Petrogenesis and Tectonic Implications of the Paleoproterozoic A-Type Granites in the Xiong’ershan Area along the Southern Margin of the North China Craton

Paleoproterozoic A-type granites are widely distributed in the southern margin of the North China Craton(SNCC),providing important information for understanding the Paleoproterozoic tectonic regimes in this area.This paper reports newly obtained whole-rock compositions and zircon U-Pb ages for the Tieluping syenogranite porphyry(TLP)and Huoshenmiao alkali granite porphyry(HSM)in the SNCC.Zircons from the TLP and HSM have U-Pb ages of 1805±12 and 1792±14 Ma,respectively.These ages are taken to date the emplacement of these intrusions.They had high total alkali contents(K_(2)O+Na_(2)O>7.13 wt.%),with high 10000×Ga/Al ratios(3.06–3.41)and Zr+Y+Nb+Ce values(709 ppm–910 ppm)as well as high zircon saturation temperatures(864–970℃),indicative of A-type granite affinities.High Y/Nb(1.75–3.32),Ce/Nb(7.72–9.72),and Yb/Ta(2.89–5.60)ratios suggested that TLP and HSM belonged to the A2-type granite.The negative whole rockε_(Nd)(t)values(−8.4 to−6.6)and negative zirconε_(Hf)(t)values(−15.9 to−6.3)confirmed that TLP and HSM were likely generated by the partial melting of an ancient continental crust.TheεHf(t)(−7.4 to+4.0)values of inherited zircons in the TLP suggested that they were derived from the partial melting of Archean basement rocks.Considering the geochemical similarity of the 1.80 Ga A-type granitoids in the SNCC,we propose that the TLP and HSM were formed in a post-collisional regime that was likely associated with the break-off of the Paleoproterozoic subducted slab.Upwelling of the asthenosphere provided huge heat to generate the regional 1.80 Ga A-type granite in the SNCC.

Recent progress and challenges in the treatment of spinal cord injury

Spinal cord injury(SCI)disrupts the structural and functional connectivity between the higher center and the spinal cord,resulting in severe motor,sensory,and autonomic dysfunction with a variety of complications.The pathophysiology of sci is complicated and multifaceted,and thus individual treatments acting on a specific aspect or process are inadequate to elicit neuronal regeneration and functional recovery after ScI.Combinatory strategies targeting multiple aspects of scI pathology have achieved greater beneficial effects than individuai therapy alone.Although many problems and challenges remain,the encouraging outcomes that have been achieved in preclinical models offer a promising foothold for the development of novel clinical strategies to treat scl.In this review,we characterize the mechanisms underlying axon regeneration of adult neurons and summarize recent advances in facilitating functional recovery following scI at both the acute and chronic stages.In addition,we analyze the current status,remaining problems,and realistic challenges towards clinical translation.Finally,we consider the future of scI treatment and provide insights into how to narrow the translational gap that currently exists between preclinical studies and clinical practice.Going forward,clinical trials should emphasize multidisciplinary conversation and cooperation to identify optimal combinatorial approaches to maximize therapeuticbenefitinhumanswithscl.

Rice OsUBR7 modulates plant height by regulating histone H2B monoubiquitination and cell proliferation

Plant height is an important agronomic trait for lodging resistance and yield.Here,we report a new plantheight-related gene,OsUBR7 in rice(Oryza sativa L.);knockout of OsUBR7 caused fewer cells in internodes,resulting in a semi-dwarf phenotype.OsUBR7 encodes a putative E3 ligase containing a plant homeodomain finger and a ubiquitin protein ligase E3 component N-recognin 7(UBR7)domain.OsUBR7 interacts with histones and monoubiquitinates H2B(H2Bub1)at lysine148 in coordination with the E2 conjugase OsUBC18.OsUBR7 mediates H2Bub1 at a number of chromatin loci for the normal expression of target genes,including cell-cycle-related and pleiotropic genes,consistent with the observation that cell-cycle progression was suppressed in the osubr7 mutant owing to reductions in H2Bub1 and expression levels at these loci.The genetic divergence of OsUBR7 alleles among japonica and indica cultivars affects their transcriptional activity,and these alleles may have undergone selection during rice domestication.Overall,our results reveal a novel mechanism that mediates H2Bub1 in plants,and UBR7 orthologs could be utilized as an untapped epigenetic resource for crop improvement.

Cryo-EM structures of the mammalian endo-lysosomal TRPML1 channel elucidate the combined regulation mechanism

TRPML1 channel is a non-selective group-2 transient receptor potential （TRP） channel with Ca2＋ permeability. Located mainly in late endosome and lysosome of all mammalian cell types, TRPML1 is indispensable in the processes of endocytosis, membrane trafficking, and lysosome biogenesis. Mutations of TRPML1 cause a severe lysosomal storage disorder called mucolipidosis type IV （MLIV）. In the present study, we determined the cryo-electron microscopy （cryo-EM） structures of Mus musculus TRPML1 （mTRPMLI） in lipid nanodiscs and Amphipols. Two distinct states of mTRPML1 in Amphipols are added to the closed state, on which could represent two different confirmations upon activation and regulation. The polycystin-mucolipin domain （PMD） may sense the luminal/extracellular stimuli and undergo a ＂move upward＂ motion during endocytosis, thus triggering the overall conformational change in TRPMLI. Based on the structural comparisons, we propose TRPML1 is regulated by pH, Ca2＋, and phosphoinosi- tides in a combined manner so as to accommodate the dynamic endocytosis process.

Fundamental understanding of high-capacity lithium-excess cathodes with disordered rock salt structure

As a new class of lithium rich cathodes,disordered rock-salt cathodes have been of primary interest,because of their ability to deliver a promisingly high capacity up to 300 mAh/g.Nevertheless,some fundamental issues are yet to be fully understood and a comprehensive mastering of their solid-state chemistry,kinetics and thermal stability is required.Here,we select a high capacity cation-disordered positive electrode-Li_(1.2)Ni_(0.4)Nb_(0.4)O_(2)as a model compound to study intrinsic reaction mechanism,including charge compensation mechanism,kinetics,thermal stability,and structural evolution.By combining soft and hard X-ray absorption spectroscopy(XAS),X-ray photoelectron spectroscopy(XPS)with operando and exsitu differential scanning calorimetry(DSC),galvanostatic intermittent titration technique(GITT),cyclic voltammetry(CV),and X-ray diffraction(XRD),we present holistic information on disordered rock-salt cathode.This work provides beneficial insights into designing and tailoring new positive electrodes with disordered rock-salt structure.