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Listeriosis is a rare but serious foodborne disease caused by Listeria monocytogenes. This matched case–control study (1:1 ratio) aimed to identify the risk factors associated with food consumption and food-handling habits for the occurrence of sporadic listeriosis in Beijing, China. Cases were defined as patients from whom Listeria was isolated, in addition to the presence of symptoms, including fever, bacteraemia, sepsis and other clinical manifestations corresponding to listeriosis, which were reported via the Beijing Foodborne Disease Surveillance System. Basic patient information and possible risk factors associated with food consumption and food-handling habits were collected through face-to-face interviews. One hundred and six cases were enrolled from 1 January 2018 to 31 December 2020, including 52 perinatal cases and 54 non-perinatal cases. In the non-perinatal group, the consumption of Chinese cold dishes increased the risk of infection by 3.43-fold (95% confidence interval 1.27–9.25, χ2 = 5.92, P = 0.02). In the perinatal group, the risk of infection reduced by 95.2% when raw and cooked foods were well-separated (χ2 = 5.11, P = 0.02). These findings provide important scientific evidence for preventing infection by L. monocytogenes and improving the dissemination of advice regarding food safety for vulnerable populations.
Nutritional Risk Screening index is a standard tool to assess nutritional risk, but epidemiological data are scarce on controlling nutritional status (CONUT) as a prognostic marker in acute haemorrhagic stroke (AHS). We aimed to explore whether the CONUT may predict a 3-month functional outcome in AHS. In total, 349 Chinese patients with incident AHS were consecutively recruited, and their malnutrition risks were determined using a high CONUT score of ≥ 2. The cohort patients were divided into high-CONUT (≥ 2) and low-CONUT (< 2) groups, and primary outcomes were a poor functional prognosis defined as the modified Rankin Scale (mRS) score of ≥ 3 at post-discharge for 3 months. Odds ratios (OR) with 95 % confidence intervals (CI) for the poor functional prognosis at post-discharge were estimated by using a logistic analysis with additional adjustments for unbalanced variables between the high-CONUT and low-CONUT groups. A total of 328 patients (60·38 ± 12·83 years; 66·77 % male) completed the mRS assessment at post-discharge for 3 months, with 172 patients at malnutrition risk at admission and 104 patients with a poor prognosis. The levels of total cholesterol and total lymphocyte counts were significantly lower in high-CONUT patients than low-CONUT patients (P = 0·012 and < 0·001, respectively). At 3-month post discharge, there was a greater risk for the poor outcome in the high-CONUT compared with the low-CONUT patients at admission (OR: 2·32, 95 % CI: 1·28, 4·17). High-CONUT scores independently predict a 3-month poor prognosis in AHS, which helps to identify those who need additional nutritional managements.
The present study evaluated effects of dietary supplementation with tryptophan (Trp) on muscle growth, protein synthesis and antioxidant capacity in hybrid catfish Pelteobagrus vachelli♀ × Leiocassis longirostris♂. Fish were fed six different diets containing 2·6 (control), 3·1, 3·7, 4·2, 4·7 and 5·6 g Trp/kg diet for 56 d, respectively. Results showed that dietary Trp significantly (1) improved muscle protein content, fibre density and frequency of fibre diameter; (2) up-regulated the mRNA levels of PCNA, myf5, MyoD1, MyoG, MRF4, IGF-I, IGF-II, IGF-IR, PIK3Ca, TOR, 4EBP1 and S6K1; (3) increased phosphorylation levels of AKT, TOR and S6K1; (4) decreased contents of MDA and PC, and increased activities of CAT, GST, GR, ASA and AHR; (5) up-regulated mRNA levels of CuZnSOD, CAT, GST, GPx, GCLC and Nrf2, and decreased Keap1 mRNA level; (6) increased nuclear Nrf2 protein level and the intranuclear antioxidant response element-binding ability, and reduced Keap1 protein level. These results indicated that dietary Trp improved muscle growth, protein synthesis as well as antioxidant capacity, which might be partly related to myogenic regulatory factors, IGF/PIK3Ca/AKT/TOR and Keap1/Nrf2 signalling pathways. Finally, based on the quadratic regression analysis of muscle protein and MDA contents, the optimal Trp requirements of hybrid catfish (21·82–39·64 g) were estimated to be 3·94 and 3·93 g Trp/kg diet (9·57 and 9·54 g/kg of dietary protein), respectively.
