Development of Bio-Voltage Operated Humidity-Sensory Neurons Comprising Self-Assembled Peptide Memristors.

Biomimetic humidity sensors offer a low-power approach for respiratory monitoring in early lung-disease diagnosis. However, balancing miniaturization and energy efficiency remains challenging. This study addresses this issue by introducing a bioinspired humidity-sensing neuron comprising a self-assembled peptide nanowire (NW) memristor with unique proton-coupled ion transport. The proposed neuron shows a low Ag+ activation energy owing to the NW and redox activity of the tyrosine (Tyr)-rich peptide in the system, facilitating ultralow electric-field-driven threshold switching and a high energy efficiency. Additionally, Ag+ migration in the system can be controlled by a proton source owing to the hydrophilic nature of the phenolic hydroxyl group in Tyr, enabling the humidity-based control of the conductance state of the memristor. Furthermore, a memristor-based neuromorphic perception neuron that can encode humidity signals into spikes is proposed. The spiking characteristics of this neuron can be modulated to emulate the strength-modulated spike-frequency characteristics of biological neurons. A three-layer spiking neural network with input neurons comprising these highly tunable humidity perception neurons shows an accuracy of 92.68% in lung-disease diagnosis. This study paves the way for developing bioinspired self-assembly strategies to construct neuromorphic perception systems, bridging the gap between artificial and biological sensing and processing paradigms.

Sequential Immunizations with Influenza Neuraminidase Protein Followed by Peptide Nanoclusters Induce Heterologous Protection.

Enhancing cross-protections against diverse influenza viruses is desired for influenza vaccinations. Neuraminidase (NA)-specific antibody responses have been found to independently correlate with a broader influenza protection spectrum. Here, we report a sequential immunization regimen that includes priming with NA protein followed by boosting with peptide nanoclusters, with which targeted enhancement of antibody responses in BALB/c mice to certain cross-protective B-cell epitopes of NA was achieved. The nanoclusters were fabricated via desolvation with absolute ethanol and were only composed of composite peptides. Unlike KLH conjugates, peptide nanoclusters would not induce influenza-unrelated immunity. We found that the incorporation of a hemagglutinin peptide of H2-d class II restriction into the composite peptides could be beneficial in enhancing the NA peptide-specific antibody response. Of note, boosters with N2 peptide nanoclusters induced stronger serum cross-reactivities to heterologous N2 and even heterosubtypic N7 and N9 than triple immunizations with the prototype recombinant tetrameric (rt) N2. The mouse challenge experiments with HK68 H3N2 also demonstrated the strong effectiveness of the peptide nanocluster boosters in conferring heterologous protection.

Growth of 2D Cr2 O3 -CrN Mosaic Heterostructures with Tunable Room-Temperature Ferromagnetism.

2D magnets have generated much attention due to their potential for spintronic devices. Heterostructures of 2D magnets are interesting platforms for exploring physical phenomena and applications. However, the controlled growth of 2D room-temperature ferromagnetic heterostructures is challenging. Here, one-pot chemical vapor deposition growth of stable 2D Cr2 O3 -CrN mosaic heterostructures (MHs) is reported with a controlled ratio of components that possess robust room-temperature ferromagnetism. The 2D MHs consist of Cr2 O3 flakes with embedded CrN subdomains and the CrN:Cr2 O3 ratio can be tuned from 0% to 100% during growth. By changing the CrN:Cr2 O3 ratio, the ferromagnetism of the MHs (e.g., saturation magnetization, coercive field), which originates from the interfacial coupling between Cr2 O3 and CrN, can be controlled. Importantly, the obtained Cr2 O3 -CrN MHs are stable in air at elevated temperatures and have robust ferromagnetism with Curie temperature >400 K. This work presents a facile method for fabricating 2D MHs with tunable magnetism which will benefit high-temperature spintronics.

Resolidified Chalcogen-Assisted Growth of Bilayer Semiconductors with Controlled Stacking Orders.

Bilayer semiconductors have attracted much attention due to their stacking-order-dependent properties. However, as both 3R- and 2H-stacking are energetically stable at high temperatures, most of the high-temperature grown bilayer materials have random 3R- or 2H-stacking orders, leading to non-uniformity in optical and electrical properties. Here, a chemical vapor deposition method is developed to grow bilayer semiconductors with controlled stacking order by modulating the resolidified chalcogen precursors supply kinetics. Taking tungsten disulfide (WS2 ) as an example, pure 3R-stacking (100%) and 2H-stacking dominated (87.6%) bilayer WS2 are grown by using this method and both show high structural and optical quality and good uniformity. Importantly, the bilayer 3R-stacking WS2 shows higher field effect mobility than 2H-stacking samples, due to the difference in stacking order-dependent surface potentials. This method is universal for growing other bilayer semiconductors with controlled stacking orders including molybdenum disulfide and tungsten diselenide, paving the way to exploit stacking-order-dependent properties of these family of emerging bilayer materials.

