Research on the prediction model of energy separation effect of vortex tube based on trajectory deflection characteristics and its numerical solution method.

In this paper, in order to establish the energy separation mechanism of the vortex tube, the hydrodynamic behavior of the compressible fluid in the asymmetric cavity space is investigated, and a numerical model of the trajectory deflection behavior is deduced and established; in order to form the optimal design method of the structural parameters of the vortex tube, the force situation of the fluid microelements entering different regions of the vortex chamber of the vortex tube is analyzed, and the trajectory deflection equations are corrected by combining with the expansion behavior of the fluid and the characterizing equations of vortex strength, transportability, and vortex initiation characteristics are given. The characterization equations of vortex strength, transportability and vortex initiation characteristics are given, and the numerical simulation of their influence parameters is carried out; in order to realize the prediction of the vortex tube performance of a given structure, the multifactor Pearson thermodynamic map is used to correlate and analyze the experimental data of vortex tubes reported publicly in the past years, and the polynomial regression equations are designed and established for the prediction of the vortex tube's energy separation effect and the confidence level and the degree of coincidence of the prediction results are examined. The confidence level and degree of agreement of the prediction results were examined. It is found that: the trajectory deflection motion of the compressible fluid in the asymmetric cavity space is the result of the combined effect of structural air pressure bias and the expansion behavior of the incident fluid; in order to improve the vortex strength in the vortex tube, the vortex initiation chamber space should be as small as possible; the increase of the diameters of the hot-end pipe and the cold-end pipe is conducive to the enhancement of vortex strength, but at the same time, it weakens the vortex transport in the heat pipe; the vortex initiation chamber size has a negative correlation with the hot-end temperature rise, and the inlet fluid pressure has a The negative correlation between the size of the vortex chamber and the temperature rise at the hot end, the positive correlation between the increase of inlet fluid pressure and the resulting temperature rise, and the strong correlation between the inlet fluid pressure and the friction coefficient on the effect of energy separation; the predictive equations for the effect of energy separation obtained by the fitting are in good agreement with the real situation.

Newly graduated registered nurses' experiences of the pre-service safety training program: A qualitative study.

BACKGROUND: Patient safety is a top priority for the global healthcare system and a prerequisite for high-quality nursing care. In China, newly graduated registered nurses are required to receive two years of standardized training to ensure patient safety. The pre-service safety training program aims to provide safe, high-quality, and effective nursing care. However, perceptions and experiences of newly graduated registered nurses on pre-service safety training programs have not yet been explored. OBJECTIVES: To investigate newly graduated registered nurses' perceptions and experiences of the pre-service safety training program in a tertiary hospital in China. DESIGN: A phenomenological approach was used for this qualitative study. SETTINGS: Tertiary hospital in Shanghai, China. PARTICIPANTS: A total of 19 newly graduated registered nurses who participated in the pre-service safety training program. METHODS: Data were collected using semi-structured, face-to-face, in-depth interviews and analyzed using the Colaizzi seven-step framework. RESULTS: Three themes and nine sub-themes emerged: (1) satisfaction with the approaches and content of the training, (2) gaining benefits and growth, and (3) suggestions for the training. CONCLUSION: It is meaningful for newly graduated registered nurses to receive safety training before entering clinical practice and was praised by participants for helping them improve safety competence and change safety behaviors. Continuing safety training and optimizing the training modules and evaluation methods will maximize the effectiveness of safety training.

Exploring promotion factors of resilience among emergency nurses: a qualitative study in Shanghai, China.

OBJECTIVE: To qualitatively explore the factors that enhance resilience among emergency nurses (ENs). DESIGN: This study is an exploratory qualitative investigation. Semistructured in-depth interviews were used for data collection, while qualitative content analysis was applied for data analysis. SETTING: A grade A tertiary hospital in Shanghai, China. PARTICIPANTS: The study subjects comprised 17 ENs, who were selected using a purposive sampling method. RESULTS: Three main themes and the nine subthemes emerged from the study, that is, individual resources, including competency, personality traits and occupational benefits; family resources, including close parent-child attachment and supportive family dynamics; social resources, including peer support, organisational support, resilient leadership and popular support. CONCLUSION: This qualitative study explored the factors promoting resilience among ENs and provided a reference for managers to formulate future management strategies. From the perspective of positive psychology, nurses should receive comprehensive support, focusing on improving their professional accomplishment and role ability while prioritising the development of resilient leadership. These efforts are expected to drive progress and growth across the emergency care team.

