Antimony-Platinum Modulated Contact Enabling Majority Carrier Polarity Selection on a Monolayer Tungsten Diselenide Channel.

We develop a novel metal contact approach using an antimony (Sb)-platinum (Pt) bilayer to mitigate Fermi-level pinning in 2D transition metal dichalcogenide channels. This strategy allows for control over the transport polarity in monolayer WSe2 devices. By adjustment of the Sb interfacial layer thickness from 10 to 30 nm, the effective work function of the contact/WSe2 interface can be tuned from 4.42 eV (p-type) to 4.19 eV (n-type), enabling selectable n-/p-FET operation in enhancement mode. The shift in effective work function is linked to Sb-Se bond formation and an emerging n-doping effect. This work demonstrates high-performance n- and p-FETs with a single WSe2 channel through Sb-Pt contact modulation. After oxide encapsulation, the maximum current density at |VD| = 1 V reaches 170 µA/µm for p-FET and 165 µA/µm for n-FET. This approach shows promise for cost-effective CMOS transistor applications using a single channel material and metal contact scheme.

Clinical Approach to Massive Hemoptysis: Perioperative Focus on Causes and Management.

Massive hemoptysis is a time critical airway emergency in the perioperative setting, with an associated mortality exceeding 50%. Causes of hemoptysis in the perioperative setting include procedural complication, coagulopathy, malignancy, chronic lung disease, infection, left-sided cardiac disease, pulmonary vascular disease and autoimmune disease. A rapid and coordinated multidisciplinary response is required to secure the airway, isolate the lung, ensure adequate oxygenation and ventilation, identify the underlying cause and initiate specific systemic, bronchoscopic, endovascular, or surgical treatment. This review examines the etiology, pathophysiology, as well as approach to management and interventions in perioperative massive hemoptysis.

Knowledge and thresholds for palliative care and surgery among healthcare providers caring for adults with serious illness.

Introduction: Timely palliative care and surgical interventions improve symptoms, health-related quality of life (HRQoL), and reduce medical cost for seriously ill adults at end of life (EOL). However, there is still poor delivery and underutilization of these palliative services. We hypothesize that the sub-optimal delivery is due to limited understanding among healthcare providers. Methods: A nationwide cross-sectional online survey was conducted among primary and tertiary healthcare providers. The survey assessed challenges faced, palliative education, confidence in managing palliative patients, and knowledge on palliative surgery. Overall palliative care awareness and knowledge was assessed using a 6-point score. Likelihood of considering various palliative interventions at EOL was also determined using a threshold score (higher score = higher threshold). Results: There were 145 healthcare providers who completed the survey (81.9% response rate); majority reported significant challenges in providing various aspects of palliative care: 57% (n = 82) in the provision of emotional support. Sixty-nine percent (n = 97) in managing social issues, and 71% (n = 103) in managing family expectations. Most expressed inadequate palliative care training in both under-graduate and post-graduate training and lack confidence in managing EOL issues. Up to 57% had misconceptions regarding potential benefits, morbidity and mortality after palliative surgery. In general, most providers had high thresholds for Intensive Care Unit admissions and palliative surgery, and were more likely to recommend endoscopic or interventional radiology procedures at EOL. Conclusion: Healthcare providers in Singapore have poor knowledge and misconceptions about palliative care and surgery. Improving awareness and education among those caring for seriously ill adults is essential.

Analgesia efficacy of erector spinae plane block in laparoscopic Abdominal surgeries: A systemic review and meta-analysis.

