Fast Time Research Articles

Evaluation of a BioFire multiplex PCR panel for detection of joint infections using retrospective and prospectively collected specimens.

The BioFire Joint Infection Panel (JI panel) is a newly FDA-approved multiplex PCR assay for detection of common bone and joint pathogens with 39 targets which include select Gram-positive and Gram-negative bacteria, yeast, and antimicrobial resistance genes. We evaluated the performance of the JI panel in detecting joint infections in our patient population. Sixty-three frozen, residual joint fluid specimens were retrospectively tested using the JI panel. An additional 104 residual joint fluid specimens were de-identified and prospectively tested within 1 week of collection. Results from routine bacterial cultures were used as the reference standard, which included inoculation to agar plates and blood culture bottles. For the frozen specimens, the JI panel showed a positive percent agreement (PPA) of 92.8% and a negative percent agreement (NPA) of 97.1%. PPA was 71.4% and NPA was 94.8% for fresh specimens. A total of 12 discrepancies were observed among the 167 specimens tested. The JI panel demonstrated good overall agreement with routine culture for the detection of joint infections and may improve timely diagnosis when used in conjunction with bacterial culture. However, potential false-positive and false-negative results were observed in both retrospective and prospective testing of specimens.IMPORTANCEThe BioFire JI panel is a new commercially available multiplex PCR assay for detecting common pathogens causing bone and joint infections. The test is performed directly on joint fluids with a fast turnaround time of 1 hour. Our study shows that while the JI panel overall shows good agreement with routine culture, discrepancies were observed in 7% of cases and results should be interpreted with appropriate clinical context.

Hamstring autografts demonstrate either similar or inferior outcomes to quadriceps or bone-patellar tendon-bone autografts in revision anterior cruciate ligament reconstruction: A systematic review of comparative studies.

To evaluate the clinical outcomes in patients undergoing revision anterior cruciate ligament reconstruction (r-ACLR) using hamstring tendon (HT) autografts with those using either quadriceps tendon (QT) or bone-patellar tendon-bone (BPTB) autografts or allografts. Three databases were searched on 8 August 2023. The authors adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and Revised Assessment of Multiple Systematic Reviews (R-AMSTAR) guidelines and the Cochrane Handbook for Systematic Reviews of Interventions. Data on demographics, surgical details, patient-reported outcome measures (PROMs), rates of instability, failure and return to sport (RTS) were extracted. Eleven studies comprising 859 patients were included in this review. Five studies compared HT and QT autografts. One study each reported greater IKDC scores (p = 0.04) and Tegner scores (p = 0.04) in the QT group, while one study each reported higher anterior translation (p = 0.04), rates of positive pivot shift (p = 0.03) and rates of failure (p = 0.03) in the HT group. Six studies compared HT and BPTB autografts with one study each reporting greater Lysholm scores (p = 0.02) and less side-to-side anterior laxity (p < 0.01) in the BPTB group. Two studies compared HT autografts with allografts with only one study reporting a faster time to RTS in the HT group than the allograft group (p < 0.001). All other comparisons were not significant. HT autografts result in either similar or inferior outcomes in r-ACLR when compared to QT or BPTB autograft options. Allografts resulted in similar outcomes to HT autografts apart from greater time to RTS for r-ACLR. Level III.

