Single Drain Research Articles

Design and Analysis of Dual Source Vertical Tunnel Field Effect Transistor for High Performance

An optimally designed Dual Source Vertical Tunnel Field Effect Transistors is proposed and investigated using technology computer aided design simulation. The vertical tunnel FET have dispersal of source channel drain in the vertical direction which will enhance the scalability of the simulated device. The benefit of the TFET is switching mechanism which is done by quantum tunnelling method through a barrier instead of thermionic emission over the barrier as that of conventional MOSFETs. The key of this paper, we have developed two-dimensional model of single drain with dual source n-type vertical tunnel field effect transistor. Further introduction to an ultra-thin channel among the drain and gate region will makes aggressive improvement in the numerical simulations of minimum threshold voltage (VT) of 0.15 V and average subthreshold slope of 3.47 mV/decade. The variation effect in the channel thickness, source height, drain doping, source doping, temperature and work function has been simulated and examined by 2D silvaco TCAD tool. High ON current and low OFF current is recorded as 1.74 × 10−4 A/µm and 6.92 × 10−13 A/µm respectively with ION/IOFF current ratio in order of 108 to 109.

Do we need more than one mediastinal drain in cardiac surgery?

Background: Placement of mediastinal drains after cardiac surgery is standard of care. However, there is no consensus over the number of drains to be placed. Is there any advantage of multiple drains over a single drain? This question formed the premise of this study.Methods: All consecutive patients operated between 2014 and 2015 were included. Those with pleural drains were excluded. Patients had either a single drain in the pericardial cavity or had two drains, one in the pericardial and the other in retrostenal area. A total of 244 patients were included in the study group.Results: Out of 244 patients, 122 had single drain and 122 had 2 mediastinal drains. The mean age was 24.38±17.08 (Age range 6 months to 66 years) and male: female ratio was 1.5:1. There was no statistically significant difference in single drain vs double drain group in terms of the number of days of drainage (1.65 vs 1.55, p 0.325), time to mobilize (36.57 vs 35.23 hours, p=0.684), ICU stay (2.62 vs 2.63 days, p=0.96)and re-exploration (5.7%, vs 9.8%, p=0.34). However, patients with two mediastinal drains had higher requirement of analgesia (p=0.004).Conclusions: The use of two mediastinal drains does not confer any advantage over a single mediastinal drain after cardiac surgery in assessing or controlling bleed or recovery. However, the post-operative pain is significantly higher with use of two mediastinal drains.

Capacity for bioreactors and riparian rehabilitation to enhance nitrate attenuation in agricultural streams

Globally, small agricultural waterways fed by springs, tile drains, and seeps can disproportionately contribute to downstream nutrient loading, which is associated with declines in water quality and ecosystem functions. Treating nitrate using a multiple tool, multiple-scale approach in small waterways could offer improved management of these sources. We used a before-after-control-impact design to test the suitability of three small (<30 m3) edge-of-field denitrifying woodchip bioreactors and stream bank re-shaping and riparian planting. Over three-and-a-half-years, riparian rehabilitation enhanced nitrate flux attenuation compared to pre-rehabilitation, but only under relatively low flow conditions. In comparison, there were no significant changes in nitrate flux in a control waterway under any flow condition. N fluxes always increased in both the control and treatment waterways when reaches gained water downstream. Nitrate removal efficiencies for all three bioreactors ranged from <10 to >99%, with performance variations due to short residence times and fluctuations in source water chemistry. A single tile drain bioreactor removed 0.41 kg NO3-N d−1, equivalent to ∼10% of the mean daily tile drain nitrate load. Greenhouse gas fluxes from the tile drain bioreactor were similar to the surrounding pasture (CO2-C mean: 185–286 mg C m2 h−1; N2O-N mean: 49–90 μg N m2 h−1), suggesting no negative impacts from the bioreactor. Overall, our results suggest a multiple-tool, multiple-scale application of rehabilitation tools can reduce downstream N fluxes, but only under certain flow conditions. Thus, local rehabilitation tools, like those trialed here, will need to be scaled appropriately if they are to significantly attenuate nutrient losses from small agricultural waterways. Moreover, these will not replace catchment-scale nutrient plans to address losses from land and legacy groundwater N pollution.

Impact of closed suction drainage after surgical fixation of acetabular fractures.

