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Poly(butylene adipate-terephthalate) (PBAT), as one of the most common and promising biodegradable plastics, has been widely used in agriculture, packaging, and other industries due to its strong biodegradability properties. It is well known that PBAT suffers a series of natural weathering, mechanical wear, hydrolysis, photochemical transformation, and other abiotic degradation processes before being biodegraded. Therefore, it is particularly important to understand the role of abiotic degradation in the life cycle of PBAT. Since the abiotic degradation of PBAT has not been systematically summarized, this review aims to summarize the mechanisms and main factors of the three major abiotic degradation pathways (hydrolysis, photochemical transformation, and thermochemical degradation) of PBAT. It was found that all of them preferentially destroy the chemical bonds with higher energy (especially C-O and C=O) of PBAT, which eventually leads to the shortening of the polymer chain and then leads to reduction in molecular weight. The main factors affecting these abiotic degradations are closely related to the energy or PBAT structure. These findings provide important theoretical and practical guidance for identifying effective methods for PBAT waste management and proposing advanced schemes to regulate the degradation rate of PBAT.

Supplemental Digital Content is Available in the Text.Tachyarrhythmias after cardiac surgery is a common occurrence in clinical practice, which can be life threatening. We searched 6 databases, including Embase, PubMed, Cochrane, CNKI, Wanfang, and Sinomed, to evaluate the effect of dexmedetomidine on tachyarrhythmias after adult cardiac surgery. The primary end point was the number of patients with atrial fibrillation (AF) after cardiac surgery. The secondary end points included the number of patients with supraventricular tachycardia or with ventricular tachycardia or with ventricular fibrillation or with myocardial infarction or deceased patients, the duration of mechanical ventilation, the intensive care unit stay, hospital stay, and the number of patients with bradycardia and those with hypotension. Among the 1388 retrieved studies, 18 studies (n = 3171 participants) met our inclusion criteria. Dexmedetomidine reduced the incidence of AF by 17% [relative risk (RR) = 0.83; 95% confidence interval (CI), 0.73–0.93; P= 0.002]. Through subgroup analysis, we found that when the maintenance dose of dexmedetomidine was >0.7 µg·kg−1·h−1, the effect of preventing AF was obvious (RR = 0.58; 95%CI 0.43–0.78; P= 0.0003). Dexmedetomidine also reduced the incidence of supraventricular tachycardia by approximately 70% (RR = 0.29; 95% CI, 0.11–0.77; P= 0.01) and the incidence of ventricular tachycardia by approximately 80% (RR = 0.23; 95% CI, 0.08–0.63; P= 0.004) but had no effect on ventricular fibrillation (RR = 1.02; 95% CI, 0.14–7.31; P= 0.99). The major side effect of dexmedetomidine was bradycardia. Dexmedetomidine can reduce the incidence of AF (especially high dosages), supraventricular tachycardia, and ventricular tachycardia after cardiac surgery in adults, but it does not affect the occurrence of ventricular fibrillation.

Hybrid perovskite photodetectors generally exhibit brilliant performance for photodetecting in the visible spectrum but poor detectability in the solar-blind ultraviolet (UV) region. To break through the bottleneck, we demonstrate a novel strategy to broaden the spectral response of perovskite photodetectors to the solar-blind UV region through phosphor encapsulation. The high photoluminescence quantum yield trichromatic phosphor capping layer achieves an extended spectral response to the solar-blind UV region through effectively down-converting the incident UV light into visible light. In addition, an external quantum efficiency of up to 12.13%@265 nm is achieved without bias voltage, while the initial value is near zero. The corresponding spectral responsivity and detectivity are 0.0269 A/W and 7.52 × 1011Jones, respectively. Thus, the photodetectors show a high photocurrent and on/off ratio, increasing by roughly 2 orders of magnitude. Moreover, the photodetectors exhibit a large linear dynamic range of 105 dB, fast response times of 50.16/51.99 μs, and excellent stability. The practical applications for flame detection and UV-based communication are further explored. This work provides a new way to achieve UV light detection based on perovskite photodetectors. Perhaps, it may also be a promising alternative for wide-band gap semiconductors to realize the urgent pursuit of UV detection.

