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The first case of 2019-nCoV pneumonia infection occurred in Wuhan, Hubei Province, South China Seafood Market in December 2019. As a group with a high probability of infection, health workers are faced with a certain degree of psychological challenges in the process of facing the epidemic. This study attempts to evaluate the impact of 2019-nCoV outbreak on the psychological state of Chinese health workers and to explore the influencing factors. During the period from 31 January 2020 to 4 February 2020, the ‘Questionnaire Star’ electronic questionnaire system was used to collect data. The 2019-nCoV impact questionnaire and The Impact of Event Scale (IES) were used to check the psychological status of health workers in China. A total of 442 valid data were collected in this study. Seventy-four (16.7%) male and 368 (83.3%) female individuals participated in this study. The average score of high arousal dimension was 5.15 (s.d. = 4.71), and the median score was 4.0 (IQR 2.0, 7.0). The average score of IES was 15.26 (s.d. = 11.23), and the median score was 13.5 (IQR 7.0, 21.0). Multiple regression analysis showed that there were critical statistical differences in high arousal scores among different gender groups (male 3.0 vs. female 5.0, P = 0.075). Whether being quarantined had significant statistical differences of IES scores (being quarantined 16.0 vs. not being quarantined 13.0, P = 0.021). The overall impact of the 2019-nCoV outbreak on health workers is at a mild level. Chinese health workers have good psychological coping ability in the face of public health emergencies.
Varicella is an acute respiratory infectious diseases, with high transmissibility and quick dissemination. In this study, an SEIR (susceptible-exposed-infected-recovered) dynamic model was established to explore the optimal prevention and control measures according to the epidemiological characteristics about varicella outbreak in a school in a central city of China. Berkeley Madonna 8.3.18 and Microsoft Office Excel 2010 software were employed for the model simulation and data management, respectively. The result showed that the simulated result of SEIR model agreed well with the reported data when β (infected rate) equal to 0.067. Models showed that the cumulative number of cases was only 13 when isolation adopted when the infected individuals were identified (assuming isolation rate was up to 100%); the cumulative number of cases was only two and the TAR (total attack rate) was 0.56% when the vaccination coefficient reached 50%. The cumulative number of cases did not change significantly with the change of efficiency of ventilation and disinfection, but the peak time was delayed; when δ (vaccination coefficient) = 0.1, m (ventilation efficiency) = 0.7 or δ = 0.2, m = 0.5 or δ = 0.3, m = 0.1 or δ = 0.4 and above, the cumulative number of cases would reduce to one case and TAR would reduce to 0.28% with combined interventions. Varicella outbreak in school could be controlled through strict isolation or vaccination singly; combined interventions have been adopted when the vaccination coefficient was low.
Women experience both physical and psychological changes during different phases of the menstrual cycle (MC), which can affect their decision making. The present study aims to investigate the impact of the MC on women’s preferences for conspicuous consumption. In three studies, women in the low-fertility phase were found to be more inclined toward conspicuous consumption, with the MC effect on conspicuous consumption being mediated by the extent of pride. We assumed that women in the low-fertility phase would feel less proud due to an evolutionary drive and that they would consume conspicuous products as a means of compensation. Meanwhile, women who were only children did not manifest such behavior. We infer that women from one-child families may have a greater sense of security and confidence, which buffers the mediating effect. This research contributes to both evolutionary psychology and marketing research and provides new insights for future studies.
Let χ(t) = a0tn – a1tn−1 + ⋯ + (−1)rartn−r be the chromatic polynomial of a graph, the characteristic polynomial of a matroid, or the characteristic polynomial of an arrangement of hyperplanes. For any integer k = 0, 1, …, r and real number x ⩾ k − r − 1, we obtain a linear bound of the coefficient sequence, that is
where m is the size of the graph, matroid, or hyperplane arrangement. It extends Whitney’s sign-alternating theorem, Meredith’s upper bound theorem, and Dowling and Wilson’s lower bound theorem on the coefficient sequence. In the end, we also propose a problem on the combinatorial interpretation of the above inequality.
Suicide attempt (SA), which is one of the strongest predictors of completed suicide, is common in major depressive disorder (MDD) but its prevalence across epidemiological studies has been mixed. The aim of this comprehensive meta-analysis was to examine the pooled prevalence of SA in individuals with MDD.
A systematic literature search was conducted in PubMed, Embase, PsycINFO, Web of Science and Cochrane Library from their commencement date until 27 December 2017. Original studies containing data on prevalence of SA in individuals with MDD were analyzed.
