Prediction of clear cell renal cell carcinoma ≤ 4cm: visual assessment of ultrasound characteristics versus ultrasonographic radiomics analysis.

Objective: To investigate the diagnostic efficacy of the clinical ultrasound imaging model, ultrasonographic radiomics model, and comprehensive model based on ultrasonographic radiomics for the differentiation of small clear cell Renal Cell Carcinoma (ccRCC) and Renal Angiomyolipoma (RAML). Methods: The clinical, ultrasound, and contrast-enhanced CT(CECT) imaging data of 302 small renal tumors (maximum diameter ≤ 4cm) patients in Tianjin Medical University Cancer Institute and Hospital from June 2018 to June 2022 were retrospectively analyzed, with 182 patients of ccRCC and 120 patients of RAML. The ultrasound images of the largest diameter of renal tumors were manually segmented by ITK-SNAP software, and Pyradiomics (v3.0.1) module in Python 3.8.7 was applied to extract ultrasonographic radiomics features from ROI segmented images. The patients were randomly divided into training and internal validation cohorts in the ratio of 7:3. The Random Forest algorithm of the Sklearn module was applied to construct the clinical ultrasound imaging model, ultrasonographic radiomics model, and comprehensive model. The efficacy of the prediction models was verified in an independent external validation cohort consisting of 69 patients, from 230 small renal tumor patients in two different institutions. The Delong test compared the predictive ability of three models and CECT. Calibration Curve and clinical Decision Curve Analysis were applied to evaluate the model and determine the net benefit to patients. Results: 491 ultrasonographic radiomics features were extracted from 302 small renal tumor patients, and 9 ultrasonographic radiomics features were finally retained for modeling after regression and dimensionality reduction. In the internal validation cohort, the area under the curve (AUC), sensitivity, specificity, and accuracy of the clinical ultrasound imaging model, ultrasonographic radiomics model, comprehensive model, and CECT were 0.75, 76.7%, 60.0%, 70.0%; 0.80, 85.6%, 61.7%, 76.0%; 0.88, 90.6%, 76.7%, 85.0% and 0.90, 92.6%, 88.9%, 91.1%, respectively. In the external validation cohort, AUC, sensitivity, specificity, and accuracy of the three models and CECT were 0.73, 67.5%, 69.1%, 68.3%; 0.89, 86.7%, 80.0%, 83.5%; 0.90, 85.0%, 85.5%, 85.2% and 0.91, 94.6%, 88.3%, 91.3%, respectively. The DeLong test showed no significant difference between the clinical ultrasound imaging model and the ultrasonographic radiomics model (Z=-1.287, P=0.198). The comprehensive model showed superior diagnostic performance than the ultrasonographic radiomics model (Z=4. 394, P<0.001) and the clinical ultrasound imaging model (Z=4. 732, P<0.001). Moreover, there was no significant difference in AUC between the comprehensive model and CECT (Z=-0.252, P=0.801). Both in the internal and external validation cohort, the Calibration Curve and Decision Curve Analysis showed a better performance of the comprehensive model. Conclusion: It is feasible to construct an ultrasonographic radiomics model for distinguishing small ccRCC and RAML based on ultrasound images, and the diagnostic performance of the comprehensive model is superior to the clinical ultrasound imaging model and ultrasonographic radiomics model, similar to that of CECT.

Rigid facial motion at study facilitates the holistic processing of own-race faces during the structural encoding stage.

Holistic processing is a fundamental element of face-recognition studies. Some behavioral studies have investigated the impact of rigid facial motion on holistic face processing, yet it is still unclear how rigid motion affects the time course of holistic face processing for different face races. The current study investigated this issue, using the composite face effect (CFE) as a direct measure of holistic processing. Participants were asked to match the identity of the top half of a static composite face with the study face during the test stage, where the study face was either static or rigidly-moving. ERP results showed that rigidly-moving study faces elicited a larger CFE relative to static study faces in the N170 component when recognizing own-race faces. The amplitude of P1, N170 and P2 components indicated that rigid motion facilitated holistic face processing, with differences observed between the hemispheres over time. Specifically, the CFE was only observed after exposure to rigidly-moving faces in the P1 and P2 components of the right hemisphere. Additionally, a greater CFE was observed following exposure to rigidly-moving faces compared to static faces, particularly in the N170 component of the left hemisphere. This study suggests that holistic processing is a fundamental aspect of face perception that applies to both static and moving faces, not just static ones. Furthermore, rigid facial motion improves holistic processing of own-race faces during the structural encoding stage. These findings provide evidence of distinct neural mechanisms underlying the holistic processing of static and moving faces.

