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The pursuit of unhealthy behaviors, such as smoking or binge drinking, not only carries various downside risks, but also provides pleasure. A parsimonious model, used in the literature to explain the decision to pursue an unhealthy activity, represents that decision as a tradeoff between risks and benefits. We build on this literature by surveying a rural population in South Africa to elicit the perceived riskiness and the perceived pleasure for various risky activities and to examine how these perceptions relate to the pursuit of four specific unhealthy behaviors: frequent smoking, problem drinking, seatbelt nonuse, and risky sex. We show that perceived pleasure is a significant predictor for three of the behaviors and that perceived riskiness is a significant predictor for two of them. We also show that the correlation between the riskiness rating and behavior is significantly different from the correlation between the pleasure rating and behavior for three of the four behaviors. Finally, we show that the effect of pleasure is significantly greater than the effect of riskiness in determining drinking and risky sex, while the effects of pleasure and riskiness are not different from each other in determining smoking and seatbelt nonuse. We discuss how our findings can be used to inform the design of health promotion strategies.
This study is performed to figure out how the presence of diabetes affects the infection, progression and prognosis of 2019 novel coronavirus disease (COVID-19), and the effective therapy that can treat the diabetes-complicated patients with COVID-19. A multicentre study was performed in four hospitals. COVID-19 patients with diabetes mellitus (DM) or hyperglycaemia were compared with those without these conditions and matched by propensity score matching for their clinical progress and outcome. Totally, 2444 confirmed COVID-19 patients were recruited, from whom 336 had DM. Compared to 1344 non-DM patients with age and sex matched, DM-COVID-19 patients had significantly higher rates of intensive care unit entrance (12.43% vs. 6.58%, P = 0.014), kidney failure (9.20% vs. 4.05%, P = 0.027) and mortality (25.00% vs. 18.15%, P < 0.001). Age and sex-stratified comparison revealed increased susceptibility to COVID-19 only from females with DM. For either non-DM or DM group, hyperglycaemia was associated with adverse outcomes, featured by higher rates of severe pneumonia and mortality, in comparison with non-hyperglycaemia. This was accompanied by significantly altered laboratory indicators including lymphocyte and neutrophil percentage, C-reactive protein and urea nitrogen level, all with correlation coefficients >0.35. Both diabetes and hyperglycaemia were independently associated with adverse prognosis of COVID-19, with hazard ratios of 10.41 and 3.58, respectively.
Extensive magmatism in NE China, eastern Central Asian Orogenic Belt, has produced multi-stage granitic plutons and accompanying W mineralization. The Narenwula complex in the southwestern Great Xing’an Range provides important insights into the petrogenesis, geodynamic processes and relationship with W mineralization. The complex comprises granodiorites, monzogranites and granite porphyry. Mafic microgranular enclaves are common in the granodiorites, and have similar zircon U–Pb ages as their host rocks (258.5–253.9 Ma), whereas the W-bearing granitoids yield emplacement ages of 149.8–148.1 Ma. Permian granodiorites are I-type granites that are enriched in large-ion lithophile elements and light rare earth elements, and depleted in high field strength elements and heavy rare earth elements. Both the mafic microgranular enclaves and granodiorites have nearly identical zircon Hf isotopic compositions. The results suggest that the mafic microgranular enclaves and granodiorites formed by the mixing of mafic and felsic magmas. W-bearing granitoids are highly fractionated A-type granites, enriched in Rb, Th, U and Pb, and depleted in Ba, Sr, P, Ti and Eu. They have higher W concentrations and Rb/Sr ratios, and lower Nb/Ta, Zr/Hf and K/Rb ratios than the W-barren granodiorites. These data and negative ϵHf(t) values (–6.0 to –2.1) suggest that they were derived from the partial melting of ancient lower crust and subsequently underwent extreme fractional crystallization. Based on the regional geology, we propose that the granodiorites were generated in a volcanic arc setting related to the subduction of the Palaeo-Asian Ocean, whereas the W-bearing granitoids and associated deposits formed in a post-orogenic extensional setting controlled by the Mongol–Okhotsk Ocean and Palaeo-Pacific Ocean tectonic regimes.
