Forced expiratory technique, directed cough, and autogenic drainage.

PubMed

Fink, James B

2007-09-01

In health, secretions produced in the respiratory tract are cleared by mucociliary transport, cephalad airflow bias, and cough. In disease, increased secretion viscosity and volume, dyskinesia of the cilia, and ineffective cough combine to reduce secretion clearance, leading to increased risk of infection. In obstructive lung disease these conditions are further complicated by early collapse of airways, due to airway compression, which traps both gas and secretions. Techniques have been developed to optimize expiratory flow and promote airway clearance. Directed cough, forced expiratory technique, active cycle of breathing, and autogenic drainage are all more effective than placebo and comparable in therapeutic effects to postural drainage; they require no special equipment or care-provider assistance for routine use. Researchers have suggested that standard chest physical therapy with active cycle of breathing and forced expiratory technique is more effective than chest physical therapy alone. Evidence-based reviews have suggested that, though successful adoption of techniques such as autogenic drainage may require greater control and training, patients with long-term secretion management problems should be taught as many of these techniques as they can master for adoption in their therapeutic routines.

Palliative percutaneous transhepatic drainage for inoperable obstructive jaundice.

PubMed Central

Baxter-Smith, D. C.; Temple, J. G.; Howarth, F.

1982-01-01

A technique of percutaneous transhepatic drainage under local anaesthesia is described for the relief of intractable pruritus in patients with obstructive jaundice due to inoperable carcinoma. After standard percutaneous transhepatic cholangiography a polyethylene catheter is introduced into one of the large dilated bile ducts and left in situ, thereby establishing external retrograde biliary drainage. The technique has been used successfully in 6 cases with reduction in serum bilirubin levels and relief of pruritus. PMID:6182832

Non-surgical and non-chemical attempts to treat echinococcosis: do they work?

PubMed Central

Tamarozzi, Francesca; Vuitton, Lucine; Brunetti, Enrico; Vuitton, Dominique Angèle; Koch, Stéphane

2014-01-01

Cystic echinococcosis (CE) and alveolar echinococcosis (AE) are chronic, complex and neglected diseases. Their treatment depends on a number of factors related to the lesion, setting and patient. We performed a literature review of curative or palliative non-surgical, non-chemical interventions in CE and AE. In CE, some of these techniques, like radiofrequency thermal ablation (RFA), were shelved after initial attempts, while others, such as High-Intensity Focused Ultrasound, appear promising but are still in a pre-clinical phase. In AE, RFA has never been tested, however, radiotherapy or heavy-ion therapies have been attempted in experimental models. Still, application to humans is questionable. In CE, although prospective clinical studies are still lacking, therapeutic, non-surgical drainage techniques, such as PAIR (puncture, aspiration, injection, re-aspiration) and its derivatives, are now considered a useful option in selected cases. Finally, palliative, non-surgical drainage techniques such as US- or CT-guided percutaneous biliary drainage, centro-parasitic abscesses drainage, or vascular stenting were performed successfully. Recently, endoscopic retrograde cholangiopancreatography (ERCP)-associated techniques have become increasingly used to manage biliary fistulas in CE and biliary obstructions in AE. Development of pre-clinical animal models would allow testing for AE techniques developed for other indications, e.g. cancer. Prospective trials are required to determine the best use of PAIR, and associated procedures, and the indications and techniques of palliative drainage. PMID:25531730

Initial Australasian experience with portal-enteric drainage in simultaneous pancreas-kidney transplantation.

PubMed

Kave, Ben; Yii, Ming; Bell, Roger; Kanellis, John; Scott, David; Saunder, Alan

2010-10-01

Pancreas-kidney transplantation is currently the most effective method to re-establish euglycaemia in insulin-dependent diabetics with associated renal failure. The standard technique employed has been bladder drainage of exocrine secretions coupled with systemic venous drainage ('systemic-bladder' (SB) drainage). The more physiological technique, enteric exocrine with portal venous drainage ('portal-enteric' (PE) drainage), has been utilized sparingly in the past as a result of fears of technical complications. This paper compares the Monash Medical Centre experience with both techniques. A total of 68 simultaneous pancreas-kidney transplantations were performed at Monash Medical Centre from 1991 until 2004. The first 37 received SB drainage. Since March 2001, 27 have received PE drainage. This retrospective study compared the SB group (n= 37) with the PE group (n= 27), with a 2-year follow-up, examining a number of surgical outcomes. Two-year patient (94.3 versus 96.0%), kidney (89.2 versus 85.2%), pancreas (77.9 versus 71.4%) and event-free (73.0 versus 67.7%) survivals were all similar between the SB and PE groups, respectively. Although surgery took longer in PE subjects (4 h : 47 min ± 0:48 versus 5 h : 16 min ± 1:00; P= 0.045), less intraoperative transfusions were required (1.3 ± 1.43 versus 0.52 ± 0.90; P= 0.024). Length of hospital stay and time to insulin independence were similar. Pancreas graft thrombosis rates were similar (10.8% SB versus 7.4% PE, P= 0.497). PE drainage is a safe and viable method for pancreas transplantation, which can be performed with excellent outcomes. An increased rate of complications with PE drainage has not been demonstrated in this series. © 2009 The Authors. ANZ Journal of Surgery © 2009 Royal Australasian College of Surgeons.

40 CFR 112.8 - Spill Prevention, Control, and Countermeasure Plan requirements for onshore facilities (excluding...

Code of Federal Regulations, 2010 CFR

2010-07-01

... drainage from diked storage areas by valves to prevent a discharge into the drainage system or facility... facility drainage systems from undiked areas with a potential for a discharge (such as where piping is... pumps. Whatever techniques you use, you must engineer facility drainage systems to prevent a discharge...

Representing natural and manmade drainage systems in an earth system modeling framework

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Hongyi; Wu, Huan; Huang, Maoyi

Drainage systems can be categorized into natural or geomorphological drainage systems, agricultural drainage systems and urban drainage systems. They interact closely among themselves and with climate and human society, particularly under extreme climate and hydrological events such as floods. This editorial articulates the need to holistically understand and model drainage systems in the context of climate change and human influence, and discusses the requirements and examples of feasible approaches to representing natural and manmade drainage systems in an earth system modeling framework.

[Tentorial Dural Arteriovenous Fistula Successfully Treated with Transvenous Embolization Using a Double Catheterization Technique through Venous Drainage:A Case Report].

PubMed

Yamakawa, Akira; Fujita, Atsushi; Tanaka, Hirotomo; Ikeda, Mitsuru; Morikawa, Masashi; Kohmura, Eiji

2017-07-01

Tentorial dural arteriovenous fistulas(dAVFs)are a rare clinical entity accounting for less than 10% of all intracranial dAVFs. Because these lesions are characterized by high hemorrhagic risk, aggressive treatment should be considered. Although the number of reported cases treated with endovascular transarterial embolization(TAE)using glue has been increasing, little is known about the transvenous approach. Here, we report the case of a patient with a tentorial dAVF who was successfully treated with transvenous embolization(TVE)through venous drainage using a double catheterization technique. A 68-year-old male patient who had a history of left putaminal hemorrhage treated with a craniotomy was diagnosed with a tentorial dAVF on a magnetic resonance angiogram. Because the patient refused another craniotomy for surgical interruption of the dAVF, an endovascular approach was considered. We first attempted to perform TAE with glue, but catheterization into the tortuous meningohypophyseal trunk failed. We then performed a TVE of the venous drainage near the shunt with detachable coils and achieved complete obliteration of the fistula. During coil embolization of the venous drainage, insertion of small coils near the shunt was supported by another anchor coil that was delivered using a double catheterization technique. The method of TVE through venous drainage using a double catheterization technique, which involved placing coils in the fragile drainage vein, was safe and effective in a case of tentorial dAVF. This technique should be considered as another option for the management of complex tentorial dAVFs.

[Drainage variants in reconstructive and restorative operations for high strictures and injuries of the biliary tract].

PubMed

Toskin, K D; Starosek, V N; Grinchesku, A E

1990-10-01

The article deals with the author's views on certain aspects of the problem of reconstructive and restorative surgery of the biliary tract. Original methods are suggested for external drainage (through the inferior surface of the right hepatic lobe in the region of the gallbladder seat and through the round ligament of the liver) in formation of ++hepato-hepatico- and hepaticojejunoanastomoses. Problems of operative techniques in formation of the anastomoses are discussed. Thirty-nine operations have been carried out in the clinic in the recent decade in high strictures and traumas of the biliary tract, 25 were reconstructive and 14 restorative. Postoperative mortality was 28.2% (11 patients). Intoxication and hepatargia associated with cholangiolytic abscesses of the liver were the main causes of death.

Blood loss associated with Ring uncemented total knee replacement: comparison between continuous and intermittent suction drainage.

PubMed Central

Wittmann, F W; Ring, P A

1984-01-01

In a retrospective comparison of blood loss following uncemented total knee replacement, in which either continuous or intermittent suction drainage was used, measured blood loss was significantly greater with continuous drainage. However, a method of calculating actual blood loss demonstrated no significant difference. With intermittent drainage, more blood remains undetected around the knee joint; this technique should therefore be abandoned in favour of continuous suction drainage. PMID:6747978

Innovations and techniques for balloon-enteroscope-assisted endoscopic retrograde cholangiopancreatography in patients with altered gastrointestinal anatomy

PubMed Central

Yamauchi, Hiroshi; Kida, Mitsuhiro; Imaizumi, Hiroshi; Okuwaki, Kosuke; Miyazawa, Shiro; Iwai, Tomohisa; Koizumi, Wasaburo

2015-01-01

Endoscopic retrograde cholangiopancreatography (ERCP) remains challenging in patients who have undergone surgical reconstruction of the intestine. Recently, many studies have reported that balloon-enteroscope-assisted ERCP (BEA-ERCP) is a safe and effective procedure. However, further improvements in outcomes and the development of simplified procedures are required. Percutaneous treatment, Laparoscopy-assisted ERCP, endoscopic ultrasound-guided anterograde intervention, and open surgery are effective treatments. However, treatment should be noninvasive, effective, and safe. We believe that these procedures should be performed only in difficult-to-treat patients because of many potential complications. BEA-ERCP still requires high expertise-level techniques and is far from a routinely performed procedure. Various techniques have been proposed to facilitate scope insertion (insertion with percutaneous transhepatic biliary drainage (PTBD) rendezvous technique, Short type single-balloon enteroscopes with passive bending section, Intraluminal injection of indigo carmine, CO2 inflation guidance), cannulation (PTBD or percutaneous transgallbladder drainage rendezvous technique, Dilation using screw drill, Rendezvous technique combining DBE with a cholangioscope, endoscopic ultrasound-guided rendezvous technique), and treatment (overtube-assisted technique, Short type balloon enteroscopes) during BEA-ERCP. The use of these techniques may allow treatment to be performed by BEA-ERCP in many patients. A standard procedure for ERCP yet to be established for patients with a reconstructed intestine. At present, BEA-ERCP is considered the safest and most effective procedure and is therefore likely to be recommended as first-line treatment. In this article, we discuss the current status of BEA-ERCP in patients with surgically altered gastrointestinal anatomy. PMID:26074685

Lymphatic drainage in renal cell carcinoma: back to the basics.

PubMed

Karmali, Riaz J; Suami, Hiroo; Wood, Christopher G; Karam, Jose A

2014-12-01

Lymphatic drainage in renal cell carcinoma (RCC) is unpredictable, however, basic patterns can be observed in cadaveric and sentinel lymph node mapping studies in patients with RCC. The existence of peripheral lymphovenous communications at the level of the renal vein has been shown in mammals but remains unknown in humans. The sentinel lymph node biopsy technique can be safely applied to map lymphatic drainage patterns in patients with RCC. Further standardisation of sentinel node biopsy techniques is required to improve the clinical significance of mapping studies. Understanding lymphatic drainage in RCC may lead to an evidence-based consensus on the surgical management of retroperitoneal lymph nodes. © 2014 The Authors. BJU International © 2014 BJU International.

Rapid Pore Cranial Drilling With External Ventricular Drainage for Treatment of Intraventricular Hemorrhage: A 36-Year Case Series

PubMed Central

Zhang, Wei; Wei, Lin; Li, Gang; Sun, Jinlong; Jin, Peng; Yang, Jun; Wang, Daokui; Bai, Yunan; Li, Xingang; Fei, Chang; Wang, Chengwei; Wang, Baoan; Pan, Shumao; Du, Jihai; Xie, Bo; Xu, Dongfang; Xin, Changming; Wang, Jihua; Zhang, Qinglin

2015-01-01

This study aimed to describe the technique details of rapid pore cranial drilling with external ventricular drainage and document its clinical outcomes by highlighting the advantages over the traditional and modified cranial drilling technique. Intraventricular hemorrhage is one of the most severe subtypes of hemorrhagic stroke with high mortality. The amount of blood in the ventricles is associated with severity of outcomes, and fast removal of the blood clot is the key to a good prognosis. Between 1977 and 2013, 3773 patients admitted for intraventricular hemorrhage underwent rapid pore cranial drilling drainage. The therapeutic effects and clinical outcomes were retrospectively analyzed. Of these patients, 1049 (27.8%) experienced complete remission, 1788 (47.4%) had improved condition, and 936 (24.8%) died. A total of 3229 (85.6%) patients gained immediate remission. One typical case was illustrated to demonstrate the efficacy of the rapid pore drilling technique. Rapid pore cranial drilling drainage in patients with intraventricular hemorrhage is fast, effective, and provides immediate relief in patients with severe conditions. It could be a better alternative to the conventional drilling approach for treatment of intraventricular hemorrhage. A randomized controlled trial for direct comparison between the rapid pore cranial drilling drainage and conventional drilling technique is in urgent need. PMID:25590642

Rapid Pore Cranial Drilling With External Ventricular Drainage for Treatment of Intraventricular Hemorrhage: A 36-Year Case Series.

PubMed

Zhang, Wei; Wei, Lin; Li, Gang; Sun, Jinlong; Jin, Peng; Yang, Jun; Wang, Daokui; Bai, Yunan; Li, Xingang; Fei, Chang; Wang, Chengwei; Wang, Baoan; Pan, Shumao; Du, Jihai; Xie, Bo; Xu, Dongfang; Xin, Changming; Wang, Jihua; Zhang, Qinglin

2015-06-01

This study aimed to describe the technique details of rapid pore cranial drilling with external ventricular drainage and document its clinical outcomes by highlighting the advantages over the traditional and modified cranial drilling technique. Intraventricular hemorrhage is one of the most severe subtypes of hemorrhagic stroke with high mortality. The amount of blood in the ventricles is associated with severity of outcomes, and fast removal of the blood clot is the key to a good prognosis. Between 1977 and 2013, 3773 patients admitted for intraventricular hemorrhage underwent rapid pore cranial drilling drainage. The therapeutic effects and clinical outcomes were retrospectively analyzed. Of these patients, 1049 (27.8%) experienced complete remission, 1788 (47.4%) had improved condition, and 936 (24.8%) died. A total of 3229 (85.6%) patients gained immediate remission. One typical case was illustrated to demonstrate the efficacy of the rapid pore drilling technique. Rapid pore cranial drilling drainage in patients with intraventricular hemorrhage is fast, effective, and provides immediate relief in patients with severe conditions. It could be a better alternative to the conventional drilling approach for treatment of intraventricular hemorrhage. A randomized controlled trial for direct comparison between the rapid pore cranial drilling drainage and conventional drilling technique is in urgent need.

A Novel Technique of a Transcorneal Suture to Manage an Iris Tuck into the Tube of a Glaucoma Drainage Device.

PubMed

Kataria, Pankaj; Kaushik, Sushmita; Singh, Simar R; Pandav, Surinder S

2016-08-01

Glaucoma drainage devices create an alternative pathway of aqueous drainage from the anterior chamber by channelling aqueous out of the eye through a tube to a subconjunctival bleb or the suprachoroidal space. They may be associated with a number of potential complications including tube malpositioning. This malpositioning may have serious sequelae such as corneal endothelial damage, chronic iritis, tube iris touch, cataract formation, or tube occlusion. Occlusion of the mouth of the tube by the iris impedes aqueous drainage and results in the failure of intraocular pressure (IOP) control. Tube repositioning in cases of occlusion of the mouth of the tube by the iris often involves extensive and potentially complicated surgery requiring tube removal and reinsertion. We describe a new minimally invasive surgical technique for correcting posterior tube malposition resulting in tube occlusion by the iris. The iris had occluded the tube of a Baerveldt prototype glaucoma drainage devices and caused an intractable increased IOP. After our tube sling suture, the tube was free, and the IOP normalized. The procedure entailed no difficult dissection or major surgical intervention. The technique is illustrated by a surgical video. This novel technique is a simple method that relieved the occlusion successfully, and avoided the need to redissect the conjunctiva or shorten the tube.

Portal-endocrine and gastric-exocrine drainage technique of pancreas transplantation provides an easy access for evaluation of pancreatic allograft dysfunction: six-year experience at a single center.

PubMed

Zibari, Gazi B; Fallahzadeh, Mohammad Kazem; Hamidian Jahromi, Alireza; Zakhary, Joseph; Dies, David; Wellman, Greg; Singh, Neeraj; Shokouh-Amiri, Hosein

2014-01-01

The aim of this study is to report our six-year experience with portal-endocrine and gastric-exocrine drainage technique of pancreatic transplantation, which was first developed and implemented at our center in 2007. In this study, the outcomes of all patients at our center who had pancreas transplantation with portal-endocrine and gastric-exocrine drainage technique were evaluated. From October 2007 to November 2013, 38 patients had pancreas transplantation with this technique - 31 simultaneous kidney pancreas and seven pancreas alone. Median duration of follow-up was 3.8 years. One-, three-, and five-year patient and graft survival rates were 94%, 87%, 70% and 83%, 65%, 49%, respectively. For pancreas allograft dysfunction evaluation, 51 upper endoscopies were performed in 14 patients; donor duodenal biopsies were successfully obtained in 45 (88%). We detected nine episodes of acute rejection (eight patients) and seven episodes of cytomegalovirus (CMV) duodenitis (six patients). No patient developed any complication due to upper endoscopy. Portal-endocrine and gastric-exocrine drainage technique of pancreas transplantation provides lifelong easy access to the transplanted duodenum for evaluation of pancreatic allograft dysfunction.

Petrous apex cholesterol granuloma: importance of pedicled nasoseptal flap in addition to silicone T-tube for prevention of occlusion of drainage route in transsphenoidal approach--a technical note.

PubMed

Shibao, Shunsuke; Toda, Masahiro; Tomita, Toshiki; Saito, Katsuya; Ogawa, Kaoru; Kawase, Takeshi; Yoshida, Kazunari

2015-01-01

Recently, petrous apex cholesterol granulomas (CGs) have been treated via the endoscopic endonasal transsphenoidal approach (EEA) using a silicone tube, to prevent drainage route occlusion. Occlusion of the drainage route has led to problems with recurrence. The aim of this report is to describe the use of a surgical technique to prevent drainage route occlusion. In surgical technique, the posterolateral wall of the sphenoid sinus was opened by EEA. After cyst debridement, a vascularized nasoseptal flap with a width of approximately 4 cm was inserted into the lumen with a silicone T-tube with a diameter of 7 mm. This technique was used in two patients: the first patient during the second operation after recurrence following occlusion of the drainage route, and the second patient during the first operation. Opening of the cyst wall was confirmed endoscopically in both patients 12-24 months after surgery, even after removal of the T-tube. In conclusion, the use of a pedicled nasoseptal flap with a silicone tube is useful to prevent CG recurrence, by paranasal cavitization of the cystic cavity.

[Circular transhepatic drainage as a palliative surgical measure in central bile duct obstruction].

PubMed

Neugebauer, W; Durst, J; Koslowski, L

1979-10-01

A transhepatic drainage tube was used in 27 patients suffering from echinococcus alveolaris of the liver of malignant process of the portal fissure from 1967 to 1978. If an hepatocholangioenterostomy is not possible, another surgical palliative procedure is necessary for drainage of the bile. The transhepatic drainage tube is a simple palliative method. The technique of this procedure, the indications, the possible complications, and the advantages are reported.

Technique for predicting ground-water discharge to surface coal mines and resulting changes in head

USGS Publications Warehouse

Weiss, L.S.; Galloway, D.L.; Ishii, Audrey L.

1986-01-01

Changes in seepage flux and head (groundwater level) from groundwater drainage into a surface coal mine can be predicted by a technique that considers drainage from the unsaturated zone. The user applies site-specific data to precalculated head and seepage-flux profiles. Groundwater flow through hypothetical aquifer cross sections was simulated using the U.S. Geological Survey finite-difference model, VS2D, which considers variably saturated two-dimensional flow. Conceptual models considered were (1) drainage to a first cut, and (2) drainage to multiple cuts, which includes drainage effects of an area surface mine. Dimensionless head and seepage flux profiles from 246 simulations are presented. Step-by-step instructions and examples are presented. Users are required to know aquifer characteristics and to estimate size and timing of the mine operation at a proposed site. Calculated groundwater drainage to the mine is from one excavated face only. First cut considers confined and unconfined aquifers of a wide range of permeabilities; multiple cuts considers unconfined aquifers of higher permeabilities only. The technique, developed for Illinois coal-mining regions that use area surface mining and evaluated with an actual field example, will be useful in assessing potential hydrologic impacts of mining. Application is limited to hydrogeologic settings and mine operations similar to those considered. Fracture flow, recharge, and leakage are nor considered. (USGS)

Impact of an aseptic procedure for breaking the integrity of the urinary drainage system on the development of catheter-associated urinary tract infections in the intensive care unit.

PubMed

Powers, Jan

2016-12-01

Catheter associated urinary tract infections (CAUTI) are a common complication in the hospital, especially in intensive care units (ICU). These infections are directly linked to the use of an indwelling urinary catheter. One commonly identified factor related to the development of CAUTI has been thought to be violating the integrity of the closed drainage system. However, a paucity of research exists to support or refute this practice. The primary purpose of this observational study was to assess if there is a relationship between CAUTI incidence and breaking the closed drainage system using an aseptic procedure. A process improvement effort was developed to ensure an aseptic technique was utilised when there was a need to break the integrity of the urinary drainage system. Because this was a new practice and not supported by the Centres for Disease Control (CDC) recommendations, this change in practice was evaluated as an observational study. In an eight month period there were 53 documented breaks in the urinary drainage system. There were 28 total cases of CAUTI overall during this same time period. Only four patients with a system break developed a CAUTI (7.5%). In almost 93% of the patients where aseptic technique was used for breaks in the drainage system, there was no occurrence of CAUTI. A follow-up evaluation was performed after a year of this practice in three adult ICUs. During this three month evaluation period, there were 47 documented cases of breaking this system using aseptic technique. Of the patients who had a documented break in their drainage system, none developed subsequent CAUTIs. One commonly identified factor related to the development of CAUTI has been thought to be violating the integrity of the closed drainage system. However, a paucity of research exists to support or refute this practice. This observational study found that utilising an aseptic technique to break the integrity system did not result in an associated increase in CAUTI. Copyright © 2016 Elsevier Ltd. All rights reserved.

Mine Water Treatment in Hongai Coal Mines

NASA Astrophysics Data System (ADS)

Dang, Phuong Thao; Dang, Vu Chi

2018-03-01

Acid mine drainage (AMD) is recognized as one of the most serious environmental problem associated with mining industry. Acid water, also known as acid mine drainage forms when iron sulfide minerals found in the rock of coal seams are exposed to oxidizing conditions in coal mining. Until 2009, mine drainage in Hongai coal mines was not treated, leading to harmful effects on humans, animals and aquatic ecosystem. This report has examined acid mine drainage problem and techniques for acid mine drainage treatment in Hongai coal mines. In addition, selection and criteria for the design of the treatment systems have been presented.

CT fluoroscopy-guided percutaneous drainage: comparison of the one step and the Seldinger techniques.

PubMed

Kajiwara, Kenji; Yamagami, Takuji; Ishikawa, Masaki; Yoshimatsu, Rika; Baba, Yasutaka; Nakamura, Yuko; Fukumoto, Wataru; Awai, Kazuo

2017-06-01

To evaluate the one step technique compared with the Seldinger technique in computed tomography (CT) fluoroscopy-guided percutaneous drainage of abdominal and pelvic abscess. Seventy-six consecutive patients (49 men, 27 women; mean age 63.5 years, range 19-87 years) with abdominal and pelvic abscess were included in this study. Drainages were performed with the one step (n = 46) and with the Seldinger (n = 48) technique between September 2012 and June 2014. The technical success and clinical success rates were 95.8% and 93.5%, respectively, for the one step group, and 97.8% and 95.7%, respectively, for the Seldinger group. The mean procedure time was significantly shorter with the one step than with the Seldinger method (15.0 ± 4.3 min, range 10-29 min vs. 21.0 ± 9.5 min, range 13-54 min, p < .01). The mean abscess size and depth were 73.4 ± 44.0 mm and 42.5 ± 19.3 mm, respectively, in the one step group, and 61.0 ± 22.8 mm and 35.0 ± 20.7 mm in the Seldinger group. The one step technique was easier and faster than the Seldinger technique. The effectiveness of both techniques was similar for the CT fluoroscopy-guided percutaneous drainage of abdominal and pelvic abscess.

The evolution of anterior sector venous drainage in right lobe living donor liver transplantation: does one technique fit all?

PubMed Central

Tokat, Yaman

2016-01-01

In living donor liver transplantation (LDLT), an adequate hepatic venous outflow constitutes one of the basic principles of a technically successful procedure. The issue of whether the anterior sector (AS) of the right lobe (RL) graft should or should not be routinely drained has been controversial. The aim of this 10-year, single-center, retrospective cohort study was to review the evolution of our hepatic venous outflow reconstruction technique in RL grafts and evaluate the impact of routine AS drainage strategy on the outcome. The study group consisted of 582 primary RL LDLT performed between July 2004 and December 2014. The cases were divided into 3 consecutive periods with different AS venous outflow reconstruction techniques, which included middle hepatic vein (MHV) drainage in Era 1 (n=119), a more selective AS drainage with cryopreserved homologous grafts in Era 2 (n=391), and routine segment 5 and/or 8 oriented AS drainage with synthetic grafts in Era 3 (n=72). Intraoperative portal flow measurement with routine splenic artery ligation (SAL) technique (in RL grafts with a portal flow of ≥ 250 mL/min/100 g liver tissue) was added later in Era 3. These 3 groups were compared in terms of recipient and donor demographics, surgical characteristics and short-term outcome. The rate of AS venous drainage varied from 58.8% in Era 1 and 35.0% in Era 2 to 73.6% in Era 3 (P<0.001). Perioperative mortality rate of recipients significantly decreased over the years (15.1% in Era 1 and 8.7% in Era 2 vs. 2.8% in Era 3, P=0.01). After the addition of SAL technique in the 45 cases, there was only 1 graft loss and no perioperative mortality. One-year recipient survival rate was also significantly higher in Era 3 (79.6% in Era 1 and 86.1% in Era 2 vs. 92.1% in Era 3, P=0.002). Routine AS drainage via segment 5 and/or 8 veins using synthetic grafts is a technique to fit all RL grafts in LDLT. Addition of SAL effectively prevents early graft dysfunction and significantly improves the outcome. PMID:27115010

Ultrasound-guided Pleural Effusion Drainage With a Small Catheter Using the Single-step Trocar or Modified Seldinger Technique.

