Land subsidence has become a widespread engineering geological problem due to human-induced causes such as the withdrawal of groundwater and the extraction of coal and ores. There is a relative lack ...of research on land subsidence under the coupling effect of groundwater and coal mining. This paper uses numerical and theoretical computational models to study land subsidence under the coupling effect of groundwater and coal mining. The study area is a coal mine in Jining City from 2000 to 2020. Numerical results show that groundwater withdrawal induces substantial land subsidence over a long period and that the rate of land subsidence decreases over time. The maximum land subsidence was 128 mm in 2010. Due to coal extraction (2015), the area induces significant land subsidence in the short term. The maximum land subsidence in 2016 was 305 mm. Based on the stochastic medium theory, this paper establishes a theoretical model for land subsidence under the coupling effect of groundwater and coal mining. And based on the numerical results, the theoretical subsidence equation applicable to the area is calculated. By comparing the theoretical results with the actual measurement results, the analysis proves that the equation can better calculate the land subsidence of the model.
This study investigated the effects of thermal pretreatment and ex-situ grinding on the production of bio-oil and biochar from the pyrolysis of mallee wood cylinders in a fluidised-bed reactor. The ...wood cylinders were firstly pretreated at 150–380°C and were then crushed into small particles before further pyrolysis at 500°C. Thermal pretreatment alone for wood cylinders could not promote the bio-oil yield. Combined thermal pretreatment at low temperatures and subsequent grinding facilitated the formation of bio-oil and minimised the formation of biochar. This is because the thermal pretreatment and grinding partially destroyed the cell wall structure and improved the mass transfer of volatiles exiting from the particles during the subsequent pyrolysis. However, if the pretreatment temperature was above 260°C, the biochar yields increased due to the cross-linking and charring reactions. These charring reactions compromised the beneficial effects of grinding, leading to decreases in the formation of bio-oil. The balance between thermal pretreatment and grinding needed to be delicately managed to maximise the formation of bio-oil. The pretreatment temperature would significantly affect the composition of bio-oil from the ex-situ grinding pyrolysis. The controlled pretreatment temperature could somewhat “activate” lignin or cause cross-linked bonds in biomass which was responsible for the formation of aromatics.
•Effects of thermal treatment and grinding on pyrolysis of wood cylinders were studied.•The bio-oil yield was not promoted by the thermal treatment of wood cylinders.•Low temperature treatment with ex-situ grinding greatly promoted bio-oil formation.•High temperature treatment compromised beneficial effects of grinding on bio-oil yield.•Balance between pretreatment and grinding was responsible for the bio-oil formation.
Beclin 1 is a well-established core mammalian autophagy protein that is embryonically indispensable and has been presumed to suppress oncogenesis via an autophagy-mediated mechanism. Here, we show ...that Beclin 1 is a prenatal primary cytoplasmic protein but rapidly relocated into the nucleus during postnatal development in mice. Surprisingly, deletion of beclin1 in in vitro human cells did not block an autophagy response, but attenuated the expression of several DNA double-strand break (DSB) repair proteins and formation of repair complexes, and reduced an ability to repair DNA in the cells exposed to ionizing radiation (IR). Overexpressing Beclin 1 improved the repair of IR-induced DSB, but did not restore an autophagy response in cells lacking autophagy gene Atg7, suggesting that Beclin 1 may regulate DSB repair independent of autophagy in the cells exposed to IR. Indeed, we found that Beclin 1 could directly interact with DNA topoisomerase IIβ and was recruited to the DSB sites by the interaction. These findings reveal a novel function of Beclin 1 in regulation of DNA damage repair independent of its role in autophagy particularly when the cells are under radiation insult.
Context
A variety of factors have been linked to the occurrence of anterior cruciate ligament injury (ACLI), including sex, familial factors, and genetic variations.
Objective
To find the genetic ...loci associated with ACLI and explore the genetic mechanism of ACLI in order to provide a genetic basis for the diagnosis, prognosis, and treatment of patients with ACLI.
Design
Cross-sectional study.
Setting
Hospital.
Patients or Other Participants
Data from 101 Chinese Yunnan Han patients with ACLI and 110 Yunnan Han individuals without ACLI (control group) were collected.
Main Outcome Measure(s)
The single nucleotide polymorphisms of COL1A1 rs1800012, COL5A1 rs12722 and rs13946, COL12A1 rs970547 and rs240736 and the rs1800787, rs1800788, rs1800789, rs1800790, rs1800791, and rs2227389 in the β-fibrinogen (β-fib) promoter region were analyzed using restriction fragment length polymorphism and DNA sequencing detection, and their genetic associations with ACLI were assessed.