Effect of Stroke Etiology on Endovascular Treatment for Acute Basilar-Artery Occlusion: A Post Hoc Analysis of the ATTENTION Randomized Trial.

BACKGROUND: Stroke etiology could influence the outcomes in patients with basilar-artery occlusion (BAO). This study aimed to evaluate the differences in efficacy and safety of best medical treatment (BMT) plus endovascular treatment (EVT) versus BMT alone in acute BAO across different stroke etiologies. METHODS: The study was a post hoc analysis of the ATTENTION trial (Trial of Endovascular Treatment of Acute Basilar-Artery Occlusion), which was a multicenter, randomized trial at 36 centers in China from February 2021 to September 2022. Patients with acute BAO were classified into 3 groups according to stroke etiology (large-artery atherosclerosis [LAA], cardioembolism, and undetermined cause/other determined cause [UC/ODC]). The primary outcome was a favorable outcome (modified Rankin Scale score of 0-3) at 90 days. Safety outcomes included symptomatic intracranial hemorrhage and 90-day mortality. RESULTS: A total of 340 patients with BAO were included, 150 (44.1%) had LAA, 72 (21.2%) had cardioembolism, and 118 (34.7%) had UC/ODC. For patients treated with BMT plus EVT and BMT alone, respectively, the rate of favorable outcome at 90 days was 49.1% and 23.8% in the LAA group (odds ratio, 3.08 [95% CI, 1.38-6.89]); 52.2% and 30.8% in the cardioembolism group (odds ratio, 2.45 [95% CI, 0.89-6.77]); and 37.5% and 17.4% in the UC/ODC group (odds ratio, 2.85 [95% CI, 1.16-7.01]), with P=0.89 for the stroke etiology×treatment interaction. The rate of symptomatic intracranial hemorrhage in EVT-treated patients with LAA, cardioembolism, and UC/ODC was 8.3%, 2.2%, and 3.2%, respectively, and none of the BMT-treated patients. Lower 90-day mortality was observed in patients with EVT compared with BMT alone across 3 etiology groups. CONCLUSIONS: Among patients with acute BAO, EVT compared with BMT alone might be associated with favorable outcomes and lower 90-day mortality, regardless of cardioembolism, LAA, or UC/ODC etiologies. The influence of stroke etiology on the benefit of EVT should be explored by further trials. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT04751708.

Design, synthesis and biological evaluation of novel SIRT3 inhibitors targeting both NAD+ and substrate binding sites for the treatment of acute myeloid leukemia.

Acute myeloid leukemia (AML) represents a highly malignant subtype of leukemia with limited therapeutic options. In this study, we propose a novel therapeutic strategy for treating AML by inhibiting SIRT3 to regulate mitochondrial metabolism network involved in energy metabolism and epigenetic modifications essential for AML survival. A series of thieno [3,2-d]pyrimidine-6-carboxamide derivatives were designed and synthesized by structure-based strategy, 17f was documented to be a potent and acceptable selective SIRT3 inhibitor with IC50 value of 0.043 µM and exhibited profound anti-proliferative activity in MOLM13, MV4-11, and HL-60 cells. Through CETSA assay and the degree of deacetylation of intracellular SIRT3 substrates, we confirmed that 17f could effectively bind and inhibit SIRT3 activity in AML cells. Mechanistically, 17f suppressed mitochondrial function, triggered the accumulation of ROS, and significantly inhibited the production of ATP in AML cells. With the breakdown of mitochondrial function, 17f eventually induced apoptosis of AML cells. In addition, 17f also showed excellent anti-AML potential in nude mouse tumor models of HL-60-Luc. Collectively, these results demonstrate that 17f is a potent and acceptable selective SIRT3 inhibitor with promising potential to treat AML.

