Actively variable-spectrum optoelectronics with black phosphorus.

Room-temperature optoelectronic devices that operate at short-wavelength and mid-wavelength infrared ranges (one to eight micrometres) can be used for numerous applications1-5. To achieve the range of operating wavelengths needed for a given application, a combination of materials with different bandgaps (for example, superlattices or heterostructures)6,7 or variations in the composition of semiconductor alloys during growth8,9 are used. However, these materials are complex to fabricate, and the operating range is fixed after fabrication. Although wide-range, active and reversible tunability of the operating wavelengths in optoelectronic devices after fabrication is a highly desirable feature, no such platform has been yet developed. Here we demonstrate high-performance room-temperature infrared optoelectronics with actively variable spectra by presenting black phosphorus as an ideal candidate. Enabled by the highly strain-sensitive nature of its bandgap, which varies from 0.22 to 0.53 electronvolts, we show a continuous and reversible tuning of the operating wavelengths in light-emitting diodes and photodetectors composed of black phosphorus. Furthermore, we leverage this platform to demonstrate multiplexed nondispersive infrared gas sensing, whereby multiple gases (for example, carbon dioxide, methane and water vapour) are detected using a single light source. With its active spectral tunability while also retaining high performance, our work bridges a technological gap, presenting a potential way of meeting different requirements for emission and detection spectra in optoelectronic applications.

Coherent many-body exciton in van der Waals antiferromagnet NiPS3.

An exciton is the bosonic quasiparticle of electron-hole pairs bound by the Coulomb interaction1. Bose-Einstein condensation of this exciton state has long been the subject of speculation in various model systems2,3, and examples have been found more recently in optical lattices and two-dimensional materials4-9. Unlike these conventional excitons formed from extended Bloch states4-9, excitonic bound states from intrinsically many-body localized states are rare. Here we show that a spin-orbit-entangled exciton state appears below the Néel temperature of 150 kelvin in NiPS3, an antiferromagnetic van der Waals material. It arises intrinsically from the archetypal many-body states of the Zhang-Rice singlet10,11, and reaches a coherent state assisted by the antiferromagnetic order. Using configuration-interaction theory, we determine the origin of the coherent excitonic excitation to be a transition from a Zhang-Rice triplet to a Zhang-Rice singlet. We combine three spectroscopic tools-resonant inelastic X-ray scattering, photoluminescence and optical absorption-to characterize the exciton and to demonstrate an extremely narrow excitonic linewidth below 50 kelvin. The discovery of the spin-orbit-entangled exciton in antiferromagnetic NiPS3 introduces van der Waals magnets as a platform to study coherent many-body excitons.

Highly Sustainable h-BN Encapsulated MoS2 Hydrogen Evolution Catalysts.

Despite the importance of the stability of the 2D catalysts in harsh electrolyte solutions, most studies have focused on improving the catalytic performance of molybdenum disulfide (MoS2) catalysts rather than the sustainability of hydrogen evolution. In previous studies, the vulnerability of MoS2 crystals is reported that the moisture and oxygen molecules can cause the oxidation of MoS2 crystals, accelerating the degradation of crystal structure. Therefore, optimization of catalytic stability is crucial for approaching practical applications in 2D catalysts. Here, it is proposed that monolayered MoS2 catalysts passivated with an atomically thin hexagonal boron nitride (h-BN) layer can effectively sustain hydrogen evolution reaction (HER) and demonstrate the ultra-high current density (500 mA cm⁻2 over 11 h) and super stable (64 h at 150 mA cm⁻2) catalytic performance. It is further confirmed with density functional theory (DFT) calculations that the atomically thin h-BN layer effectively prevents direct adsorption of water/acid molecules while allowing the protons to be adsorbed/penetrated. The selective penetration of protons and prevention of crystal structure degradation lead to maintained catalytic activity and maximized catalytic stability in the h-BN covered MoS2 catalysts. These findings propose a promising opportunity for approaching the practical application of 2D MoS2 catalysts having long-term stability at high-current operation.

