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Doping quantum‐confined semiconductor nanocrystals offers an effective way to tailor their unique properties. However, the inherent challenges of nanoscale doping processes, such as the low probability of successful doping, have hindered their practical applications. Nucleation‐controlled doping has emerged as a potential solution, but a comprehensive mechanistic understanding of this process is lacking. Herein, the nucleation‐controlled doping process facilitated by magic‐sized cluster intermediates is elucidated. This approach enables the synthesis of 2D ZnSe quantum nanoribbons with two distinct doping sites. Remarkably, the identity of the dopants plays a critical role in determining the chemical pathways of nucleation‐controlled doping. Substitutional doping of magic‐sized clusters with Mn2+ ions leads to successful substitutional doping of the final 2D nanocrystals. Conversely, Co2+ ions, initially occupying substitutional positions in the magic‐sized cluster intermediates, relocate to alternative sites, such as interstitial sites, in the final nanocrystals. First‐principle calculations of dopant formation energies support these experimental findings, demonstrating the thermodynamic favorability of specific dopant site preferences. Moreover, a consistent tendency is observed in CdSe nanocrystals, suggesting that the proposed doping mechanism is generally applicable to II–VI semiconductors. This study will advance the controlled synthesis of various doped semiconductor nanocrystals using nucleation‐controlled doping processes. [ABSTRACT FROM AUTHOR]

Objective: The choice of voting methods has increasingly become a politicized, partisan issue. We ask: Can a nationalized partisan rhetoric cast doubt on vote‐by‐mail (VBM) despite years of experience and a raging pandemic? Method: Using 2020 general election records in Colorado, an established all‐mail voting state, we analyze first the general choice of voting methods using supervised machine learning and then the choice to switch to in‐person voting despite having used VBM in previous cycles. Results: The choice of voting modes is mainly habitual; local variations of COVID‐19 hardly mattered. Republican partisanship played an important role in predicting "switchers" to in‐person voting; the probability was 5.2 percent conditional on being a Republican as opposed to 1.9 percent for a Democrat. Conclusions: The results suggest that voting in person can be heavily polarized by partisan communication, despite being a health behavior in a pandemic and voters having experience with mail voting. [ABSTRACT FROM AUTHOR]

Understanding the mechanism underlying the formation of quantum‐sized semiconductor nanocrystals is crucial for controlling their synthesis for a wide array of applications. However, most studies of 2D CdSe nanocrystals have relied predominantly on ex situ analyses, obscuring key intermediate stages and raising fundamental questions regarding their lateral shapes. Herein, the formation pathways of two distinct quantum‐sized 2D wurtzite‐CdSe nanocrystals — nanoribbons and nanosheets — by employing a comprehensive approach, combining in situ small‐angle X‐ray scattering techniques with various ex situ characterization methods is studied. Although both nanostructures share the same thickness of ≈1.4 nm, they display contrasting lateral dimensions. The findings reveal the pivotal role of Se precursor reactivity in determining two distinct synthesis pathways. Specifically, highly reactive precursors promote the formation of the nanocluster‐lamellar assemblies, leading to the synthesis of 2D nanoribbons with elongated shapes. In contrast, mild precursors produce nanosheets from a tiny seed of 2D nuclei, and the lateral growth is regulated by chloride ions, rather than relying on nanocluster‐lamellar assemblies or Cd(halide)2–alkylamine templates, resulting in 2D nanocrystals with relatively shorter lengths. These findings significantly advance the understanding of the growth mechanism governing quantum‐sized 2D semiconductor nanocrystals and offer valuable guidelines for their rational synthesis. [ABSTRACT FROM AUTHOR]

Objective: Racial minority groups are often assumed to support equal opportunity policies, with most research focused on biracial contexts between Whites and Blacks. With a unique opportunity to study richer contexts from California's 2020 elections, we test whether Latino voters supported ballot measures associated with equal opportunity. Methods: Using data on vote choice for Propositions 15 (raising commercial property taxes) and 16 (repealing prohibition of affirmative action) from a post‐election survey of California registrants, we use logistic regression to test whether Latino support for equal opportunity policies is higher than that of Whites. Results: For both propositions, while Latino support was higher than White support, it was not statistically different when controlled for partisanship. Conclusion: There is little evidence to suggest that California Latinos support equal opportunity policies more strongly than White voters. This lukewarm support may explain the fates of both propositions in the election. [ABSTRACT FROM AUTHOR]