G-MBRMD: Lightweight liver segmentation model based on guided teaching with multi-head boundary reconstruction mapping distillation.

BACKGROUND AND OBJECTIVES: Liver segmentation is pivotal for the quantitative analysis of liver cancer. Although current deep learning methods have garnered remarkable achievements for medical image segmentation, they come with high computational costs, significantly limiting their practical application in the medical field. Therefore, the development of an efficient and lightweight liver segmentation model becomes particularly important. METHODS: In our paper, we propose a real-time, lightweight liver segmentation model named G-MBRMD. Specifically, we employ a Transformer-based complex model as the teacher and a convolution-based lightweight model as the student. By introducing proposed multi-head mapping and boundary reconstruction strategies during the knowledge distillation process, Our method effectively guides the student model to gradually comprehend and master the global boundary processing capabilities of the complex teacher model, significantly enhancing the student model's segmentation performance without adding any computational complexity. RESULTS: On the LITS dataset, we conducted rigorous comparative and ablation experiments, four key metrics were used for evaluation, including model size, inference speed, Dice coefficient, and HD95. Compared to other methods, our proposed model achieved an average Dice coefficient of 90.14±16.78%, with only 0.6 MB memory and 0.095 s inference speed for a single image on a standard CPU. Importantly, this approach improved the average Dice coefficient of the baseline student model by 1.64% without increasing computational complexity. CONCLUSION: The results demonstrate that our method successfully realizes the unification of segmentation precision and lightness, and greatly enhances its potential for widespread application in practical settings.

Iterative Chebyshev approximation method for optimal control problems.

We present a novel numerical approach for solving nonlinear constrained optimal control problems (NCOCPs). Instead of directly solving the NCOCPs, we start by linearizing the constraints and dynamic system, which results in a sequence of sub-problems. For each sub-problem, we use finite number of Chebyshev polynomials to estimate the control and state vectors. To eliminate the errors at non-collocation points caused by conventional collocation methods, we additionally estimate the coefficient functions involved in the linear constraints and dynamic system by Chebyshev polynomials. By leveraging the characteristics of Chebyshev polynomials, the approximate sub-problem is changed into an equivalent nonlinear optimization problem with linear equality constraints. Consequently, any feasible point of the approximate sub-problem will satisfy the constraints and dynamic system throughout the entire time scale. To validate the efficacy of the new method, we solve three examples and assess the accuracy of the method through the computation of its approximation error. Numerical results obtained show that our approach achieves lower approximation error when compared to the Chebyshev pseudo-spectral method. The proposed method is particularly suitable for scenarios that require high-precision approximation, such as aerospace and precision instrument production.

Spin-State Control in Dysprosium(III) Metallacrown Magnets via Thioacetal Modification.

Integrating controllable spin states into single-molecule magnets (SMMs) enables precise manipulation of magnetic interactions at a molecular level, but remains a synthetic challenge. Herein, we developed a 3d-4f metallacrown (MC) magnet [DyNi5(quinha)5(Clsal)2(py)8](ClO4) ⋅ 4H2O (H2quinha=quinaldichydroxamic acid, HClsal=5-chlorosalicylaldehyde) wherein a square planar NiII is stabilized by chemical stacking. Thioacetal modification was employed via post-synthetic ligand substitutions and yielded [DyNi5(quinha)5(Clsaldt)2(py)8](ClO4) ⋅ 3H2O (HClsaldt=4-chloro-2-(1,3-dithiolan-2-yl)phenol). Thanks to the additional ligations of thioacetal onto the NiII site, coordination-induced spin state switching (CISSS) took place with spin state altering from low-spin S=0 to high-spin S=1. The synergy of CISSS effect and magnetic interactions results in distinct energy splitting and magnetic dynamics. Magnetic studies indicate prominent enhancement of reversal barrier from 57 cm-1 to 423 cm-1, along with hysteresis opening and an over 200-fold increment in coercive field at 2 K. Ab initio calculations provide deeper insights into the exchange models and rationalize the relaxation/tunnelling pathways. These results demonstrate here provide a fire-new perspective in modulating the magnetization relaxation via the incorporation of controllable spin states and magnetic interactions facilitated by the CISSS approach.