PubMed

Abusedera, Mohammad; Alkady, Ola

2016-04-01

Studies have shown that small-catheter pleural effusion drainage is safe and has a lower complication rate. Our objective was to evaluate the outcomes and the safety of the single-step trocar or the modified Seldinger technique. A total of 124 patients (83 men and 41 women), with mean age of 46±18 years and mean duration of drainage 5.3±2 days, were include in the study. The trocar technique was attempted in 201 (86.5%) cases, and the modified Seldinger technique was used in 38 (16.5%) cases. Technical success was obtained in 96% for the trocar technique and in 100% for the modified Seldinger technique. The procedure time for the trocar and the modified Seldinger techniques was approximately 7 and 12 minutes, respectively (P-value=0.02). The overall success rate was 72.9%. The success rate was highest for massive transudative effusions (98%) followed by malignant effusions (87%), and it was least for parapneumonic effusion/empyema (72 %). Pneumothorax occurred in 10.5% (n=4) for modified Seldinger versus 0.5% (n=1) (P=0.12) for trocar, whereas bleeding occurred in 0% for modified Seldinger and in 1% (n=2) for trocar (P=0.04). The single-step trocar technique was technically unsuccessful in 8 cases (7 had empyema with narrow intercostal spaces and one had kyphoscoliosis); technical success was achieved by using the modified Seldinger. Ultrasound-guided pleural effusion drainage by catheter insertion is a safe and effective procedure. The success rate is low when the effusion is loculated and septated. Both the trocar and the modified Seldinger techniques can be used. The trocar technique is faster and easier.

A “Train-Track” Technique in Anatomic Reconstruction of SVC Bifurcation Complicated by Cardiac Tamponade: An Introspection

DOE Office of Scientific and Technical Information (OSTI.GOV)

Karuppasamy, Karunakaravel, E-mail: karuppk@ccf.org; Al-Natour, Mohammed, E-mail: mnatour85@msn.com; Gurajala, Ram Kishore, E-mail: gurajar@ccf.org

This report describes a stenting technique used to anatomically reconstruct superior vena cava (SVC) bifurcation in a patient with benign SVC syndrome. After recanalizing the SVC bifurcation, we exchanged two 0.035-in. wires for two 0.018-in. wires, deployed the SVC stent over these two wires (“train-track” technique), and stented each innominate vein over one wire. However, our decisions to recanalize both innominate veins, use the “buddy-wire” technique for SVC dilation, and dilate the SVC to 16 mm before stent deployment likely contributed to SVC tear, which was managed by resuscitation, SVC stent placement, and pericardial drainage. Here, we describe the steps ofmore » the train-track technique, which can be adopted to reconstruct other bifurcations; we also discuss the controversial aspects of this case.« less

A New CT-Guided Modified Trocar Technique for Drainage of Difficult Locations Abscesses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tyng, Chiang J., E-mail: chiangjengtyng@gmail.com; Amoedo, Maurício K.; Bohrer, Yves

PurposeComputed tomography (CT) is commonly used to guide drainage of deep-seated abdominal fluid collections. However, in some cases, these collections seem to be inaccessible due to surrounding organs or their being in difficult locations. The aim of this study is to describe a modified Trocar technique to drain collections in difficult locations, especially those in the subphrenic space, without passing through intervening organs.Materials and MethodsThis retrospective case series study describes seven inpatients who underwent CT-guided drainage using a modified Trocar technique for abscesses that are difficult to access percutaneously. All patients provided written informed consent prior to the procedure. Aftermore » placement of a 12–14F catheter inside the peritoneum, the Trocar stylet was removed so that the tip of the catheter became blunt and flexible to avoid injury to organs and structures in the catheter route, and the catheter was slowly advanced towards the collection using CT guidance and tactile sensation. After reaching the target, the stylet was reintroduced to enter the abscess wall.ResultsAll procedures were performed using an anterior abdominal wall access with adequate catheter positioning and resulted in clinical status improvement in the days after the drainage. No complications related to the procedure were identified in any of the patients.ConclusionsThe modified Trocar technique for percutaneous CT-guided drainage of abdominal abscesses may be feasible for lesions that are difficult to access with conventional methods.« less

Comparing morphologies of drainage basins on Mars and Earth using integral-geometry and neural maps

NASA Technical Reports Server (NTRS)

Stepinski, T. F.; Coradetti, S.

2004-01-01

We compare morphologies of drainage basins on Mars and Earth in order to confine the formation process of Martian valley networks. Basins on both planets are computationally extracted from digital topography. Integral-geometry methods are used to represent each basin by a circularity function that encapsulates its internal structure. The shape of such a function is an indicator of the style of fluvial erosion. We use the self-organizing map technique to construct a similarity graph for all basins. The graph reveals systematic differences between morphologies of basins on the two planets. This dichotomy indicates that terrestrial and Martian surfaces were eroded differently. We argue that morphologies of Martian basins are incompatible with runoff from sustained, homogeneous rainfall. Fluvial environments compatible with observed morphologies are discussed. We also construct a similarity graph based on the comparison of basins hypsometric curves to demonstrate that hypsometry is incapable of discriminating between terrestrial and Martian basins. INDEX TERMS: 1824 Hydrology: Geomorphology (1625); 1886 Hydrology: Weathering (1625); 5415 Planetology: Solid Surface Planets: Erosion and weathering; 6225 Planetology: Solar System Objects Mars. Citation: Stepinski, T. F., and S. Coradetti (2004), Comparing morphologies of drainage basins on Mars and Earth using integral-ge

Power-law tail probabilities of drainage areas in river basins

USGS Publications Warehouse

Veitzer, S.A.; Troutman, B.M.; Gupta, V.K.

2003-01-01

The significance of power-law tail probabilities of drainage areas in river basins was discussed. The convergence to a power law was not observed for all underlying distributions, but for a large class of statistical distributions with specific limiting properties. The article also discussed about the scaling properties of topologic and geometric network properties in river basins.

Intermediate-term and long-term outcome of piggyback drainage: connecting glaucoma drainage device to a device in-situ for improved intraocular pressure control.

PubMed

Dervan, Edward; Lee, Edward; Giubilato, Antonio; Khanam, Tina; Maghsoudlou, Panayiotis; Morgan, William H

2017-11-01

This study provides results of a treatment option for patients with failed primary glaucoma drainage device. The study aimed to describe and evaluate the long-term intraocular pressure control and complications of a new technique joining a second glaucoma drainage device directly to an existing glaucoma drainage device termed 'piggyback drainage'. This is a retrospective, interventional cohort study. Eighteen eyes of 17 patients who underwent piggyback drainage between 2004 and 2013 inclusive have been studied. All patients had prior glaucoma drainage device with uncontrolled intraocular pressure. The piggyback technique involved suturing a Baerveldt (250 or 350 mm) or Molteno3 glaucoma drainage device to an unused scleral quadrant and connecting the silicone tube to the primary plate bleb. Failure of intraocular pressure control defined as an intraocular pressure greater than 21 mmHg on maximal therapy on two separate occasions or further intervention to control intraocular pressure. The intraocular pressure was controlled in seven eyes (39%) at last follow-up with a mean follow-up time of 74.2 months. The mean preoperative intraocular pressure was 27.1 mmHg (95% confidence interval 23.8-30.3) compared with 18.4 mmHg (95% confidence interval 13.9-22.8) at last follow-up. The mean time to failure was 57.1 months (95% confidence interval 32.2-82), and the mean time to further surgery was 72.3 months (95% confidence interval 49.9-94.7). Lower preoperative intraocular pressure was associated with longer duration of intraocular pressure control (P = 0.048). If the intraocular pressure was controlled over 2 years, it continued to be controlled over the long term. Two eyes (11%) experienced corneal decompensation. Piggyback drainage represents a viable surgical alternative for the treatment of patients with severe glaucoma with failing primary glaucoma drainage device, particularly in those at high risk of corneal decompensation. © 2017 Royal Australian and New Zealand College of Ophthalmologists.

An integrated approach to the remote sensing of floating ice

NASA Technical Reports Server (NTRS)

Campbell, W. J.; Ramseier, R. O.; Weeks, W. F.; Gloersen, P.

1976-01-01

Review article on remote sensing applications to glaciology. Ice parameters sensed include: ice cover vs open water, ice thickness, distribution and morphology of ice formations, vertical resolution of ice thickness, ice salinity (percolation and drainage of brine; flushing of ice body with fresh water), first-year ice and multiyear ice, ice growth rate and surface heat flux, divergence of ice packs, snow cover masking ice, behavior of ice shelves, icebergs, lake ice and river ice; time changes. Sensing techniques discussed include: satellite photographic surveys, thermal IR, passive and active microwave studies, microwave radiometry, microwave scatterometry, side-looking radar, and synthetic aperture radar. Remote sensing of large aquatic mammals and operational ice forecasting are also discussed.

Unique usage of a partially covered metal stent for drainage of a pancreatic pseudocyst via endosonography-guided transcystgastrostomy.

PubMed

Nici, Anthony J; Hussain, Syed A; Kim, Sang H; Mehta, Preeti

2012-05-01

Pancreatic pseudocysts are frequent complications of pancreatitis episodes. The current therapeutic modalities for drainage of pancreatic pseudocysts include surgical, percutaneous, and endoscopic drainage modalities. Endosonography-assisted endoscopic drainage of these pseudocysts with the placement of multiple plastic or fully covered self-expanding biliary metal stents is becoming more commonly carried out. The present case report discusses the unique and successful drainage of a pancreatic pseudocyst with the placement of a partially covered self-expanding metal stent. © 2012 The Authors. Digestive Endoscopy © 2012 Japan Gastroenterological Endoscopy Society.

Ureteroscopic holmium laser cutting for inadvertently sutured drainage tube (report of five cases).

PubMed

Gao, Xu; Lu, Xin; Ren, Shancheng; Xu, Chuanliang; Sun, Yinghao

2008-07-01

The aim of this paper is to report a simple solution for inadvertently sutured drainage tube after urological surgery and discuss the different managements according to different types of this embarrassing complication. From September 2001 to January 2007, five inadvertently sutured drainage tubes were treated with ureteroscopic holmium laser cutting for the suture. All drainage tubes were removed after the operation without other complications. Holmium laser cutting via ureteroscope is a simple solution for the embarrassing problem of inadvertently sutured drainage tube. It can save the patient from undergoing another open surgery.

Techniques for estimating flood peak discharges for unregulated streams and streams regulated by small floodwater retarding structures in Oklahoma

USGS Publications Warehouse

Tortorelli, R.L.; Bergman, D.L.

1985-01-01

Statewide regression relations for Oklahoma were determined for estimating peak discharge of floods for selected recurrence intervals from 2 to 500 years. The independent variables required for estimating flood discharge for rural streams are contributing drainage area and mean annual precipitation. Main-channel slope, a variable used in previous reports, was found to contribute very little to the accuracy of the relations and was not used. The regression equations are applicable for watersheds with drainage areas less than 2,500 square miles that are not significantly affected by regulation from manmade works. These relations are presented in graphical form for easy application. Limitations on the use of the regression relations and the reliability of regression estimates for rural unregulated streams are discussed. Basin and climatic characteristics, log-Pearson Type III statistics and the flood-frequency relations for 226 gaging stations in Oklahoma and adjacent states are presented. Regression relations are investigated for estimating flood magnitude and frequency for watersheds affected by regulation from small FRS (floodwater retarding structures) built by the U.S. Soil Conservation Service in their watershed protection and flood prevention program. Gaging-station data from nine FRS regulated sites in Oklahoma and one FRS regulated site in Kansas are used. For sites regulated by FRS, an adjustment of the statewide rural regression relations can be used to estimate flood magnitude and frequency. The statewide regression equations are used by substituting the drainage area below the FRS, or drainage area that represents the percent of the basin unregulated, in the contributing drainage area parameter to obtain flood-frequency estimates. Flood-frequency curves and flow-duration curves are presented for five gaged sites to illustrate the effects of FRS regulation on peak discharge.

Outcome of percutaneous continuous drainage of psoas abscess: A clinically guided technique.

PubMed

Dave, Bharat R; Kurupati, Ranganatha Babu; Shah, Dipak; Degulamadi, Devanand; Borgohain, Nitu; Krishnan, Ajay

2014-01-01

Percutaneous aspiration of abscesses under ultrasonography (USG) and computer tomography (CT) scan has been well described. With recurrence rate reported as high as 66%. The open drainage and percutaneous continuous drainage (PCD) has reduced the recurrence rate. The disadvantage of PCD under CT is radiation hazard and problems of asepsis. Hence a technique of clinically guided percutaneous continuous drainage of the psoas abscess without real-time imaging overcomes these problems. We describe clinically guided PCD of psoas abscess and its outcome. Twenty-nine patients with dorsolumbar spondylodiscitis without gross neural deficit with psoas abscess of size >5 cm were selected for PCD. It was done as a day care procedure under local anesthesia. Sequentially, aspiration followed by guide pin-guided trocar and catheter insertion was done without image guidance. Culture sensitivity was done and chemotherapy initiated and catheter kept till the drainage was <10 ml for 48 hours. Outcome assessment was done with relief of pain, successful abscess drainage and ODI (Oswestry Disability Index) score at 2 years. PCD was successful in all cases. Back and radicular pain improved in all cases. Average procedure time was 24.30 minutes, drain output was 234.40 ml, and the drainage duration was 7.90 days. One patient required surgical stabilisation due to progression of the spondylodiscitis resulting in instability inspite of successful drainage of abscess. Problems with the procedure were noticed in six patients. Multiple attempts (n = 2), persistent discharge (n = 1) for 2 weeks, blocked catheter (n = 2) and catheter pull out (n = 1) occurred with no effect on the outcome. The average ODI score improved from 62.47 to 5.51 at 2 years. Clinically guided PCD is an efficient, safe and easy procedure in drainage of psoas abscess.

Endoscopic ultrasonography guided drainage: Summary of consortium meeting, May 21, 2012, San Diego, California

PubMed Central

Kahaleh, Michel; Artifon, Everson LA; Perez-Miranda, Manuel; Gaidhane, Monica; Rondon, Carlos; Itoi, Takao; Giovannini, Marc

2015-01-01

Endoscopic retrograde cholangiopancreatography (ERCP) is the preferred procedure for biliary and pancreatic drainage. While ERCP is successful in about 95% of cases, a small subset of cases are unsuccessful due to altered anatomy, peri-ampullary pathology, or malignant obstruction. Endoscopic ultrasound-guided drainage is a promising technique for biliary, pancreatic and recently gallbladder decompression, which provides multiple advantages over percutaneous or surgical biliary drainage. Multiple retrospective and some prospective studies have shown endoscopic ultrasound-guided drainage to be safe and effective. Based on the currently reported literature, regardless of the approach, the cumulative success rate is 84%-93% with an overall complication rate of 16%-35%. endoscopic ultrasound-guided drainage seems a viable therapeutic modality for failed conventional drainage when performed by highly skilled advanced endoscopists at tertiary centers with expertise in both echo-endoscopy and therapeutic endoscopy PMID:25624708

Non-surgical biliary drainage - technique, indications and results.

PubMed

Riemann, J F; Lux, G; Rösch, W; Beickert-Sterba, A

1981-07-01

Nonsurgical biliary drainage offers a therapeutic alternative in the palliation of malignant obstructive jaundice. Two basic approaches are available. The percutaneous transhepatic method can be employed either for external drainage or for the placement of an internal endoprosthesis. In the case of the transduodenal, transpapillary approach, either a pigtail catheter can be placed, after prior papillotomy, or - with or without the need to split the papillar - a nasobiliary drainage tube can be introduced. Successful drainage was achieved in 67 patients. In the majority of cases, external drainage was performed as a palliative measure in inoperable carcinoma of the biliodigestive system. In addition, however, pre-operative temporary drainage was also carried out to reduce the risks of surgery in patients with severe obstructive jaundice. The complication rate was low. Apart from biliary peritonitis, cholangitis and minor bleeds were observed. The rate of failure for technical reasons was a relatively low 10%.

GIS based quantitative morphometric analysis and its consequences: a case study from Shanur River Basin, Maharashtra India

NASA Astrophysics Data System (ADS)

Pande, Chaitanya B.; Moharir, Kanak

2017-05-01

A morphometric analysis of Shanur basin has been carried out using geoprocessing techniques in GIS. These techniques are found relevant for the extraction of river basin and its drainage networks. The extracted drainage network was classified according to Strahler's system of classification and it reveals that the terrain exhibits dendritic to sub-dendritic drainage pattern. Hence, from the study, it is concluded that remote sensing data (SRTM-DEM data of 30 m resolution) coupled with geoprocessing techniques prove to be a competent tool used in morphometric analysis and evaluation of linear, slope, areal and relief aspects of morphometric parameters. The combined outcomes have established the topographical and even recent developmental situations in basin. It will also change the setup of the region. It therefore needs to analyze high level parameters of drainage and environment for suitable planning and management of water resource developmental plan and land resource development plan. The Shanur drainage basin is sprawled over an area of 281.33 km2. The slope of the basin varies from 1 to 10 %, and the slope variation is chiefly controlled by the local geology and erosion cycles. The main stream length ratio of the basin is 14.92 indicating that the study area is elongated with moderate relief and steep slopes. The morphometric parameters of the stream have been analyzed and calculated by applying standard methods and techniques viz. Horton (Trans Am Geophys Union 13:350-361, 1945), Miller (A quantitative geomorphologic study of drainage basin characteristics in the clinch mountain area, Virginia and Tennessee Columbia University, Department of Geology, Technical Report, No. 3, Contract N6 ONR 271-300, 1953), and Strahler (Handbook of applied hydrology, McGraw Hill Book Company, New York, 1964). GIS based on analysis of all morphometric parameters and the erosional development of the area by the streams has been progressed well beyond maturity and lithology is an influence in the drainage development. These studies are very useful for planning of rainwater harvesting and watershed management.

Bone Symposium 󈨟 Held in Portland Oregon, on 17-20 July 1991

DTIC Science & Technology

1992-03-01

removed. Persistent drainage and/or sinus tract(s) are common. Multiple species of bacteria are usually isolated from biopsies of infected granulations...patients even years of intermittent drainage . The possibility of attenuating the infection is reduced when the integrity of the soft tissue surrounding...successful transfers had persistent drainage . Only 12 * patients walked without assistive devices in followup.51 The advantage of the Ilizarov technique is

Noninvasive Intracranial Pressure Monitoring Using Advanced Machine Learning Techniques

DTIC Science & Technology

2013-11-01

drainage requiring removal to prevent infection or to allow computed tomography scan. 3. If clinicians had the ability to predict near-future ICP... drainage of cerebrospinal fluid from the ventricles; however, ICP readings are only accurate when the external drainage system is clamped. ICP clamping... craniotomy for hemorrhage evacuation or a craniectomy for treatment of cerebral edema. Overall in-hospital mortality was 19.4%. Eight hundred and ninety

Image-Guided Transvesicular Drainage of Pelvic Fluid Collections: A Safe and Effective Alternative Approach.

PubMed

Ayyagari, Raj R; Yeh, Cliff; Arici, Melih; Mojibian, Hamid; Reiner, Eric; Pollak, Jeffrey S

2016-05-01

To evaluate the safety and efficacy of percutaneous transvesicular drainage of pathologic pelvic fluid collections, a series of 15 patients who underwent 16 transvesicular drainage catheter placements was retrospectively reviewed. All patients had collections suspicious for infection that were posterior to the bladder or superior to the bladder behind loops of bowel, and were otherwise inaccessible. All 15 collections were percutaneously accessed via the bladder with standard drainage catheters. All collections resolved completely with no complications. Percutaneous transvesicular drainage was a safe and effective technique in this series, and can be considered when no direct percutaneous access routes are available. Copyright © 2016 SIR. Published by Elsevier Inc. All rights reserved.

[Nonsurgical therapy of abdominal and retroperitoneal abscesses].

PubMed

Reuss, J A; Seitz, K

1987-06-01

From 1976 to March 1987 intraabdominal or retroperitoneal abscesses were confirmed by ultrasound in 40 patients. 13 patients had surgical drainage with zero-mortality. 3 of 27 patients were treated with antibiotics (only systemically). 24 patients were treated by percutaneous catheter drainage or needle aspiration. Elective cholecystectomy was performed later in 3 patients. Nonsurgical treatment was successful in 22/27 cases. 3 patients died despite percutaneous drainage. Failure of percutaneous drainage required surgical intervention in 3 patients. The considerably poorer primary condition of the patients receiving nonsurgical treatment allows no comparison with the surgical group. Advantages of percutaneous drainage and needle aspiration are a high success rate and low mortality. These techniques can be used even in critically ill persons.

Technique for estimating the magnitude and frequency of floods in Texas.

DOT National Transportation Integrated Search

1977-01-01

Drainage area, slope, and mean annual precipitation were the only : factors that were statistically significant at the 95-percent confidence : level when the characteristics of the drainage basins were used as independent variables in a multiple-regr...

Discussion on Construction Technology of Prestressed Reinforced Concrete Pipeline of Municipal Water Supply and Drainage

NASA Astrophysics Data System (ADS)

Li, Chunyan

2017-11-01

Prestressed reinforced concrete pipe has the advantages of good bending resistance, good anti-corrosion, anti-seepage, low price and so on. It is very common in municipal water supply and drainage engineering. This paper mainly explore the analyze the construction technology of the prestressed reinforced concrete pipe in municipal water supply and drainage engineering.

A Tale of 2 Techniques: Preoperative Biliary Drainage and Routine Surgical Drainage with Pancreaticoduodenectomy.

PubMed

Iskandar, Mazen E; Wayne, Michael G; Steele, Justin G; Cooperman, Avram M

2018-02-01

Preoperative drainage of an obstructed biliary tree before pancreaticoduodenal resection (PDR) and placement of intraabdominal drains following pancreatic resection have been suggested to be both unnecessary and associated with a higher complication rate. The evidence for and against that practice is presented and analyzed to highlight its risks and benefits. A selective approach on an individual basis for preoperative biliary decompression is advocated, based on multiple factors. Additionally, the evidence for routine use of surgical drains after PDR is critically reviewed and the rationale for routine drainage is made. Copyright © 2017 Elsevier Inc. All rights reserved.

Matthew Jones House: Historic Maintenance and Repair Manual

DTIC Science & Technology

2014-08-01

either have to budget money to repair basement doors or in- stall a drainage system to diverge water away from the structure before they begin to...accomplished either through grading the soil, installing a French drainage system , or combining both techniques. French drains are primarily used to...soil drainage system are promoting the deterioration of the base of the house as a direct result of water splashing off the gravel (Figure 48), and

[Manual airway clearance techniques in adults and adolescents: What level of evidence?

PubMed

Cabillic, Michel; Gouilly, Pascal; Reychler, Gregory

2016-04-13

The aim of this systematic literature review was to grade the levels of evidence of the most widely used manual airway clearance techniques. A literature search was conducted over the period 1995-2014 from the Medline, PEDro, ScienceDirect, Cochrane Library, REEDOC and kinedoc databases, with the following keywords: "postural drainage", "manual vibrations", "manual chest percussion", "directed cough", "increased expiratory flow", "ELTGOL", "autogenic drainage" and "active cycle of breathing technique". Two-hundred and fifty-six articles were identified. After removing duplicates and reading the titles and abstracts, 63 articles were selected, including 9 systematic reviews. This work highlights the lack of useful scientific data and the difficulty of determining levels of evidence for manual airway clearance techniques. Techniques were assessed principally with patients with sputum production (cystic fibrosis, DDB, COPD, etc.). It also shows the limited pertinence of outcome measures to quantify congestion and hence the efficacy of airway clearance techniques. The 1994 consensus conference summary table classifying airway clearance techniques according to physical mechanism provides an interesting tool for assessment, grouping together techniques having identical mechanisms of action. From the findings of the present systematic review, it appears that only ELTGOL, autogenic drainage and ACBT present levels of evidence "B". All other techniques have lower levels of evidence. II. Copyright © 2016. Published by Elsevier Masson SAS.

Malignant biliary disease: percutaneous interventions.

PubMed

Morgan, R A; Adam, A N

2001-09-01

Interventional radiologists have an important role in the management of patients with malignant biliary obstruction. This article describes the techniques for percutaneous biliary drainage, insertion of biliary endoprostheses, and the management of occluded biliary endoprostheses. Most procedures are performed by using fluoroscopic guidance alone. Ultrasound is also a useful modality for guiding biliary drainage, particularly drainage of the left biliary ducts. Patients should be treated by internal drainage if possible. Metallic endoprostheses can be inserted at the time of the initial biliary drainage procedure. Plastic tubes should be inserted a few days after biliary drainage because of their relatively large size compared with metallic stents. Occluded plastic stents should be replaced. Blocked metallic stents should be treated either by placement of additional overlapping metallic stents or by placement of plastic stents within the metallic stent lumen. Copyright 2001 by W.B. Saunders Company

Glaucoma in modified osteo-odonto-keratoprosthesis eyes: role of additional stage 1A and Ahmed glaucoma drainage device-technique and timing.