A weakly supervised deep learning model integrating noncontrasted computed tomography images and clinical factors facilitates haemorrhagic transformation prediction after intravenous thrombolysis in acute ischaemic stroke patients.

BACKGROUND: Haemorrhage transformation (HT) is a serious complication of intravenous thrombolysis (IVT) in acute ischaemic stroke (AIS). Accurate and timely prediction of the risk of HT before IVT may change the treatment decision and improve clinical prognosis. We aimed to develop a deep learning method for predicting HT after IVT for AIS using noncontrast computed tomography (NCCT) images. METHODS: We retrospectively collected data from 828 AIS patients undergoing recombinant tissue plasminogen activator (rt-PA) treatment within a 4.5-h time window (n = 665) or of undergoing urokinase treatment within a 6-h time window (n = 163) and divided them into the HT group (n = 69) and non-HT group (n = 759). HT was defined based on the criteria of the European Cooperative Acute Stroke Study-II trial. To address the problems of indiscernible features and imbalanced data, a weakly supervised deep learning (WSDL) model for HT prediction was constructed based on multiple instance learning and active learning using admission NCCT images and clinical information in addition to conventional deep learning models. Threefold cross-validation and transfer learning were performed to confirm the robustness of the network. Of note, the predictive value of the commonly used scales in clinics associated with NCCT images (i.e., the HAT and SEDAN score) was also analysed and compared to measure the feasibility of our proposed DL algorithms. RESULTS: Compared to the conventional DL and ML models, the WSDL model had the highest AUC of 0.799 (95% CI 0.712-0.883). Significant differences were observed between the WSDL model and five ML models (P < 0.05). The prediction performance of the WSDL model outperforms the HAT and SEDAN scores at the optimal operating point (threshold = 1.5). Further subgroup analysis showed that the WSDL model performed better for symptomatic intracranial haemorrhage (AUC = 0.833, F1 score = 0.909). CONCLUSIONS: Our WSDL model based on NCCT images had relatively good performance for predicting HT in AIS and may be suitable for assisting in clinical treatment decision-making.

Association of dietary patterns and sarcopenia in the elderly population: a cross-sectional study.

Background: Sarcopenia, defined as the loss of muscle mass and strength, has been associated with increased hospitalization and mortality. Dietary pattern analysis is a whole diet approach which in this study was used to investigate the relationship between diet and sarcopenia. This study aims to estimate the prevalence of sarcopenia and explore possible factors associated with it among a large population in Beijing, China. Methods: A cross-sectional study with 1,059 participants aged more than 50 years was performed. Sarcopenia was defined based on the guidelines of the Asian Working Group for Sarcopenia. The total score of the MNA-SF questionnaire was used to analyse nutrition status. The baseline demographic information, diet structure and eating habits were collected by clinicians trained in questionnaire data collection and anthropometric and bioimpedance measurements. Results: The overall prevalence of sarcopenia was 8.8% and increased with age: 5%, 5.8%, 10.3% and 26.2% in the 50-59, 60-69, 70-79, and ≥80 years groups, respectively. Marital status (with or without a spouse) was not an independent factor associated with sarcopenia adjusted by age and sex. However, nutritional risk or malnutrition, vegetable diet, advanced age and spicy eating habits were risk factors for sarcopenia. Meanwhile, daily fruit, dairy and nut consumption were protective factors against sarcopenia adjusted by age, sex, income status and spouse status. Conclusion: Although further studies are required to explore the association between healthy dietary patterns and the risk of sarcopenia, the present study provides basic data for identifying correlates of sarcopenia in elderly Chinese individual.

Boost immunizations with NA-derived peptide conjugates achieve induction of NA inhibition antibodies and heterologous influenza protections.

