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To determine whether the Chinese heart-healthy diet (Sichuan cuisine version) (CHH diet-SC) was more expensive than the conventional Sichuan diet and explore the food groups and nutrients that mainly affected the cost of CHH diet-SC.
Design:
Cost analysis of 4-week intervention diets in the Sichuan center representing southwestern China in the CHH diet study.
Setting:
A multicentre, parallel-group, single-blind, randomised feeding trial evaluating the efficacy of lowering blood pressure with the cuisine-based CHH diet.
Participants:
Totally, fifty-three participants with hypertension aged 25–75 years in the Sichuan center were randomised into the control group (n 26) or the CHH diet-SC group (n 27).
Results:
The CHH diet-SC was more expensive than the control diet (¥27·87 ± 2·41 v. ¥25·18 ± 2·79 equals $3·90 ± 0·34 v. $3·52 ± 0·39, P < 0·001), and the incremental cost-effectiveness ratio for a 1-mm Hg systolic blood pressure reduction was ¥9·12 ($1·28). Intakes and the cost of seafood, dairy products, fruits, soybeans and nuts, whole grains and mixed beans were higher for the CHH diet-SC than for the control diet (P < 0·001). Intakes of vitamin B1, vitamin B6, vitamin C, Mg and phosphorus were positively correlated with the cost (P < 0·05).
Conclusions:
The CHH diet-SC costs more than the conventional Sichuan diet, partly due to the high cost of specific food groups. Positive correlations between the intakes of vitamin B1, vitamin B6, vitamin C, Mg, phosphorus and the dietary cost could be a direction to adjust the composition within the food groups to reduce the cost of the CHH diet-SC.
Adsorption desulfurization is a potential new method for deep desulfurization of fuel oil. The development of adsorbents with high adsorption capacity and selectivity is the core of deep adsorption desulfurization. The adsorption behavior of thiophene in MCM-41 mesoporous materials modified by various metal ions was studied in order to understand the adsorption desulfurization process of molecular sieves. The Fe-, Co-, and Zn-modified MCM-41 materials were prepared using a one-step in situ hydrothermal synthesis method. The modified MCM-41 molecular sieves maintained the mesoporous structure, and the metal ions had specific dispersion on the surface of the molecular sieves. Adsorption of thiophene on the surfaces of molecular sieves had both physical and chemical characteristics. The adsorption desulfurization performance of the modified molecular sieve was superior to that of the pure silica molecular sieve. In the simulated gasoline with sulfur content of 220 μg/g, when the amount of adsorbent used was 100 mg, the adsorptive desulfurization performance tended to be in equilibrium, and the optimum adsorption temperature was 30°C. Fe-MCM-41 and MCM-41 molecular sieves reached adsorption equilibrium after ~60 min, but the desulfurization rate of Co-MCM-41 and Zn-MCM-41 still increased slightly. The kinetic simulation results indicated that the pseudo-second-order kinetics adsorption model described well the adsorption process of thiophene on molecular sieves. The molecular sieve Fe-MCM-41 had the best desulfurization performance with an equilibrium adsorption capacity of 14.02 mg/g and the desulfurization rate was ~90%.
The clay mineral content of the Oligocene sediments in the Linxia Basin has been investigated using X-ray diffraction, scanning electron microscopy, and high-resolution transmission electron microscopy. The clay mineral assemblages are mainly mixed-layer illite-smectite (I-S), illite, kaolinite and minor palygorskite in the early-Middle Oligocene deposits, mixed-layer I-S, illite and kaolinite in the Middle Oligocene deposits, mainly illite and chlorite (usually >50–70 vol.%), mixed-layer I-S, and trace to minor palygorskite in the late Oligocene sediments, respectively. The mineral assemblage indicates a warm and seasonally humid climate in the Middle Oligocene, with an episode of warm and dry conditions in the early stage of the Middle Oligocene, and a trend of temperature decrease and more arid conditions in the late Oligocene. Climate evolution in the Oligocene corresponds with the significant elevation change in central Tibet since late Oligocene, and therefore, suggests that tectonic-forced cooling of climate took place in Linxia in the northeast margin of the Tibetan Plateau. The ubiquitous mixed-layer I-S and carbonates throughout the Oligocene sediments reflect relatively small fluctuations in climate conditions during the epoch. The changes in clay mineral components and feldspars in the late Oligocene suggest a variation in the source of clastic materials, which probably reflects an increase in erosion of soils and poorly weathered parent rock in more elevated or high-relief source areas during this period of tectonic uplift.