Background Oxidative stress plays crucial roles in the pathogenesis of chronic rhinosinusitis with nasal polyps (CRSwNP). Thioredoxin-interacting protein (TXNIP) is essential in the process of triggering oxidative stress. However, its role and mechanism in CRSwNP remain unclear. The present study sought to explore the role and mechanism of TXNIP in the pathogenesis of CRSwNP.Methods Western blotting, real-time PCR and immunohistochemistry (IHC) were employed to assess TXNIP, thioredoxin (TRX) expression in nasal tissue samples from patients with CRSwNP and control subjects. MDA level and SOD activity in nasal tissue homogenates were measured using MDA and SOD Assay Kit. To evaluate the role and mechanism of TXNIP in CRSwNP, human nasal epithelial cells (HNECs) were cultured and stimulated using TXNIP siRNA, with or without N-acetylcysteine (NAC, an ROS scavenger). Western blotting, real-time PCR, ROS detecting dye DCFH-DA, MDA and SOD Assay Kit were performed to assess the effects and mechanisms of stimulators on the cells.Results We found significantly increased levels of TXNIP and decreased levels of TRX protein, mRNA, positive cells, increased MDA level and decreased SOD activity in CRSwNP patients compared with control subjects. In vitro study, significantly altered levels of TXNIP, TRX, MDA, SOD and ROS in HNECs were found following treatment of TXNIP siRNA with or without NAC on HNECs.Conclusion TXNIP expression was increased and TRX expression was decreased in CRSwNP at both protein and mRNA levels. MDA levels were increased and SOD activities were decreased in CRSwNP. TXNIP may have negative association with TRX, and then decrease SOD activities and increase MDA levels, resulting in the upregulation of ROS and oxidative stress in HNECs, which may play a pivotal role in the pathogenesis of CRSwNP. Future studies are expected to further explore the role and mechanism of TXNIP in CRSwNP.

Background/Aims:human endogenous retrovirus-H long terminal repeat-associating protein 2 (HHLA2) is highly expressed in multiple solid malignant tumors, making it a potential biomarker for tumorigenesis and invasion. However, the expression and clinical significance of HHLA2 in bladder urothelial carcinoma (BUC) have not been extensively studied. This study aimed to investigate the relationship between HHLA2 expression and clinicopathological characteristics of BUC. Methods:A total of 212 patients pathologically diagnosed with BUC were included in this study. HHLA2 expression was analyzed by immunohistochemical staining and qRT-polymerase chain reaction. Correlations of HHLA2 expression and pathological characteristics, including 5-year recurrence-free survival (RFS) and overall survival (OS) were examined, and the diagnostic value of HHLA2 was estimated by using the receiver operating characteristic (ROC) curve. Results:Immunohistochemical staining showed that the expression of HHLA2 was significantly upregulated in BUC tissues compared with normal bladder tissues. In BUC tissues, HHLA2 expression was significantly associated with tumor size, tumor stage, tumor grade, and lymph node metastasis (all p< 0.05). HHLA2 expression was an independent prognostic factor of tumor metastasis (p< 0.05). The Kaplan-Meier survival curve revealed that high HHLA2 expression was significantly correlated with the poor RFS and OS of BUC patients (both p< 0.05), and the ROC curve showed HHLA2 could be a good diagnostic marker. Conclusions:HHLA2 can independently predict unfavorable prognosis in BUC.

All-inorganic CsPbBr3perovskite solar cells (PSCs) have attracted tremendous attentions in the photovoltaic field these days in view of their outstanding stability, especially thermal stability. However, the bromide-rich perovskite, such as CsPbBr3, always suffer from a low phase-purity and poor morphology synthesized by traditional two-step deposition route. Herein, we demonstrate a facile multistep spin-coating strategy to fabricate high-quality CsPbBr3films on the low-temperature processed compact TiO2(c-TiO2) electron transport layer (ETL) of the carbon-based PSCs. As-prepared films exhibit more homogeneous with higher CsPbBr3-phase purity and larger average grain sizes up to 1 µm, compared to those prepared through traditional two-step deposition process. The champion power conversion efficiency (PCE) of the planar CsPbBr3PSC is boosted from 7.05% to 8.12%, getting an increase by 15.2%, due to the increased crystallinity and light-harvesting ability as well as reduced trap states of the CsPbBr3film. To further enhance the device performance, a SnO2thin layer with much higher carrier mobility than TiO2is introduced to passivate the c-TiO2ETL. It is found that the SnO2layer can not only improve the surface morphology of the ETL, but also reduce the current shunting pathways in the c-TiO2. The TiO2/SnO2bilayered ETL possesses a superior electron extraction capability, beneficial to the charge transport and suppression of the interfacial trap-assisted recombination. The best-performing TiO2/SnO2-based CsPbBr3PSC delivers an excellent fill factor of 0.817 and a high PCE of 8.79%, which is the highest efficiency for planar CsPbBr3PSCs reported to date. More importantly, the unencapsulated all-inorganic PSCs show a promising humidity and thermal stability with no decline in efficiency when stored in ambient air at room temperature (25 °C) for over 1000 h and 60 °C for one month, respectively. Our work pave the ways for practical applications of cost-effective, highly efficient and stable all-inorganic PSCs.