Neuraminidase is suggested as an important component for developing a universal influenza vaccine. Targeted induction of neuraminidase-specific broadly protective antibodies by vaccinations is challenging. To overcome this, we rationally select the highly conserved peptides from the consensus amino acid sequence of the globular head domains of neuraminidase. Inspired by the B cell receptor evolution process, a reliable sequential immunization regimen is designed to result in immuno-focusing by steering bulk immune responses to a selected region where broadly protective B lymphocyte epitopes reside. After priming neuraminidase protein-specific antibody responses in C57BL/6 or BALB/c inbred mice strains by immunization or pre-infection, boost immunizations with certain neuraminidase-derived peptide-keyhole limpet hemocyanin conjugates significantly strengthened serum neuraminidase inhibition activities and cross-protections. Overall, this study provides proof of concept for a peptide-based sequential immunization strategy for achieving targeted induction of cross-protective antibody response, which provides references for designing universal vaccines against other highly variable pathogens.

Characteristics of intestinal microbiota in infants with late-onset breast milk jaundice.

Introduction: In this paper, microbiota analysis was determined to analyze the structure and difference of intestinal microbiota between LBMJ (late-onset breast milk jaundice) infants and healthy individuals. Methods: We collected fresh fecal samples from 13 infants with LBMJ and 13 healthy individuals, then determined the intestinal microbiota by 16 s rRNA sequencing. The differences of microbiota structure, diversity and functional characteristics between the two groups were analyzed, and the correlation between dominant genus and TcB (transcutaneous bilirubin) value was calculated. Results: In this study, there were no significant differences in maternal demographic characteristics, neonatal status and macronutrients in breast milk between the two groups (p > 0.05). There are differences in the structure of intestinal microbiota between LBMJ and the control group. At the genus level, the relative abundance of Klebsiella in the case group is high (p < 0.05). At the same time, correlation analysis indicates that the abundance of Klebsiella is positively correlated with TcB value. The intestinal microbiota richness and diversity (Alpha diversity and Beta diversity) of the two groups were significantly different (p < 0.05). LEfSe analysis showed that 25 genera including Klebsiella was significantly enriched in the LBMJ infants, and the other 17 species are enriched in the control group. Functional prediction analysis indicated that 42 metabolic pathways may be related to the occurrence of LBMJ. Conclusion: In conclusion, characteristic changes are seen in intestinal microbiota compositions between LBMJ infants and the healthy controls. Klebsiella is closely associated with the severity of the disease, which may be due to enhanced ß-glucuronidase activity.

Theoretical Analysis and Verification on Plastic Deformation Behavior of Rocket Nozzle Using a Novel Tube Upsetting-Bulging Method.

The rocket nozzle is one of the core components to ensure the safe flight of rockets. To overcome the problems of multi-step forming, the occurrence of defects, and severe plastic deformation in traditional technology, a novel forming method named tube upsetting-bulging (TUBG) is put forward. With the support of internal pressure, a tube is deformed with an upsetting and bulging process at the same time. The tube is thickened at the small end and thinned at the large end. A nozzle with sharply varying diameters can be obtained. A theoretical model of TUBG that considers wrinkles and rupture is built. The influence factors of internal pressure during TUBG are discussed. Experiments and simulation works are conducted to analyze the plastic deformation process of TUBG. Results show that mechanical properties and geometrical parameters have an obvious influence on critical internal pressure. The proposed theoretical model can be used to predict a forming zone without wrinkles, rupture, and severe strain values. A well-formed nozzle can be obtained using the predicted forming zone, which verifies the correctness of the theoretical analysis. It can be found that TUBG is a novel potential method to fabricate rocket nozzles with high efficiency and quality without defects.

Corrigendum: The effects of three weight management methods on body composition and serum lipids of overweight and obese people.

[This corrects the article DOI: 10.3389/fnut.2022.1073576.].

Genome-Wide Identification of Trehalose-6-phosphate Synthase (TPS) Gene Family Reveals the Potential Role in Carbohydrate Metabolism in Peach.

Trehalose-6-phosphate synthase (TPS) is essential for plant growth and development, linking trehalose-6-phosphate (T6P) to carbon metabolism. However, little is known about the TPS gene family in peaches and their potential roles in regulating carbohydrates in peach fruit. In this study, nine TPS genes were identified in the peach genome and named according to the homologous genes in Arabidopsis. Phylogenetic analysis showed that three subfamilies were identified, including TPSI, TPSII-1, and TPSII-2, which were also consistent with gene structure analysis. Considerable cis-elements were enriched in the promoters, including plant hormone-related elements. Tissue-specific analysis showed that these TPS genes were mainly expressed in leaves, stems, and fruit, showing different expression patterns for each gene. In addition, during fruit development, the content of trehalose-6-phosphate (T6P) was positively correlated with the expression of PpTPS7a and negatively with sucrose non-fermenting-1-related kinase 1 (SnRK1) activity. Transient overexpression and silencing of PpTPS7a in peach fruit validated its function in regulating T6P content and SnRK1 activity.

