Tag: pubmed

PLoS One. 2021 Jul 21;16(7):e0254933. doi: 10.1371/journal.pone.0254933. eCollection 2021.

ABSTRACT

Physical objects and their pictures are two main kinds of design stimuli of creative activity, which can improve design quality but may induce design fixation. Previous studies are focused on the case where participants face a single picture, and their design stimulus may be incomplete as compared with the participants facing objects. To fully explore the influence of physical and pictorial examples on design novices, we investigated design fixation and design quality when they were provided with multiperspective pictures having information remarkably similar to physical objects. Specifically, two novice groups individually created their own designs after observing several examples by the way of the above two presentation modes. These designs were evaluated by two evaluators in terms of similarity, originality, and completeness. Statistical analysis showed that no significant difference was found in similarity and originality between the two groups, whereas the designs of the physical group outperformed those of the pictorial group in terms of completeness. This finding indicated that the two groups showed the same degree of design fixation, as multiperspective pictures presented most of the form information of the physical object. The results suggest that when instructing design novices, it is essential to control how to present design examples at different stages of the design process.

PMID:34288942 | DOI:10.1371/journal.pone.0254933

PLoS One. 2021 Jul 21;16(7):e0254926. doi: 10.1371/journal.pone.0254926. eCollection 2021.

ABSTRACT

Substance abuse is a major concern worldwide and is increasing rapidly in Bangladesh. However, there are no prior studies concerning lifestyle-related factors that influence adolescents’ substance use behavior. Therefore, the present study investigated the prevalence of substance use and its associated sociodemographic and lifestyle-related risk factors among a total of 424 Bangladeshi high school-going adolescents through a structured questionnaire interview study. The survey questionnaire consisted of socio-demographics, lifestyle-related information, and substance use-related questions. For data analysis, descriptive and inferential statistics were performed using SPSS (Statistical Package for Social Science) version 22.0, and a p-value of <0.05 determined statistical significance. Results showed that 21.2%, 14.4%, and 15.1% of the participants reported smoking, using a drug, and consuming alcohol, respectively, at least once during their lifespan; whereas the current (i.e., past-month) rates were reported to be 10.4%, 2.8%, and 3.1%, respectively. Overall, the current substance use risk factors were identified as being male, not being from science academic background, having less family influence on personal life, irregular teeth brushing, being smartphone users, using a smartphone for a longer time, and being late-night sleepers. From the list of identified risk factors of substance use, those that are modifiable may be targeted to evolve a prevention program to manage this problem in Bangladeshi adolescents.

PMID:34288956 | DOI:10.1371/journal.pone.0254926

PLoS One. 2021 Jul 21;16(7):e0254811. doi: 10.1371/journal.pone.0254811. eCollection 2021.

ABSTRACT

We derive a noncentral [Formula: see text] power approximation for the Kenward and Roger test. We use a method of moments approach to form an approximate distribution for the Kenward and Roger scaled Wald statistic, under the alternative. The result depends on the approximate moments of the unscaled Wald statistic. Via Monte Carlo simulation, we demonstrate that the new power approximation is accurate for cluster randomized trials and longitudinal study designs. The method retains accuracy for small sample sizes, even in the presence of missing data. We illustrate the method with a power calculation for an unbalanced group-randomized trial in oral cancer prevention.

PMID:34288958 | DOI:10.1371/journal.pone.0254811

Microsc Res Tech. 2021 Jul 19. doi: 10.1002/jemt.23878. Online ahead of print.

ABSTRACT

The purpose of this in vitro study was to evaluate the effect of immediate dentin sealing (IDS) with and without chlorhexidine (CHX) pretreatment on the shear bond strength (SBS) of dual-cure adhesive resin cement. Mid-coronal dentin surfaces were obtained from 75 human molars. They were randomly allocated into five groups in accordance to type of IDS [etch&rinse/ER (Adper Single Bond2) and universal/U adhesive systems (Single Bond Universal)] and presence of CHX application (n = 15): Group ER; Group ER + CHX; Group U; Group U + CHX; and Group C (no IDS). Dual-cure adhesive resin cements were bonded with a cylinder-shaped Teflon mold. The SBS was measured using a universal test machine. Fracture type was evaluated with stereomicroscope. The resin/dentin interfaces were examined with an environmental scanning electron microscope. Data were statistically analyzed with two-way analysis of variance and Bonferroni tests (p < .05). Regarding the IDS treatment groups with/without CHX, there were no significant differences in SBS (p > .05). Group U + CHX showed significantly higher SBS than Group C (p < .05). Regarding the presence of CHX, no significant differences in SBS were found (p > .05). The prevalent failure mode was the mixed type for most of the groups. Group C exhibited an intact and regular hybrid layer with no resin tag, whereas longer and clear resin-tag formation was visible for Group U + CHX. CHX pretreatment improved the bond strength between adhesive resin cement and dentin when IDS treatment was performed with a universal adhesive system.