The purpose of the present study was to evaluate the prevalence of closed suction drainage after a Kocher-Langenbeck (K-L) approach for surgical fixation of acetabular fractures and to determine the impact of closed suction drainage on patient outcomes. This retrospective study reports on 171 consecutive patients that presented to a single level I trauma center for surgical fixation of an acetabular fracture. Medical records were reviewed to evaluate the use of closed suction drains. The primary outcomes measures were rate of packed red blood cell (PRBC) transfusion and length of hospital stay (LOS). Secondary outcome measures were 30-day post-operative wound complication and 1-year deep infection rates. Of the 171 patients included in this study, 140 (82%) patients were treated with drains. There was a significant association between the use of closed suction drainage and post-operative blood transfusion rate (p = 0.002). Thirty-five patients (25%) treated with drains required a post-operative blood transfusion compared to 0% in the no drain cohort. Regarding the total number of drains used, for every additional closed suction drain that was placed beyond a single drain, the odds of receiving a blood transfusion doubled (p = 0.002). Use of closed suction drainage was associated with a significantly longer LOS (p = 0.015), and no difference in wound complication or deep infection rates. The use of closed suction drains for treatment of acetabular fractures using a K-L approach is associated with increased rates of blood transfusion and increased length of hospital stay, with no impact on surgical site infection rates. The results of this study suggest against routine drain usage in acetabular surgery.

Approach to pneumothorax surgery: a national survey of current UK practice.

Pneumothorax is a common condition with various management options. We aimed to determine the current surgical practice in the United Kingdom. An online questionnaire regarding surgical strategy was sent to all consultants who were members of the Society for Cardiothoracic Surgery (80 thoracic). Fifty-six consultants, mainly thoracic, responded to the survey. Video-assisted thoracoscopic surgery was unanimously the preferred approach, the majority (59%) using 3 ports. Regarding the timing of surgery, 53 (95%) surgeons would intervene at first presentation with persistent air leak and/or lung collapse, 41 (73%) for a first bilateral pneumothorax, 22 (39%) only for recurrent pneumothorax, and 18 (32%) for the first computed tomography evidence of bullae. Apical bullectomy + pleurectomy was the preferred technique for 26 (46%) surgeons, and apical bullectomy + apical pleurectomy + pleural abrasion was the choice for 13 (23%). Some surgeons were concerned about talc and avoid it. The majority (70%) used a single apical drain with or without 24-48 h suction. Regarding chest radiography, the response was variable but 48% performed immediate postoperative and/or daily chest radiographs. Currently, most surgeons (59%) use digital drains and feel it monitors air leaks better. The perceived chronic pain (1%-3%) and recurrence rates (0%-3%) were stated by 59% and 86%, respectively. There is variability in the surgical management of pneumothorax among surgeons across the UK, but they all use video-assisted thoracoscopic surgery as the intervention of choice for pneumothorax surgery, and there is a shift towards early surgical intervention.

The symmetric draining of capillary liquids from containers with interior corners

A new lubrication model solution is found for the late-stage draining of a wetting capillary liquid from a linear interior corner. The solution exploits the symmetry of volumetric sink conditions at opposing ends of such a ‘double-drained’ interior corner flow with applications ranging from liquid recovery in microfluidic devices on Earth to liquid fuel scavenging in large fuel tanks aboard spacecraft. At long times $t$, the nominal liquid depth is $h\sim t^{-1}$, the liquid volume is $V\sim t^{-2}$ and the maximum volumetric liquid removal rate is $Q\sim t^{-3}$. The constraints under which the solution is valid are provided. To qualitatively assess the value of the solution, representative experiments are conducted at larger length scales aboard the International Space Station and at microfluidic length scales in a terrestrial laboratory. Both sets of experiments confirm the predicted power-law dependences. We show that the separation of variables solution offers a method to predict maximum drain rates from related geometries where a single drain location provides the required symmetry of the problem.

Feasibility of a single mediastinal drain through the abdominal wall after esophagectomy.

This study evaluated the safety and effectiveness of a single mediastinal drainage tube in the thoracic and abdominal cavity after minimally invasive esophagectomy (MIE). This study was undertaken to determine if the procedure could be included in a fast-track surgery program for resectable esophageal carcinoma (EC).From June 17 to November 30, 2015, clinical data for 78 eligible patients who had undergone a fast-track surgery program and MIE were retrospectively analyzed. Twenty-eight patients had a chest tube and mediastinal drainage tube. Thirty-four patients had only a mediastinal drainage tube through the intercostal space. The remaining 30 patients had a single mediastinal drainage tube in the thoracic and abdominal cavity through the abdominal wall. The complication rates and pain scores for each of the groups were compared. The statistical calculations were performed using SPSS 17.0 for Windows (SPSS Inc., Chicago, IL). The quantitative data among the groups were compared using 1-way analysis of variance (ANOVA). The Chi-square, Mann–Whitney U and Fisher exact tests were used for qualitative data analysis.There were no significant differences in the anastomotic leak rates, postoperative days and total complication rates (P = .861). The lowest visual analog scale (VAS) scores of the drainage tubes were observed in the group with a single mediastinal drain through the abdominal wall (P <.001).The results of this study suggested that a single mediastinal drainage tube in the thoracic and abdominal cavity after MIE may be safe and efficient. This clinical practice is a part of our fast-track surgery program.