Evaluation of image-pro plus assisted superb microvascular imaging for differential diagnosis of renal masses.

OBJECTIVE: Previous research on diagnostic assessment by superb microvascular imaging (SMI) were based on qualitative or semi-quantitative assessments of vascularity, which may be subjective and unrepeatable by different sonographers. This study aimed to evaluate diagnostic performance of SMI Image-pro Plus (IPP) based vascular index (VI) for malignant renal masses. METHOD: We retrospectively reviewed 222 masses in 214 patients who underwent SMI between August 2019 and August 2022 in our study. We evaluated the diagnostic performance of blood flow via Alder grade, VI based on both IPP and SMI. RESULTS: The kappa consistency of the Adler grade and VI for renal masses was classified among different observers were 0.765 and 0.824. The intra-observers correlation ecoefficiency (ICC) were 0.727 and 0.874. Benign renal masses were mainly Adler grade 0, grade I, and grade II, VI was 4.30 ± 4.27 (Range 0.98-16.42); while malignant masses were mainly Adler grade III, VI was 14.95 ± 10.94 (Range 0.79-56.89). VI was higher in malignant than benign masses (t = 15.638, P < 0.01). Among the malignant masses, the mean VI in clear cell renal cell carcinoma was higher than that in papillary renal cell carcinoma and chromophobe renal cell carcinoma (F = 30.659, P < 0.01). The sensitivity, specificity and accuracy of SMI were 80.00%, 71.15%, and 78.64%, respectively. The sensitivity, specificity, and accuracy were 60.59%, 88.46%, and 80.18% by using a VI of 7.95 as the cutoff value to identify malignant lesions from benign masses yielded. VI had better diagnostic efficiency than ultrasonic characteristics and Adler grade in benign and malignant differential diagnosis (Z = 4.851, P < 0.01; Z = 2.732, P < 0.01). CONCLUSION: VI was higher in malignant than benign in renal masses. In malignant masses, VI in CCRCC was higher than that in papillary renal cell carcinoma and ChRCC. As a noninvasive examination, it had important clinical significance in the differential diagnosis of renal masses. VI from IPP may assist sonographer in distinguish renal malignances as a quantitative tool for vascularity.

Preoperative Differentiation of HER2-Zero and HER2-Low from HER2-Positive Invasive Ductal Breast Cancers Using BI-RADS MRI Features and Machine Learning Modeling.

BACKGROUND: Accurate determination of human epidermal growth factor receptor 2 (HER2) is important for choosing optimal HER2 targeting treatment strategies. HER2-low is currently considered HER2-negative, but patients may be eligible to receive new anti-HER2 drug conjugates. PURPOSE: To use breast MRI BI-RADS features for classifying three HER2 levels, first to distinguish HER2-zero from HER2-low/positive (Task-1), and then to distinguish HER2-low from HER2-positive (Task-2). STUDY TYPE: Retrospective. POPULATION: 621 invasive ductal cancer, 245 HER2-zero, 191 HER2-low, and 185 HER2-positive. For Task-1, 488 cases for training and 133 for testing. For Task-2, 294 cases for training and 82 for testing. FIELD STRENGTH/SEQUENCE: 3.0 T; 3D T1-weighted DCE, short time inversion recovery T2, and single-shot EPI DWI. ASSESSMENT: Pathological information and BI-RADS features were compared. Random Forest was used to select MRI features, and then four machine learning (ML) algorithms: decision tree (DT), support vector machine (SVM), k-nearest neighbors (k-NN), and artificial neural nets (ANN), were applied to build models. STATISTICAL TESTS: Chi-square test, one-way analysis of variance, and Kruskal-Wallis test were performed. The P values <0.05 were considered statistically significant. For ML models, the generated probability was used to construct the ROC curves. RESULTS: Peritumoral edema, the presence of multiple lesions and non-mass enhancement (NME) showed significant differences. For distinguishing HER2-zero from non-zero (low + positive), multiple lesions, edema, margin, and tumor size were selected, and the k-NN model achieved the highest AUC of 0.86 in the training set and 0.79 in the testing set. For differentiating HER2-low from HER2-positive, multiple lesions, edema, and margin were selected, and the DT model achieved the highest AUC of 0.79 in the training set and 0.69 in the testing set. DATA CONCLUSION: BI-RADS features read by radiologists from preoperative MRI can be analyzed using more sophisticated feature selection and ML algorithms to build models for the classification of HER2 status and identify HER2-low. TECHNICAL EFFICACY: Stage 2.

