Prevalence and related factors for neck pain in military personnel: a systematic review.

Purpose: In the military, neck pain is second to low back pain among musculoskeletal disorders. However, the prevalence and related factors of neck pain in military personnel have not been systematically investigated, which may lead to the lack of neck pain prevention and the generation of additional medical expenses, posing challenges to medical care. This review aimed to obtain the prevalence and related factors for neck pain in military personnel in an attempt to provide directions for prevention and intervention. Methods: We searched PubMed, Embase, and Cochrane databases in December 2021. Two researchers independently screened studies according to eligibility criteria and assessed study quality. Results: We screened titles and abstracts of 503 articles, and 17 articles met the inclusion criteria. Sixteen articles received moderate to high-quality evaluations. Neck pain is common in the military, with 1-year prevalence as high as 83% and lifetime prevalence as high as 78%. Old age (OR = 5.0), poor neck mobility (OR = 3.61), shoulder pain (OR = 4.9), low back pain (OR = 2.3), high-G pilots (OR = 1.6), longer flight time (OR = 2.53), type of aircraft (OR = 3.93), and use of helmets and night vision systems (OR = 1.9) may be associated with the prevalence of neck pain. Conclusion: Neck pain is highly prevalent in military personnel and exhibits a substantial lifetime prevalence rate. The high prevalence rate of neck pain in the military is related to many individual-related factors and work-related factors. The in-depth assessment and prevention of specific factors is an important direction of future research.

Oxygen Vacancy Enabled Electronic Structure Engineering of Pt-WO3 Nanosheets toward Highly Efficient BTEX Sensing.

A Pt nanoparticle-immobilized WO3 material is a promising candidate for catalytic reactions, and the surface and electronic structure can strongly affect the performance. However, the effect of the intrinsic oxygen vacancy of WO3 on the d-band structure of Pt and the synergistic effect of Pt and the WO3 matrix on reaction performance are still ambiguous, which greatly hinders the design of advanced materials. Herein, Pt-decorated WO3 nanosheets with different electronic metal-support interactions are successfully prepared by finely tuning the oxygen vacancy structure of WO3 nanosheets. Notably, Pt-modified WO3 nanosheets annealed at 400 °C exhibit excellent benzene series (BTEX) sensing performance (S = 377.33, 365.21, 348.45, and 319.23 for 50 ppm ethylbenzene, benzene, toluene, and xylene, respectively, at 140 °C), fast response and recovery dynamics (10/7 s), excellent reliability (σ = 0.14), and sensing stability (φ = 0.08%). Detailed structural characterization and DFT results reveal that interfacial Ptδ+-Ov-W5+ sites are recognized as the active sites, and the oxygen vacancies of the WO3 matrix can significantly affect the d-band structure of Pt nanoparticles. Notably, Pt/WO3-400 with improved surface oxygen mobility and medium electronic metal-support interaction facilitates the activation and desorption of BTEX, which contributes to the highly efficient BTEX sensing performance. Our work provides a new insight for the design of high-performance surface reaction materials for advanced applications.

Development of a Decision Aid for Family Surrogate Decision Makers of Critically Ill Patients Requiring Renal Replacement Therapy in ICU: A User-Centered Design for Rapid Prototyping.

Objectives Renal replacement therapy (RRT) is increasingly adopted for critically ill patients diagnosed with acute kidney injury, but the optimal time for initiation remains unclear and prognosis is uncertain, leading to medical complexity, ethical conflicts, and decision dilemmas in intensive care unit (ICU) settings. This study aimed to develop a decision aid (DA) for the family surrogate of critically ill patients to support their engagement in shared decision-making process with clinicians. Methods Development of DA employed a systematic process with user-centered design (UCD) principle, which included: (i) competitive analysis: searched, screened, and assessed the existing DAs to gather insights for design strategies, developmental techniques, and functionalities; (ii) user needs assessment: interviewed family surrogates in our hospital to explore target user group's decision-making experience and identify their unmet needs; (iii) evidence syntheses: integrate latest clinical evidence and pertinent information to inform the content development of DA. Results The competitive analysis included 16 relevant DAs, from which we derived valuable insights using existing resources. User decision needs were explored among a cohort of 15 family surrogates, revealing four thematic issues in decision-making, including stuck into dilemmas, sense of uncertainty, limited capacity, and delayed decision confirmation. A total of 27 articles were included for evidence syntheses. Relevant decision-making knowledge on disease and treatment, as delineated in the literature sourced from decision support system or clinical guidelines, were formatted as the foundational knowledge base. Twenty-one items of evidence were extracted and integrated into the content panels of benefits and risks of RRT, possible outcomes, and reasons to choose. The DA was drafted into a web-based phototype using the elements of UCD. This platform could guide users in their preparation of decision-making through a sequential four-step process: identifying treatment options, weighing the benefits and risks, clarifying personal preferences and values, and formulating a schedule for formal shared decision-making with clinicians. Conclusions We developed a rapid prototype of DA tailored for family surrogate decision makers of critically ill patients in need of RRT in ICU setting. Future studies are needed to evaluate its usability, feasibility, and clinical effects of this intervention.