Deficits in event-related potential (ERP) including duration mismatch negativity (MMN) and P3a have been demonstrated widely in chronic schizophrenia (SZ) but inconsistent findings were reported in first-episode patients. Psychotropic medications and diagnosis might contribute to different findings on MMN/P3a ERP in first-episode patients. The present study examined MMN and P3a in first episode drug naïve SZ and bipolar disorder (BPD) patients and explored the relationships among ERPs, neurocognition and global functioning.
Twenty SZ, 24 BPD and 49 age and sex-matched healthy controls were enrolled in this study. Data of clinical symptoms [Positive and Negative Symptoms Scale (PANSS), Young Manic Rating Scale (YMRS), Hamilton Depression Rating Scale (HAMD)], neurocognition [Wechsler Adult Intelligence Scale (WAIS), Cattell's Culture Fair Intelligence Test (CCFT), Delay Matching to Sample (DMS), Rapid Visual Information Processing (RVP)], and functioning [Functioning Assessment Short Test (FAST)] were collected. P3a and MMN were elicited using a passive auditory oddball paradigm.
Significant MMN and P3a deficits and impaired neurocognition were found in both SZ and BPD patients. In SZ, MMN was significantly correlated with FAST (r = 0.48) and CCFT (r = −0.31). In BPD, MMN was significantly correlated with DMS (r = −0.54). For P3a, RVP and FAST scores were significant predictors in SZ, whereas RVP, WAIS and FAST were significant predictors in BPD.
The present study found deficits in MMN, P3a, neurocognition in drug naïve SZ and BPD patients. These deficits appeared to link with levels of higher-order cognition and functioning.
Hypertension represents one of the most common pre-existing conditions and comorbidities in Coronavirus disease 2019 (COVID-19) patients. To explore whether hypertension serves as a risk factor for disease severity, a multi-centre, retrospective study was conducted in COVID-19 patients. A total of 498 consecutively hospitalised patients with lab-confirmed COVID-19 in China were enrolled in this cohort. Using logistic regression, we assessed the association between hypertension and the likelihood of severe illness with adjustment for confounders. We observed that more than 16% of the enrolled patients exhibited pre-existing hypertension on admission. More severe COVID-19 cases occurred in individuals with hypertension than those without hypertension (21% vs. 10%, P = 0.007). Hypertension associated with the increased risk of severe illness, which was not modified by other demographic factors, such as age, sex, hospital geological location and blood pressure levels on admission. More attention and treatment should be offered to patients with underlying hypertension, who usually are older, have more comorbidities and more susceptible to cardiac complications.
Parabronema skrjabini is one of the most harmful nematodes to camels and is responsible for economic losses in animal husbandry industry. There is an urgent need for in-depth studies of potential vectors of the nematode due to its scant regarding information. As previous studies indicated that flies may be the vectors of P. skrjabini, we captured flies in the main camel-producing areas of Inner Mongolia. After autopsy of the specimens of two species of horn flies, we observed the morphology of the suspected nematode larvae found in them. Internal transcribed spacer ribosomal-DNA gene sequences were considered the best candidate to confirm the species of the larvae found. Our results showed that the homology compared with P. skrjabini was 99.5% in GenBank. Subsequently, we preliminarily identified two species of horn flies through morphological observation and then sequenced the mitochondrial-DNA-gene cytochrome oxidase subunit I obtained from two species of horn flies, with 100 and 99.2% similarity to sequences deposited in GenBank, respectively. Thus, we identified Haematobia titillans and Haematobia irritans and provided evidence for their potential role as vectors of parabronemosis. Our study provides reference for future research on the life history of the nematode and the vectors of parabronemosis.
