Experimental studies on flow visualization and velocity field of compression ramp with different incoming boundary layers

Experimental studies which focus on flow visualization and the velocity field of a supersonic laminar/turbulent flow over a compression ramp were carried out in a Mach 3.0 wind tunnel. Fine flow structures and velocity field structures were obtained via NPLS （nanoparticle-tracer planar laser scattering） and PIV （particle image velocimetry） techniques, time- averaged flow structures were researched, and spatiotemporal evolutions of transient flow structures were analyzed. The flow visualization results indicated that when the ramp angles were 25~, a typical separation occurred in the laminar flow, some typical flow structures such as shock induced by the boundary layer, separation shock, reversed flow and reattachment shock were visible clearly. While a certain extent separation occurred in turbulent flow, the separation region was much smaller. When the ramp angles were 28~, laminar flow separated further, and the separation region expanded evidently, flow structures in the separation region were complex. While a typical separation occurred in turbulent flow, reversed flow structures were significant, flow structures in the separation region were relatively simple. The experimental results of velocity field were corresponding to flow visualization, and the velocity field structures of both compression ramp flows agreed with the flow structures well. There were three layered structures in the U component velocity, and the V component velocity appeared like an oblique ＂v＂. Some differences between these two compression ramp flows can be observed in the velocity profiles of the shear layer and the shearing intensity.

Observations and Modeling of Incoming Longwave Radiation to Snow Beneath Forest Canopies in the West Tianshan Mountains, China

Forest canopy reduces shortwave radiation and increases the incoming longwave radiation to snowpacks beneath forest canopies. Furthermore, the effect of forest canopy may be changed by complex topography. In this paper, we measured and simulated the incoming longwave radiation to snow beneath forest at different canopy openness in the west Tianshan Mountains, China(43°16'N, 84°24'E) during spring 2013. A sensitivity study was conducted to explore the way that terrain influenced the incoming longwave radiation to snow beneath forest canopies. In the simulation model, measurement datasets, including air temperature, incoming shortwave radiation above canopy, and longwave radiation enhanced by adjacent terrain, were applied to calculate the incoming longwave radiation to snow beneath forest canopy. The simulation results were consistent with the measurements on hourly scale and daily scale. The effect of longwave radiation enhanced by terrain was important than that of shortwave radiation above forest canopy with different openness except the 20% canopy openness. The longwave radiation enhanced due to adjacent terrain increases with the slope increase and temperature rise. When air temperature(or slope) is relatively low, thelongwave radiation enhanced by adjacent terrain is not sensitive to slope(or air temperature), but the sensitivity increases with the decrease of snow cover area on sunny slope. The effect of longwave radiation is especially sensitive when the snow cover on sunny slope melts completely. The effect of incoming shortwave radiation reflected by adjacent terrain on incoming longwave radiation to snow beneath forest canopies is more slight than that of the enhanced longwave radiation.

A Preliminary Study on the Training Model of Incoming Labor Forces by Higher Vocational Colleges

Based on the characteristics and employment situation of incoming labors,we should attach great importance to their training.With rich teaching resources,the higher vocational colleges should give full play to their advantages,get involved in the training,and enhance their studies of training models.

Effect of Incoming Vortex on Secondary Flows in Turbine Cascades with Planar and Non-Axisymmetric Endwall

Non-Axisymmetric Endwall Profiling(NAEP) is commonly utilized in turbines to eliminate secondary flows.Nevertheless,most of the NAEP methods consider a single-blade row environment without incorporating the effect of the stage environment.This paper aims to investigate the influence mechanism of the incoming vortex on the endwall secondary flow structures of NAEP in a highly loaded turbine cascade.To model the incoming vortex in a stage environment,this study considers a half-delta wing as the vortex generator at the upstream of the turbine cascade.The NAEP is then carried out for a highly loaded turbine cascade with an in-house numerical optimization design platform subject to no incoming vortex.Numerical simulation is also carried out under the influence of the incoming vortex for the turbine cascades with both planar and non-axisymmetric endwall.This paper furthers investigated the pitchwise effect of the incoming vortex on the near endwall secondary flow.The results indicate that the NAEP effectively improves the endwall secondary flow of the turbine cascade,where the total pressure loss coefficient and the secondary kinetic energy(SKE) are reduced by 7.3%,and 45.7%,respectively.It is further seen that with the incoming vortex,the NAEP achieves a considerable control effect on the endwall secondary flow of the turbine cascade.With incoming vortex,the NAEP can still achieve considerable control effect on the endwall secondary flow of the turbine cascade;the averaged reductions of loss coefficient and SKE are 7.8% and 14.2%,respectively.Under some pitchwise locations,incoming vortex can suppress the convection of cross-passage flow toward the suction corner greatly and reduce the loss coefficient of the baseline cascade.The incoming vortex at 4/7 pitch impinged right at the blade leading edge,leading to the generation of low-momentum fluid,which increased the size and the strength of the horseshoe vortex.Under all the pitchwise locations,NAEP can suppress the secondary vortices,e.g.,the passage vortex and the counter vortex,considerably.