The staining procedure is critical for investigating intra- and extra-cellular ultrastructure of microorganisms by transmission electron microscopy (TEM). Here, we propose a new ultra-low lead staining (ULLS) technique for preparing the ultrathin sections for TEM analysis. Sections of Enterobacter sp. (bacteria), Aspergillus niger (filamentous fungi), Rhodotorula mucilaginosa (fungi), and Chlamydomonas reinhardtii (microalgae) were tested. Compared with the sections prepared by the typical double-staining technique, ULLS-based sections showed evident advantages: (i) the staining process only required the addition of Pb(NO3)2; (ii) the Pb level during incubation was set as low as 1 mg/L, which had negligible toxicity to most microbial cells; (iii) the Pb cations were added during microbial culture, which avoided complicated sample preparation as in typical double staining. Taking C. reinhardtii as an example, the ULLS technique allowed fine investigation of microbial ultrastructure, e.g., starch granule, mitochondrion, Golgi apparatus, vacuole, and vesicle. Meanwhile, the physiological processes of the cells such as cell lysis and exocytosis were successfully captured, with relatively high contrast. This study hence shows a bright future on preparation of the high-quality ultrathin sections of microbial cells by the ULLS technique.
On 1 February 2021, under the command of General Min Aung Hlaing, Myanmar's military initiated a coup, apparently drawing to a close Myanmar's ten-year experiment with democratic rule. State Counsellor Aung San Suu Kyi and President Win Myint were arrested along with other elected officials. Mass protests against the coup ensued, led by Gen Z youths who shaped a values-based democratic revolutionary movement that in character is anti-military regime, anti-China influence, anti-authoritarian, anti-racist, and anti-sexist. Women and minorities have been at the forefront, organizing protests, shaping campaigns, and engaging sectors of society that in the past had been relegated to the periphery of national politics. The protests were broadcast to local and international audiences through social media. Simultaneously, a civil disobedience movement (CDM) arose in the shape of a massive strike mostly led by civil servants. CDM is non-violent and acephalous, a broad 'society against the state' movement too large and diffuse for the military to target and dismantle. Semi-autonomous administrative zones in the name of Pa-a-pha or civil administrative organizations emerged out of spontaneously organized neighbourhood watches at the ward and village levels, effectively forming a parallel governance system to the military state. Anti-coup protests moved decisively away from calls for the release of Aung San Suu Kyi and other elected political leaders, or for a return to democracy under the 2008 constitution. Instead, it evolved towards greater inclusivity of all Myanmar peoples in pursuit of a more robust federal democracy. A group of fifteen elected parliamentarians, representing the ideals of Gen Z youths, formed a shadow government called the Committee Representing the Pyidaungsu Hluttaw (CRPH) on 5 February 2021. On 1 March the CRPH declared the military governing body, the State Administrative Council (SAC), a 'terrorist group', and on 31 March, it declared the military's 2008 constitution abolished. Gen Z's protests have accomplished what has been elusive to prior generations of anti-regime movements and uprisings. They have severed the Bamar Buddhist nationalist narrative that has gripped state society relations and the military's ideological control over the political landscape, substituting for it an inclusive democratic ideology.
• On 1 February 2021, under the command of General Min Aung Hlaing, Myanmar's military initiated a coup, apparently drawing to a close Myanmar's ten-year experiment with democratic rule. State Counsellor Aung San Suu Kyi and President Win Myint were arrested along with other elected officials.