This study aims to evaluate the predictive role of age-adjusted Charlson comorbidity index (ACCI) scores for in-hospital prognosis of severe fever in thrombocytopenia syndrome (SFTS) patients. A total of 192 patients diagnosed with SFTS were selected as the study subjects. Clinical data were retrospectively collected. Receiver operating characteristic curves were used to evaluate the diagnostic value of ACCI for the mortality of SFTS patients, and Cox regression models were used to assess the association between predictive factors and prognosis. The 192 SFTS patients were divided into two groups according to the clinical endpoints (survivors/non-survivors). The results showed that the mortality of the 192 hospitalized SFTS patients was 26.6%. The ACCI score of the survivor group was significantly lower than that of the non-survivor group. Multivariate Cox regression analysis showed that the increased ACCI score was a significant predictor of poor prognosis in SFTS. Kaplan–Meier survival analysis showed that SFTS patients with an ACCI >2.5 had shorter mean survival times, indicating a poor prognosis. Our findings suggest that ACCI, as an easy-to-use clinical indicator, may offer a simple and feasible approach for clinicians to determine the severity of SFTS.
We document and explain the sharp performance deterioration of smart beta indexes after the corresponding exchange-traded funds (ETFs) are launched for investment. While smart beta is purported to deliver excess returns through factor exposures, the market-adjusted return of smart beta indexes drops from about 3% “on paper” before ETF listings to about −0.50% to −1% after ETF listings. This performance decline cannot be explained by variation in factor premia, strategic timing, or diminishing returns to scale. Instead, we find strong evidence of data mining in the construction of smart beta indexes, which helps ETFs attract flows, as investors respond positively to backtests.
Many protected areas worldwide have been established to protect the last natural refuges of flagship animal species. However, long-established protected areas do not always match the current distributions of target species under changing environmental conditions. Here we present a case study of the Asian elephant Elephas maximus in Xishuangbanna, south-west China, to evaluate whether the established protected areas match the species’ current distribution and to identify key habitat patches for Asian elephant conservation. Our results show that currently only 24.5% of the predicted Asian elephant distribution in Xishuangbanna is located within Xishuangbanna National Nature Reserve, which was established for elephant conservation. Based on the predicted Asian elephant distribution, we identified the most important habitat patches for elephant conservation in Xishuangbanna. The three most important patches were outside Xishuangbanna National Nature Reserve and together they contained 43.3% of the estimated food resources for Asian elephants in all patches in Xishuangbanna. Thus, we identified a spatial mismatch between immobile protected areas and mobile animals. We recommend the inclusion of the three identified key habitat patches in a new national park currently being planned by the Chinese authorities for the conservation of the Asian elephant.
We presented the first photometric and orbital period investigations for four W Ursae Majoris-type binaries: V473 And, V805 And, LQ Com, and EG CVn. The photometric solutions suggested that V805 And and LQ Com are two total-eclipse contact binaries, while V473 And and EG CVn are partial-eclipse ones. V473 And and LQ Com belong to the A-subtype contact binaries, while V805 And and EG CVn belong to the W subtype. The O’Connell effects found in the light curves of V805 And, LQ Com, and EG CVn can be interpreted as a result of a cool spot on the surface of their less massive and hotter primary components. Based on two different methods, the absolute physical parameters were properly determined. Combining the eclipse timings derived from our observations and survey’s data with those collected from literature, we investigated their orbital period variations. The results show that the orbital periods of V473 And, V805 And, and EG CVn are undergoing a secular decrease/increase superposed a periodic variation, while LQ Com exhibits a possible cyclic period variation with a small amplitude. The secular period changes are caused mainly by the mass transfer between two components, while the cyclic period oscillations may be interpreted as the results of either the light-time effect due to the third body or the cyclic magnetic activity. Finally, we made a statistical investigation for nearly 200 contact binaries with reliable physical parameters. The statistical results suggested that the W-subtype systems are more evolved than the A-subtype ones. Furthermore, the evolutionary direction of A-subtype into W-subtype systems is also discussed. The opposite evolutionary direction seems to be unlikely because it requires an increase of the total mass, the orbital angular momentum, and the temperature differences between two components of a binary system.