BACKGROUND: Multimodal analgesia is now widely practised to minimise postoperative opioid consumption while optimising pain control. The aim of this meta-analysis was to assess the analgesic efficacy of erector spinae plane block (ESPB) in patients undergoing laparoscopic abdominal surgeries. This will be determined by perioperative opioid consumption, subjective pain scores and incidences of postoperative nausea and vomiting. METHODS: We systemically searched electronic databases for randomised controlled trials (RCTs) published up to February 2023 comparing ESPB with other adjuvant analgesic techniques in laparoscopic abdominal surgeries. Nine randomised controlled trials encompassing 666 subjects were included in our study. RESULTS: ESPB was shown to reduce postoperative opioid consumption [mean difference (MD) of -5.95mg (95% CI: -8.86 to -3.04; P< 0.0001); I2=89%], intraoperative opioid consumption [mean difference (MD) of -102.4mcg (95% CI: -145.58 to -59.21; P< 0.00001); I2=39%] and incidence of nausea [RR 0.38 (95% CI: 0.25 to 0.60; P< 0.0001); I2=0%] and vomiting [RR 0.32 (95% CI: 0.17 to 0.63; P=0.0009); I2=0%] in laparoscopic abdominal surgeries. Subgroup analysis on laparoscopic colorectal surgeries further showed reduction in postoperative pain scores [mean difference (MD) of -0.68 (95% CI: -0.94 to -0.41); P< 0.00001; I2=0%]. CONCLUSIONS: This study concludes that ESPB is a valuable technique with proven efficacy to potentially promote faster postoperative recovery through optimising pain control while minimising opioid requirements.

Evaluating the carbon footprint of sedation practices in intensive care.

BACKGROUND: Healthcare's carbon footprint contributes to 4.4% of global net emissions and intensive care units (ICUs) are very resource intensive. Existing studies on environmental sustainability in ICUs focused on carbon footprint generated from energy and electricity consumption, use of medical consumables and equipment, but few studies quantified carbon footprint generated from pharmaceuticals used in ICUs. AIM: To evaluate carbon footprint arising from sedation practices in the ICUs. STUDY DESIGN: A pilot, prospective observational study was conducted in two ICUs from 1 August to 22 September 2022 in Singapore General Hospital. Adult patients who were consecutively sedated, intubated and expected to be mechanically ventilated for at least 24 h were included. Total amount of analgesia and sedatives used and wasted in eligible patients were collected. Carbon emission from ICU sedation practices were then quantified using available life cycle assessment data. RESULTS: A total of 31 patients were recruited. Top analgesia and sedative used in both ICUs were fentanyl and propofol, respectively. Carbon footprint from sedative usage and wastage across 7 weeks in both ICUs were 2.206 kg CO2-e and 0.286 g CO2-e, respectively. In total, this equates to driving 15.8 km by car. Proportion of drug wasted ranged from 5.1% to 25.0%, with the top reason for wastage being the drug was no longer clinically indicated. Recommendations to reduce carbon footprint include choosing sedatives with lower carbon emissions where possible and having effective communication among doctors and nurses regarding management plans to minimize unnecessary wastage. CONCLUSION: Our study quantified carbon footprint arising from sedation practices, mainly drug usage and wastage in two ICUs in Singpore General Hospital. RELEVANCE TO CLINICAL PRACTICE: Adopting a holistic approach to environmental sustainability in the ICU, sedation practices also contribute to generating greenhouse gases, albeit small, and can be targeted to reduce unnecessary carbon footprint.

Time to intubation with McGrath ™ videolaryngoscope versus direct laryngoscope in powered air-purifying respirator: a randomised controlled trial

INTRODUCTION@#During the coronavirus disease 2019 (COVID-19) pandemic, multiple guidelines have recommended videolaryngoscope (VL) for tracheal intubation. However, there is no evidence that VL reduces time to tracheal intubation, and this is important for COVID-19 patients with respiratory failure.@*METHODS@#To simulate intubation of COVID-19 patients, we randomly assigned 28 elective surgical patients to be intubated with either McGrath™ MAC VL or direct laryngoscope (DL) by specialist anaesthetists who donned 3M™ Jupiter™ powered air-purifying respirators (PAPR) and N95 masks. The primary outcome was time to intubation.@*RESULTS@#The median time to intubation was 61 s (interquartile range [IQR] 37-63 s) and 41.5 s (IQR 37-56 s) in the VL and DL groups, respectively ( P = 0.35). The closest mean distance between the anaesthetist and patient during intubation was 21.6 ± 4.8 cm and 17.6 ± 5.3 cm in the VL and DL groups, respectively ( P = 0.045). There were no significant differences in the median intubation difficulty scale scores, proportion of successful intubations at the first laryngoscopic attempt and proportion of intubations requiring adjuncts. All the patients underwent successful intubation with no adverse event.@*CONCLUSION@#There was no significant difference in the time to intubation of elective surgical patients with either McGrath™ VL or DL by specialist anaesthetists who donned PAPR and N95 masks. The distance between the anaesthetist and patient was significantly greater with VL. When resources are limited or disrupted during a pandemic, DL could be a viable alternative to VL for specialist anaesthetists.