• Mass protests against the coup ensued, led by Gen Z youths who shaped a values-based democratic revolutionary movement that in character is anti-military regime, anti-China influence, anti-authoritarian, anti-racist, and anti-sexist. Women and minorities have been at the forefront, organizing protests, shaping campaigns, and engaging sectors of society that in the past had been relegated to the periphery of national politics. The protests were broadcast to local and international audiences through social media.
• Simultaneously, a civil disobedience movement (CDM) arose in the shape of a massive strike mostly led by civil servants. CDM is non-violent and acephalous, a broad “society against the state” movement too large and diffuse for the military to target and dismantle. Semi-autonomous administrative zones in the name of Pa-a-pha or civil administrative organizations emerged out of spontaneously organized neighbourhood watches at the ward and village levels, effectively forming a parallel governance system to the military state.
• Anti-coup protests moved decisively away from calls for the release of Aung San Suu Kyi and other elected political leaders, or for a return to democracy under the 2008 constitution. Instead, it evolved towards greater inclusivity of all Myanmar peoples in pursuit of a more robust federal democracy. A group of fifteen elected parliamentarians, representing the ideals of Gen Z youths, formed a shadow government called the Committee Representing the Pyidaungsu Hluttaw (CRPH) on 5 February 2021. On 1 March the CRPH declared the military governing body, the State Administrative Council (SAC), a “terrorist group”, and on 31 March, it declared the military's 2008 constitution abolished.
• Gen Z's protests have accomplished what has been elusive to prior generations of anti-regime movements and uprisings. They have severed the Bamar Buddhist nationalist narrative that has gripped state society relations and the military's ideological control over the political landscape, substituting for it an inclusive democratic ideology.
On 1 February 2021, the opening day of the new Parliament elected in November 2020, Sr. Gen. Min Aung Hlaing, commander-in-chief of the Myanmar Armed Forces, or Tatmadaw, launched a coup overthrowing the country's democratic government. The military declared a newly formed “State Administration Council” as the interim governing body, reserving to the Tatmadaw Commander-in-Chief the “exercise of legislative power by himself or by a body including him”. The arrest of President Win Myint and State Counsellor Aung San Suu Kyi, alongside other National League for Democracy (NLD) party members, writers, student leaders, activists, and monks, prompted a committee of fifteen ousted elected lawmakers to form a government-in-waiting under the name of the Committee Representing the Pyidaungsu Hluttaw (CRPH) and calling for Myanmar citizens and the international community to help restore democracy.
A leaderless youth movement identified in Myanmar as “Gen Z” has since been shaping the anti-coup movement by amplifying a wide array of civil society and minority voices. Their youthful exuberance and refusal to accept military rule has encouraged resistance from all sectors of society and has united the Bamar majority and ethnic minorities in a common anti-regime movement. Gen Z's protests have accomplished what has been elusive to prior generations of anti-regime movements and uprisings. They have severed the Bamar Buddhist nationalist narrative that has gripped state-society relations and facilitated the military's ideological control over the political landscape. Gen Z has challenged attitudes and values that have restricted participation in national politics to a patriarchal, gerontocratic, and Bamar Buddhist majority. Emphasizing values that draw from global democratic ideals and imaginaries as well as universal Buddhist ethics, Gen Z has guided a movement of movements that is leaderless, emphasizes horizontal relations (rather than hierarchical ones), and accentuates a social justice orientation inclusive of all members of society.
This paper charts descriptively and analytically the first two months of Myanmar's 2021 anti-coup protests. Revolutionary movements are messy, processual, and dialectical; we aim to capture a moment in an evolving situation, infusing our inquiry with historical context and genealogical reasoning so as to draw out certain features of particular political and cultural salience.
The economic, political, strategic and cultural dynamism in Southeast Asia has gained added relevance in recent years with the spectacular rise of giant economies in East and South Asia. This has drawn greater attention to the region and to the enhanced role it now plays in international relations and global economics.
