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This chapter reviews the geochemical and geophysical constraints on the carbon budget in the metallic core of Earth, discusses whether carbon is a dominant light element in the core, and assesses whether the core hosts the largest reservoir of carbon on Earth.
Polyhedral YVO4: Ln3+ (Ln = Eu, Sm, Yb/Er, Yb/Tm) microcrystals were fabricated via a facile sol–gel auto-combustion method using NH4VO3 as vanadium source in the presence of glycine. The X-ray diffraction patterns were well matched with pure YVO4, and the doped lanthanide ions did not change the host structure. The YVO4 microcrystals annealed from 500 to 1000 °C for 3 h were polyhedral and ranged in particle size from 0.1 to 2 μm. The luminescence properties of YVO4: Ln3+ (Ln = Eu, Sm, Yb/Er, Yb/Tm) samples indicated that all of the YVO4: Ln3+ samples exhibited typical emission spectra of Ln3+ cations, suggesting that the Ln3+ cations were well doped in YVO4 and could be excited efficiently through matrix absorption. In addition, the corresponding mechanisms of emission and energy transfer in the YVO4: Ln3+ are proposed.
To report an outbreak of measles with epidemiological link between Hong Kong International Airport (HKIA) and a hospital.
Epidemiological investigations, patients’ measles serology, and phylogenetic analysis of the hemagglutinin (H) and nucleoprotein (N) genes of measles virus isolates were conducted.
In total, 29 HKIA staff of diverse ranks and working locations were infected with measles within 1 month. Significantly fewer affected staff had history of travel than non–HKIA-related measles patients [10 of 29 (34.5%) vs 28 of 35 (80%); P < .01]. Of 9 airport staff who could recall detailed exposure history, 6 (66.7%) had visited self-service food premises at HKIA during the incubation period, where food trays, as observed during the epidemiological field investigation, were not washed after use. Furthermore, 1 airport baggage handler who was admitted to hospital A before rash onset infected 2 healthcare workers (HCWs) known to have 2 doses of MMR vaccination with positive measles IgG and lower viral loads in respiratory specimens. Infections in these 2 HCWs warranted contact tracing of another 168 persons (97 patients and 71 HCWs). Phylogenetic comparison of H and N gene sequences confirmed the clonality of outbreak strains.
Despite good herd immunity with overall seroprevalence of >95% against measles, major outbreaks of measles occurred among HKIA staff having daily contact with many international pssengers. Lessons from severe acute respiratory syndrome (SARS) and measles outbreaks suggested that an airport can be a strategic epidemic center. Pre-exanthem transmission of measles from airport staff to HCWs with secondary vaccine failure poses a grave challenge to hospital infection control.
Light-absorbing impurities (LAIs, e.g. black carbon (BC), organic carbon (OC), mineral dust (MD)) deposited on snow cover reduce albedo and accelerate its melting. Northern Xinjiang (NX) is an arid and semi-arid inland region, where snowmelt leads to frequent floods that have been a serious threat to local ecological security. There is still a lack of quantitative assessments of the effects of LAIs on snowmelt in the region. This study investigates spatial variations of LAIs in snow and its effect on snow albedo, radiative forcing (RF) and snowmelt across NX. Results showed that concentrations of BC, OC (only water-insoluble OC), MD ranged from 32 to 8841 ng g−1, 77 to 8568 ng g−1 and 0.46 to 236 µg g−1, respectively. Weather Research and Forecasting Chemistry model suggested that residential emission was the largest source of BC. Snow, Ice, and Aerosol Radiative modelling showed that the average contribution of BC and MD to snow albedo reduction was 17 and 3%, respectively. RF caused by BC significantly exceeded RF caused by MD. In different scenarios, changes in snow cover duration (SCD) caused by BC and MD decreased by 1.36 ± 0.61 to 6.12 ± 3.38 d. Compared with MD, BC was the main dominant factor in reducing snow albedo and SCD across NX.