The longitudinal associations between academic competence-building and depression symptoms were investigated among 741 early adolescents in Singapore. Extending from past studies on academic achievement and depression, the current research tested two competing hypotheses – the academic incompetence hypothesis versus the adjustment erosion hypothesis using a 3-wave longitudinal study over an academic year. The former hypothesis suggests that prior deficits in academic competence-building lead to subsequent depression symptoms, whereas the latter posits that previous depression leads to subsequent deficits in competence-building. Longitudinal associations between a higher-order competence-building factor (operationalized using multiple constituent motivational variables) and depression were examined using a random intercept cross-lagged panel model. Results indicated that within-individual decreases in competence-building prospectively predicted subsequent within-individual increases in depression symptoms, but the opposite effect was not observed. Within-individual fluctuations in competence-building also predicted end-of-year grades and teacher-reported adjustment problems. Overall, the current findings were consistent with the academic incompetence hypothesis, suggesting that interventions aimed at sustaining academic competence-building could offer protection against the worsening of depression. These results clarified the within-individual developmental dynamics between academic competence-building and depression symptoms in adolescents over time.
Sporadic clusters of healthcare-associated coronavirus disease 2019 (COVID-19) occurred despite intense rostered routine surveillance and a highly vaccinated healthcare worker (HCW) population, during a community surge of the severe acute respiratory coronavirus virus 2 (SARS-CoV-2) B.1.617.2 δ (delta) variant. Genomic analysis facilitated timely cluster detection and uncovered additional linkages via HCWs moving between clinical areas and among HCWs sharing a common lunch area, enabling early intervention.
To investigate the intrinsic mechanism for mixing enhancement by variable-density (VD) behaviour, a canonical VD mixing extracted from a supersonic streamwise vortex protocol, a shock–bubble interaction (SBI), is numerically studied and compared with a counterpart of passive-scalar (PS) mixing. It is meaningful to observe that the maximum concentration decays much faster in a VD SBI than in a PS SBI regardless of the shock Mach number ($Ma=1.22 - 4$). The quasi-Lamb–Oseen-type velocity distribution in the PS SBI is found by analysing the azimuthal velocity that stretches the bubble. Meanwhile, for the VD SBI, an additional stretching enhanced by the secondary baroclinic vorticity (SBV) production contributes to the faster-mixing decay. The underlying mechanism of the SBV-enhanced stretching is further revealed through the density and velocity difference between the light shocked bubble and the heavy ambient air. By combining the SBV-accelerated stretching model and the initial shock compression, a novel mixing time estimation for VD SBI is theoretically proposed by solving the advection–diffusion equation under a deformation field of an axisymmetric vortex with the additional SBV-induced azimuthal velocity. Based on the mixing time model, a mixing enhancement number, defined by the ratio of VD and PS mixing time further, reveals the contribution from the VD effect, which implies a better control of the density distribution for mixing enhancement in a supersonic streamwise vortex.
This study investigates the mechanism by which maternal protein restriction induces hepatic autophagy-related gene expression in the offspring of rats. Pregnant Sprague-Dawley rats were fed either a control diet (C, 18 % energy from protein) or a low-protein diet (LP, 8·5 % energy from protein) during gestation, followed by the control diet during lactation and post-weaning. Liver tissue was collected from the offspring at postnatal day 38 and divided into four groups according to sex and maternal diet (F-C, F-LP, M-C and M-LP) for further analysis. Autophagy-related mRNA and protein levels were determined by real-time PCR and Western blotting, respectively. In addition, chromatin immunoprecipitation (ChIP) was performed to investigate the interactions between transcription factors and autophagy-related genes. Protein levels of p- eukaryotic translation initiation factor 2a and activating transcription factor 4 (ATF4) were increased only in the female offspring born to dams fed the LP diet. Correlatively, the mRNA expression of hepatic autophagy-related genes including Map1lc3b, P62/Sqstm1, Becn1, Atg3, Atg7 and Atg10 was significantly greater in the F-LP group than in the F-C group. Furthermore, ChIP results showed greater ATF4 and C/EBP homology protein (CHOP) binding at the regions of a set of autophagy-related genes in the F-LP group than in the F-C group. Our data demonstrated that a maternal LP diet transcriptionally programmed hepatic autophagy-related gene expression only in female rat offspring. This transcriptional programme involved the activation of the eIF2α/ATF4 pathway and intricate regulation by transcription factors ATF4 and CHOP.