The sustained effort made by Southeast Asian nations since 1967 towards a peaceful and gradual integration of their economies has had indubitable success, and perhaps as a consequence of this, most of these countries are undergoing deep political and social changes domestically and are constructing innovative solutions to meet new international challenges. Big Power tensions continue to be played out in the neighbourhood despite the tradition of neutrality exercised by the Association of Southeast Asian Nations (ASEAN).
The Trends in Southeast Asia series acts as a platform for serious analyses by selected authors who are experts in their fields. It is aimed at encouraging policymakers and scholars to contemplate the diversity and dynamism of this exciting region.
To investigate the vision loss burden due to vitamin A deficiency (VAD) at the global, regional and national levels by year, age, sex and socio-economic status using prevalence and years lived with disability (YLD).
Prevalence and YLD data were extracted from the Global Burden of Disease (GBD) Study 2017. The association of age-standardised YLD rates and human development index (HDI) was tested by Pearson correlation and linear regression analyses. The Gini coefficient and concentration index (CI) were calculated to demonstrate the trends in between-country inequality in vision loss burden due to VAD.
Participants:
All participants met the GBD inclusion criteria.
Results:
The age-standardised prevalence rate increased by 9·2 %, while the age-standardised YLD rates rose by 10·8 % from 1990 to 2017. Notably, the vision loss burden caused by VAD showed a declining trend since 2014. The vision loss burden was more concentrated in the post-neonatal age group and decreased with increasing age. The age-standardised YLD rates were inversely correlated with HDI (r = –0·2417, P = 0·0084). The CI and Gini coefficients indicated that socio-economic-related and between-country inequality declined from 2000 to 2017. VAD was the eighth leading cause of the age-standardised prevalence rate and ninth leading cause of age-standardised YLD rate among fifteen causes of vision loss in 2017.
Conclusion:
VAD has become one of the significant leading causes of vision loss globally. Efforts to control vision impairment related to VAD are needed, especially for children in countries with lower socio-economic status.
Zoning texture in sphalerite has been described in many studies, although its genesis and ore formation process are poorly constrained. In this investigation, we compare the in situ trace element and isotopic composition of colour-zoned sphalerites from Nayongzhi, South China, to explain the zoning growth process. Petrographic observations identified two broad types of zoned sphalerite, core–rim (CR) and core–mantle–rim (CMR) textures. Each zoned sphalerite displays two or three colour zones, including brown core, light colour bands and/or pale-yellow zones. In situ laser ablation inductively coupled plasma mass spectrometry trace-element analyses show that the three colour zones display variable trace-element compositions. Brown cores exhibit distinctly high Mn, Fe, Co, Ge, Tl and Pb concentrations, whereas pale-yellow and light colour zones have elevated Ga, Cd, Sn, In and Sb concentrations. Copper, Sb, In and Sn show slight variations between pale-yellow and light zones, the latter having higher In and Sn, but lower Cu and Sb abundances. Given the low concentration range of Pb, Ge, Tl, Mn Sb, Cd, etc., the colour of sphalerite is attributed mainly to Fe compositional variation. The δ34S values of sphalerite from Nayongzhi range from +22.3 to +27.9‰, suggesting reduced sulfur was generated by thermochemical sulfate reduction of marine sulfate in ore-hosted strata. Single-crystal colour-zoned sphalerite exhibits intracrystalline δ34S variation (up to 4.3‰), which is attributed to the δ34S composition of H2S in the original fluid. The lack of correlation between trace elements and δ34S values indicates episodic ore solution influxes and mixes with the reduced sulfur-rich fluid derived from the aquifers of the ore-hosted strata, which play a key role in the formation of the zoned Nayongzhi sphalerite. In conclusion, in situ trace element and S isotope studies of zoned sphalerite crystals might provide insight into the ore-forming process of MVT deposits.
The aim of this study was to assess the current status of disease-related knowledge and to analyze the relationship among the general condition, illness perception, and psychological status of patients with coronavirus disease 2019 (COVID-19).
