Extended Response Time Research Articles

Strain-Enhanced Large-Area Monolayer MoS2 Photodetectors.

In this study, we show a direct correlation between the applied mechanical strain and an increase in monolayer MoS2 photoresponsivity. This shows that tensile strain can improve the efficiency of monolayer MoS2 photodetectors. The observed high photocurrent and extended response time in our devices are indicative that devices are predominantly governed by photogating mechanisms, which become more prominent with applied tensile strain. Furthermore, we have demonstrated that a nonencapsulated MoS2 monolayer can be used in strain-based devices for many cycles and extensive periods of time, showing endurance under ambient conditions without loss of functionality. Such robustness emphasizes the potential of MoS2 for further functionalization and utilization of different flexible sensors.

Evaluation of the EasyNAT SARS-CoV-2 assay PCR test for the diagnosis of SARS-CoV-2 infection

Reverse transcription polymerase chain reaction (RT-PCR) tests are commonly utilized in commercial settings but pose challenges due to labor-intensive procedures and extended response times during peak demand. In contrast, real-time fluorescence and isothermal amplification assays using Crossing Priming Amplification (CPA) offer faster genetic material analysis, eliminate subjectivity, and require less manipulation and personnel training.This study aimed to validate the EasyNAT SARS-CoV-2 Assay, a diagnostic kit based on CPA, using oral and nasopharyngeal samples. The EasyNAT kit was compared to the Xpert Xpress SARS-CoV-2 kit, evaluating 873 samples obtained during routine analysis at the Microbiology Laboratory of the Hospital Costa del Sol (Marbella, Spain).The overall sensitivity and specificity for the EasyNAT SARS-CoV-2 Assay were 79.1% (95%CI 74.5–83.7) and 99.5% (95%CI 98.7–100), respectively; with, validity index of 91.9%, positive predictive value of 98.9%, negative predictive value of 88.9%, positive likelihood ratio of 144.5, negative likelihood ratio of 0.21 and a total Youden Index of 0.79. Notably, sensitivity improved in fresh samples (91.4%), along with a high Youden Index (0.91).The EasyNAT SARS-CoV-2 Assay achieved a higher percentage of concordance in positive samples with Xpert Xpress SARS-CoV-2 when analyzing cycle threshold (Ct) intervals below 30 compared to intervals equal or greater than 30, and demons.In conclusion, the EasyNAT SARS-CoV-2 Assay demonstrated high sensitivity and agreement with Xpert Xpress SARS-CoV-2, particularly in fresh samples or when the signal was detected at Ct intervals below 30, indicating higher viral loads. This makes it suitable for rapid screening in various settings, including those with limited access to conventional molecular laboratory setting.

Ultraviolet laser-driven ultra-high transverse voltage in Bi-2201 thin films

The development of high-performance optically induced voltage materials represents a significant challenge within the realm of optical detection. The constraints posed by low induced voltage and extended response times have impeded the practical applicability of optical and thermal radiation detectors. In this investigation, we propose the utilization of superconducting Bi2Sr2CuOy (Bi-2201) as a pulsed laser-induced voltage material, revealing the emergence of notable transverse voltage signals in tilted thin films. A noteworthy peak voltage of 25.12 V is attained upon exposure to ultraviolet pulsed laser (248 nm), with a rapid rise time of merely 60 ns. Furthermore, we establish an empirical equation specific to our laser detection heterostructure, serving as a benchmark for Bi-2201-based laser detection systems. These findings introduce a promising avenue for the expanded practical applications of high-temperature superconductors.