Neonatal hyperbilirubinemia leads to neural dysfunction, including sensorineural hearing loss. Our previous studies demonstrated that elevated bilirubin induced apoptotic pathway activation and led to cell malformation in spiral ganglion neurons of neonatal rat cochlear organotypic explants. However, the underlying mechanisms remained unclear. Concurrent hyperbilirubinemia and acidemia would exacerbate neuronal damage. Acid-sensing ion channels (ASICs), which belong to the epithelial Na+channel/degenerin (ENaC/DEG) superfamily, were activated during acidic pH fluctuations. To elucidate the roles of ASICs in bilirubin-induced ototoxicity, we treated postnatal cochlear explants of Sprague-Dawley rats with ASIC blockers and characterized the morphological and molecular alterations. Briefly, the basilar membrane and spiral ganglion neurons of the Sprague-Dawley rats at postnatal day 3 were cultured. The organotypic explants were randomly divided into control, bilirubin only, and bilirubin with ASIC blocker treatment groups. After 24 hours of culture, samples were taken for morphological molecular analysis. Our results showed that bilirubin-induced ototoxicity was alleviated in the alkalized environment and blocking ASIC1a protected cochleae from bilirubin-induced apoptosis. Transcriptomic analysis indicated that the profiles in ASIC1a blocker-treated group were similar to those in the control group, compared with the bilirubin-only treated cochleae group. The inhibition of ASIC1a suggests a potential attenuation of bilirubin-induced SGN degeneration, possibly through regulation of the MAPK signaling pathway. Taken together, our findings suggest that inhibiting ASIC1a alleviated bilirubin-induced ototoxicity in cochlear explants, with the protective effects being mediated, at least partially, via the MAPK signaling pathway. These findings shed light on the potential therapeutic targets for treating bilirubin-induced ototoxicity.

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Organometal trihalide perovskite solar cells (PSCs) with carbon counter electrode (CE) have attracted tremendous interest due to their remarkable properties such as low cost and high stability. However, carbon-based PSCs always suffer from much lower power conversion efficiency (PCE) than the counterparts with noble metal cathode. Herein, we demonstrate a carbon-based planar heterojunction PSC using high-crystallinity Ni-doped rutile TiO2as electron transport layer (ETL) for the first time, while copper phthalocyanine (CuPc) is introduced as hole transport layer (HTL). It is found that Ni doping can shift the Fermi level of the ETL upward and increase the charge mobility of the TiO2film, thus enhancing the charge transport and extraction. An optimized PCE of 17.46% was obtained after 0.01 M Ni doping, comparable to or even better than devices with state-of-the-art doped Spiro-OMeTAD as HTL and Au as CE. To the best of our knowledge, this is the highest efficiency that has been reported for carbon-based PSCs. By contrast, the pristine TiO2-based device only displayed a PCE of 15.82%. Detailed superior capability of Ni-doped TiO2in facilitating charge transfer and suppressing carrier recombination are revealed by Hall effect and photoluminescence (PL) as well as electrochemical impedance spectroscopy (EIS) measurements. Furthermore, the use of highly stable CuPc and commercial carbon makes as-prepared PSCs exhibit excellent stability with no obvious decline in PCE after being stored in ambient air for 1200 h. This work presents an important step forwards to the commercialization of carbon-based PSCs with high efficiency and long-term stability.

Metal halide perovskite solar cells (PSCs) have attracted extensive research interest for next-generation solution-processed photovoltaic devices because of their high solar-to-electric power conversion efficiency (PCE) and low fabrication cost. Although the world’s best PSC successfully achieves a considerable PCE of over 20% within a very limited timeframe after intensive efforts, the stability, high cost, and up-scaling of PSCs still remain issues. Recently, inorganic perovskite material, CsPbBr3, is emerging as a promising photo-sensitizer with excellent durability and thermal stability, but the efficiency is still embarrassing. In this work, we intend to address these issues by exploiting CsPbBr3as light absorber, accompanied by using Cu-phthalocyanine (CuPc) as hole transport material (HTM) and carbon as counter electrode. The optimal device acquires a decent PCE of 6.21%, over 60% higher than those of the HTM-free devices. The systematic characterization and analysis reveal a more effective charge transfer process and a suppressed charge recombination in PSCs after introducing CuPc as hole transfer layer. More importantly, our devices exhibit an outstanding durability and a promising thermal stability, making it rather meaningful in future fabrication and application of PSCs.

