Tunnel Width Research Articles

Considering the changes in unsaturated soil saturation after pipeline leakage: A modified Terzaghi model

Pipeline leakage leads to the saturation and weakening of the surrounding soil, increasing the pressure exerted by the overlying soil on underground engineering structures and posing a serious threat. Therefore, it is necessary to thoroughly understand the influence of pipeline leakage on the overlying soil pressure. Based on the saturation distribution within different diffusion ranges, an analysis model for pressure in loose soil under the influence of pipeline leakage was presented. Considering the variation in the matric suction of the unsaturated soil, the soil pressure can be modeled based on the incomplete arch effect. The influence of the relevant parameters on the overlying soil pressure was analyzed, and the accuracy and rationality of the modified model were verified using a trapdoor test. These findings indicate that the modified model can accurately estimate the soil pressure caused by a pipeline leakage. The overlying soil pressure is directly proportional to the diffusion distance, tunnel width, and slip surface inclination angle and inversely proportional to the relative deformation. The rate of change was mainly influenced by the parameters affecting the soil arching effect. The modified model presented in this study can be used to directly calculate the overlying soil pressure affected by pipeline leakage. This calculation is based on the known physical and mechanical parameters of unsaturated soil, pipeline leakage range, and relative deformation of the tunnel, thus providing a theoretical basis for the design of structures under urban pipelines.

Predictors of Residual Right to Left Shunt in Patients Undergoing Percutaneous Transcatheter Patent Foramen Ovale Closure: A New Clue "Inferior Vena Cava-Patent Foramen Ovale Angle".

Background: Many different devices are currently used for percutaneous patent foramen ovale (PFO) closure (pPFOc), aiming to achieve complete occlusion to prevent recurrent embolism. We aimed to reveal the association between residual right-to-left shunt (RLS) after pPFOc and baseline structural features of the PFO determined using transoesophageal echocardiography (TEE) before the procedure. Methods: This is a single-center cross-sectional study. A total of 123 patients who underwent pPFOc for cryptogenic stroke (CS) were screened, consecutively. Patients were compared based on the presence of residual RLS. The association of structural features of the PFO with residual RLS was evaluated using logistic regression analysis. Results: The procedure was successfully completed in a total of 103 patients included in the study after exclusion and 21% had significant residual RLS. During a median follow-up of 18 months, one patient died at 25 months due to malignancy, recurrent CS were observed in 5 (5%) patients, and atrial fibrillation was detected in 3 (3%) patients. No significant difference was observed in the baseline clinical characteristics and laboratory parameters among the patients. In addition to atrial septal aneurysm (ASA), aortic rim, tunnel width and length; inferior vena cava (IVC)-PFO tunnel angle was associated with residual RLS with a cut-off 11.3 (AUC: 0.786, 64% sensitivity, 87% specificity, p < 0.001). In individuals with residual RLS, longer and wider tunnel size, rudimentary aortic rim, acute IVC-PFO tunnel angle, and decreased tunnel length-left disc ratio were observed. Conclusions: IVC-PFO tunnel angle is a novel parameter and provides benefit to detect significant RLS in pPFOc patients.

Factors influencing clavicular tunnel widening after single bundle coracoclavicular ligament reconstruction.