The provenance and tectonic setting of the Lower–Middle Triassic clastic sediments from the Napo basin, South China, have been examined here using detrital modes, whole-rock geochemistry and detrital zircon U–Pb ages. Field investigations indicate that these sediments consist of fan delta, slope and turbidity fan facies with dominantly southward palaeocurrent directions. Detrital modes and geochemical characteristics of the clastic rocks indicate that they were derived from mixed magmatic arc and Palaeozoic successions in a continental island arc setting, with no significant sediment recycling. The U–Pb age spectra of sandstone detrital zircons from different stratigraphic positions are similar, with one major group (300–230 Ma), two subordinate groups (400–320 Ma and 480–420 Ma, respectively) and two scattered groups (1200–800 Ma and 2000–1700 Ma, respectively). Thus, we consider that the north late Permian – Middle Triassic volcanic rocks and the uplifted Palaeozoic sedimentary/volcanic sequences constituted the predominant sources. The detritus derived from the late Permian Emeishan mafic rocks is subordinate and limited. The pre-Devonian zircons are likely sedimentary-recycled or magmatic-captured instead of directly derived from the early Palaeozoic orogen (e.g. Yunkai massif) and Neoproterozoic Jiangnan orogen because of the topographic barrier of a magmatic arc and carbonate platform. Considering the spatial and temporal distribution characteristics of the volcanic arc and ophiolite, we suggest that the Triassic Napo basin was a fore-arc basin within a continental island arc setting, which developed in response to the northward subduction of the Babu–Cao Bang branch ocean beneath the South China Block.
Global warming and more intense heat wave periods impact health. Heat illness during heat waves has not been studied in the prehospital setting of a low- and middle-income country (LMIC). Early intervention in the community and in the prehospital setting can improve outcomes. Hence, this paper aims to describe the characteristics of heat illness patients utilizing the ambulance service in Telangana state, India with the aim of optimizing public prevention and first aid strategies and prehospital response to this growing problem.
Methods:
This retrospective observational study reviewed patients presenting to Telangana’s prehospital emergency care system with heat illness symptoms during the heat wave period from March through June in 2018 and 2019. Descriptive analysis was done on the prehospital, dispatch, and environmental data looking at the patients’ characteristics and prehospital intervention.
Results:
There were 295 cases in 2018 and 230 cases in 2019 from March-June. The overall incidence of calls with heat illness symptoms was 1.5 cases per 100,000 people. The Scheduled Tribes (ST) had the highest incidence of 4.5 per 100,000 people. Over 96% were from the white income group (below poverty line) while two percent were from the pink income group (above poverty line). From geospatial mapping of the cases, the highest incidence of calls came from the rural, tribal areas. However, the time to response in rural areas was longer than that in an urban area. Males with an average age of 47 were more likely to be affected. The three most common symptoms recorded by the first responders were vomiting (44.4%), general weakness (28.7%), and diarrhea (15.9%). The three most common medical interventions on scene were oxygen therapy (35.1%), oral rehydration salt (ORS) solution administration (26.9%), and intravenous fluid administration (27.0%), with cold sponging infrequently mentioned.
Conclusion:
This descriptive study provides a snapshot of the regions and groups of people most affected by heat illness during heat waves and the heterogeneous symptom presentation and challenges with management in the prehospital setting. These data may aid planning of prehospital resources and preparation of community first responders during heat wave periods.