PubMed

Iyer, Geetha; Srinivasan, Bhaskar; Agarwal, Shweta; Shetty, Roshni; Krishnamoorthy, Sripriya; Balekudaru, Shantha; Vijaya, Lingam

2015-03-01

To report the technique, timing, and outcomes of the Ahmed glaucoma drainage device in eyes with the modified osteo-odonto-keratoprosthesis (MOOKP) and the role of an additional stage 1A to the Rome-Vienna protocol. Retrospective interventional case series. Case records of 22 eyes of 20 patients with high intraocular pressure at various stages of the MOOKP procedure performed in 85 eyes of 82 patients were studied. Stage 1A, which includes total iridodialysis, intracapsular cataract extraction, and anterior vitrectomy, was done in all eyes as the primary stage. Seventeen Ahmed glaucoma drainage devices were implanted in 15 eyes of 14 patients (chemical injury in 9 [10 eyes] and Stevens-Johnson syndrome in 5 patients). Implantation was performed during and after stage 1A in 2 and 7 eyes, respectively, after stage 1B+1C in 1 eye, and after stage 2 in 6 eyes. Eleven of 15 eyes (73.3%) remained stable with adequate control of intraocular pressure over a mean follow-up period of 33.68 months (1-90 months). Complications related to the drainage device were hypotony in 1 eye and vitreous block of the tube in 1 eye. It is ideal to place the Ahmed glaucoma drainage device prior to the mucosal graft when the anatomy of the ocular surface is least altered with best outcomes. The technique of placement of the drainage device during the various stages of the MOOKP procedure has been described. The intraocular pressure stabilized in three quarters of the eyes with pre-existing glaucoma. Copyright © 2015 Elsevier Inc. All rights reserved.

Measure Guideline: Guidance on Taped Insulating Sheathing Drainage Planes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Grin, A.; Lstiburek, J.

This guide provides information and recommendations to the following groups: insulation contractors; general contractors; builders; home remodelers; mechanical contractors; and homeowners, as a guide to the work that needs to be done. The order of work completed during home construction and retrofit improvements is important. Health and safety issues must be addressed first and are more important than durability issues. And durability issues are more important than saving energy. Not all techniques can apply to all houses. Special conditions will require special action. Some builders or homeowners will wish to do more than the important but basic retrofit strategies outlinedmore » by this guide. The following are best practice and product recommendations from the interviewed contractors and homebuilders who collectively have a vast amount of experience. Three significant items were discussed with the group which are required to make taped insulating sheathing a simple, long term, and durable drainage plane: 1. Horizontal joints should be limited or eliminated wherever possible; 2. Where a horizontal joint exists use superior materials; 3. Frequent installation inspection and regular trade training are required to maintain proper installation. Section 5 of this measure guideline contains the detailed construction procedure for the three recommended methods to effectively seal the joints in exterior insulating sheathing to create a simple, long term, and durable drainage plane.« less

Endoscope-Assisted Keyhole Technique for Hypertensive Cerebral Hemorrhage in Elderly Patients: A Randomized Controlled Study in 184 Patients.

PubMed

Feng, Yi; He, Jianqing; Liu, Bin; Yang, Likun; Wang, Yuhai

2016-01-01

Hypertensive cerebral hemorrhage (HCH) is a potentially life-threatening cerebrovascular disease with high mortality. In case of a massive hematoma, surgical drainage is a crucial treatment. The aim of the present study was to assess the efficacy of the endoscope-assisted keyhole technique in elderly patients with intracerebral hematoma who needed a flap craniotomy as traditional treatment. One hundred-eighty-four elderly patients with HCH, who had craniotomy indications after conservative treatment for 6-24 hours after onset, were randomly divided into two groups. In the craniotomy group, traditional hematoma drainage was performed. In the keyhole group, an endoscope-assisted keyhole technique was used. Anesthesia time, blood loss, hematoma drainage rate, and complications were compared. The clinical primary outcome was the six-month efficacy rate (defined by the activities of daily living (ADL) score). Anesthesia time was longer in the craniotomy group (3.43 ± 0.65 vs. 1.53 ± 0.52 h, P < 0.01), and blood losses were more important (256 ± 129 vs. 96 ± 39 ml P < 0.01). There was no difference in hematoma drainage rate between the two groups (77.25 ± 13.44 vs. 83.52 ± 27.51% P > 0.05). Complications, including tracheotomy (P < 0.01), pulmonary infection (P < 0.01) and hypoproteinemia (P < 0.05) were more frequent in the craniotomy group. There was no difference in the occurrence of other complications, including revision surgery digestive tract ulcer and epilepsy. Proportion of patients with good prognosis (ADL I-III) was larger in the keyhole group (P < 0.05). In elderly HCH patients with an indication for hematoma drainage, better outcomes were achieved using an endoscope-assisted keyhole technique.

MDCT Venography Evaluation of a Rare Collateral Vein Draining from the Left Subclavian Vein to the Great Cardiac Vein

PubMed Central

Abchee, Antoine; Saade, Charbel; Al-Mohiy, Hussain; El-Merhi, Fadi

2014-01-01

Congenital vascular anomalies of the venous drainage in the chest affect both cardiac and non-cardiac structures. Collateral venous drainage from the left subclavian vein to the great cardiac vein is a rare venous drainage pattern. These anomalies present a diagnostic challenge. Multi-detector computed tomography (MDCT) is useful in the diagnosis and treatment planning of these clinically complex disorders. We present a case report of an 18-year-old Caucasian male who came to our institute for evaluation of venous drainage patterns to the heart. We describe the contrast technique of bilateral dual injection MDCT venography and the imaging features of the venous drainage patterns to the heart. PMID:25379351

MDCT Venography Evaluation of a Rare Collateral Vein Draining from the Left Subclavian Vein to the Great Cardiac Vein.

PubMed

Abchee, Antoine; Saade, Charbel; Al-Mohiy, Hussain; El-Merhi, Fadi

2014-01-01

Congenital vascular anomalies of the venous drainage in the chest affect both cardiac and non-cardiac structures. Collateral venous drainage from the left subclavian vein to the great cardiac vein is a rare venous drainage pattern. These anomalies present a diagnostic challenge. Multi-detector computed tomography (MDCT) is useful in the diagnosis and treatment planning of these clinically complex disorders. We present a case report of an 18-year-old Caucasian male who came to our institute for evaluation of venous drainage patterns to the heart. We describe the contrast technique of bilateral dual injection MDCT venography and the imaging features of the venous drainage patterns to the heart.

Diagnostic imaging in ophthalmology

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gonzalez, C.F.; Becker, M.H.; Flanagan, J.C.

There are three sections in the book. The first section is a discussion of imaging techniques, which includes plain film radiography and multidirectional tomography of the orbit, computed tomography (CT) of the orbit and its use in the evaluation of ocular motility disorders, ultrasonography of the eye and orbit, investigation of the orbit by contrast techniques (which includes a brief review of angiography), the lachrimal drainage system, foreign body localization, and magnetic resonance imaging of the eye and orbit. There is extensive discussion of CT throughout the book. The second section is devoted to the role of these imaging methodsmore » in the evaluation of ophthalmic disorders. A discussion of congenital anomalies is useful for those centers that are exposed to unusual congenital anomalies and syndromes. Also included is evaluation of exophthalmous and thyroid ophthamalopathy, orbital tumors, lesions involving the visual pathways, CT assessment of paraorbital pathology (including basal and squamous cell tumors of the face), infection of the orbit, and orbital trauma. The third section is an overview of radiation therapy and malignant intraoccular tumors.« less

Best option for preoperative biliary drainage in Klatskin tumor

PubMed Central

Tang, Zengwei; Yang, Yuan; Meng, Wenbo; Li, Xun

2017-01-01

Abstract The operative treatment combined with preoperative biliary drainage (PBD) has been established as a safe Klatskin tumor (KT) treatment strategy. However, there has always been a dispute for the preferred technique for PBD technique. This meta-analysis was conducted to compare the biliary drainage-related cholangitis, pancreatitis, hemorrhage, and the success rates of palliative relief of cholestasis between percutaneous transhepatic biliary drainage (PTBD) and endoscopic biliary drainage (EBD), to identify the best technique in the management of KT. PubMed, EMBASE, and Web of Science were searched systematically for prospective or retrospective studies reporting the biliary drainage-related cholangitis, pancreatitis, hemorrhage, and the success rates of palliative relief of cholestasis in patients with KT. A meta-analysis was performed, using the fixed or random-effect model, with Review Manager 5.3. PTBD was associated with lower risk of cholangitis (risk ratio [RR] = 0.49, 95% confidence interval [CI]: 0.36–0.67; P < .00001), particularly in patients with Bismuth-Corlette type II, III, IV KT (RR = 0.50, 95% CI: 0.33–0.77; P = .05). Compared with EBD, PTBD was also associated with a lower risk of pancreatitis (RR = 0.35, 95% CI: 0.17–0.69; P = 0.003) and with higher successful rates of palliative relief of cholestasis (RR = 1.20, 95% CI: 1.10–1.31; P < .0001). The incidence of hemorrhage was similar in these 2 groups (RR 1.29, 95% CI: 0.51–3.27; P = .59). The risk of biliary drainage-related cholangitis (RR = 1.96, 95% CI: 0.96–4.01; P = .06) and pancreatitis (RR = 1.62, 95% CI: 0.76–3.47; P = .21) was similar between endoscopic nasobiliary drainage groups and biliary stenting. In patients with type II or type III or IV KT who need to have PBD, PTBD should be performed as an initial method of biliary drainage in terms of reducing the incidence of procedure related cholangitis, pancreatitis, and improving the rates of palliative relief of cholestasis. Well-conducted randomized controlled trials with a universial criterion for PBD are required to confirm these findings. PMID:29069029

[Lung abscess and necrotizing pneumonia: chest tube insertion or surgery?].

PubMed

Pagès, P-B; Bernard, A

2012-04-01

Lung abscesses and necrotizing pneumonia are rare complications of community-acquired pneumonia since the advent of antibiotics. Their management leans first of all on the antibiotic treatment adapted on the informed germs. However, in 11 to 20% of the cases of lung abscesses, this treatment is insufficient, and drainage, either endoscopic or percutaneous, must be envisaged. In first intention, we shall go to less invasive techniques: endoscopic or percutaneous radio-controlled. In case of failure of these techniques, a percutaneous surgical drainage by minithoracotomy will be performed. In the necrotizing pneumonia, because of the joint obstruction of the bronchus and blood vessels corresponding to a lung segment, the systemic antibiotic treatment will be poor effective. In case of failure of this one we shall propose, a percutaneous surgical drainage, especially if the necrosis limits itself to a single lobe. The surgical treatment will be reserved: in the failures of the strategy of surgical drainage, in the necroses extending in several lobes. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

Ultrasound-Guided Percutaneous Catheter Drainage of Large Breast Abscesses in Lactating Women: How to Preserve Breastfeeding Safely.

PubMed

Falco, Giuseppe; Foroni, Monica; Castagnetti, Fabio; Marano, Luigi; Bordoni, Daniele; Rocco, Nicola; Marchesi, Vanessa; Iotti, Valentina; Vacondio, Rita; Ferrari, Guglielmo

2016-12-01

Management of breast abscess in lactating women remains controversial. During pregnancy, women may develop different kinds of benign breast lesions that could require a surgical incision performed under general anesthesia with consequent breastfeeding interruption. The purpose of this study was to prospectively evaluate the management of large breast abscesses with ultrasound-assisted drainage aiming at breastfeeding preservation. 34 lactating women with a diagnosis of unilateral breast abscess have been treated with an ultrasound (US)-assisted drainage of the abscess. A pigtail catheter was inserted into the fluid collection using the Seldinger technique under US guide and connected to a three stop way to allow drainage and irrigation of the cavity until its resolution. All procedures have been found safe and well tolerated. No recurrence was observed and breastfeeding was never interrupted. The described technique allows to avoid surgery and to preserve breastfeeding in well-selected patients with a safe, well-tolerated and cost-effective procedure.

Robotic pancreas drainage procedure for chronic pancreatitis: robotic lateral pancreaticojejunostomy (Puestow procedure).

PubMed

Khan, Adeel S; Siddiqui, Imran; Vrochides, Dionisios; Martinie, John B

2018-01-01

Lateral pancreaticojejunostomy (LPJ), also known as the Puestow procedure, is a complex surgical procedure reserved for patients with refractory chronic pancreatitis (CP) and a dilated pancreatic duct. Traditionally, this operation is performed through an open incision, however, recent advancements in minimally invasive techniques have made it possible to perform the surgery using laparoscopic and robotic techniques with comparable safety. Though we do not have enough data yet to prove superiority of one over the other, the robotic approach appears to have an advantage over the laparoscopic technique in better visualization through 3-dimensional (3D) imaging and availability of wristed instruments for more precise actions, which may translate into superior outcomes. This paper is a description of our technique for robotic LPJ in patients with refractory CP. Important principles of patient selection, preoperative workup, surgical technique and post-operative management are discussed. A short video with a case presentation and highlights of the important steps of the surgery is included.

Robotic pancreas drainage procedure for chronic pancreatitis: robotic lateral pancreaticojejunostomy (Puestow procedure)

PubMed Central

Khan, Adeel S.; Siddiqui, Imran; Vrochides, Dionisios

2018-01-01

Lateral pancreaticojejunostomy (LPJ), also known as the Puestow procedure, is a complex surgical procedure reserved for patients with refractory chronic pancreatitis (CP) and a dilated pancreatic duct. Traditionally, this operation is performed through an open incision, however, recent advancements in minimally invasive techniques have made it possible to perform the surgery using laparoscopic and robotic techniques with comparable safety. Though we do not have enough data yet to prove superiority of one over the other, the robotic approach appears to have an advantage over the laparoscopic technique in better visualization through 3-dimensional (3D) imaging and availability of wristed instruments for more precise actions, which may translate into superior outcomes. This paper is a description of our technique for robotic LPJ in patients with refractory CP. Important principles of patient selection, preoperative workup, surgical technique and post-operative management are discussed. A short video with a case presentation and highlights of the important steps of the surgery is included. PMID:29780718

The Short-Term Effect of Breathing Tasks Via an Incentive Spirometer on Lung Function Compared With Autogenic Drainage in Subjects With Cystic Fibrosis.

PubMed

Sokol, Gil; Vilozni, Daphna; Hakimi, Ran; Lavie, Moran; Sarouk, Ifat; Bat-El Bar; Dagan, Adi; Ofek, Miryam; Efrati, Ori

2015-12-01

Forced expiration may assist secretion movement by manipulating airway dynamics in patients with cystic fibrosis (CF). Expiratory resistive breathing via a handheld incentive spirometer has the potential to control the expiratory flow via chosen resistances (1-8 mm) and thereby mobilize secretions and improve lung function. Our objective was to explore the short-term effect of using a resistive-breathing incentive spirometer on lung function in subjects with CF compared with the autogenic drainage technique. This was a retrospective study. Subjects with CF performed 30-45 min of either the resistive-breathing incentive spirometer (n = 40) or autogenic drainage (n = 32) technique on separate days. The spirometer encourages the patient to exhale as long as possible while maintaining a low lung volume. The autogenic drainage technique includes repetitive inspiratory and expiratory maneuvers at various tidal breathing magnitudes while exhalation is performed in a sighing manner. Spirometry was performed before and 20-30 min after the therapy. Use of a resistive-breathing incentive spirometer improved FVC and FEV1 by 5-42% in 26 subjects. The forced expiratory flow during the middle half of the FVC maneuver (FEF25-75%) improved by >20% in 9 (22%) subjects. FVC improved the most in subjects with an FEV1 of 40-60% of predicted. Improvements negatively correlated with baseline percent-of-predicted FVC values provided improvements were above 10% (r(2) = 0.28). Values improved in a single subjects using the autogenic drainage technique. These 2 techniques may allow lower thoracic pressures and assist in the prevention of central airway collapse. The resistive-breathing incentive spirometer is a self-administered simple method that may aid airway clearance and has the potential to improve lung function as measured by FVC, FEV1, and FEF25-75% in patients with CF. Copyright © 2015 by Daedalus Enterprises.

The Seepage Simulation of Single Hole and Composite Gas Drainage Based on LB Method

NASA Astrophysics Data System (ADS)

Chen, Yanhao; Zhong, Qiu; Gong, Zhenzhao

2018-01-01

Gas drainage is the most effective method to prevent and solve coal mine gas power disasters. It is very important to study the seepage flow law of gas in fissure coal gas. The LB method is a simplified computational model based on micro-scale, especially for the study of seepage problem. Based on fracture seepage mathematical model on the basis of single coal gas drainage, using the LB method during coal gas drainage of gas flow numerical simulation, this paper maps the single-hole drainage gas, symmetric slot and asymmetric slot, the different width of the slot combined drainage area gas flow under working condition of gas cloud of gas pressure, flow path diagram and flow velocity vector diagram, and analyses the influence on gas seepage field under various working conditions, and also discusses effective drainage method of the center hole slot on both sides, and preliminary exploration that is related to the combination of gas drainage has been carried on as well.

New technique for treating pseudocyst of the auricle.

PubMed

Zhu, L X; Wang, X Y

1990-01-01

Although pseudocyst of the auricle is a common disease in China, its cause and mechanism are still not clear. Several methods of treatment have been advocated: repeated aspirations combined with physiotherapy, and incision and drainage with contour pressure dressing, magnetotherapy etc. In recent years, a new technique with a drainage tube inserted into the pseudocyst using a guide needle has been used in our hospital in the treatment of this condition. We report 45 cases treated by this method, none of whom had the condition previously.

Comparison of two stochastic techniques for reliable urban runoff prediction by modeling systematic errors

NASA Astrophysics Data System (ADS)

Del Giudice, Dario; Löwe, Roland; Madsen, Henrik; Mikkelsen, Peter Steen; Rieckermann, Jörg

2015-07-01

In urban rainfall-runoff, commonly applied statistical techniques for uncertainty quantification mostly ignore systematic output errors originating from simplified models and erroneous inputs. Consequently, the resulting predictive uncertainty is often unreliable. Our objective is to present two approaches which use stochastic processes to describe systematic deviations and to discuss their advantages and drawbacks for urban drainage modeling. The two methodologies are an external bias description (EBD) and an internal noise description (IND, also known as stochastic gray-box modeling). They emerge from different fields and have not yet been compared in environmental modeling. To compare the two approaches, we develop a unifying terminology, evaluate them theoretically, and apply them to conceptual rainfall-runoff modeling in the same drainage system. Our results show that both approaches can provide probabilistic predictions of wastewater discharge in a similarly reliable way, both for periods ranging from a few hours up to more than 1 week ahead of time. The EBD produces more accurate predictions on long horizons but relies on computationally heavy MCMC routines for parameter inferences. These properties make it more suitable for off-line applications. The IND can help in diagnosing the causes of output errors and is computationally inexpensive. It produces best results on short forecast horizons that are typical for online applications.

AGRICULTURAL DRAINAGE WELLS: IMPACT ON GROUND WATER

EPA Science Inventory

This document discusses agricultural drainage well practices, potential contamination problems that may occur, and possible management practices or regulatory solutions that could be used to alleviate those problems. The document has been written for use by state and Agency deci...

Red rubber bulb, cheap and effective vacuum drainage.

PubMed

Vatanasapt, V; Areemit, S; Jeeravipoolvarn, P; Kuyyakanond, T; Kuptarnond, C

1989-04-01

Red rubber bulbs have been used for vacuum drainage in head, neck, breast and several other operations by the authors since 1975 quite effectively without any major problems. The vacuum pressure of the red rubber bulbs was found to be higher than the expensive commercially available vacuum wound drainage device. The question of remaining old blood and infective microorganisms inside the reservoir for the reused ones were tested by the manual cleaning process and the standard sterile technique using steam under increased pressure (autoclave). The result is quite satisfactory. We encourage the use of this cheap and effective (made in Thailand) vacuum wound drainage in Thai hospitals and Thai medical schools.

Physical aquatic habitat assessment data, Ozark plateaus, Missouri and Arkansas

USGS Publications Warehouse

Jacobson, Robert B.; Johnson, Harold E.; Reuter, Joanna M.; Wright, Maria Panfil

2004-01-01

This report presents data from two related studies on physical habitat in small streams in the Ozark Plateaus Physiographic Province of Missouri and Arkansas. Seventy stream reaches and their contributing drainage basins were assessed using a physical habitat protocol designed to optimize understanding of how stream reach characteristics relate to drainage-basin characteristics. Drainage-basin characteristics were evaluated using geographic information system (GIS) techniques and datasets designed to evaluate the geologic, physiographic, and land-use characteristics of encompassing drainage basins. Reach characteristics were evaluated using a field-based geomorphology and habitat protocol. The data are intended to complement ecological studies on Ozark Plateaus streams.

Endoscopic ultrasound-guided biliary drainage

PubMed Central

Chavalitdhamrong, Disaya; Draganov, Peter V

2012-01-01

Endoscopic ultrasound (EUS)-guided biliary drainage has emerged as a minimally invasive alternative to percutaneous and surgical interventions for patients with biliary obstruction who had failed endoscopic retrograde cholangiopancreatography (ERCP). EUS-guided biliary drainage has become feasible due to the development of large channel curvilinear therapeutic echo-endoscopes and the use of real-time ultrasound and fluoroscopy imaging in addition to standard ERCP devices and techniques. EUS-guided biliary drainage is an attractive option because of its minimally invasive, single step procedure which provides internal biliary decompression. Multiple investigators have reported high success and low complication rates. Unfortunately, high quality prospective data are still lacking. We provide detailed review of the use of EUS for biliary drainage from the perspective of practicing endoscopists with specific focus on the technical aspects of the procedure. PMID:22363114

The effectiveness of simple drainage technique in improvement of cerebral blood flow in patients with chronic subdural hemorrhage.

PubMed

Kaplan, Metin; Erol, Fatih Serhat; Bozgeyik, Zülküf; Koparan, Mehmet

2007-07-01

In the present study, the clinical effectiveness of a surgical procedure in which no draining tubes are installed following simple burr hole drainage and saline irrigation is investigated. 10 patients, having undergone operative intervention for unilateral chronic subdural hemorrhage, having a clinical grade of 2 and a hemorrhage thickness of 2 cm, were included in the study. The cerebral blood flow rates of middle cerebral artery were evaluated bilaterally with Doppler before and after the surgery. All the cases underwent the operation using the simple burr hole drainage technique without the drain and consequent saline irrigation. Statistical analysis was performed by Wilcoxon signed rank test (p<0.05). There was a pronounced decrease in the preoperative MCA blood flow in the hemisphere the hemorrhage had occurred (p=0.008). An increased PI value on the side of the hemorrhage drew our attention (p=0.005). Postoperative MCA blood flow measurements showed a statistically significant improvement (p=0.005). Furthermore, the PI value showed normalization (p<0.05). The paresis and the level of consciousness improved in all cases. Simple burr hole drainage technique is sufficient for the improvement of cerebral blood flow and clinical recovery in patients with chronic subdural hemorrhage.

Endoscopic Ultrasound-guided Bilio-pancreatic Drainage

PubMed Central

Giovannini, Marc; Bories, Erwan; Téllez-Ávila, Félix I.

2012-01-01

The echoendoscopic biliary drainage is an option to treat obstructive jaundices when endoscopic retrograde cholangiopancreatography (ERCP) drainage fails. These procedures compose alternative methods to the side of surgery and percutaneous transhepatic biliary drainage, and it was only possible by the continuous development and improvement of echoendoscopes and accessories. The development of linear sectorial array echoendoscopes in early 1990 brought a new approach to diagnostic and therapeutic dimension on echoendoscopy capabilities, opening the possibility to perform punction over direct ultrasonografic view. Despite of the high success rate and low morbidity of biliary drainage obtained by ERCP, difficulty could be found at the presence of stent tumor ingrown, tumor gut compression, periampullary diverticula and anatomic variation. The echoendoscopic technique starts performing punction and contrast of the left biliary tree. When performed from gastric wall, the access is made through hepatic segment III. From duodenum, direct common bile duct punction. Diathermic dilatation of the puncturing tract is required using a 6-Fr cystostome and a plastic or metal stent is introducted. The techincal success of hepaticogastrostomy is near 98%, and complications are present in 20%: pneumoperitoneum, choleperitoneum, infection and stent disfunction. To prevent bile leakage, we have used the 2-stent techniques. The first stent introduced was a long uncovered metal stent (8 or 10 cm) and inside this first stent a second fully covered stent of 6 cm was delivered to bridge the bile duct and the stomach. Choledochoduodenostomy overall success rate is 92%, and described complications include, in frequency order, pneumoperitoneum and focal bile peritonitis, present in 14%. By the last 10 years, the technique was especially performed in reference centers, by ERCP experienced groups, and this seems to be a general guideline to safer procedure execution. The ideal approach for pancreatic pseudocyst (PPC) puncture combines endos-copy with real time endosonography using an interventional echoendoscope. Several authors have described the use of endoscopic ultrasound (EUS) longitudinal scanners for guidance of transmural puncture and drainage procedures. The same technique could be used to access a dilated pancreatic duct in cases in which the duct cannot be drained by conventional ERCP because of complete obstruction. PMID:24949349

HANDBOOK: RETROFITTING POTWS FOR PHOSPHORUS REMOVAL IN THE CHESAPEAKE BAY DRAINAGE BASIN

EPA Science Inventory

This document assesses the technology, economics, and efficiency of phosphorus removal processes for use in the Chesapeake Bay Drainage basin (CBDB). ince phosphorus removal requirements in the CBDB vary widely with geographic location, this document discusses the feasibility of ...