We investigated the microscopic mineral characteristics of modern eolian dust particulates and the trace-element compositions of the siliciclastic fractions of these samples, collected from the Philippine Sea in 2014 and 2015, and conducted an air mass backwards trajectory analysis of dust particulates in the spring and winter of 2015, to better constrain the provenances and transport dynamics of dust delivered to this region. The microscopic minerals show obvious signatures of dust deposition and physical abrasion, indicating long-distance wind transport from the Asian deserts. The trace-element compositions (Zr–Th–Sc) display a binary mixture of eolian materials derived from the eastern Asian deserts and the central Asian deserts, which is similar to the result of the Sr–Nd isotopic compositions of modern sediment trap sediments collected on the Benham Rise in 2015. We demonstrate that modern dust sediments in the Philippine Sea primarily originate from the Ordos Desert (generally > 80%), while the contributions of the Taklimakan Desert and the Badain Jaran Desert are small. Eolian dust particulates raised from source regions are predominantly transported to the Philippine Sea by the East Asian winter monsoon, but not by the westerlies. In addition, our results indicate that increased precipitation in the source regions can result in relatively low dust fluxes in the Philippine Sea, and there is a period of 6–7 days for eolian dust originating from source areas to be delivered to the Philippine Sea.
Previous studies have shown that the Dietary Approaches to Stop Hypertension (DASH) diet might contribute to managing risk factors of non-alcoholic fatty liver disease (NAFLD), but evidence is limited. We examined the association of DASH diet score (DASH-DS) with NAFLD, as well as the intermediary effects of serum retinol-binding protein-4 (RBP4), serum high-sensitivity C-reactive protein (hs-CRP), serum TAG, homeostasis model assessment of insulin resistance (HOMA-IR) and BMI.
We performed a cross-sectional analysis of a population-based cohort study. Dietary data and lifestyle factors were assessed by face-to-face interviews and the DASH-DS was then calculated. We assessed serum RBP4, hs-CRP and TAG and calculated HOMA-IR. The presence and degree of NAFLD were determined by abdominal sonography.
Guangzhou Nutrition and Health Study participants, aged 40–75 years at baseline (n 3051).
After adjusting for potential covariates, we found an inverse association between DASH-DS and the presence of NAFLD (Ptrend = 0·009). The OR (95 % CI) of NAFLD for quintiles 2–5 were 0·78 (0·62, 0·98), 0·74 (0·59, 0·94), 0·69 (0·55, 0·86) and 0·77 (0·61, 0·97), respectively. Path analyses indicated that a higher DASH-DS was associated with lower serum RBP4, hs-CRP, TAG, HOMA-IR and BMI, which were positively associated with the degree of NAFLD.
Adherence to the DASH diet was independently associated with a marked lower prevalence of NAFLD in Chinese adults, especially in women and those without abdominal obesity, and might be mediated by reducing RBP4, hs-CRP, TAG, HOMA-IR and BMI.
Androgenetic embryonic stem (AgES) cells offer a possible tool for patient-specific pluripotent stem cells that will benefit genomic imprinting studies and clinic applications. However, the difficulty in producing androgenetic embryos and the unbalanced expression of imprinted genes make the therapeutic applicability of AgES cells uncertain. In this study, we produced androgenetic embryos by injecting two sperm into an enucleated metaphase II (MII) oocyte. By this method, 88.48% of oocytes survived after injection, and 20.24% of these developed to the blastocyst stage. We successfully generated AgES cell lines from the androgenetic embryos and assayed the expression of imprinted genes in the cell lines. We found that the morphological characteristics of AgES cells were similar to that of fertilized embryonic stem cells (fES), such as expression of key pluripotent markers, and generation of cell derivatives representing all three germ layers following in vivo and in vitro differentiation. Furthermore, activation of paternal imprinted genes was detected, H19, ASC12 and Tss3 in AgES cell activation levels were lower while other examined genes showed no significant difference to that of fES cells. Interestingly, among examined maternal imprinted genes, only Mest and Igf2 were significantly increased, while levels of other detected genes were no different to that of fES cells. These results demonstrated that activation of some paternal imprinted genes, as well as recovery of maternal imprinted genes, was present in AgES cells. We differentiated AgES cells into a beating embryoid body in vitro, and discovered that the AgES cells did not show significant higher efficiency in myocardial differentiation potential.
