Rice false smut virulence protein subverts host chitin perception and signaling at lemma and palea for floral infection.

The flower-infecting fungus Ustilaginoidea virens causes rice false smut, which is a severe emerging disease threatening rice (Oryza sativa) production worldwide. False smut not only reduces yield, but more importantly produces toxins on grains, posing a great threat to food safety. U. virens invades spikelets via the gap between the 2 bracts (lemma and palea) enclosing the floret and specifically infects the stamen and pistil. Molecular mechanisms for the U. virens-rice interaction are largely unknown. Here, we demonstrate that rice flowers predominantly employ chitin-triggered immunity against U. virens in the lemma and palea, rather than in the stamen and pistil. We identify a crucial U. virens virulence factor, named UvGH18.1, which carries glycoside hydrolase activity. Mechanistically, UvGH18.1 functions by binding to and hydrolyzing immune elicitor chitin and interacting with the chitin receptor CHITIN ELICITOR BINDING PROTEIN (OsCEBiP) and co-receptor CHITIN ELICITOR RECEPTOR KINASE1 (OsCERK1) to impair their chitin-induced dimerization, suppressing host immunity exerted at the lemma and palea for gaining access to the stamen and pistil. Conversely, pretreatment on spikelets with chitin induces a defense response in the lemma and palea, promoting resistance against U. virens. Collectively, our data uncover a mechanism for a U. virens virulence factor and the critical location of the host-pathogen interaction in flowers and provide a potential strategy to control rice false smut disease.

Desflurane improves electrical activity of neurons and alleviates oxygen-glucose deprivation-induced neuronal injury by activating the Kcna1-dependent Kv1.1 channel.

Several volatile anesthetics have presented neuroprotective functions in ischemic injury. This study investigates the effect of desflurane (Des) on neurons following oxygen-glucose deprivation (OGD) challenge and explores the underpinning mechanism. Mouse neurons HT22 were subjected to OGD, which significantly reduced cell viability, increased lactate dehydrogenase release, and promoted cell apoptosis. In addition, the OGD condition increased oxidative stress in HT22 cells, as manifested by increased ROS and MDA contents, decreased SOD activity and GSH/GSSG ratio, and reduced nuclear protein level of Nrf2. Notably, the oxidative stress and neuronal apoptosis were substantially blocked by Des treatment. Bioinformatics suggested potassium voltage-gated channel subfamily A member 1 (Kcna1) as a target of Des. Indeed, the Kcna1 expression in HT22 cells was decreased by OGD but restored by Des treatment. Artificial knockdown of Kcna1 negated the neuroprotective effects of Des. By upregulating Kcna1, Des activated the Kv1.1 channel, therefore enhancing K+ currents and inducing neuronal repolarization. Pharmacological inhibition of the Kv1.1 channel reversed the protective effects of Des against OGD-induced injury. Collectively, this study demonstrates that Des improves electrical activity of neurons and alleviates OGD-induced neuronal injury by activating the Kcna1-dependent Kv1.1 channel.

Long term survival outcomes of surgery combined with hyperthermic intraperitoneal chemotherapy for perforated low-grade appendiceal mucinous neoplasms: A multicenter retrospective study.

BACKGROUND: Low-grade appendiceal mucinous neoplasms (LAMN) are very rare, accounting for approximately 0.2%-0.5% of gastrointestinal tumors. We conducted a multicenter retrospective study to explore the impact of different surgical procedures combined with HIPEC on the short-term outcomes and long-term survival of patients. METHODS: We retrospectively analyzed the clinicopathological data of 91 LAMN perforation patients from 9 teaching hospitals over a 10-year period, and divided them into HIPEC group and non-HIPEC group based on whether or not underwent HIPEC. RESULTS: Of the 91 patients with LAMN, 52 were in the HIPEC group and 39 in the non-HIPEC group. The Kaplan-Meier method predicted that 52 patients in the HIPEC group had 5- and 10-year overall survival rates of 82.7% and 76.9%, respectively, compared with predicted survival rates of 51.3% and 46.2% for the 39 patients in the non-HIPEC group, with a statistically significant difference between the two groups (χ2 = 10.622, p = 0.001; χ2 = 10.995, p = 0.001). Compared to the 5-year and 10-year relapse-free survival rates of 75.0% and 65.4% in the HIPEC group, respectively, the 5-year and 10-year relapse-free survival rates of 48.7% and 46.2% in the non-HIPEC group were significant different between the two outcomes (χ2 = 8.063, p = 0.005; χ2 = 6.775, p = 0.009). The incidence of postoperative electrolyte disturbances and hypoalbuminemia was significantly higher in the HIPEC group than in the non-HIPEC group (p = 0.023; p = 0.044). CONCLUSIONS: This study shows that surgery combined with HIPEC can significantly improve 5-year and 10-year overall survival rates and relapse-free survival rates of LAMN perforation patients, without affecting their short-term clinical outcomes.