Pain Catastrophizing Dimensions Mediate the Relationship between Chronic Pain Severity and Depression.

BACKGROUND: Although past studies have found significant positive correlations of both pain severity and overall pain catastrophizing (PC) levels with depression in chronic pain samples, less is known about the extent to which specific PC dimensions (i.e., helplessness, magnification, rumination) explain links between pain severity and depression. AIM: This study assessed the relative importance of PC dimensions as mediators of relations between chronic pain severity and depression. DESIGN: A cross sectional study design was employed. METHOD: Mainland Chinese adults with chronic pain (n = 983) completed validated questionnaire measures of PC, depression, and chronic pain severity within a cross-sectional research design. RESULTS: Analyses indicated helplessness mediated the association between pain severity and depression while magnification partially mediated the association of helplessness with depression. Conversely, rumination did not make a significant contribution in the mediation model. CONCLUSIONS: The helplessness dimension of PC, in particular, may help to explain why people with more severe chronic pain are prone to co-occurring depression.

Measurement of MMP-7 in micro-volume peripheral blood: development of dried blood spot approach.

Purpose: Serum matrix metalloproteinase-7 (MMP-7) is significant in differentiating biliary atresia (BA). This study aims to develop a new peripheral blood quantitative collection device to detect MMP-7 levels via dried blood spot (DBS). Methods: This is a diagnostic accuracy test. Serum and DBS MMP-7 concentrations were measured using an ELISA kit. Intraoperative cholangiography and subsequent histological examinations were used to confirm BA diagnoses. Results: A total of 241 infants with obstructive jaundice were enrolled, among whom 168 were BA. Linear regression showed DBS MMP-7 correlated well with serum MMP-7 (R = 0.93, P < 0.001). The best cut-off value of serum MMP-7 for BA was 25.9 ng/ml, achieving the area under the ROC curve (AUC) of 0.962 (95% CI: 0.941, 0.983), and the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were 86.9%, 94.5%, 97.3% and 75.8%, respectively. The best cut-off value of DBS MMP-7 for BA was 12.5 ng/ml, achieving the AUC of 0.922 (95% CI: 0.888, 0.956), and the sensitivity, specificity, PPV, and NPV were 86.9%, 89.0%, 94.8%, and 74.7%, respectively. The dried blood spots were intervened under different storage conditions, including 1-5 days at room temperature, 2 or 3 days at 30 °C and 2 or 3 days at 37 °C. The DBS MMP-7 concentration under different storage conditions had good correlation and consistency with that at -80 °C. Conclusions: Serum and DBS MMP-7 correlate well, both of which have high accuracy in the diagnosis of BA, while the requirements for the storage of DBS are low.

The resilience of emergency and critical care nurses: a qualitative systematic review and meta-synthesis.

Background: Due to the unique work environment, emergency and critical care departments nurses face high job pressure, often resulting in burnout and a high turnover rate. Public health emergencies such as the Corona Virus Disease 2019 pandemic tend to exacerbate these problems further. Therefore, improving the resilience of nurses is crucial to enhance their retention rates. Objective: This systematic review and meta-synthesis of qualitative studies on the resilience of emergency and critical nurses were conducted to provide a reference for clinical managers to develop strategies for improving the resilience of nurses. Methods: Following databases were searched for relevant studies: CINAHL Plus, Elsevier, Cochrane Library, Embase, Medline, OVID, Pubmed, Science Direct, LWW and Web of Science, China National Knowledge Network (CNKI), Wanfang Database (CECDB), VIP Database, and Sinomed. Google Scholar and Opengrey were used to search for gray literature. The literature search period was from the establishment of the database to April 2023. The systematic review of qualitative studies followed the Joanna Briggs Institute (JBI) approach, including critical appraisal using the JBI Checklist and synthesis through meta-synthesis. Confidence of evidence was assessed with JBI's ConQual process. Results: A total of 12 articles were identified, with 59 main results and 9 new integrated categories. Also, 3 themes, i.e., risk factors, protective factors, and personal growth, and 9 sub-themes, i.e., working pressure, negative emotion, an organizational issue, active learning, sense of occupational benefit, social support, self-cognition and regulation, learn to adapt, and self-actualization, were formed. Conclusion: The resilience of emergency and critical care nurses depends on various factors. Managers should prioritize the mental health of nurses and implement measures to enhance their resilience through social support, team building, and psychological capital development. Additionally, management models can be updated based on domestic and international experience to improve nurses' job involvement, optimize nursing quality, and promote the advancement of the nursing profession.

