficult knowledge” within the sensitive contexts of education and social research amidst contemporary global transformations. Uncertain times marked by humanitarian crises, wars, migration, and socio-economic shifts challenge the stability and security of societies. Difficult knowledge encompasses emotionally charged, complex topics integral to social, political, and educational spheres, compelling individuals and groups to confront uncomfortable truths and deconstruct human understanding. This concept, introduced by Britzman (1998), addresses the cognitive and emotional struggles in engaging with traumatic representations of historical and social events. The paper highlights the necessity for educators and researchers to navigate these challenges, fostering critical and reflective analyses while managing their psychological impacts. It underscores the dual role of researchers as both empathetic human beings and objective professionals, particularly in extreme field conditions. Additionally, it discusses the implications of conspiracy theories as a form of difficult knowledge, emphasizing the need for educational strategies that promote critical thinking and resilience. The article calls for greater attention to the sensitivities of the research process and the ethical responsibilities in studying and teaching difficult knowledge.

Natural variation of domestication-related genes contributed to latitudinal expansion and adaptation in soybean

Soybean is a major source of protein and edible oil worldwide. Originating from the Huang-Huai-Hai region, which has a temperate climate, soybean has adapted to a wide latitudinal gradient across China. However, the genetic mechanisms responsible for the widespread latitudinal adaptation in soybean, as well as the genetic basis, adaptive differentiation, and evolutionary implications of theses natural alleles, are currently lacking in comprehensive understanding. In this study, we examined the genetic variations of fourteen major gene loci controlling flowering and maturity in 103 wild species, 1048 landraces, and 1747 cultivated species. We found that E1, E3, FT2a, J, Tof11, Tof16, and Tof18 were favoured during soybean improvement and selection, which explained 75.5% of the flowering time phenotypic variation. These genetic variation was significantly associated with differences in latitude via the LFMM algorithm. Haplotype network and geographic distribution analysis suggested that gene combinations were associated with flowering time diversity contributed to the expansion of soybean, with more HapA clustering together when soybean moved to latitudes beyond 35°N. The geographical evolution model was developed to accurately predict the suitable planting zone for soybean varieties. Collectively, by integrating knowledge from genomics and haplotype classification, it was revealed that distinct gene combinations improve the adaptation of cultivated soybeans to different latitudes. This study provides insight into the genetic basis underlying the environmental adaptation of soybean accessions, which could contribute to a better understanding of the domestication history of soybean and facilitate soybean climate-smart molecular breeding for various environments.

Do community changes persist after irruptive population dynamics? A case study from an invasive species boom and bust.

Irruptive or boom-and-bust population dynamics, also known as 'outbreaks', are an important phenomenon that has been noted in biological invasions at least since Charles Elton's classic book was published in 1958. Community-level consequences of irruptive dynamics are poorly documented and invasive species provide excellent systems for their study. African Jewelfish (Rubricatochromis letourneuxi, "jewelfish") are omnivores that demonstrate opportunistic carnivory, first reported in Florida in the 1960s and in Everglades National Park (ENP) in 2000. Twelve years after invasion in ENP, jewelfish underwent a 25-fold increase in density in one year. By 2016, jewelfish represented 25-50% of fish biomass. Using a 43-year fish community dataset at two sites (1978-2021), and a 25-year dataset of fish and invertebrate communities from the same drainage (1996-2021), with additional spatial coverage, we quantified differences in fish and invertebrate communities during different phases of invasion. During jewelfish boom, abundant, native cyprinodontiform fishes decreased in density and drove changes in community structure as measured by similarity of relativized abundance. Density of two species declined by > 70%, while four declined by 50-62%. Following the jewelfish bust, some species recovered to pre-boom densities while others did not. Diversity of recovery times produced altered community structure that lagged for at least four years after the jewelfish population declined. Community structure is an index of ecological functions such as resilience, productivity, and species interaction webs; therefore, these results demonstrate that irruptive population dynamics can alter ecological functions of ecosystems mediated by community structure for years following that population's decline.

