Substitution pattern controlled charge transport in BN-embedded aromatics-based single molecule junctions.

The understanding of charge transport at a single molecule level is a prerequisite for the fabrication of molecular devices. Here, the relationship between molecular conductance, substitution pattern and stimuli response in BN-embedded aromatics was systematically investigated using the break junction technique. It was found that the para-phenylthioether-anchored BN molecule (p-BN-p) shows the highest conductance of 10-4.86G0, and the meta-phenylthioether-anchored BN molecule (m-BN-m) exhibits the lowest conductance which is lower than the instrument detection limit (<10-6.0G0). The m-BN-p and p-BN-m molecules, with both para- and meta-substituted anchor groups on two termini, show moderate conductances of 10-5.50G0 and 10-5.45G0, respectively. The conductance difference is interpreted as a distinct quantum interference effect caused by the substitution pattern of the anchoring groups. Notably, their conductance changes slightly upon coordination with a fluoride ion, in spite of the distinct change of their frontier orbital energy levels. These results demonstrate that, in addition to the frontier orbital energy levels, the anchors play an important role in the design of stimuli-responsive molecular electronic devices with a high on/off current ratio.

Bidentate Phosphine-Assisted Synthesis of an All-Alkynyl-Protected Ag74 Nanocluster.

Determining the total structure of metal nanoparticles is vital to understand their properties. In this work, the first all-alkynyl-protected Ag nanocluster, Ag74(C≡CPh)44, was synthesized and structurally characterized by single crystal diffraction. Ag atoms are arranged in a Ag4@Ag22@Ag48 three shell structure and all 44 phenylethynyl ligands coordinated with Ag in a µ3 mode. In spite of being absent in nanocluster, 31P NMR study reveals that bidentate phosphine first reacts with Ag(I) to form a dinuclear complex, from which Ag atoms are then released to phenylethynyl ligands. This phosphine mediated strategy may find general application in synthesis of alkynyl-protected Ag nanoclusters.

Development and validation of a model for predicting prolonged weaning from mechanical ventilation in patients with abdominal trauma.

BACKGROUND: This study aimed to develop and validate a model to predict the risk of prolonged weaning from mechanical ventilation in patients with abdominal trauma. METHODS: Patients with abdominal trauma were included and were divided into the training cohort and the validation cohort. The model was constructed using predictive factors identified by univariable and multivariable logistic regressions, and was validated by receiver operating characteristic curve, calibration curve, and decision curve analysis. Clinical outcomes were compared between model-stratified risk groups. RESULTS: In total,190 patients were included, with 133 in the training cohort and 57 in the validation cohort. Six predictive factors, the Acute Physiology and Chronic Health Evaluation II score, Injury Severity Score, Glasgow coma scale, total bilirubin, skeletal muscle index, and abdominal fat index, were identified and were included in the model. The model predicting prolonged weaning owned a good discrimination, had an excellent calibration, and exhibited a favorable net benefit within a reasonable range of threshold probabilities. Significant differences were shown in prolonged weaning and clinical outcomes between the high-risk and low-risk groups (P < .05). Multivariable Cox regression analysis showed that patients in the high-risk group had greater risk of 28-day mortality (P < .05). CONCLUSION: This study established a model to predict the risk of prolonged weaning from mechanical ventilation and clinical outcomes in patients with abdominal trauma. Skeletal muscle index was identified as one of independent risk factors of prolonged weaning. The findings offer valuable insights for respiratory management in patients with abdominal trauma.

Skeletal muscle density as a new predictor of abdominal infection in abdominal trauma patients.