The effects of three weight management methods on body composition and serum lipids of overweight and obese people.

Introduction: Obesity has become a major health problem worldwide. Diet management is an important means of weight loss. The aim of this study was to explore the improvement effect of a calorie-restricted diet (CRD), 5 + 2 intermittent fasting (5 + 2 IF), and high protein diet (HPD) on weight composition and serum lipid level of overweight and obese people in a short period (3 months). Methods: Fifty-three participants aged 18-60 years and with body mass index (BMI) ranging from 24 to 35 kg/m2 were screened for inclusion and exclusion criteria and were randomly divided into three groups, i.e., CRD, 5 + 2 IF, and HPD. Basic information, body composition, and venous blood samples were collected at baseline and after 3 months of intervention. Body composition was measured using a body composition analyzer (SK-V9), and serum lipids were assayed using the Roche Cobas e702 automatic biochemistry analysis system. The generalized estimating equation (GEE) was used to analyze and compare the repeated measurements of body composition and levels of serum lipids. Results: The results showed that total weight, BMI, body fat mass, muscle mass, visceral fat index, and waist and hip circumferences had significantly decreased in all three groups after 3 months of intervention, and the average weight loss was 3.3 ± 1.14, 4.12 ± 0.05, and 2.62 ± 0.13 kg in CRD, 5 + 2 IF, and HPD groups, respectively. The results of the GEE model indicated that compared with the CRD group, the 5 + 2 IF group showed a more significant decrease in weight (ß = -0.272, P < 0.001), BMI (ß = -0.091, P < 0.001), body fat mass (ß = -0.172, P < 0.001), muscle (ß = -0.043, P < 0.001), and visceral fat index (ß = -0.019, P < 0.001), however, HPD has more advantages in visceral fat index loss (ß = -0.011, P < 0.001) and lean body mass preserve (ß = 0.229, P < 0.001). Conclusion: Our findings showed that the 5 + 2 IF may be more effective in reducing total weight and body fat, and HPD may be more helpful in preventing lean body mass loss during a short-term weight loss intervention.

Dual-metal precursors for the universal growth of non-layered 2D transition metal chalcogenides with ordered cation vacancies.

Two-dimensional (2D) transition metal chalcogenides (TMCs) are promising for nanoelectronics and energy applications. Among them, the emerging non-layered TMCs are unique due to their unsaturated dangling bonds on the surface and strong intralayer and interlayer bonding. However, the synthesis of non-layered 2D TMCs is challenging and this has made it difficult to study their structures and properties at thin thickness limit. Here, we develop a universal dual-metal precursors method to grow non-layered TMCs in which a mixture of a metal and its chloride serves as the metal source. Taking hexagonal Fe1-xS as an example, the thickness of the Fe1-xS flakes is down to 3 nm with a lateral size of over 100 µm. Importantly, we find ordered cation Fe vacancies in Fe1-xS, which is distinct from layered TMCs like MoS2 where anion vacancies are commonly observed. Low-temperature transport measurements and theoretical calculations show that 2D Fe1-xS is a stable semiconductor with a narrow bandgap of ∼60 meV. In addition to Fe1-xS, the method is universal in growing various non-layered 2D TMCs containing ordered cation vacancies, including Fe1-xSe, Co1-xS, Cr1-xS, and V1-xS. This work paves the way to grow and exploit properties of non-layered materials at 2D thickness limit.

Negative results of bronchoalveolar lavage fluid metagenomic next-generation sequencing in critically ill patients.

