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On the basis of the observation of rock cores and cuttings, combining the information from thin section identification, physical properties analysis, scanning electron microscopy, X-ray diffraction, etc., the characteristics and controlling factors of the tight reservoir in the Permian Lucaogou Formation of the Yongfeng sub-sag of the Chaiwopu sag have been studied. Based on the analysis, the Lucaogou Formation in the study area can be divided into two lithological sections. The tight sandstone reservoir, characterized by low porosity and low permeability, is mainly developed in the upper section of the Lucaogou Formation. The lithology of the tight reservoirs is mainly lithic sandstone with low compositional and structural maturity. The reservoir space types mainly consist of secondary pores, including intergranular dissolution pores, intragranular dissolution pores and fractures, and the primary pores are severely destroyed. The main controlling factors of reservoirs include sedimentary facies, lithology, diagenesis, later tectonic movements and fractures, and the latter two factors have a significant impact on improving reservoir physical properties and seepage capacity. The tight reservoir has high brittleness and low water sensitivity, which is very conducive to large-scale hydraulic fracturing to transform the reservoir and improve oil and gas production capacity. [ABSTRACT FROM AUTHOR]

The novel intumescent flame retardant rigid polyurethane foams ((PEPS-RPUF) were prepared based on a P-N containing intumescent flame retardant, poly ethanediamine spirocyclic pentaerythritol bisphosphonate (PEPS). The flammability, thermal, and mechanical properties of PEPS-RPUF were discussed. Scanning electron microscopy (SEM) and compression strength tests showed PEPS exhibited favorable compatibility with polyurethane matrix and smaller negative influence on the mechanical properties of PEPS-RPUF. Cone calorimeter, vertical burning test (UL-94) and limiting oxygen index (L0I) showed when the content of PEPS was 25 pph, the peak heat release rate (PHRR) and total heat release (THR) decrease, respectively, from 75.2 to 52.2 kW [m.sup.-2] and from 5.7 to 4.1 MJ [m.sup.-2] The LOI of PEPS-RPUF could reach 27%, and a UL-94 V-0 rating was achieved. The PEPS-RPUF exhibited an outstanding water resistance that it could still obtain a V-0 rating after water soaking. Thermogravimetric analysis (TGA) showed the charring ability of PEPS-RPUF was improved greatly compared to RPUF. SEM and Fourier transform-infrared spectroscopy (FT-IR) were utilized to characterize the surface morphology and chemical structure of the intumescent chars formed from PEPS-RPUF. The results indicated the chars were compact and smooth, which was a critical factor for protecting the substrate material from burning. POLYM. ENG. SCI., 53:2478-2485,2013. © 2013 Society of Plastics Engineers, INTRODUCTION Rigid polyurethane foam (RPUF) has a wide range of applications such as insulation, packaging, etc. due to its excellent properties. However, like the majority of organic materials, the RPUF [...]

BACKGROUND Most countries set regulatory values for the total trace element (TE) concentrations in soil, although there is growing interest in using a risk‐based approach to evaluate the bioavailable TE using dilute salt extractants or other soil parameters, including pH and organic carbon. The present study compares the current regulatory system (based on total TEs and pH) and a risk‐based approach using 0.01 mol L–1 CaCl2 to estimate the bioavailable fraction. RESULTS: In total, 150 paired samples of Chinese flowering cabbages (Brassica parachinensis) and their growth soils were collected, and the total and extractable concentrations of chromium (Cr), cadmium (Cd), lead (Pb), nickel (Ni), copper (Cu), zinc (Zn), arsenic (As) and mercury (Hg), as well as soil pH and organic matter content, were measured. No more than 3.33% of the edible parts exceeded Chinese food safety standards, even when growing in soils exceeding the current regulatory thresholds by over 50%. The total soil Cd (1.5 mg kg−1), as well as the extractable concentrations of Cd (0.1 mg kg−1), Ni (0.03 mg kg−1) and Zn (0.1 mg kg−1), are the key factors affecting the TE concentrations in B. parachinensis. CONCLUSION: Our findings suggest that the current soil regulatory guidelines for safe production of B. parachinensis are overly strict and conservative. A risk‐based approach based on the extractable TE concentrations would provide a better indication for plant uptake of soil TEs and avoid the waste of farmlands that can still produce safe vegetables. Future research should focus on providing crop‐specific available TE concentration guidelines to promote effective utilization of farmlands. © 2021 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Radiotherapy is one of the most used treatment approaches for head and neck squamous cell carcinoma (HNSCC). Targeted inhibition of DNA repair machinery has the potential to improve treatment response by tailoring treatment to cancer cells lacking specific DNA repair pathways. Human papillomavirus (HPV)‐negative and HPV‐positive HNSCCs respond differently to radiotherapy treatment, suggesting that different approaches of DNA repair inhibition should be employed for these HNSCC groups. Here, we searched for optimal radiosensitization approaches for HPV‐positive and HPV‐negative HNSCCs by performing a targeted CRISPR‐Cas9 screen. We found that inhibition of base excision repair resulted in a better radiotherapy response in HPV‐positive HNSCC, which is correlated with upregulation of genes involved in base excision repair. In contrast, inhibition of nonhomologous end‐joining and mismatch repair showed strong effects in both HNSCC groups. We validated the screen results by combining radiotherapy with targeted inhibition of DNA repair in several preclinical models including primary and recurrent patient‐derived HNSCC xenografts. These findings underline the importance of stratifying HNSCC patients for combination treatments. What's new? The combination of radiotherapy and targeted inhibition of DNA repair pathways can potentially improve therapeutic response in patients with head and neck squamous cell carcinoma (HNSCC). Here, a targeted CRISPR‐Cas9 screen was used to identify optimal radiosensitization approaches for human papillomavirus (HPV)‐positive and HPV‐negative HNSCC. Inhibition of base excision repair was associated with improved radiotherapy response in HPV‐positive HNSCC cells. By comparison, inhibition of non‐homologous end‐joining and mismatch repair was effective in both HPV‐positive and HPV‐negative cells. The screen results were validated in patient‐derived xenograft models, suggesting that stratification of HNSCC patients by HPV status may benefit therapeutic outcome. [ABSTRACT FROM AUTHOR]

