Linear and nonlinear thermoelectric transport in a quantum spin Hall insulators coupled with a nanomagnet.

Thermoelectric effects in quantum systems have been focused in recent years. Thermoelectric energy conversion study of systems with edge states, such as quantum Hall insulators and quantum spin Hall insulators, is one of the most important frontier topics in material science and condensed-matter physics. Based on the previous paper (Gresta in Phys Rev Lett 123:186801, 2019), we further investigated the linear and nonlinear thermoelectric transport properties of helical edge states of the quantum spin Hall insulators coupled with double nanomagnet, calculated the Seebeck coefficients [Formula: see text] and the thermoelectrical figure of merit ZT, discussed the influence of the length of the nanomagnet and the relative tilt angle of component of the magnetization perpendicular on the thermoelectric coefficients ([Formula: see text] and ZT), and summarized some meaningful conclusions in the linear response regime. In the nonlinear regime, we calculated the equivalent figure of merit [Formula: see text] and the power-generation efficiency [Formula: see text] in different length of the nanomagnet, obtain the temperature difference of achieving optimal thermoelectricity. The results of this paper further confirm that the setup can indeed be used as a device for achieving high performance thermoelectric.

Thermoelectric transport in two-terminal topological nodal-line semimetals nanowires.

Recently discovered topological nodal-line semimetals (TNLSMs) have received considerable research interest due to their rich physical properties and potential applications. TNLSMs have the particular band structure to lead to many novel properties. Here we theoretically study the thermoelectric transport of a two-terminal pristine TNLSM nanowires and TNLSMsp-n-pjunctions. The Seebeck coefficientsScand the thermoelectrical figure of meritZTare calculated based on the Landauer-Büttiker formula combined with the nonequilibrium Green's function method. In pristine TNLSM nanowires, we discuss the effect of the magnetic fieldsφ, the disorderD, the on-site energyµz, and the mass termmon the thermoelectric coefficient and find that the transport gap can lead to a largeScandZT. When transmission coefficient jumps from one integer plateau to another,ScandZTshow a series of peaks. The peaks ofScandZTare determined by the jump of the transmission coefficient plateau and are not associated with the plateau itself. For TNLSMsp-n-pjunctions,ScandZTstrongly depend on the parameterξof potential well. We can get a largeZTby adjusting the parameterξand magnetic fieldφ. In TNLSMsp-n-pjunctions,ZThas the large value and is easily regulated. This setup has promising application prospects as a thermoelectric device.

The adipokinetic hormone signaling system regulates the sensitivity of Bactrocera dorsalis to malathion.

The neuropeptide adipokinetic hormone (AKH) binds to the AKH receptor (AKHR) to regulate carbohydrate and lipid metabolism. It also participates in the insect anti-stress response. We used RT-qPCR to detect the expression levels of 39 neuropeptides in malathion-susceptible (MS) and malathion-resistant (MR) strains of Bactrocera dorsalis. AKH and AKHR were highly expressed in the MR strain. Using a malathion bioassay and RNA interference (RNAi), we demonstrated that AKHR is involved in the susceptibility of B. dorsalis to malathion. We found significantly reduced expression of two detoxification enzyme genes (glutathione-S-transferase, GST and α-esterase, CarE) after AKHR RNAi. Based on our previous data, GSTd10 and CarE6 participate the direct metabolism of malathion in this fly, which is also verified by a malathion metabolism assay by HPLC using the crude enzymes in the current study. These results suggest that AKHR plays an important role in affecting malathion susceptibility via detoxification enzyme genes.

The Transcription Factor MafB Regulates the Susceptibility of Bactrocera dorsalis to Abamectin via GSTz2.

Pesticide resistance is a serious problem that poses a major challenge to pest control. One of the most potent resistance mechanisms is the overexpression of genes coding for detoxification enzymes. The expression of detoxification genes is regulated by a series of transcription factors. Previous studies have revealed that the increased expression of detoxification genes contributes to the insecticide tolerance of Bactrocera dorsalis. Our objective was thus to identify the transcription factors involved in this process. Temporal expression profiles showed that the transcription factor MafB and detoxification genes were expressed highly in the fat body. Further analysis showed that the expression of MafB, GSTz2, and CYP473A3 was induced by abamectin. Disruption of the MafB transcription factor through RNA interference decreased the transcript levels of GSTz2 and CYP473A3 and increased the susceptibility to abamectin significantly. Direct silencing of the expression of GSTz2 also increased susceptibility to abamectin, while CYP473A3 did not. In conclusion, these results suggest that the expression of GSTz2 and CYP473A3 was regulated by the transcription factor MafB, and the up-regulation of GSTz2 via MafB decreased the susceptibility of B. dorsalis to abamectin.

Comparative transcriptome analysis reveals differentially expressed genes in the Asian citrus psyllid (Diaphorina citri) upon heat shock.