Non-invasive detection of haemoglobin, platelets, and total bilirubin using hyperspectral cameras.

Hyperspectral imaging has emerged as a promising high-resolution and real-time imaging technology with potential applications in medical diagnostics and surgical guidance. In this study, we developed a high-speed hyperspectral camera by integrating a Fabry-Perot cavity filter on each CMOS pixel. We used it to non-invasively detect three blood components (haemoglobin, platelet, and total bilirubin). Specifically, we acquired transmission images of the subject's fingers, extracted spectral signals at each wavelength, and used dynamic spectroscopy to obtain non-invasive blood absorption spectra. The prediction models were established using the PLSR method and were modelled and validated based on the standard clinical-biochemical test values. The experimental results demonstrated excellent performance. The best predictions were obtained for haemoglobin, with a high related coefficient (R) of 0.85 or more in both the calibration and prediction sets and a mean absolute percentage error (MAPE) of only 5.7%. The results for total bilirubin were also ideal, with R values exceeding 0.8 in both sets and a MAPE of 10.6%. Although the prediction results for platelets were slightly less satisfactory, the error was still less than 15%, indicating that the results were also acceptable. Overall, our study highlights the potential of hyperspectral imaging technology for the development of portable and affordable devices for blood analysis, which can be used in various settings.

Highly selective and sensitive benzopyran-based fluorescent probes for imaging exogenous and endogenous peroxynitrite.

Peroxynitrite is widely present in organisms and closely related to many pathophysiological functions. Therefore, it is of great physiological significance to develop capable probes for detecting ONOO-. In this work, a novel fluorescent probe B-Ch was designed based on the intramolecular charge transfer (ICT) effect. By means of molecular engineering, the replacement from diethylamine group to hydroxyl group has improved the detection sensitivity of the probe. After the addition of ONOO-, the solution color and fluorescence showed noticeable changes, which were visible to the naked eye. The probe showed excellent advantages: visualization, good selectivity, low sensitivity (22.4 nM), good stability and biocompatibility, exogenous and endogenous imaging of ONOO- in HeLa cells.

Visible-Light-Induced Radical Cascade Cross-Coupling via C(sp3)-H Activation and C-N/N-O Cleavage: Feasible Access to Methylenebisamide Derivatives.

Here we report facile and manipulable access to methylenebisamide derivatives via visible-light-driven radical cascade processes incorporating C(sp3)-H activation and C-N/N-O cleavage. Mechanistic studies reveal that a traditional Ir-catalyzed photoredox pathway and a novel copper-induced complex-photolysis pathway are both involved, contributing to activating the inert N-methoxyamides and rendering the valuable bisamides. This approach exhibits many advantages, including mild reaction conditions, broad scope and functional group tolerance, and competitive step economy. Given the mechanistic plenitude and operational simplicity, we believe this package deal paves a promising way for the synthesis of valuable nitrogen-containing molecules.

Individual Differences in Pain Catastrophizing and Regional Gray Matter Volume Among Community-dwelling Adults With Chronic Pain: A Voxel-based Morphology Study.