High-Performance WSe2 Top-Gate Devices with Strong Spacer Doping.

Because of the lack of contact and spacer doping techniques for two-dimensional (2D) transistors, most high-performance 2D devices have been produced with nontypical structures that contain electrical gating in the contact regions. In the present study, we used chloroauric acid (HAuCl4) as a strong p-dopant for WSe2 monolayers used in transistors. The HAuCl4-doped devices exhibited a record-low contact resistance of 0.7 kΩ·µm under a doping concentration of 1.76 × 1013 cm-2. In addition, an extrinsic carrier diffusion phenomenon was discovered in the HAuCl4-WSe2 system. With a suitably designed spacer length for doping, a normally off, high-performance underlap top-gate device can be produced without the application of additional gating in the contact and spacer regions.

OCIF: automatically learning the optimized clinical information fusion method for computer-aided diagnosis tasks.

PURPOSE: In computer-aided diagnosis, the fusion of image features extracted from neural networks and clinical information is crucial to improve diagnostic accuracy. How to integrate low-dimensional clinical information (LDCF) with high-dimensional network features (HDNF) is an urgent problem to be solved. We offer a new network search framework to address this problem, which can provide optimized LDCF fusion and efficient dimensionality reduction in HDNF. METHODS: OCIF innovatively uses Gaussian process optimization to explore the search space for the number of fully connected (FC) layers, the number of neurons in each FC layer, the activation function, the dropout factor, and whether to add clinical information to each FC layer. Moreover, OCIF employs transfer learning to reduce the training parameter space and improve search efficiency. To evaluate the effectiveness of the proposed OCIF, we utilized three popular end-to-end overall survival (OS) time prediction models to predict the three classes. RESULTS: Our experimental results show that applying OCIF to a classical computer-aided diagnosis neural network can improve classification accuracy. Experiments on the 2020 BRATS dataset prove that OCIF achieves satisfactory performance, with an accuracy of 0.684, precision of 0.735, recall of 0.684, and F1-score of 0.675 on the OS time prediction task. CONCLUSION: OCIF effectively and creatively combines clinical information and network features, leveraging both clinical information and image features to enhance the accuracy of the final diagnosis. Our experiments demonstrate that the use of OCIF can significantly improve computer-aided diagnosis accuracy, and the approach has the potential to be extended to other medical classification tasks as well.

A Ratiometric SERS Probe for Imaging the Macrophage Phenotypes in Live Mice with Epilepsy and Brain Tumor.

Macrophage performs multiple functions such as pathogen phagocytosis, antigen presentation, and tissue remodeling by polarizing toward a spectrum of phenotypes. Dynamic imaging of macrophage phenotypes is critical for evaluating disease progression and the therapeutic response of drug candidates. However, current technologies cannot identify macrophage phenotypes in vivo. Herein, a surface-enhanced Raman scattering nanoprobe, AH1, which enables the accurate determination of physiological pH with high sensitivity and tissue penetration depth through ratiometric Raman signals is developed. Due to the phenotype-dependent metabolic reprogramming, AH1 can effectively identify macrophage subpopulations by measuring the acidity levels in phagosomes. After intravenous administration, AH1 not only visualizes the spatial distribution of macrophage phenotypes in brain tumors and epileptic regions of mouse models, but also reveals the repolarization of macrophages in brain lesions after drug intervention. This work provides a new tool for dynamically monitoring the disease-associated immune microenvironment and evaluating the efficacy of immune-therapeutics in vivo.

Pre-operative erector spinae plane block should be considered a viable option for laparoscopic colectomies.

