Genetic architecture of quantitative trait loci(QTL)for FHB resistance and agronomic traits in a hard winter wheat population

Wheat resistance to Fusarium head blight(FHB)has often been associated with some undesirable agronomic traits.To study the relationship between wheat FHB resistance and agronomic traits,we constructed a linkage map of single nucleotide polymorphisms(SNPs)using an F6:8 population from G97252WG97380A.The two hard winter wheat parents showed contrasts in FHB resistance,plant height(HT),heading date(HD),spike length(SL),spike compactness(SC),kernel number per spike(KNS),spikelet number per spike(SNS),thousand-grain weight(TGW)and grain size(length and width).Quantitative trait locus(QTL)mapping identified one major QTL(QFhb.hwwg-2DS)on chromosome arm 2DS for the percentage of symptomatic spikelets(PSS)in the spike,deoxynivalenol(DON)content and Fusarium damaged kernel(FDK).This QTL explained up to 71.8%of the phenotypic variation for the three FHB-related traits and overlapped with the major QTL for HT,HD,SL,KNS,SNS,TGW,and grain size.QTL on chromosome arms 2AL,2DS,3AL and 4BS were significant for the spike and grain traits measured.G97252W contributed FHB resistance and high SNS alleles at QFhb.hwwg-2DS,high KNS alleles at the QTL on 2AL and 2DS,and high TGW and grain size alleles at QTL on 3AL;whereas G97380A contributed high TGW and grain size alleles at the QTL on 2AL and 2DS,respectively,and the high KNS allele at the 4BS QTL.Combining QFhb.hwwg-2DS with positive alleles for spike and grain traits from other chromosomes may simultaneously improve FHB resistance and grain yield in new cultivars.

Photoresponse Characteristics of Chamaenerion spp. in Mount Shergyla

Chamaenerion spp.( Onagraceae) are a class of ecological restoration medicinal herbs. Mount Shergyla has three species and one variant of Chamaenerion. Studying their photoresponse characteristics and elucidating their adaptation and physiological response to the photosynthetic characteristics of the environment is the basis for the development and protection of the plant resources of the genus Chamaenerion. In this experiment,Li-6400 portable photosynthesis instrument was used to study the photoresponse characteristics of C. spp. in Mount Shergyla,and the photoresponse curves were fitted using a right-angle hyperbolic correction model. The results showed that Chamaenerion conspersum has low light compensation point[4. 931 μmol/( m^2·s) ],high light saturation point[1 000 μmol/( m^2·s) ],and strongest adaptability to light,which is one of the determinants of its distribution at each elevation of Mount Shergyla. Chamaenerion angustifolium subsp. circumvagum has higher light compensation point [11. 848 μmol/( m^2·s) ],low light saturation point[800 μmol/( m^2·s) ],and weakest adaptability to light,and it is a typical sciophilous plant. This result is consistent with the habitats( Rhododendron wardii shrub and spruce forest margin) that C. angustifolium are distributed in Mount Shergyla. C. angustifolium and Chamaenerion latifolium have higher light compensation points and higher light saturation points,suggesting that the adaptability of C. angustifolium and C. latifolium to the light environment is weak. This can also explain the narrow distribution of C. angustifolium and C. latifolium in Mount Shergyla. There are certain degree of differences in the responses of net photosynthetic rate( Pn),intercellular CO_2 concentration( Ci),stomatal conductance( Gs) and transpiration rate( Tr) of the three species and one variant of Chamaenerion to different photosynthetically active radiation( PAR). With the increase of light intensity,the Pn,Gs and Tr of Chamaenerion spp. increased significantly,and the Ci decreased. The Pn of C. conspersum and C. latifolium differed insignificantly,but they were both higher than that of C. angustifolium. The Pn of C. angustifolium subsp. circumvagum was the lowest. The Gs of C. conspersum and C. latifolium differed insignificantly,but they were both higher than that of C. angustifolium subsp. circumvagum. The Gs of C. angustifolium was the lowest. There was no obvious difference in Ci between C. angustifolium and C. latifolium,of which the Ci was both higher than that of C. conspersum. The Ci of C. angustifolium subsp. circumvagum was the lowest. C. angustifolium subsp. circumvagum had the highest Tr,followed by C. angustifolium and C. conspersum( no obvious difference),and C. latifolium had the lowest Tr. The light utilization efficiency of C. spp. ranked as C. angustifolium subsp. circumvagum < C. angustifolium < C. latifolium < C. conspersum. The light suppression phenomenon was evident in C. angustifolium,C. angustifolium subsp. circumvagum and C. latifolium. C. conspersum is most suitable for application under high light intensity conditions in Tibet. C. angustifolium,C. angustifolium subsp. circumvagum and C. latifolium should be shaded properly under conditions of high light intensity in the cultivation process,while C. conspersum needs to be supplemented with light during the cultivation process.