Preoperative fasting for elective surgery in children

This review investigated preoperative fasting in children who need elective surgical interventions. Fifty publications included in the abstract databases PubMed and elibrary for the period from 2017 to 2023 were reviewed. For the analysis, we used articles on the effect of preoperative fasting on indicators of the cardiovascular system and water and carbohydrate metabolism and assessed the course of the perioperative period depending on the duration of refusal of solid food and liquids before surgery. The article presents historical information that formed the basis for the modern paradigm of refusal of solid food and liquids in the preoperative period, especially the negative consequences of prolonged refusal of food in the preoperative period, indicating the main ones, namely, euglycemic ketosis and ketoacidosis, which are common in children. Hypoglycemia due to food refusal before surgery is rare and is not a serious problem in most patients, except in children in the first year of life. In most cases, it has been demonstrated that the time of preoperative fasting significantly exceeds the recommended intervals and amounts to more than 10 hours, and 75% of patients experience a strong feeling of hunger. Infusion of dextrose solutions has not been found to reduce feelings of hunger and thirst before surgery. An increase in preoperative fasting time is often associated with improper organization of the process (35.1%), an increase in surgical time (34.1%), and surgical plan changes (20.9%). It is noted that the optimal volume of liquid that a child can drink before surgery is 3 ml/kg. Data indicates that preoperative fasting can cause arterial hypotension after induction of anesthesia, at the stage of preparing the surgical field. It has been demonstrated that a residual gastric volume of 1.25 ml/kg is a risk factor for aspiration during the induction of anesthesia. There is currently no convincing evidence of the negative effect of preoperative fasting on treatment outcome; however, clearly, the time to abandon clear liquids before elective surgery in children should be minimal.

Image inpainting algorithm based on double curvature-driven diffusion model with P-Laplace operator.

The method of partial differential equations for image inpainting achieves better repair results and is economically feasible with fast repair time. Addresses the inability of Curvature-Driven Diffusion (CDD) models to repair complex textures or edges when the input image is affected by severe noise or distortion, resulting in discontinuous repair features, blurred detail textures, and an inability to deal with the consistency of global image content, In this paper, we have the CDD model of P-Laplace operator term to image inpainting. In this method, the P-Laplace operator is firstly introduced into the diffusion term of CDD model to regulate the diffusion speed; then the improved CDD model is discretized, and the known information around the broken region is divided into two weighted average iterations to get the inpainting image; finally, the final inpainting image is obtained by weighted averaging the two image inpainting images according to the distancing. Experiments show that the model restoration results in this paper are more rational in terms of texture structure and outperform other models in terms of visualization and objective data. Comparing the inpainting images with 150, 1000 and 100 iterations respectively, Total Variation(TV) model and the CDD model inpainting algorithm always has inpainting traces in details, and TV model can't meet the visual connectivity, but the algorithm in this paper can remove the inpainting traces well, TV model and the CDD model inpainting algorithm always have inpainting traces in details, and TV model can't meet the visual connectivity, but the algorithm in this paper can remove the inpainting traces well. Of the images used for testing, the highest PSNR reached 38.7982, SSIM reached 0.9407, and FSIM reached 0.9781, the algorithm not only inpainting the effect and, but also has fewer iterations.

Macro-micro decomposition for consistent and conservative model order reduction of hyperbolic shallow water moment equations: a study using POD-Galerkin and dynamical low-rank approximation

Geophysical flow simulations using hyperbolic shallow water moment equations require an efficient discretization of a potentially large system of PDEs, the so-called moment system. This calls for tailored model order reduction techniques that allow for efficient and accurate simulations while guaranteeing physical properties like mass conservation. In this paper, we develop the first model reduction for the hyperbolic shallow water moment equations and achieve mass conservation. This is accomplished using a macro-micro decomposition of the model into a macroscopic (conservative) part and a microscopic (non-conservative) part with subsequent model reduction using either POD-Galerkin or dynamical low-rank approximation only on the microscopic (non-conservative) part. Numerical experiments showcase the performance of the new model reduction methods including high accuracy and fast computation times together with guaranteed conservation and consistency properties.

Effects of integrated management on surgical outcomes and mental health of patients following endoscopic submucosal dissection.

