Semi-stochastic full configuration interaction quantum Monte Carlo: Developments and application.

We expand upon the recent semi-stochastic adaptation to full configuration interaction quantum Monte Carlo (FCIQMC). We present an alternate method for generating the deterministic space without a priori knowledge of the wave function and present stochastic efficiencies for a variety of both molecular and lattice systems. The algorithmic details of an efficient semi-stochastic implementation are presented, with particular consideration given to the effect that the adaptation has on parallel performance in FCIQMC. We further demonstrate the benefit for calculation of reduced density matrices in FCIQMC through replica sampling, where the semi-stochastic adaptation seems to have even larger efficiency gains. We then combine these ideas to produce explicitly correlated corrected FCIQMC energies for the beryllium dimer, for which stochastic errors on the order of wavenumber accuracy are achievable.N.S.B. gratefully acknowledges Trinity College, Cambridge for funding. J.S.S. acknowledges the research environment provided by the Thomas Young Centre under Grant No. TYC-101. G.H.B. gratefully acknowledges the Royal Society for a university research fellowship. This work has been supported by the EPSRC under grant no. EP/J003867/1.This is the author accepted manuscript. The final version is available from AIP at http://scitation.aip.org/content/aip/journal/jcp/142/18/10.1063/1.4920975

Performance Evaluation Of The New Natural And Environmentally Friendly Material For Lost Circulation Control At High Pressure And Hight Temperature

Lost circulation refers to the loss of a part or whole drilling fluid into the formation and is considered as one of the most challenges in drilling operations. It could be occurred either naturally in highly fractured formations or induced by excessive overbalance pressure which leads to crack and rupture the formations being drilling and thereby inducing the loss of the mud into them. There are a number of treatments for lost circulation and perhaps the using of lost circulation materials (LCMs) is one of the common treatments. LCM is any material that used as an additive in the drilling fluid to seal and plug the openings in the formations. LCM manufacturers are continually introducing hundreds of materials every year. Recently, many research and studies had been done and continue for developing and investigating natural LCMs as alternatives for the conventional LCMs. In this study, a pomegranate peel (PP) has been developed and evaluated to be used as a natural LCM. The main two advantages of the PP LCM over the conventional LCM are its cost and naturally friendly properties. A series of filtration tests has been conducted on various sizes and concentrations of PP in order to investigate the effects of the size and percent of the additive on lost control characteristics. Moreover, for the purpose of comparison, a number of filtration tests has been conducted for similar sizes and precents of one of the most used LCM, carbonate calcium. It has been observed that the filtrate rate for the reference mud was 32 ml/30 min. While, the optimum reduction of 81% of the filtrate has been gained by addition of 15 ppb of the fine sized (less than 75 microns) PP. Meanwhile, only 47% of the lost being control through the addition of 20 ppb of the fine sized carbonate calcium

Drilling Pipe Corrosion Reduction Using Natural, Biodegradable, and Environmentally Friendly Additive to the Drilling Fluid

Corrosion is one of the disasters attacking the drilling tools, particularly the drill pipes. Drilling fluid is the corrosive that increase the rate of corrosion in the pipes. In this study, it is intended to reduce the corrosivity of drilling fluid using a Prosopis farcta powder material. A natural, biodegradable, and environmentally friendly additive is added to the fluid in different particle sizes and amounts to obtain the lowest corrosion rate. Experiments are conducted in a well-like environment (high pressure high temperature filter press) over a wide range of parameters including pressure, temperature, and properties of the drilling fluid under dynamic conditions. The aim is to eliminate or reduce the corrosivity of the mud as well as to control the losses. The results showed a lower corrosion rate, 0.0029 mm/year, using P. farcta material in comparison with those obtained by researchers in the previous studies

Comparing effects of beetroot juice and Mediterranean diet on liver enzymes and sonographic appearance in patients with non-alcoholic fatty liver disease: a randomized control trials