Reality named endoscopic ultrasound biliary drainage

PubMed Central

Guedes, Hugo Gonçalo; Lopes, Roberto Iglesias; de Oliveira, Joel Fernandez; Artifon, Everson Luiz de Almeida

2015-01-01

Endoscopic ultrasound (EUS) is used for diagnosis and evaluation of many diseases of the gastrointestinal (GI) tract. In the past, it was used to guide a cholangiography, but nowadays it emerges as a powerful therapeutic tool in biliary drainage. The aims of this review are: outline the rationale for endoscopic ultrasound-guided biliary drainage (EGBD); detail the procedural technique; evaluate the clinical outcomes and limitations of the method; and provide recommendations for the practicing clinician. In cases of failed endoscopic retrograde cholangiopancreatography (ERCP), patients are usually referred for either percutaneous transhepatic biliary drainage (PTBD) or surgical bypass. Both these procedures have high rates of undesirable complications. EGBD is an attractive alternative to PTBD or surgery when ERCP fails. EGBD can be performed at two locations: transhepatic or extrahepatic, and the stent can be inserted in an antegrade or retrograde fashion. The drainage route can be transluminal, duodenal or transpapillary, which, again, can be antegrade or retrograde [rendezvous (EUS-RV)]. Complications of all techniques combined include pneumoperitoneum, bleeding, bile leak/peritonitis and cholangitis. We recommend EGBD when bile duct access is not possible because of failed cannulation, altered upper GI tract anatomy, gastric outlet obstruction, a distorted ampulla or a periampullary diverticulum, as a minimally invasive alternative to surgery or radiology. PMID:26504507

Endoscopic Gallbladder Drainage for Acute Cholecystitis

PubMed Central

Widmer, Jessica; Alvarez, Paloma; Sharaiha, Reem Z.; Gossain, Sonia; Kedia, Prashant; Sarkaria, Savreet; Sethi, Amrita; Turner, Brian G.; Millman, Jennifer; Lieberman, Michael; Nandakumar, Govind; Umrania, Hiren; Gaidhane, Monica

2015-01-01

Background/Aims Surgery is the mainstay of treatment for cholecystitis. However, gallbladder stenting (GBS) has shown promise in debilitated or high-risk patients. Endoscopic transpapillary GBS and endoscopic ultrasound-guided GBS (EUS-GBS) have been proposed as safe and effective modalities for gallbladder drainage. Methods Data from patients with cholecystitis were prospectively collected from August 2004 to May 2013 from two United States academic university hospitals and analyzed retrospectively. The following treatment algorithm was adopted. Endoscopic retrograde cholangiopancreatography (ERCP) with sphincterotomy and cystic duct stenting was initially attempted. If deemed feasible by the endoscopist, EUS-GBS was then pursued. Results During the study period, 139 patients underwent endoscopic gallbladder drainage. Among these, drainage was performed in 94 and 45 cases for benign and malignant indications, respectively. Successful endoscopic gallbladder drainage was defined as decompression of the gallbladder without incidence of cholecystitis, and was achieved with ERCP and cystic duct stenting in 117 of 128 cases (91%). Successful endoscopic gallbladder drainage was also achieved with EUS-guided gallbladder drainage using transmural stent placement in 11 of 11 cases (100%). Complications occurred in 11 cases (8%). Conclusions Endoscopic gallbladder drainage techniques are safe and efficacious methods for gallbladder decompression in non-surgical patients with comorbidities. PMID:26473125

Transurethral Drainage of Prostatic Abscess: Points of Technique

PubMed Central

El-Shazly, Mohamed; El- Enzy, Nawaf; El-Enzy, Khaled; Yordanov, Encho; Hathout, Badawy; Allam, Adel

2012-01-01

Background The incidence of prostatic abscess (PA) has markedly declined with the widespread use of antibiotics and the decreasing incidence of urethral gonococcal infections. Objectives To evaluate different treatment methods for prostatic abscess and to describe technical points that will improve the outcome of transurethral (TUR) drainage of prostatic abscess. Patients and Methods We performed a retrospective study of a series of 11 patients diagnosed with prostatic abscess, who were admitted and treated in Farwaniya Hospital, Kuwait, between February 2008 and November 2010. Drainage was indicated when antibiotic therapy did not cause clinical improvement and after prostatic abscess was confirmed by TRUS (Transrectal ultrasonography) and/or CT computed Tomographyscan. TUR drainage was indicated in 7 cases, ultrasound-guided transrectal drainage was performed in 2 cases, and ultrasound-guided perineal drainage was performed in 2 cases. Results All patients that underwent TUR-drainage had successful outcomes, without the need of secondary treatment or further surgery. Conclusions TUR drainage of a prostatic abscess increases the likelihood of a successful outcome and lowers the incidence of treatment failure or repeated surgery. Less invasive treatment, with perineal or transrectal aspiration, may be preferred as a primary treatment in relatively young patients with localized abscess cavities. PMID:23573466

Evaluation of drainage-area ratio method used to estimate streamflow for the Red River of the North Basin, North Dakota and Minnesota

USGS Publications Warehouse

Emerson, Douglas G.; Vecchia, Aldo V.; Dahl, Ann L.

2005-01-01

The drainage-area ratio method commonly is used to estimate streamflow for sites where no streamflow data were collected. To evaluate the validity of the drainage-area ratio method and to determine if an improved method could be developed to estimate streamflow, a multiple-regression technique was used to determine if drainage area, main channel slope, and precipitation were significant variables for estimating streamflow in the Red River of the North Basin. A separate regression analysis was performed for streamflow for each of three seasons-- winter, spring, and summer. Drainage area and summer precipitation were the most significant variables. However, the regression equations generally overestimated streamflows for North Dakota stations and underestimated streamflows for Minnesota stations. To correct the bias in the residuals for the two groups of stations, indicator variables were included to allow both the intercept and the coefficient for the logarithm of drainage area to depend on the group. Drainage area was the only significant variable in the revised regression equations. The exponents for the drainage-area ratio were 0.85 for the winter season, 0.91 for the spring season, and 1.02 for the summer season.

Automatic Generalizability Method of Urban Drainage Pipe Network Considering Multi-Features

NASA Astrophysics Data System (ADS)

Zhu, S.; Yang, Q.; Shao, J.

2018-05-01

Urban drainage systems are indispensable dataset for storm-flooding simulation. Given data availability and current computing power, the structure and complexity of urban drainage systems require to be simplify. However, till data, the simplify procedure mainly depend on manual operation that always leads to mistakes and lower work efficiency. This work referenced the classification methodology of road system, and proposed a conception of pipeline stroke. Further, length of pipeline, angle between two pipelines, the pipeline belonged road level and diameter of pipeline were chosen as the similarity criterion to generate the pipeline stroke. Finally, designed the automatic method to generalize drainage systems with the concern of multi-features. This technique can improve the efficiency and accuracy of the generalization of drainage systems. In addition, it is beneficial to the study of urban storm-floods.

Use of a flux-based field capacity criterion to identify effective hydraulic parameters of layered soil profiles subjected to synthetic drainage experiments

NASA Astrophysics Data System (ADS)

Nasta, Paolo; Romano, Nunzio

2016-01-01

This study explores the feasibility of identifying the effective soil hydraulic parameterization of a layered soil profile by using a conventional unsteady drainage experiment leading to field capacity. The flux-based field capacity criterion is attained by subjecting the soil profile to a synthetic drainage process implemented numerically in the Soil-Water-Atmosphere-Plant (SWAP) model. The effective hydraulic parameterization is associated to either aggregated or equivalent parameters, the former being determined by the geometrical scaling theory while the latter is obtained through the inverse modeling approach. Outcomes from both these methods depend on information that is sometimes difficult to retrieve at local scale and rather challenging or virtually impossible at larger scales. The only knowledge of topsoil hydraulic properties, for example, as retrieved by a near-surface field campaign or a data assimilation technique, is often exploited as a proxy to determine effective soil hydraulic parameterization at the largest spatial scales. Comparisons of the effective soil hydraulic characterization provided by these three methods are conducted by discussing the implications for their use and accounting for the trade-offs between required input information and model output reliability. To better highlight the epistemic errors associated to the different effective soil hydraulic properties and to provide some more practical guidance, the layered soil profiles are then grouped by using the FAO textural classes. For the moderately heterogeneous soil profiles available, all three approaches guarantee a general good predictability of the actual field capacity values and provide adequate identification of the effective hydraulic parameters. Conversely, worse performances are encountered for the highly variable vertical heterogeneity, especially when resorting to the "topsoil-only" information. In general, the best performances are guaranteed by the equivalent parameters, which might be considered a reference for comparisons with other techniques. As might be expected, the information content of the soil hydraulic properties pertaining only to the uppermost soil horizon is rather inefficient and also not capable to map out the hydrologic behavior of the real vertical soil heterogeneity since the drainage process is significantly affected by profile layering in almost all cases.

Experience with 100 consecutive simultaneous kidney-pancreas transplants with bladder drainage.

PubMed Central

Sollinger, H W; Knechtle, S J; Reed, A; D'Alessandro, A M; Kalayoglu, M; Belzer, F O; Pirsch, J

1991-01-01

From December 1985 to December 1989, 100 consecutive simultaneous pancreas-kidney (SPK) transplants were performed at the University of Wisconsin Hospital and Clinics. Bladder drainage technique was used for all grafts. One- and three-year patient survival was 93% and 90%; kidney survival, 90% and 85%; and pancreas survival, 86% and 84%. Quadruple immunosuppressive therapy was used in all patients and consisted of either MALG or OKT3 induction, and cyclosporine, prednisone, and azathioprine maintenance therapy. OKT3 induction therapy was used in 42 patients and Minnesota antilymphocyte globule in 58 patients, with equivalent results except for more opportunistic infection with OKT3. The duodenal button technique was used in the first 17 patients with systemic anticoagulation and was associated with significantly more postoperative bleeding and infection compared with the duodenal segment technique. The most common surgical complication of the duodenal segment technique was urine leak (13%), which usually occurred from the distal duodenal segment. The most common urologic complication of bladder drainage was hematuria (13%), which was usually self-limited. Within 6 months of transplantation, 84% of patients developed urinary tract infections, and 25% of patients had opportunistic infections. The surgical techniques and immunosuppressive methods used in this series are reviewed, and strategies for preventing medical and surgical complications are outlined. PMID:1741650

Prevention of intraoperative cerebrospinal fluid leaks by lumbar cerebrospinal fluid drainage during surgery for pituitary macroadenomas.

PubMed

Mehta, Gautam U; Oldfield, Edward H

2012-06-01

Cerebrospinal fluid leakage is a major complication of transsphenoidal surgery. An intraoperative CSF leak, which occurs in up to 50% of pituitary tumor cases, is the only modifiable risk factor for postoperative leaks. Although several techniques have been described for surgical repair when an intraoperative leak is noted, none has been proposed to prevent an intraoperative CSF leak. The authors postulated that intraoperative CSF drainage would diminish tension on the arachnoid, decrease the rate of intraoperative CSF leakage during surgery for larger tumors, and reduce the need for surgical repair of CSF leaks. The results of 114 transsphenoidal operations for pituitary macroadenoma performed without intraoperative CSF drainage were compared with the findings from 44 cases in which a lumbar subarachnoid catheter was placed before surgery to drain CSF at the time of dural exposure and tumor removal. Cerebrospinal fluid drainage reduced the rate of intraoperative CSF leakage from 41% to 5% (p < 0.001). This reduction occurred in macroadenomas with (from 57% to 5%, p < 0.001) and those without suprasellar extension (from 29% to 0%, p = 0.31). The rate of postoperative CSF leakage was similar (5% vs 5%), despite the fact that intraoperative CSF drainage reduced the need for operative repair (from 32% to 5%, p < 0.001). There were no significant catheter-related complications. Cerebrospinal fluid drainage during transsphenoidal surgery for macroadenomas reduces the rate of intraoperative CSF leaks. This preventative measure obviated the need for surgical repair of intraoperative CSF leaks using autologous fat graft placement, other operative techniques, postoperative lumbar drainage, and/or reoperation in most patients and is associated with minimal risks.

Innovative Technique for the Placement of the Drainage Tube for Microendoscopic Spinal Decompression.

PubMed

Mizuno, Kentaro; Mikami, Yasuo; Hase, Hitoshi; Ikeda, Takumi; Nagae, Masateru; Tonomura, Hitoshi; Shirai, Toshiharu; Fujiwara, Hiroyoshi; Kubo, Toshikazu

2017-02-01

A technical note and retrospective study. The objectives were to describe a new method of drainage tube placement during microendoscopic spinal decompression, and compare the positioning and fluid discharge obtained with this method and the conventional method. To prevent postoperative epidural hematoma after microendoscopic decompression, a drainage tube must be placed in a suitable location. However, the narrow operative field makes precise control of the position of the tube technically difficult. We developed a method to reliably place the tube in the desired location. We use a Deschamps aneurysm needle with a slightly curved tip, which we call a drain passer. With the microendoscope in position, the drain passer, with a silk thread passed through the eye at the needle tip, is inserted percutaneously into the endoscopic field of view. The drainage tube is passed through the loop of silk thread protruding from the inside of the tubular retractor, and the thread is pulled to the outside, guiding the end of the drainage tube into the wound. This method was used in 23 cases at 44 intervertebral levels (drain passer group), and the conventional method in 20 cases at 32 intervertebral levels (conventional group). Postoperative plain radiographs were taken, and the amount of fluid discharge at postoperative hour 24 was measured. Drainage tube positioning was favorable at 43 intervertebral levels (97.7%) in the drain passer group and 26 intervertebral levels (81.3%) in the conventional group. Mean fluid discharge was 58.4±32.2 g in the drain passer group and 38.4±23.0 g in the conventional group. Positioning was significantly better and fluid discharge was significantly greater in the drain passer group. The results indicate that this method is a useful drainage tube placement technique for preventing postoperative epidural hematoma.

Management of traumatic hemothorax by closed thoracic drainage using a central venous catheter

PubMed Central

Yi, Jian-hua; Liu, Hua-bo; Zhang, Mao; Wu, Jun-song; Yang, Jian-xin; Chen, Jin-ming; Xu, Shan-xiang; Wang, Jian-an

2012-01-01

Objective: To evaluate the efficacy and safety of the treatment of traumatic hemothorax by closed pleural drainage using a central venous catheter (CVC), compared with using a conventional chest tube. Methods: A prospective controlled study with the Ethics Committee approval was undertaken. A total of 407 patients with traumatic hemothorax were involved and they were randomly assigned to undergo closed pleural drainage with CVCs (n=214) or conventional chest tubes (n=193). The Seldinger technique was used for drainage by CVC, and the conventional technique for drainage by chest tube. If the residual volume of the hemothorax was less than 200 ml after the daily volume of drainage decreased to below 100 ml for two consecutive days, the treatment was considered successful. The correlative data of efficacy and safety between the two groups were analyzed using t or chi-squared tests with SPSS 13.0. A P value of less than 0.05 was taken as indicating statistical significance. Results: Compared with the chest tube group, the operation time, fraction of analgesic treatment, time of surgical wound healing, and infection rate of surgical wounds were significantly decreased (P<0.05) in the CVC group. There were no significant differences between the two groups in the success rate of treatment and the incidence of serious complications (P>0.05), or in the mean catheter/tube indwelling time and mean medical costs of patients treated successfully (P>0.05). Conclusions: Management of medium or large traumatic hemothoraxes by closed thoracic drainage using CVC is minimally invasive and as effective as using a conventional large-bore chest tube. Its complications can be prevented and it has the potential to replace the large-bore chest tube. PMID:22205619

Building America Case Study: Measure Guideline: Guidance on Taped Insulating Sheathing Drainage Planes (Fact Sheet)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

This guide provides information and recommendations to the following groups: Insulation contractors, General contractors, Builders, Home remodelers, Mechanical contractors, and Homeowners as a guide to the work that needs to be done. The order of work completed during home construction and retrofit improvements is important. Health and safety issues must be addressed first and are more important than durability issues. And durability issues are more important than saving energy. Not all techniques can apply to all houses. Special conditions will require special action. Some builders or homeowners will wish to do more than the important but basic retrofit strategies outlinedmore » by this guide. The following are best practice and product recommendations from the interviewed contractors and home builders who collectively have a vast amount of experience. Three significant items were discussed with the group which are required to make taped insulating sheathing a simple, long term, and durable drainage plane: 4. Horizontal joints should be limited or eliminated wherever possible 5. Where a horizontal joint exists use superior materials 6. Frequent installation inspection and regular trade training are required to maintain proper installation Section 5 of this measure guideline contains the detailed construction procedure for the three recommended methods to effectively seal the joints in exterior insulating sheathing to create a simple, long term, and durable drainage plane.« less

Terrestrial and Aerial Ground-Penetrating Radar in Use for the Architectural Researches: Ancient 16TH Century Water Supply and Drainage at the Monastery of EL Escorial (madrid, Spain)

NASA Astrophysics Data System (ADS)

Chias, P.; Abad, T.; Echeverria, E.

2013-07-01

Remote sensing techniques in Archaeology are increasingly essential components of the methodologies used in archaeological and architectural researches. They allow uncovering unique forgotten data which are unobtainable using traditional excavation techniques, mainly because their precise location is lost. These data are still important since they can help to prevent flood effects inside the ancient building cellars and basements, as it happened periodically in El Escorial. Wide ancient drainage galleries run more than one hundred feet downhill outside the building, ensuring that rainwater and springs were adequately drained. Nowadays their plans are lost, and the lack of documents related both to the ancient water supply and drainage systems become an impediment to solve the stains of damp on the stone masonry walls and vaults, and even other occasional flooding effects. In this case, nondestructive techniques were needed to find the ancient underground passages in order to preserve the integrity of the building and its current activities. At a first stage oblique aerial infrared images taken from a helium barrage balloon helped to find easily, quickly and cheaply the buried masonry structures. Secondly, radar pulses were particularly interesting to image the subsurface as they were valuable means of assessing the presence and amount of both soil water and buried structures. The combination of both techniques proved to be an accurate and low-cost way to find the ancient drainage systems. Finally, results were produced by means of open source software.

A closed system irrigation & drainage technique for surgical evacuation of chronic subdural haematomas

PubMed Central

Kareem, Haider; Adams, Hadie

2018-01-01

Background: Chronic subdural haematoma (CSDH), is a common neurosurgical disorder that is associated with morbidity and mortality affecting the ageing population. The aim is to present the treatment experience of CSDH patients treated with a technique that combines the classical single burr-hole irrigation and the continuous closed system drainage: The closed system irrigation & drainage (CSID) technique. Methods: The cases undergoing CSDH evacuation with the CSID method were captured over a 4-year period at a tertiary neurosurgical centre. The authors describe the performance of this methods with respect to post-operative clinical and radiological features, including recurrence rates, complications, and length of stay. Results: A total of 36 cases undergoing 42 CSID procedures (30 unilateral and 6 bilateral CSDHs) were performed, in cases ranging between 55-95 years old (median age 79 years). The rate of recurrence or significant ruminant blood in the subdural space on post-operative imaging was 11% (n=4). No cases of pneumocephalus were observed in this series (n=0). The mean (SD) skin-to-skin time for this procedure was 13.4 (4.4) minutes, with a mean (SD) length of stay of 4 (1.9) days. Conclusion: We conclude that the one burr-hole closed system irrigation and drainage technique with a sub-periosteal drain seems to be a simple, effective and safe procedure for treatment of CSDH. It’s well tolerated under local anaesthesia for patients with high co-morbidities and these preliminary results indicated it may potentially be a better option for treatment of CSDH with a lower rate of post-operative complications. PMID:29904602

Combined ultrasonographically guided drainage and laparoscopic excision of a large ovarian cyst.

PubMed

Nagele, F; Magos, A L

1996-11-01

Large ovarian cysts are conventionally treated by laparotomy. We describe a technique of transabdominal drainage under ultrasonographic control followed by laparoscopic excision of an ovarian cyst that was 24 x 10 x 20 cm. This approach has the benefits of minimal-access surgery and is suitable for unilocular benign cysts of any size.

Endoscopic management of peripancreatic fluid collections.

PubMed

Goyal, Jatinder; Ramesh, Jayapal

2015-07-01

Peripancreatic fluid collections are a well-known complication of pancreatitis and can vary from fluid-filled collections to entirely necrotic collections. Although most of the fluid-filled pseudocysts tend to resolve spontaneously with conservative management, intervention is necessary in symptomatic patients. Open surgery has been the traditional treatment modality of choice though endoscopic, laparoscopic and transcutaneous techniques offer alternative drainage approaches. During the last decade, improvement in endoscopic ultrasound technology has enabled real-time access and drainage of fluid collections that were previously not amenable to blind transmural drainage. This has initiated a trend towards use of this modality for treatment of pseudocysts. In this review, we have summarised the existing evidence for endoscopic drainage of peripancreatic fluid collections from published studies.

CT-Guided Placement of a Drainage Catheter Within a Pelvic Abscess Using a Transsacral Approach

DOE Office of Scientific and Technical Information (OSTI.GOV)

Iguchi, Toshihiro; Asami, Shinya; Kubo, Shinichiro

2007-11-15

A 66-year-old man underwent CT-guided drainage catheter placement within a pelvic abscess with a diameter of 46 mm. We performed the drainage by a transsacral approach because it was considered the safest and most feasible approach. An 8G bone marrow biopsy needle was used to penetrate the sacrum to create a path for subsequent drainage catheter insertion. After withdrawal of the biopsy needle, a 6 Fr catheter was advanced into the abscess cavity through the path using the Seldinger technique. Except for bearable pain, no procedure-related complications occurred. Twenty-nine days after the placement, the catheter was withdrawn safely and themore » abscess cavity had shrunk remarkably.« less

New Technique of Exposed Glaucoma Drainage Tube Repair: Report of a Case.

PubMed

Berezina, Tamara L; Fechtner, Robert D; Cohen, Amir; Kim, Eliott E; Chu, David S

2015-01-01

We present the case of successful repair of an exposed glaucoma drainage tube by cornea graft fixation with tissue adhesive, and without subsequent coverage by adjacent conjunctiva or donor tissues. Patient with history of keratoglobus with thin cornea and sclera, and phthisical contralateral eye, underwent three unsuccessful corneal grafts followed by Boston type 1 keratoprosthesis in the right eye. Ahmed drainage device with sclera patch graft was implanted to control the intraocular pressure. Two years later the tube eroded through sclera graft and conjunctiva. Repair was performed by covering the tube with a corneal patch graft secured by tissue adhesive after the conjunctiva in this area was dissected away. The cornea graft was left uncovered due to fragility of adjacent conjunctiva. The healing of ocular and graft surfaces was complete prior to the 1 month follow-up. Conjunctival epithelium covered the corneal patch graft. At 12 months follow-up, the graft and the tube remained stable. Our report suggests that corneal patch graft fixation to the sclera by means of tissue adhesive, without closing the conjunctiva, can be considered as an effective alternative surgical approach for managing exposed glaucoma drainage tube, accompanied by adjacent conjunctiva tissue deficiency. How to cite this article: Berezina TL, Fechtner RD, Cohen A, Kim EE, Chu DS. New Technique of Exposed Glaucoma Drainage Tube Repair: Report of a Case. J Curr Glaucoma Pract 2015;9(2):62-64.

Lumen apposing metal stents for pancreatic fluid collections: Recognition and management of complications.

PubMed

DeSimone, Michael L; Asombang, Akwi W; Berzin, Tyler M

2017-09-16

For patients recovering from acute pancreatitis, the development of a pancreatic fluid collection (PFC) predicts a more complex course of recovery, and introduces difficult management decisions with regard to when, whether, and how the collection should be drained. Most PFCs resolve spontaneously and drainage is indicated only in pseudocysts and walled-off pancreatic necrosis when the collections are causing symptoms and/or local complications such as biliary obstruction. Historical approaches to PFC drainage have included surgical (open or laparoscopic cystgastrostomy or pancreatic debridement), and the placement of percutaneous drains. Endoscopic drainage techniques have emerged in the last several years as the preferred approach for most patients, when local expertise is available. Lumen-apposing metal stents (LAMS) have recently been developed as a tool to facilitate potentially safer and easier endoscopic drainage of pancreatic fluid collections, and less commonly, for other indications, such as gallbladder drainage. Physicians considering LAMS placement must be aware of the complications most commonly associated with LAMS including bleeding, migration, buried stent, stent occlusion, and perforation. Because of the patient complexity associated with severe pancreatitis, management of pancreatic fluid collections can be a complex and multidisciplinary endeavor. Successful and safe use of LAMS for patients with pancreatic fluid collections requires that the endoscopist have a full understanding of the potential complications of LAMS techniques, including how to recognize and manage expected complications.

Clinical outcomes of percutaneous drainage of breast fluid collections following mastectomy with expander-based breast reconstruction

PubMed Central

2015-01-01

PURPOSE To determine clinical outcomes of patients who underwent imaging-guided percutaneous drainage of breast fluid collections following mastectomy and breast reconstruction. MATERIAL AND METHODS Retrospective review included all consecutive patients who underwent percutaneous drainage of fluid collections following mastectomy with tissue expander-based reconstruction between January 2007 and September 2012. A total of 879 mastectomies (563 patients) with expander-based breast reconstruction were performed during this period. 28 patients (5%) developed fluid collections, which led to 30 imaging-guided percutaneous drainage procedures. The median follow up time was 533 days. Patient characteristics, surgical technique, microbiology analysis, and clinical outcomes were reviewed. RESULTS The mean age was 51.5 years (range 30.9 to 69.4 years) and the median time between breast reconstruction and drainage was 35 days (range 4 to 235 days). Erythema and swelling were the most common presenting symptoms. The median volume of fluid evacuated at the time of drain placement was 70 mL. Drains were left in place for a median 14 days (range 6 to 34 days). Microorganisms were detected in the fluid in 12 of 30 drainage procedures, with Staphylococcus aureus being the most common microorganism. No further intervention was needed in 21 of 30 drainage procedures (70%). However, surgical intervention (removal of expanders) was needed following 6 (20%) drainages, and additional percutaneous drainage procedures were performed following 3 (10%) drainages. CONCLUSION Percutaneous drainage is an effective means of treating post operative fluid collections after expander-based breast reconstruction and can obviate the need for repeat surgery in most cases. PMID:23810309

Endoscopic management of pancreatic fluid collections-revisited

PubMed Central

Nabi, Zaheer; Basha, Jahangeer; Reddy, D Nageshwar

2017-01-01

The development of pancreatic fluid collections (PFC) is one of the most common complications of acute severe pancreatitis. Most of the acute pancreatic fluid collections resolve and do not require endoscopic drainage. However, a substantial proportion of acute necrotic collections get walled off and may require drainage. Endoscopic drainage of PFC is now the preferred mode of drainage due to reduced morbidity and mortality as compared to surgical or percutaneous drainage. With the introduction of new metal stents, the efficiency of endoscopic drainage has improved and the task of direct endoscopic necrosectomy has become easier. The requirement of re-intervention is less with new metal stents as compared to plastic stents. However, endoscopic drainage is not free of adverse events. Severe complications including bleeding, perforation, sepsis and embolism have been described with endoscopic approach to PFC. Therefore, the endoscopic management of PFC is a multidisciplinary affair and involves interventional radiologists as well as GI surgeons to deal with unplanned adverse events and failures. In this review we discuss the recent advances and controversies in the endoscopic management of PFC. PMID:28487603

Lower incidence of complications in endoscopic nasobiliary drainage for hilar cholangiocarcinoma.