BACKGROUND AND AIMS: Skeletal muscle density (SMD) is a valuable prognostic indicator in various conditions such as cancer, liver cirrhosis. Yet, the connection between SMD and intra-abdominal infection in individuals who have suffered abdominal injuries is still unclear. The purpose of this research is to examine how well SMD can predict intra-abdominal infection in patients who have suffered abdominal trauma. METHODS: Participants with abdominal injuries were included in this research from January 2015 to April 2023. Based on the sex-specific cut off values of SMD, the entire population was split into two categories. Prognostic factors were identified through logistic regression analysis. ROC was used to assess the predictive accuracy of SMD and its combinations with other biomarkers for clinical outcomes. RESULTS: A total of 220 patients were ultimately included in the study. Patients in the group with low SMD exhibited a higher incidence of intra-abdominal infection, longer hospital stays, and increased hospital costs. In patients with abdominal trauma, low SMD was identified as a significant independent predictor of intra-abdominal infection (OR 2.397; 95 % CI 1.117-5.141, p = 0.025). Low SMD had a higher area under the curve (AUC) in ROC analysis compared to TRF, NRS2002 score, and APACHEII score for predicting intra-abdominal infection (AUC 0.70, 95 % CI 0.61-0.78, p = 0.002). Moreover, low SMD showed associations with clinical outcomes such as hospital stay length and costs (p < 0.01). CONCLUSIONS: Low SMD is recognized as an independent risk factor for predicting intra-abdominal infections in this patient population. Notably, SMD is emerging as a novel predictor of abdominal infections in patients with abdominal trauma.

Interpretable Machine Learning of Two-Photon Absorption.

Molecules with strong two-photon absorption (TPA) are important in many advanced applications such as upconverted laser and photodynamic therapy, but their design is hampered by the high cost of experimental screening and accurate quantum chemical (QC) calculations. Here a systematic study is performed by collecting an experimental TPA database with ≈900 molecules, analyzing with interpretable machine learning (ML) the key molecular features explaining TPA magnitudes, and building a fast ML model for predictions. The ML model has prediction errors of similar magnitude compared to experimental and affordable QC methods errors and has the potential for high-throughput screening as additionally validated with the new experimental measurements. ML feature analysis is generally consistent with common beliefs which is quantified and rectified. The most important feature is conjugation length followed by features reflecting the effects of donor and acceptor substitution and coplanarity.

Photochemical Synthesis of Atomically Precise Ag Nanoclusters.

Photochemical methods are effective for controllable synthesis of silver nanoparticles with specific sizes and shapes. Whether they are capable of fabricating Ag nanoclusters (NCs) with atomic precision is yet to be proved. In this work, we synthesize an atomically precise Ag NC, [Ag25(4-MePhC≡C)20(Dpppe)3](SbF6)3 (Ag25), via a process mediated by visible light. Its total structure is determined by X-ray crystallography. The investigation of the mechanism reveals that the formation of Ag25 is triggered by a photoinduced electron-transfer (PET) process. An electron of certain amines is excited by light with wavelength shorter than 455 nm and transferred to Ag+. The amine is oxidized to the corresponding amine N-oxide. Such a PET process is supported by experimental and density functional theory studies. To expand the application scope of the photochemical method, another three NCs, [Ag19(4-tBuPhC≡C)14(Dpppe)3](SbF6)3 (Ag19), [Ag32(4-tBuPhC≡C)22(Dppp)4](SbF6)3 (Ag32), and bimetallic [Ag22Au3(4-tBuPhC≡C)20(Dpppe)3](SbF6)3 (Ag22Au3), are produced by replacing certain ingredients. Furthermore, since the formation of Ag19 can be regarded as a photochromatic process, a facile amine visual detection method is also presented based on this mechanism.

Birth defects data from hospital-based birth defect surveillance in Guilin, China, 2018-2020.

Objectives: Birth defects (BDs) are a major contributor to perinatal and infant mortality, morbidity and lifelong disability worldwide. A hospital-based study on birth defects was designed in Guilin city in the Guangxi province of Southwestern China aiming to determine the prevalence of BDs in the studied region, and the classify the BDs based on clinical presentation and causation. Methods: The study involved BDs among all pregnancy outcomes (live births, stillbirths, death within 7 days, and pregnancy terminations) born in the 42 registered hospitals of Guilin between 2018 and 2020. The epidemiological characteristics of BDs and the etiologic profile of BDs were evaluated in this study. Results: Of the total 147,817 births recorded during the study period, 2,003 infants with BDs were detected, giving a total prevalence rate of 13.55 per 1,000 births. The top five BD types were congenital heart defects, polydactyly, syndactyly, malformations of the external ear, and talipes equinovarus, whereas, neural tube defects, congential esophageal atresia, gastroschisis, extrophy of urinary bladder, were the least common BD types in these 3 years. Only 8.84% of cases were assigned a known etiology, while most cases (91.16%) could not be conclusively assigned a specific cause. Conclusion: This study provides an epidemiological description of BDs in Guilin, which may be helpful for understanding the overall situation in Southwest China of BDs and aid in more comprehensive studies of BDs in future healthcare systems, including funding investment, policy-making, monitor, prevention. Strong prevention strategies should be the priority to reduce BDs and improve the birth quality.

