The Infection Control Measures Taken in MRI Examination During the COVID-19 Pandemic Prevention and Control Period

Objective:To optimize the magnetic resonance imaging(MRI)detection process in view of the COVID-19 pandemic,standardize and strengthen the infection control and management MRI rooms.Methods:According to the Technical Guide for COVID-19 Prevention and Control in Medical Institutions(3rd Edition),with reference to the current COVID-19 infection control plan,there are three aspects involved in the planning of MRI examination:MRI room management,medical staff management and protection,and patient management,especially the use of full plastic nose strip medical masks.Infection prevention measures are formulated,scientific prevention and control are made,and accurate policies are implemented.Results:MRI examination was carried out according to the infection control and management of MRI room plan during the epidemic,so as to ensure the safety of examination,the safety of patients and the safety of medical staff and no cross infection in hospital.Conclusion:The implementation of proper infection prevention measures during MRI examination in light of COVID-19 ensures that patients wear medical surgical masks with full plastic nose strips throughout the process to avoid cross-infection,ensure the safety of doctors and patients,and maintain the health of the population.

Crustal S-wave velocity structure across the northeastern South China Sea continental margin: implications for lithology and mantle exhumation

The northeastern margin of the South China Sea (SCS), developed from continental rifting and breakup, is usually thought of as a non-volcanic margin. However, post-spreading volcanism is massive and lower crustal high-velocity anomalies are widespread, which complicate the nature of the margin here. To better understand crustal seismic velocities, lithology, and geophysical properties, we present an S-wave velocity (VS) model and a VP/VS model for the northeastern margin by using an existing P-wave velocity (VP) model as the starting model for 2-D kinematic S-wave forward ray tracing. The Mesozoic sedimentary sequence has lower VP/VS ratios than the Cenozoic sequence;in between is a main interface of P-S conversion. Two isolated high-velocity zones (HVZ) are found in the lower crust of the continental slope, showing S-wave velocities of 4.0–4.2 km/s and VP/VS ratios of 1.73–1.78. These values indicate a mafic composition, most likely of amphibolite facies. Also, a VP/VS versus VP plot indicates a magnesium-rich gabbro facies from post-spreading mantle melting at temperatures higher than normal. A third high-velocity zone (VP : 7.0–7.8 km/s;VP/VS: 1.85–1.96), 70-km wide and 4-km thick in the continent-ocean transition zone, is most likely to be a consequence of serpentinization of upwelled upper mantle. Seismic velocity structures and also gravity anomalies indicate that mantle upwelling/ serpentinization could be the most severe in the northeasternmost continent-ocean boundary of the SCS. Empirical relationships between seismic velocity and degree of serpentinization suggest that serpentinite content decreases with depth, from 43% in the lower crust to 37% into the mantle.

Genetic Improvement in Juglans mandshurica and Its Uses in China:Current Status and Future Prospects

Juglans mandshurica is an economically and ecologically valuable species that is used for various construction purposes,making luxurious furniture,as food and sources of medicinal substances and landscaping because of its excellent wood,edible fruits and rich in various types of chemical compounds.In the past few decades,several genetic improvements of J.mandshurica were made,with a focus on the selection of improved varieties and on breeding technology.Many elite provenances and families were selected based on growth traits or wood properties.In recent years,with the increasing demand for high-quality seedlings in Chinese forestry production,the breeding goals of genetic improvement for J.mandshurica were redefined to include other traits,such as fruit yield and contents of medicinal component.However,the improvement processes were still slow due to the long breeding cycle and the limited use of advanced breeding technologies,resulting in the selection of fewer improved varieties.In this review,we summarized the research progresses on genetic improvements of J.mandshurica and other related works,and discussed research gaps and suggested future directions for genetic improvement of the species.The review provides valuable insight for the selection of improved varieties and production of excellent germplasms.

Granulomatosis with polyangiitis presented as multiple cutaneous abscesses after hysterectomy

To the Editor:A 62-year-old woman presented to the dermatology department with a 5-month history of multiple painless cutaneous abscesses and ulcers[Figure 1A],occurring 1 month after a transvaginal hysterectomy due to uterine prolapse.Her general condition was good before and after the surgery,with no abnormal physical signs apart from metroptosis.She reported no fever,night sweat,cough,or abdominal pain,but 10 kg weight-loss.She has no history of diabetes,autoimmune diseases,or chronic infectious diseases.There was no similar illness in her family.

