Umpolung-Enabled Divergent Dearomative Carbonylations.

Although dearomative functionalizations enable the direct conversion of flat aromatics into precious three-dimensional architectures, the case for simple arenes remains largely underdeveloped owing to the high aromatic stabilization energy. We herein report a dearomative sequential addition of two nucleophiles to arene π-bonds through umpolung of chromium-arene complexes. This mode enables divergent dearomative carbonylation reactions of benzene derivatives by tolerating various nucleophiles in combination with alcohols or amines under CO-gas-free conditions, thus providing modular access to functionalized esters or amides. The tunable synthesis of 1,3- or 1,4-cyclohexadienes as well as the construction of carbon quaternary centers further highlight the versatility of this dearomatization. Diverse late-stage modifications and derivatizations towards synthetically challenging and bioactive molecules reveal the synthetic utility. A possible mechanism was proposed based on control experiments and intermediate tracking.

Promoted iron corrosion and subsequent hexavalent chromium removal in zero-valent iron systems by oxidant activation.

Zero-valent iron (ZVI), as an effective medium, is widely used to eliminate heavy metal ions in filter tanks. However, it will react with Cr(VI) to generate Fe-Cr precipitates with low conductivity on its surface, resulting in slow iron corrosion and low Cr(VI) removal efficiency. In this study, three oxidants (KMnO4, NaClO, and Na2S2O8) were employed to promote iron corrosion in ZVI systems for enhanced Cr(VI) removal at a concentration of 5 mg/L through batch tests and column experiments. The ZVI/KMnO4, ZVI/NaClO, and ZVI/Na2S2O8 systems achieved significantly higher Cr(VI) removal rates of 31.5%, 52.8%, and 65.9% than the ZVI system (9.8%). Solid phase characterization confirmed that these improvements were attributed to promoted iron corrosion and secondary mineral formation (e.g., lepidocrocite, ferrihydrite, and magnetite) by oxidants. Those minerals offered more reaction sites for Cr(VI) reduction, adsorption, and sequestration. Cycle experiments indicated that ZVI/oxidant systems could stably remove Cr(VI). In long-term column experiment, the ZVI/NaClO column showed a much longer life-span and exhibited a 34.8 times higher Cr(VI) removal capacity than that of the ZVI column. These findings demonstrated that ZVI in combination with a reasonable amount of oxidants was a promising method for removing Cr(VI) in practical filter tanks and provided a new insight to enhance Cr(VI) removal.

The roles of stress mindset and personality in the impact of life stress on emotional well-being in the context of Covid-19 confinement: A diary study.

Previous studies indicate that COVID-19 confinement has led to an increase in psychological distress and a decrease in overall well-being. This longitudinal study aims to investigate how stress mindset and personality traits moderate the impact of life stress on the development of emotional well-being during the COVID-19 pandemic confinement. Our study collected daily life stress and emotions data from 134 participants over 14 consecutive days using the diary method. We used hierarchical linear modeling (HLM) to analyze the data, examining within-person and between-person effects. Life stress predicted moderate increases in positive emotions and strong increases in negative emotions over time. A stress-is-enhancing stress mindset was associated with greater positive emotions at baseline and mitigated the link between life stress and negative emotions. Among the Big Five personality traits, extraversion, openness, agreeableness, and conscientiousness were associated with higher baseline levels of positive emotions. Agreeableness and conscientiousness mitigated the link between life stress and negative emotions. Neuroticism was associated with higher baseline levels of negative emotions and moderately mitigated the link between life stress and positive emotions. The interaction between neuroticism and stress-is-enhancing mindset predicted greater negative emotions and mitigated the link between life stress and positive emotions. In contrast, the interaction between stress-is-enhancing mindset and the other four personality traits mitigated the positive link between life stress and negative emotions. Overall, these findings suggest that life stress from confinement leads to a decrease in daily emotional well-being as the confinement prolongs. Personality traits-agreeableness, conscientiousness, and a stress-is-enhancing stress mindset-act as protective roles in mitigating life stress' effect on reduced emotional well-being over time. The findings advance our knowledge in understanding the roles of personality traits and stress-is-enhancing mindset in explaining the heterogeneity in the impact of life stress on emotional well-being.

AI-assisted compressed sensing and parallel imaging sequences for MRI of patients with nasopharyngeal carcinoma: comparison of their capabilities in terms of examination time and image quality.

