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This study was a retrospective multicentre cohort study of patients with coronavirus disease 2019 (COVID-19) diagnosed at 24 hospitals in Jiangsu province, China as of 15 March 2020. The primary outcome was the occurrence of acute respiratory failure during hospital stay. Of 625 patients, 56 (9%) had respiratory failure. Some selected demographic, epidemiologic, clinical and laboratory features as well as radiologic features at admission and treatment during hospitalisation were significantly different in patients with and without respiratory failure. The multivariate logistic analysis indicated that age (in years) (odds ratio [OR], 1.07; 95% confidence interval [CI]: 1.03–1.10; P = 0.0002), respiratory rate (breaths/minute) (OR, 1.23; 95% CI: 1.08–1.40; P = 0.0020), lymphocyte count (109/l) (OR, 0.18; 95% CI: 0.05–0.69; P = 0.0157) and pulmonary opacity score (per 5%) (OR, 1.38; 95% CI: 1.19–1.61; P < 0.0001) at admission were associated with the occurrence of respiratory failure. Older age, increased respiratory rate, decreased lymphocyte count and greater pulmonary opacity score at admission were independent risk factors of respiratory failure in patients with COVID-19. Patients having these risk factors need to be intensively managed during hospitalisation.
Lifestyle interventions are an important and viable approach for preventing cognitive deficits. However, the results of studies on alcohol, coffee and tea consumption in relation to cognitive decline have been divergent, likely due to confounds from dose–response effects. This meta-analysis aimed to find the dose–response relationship between alcohol, coffee or tea consumption and cognitive deficits.
Prospective cohort studies or nested case-control studies in a cohort investigating the risk factors of cognitive deficits were searched in PubMed, Embase, the Cochrane and Web of Science up to 4th June 2020. Two authors searched the databases and extracted the data independently. We also assessed the quality of the studies with the Newcastle-Ottawa scale. Stata 15.0 software was used to perform model estimation and plot the linear or nonlinear dose–response relationship graphs.
The search identified 29 prospective studies from America, Japan, China and some European countries. The dose–response relationships showed that compared to non-drinkers, low consumption (<11 g/day) of alcohol could reduce the risk of cognitive deficits or only dementias, but there was no significant effect of heavier drinking (>11 g/day). Low consumption of coffee reduced the risk of any cognitive deficit (<2.8 cups/day) or dementia (<2.3 cups/day). Green tea consumption was a significant protective factor for cognitive health (relative risk, 0.94; 95% confidence intervals, 0.92–0.97), with one cup of tea per day brings a 6% reduction in risk of cognitive deficits.
Light consumption of alcohol (<11 g/day) and coffee (<2.8 cups/day) was associated with reduced risk of cognitive deficits. Cognitive benefits of green tea consumption increased with the daily consumption.
Increasing evidence indicates that major depressive disorder (MDD) is associated with cognitive as well as mood disturbances.
To evaluate cognitive function and white matter structure, resting-state brain function in first-episode, treatmentnaive patients with MDD.
To explore brain structure and function mechanisms of cognitive impairment in MDD.
46 Han Chinese MDD patients aged 18–45 year and 46 controls were assessed by a series of validated test procedures.Then, 30 patients and 30 controls were obtained by MRI scan.White matter abnormalities evaluated using diffusion tensor imaging (DTI) were analyzed using tract based spatial statistics (TBSS) and resting-state brain function was evaluated using regional homogeneity (ReHo) analysis.
Cognitive impairment in patients with MDD was demonstrated by reduced accuracy in the Wisconsin Card Sorting test (WSCT) and to a lesser extent the Continuous Performance test (CPT) and Trail Making tests (TMT). White matter abnormalities found in the left cerebellum, and resting-state abnormalities present in the left inferior parietal gyrus, left anterior cingulate nucleus and left hippocampal gyrus were associated with impaired performance in the WSCT and CPT tests. We also showed that poor WSCT performance was associated with increased interconnectivity between the left ventral anterior cingulate nucleus and the medial frontal lobe areas.
The present study indicates cognitive disturbances in patients with MDD are associated with white matter and resting-state changes and altered interconnections in specific brain areas.
The association between gray matter and cognitive dysfunction in young major depression remains unclear.
To investigate the brain gray matter and the correlation with cognitive function in first-episode, treatment-naive patients with major depressive disorder (MDD).