Methods:
A hospital-based cross-sectional study was conducted on 118 patients using convenience sampling. The general questionnaire, disease-related knowledge questionnaire of COVID-19, Illness Perception Questionnaire (IPQ), and Profile of Mood States (POMS) were used to measure the current status of participants.
Results:
The overall average score of the disease-related knowledge of patients with COVID-19 was (79.19 ± 14.25), the self-care situation was positively correlated with knowledge of prevention and control (r = 0.265; P = 0.004) and total score of disease-related knowledge (r = 0.206; P = 0.025); the degree of anxiety was negatively correlated with the knowledge of diagnosis and treatment (r = −0.182; P = 0.049). The score of disease-related knowledge was negatively correlated with negative cognition (volatility, consequences, emotional statements) and negative emotions (tension, fatigue, depression) (P < 0.05); positively correlated with positive cognition (disease coherence) and positive emotion (self-esteem) (P < 0.05).
Conclusions:
It was recommended that we should pay more attention to the elderly and low-income groups, and increase the knowledge about diagnosis and treatment of COVID-19 and self-care in the future health education for patients.
The high overall plant-based diet index (PDI) is considered to protect against type 2 diabetes in the general population. However, whether the PDI affects gestational diabetes mellitus (GDM) risk among pregnant women is still unclear. We evaluated the association between PDI and GDM risk based on a Chinese large prospective cohort – the Tongji Maternal and Child Health Cohort. Dietary data were collected at 13–28 weeks of pregnancy by a validated semi-quantitative FFQ. The PDI was obtained by assigning plant food groups positive scores while assigning animal food groups reverse scores. GDM was diagnosed by a 75 g 2-h oral glucose tolerance test at 24–28 weeks of gestation. Logistic regression models were fitted to estimate OR of GDM, with associated 95 % CI, comparing women in different PDI quartiles. Among the total 2099 participants, 169 (8·1 %) were diagnosed with GDM. The PDI ranged from 21·0 to 52·0 with a median of 36·0 (interquartile range (IQR) 33·0–39·0). After adjusting for social-demographic characteristics and lifestyle factors etc., the participants with the highest quartile of PDI were associated with 57 % reduced odds of GDM compared with women in the lowest quartile of PDI (adjusted OR 0·43; 95 % CI 0·24, 0·77; Pfor trend = 0·005). An IQR increment in PDI was associated with 29 % decreased odds of GDM (adjusted OR 0·71; 95 % CI 0·56, 0·90). Findings suggest that adopting a plant-based diet during pregnancy could reduce GDM risk among Chinese women, which may be valuable for dietary counselling during pregnancy.
Power scaling based on traditional ytterbium-doped fibers (YDFs) is limited by optical nonlinear effects and transverse mode instability (TMI) in high-power fiber lasers. Here, we propose a novel long tapered fiber with a constant cladding and tapered core (CCTC) along its axis direction. The tapered-core region of the fiber is designed to enhance the stimulated Raman scattering (SRS) threshold and suppress higher-order mode resonance in the laser cavity. The CCTC YDF was fabricated successfully with a modified chemical vapor deposition (MCVD) method combined with solution doping technology, which has a cladding diameter of 400 μm and a varying core with a diameter of ~24 μm at both ends and ~31 μm in the middle. To test the performance of the CCTC fiber during high-power operation, an all-fiber laser oscillator based on a CCTC YDF was investigated experimentally. As a result, a maximum output power of 3.42 kW was achieved with an optical-to-optical efficiency of 55.2%, although the TMI effect was observed at an output power of ~3.12 kW. The measured beam quality (M2 factor) was ~1.7, and no sign of the Raman component was observed in the spectrum. We believe that CCTC YDF has great potential to simultaneously mitigate the SRS and TMI effects, and further power scaling is promising by optimizing the structure of the YDF.