Clinical and histopathological predictors of rapid kidney function decline in patients with biopsy-proven diabetic kidney disease

To the Editor:Diabetic kidney disease(DKD)has become the leading cause of end-stage kidney disease(ESKD).According to the Kidney Disease Improving Global Outcomes(KDIGO)guidelines,rapid kidney function decline in DKD is defined as an estimated glomerular filtration rate(eGFR)slope≤−5 mL∙min^(−1)∙1.73 m^(−2)·year^(−1).The prognoses of patients who experience rapid eGFR decline are usually poor.In a multicenter retrospective study,230 of 377(61%)biopsy-proven DKD patients were rapid decliners.[1]It was reported that 32%and 42%of 195 type 2 diabetes(T2D)Pima Indians with normoalbuminuria and microalbuminuria,respectively,had a rapid eGFR decline,indicating that proteinuria alone has difficulty in fully predicting rapid kidney function decline in DKD patients with T2D.[2]Therefore,it is of interest to identify more useful clinicopathological predictors of a rapid kidney function decline in T2D patients.

Population Genomic Analysis and De Novo Assembly Reveal the Origin of Weedy Rice as an Evolutionary Game

Crop weediness,especially that of weedy rice(Oryza sativa f.spontanea),remains mysterious.Weedy rice possesses robust ecological adaptability;however,how this strain originated and gradually formed proprietary genetic features remains unclear?Here,we demonstrate that weedy rice at Asian high latitudes(WRAH)is phylogenetically well defined and possesses unselected genomic characteristics in many divergence regions between weedy and cultivated rice.We also identified novel quantitative trait loci underlying weedy-specific traits,and revealed that a genome block on the end of chromosome 1 is associated with rice weediness.To identify the genomic modifications underlying weedy rice evolution,we generated the first de novo assembly of a high-quality weedy rice genome(WR04-6),and conducted a comparative genomics study between WR04-6 with other rice reference genomes.Multiple lines of evidence,including the results of demographic scenario comparisons,suggest that differentiation between weedy rice and cultivated rice was initiated by genetic improvement of cultivated rice and that the essence of weediness arose through semi-domestication.A plant height model further implied that the origin of WRAH can be modeled as an evolutionary game and indicated that strategy-based selection driven by fitness shaped its genomic diversity.

Prevalence and treatment of hypertension in China： impacts of 2017 American College of Cardiology/American Heart Association High Blood Pressure Guideline

The definition, recommended treatment thresholds and targets of hypertension have been updated in the recent 2017 American College of Cardiology/American Heart Association(ACC/AHA) Guideline for the Prevention, Detection, Evaluation and Management of High Blood Pressure in Adults. However,the impacts of this guideline on Chinese population are currently unknown. In this study, we aim to provide updated data in China using criteria from the updated guideline. A multistage, stratified sampling method was used to obtain a representative sample of 50,171 adults aged 18 years and above.Hypertension was defined as an average systolic blood pressure !130 mm Hg, or an average diastolic blood pressure !80 mm Hg, or self-reported use of antihypertensive medications in past 2 weeks. The weighted prevalence of hypertension was 60.1%(95% confidence interval [CI] 59.3%–61.0%). The treatment rate and recommended treatment rate were 16.8%(95% CI 16.1%–17.6%) and 53.7%(95% CI52.6%–54.9%), respectively; the gap was more prominent among men and participants from rural areas.Hence, the adoption of the 2017 ACC/AHA guideline will lead to a substantial increase in both prevalence and number of patients needing treatment in China. The applicability of this guideline should be carefully evaluated based on evidence from Chinese population.

Crustal velocity structure of the Northwest Sub-basin of the South China Sea based on seismic data reprocessing

The deep crustal structure of the Northwest Sub-basin(NWSB)of the South China Sea(SCS)is of great importance for understanding the tectonic nature of the continent-ocean transition(COT)and magmatism in this oceanic basin.The 2-D wide-angle reflection/refraction seismic profile OBS2006-2 is almost parallel to the extinct spreading ridge(ESR)of the NWSB.In addition to the original data,we added the data of two reprocessed OBS stations,and carried out seismic phase re-picking and travel-time imaging to obtain the crustal velocity structure along this profile.Resolution tests demonstrate that the newly acquired velocity structure is more reliable than the prior interpretation.The depth of the Moho(23.5–11.8 km)and crustal thickness(20.5–6.5 km)systematically changes from continental crust of the Xisha Block to the oceanic crust within the NWSB.The COT zone has a width of^20 km and the depth of the Moho decreases from 15.0 to 11.0 km,corresponding to a^4 km decrease in crustal thickness(6–10 km).A high velocity layer(HVL,7.2–7.4 km s–1)exists at the bottom of the crust at the location where the sharp lateral transition of the continental crust to the oceanic crust occurs.Age dating shows that the Doublepeak Seamount was formed at^23 Ma,after the cessation of the NWSB seafloor spreading(~32–25 Ma).The crust beneath the Double-peak Seamount is oceanic with a thickness of 9 km.We infer that this oceanic crust was formed by magmatic upwelling and decompression melting along a pre-existing zone of weakness.