To explore brain structural pathological mechanisms of cognitive impairment in MDD.
46 MDD aged 18-45 year and 46 controls were assessed by Wisconsin Card Sorting Test (WCST) and Trail making test (TMT). Then, 30 patients and 30 controls were obtained by MRI scan.
The total number of errors, number of preservative errors, random errors of WSCT in MDD were significantly more than that in controls, and the completion time in the TMT-A and TMT-B was longer than that in controls. MDD showed significant less gray matter volumns than controls in frontal lobe (right precentral gyrus, bilateral superior frontal gyrus and right middle frontal gyrus), parietal lobe (left postcentral gyrus, left paracentral lobule, and bilateral precuneus), temporal lobe (right superior temporal gyrus), and occipital lobe (left superior occipital gyrus). There was a significant negative correlation between left postcentral gyrus and left superior occipital gyrus gray matter density and the TMT-B completion time (r=-0.462, P=0.017; r=-0.448, P=0.022).
The first-episode MDD patient exhibiteded cognitive impairment and showed significant lower gray matter density than controls in frontal lobe, parietal lobe, temporal lobe, occipital lobe. Decreased gray matter density in left postcentral gyrus and left superior occipital gyrus may be involved in the executive dysfunction.
This study aimed at comparing the factors associated with the natural progression between typical progressors (TPs) and rapid progressors (RPs) in HIV-infected individuals. A retrospective study was conducted on 2095 eligible HIV-infected individuals from 1995 to 2016 in a high-risk area of Henan Province, China. Propensity score matching was used to balance covariates, and the conditional logistic regression analyses were performed to explore the factors of natural disease progression among HIV infectors. A total of 379 pairs of RPs and TPs were matched. The standardised difference values of all covariates were less than 10%. HIV-infected individuals transmitted through sexual transmission (odds ratio (OR) 0.56, 95% confidence interval (CI) 0.36–0.85) were more likely to progress to AIDS compared with those infected through contaminated blood. Older age at diagnosis of HIV-infected individuals (OR 0.72, 95% CI 0.58–0.89) exhibited a faster progression to AIDS. HIV-infected individuals identified through a unique survey (OR 7.01, 95% CI 2.99–16.44) were less likely to progress to AIDS compared with those identified through medical institutions. HIV-infected individuals who had higher baseline CD4+T cell counts (OR 3.37, 95% CI 2.59–4.38) had a slower progression to AIDS. These findings provide evidence for natural disease progression from HIV to AIDS between TPs and RPs.
Tuberculosis (TB) is the leading cause of death among infectious diseases. China has a high burden of TB and accounted for almost 13% of the world's cases of multi-drug resistant (MDR) TB. Spinal TB is one reason for the resurgence of TB in China. Few large case studies of MDR spinal TB in China have been conducted. The aim of this research was to observe the epidemiological characteristics of inpatients with MDR spinal TB in six provinces and cities of China from 1999–2015. This is a multicentre retrospective observational study. Patients' information was collected from the control disease centre and infectious disease database of hospitals in six provinces and cities in China. A total of 3137 patients with spinal TB and 272 patients with MDR spinal TB were analysed. The result showed that MDR spinal TB remains a public health concern and commonly affects patients 15–30 years of age (34.19%). The most common lesions involved the thoracolumbar spine (35.66%). Local pain was the most common symptom (98.53%). Logistic analysis showed that for spinal TB patients, reside in rural district (OR 1.79), advanced in years (OR 1.92) and high education degree (OR 2.22) were independent risk factors for the development of MDR spinal TB. Women were associated with a lower risk of MDR spinal TB (OR 0.48). The most common first-line and second-line resistant drug was isoniazid (68.75%) and levofloxacin (29.04%), respectively. The use of molecular diagnosis resulted in noteworthy clinical advances, including earlier initiation of MDR spinal TB treatment, improved infection control and better clinical outcome. Chemotherapy and surgery can yield satisfactory outcomes with timely diagnosis and long-term treatment. These results enable a better understanding of the MDR spinal TB in China among the general public.
Chinese men who have sex with men (MSM) are at high risk for depression, anxiety and suicide. The estimated prevalence of these problems is essential to guide public health policy, but published results vary. This meta-analysis aimed to estimate the prevalence of depressive symptoms, anxiety symptoms and suicide among Chinese MSM.