In the present study, we analysed the effects of SNP rs174547 (T/C) in the fatty acid desaturase 1 (FADS1) gene on long-chain PUFA levels. Four databases were searched to retrieve related literature with keywords such as fatty acid (FA), SNP, FADS1 and rs174547. A meta-analysis of the data was performed using Stata12.0 software, including summary statistics, test for heterogeneity, evaluation of publication bias, subgroup analysis and sensitivity analysis. The associations between rs174547 in FADS1 and seven types of FA, and Δ-5 (D5D) and Δ-6 fatty acid desaturase (D6D) activity were assessed based on the pooled results from eleven papers. A total of 3713 individuals (1529 TT and 2184 TC + CC) were included. The results demonstrated that minor C allele carriers of rs174547 had higher linoleic acid (LA; P < 0·001) and α-linolenic acid (P = 0·020) levels, lower γ-linolenic acid (GLA; P = 0·001) and arachidonic acid (P = 0·024) levels, and lower D5D (P = 0·005) and D6D (P = 0·004) activities than the TT genotype group. Stratification analysis showed that minor C allele carriers of rs174547 had higher LA and lower GLA levels and lower D6D activities in plasma (LA, P < 0·001; GLA, P < 0·001; D6D activity, P < 0·001) samples and in Asian populations (LA, P < 0·001; GLA, P = 0·001; D6D activity, P = 0·001) than the TT genotype group. In conclusion, minor C allele carriers of the SNP rs174547 were associated with decreased activity of D5D and D6D.
The case-mix method involves combining cases with similar complexities and medical services. The process of treating one episode of the disease and receiving treatment is the research unit, thus achieving different medical units. The feasibility of the calculation method is verified by calculating the public hospital consumption ratio, medical income, health materials expenditure indicators, and the differences between the various types of surgical combinations. A decision-making basis can then be provided for the creation of government indicator standards.
Methods
Medical records and data on the expenditure of medical consumables for the first and fourth quarters of 2017 were collected from seven third-class provincial hospitals. The medical consumption ratio for different diseases and surgical methods was calculated for the case-mix groups using a weighting method. Data were analyzed by descriptive statistics and the independent samples t-test.
Results
There were significant differences in the proportions of combined use for different types of diseases. The same combination also had significant differences between different hospitals. In the fourth quarter of 2017, the operating group's consumption ratio was significantly lower than in the first quarter (p = 0.000).
Conclusions
It is reasonable to calculate the proportion of consumption by combined weighted analysis, which is also fairer for hospitals with better technical levels. This calculation method can be used by governments to manage the use and cost of medical consumables in hospitals.
In this research communication, a cell model with elevated β-CASEIN synthesis was established by stimulating bovine mammary epithelial cells with 0.6 mM methionine, and the genome-wide gene expression profiles of methionine-stimulated cells and untreated cells were investigated by RNA sequencing. A total of 458 differentially expressed genes (DEGs; 219 upregulated and 239 downregulated) were identified between the two groups. Gene Ontology (GO) analysis showed that the two highest-ranked GO terms in ‘molecular function’ category were ‘binding’ and ‘catalytic activity’, suggesting that milk protein synthesis in methionine-stimulated cells requires induction of gene expression to increase metabolic activity. Kyoto Encyclopedia of Genes and Genomes analysis revealed that within the ‘environmental information processing’ category, the subcategory that is most highly enriched for DEGs was ‘signal transduction’. cGMP-PKG, Rap1, calcium, cAMP, PI3K-AKT, MAPK, and JAK-STAT are the pathways with the highest number of DEGs, suggesting that these signaling pathways have potential roles in mediating methionine-induced milk protein synthesis in bovine mammary epithelial cells. This study provides valuable insights into the physiological and metabolic adaptations in cells stimulated with methionine. Understanding the regulation of this transition is essential for effective intervention in the lactation process.