Off-farm employment,agriculture production activities,and household dietary diversity in environmentally and economically vulnerable areas of Asia

Access to off-farm employment has been expected to be a critical approach to ending hunger and all forms of malnutrition,two important targets of achieving Zero Hunger.This study aims to investigate the role of off-farm employment in improving dietary diversity through substitution effect and complementary effect with agricultural production activities and income effect.This study adopts Poisson/Tobit/Probit/OLS regressions and the instrument variable method based on the primary survey data collected among 1,282 households at 12 sites in environmentally and economically vulnerable areas of China,Nepal,Cambodia,Thailand,and Myanmar in 2019.The results show that off-farm employment is positively associated with household dietary diversity and the consumption of flesh meat,fish and other aquatic animals,fruits,and milk and dairy products,which are rich in protein and micronutrients.The results of mechanism analysis show that off-farm employment contributes to household dietary diversity by improving crop diversity,especially for poor households,boosting the probability of livestock raising for households with the middle one-third disposal income,and increasing household income.The positive association between off-farm employment and household dietary diversity is much higher for households with the bottom one-third disposal income,low illiteracy,and from upper-middle income countries.These findings imply that off-farm employment does play a vital role in achieving multiple benefits of poverty alleviation,malnutrition reduction,and agrobiodiversity conservation in environmentally and economically vulnerable areas.However,it may enlarge the gaps in dietary diversity between households with low human capital and from low and lower-middle income countries and those with high human capital and from middle-high countries.

Women’s empowerment and food consumption:Evidence from female-headed households in Tanzania

Despite the growing recognition of women’s increasing role in the household and corresponding empowerment programs in sub-Saharan Africa,intensive research on the relationship between women’s influence and household food consumption is minimal.Using the most recent(2017-2018)national household survey data from Tanzania,this study examined the influence of women’s empowerment on household food consumption.First,we compared the monthly consumption of eight food categories between female-headed households(FHHs)and male-headed households(MHHs)using both descriptive statistics and the propensity score matching(PSM)method.Furthermore,we adopted the two-stage Linear Expenditure System and Almost Ideal Demand System model(LES-AIDS)to estimate income and price elasticities for the two household types.The results show that FHHs consume bread and cereals,fish,oils and fats,vegetables,and confectionery(sugar,jam,honey,chocolate,etc.)more than MHHs.Moreover,FHHs have a significantly higher income elasticity of demand for all food groups than MHHs.They are also more price elastic than MHHs in meat,fish,oils,fats,sugar,jam,honey,chocolate,etc.

Exploring the influences of education,intelligence and income on mental disorders

Background Previous studies have shown that educational attainment(EA),intelligence and income are key factors associated with mental disorders.However,the direct effects of each factor on major mental disorders are unclear.Aims We aimed to evaluate the overall and independent causal effects of the three psychosocial factors on common mental disorders.Methods Using genome-wide association study summary datasets,we performed Mendelian randomisation(MR)and multivariable MR(MVMR)analyses to assess potential associations between the 3 factors(EA,N=766345;household income,N=392422;intelligence,N=146808)and 13 common mental disorders,with sample sizes ranging from 9907 to 807553.Inverse-variance weighting was employed as the main method in the MR analysis.Results Our MR analysis showed that(1)higher EA was a protective factor for eight mental disorders but contributed to anorexia nervosa,obsessive-compulsive disorder(OCD),bipolar disorder(BD)and autism spectrum disorder(ASD);(2)higher intelligence was a protective factor for five mental disorders but a risk factor for OCD and ASD;(3)higher household income protected against 10 mental disorders but confers risk for anorexia nervosa.Our MVMR analysis showed that(1)higher EA was a direct protective factor for attention-deficit/hyperactivity disorder(ADHD)and insomnia but a direct risk factor for schizophrenia,BD and ASD;(2)higher intelligence was a direct protective factor for schizophrenia but a direct risk factor for major depressive disorder(MDD)and ASD;(3)higher income was a direct protective factor for seven mental disorders,including schizophrenia,BD,MDD,ASD,post-traumatic stress disorder,ADHD and anxiety disorder.Conclusions Our study reveals that education,intelligence and income intertwine with each other.For each factor,its independent effects on mental disorders present a more complex picture than its overall effects.