Temperature is an important factor influencing insect distribution. In the tropical and subtropical regions, insects always suffer the extreme temperature. Therefore, appropriate molecular response to temperature change is crucial for their survival. To understand how Diaphorina citri responds to high temperature at the molecular level, we conducted a comparative analysis of the transcriptomes of D. citri under room temperature and 40 °C heat shock treatment. The RNA sequencing analysis identified a total of 451 differentially expressed genes upon heat stress, including 167 down-regulated genes and 284 up-regulated genes. Thermal stress mainly significantly induced the transcription of molecular chaperone, protein biosynthesis and oxidation resistance, including members of the heat shock protein families, ATPases, and detoxifying enzymes. This study provides a preliminary insight into the transcriptional response of D. citri to heat stress and provides a foundation for the future functional validation of genes involved in thermotolerance in this important insect pest in tropical and subtropical regions.

Diversity of Bacterial Communities in the Intestinal Tracts of Two Geographically Distant Populations of Bactrocera dorsalis (Diptera: Tephritidae).

The oriental fruit fly, Bactrocera dorsalis (Hendel), is one of the most destructive agricultural pests and hosts diverse intestinal bacterial communities. We used 16S rRNA gene sequencing to investigate the microbial communities associated with the intestines of females and males from two B. dorsalis populations collected from Hainan and Guizhou Provinces of China. A total of 260,615 high-quality 16S rRNA gene reads with an average length of 253 bp were obtained. Highly diverse bacterial communities were observed across individuals, with communities containing between 691 and 1,262 bacterial operational taxonomic units. In addition, 37 bacterial phyla, 65 classes, 130 orders, 198 families, 201 genera, and 70 annotated species were identified, wherein the Proteobacteria were the most dominant phylum among all of the libraries, followed by the Firmicutes and Bacteroidetes. Bacterial community composition varied by host sex and geographic location of the populations. Female gut communities comprised fewer bacterial families than males, and females had lower relative abundances of 33 of the 35 most abundant families. In addition, female gut communities harbored greater abundances of Enterobacteriaceae than males. The Hainan population gut communities contained fewer bacterial families than those of the Guizhou populations. However, 5 of the 35 most abundant families were more abundant in communities from the Hainan population than those of the Guizhou population. The results of this study help us better understand the importance of symbiotic bacteria in B. dorsalis and provide a foundation for assessing the use of gut microorganisms as bio-control agents for these serious pests.

The protective role of Tongxinluo on blood-brain barrier after ischemia-reperfusion brain injury.

ETHNOPHARMACOLOGICAL RELEVANCE: Tongxinluo (TXL), a renowned traditional Chinese medicine, consists of several different kinds of ingredients and has been widely used to treat myocardial infarction and ischemic stroke. However, the underlying neuroprotective mechanisms are not fully understood. AIM OF THE STUDY: We focus on the effect of TXL on blood-brain barrier (BBB) including edema formation and tight junction (TJ) protein rearrangement, and inflammatory response after transient middle cerebral artery occlusion (tMCAO). We further explore the protective mechanism of TXL on ischemia-induced BBB damage. MATERIALS AND METHODS: Adult CD1 male mice (n=168) were randomly divided into TXL pre-treatment group, TXL pre-post treatment group, TXL post-treatment group, control group and sham group. Mice in TXL pre-treatment group were given TXL solution by 1g/kg/day orally for 7 days before tMCAO. Mice in pre-post treatment group were continuously given TXL 7 days before and 14 days after tMCAO. Mice in TXL post-treatment group were given TXL solution immediately after tMCAO. Rotarod test and neurological severity scores were evaluated at 1-14 days following tMCAO. Brains were harvested for examining infarct volume, edema formation, and immunofluorescent staining at 1 and 3 days after tMCAO. Cytokines IL-6, IL-1ß and TNF-α mRNA expression, and BBB permeability were further examined by RT-PCR and immunostaining. RESULTS: TXL pre-post treatment improved neurobehavioral outcomes and reduced infarct volume compared to the control (p<0.05). Meanwhile, hemispheric swelling, Evans blue and IgG protein extravasation reduced, while TJ protein expression up-regulated in pre-post treatment group (p<0.05). Further study indicated that infarct volume was smaller and BBB damage was less severe in TXL pre-post treatment group compared to TXL pre-treatment alone. It was noted that fewer myeloperoxidase (MPO) positive cells and less cytokines IL-6, IL-1ß and TNF-α expression in pre-post treatment group compared to the control group (p<0.05). CONCLUSIONS: TXL pre-treatment and pre-post treatment effectively protected the brain from BBB disruption via alleviating inflammatory response. Moreover, pre-post treatment has better outcomes, suggesting that continuous administration of TXL before and throughout ischemia period is necessary because of multiple functions of TXL.

Pharmaceutical care issues identified by pharmacists in patients with diabetes, hypertension or hyperlipidaemia in primary care settings.