Response time of mixed platoons with traditional and autonomous vehicles in field trials: impact assessment on flow stability and safety

This study investigates the response times of autonomous vehicles (AVs) equipped with adaptive cruise control (ACC) and traditional human-driven vehicles (TVs) in mixed traffic scenarios. The primary objective is to assess how these response times impact the stability and safety of mixed traffic flow, considering the growing prevalence of ACC technology in vehicles worldwide. Utilising a trajectory dataset from OpenACC totalling 3389.70 s, this research introduces a response time estimation framework that combines cross-correlation and partial autocorrelation techniques. The study calibrates Gazis, Herman, and Rothery's (GHR) car-following model to evaluate mixed traffic flow stability and employs a modified time-to-collision (MTTC) surrogate for safety analysis. The study also delves into the influence of vehicle manufacturer diversity on study outcomes. Key findings reveal that the AVs exhibit significantly longer response times, ranging from 1.10–3.20 s, compared to the 0.30–1.90-second range of traditional vehicles (p value < 0.005). These extended response times in AVs contribute to prolonged traffic flow instability and increased traffic conflicts. Moreover, the type of lead vehicle does not significantly affect the response times of either AVs or TVs (p value > 0.005). The study also highlights that vehicle manufacturer diversity does not substantially affect these response times. Additionally, the examination of fitted GHR parameters underscores AVs’ heightened sensitivity to spacing and relative speed, providing insights into AV dynamics in the presence of mixed traffic.

Ultrafast and Broad-Band Graphene Heterojunction Photodetectors with High Gain.

Graphene possesses an exotic band structure that spans a wide range of important technological wavelength regimes for photodetection, all within a single material. Conventional methods aimed at enhancing detection efficiency often suffer from an extended response time when the light is switched off. The task of achieving ultrafast broad-band photodetection with a high gain remains challenging. Here, we propose a devised architecture that combines graphene with a photosensitizer composed of an alternating strip superstructure of WS2-WSe2. Upon illumination, n+-WS2 and p+-WSe2 strips create alternating electron- and hole-conduction channels in graphene, effectively overcoming the tradeoff between the responsivity and switch time. This configuration allows for achieving a responsivity of 1.7 × 107 mA/W, with an extrinsic response time of 3-4 μs. The inclusion of the superstructure booster enables photodetection across a wide range from the near-ultraviolet to mid-infrared regime and offers a distinctive photogating route for high responsivity and fast temporal response in the pursuit of broad-band detection.

Toward a systematic accessibility review process for English language proficiency tests for young learners

In order to make assessments as widely accessible as possible, including to young learners from diverse backgrounds with a wide range of individual needs and characteristics, some developers of standardized tests have resorted to offering accessibility tools (e.g., magnifying/zoom) and accommodations (e.g., extended response time) to test takers. These solutions have some limitations stemming from the fact that they are retroactively applied to tests. One possible avenue to meet the accessibility needs of diverse students is to proactively address accessibility in the development of test content for all learners. In this article, we report on the development and piloting of a systematic accessibility review process intended for all test content at an organization producing large-scale standardized English proficiency tests for elementary and secondary education students in the United States. We describe the theoretical and research foundations related to fairness, accessibility, and universal design that guided our development of the accessibility review process followed by the process used to develop the tool. The application of the accessibility checklist to a kindergarten English language proficiency assessment is described in detail. Finally, we share some considerations for how the accessibility checklist could be used in other assessment development contexts.

Ambulance Response in Eight Minutes or Less: Are Comorbidities a Factor.

A recommended emergency medical services ambulance response time to a medical emergency is within eight minutes for at least 90% of calls. This study aimed to evaluate scene times for rural education and outreach to improve the quality of trauma care. This is a single-center study of Trauma Registry data from July 1, 2016 to February 28, 2022. The inclusion criteria were based upon age (≥18years). A logistic regression was performed to identify predictor variables on the likelihood that an adult trauma patient will experience scene times greater than eight minutes. 19321 patients were included in the analysis; 7233 (37%) experienced an elapsed scene time within eight minutes. This research identified an opportunity to improve rural trauma team response time, which is only reaching 37% of the patient population within eight minutes. Prehospital cardiac arrest and unique pre-existing comorbidities may play a role in extended response times by EMS.

