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Abstract Terahertz (THz) emission spectroscopy (TES) has emerged as a highly effective and versatile technique for investigating the photoelectric properties of diverse materials and nonlinear physical processes in the past few decades. Concurrently, research on two-dimensional (2D) materials has experienced substantial growth due to their atomically thin structures, exceptional mechanical and optoelectronic properties, and the potential for applications in flexible electronics, sensing, and nanoelectronics. Specifically, these materials offer advantages such as tunable bandgap, high carrier mobility, wideband optical absorption, and relatively short carrier lifetime. By applying TES to investigate the 2D materials, their interfaces and heterostructures, rich information about the interplay among photons, charges, phonons and spins can be unfolded, which provides fundamental understanding for future applications. Thus it is timely to review the nonlinear processes underlying THz emission in 2D materials including optical rectification, photon-drag, high-order harmonic generation and spin-to-charge conversion, showcasing the rich diversity of the TES employed to unravel the complex nature of these materials. Typical applications based on THz emissions, such as THz lasers, ultrafast imaging and biosensors, are also discussed. Step further, we analyzed the unique advantages of spintronic terahertz emitters and the future technological advancements in the development of new THz generation mechanisms leading to advanced THz sources characterized by wide bandwidth, high power and integration, suitable for industrial and commercial applications. The continuous advancement and integration of TES with the study of 2D materials and heterostructures promise to revolutionize research in different areas, including basic materials physics, novel optoelectronic devices, and chips for post-Moore’s era.

BackgroundThis study aimed to identify which emergency department (ED) factors impact door-to-needle (DTN) time in acute stroke patients eligible for intravenous thrombolysis. The purpose of analyzing emergency department factors is to determine whether any modifiable factors could shorten the time to thrombolytics, thereby increasing the odds of improved clinical outcomes.MethodsThis was a prospective observational quality registry study that included all patients that received alteplase for stroke. These data are our hospital data from the national Get With The Guidelines Registry. The Get With The Guidelines® Stroke Registry is a hospital-based program focused on improving care for patients diagnosed with a stroke. The program has over five million patients, and hospitals can access their own program data. The registry promotes the use of and adherence to scientific treatment guidelines to improve patient outcomes. The time of patient arrival to the ED was captured via the timestamp in the electronic health record. Arriving between Friday 6 p.m. and Monday 6 a.m. was classified as “weekend,” regardless of the time of arrival. Time to CT, time-to-lab, and presence of a dedicated stroke team were also recorded. Emergency medical services (EMS) run sheets were used to verify arrival via ambulance.ResultsForty-nine percent of the cohort presented during the day shift, 24% during the night shift, and 27% on the weekend. A total of 85% were brought by EMS, and 15% of patients were walk-ins. The median DTN time during the day shift was 37 min (IQR 26–51, range 10–117). The median DTN time during the night shift was 59 min (IQR 39–89, range 34–195). When a dedicated stroke team was present, the median DTN time was 36 min, compared to 51 min when they were not present. The median door-to-CT time was 24 min (IQR 18–31 min). On univariate analyses, arriving during the night shift (P < 0.0001), arriving as a walk-in (P = 0.0080), and longer time-to-CT (P < 0.0001) were all associated with longer DTN time. Conversely, the presence of a dedicated stroke team was associated with a significantly shorter DTN time (P < 0.0001).ConclusionFactors that contribute most to a delay in DTN time include arrival during the night shift, lack of a dedicated stroke team, longer time-to-CT read, and arrival as a walk-in. All of these are addressable factors from an operational standpoint and should be considered when performing quality improvement of hospital protocols.

Abstract Background In this paper, the authors review the safety and practicality of elastomeric respirators for protecting themselves and others from the novel coronavirus or COVID-19. They also describe the safe donning and doffing procedures for this protective gear. Main text Due to the shortage of personal protective equipment (PPE), the CDC has recommended ways to conserve disposable N95 masks, including re-use and extended use, and reserving N95 masks for aerosol-generating procedures. However, these were never made to be re-used. Although the modes of transmission of COVID-19 are not fully understood, based on what we know about severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS), droplets and aerosolized droplets contribute to the spread of this virus. More evidence from Wuhan, China, has demonstrated that COVID-19 viral particles are aerosolized and found in higher concentrations in rooms where PPE is being removed. Thus, it is best for all healthcare providers to have full aerosol protection. Conclusion Given the shortage of PPE for aerosols, it is logical to utilize reusable elastomeric respirators with filter efficiency of 95% or higher. A single elastomeric respirator may replace hundreds to thousands of new disposable N95 masks.