Several studies have suggested that higher carotenoid levels may be beneficial for atherosclerosis patients, but few studies have examined this relationship in the Chinese population. This cross-sectional study examined the association between the levels of carotenoids in diet and serum and carotid intima–media thickness (IMT) in Chinese adults aged 50–75 years in Guangzhou, China. Dietary intake was assessed using a FFQ. HPLC was used to assay the serum concentrations of α-carotene, β-carotene, lutein+zeaxanthin, β-cryptoxanthin and lycopene. The IMT at the common carotid artery (CCA) and bifurcation of the carotid artery was measured by B-mode ultrasound. A total of 3707 and 2947 participants were included in the analyses of dietary and serum carotenoids. After adjustment for demographic, socio-economic and lifestyle factors, all the serum carotenoids levels except lycopene were found to be inversely associated with the IMT at the CCA and bifurcation (Ptrend<0·001 to 0·013) in both men and women. The absolute mean differences in the IMT between the subjects in the extreme quartiles of serum carotenoid levels were 0·034 mm (α-carotene), 0·037 mm (β-carotene), 0·032 mm (lutein+zeaxanthin), 0·030 mm (β-cryptoxanthin), 0·015 mm (lycopene) and 0·035 mm (total carotenoids) at the CCA; the corresponding values were 0·025, 0·053 0·043, 0·050, 0·011 and 0·042 mm at the bifurcation. The favourable associations were also observed between dietary carotenoids (except lycopene) and the CCA IMT. In conclusion, elevated carotenoid levels in diet and serum are associated with lower carotid IMT values (particular at the CCA) in Chinese adults.
Freedom from fear and freedom from want are two of the fundamental freedoms and likely related to changes in the environment. It has usually been assumed that our subjective feelings should change accordingly with changes in the objective environment. However, two counterintuitive effects reviewed in this article imply a rather complex psychological mechanism behind how people respond to environmental changes and strive for the freedom from fear and want. The first is the ‘psychological typhoon eye’ effect, in which the closer people are to hazards, the calmer they feel. Several possible explanations have been proposed, but the mechanism behind this effect remains unclear. The findings are important for future post-disaster interventions and helpful for policy makers in risk management and researchers in risk studies. The second effect is the ‘town dislocation’ effect, wherein although inhabitants’ objective quality of life is improved during the urbanisation process, the projected endorsement and rated social ambience of town residents is lower than that of residents in the country and in the city; this effect is mediated by social support. The findings have implications for how to better assess the urbanisation process and how to improve people's affective appraisals of their living environment.
The Lorentz factor (Γ) is an important parameter related to the relativistic jet physics. We study the evolution patterns of Γ within gamma-ray burst (GRB) and active galactic nuclear jets for individual GRB 090168, GRB 140508A, and 3C 454.3. By estimating the Γ values for well-separated pulses in GRBs 090618 and 140508A with an empirical relation derived from typical GRBs, we find that the Γ evolution pattern in the two GRBs are different. The increasing-to-coasting evolution pattern of Γ in GRB 090618 likely indicates that the GRB fireball is still being accelerated in the prompt phase. The clear decrease evolution pattern of Γ in GRB 140508A suggests the deceleration of the fireball components. By deriving the Γ value through fitting their spectral energy distribution in different flares of 3C 454.3, a pattern of Γ-tracking-γ-ray flux is clearly found, likely indicating that the observed gamma-ray flares are being due to the Doppler boosting effect to the jet emission.
Results of the relationships between dietary whole-grain consumption and the risk of all-cause, CVD and cancer-specific mortality are mixed. We summarised the evidence based on a meta-analysis of prospective cohort studies. Pertinent studies were identified by searching articles in the MEDLINE and EMBASE databases up to 20 January 2016 and by reviewing the reference lists of the retrieved articles. Random-effects models were used to calculate summary relative risks (SRR) and 95 % CI. In all, eleven prospective studies (ten publications) were included in the meta-analysis. There were a total of 816 599 subjects and 89 251 cases of all-cause mortality. On the basis of the highest v. the lowest categories of intake, whole grains may be associated with a lower risk of mortality from all causes (SRR 0·87; 95 % CI 0·84, 0·90), CVD (SRR 0·81; 95 % CI 0·75, 0·89) and all cancers (SRR 0·89; 95 % CI 0·82, 0·96). For each 3 servings/d increase in whole-grain intake, there was a 19 % reduction in the risk of all-cause mortality (SRR 0·81; 95 % CI 0·76, 0·85), a 26 % reduction in CVD mortality (SRR 0·74; 95 % CI 0·66, 0·83) and a 9 % reduction in cancer mortality (SRR 0·91; 95 % CI 0·84, 0·98). The current meta-analysis provides some evidence that high intake of whole grains was inversely associated with the risk of all-cause, CVD and cancer-specific mortality. Further well-designed studies, including clinical trials and in different populations, are required to confirm our findings.