Improving occupational health for health workers in a pilot hospital by application of the HealthWISE international tool: An interview and observation study in China.

Objective: For a safe and healthy workplace in the health sector, the International Labor Organization (ILO) and the World Health Organization (WHO) jointly developed HealthWISE, an international technical tool that helps health workers (HWs) to identify workplace hazards and apply low-cost solutions. This study sought to gather experiences and lessons from a Chinese pilot hospital for the scale-up application of HealthWISE. Methods: A qualitative study was undertaken at a Chinese public hospital with a ≥5-year application of HealthWISE through in-depth interviews with targeted HWs who participated in the Training-of-Trainer (TOT) workshops, and observations were gathered using evidence from photos and publications, then, thematic analysis was formulated. Results: Driven by motivation, the participants learned from the HealthWISE TOT workshop alongside the favorite and worst parts of it. Positive changes and results of occupational health for HWs occurred after the workshop, the participants trained others and planned to implement HealthWISE within their responsibility. During the COVID-19 Pandemic, the Hospital acted the approaches of protecting the health, safety and well-being of HWs with significant results. Further suggestions on workshop and HealthWISE implementing as well as the national policies were collected. The study indicated the Hospital's experience of leadership and participation, supporting and facilitating, system establishment, and culture creation. The suggestion included keeping staff engaged under a positive safety and health culture, promoting recognition of HealthWISE among public health institutions nationwide, developing online courses for medical colleges, focusing on the alignment among various law systems, and adopting measures under the principle of the hierarchy of occupational hazards controls. Conclusion: This study has demonstrated the systematic improvement of occupational health for HWs by HealthWISE implementation in the Chinese hospital. The valuable experiences and lessons derived here can be shared with other hospitals in China and beyond, especially under the unprecedented challenges of the COVID-19 pandemic, to achieve the goals of safety, health, and well-being for HWs by building a resilient health system.

Low skeletal muscle mass predicts poor clinical outcomes in patients with abdominal trauma.

OBJECTIVE: The aim of this study was to investigate whether low skeletal muscle mass is associated with clinical outcomes in patients with abdominal trauma. METHODS: Patients presenting to our institution with abdominal trauma from January 2010 to April 2020 were retrospectively included. Low skeletal muscle mass was defined, using computed tomography, as skeletal muscle index (SMI) at the third lumbar vertebra below the lowest sex-specific quartile within 1 wk of admission. Clinical outcomes such as complications, hospital stay, and hospital cost were recorded, and univariate and multivariate analyses were performed. RESULTS: Among 684 patients, 451 were eligible. Of these, 112 (24.8%) were classified as having low skeletal muscle mass, based on SMI diagnostic cutoff values (42.08 cm2/m2 for men and 37.35 cm2/m2 for women). Low skeletal muscle mass was significantly associated with longer hospital length of stay, longer intensive care length of stay, higher cost, higher frequency of mechanical ventilation, longer duration of vasopressor use, and higher incidence of massive transfusion and overall complications (P < 0.05). Subgroup analysis showed that pneumonia, acute gastrointestinal dysfunction, cholecystitis, digestive tract fistula, gastric fistula, and intestinal fistula were significantly associated with low skeletal muscle mass (P < 0.05). Multivariate analysis showed that low skeletal muscle mass was an independent risk factor for overall complications (odds ratio [OR], 2.44; 95% confidence interval [CI], 1.33-4.49; P = 0.004), hospital length of stay (OR, 3.49; 95% CI, 1.96-6.20; P < 0.001), and hospital cost (OR, 2.67; 95% CI, 1.48-4.80; P = 0.001). CONCLUSIONS: Low skeletal muscle mass could be an independent predictor of poor clinical outcomes in patients with abdominal trauma.