In this work, two types of zinc adipate β-nucleating agents, Adi-Zn(OH)2 (1:1) and Adi-ZnO (1:1), for polypropylene (PP) were prepared and their performances were evaluated and compared with commercial β-nucleating agent (named CNA). Results showed that Adi-Zn(OH)2 (1:1) was more effective in promoting PP to form β-crystals and improving the impact strength of PP in the range of nucleating agent addition (0–0.4 wt%). Based on these findings, the ratio of adipic acid to zinc hydroxide and the nonisothermal crystallization kinetics of the optimum ratio of adipic acid to zinc hydroxide were systematically studied; results showed that at 0.2 wt%, Adi-Zn(OH)2 (1:2), the nucleated PP displayed the highest impact strength, which was 2.6 times that of pure PP and 42% higher than that of CNA. Besides, Adi-Zn(OH)2 (1:2) could also afford to induce the formation of a high content of β-crystals and shorten the crystallization half time (t1/2) and accelerate the crystallization of PP.
A novel tetragonal B2CO structure (tP16-B2CO), formed by strong covalent sp2–sp3 B–C and B–O bonds, was predicted with aid of an unbiased structure searching method. With the energy lower than those of previously proposed candidates, except oI16-B2CO, tP16-B2CO was identified as the thermodynamic metastable phase for B2CO compound. The elastic matrix and phonon dispersion spectra declare that tP16-B2CO is mechanically and dynamically stable. The electronic band structure calculation at ambient pressure and a series of high pressure has manifested the indirect semiconducting and band gap increases first and then decreases with pressure increases. The calculation of mechanical properties such as hardness and stress–strain relations of tP16 structure revealed its common hard nature with high hardness of 23.19 GPa and anisotropy with the max stress along  is far higher than that along .
Above-threshold ionization (ATI) is one of the most fundamental processess when atoms or molecules are subjected to intense laser fields. Analysis of ATI process in intense laser fields by a Wigner-distribution-like (WDL) function is reviewed in this paper. The WDL function is used to obtain various time-related distributions, such as time-energy distribution, ionization time distribution, and time-emission angle distribution and so on, of atoms in laser field pulses with different laser parameters. For the linearly polarized laser pulses, the time-energy distribution intuitively shows from a quantum point of view the relationship between the ionization moment and the final energy and clearly reveals the origin of interference structures in the photoelectron spectrum. In particular, for linearly polarized few-cycle laser pulses, all calculated distributions show the dependence of electron behavior on the ionization time, emission direction, and carrier-envelope phase (CEP). For elliptically polarized few-cycle pulses, we calculate the angular distribution, ionization time distribution, and time-emission distribution, which are compared with the semiclassical calculations. Analysis shows that the offset angle (difference between positions of the peaks in the angular distributions obtained by two methods) in the angular distributions does not correspond to the offset time (difference between positions of the peaks in the ionization time distributions obtained by two methods) in the ionization time distributions, which implies that the attosecond angular streaking technique based on this correspondence between the offset angle and time is in principle inaccurate. Furthermore, the offset time cannot be interpreted as tunneling time.
