Elevating herbivore-induced JA-Ile enhances potato resistance to the polyphagous beet armyworm but not to the oligophagous potato tuber moth.

BACKGROUND: The oligophagous potato tuber moth (PTM), Phthorimaea operculella, and the polyphagous beet armyworm (BAW), Spodoptera exigua, are two destructive pests of potato, and infestations can lead to serious reduction in potato yield. However, potato plant responses to the two herbivories are only poorly understood. Endogenous jasmonoyl-isoleucine (JA-Ile) is a signal responsible for the induction of plant anti-herbivore defenses. Elevation of JA-Ile by blocking its catabolism is considered to be an effective and sustainable approach to enhance plant resistance to insect pests. However, it is not clear whether this approach can enhance potato resistance to PTM and BAW. RESULTS: We demonstrated that the transcriptional changes induced by simulated PTM and BAW feeding overlap to a large extent, and that 81.5% of the PTM- and 90.5% of the BAW-responsive genes were commonly regulated. We also generated potato transgenic lines, irStCYP94B3s, in which the three JA-Ile hydroxylases were all simultaneously silenced. These lines exhibited enhanced resistance only to BAW, but not to PTM, although levels of JA-Ile and its downstream induced defensive chemicals, including caffeoylputrescine, dicaffeoylspermidine, lyciumoside II, and the nicotianosides I, II, and VII, were all present at higher levels in PTM-infested than in BAW-infested irStCYP94B3s lines. CONCLUSION: Our results provide support for the hypothesis that StCYP94B3 genes are able to act as potential targets for the control of polyphagous insect pests in potato, and reveal that the oligophagous PTM has evolved an effective mechanism to cope with JA-Ile-induced anti-herbivore defenses. © 2022 Society of Chemical Industry.

Prevalence and molecular characterization of alpha and beta-Thalassemia mutations among Hakka people in southern China.

Our aim was to investigate molecular features of thalassemia for proper clinical consultation and prevention in Heyuan. In our research, a total of 25,437 positive screening subjects were further subjected to a genetic analysis of α-thalassemia (α-thal) and ß-thalassemia (ß-thal). The deletion of α-thal mutation was tested by Gap-PCR, while the non-deletion of α-thal and ß-thal mutation were identified by the PCR-reverse dot blot (PCR-RDB) technique. Nested PCR detected Hkαα/-- SEA and Hkαα/αα. Among the 25,437 positive screening subjects, 44.09% (11216/25437) subjects were bearers of thalassemia variations, and 30.85% (7847/25437) subjects showed α-thal changes alone. Among the 23 genotypes with α-thal mutation alone, the three common genotypes were --SEA/αα(68.34%), -α3.7/αα(16.44%), and -α4.2/αα(6.38%). Of the 11.50% (2924/25437) subjects and 29 genotypes with ß-thal mutation alone, the three common genotypes were ßCD41-42/ßN(36.22%), ßIVS-II-654/ßN(30.88%), and ß-28/ßN(13.47%). Additionally, of the 1.75% (445/25437) subjects and 55 genotypes showed both α- and ß-thal mutations. We also identified 269 cases of Hb H and six patients of Hkαα. Furthermore, the common genotypes of α-thal and ß-thal mutations were consistent with allele frequencies of mutations. Our study establishes molecular features of thalassemia among Hakka people in Heyuan. It will be useful for developing strategies to prevent thalassemia.

Fe2 PO5 -Encapsulated Reverse Energetic ZnO/Fe2 O3 Heterojunction Nanowire for Enhanced Photoelectrochemical Oxidation of Water.

Zinc oxide is regarded as a promising candidate for application in photoelectrochemical water oxidation due to its higher electron mobility. However, its instability under alkaline conditions limits its application in a practical setting. Herein, we demonstrate an easily achieved wet-chemical route to chemically stabilize ZnO nanowires (NWs) by protecting them with a thin layer Fe2 O3 shell. This shell, in which the thickness can be tuned by varying reaction times, forms an intact interface with ZnO NWs, thus protecting ZnO from corrosion in a basic solution. The reverse energetic heterojunction nanowires are subsequently activated by introducing an amorphous iron phosphate, which substantially suppressed surface recombination as a passivation layer and improved photoelectrochemical performance as a potential catalyst. Compared with pure ZnO NWs (0.4 mA cm-2 ), a maximal photocurrent of 1.0 mA cm-2 is achieved with ZnO/Fe2 O3 core-shell NWs and 2.3 mA cm-2 was achieved for the PH3 -treated NWs at 1.23 V versus RHE. The PH3 low-temperature treatment creates a dual function, passivation and catalyst layer (Fe2 PO5 ), examined by X-ray photoelectron spectroscopy, TEM, photoelectrochemical characterization, and impedance measurements. Such a nano-composition design offers great promise to improve the overall performance of the photoanode material.

Assembly of g-C3N4-based type II and Z-scheme heterojunction anodes with improved charge separation for photoelectrojunction water oxidation.