BackgroundIn both developed and developing countries, non-alcoholic fatty liver disease (NAFLD) has lately risen to the top of the list of chronic liver illnesses. Although there is no permanent cure, early management, diagnosis, and treatment might lessen its effects. The purpose of conducting the current study is to compare the effects of beetroot juice and the Mediterranean diet on the lipid profile, level of liver enzymes, and liver sonography in patients with NAFLD.MethodsIn this randomized controlled trial, 180 people with a mean age of (45.19 ± 14.94) years participated. Participants ranged in age from 19 to 73. The mean weight before intervention was (82.46 ± 5.97) kg, while the mean weight after intervention was roughly (77.88 ± 6.26) kg. The trial lasted for 12 weeks. The participants were split into four groups: control, a Mediterranean diet with beet juice (BJ + MeD), Mediterranean diet alone (MeD), and beetroot juice (BJ). The Mediterranean diet included fruits, vegetables, fish, poultry, and other lean meats (without skin), sources of omega-3 fatty acids, nuts, and legumes. Beetroot juice had 250 mg of beetroot. Data analysis was done using SPSS software (version 26.0). p < 0.05 is the statistical significance level.ResultsFollowing the intervention, Serum Bilirubin, alkaline phosphatase (ALP), alanine transaminase (ALT), serum cholesterol (CHOL), triglyceride (TG), and low-density lipoprotein (LDL) levels were significantly decreased in the BJ + MeD, BJ, and MeD groups (p = 0.001). Also, high-density lipoprotein (HDL) significantly increased in the BJ + MeD, BJ, and MeD groups (p = 0.001), while decreasing in the Control group (p = 0.001).ConclusionThe research findings indicate a significant reduction in hepatic steatosis among the groups receiving beetroot juice (BJ) and beetroot juice combined with the Mediterranean diet (BJ + MeD). This suggests that beetroot juice holds potential as an effective treatment for non-alcoholic fatty liver disease (NAFLD) in adults. Furthermore, the combination of beetroot juice with the Mediterranean diet showed enhanced efficacy in addressing NAFLD.Clinical trial registration:ClinicalTrials.gov, identifier NCT05909631

COVID-19 Vaccination Among Diverse Population Groups in the Northern Governorates of Iraq

Objectives: The present study was carried out to investigate COVID-19 vaccination coverage among populations of internally displaced persons (IDPs), refugees, and host communities in northern Iraq and the related underlying factors.Methods: Through a cross-sectional study conducted in five governorates in April–May 2022, 4,564 individuals were surveyed. Data were collected through an adapted questionnaire designed to gather data on participants.Results: 4,564 subjects were included (59.55% were 19–45 years old; 54.51% male). 50.48% of the participants (51.49% of host communities, 48.83% of IDPs, and 45.87% of refugees) had been vaccinated with at least one dose of COVID-19 vaccine. 40.84% of participants (42.28% of host communities, 35.75% of IDPs, and 36.14% of refugees) had been vaccinated by two doses, and 1.56% (1.65% of host communities, 0.93% of IDPs, and 1.46% of refugees) were vaccinated with three doses.Conclusion: Sociodemographic factors including age, gender, education, occupation, and nationality could affect vaccination coverage. Moreover, higher acceptance rate of vaccination is associated with belief in vaccine safety and effectiveness and trust in the ability of the vaccine to prevent complications

The roles of vicariance and isolation by distance in shaping biotic diversification across an ancient archipelago: evidence from a Seychelles caecilian amphibian

