Synthesis and Characterization of Boronate Affinity Three-Dimensionally Ordered Macroporous Materials.

Sample pretreatment is a key step for qualitative and quantitative analysis of trace substances in complex samples. Cis-dihydroxyl (cis-diol) group-containing substances exist widely in biological samples and can be selectively bound by boronate affinity adsorbents. Based on this, in this article, we proposed a simple method for the preparation of novel spherical three-dimensionally ordered macropore (3DOM) materials based on a combination of the boronate affinity technique and colloidal crystal template method. The prepared 3DOM materials were characterized using Fourier transform-infrared spectroscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, and thermo-gravimetric analysis, and results showed that they possessed the characteristics of a high specific surface area, high porosity, and more boronic acid recognition sites. The adsorption performance evaluation results showed that the maximum adsorption capacity of the boron affinity 3DOMs on ovalbumin (OVA) could reach to 438.79 mg/g. Kinetic and isothermal adsorption experiments indicated that the boronate affinity 3DOM material exhibited a high affinity and selectivity towards OVA and adenosine. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of the proteins in egg whites was conducted and proved that the glycoprotein in the egg whites could be separated and enriched with a good performance. Therefore, a novel boronate affinity 3DOM material a with highly ordered and interconnected pore structure was prepared and could be applied in the separation and enrichment of molecules with cis-diol groups from complex samples with a good selectivity, efficiency, and high throughput.

Malignancy is increased in patients with antineutrophil cytoplasmic antibody-associated vasculitis in China.

OBJECTIVE: It has been reported that in western countries malignancy risk was higher in patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) compared with that in the general population. In the current study, we investigated the incidence, spectrum and risk factors of malignancy in Chinese AAV patients. METHODS: AAV patients diagnosed from 1995 to 2021 in Peking University First Hospital with a follow-up more than 12 months were recruited. Standardized incidence ratios (SIR) were calculated to describe the risk of malignancy, adjusted for sex, age and follow-up time. RESULTS: A total of 552 AAV patients were recruited, among which 23 patients had malignancies either preceding or concurrent with AAV diagnosis, and 43 of the remaining 529 patients developed malignancies within 4.3 ± 4.2 years post AAV diagnosis (SIR: 2.24; 95% CI: 1.68-2.99; p < 0.001). Among these 66 patients, twenty different sites of malignancy were observed, lung cancer being most frequent. To get exactly expected malignancies for the calculation of SIR, 529 patients without preceding or concurrent malignancies were included in the following analysis. Lung cancer was still the leading malignancy diagnosis (SIR: 5.01; 95% CI: 3.29-7.62), followed by malignancies in the kidney, bladder, ureter and prostate. Male gender (HR:2.84; 95%CI:1.36-5.96; p = 0.006) and older age (per year, HR:1.04; 95%CI:1.00-1.07; p = 0.038) were significantly associated with increased risk of malignancy. For patients with malignancy developed beyond 5 years after the diagnosis of AAV, a significantly higher malignancy risk was observed in those with a cumulative cyclophosphamide dose over 20.0 g (SIR: 11.54; 95% CI: 4.77-27.93; p < 0.001). Within the first 2 years after the diagnosis of AAV, the risk of malignancy was still significantly higher than that in the general population, but the cumulative cyclophosphamide dose was not significantly associated with malignancy occurrence in this subgroup of patients. CONCLUSIONS: Malignancy risk is higher in Chinese AAV patients than that in the general population, with a different malignancy spectrum from western countries. Both the use of cyclophosphamide and AAV per se might be associated with higher incidence of malignancy occurrence.

FTY720 ameliorates experimental MPO-ANCA-associated vasculitis by regulating fatty acid oxidation via the neutrophil PPARα-CPT1a pathway.

