Search

Luminescent cuprous complexes are an important class of coordination compounds due to their relative abundance, low cost and ability to display excellent luminescence. The title heteroleptic cuprous complex, [2,2′-bis(diphenylphosphanyl)-1,1′-binaphthyl-κ2 P,P′](2-phenylpyridine-κN)copper(I) hexafluoridophosphate, rac-[Cu(C44H32P2)(C11H9N)]PF6, conventionally abbreviated rac-[Cu(BINAP)(2-PhPy)]PF6 (I), where BINAP and 2-PhPy represent 2,2′-bis(diphenylphosphanyl)-1,1′-binaphthyl and 2-phenylpyridine, respectively, is described. In this complex, the asymmetric unit consists of a hexafluoridophosphate anion and a heteroleptic cuprous complex cation, in which the cuprous centre in a CuP2N coordination triangle is coordinated by two P atoms from the BINAP ligand and by one N atom from the 2-PhPy ligand. Time-dependent density functional theory (TD–DFT) calculations show that the UV–Vis absorption of I should be attributed to ligand-to-ligand charge transfer (LLCT) characteristic excited states. It was also found that the paper-based film of this complex exhibited obvious luminescence light-up sensing for pyridine.

Mining causes extreme heavy metal (HM) contamination to surrounding environments and poses threats to soil microbial community. The effects of HMs on soil microbial communities are not only related to their total amounts but also associated with the distribution of chemical fractions. However, the effects of chemical fractions on soil microbes and their interactions remain largely unclear. Here we investigated soil physicochemical properties and bacterial and fungal communities of soil samples from the control area and lightly (L), moderately (M), and heavily (H) contaminated areas, respectively, which were collected from long-term Pb-Zn slag contamination area in the southern China. The results showed that bacterial and fungal community composition and structure were significantly affected by HMs, while community diversity was not significantly affected by HMs. The critical environmental factor affecting bacterial and fungal communities was pH, and the impacts of chemical fractions on their changes were more significant than the total amounts of HMs. Variance partitioning analysis (VPA) revealed fungal community changes were mostly driven by HM total amounts, but bacterial community changes were mostly driven by soil chemical properties. Co-occurrence network indicated that interactions among species of fungal network were sparser than that of bacterial network, but fungal network was more stable, due to a more significant number of keystone taxa and a lower percentage of positive associations. These illustrated that the fungal community might serve as indicator taxa for HM-contaminated status, and specific HM-responsive fungal species such as Triangularia mangenotii, Saitozyma podzolica, and Cladosporium endophytica, and genus Rhizophagus can be considered relevant bioindicators due to their less relative abundance in contaminated areas. Additionally, HM-responsive bacterial OTUs representing five genera within Sulfurifustis, Thiobacillus, Sphingomonas, Qipengyuania, and Sulfurirhabdus were found to be tolerant to HM stress due to their high relative abundance in contaminated levels.

Grain crushing underpins key mechanical behaviours of granular materials. A variety of factors, including grading, particle shapes and loading conditions, have been recognised to affect the crushability of grains and the overall behaviour of a granular material. Among them, the role of intermediate principal stress in a general stress condition on the shear behaviour of crushable granular sand remains less understood, owing to the scarcity of experimental data and analytical tools available. In this paper, a multi-scale computational approach is employed to investigate the shear behaviour of crushable granular sand under general stress conditions with varying intermediate principal stresses and confining pressures. The computational approach features multi-scale coupling between non-smooth contact dynamics and peridynamics, and offers a rigorous way to consider the intertwined evolution of particle size and shape during the process of grain crushing. The numerical study helps to quantify comprehensively and analyse the grain crushing-induced changes of macro- and micro-scale material behaviours including strength, deformability, particle size and shape evolution, particle-scale forces and contact conditions, and the development of anisotropy. The competition between a void-filling mechanism due to grain size change and enhanced friction and interlocking due to grain shape change in dictating the deformation of crushable sand is further discussed. The findings offer insights into the complex behaviours of crushable granular materials under general stress conditions and facilitate future development of physics-based constitutive theories on crushable sand.

Quinoa starch granular structure as affected by nonenyl succinic anhydride (NSA) substitution was investigated by multiple approaches, including scattering, spectroscopic, and microscopic techniques. The modification had little impact on the morphology of starch granules. The NSA substitution was found mainly in the amorphous lamellae and amorphous growth rings. The NSA modification increased the thickness of the amorphous lamellae. The homogeneity of the ordered structure in the granules was improved, probably because the NSA modification reduced the amount of defects in the semi-crystalline growth ring. Compared to other chemical modifications such as acylation, succinylation was more effective in modifying the starch lamellar structure. A possible reaction pattern of NSA modification on quinoa starch is proposed, in which the NSA modification may follow the sequence of amorphous growth rings, the amorphous matrices among blocklets, amorphous and crystalline lamellae in semi-crystalline growth rings. This study provides new insights on the structural changes of starch granules induced by succinylation on the supramolecular level.