BACKGROUND: The Erector Spinae Plane (ESP) block is a recent development in the field of regional anaesthesia and has been increasingly explored for abdominal surgeries to reduce opioid use and improve pain control. Colorectal cancer is the commonest cancer in multi-ethnic Singapore and requires surgery for curative treatment. ESP is a promising alternative in colorectal surgeries, but few studies have evaluated its efficacy in such surgeries. Therefore, this study aims to evaluate the use of ESP blocks in laparoscopic colorectal surgeries to establish its safety and efficacy in this field. METHODS: A prospective two-armed interventional cohort study comparing T8-T10 ESP blocks with conventional multimodal intravenous analgesia for laparoscopic colectomies was conducted in a single institution in Singapore. The decision for doing an ESP block versus conventional multimodal intravenous analgesia was made by a consensus between the attending surgeon and anesthesiologist. Outcomes measured were total intra-operative opioid consumption, post-operative pain control and patient outcome. Post-operative pain control was measured by pain score, analgesia use, and amount of opioids consumed. Patient outcome was determined by presence of ileus. RESULTS: A total of 146 patients were included, of which 30 patients received an ESP block. Overall, the ESP group had a significantly lower median opioid usage both intra-operatively and post-operatively (p = 0.031). Fewer patients required patient-controlled analgesia and rescue analgesia post-operatively for pain control (p < 0.001) amongst the ESP group. Pain scores were similar and post-operative ileus was absent in both groups. Multivariate analysis found that the ESP block had an independent effect on reducing intra-opioid consumption (p = 0.014). Multivariate analysis of post-operative opioid use and pain scores did not yield statistically significant results. CONCLUSIONS: The ESP block was an effective alternative regional anaesthesia for colorectal surgery that reduced intra-operative and post-operative opioid use while attaining satisfactory pain control.

High-Performance Two-Dimensional Electronics with a Noncontact Remote Doping Method.

Because of the intrinsic low carrier density of monolayer two-dimensional (2D) materials, doping is crucial for the performance of underlap top-gated 2D devices. However, wet etching of a high-k (dielectric constant) dielectric layer is difficult to implement without causing performance deterioration on the devices; therefore, finding a suitable spacer doping technique for 2D devices is indispensable. In this study, we developed a remote doping (RD) method in which defective SiOx can remotely dope the underlying high-k capped 2D regions without directly contacting these materials. This method achieved a doping density as high as 1.4 × 1013 cm-2 without reducing the mobility of the doped materials; after 1 month, the doping concentration remained as high as 1.2 × 1013 cm-2. Defective SiOx can be used to dope most popular 2D transition-metal dichalcogenides. The low-k properties of SiOx render it ideal for spacer doping, which is very attractive from the perspective of circuit operation. In our experiments, MoS2 and WS2 underlap top-gate devices exhibited 10× and 200× increases in their on-currents, respectively, after being doped with SiOx. These results indicate that SiOx doping can be conducted to manufacture high-performance 2D devices.

An unusual case of dengue fever in aneurysmal subarachnoid haemorrhage: diagnosis and management nuances.

BACKGROUND: Dengue fever is highly prevalent in the Asia-Pacific region. Here we present an unusual case of dengue fever in a patient with a ruptured cerebral aneurysm causing subarachnoid (SAH) and intraventricular haemorrhage (IVH) and discuss the implications of dengue-related thrombopathies on the management of SAH and its complications. CASE REPORT: A 56-year-old female with a two-day history of high-grade pyrexia and myalgia presented with sudden-onset drowsiness (presenting Glasgow Coma Scale, GCS: E1V1M4). Imaging revealed extensive SAH and IVH due to a ruptured right middle cerebral artery (MCA) aneurysm, with extensive vasospasm. Blood test revealed thrombocytopenia and a positive NS-1 antigen. She subsequently suffered from two episodes of re-rupture of the aneurysm and elevated intracranial pressure which required a decompressive craniectomy in addition to coilingof the MCA aneurysm. Cerebral perfusion and rheology were maintained with the triple-H therapy. Her GCS improved to E4V1M6, but remained aphasic. DISCUSSIONS: Thrombocytopenia and deranged platelet functions in dengue infection might affect the stability of clot and increase the risk of re-rupture of aneurysm. Immediate securement of the aneurysm was paramount. In cases of severe dengue, plasma leakage could lead to intravascular depletion, and coupled with haemoconcentration and hypotension would further increase the risk for vasospasm.