OBJECTIVES: Elevations in pain catastrophizing (PC) are associated with more severe pain, emotional distress, and impairment within samples with chronic pain. However, brain structure correlates underlying individual differences in PC are not well understood and predict more severe pain and impairment within samples with chronic pain. This study assessed links between regional gray matter volume (GMV) and individual differences in PC within a large mixed chronic pain sample. MATERIALS AND METHODS: Chinese adult community dwellers with chronic pain of at least 3 months duration (101 women and 59 men) completed self-report measures of background characteristics, pain severity, depression, and a widely validated PC questionnaire as well as a structural magnetic resonance imagining scan featuring voxel-based morphology to assess regional GMV correlates of PC. RESULTS: After controlling for demographic correlates of PC, pain severity, and depression, higher PC scores had a significant, unique association with lower GMV levels in the inferior temporal area of the right fusiform gyrus, a region previously implicated in emotion regulation. DISCUSSION: GMV deficits, particularly in right temporal-occipital emotion regulation regions, correspond to high levels of PC among individuals with chronic pain.

Spectral features of the ferrous-CO complex in cytochrome P450: a revisit using TDDFT calculations.

There are different views in the literature regarding how to interpret the observed spectral features of the ferrous-CO complexes in cytochrome P450 enzymes (P450s). In this work, we applied density functional theory (DFT) and time-dependent DFT (TDDFT) calculations at the B3LYP-D3BJ/def2-TZVP level with a CPCM correction to the ferrous-CO models of P450s as well as of proteins that contain a histidine-ligated heme. Our results support the notion derived from a previously reported iterative extended Hückel calculation that the involvement of the sulfur lone-pair orbital (S(nz)) of the axial cysteine ligand in the electronic excitations gives rise to a spectral anomaly. The Q and the shorter-wavelength Soret (B') peaks are primarily due to the electronic transitions from the a2u- and S(nz)-type molecular orbitals (MOs), generated via an orbital interaction of fragment orbitals, to the near-degenerate eg-type π* MOs, respectively. The transitions from the a1u-type MO to the eg-type MOs contribute most to the longer wavelength Soret (B) peaks. Both a2u- and S(nz)-type MOs contribute to the B peaks, but the contribution of the latter is greater. When the axial ligand is histidine, the Q and Soret peaks originate essentially from the excitations from the a2u- and a1u-type MOs to the eg-type MOs. The transitions from the b2u-type MOs to the eg-type MOs play the most significant role in the N peaks of such ferrous-CO complexes. Here, the b2u-type MOs have a large contribution from the imidazole π orbital.

Ultrasound-assisted extraction of tamarind xyloglucan: an effective approach to reduce the viscosity and improve the α-amylase inhibition of xyloglucan.

BACKGROUND: Water extraction (WE) is the classical extraction method for tamarind xyloglucan (XyG), but its low yield, high viscosity and poor dispersion in aqueous solution are not conducive to the industrial applications. To promote the industrial application of tamarind XyG, an ultrasonic-assisted extraction (UAE) method for extracting low-viscosity XyG from tamarind kernel powder was proposed. RESULTS: The yield of UAE-XyG was higher (502.33 ± 0.036 g kg-1 ) than that of WE-XyG (163.43 ± 0.085 g kg-1 ). UAE reduced the molecular weight, monosaccharide content and apparent viscosity of XyG. The hypoglycemic experiment in vitro showed that UAE-XyG had a stronger inhibitory effect on α-amylase activity than WE-XyG, but its glucose dialysis retardation index was lower. CONCLUSION: In sum, UAE is a type of extraction method that could effectively improve the yield of XyG and reduce its viscosity to expand its application without reducing its physiological activity. UAE exhibits an excellent potential in the extraction of XyG. © 2022 Society of Chemical Industry.

A π-extended benzothiadiazole derivative for a high-efficiency TADF-sensitized fluorescent organic light-emitting diode.

A new fluorescent emitter based on π-extended benzothiadiazole was synthesized. The emitter exhibited a large molar extinction coefficient, a high quantum yield of 98% and a large radiative decay rate of 108 s-1. Moreover, the obtained TADF-sensitized fluorescent OLED displayed excellent device performance with a high EQEmax of 14.3%.

The Bonding Nature of Fe-CO Complexes in Heme Proteins.

