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Accurate measurements of food volume and density are often required as ‘gold standards’ for calibration of image-based dietary assessment and food database development. Currently, there is no specialised laboratory instrument for these measurements. We present the design of a new volume of density (VD) meter to bridge this technological gap.
Our design consists of a turntable, a load sensor, a set of cameras and lights installed on an arc-shaped stationary support, and a microcomputer. It acquires an array of food images, reconstructs a 3D volumetric model, weighs the food and calculates both food volume and density, all in an automatic process controlled by the microcomputer. To adapt to the complex shapes of foods, a new food surface model, derived from the electric field of charged particles, is developed for 3D point cloud reconstruction of either convex or concave food surfaces.
We conducted two experiments to evaluate the VD meter. The first experiment utilised computer-synthesised 3D objects with prescribed convex and concave surfaces of known volumes to investigate different food surface types. The second experiment was based on actual foods with different shapes, colours and textures. Our results indicated that, for synthesised objects, the measurement error of the electric field-based method was <1 %, significantly lower compared with traditional methods. For real-world foods, the measurement error depended on the types of food volumes (detailed discussion included). The largest error was approximately 5 %.
The VD meter provides a new electronic instrument to support advanced research in nutrition science.
Renal fibrosis is common especially in the elderly population. Recently, we found that vitamin D deficiency caused prostatic hyperplasia. This study aimed to investigate whether vitamin D deficiency promotes renal fibrosis and functional impairment. All mice except controls were fed with vitamin D-deficient (VDD) diets, beginning from their early life. The absolute and relative kidney weights on postnatal week 20 were decreased in VDD diet-fed male pups but not in female pups. A mild pathological damage was observed in VDD diet-fed male pups but not in females. Further analysis showed that VDD-induced pathological damage was aggravated, accompanied by renal dysfunction in 40-week-old male pups. An obvious collagen deposition was observed in VDD diet-fed 40-week-old male pups. Moreover, renal α-smooth muscle actin (α-SMA), a marker of epithelial–mesenchymal transition (EMT), and Tgf-β mRNA were up-regulated. The in vitro experiment showed that 1,25-dihydroxyvitamin D3 alleviated transforming growth factor-β1 (TGF-β1)-mediated down-regulation of E-cadherin and inhibited TGF-β1-evoked up-regulation of N-cadherin, vimentin and α-SMA in renal epithelial HK-2 cells. Moreover, 1,25-dihydroxyvitamin D3 suppressed TGF-β1-evoked Smad2/3 phosphorylation in HK-2 cells. These results provide experimental evidence that long-term vitamin D deficiency promotes renal fibrosis and functional impairment, at least partially, through aggravating TGF-β/Smad2/3-mediated EMT in middle-aged male mice.
The present study investigated the association between fibre degradation and the concentration of dissolved molecular hydrogen (H2) in the rumen. Napier grass (NG) silage and corn stover (CS) silage were compared as forages with contrasting structures and degradation patterns. In the first experiment, CS silage had greater 48-h DM, neutral-detergent fibre (NDF) and acid-detergent fibre degradation, and total gas and methane (CH4) volumes, and lower 48-h H2 volume than NG silage in 48-h in vitro incubations. In the second experiment, twenty-four growing beef bulls were fed diets including 55 % (DM basis) NG or CS silages. Bulls fed the CS diet had greater DM intake (DMI), average daily gain, total-tract digestibility of OM and NDF, ruminal dissolved methane (dCH4) concentration and gene copies of protozoa, methanogens, Ruminococcus albus and R. flavefaciens, and had lower ruminal dH2 concentration, and molar proportions of valerate and isovalerate, in comparison with those fed the NG diet. There was a negative correlation between dH2 concentration and NDF digestibility in bulls fed the CS diet, and a lack of relationship between dH2 concentration and NDF digestibility with the NG diet. In summary, the fibre of CS silage was more easily degraded by rumen microorganisms than that of NG silage. Increased dCH4 concentration with the CS diet presumably led to the decreased ruminal dH2 concentration, which may be helpful for fibre degradation and growth of fibrolytic micro-organisms in the rumen.