OBJECTIVES: Increasing studies demonstrated the importance of C5a and anti-neutrophil cytoplasmic antibody (ANCA)-induced neutrophil activation in the pathogenesis of ANCA-associated vasculitis (AAV). Sphingosine-1-phosphate (S1P) acts as a downstream effector molecule of C5a and enhances neutrophil activation induced by C5a and ANCA. The current study investigated the role of a S1P receptor modulator FTY720 in experimental autoimmune vasculitis (EAV) and explored the immunometabolism-related mechanisms of FTY720 in modulating ANCA-induced neutrophil activation. METHODS: The effects of FTY720 in EAV were evaluated by quantifying hematuria, proteinuria, crescent formation, tubulointerstitial injury and pulmonary hemorrhage. RNA sequencing of renal cortex and gene enrichment analysis were performed. The proteins of key identified pathways were analyzed in neutrophils isolated from peripheral blood of patients with active AAV and normal controls. We assessed the effects of FTY720 on ANCA-induced neutrophil respiratory burst and neutrophil extracellular traps formation (NETosis). RESULTS: FTY720 treatment significantly attenuated renal injury and pulmonary hemorrhage in EAV. RNA sequencing analyses of renal cortex demonstrated enhanced fatty acid oxidation (FAO) and peroxisome proliferators-activated receptors (PPAR) signalling in FTY720-treated rats. Compared with normal controls, patients with active AAV showed decreased FAO in neutrophils. FTY720-treated differentiated HL-60 cells showed increased expression of carnitine palmitoyltransferase 1A (CPT1a) and PPARα. Blocking or knockdown of CPT1a or PPARα in isolated human neutrophils and HL-60 cells reversed the inhibitory effects of FTY720 on ANCA-induced neutrophil respiratory burst and NETosis. CONCLUSION: FTY720 attenuated renal injury in EAV through upregulating FAO via the PPARα-CPT1a pathway in neutrophils, offering potential immunometabolic targets in AAV treatment.

A Three-Dimensional Open-Framework Tin(II) Sulfate with Near-Unity Photoluminescence Quantum Yield.

A new open-framework tin(II) sulfate, formulated as C4H12N2·Sn(SO4)2·H2O, was prepared under the structure-directing effect of piperazine. This compound features a 3D structure with 16-ring channels. Under ultraviolet light irradiation, it emits bright yellow luminescence with a near-unity photoluminescence quantum yield. Theoretical calculations were carried out to understand the luminescence mechanism.

Microbial community evolution and individual-based model validation of biofilms in single-stage partial nitrification/anammox system.

In this study, matrix degradation, microbial community development, and distribution using an individual-based model during biofilm formation on carriers at varying depths within a single-stage partial nitrification/anammox system were simulated. The findings from the application of individual-based model fitting, fluorescence in situ hybridization, and high-throughput sequencing reveal the presence of aerobic bacteria, specifically ammonia-oxidizing bacteria, as discrete particles within the outer layer of the carrier. Facultative anaerobic bacteria exemplified by anaerobic ammonia-oxidizing bacteria, are observed as aggregates within the middle layer. Conversely, anaerobic bacteria, represented by denitrifiers, are enveloped by extracellular polymeric substances within the inner layer. The present study extends the application of individual-based model to the formation of polyurethane-supported biofilms and presents valuable avenues for the design and advancement of pragmatic engineering carriers.

Application of a Closed-Form Model in Analyzing the Fracture of Quasi-Brittle Materials.

Fracture failure in quasi-brittle materials poses a persistent challenge in materials science and engineering. This study presents a thorough investigation of the Boundary Effect Model (BEM), offering a nuanced understanding of the size effect on fracture properties. The conceptual framework, evolutionary process, and applicability scope of BEM are elucidated, highlighting its accuracy and reliability in calculating fracture properties across various quasi-brittle materials. Through the integration of BEM with diverse fracture tests-such as three-point bending, four-point bending, and wedge-splitting-a linear correlation between maximum failure loads and material fracture properties is established. Notably, the study demonstrates that fracture properties, determined by BEM, can be regarded as consistent material constants across specimens of varying sizes, initial notch lengths, geometries, and microstructures. Validation of the BEM's reliability encompasses the analysis of 140 fracture test results involving concrete, hard rocks, and bamboo scrimber. The synergy of non-linear and linear BEM analyses emerges as a robust approach for accurately predicting the fracture behavior of quasi-brittle materials. This comprehensive exploration sheds light on the potential of the Boundary Effect Model as a valuable tool for predicting and understanding fracture mechanics in diverse materials and scenarios. This research serves as an effective approach to accurately evaluating the fracture properties of quasi-brittle materials, which is of great practical significance for material design, engineering construction, and various industrial applications.