PubMed

Kawakubo, Kazumichi; Kawakami, Hiroshi; Kuwatani, Masaki; Haba, Shin; Kudo, Taiki; Taya, Yoko A; Kawahata, Shuhei; Kubota, Yoshimasa; Kubo, Kimitoshi; Eto, Kazunori; Ehira, Nobuyuki; Yamato, Hiroaki; Onodera, Manabu; Sakamoto, Naoya

2016-05-10

To identify the most effective endoscopic biliary drainage technique for patients with hilar cholangiocarcinoma. In total, 118 patients with hilar cholangiocarcinoma underwent endoscopic management [endoscopic nasobiliary drainage (ENBD) or endoscopic biliary stenting] as a temporary drainage in our institution between 2009 and 2014. We retrospectively evaluated all complications from initial endoscopic drainage to surgery or palliative treatment. The risk factors for biliary reintervention, post-endoscopic retrograde cholangiopancreatography (post-ERCP) pancreatitis, and percutaneous transhepatic biliary drainage (PTBD) were also analyzed using patient- and procedure-related characteristics. The risk factors for bilateral drainage were examined in a subgroup analysis of patients who underwent initial unilateral drainage. In total, 137 complications were observed in 92 (78%) patients. Biliary reintervention was required in 83 (70%) patients. ENBD was significantly associated with a low risk of biliary reintervention [odds ratio (OR) = 0.26, 95%CI: 0.08-0.76, P = 0.012]. Post-ERCP pancreatitis was observed in 19 (16%) patients. An absence of endoscopic sphincterotomy was significantly associated with post-ERCP pancreatitis (OR = 3.46, 95%CI: 1.19-10.87, P = 0.023). PTBD was required in 16 (14%) patients, and Bismuth type III or IV cholangiocarcinoma was a significant risk factor (OR = 7.88, 95%CI: 1.33-155.0, P = 0.010). Of 102 patients with initial unilateral drainage, 49 (48%) required bilateral drainage. Endoscopic sphincterotomy (OR = 3.24, 95%CI: 1.27-8.78, P = 0.004) and Bismuth II, III, or IV cholangiocarcinoma (OR = 34.69, 95%CI: 4.88-736.7, P < 0.001) were significant risk factors for bilateral drainage. The endoscopic management of hilar cholangiocarcinoma is challenging. ENBD should be selected as a temporary drainage method because of its low risk of complications.

Kootenai River Fisheries Investigations : Rainbow Trout Recruitment : Period Covered: 1997.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Downs, Chris

1999-02-02

The objective of this study was to determine if juvenile production is limiting the population of rainbow trout Oncorbynchus mykiss in the Idaho reach of the Kootenai River. We used snorkeling and electrofishing techniques to estimate juvenile rainbow trout abundance in, and outmigration from, the Deep, Boulder, and Myrtle creek drainages in Idaho. The total population estimates for the three drainages estimated in 1997 were 30,023; 763; and 235; respectively. A rotary-screw trap was utilized to capture juvenile outmigrants for quantification of age at outmigration and total outmigration from the Deep Creek drainage to the Kootenai River. The total outmigrantmore » estimate for 1997 from the Deep Creek drainage was 38,206 juvenile rainbow trout. Age determination based largely on scales suggests that most juvenile rainbow trout outmigration from the Deep Creek drainage occurs at age-l, during the spring runoff period. Forty-three adult rainbow trout captured in the Deep Creek drainage were tagged with $10.00 reward T-bar anchor tags in 1997. A total of three of these fish were harvested, all in Kootenay Lake, British Columbia. This suggests the possibility of an adfluvial component in the spawning population of the Deep Creek drainage.« less

Recreation use of upper Pemigewasset and Swift River Drainages, New Hampshire

Treesearch

Ronald J. Glass; Gerald S. Walton

1995-01-01

In-stream recreation use of the upper Pemigewasset and Swift River Drainages was estimated by a technique based on modified, stratified sampling. Results are reported by category of stream segment, season, day of week, time of day, and activity. "Weekend and holiday" use exceeded weekday use during spring and fall, but weekdays had the heaviest use during the...

Estimates of recreational stream use in the White River drainage, Vermont

Treesearch

Ronald J. Glass; Gerald Walton; Herbert E. Echelberger; Herbert E. Echelberger

1992-01-01

An observation technique that incorporates Godified, stratified sampling was used to estimate in-stream recreation use in the White River Drainage in Vermont. Results were reported by season, day of week, time of day, kind of activity, and portion of stream. Summer had the highest use followed by spring and fall. Except in fall, weekends and holidays received...

Percutaneous transhepatic drainage of lung abscess through a diaphragmatic fistula caused by a penetrating liver abscess.

PubMed

Taniguchi, Masako; Morita, Satoru; Ueno, Eiko; Hayashi, Mitsutoshi; Ishikawa, Motonao; Mae, Masahiro

2011-11-01

Liver abscesses occurring just below the diaphragm can penetrate or perforate the thoracic cavity, resulting in lung abscess or pyothorax. Although surgical or percutaneous transpleural drainage is often required in such cases, the latter approach has some risks, including hemothorax and bronchopleural fistula formation when the cavity is surrounded by normal lung parenchyma. The present report describes a treatment technique of percutaneous transhepatic drainage through the diaphragmatic fistula to avoid the risks of a transpulmonary approach in a case of lung abscess caused by a penetrating liver abscess.

Clinical application of three-dimensional printing to the management of complex univentricular hearts with abnormal systemic or pulmonary venous drainage.

PubMed

McGovern, Eimear; Kelleher, Eoin; Snow, Aisling; Walsh, Kevin; Gadallah, Bassem; Kutty, Shelby; Redmond, John M; McMahon, Colin J

2017-09-01

In recent years, three-dimensional printing has demonstrated reliable reproducibility of several organs including hearts with complex congenital cardiac anomalies. This represents the next step in advanced image processing and can be used to plan surgical repair. In this study, we describe three children with complex univentricular hearts and abnormal systemic or pulmonary venous drainage, in whom three-dimensional printed models based on CT data assisted with preoperative planning. For two children, after group discussion and examination of the models, a decision was made not to proceed with surgery. We extend the current clinical experience with three-dimensional printed modelling and discuss the benefits of such models in the setting of managing complex surgical problems in children with univentricular circulation and abnormal systemic or pulmonary venous drainage.

Scleral electrocautery and its effects on choroid vessels: implications for subretinal fluid drainage during scleral buckling surgery.

PubMed

Roybal, C Nathaniel; Tsui, Irena; Sanfilippo, Christian; Hubschman, Jean-Pierre

2013-01-01

External drainage of subretinal fluid as part of a scleral buckling procedure rapidly restores the retinal pigment epithelium-neural retina interface in rhegmatogenous retinal detachments but carries the inherent risk of subretinal hemorrhage and retinal incarceration. The authors investigated variations to the technique to reduce the chance of subretinal hemorrhage originating from the choroid. A novel method for needle drainage using electrocautery of the sclerochoroidal layers before puncture was employed. The effect of 0% to 50% scleral electrocautery in a porcine model was investigated. A significant decrease in choroidal vessel diameter and choroidal vessel density at 40% electrocautery was demonstrated. Electrocautery without scleral cut-down before external drainage of subretinal fluid likely decreases the chance of subretinal hemorrhage by decreasing choroidal vascularity. Copyright 2013, SLACK Incorporated.

Managing a chest tube and drainage system.

PubMed

Durai, Rajaraman; Hoque, Happy; Davies, Tony W

2010-02-01

Intercostal drainage tubes (ie, chest tubes) are inserted to drain the pleural cavity of air, blood, pus, or lymph. The water-seal container connected to the chest tube allows one-way movement of air and liquid from the pleural cavity. The container should not be changed unless it is full, and the chest tube should not be clamped unnecessarily. After a chest tube is inserted, a nurse trained in chest-tube management is responsible for managing the chest tube and drainage system. This entails monitoring the chest-tube position, controlling fluid evacuation, identifying when to change or empty the containers, and caring for the tube and drainage system during patient transport. This article provides an overview of indications, insertion techniques, and management of chest tubes. Copyright 2010 AORN, Inc. Published by Elsevier Inc. All rights reserved.

A Specific Mapping Study Using Fluorescence Sentinel Lymph Node Detection in Patients with Intermediate- and High-risk Prostate Cancer Undergoing Extended Pelvic Lymph Node Dissection.

PubMed

Nguyen, Daniel P; Huber, Philipp M; Metzger, Tobias A; Genitsch, Vera; Schudel, Hans H; Thalmann, George N

2016-11-01

Sentinel lymph node (SLN) detection techniques have the potential to change the standard of surgical care for patients with prostate cancer. We performed a lymphatic mapping study and determined the value of fluorescence SLN detection with indocyanine green (ICG) for the detection of lymph node metastases in intermediate- and high-risk patients undergoing radical prostatectomy and extended pelvic lymph node dissection. A total of 42 patients received systematic or specific ICG injections into the prostate base, the midportion, the apex, the left lobe, or the right lobe. We found (1) that external and internal iliac regions encompass the majority of SLNs, (2) that common iliac regions contain up to 22% of all SLNs, (3) that a prostatic lobe can drain into the contralateral group of pelvic lymph nodes, and (4) that the fossa of Marcille also receives significant drainage. Among the 12 patients who received systematic ICG injections, 5 (42%) had a total of 29 lymph node metastases. Of these, 16 nodes were ICG positive, yielding 55% sensitivity. The complex drainage pattern of the prostate and the low sensitivity of ICG for the detection of lymph node metastases reported in our study highlight the difficulties related to the implementation of SNL techniques in prostate cancer. There is controversy about how extensive lymph node dissection (LND) should be during prostatectomy. We investigated the lymphatic drainage of the prostate and whether sentinel node fluorescence techniques would be useful to detect node metastases. We found that the drainage pattern is complex and that the sentinel node technique is not able to replace extended pelvic LND. Copyright © 2016. Published by Elsevier B.V.

Omitting chest tube drainage after thoracoscopic major lung resection.

PubMed

Ueda, Kazuhiro; Hayashi, Masataro; Tanaka, Toshiki; Hamano, Kimikazu

2013-08-01

Absorbable mesh and fibrin glue applied to prevent alveolar air leakage contribute to reducing the length of chest tube drainage, length of hospitalization and the rate of pulmonary complications. This study investigated the feasibility of omitting chest tube drainage in selected patients undergoing thoracoscopic major lung resection. Intraoperative air leakages were sealed with fibrin glue and absorbable mesh in patients undergoing thoracoscopic major lung resection. The chest tube was removed just after tracheal extubation if no air leakages were detected in a suction-induced air leakage test, which is an original technique to confirm pneumostasis. Patients with bleeding tendency or extensive thoracic adhesions were excluded. Chest tube drainage was omitted in 29 (58%) of 50 eligible patients and was used in 21 (42%) on the basis of suction-induced air leakage test results. Male gender and compromised pulmonary function were significantly associated with the failure to omit chest tube drainage (both, P < 0.05). Regardless of omitting the chest tube drainage, there were no adverse events during hospitalization, such as subcutaneous emphysema, pneumothorax, pleural effusion or haemothorax, requiring subsequent drainage. Furthermore, there was no prolonged air leakage in any patients: The mean length of chest tube drainage was only 0.9 days. Omitting the chest tube drainage was associated with reduced pain on the day of the operation (P = 0.046). The refined strategy for pneumostasis allowed the omission of chest tube drainage in the majority of patients undergoing thoracoscopic major lung resection without increasing the risk of adverse events, which may contribute to a fast-track surgery.

[Comparison of the therapeutic effects of PTBD and PTBS in treatment of malignant obstructive jaundice].

PubMed

Bai, Ai-Guo; Zheng, Chuan-Sheng; Zhou, Guo-Feng; Liang, Hui-Min; Feng, Gan-Sheng

2010-06-01

To summarize and compare the short-term and long-term clinical efficacy of percutaneous transhepatic biliary drainage (PTBD) and percutaneous transhepatic biliary stent (PTBS) in the treatment of malignant obstructive jaundice. 210 cases of malignant obstructive jaundice underwent interventional therapy, of which 161 cases of drainage catheters placement and 49 cases of metallic stent implantation. Follow-up information was obtained through telephone review or check-up records. The technical success rate of technique was 100%. At 3 - 5 days after treatment, the serum total bilirubin in 15 metallic stent-treated patients was decreased by (178.04 +/- 42.32) micromol/L, and direct bilirubin by (83.97 +/- 23.63) micromol/L. Compared with those of 28 cases treated with drainage catheters: (95.67 +/- 34.28) micromol/L and (49.84 +/- 28.21) micromol/L, there were statistically significant differences between the two groups (P = 0.017 and P = 0.035). At 6 - 9 days after treatment, the serum total bilirubin in 28 cases of metallic stent group was decreased by (188.22 +/- 79.90) micromol/L, and that in 126 cases of drainage catheter group decreased by (141.39 +/- 65.32) micromol/L. The difference was statistically significant (P = 0.014). But the decline value of direct bilirubin had no significant difference. The median patency period and the median survival time of the drainage catheter group were 60 and 148 days, respectively, those of metallic stent group were 197 days and 245 days. There were statistically significant differences between the two groups (P < 0.05). The results of this study indicate that the short-term and long-term efficacies of metallic stent implantation are better than those of catheter drainage technique.

Chest Tube Drainage of the Pleural Space: A Concise Review for Pulmonologists.

PubMed

Porcel, José M

2018-04-01

Chest tube insertion is a common procedure usually done for the purpose of draining accumulated air or fluid in the pleural cavity. Small-bore chest tubes (≤14F) are generally recommended as the first-line therapy for spontaneous pneumothorax in non-ventilated patients and pleural effusions in general, with the possible exception of hemothoraces and malignant effusions (for which an immediate pleurodesis is planned). Large-bore chest drains may be useful for very large air leaks, as well as post-ineffective trial with small-bore drains. Chest tube insertion should be guided by imaging, either bedside ultrasonography or, less commonly, computed tomography. The so-called trocar technique must be avoided. Instead, blunt dissection (for tubes >24F) or the Seldinger technique should be used. All chest tubes are connected to a drainage system device: flutter valve, underwater seal, electronic systems or, for indwelling pleural catheters (IPC), vacuum bottles. The classic, three-bottle drainage system requires either (external) wall suction or gravity ("water seal") drainage (the former not being routinely recommended unless the latter is not effective). The optimal timing for tube removal is still a matter of controversy; however, the use of digital drainage systems facilitates informed and prudent decision-making in that area. A drain-clamping test before tube withdrawal is generally not advocated. Pain, drain blockage and accidental dislodgment are common complications of small-bore drains; the most dreaded complications include organ injury, hemothorax, infections, and re-expansion pulmonary edema. IPC represent a first-line palliative therapy of malignant pleural effusions in many centers. The optimal frequency of drainage, for IPC, has not been formally agreed upon or otherwise officially established. Copyright©2018. The Korean Academy of Tuberculosis and Respiratory Diseases.

Performance of advanced trauma life support procedures in microgravity

NASA Technical Reports Server (NTRS)

Campbell, Mark R.; Billica, Roger D.; Johnston, Smith L 3rd; Muller, Matthew S.

2002-01-01

BACKGROUND: Medical operations on the International Space Station will emphasize the stabilization and transport of critically injured personnel and so will need to be capable of advanced trauma life support (ATLS). METHODS: We evaluated the ATLS invasive procedures in the microgravity environment of parabolic flight using a porcine animal model. Included in the procedures evaluated were artificial ventilation, intravenous infusion, laceration closure, tracheostomy, Foley catheter drainage, chest tube insertion, peritoneal lavage, and the use of telemedicine methods for procedural direction. RESULTS: Artificial ventilation was performed and appeared to be unaltered from the 1-G environment. Intravenous infusion, laceration closure, percutaneous dilational tracheostomy, and Foley catheter drainage were achieved without difficulty. Chest tube insertion and drainage were performed with no more difficulty than in the 1-G environment due to the ability to restrain patient, operator and supplies. A Heimlich valve and Sorenson drainage system were both used to provide for chest tube drainage collection with minimal equipment, without the risk of atmospheric contamination, and with the capability to auto-transfuse blood drained from a hemothorax. The use of telemedicine in chest tube insertion was demonstrated to be useful and feasible. Peritoneal lavage using a percutaneous technique, although requiring less training to perform, was found to be dangerous in weightlessness due to the additional pressure of the bowel on the anterior abdominal wall creating a high risk of bowel perforation. CONCLUSIONS: The performance of ATLS procedures in microgravity appears to be feasible with the exception of diagnostic peritoneal lavage. Minor modifications to equipment and techniques are required in microgravity to effect surgical drainage in the presence of altered fluid dynamics, to prevent atmospheric contamination, and to provide for the restraint requirements. A parabolic simulation system was developed for equipment and procedure verification, physiological research, and possible crew medical officer training in the future.

Chest Tube Drainage of the Pleural Space: A Concise Review for Pulmonologists

PubMed Central

2018-01-01

Chest tube insertion is a common procedure usually done for the purpose of draining accumulated air or fluid in the pleural cavity. Small-bore chest tubes (≤14F) are generally recommended as the first-line therapy for spontaneous pneumothorax in non-ventilated patients and pleural effusions in general, with the possible exception of hemothoraces and malignant effusions (for which an immediate pleurodesis is planned). Large-bore chest drains may be useful for very large air leaks, as well as post-ineffective trial with small-bore drains. Chest tube insertion should be guided by imaging, either bedside ultrasonography or, less commonly, computed tomography. The so-called trocar technique must be avoided. Instead, blunt dissection (for tubes >24F) or the Seldinger technique should be used. All chest tubes are connected to a drainage system device: flutter valve, underwater seal, electronic systems or, for indwelling pleural catheters (IPC), vacuum bottles. The classic, three-bottle drainage system requires either (external) wall suction or gravity (“water seal”) drainage (the former not being routinely recommended unless the latter is not effective). The optimal timing for tube removal is still a matter of controversy; however, the use of digital drainage systems facilitates informed and prudent decision-making in that area. A drain-clamping test before tube withdrawal is generally not advocated. Pain, drain blockage and accidental dislodgment are common complications of small-bore drains; the most dreaded complications include organ injury, hemothorax, infections, and re-expansion pulmonary edema. IPC represent a first-line palliative therapy of malignant pleural effusions in many centers. The optimal frequency of drainage, for IPC, has not been formally agreed upon or otherwise officially established. PMID:29372629

Comparison of Small Bore Catheter Aspiration and Chest Tube Drainage in the Management of Spontaneous Pneumothorax.

PubMed

Korczyński, P; Górska, K; Nasiłowski, J; Chazan, R; Krenke, R

2015-01-01

Beside standard chest tube drainage other less invasive techniques have been used in the management of patients with an acute episode of spontaneous pneumothorax. The aim of the study was to evaluate the short term effect of spontaneous pneumothorax treatment with small-bore pleural catheter and manual aspiration as compared to large-bore chest tube drainage. Patients with an episode of pneumothorax who required pleural intervention were enrolled in the study and randomly assigned to one of the treatment arms: (1) small-bore pleural catheter (8 Fr) with manual aspiration; (2) standard chest tube drainage (20-24 Fr). Success rate of the first line treatment, duration of catheter or chest tube drainage, and the need for surgical intervention were the outcome measures. The study group included 49 patients (mean age 46.9±21.3 years); with 22 and 27 allocated to small bore manual aspiration and chest tube drainage groups, respectively. There were no significant differences in the baseline characteristics of patients in both therapeutic arms. First line treatment success rates were 64% and 82% in the manual aspiration and chest tube drainage groups, respectively; the difference was insignificant. Median time of treatment with small bore catheter was significantly shorter than conventional chest tube drainage (2.0 vs. 6.0 days; p<0.05). Our results show that treatment of spontaneous pneumothorax with small-bore pleural catheter and manual aspiration might be similarly effective as is chest tube drainage in terms of immediate lung re-expansion.

Complications of Nonoperative Management of High-grade Blunt Hepatic Injuries

DTIC Science & Technology

2005-11-01

cholangiopancreatography (ERCP) and stenting of biliary leaks, and CT scan-guided drainage of hepatic or perihepatic abscesses or biliary collections by...1 B). Stenting was successful in decreasing the biliary leak, but repeat ERCP was required for increased serum bilirubin, pain, and fever...Finally, failure of percutaneous drainage techniques or biliary stenting may require operative intervention. In summary, although patients with high

Thoracoscopic Surgery for Partial Anomalous Pulmonary Venous Connection with Dual Drainage.

PubMed

Fuchigami, Tai; Gabe, Atsushi; Takahashi, Kazuhiro; Nishioka, Masahiko; Akashige, Toru; Nagata, Nobuhiro

2015-10-01

We report our technique for thoracoscopic surgery for a 15-year-old female (body weight, 59 kg) diagnosed with partial anomalous pulmonary venous connection with dual drainage. A large anomalous right lower pulmonary vein (RLPV) was drained into the inferior vena cava and left atrium, along with thoracoscopic ligation and clipping of RLPV and some anomalous hepatic veins. © 2015 Wiley Periodicals, Inc.

Geographic Information Systems Methods for Determining Drainage-Basin Areas, Stream-Buffered Areas, Stream Length, and Land Uses for the Neosho and Spring Rivers in Northeastern Oklahoma

USGS Publications Warehouse

Masoner, Jason R.; March, Ferrella

2006-01-01

Geographic Information Systems have many uses, one of which includes the reproducible computation of environmental characteristics that can be used to categorize hydrologic features. The Oklahoma Department of Wildlife Conservation and the Oklahoma Department of Environmental Quality are investigating Geographic Information Systems techniques to determine partial drainage-basin areas, stream-buffer areas, stream length, and land uses (drainage basin and stream characteristics) in northeastern Oklahoma. The U.S Geological Survey, in cooperation with Oklahoma Department of Wildlife Conservation and the Oklahoma Department of Environmental Quality, documented the methods used to determine drainage-basin and stream characteristics for the Neosho and Spring Rivers above Grand Lake Of the Cherokees in northeastern Oklahoma and calculated the characteristics. The drainage basin and stream characteristics can be used by the Oklahoma Department of Wildlife Conservation and the Oklahoma Department of Environmental Quality to aid in natural-resource assessments.

Dry Stream Reaches in Carbonate Terranes: Surface Indicators of Ground-Water Reservoirs

USGS Publications Warehouse

Brahana, J.V.; Hollyday, E.F.

1988-01-01

In areas where dry stream reaches occur, subsurface drainage successfully competes with surface drainage, and sheet-like dissolution openings have developed parallel to bedding creating the ground-water reservoir. Union Hollow in south-central Tennessee is the setting for a case study that illustrates the application of the dry stream reach technique. In this technique, dry stream reach identification is based on two types of readily acquired information: remotely sensed black and white infrared aerial photography; and surface reconnaissance of stream channel characteristics. Test drilling in Union Hollow subsequent to identification of the dry reach proved that a localized ground-water reservoir was present.

Surgical treatment of chronic pancreatitis and its complications. Comparative analysis of results in 91 patients.

PubMed

Marinov, V; Draganov, K; Gaydarski, R; Katev, N N

2013-01-01

There is a large variety of proposed conservative, invasive, endoscopic and surgical methods for treatment of chronic pancreatitis and its complications. This study presents a comparative analysis of the results from each group of patients subjected to drainage, resection, denervation and other operative techniques for a total of 91 patients with chronic pancreatitis and its complications. Drainage and resection operative techniques yield comparable results in terms of postoperative pain control 93.1% and 100%, perioperative mortality--3.17% and 5.8%, perioperative morbidity--7.9% and 11.7%, respectively. There is a significant increase in the instances of diabetes in the resection group. Right-side semilunar ganglionectomy is a good method for pain control as an accompanying procedure in the course of another main operative technique.

Performance-costs evaluation for urban storm drainage.

PubMed

Baptista, M; Barraud, S; Alfakih, E; Nascimento, N; Fernandes, W; Moura, P; Castro, L

2005-01-01

The design process of urban stormwater systems incorporating BMPs involves more complexity unlike the design of classic drainage systems for which just the technique of pipes is likely to be used. This paper presents a simple decision aid methodology and an associated software (AvDren) concerning urban stormwater systems, devoted to the evaluation and the comparison of drainage scenarios using BMPs according to different technical, sanitary, social environmental and economical aspects. This kind of tool is particularly interesting so as to help the decision makers to select the appropriate alternative and to plan the investments especially for developing countries, with important sanitary problems and severe budget restrictions.

Field Testing of Geophysical Techniques.

DTIC Science & Technology

1981-11-01

influence drainage and groundwater movement in the surrounding area. Presumably, the direction of groundwater movement is to the north and out of the...applicable. Specifically, these additional techniques are: e Audio magneto- telluric (AMT) resistivity * Electromagnetics a Ground-probing radar Both

29 CFR 1910.307 - Hazardous (classified) locations.

Code of Federal Regulations, 2013 CFR

2013-07-01

...; conductor insulation, flexible cords, sealing and drainage, transformers, capacitors, switches, circuit... following are acceptable protection techniques for electric and electronic equipment in hazardous...) Nonincendive circuit. This protection technique is permitted for equipment in Class I, Division 2; Class II...

29 CFR 1910.307 - Hazardous (classified) locations.

Code of Federal Regulations, 2012 CFR

2012-07-01

...; conductor insulation, flexible cords, sealing and drainage, transformers, capacitors, switches, circuit... following are acceptable protection techniques for electric and electronic equipment in hazardous...) Nonincendive circuit. This protection technique is permitted for equipment in Class I, Division 2; Class II...

29 CFR 1910.307 - Hazardous (classified) locations.

Code of Federal Regulations, 2014 CFR

2014-07-01

...; conductor insulation, flexible cords, sealing and drainage, transformers, capacitors, switches, circuit... following are acceptable protection techniques for electric and electronic equipment in hazardous...) Nonincendive circuit. This protection technique is permitted for equipment in Class I, Division 2; Class II...

Characterize the hydraulic behaviour of grate inlet in urban drainage to prevent the urban's flooding

NASA Astrophysics Data System (ADS)

Tellez Alvarez, Jackson David; Gomez, Manuel; Russo, Beniamino; Redondo, Jose M.