Eight new O‐alkyldithiophosphato nickel complexes 1–8 with chelating aminodiphosphine ligands have been successfully synthesized in moderate yields by the treatment of O,O′‐alkydithiophosphoric acid salts (R1O)2P{S}SH·Et2NH (R1 = CH3, CH2CH3) with nickel aminodiphosphine precursors Ni[(Ph2P)2NR2]Cl2 [R2 = (CH2)3OCH3, (CH2)3SCH3, (CH2)2CH(CH3)2, CH(CH3)C6H5] in the presence of Et3N at room temperature. Meanwhile, reactions of Ni(S2P{OR1}2)2 and aminodiphosphine ligands (Ph2P)2NR2 in CHCl3 solvents at room temperature also resulted in the formation of the target complexes 1–8 in satisfactory yields. The two synthetic routes are found to be efficient pathways to prepare O‐alkyldithiophosphato nickel complexes with chelating aminodiphosphine ligands. All the new complexes were fully characterized by elemental analysis, FTIR and NMR (1H, 13C, 31P) spectroscopy, and particularly for three of them by X‐ray crystallography. Moreover, these complexes were found to be catalysts for hydrogen production in the presence of a weak acid under electrochemical conditions. [ABSTRACT FROM AUTHOR]

In this paper, zinc phytate was prepared and used as a synergist in intumescent flame-retarded polypropylene composites. The results showed that the polypropylene composites with 17 wt% intumescent flame retardant and 2 wt% zinc phytate have a limiting oxygen index 29.2 and achieve the UL-94 V-0 rating. Moreover, the peak heat release rate of the polypropylene composites decreases from 374 to 275 kW/m2. Real-time Fourier-transform infrared spectroscopy showed that the zinc phytate delays the emission of carbon dioxide indicating that zinc phytate slows the degradation of polypropylene which regulates the suitability of intumescent flame-retardant system in polypropylene. [ABSTRACT FROM PUBLISHER]

Hirschsprung-associated enterocolitis (HAEC) is a life-threatening complication of Hirschsprung’s disease (HD). Although the pathological mechanisms are still unclear, studies have shown that HAEC has a close relationship with the disturbance of intestinal microbiota. This study aimed to investigate the characteristics of the intestinal microbiome of HD patients with or without enterocolitis. During routine or emergency surgery, we collected 35 intestinal content samples from five patients with HAEC and eight HD patients, including three HD patients with a history of enterocolitis who were in a HAEC remission (HAEC-R) phase. Using Illumina-MiSeq high-throughput sequencing, we sequenced the V4 region of bacterial 16S rRNA, and operational taxonomic units (OTUs) were defined by 97% sequence similarity. Principal coordinate analysis (PCoA) of weighted UniFrac distances was performed to evaluate the diversity of each intestinal microbiome sample. The microbiota differed significantly between the HD patients (characterized by the prevalence of Bacteroidetes) and HAEC patients (characterized by the prevalence of Proteobacteria), while the microbiota of the HAEC-R patients was more similar to that of the HAEC patients. We also observed that the specimens from different intestinal sites of each HD patient differed significantly, while the specimens from different intestinal sites of each HAEC and HAEC-R patient were more similar. In conclusion, the microbiome pattern of the HAEC-R patients was more similar to that of the HAEC patients than to that of the HD patients. The HD patients had a relatively distinct, more stable community than the HAEC and HAEC-R patients, suggesting that enterocolitis may either be caused by or result in a disruption of the patient’s uniquely adapted intestinal flora. The intestinal microbiota associated with enterocolitis may persist following symptom resolution and can be implicated in the symptom recurrence. [ABSTRACT FROM AUTHOR]