In all, 65 studies with a total of 27 340 individuals with MDD were included. Using the random effects model, the pooled lifetime prevalence of SA was 31% [95% confidence interval (CI) 27–34%], 1-year prevalence was 8% (95% CI 3–14%) and 1-month prevalence was 24% (95% CI 15–34%). Subgroup analyses revealed that the lifetime prevalence of SA was significantly associated with the patient setting, study region and income level, while the 1-month prevalence of SA was associated with only the patient setting.
This meta-analysis confirmed that SA was common in individuals with MDD across the world. Careful screening and appropriate interventions should be implemented for SA in the MDD population.
This study analyzed and assessed publication trends in articles on “disaster medicine,” using scientometric analysis. Data were obtained from the Web of Science Core Collection (WoSCC) of Thomson Reuters on March 27, 2017. A total of 564 publications on disaster medicine were identified. There was a mild increase in the number of articles on disaster medicine from 2008 (n=55) to 2016 (n=83). Disaster Medicine and Public Health Preparedness published the most articles, the majority of articles were published in the United States, and the leading institute was Tohoku University. F. Della Corte, M. D. Christian, and P. L. Ingrassia were the top authors on the topic, and the field of public health generated the most publications. Terms analysis indicated that emergency medicine, public health, disaster preparedness, natural disasters, medicine, and management were the research hotspots, whereas Hurricane Katrina, mechanical ventilation, occupational medicine, intensive care, and European journals represented the frontiers of disaster medicine research. Overall, our analysis revealed that disaster medicine studies are closely related to other medical fields and provides researchers and policy-makers in this area with new insight into the hotspots and dynamic directions. (Disaster Med Public Health Preparedness. 2019;13:165–172)
Early life is considered a critical period for determining long-term metabolic health. Postnatal over-nutrition may alter glucocorticoid (GC) metabolism and increase the risk of developing obesity and metabolic disorders in adulthood. Our aim was to assess the effects of the dose and timing of a fish oil diet on obesity and the expression of GC-activated enzyme 11β-hydroxysteroid dehydrogenase type 1 (HSD1) in postnatal overfed rats. Litter sizes were adjusted to three (small litter (SL)) or ten (normal litter) rats on postnatal day 3 to induce overfeeding or normal feeding. The SL rats were divided into three groups after weaning: high-dose fish oil (HFO), low-dose fish oil (LFO) and standard-diet groups. After 10 weeks, the HFO diet reduced body weight gain (16 %, P<0·05), improved glucose intolerance and decreased hyperlipaemia levels (P<0·05) in SL rats, but the LFO diet did not have any effect on the same rats. Moreover, we chose postnatal week 3 (W3), 6 (W6) and 8 (W8) as the intervention time points at which to begin the 10-week HFO diet, and found that the HFO diet improved glucose utilisation and lipid metabolism at all time points. However, body weight of SL rats was reversed to normal levels by the post-weaning intervention (461 (sem 9·1) v. 450 (sem 2·0)). 11β-HSD1 mRNA expression in the adipose tissue (49 (sem 7·5) v. 161 (sem 18·3), P<0·05) and hepatic tissue (11 (sem 0·9) v. 16 (sem 1·5), P<0·05) was decreased by the HFO diet at W3, but not at W6 or W8 (P>0·05). In conclusion, the post-weaning HFO diet could reverse adverse outcomes and decrease tissue GC activity in postnatal overfed rats.
Hepatitis C virus (HCV) has become a global public health problem. Many studies have been conducted to identify risk factors for HCV infection. However, some of these studies reported inconsistent results. Using data collected from 11 methadone clinics, we fit both a non-spatial logistical regression and a geographically weighted logistic regression to analyse the association between HCV infection and some factors at the individual level. This study enrolled 5401 patients with 30·0% HCV infection prevalence. The non-spatial logistical regression found that injection history, drug rehabilitation history and senior high-school education or above were related to HCV infection; and being married was negatively associated with HCV infection. Using the spatial model, we found that Yi ethnicity was negatively related to HCV infection in 62·0% of townships, and being married was negatively associated with HCV infection in 81·0% of townships. Senior high-school education or above was positively associated with HCV infection in 55·2% of townships of the Yi Autonomous Prefecture. The spatial model offers better understanding of the geographical variations of the risk factors associated with HCV infection. The geographical variations may be useful for customizing intervention strategies for local regions for more efficient allocation of limited resources to control transmission of HCV.
The prevalence and factors associated with delays in help seeking for people with dementia in China are unknown.