Up-Regulation of miR-21 Expression Predicate Advanced Clinicopathological Features and Poor Prognosis in Patients with Non-Small Cell Lung Cancer.

MicroRNAs (miRNAs) are endogenous small (19-24 nt long) noncoding RNAs that regulate gene expression in a sequence specific manner. An increasing association between miRNA and cancer has been recently reported. Lung cancer is globally responsible for 1.4 million deaths annually and is the leading cause of cancer-related deaths in both women and men. In this study, we investigated the miR-21 expression in non-small cell lung cancer (NSCLC) to evaluate their value in prognosis of this tumor. Here, we assess miR-21 expression in NSCLC and its clinical significance including survival analysis. The expression of miR-21 in matched normal and tumor tissues of NSCLC was evaluated using a quantitative real-time RT-PCR. A Kaplan-Meier survival curve was generated following a logrank test. It was observed that miR-21 expression was up-regulated in NSCLC tissues compared with noncancerous lung tissues (mean ± SD: 6.7 ± 2.3 vs. 3.7 ± 1.5, P < 0.001). The up-regulation of miR-21 in NSCLC cancer tissues was also significantly correlated with aggressive clinicopathological features. We found that the patients with high miR-21 expression have a higher tumor grade (P = 0.027) and are in higher risk of lymph node metastasis (P = 0.021). Moreover, the results of Kaplan-Meier analyses showed that NSCLC patients with the high miR-21 expression tend to have shorter overall survival and progression free survival (P < 0.001). The multivariate analysis clearly indicated that the high miR-21 expression in biopsy samples may be considered as an independent prognostic factor in NSCLC for decreased survival (RR 3.88; 95%CI, 2.47-6.11). Our data indicate the potential of miR-21 as a novel prognostic biomarker for NSCLC. Large well-designed studies with diverse populations and functional evaluations are warranted to confirm and extend our findings.

Spectrofluorimetric determination of glutathione in human plasma by solid-phase extraction using graphene as adsorbent.

An efficient solid phase extraction-spectrofluorimetric method using graphene as adsorbent was developed to sensitively determine glutathione (GSH) in biological samples. Fluorescent probe N-(4,4-difluoro-5,7-dimethyl-4-bora-3a,4a-diaza-s-indacene-3-yl)methyl)iodoacetamide (BODIPY Fl-C1-IA) was applied for the derivatization of GSH. The procedure was based on BODIPY Fl-C1-IA selective reaction with GSH to form highly fluorescent product BODIPY Fl-C1-IA-GSH, its extraction to the graphene-packed SPE cartridge and spectrofluorimetric determination. Some factors affecting the extraction efficiency, such as the type of the eluent and its volume, sample pH, extraction time, and sample volume were optimized. Comparative studies were also performed between graphene and other adsorbents including C18 silica, graphitic carbon, and multi-walled carbon nanotubes for the extraction of analyte. The calibration graph using the pretreatment system for GSH was linear over the range of 0.5-200 nM. The limit of detection was 0.01 nM (signal-to-noise ratio=3). Relative standard deviation for six replicate determinations of GSH at 80 nM concentration level was lower than 5.0%. The developed method was applied to the determination of GSH in human plasma with recoveries of 92-108%. This work revealed the great potentials of graphene as an excellent sorbent material in the analysis of biological samples.

Development of an ionic liquid-based ultrasonic-assisted liquid-liquid microextraction method for sensitive determination of biogenic amines: application to the analysis of octopamine, tyramine and phenethylamine in beer samples.

A simple and efficient method, ionic liquid-based ultrasound-assisted liquid-liquid microextraction, has been developed for the determination of three biogenic amines including octopamine (OCT), tyramine (TYR) and phenethylamine (PHE). Fluorescence probe 2,6-dimethyl-4-quinolinecarboxylic acid N-hydroxysuccinimide ester was applied for derivatization of biogenic amines and high-performance liquid chromatography coupled with fluorescence detection was used for the determination of the derivatives. The factors affecting the extraction efficiency, such as the type and volume of ionic liquid, ultrasonication time and centrifugation time have been investigated in detail. Under the optimum conditions, linearity of the method was observed in the range of 0.5-50 µgmL(-1) for OCT and TYR, and 0.025-2.5 µgmL(-1) for PHE, respectively, with correlation coefficients (γ)>0.996. The limits of detection ranged from 0.25-50 ngmL(-1) (S/N=3). The spiked recoveries of three target compounds in beer samples were in the range of 90.2-114%. As a result, this method has been successfully applied for the sensitive determination of OCT, TYR and PHE in beer samples.