Synthesis and Structure-Activity Analysis of Icaritin Derivatives as Potential Tumor Growth Inhibitors of Hepatocellular Carcinoma Cells.

The prenylated flavonoid icaritin (ICT, 1), a new drug for treating advanced hepatocellular carcinoma (HCC), was selected as a template to develop more potent inhibitors. An initial semisynthetic modification of ICT was performed to obtain a structure-activity relationship (SAR), which indicated that the cytotoxicity is enhanced by OH-3 rhamnosylation and that OH-7 is an important modification site. Based on the results of the SAR study, 46 N-containing ICT derivatives were synthesized and evaluated as the anti-HCC inhibitors. The results showed that most of the derivatives produced inhibited three HCC cell lines used (Hep3B, HepG2 and SMMC-7721). The modification strategy was validated by 3D-QSAR, which provided information for the further design and optimization of ICT. The most potent compound, 11c, exhibited IC50 values of 7.6 and 3.1 µM against HepG2 and SMMC-7721 cells, respectively, which were more potent than those of ICT and sorafenib, respectively. Further mechanistic studies indicated that 11c caused arrest at the G0/G1 phase in the cell cycle and induced cell apoptosis in HepG2 and SMMC-7721 cells.

Short- and long-term outcomes of laparoscopic or robotic radical gastrectomy based on preoperative perigastric artery CTA surgical decision-making: a high-volume center retrospective study with propensity score matching.

BACKGROUND: Some studies have demonstrated the short-term recovery course for patients who underwent laparoscopic gastrectomy according to preoperative computed tomography angiography (CTA) assessment. However, reports of the long-term oncological outcomes are still limited. METHODS: The data of 988 consecutive patients who underwent laparoscopic or robotic radical gastrectomy between January 2014 and September 2018 were analyzed retrospectively at our center, and propensity score matching was used to eliminate bias. Study cohorts were divided into the CTA group (n = 498) and the non-CTA group (n = 490) depending on whether preoperative CTA was available. The primary and secondary endpoints were the 3-year overall survival (OS) and disease-free survival (DFS) rates and the intraoperative course and short-term outcomes, respectively. RESULTS: 431 patients were included in each group after PSM. Compared with the non-CTA group, the CTA group had more harvested lymph nodes and less operative time, blood loss, intraoperative vascular injury and total cost, especially in the subgroup analysis with BMI ≥ 25 kg/m2 patients. There was no difference in the 3 year OS and DFS between the CTA group and the non-CTA group. When further stratified by BMI < 25 or ≥ 25 kg/m2, the 3-year OS and DFS were significantly higher in the CTA group than in the non-CTA group in terms of BMI ≥ 25 kg/m2. CONCLUSIONS: Laparoscopic or robotic radical gastrectomy based on preoperative perigastric artery CTA surgical decision-making has the possibility of improving short-term outcomes. However, there is no difference in the long-term prognosis, except for a subgroup of patients with BMI ≥ 25 kg/m2.

Action Recognition Based on Multi-Level Topological Channel Attention of Human Skeleton.

In action recognition, obtaining skeleton data from human poses is valuable. This process can help eliminate negative effects of environmental noise, including changes in background and lighting conditions. Although GCN can learn unique action features, it fails to fully utilize the prior knowledge of human body structure and the coordination relations between limbs. To address these issues, this paper proposes a Multi-level Topological Channel Attention Network algorithm: Firstly, the Multi-level Topology and Channel Attention Module incorporates prior knowledge of human body structure using a coarse-to-fine approach, effectively extracting action features. Secondly, the Coordination Module utilizes contralateral and ipsilateral coordinated movements in human kinematics. Lastly, the Multi-scale Global Spatio-temporal Attention Module captures spatiotemporal features of different granularities and incorporates a causal convolution block and masked temporal attention to prevent non-causal relationships. This method achieved accuracy rates of 91.9% (Xsub), 96.3% (Xview), 88.5% (Xsub), and 90.3% (Xset) on NTU-RGB+D 60 and NTU-RGB+D 120, respectively.