A humanized ACE2 mouse model recapitulating age- and sex-dependent immunopathogenesis of COVID-19.

In the ongoing battle against coronavirus disease 2019 (COVID-19), understanding its pathogenesis and developing effective treatments remain critical challenges. The creation of animal models that closely replicate human infection stands as a critical step forward in this research. Here, we present a genetically engineered mouse model with specifically-humanized knock-in ACE2 (hiACE2) receptors. This model, featuring nine specific amino acid substitutions for enhanced interaction with the viral spike protein, enables efficient severe acute respiratory syndrome coronavirus 2 replication in respiratory organs without detectable infection in the central nervous system. Moreover, it mirrors the age- and sex-specific patterns of morbidity and mortality, as well as the immunopathological features observed in human COVID-19 cases. Our findings further demonstrate that the depletion of eosinophils significantly reduces morbidity and mortality, depending on the infecting viral dose and the sex of the host. This reduction is potentially achieved by decreasing the pathogenic contribution of eosinophil-mediated inflammation, which is strongly correlated with neutrophil activity in human patients. This underscores the model's utility in studying the immunopathological aspects of COVID-19 and represents a significant advancement in COVID-19 modeling. It offers a valuable tool for testing vaccines and therapeutics, enhancing our understanding of the disease mechanisms and potentially guiding more targeted and effective treatments.

Epidermal Growth Factor Receptor (EGFR) Inhibitors Screened from Autodisplayed Fv-Antibody Library.

Inhibitors of the epithermal growth factor receptor (EGFR) were screened from an autodisplayed Fv-antibody library using an anti-EGF antibody. The Fv-antibody library was expressed on the outer membrane of Escherichia coli, which corresponds to the heavy chain VH region of immunoglobulin G. The library was constructed by randomizing the CDR3 region of expressed VH regions (11 amino acid residues) by site-directed mutagenesis. Using an anti-EGF antibody as a screening probe, amino acid sequences (CDR3 region) with antibody binding affinity were screened from the Fv-antibody library. These amino acid sequences were considered to have similar chemical properties to EGF, which can bind to EGFR. Two autodisplayed clones with Fv-antibodies against EGFR were screened from the Fv-antibody library, and the screened Fv-antibodies were expressed as soluble proteins. The binding affinity (KD) was estimated using an SPR biosensor, and the inhibitory activity of expressed Fv-antibodies was observed for PANC-1 pancreatic tumor cells and T98G glioblastoma cells using Western blot analysis of proteins in the EGFR-mediated signaling pathway. The viability of PANC-1 and T98G cells was observed to decrease via the inhibitory activity of expressed Fv-antibodies. Finally, interactions between Fv-antibodies and EGFR were analyzed by using molecular docking simulations.

Ultrahigh-purity ammonia recovery from synthetic coke wastewater via membrane contactor: Overcoming phenolic interference and assessing cost efficiency.

Ammonia recovery from industrial wastewater using membrane contactor processes is emerging as a promising method owing to the diverse applications of ammonia. This study uniquely addressed ammonia recovery from coke plant wastewater, which is challenging due to the presence of numerous toxic and volatile phenolic compounds. Experiments were conducted using a synthetic coke plant effluent to assess the effects of various pH levels and temperatures on ammonia recovery. Specifically, the aim was to achieve high-purity ammonia recovery while minimizing the permeation of phenolic compounds. The results demonstrate that ammonia recovery in the membrane contactor processes is highly efficient, even in the presence of phenolic compounds. During temperature variations at 25 °C and 40 °C, the recovery of ammonia increased from 42.36% to 52.97% at pH 11. Additionally, increasing the pH of a feed solution from 7 to 12 significantly increased the ammonia content to 58.3%. At this pH, the recovered ammonia was of exceptional purity (>99%), with phenol, p-Cresol, and 2,4-xylenol present at negligible concentrations (0.001%, 0.002%, and 0.004%, respectively). This was attributed to the ionization of phenolic compounds at higher pH levels, which prevents their permeation through the hydrophobic membrane. The estimated cost analysis revealed that the membrane contactor process at pH 12 was approximately 1.41 times more cost-effective than conventional air-stripping processes over eight years of operating period (pH-12 membrane contactor: $19.79; pH-12 air stripping: $23.75). This study provides a detailed analysis of the optimal conditions for selective ammonia recovery from complex wastewater, highlighting both effective treatment and sustainable resource recovery and offering a superior alternative to traditional methods.