BACKGROUND: The roles of pharmacists have evolved from product oriented, dispensing of medications to more patient-focused services such as the provision of pharmaceutical care. Such pharmacy service is also becoming more widely practised in Malaysia but is not well documented. Therefore, this study is warranted to fill this information gap by identifying the types of pharmaceutical care issues (PCIs) encountered by primary care patients with diabetes mellitus, hypertension or hyperlipidaemia in Malaysia. METHODS: This study was part of a large controlled trial that evaluated the outcomes of multiprofessional collaboration which involved medical general practitioners, pharmacists, dietitians and nurses in managing diabetes mellitus, hypertension and hyperlipidaemia in primary care settings. A total of 477 patients were recruited by 44 general practitioners in the Klang Valley. These patients were counselled by the various healthcare professionals and followed-up for 6 months. RESULTS: Of the 477 participants, 53.7% had at least one PCI, with a total of 706 PCIs. These included drug-use problems (33.3%), insufficient awareness and knowledge about disease condition and medication (20.4%), adverse drug reactions (15.6%), therapeutic failure (13.9%), drug-choice problems (9.5%) and dosing problems (3.4%). Non-adherence to medications topped the list of drug-use problems, followed by incorrect administration of medications. More than half of the PCIs (52%) were classified as probably clinically insignificant, 38.9% with minimal clinical significance, 8.9% as definitely clinically significant and could cause patient harm while one issue (0.2%) was classified as life threatening. The main causes of PCIs were deterioration of disease state which led to failure of therapy, and also presentation of new symptoms or indications. Of the 338 PCIs where changes were recommended by the pharmacist, 87.3% were carried out as recommended. CONCLUSIONS: This study demonstrates the importance of pharmacists working in collaboration with other healthcare providers especially the medical doctors in identifying and resolving pharmaceutical care issues to provide optimal care for patients with chronic diseases.

[Perfusion-weighted magnetic resonance imaging for monitoring vascularization in tissue-engineered bone in rhesuses].

OBJECTIVE: To assess the value of perfusion-weighted magnetic resonance (MR) imaging (PWMRI) in monitoring vascularization in tissue-engineered bone graft. METHODS: Tibial diaphyseal defect of 20 mm was induced in 25 lower limbs of 13 rhesuses and fixed with an AO reconstruction plate with 7 holes. The monkeys were randomized into 5 groups according to the materials used for defect filling: group A, with beta-tricalcium phosphate (beta-TCP), bone marrow stromal cells (BMSCs) and blood vessel bundles; group B, with beta-TCP and blood vessel bundles; group C, with beta-TCP and BMSCs; group D, with beta-TCP, and group E without filling. PWMRI, X-ray, and radionuclide imaging were carried out at weeks 4, 8, 12 postoperatively. The maximum slope rates of the single intensity-time curve (SS(max)) and the baseline values (SI(baseline)) on the same time points were calculated. Transmittances on the X-ray films and isotope counts in the region of interest (ROI) were assessed and calculated. RESULTS: Compared with other groups, group A showed the highest SS(max) at weeks 4, 8, and 12 postoperatively, and its SS(max) at week 8 was significantly higher than that at week 4 (P=0.003). The SS(max) was positively related to isotope counts in ROI at week 8 after operation (r(s)=0.899, P=0.038), and inversely related to transmittance on X-ray films at week 12 (r(s)=-0.892, P=0.042). CONCLUSION: The SS(max) of the single intensity-time curve can accurately reflect the vascularization of the tissue-engineered bone graft, and PWMRI allows sensitive, quantitative, noninvasive and radiation-free vascularization monitoring.

[Long-term observation of large weight-bearing bone defect in goats repaired with tissue engineering technique].

OBJECTIVE: To observe the long-term effect of tissue engineering-based repair of large weight-bearing bone defect in goats, and the final outcome of the scaffold material coral hydroxyapatite (CHAP) in vivo. METHODS: Fifteen Chinese goats were subjected to operations to induce a 2-cm left tibial diaphyseal defect, which was filled subsequently with CHAP and bone marrow stromal stem cells (BMSCs). The repaired defects were evaluated by ECT, X-ray and histology in the early stage and at 6, 12, 18, and 24 months postoperatively. RESULTS: ECT showed good bone regeneration and revascularization within 2 months postoperatively. X-ray and histology displayed eccentric and gradual bone regeneration in the early stage, and the tissue-engineered bone graft was firmly healed with the goat tibia. X-ray and histological examination at 6, 12, 18, 24 months postoperatively revealed moulding of the new bones and medullary cavity recanalization, and the structure of CHAP disappeared and gradually integrated into the new bones. CONCLUSION: Tissue-engineered bone is capable of total repair of large bone defect in goats by forming normal functional new bones. CHAP can be eventually degraded completely and become the component of the newly generated bones.