Chamaejasmenin E from Stellera chamaejasme induces apoptosis of hepatocellular carcinoma cells by targeting c-Met in vitro and in vivo.

Hepatocellular carcinoma (HCC), the most prevalent liver cancer, is considered one of the most lethal malignancies with a dismal outcome. There is an urgent need to find novel therapeutic approaches to treat HCC. At present, natural products have served as a valuable source for drug discovery. Here, we obtained five known biflavones from the root of Stellera chamaejasme and evaluated their activities against HCC Hep3B cells in vitro. Chamaejasmenin E (CE) exhibited the strongest inhibitory effect among these biflavones. Furthermore, we found that CE could suppress the cell proliferation and colony formation, as well as the migration ability of HCC cells, but there was no significant toxicity on normal liver cells. Additionally, CE induced mitochondrial dysfunction and oxidative stress, eventually leading to cellular apoptosis. Mechanistically, the potential target of CE was predicted by database screening, showing that the compound might exert an inhibitory effect by targeting at c-Met. Next, this result was confirmed by molecular docking, cellular thermal shift assay (CETSA), as well as RT-PCR and Western blot analysis. Meanwhile, CE also reduced the downstream proteins of c-Met in HCC cells. In concordance with above results, CE is efficacious and non-toxic in tumor xenograft model. Taken together, our findings revealed an underlying tumor-suppressive mechanism of CE, which provided a foundation for identifying the target of biflavones.

Short- and long-term comparison of robotic and laparoscopic gastrectomy for gastric cancer by the same surgical team: a propensity score matching analysis.

BACKGROUND: Research on short-term outcomes and oncology results after robotic gastrectomy (RG) is still limited, especially from a single surgical team. The purpose of this study was to compare the short-term and long-term outcomes of robotic and laparoscopic gastrectomy (LG). METHODS: Between October 2014 and September 2019, 1686 consecutive patients who underwent MIS gastrectomy were enrolled. The patients were divided into RG and LG groups according to surgical type. Groups were matched at a 1:1 ratio using propensity scores based on the following variables: age, sex, ASA score, primary tumor location, histologic type, pathological stage, and neoadjuvant chemotherapy. The primary outcomes were 3-year overall survival (OS) and relapse-free survival (RFS). The secondary outcomes were postoperative short-term outcomes. RESULTS: Demographic and baseline characteristics were similar between the two groups after matching. Compared to the LG group, the RG group had a significantly higher retrieved lymph node (LN) number (32.15 vs 30.82, P = 0.040), more retrieved supra-pancreatic LNs (12.45 vs 11.61, P = 0.028), lower estimated blood loss (73.67 vs 98.08 ml, P < 0.001), but longer operation time (205.18 vs 185.27 min, P < 0.001) and higher hospitalization costs ($13,607 vs $10,928, P < 0.001) in the matched cohort. In the subgroup analysis, we observed that compared with LG, patients with advanced gastric cancer benefitted more from RG surgery. The matched cohort analysis demonstrated no statistically significant differences for 3-year OS or RFS (log-rank, P = 0.648 and P = 0.951, respectively): 80.3% and 77.0% in LG vs. 81.2% and 76.6% in RG, respectively. CONCLUSION: RG has certain technical advantages over LG, especially in patients with advanced gastric cancer. However, RG does not improve long-term oncology outcomes.

Insight into Isolation and Characterization of Phenolic Compounds from Hawthorn (Crataegus pinnatifida Bge.) with Antioxidant, Anti-Acetylcholinesterase, and Neuroprotective Activities.