Although carbon monoxide (CO) has been known to bind to the ferrous heme in cytochrome P450 enzymes (P450s) since the earliest days of P450 research, details on the nature of the ferrous-CO bonding remain elusive. This study employed dispersion-corrected density functional theory (DFT) calculations and DFT-based theoretical analyses to investigate the complexes between CO and a thiolate- or imidazole-ligated heme that contains ferric or ferrous iron. Traditionally, the ferrous-CO bonding in heme systems has been interpreted qualitatively in terms of σ donation and π backdonation. Complementary occupied-virtual orbital pair (COVP) analysis yielded one orbital pair for σ donation and two for π backdonation together with the specific magnitude of their energetic contributions. The charge-transfer effect for these three orbital pairs has nearly the same energetic significance in the ferrous-CO complexes. Therefore, in total, the π-backdonation effect is much greater than the σ-donation effect. In contrast, the σ-donation effect is more significant in the ferric-CO complex because of the less efficient π backdonation. The nature of ferric-CO and ferrous-CO bonding was further scrutinized using the generalized Kohn-Sham energy decomposition analysis (GKS-EDA) scheme, whose results highlighted the significance of various effects in enhancing the Fe-CO bonding for the thiolate- and imidazole-ligated heme groups. In particular, the intrinsic repulsion effect plays a crucial role in promoting the preferential binding of CO toward the ferrous heme and in determining the geometry of the complexes.

Occupational benefit perception of acute and critical care nurses: A qualitative meta-synthesis.

Background: With the development of society, nurses have an increasingly more important role in the medical team. At the same time, due to various reasons, the number of active nurses is continuously decreasing, and the shortage of nursing personnel is becoming ever more serious. The COVID-19 pandemic made these clinical problems more serious. As the department with the greatest work pressure and the most intense pace, acute and critical care nurses are already facing serious problems related to job burnout and dismission. In the context of the COVID-19 pandemic, these problems should be solved urgently. Furthermore, with the rise of positive psychology, many scholars are turning their research direction to the positive professional experience of nurses so as to get inspiration to encourage nurses to face work with an optimistic attitude and guide nursing managers to better retain nursing talents. Objective: The purpose of this paper is to summarize and evaluate the positive emotional experience and professional benefit of acute and critical care specialist nurses in the process of work. So as to better interpret their occupational benefit perception and guide nursing managers in adopting positive measures and promoting the development of high-quality nursing. Methods: Cinahl plus, Embase, Medline and other twelve databases were searched for relevant literature. Meta-aggregation was used to synthesize the findings of the included studies. Results: From a total of 12 articles included in this study, 55 main results were presented, 8 new categories were integrated, and three themes were formed: professional identity, social support, and personal growth. The professional identity included: being proud of professional ability and increasing professional value; social support included: friends and family support, organizational, environmental support, peer support, and support of patients and their families; personal growth included realizing self-worth and promoting self-development. Conclusion: Hospital managers should pay attention to the positive emotional experience of nurses in work and based on this, provide practical and beneficial protection for nurses from the aspects of salary, learning opportunities, working environment, social support and internal personality, stimulate work enthusiasm, guide nurses to correctly face negative emotions and occupational pressure, and improve the sense of professional benefit.

Energy Decomposition Analysis of the Nature of Coordination Bonding at the Heme Iron Center in Cytochrome P450 Inhibition.

Drug compounds or their metabolic intermediates (MIs) sometimes inhibit the function of cytochrome P450 enzymes (P450s) by forming a coordination bond with the Fe(III) heme or Fe(II) heme of P450s. Such inhibition is one of the major causes of drug-drug interactions (DDIs), a subject of longstanding academic and practical interest. However, such coordination bonding is not fully understood at the quantum mechanical level, thus hampering rational improvement of the accuracy of DDI-related predictions. In this work, we employed density functional theory (DFT) and the generalized Kohn-Sham energy decomposition analysis (GKS-EDA) scheme to investigate the nature of the coordination bonding formed in the reversible and quasi-irreversible inhibition of P450s. The GKS-EDA results highlighted a previously unrecognized role of the electron correlation effect in P450 inhibition. The correlation effect tends to be larger in Fe(II) complexes of MI-type inhibitors and is particularly prominent for the nitrosoalkane ligand. An additional natural bond orbital (NBO) analysis provided insight into the relative significance of the σ donation and π backdonation effects in various heme-inhibitor complexes.