2016-04-01

One of the most important problems that have some cities is the urban floods because of poor drainage design. Therefore the systems the drainage do not have the capacity of capture the flow of discharge generated in a rain event and insert it into the drainage network. Even though the two problems that have caught the main attention are the evaluation of the volumes falling in the river basin because extreme rainfall events often lead to urban pluvial flooding being a hydrologic problem and the hydraulic design of the sewer network being a hydraulic problem to limiting capacity of the drainage system, there is an intermediate step between these two processes that is necessary to solve that is the hydraulic behavior of the grate inlet. We need to collect the runoff produced on the city surface and to introduce it in the sewer network. Normally foundry companies provide complete information about drainage grate structural capacity but provide nothing about their hydraulic capacity. This fact can be seen because at the moment does not exist any official regulation at national or international level in this field. It's obvious that, nowadays, there is a great gap in this field at the legislative level owing to the complexity of this field and the modernity of the urban hydrology as science [1]. In essence, we shows the relevance to know the inlet hydraulic interception capacity because surface drainage requires a satisfactory knowledge on storm frequency, gutter flow and above all inlet capacity. In addition, we development an important achievement is the invention and development of techniques for measurement of field velocities in hydraulics engineering applications. Hence knowledge the technological advances in digital cameras with high resolution and high speed found in the environmental, and the advances in image processing techniques, therefore now is a tremendous potential to obtain of behavior of the water surface flow [2]. A novel technique using particle image velocimetry to measure surface flow velocities has been developed and validated with the experiments assays with the grate inlets [3 - 4]. Indeed, the Methodology carried out can become a useful tools to understand the hydraulics behavior of the flow approaching the inlet where the traditional measuring equipment have serious problems and limitations [5 - 6]. References [1] Gómez, M., Macchione, F. and Russo, B. (2006). Inlet systems and risk criteria associated to street runoff application to urban drainage catchments. 27 Corso di aggiornamiento in techniche per la difesa dall'inquinamento. [2] Russo, B., Gómez, M., & Tellez, J. (2013). Methodology to Estimate the Hydraulic Efficiency of Nontested Continuous Transverse Grates. Journal of Irrigation and Drainage Engineering, 139(10), 864-871. doi:10.1061/(ASCE)IR.1943-4774.0000625 [3] DigiFlow. User Guide. (2012), (June). [4] Vila, T., Tellez, J., Sanchez, J.M., Sotillos, L., Diez, M., and Redondo, J.M. (2014). Diffusion in fractal wakes and convective thermoelectric flows. Geophysical Research Abstracts - EGU General Assembly 2014. [5] Tellez, J., Gómez, M., Russo, B. and Redondo, J.M. (2014). A simple technique to measuring surface flow velocity to analyze the behavior of fields velocities in hydraulics engineer applications. Geophysical Research Abstracts - EGU General Assembly 2015. [6] Tellez, J., Gómez, M. and Russo, B. (2015). Técnica para la obtención del campo de velocidad del flujo superficial en proximidad de rejas de alcantarillado. IV Jornadas de Ingeniería del Agua. La precipitación y los procesos erosivos.

Surgery for chronic pancreatitis. Drainage versus resection.

PubMed Central

Proctor, H J; Mendes, O C; Thomas, C G; Herbst, C A

1979-01-01

A retrospective study of 49 patients with chronic obstructive and chronic calcific pancreatitis is presented. All patients were operated upon and underwent either a partial pancreatectomy or internal drainage of the ductal system into a Roux-en-Y loop of jejunum. The criteria for selection of operation are discussed, and the follow-up of the two operative groups is given. In patients selected as described, internal drainage provided better relief of pain and was accomplished with a lower operative mortality and morbidity and with less postoperative pancreatic insufficiency. Images Fig. 1. Fig. 2. Fig. 3. PMID:443918

Transpedicular Curettage and Drainage of Infective Lumbar Spondylodiscitis: Technique and Clinical Results

PubMed Central

Lee, Byung Ho; Lee, Hwan-Mo; Kim, Tae-Hwan; Kim, Hak-Sun; Moon, Eun-Soo; Park, Jin-Oh; Chong, Hyun-Soo

2012-01-01

Background Infective spondylodiscitis usually occurs in patients of older age, immunocompromisation, co-morbidity, and individuals suffering from an overall poor general condition unable to undergo reconstructive anterior and posterior surgeries. Therefore, an alternative, less aggressive surgical method is needed for these select cases of infective spondylodiscitis. This retrospective clinical case series reports our novel surgical technique for the treatment of infective spondylodiscitis. Methods Between January 2005 and July 2011, among 48 patients who were diagnosed with pyogenic lumbar spondylodiscitis or tuberculosis lumbar spondylodiscitis, 10 patients (7 males and 3 females; 68 years and 48 to 78 years, respectively) underwent transpedicular curettage and drainage. The mean postoperative follow-up period was 29 months (range, 7 to 61 months). The pedicle screws were inserted to the adjacent healthy vertebrae in the usual manner. After insertion of pedicle screws, the drainage pedicle holes were made through pedicles of infected vertebra(e) in order to prevent possible seeding of infective emboli to the healthy vertebra, as the same instruments and utensils are used for both pedicle screws and the drainage holes. A minimum of 15,000 mL of sterilized normal saline was used for continuous irrigation through the pedicular pathways until the drained fluid looked clear. Results All patients' symptoms and inflammatory markers significantly improved clinically between postoperative 2 weeks and postoperative 3 months, and they were satisfied with their clinical results. Radiologically, all patients reached the spontaneous fusion between infected vertebrae and 3 patients had the screw pulled-out but they were clinically tolerable. Conclusions We suggest that our method of transpedicular curettage and drainage is a useful technique in regards to the treatment of infectious spondylodiscitic patients, who could not tolerate conventional combined anterior and posterior surgery due to multiple co-morbidities, multiple level infectious lesions and poor general condition. PMID:22949951

Management of chest drainage tubes after lung surgery.

PubMed

Satoh, Yukitoshi

2016-06-01

Since chest tubes have been routinely used to drain the pleural space, particularly after lung surgery, the management of chest tubes is considered to be essential for the thoracic surgeon. The pleural drainage system requires effective drainage, suction, and water-sealing. Another key point of chest tube management is that a water seal is considered to be superior to suction for most air leaks. Nowadays, the most common pleural drainage device attached to the chest tube is the three-bottle system. An electronic chest drainage system has been developed that is effective in standardizing the postoperative management of chest tubes. More liberal use of digital drainage devices in the postoperative management of the pleural space is warranted. The removal of chest tubes is a common procedure occurring almost daily in hospitals throughout the world. Extraction of the tube is usually done at the end of full inspiration or at the end of full expiration. The tube removal technique is not as important as how it is done and the preparation for the procedure. The management of chest tubes must be based on careful observation, the patient's characteristics, and the operative procedures that had been performed.

Adaptation Options for Land Drainage Systems Towards Sustainable Agriculture and Environment: A Czech Perspective

NASA Astrophysics Data System (ADS)

Kulhavý, Zbyněk; Fučík, Petr

2015-04-01

In this paper, issues of agricultural drainage systems are introduced and discussed from the views of their former, current and future roles and functioning in the Czech Republic (CR). A methodologically disparate survey was done on thirty-nine model localities in CR with different intensity and state of land drainage systems, aimed at description of commonly occurred problems and possible adaptations of agricultural drainage as perceived by farmers, land owners, landscape managers or by protective water management. The survey was focused on technical state of drainage, fragmentation of land ownership within drained areas as well as on possible conflicts between agricultural and environmental interests in a landscape. Achieved results confirmed that there is obviously an increasing need to reassess some functions of prevailingly single-purpose agricultural drainage systems. Drainage intensity and detected unfavourable technical state of drainage systems as well as the risks connected with the anticipated climate change from the view of possible water scarcity claims for a complex solution. An array of adaptation options for agricultural drainage systems is presented, aiming at enhancement of water retention time and improvement of water quality. It encompasses additional flow-controlling measures on tiles or ditches, or facilities for making selected parts of a drainage system inoperable in order to retain or slow down the drainage runoff, to establish water accumulation zones and to enhance water self-cleaning processes. However, it was revealed that the question of landowner parcels fragmentation on drained land in CR would dramatically complicate design and realization of these measures. Presented solutions and findings are propounded with a respect to contemporary and future state policies and international strategies for sustainable agriculture, water management and environment.

Workshop on sediment budgets and routing in forested drainage basins: proceedings.

Treesearch

Frederick J. Swanson; Richard J. Janda; Thomas Dunne; Douglas N. Swanston

1982-01-01

Sediment budgets quantify the transport and storage of soil and sediment in drainage basins or smaller landscape units. Studies of sediment routing deal with the overall movement of soil and sediment through a series of landscape units. The 14 papers and 5 summaries from discussion groups in this volume report results of sediment budget and routing studies conducted...

Systematic review of efficacy for manual lymphatic drainage techniques in sports medicine and rehabilitation: an evidence-based practice approach.

PubMed

Vairo, Giampietro L; Miller, Sayers John; McBrier, Nicole M; Buckley, William E

2009-01-01

Manual therapists question integrating manual lymphatic drainage techniques (MLDTs) into conventional treatments for athletic injuries due to the scarcity of literature concerning musculoskeletal applications and established orthopaedic clinical practice guidelines. The purpose of this systematic review is to provide manual therapy clinicians with pertinent information regarding progression of MLDTs as well as to critique the evidence for efficacy of this method in sports medicine. We surveyed English-language publications from 1998 to 2008 by searching PubMed, PEDro, CINAHL, the Cochrane Library, and SPORTDiscus databases using the terms lymphatic system, lymph drainage, lymphatic therapy, manual lymph drainage, and lymphatic pump techniques. We selected articles investigating the effects of MLDTs on orthopaedic and athletic injury outcomes. Nine articles met inclusion criteria, of which 3 were randomized controlled trials (RCTs). We evaluated the 3 RCTs using a validity score (PEDro scale). Due to differences in experimental design, data could not be collapsed for meta-analysis. Animal model experiments reinforce theoretical principles for application of MLDTs. When combined with concomitant musculoskeletal therapy, pilot and case studies demonstrate MLDT effectiveness. The best evidence suggests that efficacy of MLDT in sports medicine and rehabilitation is specific to resolution of enzyme serum levels associated with acute skeletal muscle cell damage as well as reduction of edema following acute ankle joint sprain and radial wrist fracture. Currently, there is limited high-ranking evidence available. Well-designed RCTs assessing outcome variables following implementation of MLDTs in treating athletic injuries may provide conclusive evidence for establishing applicable clinical practice guidelines in sports medicine and rehabilitation.

Twist-Drill or Burr Hole Craniostomy for Draining Chronic Subdural Hematomas: How to Choose It for Chronic Subdural Hematoma Drainage

PubMed Central

Lee, Seong-Jong; Im, Soo Bin

2016-01-01

Objective Although twist-drill craniostomy (TDC) has a number of procedural advantages and an equivalent outcome compared to burr hole craniostomy (BHC) for the treatment of chronic subdural hematomas (CSDHs), the latter technique remains the preferred method. We analyzed symptomatic CSDHs in whom TDC at the pre-coronal suture entry point (PCSEP) was the primary method for hematoma drainage and BHC on the parietal was the secondary option. Methods CSDHs in 86 consecutive patients were included. TDC at the PCSEP, which is 1 cm anterior to coronal suture at the level of the superior temporal line, was the primary operational technique when the hematoma thickness was suitable, and BHC was performed via the parietal when TDC was unreasonable or failed. The clinical feasibility and outcomes of these approaches were analyzed. Results Of the 86 patients, 68 (79.1%) were treated by TDC, and 18 (20.9%) by BHC. All patients showed improvements in their symptoms after hematoma drainage. Neither morbidity nor mortality was associated with either technique, and there were no differences in drainage days between the groups. Ten patients had bilateral hematomas and were treated using TDC. Two patients were not sufficiently treated by TDC and, as a result, BHC was applied. Only six hematomas (7% of 86 hematomas) exhibited insufficient thickness on the computed tomography to perform TDC. Conclusion When the hematoma was thick enough, a majority of the CSDHs were drained using TDC at the PCSEP as the first procedure, which was especially useful for bilateral hematomas and in elderly patients. PMID:27857917

Twist-Drill or Burr Hole Craniostomy for Draining Chronic Subdural Hematomas: How to Choose It for Chronic Subdural Hematoma Drainage.

PubMed

Lee, Seong-Jong; Hwang, Sun-Chul; Im, Soo Bin

2016-10-01

Although twist-drill craniostomy (TDC) has a number of procedural advantages and an equivalent outcome compared to burr hole craniostomy (BHC) for the treatment of chronic subdural hematomas (CSDHs), the latter technique remains the preferred method. We analyzed symptomatic CSDHs in whom TDC at the pre-coronal suture entry point (PCSEP) was the primary method for hematoma drainage and BHC on the parietal was the secondary option. CSDHs in 86 consecutive patients were included. TDC at the PCSEP, which is 1 cm anterior to coronal suture at the level of the superior temporal line, was the primary operational technique when the hematoma thickness was suitable, and BHC was performed via the parietal when TDC was unreasonable or failed. The clinical feasibility and outcomes of these approaches were analyzed. Of the 86 patients, 68 (79.1%) were treated by TDC, and 18 (20.9%) by BHC. All patients showed improvements in their symptoms after hematoma drainage. Neither morbidity nor mortality was associated with either technique, and there were no differences in drainage days between the groups. Ten patients had bilateral hematomas and were treated using TDC. Two patients were not sufficiently treated by TDC and, as a result, BHC was applied. Only six hematomas (7% of 86 hematomas) exhibited insufficient thickness on the computed tomography to perform TDC. When the hematoma was thick enough, a majority of the CSDHs were drained using TDC at the PCSEP as the first procedure, which was especially useful for bilateral hematomas and in elderly patients.

Vaccum drainage system application in the management of operation-related non-regional epidural hematoma

PubMed Central

2013-01-01

Background Epidural intracranial hematoma is one of the most common complications of surgeries for intracranial tumors. The non-regional epidural hematoma is related to severe fluctuation of the intracranial pressure during the operation. The traditional management of hematoma evacuation through craniotomy is time-consuming and may aggravate intracranial pressure imbalance, which causes further complications. We designed a method using vaccum epidural drainage system, and tried to evaluate advantage and the disadvantage of this new technique. Methods Seven patients of intracranial tumors were selected. All of the patients received tumor resection and intra-operative non-regional epidural hematoma was confirmed through intra-operative ultrasound or CT scan. The vaccum drainage system was applied. Another ten patients who received craniotomy for intra-operative non-regional epidural hematoma evacuation were selected as comparison. Regular tests, like serial CT scan, were performed afterward to evaluate the effectiveness and to help deciding when to remove the drainage system. Results The vaccum drainage method was effective in epidual hemotoma clearance and prevented recurrent epidural hemorrhage. The drainage systems were removed within 4 days. All of the patients recovered well. No complications related to the drainage system were observed. Conclusions Compared to the traditional craniotomy, the new method of epidural hemoatoma management using vaccum epidural drainage system proved to be as effective in hematoma clearance, and was less-invasive and easier to perform, with less complication, shorter hospitalization, less economic burden, and better prognosis. PMID:23842198

Impact of climate change on acid mine drainage generation and contaminant transport in water ecosystems of semi-arid and arid mining areas

NASA Astrophysics Data System (ADS)

Anawar, Hossain Md.

Disposal of untreated and treated mining wastes and tailings exerts a significant threat and hazard for environmental contamination including groundwater, surface water, wetlands, land, food chain and animals. In order to facilitate remediation techniques, it is important to understand the oxidation of sulfidic minerals, and the hydrolysis of the oxidation products that result in production of acid mine drainage (AMD), toxic metals, low pH, SO42- and Fe. This review has summarized the impacts of climate change on geochemical reactions, AMD generation, and water quality in semi-arid/arid mining environments. Besides this, the study included the effects of hydrological, seasonal and climate change on composition of AMD, contaminant transport in watersheds and restoration of mining sites. Different models have different types of limitations and benefits that control their adaptability and suitability of application in various mining environments. This review has made a comparative discussion of a few most potential and widely used reactive transport models that can be applied to simulate the effect of climate change on sulfide oxidation and AMD production from mining waste, and contaminant transport in surface and groundwater systems.

Novel use of pleural ultrasound can identify malignant entrapped lung prior to effusion drainage.

PubMed

Salamonsen, Matthew R; Lo, Ada K C; Ng, Arnold C T; Bashirzadeh, Farzad; Wang, William Y S; Fielding, David I K

2014-11-01

The presence of entrapped lung changes the appropriate management of malignant pleural effusion from pleurodesis to insertion of an indwelling pleural catheter. No methods currently exist to identify entrapped lung prior to effusion drainage. Our objectives were to develop a method to identify entrapped lung using tissue movement and deformation (strain) analysis with ultrasonography and compare it to the existing technique of pleural elastance (PEL). Prior to drainage, 81 patients with suspected malignant pleural effusion underwent thoracic ultrasound using an echocardiogram machine. Images of the atelectatic lower lobe were acquired during breath hold, allowing motion and strain related to the cardiac impulse to be analyzed using motion mode (M mode) and speckle-tracking imaging, respectively. PEL was measured during effusion drainage. The gold-standard diagnosis of entrapped lung was the consensus opinion of two interventional pulmonologists according to postdrainage imaging. Participants were randomly divided into development and validation sets. Both total movement and strain were significantly reduced in entrapped lung. Using data from the development set, the area under the receiver-operating curves for the diagnosis of entrapped lung was 0.86 (speckle tracking), 0.79 (M mode), and 0.69 (PEL). Using respective cutoffs of 6%, 1 mm, and 19 cm H2O on the validation set, the sensitivity/specificity was 71%/85% (speckle tracking), 50%/85% (M mode), and 40%/100% (PEL). This novel ultrasound technique can identify entrapped lung prior to effusion drainage, which could allow appropriate choice of definitive management (pleurodesis vs indwelling catheter), reducing the number of interventions required to treat malignant pleural effusion.

Does pilonidal abscess heal quicker with off-midline incision and drainage?

PubMed

Webb, P M; Wysocki, A P

2011-06-01

No clinical trials have been done to guide the surgeon in the optimal technique of draining a pilonidal abscess. The aim of our study was to investigate whether the location of the incision influences wound healing. Electronic records from the surgical database at our 200-bed district general hospital were reviewed for operative technique (midline vs. lateral) for patients who underwent incision and drainage for acute pilonidal abscess between January 2003 and February 2010. These patients were admitted from the Emergency Department with a pilonidal abscess, underwent operative drainage, and returned for follow-up. The main outcome measure was wound healing time. Two hundred and forty-three pilonidal abscesses were drained, 134 with a lateral and 74 with a midline incision. All patients underwent simple longitudinal incision. No patient underwent de-roofing, marsupialisation, or closure. Forty-eight patients with midline drainage who returned for follow-up were matched for gender, age, and microbiology culture results with patients who underwent lateral drainage. Almost all were drained under general anesthesia with a median postoperative stay of 1 day. The overall length of follow-up was the same in both groups (P = 0.13). Abscesses that did not heal were followed-up for the same period of time irrespective of incision type (P = 0.48). Abscesses that healed after midline incision took approximately 3 weeks longer than those drained via a lateral incision (P = 0.02). Our study has limitations since it was a retrospective study that did not capture patients whose abscess drained spontaneously or were drained in the emergency department. Pilonidal abscess should be drained away from the midline.

[Treatment of the first episode of spontaneous pneumothorax].

PubMed

Moubachir, H; Zaghba, N; Benjelloun, H; Bakhatar, A; Yassine, N

2016-11-01

The management of a first episode of spontaneous pneumothorax is controversial and the best technique to be used as an initial intervention, aspiration or intercostal drainage, is still debated. We present a retrospective case series during two and a half consecutive years describing the immediate management of spontaneous pneumothoraces, comparing aspiration versus thoracic drainage. One hundred and thirty-three clinical files from patients with spontaneous pneumothoraces were analyzed (17 primary and 116 secondary). The pneumothoraces were of varying size and different etiologies. Patients were initially treated with simple aspiration in 68 cases, with an immediate success rate of 37.5%, intercostal drainage in 49 cases, and by rest alone in 16 cases. In case of secondary pneumothorax, aspiration appeared to offer advantages as an initial strategy over intercostal drainage in terms of hospital stay (11 versus 22 days), and with significant effectiveness (37.5%). Copyright © 2016 SPLF. Published by Elsevier Masson SAS. All rights reserved.

Genetic structure of Columbia River redband trout populations in the Kootenai River drainage, Montana, revealed by microsatellite and allozyme loci

USGS Publications Warehouse

Knudsen, K.-L.; Muhlfeld, C.C.; Sage, G.K.; Leary, R.F.

2002-01-01

We describe the genetic divergence among 10 populations of redband trout Oncorhynchus mykiss gairdneri from the upper Columbia River drainage. Resident redband trout from two watersheds in the Kootenai River drainage and hatchery stocks of migratory Kamloops redband trout from Kootenay Lake, British Columbia, were analyzed using allele frequency data from microsatellite and allozyme loci. The Kamloops populations have significantly different allele frequencies from those of the Kootenai River drainage. Of the total genetic variation detected in the resident redband trout, 40.7% (microsatellites) and 15.5% (allozymes) were due to differences between populations from the two Kootenai River watersheds. The divergence among populations within each watershed, however, was less than 3.5% with both techniques. Our data indicate that watershed-specific broodstocks of redband trout are needed by fisheries managers for reintroduction or the supplementation of populations at risk of extinction.

Klippel-Trenaunay syndrome complicated by ascites and vaginal lymphatic drainage in adolescence: a case report.

PubMed

Scribner, Dennis R; Lara-Torre, Eduardo; Heineck, Robert J; Weiss, Patrice M

2012-12-01

Klippel-Trenaunay syndrome is a rare disease characterized by capillary malformationsand soft tissue and bony hypertrophy and atypical varicosities. Management of this syndrome is focused primarily on treatment of the complications that arise from these malformations. Ascites and lymphedema are two of the more common complications in these patients. A 15-year-old female with Klippel-Trenaunay syndrome presented with chylous ascites, vaginal drainage, and unilateral lower extremity lymphedema. Treatment included dilation, hysteroscopy and curettage, and laparoscopic evacuation of abdomino-pelvic ascites with resolution of symptoms for 32 months. Repeat laparoscopic drainage was successful and remains symptom free after 12 months. Vaginal drainage of chylous ascites is a rare complication from Klippel-Trenaunay syndrome and can be successfully managed by techniques to remove abdomino-pelvic ascites. Copyright © 2012 North American Society for Pediatric and Adolescent Gynecology. Published by Elsevier Inc. All rights reserved.

Regression Equations for Monthly and Annual Mean and Selected Percentile Streamflows for Ungaged Rivers in Maine

USGS Publications Warehouse

Dudley, Robert W.

2015-12-03

The largest average errors of prediction are associated with regression equations for the lowest streamflows derived for months during which the lowest streamflows of the year occur (such as the 5 and 1 monthly percentiles for August and September). The regression equations have been derived on the basis of streamflow and basin characteristics data for unregulated, rural drainage basins without substantial streamflow or drainage modifications (for example, diversions and (or) regulation by dams or reservoirs, tile drainage, irrigation, channelization, and impervious paved surfaces), therefore using the equations for regulated or urbanized basins with substantial streamflow or drainage modifications will yield results of unknown error. Input basin characteristics derived using techniques or datasets other than those documented in this report or using values outside the ranges used to develop these regression equations also will yield results of unknown error.

[Pancreaticojejunal anastomosis. Indication, technique and results].

PubMed

Gebhardt, C

2001-01-01

Pancreaticojejunal anastomosis. Indication, technique and results. Pancreaticojejunal anastomoses are performed for the treatment of chronic pancreatitis and after resection of pancreatic carcinomas. In chronic pancreatitis by drainage procedures (Partington-Rochelle and Puestow-Gillesby) one can expect good long term results, if the diameter of the pancreatic duct is at least 1 cm and the length of the anastomosis 6 cm. The duodenumpreserving head resection (Beger or Frey) is a combination of resection and drainage and is significant in the therapy of inflammatory head processes. In the surgical treatment of pancreatic carcinomas pancreaticojejunostomies are applied after head resection (Whipple-, pyloruspreserving modification). The end-to-side mucosa-mucosa anastomosis offers the best results concerning postoperativ complications and mortality rates.

Application of seepage flow models to a drainage project in fractured rock

NASA Astrophysics Data System (ADS)

Gmünder, Ch.; Arn, Th.

1993-04-01

Various theoretical approaches are used to model groundwater flow in fractured rock. This paper presents the application of several approaches to the restoration of the drainage of Rofla tunnel, Grisons, Switzerland. In this tunnel it became necessary to take measures against the washing out of calcium carbonates from the tunnel lining cement, because the calcium carbonate clogged up the existing drainage tubes leading to increased rock water pressures on the inside arch of the tunnel. Drainage boreholes were drilled on a section of the tunnel and their influence on the water pressures was monitored. On the basis of the geological survey different seepage flow models were established to reproduce the measured water pressures. The models were then used to predict the future water pressures acting on the tunnel lining after restoration. Thus, the efficacy of the different drainage proposals could be predicted and therefore optimised. Finally, the accuracy of the predictions is discussed and illustrated using the measurements in the test section.

Current Status of Percutaneous Transhepatic Biliary Drainage in Palliation of Malignant Obstructive Jaundice: A Review

PubMed Central

Chandrashekhara, SH; Gamanagatti, S; Singh, Anuradha; Bhatnagar, Sushma

2016-01-01

Malignancies leading to obstructive jaundice present too late to perform surgery with a curative intent. Due to inexorably progressing hyperbilirubinemia with its consequent deleterious effects, drainage needs to established even in advanced cases. Percutaneous transhepatic biliary drainage (PTBD) and endoscopic retrograde cholangiopancreatography (ERCP) are widely used palliative procedures each with its own merits and lacunae. With the current state-of-the-art PTBD technique consequent upon procedural and hardware improvement, it is equaling ERCP regarding technical success and complications. In addition, there is a reduction in immediate procedure-related mortality with proven survival benefit. Nonetheless, it is the only imminent lifesaving procedure in cholangitis and sepsis. PMID:27803558

Recurrent Hydrocoele

PubMed Central

Parks, Kelly; Leung, Lawrence

2013-01-01

Hydrocele is a common cause of scrotal swelling in general practice and is caused by a patent space in the tunica vaginalis. Treatment is often conservative unless the hydrocele grows to a critical size that leads to discomfort or difficulty in walking, in which case drainage is necessary. Depending on the communication of the tunica vaginalis with the peritoneal cavity and other coexistent morbidities, hydrocoele may recur despite repeated drainage posing a problem to management in general practice. We hereby presented a 72-year male with a huge hydrocoele that recurred despite repeated drainage and hernia sac repair, arousing thoughts on this subject and discussions as to the most appropriate management. PMID:24479061

Half versus full vacuum suction drainage after modified radical mastectomy for breast cancer- a prospective randomized clinical trial[ISRCTN24484328

PubMed Central

Chintamani; Singhal, Vinay; Singh, JP; Bansal, Anju; Saxena, Sunita

2005-01-01

Background Suction drains are routinely used after modified radical mastectomy and are an important factor contributing to increased hospital stay as the patients are often discharged only after their removal. Amongst various factors that influence the amount of postoperative drainage, the negative suction pressure applied to the drain has been reported to be of great significance. While a high negative suction pressure is expected to drain the collection and reduce the dead space promptly, it may also prevent the leaking lymphatics from closing and lead to increased drainage from the wound. Against this background a prospective randomized clinical study was conducted to compare the amount and duration of drainage between a half negative suction and full vacuum suction drainage in patients following modified radical mastectomy. The associated postoperative morbidity was also compared between the two groups. Methods 85 FNAC (fine needle aspiration cytology) proven cases of locally advanced breast cancer were randomized. (Using randomly ordered sealed envelops, which were opened immediately before the closure of the wound) in to 50 patients with full vacuum suction (pressure = 700 g/m2) and 35 cases in to half vacuum suction drainage (pressure = 350 g/m2) groups. The two groups were comparable in respect of age, weight, and technique of operation and extent of axillary dissection. Surgery was performed by the same surgical team comprising of five surgeons (two senior and three resident surgeons) using a standardized technique with electrocautery. External compression dressing was provided over the axilla for first 48 hrs and following that patients were encouraged to do active and passive shoulder exercises. The outcomes measured were postoperative morbidity and the length of hospital stay. Statistical methods used: Descriptive studies were performed with SPSS version 10 and group characteristics were compared using student t-test. Results Half vacuum suction drains were removed earlier than the full suction vacuum suction drains. There was no significant difference in the incidence of seroma formation in the two groups and there was a significant reduction in the total hospital stay in patients with half vacuum suction drainage systems as compared to the full suction drainage group (p < 0.001) without any added morbidity. Conclusions Half negative suction drains provide an effective compromise between no suction and full or high suction drainage after modified radical mastectomy by reducing the hospital stay and the post operative morbidity including post operative seromas. PMID:15676064

Hydrology

ERIC Educational Resources Information Center

Sharp, John M.