Helmet wearing and related factors among electric personal mobility device users in Korea.

Using data from the 2022 Korea Community Health Survey (n = 13 320), this study investigated helmet use and related factors among Korean adults using personal mobility devices, without distinguishing between private and hired users. Among mobility device users, 32.1% responded that they always wore a helmet. The proportion of helmet use was 35.2% among men, 25.8% among women, 29.2% among those aged 19-44 years, 42.3% among those aged 45-64 years and 26.6% among those aged 65 years or older. Furthermore, those who drank less frequently and were physically active were more likely to wear helmets. Moreover, people who always wore a seat belt when driving a car or sitting in the rear seat and people who always wore a helmet when riding a motorcycle were more likely to wear a helmet while using electric personal mobility devices. Approximately one-third of users always wore a helmet. The helmet-wearing rate was related to general characteristics such as gender and education level, and to safety behaviors such as wearing a seat belt when driving a car, sitting in the rear seat of a car, or when riding a motorcycle. In addition to considering personal characteristics investigated in this study, the helmet-wearing rate should be improved through policies or systems at the national or regional levels.

Real-Time Three-Dimensional Pedestrian Localization System Using Smartphones.

Robust and accurate three-dimensional localization is essential for personal navigation, emergency rescue, and worker monitoring in indoor environments. For localization technology to be employed in various applications, it is necessary to reduce infrastructure dependence and limit the maximum error bound. This study aims to accurately estimate the location of various people using smartphones in a building with a cloud platform-based localization system. The proposed technology is modularized in a hierarchical structure to sequentially estimate the floor and location. This system comprises four localization modules: course level detection, fine level detection (FLD), fine location tracking (FLT), and level change detection (LCD). Each module operates organically according to the current user status. The position estimation range is defined as a total of three phases, and an appropriate location estimation module suitable for the corresponding phase operates to estimate the user's location gradually and precisely. When the user's floor is determined by an FLD, the two-dimensional position of the user is estimated by an FLT module that tracks the user's position by comparing the received signal strength indicator vector sequence and radio map. Also, LCD recognizes the user's floor change and converts the user's phase. To verify the proposed technology, various experiments were conducted in a six-story building, and an average accuracy of less than 2 m was obtained.

Comment on Takakura et al. Acupuncture for Japanese Katakori (Chronic Neck Pain): A Randomized Placebo-Controlled Double-Blind Study. Medicina 2023, 59, 2141.

We are writing because we have a number of concerns about the Takakura et al. [...].

Barefoot walking improves cognitive ability in adolescents.

Walking can have a positive impact on cognitive function in adolescents. This study aimed to compare the effects of walking with sneakers and barefoot on cognitive ability in adolescents. Fifty-nine adolescent male students were included in the study and assigned to the control (n = 20), sneaker (n = 19), and barefoot (n = 20) groups. The barefoot and sneakers group performed a 40-min walking exercise four times a week for 12 weeks during the morning physical activity time, while the control group performed self-study. Electroencephalogram (EEG) and brain activity variables were measured before and after the exercise program. The results showed that after 12 weeks, the barefoot group had a significant decrease in Gamma and H-beta waves and a significant increase in sensorimotor rhythm (SMR) and Alpha waves. Conversely, the control group showed a significant decrease in SMR waves and increase in Theta waves. The sneaker group showed a significant decrease in SMR waves alone. In an eyes-open resting state, the barefoot group showed a significant increase in H-beta, M-beta, SMR, and Alpha waves. The barefoot group also had a significant increase in cognitive speed and concentration and a significant decrease in brain stress. Taken together, barefoot walking can effectively enhance cognitive ability in adolescents, as demonstrated by the significant variation in EEG activity. This research highlights the potential benefits of barefoot walking as a simple and effective form of exercise for enhancing cognitive function in adolescents.

