ABSTRACT Background: Although post-traumatic stress disorder (PTSD) onset-persistence is thought to vary significantly by trauma type, most epidemiological surveys are incapable of assessing this because they evaluate lifetime PTSD only for traumas nominated by respondents as their ‘worst.’ Objective: To review research on associations of trauma type with PTSD in the WHO World Mental Health (WMH) surveys, a series of epidemiological surveys that obtained representative data on trauma-specific PTSD. Method: WMH Surveys in 24 countries (n = 68,894) assessed 29 lifetime traumas and evaluated PTSD twice for each respondent: once for the ‘worst’ lifetime trauma and separately for a randomly-selected trauma with weighting to adjust for individual differences in trauma exposures. PTSD onset-persistence was evaluated with the WHO Composite International Diagnostic Interview. Results: In total, 70.4% of respondents experienced lifetime traumas, with exposure averaging 3.2 traumas per capita. Substantial between-trauma differences were found in PTSD onset but less in persistence. Traumas involving interpersonal violence had highest risk. Burden of PTSD, determined by multiplying trauma prevalence by trauma-specific PTSD risk and persistence, was 77.7 person-years/100 respondents. The trauma types with highest proportions of this burden were rape (13.1%), other sexual assault (15.1%), being stalked (9.8%), and unexpected death of a loved one (11.6%). The first three of these four represent relatively uncommon traumas with high PTSD risk and the last a very common trauma with low PTSD risk. The broad category of intimate partner sexual violence accounted for nearly 42.7% of all person-years with PTSD. Prior trauma history predicted both future trauma exposure and future PTSD risk. Conclusions: Trauma exposure is common throughout the world, unequally distributed, and differential across trauma types with respect to PTSD risk. Although a substantial minority of PTSD cases remits within months after onset, mean symptom duration is considerably longer than previously recognized.
Pedro Menezes de Araujo, Isobel Claire Gormley, Thomas Brendan Murphy
Mortality data are relevant to demography, public health, and actuarial science. Whilst clustering is increasingly used to explore patterns in such data, no study has reviewed its application to country-level all-cause mortality. This review therefore summarises recent work and addresses key questions: why clustering is used, which mortality data are analysed, which methods are most common, and what main findings emerge. To address these questions, we examine studies applying clustering to country-level all-cause mortality, focusing on mortality indices, data sources, and methodological choices, and we replicate some approaches using Human Mortality Database (HMD) data. Our analysis reveals that clustering is mainly motivated by forecasting and by studying convergence and inequality. Most studies use HMD data from developed countries and rely on k-means, hierarchical, or functional clustering. Main findings include a persistent East-West European division across applications, with clustering generally improving forecast accuracy over single-country models. Overall, this review highlights the methodological range in the literature, summarises clustering results, and identifies gaps, such as the limited evaluation of clustering quality and the underuse of data from countries outside the high-income world.