Aeolian deposits are widely distributed in the middle Yangtze River Basin (YRB), central China. The formation of those aeolian deposits (including aeolian sands and loess deposits) represented the deterioration of local environment. Previous geochronological studies have shown that both aeolian sands and loess began to be deposited in the last interglacial (~100 ka). In this study, a total of four and six accelerator mass spectrometry radiocarbon (AMS 14C) samples were collected from a sand hill and a loess section, respectively, in the Jiujiang area to refine their chronology. Charcoals extracted from bulk samples were employed for AMS 14C dating. The sand layer at the lower part of the HG-C section is sandwiched by two mud layers dated to 26,670–26,285 and 24,480–24,180 cal BP, respectively. Therefore, we infer that aeolian activities in this region started at ~25 ka BP, which was significantly younger than that of previous studies. Meanwhile, thick loess began to deposit leeward of the sand hills in this region. Based on the AMS14C chronology and provenance tracing, we conclude that the loess was essentially the fine-grained aeolian deposits. Our results suggest that topography and vegetation cover have an important effect on the spatial distribution of aeolian deposits in this region.
In this paper, we report a recent theoretical study of the calculation of the binding energy and photoionization cross section of a single dopant in a spherical hollow or core/shell quantum dot taking into account the interaction of the electron with longitudinal optical phonons. Using Frolich approach and Lee-low Pines transformation, we determine the impact of different parameters such as shell thickness and dopant position on the energy and optical response of a bound polaron for two types of ionic II–VI semiconductors CdTe and ZnSe with different phonon coupling constants. Regardless of the material used, the electron–phonon interaction visibly reduces binding energy. For photoionization cross section, a redshift of resonance peaks was found when the effect of phonons is taken into consideration or when the donor is moved away from the shell center. These calculations provide us insights when choosing between materials for optoelectronic applications.
Sexual interaction is an important activity that determines the reproductive schedule of organisms and can ultimately influence the fitness traits of both sexes. Although the influence of sexual interaction on the fitness of females has been extensively determined, little is known about the effects on males, which often have different mating strategies and optimal mating regimes from those of females. To understand how mating regimes (timing and frequency) modulate the fitness in both sexes, we used spider mite (Tetranychus urticae) to investigate the influence of delayed mating and repeated mating on the fitness of male and female. For females, the unmated and the delayed mating females outlived those mated immediately after adult emergence. The repeated mating shortened the lifespan of females that mated at 1-day-old, but not that mated 7-day-old. However, no significant variation in lifespan was observed for males across different mating regimes. We found although delayed mating significantly reduced the daily reproductive rate of the females, there was no significant difference in lifetime reproduction of females across treatments because the delayed mating females increased their reproductive lifespan as a compensation. Our study highlighted that the time and frequency of sexual interaction showed a sex-specific consequence on male and female spider mites, indicating that sexual interaction incurs a higher cost to females which have a much lower optimal mating frequency than males.
The coronavirus disease 2019 (COVID-19) outbreak caused by the severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2 virus) has been sustained in China since December 2019, and has become a pandemic. The mental health of frontline medical staff is a concern. In this study, we aimed to identify the factors influencing medical worker anxiety in China during the COVID-19 outbreak. We conducted a cross-sectional study to estimate the prevalence of anxiety among medical staff in China from 10 February 2020 to 20 February 2020 using the Zung Self-rating Anxiety Scale (SAS) to assess anxiety, with the criteria of normal (⩽49), mild (50–59), moderate (60–70) and severe anxiety (⩾70). We used multivariable linear regression to determine the factors (e.g. having direct contact when treating infected patients, being a medical staff worker from Hubei province, being a suspect case) for anxiety. We also used adjusted models to confirm independent factors for anxiety after adjusting for gender, age, education and marital status. Of 512 medical staff in China, 164 (32.03%) had had direct contact treating infected patients. The prevalence of anxiety was 12.5%, with 53 workers suffering from mild (10.35%), seven workers suffering from moderate (1.36%) and four workers suffering from severe anxiety (0.78%). After adjusting for sociodemographic characteristics (gender, age, education and marital status), medical staff who had had direct contact treating infected patients experienced higher anxiety scores than those who had not had direct contact (β value = 2.33, confidence interval (CI) 0.65–4.00; P = 0.0068). A similar trend was observed in medical staff from Hubei province, compared with those from other parts of China (β value = 3.67, CI 1.44–5.89; P = 0.0013). The most important variable was suspect cases with high anxiety scores, compared to non-suspect cases (β value = 4.44, CI 1.55–7.33; P = 0.0028). In this survey of hospital medical workers during the COVID-19 outbreak in China, we found that study participants experienced anxiety symptoms, especially those who had direct clinical contact with infected patients; as did those in the worst affected areas, including Hubei province; and those who were suspect cases. Governments and healthcare authorities should proactively implement appropriate psychological intervention programmes, to prevent, alleviate or treat increased anxiety.