Recent epidemiologic studies have demonstrated a link between the consumption of daily functional fruits rich in phenols and the prevention of disease for neurodegenerative disorders. Hawthorn products are derived from the functional fruit hawthorn, which is rich in phenols and has been used around the world for centuries. In order to explore the phenolic components in hawthorn, the investigation of the ethanol extract led to the separation of five new phenol compounds (1a/1b, 2-4), including one pair of enantiomers (1a/1b), along with seven disclosed analogs (5-11). Their structures were elucidated based on extensive spectroscopic analyses and electronic circular dichroism (ECD). The compounds (1-11) were tested for antioxidant activities by 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonicacid) (ABTS), and ferric reducing antioxidant power (FRAP) methods. Apart from that, monomeric compounds 2, 4, and 6 exhibited more potent protective capabilities against H2O2 (hydrogen peroxide)-induced SH-SY5Y cells. Meanwhile, electronic analyses were performed using the highest occupied molecular orbital (HOMO), and the lowest unoccupied molecular orbital (LUMO) to analyze compounds 2, 4, and 6. Furthermore, compounds (1-11) measured acetylcholinesterase (AChE) inhibitory activities, and 2, 4, and 6 possessed greater AChE inhibitory activity than donepezil. At the same time, molecular docking was used to investigate the possible mechanism of the interaction between active compounds (2, 4, and 6) and AChE.

SGCS: a signal reconstruction method based on Savitzky-Golaysgz filtering and compressed sensing for wavelength modulation spectroscopy.

The residual oxygen concentration in pharmaceutical glass vial variously threatens the aseptic properties of encapsulated agents. The demodulated 2nd harmonic signals in the wavelength modulation spectroscopy (WMS) detection system, the data basis of the inversion of oxygen concentration, are inevitably destroyed by various time-varying industrial noises. In this work, we propose a signal reconstruction method based on self-correcting Savitzky-Golaysgz filter and compressed sensing (namely SGCS) for the urgent signal denoising task, which is a dual-step lightweight denoising scheme. First, in order to avoid the influence of glitch noise on sparse signal reconstruction, Savitzky-Golay (S-G) filter is used to smooth the 2nd harmonic signal while retaining the change information effectively. Then, the well-tuned measurement matrix of compressed-sensing (CS) is applied to aggressively fetch the sparse principal components while bypassing most residual dynamic noises. Finally, the orthogonal matching pursuit (OMP) is used to reconstruct the 2nd harmonic signal according to sparsity constrain and the sparse principal components. Experimental results show that the performance of SGCS method is superior. Compared with other competitive methods the operation time of SGCS is the shortest. When the normalized SNR is 1, the average correct discrimination rate is 98.57%. Even if SNR reduces from 1 to 0.55, the WMS detection system still survives well, with the highest average correct discrimination rate of 89.34%.

A novel prognostic factor TIPE2 inhibits cell proliferation and promotes apoptosis in pancreatic ductal adenocarcinoma (PDAC).

Background: Tumor necrosis factor (TNF)-alpha-induced protein 8-like 2 (TIPE2 or TNFAIP8L2) is a newly discovered negative immune regulator. Studies have shown that TIPE2 causes significant malignant biological effects and is differentially expressed in various malignant tumors. However, the expression and roles of TIPE2 in pancreatic ductal adenocarcinoma (PDAC) are largely unknown. Materials and Methods: The expression of TIPE2 in PDAC tissues was assessed by immunohistochemistry, qPCR and western blot analysis and related clinicopathological parameters including survival time were analyzed. After overexpression of TIPE2, cell proliferation and apoptosis analysis were conducted, and the associated underlying molecular mechanism was also explored. Results: In the present study, TIPE2 was upregulated in early PDAC tissues, and TIPE2 expression decreased as the tumor progressed (P<0.001). TIPE2 expression was negatively associated with tumor size, TNM stage and metastasis of lymph nodes. Furthermore, as an independent risk factor, TIPE2 could be used to predict the survival of patients with PDAC (P=0.035). TIPE2 overexpression significantly suppressed the viability, proliferation and induced apoptosis of PDAC cells by inhibiting survivin and increasing the activity of caspase3/7. Conclusions: For the first time, this study demonstrated that TIPE2 is an independent prognostic factor in PDAC. TIPE2 inhibited the proliferation and induced apoptosis via regulating survivin/caspase3/7 signaling pathway. These results indicated that TIPE2 is a potential biomarker for predicting the prognosis of PDAC patients and plays a pivotal role in the progression of PDAC.

Prognostic Factors for Primary Localized Gastrointestinal Stromal Tumors After Radical Resection: Shandong Gastrointestinal Surgery Study Group, Study 1201.