Colorectal cancer (CRC) is a leading cause of death among digestive diseases and the second leading cause of cancer-related death in the United States (1). Despite the effectiveness and cost-effectiveness of screening (24), only 60% to 65% of the eligible population is current with screening (5), a rate that has fallen short of the goal of 80% by 2018 (2, 5, 6). This reflects concerns over the best test and strategy for screening. Colonoscopy is the most frequently used screening test in the United States (5), but several other countries use annual or biennial stool blood tests or a combination of stool testing and lower endoscopy (7, 8). Although studies have shown that guaiac-based fecal occult blood testing reduces CRC incidence and mortality (913), it has several shortcomings, including low single-application sensitivity for CRC, poor detection of advanced adenomas (those with a diameter 1 cm, villous histologic characteristics, or high-grade dysplasia), the need for dietary and medication restrictions, and the requirement for more than 1 specimen. Use of the fecal immunochemical test (FIT) for human globulin is more sensitive and specific than guaiac-based fecal occult blood testing for CRC and advanced adenomas and has higher rates of participation and acceptance (1416). However, studies evaluating FIT performance characteristics have shown inconsistent findings for CRC and advanced adenomas. A systematic review published in 2014 summarized performance characteristics for CRC (17) but not for advanced adenomas. The objectives of this systematic review and meta-analysis were to provide an updated summary of FIT performance for CRC, quantify FIT performance characteristics for advanced adenomas, and evaluate whether variation in reported performance characteristics among studies is a function of the threshold used to define a positive test result or the test brand. Methods Rather than developing and registering a new formal protocol, we used 2 prior systematic reviews as guides for our study methods (17, 18). We followed standard procedures for systematic reviews and reported results according to the PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) guidelines (19, 20). Data Sources and Searches We performed English-language searches of the Ovid MEDLINE, PubMed, Embase, and Cochrane databases from inception to 17 October 2018 to identify studies assessing performance of 1 or more FITs. Searches were done using various combinations of the following terms: feces, occult blood, colon cancer, cancer screening, early diagnosis, immunochemistry, and FIT (Appendix Table 1). We also reviewed reference lists of relevant systematic reviews and meta-analyses (17, 18) and of articles that met selection criteria. Appendix Table 1. Detailed Search Strategies Study Selection Two authors independently screened all titles and potentially relevant abstracts and then full texts of potentially eligible articles. Prospective or retrospective observational studies that were published in English; evaluated FIT sensitivity and specificity in asymptomatic, average-risk adults; and used colonoscopy as the reference standard were eligible for inclusion. Data only in abstract form or gray literature were not eligible. Data Extraction and Quality Assessment Two reviewers reviewed descriptive and quantitative data from each study. Data extraction was done primarily by 1 author (R.N.G.) and was independently validated by 2 others (T.F.I. or T.W.E.). For each study, we extracted data on sample size, mean age, brands of FIT used, thresholds for positivity (expressed as micrograms of hemoglobin per gram of feces), numbers of participants with CRC and advanced adenomas, and performance characteristics for both. Raw data on CRC and advanced adenomas were extracted when available. When only computed data were available, raw data were calculated based on identified proportions. For articles with missing data, the corresponding authors were contacted. When more than 1 FIT cutoff or threshold was used, performance characteristics for commonly used thresholds were extracted. Two authors (among T.F.I., R.N.G., and T.W.E.) independently assessed study characteristics and evaluated study quality by using the revised version of the QUADAS-2 (Quality Assessment of Diagnostic Accuracy Studies 2) tool (21). Discrepancies between reviewers for study quality assessment were resolved by discussion. The authors did not grade the quality of their own studies. Data Synthesis and Analysis Sensitivity and specificity at 1 or more thresholds were reported for each study. We combined studies and report results for CRC and advanced adenomas, with studies grouped by threshold (10 to 20 g/g). To assess statistical heterogeneity, we calculated the I 2 measure, which indicates the percentage of total variation across studies that is due to heterogeneity rather than chance (22). For all summary-level estimates, we used a bivariate generalized linear mixed model to