Objective: Reports on negative results of metagenomic next-generation sequencing (mNGS) are scarce. We aimed to explore the diagnostic value of negative results in bronchoalveolar lavage fluid (BALF) mNGS and how to deal with the negative results in patients with severe respiratory disease. Methods: A retrospective analysis was performed on patients suspected severe community-acquired pneumonia who were admitted to the respiratory intensive care unit of the First Affiliated Hospital of Zhengzhou University from January 2020 to December 2021. According to the final diagnosis as the reference standard, the negative results of mNGS were divided into a true negative group and a false negative group. For enrolled patients, we recorded their demographic data, imaging results, laboratory results, therapeutic processes, and prognoses. Results: A total of 21 patients were enrolled in this study, including 16 true negative patients and 5 false negative patients. In the true negative group, interstitial lung diseases were the most and neoplastic diseases were following. In addition to mNGS, 9 patients underwent pathological examination, 7 patients were finally diagnosed by medical history, autoantibodies, and point-of-care (POC) ultrasound. 14 patients eventually discontinued antibiotics, 2 patients underwent antibiotic de-escalation, the average interval time of treatment adjustment was 3.56 ± 2.00 days. In the false negative group, the leading missed pathogen was fungi, followed by tuberculosis bacilli. In contrast to 2 patients underwent pathological examination, 3 patients were confirmed by routine microbiological tests. Conclusions: Negative results of BALF mNGS can help to rule out infection, but missed diagnoses may also exist. It should be re-evaluated with other clinical informations. Pathological examination or repeated mNGS may be viable options when the diagnosis cannot be confirmed.

Effect of Epidermal Growth Factor in Human Milk and Maternal Diet on Late-Onset Breast Milk Jaundice: A Case-Control Study in Beijing.

Breast milk is crucial in the development of late-onset breast milk jaundice (BMJ), possibly due to the composition of breast milk and the lactating mother's diet. To explore the possible nutritional pathogenesis of late-onset BMJ, we investigated the lactation diet and collected breast milk by following the 42-day postpartum mother−infants pairs in Beijing and a total of 94 pairs were enrolled. The macronutrient content of breast milk was measured, and the epidermal growth factor (EGF) content in breast milk was determined by ELISA. Data on in-hospital and out-of-hospital breastfeeding, infant growth, jaundice-related vaccination, and puerperium diet were collected. The BMJ group received the second dose of hepatitis B vaccine later than the control group, and the difference was statistically significant (p < 0.001). The EGF concentration in breast milk was lower in the BMJ group than in the control group (p = 0.03). When EGF increased by 1 ng/mL, the transcutaneous bilirubin (TcB) value decreased by 0.33 ng/mL and 0.27 ng/mL before and after the adjustment, respectively. A 1 g increase in oil intake led to a 0.38 ng/mL increase in EGF concentration before the adjustment. With a 1 g increase in oil intake, the TcB value decreased by 0.27 ng/mL before the adjustment, and with a 1 g increase in soybean and soybean product intake, the TcB value decreased by 0.34 ng/mL after the adjustment. Collectively, EGF in breast milk may inhibit the occurrence of late-onset BMJ, and the dietary intake of oil in lactating mothers may affect the level of EGF in breast milk, thus affecting the occurrence of late-onset BMJ. Finally, dietary oil intake may be a protective factor for the occurrence of late-onset BMJ by increasing EGF levels in breast milk.

Space-Confined One-Step Growth of 2D MoO2 /MoS2 Vertical Heterostructures for Superior Hydrogen Evolution in Alkaline Electrolytes.

2D material-based heterostructures are constructed by stacking or spicing individual 2D layers to create an interface between them, which have exotic properties. Here, a new strategy for the in situ growth of large numbers of 2D heterostructures on the centimeter-scale substrate is developed. In the method, large numbers of 2D MoS2 , MoO2 , or their heterostructures of MoO2 /MoS2 are controllably grown in the same setup by simply tuning the gap distance between metal precursor and growth substrate, which changes the concentration of metal precursors feed. A lateral force microscope is used first to identify the locations of each material in the heterostructures, which have MoO2 on the top of MoS2 . Noteworthy, the creation of a clean interface between atomic thin MoO2 (metallic) and MoS2 (semiconducting) results in a different electronic structure compared with pure MoO2 and MoS2 . Theoretical calculations show that the charge redistribution at such an interface results in an improved HER performance on the MoO2 /MoS2 heterostructures, showing an overpotential of 60 mV at 10 mA cm-2 and a Tafel slope of 47 mV dec-1 . This work reports a new strategy for the in situ growth of heterostructures on large-scale substrates and provides platforms to exploit their applications.

Tanreqing Injection Attenuates Macrophage Activation and the Inflammatory Response via the lncRNA-SNHG1/HMGB1 Axis in Lipopolysaccharide-Induced Acute Lung Injury.