BACKGROUND: Most previous risk-prediction models for gastrointestinal stromal tumors (GISTs) were based on Western populations. In the current study, we collected data from 23 hospitals in Shandong Province, China, and used the data to examine prognostic factors in Chinese patients and establish a new recurrence-free survival (RFS) prediction model. METHODS: Records were analyzed for 5285 GIST patients. Independent prognostic factors were identified using Cox models. Receiver operating characteristic curve analysis was used to compare a novel RFS prediction model with current risk-prediction models. RESULTS: Overall, 4216 patients met the inclusion criteria and 3363 completed follow-up. One-, 3-, and 5-year RFS was 94.6% (95% confidence interval [CI] 93.8-95.4), 85.9% (95% CI 84.7-87.1), and 78.8% (95% CI 77.0-80.6), respectively. Sex, tumor location, size, mitotic count, and rupture were independent prognostic factors. A new prognostic index (PI) was developed: PI = 0.000 (if female) + 0.270 (if male) + 0.000 (if gastric GIST) + 0.350 (if non-gastric GIST) + 0.000 (if no tumor rupture) + 1.259 (if tumor rupture) + 0.000 (tumor mitotic count < 6 per 50 high-power fields [HPFs]) + 1.442 (tumor mitotic count between 6 and 10 per 50 HPFs) + 2.026 (tumor mitotic count > 10 per 50 HPFs) + 0.096 × tumor size (cm). Model-predicted 1-, 3-, and 5-year RFS was S(12, X) = 0.9926exp(PI), S(36, X) = 0.9739exp(PI) and S(60, X) = 0.9471exp(PI), respectively. CONCLUSIONS: Sex, tumor location, size, mitotic count, and rupture were independently prognostic for GIST recurrence. Our RFS prediction model is effective for Chinese GIST patients.

Mnn10 Maintains Pathogenicity in Candida albicans by Extending α-1,6-Mannose Backbone to Evade Host Dectin-1 Mediated Antifungal Immunity.

The cell wall is a dynamic structure that is important for the pathogenicity of Candida albicans. Mannan, which is located in the outermost layer of the cell wall, has been shown to contribute to the pathogenesis of C. albicans, however, the molecular mechanism by which this occurs remains unclear. Here we identified a novel α-1,6-mannosyltransferase encoded by MNN10 in C. albicans. We found that Mnn10 is required for cell wall α-1,6-mannose backbone biosynthesis and polysaccharides organization. Deletion of MNN10 resulted in significant attenuation of the pathogenesis of C. albicans in a murine systemic candidiasis model. Inhibition of α-1,6-mannose backbone extension did not, however, impact the invasive ability of C. albicans in vitro. Notably, mnn10 mutant restored the invasive capacity in athymic nude mice, which further supports the notion of an enhanced host antifungal defense related to this backbone change. Mnn10 mutant induced enhanced Th1 and Th17 cell mediated antifungal immunity, and resulted in enhanced recruitment of neutrophils and monocytes for pathogen clearance in vivo. We also demonstrated that MNN10 could unmask the surface ß-(1,3)-glucan, a crucial pathogen-associated molecular pattern (PAMP) of C. albicans recognized by host Dectin-1. Our results demonstrate that mnn10 mutant could stimulate an enhanced Dectin-1 dependent immune response of macrophages in vitro, including the activation of nuclear factor-κB, mitogen-activated protein kinase pathways, and secretion of specific cytokines such as TNF-α, IL-6, IL-1ß and IL-12p40. In summary, our study indicated that α-1,6-mannose backbone is critical for the pathogenesis of C. albicans via shielding ß-glucan from recognition by host Dectin-1 mediated immune recognition. Moreover, our work suggests that inhibition of α-1,6-mannose extension by Mnn10 may represent a novel modality to reduce the pathogenicity of C. albicans.

Interface engineering of a CoO(x)/Ta3N5 photocatalyst for unprecedented water oxidation performance under visible-light-irradiation.