Enhanced sensing of dopamine in the present of ascorbic acid based on graphene/poly(p-aminobenzoic acid) composite film.

Graphene/p-aminobenzoic acid composite film modified glassy carbon electrode (Gr/p-ABA/GCE) was first employed for the sensitive determination of dopamine (DA). The electrochemical behavior of DA at the modified electrode was investigated by cyclic voltametry (CV), differential pulse voltametry (DPV) and amperometric curve. The oxidation peak currents of DA increased dramatically at Gr/p-ABA/GCE. The modified electrode was used to electrochemically detect dopamine (DA) in the presence of ascorbic acid (AA). The Gr/p-ABA composite film showed excellent electrocatalytic activity for the oxidation of DA in phosphate buffer solution (pH 6.5). The peak separation between DA and AA was large up to 220 mV. Using DPV technique, the calibration curve for DA determination was obtained in the range of 0.05-10 µM. The detection limit for DA was 20 nM. AA did not interfere with the determination of DA because of the very distinct attractive interaction between DA cations and the negatively Gr/p-ABA composite film. The proposed method exhibited good stability and reproducibility.

The investigation of the interactions between CdSe quantum dots and human serum albumin by resonance Rayleigh scattering and second-order scattering spectra.

Human serum albumin (HSA) was the most abundant protein in human plasma and has significant physiological function. In Tris-HCl buffer solution (pH 7.4), water-soluble semiconductor CdSe quantum dots (QDs) reacted with HSA and the products resulted in a great enhancement of the intensity of resonance Rayleigh scattering (RRS) and second-order scattering (SOS). Based on this, a new method was developed to investigate the interactions between QDs and HSA. The parameters with regard to determination were optimized, and the reaction mechanism was discussed. Under optimal conditions, the increments of scattering intensity (DeltaI) were directly proportional to the concentrations of HSA in the range of 0.4-48.0 micromol L(-1). The detection limits were 0.10 micromol L(-1) for RRS method and 0.25 micromol L(-1) for SOS method. The proposed method was sensitive, simple and rapid. It has been successfully applied to the determination of HSA in human urine samples. Analytical results obtained with this novel assay were satisfactory.

Ultrasound-assisted dispersive liquid-liquid microextraction combined with high-performance liquid chromatography-fluorescence detection for sensitive determination of biogenic amines in rice wine samples.

Ultrasound-assisted dispersive liquid-liquid microextraction coupled with high-performance liquid chromatography-fluorescence detection was used for the extraction and determination of three biogenic amines including octopamine, tyramine and phenethylamine in rice wine samples. Fluorescence probe 2,6-dimethyl-4-quinolinecarboxylic acid N-hydroxysuccinimide ester was applied for derivatization of biogenic amines. Acetonitrile and 1-octanol were used as disperser solvent and extraction solvent, respectively. Extraction conditions including the type of extraction solvent, the volume of extraction solvent, ultrasonication time and centrifuging time were optimized. After extraction and centrifuging, analyte was injected rapidly into high-performance liquid chromatography and then detected with fluorescence. The calibration graph of the proposed method was linear in the range of 5-500 microg mL(-1) (octopamine and tyramine) and 0.025-2.5 microg mL(-1) (phenethylamine). The relative standard deviations were 2.4-3.2% (n=6) and the limits of detection were in the range of 0.02-5 ng mL(-1). The method was applied to analyze the rice wine samples and spiked recoveries in the range of 95.42-104.56% were obtained. The results showed that ultrasound-assisted dispersive liquid-liquid microextraction was a very simple, rapid, sensitive and efficient analytical method for the determination of trace amount of biogenic amines.