Graphitic carbon nitride (g-C3N4) has been widely studied as a metal-free photocatalyst, leading to some excellent results; however, the rapid recombination of photogenerated charge carriers substantially limits its performance. Here, we establish two types of g-C3N4-based heterojunction (type II and nonmediator assisted Z-scheme) photoanodes on a transparent conducting substrate via coupling with rod-like and nanoparticulate WO3, respectively. In these composites, g-C3N4 film grown by electrophoretic deposition of exfoliated g-C3N4 serves as the host or guest material. The optimized type II WO3/g-C3N4 composite exhibits an enhanced photocurrent of 0.82 mA cm-2 at 1.23 V vs. RHE and an incident photo-to-current conversion efficiency (IPCE) of 33% as compared with pure WO3 nanorods (0.22 mA cm-2 for photocurrent and 15% for IPCE). Relative to pure g-C3N4 film (with a photocurrent of several microampere and an IPCE of 2%), a largely improved photocurrent of 0.22 mA cm-2 and an IPCE of 20% were acquired for the Z-scheme g-C3N4/WO3 composite. The enhancement can be attributed to accelerated charge separation in the heterointerface because of the suitably aligned band gap between WO3 and g-C3N4, as confirmed by optical spectroscopy and ultraviolet photoelectron spectroscopy (UPS) analysis. The photocatalytic process and mechanism of the g-C3N4-based heterojunctions are proposed herein, which potentially explain the origin of the enhanced photoelectrochemical performance. This achievement and the fundamental information supplied here indicate the importance of rationally designing heterojunction photoelectrodes to improve the performance of semiconductors. This is particularly important for materials such as pure g-C3N4 and WO3, as their photoactivities are strongly restricted by high recombination rates.

A nanostructured hematite film prepared by a facile "top down" method for application in photoelectrochemistry.

To overcome tough conditions currently used for the preparation of nanostructured hematite films on a conducting substrate, a rational and easy method of chemical etching involving Fe3+ release and material growth in the presence of OH- has been developed. By carefully tuning the parameters influencing the morphologies of hematite, including the synthetic procedure, the concentration of etching solution, temperature, etching time and the morphology controlling surfactant, hematite films grown on iron foil with various morphologies (e.g. nanorod, nanowire, ultrathin nanoflake and cauliflower-like shape) have been achieved. In particular, it is found that F- is an effective surfactant to control the morphology as well as the crystallization process of hematite. Ultrathin nanoflakes having a minimized feature size exhibit the best photocurrent of 0.5 mA cm-2 (1.23 V vs. RHE, RHE is reversible hydrogen electrode) among the samples tested as a result of facilitated hole diffusion to the electrolyte and thus lowered carrier recombination. Compared with pristine hematite, a nearly tripled photocurrent is observed when H2O2 is added in the electrolyte as a hole scavenger, suggesting the presence of a charge injection barrier in the surface of samples. According to this, the strategy of Co2+ treatment is utilized and the improved photocurrent is seen, likely due to the improved water oxidation kinetics and surface state passivation. We believe that this convenient and economical method can be extended to the synthesis of other alkaline metal oxide nanomaterials as long as the redox potential of S2O82-/SO42- is higher than Mn+/M (M refers to metal).

Prevalence and genotype distribution of human papillomavirus among Hakka women in China.

BACKGROUND: Human papillomavirus (HPV) infection is the primary risk factor for cervical cancer. HPV genotypes are associated with varying degrees of pathogenicity. To better formulate strategies for cervical cancer prevention, we investigated the population-specific distribution of HPV genotypes, including those with high carcinogenicity. METHODS: From January to December 2012, a cervical cancer-screening program for HPV infection in Hakka women of Heyuan City Guangdong province was conducted. Of 736,000 women residents, 8,284 volunteers were recruited. The cytology specimens of 107 women were not adequate and excluded. Thus, 8,177 women submitted to polymerase chain reaction (PCR) sequencing of 16 HPV genotypes via MassARRAY spectrometry. RESULTS: Risk stratification based on genotypes indicated that the prevalence of overall, high-risk, and low-risk HPV infections was 12.27%, 14.20%, and 0.79%, respectively. Of the 1,003 women positively infected, 82.75% were infected with a single HPV type; 17.25% were infected with ≥2 types. Analysis revealed a U-shaped curve in HPV prevalence that correlated with age group, with peaks at ages 18-24 y (22.03%) and 60-65 y (25%). The most frequently detected HPV genotype was HPV-52 (26.81%), and then HPV-16 (17.54%), HPV-58 (14.25%), HPV-18 (10.16%), HPV-68 (8.27%), HPV-39 (5.68%), and HPV-51 (5.38%). CONCLUSIONS: HPV-52 is the most prevalent genotype infecting Hakka women. Therefore, vaccination against HPV-52 is imperative. The prevalence of HPV infection is highest in the younger (18-24 y) and older (60-65 y) age groups, indicating that screening for HPV in Hakka women should be performed early and maintained in the elderly.