Associations between Physical Activity and the Incidence of Cerebrovascular Disease or All-Cause Mortality among 146,742 Older Adults: A 13-Year Prospective Cohort Study.

OBJECTIVES: Although studies have indicated that physical activity (PA) is related to cardiovascular disease, the specific association between PA and incident cerebrovascular disease (CBVD) remains uncertain. The current study aimed to investigate the associations between PA levels and the CBVD incidence or all-cause mortality. DESIGN: Prospective cohort study. SETTINGS AND PARTICIPANTS: Older participants (aged >60 years) from the UK Biobank. METHODS: The baseline PA was classified as total, light, moderate, and vigorous PA based on the metabolic equivalent-minutes per week (MET-min/wk) and considered as exposures, whereas CBVD incidence and all-cause mortality were considered as the outcomes. Cox proportional hazards were used to calculate the hazard ratios (HRs) and 95% CIs for the influence of the association between PA and CBVD incidence and all-cause mortality. RESULTS: A total of 146,742 participants aged 60 years and older were included. During a median follow-up period of 13.5 years (interquartile range of 12.8-14.2), 9338 older individuals developed CBVD and 3033 death were recorded (including 767 CBVD-related deaths). High volumes of PA were consistently associated with lower risks of CBVD and all-cause mortality. The lowest risk of CBVD incidence was observed at 2001-2500 MET-min/wk of total PA (HR 0.61, 95% CI 0.53-0.70), and the lowest risk of all-cause mortality was observed at 2501-5000 MET-min/wk (HR 0.52, 95% CI 0.43-0.63) in older adults. Total PA at 2001-2500 MET-min/wk significantly reduced the CBVD incidence in older women (HR 0.57, 95% CI 0.46-0.71), which was more pronounced than that in older men (HR for 2001-2500 MET-min/wk: 0.64, 95% CI 0.50-0.77). CONCLUSIONS AND IMPLICATIONS: Total PA at 2001-2500 MET-min/wk significantly reduced the risk of incident CBVD and all-cause mortality in adults aged >60 years, although the extents of risk reduction vary in men and women.

Associations between back pain incidence, and physical activity and sedentary behaviours: A prospective cohort study with data from over 365,000 participants.

OBJECTIVE: To examine the associations between (i) various types of physical activity and the risk of back pain incidence, and (ii) the influence of substituting sedentary behaviours with physical activities on back pain incidence. DESIGN: A prospective cohort study. METHODS: We analyzed UK Biobank data collected from 365,307 participants who were free of back pain at baseline. The exposures were total, light, moderate and vigorous physical activity, and sedentary behaviours. The outcome was back pain incidence. The main statistical models were the Cox proportional hazard model and the isotemporal substitution model. RESULTS: In the follow-up time (median, 12.97 years; inter-quartile range, 12.10-13.71), 25,189 individuals developed back pain. The associations between all types of physical activity and incident back pain were significantly non-linear (p < 0.001) among the general population and other subgroups. High physical activity was associated with a decreased risk of back pain compared with no physical activity. The lowest risk occurred in the 1801-2400 MET-min/week subgroup of total physical activity (HR 0.64, 95% CI 0.59-0.69), approximately consisting of 1200, 600, and 600 MET-min/week of light, moderate and vigorous physical activity, respectively. Extremely high vigorous physical activity was related to high risk, specifically in males (HR 1.13, 95% CI 1.02-1.25). Replacing 1 hour/day of sedentary behaviours with an equal time of physical activity reduced the risk of incident back pain by 2%-8% (p < 0.05). CONCLUSION: Physical activity was related to a reduced risk of back pain incidence (except over-high vigorous physical activity). Substituting sedentary behaviours with physical activities reduced the risk of future back pain.

