Category: Nevin Manimala

J Synchrotron Radiat. 2023 Jan 1;30(Pt 1):217-226. doi: 10.1107/S1600577522010748. Epub 2023 Jan 1.

ABSTRACT

FOCUS (Fast Monte CarlO approach to Coherence of Undulator Sources) is a new GPU-based simulation code to compute the transverse coherence of undulator radiation from ultra-relativistic electrons. The core structure of the code, which is written in the language C++ accelerated with CUDA, combines an analytical description of the emitted electric fields and massively parallel computations on GPUs. The combination is rigorously justified by a statistical description of synchrotron radiation based on a Fourier optics approach. FOCUS is validated by direct comparison with multi-electron Synchrotron Radiation Workshop (SRW) simulations, evidencing a reduction in computation times by up to five orders of magnitude on a consumer laptop. FOCUS is then applied to systematically study the transverse coherence in typical third- and fourth-generation facilities, highlighting peculiar features of undulator sources close to the diffraction limit. FOCUS is aimed at fast evaluation of the transverse coherence of undulator radiation as a function of the electron beam parameters, to support and help prepare more advanced and detailed numerical simulations with traditional codes like SRW.

PMID:36601940 | DOI:10.1107/S1600577522010748

J Synchrotron Radiat. 2023 Jan 1;30(Pt 1):35-50. doi: 10.1107/S1600577522009973. Epub 2023 Jan 1.

ABSTRACT

A promising accelerator light source mechanism called steady-state microbunching (SSMB) is being actively studied. With the combination of strong coherent radiation from microbunching and high repetition rate of a storage ring, high-average-power narrow-band radiation can be anticipated from an SSMB storage ring, with wavelengths ranging from THz to soft X-ray. Such a novel light source could provide new opportunities for accelerator photon science like high-resolution angle-resolved photoemission spectroscopy and industrial applications like extreme ultraviolet (EUV) lithography. In this paper, a theoretical and numerical study of the average and statistical properties of coherent radiation from SSMB are presented. The results show that 1 kW average-power quasi-continuous-wave EUV radiation can be obtained from an SSMB ring provided that an average current of 1 A and a microbunch train with bunch length of 3 nm can be formed at the radiator which is assumed to be an undulator. Together with the narrow-band feature, the EUV photon flux can reach 6 × 10¹⁵ photons s^-1 within a 0.1 meV energy bandwidth, which is three orders of magnitude higher than that in a conventional synchrotron source and is appealing for fundamental condensed matter physics and other research. In this theoretical investigation, we have generalized the definition and derivation of the transverse form factor of an electron beam which can quantify the impact of its transverse size on coherent radiation. In particular, it has been shown that the narrow-band feature of SSMB radiation is strongly correlated with the finite transverse electron beam size. Considering the pointlike nature of electrons and quantum nature of radiation, the coherent radiation fluctuates from microbunch to microbunch, or for a single microbunch from turn to turn. Some important results concerning the statistical properties of SSMB radiation are presented, with a brief discussion on its potential applications, for example the beam diagnostics. The presented work is of value for the development of SSMB to better serve potential synchrotron radiation users. In addition, this also sheds light on understanding the radiation characteristics of free-electron lasers, coherent harmonic generation, etc.

PMID:36601924 | DOI:10.1107/S1600577522009973

Phlebology. 2023 Jan 5:2683555221149597. doi: 10.1177/02683555221149597. Online ahead of print.

ABSTRACT

BACKGROUND: Peripherally inserted central catheter (PICC) is widely used in clinical practice because of its long retention time and easy maintenance. However, PICC-associated venous thromboembolism (VTE) is the most serious complication of PICC. Guidelines recommend exercise therapy to prevent PICC-associated VTE. However, inconsistent findings have been reported across the literature. This study conducted a meta-analysis to further evaluate the effect of exercise therapy on PICC-associated VTE.

METHODS: We searched CNKI, Wanfang database, Chinese Science and Technology Journal Full Text Database, PubMed, Embase, Web of Science and Cochrane Library databases and included all randomized controlled trials (RCTs) of exercise therapy for the prevention of PICC-associated VTE. Two investigators independently screened the literature, extracted information, and evaluated the risk of bias for eligible RCTs. Meta-analysis was conducted by RevMan5.4 software.