Ethanolamine spirocyclic pentaerythritol bisphosphonate (EMSPB), a novel intumescent flame retardant, was synthesized and used to improve the flame retardancy of rigid polyurethane foam (RPUF). The effects of EMSPB on the flammability, thermal stability, and mechanical properties of RPUF were discussed, respectively. Scanning electron microscopy (SEM) and compression strength tests showed that the EMSPB had favorable compatibility with the RPUF matrix and did not deteriorate the mechanical properties of the RPUF. Flammability of RPUF systems containing various contents of EMSPB was investigated by vertical burning test (UL-94) and limiting oxygen index (LOI) test. Results indicated that when the content of EMSPB was 25 wt%, the LOI of flame retardant RPUF could reach 27.5%, and a UL-94 V-0 rating was achieved. Thermogravimetric analysis showed that RPUF-containing EMSPB had a high yield of residual char at high temperatures, indicating that EMSPB was an effective charring agent. From the SEM observations of the residues of the flame retardant systems burned, the compact charred layers could be seen, which form protective shields to protect effectively the internal structure and inhibited the transmission of heat and heat diffusion during contacting fire. [ABSTRACT FROM AUTHOR]

The photochemical reaction of Fe2(S2)(CO)6 and Ph2CS affords the perthiolate Fe2(S3CPh2)(CO)6 ( 1) in good yield. As confirmed crystallographically, 1 contains a previously elusive perthiolate ligand. The related reaction of Fe2(S2)(CO)5(PPh3) and Ph2CS gave Fe2(S3CPh2)(CO)5(PPh3). Although Fe3S2(CO)9 and Ph2CS failed to efficiently give Fe2(S2CPh2)(CO)6, this compound could be prepared by desulfurization of 1 using PPh3. [ABSTRACT FROM AUTHOR]

Due to the large specific surface area and potential redox sites, metal organic frameworks (MOFs) are considered as a promising electrode material for supercapacitors. However, the low electrical conductivity of MOFs impedes their application in supercapacitors. Here, the NiCo-MOF/acetylene black composites were facily fabricated by an ultrasonic method, in which acetylene black was uniformly distributed between NiCo-MOF nanosheets and formed a conductive network, thus improving the electrical conductivity of NiCo-MOF as well as hindering their aggregation. The as-obtained NiCo-MOF/acetylene black composites exhibit high specific capacitance of 916.1 F g−1, remarkable rate capability and cycling stability compare to the pure NiCo-MOF. In addition, an asymmetrical supercapacitor were also constructed, which achieved a maximum energy density of 33.84 Wh kg−1 at a power density of 750 W kg−1 and good cycling stability with 85.25% of initial capacitance after 5000 cycles. The sheet-like NiCo-MOF/AB nanocomposite is synthesized via an ultrasonic method. The NiCo-MOF/AB composites exhibit a high specific capacitance of 916.1 F g−1 at 1 A g−1. The assembled asymmetric supercapacitors show high energy density of 33.84 Wh kg−1 with a power density of 750 W kg−1, and the capacitance retention remains 85.25% after 5000 cycles at 5 A g−1, indicating the excellent cycling stability. Unlabelled Image • NiCo-MOF/AB is facilely synthesized via an ultrasonic method. • NiCo-MOF/AB electrodes have a high capacitance of 916.1 F g−1 at 1 A g−1. • The asymmetrical supercapacitor shows maximum energy density of 33.84 Wh kg-1. • The capacity retention of supercapacitor device is 85.25% after 5000 cycles. [ABSTRACT FROM AUTHOR]

Mitochondrial DNA (mtDNA) mutations are frequent in cancer, yet their precise role in cancer progression remains debated. To functionally evaluate the impact of mtDNA variants on tumor growth and metastasis, we developed an enhanced cytoplasmic hybrid (cybrid) generation protocol and established isogenic human melanoma cybrid lines with wild-type mtDNA or pathogenic mtDNA mutations with partial or complete loss of mitochondrial oxidative function. Cybrids with homoplasmic levels of pathogenic mtDNA reliably established tumors despite dysfunctional oxidative phosphorylation. However, these mtDNA variants disrupted spontaneous metastasis from primary tumors and reduced the abundance of circulating tumor cells. Migration and invasion of tumor cells were reduced, indicating that entry into circulation is a bottleneck for metastasis amid mtDNA dysfunction. Pathogenic mtDNA did not inhibit organ colonization following intravenous injection. In heteroplasmic cybrid tumors, single-cell analyses revealed selection against pathogenic mtDNA during melanoma growth. Collectively, these findings experimentally demonstrate that functional mtDNA is favored during melanoma growth and supports metastatic entry into the blood.