Demographic and clinical characteristics associated with failure of physical therapy in chronic low back pain: a secondary analysis from a randomized controlled trial.

BACKGROUND: The effect of physical therapy on pain and disability alleviation in patients with chronic low back pain (cLBP) has been demonstrated, but the risk factors for treatment failure remain unknown. AIM: To explore the associations of baseline demographic and clinical characteristics with treatment failure after physical therapy intervention for cLBP. DESIGN: A secondary analysis of a single-blind randomized clinical trial. SETTING: A rehabilitation hospital. POPULATION: A total of 98 patients with cLBP completed the 12-month measurement. METHODS: Patients were randomly grouped into 3-month therapeutic aquatic exercise or physical therapy modalities. The primary outcome was treatment failure, which was defined as a decrease in the numeric rating scale to less than 2.0 points at 12-month follow-up. Associations between baseline demographic and clinical characteristics with risk of treatment failure were assessed by logistic regressions. RESULTS: The pain intensity in the failure cases was alleviated after 3-month intervention but continuously increased at 6- and 12-month follow-up (P<0.05). Old age was significantly associated with an increased risk of treatment failure (adjusted OR 3.26, 95% CI 1.11-9.60). Compared with those receiving physical therapy modalities, the patients receiving therapeutic aquatic exercise had less risk of treatment failure (adjusted OR 0.19, 95% CI 0.08-0.47), and age (P=0.022) was a modifier for this association. CONCLUSIONS: Compared with younger ones, older patients with cLBP had a higher risk of treatment failure after physical therapy and gained a stronger benefit of long-term pain alleviation from therapeutic aquatic exercise. CLINICAL REHABILITATION IMPACT: Therapeutic aquatic exercise is an effective therapy for cLBP and more helpful for preventing treatment failure than physical therapy modalities, especially for older patients.

Efficient biosynthesis of prunin in methanol cosolvent system by an organic solvent-tolerant α-L-rhamnosidase from Spirochaeta thermophila.

Prunin of desirable bioactivity and bioavailability can be transformed from plant-derived naringin by the key enzyme α-L-rhamnosidase. However, the production was limited by unsatisfactory properties of α-L-rhamnosidase such as thermostability and organic solvent tolerance. In this study, biochemical characteristics, and hydrolysis capacity of a novel α-L-rhamnosidase from Spirochaeta thermophila (St-Rha) were investigated, which was the first characterized α-L-rhamnosidase for Spirochaeta genus. St-Rha showed a higher substrate specificity towards naringin and exhibited excellent thermostability and methanol tolerance. The Km of St-Rha in the methanol cosolvent system was decreased 7.2-fold comparing that in the aqueous phase system, while kcat/Km value of St-Rha was enhanced 9.3-fold. Meanwhile, a preliminary conformational study was implemented through comparative molecular dynamics simulation analysis to explore the mechanism underlying the methanol tolerance of St-Rha for the first time. Furthermore, the catalytic ability of St-Rha for prunin preparation in the 20% methanol cosolvent system was explored, and 200 g/L naringin was transformed into 125.5 g/L prunin for 24 h reaction with a corresponding space-time yield of 5.2 g/L/h. These results indicated that St-Rha was a novel α-L-rhamnosidase suitable for hydrolyzing naringin in the methanol cosolvent system and provided a better alternative for improving the efficient production yield of prunin.

Reliability and Validity of the Star Excursion Balance Test for Evaluating Dynamic Balance of Upper Extremities.