A Real-Time Evaluation Algorithm for Noncontact Heart Rate Variability Monitoring.

Noncontact vital sign monitoring based on radar has attracted great interest in many fields. Heart Rate Variability (HRV), which measures the fluctuation of heartbeat intervals, has been considered as an important indicator for general health evaluation. This paper proposes a new algorithm for HRV monitoring in which frequency-modulated continuous-wave (FMCW) radar is used to separate echo signals from different distances, and the beamforming technique is adopted to improve signal quality. After the phase reflecting the chest wall motion is demodulated, the acceleration is calculated to enhance the heartbeat and suppress the impact of respiration. The time interval of each heartbeat is estimated based on the smoothed acceleration waveform. Finally, a joint optimization algorithm was developed and is used to precisely segment the acceleration signal for analyzing HRV. Experimental results from 10 participants show the potential of the proposed algorithm for obtaining a noncontact HRV estimation with high accuracy. The proposed algorithm can measure the interbeat interval (IBI) with a root mean square error (RMSE) of 14.9 ms and accurately estimate HRV parameters with an RMSE of 3.24 ms for MEAN (the average value of the IBI), 4.91 ms for the standard deviation of normal to normal (SDNN), and 9.10 ms for the root mean square of successive differences (RMSSD). These results demonstrate the effectiveness and feasibility of the proposed method in emotion recognition, sleep monitoring, and heart disease diagnosis.

Insight into Eu3+-Doped Phase-Change K3Lu(PO4)2 Phosphate toward Data Encryption.

Adjusting the local coordination environment of lanthanide luminescent ions can modulate their crystal-field splittings and broaden their applications in the relevant optical fields. Here, we introduced Eu3+ ions into the phase-change K3Lu(PO4)2 phosphate and found that the temperature-induced reversible phase transitions of K3Lu(PO4)2 (phase I ⇆ phase II and phase II ⇆ phase III, below room temperature) give rise to an obvious photoluminescence (PL) difference of Eu3+ ions. The Eu3+ emission mainly focused on the 5D0 → 7F1 transition in phase III but manifested comparable 5D0 → 7F1,2 transitions in the two low-temperature phases. On this basis, the change of Eu3+-doped concentration led to the phase evolution in Eu3+:K3Lu(PO4)2, which could stabilize two types of low-temperature polymorphs to the specific temperature by controlling the doping content. Finally, we proposed a feasible information encryption strategy based on the PL modulation of Eu3+:K3Lu(PO4)2 phosphors, which was caused by the temperature hysteresis of the relevant phase transition, exhibiting good stability and reproducibility. Our findings pave an avenue for exploring the optical application of lanthanide-based luminescent materials by introducing phase-change hosts.

Physics-assisted machine learning methods for predicting the splitting tensile strength of recycled aggregate concrete.

Recycled aggregate concrete (RAC) has become a popular building material due to its eco-friendly features, but the difficulty in predicting the crack resistance of RAC is increasingly impeding its application. In this study, splitting tensile strength is adopted to describe the crack resistance ability of RAC, and physics-assisted machine learning (ML) methods are used to construct the predictive models for the splitting tensile strength of RAC. The results show that the AdaBoost model has excellent predictive performance with the help of the Firefly algorithm, and physical assistance plays a remarkable role in selecting features and verifying the ML models. Due to the limit in data size and the generalizability of the model, the dataset should be supplemented with more representative data, and an algorithm for small sample sizes could be studied in the future.

Bibliometric analysis and mini-review of global research on pyroptosis in the field of cancer.