Flaxseed oil is rich in ɑ-linolenic acid (ALA), which is the metabolic precursor of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). This study investigated the effect of flaxseed oil supplementation on lipopolysaccharide (LPS)-induced muscle atrophy and carbohydrate oxidation impairment in a piglet model. Twenty-four weaned pigs were used in a 2 × 2 factorial experiment including dietary treatment (5% corn oil vs. 5% flaxseed oil) and LPS challenge (saline vs. LPS). On day 21 of treatment, the pigs were injected intraperitoneally with 100 μg/kg BW LPS, or sterile saline. At 4 h after injection, blood, gastrocnemius muscle and longissimus dorsi (LD) muscle were collected. Flaxseed oil supplementation increased ALA, EPA, total n-3 polyunsaturated fatty acids contents, protein/DNA ratio, and pyruvate dehydrogenase complex (PDC) quantity in muscles (p<0.05). In addition, flaxseed oil reduced mRNA expression of toll-like receptor (TLR) 4 and nucleotide-binding oligomerization domain protein (NOD) 2 and their downstream signaling molecules in muscles, and decreased plasma concentrations of tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-8, and mRNA expression of TNF-α, IL-1β and IL-6 (p<0.05). Moreover, flaxseed oil inclusion increased the ratios of phosphorylated Akt 1/ total Akt 1 and phosphorylated forkhead Box O (FOXO) 1/ total FOXO1, and reduced mRNA expression of FOXO1, muscle RING finger (MuRF) 1, and pyruvate dehydrogenase kinase (PDK) 4 in muscles (p<0.05). These results suggest that flaxseed oil might have a positive effect on alleviating muscle protein loss and carbohydrates oxidation impairment induced by LPS challenge through regulation of TLR4/NOD and Akt/FOXO signaling pathway.
Hot extrusion experiments were conducted on Al–5.50Zn–2.35Mg–1.36Cu (wt%) alloy under various temperatures and extrusion speeds. Results indicated that dynamic recovery occurred at low temperature and then dynamic recrystallization was triggered at higher temperature or speed. High billet temperature reduced the grain size and increased the volume fraction of Al23CuFe4 and AlMgZn. When the extrusion speed was enhanced to 0.5 mm/s, the peak of MgZn2 phase diminished in the results of X-ray diffraction. The strong brass and S components appeared in all the extruded specimens. Texture intensity gradually decreased with increasing temperature and the fraction of texture components was also significantly affected by the extrusion parameters. The extruded alloy exhibited the highest ultimate tensile strength of 350.2 MPa at 480 °C and 0.5 mm/s and the best elongation of 16.78% at 520 °C and 0.1 mm/s. Moreover, the extrusion speed had more significant effects on the tensile properties than that of the temperature.
It has been suggested that dust generation was closely linked to the development of global ice sheets and/or cooling. This feature has allowed Asian dust to be a potential chronostratigraphic tool in North Pacific Ocean (NPO) sediments. The orbital-scale age control in NPO sediments is usually established by adjusting the benthic-foraminiferal δ18O to the global δ18O stack (LR04). However, it would become difficult if the sediments did not contain enough foraminifera. This study investigates Sr and Nd isotopes, trace elements, mineralogy and grain size of the ‘operationally defined aeolian dust’ (ODED) extracted from the sediments recovered at Ocean Drilling Program (ODP) site 1209B on the Shatsky Rise in the NPO covering the past five glacial–interglacial cycles. The geochemical results show that the ODED at site 1209B is actually a mixture of Asian dust and volcanic ash. The variation of Nd isotope mimics the cycles of glacial–interglacial ice sheets as revealed by the global benthic foraminifera’s oxygen isotope stack (LR04) over the past 500 ka. The low (high) ϵNd values corresponded with the cool (warm) periods. We propose that ϵNd variation reflects the evolving aeolian dust in site 1209 sediments. The excellent agreement between ϵNd values at site 1209B and LR04 stack over the past 500 ka allows establishing the orbital-timescale age control by tuning ϵNd to the LR04 curve. We thus propose that Nd isotope provides a chronostratigraphic technique in NPO sediments, especially for sediments with a limited amount of foraminifera.