simultaneously estimate pooled measures of sensitivity and specificity separately for CRC and advanced adenomas while accounting for the potential correlation between sensitivity and specificity. The bivariate approach provides unbiased estimates of sensitivity, specificity, and their correlation (23) and does not rely on an ad hoc continuity correction for zero marginal counts. Likelihood ratios were calculated using the bivariate estimates; positive likelihood ratios were calculated as sensitivity divided by (1 specificity), and negative likelihood ratios were calculated as (1 sensitivity) divided by specificity. Summary receiver-operating characteristic curves were obtained along with 95% confidence regions for the bivariate estimates of sensitivity and (1 specificity). We also combined studies by FIT brand and by threshold to enable indirect comparisons. Meta-DiSc software (Hospital Universitario Ramn y Cajal) (24) was used to calculate the I 2 measure. For all other summary estimates of performance characteristics, the glmer function (25) of the lme4 package (26) in R (R Foundation for Statistical Computing) (27) was used to estimate the bivariate generalized mixed models (details are provided in the Supplement). Supplement. Technical Appendix Role of the Funding Source The study was funded by the Department of Medicine and the Melvin and Bren Simon Cancer Center at the Indiana University School of Medicine and by the Regenstrief Institute. The funding sources had no role in the conception, design, or conduct of the study; analysis of the data; review of the manuscript; or the decision to submit it for publication. Results Our search strategy (Appendix Table 1) generated 4976 citations, among which 31 articles were included in the analysis (Figure 1; Appendix Table 2) (2858). Studies were published between 2001 and 2018. Funding sources were not reported for 10 studies and included federal government (n= 15), private or intramural (n= 4), and corporate (n= 2) sources for the other studies. The total number of participants was 120255, and sample sizes ranged from 284 to 21805. Mean age ranged from 48.2 to 64 years. All study populations comprised asymptomatic, mostly average-risk persons in the screening age range (generally 50 to 75 years) who enrolled in screening colonoscopy programs for cancer prevention. Persons with prior colorectal neoplasia, inflammatory bowel disease, high-risk family history, or colonoscopy in the previous 5 to 10 years were excluded, as were (post hoc) those with inadequate bowel preparation or incomplete colonoscopy. Figure 1. Evidence search and selection. FIT= fecal immunochemical test. Appendix Table 2. Characteristics of Included Studies Eighteen FITs were tested, with individual studies testing 1 to 6 FITs. OC-Sensor (Eiken Chemical) was tested in 14 (58%) studies (35, 3942, 4649, 51, 52, 54, 56, 57), including OC FIT-CHEK (Eiken Chemical) in 2 (48, 57) of those 14 studies, OC-Light (Eiken Chemical) in 5 studies (29, 36, 37, 43, 45), and OC-Hemodia (Eiken Chemical) and FOB Gold (Sentinel Diagnostics) in 3 studies each (28, 30, 32, 33, 55, 58). Many of the remaining FITs are or were available only in a single country or region. Thresholds for positivity ranged from 2 to 67 g/g, with 11 studies using a positivity threshold of less than 10 g/g, 17 using a threshold of 10 g/g, 9 using a threshold of 11 to 19 g/g, and 26 using a threshold of 20 g/g or greater. Performance characteristics of FITs for CRC and advanced adenomas based on each threshold tested for individual studies are shown in Appendix Table 2. All studies assessed the sensitivity and specificity of 1 or more FITs for advanced adenomas, which ranged in prevalence from 1.26% to 12.2%, and all but 3 studies (33, 39, 51) did so for CRC, which ranged in prevalence from 0.15% to 3.48%. We judged the quality of most studies as high (Appendix Figure 1). All were cross-sectional. Only 1 had a prospective casecontrol design (46); for this study, we used data only from the control group, which, as in the other studies, comprised persons having screening colonoscopy. A lack of detail in study methods for nearly half the studies precluded us from knowing whether a consecutive or random sample of persons participated. Despite this, we assessed most studies as having low to moderate risk of selection bias. For approximately 30% of the studies, it was unclear whether FIT results and colonoscopic findings were interpreted independently. In 25% of the studies, the interval between the FIT and colonoscopy was not specified. Appendix Figure 1. QUADAS-2 study quality stacked bar charts. Q = question; QUADAS-2 = Quality Assessment of Diagnostic Accuracy Studies 2. The studies tested 1 or more FITs; several used more than 1 threshold with the objective of determining the optimal one. The FIT was done before colonoscopy in all but 1 study (49), which provided no information. Although 5
Folke Brinkmann, A. Friedrichs, Georg M. N. Behrens
et al.