Systematic searches of EMBASE, MEDLINE, PsycINFO, PubMed, CNKI and Wanfang databases with languages restricted to Chinese and English for studies published before 10 September 2019 on the prevalence of depressive symptoms, anxiety symptoms, suicidal ideation, suicide plans and suicide attempts among Chinese MSM. Studies that were published in the peer-reviewed journals and used validated instruments to assess depression and anxiety were included. The characteristics of studies and the prevalence of depression and anxiety symptoms, suicidal ideation, suicide plans and suicide attempts were independently extracted by authors. Random-effects modelling was used to estimate the pooled rates. Subgroup analysis and univariate meta-regression were conducted to explore potential sources of heterogeneity. This study followed the PRISMA and MOOSE.
Sixty-seven studies were included. Fifty-two studies reported the prevalence of depressive symptoms, with a combined sample of 37 376 people, of whom 12 887 [43.2%; 95% confidence interval (CI), 38.9–47.5] reported depressive symptoms. Twenty-seven studies reported the prevalence of anxiety symptoms, with a combined sample of 10 531 people, of whom 3187 (32.2%; 95% CI, 28.3–36.6) reported anxiety symptoms. Twenty-three studies reported the prevalence of suicidal ideation, with a combined sample of 15 034 people, of whom 3416 (21.2%; 95% CI, 18.3–24.5) had suicidal ideation. Nine studies reported the prevalence of suicide plans, with a combined sample of 5271 people, of whom 401 (6.2%; 95% CI, 3.9–8.6) had suicide plans. Finally, 19 studies reported the prevalence of suicide attempts, with a combined sample of 27 936 people, of whom 1829 (7.3%; 95% CI, 5.6–9.0) had attempted suicide.
The mental health of Chinese MSM is poor compared with the general population. Efforts are warranted to develop interventions to prevent and alleviate mental health problems among this vulnerable population.
In this study, the thermal deformation of a machine tool structure due to the heat generated during operation was analyzed, and embedded cooling channels were applied to exchange the heat generated during the operation to achieve thermal error suppression. Then, the finite volume method was used to simulate the effect of cooling oil temperature on thermal deformation, and the effect of thermal suppression was experimentally studied using a feed system combined with a cooler to improve the positioning accuracy of the machine tool. In this study, the supply oil temperature in the structural cooling channels was found to significantly affect the position accuracy of the moving table and moving carrier. If the supply oil temperature in the cooling channels is consistent with the operational ambient temperature, the position accuracy of the moving table in the Y direction and the moving carrier in the X and Z directions has the best performance under different feed rates. From the thermal suppression experiments of the embedded cooling channels, the positioning accuracy of the feed system can be improved by approximately 25.5 % during the dynamic feeding process. Furthermore, when the hydrostatic guideway is cooled and dynamic feeding is conducted, positioning accuracy can be improved by up to 47.8 %. The machining accuracy can be improved by approximately 60 % on average by using the embedded cooling channels in this study. Therefore, thermal suppression by the cooling channels in this study can not only effectively improve the positioning accuracy but also enhance machining accuracy, proving that the method is effective for enhancing machine tool accuracy.
Rumen-protected betaine (RPB) can enhance betaine absorption in the small intestine of ruminants, while betaine can alter fat distribution and has the potential to affect the meat quality of livestock. Hence, we hypothesized that RPB might also affect the meat quality of lambs. Sixty male Hu sheep of similar weight (30.47 ± 2.04 kg) were selected and randomly subjected to five different treatments. The sheep were fed a control diet (control treatment, CTL); 1.1 g/day unprotected-betaine supplemented diet (UPB); or doses of 1.1 g/day (low RPB treatment; L-PB), 2.2 g/day (middle RPB treatment; M-PB) or 3.3 g/day (high RPB treatment; H-PB) RPB-supplemented diet for 70 days. Slaughter performance, meat quality, fatty acid and amino acid content in the longissimus dorsi (LD) muscle, shoulder muscle (SM) and gluteus muscle (GM) were measured. Compared with CTL, betaine (including UPB and RPB) supplementation increased the average daily weight gain (ADG) (P < 0.05) and average daily feed intake (P < 0.01) of lambs. Rumen-protected betaine increased ADG (P < 0.05) compared with UPB. With increasing RPB doses, the eye muscle area of the lambs linearly increased (P < 0.05). Compared with CTL, betaine supplementation decreased water loss (P < 0.05) in SM and increased pH24 in the SM (P < 0.05) and GM (P < 0.05). Compared with UPB, RPB decreased water loss in the GM (P < 0.01), decreased shear force (P < 0.05) in the LD and SM and increased the pH of the meat 24 h after slaughter (pH24). With increasing RPB doses, the shear force and b* value in the LD linearly decreased (P < 0.05), and the pH24 of the meat quadratically increased (P < 0.05). Compared with CTL, betaine supplementation increased the polyunsaturated fatty acid in the GM (P < 0.05). Compared with UPB, RPB supplementation decreased the saturated fatty acid (SFA) content in the LD (P < 0.05) and increased the unsaturated fatty acids (UFA), mono-unsaturated fatty acids and UFA/SFA ratio in the LD (P < 0.05). Compared with CTL, the content of histidine in the LD increased with betaine supplementation. Compared with UPB, RPB supplementation increased the content of total free amino acids and flavor amino acids in the LD of lambs (P < 0.05). With increasing RPB, the isoleucine and phenylalanine contents in the LD linearly increased (P < 0.05). Overall, the data collected indicated that the meat quality of lambs (especially in the LD) improved as a result of betaine supplementation, and RPB showed better effects than those of UPB.