Protrudent electron transfer channels on kaolinite modified iron oxide QDs/N vacancy graphitic carbon nitride driving superior catalytic oxidation

Optimizing electron transfer channels and sufficiently exposing active sites to trigger an efficient Fenton-like reaction are vital for manipulating catalytic properties of water treatment. Herein, Fe2O3 quantum dots were prepared and integrated with composites of g-C3N4 and kaolinite with nitrogen (N) vacancies (FONGK-10) for bisphenol A (BPA) removal in a peroxymonosulfate (PMS)/visible light (Vis) system. X-ray absorption near-edge structures and extended X-ray absorption fine structures demonstrated interface’s combined properties. In particular, the tight interfacial contact and introduction of N vacancies resulted in the formation of effective electron channels, which caused more effective separation of electron–hole pairs and an extended response time of 1.5 × 10−4 s. Furthermore, the introduction of kaolinite reduced the Fe2O3 particle size and accelerated PMS consumption. The k value in FONGK-10/PMS/Vis system was 4.5 times that of the FONGK-10/PMS and 27.5 times that of the FONGK-10/Vis system, and the synergetic system exhibited superior consecutive catalytic performance in a fluidized-bed catalytic unit, degrading ~100% of BPA in 200 min. The exposed electron channels significantly maintained the Fe(III)/Fe(II) stable dynamic cycle, thereby enhancing the activation of PMS and photocatalysis performance.

Active shooter mitigation strategies in small rural churches.

Gun violence in places of worship (POW) has long been an issue and has been addressed repeatedly in the literature. Contextually, most of the research has been pertinent to relatively large POW, situated in an urban setting. However, rural churches have not been addressed, and they appear to have a far less defensive posture, mainly because of their remote location and the extended time required for first responders to arrive, which in turn requires a higher level of independent operation in terms of defense and medical response. Having retained an off-duty officer is a strong deterrent and provides the ability to handle any issues that may arise, including lower violence level events. If retaining an officer is not an option, having a well-trained volunteer armed team and a clear plan of action is vital to surviving such an event. Furthermore, due to the extended response and transport time, it is critical to have proper medical training, such as Stop the Bleed® and cardio-pulmonary resuscitation. This article's focus is not only on response but preparedness, which reinforces the response, as well as prevention and deterrence. An exhaustive best practices review has informed the solutions offered, supplemented by experience and recommendations of a highly experienced physical security expert and a police officer member of a Special Weapons and Tactics (SWAT) team.

Sub-ppb Sensing Level Hydrogen Sulphide at Room Temperature Using Doped Indium Oxide Gas Sensors

Hydrogen sulfide (H2S) is a highly corrosive, harmful, and toxic gas. Whereas 130 ppb is the threshold for maximum safety exposure level. Thus, it has become mandatory to develop highly sensitive sensors operating at room temperature to detect low levels of H2S. Sensors based on electrochemical measurement principles, semiconducting metal oxides or p–n heterojunctions have showed promising results to detect H2S gas. To date, drawbacks have boon reported due to their extended response times, high operating temperatures, limited selectivity to the gas and/or sensitivity to humidity changes. Efforts have been made to develop sensors based on metal oxides operable at room-temperature for H2S detection.Here, we describe novel flexible H2S gas sensors based on optimized composite mixture of indium oxide (In2O3), copper acetate (CuAc), graphite (Gt) and polystyrene (PS). While we employed Gt in sensor’s structure to reduce sensor’s resistance to ~ 0.5 MΩ, we used PS and enhance sensor’s integrity as well as the adhesiveness of the sensing layer on the top of carbon electrodes. Whereas we applied In2O3 as the active material in sensors due to its promising performance to detect ~ 100 ppb gas concentration. We used CuAc as activator when it converts to the form of copper sulfide (CuS) due to its high conductivity (10 S/cm). Hypothetically, upon exposing sensors to the H2S gas, In2O3 converts spontaneously to the metallic form In2S3 (eq.1). Alternately, CuAc plays two critical roles in the sensor composition. First, CuS formation drops sensor’s resistance significantly due its high conductivity (eq.2). At this point, In2S3 and CuS can form a continues metallic layer, thus it increases sensor’s conductivity. Second, CuS may play a similar role as same as noble metals, which can cause the formation the structure of noble-doped metal oxide and ease oxygen molecules adsorption/ionization on sensor’s surface (eq.3,4). This may facilitate oxidizing and/or adsorption H2S on the sensor’s surface (eq.5,6), which consists of releasing electrons to sensors and reduce sensors resistance dramatically. The developed sensors have showed high selectivity toward H2S gas, high sensitivity to H2S concentration of less than 100 ppb, fast detection time less than 60 seconds, and high resistivity to humidity changes. Figure 1