In this research paper we filter and verify miRNAs which may target silent information regulator homolog 2 (SIRT2) gene and then describe the mechanism whereby miRNA-212 might regulate lipogenic genes in mammary epithelial cell lines via targeting SIRT2. Bioinformatics analysis revealed that the bovine SIRT2 gene is regulated by three miRNAs: miR-212, miR-375 and miR-655. The three miRNAs were verified and screened by qRT-PCR, western blot, and luciferase multiplex verification techniques and only miR-212 was shown to have a targeting relationship with SIRT2. The results of co-transfecting miR-212 and silencing RNA (siRNA) showed that by targeting SIRT2, miR-212 can regulate the expression of fatty acid synthetase (FASN) and sterol regulatory element binding factor 1 (SREBP1) but not peroxisome proliferator-activated receptor gamma (PPARγ). Measurement of triglyceride (TAG) content showed that miR-212 increased the fat content of mammary epithelial cell lines. The study indicates that miR-212 could target and inhibit the expression of the SIRT2 gene to promote lipogenesis in mammary epithelial cell lines.
To gain more comprehensive understanding of metabolic syndrome (Mets) among in general Chinese population.
Cross-sectional study. Mets was defined by three widely accepted definitions including modified Adults Treatment Panel (ATP) III criteria, International Diabetes Federation (IDF) criteria and harmonized definition. Risk factors were evaluated by using multivariate logistic regression.
Nineteen rural villages in northeast China.
The survey was conducted in September 2017 and May 2018 on 10 926 individuals.
According to modified ATP III criteria, IDF criteria and harmonised definition, the overall prevalence of Mets was 41·3 % (95 % CI 40·3, 42·2), 34·2 % (95 % CI 33·2, 35·1) and 44·1 % (95 % CI 43·1, 45·1), respectively. Females had a higher prevalence, and elevated blood pressure was the most frequent. Age, female sex, non-peasant worker, higher BMI and lower-annual income were independent risk factors of Mets in all three definitions (all ps < 0·05). Based on modified ATP III criteria and harmonised definition, heavy drinking was positively correlated with Mets. In contrast, former drinking was inversely associated with Mets.
Mets is highly prevalent in rural areas of northeast China. Its independent risk factors include higher age, female sex, non-peasantry worker, higher BMI and lower-annual income. Modified ATP III criteria and harmonised definition may be superior definitions of Mets.
Social anxiety disorder (SAD) is a prevalent mental disorder diagnosed in childhood and adolescence. Theories regarding brain development and SAD suggest a close link between neurodevelopmental dysfunction at the adolescent juncture and SAD, but direct evidence is rare. This study aims to examine brain structural abnormalities in adolescents with SAD.
High-resolution T1-weighted images were obtained from 31 adolescents with SAD (15–17 years) and 42 matching healthy controls (HC). We evaluated symptom severity with the Social Anxiety Scale for Children (SASC) and the Screen for Child Anxiety Related Emotional Disorders (SCARED). We used voxel-based morphometry analysis to detect regional gray matter volume abnormalities and structural co-variance analysis to investigate inter-regional coordination patterns.
We found significantly higher gray matter volume in the orbitofrontal cortex (OFC) and the insula in adolescents with SAD compared to HC. We also observed significant co-variance of the gray matter volume between the OFC and amygdala, and the OFC and insula in HC, but these co-variance relationships diminished in SAD.
These findings provide the first evidence that the brain structural deficits in adolescents with SAD are not only in the core regions of the fronto-limbic system, but also represented by the diminished coordination in the development of these regions. The delayed and unsynchronized development pattern of the fronto-limbic system supports SAD as an adolescent-sensitive developmental mental disorder.
In the laser plasma interaction of quantum electrodynamics (QED)-dominated regime, γ-rays are generated due to synchrotron radiation from high-energy electrons traveling in a strong background electromagnetic field. With the aid of 2D particle-in-cell code including QED physics, we investigate the preplasma effect on the γ-ray generation during the interaction between an ultraintense laser pulse and solid targets. We found that with the increasing preplasma scale length, the γ-ray emission is enhanced significantly and finally reaches a steady state. Meanwhile, the γ-ray beam becomes collimated. This shows that, in some cases, the preplasmas will be piled up acting as a plasma mirror in the underdense preplasma region, where the γ-rays are produced by the collision between the forward electrons and the reflected laser fields from the piled plasma. The piled plasma plays the same role as the usual reflection mirror made from a solid target. Thus, a single solid target with proper scale length preplasma can serve as a manufactural and robust γ-ray source.