Patients' perceptions of post-treatment factors that influenced skill use after cognitive-behavioral therapy for bulimia nervosa spectrum disorders.

OBJECTIVE: Deterioration rate among patients with bulimia-spectrum eating disorders (BN-EDs) after receiving enhanced cognitive-behavioral therapy (CBT-E) remains high. Previous studies identified body image concerns, environmental triggers, lack of social support, lack of resources, comorbidity, and discontinued skill use as predictors of deterioration. However, no studies have qualitatively explored patients' perceptions of how these factors influenced their skill use and led to deterioration after receiving outpatient CBT. METHODS: This study aimed to qualitatively explore (1) what post-treatment factors patients believe contributed to deterioration, and (2) whether patients continued to practice the CBT skills they learned from treatment and identify motivators and barriers to post-treatment skill use. Twelve participants who had previously completed 16 sessions of CBT for their BN-EDs and experienced at least modest treatment responses participated in the qualitative interviews. RESULTS: Four themes were identified from the qualitative interviews. Post-treatment deterioration was primarily driven by decreased skill use due to a perceived sudden loss of accountability and continued body dissatisfaction after treatment ended. Discontinued practice of binge analysis led to decreased awareness of the relationship between poor skill use and ED behaviors. Difficulty accessing resources impeded participants from receiving external help to address challenges in skill practice, thus also contributing to deterioration. DISCUSSION: Findings suggested that outpatient treatment for BN-EDs patients should emphasize more on body image concern, and deterioration prevention for outpatient CBT-E should focus on building self-accountability to keep practicing skills after treatment ends. PUBLIC SIGNIFICANCE: This study was the first to qualitatively explore post-treatment factors influencing skill use and deterioration in patients with bulimia-spectrum eating disorders after they completed outpatient CBT. Findings indicated that decreased skill use was a primary driver of post-treatment deterioration, and that relapse prevention for outpatient CBT for BN-EDs should focus on enhancing patients' self-accountability to continue practicing therapeutic skills independently after treatment ended.

Neurosonological Parameters May Predict the Risk of Cerebral Hyperperfusion Syndrome After Carotid Artery Stenting.

OBJECTIVE: Cerebral hyperperfusion syndrome (CHS) is a critical complication in patients who underwent carotid artery stenting (CAS). We sought to explore neurosonological parameters and additional risk factors associated with CHS in patients following CAS and further to develop a prediction model for CHS after CAS. METHODS: A total of 197 patients who underwent CAS were included in this observational study. All patients were divided into CHS and non-CHS groups. Demographic, clinical, treatment, and laboratory data were extracted from electronic medical records. Logistic regression analysis and nomogram listing were used to build a CHS prediction model. Machine learning algorithms with five-fold cross-validation were used to further validate the CHS prediction model. RESULTS: Twenty-two patients had clinically manifested CHS. Four parameters were detected as risk factors associated with CHS, including effective collateral circulation (P = 0.046), asymmetry ratio of peak systolic velocity of the middle cerebral artery (P = 0.001), severe stenosis or occlusion of the contralateral carotid artery (P = 0.010), and low-density lipoprotein cholesterol (P = 0.025). The area under the curve for the prediction model of CHS in the cohort was 0.835 (95% confidence interval 0.760-0.909). CONCLUSIONS: In this study, CHS following CAS was associated with effective collateral circulation, ARP, contralateral ICA severe stenosis or occlusion, as well as low-density lipoprotein cholesterol. Subsequently, the CHS prediction model for CAS was built, which has the potential to facilitate tailored and precise management as well as treatment strategies for patients at high risk of CHS.