WebIDE Cloud Server Resource Allocation With Task Pre-Scheduling in IoT Application Development

WebIDE is leveraged for IoT application development, which could adapt to the rapid growth of IoT applications and meanwhile facilitate the rapid development. Resource allocation is of vital significance in the WebIDE cloud service system. Existing resource allocation approaches may encounter issues such as unbalanced resource assignments, which could lead to the reduced system resource utilization or extended system response time. Existing methods are typically on the basis of predetermined resource demands for each task, and not applicable to the case that the resource demands are dynamic and unknown. This article predicts the tasks to be performed by the WebIDE cloud service through task pre-scheduling, and then applies the existing resource allocation methods. Firstly, all tasks are classified, based on the execution state, execution operations and WebIDE cloud server resource requirements. Secondly, the grouped tasks are mapped to different system states, with the Markov state transition probability matrix leveraged to model the transition probability between tasks, followed by the prediction model constructed. Finally, integrating task pre-scheduling with ant colony algorithm, WebIDE cloud server resource allocation is carried out. Experiment results show that adding the task prediction model could significantly not only reduce the task response time, but also improve the cloud server resource utilization.

A double standard model for allocating limited emergency medical service vehicle resources ensuring service reliability

This paper introduces a new double standard model (DSM), along with a genetic algorithm (GA), for solving the emergency medical service (EMS) vehicle allocation problem that ensures acceptable service reliability with limited vehicle resources. Without loss of generality, the model is formulated to address emergency services to human injuries caused by vehicle crashes at intersections within an urban street network. The EMS fleet consists of basic life support (BLS) and advanced life support (ALS) vehicles suited for treating crashes with different severity levels within primary and secondary service coverage standards corresponding to extended response times. The model ensures that all demand sites are covered by at least one EMS vehicle within the secondary standard and a portion of which also meets the service reliability requirement. In addition, a portion of demand sites can be covered by at least one of each type of EMS vehicles within the primary standard. Meanwhile, it aims to achieve maximized coverage of demand sites within the primary standard that complies with the required service reliability. A computational experiment is conducted using 2004–2010 data on top two hundred high crash intersections in the city of Chicago as demand sites for model application. With an EMS fleet size of 15 BLS and 60 ALS ambulances maintained by the Chicago Fire Department, at best 92.4–95.5% of demand could be covered within the secondary standard at 90% of service reliability; and 65.5–68.4% of high severity demand and 50.2–54.5 low severity demand could be covered within the primary standard at 90% of service reliability. The model can help optimize EMS vehicle allocation in urban areas.

Synthesis and Properties of 1-(3,5-dimethyl-4-isoxazole)-2-(2-methyl-(5-ethynyl)-3-thienyl)perfluorocyclopentene

A new photochromic diarylethene of 1-(3,5-dimethyl-4-isoxazole)-2- (2-methyl-(5-ethynyl)-3-thienyl) perfluorocyclopentene (1o) was synthesized. Its photochromic and fluorescence properties were investigated systematically. Upon irradiation with UV light with the extended response time, the diarylethene underwent a ring opening reaction to produce closed forms and color change in solution. The results showed the compound exhibited good photochromism in hexane solution. The kinetic experiments showed that the cyclization and cycloreversion processes were zeroth and first order reaction, respectively. Moreover, diarylethene1oalso exhibited obviously fluorescence switches along with the photochromism.