BACKGROUND Vulnerability to infectious diseases in refugees is dependent on country of origin, flight routes, and conditions. Information on specific medical needs of different groups of refugees is lacking. We assessed the prevalence of infectious diseases, immunity to vaccine-preventable diseases, and chronic medical conditions in children, adolescents, and adult refugees from Ukraine who arrived in Germany in 2022. METHODS Using different media, we recruited Ukrainian refugees at 13 sites between 9-12/2022. An antigen test for acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) infection, serologies for a range of vaccine-preventable diseases, as well as interferon gamma release assays (IGRAs) for tuberculosis (TB), and SARS-CoV-2 were performed. We assessed personal and family history of chronic medical conditions, infectious diseases, vaccination status, and conditions during migration. RESULTS Overall, 1793 refugees (1401 adults and 392 children/adolescents) were included. Most participants were females (n = 1307; 72·3%) and from Eastern or Southern Ukraine. TB IGRA was positive in 13% (n = 184) of the adults and in 2% (n = 7) of the children. Serology-based immunological response was insufficient in approximately 21% (360/1793) of the participants for measles, 32% (572/1793) for diphtheria, and 74% (1289/1793) for hepatitis B. CONCLUSIONS We show evidence of low serological response to vaccine-preventable infections and increased LTBI prevalence in Ukrainian refugees. These findings should be integrated into guidelines for screening and treatment of infectious diseases in migrants and refugees in Germany and Europe. Furthermore, low immunity for vaccine-preventable diseases in Ukrainians independent of their refugee status, calls for tailor-made communication efforts.
With a multicentric world forming and stratification of resource potential taking place, as well as with more small states in Europe and the world and emerging big multinationals here, small states receive more and more researchers’ attention: there appear papers analyzing activities of small states in Europe in the international arena in general and in international negotiations in particular. This article answers the following research question: What strategies and tactics allow small European states to strengthen their positions in negotiations (based on the case of the Benelux countries)? The strategies used by small countries in negotiations to compensate for limited resources is of scientific and practical interest as it can be applied by other states, namely Russia. Theoretically, the study is based on constructivist methodology as negotiation tactics effectively (re)formulate the issue, changing it through the use of a different context and/or lexical units, as well as on structural invariants of activity in negotiations. Discourse analysis and case study are used as research methods. The analysis identified the limitations that small European states, in particular the Benelux countries, face at each stage of international negotiations. The authors conclude that the types of behavior small European states demonstrate in international negotiations can be divided into those (1) aimed at increasing the “weight” of the state (e.g., interaction within international institutions, with NGOs and lobbies, organizing side events, etc.) and (2) focused on influencing the course of negotiations: tactics within the bargaining strategy (coalition-building, bargaining, etc.) and tactics based on persuasion ((re)framing, appealing to one’s own “example”, etc.). For small European countries, namely the Benelux countries, persuasion tactics are most typical, although other tactics are also used.
Political stability is crucial for the socioeconomic development of nations, particularly in geopolitically sensitive regions such as the Gulf Cooperation Council Countries, Saudi Arabia, UAE, Kuwait, Qatar, Oman, and Bahrain. This study focuses on predicting the political stability index for these six countries using machine learning techniques. The study uses data from the World Banks comprehensive dataset, comprising 266 indicators covering economic, political, social, and environmental factors. Employing the Edit Distance on Real Sequence method for feature selection and XGBoost for model training, the study forecasts political stability trends for the next five years. The model achieves high accuracy, with mean absolute percentage error values under 10, indicating reliable predictions. The forecasts suggest that Oman, the UAE, and Qatar will experience relatively stable political conditions, while Saudi Arabia and Bahrain may continue to face negative political stability indices. The findings underscore the significance of economic factors such as GDP and foreign investment, along with variables related to military expenditure and international tourism, as key predictors of political stability. These results provide valuable insights for policymakers, enabling proactive measures to enhance governance and mitigate potential risks.