BACKGROUND: Upper extremity (UE) dynamic balance is a significant physical fitness ability, which includes high-level neuromuscular proprioception, joint mobility, force, and coordination. The evaluation methods of UE dynamic balance are insufficient and lack experimental support. The Star Excursion Balance Test (SEBT) is a reliable assessment of dynamic balance and injury risk of the lower extremity. HYPOTHESIS: The UE-SEBT is a reliable and reproducible approach for evaluating dynamic balance of UEs. STUDY DESIGN: Observational study. LEVEL OF EVIDENCE: Level 4. METHODS: This cross-sectional study recruited 65 healthy adults. All participants were required to complete UE-SEBT, UE Y-balance test (UE-YBT), maximal voluntary isometric contraction (MVIC) of UE, closed kinetic chain UE stability test (CKCUEST), trunk flexor endurance test (TFET), trunk extensor endurance test (TEET), and lateral trunk endurance test (LTET). Intra- and inter-rater reliability and the correlation of UE-SEBT with other outcomes were measured. RESULTS: Among the participants, the intra- and interoperator reliability of UE-SEBT in all directions and composite score achieved a moderate-to-excellent (intraclass correlation coefficients [ICC], 0.729-0.946) reliability. For validity, the UE-SEBT had a moderate to very strong correlation with UE-YBT (r = 0.315-0.755, P < 0.01) and a strong correlation with CKCUEST (r = 0.4-0.67, P < 0.01). Furthermore, the UE-SEBT performance showed weak-to-strong correlations with MVIC (r = 0.26-0.43, P < 0.05). UE-SEBT was also correlated with LTET, TEET, and TFET to varying degrees. CONCLUSION: UE-SEBT has good reliability and validity to assess UE dynamic balance compared with other tests. CLINICAL RELEVANCE: UE-SEBT can be used as a clinical assessment method to evaluate UE dynamic balance and injury prevention.

Pd Decoration with Synergistic High Oxygen Mobility Boosts Hydrogen Sensing Performance at Low Working Temperature on WO3 Nanosheet.

Pd-based materials have received remarkable attention and exhibit excellent H2 sensing performance due to their superior hydrogen storage and catalysis behavior. However, the synergistic effects originated from the decoration of Pd on a metal oxide support to boost the sensing performance are ambiguous, and the deep investigation of metal support interaction (MSI) on the H2 sensing mechanism is still unclear. Here, the model material of Pd nanoparticle-decorated WO3 nanosheet is synthesized, and individual fine structures can be achieved by treating it at different temperatures. Notably, the Pd-WO3-300 materials display superior H2 sensing performance at a low working temperature (110 °C), with a superior sensing response (Ra/Rg = 40.63 to 10 ppm), high sensing selectivity, and anti-interference ability. DFT calculations and detailed structural investigations confirm that the moderate MSI facilitates the generation of high mobility surface O2- (ad) species and a proper ratio of surface Pd0-Pd2+ species, which can significantly boost the desorption of intermediate PdHx species at low temperatures and contribute to enhanced sensing performance. Our work illustrates the effect of MSI on sensing performance and provides insight into the design of advanced sensing materials.

Association between smoking and incident back pain: A prospective cohort study with 438 510 participants.

Background: Although smoking is a known potential contributor to back pain, there is still a lack of quantitative studies on the effects of different doses on back pain (BP) occurrence, including a lack of a longitudinal cohorts. To address this gap, we aimed to investigate the association between various smoking-related exposures and back pain incidence to advance global efforts toward smoking cessation and guide primary prevention of BP. Methods: In this prospective cohort study, we retrieved data on 438 510 patients from the UK Biobank who were free of back pain and who were recruited in 2006-2010, and followed them up from baseline through 1 April 2022. We extracted data on smoking-related exposures, including smoking status (SS), number of cigarettes smoked daily (CPD), and pack-years of own smoking (PY) and examined back pain incidence as an outcome. We used a Cox proportional hazard model adjusted for several covariates, multiple imputation methods, and population attribution fraction. Results: During the median follow-up of 12.98 years, 31 467 participants developed BP, with incidence rates in former and current smokers of 1.13 (95% confidence interval (CI) = 1.10-1.16, P < 0.000) and 1.50 (95% CI = 1.45-1.56, P < 0.000), respectively. The hazard ratios (HRs) of participants who smoked more than 30 CPD and those with more than 30 PY were 1.45 (95% CI = 1.36-1.55, P < 0.000) and 1.45 (95% CI = 1.40-1.50, P < 0.000), respectively. Relative to male, female smokers were at more risk of developing BP. Not smoking, quitting smoking, and reducing CPD and PY could lower the BP risk by 7.8%, 5.4%, 9.8%, and 18.0%, respectively. Conclusions: Ever smoking, higher cigarette consumption daily, and increased smoking intensity were associated with an increased BP risk. This association was stronger in female smokers. Not smoking, smoking cessation, and reducing smoking volume and intensity were effective measures to prevent BP occurrence.