The coracoclavicular ligament reconstruction (CLR) technique for the treatment of acromioclavicular joint (ACJ) dislocation has gained immense clinical popularity. However, this technique also has some limitations including complications such as distal clavicle fractures, coracoid fractures, bone tunnel widening, implant failure, and loss of reduction. A study was conducted to analyse the extent of CTW after single-bundle CLR by measuring radiographic parameters to determine its relationship with clinical variables to reduce the risk of clavicular tunnel widening (CTW), thereby providing important insights for clinical practice. This retrospective analysis was conducted at Affiliated Fuyang People's Hospital of Bengbu Medical University, and data from 96 patients who underwent single-bundle CLR for type III-VI ACJ dislocation between January 2018 and December 2023 were initially collected. Finally, 84 patients met the inclusion criteria (63 male and 21 female, mean age: 49.5 ± 12.36 years). The clavicle tunnel (CT) width and coracoclavicular distance (CCD) was measured immediately postoperatively and at 6 months follow up using radiographic imaging, and the degree of expansion at 6 months was recorded. Preoperative variables including patient sex, age, injury cause, injury side, body mass index (BMI), Rockwood classification, extent of the CCD after surgery, and the CT location were recorded to analyze their correlation with the extent of CTW at 6 months follow up. With an average follow-up duration of 10 months (range: 6-18 months). Both the extent of the CCD and CTW measured at 6 months postoperatively were differently enlarged, compared to early postoperative period (EPO) (P < 0.05). The results showed that there were no statistically significant differences in the CTW at 6 months postoperatively with respect to patients' sex, causes of injury, sides of injury, and Rockwood classification types(P > 0.05). However, the location of CT was significantly associated with the extent of CTW at 6 months postoperatively (P < 0.05). The location of CT drilling is a significant factor that affects tunnel widening. When the drilling site is situated closer to the conoid tubercle, the extent of CTW is greater than when the tunnel is located farther from the conoid tubercle.

Anatomical classification of patent foramen ovale before percutaneous closure

Abstract Introduction Anatomical characteristics of patent foramen ovale (PFO) vary a lot, potentially impacting the embolic risk, selection of the device and the final sealing results of the closure procedure. Objective To categorize the different PFO anatomies and evaluate the consequence on the type of device used and the incidence of residual shunt. Methods 624 consecutive patients who underwent PFO percutaneous closure with transoesophageal echocardiography (TEE) guidance were retrospectively reviewed. Four types of PFO were identified once a rigid wire was in place using per-procedural TEE. This new classification was based on the PFO sheathed tunnel’s length and width, presence of concomitant atrial septal aneurysm (ASA) or additional defect (ASD), width of the septum secundum (SS) and aortic enlargement (Figure 1). Type I, or "single PFO" was defined by the absence of ASA or ASD, a tunnel width ≤ 4mm, SS’s width ≤ 10mm and no aortic enlargement (i.e., aortic root diameter &amp;lt;21mm/m², distorted anatomy or scoliosis). Type II or "dominant septal aneurysm" was defined by the presence of an ASA, with a distinction between subtype IIa (long PFO tunnel with length ≥10mm) and subtype IIb (short PFO tunnel with length &amp;lt;10mm). Type III or "modified PFO" was defined by SS’s width &amp;gt; 10 mm, aortic enlargement, or severe scoliosis, and type IV or "multi perforated" was defined by the presence of a concomitant ASD or a multifenestrated septal wall. In case of concomitant criteria, the predominant order was IV, then IIb, then III. For each category, the presence of residual shunt was evaluated after Valsalva manoeuvres with contrast echocardiogram 6 months after the procedure. Results Our population had a median age of 51 [41-59] years and included 43.8% women. The type II PFO was the most frequently encountered, with 42% of the patients (Table 1). A total of 44 (7.1%) patients presented multiple types concomitantly (mostly type II and III). PFO occluders were the most implanted devices overall, particularly with type I and IIb, while ASD occluder were more frequently used with types IV and IIb. Cribriform/Uni™ devices were more frequently used with type IV. Large devices (i.e., left disc’s diameter &amp;gt;25 mm) were predominantly used with type III and IV, but scarcely employed with type I and II. Within type II anatomies, large devices were significantly more frequently used with type IIb. Fluoroscopy duration was significantly higher with type IV. At 6 months ultrasound evaluation, large right-to-left residual shunt was significantly more frequent with type IV anatomy and with patients presenting multiple types concomitantly (18/34 - 40.9%). No significant differences were observed regarding clinical outcomes during follow-up. Conclusion Based on specific anatomical characteristics, four types of PFO may be identified, presenting with increasing procedural complexity, and requesting specific closure devices.

Absence of Additional Stretching-Induced Electron Scattering in Highly Conductive Cross-linked Nanocomposites with Negligible Tunneling Barrier Height and Width.