KRTAP8-1 was the initial high-glycine-tyrosine keratin-associated protein gene recognized in sheep, but little is known about the functional influence of this gene. The current study used polymerase chain reaction-single stranded conformational polymorphism analysis to genotype KRTAP8-1 in 391 Southdown × Merino-cross sheep from six sire-lines. Five previously described variants (named A to E) of KRTAP8-1 were identified with frequencies of 67.0, 14.2, 7.0, 10.7 and 1.0%, respectively. Of the four variants (A, B, C and D) that occurred at a frequency greater than 5%, the presence of C was found to be associated with a reduction in mean fibre curvature (MFC) and the presence of D was associated with an increase in mean staple strength (MSS), whereas the presence of A had a trend of association with reduced MSS. Associations were not identified with other wool traits. These results suggest that variation in KRTAP8-1 affects MSS and MFC, and that KRTAP8-1 has the potential to be used as a genetic marker for improving these traits.
Optimizing the dietary calcium (Ca) level is essential to maximize the eggshell quality, egg production and bone formation in poultry. This study aimed to establish the Ca requirements of egg-type duck breeders from 23 to 57 weeks of age on egg production, eggshell, incubation, tibial, plasma and ovary-related indices, as well as the expression of matrix protein-related genes. Totally, 450 Longyan duck breeders aged 21 weeks of age were allotted randomly into five treatments, each with six replicates of 15 individually caged birds. The data collection started from 23 weeks of age and continued over the following 35 weeks. The five groups corresponded to five dietary treatments containing either 2.8%, 3.2%, 3.6%, 4.0% or 4.4% Ca. The tested dietary Ca levels increased (linear, P <0.01) egg production and egg mass, and linearly improved (P <0.01) the feed conversion ratio (FCR). Increasing the dietary Ca levels from 2.8% to 4.4% increased (P <0.01) the eggshell thickness and eggshell content. The tested Ca levels showed a quadratic effect on eggshell thickness and ovarian weight (P <0.01); the highest values were obtained with the Ca levels 4.0% and 3.6%, respectively. Dietary Ca levels affected the small yellow follicles (SYF) number and SYF weight/ovarian weight, and the linear response (P <0.01) was significant vis-à-vis SYF number. In addition, dietary Ca levels increased (P <0.05) the tibial dry weight, breaking strength, mineral density and ash content. Plasma and tibial phosphorus concentration exhibited a quadratic (P <0.01) response to dietary Ca levels. Plasma calcitonin concentration linearly (P <0.01) increased as dietary Ca levels increased. The relative expression of carbonic anhydrase 2 in the uterus rose (P <0.01) with the increment of dietary Ca levels, and the highest value was obtained with 3.2% Ca. In conclusion, Longyan duck breeders fed a diet with 4.0% Ca had superior eggshell and tibial quality, while those fed a diet with 3.6% Ca had the heaviest ovarian weights. The regression model indicated that the dietary Ca levels 3.86%, 3.48% and 4.00% are optimal levels to obtain maximum eggshell thickness, ovarian weight and tibial mineral density, respectively.