Synthesis and Properties of [1-(3,5-dimethyl-4-iodoisoxazole)-2-(2-methyl-(5-ethynyl)trimethylsilane-3-thienyl)perfluorocyclopentene

A photochromic diarylethene of [1-(3,5-dimethyl-4-iodoisoxazole)-2-(2-methyl-(5-ethynyl) trimethylsilane-3-thienyl) perfluorocyclopentene (1o) was synthesized and characterized. Its properties, including photochromic behavior and fluorescent properties have been investigated. Upon irradiation with UV light with the extended response time, the diarylethene underwent a ring opening reaction to produce closed forms and color change in solution. The results showed the compound exhibited good photochromism in acetonitrile solution. The kinetic experiments showed that the cyclization and cycloreversion processes were zeroth and first order reaction, respectively. Moreover, diarylethene1oalso exhibited obviously fluorescence switches along with the photochromism.

Synthesis, Photochromism and Fluorescent Switch of 1-(2-methyl-1-benzofuran-3-yl)-2-(2-methyl-5-(4-benzylamine)-3-thienyl)) perfluorocyclopentene

A photochromic diarylethene of 1-(2-methyl-1-benzofuran-3-yl)-2-(2-methyl-5-(4-benzylamine)-3-thienyl)) perfluorocyclopentene was synthesized and characterized. Upon irradiation with UV light with the extended response time, the diarylethene underwent a ring opening reaction to produce opened forms and color change both in solution and in a PMMA amorphous film. Its properties, including photochromic behavior and fluorescent properties have been investigated. The results showed the compound exhibited good photochromism in acetonitrile solution and in PMMA amorphous film.

Monitoring of hydrogen sulfide via substrate-integrated hollow waveguide mid-infrared sensors in real-time

Hydrogen sulfide is a highly corrosive, harmful, and toxic gas produced under anaerobic conditions within industrial processes or in natural environments, and plays an important role in the sulfur cycle. According to the U.S. Occupational Safety and Health Administration (OSHA), the permissible exposure limit (during 8 hours) is 10 ppm. Concentrations of 20 ppm are the threshold for critical health issues. In workplace environments with human subjects frequently exposed to H2S, e.g., during petroleum extraction and refining, real-time monitoring of exposure levels is mandatory. Sensors based on electrochemical measurement principles, semiconducting metal-oxides, taking advantage of their optical properties, have been described for H2S monitoring. However, extended response times, limited selectivity, and bulkiness of the instrumentation are common disadvantages of the sensing techniques reported to date. Here, we describe for the first time usage of a new generation of compact gas cells, i.e., so-called substrate-integrated hollow waveguides (iHWGs), combined with a compact Fourier transform infrared (FTIR) spectrometer for advanced gas sensing of H2S. The principle of detection is based on the immediate UV-assisted conversion of the rather weak IR-absorber H2S into much more pronounced and distinctively responding SO2. A calibration was established in the range of 10-100 ppm with a limit of detection (LOD) at 3 ppm, which is suitable for occupational health monitoring purposes. The developed sensing scheme provides an analytical response time of less than 60 seconds. Considering the substantial potential for miniaturization using e.g., a dedicated quantum cascade laser (QCL) in lieu of the FTIR spectrometer, the developed sensing approach may be evolved into a hand-held instrument, which may be tailored to a variety of applications ranging from environmental monitoring to workplace safety surveillance, process analysis and clinical diagnostics, e.g., breath analysis.