1977-01-01

Lists many recent research projects in hydrology, including flow in fractured media, improvements in remote-sensing techniques, effects of urbanization on water resources, and developments in drainage basins. (MLH)

Technique for simulating peak-flow hydrographs in Maryland

USGS Publications Warehouse

Dillow, Jonathan J.A.

1998-01-01

The efficient design and management of many bridges, culverts, embankments, and flood-protection structures may require the estimation of time-of-inundation and (or) storage of floodwater relating to such structures. These estimates can be made on the basis of information derived from the peak-flow hydrograph. Average peak-flow hydrographs corresponding to a peak discharge of specific recurrence interval can be simulated for drainage basins having drainage areas less than 500 square miles in Maryland, using a direct technique of known accuracy. The technique uses dimensionless hydrographs in conjunction with estimates of basin lagtime and instantaneous peak flow. Ordinary least-squares regression analysis was used to develop an equation for estimating basin lagtime in Maryland. Drainage area, main channel slope, forest cover, and impervious area were determined to be the significant explanatory variables necessary to estimate average basin lagtime at the 95-percent confidence interval. Qualitative variables included in the equation adequately correct for geographic bias across the State. The average standard error of prediction associated with the equation is approximated as plus or minus (+/-) 37.6 percent. Volume correction factors may be applied to the basin lagtime on the basis of a comparison between actual and estimated hydrograph volumes prior to hydrograph simulation. Three dimensionless hydrographs were developed and tested using data collected during 278 significant rainfall-runoff events at 81 stream-gaging stations distributed throughout Maryland and Delaware. The data represent a range of drainage area sizes and basin conditions. The technique was verified by applying it to the simulation of 20 peak-flow events and comparing actual and simulated hydrograph widths at 50 and 75 percent of the observed peak-flow levels. The events chosen are considered extreme in that the average recurrence interval of the selected peak flows is 130 years. The average standard errors of prediction were +/- 61 and +/- 56 percent at the 50 and 75 percent of peak-flow hydrograph widths, respectively.

Randomized, controlled pilot study comparing large-volume paracentesis using wall suction and traditional glass vacuum bottle methods.

PubMed

Konerman, Monica A; Price, Jennifer; Torres, Dawn; Li, Zhiping

2014-09-01

Large-volume paracentesis (LVP) can be time and labor intensive depending on the amount of ascites removed and the method of drainage. Wall suction has been adopted as the preferred method of drainage at many centers, though the safety and benefits of this technique have not been formally evaluated. The primary objective of this study was to define the cost and time savings of wall suction over the traditional glass vacuum bottle method for ascites drainage. The secondary objective was to compare the safety profile and patient satisfaction using these two techniques. We conducted a randomized, controlled pilot study of the wall suction versus vacuum bottle methods for LVP in hospitalized patients. All LVPs were performed under ultrasound guidance by a single proceduralist. Patients with at least 4 liters removed received 25% intravenous albumin, 8 g/liter fluid removed. Demographic, clinical characteristics, and procedure details were recorded. Laboratory and hemodynamic data were recorded for 24 h prior to and 24-48 h post LVP. An electronic chart review was conducted to evaluate procedure-related complications. Data were compared using Fisher's exact test, t test, or Mann-Whitney U test. Thirty-four patients were randomized to wall suction at 200 mmHg (n = 17) or glass vacuum bottle drainage (n = 17). Wall suction was significantly faster and less costly than vacuum bottle drainage (7 versus 15 min, p = 0.002; $4.59 versus $12.73, p < 0.001). There were no differences in outcomes at 24 and 48 h post LVP, or at 60-day follow up. Performing LVP using wall suction resulted in significantly shorter procedure time and supply cost savings. There were no differences in outcomes between the groups, suggesting equivalent safety, though larger studies powered to detect small differences are needed. Given its efficiency, convenience, and cost effectiveness, wall suction may be a superior method of ascites drainage for LVP.

Geochemistry of dissolved trace elements and heavy metals in the Dan River Drainage (China): distribution, sources, and water quality assessment.

PubMed

Meng, Qingpeng; Zhang, Jing; Zhang, Zhaoyu; Wu, Tairan

2016-04-01

Dissolved trace elements and heavy metals in the Dan River drainage basin, which is the drinking water source area of South-to-North Water Transfer Project (China), affect large numbers of people and should therefore be carefully monitored. To investigate the distribution, sources, and quality of river water, this study integrating catchment geology and multivariate statistical techniques was carried out in the Dan River drainage from 99 river water samples collected in 2013. The distribution of trace metal concentrations in the Dan River drainage was similar to that in the Danjiangkou Reservoir, indicating that the reservoir was significantly affected by the Dan River drainage. Moreover, our results suggested that As, Sb, Cd, Mn, and Ni were the major pollutants. We revealed extremely high concentrations of As and Sb in the Laoguan River, Cd in the Qingyou River, Mn, Ni, and Cd in the Yinhua River, As and Sb in the Laojun River, and Sb in the Dan River. According to the water quality index, water in the Dan River drainage was suitable for drinking; however, an exposure risk assessment model suggests that As and Sb in the Laojun and Laoguan rivers could pose a high risk to humans in terms of adverse health and potential non-carcinogenic effects.

Is the recurrence rate of chronic subdural hematomas dependent on the duration of drainage?

PubMed

Kale, Aydemir; Öz, İbrahim İlker; Gün, Eren Görkem; Kalaycı, Murat; Gül, Şanser

2017-05-01

Chronic subdural hematoma (CSDH) is the most frequent type of intracranial hemorrhage which especially affects the elderly. Various surgical techniques have been reported for CSDH treatment; optimal treatment methods are still controversial. In this study, the effects of long drainage durations on results and recurrences were investigated in patients on whom closed system drainage with burr hole craniotomy was applied due to CSDH. 90 patients with 105 CSDH were operated between 2008 and 2016. Patients were divided into two groups based on the duration of drainage. Group A (n = 40) was determined as 2-4 days of closed-system drainage, while Group B (n = 50) was recorded as 5-7 days of closed-system drainage. Recurrence was defined as accumulation of blood in the operation area and recurrence of symptoms within the monitoring period of six months. Recurrence was observed in 7 (15.6) of the Group A patients and 2 (3.3%) of the Group B patients. There was a statistically significant difference between groups in terms of recurrence rate (p = 0.04). Postoperative thickness of hematoma was measured in the first month follow-up computerized tomography. There was a statistically significant difference between groups in terms of postoperative thickness of residual hematoma (p = 0.05). 2-4 days of closed system drainage following burr hole craniotomy is an effective and reliable choice of treatment in CSDH. Nevertheless, increasing the duration of drainage to 5-7 days provided better results without increasing the risk of complication.

Hydrologic connectivity: Quantitative assessments of hydrologic-enforced drainage structures in an elevation model

USGS Publications Warehouse

Poppenga, Sandra K.; Worstell, Bruce B.

2016-01-01

Elevation data derived from light detection and ranging present challenges for hydrologic modeling as the elevation surface includes bridge decks and elevated road features overlaying culvert drainage structures. In reality, water is carried through these structures; however, in the elevation surface these features impede modeled overland surface flow. Thus, a hydrologically-enforced elevation surface is needed for hydrodynamic modeling. In the Delaware River Basin, hydrologic-enforcement techniques were used to modify elevations to simulate how constructed drainage structures allow overland surface flow. By calculating residuals between unfilled and filled elevation surfaces, artificially pooled depressions that formed upstream of constructed drainage structure features were defined, and elevation values were adjusted by generating transects at the location of the drainage structures. An assessment of each hydrologically-enforced drainage structure was conducted using field-surveyed culvert and bridge coordinates obtained from numerous public agencies, but it was discovered the disparate drainage structure datasets were not comprehensive enough to assess all remotely located depressions in need of hydrologic-enforcement. Alternatively, orthoimagery was interpreted to define drainage structures near each depression, and these locations were used as reference points for a quantitative hydrologic-enforcement assessment. The orthoimagery-interpreted reference points resulted in a larger corresponding sample size than the assessment between hydrologic-enforced transects and field-surveyed data. This assessment demonstrates the viability of rules-based hydrologic-enforcement that is needed to achieve hydrologic connectivity, which is valuable for hydrodynamic models in sensitive coastal regions. Hydrologic-enforced elevation data are also essential for merging with topographic/bathymetric elevation data that extend over vulnerable urbanized areas and dynamic coastal regions.

Simulation of the erosion and drainage development of Loess surface based on GIS

NASA Astrophysics Data System (ADS)

Wang, Chun; Tang, Guoan; Ge, Shanshan; Li, Zhanbin; Zhou, Jieyu

2006-10-01

The research probes into the temporal-spatial process of drainage development of Loess Plateau on the basis of a carefully designed experiment. In the experiment, the development of a simulated loess watershed is tested under the condition of lab-simulated rainfall. A close-range photogrammetry survey is employed to establish a series of high precision and resolution DEM (Digit Elevation Model) of the simulated loess surface. Based on the established DEM, the erosion loss, the slope distribution, the topographic index , the gully-brink, and the drainage networks are all derived and discussed through comparison analysis and experimental validation. All the efforts aim at revealing the process and mechanism of erosion and drainage development of loess surface .This study demonstrates: 1) the stimulation result can effectively reflect the truth if those experimental conditions, i.e. loess soil structure, simulated rainfall, are adjusted in accord with true situation; 2) the remarkable character of the erosion and drainage up-growth of loess surface include the drainage traced to the source, the increased of the drainage's density, the enlarged of gully, the durative variety of multiple terrain factor's mean value and its distribution, such as slope and topographic index; 3) The slope spectrum is the more felicitous terrain factor for depicting the erosion and drainage development of loess surface, including the rule of erosion and evolution process. It is the new way and mean for studying the loess physiognomy.

Environmental Development Plan (EDP). Enhanced gas recovery, FY 1977

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1978-03-01

This Enhanced Gcs Recovery EDP addresses the environmental impacts of enhanced gas recovery processes in shale and sandstone, methane drainage from coalbeds, and methane recovery from geopressured aquifers. The EDP addresses planning in two basic areas: environmental research and environmental assessment. Environmental research can be categorized as follows: characterization of pollutants from EGR processes; selective application of monitoring and measuring techniques; evaluation of control/mitigation techniques; and evaluation of the synergistic impacts of the development of EGR techniques. Environmental assessment activities scheduled by EDP include: assessment of ecological impacts; assessment of socioeconomic effects; EIA/EIS preparation; evaluation of control technology needs; andmore » analysis of applicable and proposed emission, effluent, and health and safety standards. The EGR EDP includes an EGR technology overview (Section 2), a discussion of EGR environmental issues and requirements (Section 3), an environmental action plan (Section 4), an environmental management strategy for the EGR program (Section 5), and supporting appendices which present information on Federal legislation applicable to EGR technology, a summary of ongoing and completed research, and future research and assessment projects.« less

Transconjunctival drainage of serous and hemorrhagic choroidal detachment.

PubMed

Rezende, Flávio A; Kickinger, Mônica C; Li, Gisèle; Prado, Renata F; Regis, Luiz Gustavo T

2012-02-01

To describe a novel surgical technique for drainage of bullous serous and hemorrhagic choroidal detachments. A prospective, consecutive case series of 6 eyes with serous and/or hemorrhagic choroidal detachments secondary to intraocular surgery was documented to evaluate the feasibility of using the 25-gauge and 20-gauge transconjunctival trocar/cannula systems to drain choroidal detachments. Two eyes had expulsive hemorrhagic choroidal detachments and 4 eyes had serous choroidal detachments after glaucoma surgeries. A 25-gauge infusion line was placed in the anterior chamber. A 20-gauge (in eyes with hemorrhagic choroidal detachments) or a 25-gauge (in eyes with serous detachments) trocar/cannula system was inserted into the suprachoroidal space 7.0 mm from limbus. After drainage, the cannulas were removed and no sutures were placed. Pars plana vitrectomy was performed only in eyes with concomitant pathology that demanded the additional procedure. The primary outcome measure was presence of choroidal detachment at 1 week, 2 weeks, and 1 month postoperatively. Secondary outcome measures were visual acuity at 6 months and intraocular pressure at 1 week and 1, 3, and 6 months postoperatively. Drainage of hemorrhagic choroidal detachments resulted in resolution of the detachments by 1 month postoperatively. In eyes with serous detachments, resolution was achieved by 1 week postdrainage. In both groups, intraocular pressure increased to at least 10 mmHg by postoperative Week 1. The visual acuity improved in all eyes. No complications related to the transconjunctival technique were noted. Transconjunctival drainage of serous and hemorrhagic choroidal detachments seems to be a feasible and simple surgical option with minimal scleral and conjunctival damage. Pars plana vitrectomy may not be necessary when draining choroidal detachments in this manner.

The effects of low impact development on urban flooding under different rainfall characteristics.

PubMed

Qin, Hua-peng; Li, Zhuo-xi; Fu, Guangtao

2013-11-15

Low impact development (LID) is generally regarded as a more sustainable solution for urban stormwater management than conventional urban drainage systems. However, its effects on urban flooding at a scale of urban drainage systems have not been fully understood particularly when different rainfall characteristics are considered. In this paper, using an urbanizing catchment in China as a case study, the effects of three LID techniques (swale, permeable pavement and green roof) on urban flooding are analyzed and compared with the conventional drainage system design. A range of storm events with different rainfall amounts, durations and locations of peak intensity are considered for holistic assessment of the LID techniques. The effects are measured by the total flood volume reduction during a storm event compared to the conventional drainage system design. The results obtained indicate that all three LID scenarios are more effective in flood reduction during heavier and shorter storm events. Their performance, however, varies significantly according to the location of peak intensity. That is, swales perform best during a storm event with an early peak, permeable pavements perform best with a middle peak, and green roofs perform best with a late peak, respectively. The trends of flood reduction can be explained using a newly proposed water balance method, i.e., by comparing the effective storage depth of the LID designs with the accumulative rainfall amounts at the beginning and end of flooding in the conventional drainage system. This paper provides an insight into the performance of LID designs under different rainfall characteristics, which is essential for effective urban flood management. Copyright © 2013 Elsevier Ltd. All rights reserved.

The role of external drains and peritoneal conduits in the treatment of recurrent chronic subdural hematoma.

PubMed

Santarius, Thomas; Qureshi, Hammad U; Sivakumaran, Ram; Kirkpatrick, Peter J; Kirollos, Ramez W; Hutchinson, Peter J

2010-06-01

A considerable body of evidence supporting the use of external drainage after evacuation of primary chronic subdural hematoma (CSDH) exists in the literature. However, no systematic study of the value of postoperative drainage in the treatment of recurrent CSDH has been published. The aim of the study was to investigate external drains and subdural-to-peritoneal conduit in the treatment of recurrent CSDH. A retrospective review of cases of CSDH treated in our institution between October 2002 and October 2006 was conducted. During the study period, 408 patients had burr hole evacuation. Sixty-four patients (15.9%) had treatment for recurrence. One patient had craniotomy, and the remaining 63 had another burr hole evacuation: 36 without placement of a drain (BHO), 14 with external drainage (SED), and 13 with placement of subdural-peritoneal catheter (SPC). Fifteen patients (24%) developed a secondary recurrence requiring a third drainage procedure. Postoperative drainage (SED or SPC) was associated with a significantly lower secondary recurrence rate when compared to BHO: 3/27 (11%) versus 12/36 (33%) (χ(2), P=.040). There was no significant difference in recurrence rates between SED and SPC. Postoperative complications included acute subdural hematoma (2), subdural empyema (2), brain edema (2), pneumonia (3), and in-hospital death (2). None of the complications was associated with the use of a specific technique. The results indicate that, as in the treatment of primary CSDHs, the use of drain (SED or SPC) with burr hole evacuation is safe and is associated with lower recurrence rate. Further investigation is needed to clarify the indications of currently available surgical techniques in the treatment of recurrent CSDH. Copyright © 2010 Elsevier Inc. All rights reserved.

Fluvial drainage networks: the fractal approach as an improvement of quantitative geomorphic analyses

NASA Astrophysics Data System (ADS)

Melelli, Laura; Liucci, Luisa; Vergari, Francesca; Ciccacci, Sirio; Del Monte, Maurizio

2014-05-01

Drainage basins are primary landscape units for geomorphological investigations. Both hillslopes and river drainage system are fundamental components in drainage basins analysis. As other geomorphological systems, also the drainage basins aim to an equilibrium condition where the sequence of erosion, transport and sedimentation approach to a condition of minimum energy effort. This state is revealed by a typical geometry of landforms and of drainage net. Several morphometric indexes can measure how much a drainage basin is far from the theoretical equilibrium configuration, revealing possible external disarray. In active tectonic areas, the drainage basins have a primary importance in order to highlight style, amount and rate of tectonic impulses, and morphometric indexes allow to estimate the tectonic activity classes of different sectors in a study area. Moreover, drainage rivers are characterized by a self-similarity structure; this promotes the use of fractals theory to investigate the system. In this study, fractals techniques are employed together with quantitative geomorphological analysis to study the Upper Tiber Valley (UTV), a tectonic intermontane basin located in northern Apennines (Umbria, central Italy). The area is the result of different tectonic phases. From Late Pliocene until present time the UTV is strongly controlled by a regional uplift and by an extensional phase with different sets of normal faults playing a fundamental role in basin morphology. Thirty-four basins are taken into account for the quantitative analysis, twenty on the left side of the basin, the others on the right side. Using fractals dimension of drainage networks, Horton's laws results, concavity and steepness indexes, and hypsometric curves, this study aims to obtain an evolutionary model of the UTV, where the uplift is compared to local subsidence induced by normal fault activity. The results highlight a well defined difference between western and eastern tributary basins, suggesting a greater disequilibrium in the last ones. The quantitative analysis points out the segments of the basin boundaries where the fault activity is more efficient and the resulting geomorphological implications.

Hydrological inferences through morphometric analysis of lower Kosi river basin of India for water resource management based on remote sensing data

NASA Astrophysics Data System (ADS)

Rai, Praveen Kumar; Chandel, Rajeev Singh; Mishra, Varun Narayan; Singh, Prafull

2018-03-01

Satellite based remote sensing technology has proven to be an effectual tool in analysis of drainage networks, study of surface morphological features and their correlation with groundwater management prospect at basin level. The present study highlights the effectiveness and advantage of remote sensing and GIS-based analysis for quantitative and qualitative assessment of flood plain region of lower Kosi river basin based on morphometric analysis. In this study, ASTER DEM is used to extract the vital hydrological parameters of lower Kosi river basin in ARC GIS software. Morphometric parameters, e.g., stream order, stream length, bifurcation ratio, drainage density, drainage frequency, drainage texture, form factor, circularity ratio, elongation ratio, etc., have been calculated for the Kosi basin and their hydrological inferences were discussed. Most of the morphometric parameters such as bifurcation ratio, drainage density, drainage frequency, drainage texture concluded that basin has good prospect for water management program for various purposes and also generated data base that can provide scientific information for site selection of water-harvesting structures and flood management activities in the basin. Land use land cover (LULC) of the basin were also prepared from Landsat data of 2005, 2010 and 2015 to assess the change in dynamic of the basin and these layers are very noteworthy for further watershed prioritization.

Endoscopic Transsphenoidal Cisternostomy for Nonneoplastic Sellar Cysts

PubMed Central

Su, Yukai; Ishii, Yudo; Lin, Chien-Min; Tahara, Shigeyuki; Teramoto, Akira; Morita, Akio

2015-01-01

Background and Importance. Sellar arachnoid cysts and Rathke's cleft cysts are benign lesions that produce similar symptoms, including optochiasmatic compression, pituitary dysfunction, and headache. Studies have reported the use of various surgical treatment methods for treating these symptoms, preventing recurrence, and minimizing operative complications. However, the postoperative cerebrospinal fluid (CSF) fistula and recurrence rate remain significant. Clinical Presentation. In this paper, we present 8 consecutive cases involving arachnoid cysts and Rathke's cleft cysts, which were managed by using drainage and cisternostomy, the intentional fenestration of the cyst into the subarachnoid space, and then meticulously closing sellar floor using dural sutures. The postoperative images, CSF fistula rate, and the recurrence rate were favorable. Conclusion. We report this technique and discuss the benefit of this minimally invasive approach. PMID:25685785

Can Vacuum Assisted Venous Drainage be Achieved using a Roller Pump in an Emergency? A Pilot Study using Neonatal Circuitry

PubMed Central

Hill, S. L.; Holt, D. W.

2007-01-01

Abstract: There has been much advancement in perfusion technology over its 50 years of progression. One of these techniques is vacuum-assisted venous drainage (VAVD). Many perfusionists augment venous drainage using VAVD, typically from a wall vacuum source. This study explores alternates to providing VAVD if the wall vacuum fails. In two porcine laboratories, ∼36 in. of 3/16-in. tubing was connected to a sucker return port and placed into the roller head next to the arterial pump. The vacuum was monitored with a DLP pressure monitoring system (Medtronic). This system was connected to small-bore tubing and attached to a stopcock on top of the reservoir. The vacuum was regulated using another stopcock connected to a non-filtered luer lock port on top of the reservoir or by a segment of 3 × 0.25-in.-diameter tubing attached to the vent port with a c-clamp. Vacuum drainage was achieved, ranging from −18 mmHg to −71 mmHg by manipulating the stopcock or c-clamp. Changes in venous drainage were seen by volume fluctuations in the venous reservoir. The vacuum was adjusted to account for dramatic changes. Augmented venous drainage using a roller pump can be achieved successfully during cardiopulmonary bypass (CPB). This method of active drainage can be used in lieu of wall suction or during times of emergency if wall suction fails. PMID:18293812

Measure Guideline: Guidance on Taped Insulating Sheathing Drainage Planes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Grin, A.; Lstiburek, J.

The goal of this research is to provide durable and long-term water management solutions using exterior insulating sheathing as part of the water management system. It is possible to tape or seal the joints in insulating sheathing to create a drainage plane and even an air control layer. There exists the material durability component of the tape as well as the system durability component being the taped insulating sheathing as the drainage plane. This measure guideline provides best practice and product recommendations from the interviewed contractors and homebuilders who collectively have a vast amount of experience. Three significant issues weremore » discussed with the group, which are required to make taped insulating sheathing a simple, long-term, and durable drainage plane: horizontal joints should be limited or eliminated wherever possible; where a horizontal joint exists use superior materials; and frequent installation inspection and regular trade training are required to maintain proper installation.« less

Landform Formation Under Ice Sheets

NASA Astrophysics Data System (ADS)

Schoof, C. G.; Ng, F. S.; Hallet, B.

2004-12-01

We present a new mathematical model for the formation of subglacial landforms such as drumlins under a warm-based, soft-bedded ice sheet. At the heart of the model is a channelized drainage system in which smaller channels grow at the expense of larger ones, leading to the continuous creation and extinction of drainage paths, and to a spatially distributed imprint on the landscape. We demonstrate how interactions between such a drainage system, bed topography and ice flow can lead to the spontaneous formation of subglacial landforms, and discuss the effect of different sediment transport characteristics in the drainage system on the shape and migration of these landforms. This mathematical model is the first component of a study of landscape/ice-sheet self-organization, which is inspired and guided, in part, by new digital topographic data (LIDAR) that are revealing with unprecedented detail the striking grain of glacially scoured topography on length scales ranging from 0.5 to 20 km.

Control of acid drainage from fresh coal refuse: food preservatives as economical alternatives to detergents

DOE Office of Scientific and Technical Information (OSTI.GOV)

Onysko, S.J.; Erickson, P.M.; Kleinmann, R.L.P.

Water soluble detergents such as sodium lauryl sulfate (SLS), which can sorb to pyritic materials, have been successfully used by the mining industry for acid drainage prevention in coal refuse. Detergent control of acid drainage from refuse may be uneconomical, however, at sites where extensive rainfall or groundwater movement results in rapid SLS washout. In this study, the performance of two alternative acid control chemicals, sodium benzoate and potassium sorbate, was compared with the performance of SLS in pilot-scale experiments with extensively leached, fresh coal refuse. Chemical cost information is presented that indicates low benzoate and sorbate doses were moremore » economical than comparable SLS doses under the experimental conditions of the study. The unique environmental compatibility of benzoate and sorbate, which are used in food and beverages in concentrations greater than those reported in this study for acid drainage suppression, is also discussed.« less

Water quality issues associated with agricultural drainage in semiarid regions

NASA Astrophysics Data System (ADS)

Sylvester, Marc A.

High incidences of mortality, birth defects, and reproductive failure in waterfowl using Kesterson Reservoir in the San Joaquin Valley, Calif., have occurred because of the bioaccumulation of selenium from irrigation drainage. These circumstances have prompted concern about the quality of agriculture drainage and its potential effects on human health, fish and wildlife, and beneficial uses of water. The U.S. Geological Survey (USGS) and Lawrence Berkeley Laboratory, University of California (Berkeley, Calif.) organized a 1-day session at the 1986 AGU Fall Meeting in San Francisco, Calif., to provide an interdisciplinary forum for hydrologists, geochemists, and aquatic chemists to discuss the processes controlling the distribution, mobilization, transport, and fate of trace elements in source rocks, soils, water, and biota in semiarid regions in which irrigated agriculture occurs. The focus of t h e session was the presentation of research results on the source, distribution, movement, and fate of selenium in agricultural drainage.

Endoscopic ultrasound comes of age: Mature, established, creative and here to stay!

PubMed Central

Bhutani, Manoop S.