The Beijing Twin Study (BeTwiSt), which was established in 2006, is an ongoing study aiming to investigate the genetic and environmental etiology of adolescent psychopathology. Resting-state brain imaging datasets have been examined for same-sex twins, and other psychological traits and emotional and behavioral variables have been examined for all twins. Based on the registry, the main findings regarding the etiological mechanism underlying adolescent development, magnetic resonance imaging results, and genetic and environmental influences on other psychological traits have been published. This article summarizes the key findings in these three areas and discusses future plans for the BeTwiSt.
Few of the previous studies of clinical high risk of psychosis (CHR) have explored whether outcomes other than conversion, such as poor functioning or treatment responses, are better predicted when using risk calculators. To answer this question, we compared the predictive accuracy between the outcome of conversion and poor functioning by using the NAPLS-2 risk calculator.
Three hundred CHR individuals were identified using the Chinese version of the Structured Interview for Prodromal Symptoms. Of these, 228 (76.0%) completed neurocognitive assessments at baseline and 199 (66.3%) had at least a 1-year follow-up assessment. The latter group was used in the NAPLS-2 risk calculator.
We divided the sample into two broad categories based on different outcome definitions, conversion (n = 46) v. non-conversion (n = 153) or recovery (n = 138) v. poor functioning (n = 61). Interestingly, the NAPLS-2 risk calculator showed moderate discrimination of subsequent conversion to psychosis in this sample with an area under the receiver operating characteristic curve (AUC) of 0.631 (p = 0.007). However, for discriminating poor functioning, the AUC of the model increased to 0.754 (p < 0.001).
Our results suggest that the current risk calculator was a better fit for predicting a poor functional outcome and treatment response than it was in the prediction of conversion to psychosis.
Using ethanol adsorption calorimetry, the surface energetics of two carbon substrates and two products in microwave-assisted carbon nanotube (CNT) growth was studied. In this study, the ethanol adsorption enthalpies of the two graphene-based samples at 25 °C were measured successfully. Specifically, the near-zero differential enthalpies of ethanol adsorption are −75.7 kJ/mol for graphene and −63.4 kJ/mol for CNT-grafted graphene. Subsequently, the differential enthalpy curve of each sample becomes less exothermic until reaching a plateau, −55.8 kJ/mol for graphene and −49.7 kJ/mol for CNT-grafted graphene, suggesting favorable adsorbate–adsorbent binding. Moreover, the authors interpreted and discussed the partial molar entropy and chemical potential of adsorption as the ethanol surface coverage (loading) increases. Due to the low surface areas of carbon black–based samples, adsorption calorimetry could not be performed. This model study demonstrates that using adsorption calorimetry as a fundamental tool and ethanol as the molecular probe, the overall surface energetics of high–surface area carbon materials can be estimated.
To provide scientific, theoretical support for the improvement of medical disaster training, we systematically analyzed the National Disaster Life Support (NDLS) Course and established a training curriculum with feedback based on the current status of disaster medicine in China.
The gray prediction model is applied to long-term forecast research on course effect. In line with the hypothesis, the NDLS course with feedback capability is more scientific and standardized.
The current training NDLS course system is suitable for Chinese medical disasters. After accepting the course training, audiences’ capabilities were enhanced. In the constructed GM (1,1) model prediction, the developing coefficients of the pretest and the posttest are 0.04 and 0.057, respectively. In light of the coefficient, the model is appropriate for the long-term prediction. The predicted results can be used as the basis for constructing training closed-loop optimization feedback. It can indicate that the course system has a good effect as well.
