Calculating effective gun policies

Following recent shootings in the USA, a debate has erupted, one side favoring stricter gun control, the other promoting protection through more weapons. We provide a scientific foundation to inform this debate, based on mathematical, epidemiological models that quantify the dependence of firearm-related death rates of people on gun policies. We assume a shooter attacking a single individual or a crowd. Two strategies can minimize deaths in the model, depending on parameters: either a ban of private firearms possession, or a policy allowing the general population to carry guns. In particular, the outcome depends on the fraction of offenders that illegally possess a gun, on the degree of protection provided by gun ownership, and on the fraction of the population who take up their right to own a gun and carry it with them when attacked, parameters that can be estimated from statistical data. With the measured parameters, the model suggests that if the gun law is enforced at a level similar to that in the United Kingdom, gun-related deaths are minimized if private possession of firearms is banned. If such a policy is not practical or possible due to constitutional or cultural constraints, the model and parameter estimation indicate that a partial reduction in firearm availability can lead to a reduction in gun-induced death rates, even if they are not minimized. Most importantly, our analysis identifies the crucial parameters that determine which policy reduces the death rates, providing guidance for future statistical studies that will be necessary for more refined quantitative predictions

Genetic data of museum specimens allow for inferring evolutionary history of the cosmopolitan genus Sirthenea (Heteroptera: Reduviidae)

Among the 30 known genera within subfamily Peiratinae, only the genus Sirthenea has a cosmopolitan distribution. The results of our studies are the first comprehensive analysis concerning one of the representatives of mentioned subfamily based on joint phylogenetic analyses ofmolecular andmorphological data as well asmolecular dating. A total of 32 species were included into the dataset with all known species of the genus Sirthenea. Material of over 400 dry specimens was examined for the morphological part of this study. The cosmopolitan distribution of Sirthenea and the inaccessibility of specimens preserved in alcohol required the extraction of DNA from the dried skeletal muscles of specimens deposited in 24 entomological collections. The oldest specimens used for the successful extraction and sequencing were collected more than 120 years ago in India. We performed Bayesian Inference analyses of molecular and morphological data separately, as well as combined analysis. The molecular and morphological data obtained during our research verify the correlation of the divergence dates of all known Sirthenea species. Results of the relaxed molecular clock analysis of the molecular data show that, the genus Sirthenea started diverging in the Late Cretaceous into two clades, which subsequently began to branch off in the Paleocene. Our results of phylogenetic analyses suggest that the fossula spongiosa and its development could be one of the most important morphological characters in the evolution of the genus, most likely associated with the ecological niche inhabited by Sirthenea representatives. Confirmation of the results obtained in our studies is the reconciliation of the evolutionary history of Sirthenea with the biogeographical processes that have shaped current global distribution of the genus

Analysis of the needs and possibilities of using psychological help among the society

Introduction Young people find themselves in stressful situations more and more frequently. Mental health and access to professional psychical help is necessary. Unfortunately, the availability of the psychologist's offices, as well as knowledge about mental health, is very limited. Aim of the study We aimed to check factors that cause stress and the access to psychological help in Poland. Material and method In order to analyze the issue, an Internet survey was prepared and disseminated in  February and March 2022. Results Over 80% of respondents claimed that sometime in their life they needed psychological help, although the majority of them did not seek professional help. 41,1% of people who took part in the survey could get help from psychologists in their place of work or study, but over 83% of them did not seek help there. Everyday problems and situations in work, school or university were mentioned as the most stressful situations (63,7%). According to the respondents' opinion, problems with concentration and nervousness (80,6% and 76,6% respectively) due to stress have a negative influence on their health. 74,2% of young people consider themselves as not stress-resistant. The best option to deal with stress is to listen to music or to converse with their closest ones. Conclusion Everyone should have ensured good access to psychological help. There is a great demand for it, regardless of gender or age. Despite the need to see an expert, the majority of people do not ask for help

Crystal structures of cristobalite-type and coesite-type PON redetermined on the basis of single-crystal X-ray diffraction data

Hitherto, phosphorus oxonitride (PON) could not be obtained in the form of single crystals and only powder diffraction experiments were feasible for structure studies. In the present work we have synthesized two polymorphs of phosphorus oxonitride, cristobalite-type (cri-PON) and coesite-type (coe-PON), in the form of single crystals and reinvestigated their crystal structures by means of in house and synchrotron single-crystal X-ray diffraction. The crystal structures of cri-PON and coe-PON are built from PO2N2 tetrahedral units, each with a statistical distribution of oxygen and nitrogen atoms. The crystal structure of the coe-PON phase has the space group C2/c with seven atomic sites in the asymmetric unit [two P and three (N,O) sites on general positions, one (N,O) site on an inversion centre and one (N,O) site on a twofold rotation axis], while the cri-PON phase possesses tetragonal I-42d symmetry with two independent atoms in the asymmetric unit [the P atom on a fourfold inversion axis and the (N,O) site on a twofold rotation axis]. In comparison with previous structure determinations from powder data, all atoms were refined with anisotropic displacement parameters, leading to higher precision in terms of bond lengths and angles