Spinal posture assessment and low back pain.

Postural assessment can help doctors and therapists identify risk factors for low back pain and determine appropriate follow-up treatment. Postural alignment is not perfectly symmetrical, and small asymmetries can instead represent norms and criteria for postural evaluation. It is necessary to comprehensively observe patients' posture in all directions and analyze the factors related to posture evaluation. The results of reliability show that in general intra-rater reliability is higher than inter-rater reliability, and inclinometers are being more reliable than other instrumentations. Some common postural problems can cause lumbar discomfort, and prolonged poor posture is a potential risk factor for lumbar spine injuries. On the basis of previous studies on posture evaluation, a unified standardized method for posture evaluation must be established in future research.

The effect and mechanism of motor control exercise on low back pain: a narrative review.

Low back pain (LBP) is a common symptom that can occur in all ages. It is the first common cause of disability globally and is associated with over 60 million disability-adjusted life-years in a single year. Motor control exercise (MCE) has obtained increasing attention in treating LBP. However, the findings from distinct meta-analyses differed and some even reached controversial conclusions. More importantly, how MCE improves LBP-related symptoms remains unclear. The primary aim of this study is to describe the possible improvement mechanisms of MCE on LBP from brain, biochemistry, inflammatory, and neuromuscular aspects. The secondary aim is to further conclude its effectiveness and clinical application. Further understanding of mechanisms and effectiveness could be instructive for future LBP treatments and provide more information for clinicians when making prescriptions. MCE is effective in alleviating pain and disability among patients with acute and chronic LBP. Notably, the evidence for acute LBP is relatively low-quality and limited. MCE might be more effective for patients with specific LBP characteristics, especially those with pre-diagnosis of impaired transversus abdominis recruitment, intermediate pain intensity, and longer MCE training duration. MCE could remap brain representation and reverse negative brain alternation, induce exercise-induced hypoalgesia, mediate anti-inflammatory response, retain normal activation, and improve morphological deficits.

Contributory roles of sarcopenia and myosteatosis in development of overt hepatic encephalopathy and mortality after transjugular intrahepatic portosystemic shunt.

BACKGROUND: Skeletal muscle abnormalities, such as muscle mass depletion (sarcopenia) and fatty infiltration of the muscle (myosteatosis), are frequent complications in cirrhotic patients scheduled for transjugular intrahepatic portosystemic shunt (TIPS). AIM: To investigate the association and predictive value of sarcopenia and myosteatosis for overt hepatic encephalopathy (HE) and mortality after TIPS. METHODS: The records of cirrhotic patients who underwent the TIPS procedure at our hospital between January 2020 and June 2021 were retrospectively retrieved. The transversal psoas muscle thickness (TPMT) and psoas muscle attenuation (PMA) measured from the unenhanced abdominal computed tomography (CT) at the level of the third lumbar vertebrae were used to analyze the sarcopenia and myosteatosis, respectively. The area under curve (AUC) was used to evaluate the discriminative power of TPMT, PMA, and relevant clinical parameters. Fur-thermore, log-rank test was performed to compare the incidence of overt HE and survival between the different groups, and the association of risk factors with overt HE and mortality was analyzed using Cox proportional hazards regression models. RESULTS: A total of 108 patients were collected. Among these patients, 45.4% of patients developed overt HE after TIPS treatment. Furthermore, 32.4% and 28.7% of these patients were identified to have myosteatosis and sarcopenia, respectively. Myosteatosis (51.0% vs 16.9%, P < 0.001) and sarcopenia (40.8 vs 18.6%, P = 0.011) were found to be more frequent in patients with overt HE, when compared to patients without overt HE. The receiver operating characteristics analysis indicated that the predictive power of TPMT and PMA in overt HE (AUC = 0.713 and 0.778, respectively) was higher when compared to the neutrophil lymphocyte ratio (AUC = 0.636). The cumulative incidence of overt HE was the highest in patients with concomitant sarcopenia and myosteatosis, followed by patients with myosteatosis or sarcopenia, while this was the lowest in patients without sarcopenia and myosteatosis. In addition, sarcopenia and myosteatosis were inde-pendently associated with overt HE and mortality after adjusting for confounding factors in post-TIPS patients. CONCLUSION: CT-based estimations for sarcopenia and myosteatosis can be used as reliable predictors for the risk of developing overt HE and mortality in cirrhotic patients after TIPS.