Within 1,010 consecutively registered participants in the Clinical Pathway for Alzheimer's Disease in China (CPAD) study (NCT01779310), 576 persons with dementia (PWDs) and their informants reported the estimated time from symptom onset to first medical visit seeking diagnosis. Univariate analysis of general linear model was used to examine the potential factors associated with the delayed diagnosis seeking.
The median duration from the first noticeable symptom to the first visit seeking diagnosis or treatment was 1.77 years. Individuals with a positive family history of dementia had longer duration (p = 0.05). Compared with other types of dementia, people with vascular dementia (VaD) were referred for diagnosis earliest, and the sequence for such delays was: VaD < Alzheimer's disease (AD) < frontotemporal dementia (FTD) (p < 0.001). Subtypes of dementia (p < 0.001), family history (p = 0.01), and education level (p = 0.03) were associated with the increased delay in help seeking.
In China, seeking diagnosis for PWDs is delayed for approximately 2 years, even in well-established memory clinics. Clinical features, family history, and less education may impede help seeking in dementia care.
Paleomonsoon strength is difficult to reconstruct. The strength of the East Asian monsoon and precipitation over large areas correlate well on a decadal time scale. Thus, monsoon strength can be reconstructed through proxies of sediments originating from large areas. In the present study, we investigated the characteristics of a sediment core from the Northern Yellow Sea Mud. The results showed that sedimentary characteristics are mainly controlled by discharge changes of the Yellow River. The relationships between median grain size (MZ), magnetic susceptibility (MS) and the SiO2/Al2O3 ratio of sediments and spatially averaged precipitation around the Yellow River Drainage basin reveal that changes in MZ and MS are correlated with variation in precipitation. The agreement of temporal trends in MZ, MS and the monsoon strength index confirm that spatially averaged precipitation changes in the Yellow River Drainage basin on decadal time scale are driven by the monsoon strength. These characteristics of marine sediments from the Northern Yellow Sea Mud can thus be used as proxies for monsoon strength.
Complex cerebral aneurysms may require indirect treatment with revascularization. This manuscript describes various surgical revascularization techniques together with clinical outcomes.
Thirty-two consecutive patients with complex cerebral aneurysm were managed from November 2005 to October 2008. Techniques used for revascularization were high-flow bypass, low-flow bypass, branch artery reimplantion, and primary reanastomosis. Physiologic and anatomic monitoring technologies, including electroencephalography, somatosensory evoked potential monitoring, microvascular doppler ultrasonography, and/or indocyanine green videoangiography were used intraoperatively to assess both brain physiology and vascular anatomy. Patient outcome was determined using the Glasgow Outcome Scale at discharge and at a mean of 12 months post operation (range 6-25 months).
Two cervical carotid aneurysms (6%) were resected followed by primary reanastomosis, 21 aneurysms (66%) were trapped following saphenous vein high-flow bypasses, five (16%) were clipped after superficial temporal or occipital artery low-flow bypasses, and four (12%) middle cerebral branch arteries were reimplanted. Of the 32 patients at discharge, 29 (91%) had a Glasgow Outcome Scale of four or five, two (6%) had severe disability, and one (3%) died.
Cerebral revascularization remains an effective and reliable procedure for treatment of complex cerebral aneurysms. Low morbidity and mortality rates reflect the maturity of patient selection and surgical technique in the management of these lesions.
Measuring Na in silicate glasses can be difficult in transmission electron microscopy due to modifications induced by electron irradiation. The modifications involve not only the loss of Na from the illuminated region, but also the formation of Na and Na2O. This work compares the electron energy loss spectroscopy (EELS) of plasmon and Na L23 edge in Na2O–SiO2 glass with those in Na and Na2O. The interpretations of the fine structures in Na L23 edge were also given with the aid of full multiplescattering calculations. It demonstrates that the formation of metallic Na can be easily identified by its bulk plasmon at about 5.8 eV, and the formation of Na2O can be better seen by Na L23-edge fine structure.
Broadband near-infrared (IR) luminescence in transparent alkali gallium silicate glass-ceramics containing Ni2+-doped β-Ga2O3 nanocrystals was observed. This broadband emission could be attributed to the 3T2g (3F) → 3A2g (3F) transition of octahedral Ni2+ ions in glass-ceramics. The full width at half-maximum (FWHM) of the near-IR luminescence and fluorescent lifetime of the glass-ceramic doped with 0.10 mol% NiO were 260 nm and ∼1220 μs, respectively. It is expected that transparent Ni2+-doped β-Ga2O3 glass-ceramics with this broad near-IR emission and long fluorescent lifetime have potential applications as super-broadband optical amplification media.