Co-receptor tropism has been identified to correlate with HIV-1 transmission and the disease progression in patients. A molecular epidemiology investigation of co-receptor tropism is important for clinical practice and effective control of HIV-1. In this study, we investigated the co-receptor tropism on HIV-1 variants of 85 antiretroviral-naive patients with Geno2pheno algorithm at a false-positive rate of 10%. Our data showed that a majority of the subjects harboured the CCR5-tropic virus (81.2%, 69/85). No significant differences in gender, age, baseline CD4+ T-cell counts and transmission routes were observed between subjects infected with CXCR4-tropic or CCR5-tropic virus. The co-receptor tropism appeared to be associated with the virus genotype; a significantly more CXCR4-use was predicted in CRF01_AE infections whereas all CRF07_BC and CRF08_BC were predicted to use CCR5 co-receptor. Sequences analysis of V3 revealed a higher median net charge in the CXCR4 viruses over CCR5 viruses (4.0 vs. 3.0, P < 0.05). The predicted N-linked glycosylation site between amino acids 6 and 8 in the V3 region was conserved in CCR5 viruses, but not in CXCR4 viruses. Besides, variable crown motifs were observed in both CCR5 and CXCR4 viruses, of which the most prevalent motif GPGQ existed in both viral tropism and almost all genotypes identified in this study except subtype B. These findings may offer important implications for clinical practice and enhance our understanding of HIV-1 biology.
Keratins are the main structural proteins of wool fibres, and it is thought that variation in the keratins may affect wool fibre characteristics. Polymerase chain reaction-single stranded conformational polymorphism (PCR-SSCP) analyses were used to investigate four regions of the ovine keratin gene KRT31 including a portion of the promoter, the exon 1, exon 3 and exon 7 regions. Initially, in a screening panel of 300 New Zealand Romney, Merino and White Dorper sheep obtained from 26 farms, three, two, two and two PCR-SSCP banding patterns were observed for these four regions, respectively. The promoter region, the exon 1 and exon 3 regions contained two single nucleotide polymorphisms (SNPs) and the exon 7 region contained one SNP. The effect of the variation found in the promoter region on wool traits was subsequently investigated in 485 Southdown × Merino-cross lambs from seven sire-lines. The three variants identified in the original 300 sheep (named A, B and C) were observed with frequencies of 56, 29 and 15%, respectively. The presence of A and B had no significant effect on wool traits, but the presence of C was found to be associated with an increase in greasy fleece weight (GFW), clean fleece weight (CFW) and mean staple length (MSL). There was an effect of genotype on CFW and MSL, with BC sheep producing wool of higher CFW and MSL than AA, AB, AC and BB sheep. These results suggest that ovine KRT31 might be a useful candidate gene for improving wool traits.
A new generation of high power laser facilities will provide laser pulses with extremely high powers of 10 petawatt (PW) and even 100 PW, capable of reaching intensities of
in the laser focus. These ultra-high intensities are nevertheless lower than the Schwinger intensity
at which the theory of quantum electrodynamics (QED) predicts that a large part of the energy of the laser photons will be transformed to hard Gamma-ray photons and even to matter, via electron–positron pair production. To enable the investigation of this physics at the intensities achievable with the next generation of high power laser facilities, an approach involving the interaction of two colliding PW laser pulses is being adopted. Theoretical simulations predict strong QED effects with colliding laser pulses of
focused to intensities
Dietary supplementation with the organic chromium (Cr) has been shown to positively affect the immune function of poultry. However, to our knowledge, no experiment has been done to directly compare the impacts of Cr chloride and chromium picolinate (CrPic) on the immune responses of broilers vaccinated with Avian Influenza (AI) virus vaccine. Therefore, the present experiment was conducted to investigate the effects of supplemental Cr sources (Cr chloride and CrPic) and levels on the growth performance and immune responses of broilers vaccinated with AI virus vaccine so as to provide an effective nutritional strategy for improving immune function of broilers. A total of 432 1-day (d)-old male broiler chicks were used in a 1 plus 2×4 design. Chickens were given either a diet without Cr supplementation (control) or diets supplemented with 0.4, 0.8, 1.6, or 3.2 mg Cr/kg as either Cr chloride or CrPic for 42 d. Compared to the control, dietary Cr supplementation had no effect (P>0.05) on average daily gain, average daily feed intake and gain : feed of broilers during the starter and grower phases, but increased (P<0.05) the relative weights of bursa of fabricius on d 21 and thymus, spleen, or bursa of fabricius on d 42, serum antibody titers against AI virus on d 21, 28, 35 and 42, blood T-lymphocyte transformation rate on d 28 and 42, blood T-lymphocyte percentage on d 42, and serum interleukin-2 contents on d 28. Broilers fed the diets supplemented with the inorganic Cr chloride had higher (P<0.05) weights of thymus, spleen and bursa of fabricius than those fed the diets supplemented with the CrPic on d 42. In addition, broilers fed the diets supplemented with the CrPic had higher (P<0.05) antibody titers against AI virus than those fed the diets supplemented with the inorganic Cr chloride on d 21 and 35. These results indicate that dietary Cr supplementation improved immune responses of broilers vaccinated with AI virus, and the inorganic Cr chloride was more effective than the CrPic in increasing the relative weights of lymphoid organs, however, the CrPic was more effective than the inorganic Cr chloride in enhancing the serum antibody titer against AI virus.