Endoscopic submucosal dissection (ESD) is a less invasive local treatment for diseases throughout the gastrointestinal tract. To develop an integrated management protocol and analyze its effects on surgical outcomes and mental health of patients after ESD. The study population consisted of patients undergoing ESD before implementation of integrated management and those undergoing ESD by the same pool of surgeons after implementation of integrated management. The management group exhibited shortened fasting time and length of hospital stay compared to the control group (P < 0.05). The management group exhibited a higher incidence rate of postoperative complications than the control group (3 cases vs 11 cases; P = 0.043). The management group exhibited a lower uncertainty score for disease knowledge compared to the control group 12 h after surgery (P < 0.05). The management group gave more scores on the domains of patient familiarity to the responsible nurses, professional skills of responsible nurses, and general evaluation compared to the control group. The management group had a higher total score of patient satisfaction towards the responsible nurses in term of health care than the control group (P < 0.01). The management group exhibited lower Self-Rating Anxiety Scale and Self-Rating Depression Scale scores compared to the control group 12 h after surgery (P < 0.01). The study demonstrates that integrated management could improve surgical outcomes and mental health of patients undergoing ESD.

Preparation of Multifunctional Hydrogels with In Situ Dual Network Structure and Promotion of Wound Healing.

As an emerging biomedical material, wound dressings play an important therapeutic function in the process of wound healing. It can provide an ideal healing environment while protecting the wound from a complex external environment. A hydrogel wound dressing composed of tilapia skin gelatin (Tsg) and fucoidan (Fuc) was designed in this article to enhance the microenvironment of wound treatment and stimulate wound healing. By mixing horseradish peroxidase (HRP), hydrogen peroxide (H2O2), tilapia skin gelatin-tyramine (Tsg-Tyr), and carboxylated fucoidan-tyramine in agarose (Aga), using the catalytic cross-linking of HRP/H2O2 and the sol-gel transformation of Aga, a novel gelatin-fucoidan (TF) double network hydrogel wound dressing was constructed. The TF hydrogels have a fast and adjustable gelation time, and the addition of Aga further enhances the stability of the hydrogels. Moreover, Tsg and Fuc are coordinated with each other in terms of biological efficacy, and the TF hydrogel demonstrated excellent antioxidant properties and biocompatibility in vitro. Also, in vivo wound healing experiments showed that the TF hydrogel could effectively accelerate wound healing, reduce wound microbial colonization, alleviate inflammation, and promote collagen deposition and angiogenesis. In conclusion, TF hydrogel wound dressings have the potential to replace traditional dressings in wound healing.

Optimization of fast output from SiPM array for pulse shape discrimination techniques at high counting rates

Plastic scintillators with pulse shape discrimination (PSD) capability, when combined with silicon photo-multipliers (SiPMs), enable the development of compact neutron detectors with lower power consumption and insensitivity to magnetic fields. However, the SiPM array has a significantly large pulse width of the output signal, which leads to discrimination difficulties at high counting rates. There are two outputs of a SiPM array: a standard output for energy measurement and a fast output for timing measurement. The pulse width of the standard output signal is in the range of hundreds nanoseconds, while the pulse width of the other one is in the range of tens nanoseconds. Fast output signals have traditionally been considered suitably for fast timing, however utilizing them for PSD has been little explored. In our previous work, we successfully implemented PSD by using fast output signals from a SiPM. Despite the obvious negative overshoot in fast signals, we achieved PSD of fast signals by using longer sampling times. However, this approach was still limited at high counting rates. This study proposes a compensation network for fast output signals, which is composed of a compensation unit consisting of a resistor and a capacitor. This design effectively compensates the overshoot of the fast output and shortens the pulse width from 60 ns to 44 ns. Additionally, it highlights the frequency amplitude differences between the neutron and gamma signals from fast output in the high-frequency component, thus improving the PSD capability of the fast output.

Timing limits of ultrafast cross-luminescence emission in CsZnCl-based crystals for TOF-CT and TOF-PET.

Good timing resolution in medical imaging applications such as TOF-CT or TOF-PET can boost image quality or patient comfort significantly by reducing the influence of background noise. However, the timing resolution of state-of-the-art detectors in CT and PET are limited by their light emission process. Core-valence cross-luminescence is an alternative, but well-known compounds (e.g. BaF2) pose several problems for medical imaging applications, such as their emission wavelength in the deep UV. CsZnCl-based materials show promise to solve this issue, as they provide fast decay times of 1-2 ns and an emission wavelength around 300 nm. In this work, we investigated two CsZnCl-compounds: Cs2ZnCl4 and Cs3ZnCl5. We validated the previously published decay times on a time-correlated single-photon counting setup with 1.786 ± 0.016 ns for Cs2ZnCl4 and 1.034 ± 0.013 ns for Cs3ZnCl5. The setup's high resolution enabled the discovery of an additional prompt emission component with a significant abundance of 98 ± 18 (Cs2ZnCl4) and 86 ± 14 (Cs3ZnCl5) photons/MeV energy deposit. In a PET coincidence experiment, we measured the best coincidence time resolution (CTR) of 62 ps (FWHM) for Cs2ZnCL4 coupled to FBK VUV SiPMs with silicon oil. To assess the CTR for lower energies, we filtered the energy along the Compton continuum and found a deteriorated CTR that seems to be mainly influenced by photon statistics. Furthermore, this study gave us a rough estimate of e.g. 150 ps (FWHM) CTR at 100 keV energy for Cs2ZnCL4. From measurements with high activity of 14 MBq to check for pile-up effects we assume that Cs2ZnCl4 is better suited for high-rate time-of-flight applications than lutetium-based oxides. Simulations demonstrated that the stopping power of Cs2ZnCl4 is lower than for LSO:Ce,Ca, meaning that a high amount of material would be needed for TOF-PET applications. However, the stopping power seems acceptable for applications in TOF-CT. The fast decay time, state-of-the-art CTR in benchtop experiments and high-rate suitability make CsZnCl materials a promising candidate for time-of-flight experiments. We consider especially TOF-CT a suitable application due to its relatively low X-ray energies (~ 100 keV) and the thusly acceptable stopping power of Cs2ZnCl4. Currently, further exploration of the prompt emission and its creation mechanism is planned, as well as investigating the light transport of Cs2ZnCl4 in longer crystals.

Exploring the Benefits of Stroboscopic Technology and Guided Visualization in Teaching Suturing Techniques to Veterinary Medicine Students

Suturing is widely regarded to be a core competency of veterinary education. With curricular requirements expanding, training interventions that improve students’ suturing skills without added time would be valuable. This study evaluated the effects of stroboscopic visual resistance training, a technique using intermittent occlusion of vision, and guided visualization on suturing technique and speed. Students’ anxiety levels were also assessed. Twenty-nine veterinary students with no prior surgical experience were divided into stroboscopic, visualization and control groups. Simple interrupted, simple continuous, and cruciate patterns were taught by an American College of Veterinary Surgeons (ACVS) boarded veterinarian in week 1, and students also took an anxiety test at this time. One-hour-long tutored practice sessions were held for each group in weeks 2, 3, 4 and 6, and assessments were conducted in weeks 5 and 7. Assessments were conducted by a second ACVS boarded veterinarian blinded to group assignments. Students in the stroboscopic training group had faster suturing times compared to students in the control group for the cruciate pattern at week 5 ( p = 0.001) and week 7 ( p = 0.006), and faster times compared to students in the visualization group at week 5 ( p = 0.002). Students in the stroboscopic training group had faster suturing times than the control group ( p = 0.005) for the simple continuous pattern at week 7. No significant differences were observed in anxiety. There was no significant difference in technique scores for any group with any pattern at any time point. Stroboscopic training may result in faster suturing times without deterioration of suturing technique.

Exploring the Benefits of Stroboscopic Technology and Guided Visualization in Teaching Suturing Techniques to Veterinary Medicine Students

Suturing is widely regarded to be a core competency of veterinary education. With curricular requirements expanding, training interventions that improve students’ suturing skills without added time would be valuable. This study evaluated the effects of stroboscopic visual resistance training, a technique using intermittent occlusion of vision, and guided visualization on suturing technique and speed. Students’ anxiety levels were also assessed. Twenty-nine veterinary students with no prior surgical experience were divided into stroboscopic, visualization and control groups. Simple interrupted, simple continuous, and cruciate patterns were taught by an American College of Veterinary Surgeons (ACVS) boarded veterinarian in week 1, and students also took an anxiety test at this time. One-hour-long tutored practice sessions were held for each group in weeks 2, 3, 4 and 6, and assessments were conducted in weeks 5 and 7. Assessments were conducted by a second ACVS boarded veterinarian blinded to group assignments. Students in the stroboscopic training group had faster suturing times compared to students in the control group for the cruciate pattern at week 5 ( p = 0.001) and week 7 ( p = 0.006), and faster times compared to students in the visualization group at week 5 ( p = 0.002). Students in the stroboscopic training group had faster suturing times than the control group ( p = 0.005) for the simple continuous pattern at week 7. No significant differences were observed in anxiety. There was no significant difference in technique scores for any group with any pattern at any time point. Stroboscopic training may result in faster suturing times without deterioration of suturing technique.

Enhanced Recovery After Surgery versus Conventional Care in Cholecystectomy: A Systematic Review and Meta-Analysis.

Objectives: The primary objective of this study was to evaluate the safety and efficacy of the enhanced recovery after surgery (ERAS) protocol in cholecystectomy, comparing it with standard care. Methods: A comprehensive literature search was conducted in December 2023, using globally recognized databases such as PubMed, Embase, and the Cochrane Library. Various parameters were compared using Review Manager software. This study was duly registered with PROSPERO (CRD420223). Results: The meta-analysis included nine studies, encompassing a total of 1920 patients. The findings revealed that the ERAS group, in comparison to traditional care, experienced shorter hospitalization periods (weighted mean difference [WMD]: -1.23, 95% confidence interval [CI]: -1.98 to -0.47; P = .001), lower visual analog scale at 24 hours (WMD: -1.10, 95% CI: -1.30 to -0.90; P < .00001), faster time to first flatus (WMD: -4.48, 95% CI: -4.50 to -4.46; P < .00001), and reduced operative times (WMD: -9.94, 95% CI: -17.88 to -0.96; P = .03). In addition, there was a notable decrease in instances of postoperative nausea and vomiting (odds ratio [OR]: 0.46, 95% CI: 0.28 to 0.74; P = .002). No significant differences were observed in readmission rates, blood loss, postoperative complications, or bile leakage between the two care methods. Conclusions: This study substantiates that the ERAS protocol is an advantageous perioperative care strategy for patients undergoing cholecystectomy. It significantly outperforms traditional care in reducing the length of stay, decreasing the likelihood of postoperative nausea/vomiting, alleviating postoperative pain, and accelerating the time to the first flatus. These findings highlight the effectiveness of ERAS in enhancing patient outcomes in cholecystectomy.

Enhanced Recovery After Surgery versus Conventional Care in Cholecystectomy: A Systematic Review and Meta-Analysis.

Objectives: The primary objective of this study was to evaluate the safety and efficacy of the enhanced recovery after surgery (ERAS) protocol in cholecystectomy, comparing it with standard care. Methods: A comprehensive literature search was conducted in December 2023, using globally recognized databases such as PubMed, Embase, and the Cochrane Library. Various parameters were compared using Review Manager software. This study was duly registered with PROSPERO (CRD420223). Results: The meta-analysis included nine studies, encompassing a total of 1920 patients. The findings revealed that the ERAS group, in comparison to traditional care, experienced shorter hospitalization periods (weighted mean difference [WMD]: -1.23, 95% confidence interval [CI]: -1.98 to -0.47; P = .001), lower visual analog scale at 24 hours (WMD: -1.10, 95% CI: -1.30 to -0.90; P < .00001), faster time to first flatus (WMD: -4.48, 95% CI: -4.50 to -4.46; P < .00001), and reduced operative times (WMD: -9.94, 95% CI: -17.88 to -0.96; P = .03). In addition, there was a notable decrease in instances of postoperative nausea and vomiting (odds ratio [OR]: 0.46, 95% CI: 0.28 to 0.74; P = .002). No significant differences were observed in readmission rates, blood loss, postoperative complications, or bile leakage between the two care methods. Conclusions: This study substantiates that the ERAS protocol is an advantageous perioperative care strategy for patients undergoing cholecystectomy. It significantly outperforms traditional care in reducing the length of stay, decreasing the likelihood of postoperative nausea/vomiting, alleviating postoperative pain, and accelerating the time to the first flatus. These findings highlight the effectiveness of ERAS in enhancing patient outcomes in cholecystectomy.

The Relationship of the Enterprise Resource Planning (ERP) System to Value Engineering and their Role in Reducing Costs

The research aims to clarify the relationship between the enterprise resource planning system and value engineering, and to clarify their impact on reducing costs. Providing enterprise resource planning eliminates its suffering from its dependence on outdated information systems that are not compatible with rapid changes and established standards. It also supports the presence of an effective procedural structure for performing work that removes obstacles and bottlenecks, invests in means of transferring and flowing information, and excludes jobs that do not bring additional benefit to the work in the series of procedures through which the product or service is produced until it finally reaches the customer in the fastest time and with the least amount. Cost while achieving a high level of quality.

Control-oriented multiphysics model of a lithium-ion battery for thermal runaway estimation under operational and abuse conditions

This study proposes a control-oriented multiphysics model for lithium-ion batteries (LIBs) that can estimate electrochemical-thermal responses in real time under normal operation and abuse conditions. The proposed model integrates the simplified electrochemical model, the thermal resistance network, and the adaptive time-stepping method to ensure computational efficiency without sacrificing the accuracy. Specifically, the diffusion equation of the electrochemical model is simplified by addressing Padé approximation. The thermal resistance network estimates 3D temperature distribution through simple matrix multiplication to account for the entropic, ohmic, and chemical reaction during thermal runaway. The adaptive time-stepping method further secures accurate yet fast explicit calculation. Quantitative experimental validation reveals the high accuracy and robustness, and fast inference time of the proposed model to estimate the electrochemical-thermal responses with the average inference time of 0.0047 s per step. The application of the proposed model on the 26650 LFP cell also demonstrates the versatility on various shapes and types of LIBs. The systematic analysis on the 3D temperature distribution in the LIB of interest not only confirms the effectiveness of the internal temperature monitoring but also ensures the virtual sensing capability. The versatility of the proposed model underscores both design- and control- enabling solutions for battery thermal management.

Enhancing Cloud Data Deduplication with Dynamic Chunking and Public Blockchain

The majority of cloud service providers (CSPs) store and remove customer data according to certain principles. The majority of them have designed their cloud platform to have very high levels of consistency, speed, availability, and durability. Their systems are built with these performance characteristics in mind, and the requirement to ensure precise and rapid data deletion must be carefully balanced. In the public blockchain, this paper suggests employing the rapid content-defined Chunking algorithm for data duplication. Acute data is frequently outsourced by individuals and organizations to distant cloud servers since doing so greatly reduces the headache of maintaining infrastructure and software. However, because user data is transmitted to cloud storage providers and stored on a remote cloud, ownership and control rights are nonetheless separated. Users thus have significant challenges when attempting to confirm the integrity of private information. According to the experiment results, the suggested dynamic chunking has a fast processing time that is on par with fixed-length chunking and significantly improves deduplication processing capability.

Based on BODIPY fluorescent probe for detecting NO in tumour cells, zebrafish and rice roots under abiotic stresses

As a ubiquitous signaling molecule in organisms and plants, NO plays an important role in their physiological and pathological processes. To date, numerous fluorescent probes have been successfully developed for the detection of NO. However, there are still limitations in the ability to simultaneously detect fluctuations of NO in vivo and plants. In this study, we have developed a fluorescent probe (BZD) specifically probe that reacts with NO under aerobic conditions, leading to a disruption of the photoinduced electron transfer (PeT) process from the secondary amine to the core of BODIPY. This disruption results in the emission of a distinct fluorescent signal. The tests showed that BZD had the advantages of low detection limit (28.4 nM), fast detection time (60 s), and successfully demonstrated good imaging ability in cell, zebrafish. Moreover, the probe was used to detect the changes in NO content in rice roots under abiotic stresses, such as heavy metals and salt stress for the first time. Thus, BZD has significant potential to analyze and detect NO in animal cells and insights into the role of NO in plant signaling.

Augmented reality navigation method based on image segmentation and sensor tracking registration technology

With the rapid development of modern science and technology, navigation technology provides great convenience for people's life, but the problem of inaccurate localization in complex environments has always been a challenge that navigation technology needs to be solved urgently. To address this challenge, this paper proposes an augmented reality navigation method that combines image segmentation and multi-sensor fusion tracking registration. The method optimizes the image processing process through the GA-OTSU-Canny algorithm and combines high-precision multi-sensor information in order to achieve accurate tracking of positioning and guidance in complex environments. Experimental results show that the GA-OTSU-Canny algorithm has a faster image edge segmentation rate, and the fastest start speed is only 1.8 s, and the fastest intersection selection time is 1.2 s. The navigation system combining the image segmentation and sensor tracking and registration techniques has a highly efficient performance in real-world navigation, and its building recognition rates are all above 99%. The augmented reality navigation system not only improves the navigation accuracy in high-rise and urban canyon environments, but also significantly outperforms traditional navigation solutions in terms of navigation startup time and target building recognition accuracy. In summary, this research not only provides a new framework for the theoretical integration of image processing and multi-sensor data, but also brings innovative technical solutions for the development and application of practical navigation systems.

A nanoscale photonic thermal transistor for sub-second heat flow switching

Control of heat flow is critical for thermal logic devices and thermal management and has been explored theoretically. However, experimental progress on active control of heat flow has been limited. Here, we describe a nanoscale radiative thermal transistor that comprises of a hot source and a cold drain (both are ~250 nm-thick silicon nitride membranes), which are analogous to the source and drain electrodes of a transistor. The source and drain are in close proximity to a vanadium oxide (VOx)-based planar gate electrode, whose dielectric properties can be adjusted by changing its temperature. We demonstrate that when the gate is located close ( < ~1 µm) to the source-drain device and undergoes a metal-insulator transition, the radiative heat transfer between the source and drain can be changed by a factor of three. More importantly, our nanomembrane-based thermal transistor features fast switching times ( ~ 500 ms as opposed to minutes for past three-terminal thermal transistors) due to its small thermal mass. Our experiments are supported by detailed calculations that highlight the mechanism of thermal modulation. We anticipate that the advances reported here will open new opportunities for designing thermal circuits or thermal logic devices for advanced thermal management.

Exploring Data Plane Updates on P4 Switches with P4Runtime

The development and roll-out of new Ethernet standards increase the available bandwidths in computer networks. This growth presents significant advantages, enabling novel applications. At the same time, the increase introduces new challenges; higher data rates reduce the available time budget to process each packet. This development also impacts software-defined networks. Their data planes need to keep up with the increased traffic rates. Nevertheless, the control plane must not be ignored; fast reaction times are necessary to handle the increased rates handled by data planes efficiently.In our work, we analyze the interaction of a high-performance data plane and different implementations for the control plane. We selected a P4 switching ASIC as our data plane. For the control plane, we investigate vendor-specific implementations and a standardized implementation called P4Runtime. To determine the performance of the control plane, we introduce a novel measurement methodology. This methodology allows measuring the delay between the initiation of rule updates on the control plane and their application on the data plane. We investigate the behavior of the data plane, its performance and non-atomicity of updates. Based on our findings, we apply different optimization strategies to improve control plane performance. Our measurements show that neglecting the control plane performance may impact network behavior due to delayed updates, but we also show how to minimize this delay and, thereby, its impact. We have released the experiment artifacts of our study including experiment scripts and measurement data.