Ignoring the differences between countries, human reproductive and dispersal behaviors can be described by some standardized models, so whether there is a universal law of population growth hidden in the abundant and unstructured data from various countries remains unclear. The age-specific population data constitute a three-dimensional tensor containing more comprehensive information. The existing literature often describes the characteristics of global or regional population evolution by subregion aggregation and statistical analysis, which makes it challenging to identify the underlying rules by ignoring national or structural details. Statistical physics can be used to summarize the macro characteristics and evolution laws of complex systems based on the attributes and motions of masses of individuals by decomposing high-dimensional tensors. Specifically, it can be used to assess the evolution of age structure in various countries over the past approximately 70 years, rather than simply focusing on the regions where aging has become apparent. It provides a universal scheme for the growing elderly and working age populations, indicating that the demographics on all continents are inevitably moving towards an aging population, including the current "young" continents of Africa, and Asia, South America with a recent "demographic dividend". It is a force derived from the "life cycle", and most countries have been unable to avoid this universal evolutionary path in the foreseeable future.
Introduction Tonsillitis is the third most frequently diagnosed infection in the pediatric age and is associated with significant morbidity and loss of school attendance. Throat swab cultures are useful for the confirmation of children with a clinically suspected tonsillitis. However, Somaliland is one of the underdeveloped countries with a low standard of sanitation and poor health seeking culture. Treatment of tonsillitis with antibiotics is irrational and not empirical. This study determined the bacterial throat swab culture positivity and antibiotic resistance profiles of the bacterial isolates among children 2–5 years of age with suspicion of tonsillitis at Hargeisa Group of Hospital, Somaliland. Materials and Methods A cross-sectional study was conducted from March to July 2020. A total of 374 children from 2 to 5 years of age suspicion of tonsillitis was included using a convenient sampling method. Throat swabs were collected, and bacterial isolation and identification were done using standard bacteriological procedures. Antimicrobial susceptibility testing was done using the disk diffusion method. Data on demographic variables and clinical profiles were collected using structured questionnaires. Logistic regression analysis was computed to identify factors associated with bacterial tonsillitis. Results Overall, 120 (32.1%) (95% CI 27.4–36.8%) of children were positive for bacterial throat cultures. Of these, 23 (19.2%) were mixed bacterial isolates. The most frequent bacterial isolates were beta-hemolytic streptococci 78 (55%), Staphylococcus aureus 42 (29%), and Streptococcus pneumoniae 10 (7%). Isolates revealed 83.3–100% rate of resistance to ampicillin. Beta-hemolytic streptococci isolates were 94.9% resistant to ampicillin. S. aureus was resistant to clarithromycin (38%) while S. pneumoniae isolates were 100% resistant to ampicillin. History of tonsillitis (AOR = 0.12; 95% CI = 0.06–0.21), difficulty in swallowing (AOR = 6.99; 95% CI = 3.56–13.73), and attending schools (AOR = 2.98; 95% CI = 1.64–5.42) were found to be associated with positive throat culture. Conclusions Resistance to ampicillin and MDR among beta-hemolytic streptococci and other isolates of throat colonizers in children with clinically suspected of bacterial tonsillitis are major concerns in Hargeisa, Somaliland. Therefore, treatments of cases are recommended to be guided by regular culture and antimicrobial susceptibility testing to prevent complications of tonsillitis and associated antibiotic resistance.
U. P. S. T. Force, Douglas K. Owens, Karina W. Davidson
et al.