RESULTS: Eleven RCTs were included, including 1919 patients. Meta-analysis showed that the incidence of PICC-associated VTE was lower in the exercise therapy group than in the usual care group (RR = 0.30, 95% CI: 0.22-0.41, p < 0.00001).Exercise therapy increased the axillary vein maximum velocity (SMD = 0.93, 95% CI: 0.58-1.28, p < 0.00001) and the axillary vein time-mean flow velocity (SMD = 0.86, 95% CI: 0.53-1.20, p < 0.00001). Subgroup analysis showed statistically significant differences for the incidence of PICC-associated VTE for intervention times<4 weeks (RR = 0.26, 95% CI: 0.17-0.40, p < 0.00001) and intervention times≥4 weeks (RR = 0.35, 95% CI: 0.22-0.54, p < 0.00001). For axillary vein maximum velocity, the difference was statistically significant for both intervention time <4 weeks (SMD = 0.73, 95% CI: 0.55-0.91, p < 0.00001) and intervention time ≥4 weeks (SMD = 1.18, 95% CI: 0.18-2.19, p = 0.02). For axillary vein time-mean flow velocity, the intervention time <4 weeks (SMD = 0.75, 95% CI: 0.46-1.04, p < 0.00001), and the difference was statistically significant; while ≥4 weeks, the difference was not statistically significant (SMD = 1.14, 95% CI: -0.07 to 2.35, p = 0.06).

CONCLUSIONS: Exercise therapy improved venous blood flow velocity and effectively reduced the incidence of PICC-associated VTE. However, RCTs with large samples and high quality are needed to further evaluate the effectiveness of exercise therapy in PICC patients.

PMID:36601900 | DOI:10.1177/02683555221149597

Pol Arch Intern Med. 2023 Jan 4:16395. doi: 10.20452/pamw.16395. Online ahead of print.

ABSTRACT

INTRODUCTION: The fracture risk assessment is essential for the diagnostic process in osteoporosis.

OBJECTIVE: The aim of the study was to develop an algorithm for fracture risk prediction.

PATIENTS AND METHODS: Bone status was investigated in a population-based cohort of postmenopausal women, their mean age being 66.4 (SD=7.8) years. After that all the participants were invited by phone once a year (for 10 consecutive years) to update their history of fractures. At the end of the 10-year observation period the number of the study participants was 640 women, out of whom, 129 women presented the history of 190 osteoporotic fractures, recorded during the study period. Statistical analysis included multistep data preprocessing, feature selection, identification of fracture risk factors, and a final model design. Logistic regression models were fitted and used for evaluation of variables from determined feature sets, including global fit measures, as well as individual parameters, such as the Wald statistic and P-value, the odds ratio, and the confidence interval.

RESULTS: The 10-year any fracture risk depended on the age of the study subjects, the number of recorded fractures after the age of 40 years, femoral neck bone mass values, and the fact of falls in the past year. The equation is as follows: Risk of fracture=1/(1+e^(-(-3.336+0.019*AGE+0.437*NUMBER_OF_PRIOR_FRACTURES-0.258*FN_T_score+0.508*PRIOR_FALLS)). The algorithm is available at www.fracture-risk.pl.

CONCLUSION: A fracture prediction algorithm was developed in a longitudinal study to calculate 10-year fracture risk. The identification of patients at high fracture risk should be followed by a treatment strategy to reduce the number of future fractures.

PMID:36601872 | DOI:10.20452/pamw.16395

Cancer Invest. 2023 Jan 5:1-8. doi: 10.1080/07357907.2022.2162072. Online ahead of print.

ABSTRACT

OBJECTIVE: To evaluate the diagnostic mismatch (discrepancy) of pathology reports in consulted specimens referred for second opinion.