When the average intermolecular distance is comparable to the size of gas molecules, the Boltzmann equation, based on the dilute gas assumption, becomes invalid. The Enskog equation was developed to account for this finite size effect that makes the collision non-local and increases the collision frequency. However, it is time-consuming to solve the Enskog equation due to its complicated structure of collision operator and high dimensionality. In this work, on the basis of the Shakhov model, a gas kinetic model is proposed to simplify the Enskog equation for non-ideal monatomic dense gases. The accuracy of the proposed Shakhov–Enskog model is assessed by comparing its solutions of the normal shock wave structures with the results of the Enskog equation obtained by the fast spectral method. It is shown that the Shakhov–Enskog model is able to describe non-equilibrium flow of dense gases, when the maximum local mean free path of gas molecules is still greater than the size of a molecular diameter. The accuracy and efficiency of the present model enable simulations of non-equilibrium flow of dense gases for practical applications.
Epidemiological data for Toxoplasma gondii regarding malignancy have gained increasing attention; however, the information about T. gondii infection among children with malignant lymphoma (ML) in China is unclear. Therefore, 314 children with lymphoma and 314 healthy children, age- and gender-matched, were recruited to estimate the seroprevalence of T. gondii in the participants and identify the risk factors of infection. Blood samples from all participants were collected and examined for T. gondii IgG and IgM antibodies using ELISA. The results showed that the overall seroprevalence of T. gondii antibodies (including IgG and/or IgM) in ML patients and healthy controls was 19.8% and 9.9%, respectively. Contact with the cats, consumption of oysters and history of chemotherapy were estimated to be the risk factors for T. gondii infection in children with lymphoma by multivariable logistic regression analysis, whereas in healthy children, contact with cats and consumption of oysters were the risk factors. Moreover, among various histological types of lymphoma, individuals with NK/T-cell lymphoma, B-small lymphocytic lymphoma, marginal zone B-lymphoma and Hodgkin's lymphoma had a higher seroprevalence than healthy controls (P < 0.05). These findings indicated the high prevalence of T. gondii infection in children with lymphoma, and hence, efforts should be performed to evaluate the effect of the infection further in lymphoma patients.
The microbiota–gut–brain axis, especially the microbial tryptophan (Trp) biosynthesis and metabolism pathway (MiTBamp), may play a critical role in the pathogenesis of major depressive disorder (MDD). However, studies on the MiTBamp in MDD are lacking. The aim of the present study was to analyze the gut microbiota composition and the MiTBamp in MDD patients.
We performed shotgun metagenomic sequencing of stool samples from 26 MDD patients and 29 healthy controls (HCs). In addition to the microbiota community and the MiTBamp analyses, we also built a classification based on the Random Forests (RF) and Boruta algorithm to identify the gut microbiota as biomarkers for MDD.
The Bacteroidetes abundance was strongly reduced whereas that of Actinobacteria was significantly increased in the MDD patients compared with the abundance in the HCs. Most noteworthy, the MDD patients had increased levels of Bifidobacterium, which is commonly used as a probiotic. Four Kyoto Encyclopedia of Genes and Genomes (KEGG) orthologies (KOs) (K01817, K11358, K01626, K01667) abundances in the MiTBamp were significantly lower in the MDD group. Furthermore, we found a negative correlation between the K01626 abundance and the HAMD scores in the MDD group. Finally, RF classification at the genus level can achieve an area under the receiver operating characteristic curve of 0.890.
The present findings enabled a better understanding of the changes in gut microbiota and the related Trp pathway in MDD. Alterations of the gut microbiota may have the potential as biomarkers for distinguishing MDD patients form HCs.
We established a mastitis model using exogenous infection of the mammary gland of Chinese Holstein cows with Staphylococcus aureus and extracted total RNA from S. aureus-infected and healthy mammary quarters. Differential expression of genes due to mastitis was evaluated using Affymetrix technology and results revealed a total of 1230 differentially expressed mRNAs. A subset of affected genes was verified via Q-PCR and pathway analysis. In addition, Solexa high-throughput sequencing technology was used to analyze profiles of miRNA in infected and healthy quarters. These analyses revealed a total of 52 differentially expressed miRNAs. A subset of those results was verified via Q-PCR. Bioinformatics techniques were used to predict and analyze the correlations among differentially expressed miRNA and mRNA. Results revealed a total of 329 pairs of negatively associated miRNA/mRNA, with 31 upregulated pairs of mRNA and 298 downregulated pairs of mRNA. Differential expression of miR-15a and interleukin-1 receptor-associated kinase-like 2 (IRAK2), were evaluated by western blot and luciferase reporter assays. We conclude that miR-15a and miR-15a target genes (IRAK2) constitute potential miRNA–mRNA regulatory pairs for use as biomarkers to predict a mastitis response.