Importance An abdominal aortic aneurysm (AAA) is typically defined as aortic enlargement with a diameter of 3.0 cm or larger. The prevalence of AAA has declined over the past 2 decades among screened men 65 years or older in various European countries. The current prevalence of AAA in the United States is unclear because of the low uptake of screening. Most AAAs are asymptomatic until they rupture. Although the risk for rupture varies greatly by aneurysm size, the associated risk for death with rupture is as high as 81%. Objective To update its 2014 recommendation, the USPSTF commissioned a review of the evidence on the effectiveness of 1-time and repeated screening for AAA, the associated harms of screening, and the benefits and harms of available treatments for small AAAs (3.0-5.4 cm in diameter) identified through screening. Population This recommendation applies to asymptomatic adults 50 years or older. However, the randomized trial evidence focuses almost entirely on men aged 65 to 75 years. Evidence Assessment Based on a review of the evidence, the USPSTF concludes with moderate certainty that screening for AAA in men aged 65 to 75 years who have ever smoked is of moderate net benefit. The USPSTF concludes with moderate certainty that screening for AAA in men aged 65 to 75 years who have never smoked is of small net benefit. The USPSTF concludes that the evidence is insufficient to determine the net benefit of screening for AAA in women aged 65 to 75 years who have ever smoked or have a family history of AAA. The USPSTF concludes with moderate certainty that the harms of screening for AAA in women aged 65 to 75 years who have never smoked and have no family history of AAA outweigh the benefits. Recommendations The USPSTF recommends 1-time screening for AAA with ultrasonography in men aged 65 to 75 years who have ever smoked. (B recommendation) The USPSTF recommends that clinicians selectively offer screening for AAA with ultrasonography in men aged 65 to 75 years who have never smoked rather than routinely screening all men in this group. (C recommendation) The USPSTF recommends against routine screening for AAA with ultrasonography in women who have never smoked and have no family history of AAA. (D recommendation) The USPSTF concludes that the current evidence is insufficient to assess the balance of benefits and harms of screening for AAA with ultrasonography in women aged 65 to 75 years who have ever smoked or have a family history of AAA. (I statement).
Jean Marie Tshimula, D'Jeff K. Nkashama, Kalonji Kalala
et al.
Electronic Health Record (EHR) has become an essential tool in the healthcare ecosystem, providing authorized clinicians with patients' health-related information for better treatment. While most developed countries are taking advantage of EHRs to improve their healthcare system, it remains challenging in developing countries to support clinical decision-making and public health using a computerized patient healthcare information system. This paper proposes a novel EHR architecture suitable for developing countries--an architecture that fosters inclusion and provides solutions tailored to all social classes and socioeconomic statuses. Our architecture foresees an internet-free (offline) solution to allow medical transactions between healthcare organizations, and the storage of EHRs in geographically underserved and rural areas. Moreover, we discuss how artificial intelligence can leverage anonymous health-related information to enable better public health policy and surveillance.
Nathan Kammoun, Lakmal Meegahapola, Daniel Gatica-Perez
Understanding the social context of eating is crucial for promoting healthy eating behaviors. Multimodal smartphone sensor data could provide valuable insights into eating behavior, particularly in mobile food diaries and mobile health apps. However, research on the social context of eating with smartphone sensor data is limited, despite extensive studies in nutrition and behavioral science. Moreover, the impact of country differences on the social context of eating, as measured by multimodal phone sensor data and self-reports, remains under-explored. To address this research gap, our study focuses on a dataset of approximately 24K self-reports on eating events provided by 678 college students in eight countries to investigate the country diversity that emerges from smartphone sensors during eating events for different social contexts (alone or with others). Our analysis revealed that while some smartphone usage features during eating events were similar across countries, others exhibited unique trends in each country. We further studied how user and country-specific factors impact social context inference by developing machine learning models with population-level (non-personalized) and hybrid (partially personalized) experimental setups. We showed that models based on the hybrid approach achieve AUC scores up to 0.75 with XGBoost models. These findings emphasize the importance of considering country differences in building and deploying machine learning models to minimize biases and improve generalization across different populations.
(1) Background: Adolescents-and-young-adults (AYA) are prone to anxiety. This study assessed AYA’s level of anxiety during the COVID-19 pandemic; and determined if anxiety levels were associated with country-income and region, socio-demographic profile and medical history of individuals. (2) Methods: A survey collected data from participants in 25 countries. Dependent-variables included general-anxiety level, and independent-variables included medical problems, COVID-19 infection, age, sex, education, and country-income-level and region. A multilevel-multinomial-logistic regression analysis was conducted to determine the association between dependent, and independent-variables. (3) Results: Of the 6989 respondents, 2964 (42.4%) had normal-anxiety, and 2621 (37.5%), 900 (12.9%) and 504 (7.2%) had mild, moderate and severe-anxiety, respectively. Participants from the African region (AFR) had lower odds of mild, moderate and severe than normal-anxiety compared to those from the Eastern-Mediterranean-region (EMR). Also, participants from lower-middle-income-countries (LMICs) had higher odds of mild and moderate than normal-anxiety compared to those from low-income-countries (LICs). Females, older-adolescents, with medical-problems, suspected-but-not-tested-for-COVID-19, and those with friends/family-infected with COVID-19 had significantly greater odds of different anxiety-levels. (4) Conclusions: One-in-five AYA had moderate to severe-anxiety during the COVID-19-pandemic. There were differences in anxiety-levels among AYAs by region and income-level, emphasizing the need for targeted public health interventions based on nationally-identified priorities.