The intrinsic resistance of stretchable materials is dependent on strain, following Ohm's law. Here the invariable resistance of highly conductive cross-linked nanocomposites over 53% strain is reported, where additional electron scattering is absent with stretching. The in situ generated uniformly dispersed small silver nanosatellite particles (diameter=3.6nm) realize a short tunneling barrier width of 4.1nm in cross-linked silicone rubber matrix. Furthermore, the barrier height can be precisely controlled by the gap state energy level modulation in silicone rubber using cross-linkers. The negligible barrier height (0.01eV) and short barrier width, achieved by the silver nanosatellite particles in cross-linked silicone rubber, dramatically increase the electrical conductivity (51710Scm-1) by more than 4 orders of magnitude. The high conductance is also maintained over 53% strain. The quantum tunneling behavior is observed when the barrier height is increased, following the Simmons approximation theory. The transport becomes diffusive, following Ohm's law, when the barrier width is increased beyond 10.3nm. This study provides a novel strain-invariant resistance mechanism in highly conductive cross-linked nanocomposites.

The underground cat: burrow use by female black-footed cats (Felis nigripes)

The black-footed cat (Felis nigripes) is the smallest and one of the rarest cats in Africa. Endemic to the semi-arid regions of South Africa, Namibia and Botswana, this nocturnal carnivore spends daytime in burrows, thus avoiding high temperatures and diurnal predators. Despite the importance of burrows, den usage has never been studied in detail for this species. Here we report on the frequency with which female black-footed cats use burrows of different dimensions and compared with burrow availability. The entrances of 50 dens, used by five radio-collared black-footed cats over four weeks, were scanned with LiDAR to measure tunnel width (mean = 15.2 ± 3.9 cm) and height (mean = 13.9 ± 3.6 cm). Of these, 98% (n = 49) most closely matched the dimensions of springhare (Pedetes capensis) burrows. Each cat used a mean of 11.6 den sites and spent a mean of 2.0 consecutive days in a den before selecting a new one. When kittens reached an age of 44–50 days, mothers switched from using a den for a mean of six days-per-den, to changing dens every day. Our results suggest that female black-footed cats are reliant upon springhares to provide suitable daytime refugia and maternity dens in southern Namibia. Further studies should be conducted to determine what den sites are selected in the absence of springhare, and whether localised persecution of springhare impacts the survival of black-footed cats.

Radiographic Tibial Tunnel Assessment After Anterior Cruciate Ligament Reconstruction Using Hamstring Tendon Autografts and Biocomposite Screws: A Prospective Study With 10-Year Follow-up.

Biocomposite screws reportedly provide equivalent graft fixation in anterior cruciate ligament reconstruction (ACLR) to metallic screws while simplifying subsequent imaging and surgery. One purported complication of biocomposite screws is paradoxical tunnel widening. Previous studies on beta-tricalcium phosphate screws have only reported outcomes at short- and midterm follow-up. To radiographically assess the tibial tunnel 10 years after ACLR using hamstring tendon autografts and biocomposite interference screws in anatomic single-bundle (SB) and double-bundle (DB) methods. Case series; Level of evidence, 4. Of the 105 initially recruited patients, 61 (58%) completed all follow-up evaluations for inclusion in this long-term study. A total of 26 patients received anatomic SB ACLR and 35 patients received DB ACLR with biocomposite interference screws containing beta-tricalcium phosphate in the tibia. Weightbearing anteroposterior and lateral radiographs of the index knee were taken in the early postoperative period and at 2, 5, and 10 years postoperatively; computed tomography (CT) imaging was performed at 10-year follow-up. Subjective and objective clinical assessments were recorded preoperatively and at 10-year follow-up. The mean follow-up period was 122 months. In 76% of radiographs in the SB group, the width of the tibial tunnel had not increased at 10 years compared with the early postoperative period. The mean tibial tunnel volume on CT in the SB group was 2.04 cm3 (± 0.85 cm3). In the DB group, the posterolateral tunnel width had not increased in 69% of radiographs; the same was found in 63% of radiographs for the anteromedial tunnel at 10-year follow-up. The mean posterolateral tunnel volume on CT was 2.04 cm3 (±1.92 cm3) and the mean anteromedial tunnel volume was 1.38 cm3 (±0.54 cm3). There was no correlation between tunnel widths and KT-1000 arthrometer assessments. There was a moderate but statistically significant correlation between SB tibial tunnel volume on CT imaging and KT-1000 arthrometer anterior 134 N side-to-side difference (r = 0.45; P = .039). Most patients' tibial tunnels had not increased on 1 or both radiographic views at 10-year follow-up compared with the early postoperative period after ACLR using biocomposite interference screws, with no obvious negative effect on outcomes. However, the tunnels were still visible in most patients at 10 years on standard radiographs and CT imaging.