Allocetraria yunnanensis R. F. Wang, X. L. Wei & J. C. Wei is described as a new species from the Yunnan Province of China, and is characterized by having a shiny upper surface, strongly wrinkled lower surface, and marginal pseudocyphellae present on the lower side in the form of a white continuous line or spot. The phylogenetic analysis based on nrDNA ITS sequences suggests that the new species is related to A. sinensis X. Q. Gao.
In this paper, the hole carrier mobility of organic semiconductor N,N′-diphenyl-N,N′bis(1,1′-biphenyl)-4,4′-diamine (NPD) was researched by negative differential susceptance spectra (−ΔB = −w(C − Cgeo) ~ f). Under the condition of space charge limited current (SCLC), through solving the drift current equation and Poisson equation and simulating the spectra −ΔB = −w(C − Cgeo) ~ f, the relationship between the peak of −ΔB = −w(C − Cgeo) ~ f spectra (1/ƒp = τp) and the transfer time of carrier (τdc) could be achieved to be τdc = k × τp. So the hole-only device of ITO/NPD/Ag was fabricated to determine the capacitance spectra, and through which its −ΔB = −w(C − Cgeo) ~ f could be plotted. According to the relationship of τdc = k × τp, where k was determined to be 0.56, the transfer time and further the carrier mobility could be obtained. The carrier mobility depended on the electric field according to Poole-Frenkel model was further investigated in this report.
In order to identify the density and material type, high energy protons, electrons, and heavy ions are used to radiograph dense objects. The particles pass through the object, undergo multiple coulomb scattering, and are focused onto an image plane by a magnetic lens system. A modified beam line at the Institute of Modern Physics of the Chinese Academy of Sciences has been developed for heavy-ion radiography. It can radiograph a static object with a spatial resolution of about 65 µm (1 σ). This paper presents the heavy-ion radiography facility at the Institute of Modern Physics, including the beam optics, the simulation of radiography by Monte Carlo code and the experimental result with 600 MeV/u carbon ions. In addition, dedicated beam lines for proton radiography which are planned are also introduced.
We have fabricated Ag-decorated ZnO nanoplate arrays by combining water-bath heating toward ZnO hexagonal nanoplate arrays and subsequent decoration of Ag films or nanoparticles on the ZnO surfaces by magnetron sputtering or photoreduction. Experimental surface-enhanced Raman scattering (SERS) results show that Ag-film–ZnO hybrid substrates with different Ag sputtering times exhibit a large difference in enhanced SERS signals for Rhodamine 6G (10−7 M). Atomic force microscope analysis reveals that two kinds of positions create abundant “hot spots” in this SERS substrate: one is located at the gap between adjacent separate Ag-film–ZnO hybrid nanoplates, and the other is located at the V-grooves formed by two adjacent interlaced Ag-film–ZnO hybrid nanoplates. The effects of simultaneous changes in interplate spacing and groove wall angle are considered to be the key factors affecting the SERS of our prepared Ag-film–ZnO hybrid substrates, which have also been evaluated by finite-difference time-domain simulation.
Background: Although knowledge of established risk factors for Alzheimer's disease (AD) can logically contribute to the search for predictors of the progression of cognitive impairment, it has not yet been firmly established where in the cognitive impairment process these risk factors exert their effects and how to predict quantitatively for the progression of mild cognitive impairments (MCI) to AD. This study aimed to determine whether known risk factors increased the risk of progression from MCI to AD and to make prediction based on transition probabilities.
Methods: Based on ten examinations of 600 community-dwelling MCI residents and cognitive assessments to classify individuals into MCI, global impairment, and AD, a multi-state Markov Cox's regression model was used and the hazard ratios with their confidence intervals and transition probabilities were estimated.
Results: Multivariate analysis showed that gender, age, and hypertension were statistically significant predictors of transition from MCI to global impairment; age, education, and reading statistically influenced transition from global impairment to MCI; gender, age, hypertension, diabetes, and apolipoprotein E geneε4 status were statistically associated with transition from global impairment to AD. Subjects at MCI were more likely (67%) to remain in that cognitive state at the next cognitive assessment than to transition to cognitive deterioration. For global impairment, probability of remaining in the same state was only 18% and that of forward transition was three times more likely than that of backward transition.
Conclusions: Known risk factors influenced differently for different transitions. Transition from global impairment was more likely to worsen to severe cognitive deterioration than transition from MCI.