Endothelial cells (ECs) grant access of disseminated cancer cells to distant organs. However, the molecular players regulating the activation of quiescent ECs at the premetastatic niche (PMN) remain elusive. Here, we find that ECs at the PMN coexpress tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and its cognate death receptor 5 (DR5). Unexpectedly, endothelial TRAIL interacts intracellularly with DR5 to prevent its signaling and preserve a quiescent vascular phenotype. In absence of endothelial TRAIL, DR5 activation induces EC death and nuclear factor κB/p38-dependent EC stickiness, compromising vascular integrity and promoting myeloid cell infiltration, breast cancer cell adhesion, and metastasis. Consistently, both down-regulation of endothelial TRAIL at the PMN by proangiogenic tumor-secreted factors and the presence of the endogenous TRAIL inhibitors decoy receptor 1 (DcR1) and DcR2 favor metastasis. This study discloses an intracrine mechanism whereby TRAIL blocks DR5 signaling in quiescent endothelia, acting as gatekeeper of the vascular barrier that is corrupted by the tumor during cancer cell dissemination.

Meningiomas are the most common benign brain tumors. Mutations of the E3 ubiquitin ligase TRAF7 occur in 25% of meningiomas and commonly cooccur with mutations in KLF4, yet the functional link between TRAF7 and KLF4 mutations remains unclear. By generating an in vitro meningioma model derived from primary meningeal cells, we elucidated the cooperative interactions that promote meningioma development. By integrating TRAF7-driven ubiquitinome and proteome alterations in meningeal cells and the TRAF7 interactome, we identified TRAF7 as a proteostatic regulator of RAS-related small GTPases. Meningioma-associated TRAF7 mutations disrupted either its catalytic activity or its interaction with RAS GTPases. TRAF7 loss in meningeal cells altered actin dynamics and promoted anchorage-independent growth by inducing CDC42 and RAS signaling. TRAF deficiency-driven activation of the RAS/MAPK pathway promoted KLF4-dependent transcription that led to upregulation of the tumor-suppressive Semaphorin pathway, a negative regulator of small GTPases. KLF4 loss of function disrupted this negative feedback loop and enhanced mutant TRAF7-mediated cell transformation. Overall, this study provides new mechanistic insights into meningioma development, which could lead to novel treatment strategies. SIGNIFICANCE: The intricate molecular cross-talk between the ubiquitin ligase TRAF7 and the transcription factor KLF4 provides a first step toward the identification of new therapies for patients with meningioma., (©2021 American Association for Cancer Research.)

Loss of chromosome 9p21 is observed in one-thirds of clear-cell renal cell carcinoma (ccRCC) and is associated with poorer patient survival. Unexpectedly, 9p21 LOH does not lead to decreased expression of the 9p21 tumor suppressor genes, CDKN2A and CDKN2B , suggesting alternative mechanisms of 9p-mediated tumorigenesis. Concordantly, CRISPR-mediated 9p21 deletion promotes growth of immortalized human embryonic kidney epithelial cells independently of the CDKN2A/B pathway inactivation. The 9p21 locus has a highly accessible chromatin structure, suggesting that 9p21 loss might contribute to kidney cancer progression by dysregulating genes distal to the 9p21 locus. We identified several 9p21 regulatory hubs by assessing which of the 9p21-interacting genes are dysregulated in 9p21-deleted kidney cells and ccRCCs. By focusing on the analysis of the homeobox gene 13 ( HOXB13 ) locus, we found that 9p21 loss relieves the HOXB13 locus, decreasing HOXB13 methylation and promoting its expression. Upregulation of HOXB13 facilitates cell growth and is associated with poorer survival of patients with ccRCC. IMPLICATIONS: The results of our study propose a novel tumor suppressive mechanism on the basis of coordinated expression of physically associated genes, providing a better understanding of the role of chromosomal deletions in cancer., (©2021 American Association for Cancer Research.)

The title complex, [Fe2(C8H12S3)(CO)6] or [{Fe(CO)3}2(μ-L)] [L = 3,3-dimethyl-4-(propan-2-yl-idene)thietane-2,2-bis-(thiol-ato)], consists of two Fe(CO)3 moieties double-bridged by a di-thiol-ate ligand. Each of the two Fe(I) atoms has a distorted anti-prismatic coordination environment consisting of three carbonyl groups, two S atoms of the di-thiol-ate ligand and the neighboring Fe(I) atom [Fe-Fe = 2.4921 (4) Å]. Weak C-H⋯O inter-molecular inter-actions result in the formation of dimers. This is the second crystal structure reported with the 3,3-dimethyl-4-(propan-2-yl-idene)thietane-2,2-bis-(thiol-ate) ligand and the first in which it bridges two metal atoms.