Influence of procedural timing on the preventive yield of percutaneous patent foramen ovale closure

BackgroundThe benefit of patent foramen ovale closure (PFOC) ≤9 months after a cryptogenic stroke has been demonstrated in several randomised clinical trials. There is, however, insufficient data to support PFOC...

Numerical study on smoke temperature distribution in naturally ventilated inclined tunnels: Effects of tunnel width and tunnel slope

Inclined tunnel fires exhibit unique characteristics compared to horizontal tunnel fires as a result of the stack effect. Nevertheless, there is still a lack of consensus among previous scholars regarding the smoke temperature distribution in inclined tunnel fires. This work conducts a numerical investigation on the smoke back-layering length upstream of the fire source and the temperature decay downstream of the fire source in naturally ventilated inclined tunnels with varying widths and slopes. Results indicate that as the tunnel slope increases from 0° to 8°, the smoke back-layering length first decreases and then continues at a constant value of 1.47H4/3/W1/3, while the effect of tunnel width is negligible. The decay factor in the one-dimensional flow stage (x/H≥4) exhibits two distinct patterns related to tunnel width: it initially remains constant and then drops when the tunnel is wide, whereas it monotonically drops when the tunnel is narrow. Two empirical models are developed to identify the segmented characteristics and verified through the relevant data from existing literature with similar fire scenarios. This work offers a method for estimating the smoke temperature distribution in inclined tunnels, providing crucial insights for fire prevention, smoke detection, and safety strategies in tunnel engineering.

Ultra-broadband illusion acoustics for space and time camouflages

Invisibility cloaks that can suppress wave scattering by objects have attracted a tremendous amount of interest in the past two decades. In comparison to prior methods that were severely limited by narrow bandwidths, here we present a practical strategy to suppress sound scattering across an ultra-broad spectrum by leveraging illusion metamaterials. Consisting of a collection of subwavelength tunnels with precisely crafted internal structures, this illusion metamaterial has the ability to guide acoustic waves around the obstacles and accurately recreate the incoming wavefront on the exit surface. Remarkably, two ultra-broadband illusionary effects are produced, disappearing space and time shift. Sound scatterings are removed at all frequencies below a limit determined by the tunnel width, as confirmed by full-wave simulations and acoustic experiments. Our strategy represents a universal approach to solve the key bottleneck of bandwidth limitation in the field of cloaking in transmission, and establishes a metamaterial platform that enables the long-desired ultra-broadband sound manipulation such as acoustic camouflage and reverberation control, opening up exciting new possibilities in practical applications.

A complementary approach to quantify the basic GSI chart considering scale effect on rock structure

Geological strength index (GSI) has been widely used as an input parameter in predicting the strength and deformation properties of rock masses. This study derived a series of equations to satisfy the original GSI lines on the basic GSI chart. Two axes ranging from 0 to 100 were employed for surface conditions of the discontinuities and the structure of rock mass, which are independent of the input parameters. The derived equations can analyze GSI values ranging from 0 to 100 within ±5% error. The engineering dimensions (EDs) such as the slope height, tunnel width, and foundation width were used together with representative elementary volume (REV) in jointed rock mass to define scale factor (sf) from 0.2 to 1 in evaluating the rock mass structure including joint pattern. The transformation of GSI into a scale-dependent parameter based on engineering scale addresses a crucial requirement in various engineering applications. The improvements proposed in this study were applied to a real slope which was close to the time of failure. The results of stability assessments show that the new proposals have sufficient capability to define rock mass quality considering EDs.