Cocatalysts have been extensively used to promote water oxidation efficiency in solar-to-chemical energy conversion, but the influence of interface compatibility between semiconductor and cocatalyst has been rarely addressed. Here we demonstrate a feasible strategy of interface wettability modification to enhance water oxidation efficiency of the state-of-the-art CoO(x)/Ta3N5 system. When the hydrophobic feature of a Ta3N5 semiconductor was modulated to a hydrophilic one by in situ or ex situ surface coating with a magnesia nanolayer (2-5 nm), the interfacial contact between the hydrophilic CoO(x) cocatalyst and the modified hydrophilic Ta3N5 semiconductor was greatly improved. Consequently, the visible-light-driven photocatalytic oxygen evolution rate of the resulting CoO(x)/MgO(in)-Ta3N5 photocatalyst is ca. 23 times that of the pristine Ta3N5 sample, with a new record (11.3%) of apparent quantum efficiency (AQE) under 500-600 nm illumination.

Facile synthesis of chiral spirooxindole-based isotetronic acids and 5-1H-pyrrol-2-ones through cascade reactions with bifunctional organocatalysts.

Unprecedented organocatalyzed asymmetric cascade reactions have been developed for the facile synthesis of chiral spirooxindole-based isotetronic acids and 5-1H-pyrrol-2-ones.The asymmetric 1,2-addition reactions of α-ketoesters to isatins and imines by using an acid-base bifunctional 6'-OH cinchona alkaloid catalyst, followed by cyclization and enolization of the resulting adducts, gave chiral spiroisotetronic acids and 5-1H-pyrrol-2-ones, respectively, in excellent optical purities (up to 98 % ee). FT-IR analysis supported the existence of hydrogen-bonding interaction between the 6'-OH group of the cinchona catalyst and an isatin carbonyl group, an interaction that might be crucial for catalyst activity and stereocontrol.

Synergetic effect of dual cocatalysts in photocatalytic H2 production on Pd-IrOx/TiO2: a new insight into dual cocatalyst location.

Introducing appropriate dual cocatalysts is one of the most efficient strategies to improve the photocatalytic activity. Herein, we investigated the promotion effect of dual cocatalysts on TiO2 for hydrogen production. Compared with the Pd/TiO2 and Ir/TiO2 with the individual cocatalyst, TiO2 coloaded with Pd and Ir species exhibited an obviously enhanced H2 production activity and reduced CO/H2 ratio. XPS and IR spectra of CO adsorption analysis indicated that the dual cocatalysts on TiO2 were actually composed of Pd(0) and partially oxidized IrOx, which acted as the reduction and oxidation cocatalysts, respectively. Interestingly, EDX elemental mappings of Pd and Ir indicated that the two elements on TiO2 were inclined to depositing together. The synergetic effect of reduction and oxidation cocatalysts with their intimate contact is proposed to contribute to the high H2 production activity, which is different from the common view that the reduction and oxidation sites should be spatially separated to avoid the charge recombination.

Diel variability of carbon dioxide concentrations and emissions in a largest urban lake, Central China: Insights from continuous measurements.

Accurately quantifying the carbon dioxide (CO2) emissions from lakes, especially in urban areas, remains challenging due to constrained temporal resolution in field monitoring. Current lake CO2 flux estimates primarily rely on daylight measurements, yet nighttime emissions is normally overlooked. In this study, a non-dispersive infrared CO2 sensor was applied to measure dissolved CO2 concentrations over a 24-h period in a largest urban lake (Tangxun Lake) in Wuhan City, Central China, yielding extensive data on diel variability of CO2 concentrations and emissions. We showed the practicality and efficiency of the sensor for real-time continuous measurements in lakes. Our findings revealed distinct diurnal variations in CO2 concentrations (Day: 38.58 ± 23.8 µmol L-1; Night: 42.01 ± 20.2 µmol L-1) and fluxes (Day: 7.68 ± 10.34 mmol m-2 d-1; Night: 9.68 ± 9.19 mmol m-2 d-1) in the Tangxun Lake. The balance of photosynthesis and respiration is of utmost importance in modulating diurnal CO2 dynamics and can be influenced by nutrient loadings and temperature. A diel variability correction factor of 1.14 was proposed, suggesting that daytime-only measurements could underestimate CO2 emissions in urban lakes. Our data suggested that samplings between 11:00 and 12:00 could better represent the average diel CO2 fluxes. This study offered valuable insights on the diel variability of CO2 fluxes, emphasizing the importance of in situ continuous measurements to accurately quantify CO2 emissions, facilitating selections of sampling strategies and formulation of management strategies for urban lakes.

