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Sugarcane brown rust, caused by Puccinia melanocephala, is one of the main diseases of sugarcane in China. The identification and discovery of new resistance genes have important theoretical and practical significance for preventing outbreaks of brown rust and ensuring the sustainable production of sugarcane. To screen for polymorphic simple-sequence repeat (SSR) molecular markers for localization of brown rust resistance genes, we used two populations that are suitable for genetic linkage map construction and mapping of new resistance genes to construct resistant and susceptible genetic pools. We then screened 449 pairs of primers to identify polymorphic SSR markers in the parental lines and the resistant/susceptible genetic pools. The results showed that 25 pairs of primers directed amplification of polymorphic DNA fragments between the parents of the cross combination ‘Yuetang 03-393’ × ‘ROC 24’, and 16 pairs of primers amplified polymorphic fragments between the parents of the cross combination ‘Liucheng 03-1137’ × ‘Dezhe 93-88’. Four pairs of primers (SMC236CG, SCESSR0928, SCESSR0636 and SCESSR2551) amplified polymorphic DNA fragments between the parental lines and the resistant/susceptible genetic pools in ‘Yuetang 03-393’ × ‘ROC 24’. The results of this study will establish a solid foundation for the mapping of new brown rust resistance genes, genetic linkage map construction and the development of closely-associated molecular markers in sugarcane.
Mesanophrys sp. is a newly identified parasitic ciliate infecting farmed swimming crab. To demonstrate the correlation between parasite development and environmental conditions, this study aimed to investigate the effect of temperature, salinity, pH and frequency of passage of parasite on survival, growth and body size of Mesanophrys sp. in vitro. The results revealed that survival, population density and growth rate of the parasite were highest at 12°C and decreased with increasing temperature from 16 to 26°C. In addition, the survival, population density and growth rate of Mesanophrys sp. were high at 20‰. When salinity was adjusted to levels lower (0–10‰) and higher (40–60‰) than 20‰, the parasite's survival and growth rate gradually declined. The optimal pH for parasite survival was 8.0, whereas its survival was inhibited at <4.5 or >9.5. Our result also showed that parasite body proportions (length:width) were significantly smaller at the highest temperature compared to the lower temperature, whereas different salinities had no significant effect. Furthermore, we introduced dynamic parasite culture systems in vitro where Mesanophrys sp. was cultured in medium-containing culture plates through continually reducing and halving the old medium into fresh. Application of this optimized dilution timing technique with fresh medium and sub-cultured enabled a continuous culture of parasites. Under this optimized condition, the highest population density and exponential growth rate of the parasite were achieved than that of a control group. This study will help to understand the ciliated parasite infection dynamics and provides new possibilities for in vitro parasite-associated studies.
No studies have reported on how to relieve distress or relax in medical health workers while wearing medical protective equipment in coronavirus disease 2019 (COVID-19) pandemic. The study aimed to establish which relaxation technique, among six, is the most feasible in first-line medical health workers wearing medical protective equipment.
This was a two-step study collecting data with online surveys. Step 1: 15 first-line medical health workers were trained to use six different relaxation techniques and reported the two most feasible techniques while wearing medical protective equipment. Step 2: the most two feasible relaxation techniques revealed by step 1 were quantitatively tested in a sample of 65 medical health workers in terms of efficacy, no space limitation, no time limitation, no body position requirement, no environment limitation to be done, easiness to learn, simplicity, convenience, practicality, and acceptance.
Kegel exercise and autogenic relaxation were the most feasible techniques according to step 1. In step 2, Kegel exercise outperformed autogenic relaxation on all the 10 dimensions among the 65 participants while wearing medical protective equipment (efficacy: 24 v. 15, no space limitation: 30 v. 4, no time limitation: 31 v. 4, no body position requirement: 26 v. 4, no environment limitation: 30 v. 11, easiness to learn: 28 v. 5, simplicity: 29 v. 7, convenience: 29 v. 4, practicality: 30 v. 14, acceptance: 32 v. 6).