Ambipolar current suppression in drain elevated TFET using a novel extended drain structure with a moderate doping profile

In this paper, a simple and compact silicon-based Elevated and Extended Drain with Hetero-Dielectric Gate Oxide TFET (EED HDGO TFET) is proposed to suppress the ambipolar current in Elevated Drain TFET (ED TFET). The proposed device structure uses a moderately doped drain with a doping concentration of ∼1018 cm−3 and a high drain length of ∼50–100 nm. The combination of the moderate drain doping profile and the extended drain length reduced the impact of the electrostatic potential from the positive voltage of the drain electrode on the channel–drain junction. This structural technique widens the tunneling width at the channel–drain region causing the tunneling current to decrease significantly. The tunneling width is further increased by structurally isolating the channel–drain junction region from the gate electrode. Thus, distancing the channel–drain junction from both the gate electric field and the static drain potential of the drain electrode causes full suppression of the ambipolar (Iamb) current. The proposed structure yields Iamb and Ioff as low as ∼10−18 A/μm and ∼10−17 A/μm respectively, while maintaining the Ion as ∼0.3 mA. The device is optimized for low power and high-speed digital circuits through intensive parametric analysis on gate–drain Cgd and the gate–source Cgs capacitances for various device parameters.

Taylor droplet breakup in T-type microchannels: A detailed flow analysis

The study of droplet break-up in microchannels can be used to improve designs for both biological or chemical microreactors and microfluidic devices e.g., heat exchangers and microchips. In this study, 3D computer simulations were carried out to investigate the detailed behavior of droplet breakup in a T-junction microchannel using the Volume of Fluid (VOF) and Level Set (LS) coupling methods (S-CLSVOF) implemented in OpenFoam. The evolution of droplet morphology and the rupture regimens were analyzed considering pressure results, velocity neck thickness, and tunnel width. The results show four rupture regimes for a range of capillary numbers and dimensionless initial droplet length of 0.005≤Ca≤0.055 and 1≤l0/w≤5. The stages of each rupture were also analyzed and compared with experimental and numerical results from literature. A detailed description of each step in the droplet breakup is also given, including analyses of the influence that the local pressure field and Laplace pressure have on the rupture processes. The 3D results reveal that the Laplace pressure decreases in the main channel due to continuous flux at the top and bottom of the 3D channel. This in turn, leads to a slight change in the rear curvature of the bubble. Laplace pressure is an important parameter that can be used to predict the opening tunnel point, large changes in curvature, and whether the droplet will breakup or not. Just before breakup, the 3D simulations captured a backflow near the neck, a region, characterized by pressure drops, and thus smaller breakup times.

GaSb/Si Heterojunction Based Pocket Engineered Vertical Non-Uniform Channel Double Gate TFETs for Low Power Applications

This article compares the performance of two Vertical Non-Uniform Channel Double Gate Tunnel Field Effect Transistors (VNUCDGTFETs), a normal all-Silicon Tunnel Field-Effect Transistor (TFET) having a pocket and another one a Gallium Antimonide/Silicon heterojunction TFET with pocket. GaSb is a III-V narrow energy band gap material, employed in the source area of the TFET structure to decrease the tunneling width and thus to make more number of carriers capable enough to tunnel through the heterojunction. The proposed source pocket heterojunction non uniform channel TFET presents superior performance as compared to the conventional non uniform channel vertical TFET with a pocket, regarding a larger ION/IOFF ratio, a reduced sub-threshold swing, and a smaller threshold voltage at VDS = 0.5 V. Furthermore, the proposed TFET device undergoes a comprehensive analysis of both DC parameters and various analog/RF parameters.

A tentative study on the effect of tunnel width on the maximum temperature under the ceiling in tunnel fires

Maximum gas temperature under the ceiling in tunnel fires has been studied experimentally and numerically. Full scale burning test in tunnel with length 100 is carried out. Three different pool fires with approximate maximum heat release rate of 0.6, 1.0 and 5MW were set up. The smoke temperature is collected by the Fiber-optic Bragg grating system. CFD simulations were carried out to study the effect of tunnel width on the maximum temperature. By analyzing the experimental and numerical simulation results, a critical point of ratio B/H and two stages concerning the varying of B/H are proposed to clarify the influence of tunnel width, meanwhile we conclude that it is interdependent between the ratio of H/B and the ventilation velocity when discussing the maximum gas temperature in tunnel fires.