A cost avoidance study of critical care pharmacists' interventions in a tertiary institution in Singapore.

PURPOSE: The economic impact of critical care pharmacists in the intensive care unit (ICU) setting has not been evaluated in Singapore despite ICUs being high-cost areas. This study was conducted to determine the costs avoided as a result of pharmacists' interventions within multidisciplinary ICU teams in a tertiary hospital in Singapore. METHODS: A single-center, retrospective observational study of accepted pharmacists' interventions was conducted over 6 months in 2020. We adopted a previously published systematic approach to estimate the costs avoided by the healthcare system through pharmacists' interventions. Interventions were independently reviewed by a critical care pharmacist, an intensivist, and an investigator. Cost avoidance was calculated in terms of the additional ICU length of stay that would have resulted had a pharmacist not intervened as well as the direct cost savings achieved. RESULTS: There were 632 medication-related problems (MRPs) associated with the 527 accepted interventions, as some interventions involved multiple MRPs. The most common interventions included correcting inappropriate drug regimens (n = 363; 57%), recommending drug monitoring (n = 65; 10%) and addressing omission of drugs (n = 50; 8%). Over 6 months, gross cost avoidance and net cost avoidance achieved were $186,852 and $140,004, respectively, resulting in a ratio of potential monetary cost avoidance to pharmacist salary of 3.99:1. The top 3 interventions that resulted in the greatest cost avoidance were those that corrected inappropriate drug regimens ($146,870; 79%), avoided adverse drug events (ADEs) ($10,048; 5%), and led to discontinuation of medications without any indication ($7,239; 4%). CONCLUSION: Pharmacists can reduce healthcare expenditure substantially through cost avoidance by performing various interventions in ICUs, particularly in the areas of correcting inappropriate drug regimens, avoiding ADEs, and discontinuing unnecessary medications.

A deep learning model designed for Raman spectroscopy with a novel hyperparameter optimization method.

Raman spectroscopy is a spectroscopic technique typically used to determine vibrational modes of molecules and is commonly used in chemistry to provide a structural fingerprint by which molecules can be identified. With the help of deep learning, Raman spectroscopy can be analyzed more efficiently and thus provide more accurate molecular information. However, no general neural network is designed for one-dimensional Raman spectral data so far. Furthermore, different combinations of hyperparameters of neural networks lead to results with significant differences, so the optimization of hyperparameters is a crucial issue in deep learning modeling. In this work, we propose a deep learning model designed for Raman spectral data and a hyperparameter optimization method to achieve its best performance, i.e., a method based on the simulated annealing algorithm to optimize the hyperparameters of the model. The proposed model and optimization method have been fully validated in a glioma Raman spectroscopy dataset. Compared with other published methods including linear regression, support vector regression, long short-term memory, VGG and ResNet, the mean squared error is reduced by 0.1557 while the coefficient determination is increased by 0.1195 on average.

Intelligent SERS Navigation System Guiding Brain Tumor Surgery by Intraoperatively Delineating the Metabolic Acidosis.

Surgeons face challenges in intraoperatively defining margin of brain tumors due to its infiltrative nature. Extracellular acidosis caused by metabolic reprogramming of cancer cells is a reliable marker for tumor infiltrative regions. Although the acidic margin-guided surgery shows promise in improving surgical prognosis, its clinical transition is delayed by having the exogenous probes approved by the drug supervision authority. Here, an intelligent surface-enhanced Raman scattering (SERS) navigation system delineating glioma acidic margins without administration of exogenous probes is reported. With assistance of this system, the metabolites at the tumor cutting edges can be nondestructively transferred within a water droplet to a SERS chip with pH sensitivity. Homemade deep learning model automatically processes the Raman spectra collected from the SERS chip and delineates the pH map of tumor resection bed with increased speed. Acidity correlated cancer cell density and proliferation level are demonstrated in tumor cutting edges of animal models and excised tissues from glioma patients. The overall survival of animal models post the SERS system guided surgery is significantly increased in comparison to the conventional strategy used in clinical practice. This SERS system holds the promise in accelerating clinical transition of acidic margin-guided surgery for solid tumors with infiltrative nature.