Validity and reliability of upper extremity star excursion balance test in adolescent swimmers.

Background: Upper limb balance is one of the important physical fitness parameters for all populations, especially overhead athletes like swimmers. Upper extremity star excursion balance test (UESEBT) is a comprehensive dynamic balance assessment, this study aims to explore the reliability and validity of UESEBT among adolescent swimmers. Methods: This cross-sectional study recruited 70 adolescent swimmers. All participants were required to complete UESEBT, upper quarter Y-balance test (UQYBT), maximal isometric strength (MIS) tests in upper limb, closed kinetic chain upper extremity stability test (CKCUEST), trunk flexor endurance test (TFET) and lateral trunk endurance test (LTET). The intra- and inter-operator reliability and the correlation of UESEBT with other physical performances were conducted. Results: For reliability, the intra- and inter-operator reliability of all directions and composite score were high-to-excellent (ICC = 0.706-1.000) among all participants. For validity, the UESEBT has a moderate-to-strong correlation with UQYBT (r = 0.42-0.72, p < 0.001), and a weak-to moderate one with CKCUEST (r = 0.25-0.42, p < 0.05). Furthermore, the UESEBT performance showed weak-to-moderate correlations with MIS (r = 0.24-0.44, p < 0.05). UESEBT was correlated to LTET (r = 0.24-0.33, p < 0.05) whereas no relationship was found with TFET. Conclusions: UESEBT was a reliable and valid tool to screen upper extremity dynamic balance among adolescent swimmers. UESEBT provides more detailed information in eight directions to assess the upper limb sport performance. Further study should explore the prediction ability of UESEBT for injury.

Comprehensive treatment strategy for diesel truck exhaust.

At present, diesel vehicles still play an irreplaceable role in the traditional energy field in China. Diesel vehicle exhaust contains hydrocarbons, carbon monoxide, nitrogen oxides, and particulate matter, which can lead to haze weather, photochemical smog, and the greenhouse effect; endanger human health; and damage the ecological environment. In 2020, the number of motor vehicles in China reached 372 million, and the number of automobiles reached 281 million, of which 20.92 million are diesel vehicles, accounting for only 5.6% of the number of motor vehicles and 7.4% of the number of automobiles. Nevertheless, diesel vehicles emitted 88.8% of nitrogen oxides and 99% of particulate matter in total vehicle emissions. Diesel vehicles, especially diesel trucks, have become the top priority of motor vehicle pollution control. However, there are few reviews on the comprehensive treatment of diesel vehicle exhaust. This review provides an overview of exhaust gas composition, hazards, and treatment techniques. Phytoremediation, three-way catalytic conversion, rare earth catalytic degradation, and nanoscale TiO2 catalytic degradation are briefly described.

Association Between Smoking and Pain, Functional Disability, Anxiety and Depression in Patients With Chronic Low Back Pain.

Objectives: Chronic low back pain (CLBP) accounts for a majority of the disability associated with LBP, which can produce long-term negative effects. This cross-sectional study aimed to investigate the association between smoking and pain, dysfunction and psychological status in patients with CLBP. Methods: The 54 patients with CLBP were recruited and divided into smoking and non-smoking groups. Their pain, dysfunction, anxiety, depression, fear and quality of life were evaluated. The amount of cigarettes smoked daily was recorded. Results: Significant differences in VAS, ODI, RMDQ and FABQ and the impact of LBP on life and work were found between smoking and non-smoking patients. In addition, a correlation was found between the daily cigarette smoking amount and VASmax, FABQtotal, SDS and FABQ-W. Moreover, a correlation was observed between the amount of cigarettes smoked daily and the degree of impact of low back pain on work. Conclusion: The study found that smoking affected the aggravation of symptoms in patients with CLBP, which indicated that patients with CLBP and people at risk of LBP should be aware of the harm caused by smoking.