Abstract Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) provide clinical benefits over chemotherapy for lung cancer patients with EGFR activating mutations. Despite initial clinical responses, long‐term efficacy is not possible because of acquired resistance to these therapies. We have developed EGFR TKI drug‐tolerant (DT) human lung cancer cell lines as a model for de novo resistance. Mass spectroscopic analysis revealed that the cytochrome P450 protein, CYP51A1 (Lanosterol 14α‐demethylase), which is directly involved with cholesterol synthesis, was significantly upregulated in the DT cells. Total cellular cholesterol, and more specifically, mitochondrial cholesterol, were found to be upregulated in DT cells. We then used the CYP51A1 inhibitor, ketoconazole, to downregulate cholesterol synthesis. In both parental and DT cells, ketoconazole and EGFR TKIs acted synergistically to induce apoptosis and overcome the development of EGFR tolerance. Lastly, this combination therapy was shown to shrink the growth of tumors in an in vivo mouse model of EGFR TKI resistance. Thus, our study demonstrates for the first time that ketoconazole treatment inhibits upregulation of mitochondrial cholesterol and thereby overcomes EGFR‐TKI resistance in lung cancer cells.

As Moore’s law deteriorates, the research and development of new materials system are crucial for transitioning into the post Moore era. Traditional semiconductor materials, such as silicon, have served as the cornerstone of modern technologies for over half a century. This has been due to extensive research and engineering on new techniques to continuously enrich silicon-based materials system and, subsequently, to develop better performed silicon-based devices. Meanwhile, in the emerging post Moore era, layered semiconductor materials, such as transition metal dichalcogenides (TMDs), have garnered considerable research interest due to their unique electronic and optoelectronic properties, which hold great promise for powering the new era of next generation electronics. As a result, techniques for engineering the properties of layered semiconductors have expanded the possibilities of layered semiconductor-based devices. However, there remain significant limitations in the synthesis and engineering of layered semiconductors, impeding the utilization of layered semiconductor-based devices for mass applications. As a practical alternative, heterogeneous integration between layered and traditional semiconductors provides valuable opportunities to combine the distinctive properties of layered semiconductors with well-developed traditional semiconductors materials system. Here, we provide an overview of the comparative coherence between layered and traditional semiconductors, starting with TMDs as the representation of layered semiconductors. We highlight the meaningful opportunities presented by the heterogeneous integration of layered semiconductors with traditional semiconductors, representing an optimal strategy poised to propel the emerging semiconductor research community and chip industry towards unprecedented advancements in the coming decades.

Background: The optimal multimodality therapy for pancreatic ductal adenocarcinoma in the body or tail of the pancreas (PDAC-BT) is unclear. The purpose of this study was to compare overall 5-year survival between patients treated with adjuvant chemotherapy, adjuvant chemoradiation, and surgery alone. Methods: Patients from the National Cancer Database (1998–2012) with resected stage I or II PDAC-BT were included. Overall survival between the three treatment groups was compared using Cox proportional-hazards regression, propensity-score matching, and the Kaplan–Meier method. Results: Of the 700 patients included in the analysis, 189 (27%) were treated with chemotherapy, 226 (32%) were treated with chemoradiation, and 285 (41%) were treated with surgery alone. Chemoradiation was associated with higher survival than surgery alone [adjusted hazard ratio (HR adj ): 0.67; 95% confidence interval (CI): 0.54, 0.84; p = 0.001], but there was no difference between chemotherapy and chemoradiation (HR adj : 0.82; 95% CI: 0.65, 1.05; p = 0.115). In propensity-score matched cohorts, median survival was 24.1 months (95% CI: 20.4, 28.4) with chemotherapy and 25.4 months (95% CI: 22.1, 31.7) with chemoradiation (log-rank p = 0.122). Among patients with positive resection margins, chemoradiation was associated with higher survival compared with chemotherapy (HR adj : 0.54; 95% CI: 0.32, 0.92; p = 0.022). In this subgroup of the propensity-score matched cohorts, median survival was 9.5 months (95% CI: 8.4, 16.0) with chemotherapy and 18.3 months (95% CI: 11.6, 26.3) with chemoradiation (log-rank p = 0.011). Conclusion: In patients with resected pancreatic body or tail adenocarcinoma, adjuvant chemoradiation was associated with higher survival compared with surgery alone. Among patients with positive resection margins, adjuvant chemoradiation was associated with higher survival compared with adjuvant chemotherapy.

The novel coronavirus SARS-CoV-2, initially identified in late 2019 as a small case cluster, has rapidly become a global pandemic. Government restrictions, closure of primary care services, interruption of cancer screening programmes, and fear of contracting the virus have demonstrably led to a reduction in referrals for suspected cancer and delays to treatment across the United Kingdom. A retrospective analysis was carried out on suspected cancer referrals to the maxillofacial service at Aberdeen Royal Infirmary during the 12 months from March 2020, and compared with the 12 months prior. Suspected cancer referrals reduced by 38.6% (p

Summary: Takotsubo cardiomyopathy is an acute stress-induced heart failure syndrome for which the exact pathogenic mechanisms are unclear, and consequently, no specific treatment exists. In an experimental model of stress-induced takotsubo-like cardiomyopathy, the authors describe the temporal course of a chronic inflammatory response post-induction, with an initial early influx of neutrophils into myocardial tissue followed by macrophages that are typical of a proinflammatory M1 phenotype, and a nonsignificant increase in systemic inflammatory cytokines. Post-mortem myocardium from the more complex clinical takotsubo patients share features of the study’s experimental model. These findings suggest modulators of inflammation could be a potential therapeutic option. Key Words: histopathology, inflammation, macrophage, pathophysiology, takotsubo cardiomyopathy