Time to intubation with McGrath™ videolaryngoscope versus direct laryngoscope in powered air-purifying respirator: a randomised controlled trial.

INTRODUCTION: During the COVID-19 pandemic, multiple guidelines have recommended the videolaryngoscope for tracheal intubation. However, there is no evidence that videolaryngoscope reduces time to tracheal intubation, which is important for COVID-19 patients with respiratory failure. METHODS: To simulate intubation of COVID-19 patients, we randomised 28 elective surgical patients to be intubated with either the McGrath™ MAC videolaryngoscope or the direct laryngoscope by specialist anaesthetists donning 3M™ Jupiter™ powered air-purifying respirators (PAPR) and N95 masks. Primary outcome was time to intubation. RESULTS: The median (IQR) times to intubation were 61s (37-63 s) and 41.5s (37-56 s) in the videolaryngoscope and direct laryngoscope groups respectively (p = 0.35). The closest mean (SD) distances between the anaesthetist and the patient during intubation were 21.6 cm (4.8 cm) and 17.6 cm (5.3 cm) in the videolaryngoscope and direct laryngoscope groups, respectively (p = 0.045). There were no significant differences in the median intubation difficulty scale scores, proportion of successful intubation at first laryngoscopic attempt and proportion of intubations requiring adjuncts. Intubations for all the patients were successful with no adverse event. CONCLUSION: There was no significant difference in the time to intubation by specialist anaesthetists who were donned in PAPR and N95 masks on elective surgical patients with either the McGrath™ videolaryngoscope or direct laryngoscope. The distance between the anaesthetist and patient was significantly further with the videolaryngoscope. The direct laryngoscope could be an equal alternative to videolaryngoscope for specialist anaesthetists when resources are limited or disrupted due to the pandemic.

Automatic Detection of Gastric Wall Structure Based on Oral Contrast-Enhanced Ultrasound and Its Application on Tumor Screening.

Gastric cancer is the second most lethal type of malignant tumor in the world. Early diagnosis of gastric cancer can reduce the transformation to advanced cancer and improve the early treatment rate. As a cheap, real-time, non-invasive examination method, oral contrast-enhanced ultrasonography (OCUS) is a more acceptable way to diagnose gastric cancer than interventional diagnostic methods such as gastroscopy. In this paper, we proposed a new method for the diagnosis of gastric diseases by automatically analyzing the hierarchical structure of gastric wall in gastric ultrasound images, which is helpful to quantify the diagnosis information of gastric diseases and is a useful attempt for early screening of gastric cancer. We designed a gastric wall detection network based on U-net. On this basis, anisotropic diffusion technology was used to extract the layered structure of the gastric wall. A simple and useful gastric cancer screening model was obtained by calculating and counting the thickness of the five-layer structure of the gastric wall. The experimental results showed that our model can accurately identify the gastric wall, and it was found that the layered parameters of abnormal gastric wall is significantly different from that of normal gastric wall. For the screening of gastric disease, a statistical model based on gastric wall stratification can give a screening accuracy of 95% with AUC of 0.92.

Process-Oriented In Situ Simulation Is a Valuable Tool to Rapidly Ensure Operating Room Preparedness for COVID-19 Outbreak.

STATEMENT: Process-oriented in situ simulation has been gaining widespread acceptance in the evaluation of the safety of new healthcare teams and facilities. In this article, we highlight learning points from our proactive use of in situ simulation as part of plan-do-study-act cycles to ensure operating room facility preparedness for COVID-19 outbreak. We found in situ simulation to be a valuable tool in disease outbreak preparedness, allowing us to ensure proper use of personal protective equipment and protocol adherence, and to identify latent safety threats and novel problems that were not apparent in the initial planning stage. Through this, we could refine our workflow and operating room setup to provide timely surgical interventions for potential COVID-19 patients in our hospital while keeping our staff and patients safe. Running a simulation may be time and resource intensive, but it is a small price to pay if it can help prevent disease spread in an outbreak.