Electrocardiogram-based deep learning algorithm for the screening of obstructive coronary artery disease.

BACKGROUND: Information on electrocardiogram (ECG) has not been quantified in obstructive coronary artery disease (ObCAD), despite the deep learning (DL) algorithm being proposed as an effective diagnostic tool for acute myocardial infarction (AMI). Therefore, this study adopted a DL algorithm to suggest the screening of ObCAD from ECG. METHODS: ECG voltage-time traces within a week from coronary angiography (CAG) were extracted for the patients who received CAG for suspected CAD in a single tertiary hospital from 2008 to 2020. After separating the AMI group, those were classified into ObCAD and non-ObCAD groups based on the CAG results. A DL-based model adopting ResNet was built to extract information from ECG data in the patients with ObCAD relative to those with non-ObCAD, and compared the performance with AMI. Moreover, subgroup analysis was conducted using ECG patterns of computer-assisted ECG interpretation. RESULTS: The DL model demonstrated modest performance in suggesting the probability of ObCAD but excellent performance in detecting AMI. The AUC of the ObCAD model adopting 1D ResNet was 0.693 and 0.923 in detecting AMI. The accuracy, sensitivity, specificity, and F1 score of the DL model for screening ObCAD were 0.638, 0.639, 0.636, and 0.634, respectively, while the figures were up to 0.885, 0.769, 0.921, and 0.758 for detecting AMI, respectively. Subgroup analysis showed that the difference between normal and abnormal/borderline ECG groups was not notable. CONCLUSIONS: ECG-based DL model showed fair performance for assessing ObCAD and it may serve as an adjunct to the pre-test probability in patients with suspected ObCAD during the initial evaluation. With further refinement and evaluation, ECG coupled with the DL algorithm may provide potential front-line screening support in the resource-intensive diagnostic pathways.

Clinical Utility of a 3D-Printed Patient-Specific Surgical Guide for Partial Nephrectomy.

Partial nephrectomy (PN) is a common surgery for small renal masses. The goal is to remove the mass completely while preserving renal function. A precise incision is, therefore, important. However, no specific method for surgical incision in PN exists, although there are several guides for bony structures using three-dimensional (3D) printing methods. Therefore, we tested the 3D printing method to create a surgical guide for PN. We describe the workflow to make the guide, which comprises computed tomography data acquisition and segmentation, incision line creation, surgical guide design, and its use during surgery. The guide was designed with a mesh structure that could be fixed to the renal parenchyma, indicating the projected incision line. During the operation, the 3D-printed surgical guide accurately indicated the incision line, without distortion. An intraoperative sonography was performed to locate the renal mass, which confirmed that the guide was well placed. The mass was completely removed, and the surgical margin was negative. No inflammation or immune reaction occurred during and 1 month after the operation. This surgical guide proved useful during PN for indicating the incision line and was easy to handle, without complications. We, therefore, recommend this tool for PN with improved surgical outcome.

Triangular Resection Epicanthoplasty: A Novel Method of Minimizing Hypertrophic Scar After Medial Epicanthoplasty.

Medial epicanthoplasty is a crucial component in Asian cosmetic eyelid surgery. Conventional surgical methods have mandated wide undermining for the purpose of sufficient release. However, excessive undermining may result in hypertrophic scar or webbing deformities. To minimize undesirable results, the authors are proposing a novel approach. From March 2010 to December 2017, a triangular resection epicanthoplasty was performed in 421 Asian patients. The authors' procedure consists of triangular skin resection, the release of orbicularis oculi muscle and upper half medial epicanthal tendon, and dog ear correction. No complication regarding scarring or webbing was reported. The revision was performed in 18 cases where the patients wanted additional correction. The triangular resection epicanthoplasty offers both optimal results and minimal scar with relative simplicity.