MATERIALS AND METHODS: This cross-sectional study was conducted at a major cancer center, Omid Hospital. In this study, 350 primary pathology reports and 350 reviewed pathology reports were extracted from the archives of Omid Hospital from 2011 to 2020 and assessed in terms of the extent of discrepancy, by two pathologists and one oncologist. The required data for each sample were entered into a checklist and then statistically analyzed. Cases with the same diagnosis on both reports were assigned to the matched group and the rest were assigned to the minor or major mismatch (discrepancy) group. Minor mismatches included changes in diagnosis that did not lead to changes in treatment (may lead to changes in prognosis or provide additional information to the oncologist) and major mismatches included changes in diagnosis leading to changes in treatment or remedies.

RESULTS: Two hundred seven cases (59.1%) out of three hundred fifty cases had concordant results between the diagnosis of the first pathologist and the reviewing pathologist. In one hundred forty-three cases (40.9%) mismatch (discrepancy) was observed, including eighty- two cases (23.4%) with minor mismatches (discrepancy) and sixty-one cases (17.4%) with major mismatches (discrepancy). In the major mismatch group, fifteen cases (4.3%) changed from malignant to benign, eighteen cases (5.1%) changed from benign to malignant, two cases (0.6%) changed from one stage to another stage of Disease and twenty-six cases (7.4%) had changes in the type of malignancy. In this study, it was found that there was no significant relationship between anatomical areas of sampling and diagnostic mismatch (p = 0.254). The study also found that the rate of diagnostic mismatch in specimens obtained by resection or excisional biopsy was greater than that of small biopsies (eighty cases (22.8%) and sixty-two cases (17.7%, respectively)). There was no significant relationship in this regard (p = 0.077).

CONCLUSION: Compared to most similar studies, the present study reported the highest discrepancy between the diagnosis of the first pathologist and the reviewing pathologist (40.9%).

PMID:36601856 | DOI:10.1080/07357907.2022.2162072

Emerg Nurse. 2023 Jan 5. doi: 10.7748/en.2023.e2127. Online ahead of print.

ABSTRACT

Emergency triage is a short-duration, high-volume process so small reductions in the time taken to triage one patient can have large repercussions on the total amount of triage time. At the emergency department of a large inner-city hospital, an efficiency and quality improvement project was undertaken to reduce the time taken to safely triage patients and optimise the use of triage nurses’ time. The project involved removing processes that did not contribute to the primary aim of triage, supporting individual triage nurses to improve their performance where needed, and optimising the triage process. A 44% reduction in mean triage episode time was seen, equating to 18,000 minutes of triage nurses’ time saved every month. This near doubling of triage capacity was associated with an improvement in triage accuracy. The article describes the project, which used lean management principles and statistical process control methods, and discusses its implications for emergency triage.

PMID:36601815 | DOI:10.7748/en.2023.e2127

Acta Crystallogr D Struct Biol. 2023 Jan 1;79(Pt 1):50-65. doi: 10.1107/S2059798322011871. Epub 2023 Jan 1.

ABSTRACT

It is investigated whether molecular-dynamics (MD) simulations can be used to enhance macromolecular crystallography (MX) studies. Historically, protein crystal structures have been described using a single set of atomic coordinates. Because conformational variation is important for protein function, researchers now often build models that contain multiple structures. Methods for building such models can fail, however, in regions where the crystallographic density is difficult to interpret, for example at the protein-solvent interface. To address this limitation, a set of MD-MX methods that combine MD simulations of protein crystals with conventional modeling and refinement tools have been developed. In an application to a cyclic adenosine monophosphate-dependent protein kinase at room temperature, the procedure improved the interpretation of ambiguous density, yielding an alternative water model and a revised protein model including multiple conformations. The revised model provides mechanistic insights into the catalytic and regulatory interactions of the enzyme. The same methods may be used in other MX studies to seek mechanistic insights.

PMID:36601807 | DOI:10.1107/S2059798322011871

Acta Crystallogr D Struct Biol. 2023 Jan 1;79(Pt 1):31-39. doi: 10.1107/S2059798322011858. Epub 2023 Jan 1.