Many industrialized nations have followed the lead of the United States (US) in reducing workers’ wages and cutting government safety nets, while giving their populaces the false impression that non-governmental organizations can meet the food and basic survival needs of their low-income residents. The history of the last 50 years and the global COVID-19 pandemic demonstrate why that is a mistake, leading to vastly increased household food insecurity, poverty, and hunger. This paper takes a close look at US data to help to better understand the significant impact US federal government policy measures had on limiting hunger throughout the pandemic and how we can learn from these outcomes to finally end hunger in America and other developed nations. The top three policy prescriptions vital in ending household food insecurity in the US and industrialized countries are as follows: (1) to create jobs; raise wages; make high quality healthcare and prescription medicine free; and ensure that high quality childcare, education, transportation, and broad-band access are affordable to all; (2) to enact a comprehensive “Assets Empowerment Agenda” to help low-income people move from owing to owning in order to develop middle-class wealth; and (3) when the above two steps are inadequate, ensure a robust government safety net for struggling residents that provides cash, food, and housing assistance.
We study low-energy scattering of spin-1/2 baryons from the perspective of quantum information science, focusing on the correlation between entanglement minimization and the appearance of accidental symmetries. The baryon transforms as an octet under the SU(3) flavor symmetry and its interactions below the pion threshold are described by contact operators in an effective field theory (EFT) of QCD. Despite there being 64 channels in the 2-to-2 scattering, only six independent operators in the EFT are predicted by SU(3). We show that successive entanglement minimization in SU(3)-symmetric channels are correlated with increasingly large emergent symmetries in the EFT. In particular, we identify scattering channels whose entanglement suppression are indicative of emergent SU(6), SO(8), SU(8), and SU(16) symmetries. We also observe the appearance of non-relativistic conformal invariance in channels with unnaturally large scattering lengths. Improved precision from lattice simulations could help determine the degree of entanglement suppression, and consequently the amount of accidental symmetry, in low-energy QCD.
Quantum dynamics can be simulated on a quantum computer by exponentiating elementary terms from the Hamiltonian in a sequential manner. However, such an implementation of Trotter steps has gate complexity depending on the total Hamiltonian term number, comparing unfavorably to algorithms using more advanced techniques. We develop methods to perform faster Trotter steps with complexity sublinear in the number of terms. We achieve this for a class of Hamiltonians whose interaction strength decays with distance according to power law. Our methods include one based on a recursive block encoding and one based on an average-cost simulation, overcoming the normalization-factor barrier of these advanced quantum simulation techniques. We also realize faster Trotter steps when certain blocks of Hamiltonian coefficients have low rank. Combining with a tighter error analysis, we show that it suffices to use $\left(η^{1/3}n^{1/3}+\frac{n^{2/3}}{η^{2/3}}\right)n^{1+o(1)}$ gates to simulate uniform electron gas with $n$ spin orbitals and $η$ electrons in second quantization in real space, asymptotically improving over the best previous work. We obtain an analogous result when the external potential of nuclei is introduced under the Born-Oppenheimer approximation. We prove a circuit lower bound when the Hamiltonian coefficients take a continuum range of values, showing that generic $n$-qubit $2$-local Hamiltonians with commuting terms require at least $Ω(n^2)$ gates to evolve with accuracy $ε=Ω(1/poly(n))$ for time $t=Ω(ε)$. Our proof is based on a gate-efficient reduction from the approximate synthesis of diagonal unitaries within the Hamming weight-$2$ subspace, which may be of independent interest. Our result thus suggests the use of Hamiltonian structural properties as both necessary and sufficient to implement Trotter steps with lower gate complexity.