Pyroptosis is one of the mechanisms of programmed cell death (PCD) activated by inflammasomes and involved by the caspase family and the gasdermin family. During the oncogenesis and progression of tumors, pyroptosis is crucial, and complex withal. Currently, pyroptosis is the focus topic in the research field of oncology, but there is no single bibliometric analysis systematically studying 'pyroptosis and cancer'. Our study aimed to visualize the research status of pyroptosis in oncology and excavate the hotspots and prospects in this field. Furthermore, in consideration of the professional direction of researchers, we particularly emphasized articles on pyroptosis in gynecology and formed a mini systematic review. This bibliometric work integrated and analyzed all articles from ISI Web of Science: Science Citation Index Expanded (SCI-Expanded) (dated April 25th, 2022), based on quantitative and visual mapping approaches. Systematically reviewing articles on pyroptosis in gynecology helped us complement our analysis of research advancements in this field. Including 634 articles, our study found that the number of articles on pyroptosis in cancer increased exponentially in recent years. These publications came from 45 countries and regions headed by China and the US mainly aiming at the mechanism of pyroptosis in cell biology and biochemistry molecular biology, as well as the role of pyroptosis in the development and therapeutic application of various cancers. The top 20 most cited studies on this topic mostly came from the US, followed by China and England, and half of the articles cited more than 100 times in total were published in Nature. Moreover, as for gynecologic cancer, in vitro and bioinformatics analysis were the main methodology conducting to explore roles of pyroptosis-related genes (PRGs) and formation of inflammasomes in cancer progression and prognosis. Pyroptosis has evolved into a burgeoning research field in oncology. The cellular and molecular pathway mechanism of pyroptosis, as well as the effect of pyroptosis in oncogenesis, progression, and treatment have been the hot topic of the current study and provided us the future direction as the potential opportunities and challenges. We advocate more active cooperation to improve therapeutic strategies for cancer.

Digested extracellular DNA shortens the anodic startup of microbial electrolysis cell.

While the multiple functions of extracellular DNA (exDNA) in biofilm formation and electron transfer have been extensively studied in pure culture, its role in mixed anodic biofilm was still unknown. In this study, we employed DNase I enzyme to digest exDNA, thereby investigating its role in anodic biofilm formation based on the performance of four microbial electrolysis cells (MECs) groups with different DNase I enzyme concentration (0, 0.05, 0.1, 0.5 mg/mL). The responding time to reach 60 % maximum current of treatment group with DNase I enzyme has been significantly reduced to 83 %-86 % of the blank group (t-test, p < 0.01), indicating the exDNA digestion could promote the biofilm formation at the early stage. The anodic coulombic efficiency was enhanced by 10.74- 54.42 % in treatment group (t-test, p < 0.05), which could be ascribed to the higher absolute abundance of exoelectrogens. The lower relative abundance of exoelectrogens indicated the DNase I enzyme addition was beneficial for the enrichment of extensive species rather than exoelectrogens. As the DNase I enzyme augments the fluorescence signal of exDNA distribution in the small molecular weight region, implying the short chain exDNA could contribute to the biomass enhancement via boosting the most species enrichment. Furthermore, the exDNA alteration improved the complexity of microbial network. Our findings provide a new insight into the role of exDNA in the extracellular matrix of anodic biofilms.

The ethyl acetate extract of Wenxia Changfu Formula inhibits the carcinogenesis of lung adenocarcinoma by regulating PI3K-AKT signaling pathway.

Lung adenocarcinoma is the most common type of lung cancer. With a rise in new cases worldwide each year, early diagnosis and treatment are very important. Network pharmacology provides the effective way to evaluate poly-pharmacological effects and anticancer molecular mechanisms of drugs. The aim of the present study was to explore the anti-tumor mechanism of ethyl acetate extract of Wenxia Changfu Formula (WFEA) in lung adenocarcinoma by using analytical chemistry, network pharmacology and molecular biology. A total of 193 compounds were identified from WFEA, mainly including esters, phenols, ketones and alkaloids. Totally, 374 targets were regarded as potential targets of WFEA against lung adenocarcinoma. Interestingly, PI3K-AKT was found to be one of the significantly enriched signaling pathways of targets of WFEA against lung adenocarcinoma. AKT1, MMP3, CASP3 and BCL2 had strong binding effect with compound molecules of WFEA. Some combinations with the best docking binding were identified, including quercetin/oleanolic_acid/emodin/aloe_emodin/catechin-AKT1 and quercetin-MMP3. In lung adenocarcinoma cells, the WFEA inhibited the proliferation, migration and invasion, and promoted the apoptosis. Moreover, the WFEA inhibited the mRNA expression of MMP3 and Bcl-2 and promoted the mRNA expression of Caspase3. In addition, WFEA inhibited the protein phosphorylation of AKT and PI3K. The WFEA had a significant inhibitory effect on lung adenocarcinoma cells, which could inhibit cell proliferation, invasion and metastasis, and induce cell apoptosis. The mechanism of action of WFEA may be involved in the regulation of the PI3K-AKT signaling pathway in the lung adenocarcinoma.