Add-on Renewables Aim to Decrease Impact and Increase Benefits

In the South Boulder Canal near Denver,CO,USA,turbine blades that resemble the mixers used to stir cake batter in kitchens(Fig.1)spin in the rushing water[1].Each of the turbines,manufactured by Emrgy of Atlanta,GA,USA,generates up to 25 kW of electricity for the area’s grid[2].In an orchard in southern Italy,an arcade of solar panels stands above rows of citron trees,which are valuable for the essential oils in their fruits[3].The solar panels not only produce electricity for local homes,but also protect the trees from the sun,reducing their water use by 70%[3].These are two examples of a clean energy trend:integrating power-generation with other uses.In the approach called agrivoltaics,for example,farmers and ranchers grow crops or raise livestock around and beneath solar panels(Fig.2)[4].Experts hope that such add-on strategies can spare farmland,cut the environmental costs of clean energy development,supply extra income to landowners,and furnish other benefits[5,6].

Influence of Transportation Accessibility on Urban-rural Income Disparity and Its Spatial Heterogeneity

Transportation accessibility has been treated as an important means of reducing the urban-rural income disparity.However,only a few studies have examined the effects of different types of transportation accessibility on urban-rural income disparity and their spatial heterogeneity.Based on data from 285 prefecture-level(and above)Chinese cities in 2000,2005,2010,2015,and 2020,this study uses spatial econometric models to examine how highway accessibility and railway accessibility influence the urban-rural income disparity and to identify their spatial heterogeneity.The result reveals that highway accessibility and railway accessibility have‘coreperiphery’ring-like circle structures.The urban-rural income disparity exhibits strong spatial clustering effects.Both highway accessibility and railway accessibility are negatively associated with urban-rural income disparity,and the former having a greater effect size.Moreover,there is a substitution effect between highway accessibility and railway accessibility in the whole sample.Furthermore,these associations differ in geographic regions.In the central region,highway accessibility is more important in reducing the urban-rural income disparity,but its effect is weakened with the increase of railway accessibility.In the western region,railway accessibility has a larger effect on narrowing the urban-rural income disparity,and this effect is strengthened by the increase of highway accessibility.We conclude that improving transportation accessibility is conducive to reducing the urban-rural income disparity but its effect is spatial heterogenetic.Highways and railways should be developed in a coordinated manner to promote an integrated transport network system.

Promotion of sexual and reproductive health in Pakistan-The role of technology and online awareness

Digital health innovations such as online webinars,websites,blogs,and health apps have been associated with increased sexual and reproductive health(SRH)among the general population.Many studies have been conducted in developed countries in the West;however,little research has been conducted in low-income countries,especially in Pakistan.The socioeconomic instability and the government's lack of awareness and knowledge have resulted in no regulations being placed to incorporate telehealth in medicine.The healthcare departments must take into consideration the lifechanging impact of telehealth and the barriers that prevent it in becoming known,to reduce the incidence of unsafe abortions and sexual health practices that prove to be a stigma in society.

First case of fungal keratitis secondary to Yamadazyma mexicana

Dear Editor,Fungal keratitis is a serious and potentially sightthreatening infection that poses a global health concern,with higher incidence rates reported in low-income countries and regions with tropical climates[1-3].Risk factors for fungal keratitis include trauma with vegetative matter,contact lens wear,history of ocular surgery,chronic topical steroid use,low socioeconomic status and tropical climate[1-2].Fungi have the propensity to penetrate deep into the corneal stroma,making the infection difficult to treat with topical antifungal agents alone.Complications such as corneal perforation and endophthalmitis can arise in severe cases,making early identification of the causative fungal pathogen of utmost importance[4-5].Moreover,obtaining susceptibilities to the available antifungal agents can be sight and eye saving[5].

Consensus on rapid screening for prodromal Alzheimer's disease in China

Alzheimer's disease(AD)is a common cause of dementia,characterised by cerebral amyloid-βdeposition,pathological tau and neurodegeneration.The prodromal stage of AD(pAD)refers to patients with mild cognitive impairment(MCl)and evidence of AD's pathology.At this stage,disease-modifying interventions should be used to prevent the progression to dementia.Given the inherent heterogeneity of MCl,more specific biomarkers are needed to elucidate the underlying AD's pathology.Although the uses of cerebrospinal fluid and positron emission tomography are widely accepted methods for detecting AD's pathology,their clinical applications are limited by their high costs and invasiveness,particularly in low-income areas in China.Therefore,to improve the early detection of Alzheimer's disease(AD)pathology through cost-effective screening methods,a panel of 45neurologists,psychiatrists andgerontologistswas invited to establish a formal consensus on the screening of pAD in China.The supportive evidence and grades of recommendations are based on a systematic literature review andfocus group discussion.National meetings were held to allow participants to review,vote and provide their expert opinions to reach a consensus.A majority(two-thirds)decision was used for questions for which consensus could not be reached.Recommended screening methods are presented in this publication,including neuropsychological assessment,peripheral biomarkers and brain imaging.In addition,a general workflow for Screening pAD in China is established,which will help clinicians identify individuals at high risk and determine therapeutic targets.