Thin-body effects in double-gate tunnel field-effect transistors

Scaling down the body thickness (T b) of double-gate tunnel field-effect transistors (DG-TFETs) is helpful in suppressing short-channel effects, but it may give rise to thin-body effects (TBEs). Based on 2D device simulations, this study examines the mechanisms and influences of TBEs in DG-TFETs as T b is scaled down. Differently from previous beliefs, the on-current degradation in thin-body DG-TFETs is not mainly caused by the volume effect, but rather by a newly defined TBE named lateralization effect. This is because the lateralization of tunneling direction significantly increases tunnel width, whereas the reduction of tunneling volume is quite limited due to narrow tunneling regions. To study the T b-dependence of current, therefore, the vertical tunneling has to be taken into consideration. When considered as a TBE, the fringing field effect caused by reduction in T b is not significant in degrading the on-current of thin-body DG-TFETs because the narrow tunneling regions are strongly gate-controlled. The only TBE that enhances the on-current is the coupling effect, but its role is only significant for low-bandgap bodies in which the coupling effect can efficiently promote the tunneling towards the body center. Not as previously thought that the quantum confinement effect monotonically increased, it even decreases as T b decreases down to sub-10 nm before turning to increase, thanks to the space sharing between proximate local quantum wells. A comprehensive understanding of the TBEs is useful for providing design insight, especially for determining the optimal T b to maximize the on-current.

Effect of width and slope of large cross-section tunnel on ceiling smoke temperature under natural ventilation

ABSTRACT When a fire occurs in a large cross-section tunnel with slope, the distribution characteristic of ceiling smoke temperature illustrates special laws under the effect of chimney effect, the thermal radiation feedback, and the air entrance limit from walls. A series of numerical simulations are conducted through FDS simulation software based on the actual size of highway tunnel. The influence of large cross-section tunnel width and slope on ceiling smoke temperature when fire occurs are discussed. The research results show that (1) as the tunnel slope increases from 5° to 20°, the distance between the maximum ceiling smoke temperature point and the fire source is 0.5 m, 1 m, 1.7 m, 2.4 m, respectively, and the distance between the ceiling impact point and the fire source is 1 m, 1.8 m, 2.3 m, 3 m, respectively. As the tunnel width increases from 10 m to 20 m, the distance between maximum ceiling smoke temperature point and fire source increases 0.9 m, 1.1 m, 1.3 m, 1.8 m, 2.5 m, and 2.6 m. (2) The prediction formula of maximum ceiling smoke temperature is modified, and a dimensionless relationship among the maximum ceiling smoke temperature and tunnel slope and tunnel width is established. (3) The formula of longitudinal ceiling smoke temperature distribution is modified, and the relationship among tunnel slope, tunnel width, tunnel height, and longitudinal ceiling smoke temperature distribution is established. The research conclusions can provide a theoretical basis for fire prevention design, smoke control and evacuation of this kind of large cross-section tunnel fire.

Tailoring Contacts for High-Performance 1D Ta2Pt3S8 Field-Effect Transistors.

Materials with van der Waals (vdW) unit structures rely on weak interunit vdW forces, facilitating physical separation and advancing nanomaterial research with remarkable electrical properties. Recently, there has been growing interest in one-dimensional (1D) vdW materials, celebrated for their advantageous properties, characterized by reduced dimensionality and the absence of dangling bonds. In this context, we synthesize Ta2Pt3S8, a 1D vdW material, and assess its suitability for field-effect transistor (FET) applications. Spectroscopic analysis and electrical characterization confirmed that the band gap and work function of Ta2Pt3S8 are 1.18 and 4.77 eV, respectively. Leveraging various electrode materials, we fabricated n-type FETs based on Ta2Pt3S8 and identified Cr as the optimal electrode, exhibiting a high mobility of 57 cm2 V-1 s-1. In addition, we analyzed the electron transport mechanism in n-type FETs by investigating Schottky barrier height, Schottky barrier tunneling width, and contact resistance. Furthermore, we successfully fabricated p-type operating Ta2Pt3S8 FETs using a molybdenum trioxide (MoO3) layer as a high work function contact electrode. Finally, we achieved Ta2Pt3S8 nanowire rectifying diodes by creating a p-n junction with asymmetric contact electrodes of Cr and MoO3, demonstrating an ideality factor of 1.06. These findings highlight the electronic properties of Ta2Pt3S8, positioning it as a promising 1D vdW material for future nanoelectronics and functional vdW-based device applications.