PMID:34286901 | DOI:10.1002/jemt.23878

Dalton Trans. 2021 Jul 21. doi: 10.1039/d1dt01754c. Online ahead of print.

ABSTRACT

Computational methods have emerged as a powerful tool to augment traditional experimental molecular catalyst design by providing useful predictions of catalyst performance and decreasing the time needed for catalyst screening. In this perspective, we discuss three approaches for computational molecular catalyst design: (i) the reaction mechanism-based approach that calculates all relevant elementary steps, finds the rate and selectivity determining steps, and ultimately makes predictions on catalyst performance based on kinetic analysis, (ii) the descriptor-based approach where physical/chemical considerations are used to find molecular properties as predictors of catalyst performance, and (iii) the data-driven approach where statistical analysis as well as machine learning (ML) methods are used to obtain relationships between available data/features and catalyst performance. Following an introduction to these approaches, we cover their strengths and weaknesses and highlight some recent key applications. Furthermore, we present an outlook on how the currently applied approaches may evolve in the near future by addressing how recent developments in building automated computational workflows and implementing advanced ML models hold promise for reducing human workload, eliminating human bias, and speeding up computational catalyst design at the same time. Finally, we provide our viewpoint on how some of the challenges associated with the up-and-coming approaches driven by automation and ML may be resolved.

PMID:34286781 | DOI:10.1039/d1dt01754c

Echocardiography. 2021 Jul 19. doi: 10.1111/echo.15160. Online ahead of print.

ABSTRACT

BACKGROUND: Coronavirus 2019 (COVID-19) causes morbidity and mortality in an increasing number of people worldwide. Although it mainly affects the respiratory system, it influences all organs, including the heart. It is associated with a broad spectrum of widespread cardiovascular problems ranging from mild myocardial injury to fulminant myocarditis. We aimed to evaluate the presence and prevalence of cardiac involvement in asymptomatic or symptomatic patients after they recovered from COVID 19 infection.

METHODS: A total of 100 consecutive patients with COVID-19 proven by reverse transcription polymerase chain reaction (RT-PCR), under 40 years of age and without any known additional chronic diseases were analyzed retrospectively for cardiac magnetic resonance (CMR) results and symptoms.

RESULTS: Cardiac involvement was detected in 49 out of 100 patients on CMR imaging. In the cardiac involvement group, the number of patients with chest pain and/or dyspnea was 41 (84%), which was statistically significant (p = 0.001). Twenty-four patients (47%) in the without cardiac involvement group were asymptomatic and this was also statistically significant (p = 0.001). LV ejection fraction was statistically significantly lower in the group with cardiac involvement (61% vs 66%, p = 0.001). LV stroke volume and tricuspid annular plane systolic excursion (TAPSE) were statistically significantly lower in patients with cardiac involvement (p = 0.028 and p = 0.019, respectively).

CONCLUSION: Based on single center experience, myocardial involvement is common in symptomatic patients after COVID-19. More studies are needed for long-term side effects and clinical results in these patients.

PMID:34286876 | DOI:10.1111/echo.15160

Addiction. 2021 Jul 19. doi: 10.1111/add.15642. Online ahead of print.

ABSTRACT

BACKGROUND AND AIMS: Money is central to psychological definitions of gambling, but contemporary accounts are ambiguous regarding the role of financial motives in disordered gambling. The aims of the current research were to obtain meta-analytic weighted effect sizes for zero-order associations of financial motives against gambling frequency and level of problem gambling, as well as partial associations after controlling for other motives (e.g., coping).

METHODS: A meta-analysis of the literature through February 2021 was undertaken. Studies were identified from multiple sources (e.g., database search, other researchers). PRISMA standards were followed when screening identified records and extracting relevant data. The data analytic plan was pre-registered. We included 44 cross-sectional studies that involved student, community, and clinical samples of people who gamble (sample sizes ranged from 22 to 5,666), using validated self-report measures of financial gambling motives alongside measures of either gambling frequency and/or problem gambling.

RESULTS: Financial gambling motives were positively associated with gambling frequency, r = .29, [.21, .37], N= 22,738 and level of problem gambling, r = .35, [.31, .38], N = 38,204 with moderate effect sizes. Partial associations after controlling for overlapping variance with other gambling motives were also positive (gambling frequency: β = .14, [.05, .22], N = 13,844; level of problem gambling: β = .18, [.13, .22], N = 28,146), with small-to-moderate effect sizes. Effect sizes were heterogeneous and the extent of heterogeneity was high. Analyses of the zero-order association involving gambling frequency indicated that gambling motives measure (greater for Gambling Motives Questionnaire-Financial) and sample mean age (greater for younger samples) were moderators. No other moderators were statistically significant.

CONCLUSIONS: Financial gambling motives appear to be reliably and positively associated with both gambling frequency and level of problem gambling.