Assessing the role of forest resources in improving rural livelihoods in West Bengal of India

Forest resources play a vital role in supporting the livelihoods of rural communities residing in forest-rich areas.In India,a forest-rich country,a significant proportion of non-timber forest products(NTFPs)is consumed locally,supporting numerous rural communities relying on forests for essential resources,such as firewood,timber,and NTFPs.This study focuses on two forest-dominant districts in West Bengal of India,namely,Jhargram District and Paschim Medinipur District.Furthermore,this study aims to enhance the understanding of forest-dependent communities by comparing the standard of living among different village classes.Thus,we categorized villages into three classes based on the distance from home to forests,including inner villages,fringe villages,and outer villages.Through focus group discussions and household surveys,we explored the sources of local economy,income sources of household,and reasons for economic diversification in different village classes.The study findings confirm that substantial variations existed in the income sources and the standard of living in these villages.Forest income varied dramatically among the three village classes,with inner villages having greater forest income than fringe villages and outer villages.Meanwhile,households in outer villages depended on forests and engaged in diverse economic activities for their livelihoods.Compared with inner and fringe villages,households in outer villages derived a significant portion of their income from livestock.This discrepancy can be attributed to challenges,such as inadequate transportation,communication,and underdeveloped market chains in inner villages.Moreover,these findings emphasize the need to develop sustainable forest management practices,create alternative income-generation opportunities,and improve infrastructure and market access in inner villages,as well as promote economic diversification in outer villages.Through targeted policy measures,these forest-rich regions can achieve improved livelihoods,enhanced standard of living,and increased resilience for their communities.

Socio-Economic and Health Indicators’ Relation to Self-Assessed Health: A Case Study of Phai Tha Pho, Phichit Province, Thailand

Background: Self-assessed health (SAH) is used as a common method of sociology research to understand the implications of self-reported health and the link to social factors like education, income, and occupation. The paper explores the impact of socio-economic and health indicators on self-assessed health in the middle-aged to the senior population in a rural community in Thailand. Methods: Primary data were collected after conducting a randomized sampling for 100 people using direct interviews in two locations within the sub-district of Phai Tha Pho, Thailand. The target demographic was the middle-age to elderly population. A logit model was applied to the collected samples. Results: The study highlights that higher education, income, and sleep are high predictors for positive SAH while high blood sugar level has significant adverse effects on SAH. Detection of metabolic syndrome further indicates degraded overall health perception over time. Conclusion: The study demonstrated the relationship between socio-economic indicators and illnesses alongside individual SAH in rural Thailand. Accordingly, policies have been proposed that include targeted subsidies for healthy food alternatives, promoting work-rest balance at all levels, and an expansion of sub-district education up to secondary school. SAH can be performed regularly and expanded across communities including areas of low-income living due to its low implementation costs. It could also be used as a tool to support the government’s public health initiatives complementing the existing five-year direct health check-up programme. A comparative study of SAH across regions is recommended for future research.

First experience in laparoscopic surgery in low and middle income countries: A systematic review

BACKGROUND Laparoscopic surgery has reduced morbidity and mortality rates,shorter post-operative recovery periods and lower complication rates than open surgery.It is routine practice in high-income countries and is becoming increasingly common in countries with limited resources.However,introducing laparoscopic surgery in low-and-middle-income countries(LMIC)can be expensive and requires resour-ces,equipment,and trainers.AIM To report the challenges and benefits of introducing laparoscopic surgery in LMIC as well as to identify solutions to these challenges for countries with limited finances and resources.METHODS MEDLINE,EMBASE and Cochrane databases were searched for studies reporting first experience in laparoscopic surgery in LMIC.Included studies were published between 1996 and 2022 with full text available in English.Exclusion criteria were studies considering only open surgery,ear,nose,and throat,endoscopy,arthro-scopy,hysteroscopy,cystoscopy,transplant,or bariatric surgery.RESULTS Ten studies out of 3409 screened papers,from eight LMIC were eligible for inclusion in the final analysis,totaling 2497 patients.Most reported challenges were related to costs of equipment and training programmes,equipment pro-blems such as faulty equipment,and access to surgical kits.Training-related challenges were reliance on foreign trainers and lack of locally trained surgeons and theatre staff.The benefits of introducing laparoscopic surgery were economic and clinical,including a reduction in hospital stay,complications,and morbidi-ty/mortality.The introduction of laparoscopic surgery also provided training opportunities for junior doctors.CONCLUSION Despite financial and technical challenges,many studies emphasise the overall benefit of introducing laparoscopic surgery in LMICs such as reduced hospital stay and the related lower cost for patients.While many of the clinical centres in LMICs have proposed practical solutions to the challenges reported,more support is critically required,in particular regarding training.