Genome-wide association studies (GWAS) have markedly advanced our understanding of the genetics of Parkinson’s disease (PD), but they currently do not account for the full heritability of PD. In many cases it is difficult to unambiguously identify a specific gene within each locus because GWAS does not provide functional information on the identified candidate loci. Here we present an integrative approach that combines transcriptome-wide association study (TWAS) with high-throughput neuronal dysfunction analyses in Drosophila to discover and validate candidate PD genes. We identified 160 candidate genes whose misexpression is associated with PD risk via TWAS. Candidates were validated using orthogonal in silico methods and found to be functionally related to PD-associated pathways (i.e. endolysosome). We then mimicked these TWAS-predicted transcriptomic alterations in a Drosophila PD model and discovered that 50 candidates can modulate α-Synuclein(α-Syn)-induced neurodegeneration, allowing us to nominate new genes in previously known PD loci. We also uncovered additional novel PD candidate genes within GWAS suggestive loci (e.g. TTC19, ADORA2B, LZTS3, NRBP1, HN1L), which are also supported by clinical and functional evidence. These findings deepen our understanding of PD, and support applying our integrative approach to other complex trait disorders.

Peach bacterial spot caused by Xanthomonas arboricola pv. pruni has become widespread in most peach-producing areas of China and has caused devastating losses to the peach industry. However, little is known about the population biology and epidemiology of X. arboricola pv. pruni in China, thus no effective management strategy is available. Altogether, 321 symptomatic samples of peach bacterial spot from 12 provinces in China were collected from which 612 bacterial isolates were obtained. Based on 16S rDNA sequence comparison in GenBank, the obtained isolates were identified as Pantoea spp. (514) and Xanthomonas spp. (98). The pathogenicity test demonstrated that the causal agent of the peach bacterial spot was the Xanthomonas spp. instead of the Pantoea spp. Based on morphological observation, physiological and biochemical characterization, and molecular identification, the Xanthomonas spp. were further identified to be X. arboricola pv. pruni. Then, 41 X. arboricola pv. pruni isolates representing different populations were selected and analyzed with repetitive element sequence based-PCR and intersimple sequence repeat markers to understand the genetic diversity and population structure along with four X. arboricola pv. pruni isolates from plum and three isolates of X. arboricola pv. juglandis as comparison. A total of 98 polymorphic alleles were identified, with a mean value of percentage of polymorphic loci of 14. Genetic diversity and phylogenetic analysis revealed the profound heterogeneity between X. arboricola pv. juglandis and X. arboricola pv. pruni, moderate genetic differentiation within X. arboricola pv. pruni, and obvious host specificity but weak geographical differentiation in X. arboricola population. Finally, the efficiency of bactericides on X. arboricola pv. pruni was evaluated in vitro and in vivo. The parallel repeated field trials in two orchards demonstrated that 80% Mancozeb (1:800) and 47% Kocide (1:800, 1:1,500, and 1:2,000) had excellent control efficacies for X. arboricola pv. pruni, especially as the control efficacy of Kocide could even reach 90%. This study conducted a systematic investigation for the occurrence, population variance, and chemical control of X. arboricola pv. pruni. It improved the understanding of the pathogen populations of peach bacterial spot in China and provided solid theoretical and practical guidance for X. arboricola pv. pruni control.

Past studies have shown mixed results of postoperative radiation (PORT) for pN2 NSCLC patients. We hypothesize that PORT can improve overall survival (OS) in pN2 NSCLC patients with high lymph node ratio (LNR).The National Cancer Database was queried for non-metastatic pN2 NSCLC patients with R0 surgery and adjuvant chemotherapy from 2004 to 2016. Cox models were used to assess the impact of PORT and LNR on OS adjusted for patient characteristics and treatment information.Among 4,050 patients, 1,728 (42.7%) had PORT. There was increased use of IMRT in the more recent period (53.8% in 2010-2016 vs 24.0% in 2004-2009). PORT was associated with better OS in the overall cohort. For patients with inadequate lymph node dissection (LND), PORT marginally improved OS (HR = 0.91, p = 0.058). Among patients with adequate LND, PORT did not improve OS for patients with LNR15% (HR = 1.11, p = 0.21), or LNR 15-29% (HR = 1.03, p = 0.73), but it significantly improved OS for patients with LNR ≥30% (HR = 0.83, p = 0.006). In patients with LNR≥30%, IMRT significantly improved OS when compared to no PORT (HR = 0.75, p0.05) while 3D RT did not (HR = 0.89, p = 0.32).PORT was associated with better survival for pN2 NSCLC patients after R0 resection, adequate LND with high LNR, after accounting for multiple confounders. Among the whole cohort, most of the OS benefits of PORT were driven by patients with inadequate LND, high LNR or use of IMRT.