Estimating Increased Transient Water Storage with Increases in Beaver Dam Activity

Dam building by beaver (Castor spp.) slows water movement through montane valleys, increasing transient water storage and the diversity of residence times. In some cases, water storage created by beaver dam construction is correlated to changes in streamflow magnitude and timing. However, the total amount of additional surface and groundwater storage that beaver dams may create (and, thus, their maximum potential impact on streamflow) has not been contextualized in the water balance of larger river basins. We estimate the potential transient water storage increases that could be created at 5, 25, 50, and 100% of maximum modeled beaver dam capacity in the Bear River basin, USA, by adapting the height above nearest drainage (HAND) algorithm to spatially estimate surface water storage. Surface water storage estimates were combined with the MODFLOW groundwater model to estimate potential increases in groundwater storage throughout the basin. We tested four scenarios to estimate potential transient water storage increases resulting from the construction of 1179 to 34,897 beaver dams, and estimated surface water storage to range from 57.5 to 72.8 m3 per dam and groundwater storage to range from 182.2 to 313.3 m3 per dam. Overall, we estimate that beaver dam construction could increase transient water storage by up to 10.38 million m3 in the Bear River basin. We further contextualize beaver dam-related water storage increases with streamflow, reservoir, and snowpack volumes.

Evolution of FLOWERING LOCUS T-like genes in angiosperms: a core Lamiales-specific diversification.

Plant life history is determined by two transitions, germination and flowering time, in which the phosphatidylethanolamine-binding proteins (PEBPs) FLOWERING LOCUS T (FT) and TERMINAL FLOWER1 (TFL1) play key regulatory roles. Compared with the highly conserved TFL1-like genes, FT-like genes vary significantly in copy numbers in gymnosperms, and monocots within the angiosperms, while sporadic duplications can be observed in eudicots. Here, via a systematic analysis of the PEBPs in angiosperms with a special focus on 12 representative species featuring high-quality genomes in the order Lamiales, we identified a successive lineage-specific but systematic expansion of FT-like genes in the families of core Lamiales. The first expansion event generated FT1-like genes mainly via a core Lamiales-specific whole-genome duplication (cL-WGD), while a likely random duplication produced the FT2-like genes in the lineages containing Scrophulariaceae and the rest of the core Lamiales. Both FT1- and FT2-like genes were further amplified tandemly in some families. These expanded FT-like genes featured highly diverged expression patterns and structural variation, indicating functional diversification. Intriguingly, some core Lamiales contained the relict MOTHER OF FT AND TFL1 like 2 (MFT2) that probably expanded in the common ancestor of angiosperms. Our data showcase the highly dynamic lineage-specific expansion of the FT-like genes, and thus provide important and fresh evolutionary insights into the gene regulatory network underpinning flowering time diversity in Lamiales and, more generally, in angiosperms.

Investigating eukaryotic and prokaryotic diversity and functional potential in the cold and alkaline ikaite columns in Greenland.

The ikaite columns in the Ikka Fjord, SW Greenland, represent a permanently cold and alkaline environment known to contain a rich bacterial diversity. 16S and 18S rRNA gene amplicon and metagenomic sequencing was used to investigate the microbial diversity in the columns and for the first time, the eukaryotic and archaeal diversity in ikaite columns were analyzed. The results showed a rich prokaryotic diversity that varied across columns as well as within each column. Seven different archaeal phyla were documented in multiple locations inside the columns. The columns also contained a rich eukaryotic diversity with 27 phyla representing microalgae, protists, fungi, and small animals. Based on metagenomic sequencing, 25 high-quality MAGs were assembled and analyzed for the presence of genes involved in cycling of nitrogen, sulfur, and phosphorous as well as genes encoding carbohydrate-active enzymes (CAZymes), showing a potentially very bioactive microbial community.