Kegel exercise seems a promising self-relaxation technique for first-line medical health workers while wearing medical protective equipment among COVID-19 pandemic.
Se, an essential biological trace element, is required for fish growth. However, the underlying mechanisms remain unclear. Protein deposition in muscle is an important determinant for fish growth. This study was conducted on juvenile rainbow trout (Oncorhynchus mykiss) to explore the nutritional effects of Se on protein deposition in fish muscle by analysing the postprandial dynamics of both protein synthesis and protein degradation. Trout were fed a basal diet supplemented with or without 4 mg/kg Se (as Se yeast), which has been previously demonstrated as the optimal supplemental level for rainbow trout growth. After 6 weeks of feeding, dietary Se supplementation exerted no influence on fish feed intake, whereas it increased fish growth rate, feed efficiency, protein retention rate and muscle protein content. Results of postprandial dynamics (within 24 h after feeding) of protein synthesis and degradation in trout muscle showed that dietary Se supplementation led to a persistently hyperactivated target of rapamycin complex 1 pathway and the suppressive expression of numerous genes related to the ubiquitin–proteasome system and the autophagy–lysosome system after the feeding. However, the ubiquitinated proteins and microtubule-associated light chain 3B (LC3)-II:LC3-I ratio, biomarkers for ubiquitination and autophagy activities, respectively, exhibited no significant differences among the fish fed different experimental diets throughout the whole postprandial period. Overall, this study demonstrated a promoting effect of nutritional level of dietary Se on protein deposition in fish muscle by accelerating postprandial protein synthesis. These results provide important insights about the regulatory role of dietary Se in fish growth.
A suite of Jurassic–Cretaceous migmatites was newly identified in the Liaodong Peninsula of the eastern North China Craton (NCC). Anatexis is commonly associated with crustal thickening. However, the newly identified migmatites were formed during strong lithospheric thinning accompanied by voluminous magmatism and intense deformation. Field investigations show that the migmatites are spatially associated with low-angle detachment faults. Numerous leucosomes occur either as isolated lenses or thin layers (dykes), parallel to or cross-cutting the foliation. Peritectic minerals such as titanite and sillimanite are distributed mainly along the boundaries of reactant minerals or are accumulated along the foliation. Most zircons show distinct core–rim structures, and the rims have low Th/U ratios (0.01–0.24). Zircon U–Pb dating results indicate that the protoliths of the migmatites were either the Late Triassic (224–221 Ma) diorites or metasedimentary rocks deposited sometime after c. 1857 Ma. The zircon overgrowth rims record crystallization ages of 173–161 Ma and 125 Ma, which represent the formation time of leucosomes. These ages are consistent with those reported magmatic events in the Liaodong Peninsula and surrounding areas. The leucosomes indicate a strong anatectic event during the Jurassic–Cretaceous period. Partial melting occurred through the breakdown of muscovite and biotite with the presence of water-rich fluid under a thermal anomaly regime. The possible mechanism that caused the 173–161 Ma and 125 Ma anatectic events was intimately related to the regional crustal extension during the lithospheric thinning of the NCC. Meanwhile, the newly generated melts further weakened the rigidity of the crust and enhanced the extension.
The core toroidal plasma intrinsic rotation has been studied by experiments and simulations in the Joint Texas Experimental Tokamak (J-TEXT). The direction of core intrinsic rotation in the J-TEXT plasma is counter-current. As the plasma density ramps up, the rotation velocity increases in the counter-current direction. By comparing four different electron densities, linear local gyrokinetic simulations have been performed by the Gyrokinetic Electromagnetic Numerical Experiment code for the first time on J-TEXT. It is found that the most dominant turbulence is the ion temperature gradient at
is the minor radius of the plasma and this is unchanged during the plasma density ramp up. By scanning the radial wave vectors, it is found that the residual stress term reverses from negative to positive when the plasma density exceeds a certain threshold. The pinch term is larger than the residual stress term at all four electron densities, which means that the pinch term is always dominant in the core of a J-TEXT plasma.