Optimal management of postoperative parenchymal air leaks.

Air leaks are the most common complication after pulmonary resection. Enhanced recovery after surgery (ERAS) programs must be designed to manage parenchymal air leaks. ERAS programs should consider two components when creating protocols for air leaks: assessment and management. Accurate assessment of air leaks using traditional analogues devices, newer digital drainage systems, portable devices and chest X-rays (CXR) are reviewed. Published data suggests that digital drainage systems result in a more confident assessment of air leaks. The literature regarding the management of postoperative air leaks, including the number of chest tubes, the role of applied external suction, invasive maneuvers and discharge with a portable device is reviewed. The key findings are that a single chest drain is adequate in the majority of cases to manage an air leak, the use of applied external suction is unlikely to prevent or prolong an air leak, autologous blood patch pleurodesis may potentially shorten postoperative air leaks and there is sufficient data to support that patients can safely be discharged with a portable drainage system. There is also literature to support the design of protocols for management of postoperative air leaks. Standardization of postoperative care through ERAS programs will allow for the design of larger RCTs to better understand some of the controversies around the management of postoperative air leaks.

Limax Nd:YAG laser-assisted thoracoscopic resection of pulmonary metastases; a single centre's initial experience.

Pulmonary metastasectomy and indeed redo-pulmonary metastasectomy are now commonly performed thoracic surgical procedures. The air-sealant, haemostatic, and necrotic properties of the KLS Martin Limax Nd:YAG laser at 1.318μm make it an ideal tool for limited lung resection such as metastasectomy. We present our initial experience of thoracoscopic laser metastasectomy. We reviewed data from the first seven patients in our unit to undergo thoracoscopic laser metastasectomy, in particular, patient age, gender, primary malignancy, primary treatment, complications, length of stay (LOS), and final histopathology. All procedures were performed using a two- or three-port thoracoscopic technique with some lesions requiring CT-guided wire localisation. A single drain was inserted via the camera port site and was removed upon confirmation that there was no air leak. Seven patients underwent thoracoscopic laser wedge metastasectomy of eight lesions in our centre between February 2017 and October 2017. The median age was 61years. The primary disease was colorectal carcinoma in five cases, eccrine carcinoma in one case, and high-grade uterine leiomyosarcoma in one case. Only one patient had a prolonged air leak in the other six cases; the drain was removed on post-operative day 1. The median post-operative LOS was 1day. All patients had confirmed metastatic disease with clear resection margins on histopathology. In our early experience, thoracoscopic laser wedge metastasectomy is a safe and efficient method for performance of pulmonary metastasectomy. We experienced a low complication rate and a short post-operative stay.

Real-time ultrasound-guided pigtail catheter chest drain for complicated parapneumonic effusion and empyema in children \u2013 16-year, single-centre experience of radiologically placed drains

BackgroundChest tube drainage with fibrinolytics is a cost-effective treatment option for parapneumonic effusion and empyema in children. Although the additional use of ultrasound (US) guidance is recommended, this is rarely performed in real time to direct drain insertion.ObjectiveTo evaluate the effectiveness and safety of real-time US-guided, radiologically placed chest drains at a tertiary university hospital.Materials and methodsThis was a retrospective review over a 16-year period of all children with parapneumonic effusion or empyema undergoing percutaneous US-guided drainage at our centre.ResultsThree hundred and three drains were placed in 285 patients. Treatment was successful in 93% of patients after a single drain (98.2% success with 2 or 3 drains). Five children had peri-insertion complications, but none was significant. The success rate improved with experience. Although five patients required surgical intervention, all children treated since 2012 were successfully treated with single-tube drainage only and none has required surgery.ConclusionOur technique for inserting small-bore (≤8.5 F) catheter drains under US guidance is effective and appears to be a safe procedure for first-line management of complicated parapneumonic effusion and empyema.