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.
Disturbances in lipid metabolism are at the core of several health issues facing modern society, including fatty liver and obesity. The sterol regulatory element-binding protein 1 (SREBP-1) is one important transcription factor regulating lipid metabolism, but the relevant mechanism still remains unknown. The present study determined the transcriptional regulation of SREBP-1 and its target genes (including acetyl-CoA carboxylase α (accα), fatty acid synthase (fas) and stearoyl-CoA desaturase 1 (scd1)) in a freshwater teleost, grass carp Ctenopharyngodon idella. We cloned and characterised the 1988 bp, 2043 bp, 1632 bp and 1889 bp sequences of srebp-1, accα, scd1 and fas promoters, respectively. A cluster of putative binding sites of transcription factors, such as specific protein, yin yang 1, nuclear factor Y, sterol response elements (SRE) and enhancer box (E-box) element, were predicted on their promoter regions. Overexpression of nSREBP-1 reduced srebp-1 promoter activity, increased scd1 and fas promoter activity but did not influence accα promoter activity. The site-mutation and electrophoretic mobility shift assay analysis indicated that srebp-1, fas and scd1 promoters, but not accα promoter, possessed SRE. In Ctenopharyngodon idella kidney (CIK) cells of grass carp, nSREBP-1 overexpression significantly reduced srebp-1 mRNA expression and up-regulated miR-29 mRNA expression. The 3′UTR of srebp-1 possessed the potential miR-29 binding site and miR-29 up-regulated the luciferase activity of srebp-1 3′UTR and srebp-1 mRNA expression, implying a self-activating loop of SREBP-1 and miR-29 in grass carp. Based on the above-mentioned results, we found two novel transcriptional mechanisms for SREBP-1 in grass carp: (1) the auto-regulation sited on the SREBP-1 promoter regions was suppressive and (2) there was a self-activating loop of SREBP-1 and miR-29.
We assessed inheritance of resistance to sugarcane brown rust (Puccinia melanocephala) in selfing F1 populations of wild sugarcane germplasm Erianthus rockii ‘Yundian 95-19’ and E. rockii ‘Yundian 95-20’. We tested parent and selfing F1 individuals for the brown rust resistance gene, Bru1, that has been shown to confer resistance to brown rust in sugarcane. The Bru1 gene was not detected in E. rockii ‘Yundian 95-19’, E. rockii ‘Yundian 95-20’ or their selfing F1 individuals, and we found there was segregation of resistance in the two selfing F1 populations (segregation ratio: 3:1). The results confirmed resistance in E. rockii ‘Yundian 95-19’ and E. rockii ‘Yundian 95-20’ to sugarcane brown rust is controlled by a novel, single dominant gene.
Determining the shape of the stellar initial mass function (IMF) and whether it is constant or varies in space and time is the Holy Grail of modern astrophysics, with profound implications for all theories of star and galaxy formation. On a theoretical ground, the extreme conditions for star formation (SF) encountered in the most powerful starbursts in the Universe are expected to favour the formation of massive stars. Direct methods of IMF determination, however, cannot probe such systems, because of the severe dust obscuration affecting their starlight. The next best option is to observe CNO bearing molecules in the interstellar medium at millimetre/ submillimetre wavelengths, which, in principle, provides the best indirect evidence for IMF variations. In this contribution, we present our recent findings on this issue. First, we reassess the roles of different types of stars in the production of CNO isotopes. Then, we calibrate a proprietary chemical evolution code using Milky Way data from the literature, and extend it to discuss extragalactic data. We show that, though significant uncertainties still hamper our knowledge of the evolution of CNO isotopes in galaxies, compelling evidence for an IMF skewed towards high-mass stars can be found for galaxy-wide starbursts. In particular, we analyse a sample of submillimetre galaxies observed by us with the Atacama Large Millimetre Array at the peak of the SF activity of the Universe, for which we measure 13C/18O⋍1. This isotope ratio is especially sensitive to IMF variations, and is little affected by observational uncertainties. At the end, ongoing developments of our work are briefly outlined.