© 2020 The Authors. Published by BMC. This is an open access article available under a Creative Commons licence. The published version can be accessed at the following link on the publisher’s website: https://doi.org/10.1186/s12862-020-01673-wBackground Island systems offer excellent opportunities for studying the evolutionary histories of species by virtue of their restricted size and easily identifiable barriers to gene flow. However, most studies investigating evolutionary patterns and processes shaping biotic diversification have focused on more recent (emergent) rather than ancient oceanic archipelagos. Here, we focus on the granitic islands of the Seychelles, which are unusual among island systems because they have been isolated for a long time and are home to a monophyletic radiation of caecilian amphibians that has been separated from its extant sister lineage for ca. 65–62 Ma. We selected the most widespread Seychelles caecilian species, Hypogeophis rostratus, to investigate intraspecific morphological and genetic (mitochondrial and nuclear) variation across the archipelago (782 samples from nine islands) to identify patterns and test processes that shaped their evolutionary history within the Seychelles. Results Overall a signal of strong geographic structuring with distinct northern- and southern-island clusters were identified across all datasets. We suggest that these distinct groups have been isolated for ca. 1.26 Ma years without subsequent migration between them. Populations from the somewhat geographically isolated island of Frégate showed contrasting relationships to other islands based on genetic and morphological data, clustering alternatively with northern-island (genetic) and southern-island (morphological) populations. Conclusions Although variation in H. rostratus across the Seychelles is explained more by isolation-by-distance than by adaptation, the genetic-morphological incongruence for affinities of Frégate H. rostratus might be caused by local adaptation over-riding the signal from their vicariant history. Our findings highlight the need of integrative approaches to investigate fine-scale geographic structuring to uncover underlying diversity and to better understand evolutionary processes on ancient, continental islands.Funding for this research was provided by two grants from the National Science Foundation (BSR 88–17453, BSR 90–24505) [funding for fieldwork and lab work], two grants from the National Geographic Society (Grants 1977: 1633, 1743) [funding for fieldwork], three grants from the University of Michigan Office of the Vice President for Research, and a Research Partnership Award from the University of Michigan to RAN [morphology work]; a joint NHM-UCL IMPACT studentship [to fund STM’s PhD, lab work and fieldwork], Mohamed Bin Zayed Species Conservation Fund [funding for fieldwork] and Systematics Research Fund [funding for fieldwork] to STM; an Institutional Development Award (IDeA) from the National Institute of General Medical Sciences of the National Institutes of Health under Grant #P20GM103408 to LL [funding for lab work]; a NERC/BBSRC SynTax grant [funding for fieldwork and collaboration], and Darwin Initiative (grant 19–002) [funding for fieldwork, lab work and capacity building] with partners Bristol University, Islands Conservation Society, Seychelles Islands Foundation, Seychelles Ministry of Environment, Seychelles National Parks Authority, Seychelles Natural History Museum, University of Kent, Zoological Society of London to MW, DJG, JJD. The funding bodies played no role in the design of the study and collection, analysis, and interpretation of data and in writing the manuscript.Published onlin

Measurements of differential cross-sections in top-quark pair events with a high transverse momentum top quark and limits on beyond the Standard Model contributions to top-quark pair production with the ATLAS detector at √s = 13 TeV

Cross-section measurements of top-quark pair production where the hadronically decaying top quark has transverse momentum greater than 355 GeV and the other top quark decays into ℓνb are presented using 139 fb−1 of data collected by the ATLAS experiment during proton-proton collisions at the LHC. The fiducial cross-section at s = 13 TeV is measured to be σ = 1.267 ± 0.005 ± 0.053 pb, where the uncertainties reflect the limited number of data events and the systematic uncertainties, giving a total uncertainty of 4.2%. The cross-section is measured differentially as a function of variables characterising the tt¯ system and additional radiation in the events. The results are compared with various Monte Carlo generators, including comparisons where the generators are reweighted to match a parton-level calculation at next-to-next-to-leading order. The reweighting improves the agreement between data and theory. The measured distribution of the top-quark transverse momentum is used to search for new physics in the context of the effective field theory framework. No significant deviation from the Standard Model is observed and limits are set on the Wilson coefficients of the dimension-six operators OtG and Otq(8), where the limits on the latter are the most stringent to date. [Figure not available: see fulltext.]

Direct constraint on the Higgs–charm coupling from a search for Higgs boson decays into charm quarks with the ATLAS detector

A search for the Higgs boson decaying into a pair of charm quarks is presented. The analysis uses proton–proton collisions to target the production of a Higgs boson in association with a leptonically decaying W or Z boson. The dataset delivered by the LHC at a centre-of-mass energy of and recorded by the ATLAS detector corresponds to an integrated luminosity of 139 fb−1. Flavour-tagging algorithms are used to identify jets originating from the hadronisation of charm quarks. The analysis method is validated with the simultaneous measurement of WW, WZ and ZZ production, with observed (expected) significances of 2.6 (2.2) standard deviations above the background-only prediction for the (W/Z)Z(→cc¯) process and 3.8 (4.6) standard deviations for the (W/Z)W(→cq) process. The (W/Z)H(→cc¯) search yields an observed (expected) upper limit of 26 (31) times the predicted Standard Model cross-section times branching fraction for a Higgs boson with a mass of , corresponding to an observed (expected) constraint on the charm Yukawa coupling modifier |κc|<8.5 (12.4), at the 95% confidence level. A combination with the ATLAS (W/Z)H,H→bb¯ analysis is performed, allowing the ratio κc/κb to be constrained to less than 4.5 at the 95% confidence level, smaller than the ratio of the b- and c-quark masses, and therefore determines the Higgs-charm coupling to be weaker than the Higgs-bottom coupling at the 95% confidence level