Typhoon disaster state information extraction for Chinese texts

Typhoon disasters undergo a complex evolutionary process influenced by temporal changes, and investigating this process constitutes the central focus of geographical research. As a key node within the typhoon disaster process, the state serves as the foundation for gauging the dynamics of the disaster. The majority of current approaches to disaster information extraction rely on event extraction methods to acquire fundamental elements, including disaster-causing factors, disaster-bearing bodies, disaster-pregnant environment and the extent of damage. Due to the dispersion of various disaster information and the diversity of time and space, it is a challenge for supporting the analysis of the typhoon disaster process. In this paper, a typhoon disaster state information extraction (TDSIE) method for Chinese texts is proposed, which aims to facilitate the systematic integration of fragmented typhoon disaster information. First, the integration of part-of-speech tagging with spatio-temporal information extraction is employed to achieve the tagging of typhoon disaster texts. Second, within the framework of spatio-temporal semantic units, the typhoon disaster semantic vector is constructed to facilitate the identification of information elements of typhoon disaster states. Third, co-referential state information fusion is performed based on spatio-temporal cues. Experimental analysis, conducted using online news as the data source, reveals that the TDSIE achieves precision and recall rates consistently surpassing 85%. The typhoon disaster state information derived from the TDSIE allows for the analysis of spatio-temporal patterns, evolutionary characteristics, and activity modes of typhoon disasters across various scales. Therefore, TDSIE serves as valuable support for investigating the inherent process properties of typhoon disasters.

A Deep Recommendation Model Considering the Impact of Time and Individual Diversity

A Deep Recommendation Model Considering the Impact of Time and Individual Diversity

Profile microsatellite mining of whole genome sequencing and transcriptomic assembly in dwarf and tall areca nut (Areca catechu) in Indonesia

Abstract. Romadhon MR, Sobir, Suwarno WB, Matra DD. 2024. Profile microsatellite mining of whole genome sequencing and transcriptomic assembly in dwarf and tall areca nut (Areca catechu L.) in Indonesia. Biodiversitas 25: 1081-1088. Areca nut (Areca catechu L.) has high diversity in fruit shape and flowering time. Two superior varieties are commonly cultivated in Indonesia, namely Betara areca nut (tall) and Emas areca nut (dwarf). Molecular level diversity from genomic and transcriptome of areca nut data is available at NCBI, but not yet for Indonesian areca nut. The research compared the results of SSR with two method approaches to detect genetic diversity in the plants accurately. This study aimed to compare the SSR motifs of Betara areca nut and Emas areca nut varieties from whole genome sequencing and transcriptome assembly. The research was conducted at the Leuwikopo Seed Centre Laboratory of the IPB University, Bogor, Indonesia. The methods used are Whole Genome Sequencing (WGS) and transcriptome assembly. A total number of identified SSRs from WGS approach from Betara areca nut of 95 SSRs and Emas areca nut of 95 SSRs, while Betara areca nut SSRs from transcriptome assembly of 466 SSRs and Emas areca nut of 357 SSRs. The percentage of contigs and transcripts from Betara areca nut containing SSR was 7.43% and 4.22%, respectively, while Emas areca nut was 8.06% and 2.04%, respectively. AT is the dominant SSR motif in WGS, while the GA motif dominates the transcriptome assembly results.

Uji Kinerja Alat Pencacah Rumput (Mini Chopper) Type TMB 01

The high amount of food crop production in East Lampung Regency produces abundant biomass. This biomass can be used as silage for animal feed. A grass chopper is needed to make silage. The aim of the research was to test the performance of the TMB 01 type grass chopper on corn stalks and elephant grass with engine rotation speeds of 800, 1000 and 1200 rpm. This research was carried out in June - November 2023, at the Self-Help Agricultural and Rural Training Center (P4S) Tani's Market Balerejo, East Lampung Regency. This research was carried out with observation parameters measuring chopping time, measuring machine rotation speed, measuring fuel consumption, measuring the diversity of biomass mass that had been chopped. The research results show that rotational speed (rpm) influences work capacity, working time, fuel consumption and chopping diversity. The best rotation speed of the shredding machine is 1200 rpm. Keywords: Biomass, Engine Revolution, Shredding Machine, Work Capacity.