Topological quantum materials are a class of compounds featuring electronic band structures, which are topologically distinct from common metals and insulators. These materials have emerged as exceptionally fertile ground for materials science research. The topologically nontrivial electronic structures of these materials support many interesting properties, ranging from the topologically protected states, manifesting as high mobility and spin-momentum locking, to various quantum Hall effects, axionic physics, and Majorana modes. In this article, we describe different topological matters, including topological insulators, Weyl semimetals, twisted graphene, and related two-dimensional Chern magnetic insulators, as well as their heterostructures. We focus on recent materials discoveries and experimental advancements of topological materials, and their heterostructures. Finally, we conclude with prospects for the discovery of additional topological materials for studying quantum processes, quasiparticles and their composites, as well as exploiting potential applications of these materials.
To develop an equation that can estimate the 24-h urinary Na excretion by using casual spot urine specimen for older hypertensive participants in rural Ningxia and further to compare with the INTERSALT method, Kawasaki method and Tanaka method.
Older hypertensive participants in rural Ningxia provided their casual spot urine samples and 24-h urine samples between January 2015 and February 2017. Sex-specific equation was developed using linear forward stepwise regression analysis. Model fit was assessed using adjusted R2. Approximately half of all participants were randomly selected to validate the equation. Mean differences, intraclass correlation coefficients and Bland–Altman plots were used to evaluate the performance of all methods.
Pingluo County and Qingtongxia County in Ningxia Hui Autonomous Region, China.
Older hypertensive participants in rural Ningxia.
Totally, 807 of 1120 invited participants provided qualified 24-h urine samples and spot urine samples. There was no statistical difference comparing the laboratory-based method against the new method and the INTERSALT method, while Kawasaki method had the largest bias with a mean difference of 40·81 g/d (95 % CI 39·27, 42·35 g/d). Bland–Altman plots showed similar pattern of the results.
The INTERSALT method and the new equation have the potential to estimate the 24-h urinary Na excretion in this study population. However, the extrapolation of the results to other population needs to be careful. Future research is required to establish a more reliable method to estimate 24-h urinary Na excretion.
The potential pattern of regional cerebral blood flow (rCBF) in major depressive disorder (MDD) underlies different response to antidepressants medication remain unclear. This study aimed to investigate the differences of rCBF between patients with different treatment response.
Eighty MDD patients [(44 treatment-responsive depression (RD) and 36 non-responding depression (NRD)] and 42 healthy controls (HC) underwent pulsed arterial spin labeling (PASL) scans in magnetic resonance imaging and clinical estimates. The exact rCBF values of each groups were obtained via quantification evaluation.
Compared to NRD, the RD patients showed decreased rCBF values in frontal sensorimotor network (i.e. left paracentral lobule, left medial frontal gyrus, right superior frontal gyrus and right middle frontal gyrus), and further receiver operating curve (ROC) analyses demonstrated that the altered rCBF in these four regions exhibited outstanding performance on distinguishing NRD from RD. The NRD also exhibited reduced rCBF in bilateral cerebellum posterior lobe and right middle occipital gyrus and elevated rCBF in right postcentral gyrus and right middle frontal gyrus as compared to HC.
The decreased rCBF in frontal sensorimotor network appeared to be distinct characteristics for NRD, and might be severed as promising neuroimaging markers to differentiate depressed patients with weak early response to antidepressant medication. These findings expand our understanding of neural substrate underlying the antidepressant efficacy.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
In this research, a novel titanium metallic composite, Ti6Al4V powder mixed with 5 at.% Nb powder, was fabricated by selective laser melting (SLM). The effect of Nb addition on their phase transformation, microstructure evolution, mechanical properties, and corrosion behavior were studied. Interestingly, the novel alloy shows a combination of superior plastic deformation (εp= 18.9 ± 1.8%) and high compressive strength (σc= 1593 ± 38 MPa), which is 60.2 and 3.2% higher than that of the SLM-processed Ti6Al4V alloy under optimum printing parameters, respectively. However, the yield strength of Ti6Al4V + 5Nb (973 ± 45 MPa) is lower than that of the Ti6Al4V alloy (1066 ± 12 MPa). The solidification mechanism changes from planar to cellular mode with Nb addition. The ultrafine microstructure β grains are observed, which show a columnar shape and cellular shape. More importantly, the volume fraction of the β phase is significantly increased from 3.7% to 20.4% because of the Nb addition. In addition, the Ti6Al4V + 5Nb alloy possesses better corrosion resistance than the Ti6Al4V alloy. The research highlights that the addition of Nb powder in Ti6Al4V processed by SLM can improve the mechanical properties and corrosion resistance of the material.