Trailing vortices typically persist into the extreme far-wake where the asymptotic perturbation dominates. In this work, we investigate the mechanism underlying the asymptotic growth of perturbation in trailing vortices by looking into the linear instabilities of two canonical trailing vortex systems, namely an isolated vortex and a co-rotating vortex pair with axial flow, generated by an M6 swept wing without/with winglets in a wind tunnel experiment. The dynamics and wandering phenomena of both vortex configurations are characterized by stereoscopic particle image velocimetry (SPIV). Their linear perturbation modes are acquired by local and bi-global linear stability analyses. For the isolated trailing vortex, the dominating perturbation mode is found to be a viscous, unstable Mode-A counter to the vortex rotation ($m>0$), while Mode-A with $m\leqslant 0$ is essentially damped and Mode-P, which is exclusive to $|m|\leqslant 1$, remains marginally stable. For the co-rotating vortex pair, the upper vortex is subject to an unstable, azimuthal perturbation, while the dominating perturbation of the lower vortex is radial. The perturbation mode of the upper vortex is more unstable than that of the lower vortex. The difference is supported by the corresponding wandering amplitude. The dominating modes of the two vortex configurations manifest an identical feature of azimuthal perturbations penetrating the core boundary. The dominating mode overwhelms those centre modes confined within the core. For both vortex configurations, a limiting penetration depth exists, where the perturbation is most amplified asymptotically. The limiting penetration depth is ascribed to the alignment of the critical point with vortex shear. For the isolated vortex, it is the shear layer at the core boundary; for the vortex pair, it is the mutual shear layer of both vortices. The asymptotic growth of perturbations is thus attributed to an interaction between the respective characteristic layers of the perturbation and the flow at the leading order.
To establish optimal gestational weight gain (GWG) in Chinese pregnant women by Chinese-specific BMI categories and compare the new recommendations with the Institute of Medicine (IOM) 2009 guidelines.
Design:
Multicentre, prospective cohort study. Unconditional logistic regression analysis was used to evaluate the OR, 95 % CI and the predicted probabilities of adverse pregnancy outcomes. The optimal GWG range was defined as the range that did not exceed a 1 % increase from the lowest predicted probability in each pre-pregnancy BMI group.
Setting:
From nine cities in mainland China.
Participants:
A total of 3731 women with singleton pregnancy were recruited from April 2013 to December 2014.
Results:
The optimal GWG (ranges) by Chinese-specific BMI was 15·0 (12·8–17·1), 14·2 (12·1–16·4) and 12·6 (10·4–14·9) kg for underweight, normal weight and overweight pregnant women, respectively. Inappropriate GWG was associated with several adverse pregnancy outcomes. Compared with women gaining weight within our proposed recommendations, women with excessive GWG had higher risk for macrosomia, large for gestational age and caesarean section, whereas those with inadequate GWG had higher risk for low birth weight, small for gestational age and preterm delivery. The comparison between our proposed recommendations and IOM 2009 guidelines showed that our recommendations were comparable with the IOM 2009 guidelines and could well predict the risk of several adverse pregnancy outcomes.
Conclusions:
Inappropriate GWG was associated with higher risk of several adverse pregnancy outcomes. Optimal GWG recommendations proposed in the present study could be applied to Chinese pregnant women.
Anaemia is a global public health problem affecting women worldwide, and reproductive-age women are at increased risk. We conducted a population-based cross-sectional study analysing the prevalence of overall anaemia and anaemia according to severity in Chinese pre-pregnant women to update current knowledge on anaemia epidemiology. Based on the National Free Preconception Check-up Projects supported by the Chinese government, 5 679 782 women participating in this project in 2017 were included in the present study. The cyanmethemoglobin method was applied to assess Hb concentrations. Univariate and multivariate logistic regressions were applied for associated factors. The prevalence of anaemia among Chinese pre-pregnant women was 21·64 % (mild: 14·10 %, moderate: 7·17 % and severe : 0·37 %). The prevalence of overall and severe anaemia was the highest in Tibet and the lowest in Beijing among thirty-one provinces. Women’s age, region, ethnic origin, educational level, occupation and pregnancy history were all correlated with anaemia. Women with B blood type (adjusted OR (aOR) = 0·89), higher BMI (overweight: aOR = 0·84; obesity: aOR = 0·70) and alcohol consumption (aOR = 0·69) were less likely to have anaemia, while those with rhesus negative blood type (aOR = 1·10), history of anaemia (aOR = 2·60), older age at menarche (aOR = 1·19), heavy menstrual blood loss (aOR = 1·39), longer menstrual period (aOR = 1·09) and shorter menstrual cycle (aOR = 1·08) were more likely to suffer from anaemia. Meat or egg eaters were not significantly associated with severe anaemia. Anaemia is of moderate public health significance among Chinese pre-pregnant women. Interventions should be considered to prevent anaemia to the greatest extent possible to avoid potential harm in this population.