Uncertainty in historical land-use reconstructions with topographic maps

The paper presents the outcomes of the uncertainty investigation of a long-term forest cover change analysis in the Polish Carpathians (nearly 20,000 km2) and Swiss Alps (nearly 10,000 km2) based on topographic maps. Following Leyk et al. (2005) all possible uncertainties are grouped into three domains - production-oriented, transformation- oriented and application-oriented. We show typical examples for each uncertainty domain, encountered during the forest cover change analysis and discuss consequences for change detection. Finally, a proposal for reliability assessment is presented

The level of physical activity in the lifestyle of physical education students

Subject: The level of physical activity in the lifestyle of physical education students Introduction: Physical activity is defined as voluntary and spontaneous physical activity practiced during leisure time. Thanks to it, the body can function properly and develop on many levels. It plays an important role in social and physical development, as well as intellectual and emotional development. It finds its place in the fight against civilization diseases, it is also beneficial in resisting many other diseases.    Aim: The aim of the article is to assess the level of physical activity of physical education students of various specializations.   Material and methods: The research was conducted among students of physical education at the University of Rzeszów. 60 people took part in them - 38 women and 22 men aged 19-30. The respondents answered anonymously to 18 closed, single-choice questions.   Results: The majority of students are engaged in physical activity outside a college, and 65% of it is at amateur level activity. The most common reason why respondents take up physical activity is to improve the functional fitness of the body. 58% of the respondents undertook physical activity more than 3 times a week.   Conclusions: Most of the respondents do physical activity outside of their studies. The most common reason for taking up physical activity among the respondents was the improvement of the functional fitness of the body, and the factors influencing the fact that students are physically active were to the greatest extent sports activitiesSubject: The level of physical activity in the lifestyle of physical education students Introduction: Physical activity is defined as voluntary and spontaneous physical activity practiced during leisure time. Thanks to it, the body can function properly and develop on many levels. It plays an important role in social and physical development, as well as intellectual and emotional development. It finds its place in the fight against civilization diseases, it is also beneficial in resisting many other diseases.   Aim: The aim of the article is to assess the level of physical activity of physical education students of various specializations.   Material and methods: The research was conducted among students of physical education at the University of Rzeszów. 60 people took part in them - 38 women and 22 men aged 19-30. The respondents answered anonymously to 18 closed, single-choice questions.   Results: The majority of students are engaged in physical activity outside a college, and 65% of it is at amateur level activity. The most common reason why respondents take up physical activity is to improve the functional fitness of the body. 58% of the respondents undertook physical activity more than 3 times a week.   Conclusions: Most of the respondents do physical activity outside of their studies. The most common reason for taking up physical activity among the respondents was the improvement of the functional fitness of the body, and the factors influencing the fact that students are physically active were to the greatest extent sports activities   Key words: physical activity; lifestyle; physical education; student

Selected school solutions in the field of a healthy lifestyle among children and adolescents

Introduction and aim: Lifestyle is the daily behaviors, habits and activities adopted by people. It is one of the factors that largely determines the state of human health. It is important to pay attention to what habits and activities we implement in our lives. The source of behaviors are usually attitudes and values acquired in the family and the nearest social environment. The basic categories of pro-health behaviours are related to physical health, psychosocial health, health prevention and avoiding harmful behaviours, preventing an illness and supporting recovery. Anti-health behaviors contribute to health disorders, negative impacts in emotional, physical and psychosocial sphere. The aim of the study was to present selected school solutions in the field of pro-healthy lifestyle among children and adolescents, the influence of pro-healthy lifestyle and assessment of the implementation of health education at schools. Material and method: 85 children and adolescents in the age range of 10-19+ years participated in the study. Twenty-three students in the age range of 10-12 years, 27 students in the age range of 13-16 years and 35 students in the age range of 17-19+ years were surveyed. Twenty-eight males and 57 females took the survey. Results: Respondents most often engage in physical activity 2-3 times per week. The vast majority of respondents actively participate in physical education classes at school as well as undertake extracurricular physical activity. The most popular activities are cycling and team games. The main source of knowledge about pro-healthy lifestyle among children and adolescents is the Internet and the least popular is the press. Conclusions: The majority of students know what a pro-healthy lifestyle is, while less than half of the respondents have no such knowledge. The researched gain knowledge about the way of promoting pro-healthy lifestyle by school, most often through the organization of "Health Day". The majority of children and adolescents participate in extracurricular physical activity, while the rest of the respondents do not undertake such activity