The etiology of acute lung injury (ALI) is not clear, and the treatment of ALI presents a great challenge. This study aimed to investigate the pathogenesis and potential therapeutic targets of ALI and to define the target gene of Tanreqing (TRQ), which is a traditional Chinese medicine formula composed of five medicines, scutellaria baicalensis, bear bile powder, goat horn powder, honeysuckle and forsythia. Macrophage activation plays a critical role in many pathophysiological processes, such as inflammation. Although the regulation of macrophage activation has been extensively investigated, there is little knowledge of the role of long noncoding RNAs (lncRNAs) in this process. In this study, we found that lncRNA-SNHG1 expression is distinctly regulated in differently activated macrophages in that it is upregulated in LPS. LncRNA-SNHG1 knockdown attenuates LPS-induced M1 macrophage activation. The SNHG1 promoter was bound by NF-κB subunit p65, indicative of SNHG1 being a direct transcriptional target of LPS-induced NF-κB activation. SNHG1 acts as a proinflammatory driver that leads to the production of inflammatory cytokines and the activation of macrophages and cytokine storms by physically interacting with high-mobility group box 1 (HMGB1) in ALI. TRQ inhibited NF-κB signaling activation and binding of NF-κB to the SNHG1 promoter. In conclusion, this study defined TRQ target genes, which can be further elucidated as mechanism(s) of TRQ action, and provides insight into the molecular pathogenesis of ALI. The lncRNA-SNHG1/HMGB1 axis is an ideal therapeutic for ALI treatment.

Highly precise FIR thermometer based on the thermally enhanced upconversion luminescence for temperature feedback photothermal therapy.

A highly precise temperature-feedback photothermal therapy platform in deep tissue is proposed based on all-fiber fluorescence intensity ratio (FIR) thermometry, which provides a promising route to realize real-time temperature monitoring in the minimally invasive treatment of tumors. Highly disordered double perovskite Li2Zn2Mo3O12 (LZMO) phosphors doped with rare earth ions were prepared and intense green upconversion emissions were observed with an ultra-low excitation power. The thermal enhancement of the upconversion luminescence was achieved up to 423 K, which is very beneficial to achieve a good signal-to-noise performance during the temperature-rise period. Superior temperature sensing performance was demonstrated with the maximum absolute sensitivity of 89.9 × 10-4 at 423 K. The strong upconversion emissions and high temperature sensitivity result in a small temperature error (±0.4 K). The integrated bifunctional needle could simultaneously realize temperature measurement and laser heating, which was exhibited in the denaturation of egg white and laser ablation of the porcine liver in vitro.

A method for quantitatively separating the piezoelectric component from the as-received "Piezoelectric" signal.

Polymer-based piezoelectric devices are promising for developing future wearable force sensors, nanogenerators, and implantable electronics, etc. The electric signals generated by them are often assumed as solely coming from the piezoelectric effect. However, triboelectric signals originated from contact electrification between the piezoelectric devices and the contacted objects can produce non-negligible interfacial electron transfer, which is often combined with the piezoelectric signal to give a triboelectric-piezoelectric hybrid output, leading to an exaggerated measured "piezoelectric" signal. Herein, a simple and effective method is proposed for quantitatively identifying and extracting the piezoelectric charge from the hybrid signal. The triboelectric and piezoelectric parts in the hybrid signal generated by a poly(vinylidene fluoride)-based device are clearly differentiated, and their force and charge characteristics in the time domain are identified. This work presents an effective method to elucidate the true piezoelectric performance in practical measurement, which is crucial for evaluating piezoelectric materials fairly and correctly.

Layer-Dependent Raman Spectroscopy and Electronic Applications of Wide-Bandgap 2D Semiconductor ß-ZrNCl.

In recent years, 2D layered semiconductors have received much attention for their potential in next-generation electronics and optoelectronics. Wide-bandgap 2D semiconductors are especially important in the blue and ultraviolet wavelength region, although there are very few 2D materials in this region. Here, monolayer ß-type zirconium nitride chloride (ß-ZrNCl) is isolated for the first time, which is an air-stable layered material with a bandgap of ≈3.0 eV in bulk. Systematical investigation of layer-dependent Raman scattering of ZrNCl from monolayer, bilayer, to bulk reveals a blueshift of its out-of-plane A1g peak at ≈189 cm-1 . Importantly, this A1g peak is absent in the monolayer, suggesting that it is a fingerprint to quickly identify the monolayer and for the thickness determination of 2D ZrNCl. The back gate field-effect transistor based on few-layer ZrNCl shows a high on/off ratio of 108 . These results suggest the potential of 2D ß-ZrNCl for electronic applications.