Intraoperative assessment of hindfoot alignment using C-arm fluoroscopy.

BACKGROUND: Hindfoot malalignment can cause various foot and ankle problems. For better surgical performance and correction of hindfoot malalignments, reliable intraoperative determination of hindfoot alignment is essential. However, there is no standard method for the intraoperative assessment of hindfoot alignment. We devised an intraoperative modified Méary posteroanterior (IOPPA) view to assess intraoperative hindfoot alignment. This study aimed to compare this intraoperative method with other radiographic hindfoot alignment measurements. METHODS: Thirty-seven patients (47 feet) with various foot and ankle conditions scheduled to undergo surgery were prospectively recruited. Before surgery, the Saltzman, long axial, and modified Méary views were taken in a controlled and standardized fashion. IOPPA views were obtained under simulated weight bearing conditions using C-arm fluoroscopy in the operating room before surgery. The relationship between the IOPPA view and the three radiographic hindfoot alignments was evaluated using Pearson's correlation. RESULTS: The mean hindfoot alignment angle was varus 3.50° (CI, varus 1.91 to 5.08) on the Saltzman view, varus 2.00° (CI, varus 0.60 to 3.39) on the long axial view, varus 0.13° (CI, valgus 1.41 to varus 1.67) on the modified Méary view, and varus 1.32° (CI, valgus 0.02 to varus 2.65) on IOPPA view. The IOPPA view and the three other hindfoot alignment views were found to be significantly correlated (r = 0.60 for the Saltzman view, r = 0.50 for the long axial view, r = 0.71 for the modified Méary view, P < .05). The intraobserver ICC (Intraclass Correlation Coefficient) value was 0.974 and interobserver ICC (Intraclass Correlation Coefficient) value was 0.988 for the IOPPA view (P < .001). CONCLUSION: There was a statistically significant correlation between the IOPPA view and the other three hindfoot alignment views. We also found that interobserver and intraobserver ICC values were excellent. This study proposes that the IOPPA view can be used as a reliable intraoperative assessment tool for hindfoot alignment. LEVEL OF EVIDENCE: Prospective study.

Homogeneous One-Step Immunoassay Based on Switching Peptides for Detection of the Influenza Virus.

In this study, a homogeneous one-step immunoassay based on switching peptides is presented for the detection of influenza viruses A and B (Inf-A and Inf-B, respectively). The one-step immunoassay represents an immunoassay method that does not involve any washing steps, only treatment of the sample. In this method, fluorescence-labeled switching peptides quantitatively dissociate from the antigen-binding site of immunoglobulin G (IgG). In particular, the one-step immunoassay based on soluble detection antibodies with switching peptides is called a homogeneous one-step immunoassay. The immunoassay developed uses switching peptides labeled with two types of fluorescence dyes (FAM and TAMRA) and detection antibodies labeled with two types of fluorescence quenchers (TQ2 for FAM and TQ3 for TAMRA). The optimal switching peptides for the detection of Inf-A and Inf-B have been selected as L1-peptide and H2-peptide. The interactions between the four kinds of switching peptides and IgG have been analyzed using computational docking simulation and SPR biosensor. The location of labeling for the fluorescence quenchers has been determined based on the distance between the fluorescence dyes of the switching peptides and the fluorescence quenchers, calculated on the basis of the efficiency of fluorescence quenching, using the Förster equation. To demonstrate the feasibility of the one-step immunoassay, binding constants (KD) have been calculated for detection antibodies against Inf-A and Inf-B with target antigens (Inf-A and Inf-B) and switching peptides (L1- and H2-peptides), using an isotherm model. The immunoassay has been demonstrated to be feasible using antigens as well as real samples of Inf-A and Inf-B with a critical cycle number (Ct). The immunoassay has also been compared to other commercially available rapid test kits for Inf-A and Inf-B and found to be far more sensitive for detection of Inf-A and Inf-B over the entire detection range.

Overexpression of CYP11A1 recovers cell cycle distribution in renal cell carcinoma Caki-1.