Changes in the gut microbiota of forest musk deer (Moschus berezovskii) during ex situ conservation.

Ex situ conservation is an important technique for protecting rare and endangered wildlife, and maintaining stable individual health is crucial to its success. Gut microbiota composition is a critical indicator of animal health and should therefore be closely monitored during ex situ conservation to track impacts on animal health. Forest musk deer (Moschus berezovskii) were historically distributed in Hebei Province, China, however, they are now extinct in the region. Thus, ex situ conservation efforts were conducted in 2016 whereby approximately 50 individuals were artificially migrated from Weinan, Shaanxi to Huailai, Hebei. To monitor gut health of these migrated individuals, we used 16S rRNA high-throughput sequencing technology to examine the microbiota differences between Huailai juvenile and Weinan juvenile groups, and between Huailai adult and Weinan adult groups. Alpha diversity analysis indicated that the richness of microbiota significantly decreased after migration to the Huailai area, and the beta diversity results also showed significant dissimilarity in gut microbial communities, demonstrating the distinct microbial structure differences in the forest musk deer population from the two areas, for both juvenile and adult groups, respectively. In addition, PICRUSt functional profile prediction indicated that the functions of gut digestion and absorption, and degradation of toxic substances were significantly weakened after ex situ conservation. Differences in diet composition between the individuals of the two sites were also observed and the impact of food on gut microbiota compositions within forest musk deer during ex situ conservation was investigated. This study provides a theoretical basis for developing ex situ conservation measures, especially for the protection of forest musk deer.

Causality and correlation analysis for deciphering the microbial interactions in activated sludge.

Time series data has been considered to be a massive information provider for comprehending more about microbial dynamics and interaction, leading to a causality inference in a complex microbial community. Granger causality and correlation analysis have been investigated and applied for the construction of a microbial causal correlation network (MCCN) and efficient prediction of the ecological interaction within activated sludge, which thereby exhibited ecological interactions at the OTU-level. Application of MCCN to a time series of activated sludge data revealed that the hub species OTU56, classified as the one belonging to the genus Nitrospira, was responsible for nitrification in activated sludge and interaction with Proteobacteria and Bacteroidetes in the form of amensal and commensal relationships, respectively. The phylogenetic tree suggested a mutualistic relationship between Nitrospira and denitrifiers. Zoogloea displayed the highest ncf value within the classified OTUs of the MCCN, indicating that it could be a foundation for activated sludge through the formation of characteristic cell aggregate matrices where other organisms embed during floc formation. Inclusively, the research outcomes of this study have provided a deep insight into the ecological interactions within the communities of activated sludge.

Molecular Insight into the Binding of Astilbin with Human Serum Albumin and Its Effect on Antioxidant Characteristics of Astilbin.

Astilbin is a dihydroflavonol glycoside identified in many natural plants and functional food with promising biological activities which is used as an antioxidant in the pharmaceutical and food fields. This work investigated the interaction between astilbin and human serum albumin (HSA) and their effects on the antioxidant activity of astilbin by multi-spectroscopic and molecular modeling studies. The experimental results show that astilbin quenches the fluorescence emission of HSA through a static quenching mechanism. Astilbin and HSA prefer to bind at the Site Ⅰ position, which is mainly maintained by electrostatic force, hydrophobic and hydrogen bonding interactions. Multi-spectroscopic and MD results indicate that the secondary structure of HSA could be changed because of the interaction of astilbin with HSA. DPPH radical scavenging assay shows that the presence of HSA reduces the antioxidant capacity of astilbin. The explication of astilbin-HSA binding mechanism will provide insights into clinical use and resource development of astilbin in food and pharmaceutical industries.