Aggregation induced emission dynamic chiral europium(III) complexes with excellent circularly polarized luminescence and smart sensors.

The synthesis of dynamic chiral lanthanide complex emitters has always been difficult. Herein, we report three pairs of dynamic chiral EuIII complex emitters (R/S-Eu-R-1, R = Et/Me; R/S-Eu-Et-2) with aggregation-induced emission. In the molecular state, these EuIII complexes have almost no obvious emission, while in the aggregate state, they greatly enhance the EuIII emission through restriction of intramolecular rotation and restriction of intramolecular vibration. The asymmetry factor and the circularly polarized luminescence brightness are as high as 0.64 (5D0 → 7F1) and 2429 M-1cm-1 of R-Eu-Et-1, achieving a rare double improvement. R-Eu-Et-1/2 exhibit excellent sensing properties for low concentrations of CuII ions, and their detection limits are as low as 2.55 and 4.44 nM, respectively. Dynamic EuIII complexes are constructed by using chiral ligands with rotor structures or vibration units, an approach that opens a door for the construction of dynamic chiral luminescent materials.

Determination of α-Dicarbonyl compounds in traditional Chinese herbal medicines.

α-DCs (α-dicarbonyls) have been proven to be closely related to aging and the onset and development of many chronic diseases. The wide presence of this kind of components in various foods and beverages has been unambiguously determined, but their occurrence in various phytomedicines remains in obscurity. In this study, we established and evaluated an HPLC-UV method and used it to measure the contents of four α-DCs including 3-deoxyglucosone (3-DG), glyoxal (GO), methylglyoxal (MGO), and diacetyl (DA) in 35 Chinese herbs after they have been derivatized with 4-nitro-1,2-phenylenediamine. The results uncover that 3-DG is the major component among the α-DCs, being detectable in all the selected herbs in concentrations ranging from 22.80 µg/g in the seeds of Alpinia katsumadai to 7032.75 µg/g in the fruit of Siraitia grosuenorii. The contents of the other three compounds are much lower than those of 3-DG, with GO being up to 22.65 µg/g, MGO being up to 55.50 µg/g, and DA to 18.75 µg/g, respectively. The data show as well the contents of the total four α-DCs in the herbs are generally in a comparable level to those in various foods, implying that herb medicines may have potential risks on human heath in view of the α-DCs.

Different anion (NO3- and OAc-)-controlled construction of dysprosium clusters with different shapes.

The complex hydrolysis process and strong uncertainty of self-assembly rules have led to the precise synthesis of lanthanide clusters still being in the "blind-box" stage and simplifying the self-assembly process and developing reliable regulation strategies have attracted widespread attention. Herein, different anions are used to induce the construction of a series of dysprosium clusters with different shapes and connections. When the selected anion is NO3-, it blocks the coordination of metal sites around the cluster through the terminal group coordination mode, thereby controlling the growth of the cluster. When NO3- was changed to OAc-, OAc- adopted a bridging mode to induce modular units to build dysprosium clusters through an annular growth mechanism. Specifically, we selected 2-amino-6-methoxybenzoic acid, 2-hydroxybenzaldehyde, and Dy(NO3)3·6H2O to react under solvothermal conditions to obtain a pentanuclear dysprosium cluster (1). The five Dy(III) ions in 1 are distributed in upper and lower planes and are formed by the tight connection of nitrogen and oxygen atoms, and µ3-OH- bridges on the ligand. Next, octa-nuclear dysprosium cluster (2) were obtained by only regulating ligand substituents. The eight Dy(III) ions in 2 are tightly connected through ligand oxygen atoms, µ2-OH-, and µ3-OH- bridges, forming an elliptical {Dy/O} cluster core. Furthermore, only by changing NO3- to OAc-, a wheel-shaped tetradeca-nuclear dysprosium cluster (3) was obtained. Cluster 3 is composed of OAc- bridged multiple template Dy3L3 units and pulling of these template units connected by an annular growth mechanism forms a wheel-shaped cluster. The angle of the coordination site on NO3- is ∠ONO = 115°, which leads to the further extension of the metal sites on the periphery of clusters 1 and 2 through the terminal group coordination mode, thereby regulating the structural connection of the clusters. However, the angle of the coordination site on OAc- is ∠OCO = 128°, and a slightly increased angle leads to the formation of a ring-shaped cluster 3 by connecting the template units through bridging. This is a rare example of the controllable construction of lanthanide clusters with different shapes induced by the regulation of different anions, which provides a new method for the precise construction of lanthanide clusters with special shapes.