In this work, the metallic element Ru is introduced into a-Si:H. The structural and electrical properties of the films doped with Ru have been investigated. Raman spectra reveal that the addition of Ru disarranges further the intrinsically disordered amorphous network and generates more coordinated defects. Meanwhile, a new paramagnetic signal, associated with the holes localized in valence band tail, has been observed. Moreover, the conductivity increases by about nine orders of magnitude with the increase of doping concentration, and the temperature coefficient of resistance (TCR) results show that this material may have a potential application in the infrared detectors.
Rui Lu, Center for Plant Cell Biology, Department of Plant Pathology, University of California, Riverside, CA 92521, USA,
Hongwei Li, Center for Plant Cell Biology, Department of Plant Pathology, University of California, Riverside, CA 92521, USA,
Wan-Xiang Li, Center for Plant Cell Biology, Department of Plant Pathology, University of California, Riverside, CA 92521, USA,
Shou-Wei Ding, Center for Plant Cell Biology, Department of Plant Pathology, University of California, Riverside, CA 92521, USA
Drosophila has been an excellent model for the mechanistic studies of innate immunity (Hoffmann, 2003). Recently, a new RNA-based antiviral immunity with features of both innate and adaptive immunities has been described in Drosophila and Anopheles cells (Li et al., 2002, 2004). This RNA-silencing-mediated immunity is characterized by the production of pathogen-derived, 22-nt small RNAs that serve as specificity determinants inside a multi-subunit complex. Similar to innate immunity, however, the new invertebrate antiviral response is capable of a rapid virus clearance in the absence of a virus-encoded suppressor of RNA silencing. The discovery of a new antiviral pathway in insects opens up the possibility of using this pathway to prevent transmission of vector-borne virus pathogens such as dengue and West Nile viruses.
THE RNA-SILENCING PATHWAY
Homology-dependent gene silencing was discovered in transgenic plants in a form of co-suppression between introduced transgenes or between a transgene and its homologous endogenous gene (Matzke et al., 1989; Napoli et al., 1990; Van der Krol et al., 1990). Similar gene-silencing phenomena have subsequently been described in a wide range of eukaryotic organisms such as fungi, worms, flies and mammals (Denli & Hannon, 2003; Fire et al., 1998). A generic term, RNA silencing (Ding, 2000), has been used to describe these related RNA-guided gene regulatory mechanisms variously termed post-transcriptional gene silencing (PTGS) in plants, quelling in fungi and RNA interference (RNAi) in animals.
A core feature of RNA silencing detected in all organisms is the production of 21–26-nt small RNAs from structured or double-stranded RNA (dsRNA) by the endoribonuclease Dicer (Bernstein et al., 2001; Hamilton et al., 2002; Hamilton & Baulcombe, 1999; Hammond et al., 2000; Zamore et al., 2000).
Maturation of porcine oocytes was examined after oocytes were cooled at the germinal vesicle stage. Cumulus-oocyte complexes (COCs) collected from medium-sized follicles were cooled at 24 °C or 4 °C for 5, 30 or 120 min in a solution with or without 1.5 M dimethylsulfoxide (DMSO). After rewarming, COCs were cultured in maturation medium at 39 °C, 5% CO2 in air for 44 h. Meiotic spindle organisation (by immunostaining and confocal microscopy), nuclear maturation (by orcein staining) and cytoplasmic maturation (by intracellular glutathione assay) of oocytes were examined after maturation. When COCs were cooled at 24 °C for various times in the medium without DMSO, a tendency to decreased spindle formation, nuclear maturation and cytoplasmic maturation was observed, but there was no statistical difference compared with controls. Addition of DMSO during cooling inhibited subsequent nuclear maturation and spindle formation. When COCs were cooled at 4 °C, both nuclear and cytoplasmic maturation as well as spindle formation were inhibited in most oocytes in a time-dependent manner. DMSO during cooling did not have any beneficial effect on subsequent oocyte maturation and spindle formation. These results suggest that porcine oocytes are very sensitive to a drop in the temperature before exposure to culture. Cooling oocytes before maturation inhibits their subsequent spindle organisation, nuclear and cytoplasmic maturation. Addition of DMSO to the cooling solution did not protect porcine oocytes from cooling-induced damage.