Digitalization’s Effects on Income Growth and Distribution-Evidence from the CHDES Database

Using the CHDES database,we created the CIDI to comprehensively quantify digital adoption at the individual level and examine digitalization’s impact on individual income.Empirical analysis results indicate that increasing the CIDI by one standard deviation(0.13)improves individual income by 5.93 percentage points,which remains true after a series of endogeneity and robustness tests.In the heterogeneity analysis,we discovered that when digital adoption grows,residents in the countryside and county seats can earn more money through internet business operations and other channels.This helps to decrease the urban-rural income divide,but it has also pushed those digitally skilled into high-paying sectors,widening the income gaps between sectors.In the mechanism analysis,we developed an income function that takes into account the individual level of digitalization to show that digitalization can boost income by increasing working hours or labor participation and adjusting the portfolio of individual material,human,and social capital.In this paper,we have expanded the system for measuring the individual levels of digitalization by offering basic data,research methodology,and policy suggestions for the digital economy’s inclusive development.

How Does E-Commerce Policy Affect Consumption Disparities of Rural Households?-Evidence from China

In the context of China’s ongoing efforts to promote countryside revitalization and facilitate domestic economic circulation,it is of great significance to reduce the consumption disparity among rural households and unleash the consumption potential in the countryside.Based on data from China Family Panel Studies,this paper adopts a staggered difference-in-differences method to assess the impact of the e-commerce to enter rural areas on the consumption disparity among rural households.Findings:the comprehensive demonstration work of promoting e-commerce to enter rural areas has reduced the consumption disparity among rural households through the following mechanisms.Firstly,this policy initiative has mitigated the consumption-inhibiting effect on rural household consumption due to the local market size and external market accessibility by promoting the distribution of consumer goods to villages.Secondly,this policy initiative has also increased the agricultural income of rural households and reduced their consumption disparity by distributing farm produce to cities and enhancing the agricultural income of rural households.Moreover,the work is characterized by inclusive growth and is not susceptible to the“elite capture”phenomenon.

Letter from the Editor-in-Chief Seizing the new opportunities in 2024

Dear readers:No time will be wasted as long as we are making progress.As the New Year bell rings,the beauty industry has officially entered 2024.Looking back on the past year,there are too many stories to recall and remember.In 2023,L‘Oreal bought upmarket beauty brand Aesop;Estee Lauder Group invested in domestic brand code mint;Kering acquired Creed,a high-end fragrance brand.Acquisition and brand expansion have become the representative words of top enterprises.The year of 2023 witnessed the rise of Chinese brands.More and more consumers pay attention to and choose domestic cosmetics,and the quality,innovation and design of domestic products are becoming more mature.And the operating income and net profit of Pelaya,Botanee,and JALA Group rose in an all-round way,and domestic cosmetics achieved initial recovery after the pandemic.

DECODING THE VITALITY OF CHINA’S ECONOMY

With its GDP surpassing RMB 126 trillion,per capita disposable income increasing by 6.1 percent,and 12.44 million urban jobs created,China saw brisk economic recovery last year.These achievements reflect the sound fundamentals of its economy,particularly given the shrinking global trade and increasing geopolitical frictions.

Quality of life and aging

The aging population has far-reaching implications for health,significantly influencing medical care and health policy.According to the World Health Organization(WHO),by 2030,one in six people worldwide will be aged 60 years or older.Furthermore,the population of individuals aged 60 and older is projected to increase from 1 billion in 2020 to 1.4 billion in 2030.By 2050,this population is expected to double,reaching 2.1 billion.Similarly,the number of people aged 80 years and older is anticipated to triple between 2020 and 2050,reaching 426 million[1].This demographic shift toward older adults,known as population aging,initially began in high-income countries but has now extended to low and middle-income nations.By 2050,approximately two-thirds of the world’s population aged 60 and older will reside in these countries.The effects of this aging population pose significant challenges for human health,necessitating substantial societal adjustments[2].