ABSTRACT

Proteins often assemble into functional complexes, the structures of which are more difficult to obtain than those of the individual protein molecules. Given the structures of the subunits, it is possible to predict plausible complex models via computational methods such as molecular docking. Assessing the quality of the predicted models is crucial to obtain correct complex structures. Here, an energy-scoring function was developed based on the interfacial residues of structures in the Protein Data Bank. The statistically derived energy function (Nepre) imitates the neighborhood preferences of amino acids, including the types and relative positions of neighboring residues. Based on the preference statistics, a program iNepre was implemented and its performance was evaluated with several benchmarking decoy data sets. The results show that iNepre scores are powerful in model ranking to select the best protein complex structures.

PMID:36601805 | DOI:10.1107/S2059798322011858

J Med Econ. 2023 Jan 5:1-15. doi: 10.1080/13696998.2023.2165365. Online ahead of print.

ABSTRACT

Background: Galcanezumab (GMB) improved quality of life and reduced disability of patients with episodic (EM) and chronic migraine (CM) in Phase 3 trials.Aim: To estimate indirect cost savings associated with GMB treatment in patients with migraine in the United States (US).Methods: We analyzed data of patients from the US from three randomized, Phase 3, double-blind, placebo (PBO)-controlled GMB studies: EVOLVE-1 and EVOLVE-2 (EM patients), REGAIN (CM patients). Annual indirect costs were calculated using items of Migraine Disability Assessment (MIDAS) questionnaire: lost time/productivity at work/school, household work, and leisure time. All costs were annualized and expressed in 2019 US dollars. While the main analysis considered lost time/productivity at work/school and household work as a full day, a sensitivity analysis was performed by discounting them by half. For EM, annual indirect costs savings were estimated using mixed model repeated measures analysis. For CM, ANCOVA models were used to estimate annual indirect costs savings as change from baseline.Results: The analysis included 805 patients with EM (mean age = 41.4y; PBO = 534; GMB = 271) and 423 patients with CM (mean age = 38.9y; PBO = 279; GMB = 144). Compared to PBO, GMB significantly reduced annual indirect costs among patients with EM at 3 months (least square mean [95% confidence interval] work/school=$1883.6 [603.64, 3163.65], p = 0.0040, household work=$628.9 [352.95, 904.88], p < 0.0001, and leisure activity=$499.17 [42.36, 955.98], p = 0.0323) and 6 months (work/school=$2382.29 [1065.48, 3699.10], p = 0.0004, household work=$559.45 [268.99, 849.90], p = 0.0002, and leisure activity=$753.81 [334.35, 1173.27], p = 0.0004), whereas significant difference was not observed among patients with CM. Sensitivity analysis results were similar to primary analysis results.Conclusions: GMB treatment versus PBO resulted in significantly greater indirect cost savings in patients with EM through improved productivity at work/school, household work, and leisure days. Patients with CM receiving GMB versus PBO attained greater cost savings, although not statistically significant, through reduced lost productivity at work/school.

PMID:36601798 | DOI:10.1080/13696998.2023.2165365

Biomed Chromatogr. 2023 Jan 5:e5578. doi: 10.1002/bmc.5578. Online ahead of print.

ABSTRACT

In this study, we utilized a serum metabolomics methodology based on gas chromatography coupled with mass spectrometry (GC/MS) to investigate the liver-protective effects of raw and stir-fried semens of Hovenia dulcis in rats models of carbon tetrachloride-induced liver injury. Multivariate statistical analysis, such as principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA), were conducted to examine changes in the metabolic state of rats with carbon tetrachloride-induced liver injury, as well as the recovery pattern of rats pretreated with the raw and stir-fried semens of Hovenia dulcis. Liver tissues were subjected to histopathological examination. A total of 47 biomarkers were predicted to contribute to the dynamic pathological processes in the liver injury, such as phenylalanine, glutamic acid, glycine, arachidonic acid and linoleic acid. Further analysis revealed that pathways associated with phenylalanine, tyrosine and tryptophan biosynthesis, and linoleic acid metabolism were altered in the injured liver, and that pretreatment with raw and stir-fried semens of Hovenia dulcis abolished the changes in the aforementioned metabolic pathways.

PMID:36601730 | DOI:10.1002/bmc.5578