Tracking the diversity and interaction of methanogens in the energy recovery process of a full-scale wastewater treatment plant.

Methanogens have been significant for the achievement of carbon neutrality in wastewater treatment plants due to their crucial roles in the anaerobic digestion of sludge. Nevertheless, the phylogenetic diversity of methanogens and their versatile metabolism have been continuously investigated, the current scientific knowledge regarding these microbes appears inadequate and requires more evaluations. This study is considered an endeavor in which functional genes sequencing was used to reveal the diversity of methanogens in the sludge process of the wastewater treatment plant. The information obtained was substantially more than that employing 16s sequencing. The methanogenic microbial resources were appropriate to sustain a self-inoculated energy recovery with a potential ability to boost methane production. A constancy was observed in 16 S rRNA gene and mcrA gene sequencing results, where the bacterial or Methanosaeta concilii dominated community of DS (digest sludge) was distinct from the inoculum sources TS (total sludge), CTS (concentrated total sludge), and HTS (hydrolysis total sludge), indicating the independent development of DS. A quantitative cross-network was constructed by coupling the absolute quantify of 16 S rRNA and mcrA sequences. The Methanobacterium petrolearium actively interacted with bacteria in the DS community rather than the dominant species (Methanosaeta concilii). Moreover, the unclassified methanogens were identified to be significantly prevalent in all communities, suggesting that unknown methanogenic taxa might be imperative in accomplishing community functions. Collectively, the findings of this research study will shed light on the comprehensive knowledge of microbial communities, especially the methanogenic microbiota. This will further enhance the exploration of the phylogenetic diversity of methanogens and their corresponding impacts in energy recovery from wastewater treatment plants.

Androgen plays an important role in regulating the synthesis of pheromone in the scent gland of muskrat.

The scent (musk) gland is an organ unique to muskrats and other scent-secreting animals, and the pheromones (musk) synthesized and secreted by the scent gland play a role in chemical communication among scent-secreting animals. The musk gland is synchronized with testicular developmental changes; however, little is known regarding androgen secretion from the testis and how this regulates pheromone synthesis and the secretion of scent. To investigate the effect of androgens on the synthesis of pheromones in the musk gland, we established a muskrat castration model by surgical removal of the testis, and analyzed the histomorphology, hormone concentration, gene expression, and changes in the chemical composition of the musk gland in castration and control groups by histomorphological analysis, Enzyme-Linked ImmunoSorbent Assay (ELISA), RNA sequencing (RNA-seq), and gas chromatography-mass spectrometry (GCMS). Histomorphological analysis results showed that after castration, muskrat gland cells underwent significant atrophy (P < 0.05). Hormone measurement results showed that there was a significant decrease in serum testosterone and muskrat musk testosterone (P < 0.05) after muskrat castration. Transcriptome sequencing results showed that 510 differentially expressed transcripts (DETs) were mainly enriched in fatty acid metabolism, terpenoid backbone biosynthesis, fatty acid degradation, PPAR signaling pathway, and fatty acid biosynthesis. GCMS results showed that macrocyclic ketones, steroids, fatty acids, alcohols, and esters in musk were significantly changed (P < 0.05). In conclusion, androgens were found to play an important function in the chemical communication exchange between muskrats through regulating pheromone synthesis in musk cells. This study provides a basis for understanding the mechanism of animal communication influenced by androgens.

Enhancing the Photoluminescence Property of Pr3+ Ions by Understanding the Polymorphous Influence of the K3Lu(PO4)2 Host.