This experiment was designed to investigate the effect of supplementing conjugated linoleic acid (CLA) in breeder hens diet on development and hepatic lipid metabolism of chick offspring. Hy-Line Brown breeder hens were allocated into two groups, supplemented with 0 (control (CT)) or 0·5 % CLA for 8 weeks. Offspring chicks were grouped according to the mother generation and fed for 7 d. CLA treatment had no significant influence on development, egg quality and fertility of breeder hens but darkened the egg yolks in shade and increased yolk sac mass compared with the CT group. Addition of CLA resulted in increased body mass and liver mass and decreased deposition of subcutaneous adipose tissue in chick offspring. The serum TAG and total cholesterol levels of chick offspring were decreased in CLA group. CLA treatment increased the incorporation of both CLA isomers (c9t11 and t10c12) in the liver of chick offspring, accompanied by the decreased hepatic TAG levels, related to the significant reduction of fatty acid synthase (FAS) and acetyl-CoA carboxylase (ACC) enzyme activities and the increased carnitine palmitoyltransferase-1 (CPT1) enzyme activity. Meanwhile, CLA treatment reduced the mRNA expression of genes related to fatty acid biosynthesis (FAS, ACC and sterol regulatory element-binding protein-1c) and induced the expression of genes related to β-oxidative (CPT1, AMP-activated protein kinase and PPARα) in chick offspring liver. In summary, the addition of CLA in breeder hens diet significantly increased the incorporation of CLA in the liver of chick offspring, which further regulate hepatic lipid metabolism.
Although poverty associated with severe mental illness (SMI) has been documented in many studies, little long-term evidence of social drift exists. This study aimed to unravel the poverty transitions among persons with SMI in a fast change community in China.
Methods
Two mental health surveys, using the International Classification of Disease (ICD-10), were conducted in the same six townships of Xinjin county, Chengdu, China in 1994 and 2015. A total of 308 persons with SMI identified in 1994 were followed up in 2015. The profiles of poverty transitions were identified and regression modelling methods were applied to determine the predictive factors of poverty transitions.
Results
The poverty rate of persons with SMI increased from 39.9% to 49.4% in 1994 and 2015. A larger proportion of them had fallen into poverty (27.3%) rather than moved out of it (17.8%). Those persons with SMI who had lost work ability, had physical illness and more severe mental disabilities in 1994, as well as those who had experienced negative changes on these factors were more likely to live in persistent poverty or fall into poverty. Higher education level and medical treatment were major protective factors of falling into poverty.
Conclusions
This study shows long-term evidence on the social drift of persons with SMI during the period of rapid social development in China. Further targeted poverty alleviation interventions should be crucial for improving treatment and mental recovery and alleviating poverty related to SMI.
This study aimed to evaluate to what extent the different interval times between trophectoderm (TE) biopsy and vitrification influence the clinical outcomes in preimplantation genetic testing (PGT) cycles. Patients who underwent frozen embryo transfer (FET) after PGT between 2015 and 2019 were recruited. In total, 297 cycles with single day 5 euploid blastocyst transfer were included. These cycles were divided into three groups according to the interval times: <1 h group, 1–2 h group, and ≥2 h group. Blastocyst survival, clinical pregnancy, miscarriage, and ongoing pregnancy rates were compared. The results showed that, in PGT-SR cycles, survival rate in the ≥2 h group (96.72%) was significantly lower than in the <1 h group (100%, P = 0.047). The clinical pregnancy rate in the ≥2 h group was 55.93%, significantly lower than in the <1 h group (74.26%, P = 0.017). The ongoing pregnancy rates in the 1–2 h group and the ≥2 h group were 48.28% and 47.46%, respectively, significantly lower than that in the <1 h group (67.33%, P < 0.05). The miscarriage rate in the 1–2 h group was 18.42%, significantly higher than that in the <1 h group (5.33%, P = 0.027). In PGT-A cycles, the clinical pregnancy and ongoing pregnancy rates in the <1 h group were 67.44% and 53.49%, respectively, higher than that in the 1–2 h group (52.94%, 47.06%, P > 0.05) and the ≥2 h group (52.63%, 36.84%, P > 0.05). In conclusion, vitrification of blastocysts beyond 1 h after biopsy significantly influences embryo survival and clinical outcomes and is therefore not recommended.