Sensitivity Analysis of a Double Source Stack Lateral TFET-Based Gas Sensor

Metal oxide semiconductor gas sensors are used recently in various roles and sectors for environmental safety as compared to other sensing technology due to its low cost, durability, longevity, and rapid sensing capability under humid condition. The current work proposes a dual stacked heterogeneous source lateral n type tunnel field-effect transistor (DSHS-nTFET) for gas sensing applications. The proposed device investigates the characteristics of the gas response. The stack source is designed to make it easier for electrons to tunnel through the tunnel barrier effectively so that the device sensitivity can be enhanced. In the device’s tunneling junction, the presence of the source stack boosts the electric field, reduces tunneling width, and then enhances the band-to-band tunneling. The gas density can be detected by modulating the work function of the metal gate present in the device. Catalytic metals used as gate contacts for this proposed double source stacking TFET design are explored for the purpose of detecting specific gases. Platinum (Pt), Cobalt (Co), Palladium (Pd), and Silver (Ag) are the metal gate electrodes utilised in this work to sense the target gases, like Carbon-mono Oxide (CO), Ammonia (NH3), Hydrogen (H2), and Oxygen (O2) respectively. The detection has been done by the electrodes work function variation due to the presence of gas density of the target gases. With the aid of the Sentaurus TCAD simulator, the suggested structure has been examined for a number of electrical parameters including electric field, surface potential, drain current, and numerous sensing characteristics pertaining to adsorption of gas molecules. According to the data achieved, the suggested DSHS-nTFET device displays a high Ion of 5.06 × 10−5 A/μ m, a low Ioff current of 3.76 × 10−20 A/μm, and also the Ion/Ioff ratio in the range of 1014. Furthermore, sensitivity parameters for DSHS-nTFET have also been examined and shown to be significantly improved. The sensitivity and reliability of the proposed sensor have also been investigated with respect to temperature fluctuations. It has been shown that the device is largely stable over the 200 K-400 K range.

Deroofing: A safe, effective and well-tolerated procedure in patients with hidradenitis suppurativa.

Hidradenitis suppurativa (HS) is a recurrent, debilitating, chronic disorder of the pilosebaceous unit. Although advances in HS treatment have been made, more than 45% of patients remain dissatisfied with systemic treatment, and more than one-third are dissatisfied with surgical procedures. A prospective, observational study on the deroofing procedures in HS with special attention paid to patient satisfaction and complications. HS lesions were assessed clinically and by the use of ultrasound. Patients reported outcomes, including pain, itch and satisfaction, were measured at 24 h post-surgery by a numeric rating scale (NRS) ranging from 0 to 10. Additionally, the timeline of objective wound closure reported by patients in (weeks), in addition to the need for any analgesics use, were both evaluated. The mean closure time of the post-deroofing wound was assessed as 4.4 ± 1.9 weeks. A statistically longer time was necessary for complete closure in males than in females (4.9 ± 2.2 weeks and 3.9 ± 1.6 weeks, respectively; p = 0.046). The closure time correlated positively yet weakly with the HS tunnel's width (r = 0.27, p = 0.016) and length (r = 0.228, p = 0.044). Patients assessed mean pain at 24 h post-op as mild with 0.7 ± 1.2 points according to NRS, with no differences between sexes. Similarly, itch in the first 24 h was assessed as mild with 1.8 ± 1.1 points, without differences between sexes. No pain, itch or adverse events were reported after 1 week following deroofing. Moreover, no cases of wound infection were reported. An overall patient satisfaction was assessed as 9.9 ± 0.4 points (range 9-10 points). Deroofing is an easy, effective and safe dermatosurgical procedure that does not require surgical experience or operating theatre. It is associated with no complications and very low post-op pain and should be part of holistic HS management.