Transient energy supply remains one of the key challenges limiting the development of transient implantable medical devices for monitoring, diagnosis, and treatment of diseases within a predetermined time frame. A key feature of such devices is their controllable degradation during service life. An on-board transient energy supply with predictable performance over time is required to drive transient electronics. In this article, we present recent advances in the development of materials for biodegradable energy-storage devices (batteries and supercapacitors) and biodegradable energy-harvesting systems (enzymatic biofuel cells and triboelectric nanogenerators). Future perspectives, challenges, and opportunities related to energy materials for transient power sources will also be summarized.
The small intestine is an important digestive organ and plays a vital role in the life of a pig. We tested the hypothesis that the length of the small intestine is related to growth performance and intestinal functions of piglets. A total of 60 piglets (Duroc × Landrace × Yorkshire), weaned at day 21, were fed an identical diet during a 28-day trial. At the end of the study, all piglets were sacrificed, dissected and grouped according to small intestine lengths (SILs), either short small intestine (SSI), middle small intestine (MSI) or long small intestine (LSI), respectively. Positive relationships between SIL and BW, average daily gain (ADG), average daily feed intake (ADFI) and gain-to-feed ratios (G : F) were observed. Final BW, ADG, ADFI and G : F significantly increased (P < 0.05) in MSI and LSI piglets compared with SSI piglets. Short small intestine and MSI had greater jejunal mucosa sucrase and alkaline phosphatase activities (P < 0.05) than LSI piglets. The mRNA level of solute carrier family 2 member 2 (Slc2a2) in the jejunal mucosa of SSI piglets was the greatest. The MSI piglets had a greater (P < 0.05) ileal villus height than other piglets and greater (P < 0.05) villus height-to-crypt depth ratios than LSI piglets. However, the LSI piglets had a greater (P < 0.05) ileal crypt depth than SSI piglets. No significant differences in duodenal, jejunal, caecal and colonic morphologies were detected among the groups. Moreover, luminal acetate, propionate, butyrate and total short-chain fatty acid contents were greater (P < 0.05) in SSI and MSI piglets than those in LSI piglets. In addition, there was greater serum glucose concentration in MSI piglets than other piglets. Serum albumin concentration in SSI piglets was the lowest. In conclusion, these results indicate that SIL was significantly positively associated with growth performance, and in terms of intestinal morphology and mucosal digestive enzyme activity, the piglets with a medium length of small intestine have better digestion and absorption properties.