Results
Single nucleotide polymorphisms of COL1A1 rs1800012, COL5A1 rs12722 and rs13946, and the rs1800789 and rs1800791 in the β-fib promoter region showed no difference between patients with ACLI and control participants, but the changes of COL12A1 rs970547 and rs240736 and the rs1800787, rs1800788, rs1800790, and rs2227389 genotypes in the β-fib promoter region were associated with ACLI. Furthermore, the rs970547 allele and genotype frequencies in male ACLI patients were different from the control group (P < .05): the frequencies of the rs970547 A and G alleles in the patients were 71.9% and 28.1%, respectively, and in the control group were 58.8% and 41.2%, respectively. The frequencies of AA, AG, and GG genotypes in the patients were 49.3%, 45.2%, and 5.5%, respectively, and in the control group were 27.5%, 62.7%, and 9.8%, respectively, suggesting that male carriers of rs970547 A and rs970547 AA were at high risk of ACLI.
Conclusions
Males with the rs970547 A allele and rs970547 AA genotype of COL12A1 may be at high risk for ACLI. Low rs1800787 TT and high rs1800788 CT, rs1800790 AG, and rs2227389 CT frequencies as well as high TGA* of rs1800790, rs1800791, and rs2227389 in the β-fib promoter region may be genetic risk factors related to ACLI.
Hot melt adhesives have been broadly applied in vehicles, electronics, and packaging industries due to their excellent properties of no-pollution, easy-peeling, and little damage to the substrate ...surface. However, the weak adhesion strength and poor reusability of hot melt adhesives prepared from traditional diglycidyl ether of bisphenol A (DGEBA) greatly hindered their application. Herein, we synthesized a hyperbranched epoxy resin (MHER) by a highly efficient microwave-assisted reaction and constructed a super-strong reusable thermoplastic hot melt adhesive (HEA) through incorporation with DGEBA and a polyether amine bearing the ureidopyrimidinone motif, without the use of any solvent. The synthesis efficiency of MHER was increased about 6.3 times and the tedious process was simplified remarkably. The mechanical properties of the prepared HEA were enhanced by the incorporation of MHER, with the best performance obtained at 8 wt% MHER in HEA (HEA-8). Compared with the hot melt adhesive without MHER (HEA-0), the adhesion strength, tensile strength, and tensile toughness of HEA-8 attached to a stainless steel substrate were enhanced by 27.4%, 78.1%, and 475.0%, respectively. HEA-8 showed a super-high adhesion strength of approximately 10.7 MPa and outstanding reusability with >82% adhesion strength retained after five cycles. The reusability was attributed to the cleavage and formation of dynamic noncovalent quadruple hydrogen bond interactions. It is highly expected that this work will provide a facile green strategy for preparing hot melt adhesives with excellent adhesion and reusability.
The hyperbranched epoxy hot melt adhesive (HEA-8) showed a super-high adhesion strength of approximately 10.7 MPa and outstanding reusability with >82% adhesion strength retained after five cycles.
Nonconcentric reduction of hip posterior dislocation caused by the acetabular labrum rim fracture is rare. There has been very little study on the feasibility of arthroscopically treatment and medium ...and mid-term evaluation to this pathology. The objectives of the current study were: (1) Is the arthroscopically assisted technique feasible to this manage this injury? (2) What is the effectiveness of arthroscopic treatment for nonconcentric reduction of hip posterior dislocation caused by acetabular labrum rim fracture.
Arthroscopically assisted procedure is an alternative treatment modality for nonconcentric reduction of hip posterior dislocation caused by acetabular labrum rim fracture.
Thirteen of 257 posterior hip dislocations who were admitted to our hospital from February 2008 to March 2017 were included: 9 males and 4 females, with an average age of 23.7 (15–36) years. All of them underwent hip posterior dislocation and nonconcentric reduction related to acetabular labrum rim fracture. All of them had arthroscopic reduction and fixation of the rim fracture. Visual Analogic Score (VAS) score, modified Harris score, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score and the last follow-up radiographs were analyzed respectively. Postoperative complication and the need for secondary operation were recorded during the process.