OBJECTIVE: To compare examination time and image quality between artificial intelligence (AI)-assisted compressed sensing (ACS) technique and parallel imaging (PI) technique in MRI of patients with nasopharyngeal carcinoma (NPC). METHODS: Sixty-six patients with pathologically confirmed NPC underwent nasopharynx and neck examination using a 3.0-T MRI system. Transverse T2-weighted fast spin-echo (FSE) sequence, transverse T1-weighted FSE sequence, post-contrast transverse T1-weighted FSE sequence, and post-contrast coronal T1-weighted FSE were obtained by both ACS and PI techniques, respectively. The signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and duration of scanning of both sets of images analyzed by ACS and PI techniques were compared. The images from the ACS and PI techniques were scored for lesion detection, margin sharpness of lesions, artifacts, and overall image quality using the 5-point Likert scale. RESULTS: The examination time with ACS technique was significantly shorter than that with PI technique (p < 0.0001). The comparison of SNR and CNR showed that ACS technique was significantly superior with PI technique (p < 0.005). Qualitative image analysis showed that the scores of lesion detection, margin sharpness of lesions, artifacts, and overall image quality were higher in the ACS sequences than those in the PI sequences (p < 0.0001). Inter-observer agreement was evaluated for all qualitative indicators for each method, in which the results showed satisfactory-to-excellent agreement (p < 0.0001). CONCLUSION: Compared with the PI technique, the ACS technique for MR examination of NPC can not only shorten scanning time but also improve image quality. CLINICAL RELEVANCE STATEMENT: The artificial intelligence (AI)-assisted compressed sensing (ACS) technique shortens examination time for patients with nasopharyngeal carcinoma, while improving the image quality and examination success rate, which will benefit more patients. KEY POINTS: • Compared with the parallel imaging (PI) technique, the artificial intelligence (AI)-assisted compressed sensing (ACS) technique not only reduced examination time, but also improved image quality. • Artificial intelligence (AI)-assisted compressed sensing (ACS) pulls the state-of-the-art deep learning technique into the reconstruction procedure and helps find an optimal balance of imaging speed and image quality.

Intermolecular Dearomative 1,2-Amination/Carbonylation via Nucleophilic Addition of Simple Amines to Arene π-Bonds.

The incorporation of the privileged amino functionality is of paramount importance in organic synthesis. In contrast to the well-developed amination methods for alkenes, the dearomative amination of arenes is largely underexplored due to the inherently inert reactivity of arene π-bonds and selectivity challenges. Herein, we report an intermolecular dearomative aminofunctionalization via direct nucleophilic addition of simple amines to chromium-bound arenes. This multicomponent 1,2-amination/carbonylation reaction enables rapid access to complicated alicyclic compounds containing amino and amide functionalities from benzene derivatives under CO-gas-free conditions, which also represents the first application of nitrogen-based nucleophiles in η6 -coordination-induced arene dearomatizations.

Group citizenship behaviour in healthcare organization, doctor-patient relationship, work engagement and turnover intention: A moderated mediation model.

The effective functioning of health care organisations depends on the inter-professional collaboration among healthcare professionals from diverse backgrounds, representing different work units, to provide quality services. This study aims to understand how group citizenship behaviour (GCB) that supports other work groups may moderate the relationship between doctor-patient relationship (DPR), Work Engagement (WE) and Turnover Intention (TI). The data for this study were collected through two waves of questionnaire survey at a tertiary public hospital in China. The hypothesised model was tested by Hayes' PROCESS macro. There were significant differences of perceived GCB across different professional units with work units practicing a multidisciplinary working approach and working in the high-stake working environment reported higher levels of GCB. The results show that WE mediates the relationships between DPR and TI and GCB accentuates the positive relationship between DPR and WE. Specifically, the path between DPR and WE was stronger for individuals with high perceived GCB than those with low perceived GCB. The study contributes to the development of Job Demands-Resources model with integrating GCB into the model and enriching the challenge job demand conceptualisation by focussing on DPR in Chinese health care setting. In practice, the hospital administrators should encourage GCB to improve organizational effectiveness and doctors' attitudes.

Chemoselective 1,2-Reduction and Regiodivergent Deuteration of Chromium-Bound Arenes.

Herein, a general strategy for chemo- and regioselective 1,2-reduction of chromium-bound arenes was developed, thus providing rapid access to 1,3-cyclohexadienes. Selective arene activation via π-complexation along with the use of mild hydride Ph3 SiH can overcome the inherently low reactivity of arene π-bonds while tolerating various reduction-sensitive functional groups. Its versatility further enables a regiodivergent deuteration. Using different sequences of (non)deuterated hydride and acid reagents, the deuterated positions as well as the degrees of deuterium incorporation can be controlled precisely, which leads to a large and previously inaccessible chemical space for 1,3-cyclohexadiene isotopologues. A reasonable mechanism was proposed based on intermediate capture and control experiments. The synthetic value of this selective 1,2-reduction was demonstrated in the formal total synthesis of (±)-galanthamine and (±)-lycoramine.

Quantitative synthetic MRI for predicting locally advanced rectal cancer response to neoadjuvant chemoradiotherapy.

OBJECTIVES: To investigate the value of pre-treatment quantitative synthetic MRI (SyMRI) for predicting a good response to neoadjuvant chemoradiotherapy (nCRT) in patients with locally advanced rectal cancer. METHODS: This prospective study enrolled 63 patients with locally advanced rectal cancer scheduled to undergo preoperative chemoradiotherapy from January 2019 to June 2021. T1 relaxation time (T1), T2 relaxation time (T2), proton density (PD) from synthetic MRI, and apparent diffusion coefficient (ADC) from diffusion-weighted imaging (DWI) were measured. Independent-sample t-test, the Mann-Whitney U test, the Delong test, and receiver operating characteristic curve (ROC) analyses were used to predict the pathologic complete response (pCR) and T-downstaging. RESULTS: Among the 63 patients, 19 (30%) achieved pCR and 44 (70%) did not, and 24 (38%) achieved T-downstaging, while 44 (62%) did not. The mean T1 and T2 values were significantly lower in the pCR group compared with those in the non-pCR group and in the T-downstage group compared with those in the non-T-downstage group (all p < 0.05). There were no significant differences in the PD and ADC values between the two groups. There were no significant differences between the mean values of T1 and T2 for predicting pCR after CRT (AUC, 0.767 vs. 0.831, p = 0.37). There were no significant differences between the AUC values of T1 and T2 values for the assessment of post-CRT T-downstaging (AUC, 0.746 vs. 0.820, p = 0.506). CONCLUSIONS: In patients with locally advanced rectal cancer, the synthetic MRI-derived T1 relaxation time and T2 relaxation time values are promising imaging markers for predicting a good response to neoadjuvant chemoradiotherapy. KEY POINTS: • Mean T1 and T2 values were significantly lower in the pathologic complete response group and the T-downstage group. • There were no significant differences in the proton density and apparent diffusion coefficient values between the two groups.

Dearomative Aminocarbonylation of Arenes via Bifunctional Coordination to Chromium.

Amides are ubiquitous in physical and life sciences. Given the significant abundance of arenes, dearomative aminocarbonylation of arenes would lead to a large and underexplored chemical space for amide discovery. However, such reactions are challenging due to the high degree of resonance stabilization and selectivity issues. Herein, we disclose an unprecedented dearomative trifluoromethylative aminocarbonylation of arenes via bifunctional coordination to chromium, providing a modular platform for the construction of amides possessing trifluoromethyl (CF3 ) groups and three-dimensional rings. Its versatility further enabled a switchable difluoromethylation or trifluoromethylation aminocarbonylation of arene C-H bonds. A possible mechanism was proposed based on control experiments. Finally, the synthetic utility was well demonstrated by diverse applications in the total synthesis of CF3 -functionalized amide-type drugs, including praziquantel, nateglinide, maraviroc and alloyohimbane.

Diagnostic performance of synthetic magnetic resonance imaging in the prognostic evaluation of rectal cancer.

Background: Numerous factors are related to the prognosis of rectal cancer, including T stage, N stage, metastasis, extramural venous invasion (EMVI), circumferential resection margin (CRM), and tumor differentiation. However, it is still a challenge to precisely evaluate them before therapy; therefore, we investigate whether synthetic magnetic resonance imaging and apparent diffusion coefficient (ADC) values could help predict the prognostic factors of rectal cancer. Methods: Eighty-seven patients (55 men and 32 women; mean age, 59±11 years) with pathologically confirmed rectal cancer were enrolled. Preoperative quantitative metrics, including T1, T2, proton density (PD), and ADC values, were measured with diffusion-weighted imaging (DWI) acquired by a single-shot echo-planar sequence and synthetic magnetic resonance imaging acquired by a multi-dynamic multi-echo sequence at 3.0 T, in patients with rectal cancer by two radiologists. We evaluated the diagnostic performance of synthetic magnetic resonance imaging using the independent sample t-test or Mann-Whitney U test and receiver operating characteristic (ROC) curve and multivariate logistic regression analyses and compared the area under the ROC curve of quantitative values using the DeLong test. Results: The T2 and PD values showed a significant reduction among patients with poor differentiation and lymph node metastasis in rectal cancer. The area under the ROC curve values of T2 and PD values for predicting magnetic resonance imaging N stage and differentiation were 0.734, 0.682, and 0.673, 0.686, respectively. Moreover, combining T2 and PD values for magnetic resonance imaging N stage slightly improved the area under the ROC curve value of 0.774 (95% CI, 0.673-0.876). In the present study, the ADC and T1 values were not significant in the differentiation or clinical stage of rectal cancer (RC). Conclusions: Quantitative T2 and PD values obtained by synthetic magnetic resonance imaging might be used for evaluating prognostic factors of rectal cancer noninvasively. Furthermore, combining T2 and PD values further improved the diagnostic performance of magnetic resonance imaging N staging in rectal cancer. The ADC and T1 values were not significant in the differentiation or clinical stage of RC.

A facile modification of cation exchange resin by nano-sized goethite for enhanced Cr(VI) removal from water.

A novel macroporous strong acidic cation exchange resin (D001) modified by nano-sized goethite (nFeOOH@D001) was fabricated by using a facile ethanol dispersion and impregnation method, and its efficiency for Cr(VI) removal was tested thereafter. Due to the dispersing effect of ethanol, FeOOH particles of 20-150 nm were coated on the D001 surfaces. The nFeOOH@D001 obtained a Cr(VI) removal efficiency and capacity of 80.2% and 7.4 mg/g respectively, 5 times and 8 times higher than that of the pristine D001. The Cr(VI) removal by nFeOOH@D001 followed the pseudo second-order kinetics and the Langmuir adsorption model. Column experiments also demonstrated that the nFeOOH@D001 exhibited a much better ability to remove Cr(VI) as compared to the D001. Additionally, the nFeOOH@D001 showed a potential for reusability and renewability. The adsorbed nFeOOH@D001 could be easily desorbed by 0.1 M acetic acid and a reuse efficiency of 92.7% could be maintained after 4 desorption-adsorption cycles. The used nFeOOH@D001 could be eluted by 0.1 M HCl to remove nFeOOH, and the renewed D001 could be recoated by nFeOOH and achieved a regeneration rate of 97.8% for Cr(VI) removal. The above results indicated that nano-sized goethite modification is a promising method to endow D001 with the ability to remove Cr(VI) from water.

Exploring the doctor-patient relationship as a challenge job demand: application of the job demands-resources model in a Chinese public hospital.

In the increasingly commercialized healthcare environment in China, doctor-patient relationship (DPR) is a job demand for doctors that is linked to various motivational outcomes. Drawing on the Job Demands-Resources (JD-R) model, and the conservation of resources theory, we develop a preliminary conceptual model that links Leader Member Exchange (LMX) as a job resource, and DPR as a challenge job demand, to the levels of work engagement and turnover intentions of doctors working in this healthcare environment. Using two-wave data collected from 381 doctors in a public hospital, we found support for the hypothesized model. Results of a series of SEM analyses revealed that LMX was positively related to DPR and work engagement, while DPR partially mediates the path from LMX to work engagement. In addition, LMX is negatively related to turnover intentions through DPR and subsequently work engagement. Theoretically, this study contributes to the development of the JD-R model by investigating the concept of challenge job demand, and its role in the motivational process, with new evidence from healthcare occupations in China. Practically, this study contributes to the limited number of studies on managing the changing nature of the DPR in China, and in seeking potential solutions based on established organizational constructs.

Emotional well-being in COVID-19 mass quarantine: the role of personal response and life activity: a 14-day diary study in China.

OBJECTIVES: This study aims to explore quarantined individuals' emotional well-being over time and how personal response and life activity predict emotional well-being and its change. DESIGN/METHODS: Daily data were collected from 134 participants with 71 having 14 consecutive days' data. Hierarchical linear modeling (HLM) and General Linear Model (GLM) were used to examine the primary tests. RESULTS: Overall, positive and negative emotions declined significantly during the surveyed period. Meanwhile, differences were observed in the level of positive, depressed, and negative emotions and/or patterns of change among different population categories. The personal response of worrying about work and life was positively related to depressed and negative emotions at baseline, but was negatively related to the development of both depressed and negative emotions over time. Among life activities, family stressor was a significant predictor for both depressed and negative emotions while social support predicted positive emotions. Moreover, health & hygiene activity was positively related to positive emotions at baseline. CONCLUSIONS: The results provide scientific evidence for public health policymakers on quarantine policies and inform the general public about quarantine life. They highlight the importance of addressing the needs of vulnerable groups (parents with young children, divorcees, clinicians) during the pandemic, and demonstrate the benefits of promoting healthcare and hygiene activity, having a sense of worry and access to social support.

Enhanced phosphate removal by zero valent iron activated through oxidants from water: batch and breakthrough experiments.

In this study, oxidants including hydrogen peroxide (H2O2), hypochlorite (ClO-) and persulfate (S2O8 2-) were employed to promote zero-valent iron (ZVI) corrosion and enhance phosphate (P) removal from water through batch and breakthrough experiments. Characterization results indicated that the addition of oxidant can cause large-scale corrosion of the iron surface. This subsequently generates more iron ions and active minerals, resulting in a large number of reaction-adsorption sites for P removal. Therefore, compared with the ZVI alone system (29.4%), the removal efficiency of P by oxidant/ZVI system (H2O2 : ClO- : S2O8 2- = 33.2% : 54% : 67.1%) was improved. For the oxidant/ZVI system, H2O2 can promote the corrosion of ZVI to a certain extent. However, the solution pH could be increased during the corrosion process. This leads to inhibition of P removal performance by the H2O2/ZVI system, which only increased by 12.9% to 33.2%. The reaction between NaClO and ZVI consumes less H+, and the reaction product Cl- can pierce the passivation layer on the surface of the ZVI through the pitting effect. As such, the NaClO/ZVI system attained a 54% P removal rate. Compared with H2O2 and NaClO, a better P removal effect of about 67.1% can be achieved by using Na2S2O8, since the oxidation corrosion process of Na2S2O8 does not consume H+, and it also has the strongest oxidizing properties. Furthermore, an appropriate increase in oxidant dosing (0.1-2 mM) could improve the efficiency at which of P is removed. Five batch cycle experiments showed that the oxidant/ZVI system has a higher removal capacity and longer life-span. In the long-term column running, the P removal capacity and operation life of the NaClO/ZVI column are 9.6 times and 3.2 times higher than that of the ZVI column, respectively. This work demonstrates that an oxidant/ZVI system can be an efficient method for P removal in water, which also provides a new idea for solving the problem of ZVI corrosion passivation.

A non-lab nomogram of survival prediction in home hospice care patients with gastrointestinal cancer.

BACKGROUND: Patients suffering from gastrointestinal cancer comprise a large group receiving home hospice care in China, however, little is known about the prediction of their survival time. This study aimed to develop a gastrointestinal cancer-specific non-lab nomogram predicting survival time in home-based hospice. METHODS: We retrospectively studied the patients with gastrointestinal cancer from a home-based hospice between 2008 and 2018. General baseline characteristics, disease-related characteristics, and related assessment scale scores were collected from the case records. The data were randomly split into a training set (75%) for developing a predictive nomogram and a testing set (25%) for validation. A non-lab nomogram predicting the 30-day and 60-day survival probability was created using the least absolute shrinkage and selection operator (LASSO) Cox regression. We evaluated the performance of our predictive model by means of the area under receiver operating characteristic curve (AUC) and calibration curve. RESULTS: A total of 1618 patients were included and divided into two sets: 1214 patients (110 censored) as training dataset and 404 patients (33 censored) as testing dataset. The median survival time for overall included patients was 35 days (IQR, 17-66). The 5 most significant prognostic variables were identified to construct the nomogram among all 28 initial variables, including Karnofsky Performance Status (KPS), abdominal distention, edema, quality of life (QOL), and duration of pain. In training dataset validation, the AUC at 30 days and 60 days were 0.723 (95% CI, 0.694-0.753) and 0.733 (95% CI, 0.702-0.763), respectively. Similarly, the AUC value was 0.724 (0.673-0.774) at 30 days and 0.725 (0.672-0.778) at 60 days in the testing dataset validation. Further, the calibration curves revealed good agreement between the nomogram predictions and actual observations in both the training and testing dataset. CONCLUSION: This non-lab nomogram may be a useful clinical tool. It needs prospective multicenter validation as well as testing with Chinese clinicians in charge of hospice patients with gastrointestinal cancer to assess acceptability and usability.