S87 The effect of on patient comfort and neural respiratory drive (NRD) of ventilator trigger delay during non-invasive ventilation (NIV)

IntroductionOptimising patient-ventilator interaction (PVI) has been shown to enhance patient comfort and respiratory muscle unloading. A major cause of poor PVI is ventilator trigger delay, defined as an extended response...

Demand response from the non-domestic sector: Early UK experiences and future opportunities

Demand response is believed by some to become a major contributor towards system balancing in future electricity networks. Shifting or reducing demand at critical moments can reduce the need for generation capacity, help with the integration of renewables, support more efficient system operation and thereby potentially lead to cost and carbon reductions for the entire energy system.In this paper we review the nature of the response resource of consumers from different non-domestic sectors in the UK, based on extensive half hourly demand profiles and observed demand responses. We further explore the potential to increase the demand response capacity through changes in the regulatory and market environment.The analysis suggests that present demand response measures tend to stimulate stand-by generation capacity in preference to load shifting and we propose that extended response times may favour load based demand response, especially in sectors with significant thermal loads.

To resuscitate or not? The emergency physician's decision in the prehospital setting

To identify factors affecting the decision to withhold resuscitative attempts or to terminate cardiopulmonary resuscitation (CPR) in the prehospital setting. In a physician-based emergency medical system (EMS) standardised interviews with the emergency physicians were performed within 24 hours after unsuccessful or withheld CPR-efforts. Over a period of one year 170 prehospital cardiac arrests were evaluated. 47 patients (28 %) were declared dead on arrival by the emergency physician. The decision to withhold CPR was based on obvious clinical signs of death (32 patients) or the diagnosis of cardiac arrest due to severe trauma (8 patients). In 4 cases the terminal state of a fatal illness was the emergency physician's criterion not to initiate resuscitative efforts. In 3 patients an extended response time (more than 10 minutes) was mentioned, in combination with a primary rhythm of either asystole or electromechanical dissociation and additional information given by the family doctor. In 123 patients CPR was attempted. In 72 cases (59 %) resuscitative efforts were terminated as no return and stabilisation of spontaneous circulation was achieved. In 58 patients the decision to stop CPR was based on the evidence of cardiac death. Additional criteria for the termination of the resuscitation attempt were the duration of CPR, an extended response time, pre-existing diseases, age, pupillary status, missing brain stem reflexes, the reason of cardiac arrest, information given by the family or the family doctor and secondarily evolving signs of death. In 14 patients the emergency physicians reported that their decision to terminate CPR was primarily based on these co-factors, the evidence of cardiac death was not explicitly mentioned in these cases. In the pre-hospital setting the decision to withhold or to withdraw CPR is mostly based on reliable criteria such as obvious clinical signs of death, fatal trauma or evidence of cardiac death. Nevertheless, in a small but considerable number of cases exceptions to this rule are made by emergency physicians.

Determination of 4-aminophenol using the quartz crystal microbalance sensor.

In this paper we report a method for the determination of 4-aminophenol (4-AP) in solution using a quartz crystal microbalance (QCM) sensor. 4-AP reacts with (para-unsubstituted) phenols to form hydrophobic indophenol dye species that precipitate out and adsorb to the surface of the crystal to produce a shift in the crystal resonant frequency. This frequency change, due to in-situ indophenol mass adsorption, can be related to the initial 4-AP concentration. A range of phenols (namely o-cresol, 1-naphthol, resorcinol, catechol and 8-hydroxyquinoline) and their reaction with 4-AP were tested. Ammonium persulfate (APS) and potassium periodate were used as initiators to improve the speed of the reaction and the rate of formation of the precipitate. APS elicited improved signal in terms of response times and frequency shifts compared with KIO4. Of the phenols studied, resorcinol gave the best response time of 6 min for 4-AP determination. The reaction of resorcinol with 4-AP gave extended response times and signal size with decreasing concentration of 4-AP (in the range 2-5 mM).