population distribution
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2023 ◽  
Vol 83 ◽  
R. A. Khan ◽  
Z. Ullah ◽  
I. Uz Zaman ◽  
M. S. Khan ◽  
S. Mahmood ◽  

Abstract The Rufous treepie (Dendrocitta vagabunda) belongs to family corvidae, order Passeriformes which includes about 100 species. The current study was conducted to gather information about the Population distribution and habitat analysis of D. vagabunda at District Abbottabad, Pakistan. The data were collected on monthly basis both morning and evening times (2018-2019). “The ‘’Point count Method” was used for population estimation and ‘’Quadrates Method” for habitat analysis of study area. The result shows an average month-wise population density of D. vagabunda was maximum at Jhangra 0.14±0.039/ha, whereas minimum at Havelian 0.11±0.022/ha. There was no significant difference (p>0.05) among monthly population densities of D. vagabunda, however, a significant difference (p<0.05) was found between morning and evening times population of the specie. The present study revealed that importance value index (IVI) of plants species at Sherwan, Bakot, Havelian, Langra and Jhangra were 59.6±12.6, 50.1±6.9, 53.4±6.3, 66.8±10 and 60.1±7.7. Likewise, the frequency of shrubs at Sherwan, Bakot, Havelian, Langra and Jhangra were 33.3±4.2, 45±9.4, 46.7±8.2, 55.6±22.2 and 37.5±8.5. Similarly, the frequency of herbs at Sherwan, Bakot, Havelian, Langra and Jhangra were 40.4±6.0, 37.5±5.6, 53.3±7.4, 48.5±5.2 and 46.9±7.4 respectively. Our results show the study area as suitable habitat for D. vagabunda.

Econometrics ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 5
Ron Mittelhammer ◽  
George Judge ◽  
Miguel Henry

In this paper, we introduce a flexible and widely applicable nonparametric entropy-based testing procedure that can be used to assess the validity of simple hypotheses about a specific parametric population distribution. The testing methodology relies on the characteristic function of the population probability distribution being tested and is attractive in that, regardless of the null hypothesis being tested, it provides a unified framework for conducting such tests. The testing procedure is also computationally tractable and relatively straightforward to implement. In contrast to some alternative test statistics, the proposed entropy test is free from user-specified kernel and bandwidth choices, idiosyncratic and complex regularity conditions, and/or choices of evaluation grids. Several simulation exercises were performed to document the empirical performance of our proposed test, including a regression example that is illustrative of how, in some contexts, the approach can be applied to composite hypothesis-testing situations via data transformations. Overall, the testing procedure exhibits notable promise, exhibiting appreciable increasing power as sample size increases for a number of alternative distributions when contrasted with hypothesized null distributions. Possible general extensions of the approach to composite hypothesis-testing contexts, and directions for future work are also discussed.

PLoS ONE ◽  
2022 ◽  
Vol 17 (1) ◽  
pp. e0260326
Ricardo Antunes Dantas de Oliveira ◽  
Diego Ricardo Xavier Silva ◽  
Maurício Gonçalves e Silva

Snakebite accidents are considered category A neglected tropical diseases. Brazil stands out for snakebite accidents, mainly in the Amazon region. The best possible care after snakebite accidents is to obtain antiophidic sera on time. And the maximum ideal time to reach it is about 2 hours after an accident. Based on public health information and using a tool to analyze geographical accessibility, we evaluate the possibility of reaching Brazilian serum-providing health facilities from the relationship between population distribution and commuting time. In this exploratory descriptive study, the geographic accessibility of Brazilian population to health facilities that supply antiophidic serum is evaluated through a methodology that articulates several issues that influence the commuting time to health units (ACCESSMOD): population and facilities’ distribution, transportation network and means, relief and land use, which were obtained in Brazilian and international sources. The relative importance of the population without the possibility of reaching a facility in two hours is highlighted for Macro-Regions, States and municipalities. About nine million people live in locations more than two hours away from serum-providing facilities, with relevant variations between regions, states, and municipalities. States like Mato Grosso, Pará and Maranhão had the most important participation of population with reaching time problems to those units. The most significant gaps are found in areas with a dispersed population and sometimes characterized by a high incidence of snakebites, such as in the North of the country, especially in the Northeastern Pará state. Even using a 2010 population distribution information, because of the 2020 Census postponement, the tendencies and characteristics analyzed reveal challenging situations over the country. The growing availability of serum-providing health facilities, the enhanced possibilities of transporting accident victims, and even the availability of sera in other types of establishments are actions that would allow expanding the possibilities of access to serum supply.

Eric Tsz-Chun Poon ◽  
Grant Tomkinson ◽  
Wendy Yajun Huang ◽  
Stephen H.S. Wong

Low physical fitness in adolescence is linked with increased cardiometabolic risk and early all-cause mortality. This study aimed to estimate temporal trends in the physical fitness of Hong Kong adolescents aged 12–17 years between 1998 and 2015. Physical fitness (9-min run/walk, sit-ups, push-ups, and sit-and-reach) and body size data in a total of 28,059 adolescents tested across five population-representative surveys of Hong Kong secondary school pupils, were reported. Temporal trends in means were estimated at the gender-age level by best-fitting sample-weighted linear regression, with national trends estimated by a post-stratified population-weighting procedure. Overall, there were small declines in 9-min run/walk (effect size (ES) = 0.29 (95%CI: 0.32, 0.26)) and sit-ups performance (ES = 0.24 (95%CI: 0.27, 0.21)), with negligible changes in push-ups and sit-and-reach performance. There were small concurrent increases in both mean height and body mass, with a negligible increase in sum of skinfolds. Trends in mean physical fitness and body size/ were not always uniform across the population distribution. The small declines in mean 9-min run/walk and sit-ups performance for Hong Kong adolescents are suggestive of corresponding declines in cardiorespiratory fitness and abdominal/core endurance, respectively. Increased national health promotion strategies are required to improve existing fitness trends.