Keratin-associated proteins (KAPs) are constituents of wool and hair fibres and are believed to play an important role in determining the characteristics of the fibres. In the current study, a polymerase chain reaction-single stranded conformational polymorphism (PCR-SSCP) approach was used to screen for variation in the ovine KAP15-1 gene (KRTAP15-1). Four PCR-SSCP banding patterns, representing four different variants (named A to D), were detected. Four single nucleotide polymorphisms were found within the coding region and three of these were non-synonymous. The effect of this genetic variation on wool traits was investigated in 396 Merino × Southdown-cross sheep. Of the three variants found in these sheep (A, B and C), the presence of B was found to be associated with decreased wool yield, while C was associated with increased wool yield and decreased fibre diameter standard deviation. Sheep of genotype AC had a higher wool yield than those of genotype AA or AB.
Multiple human immunodeficiency virus (HIV)-1 genotypes in China were first discovered in Yunnan Province before disseminating throughout the country. As the HIV-1 epidemic continues to expand in Yunnan, genetic characteristics and transmitted drug resistance (TDR) should be further investigated among the recently infected population. Among 2828 HIV-positive samples newly reported in the first quarter of 2014, 347 were identified as recent infections with BED-captured enzyme immunoassay (CEIA). Of them, 291 were successfully genotyped and identified as circulating recombinant form (CRF)08_BC (47.4%), unique recombinant forms (URFs) (18.2%), CRF01_AE (15.8%), CRF07_BC (14.4%), subtype C (2.7%), CRF55_01B (0.7%), subtype B (0.3%) and CRF64_BC (0.3%). CRF08_BC and CRF01_AE were the predominant genotypes among heterosexual and homosexual infections, respectively. CRF08_BC, URFs, CRF01_AE and CRF07_BC expanded with higher prevalence in central and eastern Yunnan. The recent common ancestor of CRF01_AE, CRF07_BC and CRF08_BC dated back to 1983.1, 1992.1 and 1989.5, respectively. The effective population sizes (EPS) for CRF01_AE and CRF07_BC increased exponentially during 1991–1999 and 1994–1999, respectively. The EPS for CRF08_BC underwent two exponential growth phases in 1994–1998 and 2001–2002. Lastly, TDR-associated mutations were identified in 1.8% of individuals. These findings not only enhance our understanding of HIV-1 evolution in Yunnan but also have implications for vaccine design and patient management strategies.
Nitrogen (N) application and irrigation to winter wheat may decrease leaf temperature and enhance photosynthesis: as a result, more photosynthates will be allocated to the grains, resulting in higher grain yields. To investigate this hypothesis, a 2-year field study was conducted with three levels of N fertilizer application (no fertilizer, N0; 240 kg N/ha, N1; 360 kg N/ha, N2) and two different water regimes (rainfed with no irrigation, R; irrigation at the over-wintering, stem elongation and grain filling stages, W). The results show that both N application and supplemental irrigation significantly increased grain yield with increases in both grain number/m2 and the 1000-grain weight, viz., WN2>WN1>WN0>RN2>RN1>RN0. In addition, application of N under both water regimes significantly increased flag leaf area, above-ground biomass and single stem productivity and decreased leaf temperature, which led to an increase in net photosynthesis rates and ribulose bisphosphate (RuBP) carboxylase activity. Moreover, analysis of the chlorophyll α fluorescence transient showed that N fertilizer application and supplemental irrigation significantly increased electron donor and acceptor performance of the photosystem II reaction centre.