We introduce a new perspective on the conceptualization and measurement of ownership identities of China's listed companies. Previous work analyzing the strategy and performance implications of the ownership structure in Chinese firms has used the official categorization provided by state bodies in China. In this categorization, state shareholding, legal person shareholding and A-shares dominate. This official categorization, however, obscures the ultimate identity of a shareholder; this can confound conceptual and empirical work on die strategy and performance implications of ownership identity. We refine the existing classification by recategorizing shareholders into 16 types, which can then be regrouped into relevant categories of shareholders, such as government or private, to enable analysis of ownership identity and ownership concentration issues in China's listed companies. Our new classification can help provide consistency in the burgeoning research on the strategy and performance implications of the concentration and identity aspects of ownership structure in China's listed companies.
This paper reports the recent results of a transmission electron microscopy study of cold-welded and e-beam deposited Au-Ag interfaces. Dust particles were observed to be embedded between the cold-welded interfaces. These are shown to amplify the defect regions caused by surface asperities. Electron energy loss spectroscopy (EELS) analysis revealed that there was no significant diffusion zone across the cold welding interface. However, sub-micron mechanical twining structures were revealed by transmission electron microscopy (TEM) analyses. These were found to penetrate through both the cold-welded and control Au-Ag interfaces, but with different orientations.
In a study of the Double Jeopardy (DJ) phenomenon and the mediating
effect of brand penetration between advertising and brand loyalty, we
integrate a survey of 19,335 consumers on their buying behavior of 187
brands across two fast moving consumer goods categories, shampoo and
detergent, and a database of advertising expenditures on these brands in
four major cities in China. We find that (1) smaller brands are punished
twice for being small, following the well-known DJ pattern, which says
that brands with larger market penetration tend to enjoy higher repeated
purchases and smaller brands attract fewer buyers who also buy less; (2)
brand penetration plays a mediating role in the relationship between
advertising and brand loyalty; and (3) there is an asymmetric effect of
market penetration on brand loyalty for small and big brands.
In order to better understand the influence of RNA transcript
context on RNA localization and catalytic RNA efficacy
in vivo, we have constructed and characterized several
expression cassettes useful for transcribing short RNAs
with well defined 5′ and 3′ appended flanking
sequences. These cassettes contain promoter sequences from
the human U1 snRNA, U6 snRNA, or tRNAMeti genes,
fused to various processing/stabilizing sequences.
The levels of expression and the sub-cellular localization
of the resulting RNAs were determined and compared with
those obtained from Pol II promoters normally linked to
mRNA production, which include a cap and polyadenylation
signal. The tRNA, U1, and U6 transcripts were nuclear in
localization and expressed at the highest levels, while
the standard Pol II promoted transcripts were cytoplasmic
and present at lower levels.
The ability of these cassettes to confer ribozyme activity
in vivo was tested with two assays. First, an SIV-growth
hormone reporter gene was transiently transfected into
human embryonic kidney cells expressing an anti-SIV ribozyme.
Second, cultured T lymphocytes expressing an anti-HIV ribozyme
were challenged with HIV. In both cases, we found that
the ribozymes were effective only when expressed as capped,
polyadenylated RNAs transcribed from Pol II cassettes that
generate a cytoplasmically localized ribozyme that facilitates
co-localization with its target. We also show that the
inability of the other cassettes to support ribozyme-mediated
inhibitory activity against their cytoplasmic target is
very likely due to the resulting nuclear localization of
these ribozymes. These studies demonstrate that the ribozyme
expression cassette determines its intracellular localization
and, hence, its corresponding functional activity.
We use a three-component model of a spiral galaxy, given by (Huang et al., 1979):
1.An outer halo with a gravitational potential of the form
where R2 = x2 + y2 + z2, M1 = 1.2 × 1011M⊙ and b1 = 1.1 Kpc.
2.A nucleus, with a gravitational potential given by
where M0 = 1.1 × 107M⊙, and b0 = 0.61 × 10−2 Kpc.
3.A self-gravitating disk containing N stars. The density distribution in the z-direction is assumed to be:
where α = 2.1 Kpc−1 is the equivalent semi-thickness of the galaxy, and σ(r) is the surface density. We consider three different initial expressions for σ(r):
i.A Toomre (1963) disk.
ii.A uniform distribution.
iii.An exponential distribution.
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