A novel automatic segmentation method directly based on magnetic resonance imaging K-space data for auxiliary diagnosis of glioma.

Background: The use of segmentation architectures in medical imaging, particularly for glioma diagnosis, marks a significant advancement in the field. Traditional methods often rely on post-processed images; however, key details can be lost during the fast Fourier transformation (FFT) process. Given the limitations of these techniques, there is a growing interest in exploring more direct approaches. The adaption of segmentation architectures originally designed for road extraction for medical imaging represents an innovative step in this direction. By employing K-space data as the modal input, this method completely eliminates the information loss inherent in FFT, thereby potentially enhancing the precision and effectiveness of glioma diagnosis. Methods: In the study, a novel architecture based on a deep-residual U-net was developed to accomplish the challenging task of automatically segmenting brain tumors from K-space data. Brain tumors from K-space data with different under-sampling rates were also segmented to verify the clinical application of our method. Results: Compared to the benchmarks set in the 2018 Brain Tumor Segmentation (BraTS) Challenge, our proposed architecture had superior performance, achieving Dice scores of 0.8573, 0.8789, and 0.7765 for the whole tumor (WT), tumor core (TC), and enhanced tumor (ET) regions, respectively. The corresponding Hausdorff distances were 2.5649, 1.6146, and 2.7187 for the WT, TC, and ET regions, respectively. Notably, compared to traditional image-based approaches, the architecture also exhibited an improvement of approximately 10% in segmentation accuracy on the K-space data at different under-sampling rates. Conclusions: These results show the superiority of our method compared to previous methods. The direct performance of lesion segmentation based on K-space data eliminates the time-consuming and tedious image reconstruction process, thus enabling the segmentation task to be accomplished more efficiently.

Enzyme entrapped in polymer-modified nanopores: the effects of macromolecular crowding and surface hydrophobicity.

Macromolecular crowding is an ubiquitous phenomenon in living cells that significantly affects the function of enzymes in vivo. However, this effect has not been paid much attention in the research of the immobilization of enzymes onto mesoporous silica. Herein, we report the combined effects of macromolecular crowding and surface hydrophobicity on the performance of an immobilized enzyme by accommodating lipase molecules into a series of mesoporous silicas with different amounts of inert poly(methacrylate) (PMA) covalently anchored inside the nanopores. The incorporation of the PMA polymer into the nanopores of mesoporous silica enables the fabrication of a crowded and hydrophobic microenvironment for the immobilized enzyme and the variation in polymer content facilitates an adjustment of the degree of crowding and surface properties of this environment. Based on this system, the catalytic features of immobilized lipase were investigated as a function of polymer content in nanopores and the results indicated that the catalytic efficiency, thermostability, and reusability of immobilized lipase could all be improved by taking advantage of the macromolecular crowding effect and surface hydrophobicity. These findings provide insight into the possible functions of the macromolecular crowding effect, which should be considered and integrated into the fabrication of suitable mesoporous silicas to improve enzyme immobilization.

Effects of Zn2+ and Pb2+ dopants on the activity of Ga2O3-based photocatalysts for water splitting.

Zn-doped and Pb-doped ß-Ga2O3-based photocatalysts were prepared by an impregnation method. The photocatalyst based on the Zn-doped ß-Ga2O3 shows a greatly enhanced activity in water splitting while the Pb-doped ß-Ga2O3 one shows a dramatic decrease in activity. The effects of Zn(2+) and Pb(2+) dopants on the activity of Ga2O3-based photocatalysts for water splitting were investigated by HRTEM, XPS and time-resolved IR spectroscopy. A ZnGa2O4-ß-Ga2O3 heterojunction is formed in the surface region of the Zn-doped ß-Ga2O3 and a slower decay of photogenerated electrons is observed. The ZnGa2O4-ß-Ga2O3 heterojunction exhibits type-II band alignment and facilitates charge separation, thus leading to an enhanced photocatalytic activity for water splitting. Unlike Zn(2+) ions, Pb(2+) ions are coordinated by oxygen atoms to form polyhedra as dopants, resulting in distorted surface structure and fast decay of photogenerated electrons of ß-Ga2O3. These results suggest that the Pb dopants act as charge recombination centers expediting the recombination of photogenerated electrons and holes, thus decreasing the photocatalytic activity.