Fault-controlled regional magmatism and mineral deposition in central Cathaysia——Evidence from ambient noise tomography

Guangdong Province in the central Cathaysian Block has two world-class metallogenic belts, namely, the Nanling and Southeastern Coastal Metallogenic Belts(NLMB and SCMB), which are spatially coincide with the major regional Ganjiang and Zhenghe-Dapu Fault Zones(GJFZ and ZDFZ). However, what roles the faults played in mineral deposition and magmatism is unclear. Using ambient noise tomography, we obtain a 3-D whole-crust shear wave velocity model. By combining available regional geophysical models, we characterize the architecture of the regional shallow lithosphere and infer its possible tectonic connection to magmatic sources, pathways and surface deposition. The results show that the study area is loosely divided by the two major faults, the GJFZ and ZDFZ, into distinct velocity domains. In the north high Vand low V/Vcrust in the NLMB imply crustal remelting, which leads to the general felsic composition. In the coastal area, the lower crustal high Vanomaly is attributed to upwelling melts associated with Cretaceous magmatic activity. Between mineral belts, a swath of crustal lowvelocity zones extend into the uppermost mantle, manifesting partial melting related to upwelling magmas that may hint at a deep origin of magma from subcrustal lithosphere and likely feed surface mineral deposits through major faults. Secondary NW-trending faults coincide with low velocities and facilitated magmatic migration. A correlation between coastward extension of low velocities and younging of the Jurassic and Cretaceous magmatism is suggestive of a combined effect of slab rollback and a change in the direction of the Paleo-Pacific subduction system. We speculate a regional fault-control model in the central Cathaysian Block for the spatial-temporal evolution of regional deformation and magmatism during the middle Mesozoic.

The complement system and autoimmune diseases

The complement system plays a key role in the pathogenesis of autoimmune diseases,which usually injures the kidney.More and more studies have shown the pathogenic role and indicated that abnormal activation of the complement system was highly involved in the outbreak of autoimmune diseases.This review mainly introduced recent studies of complement system activation contributing to the pathogenesis of autoimmune diseases,including systemic lupus erythematosus,antiphospholipid syndrome,antineutrophil cytoplasmic antibody-associated vasculitides,and so on.Understanding the pathogenic roles of complement activation in various autoimmune diseases will identify potential novel therapeutic targets on complement systems.

A Parameterization of the Canonical Bases of Affine Modified Quantized Enveloping Algebras

For a symmetrizable Kac-Moody Lie algebra g, Lusztig introduced the corresponding modified quantized enveloping algebra˙U and its canonical basis˙B given by Lusztig in 1992. In this paper, in the case that g is a symmetric Kac-Moody Lie algebra of finite or affine type, the authors define a set M which depends only on the root category R and prove that there is a bijection between M and ˙B, where R is the T^2-orbit category of the bounded derived category of the corresponding Dynkin or tame quiver. The method in this paper is based on a result of Lin, Xiao and Zhang in 2011, which gives a PBW-type basis of U^+.

Leflunomide therapy for adult patients with steroid-dependent minimal change disease or primary focal segmental glomerulosclerosis

To the Editor:Minimal change disease(MCD)and focal segmental glomerulosclerosis(FSGS)are common histological subtypes of nephrotic syndrome in adults and children.^([1,2])Corticosteroids are the first-line treatment,whereas some patients present with steroid-dependent nephrotic syndrome.Repeated treatment with steroids is required,accompanied by serious adverse effects related to prednisone monotherapy in the long term.

Association between COL4A3 variant rs55703767 and susceptibility to diabetic kidney disease in patients with type 2 diabetes mellitus:results from the INDEED cohort study

To the Editor:Diabetic kidney disease(DKD)is the leading cause of the end-stage renal disease nowadays.[1]The etiology of DKD is complex and remains largely unknown.[2]A genome-wide association study showed that a common missense variant in COL4A3,rs55703767,played a protective role in DKD in type 1 diabetes mellitus in Europeans,and this effect depended on blood glucose levels.[3]However,data from type 2 diabetes mellitus(T2DM)are insufficient.

Connotation and Determinants of Web Collective Intelligence

With continuous development of network technology, users in network community are promoted to interact deeply, and remarkable web collective intelligence emerges in the process. As a relatively new concept, the connotation of web collective intelligence is preliminarily explored in this paper, where the network community is taken as the environment, expert users as the subject, and web comments as the carrier. Meanwhile, taking Wikipedia as an example, by means of questionnaire survey and structural equation model, a more systematic index system is constructed from the perspective of user characteristics to explore determinants of web collective intelligence quality, and potential influence of user attributes on user behavior.