PMID:34286879 | DOI:10.1111/add.15642

J Biomol Struct Dyn. 2021 Jul 21:1-19. doi: 10.1080/07391102.2021.1953604. Online ahead of print.

ABSTRACT

Comparative functional analysis of the dynamic interactions between various Betacoronavirus mutant strains and broadly utilized target proteins such as ACE2 and CD26, is crucial for a more complete understanding of zoonotic spillovers of viruses that cause diseases such as COVID-19. Here, we employ machine learning to replicated sets of nanosecond scale GPU accelerated molecular dynamics simulations to statistically compare and classify atom motions of these target proteins in both the presence and absence of different endemic and emergent strains of the viral receptor binding domain (RBD) of the S spike glycoprotein. A multi-agent classifier successfully identified functional binding dynamics that are evolutionarily conserved from bat CoV-HKU4 to human endemic/emergent strains. Conserved dynamics regions of ACE2 involve both the N-terminal helices, as well as a region of more transient dynamics encompassing residues K353, Q325 and a novel motif AAQPFLL 386-92 that appears to coordinate their dynamic interactions with the viral RBD at N501. We also demonstrate that the functional evolution of Betacoronavirus zoonotic spillovers involving ACE2 interaction dynamics are likely pre-adapted from two precise and stable binding sites involving the viral bat progenitor strain’s interaction with CD26 at SAMLI 291-5 and SS 333-334. Our analyses further indicate that the human endemic strains hCoV-HKU1 and hCoV-OC43 have evolved more stable N-terminal helix interactions through enhancement of an interfacing loop region on the viral RBD, whereas the highly transmissible SARS-CoV-2 variants (B.1.1.7, B.1.351 and P.1) have evolved more stable viral binding via more focused interactions between the viral N501 and ACE2 K353 alone.Communicated by Ramaswamy H. Sarma.

PMID:34286673 | DOI:10.1080/07391102.2021.1953604

Anal Methods. 2021 Jul 21. doi: 10.1039/d1ay00430a. Online ahead of print.

ABSTRACT

High-resolution continuum source graphite furnace molecular absorption spectrometry (HR-CS-GF-MAS) was employed for determining adsorbable organic chlorine (AOCl) in water. Organic chlorine was indirectly quantified by monitoring the molecular absorption of the transient aluminum monochloride molecule (AlCl) around a wavelength of 261.42 nm in a graphite furnace. An aluminum solution was used as the molecular-forming modifier. A zirconium coated graphite furnace, as well as Sr and Ag solutions were applied as modifiers for a maximal enhancement of the absorption signal. The pyrolysis and vaporization temperatures were 600 °C and 2300 °C, respectively. Non-spectral interferences were observed with F, Br, and I at concentrations higher than 6 mg L-1, 50 mg L-1, and 100 mg L-1, respectively. Calibration curves with NaCl, 4-chlorophenol, and trichlorophenol present the same slope and dynamic range, which indicates the chlorine atom specificity of the method. This method was evaluated and validated using synthetic water samples, following the current standard DIN EN ISO 9562:2004 for the determination of the sum parameter adsorbable organic halides (AOX) for water quality. These samples contain 4-chlorophenol as the chlorinated organic standard in an inorganic chloride matrix. Prior to analysis, organic chlorine was extracted from the inorganic matrix via solid-phase extraction with a recovery rate >95%. There were no statistically significant differences observed between measured and known values and for a t-test a confidence level of 95% was achieved. The limits of detection and characteristic mass were found to be 48 and 22 pg, respectively. The calibration curve was linear in the range 0.1-2.5 ng with a correlation coefficient R2 = 0.9986.

PMID:34286717 | DOI:10.1039/d1ay00430a

Ann Hum Biol. 2021 Jul 21:1-24. doi: 10.1080/03014460.2021.1957501. Online ahead of print.

ABSTRACT

BACKGROUND: According to numerous studies from around the world, semen quality seems to have declined dramatically over the last years. However, the data investigated on male fertility status and semen quality in North Africa is limited.

AIM: To investigate on the status of semen quality in North-African men and to understand its variations.

SUBJECTS & METHODS: 20,958 Sperm-analyses (Spermogram – Spermocytogram) of North-African men (19-77 years old) consulting for infertility, performed in a private laboratory of medical analyses (Tunis, Tunisia) over a period of six years (2013 – 2018), were investigated. All patients had at least one year of unprotected intercourse with their partners before the test. Statistical analyses were performed using SPSS 22.0 software for windows.

RESULTS: Libyan men presented a clear decline in all sperm parameters. A continuous decline in sperm morphology quality was shown in Tunisian and Algerian men. Mauritanian men presented a significant increase in sperm vitality with pseudo-stability in the rest of sperm parameters during the whole study period.

CONCLUSION: North-African men presented remarkable decreases of their semen quality over the last decade. This data could confirm possible global common-causes that need to be identified in order to limit their negative impact on sperm quality, and consequently on male-fertility.

PMID:34286659 | DOI:10.1080/03014460.2021.1957501