BACKGROUND: Clear cell renal carcinoma is commonly known for its metastasis propensity to outspread to other organs and is asymptomatic in the early stage. Recent studies have shown that deficiencies in CYP11A1 expression can lead to fatal adrenal failure if left untreated and are associated with downstream regulation in various cancer types. However, the molecular mechanisms of CYP11A1 and kidney cancer proliferation remain unclear. METHODS: Normal and renal carcinoma cell lines (HEK293 and Caki-1) were transfected with plasmid encoding CYP11A1 to overexpress the P450scc protein. Cell cycle distribution was investigated using flow cytometry. The expression of proteins related to C-Raf/ERK/JNK/p38 signaling pathways was examined using western blot. RESULTS: We observed that CYP11A1 overexpression suppressed the cyclin B1 and cell-division cycle 2 expression while cyclin-dependent kinases 2 and 4 were unaffected. Cancer cell migration and invasion were suppressed along with epithelial-intermediate metastatic markers Snail and Vimentin. In addition, in CYP11A1-overexpressing Caki-1 cells, cdc2/cyclinB1 was downregulated while the phosphorylation of cdc25c, a G2/M arrest-related upstream signal, was increased. The intrinsic-mitochondrial apoptosis markers were not significantly altered. We also identified that the C-Raf/ERK/JNK/p38 pathway is an important pro-apoptotic mechanism in CYP11A1-overexpressing cell-based models. Our results suggest that CYP11A1 overexpression recovered the disturbed cell cycle arrest distribution in renal carcinoma cell line Caki-1 through G2/M arrest and C-Raf/ERK/JNK pathway. CONCLUSIONS: Our findings may suggest promising new therapeutic targets to suppress kidney cancer proliferation without affecting normal cells, eventually improving the survival of patients with cancer.

Safety and efficacy study of laparoscopic or robotic radical surgery using an endoscopic stapler for inhibiting tumour spillage of cervical malignant neoplasms evaluating survival (SOLUTION): a multi-centre, open-label, single-arm, phase II trial protocol.

BACKGROUND: The Laparoscopic Approach to Cervical Cancer trial and Surveillance, Epidemiology, and End Results program database study demonstrated that minimally invasive radical hysterectomy was inferior to abdominal radical hysterectomy in terms of disease recurrence and survival. Among risk factors related to poor prognosis after minimally invasive surgery (MIS), tumour spillage during intracorporeal colpotomy became a significant issue. Thus, we designed this trial to evaluate the efficacy and safety of minimally invasive radical hysterectomy using an endoscopic stapler for early-stage cervical cancer. METHODS: This trial is a prospective, multi-centre, open-label, single-arm, non-inferiority phase II study. The nine organisations will participate in this trial after the approval of the institutional review board. Major eligibility criteria include women aged 20 years or older with cervical cancer stage IB1 squamous cell carcinoma, adenocarcinoma, or adenosquamous carcinoma according to the revised 2009 FIGO staging system who will undergo type B2 or C hysterectomy by MIS. The primary endpoint is the 4.5-year disease-free survival (DFS) rate between abdominal radical hysterectomy and MIS using an endoscopic stapler. For calculating the sample size, we hypothesised that the 4.5-year DFS rate after MIS using an endoscopic stapler is assumed to be the same after abdominal radical hysterectomy at 90.9%, and the non-inferiority margin was 7.2%. When we consider a three-year accrual and 4.5-year follow-up, at least 13 events must happen, requiring a total of 111 patients assuming a statistical power of 80% and the one-tailed test of 5% significance. A total of 124 patients is needed, considering a drop-out rate of 10%. DISCUSSION: We expect intracorporeal colpotomy using an endoscopic stapler may prevent tumour spillage during MIS for stage IB1 cervical cancer, showing a comparable prognosis with abdominal radical surgery. TRIAL REGISTRATION: ClinicalTrials.gov ; NCT04370496 ; registration date, May 2020.

One-step immunoassay for the detection of food-poisoning related bacteria using a switching peptide.