Indole metabolism mechanisms in a new, efficient indole-degrading facultative anaerobe isolate Enterococcus hirae GDIAS-5.

Indole is an inter-species and inter-kingdom signaling molecule widespread in the natural world. A large amount of indole in livestock wastes makes it difficult to be degraded, which causes serious malodor. Identifying efficient and eco-friendly ways to eliminate it is an urgent task for the sustainable development of husbandry. While bioconversion is a widely accepted means, the mechanism of indole microbial degradation is little understood, especially under anaerobic conditions. Herein, a new Enterococcus hirae isolate GDIAS-5, effectively degraded 100 mg/L indole within 28 h aerobically or 5 days anaerobically. Three intermediates (oxindole, isatin, and catechol) were identified in indole degradation, and catechol was further degraded by a meta-cleavage catabolic pathway. Two important processes for GDIAS-5 indole utilization were discovered. One is Fe(III) uptake and reduction, which may be a critical process that is coupled with indole oxidation, and the other is the entire pathway directly involved in indole oxidation and metabolism. Furthermore, monooxygenase ycnE responsible for indole oxidation via the indole-oxindole-isatin pathway was identified for the first time. Bioinformatic analyses showed that ycnE from E. hirae formed a phylogenetically separate branch from monooxygenases of other species. These findings provide new targets and strategies for synthetic biological reconstruction of indole-degrading bacteria.

Iron-Catalyzed Photoredox Functionalization of Methane and Heavier Gaseous Alkanes: Scope, Kinetics, and Computational Studies.

Herein, we report the development of the photocatalytic C-H functionalization of methane, ethane, and heavier gaseous alkanes with good yields and selectivity, broad scope (57 examples), mild conditions, and low cost. Kinetics and density functional theory calculations were investigated for the key photoinduced ligand-to-metal charge transfer and hydrogen atom transfer processes to reveal the detailed mechanism of iron photocatalysis. This work may bring novel ideas for feedstock upgrading and catalyst design.

Doubly-Reduced Pentacene in Different Coordination Environments: X-ray Crystallographic and Theoretical Insights into Structural and Electronic Changes.

Chemical reduction of pentacene (C22 H14 , 1) with Group 1 metals ranging from Li to Cs revealed that 1 readily undergoes a two-fold reduction to afford a doubly-reduced 12- anion in THF. With the help of 18-crown-6 ether used as a secondary coordinating agent, five π-complexes of 12- with different alkali metal counterions have been isolated and fully characterized. This series of complexes enables the first evaluation of alkali-metal ion binding patterns and structural changes of the 12- dianion based on the crystallographically confirmed examples. The difference in coordination of the smallest Li+ ion vs. heavier Group 1 congeners has been demonstrated. In addition, the use of benzo-15-crown-5 in the reaction of 1 with Na metal allowed the isolation of the unique solvent-separated ion product with a "naked" dianion, 12- . The detailed structural analyses of the series revealed the C-C bond alteration and core deformation of pentacene upon two-fold reduction and complexation. The negative charge localization at the central six-membered ring of 12- identified by theoretical calculations corroborates with the X-ray crystallographic results. Subsequent in-depth theoretical analysis provided a detailed description of changes in the electronic structure and aromaticity of pentacene upon reduction.

Similar infection rates in a new wound closure method following knee arthroplasty.

Surgical site infections, defined as acute wound infections requiring surgical intervention within 90 days post-surgery, were retrospectively compared between a novel, zipper-like closure method (ZM) and staples in 682 patients (904 knees) and 772 patients (971 knees), respectively. The incidence of deep infections was 0.6% for staples and 0.2% for ZM (p = 0.169) and superficial infections was 0.1% for staples and 0.0% for ZM (p = 0.518). With no difference in wound complications, the ZM may be preferred since the two-week post-operative clinic visit required for wound check and staple removal was eliminated, thereby, decreasing clinic volume.