The Enterococcus hirae CopB ATPase (EC 3.6.1.3) confers copper resistance to the organism by expelling excess copper. Two related human ATPase genes, ATP7A (EC 3.6.1.36) and ATP7B (EC 3.6.1.36), have been cloned as the loci of mutations causing Menkes and Wilson diseases, diseases of copper metabolism. Many mutations in these genes have been identified in patients. Since it has not yet been possible to purify the human copper ATPases, it has proved difficult to test the impact of mutations on ATPase function. Some mutations occur in highly conserved sequence motifs, suggesting that their effect on function can be tested with a homologous enzyme. Here, we used the E. hirae CopB ATPase to investigate the impact of such mutations on enzyme function in vivo and in vitro. The Menkes disease mutation of Cys-1000 → Arg, changing the conserved Cys-Pro-Cys (‘CPC’) motif, was mimicked in CopB. The corresponding Cys-396 → Ser CopB ATPase was unable to restore copper resistance in a CopB knock-out mutant in vivo. The purified mutant ATPase still formed an acylphosphate intermediate, but possessed no detectable ATP hydrolytic activity. The most frequent Wilson disease mutation, His-1069 → Gln, was introduced into CopB as His-480 → Gln (H480Q). This mutant CopB also failed to confer copper resistance to a CopB knock-out strain. Purified H480Q CopB formed an acylphosphate intermediate and retained a small, but significant, ATPase activity. Our results reveal that Cys-396 and His-480 of CopB are key residues for ATPase function, and similar roles are suggested for Cys-1000 and His-1069 of Menkes and Wilson ATPases respectively.

The Enterococcus hirae ATPase CopA is a member of the recently discovered heavy metal ATPases and shares 43% sequence identity with the human Menkes and Wilson copper ATPases. To study CopA biochemically, it was overexpressed in E. coli with an N-terminal histidine tag and purified to homogeneity by nickel affinity chromatography. The purified CopA catalyzed ATP hydrolysis with a Vmax of 0.15 μmol/min/mg and a Km for ATP of 0.2 mM and had an optimum pH of 6.25. The activity was 3- to 4-fold stimulated by reconstitution into proteoliposomes. The enzyme formed an acylphosphate intermediate. Its kinetics of formation and the effects of inhibitors and metal ions upon it support a function of CopA in copper transport. Purification and functional reconstitution of CopA provides the basis to study copper transport in vitro.

The copoperon of Enterococcus hiraeencodes a repressor, CopY, a copper chaperone, CopZ, and two copper ATPases, CopA and CopB. Regulation of the copoperon is bi-phasic, with copper addition as well as copper chelation leading to induction. Using a plasmid-borne system with a reporter gene, induction of wild-type and mutant coppromoters by high and low copper conditions was investigated. Only mutations that impaired the interaction of CopY with both DNA binding sites had a marked effect on regulation, leading to hyperinduction by copper(I) or copper(II). Chelation of copper(II), but not copper(I), also induced the operon, but induction by copper chelation was not significantly affected by the mutations. E. hiraemutants with reduced extracellular copper reductase activity exhibited the same induction kinetics as wild-type cells. These results show that copper addition and copper chelation induce the copoperon by different routes.

Researchers have focused on perovskite-based ultraviolet photodetectors due to their significance in fundamental scientific and practical applications. However, toxicity and instability hold back their mass production and commercialization. The lead-free Cs2AgBiBr6double perovskite, promised to be an alternative, is fabricated mostly by spin coating, which restricts the practical application in high-resolution image sensors. Herein, we demonstrate a sequential vacuum evaporation method for the fabrication of the Cs2AgBiBr6film. A self-powered ultraviolet photodetector based on the evaporated Cs2AgBiBr6thin film is further constructed without any carrier-transport layers, for the first time. The best-performing device has a high on/off ratio of 6.6 × 103, and its response time is fast, less than 6.13 μs. Moreover, the as-prepared devices exhibit salient stability under harsh operational conditions (continuous illumination, high temperature, and humidity). In addition, the pixelated image sensor containing a 25 × 25 Cs2AgBiBr6photodetector array achieves a proof-of-concept special pattern recognition. Our work paves the way for new-generation ultraviolet image sensors composed of environmentally friendly and high-performance perovskite photodetector arrays.