2022 ◽  
pp. 001316442110634
Patrick D. Manapat ◽  
Michael C. Edwards

When fitting unidimensional item response theory (IRT) models, the population distribution of the latent trait (θ) is often assumed to be normally distributed. However, some psychological theories would suggest a nonnormal θ. For example, some clinical traits (e.g., alcoholism, depression) are believed to follow a positively skewed distribution where the construct is low for most people, medium for some, and high for few. Failure to account for nonnormality may compromise the validity of inferences and conclusions. Although corrections have been developed to account for nonnormality, these methods can be computationally intensive and have not yet been widely adopted. Previous research has recommended implementing nonnormality corrections when θ is not “approximately normal.” This research focused on examining how far θ can deviate from normal before the normality assumption becomes untenable. Specifically, our goal was to identify the type(s) and degree(s) of nonnormality that result in unacceptable parameter recovery for the graded response model (GRM) and 2-parameter logistic model (2PLM).

Lin Dan ◽  
Hao Xu ◽  
Ping Guo ◽  
Jianye Zhao

Abstract Based on the proposed theoretical model of a three-level system, the optical Bloch equations including the direct two-photon transition (DTPT) process using the optical frequency comb (OFC) were derived and the population distribution of particles in the upper states varying with the velocity of the atoms was obtained. Comparing to the resonance two-photon transition process, that population was increased by a factor of 1.4 without the Doppler shift, which is consistent with our previous experimental results. Simultaneously, the relationship between momentum transfers, and atomic velocity and pulse number were analyzed. When applied to a multi-level system it was found the population of particles in the excited states increased by a few percentages. The novel approach of DTPT using OFC improved the utilization of comb teeth and atoms, increased the momentum transfer path, reduced the reachable Doppler temperature limit, and encouraged us to use OFC to cool multiple elements simultaneously through the DTPT process. By analyzing the Doppler temperature of 133Cs and 87Rb in one dimension, it was found that this process can lower a temperature below 100 mK and generate dipolar molecules 133Cs87Rb via photoassociation, which provides us a new tool to create dipolar molecules and to investigate their complex rovibrational spectra in ultra-cold chemistry.

2022 ◽  
Vol 25 (8) ◽  
pp. 831-838
R. B. Aitnazarov ◽  
T. M. Mishakova ◽  
N. S. Yudin

There are currently over a thousand indigenous cattle breeds well adapted to local habitat conditions thanks to their long history of evolution and breeding. Identification of the genetic variations controlling the adaptation of local cattle breeds for their further introduction into the genome of highly productive global breeds is a matter of great relevance. Studying individual populations of the same breed with the use of microsatellite markers makes it possible to assess their genetic diversity, relationships, and breed improvement potential. Although the Black Pied breed is the most common dairy cattle breed in Russia, there are only a few studies on genetic diversity in local Black Pied populations in some Russian regions. The goal of the present study was to analyze the genetic diversity in Black Pied cattle populations in the Novosibirsk Region and compare them with other Russian populations; to identify significantly divergent populations with a view to preserving them under the programs aimed at maintaining the genetic diversity of the domestic Black Pied breed. DNA samples from 4788 animals of the Black Pied breed from six breeding enterprises in the Novosibirsk Region have been studied using 11 microsatellite markers. No significant differences in genetic variability parameters were found between individual populations. Private alleles have been identified in five out of six populations. Five populations have shown inbreeding coefficient values (FIS) below zero, which indicates heterozygosity excess. The population distribution test, principal component analysis, FST and DEST values, cluster analysis, and phylogenetic analysis have revealed two populations genetically distinct from the others. Essentially, the genetic diversity parameters of the six studied Black Pied cattle populations from the Novosibirsk Region show no significant differences from other Russian populations of the breed. Excess heterozygosity is observed in most breeding enterprises, which is a sign of a low inbreeding rate. To maintain the genetic diversity of the Russian Black Pied cattle, we recommend focusing on the two populations with significant genetic distinctions from the others.

2022 ◽  
Vol 355 ◽  
pp. 02008
Yujun Chen ◽  
Wenqiang Yuan

In this paper a new search strategy for multi-objective optimization (MOO) with constraints is proposed based on a hybrid search mode (HSM). The search processes for feasible solutions and optimal solutions are executed in a mixed way for the existing methods. With regard to HSM, a hybrid search mode is proposed, which consists of two processes: Feasibility search mode (FSM) and optimal search mode (OSM). The executions of these two search modes are independent relatively and also adjusted according to the population distribution. In the early stage, FSM plays the leading role for exploring the feasible space since most of the individuals are infeasible. With the increase of the feasible individuals, OSM is the primary operation for the search of optimal individuals. The proposed method is simple to implement and need few extra parameter tuning. The handing method of constraints is tested on several multi-objective optimization problems with constraints. The remarkable results demonstrate its effectiveness and good performance.

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