Adjusting the local coordination environment of lanthanide luminescent ions is a useful method to manipulate the relevant photoluminescence (PL) property. K3Lu(PO4)2 is a phase-change material, and according to the stable temperature range from low to high, the related polymorphs are phase I [P21/m, coordination number (CN) of Lu3+ = 7], phase II (P21/m, CN = 6), and phase III (P3̅, CN = 6), respectively. Based on the temperature-dependent PL analysis of K3Lu(PO4)2:Pr3+, we find that Pr3+ ions occupy the noninversion sites (Cs) in the two low-temperature phases but preferentially enter into the inversion ones (C3i) in phase III. Compared to Pr3+-doped phase I (78 K), Pr3+ ions in phase III (300 K) manifest a weaker fluorescence intensity (170-fold lower). To enhance the room-temperature PL property of K3Lu(PO4)2:Pr3+, a polymorphous adjustment strategy was proposed by the use of the ion-doping method. By introducing the Gd3+ ions into the lattice, Pr3+-doped phase I is successfully stabilized to room temperature, manifesting a 27-fold fluorescence increase in comparison to K3Lu(PO4)2:Pr3+ (0.1 at. %). The finding discussed in this study highlights the significance of site engineering for luminescent ions and also presents the application value of phase-change hosts in the development of high-performance luminescent materials.

Ab initio theory study of laser cooling of barium monohalides.

The feasibility of laser cooling barium monohalides BaX (X = F, Cl, Br, I) is investigated using ab initio methods with the inclusion of spin-orbit coupling (SOC) effects. Calculated spectroscopic constants for BaF, BaCl, BaBr and BaI are in very good agreement with the available experimental measurements. The results demonstrate that the calculated electronic structure is accurate and can be used to establish the optical scheme of laser cooling. The highly diagonal Franck-Condon factors (FCFs) (BaF: f 00 = 0.980, f 11 = 0.939, f 22 = 0.894; BaCl: f 00 = 0.998, f 11 = 0.995, f 22 = 0.992) between the X2Σ+ 1/2 and A2Π1/2 states are determined, which are found to be in good agreement with previous theoretical results. The radiative lifetimes (BaF: 39.13-41.20 ns; BaCl: 117.99-110.23 ns) of the A2Π1/2-X2Σ+ 1/2 transition for the first five vibrational levels show that the A2Π1/2 is a rather short lifetime state. The current study indicates that BaF and BaCl are two good choices of molecules for laser cooling. Therefore, BaI and BaBr are not promising laser-cooling candidates because the FCFs of the A2Π1/2-X2Σ+ 1/2 transition are off-diagonal. We further propose the three-laser cooling schemes based on the A2Π1/2-X2Σ+ 1/2 transition for BaF and BaCl.

The Inducible CYP4C71 Can Metabolize Imidacloprid in Laodelphax striatellus (Hemiptera: Delphacidae).

Laodelphax striatellus (Fallén) is an important rice pest species which has developed high resistance to imidacloprid. Previous studies have demonstrated that CYP6AY3v2 and CYP353D1v2 were constitutively overexpressed in a imidacloprid resistant strain and can metabolize imidacloprid to mediated metabolic resistance. Further studies still needed to explore whether there are other L. striatellus P450 enzymes that can also metabolize imidacloprid. In this study, the expression level of L. striatellus CYP4C71 was significantly upregulated both in laboratory strains and field strains of L. striatellus after imidacloprid treatment for 4 h. The capability of CYP4C71 to metabolize imidacloprid was investigated. The full-length CYP4C71 was cloned, and its open reading frame was 1,515 bp with an enzyme estimated to be 505 amino acid residues in size. Furthermore, CYP4C71 was heterologously expressed along with L. striatellus cytochrome P450 reductase (CPR) in insect cells. A carbon monoxide difference spectra analysis confirmed the successful expression of CYP4C71. The recombinant CYP4C71 showed high P450 O-demethylation activity with PNP as a substrate. In vitro metabolism studies showed that recombinant CYP4C71 can metabolize imidacloprid to an easily excreted hydroxy-form. The rate of imidacloprid depletion in response to imidacloprid concentration revealed Michaelis Menten kinetics (R2 fitted curve = 0.99) with a relative low affinity: Kcat = 0.032 ± 0.009 pmol depleted imidacloprid/min/pmol P450 and Km=85.19 ± 2.93 µM. A relative big Km (85.19 ± 2.93 µM) indicated relative low imidacloprid's affinity for the CYP4C71 enzyme. In conclusion, CYP4C71 was another P450 enzyme that can metabolize imidacloprid with a relatively low affinity.