Re-investigation of in vitro activity of acetohydroxyacid synthase I holoenzyme from Escherichia coli.

Acetohydroxyacid synthase (AHAS) is one of the key enzymes of the biosynthesis of branched-chain amino acids, it is also an effective target for the screening of herbicides and antibiotics. In this study we present a method for preparing Escherichia coli AHAS I holoenzyme (EcAHAS I) with exceptional stability, which provides a solid ground for us to re-investigate the in vitro catalytic properties of the protein. The results show EcAHAS I synthesized in this way exhibits similar function to Bacillus subtilis acetolactate synthase in its catalysis with pyruvate and 2-ketobutyrate (2-KB) as dual-substrate, producing four 2-hydroxy-3-ketoacids including (S)-2-acetolactate, (S)-2-aceto-2-hydroxybutyrate, (S)-2-propionyllactate, and (S)-2-propionyl-2-hydroxybutyrate. Quantification of the reaction indicates that the two substrates almost totally consume, and compound (S)-2-aceto-2- hydroxybutyrate forms in the highest yield among the four major products. Moreover, the protein also condenses two molecules of 2-KB to furnish (S)-2-propionyl-2-hydroxybutyrate. Further exploration manifests that EcAHAS I ligates pyruvate/2-KB and nitrosobenzene to generate two arylhydroxamic acids N-hydroxy-N-phenylacetamide and N-hydroxy-N-phenyl- propionamide. These findings enhance our comprehension of the catalytic characteristics of EcAHAS I. Furthermore, the application of this enzyme as a catalyst in construction of C-N bonds displays promising potential.

Production and release of 2-MIB in Pseudanabaena: Effects of growth phases on cell characteristics and 2-MIB yield.

2-methylisoborneol (2-MIB), a secondary metabolite produced by cyanobacteria, often causes a musty odour in water, threatening the safety of drinking water supplies. This study investigated the effects of the growth phases on the production of 2-MIB by Pseudanabaena. The effects of cell characteristics on the production and release of 2-MIB were also explored. The total 2-MIB concentration increased during the exponential phase and decreased during the declining phase, which was consistent with the changes in cell density. However, the total 2-MIB yield (1.12-1.27 fg cell-1) of Pseudanabaena did not significantly differ throughout the growth cycle (p > 0.05). Meanwhile, the extracellular 2-MIB yield increased significantly from 0.31 fg cell-1 in the exponential phase to 0.76 fg cell-1 in the declining phase (p < 0.05), and the corresponding proportion of extracellular 2-MIB improved from 25.13% to 59.16% (p < 0.05). The surge in extracellular 2-MIB during the declining phase could be attributed to the breaking of the Pseudanabaena filament, as indicated by the decrease in Dmean during cell ageing. The findings of this study contribute to a more inclusive comprehension and management of musty odour issues resulting from cyanobacteria in the water supply.

Neural manifestation of L2 novel concept acquisition from multi-contexts via both episodic memory and semantic memory systems.