The incidence rate of this pathology was nearly 5%. Twelve out of 13 patients were followed up for an average of 42 (range, 26–68) months. At the final follow-up, VAS score was decreased from 5.2±0.9 (range, 4.0–6.1) preoperatively to 0.5±0.5 (range, 0.0–1.0) (p<0.0001), modified Harris score and WOMAC score were increased statistically significant from 32±8 (range, 28–40) and 30±5 (range, 25–35) to 94±5 (range, 89–99) and 95±4 (range, 91–99) respectively (p<0.0001). All patients have had completely concentric reduction and returned to activities of daily life. There was not any hip arthroscopic complication such as sciatic nerve injury and intra-abdominal fluid extravasation. Besides, there were no aseptic necrosis and revision case.
Arthroscopically assisted procedure is an alternative treatment modality for nonconcentric reduction of hip posterior dislocation caused by the acetabular labrum rim fracture without surgical dislocation procedure. Good clinical results can be achieved without any complications related to the surgical procedure.
Level IV, therapeutic case series.
A versatile strategy for smart fluorescent materials is lacking due to their diverse responding mechanisms and incompatibility of responsive behaviors. Herein an adaptable strategy is presented ...toward a multi‐stimuli‐responsive fluorescent material with stage‐by‐stage responsive behavior by blending linear polymers modified with different stimulus‐responsive moieties and AIE cross‐linker. Under stimuli, the linear polymer can cross‐link with the cross‐linker to form networks, which intrinsically restrict the intramolecular rotation of the AIE molecule to induce strong emission. A unified stimuli‐responsive mechanism is involved in that various stimuli are transferred through the organized “stimulus‐crosslink‐emission” process. This strategy ensures the compatibility of different stimuli‐responses and the adjustability of stimulus‐response behavioral logic. These multi‐stimuli‐responsive fluorescent materials exhibited strong accessibility and adaptability for information encryption.
An adaptable strategy toward a multi‐stimuli‐responsive fluorescent material with stage‐by‐stage responsive behavior was developed. This strategy ensures the compatibility of different stimuli‐responses and the adjustability of stimulus‐response behavioral logic. These multi‐stimuli‐responsive fluorescent materials exhibited strong accessibility and adaptability for information encryption.
Abstract
The application of hydrogels often suffers from their inherent limitation of poor mechanical properties. Here, a carboxyl‐functionalized and acryloyl‐terminated hyperbranched ...polycaprolactone (PCL) was synthesized and used as a macro‐cross‐linker to fabricate a super strong and ultra‐tough ionic hydrogel. The terminal acryloyl groups of hyperbranched PCL are chemically incorporated into the network to form covalent cross‐links, which contribute to robust networks. Meanwhile, the hydrophobic domains formed by the spontaneous aggregation of PCL chains and coordination bonds between Fe
3+
and COO
−
groups serve as dynamic non‐covalent cross‐links, which enhance the energy dissipation ability. Especially, the influence of the hyperbranched topological structure of PCL on hydrogel properties has been well investigated, exhibiting superior strengthening and toughening effects compared to the linear one. Moreover, the hyperbranched PCL cross‐linker also endowed the ionic hydrogel with higher sensitivity than the linear one when used as a strain sensor. As a result, this well‐designed ionic hydrogel possesses high mechanical strength, superior toughness, and well ionic conductivity, exhibiting potential applications in the field of flexible strain sensors.
Higher-order exceptional points (EPs), which appear as multifold degeneracies in the spectra of non-Hermitian systems, are garnering extensive attention in various multidisciplinary fields. However, ...constructing higher-order EPs still remains a challenge due to the strict requirement of the system symmetries. Here we demonstrate that higher-order EPs can be judiciously fabricated in parity–time (
PT
)-symmetric staggered rhombic lattices by introducing not only on-site gain/loss but also non-Hermitian couplings. Zero-energy flatbands persist and symmetry-protected third-order EPs (EP3s) arise in these systems owing to the non-Hermitian chiral/sublattice symmetry, but distinct phase transitions and propagation dynamics occur. Specifically, the EP3 arises at the Brillouin zone (BZ) boundary in the presence of on-site gain/loss. The single-site excitations display an exponential power increase in the
PT
-broken phase. Meanwhile, a nearly flatband sustains when a small lattice perturbation is applied. For the lattices with non-Hermitian couplings, however, the EP3 appears at the BZ center. Quite remarkably, our analysis unveils a dynamical delocalization-localization transition for the excitation of the dispersive bands and a quartic power increase beyond the EP3. Our scheme provides a new platform toward the investigation of the higher-order EPs and can be further extended to the study of topological phase transitions or nonlinear processes associated with higher-order EPs.
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