A Novel κ-Carrageenase from Marine Bacterium Rhodopirellula sallentina SM41: Heterologous Expression, Biochemical Characterization and Salt-Tolerance Mechanism Investigation.

κ-carrageenases are members of the glycoside hydrolase family 16 (GH16) that hydrolyze sulfated galactans in red algae, known as κ-carrageenans. In this study, a novel κ-carrageenase gene from the marine bacterium Rhodopirellula sallentina SM41 (RsCgk) was discovered via the genome mining approach. There are currently no reports on κ-carrageenase from the Rhodopirellula genus, and RsCgk shares a low identity (less than 65%) with κ- carrageenase from other genera. The RsCgk was heterologously overexpressed in Escherichia coli BL21 and characterized for its enzymatic properties. RsCgk exhibited maximum activity at pH 7.0 and 40 °C, and 50% of its initial activity was retained after incubating at 30 °C for 2 h. More than 70% of its activity was maintained after incubation at pH 6.0-8.0 and 4 °C for 24 h. As a marine derived enzyme, RsCgk showed excellent salt tolerance, retaining full activity in 1.2 M NaCl, and the addition of NaCl greatly enhanced its thermal stability. Mass spectrometry analysis of the RsCgk hydrolysis products revealed that the enzyme had high degradation specificity and mainly produced κ-carrageenan disaccharide. Comparative molecular dynamics simulations revealed that the conformational changes of tunnel-forming loops under salt environments may cause the deactivation or stabilization of RsCgk. Our results demonstrated that RsCgk could be utilized as a potential tool enzyme for efficient production of κ-carrageenan oligosaccharides under high salt conditions.

Twisted Fiber Optic SPR Sensor for GDF11 Concentration Detection.

There are few methods and insufficient accuracy for growth differentiation factor 11 (GDF11) concentration detection. In this paper, we designed a twisted fiber cladding surface plasmon resonance (SPR) sensor, which can achieve a high precision detection of GDF11 concentration. The new structure of the fiber cladding SPR sensor was realized by coupling the light in the fiber core to the cladding through fiber thermal fusion twisting micromachining technology; a series of functionalized modifications were made to the sensor surface to obtain a fiber sensor capable of GDF11 specific recognition. The experimental results showed when GDF11 antigen concentration was 1 pg/mL-10 ng/mL, the sensor had a detection sensitivity of 2.518 nm/lgC, a detection limit of 0.34 pg/mL, and a good log-linear relationship. The sensor is expected to play a role in the rapid and accurate concentration detection of pathological study for growth differentiation factors.

Ultra-sensitive H2S sensor based on sunflower-like In-doped ZnO with enriched oxygen vacancies.

Metal oxide sensors face the challenge of high response and fast recovery at low operating temperatures for the detection of toxic and flammable hydrogen sulfide (H2S) gases. Herein, novel In-doped ZnO with a sunflower-like structure and tunable surface properties was rationally synthesized. The substitutional In atom in the ZnO crystal can dramatically enhance the concentration of oxygen vacancies (Ov), the In-ZnO sites are responsible for fast recovery, and the formation of sub-stable sulfide intermediates gives rise to the high response towards H2S. As a result, the response of the optimized 4In-ZnO sensor is 3538.36 to 50 ppm H2S at a low operating temperature of 110 °C, which is 106 times higher than that of pristine ZnO. Moreover, the response time and recovery time to 50 ppm H2S are 100 s and 27 s, respectively, with high selectivity and stability. First-principles calculations revealed that 4In-ZnO with rich Ov exhibited higher adsorption energy for the H2S molecule than pristine ZnO, resulting in effortless H2S detection. Our work lays the foundation for the rational design of highly sensitive gas sensors through precise doping of atoms in oxygen-rich vacancies in semiconductor materials.