Small intestinal epithelium homeostasis involves four principal cell types: enterocytes, goblet, enteroendocrine and Paneth cells. Epidermal growth factor (EGF) has been shown to affect enterocyte differentiation. This study determined the effect of dietary EGF on goblet, enteroendocrine and Paneth cell differentiation in piglet small intestine and potential mechanisms. Forty-two weaned piglets were used in a 2 × 3 factorial design; the major factors were time post-weaning (days 7 and 14) and dietary treatment (0, 200 or 400 µg/kg EGF supplementation). The numbers of goblet and enteroendocrine cells were generally greater with the increase in time post-weaning. Moreover, the supplementation of 200 µg/kg EGF increased (P < 0.01) the number of goblet and enteroendocrine cells in villus and crypt of the piglet small intestine as compared with the control. Dietary supplementation with 200 µg/kg EGF enhanced (P < 0.05) abundances of differentiation-related genes atonal homologue 1, mucin 2 and intestinal trefoil factor 3 messenger RNA (mRNA) as compared with the control. Piglets fed 200 or 400 µg/kg EGF diet had increased (P < 0.05) abundances of growth factor-independent 1, SAM pointed domain containing ETS transcription factor and pancreatic and duodenal homeobox 1 mRNA, but decreased the abundance (P < 0.01) of E74 like ETS transcription factor 3 mRNA as compared with the control. Animals receiving 400 µg/kg EGF diets had enhanced (P < 0.05) abundances of neurogenin3 and SRY-box containing gene 9 mRNA as compared with the control. The mRNA abundance and protein expression of lysozyme, a marker of Paneth cell, were also increased (P < 0.05) in those animals. As compared with the control, dietary supplementation with 200 µg/kg EGF increased the abundance of EGF receptor mRNA and the ratio of non-phospho(p)-β-catenin/β-catenin (P < 0.05) in villus epithelial cells at days 7 and 14. This ratio in crypt epithelial cells was higher (P < 0.05) on the both 200 and 400 µg/kg EGF groups during the same period. Our results demonstrated that dietary EGF stimulated goblet, enteroendocrine and Paneth cell differentiation in piglets during the post-weaning period, partly through EGFR and Wnt/β-catenin signalling.
Excessive intake of high-energy diets is an important cause of most obesity. The intervention of rats with high-fat diet can replicate the ideal animal model for studying the occurrence of human nutritional obesity. Proteomics and bioinformatics analyses can help us to systematically and comprehensively study the effect of high-fat diet on rat liver. In the present study, 4056 proteins were identified in rat liver by using tandem mass tag. A total of 198 proteins were significantly changed, of which 103 were significantly up-regulated and ninety-five were significantly down-regulated. These significant differentially expressed proteins are primarily involved in lipid metabolism and glucose metabolism processes. The intake of a high-fat diet forces the body to maintain physiological balance by regulating these key protein spots to inhibit fatty acid synthesis, promote fatty acid oxidation and accelerate fatty acid degradation. The present study enriches our understanding of metabolic disorders induced by high-fat diets at the protein level.
The present study was performed on antigen-presenting cells (APCs) of Theileria annulata transformed dendritic cells (TaDCs) and monocyte-derived dendritic cells (MoDCs) to compare differences in antigen presentation and stimulation of T lymphocyte proliferation. Antigen presentation for T lymphocyte proliferation was analysed by flow cytometry. Additionally, the level of mRNA transcription of small GTPases of the Rab family expressed in the TaDC cell line was analysed by quantitative real-time polymerase chain reaction (Q-RT-PCR). The endocytosis rate of TaDCs was significantly (P < 0.01) lower than in MoDCs. In contrast, when T lymphocytes were co-cultured with TaDC-APCs T cell proliferation was similar, while co-culture with MoDC-APC stimulated proliferation of CD4+ cells to a greater degree than CD8+ cells. However, the efficacy of TaDC-APCs to stimulate T lymphocytes dropped as the number of passages of TaDC-APC increased. Likewise, the transcription level of Rab family genes also significantly (P > 0.001) declined with progressive passages (>50) of the TaDC cell line. We conclude that initially the TaDC cell line efficiently presents antigen to stimulate T lymphocyte proliferation to produce a cellular immune response against the presented antigen.
The gut is composed of a single layer of intestinal epithelial cells and plays important roles in the digestion and absorption of nutrients, immune and barrier functions and amino acid metabolism. Weaning stress impairs piglet intestinal epithelium structural and functional integrities, which results in reduced feed intake, growth rates and increased morbidity and mortality. Several measures are needed to maintain swine gut development and growth performance after weaning stress. A large body of evidence indicates that, in weaning piglets, glutamine, a functional amino acid, may improve growth performance and intestinal morphology, reduce oxidative damage, stimulate enterocyte proliferation, modulate cell survival and death and enhance intestinal paracellular permeability. This review focuses on the effects of glutamine on intestinal health in piglets. The aim is to provide evidentiary support for using glutamine as a feed additive to alleviate weaning stress.