2014-01-01

Research in endoscopic ultrasound (EUS) is alive and kicking! This paper will present recent interesting developments in EUS based on research presented at the Digestive Disease Week (DDW) held in Chicago in 2014. Endosonographers are looking at various techniques to improve yield of fine needle aspiration and core biopsies, assess circulating tumor cells, apply EUS for personalized medicine and develop devices to ensure the adequacy of sampling. EUS may open new vistas in understanding of neurogastroenterology and gastrointestinal motility disorders as discussed in this paper. EUS guided drainage of pancreatic fluid collections, bile duct and gallbladder is feasible, and many randomized trials are being done to compare different techniques. EUS guided delivery of fiducials, drugs, coils or chemo loaded beads in possible. EUS has come off age, has matured and is here to stay! The DDW in 2014 in Chicago was a very active year for EUS. There were numerous papers on different aspects of EUS, some perfecting and improving old techniques, others dealing with randomized trials and many with novel concepts. In this paper, I will highlight some of the papers that were presented. It is not possible to discuss all the abstracts in detail. I have, therefore, chosen selected papers in different aspects of EUS to give the readers a flavor of the kind of research that was presented at DDW. PMID:25184120

Occlusion of a Long-Term Transpleural Biliary Drainage Tract Using a Gelatin Pledget (Hep-Plug™).

PubMed

Kortes, Nikolas; Gnutzmann, Daniel; Konietzke, Philip; Mayer, Philipp; Sumkauskaite, Migle; Kauczor, Hans-Ulrich; Radeleff, Boris A

2017-11-01

This case describes a technique used to close a long-term 14F transpleural biliary drainage catheter tract to prevent biliopleural fistula and further complications. We deployed a compressed gelatin foam pledget provided in a pre-loaded delivery device (Hep-Plug™) along the intrahepatic tissue tract for sealing it against the pleural cavity. The device used is easy to handle and gives the Interventional Radiologist the possibility to safely manage and prevent complications after percutaneous transhepatic interventions.

Mine drainage control - design for reclamation and neutralization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Koehrsen, L.G.; Grandt, A.F.

1970-01-01

The Peabody Coal Company Mine Drainage Neutralization Plant at the Will Scarlet mine is a versatile, full-scale facility which should add much new dimension to the science of dealing with this troublesome waste in the next several years. Hopefully, this brief outline will give other persons concerned with the mine drainage neutralization a grasp of the scope of the Peabody Research Program. It is our plan to follow this background presentation in another year with discussion of the effectiveness of the research project and the results that have been achieved. The research project reported herein is supported in part bymore » Federal Water Pollution Control Administration Research and Development Grant 14010 DAX.« less

Greenhouse gas emissions from integrated urban drainage systems: Where do we stand?

NASA Astrophysics Data System (ADS)

Mannina, Giorgio; Butler, David; Benedetti, Lorenzo; Deletic, Ana; Fowdar, Harsha; Fu, Guangtao; Kleidorfer, Manfred; McCarthy, David; Steen Mikkelsen, Peter; Rauch, Wolfgang; Sweetapple, Chris; Vezzaro, Luca; Yuan, Zhiguo; Willems, Patrick

2018-04-01

As sources of greenhouse gas (GHG) emissions, integrated urban drainage systems (IUDSs) (i.e., sewer systems, wastewater treatment plants and receiving water bodies) contribute to climate change. This paper, produced by the International Working Group on Data and Models, which works under the IWA/IAHR Joint Committee on Urban Drainage, reviews the state-of-the-art and modelling tools developed recently to understand and manage GHG emissions from IUDS. Further, open problems and research gaps are discussed and a framework for handling GHG emissions from IUDSs is presented. The literature review reveals that there is a need to strengthen already available mathematical models for IUDS to take GHG into account.

Can Nocturnal Cold Air Drainage be Used to Monitor Ecosystem Function?

NASA Astrophysics Data System (ADS)

Pypker, T. G.; Unsworth, M. H.; Sulzman, E. W.; Lamb, B.; Allwine, G.; Mix, A. C.; Bond, B. J.

2005-12-01

Ecosystem carbon dynamics in flat, uniform terrain are commonly studied using standard micrometeorological techniques such as eddy covariance or gradient methods. But many of the world's ecosystems are in complex topography that is inappropriate for these methods. Nocturnal cold air drainage commonly occurs in mountainous terrain. This drainage provides an opportunity to monitor ecosystem carbon dynamics because as air flows downhill through a watershed, it collects respired CO2 from the soil and vegetation. If the nocturnal drainage can be treated as a river of air flowing down a valley, sampling this air from a tower at the base of a watershed could provide an estimate of ecosystem respiration and the 12C/13C ratio. To interpret the measured CO2 and the 12C/13C ratio, the characteristics of the drainage and the footprint (source area) of air passing the tower must be understood. To explore the potential of using nocturnal cold air drainage we built a 37 m tower at the base of a deeply incised watershed of ~40 y-old Douglas-fir in the Oregon Cascades. At various heights on the tower we monitored air temperature, wind speed/direction, and the CO2 concentration and 12C/13C isotopic ratio with a combination of thermistors, sonic anemometers (2-D and 3-D) and a CO2 profile system. The temperature gradient along the axis of the watershed was monitored by 30 temperature sensors from the base to the top of the watershed. The maximum drainage windspeeds on the tower occurred near sunset and, unlike past reports of cold air drainage, this drainage was very deep (> 37 m). The drainage became well mixed when the vertical profile of potential temperature became isothermal. It remained well mixed through the night into the early morning. The drainage occurred on most summer nights and typically provided a range of CO2 (> 60 ppm) sufficient for "Keeling plot" analysis. In September 2005, we released a tracer in the watershed (SF6) to determine the varying footprint size of the tower. The footprint size and windspeed varied throughout the night, resulting in a change in the CO2 concentration at the tower. Further analysis will determine how the CO2 passing the tower is altered by entrainment of the air overlying the drainage and the change in the source area of the drainage.

Methods for estimating selected flow-duration and flood-frequency characteristics at ungaged sites in Central Idaho

USGS Publications Warehouse

Kjelstrom, L.C.

1998-01-01

Methods for estimating daily mean discharges for selected flow durations and flood discharge for selected recurrence intervals at ungaged sites in central Idaho were applied using data collected at streamflow-gaging stations in the area. The areal and seasonal variability of discharge from ungaged drainage basins may be described by estimating daily mean discharges that are exceeded 20, 50, and 80 percent of the time each month. At 73 gaging stations, mean monthly discharge was regressed with discharge at three points—20, 50, and 80—from daily mean flow-duration curves for each month. Regression results were improved by dividing the study area into six regions. Previously determined estimates of mean monthly discharge from about 1,200 ungaged drainage basins provided the basis for applying the developed techniques to the ungaged basins. Estimates of daily mean discharges that are exceeded 20, 50, and 80 percent of the time each month at ungaged drainage basins can be made by multiplying mean monthly discharges estimated at ungaged sites by a regression factor for the appropriate region. In general, the flow-duration data were less accurately estimated at discharges exceeded 80 percent of the time than at discharges exceeded 20 percent of the time. Curves drawn through the three points for each of the six regions were most similar in July and most different from December through March. Coefficients of determination of the regressions indicate that differences in mean monthly discharge largely explain differences in discharge at points on the daily mean flow-duration curve. Inherent in the method are errors in the technique used to estimate mean monthly discharge. Flood discharge estimates for selected recurrence intervals at ungaged sites upstream or downstream from gaging stations can be determined by a transfer technique. A weighted ratio of drainage area times flood discharge for selected recurrence intervals at the gaging station can be used to estimate flood discharge at the ungaged site. Best results likely are obtained when the difference between gaged and ungaged drainage areas is small.

Recovery from anterograde and retrograde amnesia after percutaneous drainage of a cystic craniopharyngioma.

PubMed Central

Ignelzi, R J; Squire, L R

1976-01-01

A case is reported of a cystic craniopharyngioma involving the floor and walls of the third ventricle. Pronounced anterograde and retrograde amnesia were documented preoperatively by formal testing. Rapid improvement in both new learning capacity and remote memory occurred after percutaneous twist drill drainage of the cystic portion of the tumour. The relevance of these observations to the amnesic syndrome and its neuropathological basis is discussed. Images PMID:1011035

Transbronchial Catheter Drainage via Fiberoptic Bronchoscope in Intractable Lung Abscess

PubMed Central

Jeong, Man Pyo; Kim, Woo Sung; Han, Sung Koo; Shim, Young Soo; Kim, Keun Youl; Han, Yong Chol

1989-01-01

The use of the fiberoptic bronchoscope as a drainage procedure for lung abscess has become more and more widespread. We have recently adopted the technique of inserting a simple polyethylene catheter through the flexible fiberoptic bronchoscope into the abscess cavity of 11 patients with lung absess. All cases had not responded to aggressive postural drainage and adequate antibiotic therapy for at least a week. The results were as follows: Among 11 patients, the therapeutic response was dramatic in 6 patients.In the successful group, the abscess sizes were greater than 8cm in diameter and the air-fluid levels were higher than two-thirds of the cavity.Additional diagnoses, other than bacterial lung abscess, could be made in 2 cases when otherwise the diagnosis would have remained in doubt. The authors suggest that catheter drainage via fiberoptic bronchoscpope is an effective treatment modality in the large lung abscess with a high air-fluid level which is intractable to other medical approaches, and it is also a safe procedure. PMID:2487405

Dengue transmission based on urban environmental gradients in different cities of Pakistan.

PubMed

Khalid, Bushra; Ghaffar, Abdul

2015-03-01

This study focuses on the dengue transmission in different regions of Pakistan. For this purpose, the data of dengue cases for 2009-2012 from four different cities (Rawalpindi, Islamabad, Lahore, and Karachi) of the country is collected, evaluated, and compiled. To identify the reasons and regions of higher risk of Dengue transmission, land use classification, analysis of climate covariates and drainage patterns was done. Analysis involves processing of SPOT 5 10 m, Landsat TM 30 m data sets, and SRTM 90 m digital elevation models by using remote sensing and GIS techniques. The results are based on the change in urbanization and population density, analysis of temperature, rainfall, and wind speed; calculation of drainage patterns including stream features, flow accumulation, and drainage density of the study areas. Results suggest that the low elevation areas with calm winds and minimum temperatures higher than the normal, rapid increase in unplanned urbanization, low flow accumulation, and higher drainage density areas favor the dengue transmission.

Technique for estimating the 2- to 500-year flood discharges on unregulated streams in rural Missouri

USGS Publications Warehouse

Alexander, Terry W.; Wilson, Gary L.

1995-01-01

A generalized least-squares regression technique was used to relate the 2- to 500-year flood discharges from 278 selected streamflow-gaging stations to statistically significant basin characteristics. The regression relations (estimating equations) were defined for three hydrologic regions (I, II, and III) in rural Missouri. Ordinary least-squares regression analyses indicate that drainage area (Regions I, II, and III) and main-channel slope (Regions I and II) are the only basin characteristics needed for computing the 2- to 500-year design-flood discharges at gaged or ungaged stream locations. The resulting generalized least-squares regression equations provide a technique for estimating the 2-, 5-, 10-, 25-, 50-, 100-, and 500-year flood discharges on unregulated streams in rural Missouri. The regression equations for Regions I and II were developed from stream-flow-gaging stations with drainage areas ranging from 0.13 to 11,500 square miles and 0.13 to 14,000 square miles, and main-channel slopes ranging from 1.35 to 150 feet per mile and 1.20 to 279 feet per mile. The regression equations for Region III were developed from streamflow-gaging stations with drainage areas ranging from 0.48 to 1,040 square miles. Standard errors of estimate for the generalized least-squares regression equations in Regions I, II, and m ranged from 30 to 49 percent.

Esophageal cancer: anatomic particularities, staging, and imaging techniques.

PubMed

Encinas de la Iglesia, J; Corral de la Calle, M A; Fernández Pérez, G C; Ruano Pérez, R; Álvarez Delgado, A

2016-01-01

Cancer of the esophagus is a tumor with aggressive behavior that is usually diagnosed in advanced stages. The absence of serosa allows it to spread quickly to neighboring mediastinal structures, and an extensive lymphatic drainage network facilitates tumor spread even in early stages. The current TNM classification, harmonized with the classification for gastric cancer, provides new definitions for the anatomic classification, adds non-anatomic characteristics of the tumor, and includes tumors of the gastroesophageal junction. Combining endoscopic ultrasound, computed tomography, positron emission tomography, and magnetic resonance imaging provides greater accuracy in determining the initial clinical stage, and these imaging techniques play an essential role in the selection, planning, and evaluation of treatment. In this article, we review some particularities that explain the behavior of this tumor and we describe the current TNM staging system; furthermore, we discuss the different imaging tests available for its evaluation and include a diagnostic algorithm. Copyright © 2016 SERAM. Publicado por Elsevier España, S.L.U. All rights reserved.

Cranial dural arteriovenous shunts. Part 4. Clinical presentation of the shunts with leptomeningeal venous drainage.

PubMed

Baltsavias, Gerasimos; Spiessberger, Alex; Hothorn, Torsten; Valavanis, Anton

2015-04-01

Cranial dural arteriovenous fistulae have been classified into high- and low-risk lesions mainly based on the pattern of venous drainage. Those with leptomeningeal venous drainage carry a higher risk of an aggressive clinical presentation. Recently, it has been proposed that the clinical presentation should be considered as an additional independent factor determining the clinical course of these lesions. However, dural shunts with leptomeningeal venous drainage include a very wide spectrum of inhomogeneous lesions. In the current study, we correlated the clinical presentation of 107 consecutive patients harboring cranial dural arteriovenous shunts with leptomeningeal venous drainage, with their distinct anatomic and angiographic features categorized into eight groups based on the "DES" (Directness and Exclusivity of leptomeningeal venous drainage and features of venous Strain) concept. We found that among these groups, there are significant angioarchitectural differences, which are reflected by considerable differences in clinical presentation. Leptomeningeal venous drainage of dural sinus shunts that is neither direct nor exclusive and without venous strain manifested only benign symptoms (aggressive presentation 0%). On the other end of the spectrum, the bridging vein shunts with direct and exclusive leptomeningeal venous drainage and venous strain are expected to present aggressive symptoms almost always and most likely with bleeding (aggressive presentation 91.5%). Important aspects of the above correlations are discussed. Therefore, the consideration of leptomeningeal venous drainage alone, for prediction of the clinical presentation of these shunts appears insufficient. Angiographic analysis based on the above concept, offers the possibility to distinguish the higher- from the lower-risk types of leptomeningeal venous drainage. In this context, consideration of the clinical presentation as an additional independent factor for the prediction of their clinical course seems superfluous and possibly misleading. Topography is connected to the clinical presentation of the dural shunts inasmuch as the former determines the venous anatomy and the angioarchitectural features of the lesions.

Preserving the distribution of inorganic arsenic species in groundwater and acid mine drainage samples

USGS Publications Warehouse

Bednar, A.J.; Garbarino, J.R.; Ranville, J.F.; Wildeman, T.R.

2002-01-01

The distribution of inorganic arsenic species must be preserved in the field to eliminate changes caused by metal oxyhydroxide precipitation, photochemical oxidation, and redox reactions. Arsenic species sorb to iron and manganese oxyhydroxide precipitates, and arsenite can be oxidized to arsenate by photolytically produced free radicals in many sample matrices. Several preservatives were evaluated to minimize metal oxyhydroxide precipitation, such as inorganic acids and ethylenediaminetetraacetic acid (EDTA). EDTA was found to work best for all sample matrices tested. Storing samples in opaque polyethylene bottles eliminated the effects of photochemical reactions. The preservation technique was tested on 71 groundwater and six acid mine drainage samples. Concentrations in groundwater samples reached 720 ??g-As/L for arsenite and 1080 ??g-As/L for arsenate, and acid mine drainage samples reached 13 000 ??g-As/L for arsenite and 3700 ??g-As/L for arsenate. The arsenic species distribution in the samples ranged from 0 to 90% arsenite. The stability of the preservation technique was established by comparing laboratory arsenic speciation results for samples preserved in the field to results for subsamples speciated onsite. Statistical analyses indicated that the difference between arsenite and arsenate concentrations for samples preserved with EDTA in opaque bottles and field speciation results were analytically insignificant. The percentage change in arsenite:arsenate ratios for a preserved acid mine drainage sample and groundwater sample during a 3-month period was -5 and +3%, respectively.

Augmented reality in the surgery of cerebral arteriovenous malformations: technique assessment and considerations.

PubMed

Cabrilo, Ivan; Bijlenga, Philippe; Schaller, Karl

2014-09-01

Augmented reality technology has been used for intraoperative image guidance through the overlay of virtual images, from preoperative imaging studies, onto the real-world surgical field. Although setups based on augmented reality have been used for various neurosurgical pathologies, very few cases have been reported for the surgery of arteriovenous malformations (AVM). We present our experience with AVM surgery using a system designed for image injection of virtual images into the operating microscope's eyepiece, and discuss why augmented reality may be less appealing in this form of surgery. N = 5 patients underwent AVM resection assisted by augmented reality. Virtual three-dimensional models of patients' heads, skulls, AVM nidi, and feeder and drainage vessels were selectively segmented and injected into the microscope's eyepiece for intraoperative image guidance, and their usefulness was assessed in each case. Although the setup helped in performing tailored craniotomies, in guiding dissection and in localizing drainage veins, it did not provide the surgeon with useful information concerning feeder arteries, due to the complexity of AVM angioarchitecture. The difficulty in intraoperatively conveying useful information on feeder vessels may make augmented reality a less engaging tool in this form of surgery, and might explain its underrepresentation in the literature. Integrating an AVM's hemodynamic characteristics into the augmented rendering could make it more suited to AVM surgery.

Placement of percutaneous transhepatic biliary stent using a silicone drain with channels

PubMed Central

Yoshida, Hiroshi; Mamada, Yasuhiro; Taniai, Nobuhiko; Mineta, Sho; Mizuguchi, Yoshiaki; Kawano, Yoichi; Sasaki, Junpei; Nakamura, Yoshiharu; Aimoto, Takayuki; Tajiri, Takashi

2009-01-01

This report describes a method for percutaneous transhepatic biliary stenting with a BLAKE Silicone Drain, and discusses the usefulness of placement of the drain connected to a J-VAC Suction Reservoir for the treatment of stenotic hepaticojejunostomy. Percutaneous transhepatic biliary drainage was performed under ultrasonographic guidance in a patient with stenotic hepaticojejunostomy after hepatectomy for hepatic hilum malignancy. The technique used was as follows. After dilatation of the drainage root, an 11-Fr tube with several side holes was passed through the stenosis of the hepaticojejunostomy. A 10-Fr BLAKE Silicone Drain is flexible, which precludes one-step insertion. One week after insertion of the 11-Fr tube, a 0.035-inch guidewire was inserted into the tube. After removal of the 11-Fr tube, the guidewire was put into the channel of a 10-Fr BLAKE Silicone Drain. The drain was inserted into the jejunal limb through the intrahepatic bile duct and was connected to a J-VAC Suction Reservoir. Low-pressure continued suction was applied. Patients can be discharged after insertion of the 10-Fr BLAKE Silicone Drain connected to the J-VAC Suction Reservoir. Placement of a percutaneous transhepatic biliary stent using a 10-Fr BLAKE Silicone Drain connected to a J-VAC Suction Reservoir is useful for the treatment of stenotic hepaticojejunostomy. PMID:19725159

Transanal drainage tube reduces rate and severity of anastomotic leakage in patients with colorectal anastomosis: A case controlled study.

PubMed

Brandl, A; Czipin, S; Mittermair, R; Weiss, S; Pratschke, J; Kafka-Ritsch, R

2016-03-01

The aim of this study was to investigate the clinical usefulness of the placement of a transanal drainage tube to prevent anastomotic leakage in colorectal anastomoses. This single-center retrospective trial included all patients treated with surgery for benign or malign colorectal disease between January 2009 and December 2012. The transanal drainage tube was immediately placed after colorectal anastomosis until day five and was routinely used since 2010. Patients treated with a transanal drainage tube were compared with the control group. Statistical analysis was performed using Fisher's exact or Chi-square tests for group comparison and a linear regression model for multivariate analysis. This study included 242 patients (46% female; median age 63 years; range 18-93); 34% of the patients underwent a laparoscopic procedure, and 57% of the patients received a placement of a transanal drainage tube. Anastomotic leakage occurred in 19 patients (7.9%). Univariate analysis showed a higher rate of anastomotic leakage in patients with an ASA score 4 (p = 0.02) and a lower rate in patients with transanal drainage placement (3.6% vs. 13.6%; p = 0.007). The grading of the complication of anastomotic leakage was reduced with transanal drainage (e.g., Dindo ≧ 3b: 20.0% vs. 92.9%; p = 0.006), and the hospital stay was shortened (17.6 ± 12.5 vs. 22.1 ± 17.6 days; p = 0.02). Multivariate analysis revealed that transanal drainage was the only significant factor (HR = -2.90; -0.168 to -0.032; p = 0.007) affecting anastomotic leakage. Placement of a transanal drainage tube in patients with colorectal anastomoses is a safe and simple technique to perform and reduces anastomotic leakage, the severity of the complication and hospital stay.

A new model for simulating spring discharge recession and estimating effective porosity of karst aquifers

NASA Astrophysics Data System (ADS)

Xu, Bin; Ye, Ming; Dong, Shuning; Dai, Zhenxue; Pei, Yongzhen

2018-07-01

Quantitative analysis of recession curves of karst spring hydrographs is a vital tool for understanding karst hydrology and inferring hydraulic properties of karst aquifers. This paper presents a new model for simulating karst spring recession curves. The new model has the following characteristics: (1) the model considers two separate but hydraulically connected reservoirs: matrix reservoir and conduit reservoir; (2) the model separates karst spring hydrograph recession into three stages: conduit-drainage stage, mixed-drainage stage (with both conduit drainage and matrix drainage), and matrix-drainage stage; and (3) in the mixed-drainage stage, the model uses multiple conduit layers to present different levels of conduit development. The new model outperforms the classical Mangin model and the recently developed Fiorillo model for simulating observed discharge at the Madison Blue Spring located in northern Florida. This is attributed to the latter two characteristics of the new model. Based on the new model, a method is developed for estimating effective porosity of the matrix and conduit reservoirs for the three drainage stages. The estimated porosity values are consistent with measured matrix porosity at the study site and with estimated conduit porosity reported in literature. The new model for simulating karst spring hydrograph recession is mathematically general, and can be applied to a wide range of karst spring hydrographs to understand groundwater flow in karst aquifers. The limitations of the model are discussed at the end of this paper.

Endoscopic Evacuation of Subdural Collections.

PubMed

Boyaci, Suat; Gumustas, Oguzhan Guven; Korkmaz, Serdar; Aksoy, Kaya

2016-01-01

Intraoperative use of the endoscope is a hot topic in neurosurgery and it gives broader visualization of critical and hardlyreached areas. Endoscope-assisted surgical approach to chronic subdural haematoma (SDH) is a minimally invasive technique and may give an expansion to the regular method of burr-hole haematoma drainage. Endoscope-assisted haematoma drainage with mini-craniotomy was performed over a 24-month period, and prospectively collected data is reviewed. A total of 10 procedures (8 patients) were performed using the endoscopeassisted technique. Four of them were chronic SDH and six were subacute SDH. Procedures were extended 20 minutes in average because of endoscopic intervention. There was no extra-morbidity through the study as a consequence of endoscopic assessment. Endoscope-assisted techniques can make the operation safe in selected circumstances with improved intraoperative visualization. It may likewise take into consideration the identification and destruction of neo-membranes, septums and solid clots. In addition, the source of bleeding can be easily coagulated. The endoscope-assisted techniques, with all of these features, can alter the pre- and intra-operative decision-making for selected patients.

Combined Scleral Flap with Donor Scleral Patch Graft for Anterior Tube Placement in Glaucoma Drainage Device Surgery.

PubMed

Yu, Jea H; Nguyen, Chuck; Gallemore, Esmeralda; Gallemore, Ron P

2016-01-01

Purpose . To report a new technique for anterior placement of tubes for glaucoma drainage devices to reduce the risk of tube erosions. Methods . Retrospective review of select cases of Ahmed Valve surgery combined with the novel method of a limbal-based scleral flap covered by a scleral patch graft to cover the tube at the entrance through the limbus. Intraoperative and postoperative illustrations are shown to highlight the method of tube placement. Results . In this retrospective case series, 3 patients are presented illustrating the technique. Two had neovascular glaucoma and one had primary open-angle glaucoma (POAG). On average, intraocular pressure was reduced from 39 ± 14 mmHg to 15 ± 2 mmHg and the number of glaucoma medications was reduced from 4 ± 1 to 0. Preoperative and most recent visual acuities were hand-motion (HM) and HM, 20/60 and 20/50, and 20/70 and 20/30, respectively. Conclusion . The combination of a limbal-based scleral flap with scleral patch graft to cover the tube with glaucoma drainage devices may be an effective means to reduce erosion and protect against endophthalmitis.

Application of remote-sensing techniques to hydrologic studies in selected coal-mine areas of southeastern Kansas

USGS Publications Warehouse

Kenny, J.F.; McCauley, J.R.

1983-01-01

Disturbances resulting from intensive coal mining in the Cherry Creek basin of southeastern Kansas were investigated using color and color-infrared aerial photography in conjunction with water-quality data from simultaneously acquired samples. Imagery was used to identify the type and extent of vegetative cover on strip-mined lands and the extent and success of reclamation practices. Drainage patterns, point sources of acid mine drainage, and recharge areas for underground mines were located for onsite inspection. Comparison of these interpretations with water-quality data illustrated differences between the eastern and western parts of the Cherry Creek basin. Contamination in the eastern part is due largely to circulation of water from unreclaimed strip mines and collapse features through the network of underground mines and subsequent discharge of acidic drainage through seeps. Contamination in the western part is primarily caused by runoff and seepage from strip-mined lands in which surfaces have frequently been graded and limed but are generally devoid of mature stands of soil-anchoring vegetation. The successful use of aerial photography in the study of Cherry Creek basin indicates the potential of using remote-sensing techniques in studies of other coal-mined regions. (USGS)

Watershed models for instructional films

Treesearch

Peter E. Black; Raymond E. Leonard

1970-01-01

Watershed models, with a special sponge material that simulates soil drainage, were used to make an instructional film on subsurface flow and stream flow. Construction of the models and filming techniques are described.

Suprachoroidal drainage with collagen sheet implant- a novel technique for non-penetrating glaucoma surgery.

PubMed

Szurman, Peter; Januschowski, Kai; Boden, Karl Thomas; Seuthe, