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Biodegradation of hydrophobic volatile organic compounds (VOCs) such as n-hexane is limited by their poor accessibility. Constructing fungal-bacterial degradation alliances is an effective approach, but the role of those fungi without the capability to degrade VOCs may have been overlooked. In this study, a non-n-hexane-degrading fungus, Fusarium keratoplasticum FK, was utilized to enhance n-hexane degradation by the bacterium Mycobacterium neworleansense WCJ. It was shown that strain WCJ removed 64.84% of n-hexane (at a concentration of 648.20 mg L-1) over 3 d, and 84.04% after introducing strain FK. Microbial growth kinetic studies revealed that the growth of strain WCJ was also promoted. Through a stepwise adsorption-degradation experiment combined with qPCR technology, it was found that the strain WCJ could utilize the n-hexane pre-adsorbed by strain FK, with an increase in copy number from 108.2662 to 108.7731. Therefore, the non-degrading fungi can improved the accessibility of n-hexane by providing n-hexane adsorbed by the mycelium to the degrading bacteria. In addition, the adsorption tests and characterization of the fungal samples before and after Soxhlet extraction indicated that the adsorption of n-hexane on strain FK conformed to Lagergren's pseudo-second-order kinetics and Freundlich adsorption isotherms, and was correlated with the presence of lipids and nonpolar groups. This study emphasizes the potential role of non-degrading fungi in bioremediation and proposes a viable strategy to enhance the bacterial degradation of hydrophobic VOCs.
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Conventional food production is restricted by energy conversion efficiency of natural photosynthesis and demand for natural resources. Solar-driven artificial food synthesis from CO2 provides an intriguing approach to overcome the limitations of natural photosynthesis while promoting carbon-neutral economy, however, it remains very challenging. Here, we report the design of a hybrid electrocatalytic-biocatalytic flow system, coupling photovoltaics-powered electrocatalysis (CO2 to formate) with five-enzyme cascade platform (formate to sugar) engineered via genetic mutation and bioinformatics, which achieves conversion of CO2 to C6 sugar (L-sorbose) with a solar-to-food energy conversion efficiency of 3.5%, outperforming natural photosynthesis by over three-fold. This flow system can in principle be programmed by coupling with diverse enzymes toward production of multifarious food from CO2. This work opens a promising avenue for artificial food synthesis from CO2 under confined environments.
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Herein, a practical and effective synthesis of thioesters from readily available carboxylic acids and odorless disulfides was developed under photocatalytic conditions. This approach involves phosphoranyl radical-mediated fragmentation to generate acyl radicals and allows for incorporation of both S atoms of the disulfides into the desired products. In addition to batch reactions, a continuous-flow reactor was employed, enabling rapid thioester synthesis on a gram scale. Preliminary experimental mechanistic studies and the rapid synthesis of dalcetrapib are also demonstrated.
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Programmable artificial photosynthetic cell is the ultimate goal for mimicking natural photosynthesis, offering tunable product selectivity via reductase selection toward device integration. However, this concept is limited by the capacity of regenerating the multiple cofactors that hold the key to various reductases. Here, we report the design of artificial photosynthetic cells using biotic-abiotic thylakoid-CdTe as hybrid energy modules. The rational integration of thylakoid with CdTe quantum dots substantially enhances the regeneration of bioactive NADPH, NADH and ATP cofactors without external supplements by promoting proton-coupled electron transfer. Particularly, this approach turns thylakoid highly active for NADH regeneration, providing a more versatile platform for programming artificial photosynthetic cells. Such artificial photosynthetic cells can be programmed by coupling with diverse reductases, such as formate dehydrogenase and remodeled nitrogenase for highly selective production of formate or methane, respectively. This work opens an avenue for customizing artificial photosynthetic cells toward multifarious demands for CO2 conversion.
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Compostos de Cádmio , Pontos Quânticos , Dióxido de Carbono , NAD , Telúrio , Fotossíntese , NitrogenaseRESUMO
Background: Emerging evidence has been reported of attentional dysfunction in pituitary adenoma patients. However, the effect of pituitary adenomas on lateralized attention network efficiency remained to be clear. Thus, the present study aimed to investigate the impairment of lateralized attention networks in patients with pituitary adenoma. Methods: Eighteen pituitary adenoma patients (PA group) and 20 healthy controls (HCs) were included in this study. Both behavioral results and event-related potentials (ERPs) were acquired while subjects performed the Lateralized Attention Network Test (LANT). Results: Behavioral performances indicated the PA group had a slower reaction time and a similar error rate relative to the HCs group. Meanwhile, significantly increased executive control network efficiency suggested the dysfunction of inhibition control in PA patients. Regarding ERP results, there were no group differences in the alerting and orienting networks. The target-related P3 was significantly reduced in the PA group, suggesting an impairment of executive control function and attentional resources allocation. Moreover, the mean amplitude of P3 was significantly lateralized to the right hemisphere, and interacted with the visual field, exhibiting that the right hemisphere dominated the bilateral visual field, whereas the left hemisphere dominated the left visual field. In the specific high-conflict condition, the pattern of hemispheric asymmetry in the PA group was altered due to a mixed effect resulting from the compensatory recruitment of attentional resources in the left central parietal area and the destructive effects of hyperprolactinemia. Conclusion: These findings suggested that, in the lateralized condition, the decreased P3 in the right central parietal area and the diminished hemispheric asymmetry under high conflict load, may serve as the potential biomarkers of attentional dysfunction in patients with pituitary adenoma.
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Oxidative carbonylation of methane is an appealing approach to the synthesis of acetic acid but is limited by the demand for additional reagents. Here, we report a direct synthesis of CH3COOH solely from CH4 via photochemical conversion without additional reagents. This is made possible through the construction of the PdO/Pd-WO3 heterointerface nanocomposite containing active sites for CH4 activation and C-C coupling. In situ characterizations reveal that CH4 is dissociated into methyl groups on Pd sites while oxygen from PdO is the responsible for carbonyl formation. The cascade reaction between the methyl and carbonyl groups generates an acetyl precursor which is subsequently converted to CH3COOH. Remarkably, a production rate of 1.5 mmol gPd-1 h-1 and selectivity of 91.6% toward CH3COOH is achieved in a photochemical flow reactor. This work provides insights into intermediate control via material design, and opens an avenue to conversion of CH4 to oxygenates.
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Although it has been long recognized that leader-member exchange social comparison (LMXSC) has critical implications for employee productivity, little attention has been given to systematically exploring the effects of LMXSC on employee performance in a specific cultural context. Integrating social exchange theory with social comparison theory, we examine a dual process model to explain how and when LMXSC affects employee performance outcomes in the Chinese context. Results based on multiphase, multisource data from China revealed that the mediating roles of employees' perceived obligation toward the leader and self-esteem are examined simultaneously in the relationship between LMXSC and job performance and organizational citizenship behavior (OCB). Additionally, guanxi strengthens the connection between LMXSC and perceived obligation, while Zhongyong thinking erodes the connection between LMXSC and self-esteem. Taken together, these findings enhance our understanding of LMXSC in China.
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Prolactinomas have been reported to impair cognition in broad aspects. However, few studies investigated the influence of prolactinomas on cognitive flexibility never mentioning the underlying neural and electrophysiological mechanism. We recorded scalp electroencephalography (EEG) in a colour-shape switching task. Patients with prolactinomas showed longer reaction time in switch trials and larger switch costs relative to healthy controls (HCs). Compared to HCs who showed stronger frontal theta activity in switch trials, the generally weak frontal theta activity in patients implied that they could not afford the executive control to configure task sets. Meanwhile, machine-learning based classification revealed that patients manifested non-selective brain patterns in response to different task types (colour vs. shape task) and different task states (switch vs. repeat state), which collectively suggested the cognitive dysfunction in preparation for a changing environment. Compared to HCs who showed stronger frontoparietal synchronization in switch trials, this enhanced frontoparietal connectivity was disrupted among patients with severe prolactinomas. This finding implicated greater hyperprolactinemia was linked to a larger decrease in cognitive performance. Taken together, the present study highlighted frontal theta power, and frontoparietal connectivity at theta band as the electrophysiological markers of the impaired cognitive flexibility and task control in patients with prolactinomas.
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BACKGROUND: The miserable work conditions faced by many nurses around the world make them particularly prone to work-family conflict. PURPOSE: This study was designed to explain from a resource perspective how and when nurses experiencing work-family conflict are more likely to exhibit decreased levels of organizational identification and professional identification. METHODS: A time-separation research design was used, and data were collected from 322 nurses in five hospitals in China. All of the hypotheses were tested using conduct structural equation modeling. RESULTS: The results showed that work-family conflict had negative effects on organizational identification and professional identification via emotional exhaustion. In addition, job meaningfulness may have a buffering effect on the negative impact of work-family conflict on emotional exhaustion, organizational identification, and professional identification. CONCLUSIONS/IMPLICATIONS FOR PRACTICE: The results advance knowledge on how and when work-family conflict damages organizational identification and professional identification. Providing family support, relieving emotional exhaustion, and enhancing job meaningfulness are necessary to support the organizational and professional identification of nurses.
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Esgotamento Profissional , Enfermeiras e Enfermeiros , Esgotamento Profissional/psicologia , China , Conflito Familiar , Humanos , Satisfação no Emprego , Inquéritos e QuestionáriosRESUMO
The cognitive impairment of pituitary adenomas (PAs) has received increasing attention. Hyperprolactinemia and tumor mass effect are the potential causes. The aim of this study was to identify possible cognitive impairment and to further explore the correlation between these indices and prolactin (PRL) levels, based on the control of tumor size. Twenty-seven patients with prolactinomas (patient group) and twenty-six matched health control group (HC group) were enrolled in this study. All participants performed the flanker task while we continuously recorded electroencephalography data. On the behavioral performance level, patients showed a significantly slower reaction time (RT) in both flanker types. Concerning the event-related potentials level, patients elicited reduced P2 and enhanced N2 amplitudes compared with the HC group, suggesting an impairment of attentional processing (P2) and conflict monitoring (N2). Moreover, the patient group also induced lower P3 amplitudes relative to the HC group in both types, indicating that there were deficits in attentional resource allocation ability. We also found a significant correlation between the P3 amplitudes and incongruent condition RTs, as well as the subsequent PRL levels in the patient group. In conclusion, this is an innovative study that reveals the impaired cognition abilities in prolactinomas, and also proposes the possible cognitive toxicity of oversecreted PRL levels, which provides evidence for further research on the cognitive decline in PAs.
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Repeated subconcussive head impacts are frequently experienced by athletes involved in competitive sports, such as boxing. The objective of the present study was to investigate the changes in working memory performance and memory retrieval-related neural oscillations in boxing athletes who experienced repeated subconcussive head impacts. Twenty-one boxing athletes (boxing group) and 25 matched controls (control group) completed a modified visual working memory task, and their continuous scalp electroencephalography (EEG) data were collected simultaneously. The behavioral measures and retrieval-related low-frequency neural oscillations were analyzed at each working memory set size in both groups. Subjects in the boxing group showed a reduced mean accuracy, diminished capacity estimates, and slower reaction time at demanding set sizes, and a marginally increased intra-individual coefficient of variation (ICV) for overall set sizes. Additionally, decreased event-related frontal theta synchronization, parieto-occipital alpha desynchronization, and frontal low beta synchronization were observed in the boxing group, suggesting underlying working memory dysfunction for efficient neurocognitive resource employment, inhibition of distracting stimuli, and post-retrieval control in the boxing group. Moreover, a negative correlation was found between frontal beta synchronization and reaction time for most set sizes in both groups. The present study was the first to reveal the underlying working memory deficits caused by the cumulative effects of boxing-related subconcussive head impacts from the perspective of behavior and EEG time-frequency oscillations. Joint analysis of EEG low-frequency oscillations and the innovative task with multiple challenging load conditions may serve as a promising way to detect concealed deficiencies within working memory processing.
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Eletroencefalografia , Memória de Curto Prazo , Cognição , Humanos , Transtornos da Memória , Memória de Curto Prazo/fisiologia , Tempo de Reação/fisiologiaRESUMO
Cognitive abilities are impaired in patients with pituitary adenoma. However, studies on attention processing impairment in preoperative patients and attention processing recovery after transsphenoidal adenomectomy are lacking. The study aims to identify the electrophysiological change that relates to attention processing in pituitary patients before and after treatment. Twenty five preoperative pituitary patients and 25 follow-up postoperative patients were recruited. 27 healthy controls (HCs) were matched to the patients with age, gender, and education. Event-related potentials were used to investigate the attention processing in the preoperative patients, postoperative patients, and HCs. Across three groups, all emotional stimuli evoked P200 components. Compared with the HCs or postoperative patients, the amplitudes of P200 in the preoperative patients were higher. Moreover, The amplitudes of P200 decreased in the postoperative patients, which were similar to that in the HCs. The attention processing was improved after surgery, but no significant differences were detected between the postoperative patients and HCs. Abnormal hormone levels may be relevant to the factor that impair attention processing. Compared with that of the HCs and postoperative patients, the P200 component elicited by negative stimuli is higher in preoperative patients, which may illustrate compensatory activity after attention impairments. Furthermore, these data indicate that improvements in attention processing may be attributed to the amelioration of endocrine disorders. This study shows that the P200 component may be used to diagnose attention processing in preoperative pituitary patients and prove the improvement of attention processing in postoperative patients.
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Prolactinomas have been reported for the failure of cognitive functions. However, the electrophysiological mechanisms of attention processing in prolactinomas remain unclear. In a visual mission, we monitored the scalp electroencephalography (EEG) of the participants. Compared with the healthy controls (HCs), larger frontoparietal theta and alpha coherence were found in the patients, especially in the right-lateralized hemisphere, which indicated a deficit in attention processing. Moreover, the frontoparietal coherence was positively correlated with altered prolactin (PRL) levels, implying the significance of PRL for adaptive brain compensation in prolactinomas. Taken together, this research showed the variations in attention processing between the HCs and prolactinomas. The coherence between frontal and parietal regions may be one of the possible electrophysiological biomarkers for detecting deficient attention processing in prolactinomas.
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Cognitive impairment caused by repetitive subconcussion has received increasing attention in recent years. Although the dysfunction of attention has been confirmed by neuropsychological research using scales, there is no event-related potentials (ERPs) research. The Attention Network Test (ANT) has been widely used to evaluate the three separate components of attention processing (alerting, orienting, and executive control). Twenty-seven paratroopers exposed to repetitive subconcussion (subconcussion group) and 25 matched healthy control participants (HCs group) were enrolled, and all of them performed the ANT test while continuous scalp electroencephalography data were recorded. On the behavioral performance level, the subconcussion group showed a slower task response, with an especially significant slower reaction time in alerting. Concerning ERP results, reduction amplitudes of cue-N1 in the alerting network were observed, indicating that this group was less able to make efficient use of cues and maintain an alerting state for incoming information. For the orienting network, no difference in N1 amplitude was observed between the two groups. Moreover, there was a reduced P3 amplitude in the executive control network in the subconcussion group compared with the HCs group, suggesting a dysfunction of attentional resource allocation and inhibition control in the former group. This study is, to our knowledge, the first analysis of the altered attention network caused by repetitive subconcussion from the perspectives of behavioral and neuropsychology levels. These preliminary results revealed the possible damage of the alerting and executive control networks and provided a reference for further research on subconcussion cognitive impairment.
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Atenção/fisiologia , Aviação , Concussão Encefálica/fisiopatologia , Disfunção Cognitiva/fisiopatologia , Potenciais Evocados/fisiologia , Função Executiva/fisiologia , Militares , Rede Nervosa/fisiopatologia , Doenças Profissionais/fisiopatologia , Orientação/fisiologia , Adulto , Concussão Encefálica/complicações , Disfunção Cognitiva/etiologia , Eletroencefalografia , Humanos , Masculino , Doenças Profissionais/etiologia , Adulto JovemRESUMO
The COVID-19 pandemic has unhinged the lives of people across the globe. In particular, more than 30 million Chinese college students are home-schooling, yet there is little understanding of how academic workload, separation from school, and fears of contagion lead to a decrease in their health. This study examined the relationships between Chinese college students' three critical stressors and two types of health in the COVID-19 pandemic context. We used a three-wave lagged design with a one-week interval. All the constructs were assessed by self-report in anonymous surveys during the COVID-19 pandemic. College students were asked to report their demographic information, academic workload, separation from school, fears of contagion, perceived stress, and health. The results of this study showed that academic workload, separation from school, and fears of contagion had negative effects on college students' health via perceived stress. In the COVID-19 crisis, multiple prevention and control measures focusing on college students may lead them to have different degrees of stress and health problems. Our results enrich the literature on stress and health and offer novel practical implications for all circles of the society to ensure students' health under the context of the COVID-19 epidemic.
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COVID-19/transmissão , Estresse Psicológico/epidemiologia , Estudantes/psicologia , COVID-19/psicologia , China , Estudos Transversais , Educação a Distância , Feminino , Humanos , Masculino , Saúde Mental , Estresse Psicológico/etiologia , UniversidadesRESUMO
Objective: In December 2019, a novel coronavirus infectious disease, coronavirus disease 2019 (COVID-19), began to appear in China. Wuhan, Hubei Province, is the origin and core location of the epidemic. Neurosurgeons were faced with the challenge of balancing treatment of patients with life-threatening conditions and preventing the cross-transmission of the virus. Methods: A series of infection prevention and control strategies was adopted for the peri-operative period of emergency surgeries in our department. These strategies include protective measures for the emergency department (ED) and measures for the peri-operative period of emergency surgery. The propensity score matching (PSM) was used to match COVID-19-related patients with patients before the epidemic. Length of wait time in the ED and duration of operation were compared. Results: From January 23, 2020 to March 18, 2020, we performed emergency surgery for 19 patients who were either COVID-19-related or COVID-19-suspected. None of the medical staff involved in the surgeries developed viral infection, and no peri-operative virus transmission occurred in our hospital. After the PSM, 32 patients were included in the epidemic group and the pre-epidemic group (16 patients in each group). The duration of wait time in the ED of the former group was longer than that of the latter group (z = -3.000; p = 0.003). During the epidemic, the duration of a craniotomy was longer than before the epidemic (z = -2.253; p = 0.024), and there was no difference in the duration of interventional surgery (z = -0.314; p = 0.753). Conclusion: We believe that our experience can provide a useful reference for other surgeons facing the same challenges and as a lesson for similar infectious diseases that may occur in the future.
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COVID-19/epidemiologia , COVID-19/prevenção & controle , Controle de Infecções/métodos , Procedimentos Neurocirúrgicos/métodos , Período Perioperatório , Adolescente , Adulto , Idoso , China/epidemiologia , Infecção Hospitalar/prevenção & controle , Meio Ambiente , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Equipamento de Proteção Individual/normas , Equipamento de Proteção Individual/provisão & distribuição , SARS-CoV-2 , Adulto JovemRESUMO
Based on the conservation of resource theory, we proposed a two-path model to examine the double-edged sword effects of career calling on occupational embeddedness via work-family conflict (WFC) and career adaptability. The proposed theoretical model and hypotheses were tested by structural equation modeling technology with a sample of nurses from five hospitals in China (total N = 368). Career calling has a double-edged sword effect on occupational embeddedness via WFC and career adaptability. Career calling has positive effects on WFC and career adaptability. WFC and career adaptability, in turn, negatively and positively influence occupational embeddedness, respectively. In addition to the well-established positive effects, career calling may also have adverse effects on occupational outcomes. Given the worldwide shortage of nursing staff, how career calling affects nurses' occupational embeddedness needs to be more understood. This study highlights the importance of career calling and occupational embeddedness. Nurse managers need to improve the level of nurses' career adaptability and reduce their level of WFC and hence increase their occupational embeddedness.