Characterisation of Bacteria⁃Based Concrete Crack Rejuvenation by Externally Applied Repair

Microbiologically⁃induced calcite⁃precipitation(MICP)has been increasingly studied in structural repair including self⁃healing and external applications.Among various MICP pathways,enzymatic urea hydrolysis is suggested to be applied as external repair instead of self⁃healing.This study comprehensively characterised the enzymatic urea hydrolysis pathway in physical,impermeable,and mechanical rejuvenation of concrete cracks.The visual quality of repaired structures was presented,and the importance of humidity in the remediation of cracks was demonstrated.Moreover,this study investigated the differences in the effectiveness of repair between premixing bacteria with urea and without any premixing.With premixing,there was a concern that the accelerated reactions would precipitate calcite in the shallow spaces of the cracks and impede deeper healing.However,the observed results indicated that neither physical nor impermeable rejuvenation of concrete cracks repair would be detrimentally affected.The results obtained from this study will allow further development in commercialisation since the effectiveness of repair has been confirmed with an improvement in its efficiency.

Research on Light Response Curve Fitting Model of Four Chamaenerion Plants on the Serzilla Mountains

In order to study the applicability of different light response models to the photoresponse curves of four species of Chamaenerion, four species of Chamaenerion collected from Serzilla were used as test materials. Four common photosynthetic models were used to fit the photosynthetic response curve of the leaves. The results show that: 1) The effect of different photosynthetic response models on photosynthetic response curve of the genus chromasia was different. The fitted value of the correction model of right angled hyperbola was closest to the measured value, the R2 was 0.998, and RE was 0.216. 2) In terms of fitting the photosynthetic parameters, the initial quantum efficiency, light compensation point and dark respiration rate were suitable for fitting with non-right angle hyperbolic model. In terms of fitting the photosynthetic parameters, the initial quantum efficiency, light compensation point and dark respiration rate were suitable for fitting with non-right angle hyperbolic model. 3) The photosynthetic characteristics of C. angustifolium subsp. circumvagum reflect the negative response to high altitude radiation. Under strong radiation, the photosynthetic rate, apparent quantum efficiency, and light saturation point are low. On the other hand, C. conspersum has a positive response to high altitude radiation. C. angustifolium and C. latifolium has a higher light compensation point and higher light saturation point, but it is also positive for high altitude radiation. The response is only a choice of light intensity at different elevations, which also explains the distribution of C. angustifolium and C. latifolium in the salmonella with a single elevation, habitat, and slope.

新生儿Phelan-McDermid综合征1例

Phelan-McDermid综合征是一种罕见的常染色体显性遗传性疾病,由22号染色体长臂拷贝数缺失所致。本文报道1例以肌张力低、先天性心脏病、反复感染为主要表现的新生儿Phelan-McDermid综合征,以加强临床医生对本病的认识。

Peroxidase-mimicking evodiamine/indocyanine green nanoliposomes for multimodal imaging-guided theranostics for oral squamous cell carcinoma

Here,evodiamine(EVO)and the photosensitizer indocyanine green(ICG)were integrated into a liposomal nanoplatform for noninvasive diagnostic imaging and combinatorial therapy against oral squamous cell carcinoma(OSCC).EVO,as an active component extracted from traditional Chinese medicine,not only functioned as an antitumor chemotherapeutic agent but was also capable of 68Ga-chelation,thus working as a contrast agent for positron emission tomography/computed tomography(PET/CT)imaging.Moreover,EVO could exhibit peroxidase-like catalytic activity,converting endogenous tumor H2O2 into cytotoxic reactive oxygen species(ROS),enabling Chemo catalytic therapy beyond the well-known chemotherapy effect of EVO.As proven by in vitro and in vivo experiments,guided by optical imaging and PET/CT imaging,we show that the theragnostic liposomes have a significant inhibiting effect on in situ tongue tumor through photodynamic therapy combined with chemodynamic chemotherapy.

Re-detectable positive SARS-CoV-2 RNA tests in patients who recovered from COVID-19 with intestinal infection

Dear Editor,Severe acute respiratory syndrome coronavirus 2(SARSCoV-2),a novel coronavirus that causes Coronavirus Disease 2019(COVID-19)(Yang and Wang,2020),has spread to more than 200 countries and infected more than 9,000,000 people as of Jun 2020.Tens of thousands of patients with COVID-19 have recovered and been discharged from hospital.However,there are reports of recovered patients who subsequently tested positive for SARSCoV-2 after discharge(re-detectable positive,RP)(An et al.,2020;Lan et al.,2020),and this has led to increasing focus on the mechanism(s)underlying RP.

Next-generation sequencing revealed influenza and Chlamydia infection in recurrent pneumonia in a patient who had recovered from COVID-19

Dear Editor,The severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)was identified as the cause of an outbreak of a global pandemic of coronavirus disease 2019(COVID-19)in December 2019.1 COVID-19 often starts with nonspecific upper respiratory tract symptoms,making it difficult to distinguish from other diseases that present similar symptoms,such as fever,lung infection,and asthenia.