A one-step immunoassay was developed for five types of food-poisoning-related bacteria using a switching peptide and antibodies isolated from unimmunized horse serum. The one-step immunoassay involves mixing samples and reagents in a homogeneous solution without any washing steps. In this work, a one-step immunoassay configuration was developed using isolated antibodies labelled with an organic fluorescence quencher and a switching-peptide labelled with a fluorescent dye. The fluorescence-labelled switching-peptide was bound to the antigen-binding site of the isolated antibodies before binding to the bacteria (no fluorescence signal), and the switching-peptide dissociated from the antibodies as soon as they bound to the bacteria (fluorescence signal turns on). By quantifying the generated fluorescence signal, the one-step immunoassay presented here allows microbial detection without any washing step.

Facile one-pot iodine gas phase doping on 2D MoS2/CuS FET at room temperature.

Electronic devices composed of semiconducting two-dimensional (2D) materials and ultrathin 2D metallic electrode materials, accompanying synergistic interactions and extraordinary properties, are becoming highly promising for future flexible and transparent electronic and optoelectronic device applications. Unlike devices with bulk metal electrode and 2D channel materials, devices with ultrathin 2D electrode and 2D channel are susceptible to chemical reactions in both channel and electrode surface due to the high surface to volume ratio of the 2D structures. However, so far, the effect of doping was primary concerned on the channel component, and there is lack of understanding in terms of how to modulate electrical properties of devices by engineering electrical properties of both the metallic electrode and the semiconducting channel. Here, we propose the novel, one-pot doping of the field-effect transistor (FET) based on 2D molybdenum disulfide (MoS2) channel and ultrathin copper sulfide (CuS) electrodes under mild iodine gas environment at room temperature, which simultaneously modulates electrical properties of the 2D MoS2channel and 2D CuS electrode in a facile and cost-effective way. After one-pot iodine doping, effective p-type doping of the channel and electrode was observed, which was shown through decreased off current level, improvedIon/Ioffratio and subthreshold swing value. Our results open up possibility for effectively and conveniently modulating electrical properties of FETs made of various 2D semiconductors and ultrathin contact materials without causing any detrimental damage.

Biotransformation of C20- and C22-polyunsaturated fatty acids to 11S- and 13S-hydroxy fatty acids by Escherichia coli expressing 11S-lipoxygenase from Enhygromyxa salina.

PURPOSE: Peroxidation and reduction of 11S- and 13S-positions on C20 and C22 polyunsaturated fatty acids (PUFAs) by Escherichia coli expressing highly active arachidonate (ARA) 11S-lipoxygenase (11S-LOX) from Enhygromyxa salina with the reducing agent cysteine. RESULTS: The specific activity and catalytic efficiency of ARA 11S-LOX from E. salina were 4.1- and 91-fold higher than those of only reported ARA 11S-LOX from Myxococcus xanthus, respectively. The hydroxy fatty acids (HFAs) obtained by the biotransformation of ARA, eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA), and docosahexanoic acid (DHA) by Escherichia coli expressing 11S-LOX from E. salina in the presence of cysteine were identified as 11S-hydroxyeicosatetraenoic acid (11S-HETE), 11S-hydroxyeicosapentaenoic acid (11S-HEPE), 13S-hydroxydocosapentaenoic acid (13S-HDPA), and 13S-hydroxydocosahexaenoic acid (13S-HDHA), respectively. The recombinant cells converted 3 mM of ARA, EPA, DPA, and DHA into 2.9 mM of 11S-HETE, 2.4 mM 11S-HEPE, 1. 9 mM 13S-HDPA, and 2.2 mM 13S-HDHA in 60, 80, 120, and 120 min, corresponding to productivities of 72.5, 40.4, 18.5, and 22.4 µM min-1 and conversion yields of 96.7, 80.0, 62.3, and 74.6%, respectively. CONCLUSIONS: We report the highest concentrations, conversion yields, and productivities of 11S- and 13S-hydroxy fatty acids from C20- and C22-PUFAs achieved via E. coli expressing highly active E. salina 11S-LOX.