According to the constructed GM model, the NDLS course system is scientific, practical, and operational. The research results can provide reference for relevant departments and be used for the construction of similar training course systems.
l-Carnitine is essential for mitochondrial β-oxidation and has been used as a lipid-lowering feed additive in humans and farmed animals. d-Carnitine is an optical isomer of l-carnitine and dl-carnitine has been widely used in animal feeds. However, the functional differences between l- and d-carnitine are difficult to study because of the endogenous l-carnitine background. In the present study, we developed a low-carnitine Nile tilapia model by treating fish with a carnitine synthesis inhibitor, and used this model to investigate the functional differences between l- and d-carnitine in nutrient metabolism in fish. l- or d-carnitine (0·4 g/kg diet) was fed to the low-carnitine tilapia for 6 weeks. l-Carnitine feeding increased the acyl-carnitine concentration from 3522 to 10 822 ng/g and alleviated the lipid deposition from 15·89 to 11·97 % in the liver of low-carnitine tilapia. However, as compared with l-carnitine group, d-carnitine feeding reduced the acyl-carnitine concentration from 10 822 to 5482 ng/g, and increased lipid deposition from 11·97 to 20·21 % and the mRNA expression of the genes involved in β-oxidation and detoxification in the liver. d-Carnitine feeding also induced hepatic inflammation, oxidative stress and apoptosis. A metabolomic investigation further showed that d-carnitine feeding increased glycolysis, protein metabolism and activity of the tricarboxylic acid cycle and oxidative phosphorylation. Thus, l-carnitine can be physiologically utilised in fish, whereas d-carnitine is metabolised as a xenobiotic and induces lipotoxicity. d-Carnitine-fed fish demonstrates increases in peroxisomal β-oxidation, glycolysis and amino acid degradation to maintain energy homeostasis. Therefore, d-carnitine is not recommended for use in farmed animals.
To explore whether and how group cognitive-behavioural therapy (GCBT) plus medication differs from medication alone for the treatment of generalised anxiety disorder (GAD).
Hundred and seventy patients were randomly assigned to the GCBT plus duloxetine (n=89) or duloxetine group (n=81). The primary outcomes were Hamilton Anxiety Scale (HAMA) response and remission rates. The explorative secondary measures included score reductions from baseline in the HAMA total, psychic, and somatic anxiety subscales (HAMA-PA, HAMA-SA), the Hamilton Depression Scale, the Severity Subscale of Clinical Global Impression Scale, Global Assessment of Functioning, and the 12-item Short-Form Health Survey. Assessments were conducted at baseline, 4-week, 8-week, and 3-month follow-up.
At 4 weeks, HAMA response (GCBT group 57.0% vs. control group 24.4%, p=0.000, Cohen’s d=0.90) and remission rates (GCBT group 21.5% vs. control group 6.2%, p=0.004; d=0.51), and most secondary outcomes (all p<0.05, d=0.36−0.77) showed that the combined therapy was superior. At 8 weeks, all the primary and secondary significant differences found at 4 weeks were maintained with smaller effect sizes (p<0.05, d=0.32−0.48). At 3-month follow-up, the combined therapy was only significantly superior in the HAMA total (p<0.045, d=0.43) and HAMA-PA score reductions (p<0.001, d=0.77). Logistic regression showed superiority of the combined therapy for HAMA response rates [odds ratio (OR)=2.12, 95% confidence interval (CI) 1.02−4.42, p=0.04] and remission rates (OR=2.80, 95% CI 1.27−6.16, p=0.01).
Compared with duloxetine alone, GCBT plus duloxetine showed significant treatment response for GAD over a shorter period of time, particularly for psychic anxiety symptoms, which may suggest that GCBT was effective in changing cognitive style.
In recent years, the discovery of massive quasars at
has provided a striking challenge to our understanding of the origin and growth of supermassive black holes in the early Universe. Mounting observational and theoretical evidence indicates the viability of massive seeds, formed by the collapse of supermassive stars, as a progenitor model for such early, massive accreting black holes. Although considerable progress has been made in our theoretical understanding, many questions remain regarding how (and how often) such objects may form, how they live and die, and how next generation observatories may yield new insight into the origin of these primordial titans. This review focusses on our present understanding of this remarkable formation scenario, based on the discussions held at the Monash Prato Centre from November 20 to 24, 2017, during the workshop ‘Titans of the Early Universe: The Origin of the First Supermassive Black Holes’.