In this study, we have spectroscopically investigated the plasma generated by a Q-switched Nd:YAG laser operating at its fundamental wavelength of 1064 nm focused on magnesium (Mg) and titanium (Ti) target samples in the air under atmospheric pressure. We employed circular cavities of radii (2.5, 3.0, and 3.5 mm) and a square cavity to investigate the cavity confinement effect on the spectral emission intensities of the plasmas. We observed that the circular cavity of radius 2.5 mm had the maximum signal enhancement, and this can be attributed to the compression of the plasma and reheating by the reflected shock waves. The maximum enhancement factor of the Mg I-518.4 nm line was reached at approximately 3.8, 3.4, and 2.8 with a circular cavity of radius 2.5, 3.0, and 3.5 mm, respectively, at a delay time of 350 ns and a laser energy of 350 mJ. By applying varying external magnetic fields (0.47, 0.62, 0.91, and 1.23 T) across the generated plasma, the plasma parameters such as electron temperature and number density have been investigated. From our results, we observed that the radius of the cavity had a tremendous effect on the enhancement of the emission signal intensities. We also found that the increase in the electron temperature and the number density can be attributed to the increase in the applied magnetic field and the laser energy. From our calculations, the value of β, which was less than 1 for all the cases, confirms that there was a plasma confinement at the presence of the magnetic field.
The experiment was conducted to investigate the effects of dietary threonine (Thr) on growth performance and muscle growth, protein synthesis and antioxidant-related signalling pathways of hybrid catfish Pelteobagrus vachelli♀ × Leiocassis longirostris♂. A total of 1200 fish (14·19 (se 0·13) g) were randomly distributed into six groups with four replicates each, fed six diets with graded level of Thr (9·5, 11·5, 13·5, 15·4, 17·4 and 19·3 g/kg diets) for 56 d. Results showed (P < 0·05) that dietary Thr (1) increased percentage weight gain, specific growth rate, feed efficiency and protein efficiency ratio; (2) up-regulated growth hormone (GH), insulin-like growth factor 1 (IGF-1), proliferating cell nuclear antigen, myogenic regulation factors (MyoD, Myf5, MyoG and Mrf4) and myosin heavy chain (MyHC) mRNA levels; (3) increased muscle protein content via regulating the protein kinase B/target of rapamycin signalling pathway and (4) decreased malondialdehyde and protein carbonyl contents, increased catalase, glutathione-S-transferase, glutathione reductase and GSH activities, up-regulated mRNA levels of antioxidant enzymes related to NFE2-related factor 2 and γ-glutamylcysteine ligase catalytic subunit. These results suggest that Thr has a potential role to improve muscle growth and protein synthesis, which might be due to the regulation of GH-IGF system, muscle growth-related gene, antioxidative capacity and protein synthesis-related signalling pathways. Based on the quadratic regression analysis of specific growth rate, the Thr requirement of hybrid catfish (14·19–25·77 g) was estimated to be 13·77 g/kg of the diet (33·40 g/kg of dietary protein).
The Sichuan–Yunnan–Guizhou (SYG) Pb–Zn metallogenic province is one of the most productive areas of Pb–Zn resources in China. The Fule deposit occurs in Permian carbonate and contains Pb–Zn reserves exceeding 1 Mt. To investigate the sulphur source, in situ S isotopic analysis of sphalerite and pyrite was carried out using nanoscale secondary-ion mass spectrometry. The results show that the δ34S values of the sulphide minerals range from +16.1‰ to +23.0‰, higher than that of marine sulphates hosted in Permian carbonate rocks (+11‰), but similar to that of sulphates over a broader area (+12.9‰ to +25.9‰). The sulphates in the regional rocks could therefore represent an important source of S for the Fule deposit via thermochemical sulphate reduction. The S source of the Fule deposit is different from those of most other Pb–Zn deposits in the SYG Pb–Zn mineralization province, which were mainly derived from the ore-bearing strata. The δ34S values of the early to late generations and some single sulphide crystals from the cores to rims show a slight increasing trend, implying that partial Rayleigh fractionation took place in the Fule deposit. It is suggested that the Fule sulphide precipitation resulted from the mixing of a metalliferous fluid with a H2S-rich fluid derived from the regional strata. Combining the geology, mineralogy and S isotope results with previous Pb isotope studies, it is suggested that the Fule deposit should be attributed to a Mississippi Valley type deposit.