Dephney Mathebula, Abigail Amankwah, Kossi Amouzouvi
et al.
The rapid development of vaccines to combat the spread of COVID-19 disease caused by the SARS-CoV-2 virus is a great scientific achievement. Before the development of the COVID-19 vaccines, most studies capitalized on the available data that did not include pharmaceutical measures. Such studies focused on the impact of non-pharmaceutical measures (e.g social distancing, sanitation, wearing of face masks, and lockdown) to study the spread of COVID-19. In this study, we used the SIDARTHE-V model which is an extension of the SIDARTHE model wherein we include vaccination roll outs. We studied the impact of vaccination on the severity (deadly nature) of the virus in African countries. Model parameters were extracted by fitting simultaneously the COVID-19 cumulative data of deaths, recoveries, active cases, and full vaccinations reported by the governments of Ghana, Kenya, Mozambique, Nigeria, South Africa, Togo, and Zambia. With countries having some degree of variation in their vaccination programs, we considered the impact of vaccination campaigns on the death rates in these countries. The study showed that the cumulative death rates declined drastically with the increased extent of vaccination in each country; while infection rates were sometimes increasing with the arrival of new waves, the death rates did not increase as we saw before vaccination.
Birth cohorts are those among observational studies that provide understanding of the natural history and causality of diseases since early in life. Discussions during an International Association for Dental Research symposium in London, United Kingdom, in 2018, followed by a workshop in Bangkok, Thailand, in 2019, concluded that there are few birth cohort studies that consider oral health and that a broader discussion on similarities and differences among those studies would be valuable. This article aims to 1) bring together available long-term data of oral health birth cohort studies from the low, middle, and high-income countries worldwide and 2) describe similarities and differences among these studies. This work comprises 15 studies from all 5 continents. The most studied dental conditions and exposures are identified; findings are summarized; and methodological differences and similarities among studies are presented. Methodological strengths and weaknesses are also highlighted. Findings are summarized in 1) the negative impact of detrimental socioeconomic status on oral health changes over time, 2) the role of unfavorable patterns of dental visiting on oral health, 3) associations between general and oral health, 4) nutritional and dietary effects on oral health, and 5) intergenerational influences on oral health. Dental caries and dental visiting patterns have been recorded in all studies. Sources of fluoride exposure have been documented in most of the more recent studies. Despite some methodological differences in the way that the exposures and outcomes were measured, some findings are consistent. Predictive models have been used with caries risk tools, periodontitis occurrence, and permanent dentition orthodontic treatment need. The next steps of the group’s work are as follows: 1) establishing a consortium of oral health birth cohort studies, 2) conducting a scoping review, 3) exploring opportunities for pooled data analyses to answer pressing research questions, and 4) promoting and enabling the development of the next generation of oral health researchers.
Anticipating the quantity of new associated or affirmed cases with novel coronavirus ailment 2019 (COVID-19) is critical in the counteraction and control of the COVID-19 flare-up. The new associated cases with COVID-19 information were gathered from 20 January 2020 to 21 July 2020. We filtered out the countries which are converging and used those for training the network. We utilized the SARIMAX, Linear regression model to anticipate new suspected COVID-19 cases for the countries which did not converge yet. We predict the curve of non-converged countries with the help of proposed Statistical SARIMAX model (SSM). We present new information investigation-based forecast results that can assist governments with planning their future activities and help clinical administrations to be more ready for what's to come. Our framework can foresee peak corona cases with an R-Squared value of 0.986 utilizing linear regression and fall of this pandemic at various levels for countries like India, US, and Brazil. We found that considering more countries for training degrades the prediction process as constraints vary from nation to nation. Thus, we expect that the outcomes referenced in this work will help individuals to better understand the possibilities of this pandemic.