Characterization of cover-collapse sinkhole morphology on a groundwater basin-wide scale using lidar elevation data: A new conceptual model for sinkhole evolution

In karst regions of the world, identifying areas that are inherently unsafe for certain types of land use is crucial. High-resolution lidar elevation data for the Illinois sinkhole plain have exposed previously unnoticed geomorphologic details. Analysis of these data has revealed a pattern of long-term evolution of cover-collapse sinkholes within the groundwater basins. The leading edge of a groundwater basin is known to be the site of progressively enlarging bedrock crevices and conduits that encroach into groundwater divides. In karst areas of the U.S. Midwest, runoff creates surface streams at groundwater divides that flow into groundwater basins and form disappearing streams. Using this pattern as a starting point, we developed a new conceptual model of cover-collapse sinkhole development and evolution within groundwater basins. As the boundaries of a groundwater basin migrate outward for tens of thousands of years, stream-valley-shaped sinkholes at the leading edge seemingly migrate deeper into the basin. The stream-valley sinkholes then form numerous drains, join other sinkholes through erosion and collapse along sinkhole boundaries, and eventually become areally extensive and irregularly shaped compound sinkholes. Continued erosion of fine-grained sediment overlying bedrock near the distal end of the groundwater basin reduces the elevation of land surface until nested sinkholes within the compound sinkholes become simple sinkholes with a single drain point. Near the discharge points of the groundwater basin, the individual drains associated with the simple sinkholes partition the remaining upland surface, forming a pattern of Thiessen or Voronoi polygons resulting from surface runoff among adjacent sinkholes.

Double to Single Chest Drain Following Empyema Decortication: Outcome Analysis

Background: The insertion of a single chest drain (CD) rather than a double CD following thoracic procedures is becoming common practice. Less postoperative pain, easy mobility, and chest physiotherapy are advantages. The outcome of this practice following decortication for empyema is yet to be documented in the literature.

集合住宅対応サイホン排水システムの実用化に関する研究 （第12報）単独系統の合流での器具排水における排水立て管システムの実験

集合住宅対応サイホン排水システムの実用化に関する研究 （第12報）単独系統の合流での器具排水における排水立て管システムの実験

Uniportal video-assisted thoracic surgery for esophageal cancer.

Classical video-assisted thoracic surgery (VATS) approach to esophageal cancer uses four incisions. The rationale is to facilitate movement of the instruments and the esophagus and also suturing during placement of a purse-string suture for an intrathoracic anastomosis. Uniportal VATS (U-VATS) is challenge for surgeons, as you have to do an esophageal mobilization and anastomosis from a single 3-5 cm incision. The incision is placed either at the 5th or 6th intercostal space close to the posterior axillary line. Esophagus is mobilized en bloc with the subcarinal and periesophageal lymph nodes. The crucial parts are inclusion of subcarinal lymph node in the specimen, mobilization of the specimen from the left main bronchus and esophagogastric anastomosis. Esophagus is encircled with a thick penrose drain and retracted anterior and posteriorly during this dissection. Once the esophagus is completely mobilized, if an intrathoracic anastomosis is to be performed, gastric conduit is pulled inside the chest in correct orientation. A linear completely stapled side to side anastomosis is performed. A thick tissue endoscopic stapler is used for posterior and anterior wall. A single chest drain is placed and incision is closed. There are several intrathoracic anastomotic techniques. All of these techniques can be applied through a uniportal approach. Side to side completely stapled anastomosis is safe, fast and easy to perform. There is a single report on esophagectomy comparing uniportal and multiportal VATS approaches in esophageal cancer which showed comparable results in terms of duration of surgery, amount of bleeding, lymph node yield and leak rates. U-VATS for esophageal cancer is emerging as a new approach and the technique is feasible and certainly future studies will show if it is reproducible and provides a clinical advantage for the patient.

A New Method for Series Resistance Extraction of Nanometer MOSFETs

This paper presents a new method for the series resistance extraction in ultimate MOSFETs using a single drain current versus gate voltage characteristic curve. The method is based on the Y-function curve, such that the series resistance is obtained through the curve of the total resistance as a function of the inverse of the Y-function. It includes both first- and second-order mobility degradation factors. To validate the proposed method, numerical simulations have been performed for devices of different characteristics. Besides, the method applicability has been demonstrated for experimental silicon nanowires and FinFETs. Apart from that, devices with different channel lengths can be used to estimate the mobility degradation factor influence.

First Hands-On Experience with the Application of a Newly Designed Double-Branched Thoracic Catheter for Thoracic Interventions.