This study aims to examine the process of L2 novel word learning through the combination of episodic and semantic memory, and how the process differs between the formation of thematic and taxonomic relations. The major approach adopted was observing the neural effects of word learning, which is manifested in the N400 from event-related potentials (ERPs). Eighty-eight participants were recruited for the experiment. In the learning session, L2 contextual discourses related to novel words were learned by participants. In the testing session, discourses embedded with incongruous and congruous novel words in the final position were used for participants to judge the congruency which affected the N400 neural activity. The results showed that both recurrent and new-theme discourses elicited significant N400 effects, while taxonomic sentences did not. These results confirmed the formation of episodic and semantic memory during L2 new word learning, in which semantic memory was mainly supported by thematic relations.

Influence of algal organic matter in the in-situ flotation removal of Microcystis using positively charged bubbles.

Positively charged bubbles efficiently capture and remove negatively charged algal cells without relying on coagulation-flocculation. However, the efficiency is notably influenced by the presence of algal organic matter (AOM). This study investigated the impact of AOM composition on flotation performance by analyzing AOM from various growth phases of Microcystis flos-aquae. The results indicated that low-concentration AOM (<5 mg C L-1), particularly the high molecular weight (>30 kDa) fractions containing high percentages of protein during the exponential growth phase, significantly improved the flotation efficiency by >18%. A high-speed camera system illustrates the pivotal role of low-concentration protein-containing AOM in forming network structures that enhance cell capture. These protein-driven network structures, which enhance the flotation efficiency, provide valuable insights into the development of effective in-situ algal bloom prevention techniques.

Coordination recognition of differential template units of lanthanide chiral chain.

Coordination-driven self-assembly processes often produce remarkable structures. In particular, self-assembly processes mediated by chiral template units have provided research ideas for analyzing the formation of chiral macromolecules in living organisms. In this study, by regulating the proportion of reaction raw materials in the "one-pot" synthesis of lanthanide complexes, we constructed chiral template units with different coordination orientations. As a result, lanthanide chiral chains connected to different structures were obtained through the self-assembly process of coordination recognition. In particular, driven by coordination, chiral template units with codirectional coordination points (called cis configuration) coordinate solely with cis template units during the self-assembly process to obtain a one-dimensional (1D) chain R-1/S-1 with an "S"-shaped distribution. Moreover, chiral template units with reversed coordination sites (called trans configuration) and twisted chiral template units are connected solely to templates with the same configuration to form a 1D chain R-2/S-2 with an axial helix. A circular dichroism spectrum shows that R-1/S-1 and R-2/S-2 are two pairs of enantiomers. The controllable construction of these two differential 1D chains is of great significance for studying coordination recognition at the molecular level. To the best of our knowledge, this is the first study to construct a 1D lanthanide chain through the self-assembly process of coordination recognition. The assembly process of nucleotides to form a hierarchical structure is simulated. This work provides a vivid example of the controllable synthesis of lanthanide complexes with precise structures and offers a new perspective on the formation process of chiral macromolecules that simulates natural processes.

Interface Investigation on SiGe/Si Multilayer Structures: Influence of Different Epitaxial Process Conditions.

SiGe/Si multilayer is the core structure of the active area of gate-all-around field-effect transistors and semiconductor quantum computing devices. In this paper, high-quality SiGe/Si multilayers have been grown by a reduced-pressure chemical vapor deposition system. The effects of temperature, pressure, interface processing (dichlorosilane (SiH2Cl2, DCS) and hydrogen chloride (HCl)) on improving the transition thickness of SiGe to Si interfaces were investigated. The interface quality was characterized by transmission electron microscopy/atomic force microscopy/high-resolution X-ray diffraction methods. It was observed that limiting the migration of Ge atoms in the interface was critical for optimizing a sharp interface, and the addition of DCS was found to decrease the interface transition thickness. The change of the interfacial transition layer is not significant in the short treatment time of HCl. When the processing time of HCl is increased, the internal interface is optimized to a certain extent but the corresponding film thickness is also reduced. This study provides technical support for the acquisition of an abrupt interface and will have a very favorable influence on the performance improvement of miniaturized devices in the future.