Objective: What can machine learning tell us about who voted in 2016? There are numerous competing voter turnout theories, and a large number of covariates are required to assess which theory best explains turnout. This article is a proof of concept that machine learning can help overcome this curse of dimensionality and reveal important insights in studies of political phenomena. Methods: We use fuzzy forests, an extension of random forests, to screen variables for a parsimonious but accurate prediction. Fuzzy forests achieve accurate variable importance measures in the face of high‐dimensional and highly correlated data. The data that we use are from the 2016 Cooperative Congressional Election Study. Results: Fuzzy forests chose only a small number of covariates as major correlates of 2016 turnout and still boasted high predictive performance. Conclusion: Our analysis provides three important conclusions about turnout in 2016: registration and voting procedures were important, political issues were important (especially Obamacare, climate change, and fiscal policy), but few demographic variables other than age were strongly associated with turnout. We conclude that fuzzy forests is an important methodology for studying overdetermined questions in social sciences. [ABSTRACT FROM AUTHOR]

Design of precursors for thin film growth by chemical vapor deposition (CVD) can be informed by knowledge of the precursor decomposition mechanism. However, the vast majority of decomposition characterization is done by techniques that do not capture CVD conditions. This work used a custom CVD reactor with in situ Raman spectroscopy capabilities to investigate the gas phase thermal decomposition of the tungsten imido complex Cl4(CH3CN)WNiPr, a known precursor for the aerosol‐assisted (AA)CVD of tungsten carbonitride thin films. In combination with previous computational and ex situ data, we propose a decomposition mechanism for this precursor under CVD conditions, based on observation of gas phase products of N(imido)‐C bond homolysis and σ‐bond metathesis between the precursor W–Cl bond and H2. [ABSTRACT FROM AUTHOR]

BSTRACT Purpose Diagnosis codes have been valid tools to identify severe neutropenia leading to hospitalization in claims data, but no data exist on the accuracy of outpatient diagnosis of neutropenia. We examined the validity and accuracy of claims-based algorithms to identify neutropenia from outpatient visits. Methods Adults with outpatient diagnosis of neutropenia in the HealthCore Integrated Research Database [ABSTRACT FROM AUTHOR]

Objective A novel rodent model and a recent randomized trial of hyperuricemic adolescents with hypertension suggest a pathogenetic role of uric acid in hypertension, but it remains unknown whether these findings would be applicable to adult populations where the larger disease burden exists. We conducted a systematic review and meta-analysis to determine if hyperuricemia was associated with incident hypertension, particularly in various demographic subgroups. Methods We searched major electronic databases using medical subject headings and keywords without language restrictions (through April 2010). We included prospective cohort studies with data on incident hypertension related to serum uric acid levels. Data abstraction was conducted in duplicate. We analyzed age, sex, and race subgroups. Results A total of 18 prospective cohort studies representing data from 55,607 participants were included. Hyperuricemia was associated with an increased risk for incident hypertension (adjusted risk ratio [RR] 1.41, 95% confidence interval [95% CI] 1.23-1.58). For a 1 mg/dl increase in uric acid level, the pooled RR for incident hypertension after adjusting for potential confounding was 1.13 (95% CI 1.06-1.20). These effects were significantly larger in younger study populations ( P = 0.02) and tended to be larger in women ( P = 0.059). Two studies suggested that the effect may also be larger among African American individuals. Furthermore, later publication year and US-based studies were significantly associated with a lower effect estimate ( P values <0.02). Conclusion Hyperuricemia is associated with an increased risk for incident hypertension, independent of traditional hypertension risk factors. This risk appears more pronounced in younger individuals and women. [ABSTRACT FROM AUTHOR]

The significance of lymphadenectomy in surgery for various kinds of cancer has been widely debated, particularly in the gynecological field. The cell wall skeleton of Mycobacterium bovis Bacillus Calmette-Guérin (BCG-CWS) has been used as an effective adjuvant for immunotherapy of a variety of cancer patients. Here we tested the immunological importance of lymph nodes in treatment of ovarian cancer patients with BCG-CWS. After surgical removal of tumors, 73 ovarian cancer patients were intracutaneously inoculated with BCG-CWS in the antigen-unloaded state in the upper arm at 4-week intervals at a dosage of 2–200 µg. Significant correlation of lymphadenectomy and reduced survival of patients was observed (stages I, II, III, IV; hazard ratio 2.38, 95% confidence interval 1.02–5.12, Cox regression model). Lymphadenectomy also compromised with induction of interferon-γ. In view of the importance of the role of lymph nodes in stimulation of Toll-like receptors by BCG-CWS, it is suggested that lymph nodes should be kept as much as possible to preserve the patient's immunity against cancer. Application of these results to surgery for other cancers should be considered. ( Cancer Sci 2009; 100: 1991–1995) [ABSTRACT FROM AUTHOR]

We investigated the antiproliferative effects of the cytoplasmic fraction of Lactococcus lactis ssp . lactis (L.lac CF) on the SNU-1 human stomach cancer cell line. The proliferation of SNU-1 cells was inhibited by treatment with L.lac CF in a time- and dose-dependent manner. L.lac CF caused G0/G1 cell cycle arrest, which was associated with an increase in p53 and p21 expression, the reduction of cyclin D1 expression, and retinoblastoma protein phosphorylation. L.lac CF induced apoptosis in SNU-1 cells, as demonstrated by increased nucleus condensation and a sub-G1 peak. Caspase-3 activation, the induction of p53, and the downregulation of Bcl-2 were also observed in L.lac CF-treated cells. Thus, the inhibitory effect of L.lac CF on SNU-1 cell growth is mainly attributable to the induction of G0/G1 cell cycle arrest and apoptosis. [ABSTRACT FROM AUTHOR]

Although non-scarring diffuse hair loss has been frequently observed in systemic lupus erythematosus (SLE) patients, the pattern of hair loss with regard to its frequency in SLE has been rarely studied. The aim of this cross-sectional study was to evaluate the hair loss patterns in SLE during the course of disease. We evaluated 122 SLE patients (age range, 13–71 years; mean age, 32.7 ± 10.6; female : male ratio, 12.6:1), by conducting interviews about hair loss patterns before and after a diagnosis of SLE using a questionnaire format. History taking and physical examinations were done at the time of interview, and photographs were taken to discriminate the active LE-specific scarring hair loss from the LE-nonspecific diffuse hair loss. Frequency and correlation analysis were performed on the data from the interviews and photographs for determining their relation with the SLE Disease Activity Index (SLEDAI). We found that 104 patients experienced at least one hair loss event before or during the course of SLE. Eighteen patients experienced patch alopecia, including eight who experienced this malady both before and after the diagnosis; thus, the overall prevalence of patch alopecia was 14.8% (18/122). Eighty-six patients experienced hair loss after diagnosis, of which non-scarring diffuse hair loss was the most common pattern (65.1%, 56/86) followed by non-scarring patch alopecia (15.1%, 13/86). The interview survey failed to identify a statistically significant relationship between the hair loss pattern and the SLEDAI. Our results suggest that non-scarring patch alopecia is also an important pattern in SLE that should be included in the differential diagnosis of alopecia areata and confirmed by histopathological examination. [ABSTRACT FROM AUTHOR]

Abstract: The effect of surfactin on the proliferation of LoVo cells, a human colon carcinoma cell line, was examined. Surfactin strongly blocked the proliferation of LoVo cells by inducing pro-apoptotic activity and arresting the cell cycle, according to several lines of evidence on DNA fragmentation, Annexin V staining, and altered levels of poly (ADP-ribose) polymerase, caspase-3, p21WAF1/Cip1, p53, CDK2 and cyclin E. The anti-proliferative activity of surfactin was mediated by inhibiting extracellular-related protein kinase and phosphoinositide 3-kinase/Akt activation, as assessed by phosphorylation levels. Therefore, our data suggest that surfactin may have anti-cancer properties as a result of its ability to downregulate the cell cycle and suppress its survival. [Copyright &y& Elsevier]