Background We investigated the technical handling of a y-shaped double-branched thoracic catheter with the aim of combining the effect of two separate catheters and the ease of use of a single one. Methods A total of 20 catheters were placed consecutively in 20 patients. Results In all patients, it was technically simple to position the catheter, whether in open or video-assisted surgery. The handling during removal corresponded to that of a single drain. Conclusion This type of drain appears to hold a lot of potential compared with the use of a single drain. Further studies with defined and larger patient populations should be performed.

Drain Current Modulation of a Single Drain MOSFET by Lorentz Force for Magnetic Sensing Application.

This paper reports a detailed analysis of the drain current modulation of a single-drain normal-gate n channel metal-oxide semiconductor field effect transistor (n-MOSFET) under an on-chip magnetic field. A single-drain n-MOSFET has been fabricated and placed in the center of a square-shaped metal loop which generates the on-chip magnetic field. The proposed device designed is much smaller in size with respect to the metal loop, which ensures that the generated magnetic field is approximately uniform. The change of drain current and change of bulk current per micron device width has been measured. The result shows that the difference drain current is about 145 µA for the maximum applied magnetic field. Such changes occur from the applied Lorentz force to push out the carriers from the channel. Based on the drain current difference, the change in effective mobility has been detected up to 4.227%. Furthermore, a detailed investigation reveals that the device behavior is quite different in subthreshold and saturation region. A change of 50.24 µA bulk current has also been measured. Finally, the device has been verified for use as a magnetic sensor with sensitivity 4.084% (29.6 T−1), which is very effective as compared to other previously reported works for a single device.

An experimental investigation on drainage performance of a drain device in a steam generator of PWR

This study evaluates the performance of drain device of a steam dryer in steam generator for PWR through experiments with water and air under ambient temperature and pressure. Two different test sections are designed and tested, one of which is equipped with a single drain pipe (test section I) and the other is equipped with double drain pipes (test section II). For the test section I, various slopes of bottom plate (3.5°–5°) and different numbers of water entrance holes (36–136) are investigated to study their effects on drainage performance of the drain device. For the test section II, only the influence of different entrance holes is studied. In experiments, flow fields in the drain device for different flow rates ranging form 13.8 m3/h to 165.7 m3/h are recorded using a video camera and the corresponding video images are processed by MATLAB to obtain the free liquid surface configuration. The experimental results show that the free liquid surface height of the test section I with single drain pipe is much bigger than that of the test section II with double drain pipes. In addition, the maximum free liquid surface height in the drain tank increases linearly with the increase of flow rate for both test sections while the number of entrance holes has no obvious effect on the maximum free liquid surface height. For the test section I, the bottom plate inclination influences the maximum free liquid surface height and 4° inclination meets the optimized value.

Unilateral neck swelling: A rare case of right internal jugular vein fenestration

Venous anomalies are rare entities in head and neck region. Duplication and fenestration, although rare, are the most commonly seen IJV anomalies. Duplicate IJV bifurcates and drains separately into SCV and reunites as a single channel and drain into SCV in case of fenestration. Duplication or fenestration are rarely symptomatic and usually an incidental finding. We are reporting a rare such case of right IJV fenestration presenting as a diagnostic dilemma of unilateral intermittent neck swelling. The objective of reporting this case was to discuss the presentation and clinical implications of jugular vein anomalies to prevent iatrogenic morbidity or radiological misinterpretations.

Effect of One versus Two Drain Insertion on Postoperative Seroma Formation after Modified Radical Mastectomy

Background: Modified radical mastectomy (MRM) is still one of globally accepted surgical techniques for breast cancer and in some selected patient is the gold standard type of surgery. The most frequent complication of this procedure is seroma under skin flaps or in the axilla as reported as much as 30% in some studies. The use of closed suction drainage system to reduce the incidence of this complication has been routinely accepted by surgeons; however, length of catheter stay and the number of catheters inserted in the wound are still controversial. The present study compares the results of single versus double drain insertion in patients undergoing MRM for breast cancer.Materials and Methods: The study was conducted on 100 women with breast cancer who were candidate for MRM surgery during 2007-2010 referred to Modarres hospital, Tehran, Iran as a randomized group matched controlled trial.Results: There was no significant difference between the two groups in terms of age, BMI, and tumor weight (P=0.406) (Table 1). Similarly, the difference between the two groups was insignificant in tumor size (T) and number of lymph nodes involved (P=0.145). There was no significant difference between the two groups in timing of axillary drain removal (P=0.064). No significant differences were observed between the two groups in mean aspirated fluid (P=0.071) and mean aspirated sera (P=0.484) after removal of drains.Conclusion: This study revealed one drain insertion in MRM surgery is as effective as two drain and probably less morbidity and cost.