Considerable attention has recently been focused on identifying chemopreventive phytochemicals derived from medicinal plants. Here, we analyzed phenolic phytochemicals from red pine (RP) leaves and found epigallocatechin gallate (EGCG) and epigallocatechin (EGC), and catechin gallate (CG) as their major phenolic phytochemicals. This article also investigated whether RP leaf extract and its phenolic phytochemicals inhibit the invasion of SK-Hep-1 human hepatocellular carcinoma cells (SK-Hep-1 cells). RP suppressed the invasion and the migration of SK-Hep-1 cells. EGCG and CG also inhibited the invasion and migration, with EGC exhibiting a lower efficacy. Matrix metalloproteinases (MMPs), particularly gelatinase-A (MMP-2) and gelatinase-B (MMP-9), degrade components of the basement membrane and are strongly implicated in invasion and metastasis formation of malignant tumors. RP suppressed both MMP-2 and MMP-9 activities. EGCG and CG reduced the activities of MMP-9 and MMP-2 in a dose-dependent manner, with EGC exhibiting a lower efficacy on both MMPs. Our results suggest that RP inhibits tumor invasion and migration, which may be attributed to the effects of EGCG and CG. In particular, EGCG plays a key role in the efficacy of RP against hepatocarcinogenesis. [ABSTRACT FROM AUTHOR]

Seahorses, Hippocampus abdominalis, have a long history in traditional Chinese medicine as an important healthy ingredient in foods. This study evaluated the antioxidant activity of an enzymatic hydrolysate prepared from a seahorse bred in Jeju, South Korea. Experiments were performed in vitro using electron spin resonance spectrometry (ESR) to determine the free radical scavenging activity and in vivo using a zebrafish model to determine the protective effects against 2,2‐azobis hydrochloride (AAPH)‐induced oxidative damage. H. abdominalis protein hydrolysate (HPH) exhibited peroxyl radical scavenging activity (IC50 = 0.58 mg/ml) generated by the water‐soluble AAPH (azo initiator of peroxyl radicals). HPH reduced dose‐dependently both intracellular reactive oxygen species (ROS) levels in AAPH‐induced cells and cell death in AAPH‐induced zebrafish embryos. The antioxidant peptide purified from HPH was identified as a tripeptide (alanine–glycine–aspartic acid) using Q‐TOF ESI mass spectroscopy. Thus, this study demonstrated that HPH contains antioxidant peptides that exhibit a strong antioxidant activity. Practical applications: Hippocampus abdominalis is one of the largest seahorse species and cultivated in many countries. Because of its large body size compared to other seahorse species, H. abdominalis has acquired considerable consumer attraction in the global market. Owing to its biologically useful properties, it recently gained attention as the natural products obtained from H. abdominalis have varied applications in the field of medicine, health care products, and functional foods. Thus, commercial products of this particular seahorse species are popular among customers, especially in China. The purpose of this study was to evaluate the antioxidant property of H. abdominalism, cultured in a commercial seahorse farm in Jeju Island. Owing to its prominent antioxidant activity, it could be used as an ingredient in medicinal preparations, nutraceuticals, and functional foods. [ABSTRACT FROM AUTHOR]

Objective: To assess the association between hyperuricemia and risk of stroke incidence and mortality because hyperuricemia is hypothesized to be a risk factor for stroke and other cardiovascular disease, but, to date, results from observational studies are conflicting., Methods: A systematic review and meta-analysis were conducted. Studies were identified by searching major electronic databases using the Medical Subject Headings and keywords without restriction in languages. Prospective cohort studies were included only if they contained data on stroke incidences or mortalities related to serum uric acid levels in adults. Pooled risk ratios (RRs) for the association of stroke incidence and mortality with serum uric acid levels were calculated., Results: A total of 16 studies including 238,449 adults were eligible and abstracted. Hyperuricemia was associated with a significantly higher risk of both stroke incidence (6 studies; RR 1.41, 95% confidence interval [95% CI] 1.05, 1.76) and mortality (6 studies; RR 1.36, 95% CI 1.03, 1.69) in our meta-analyses of unadjusted study estimates. Subgroup analyses of studies adjusting for known risk factors such as age, hypertension, diabetes mellitus, and cholesterol still showed that hyperuricemia was significantly associated with both stroke incidence (4 studies; RR 1.47, 95% CI 1.19, 1.76) and mortality (6 studies; RR 1.26, 95% CI 1.12, 1.39). The pooled estimate of multivariate RRs did not differ significantly by sex., Conclusion: Hyperuricemia may modestly increase the risks of both stroke incidence and mortality. Future research is needed to determine whether lowering uric acid level has any beneficial effects on stroke.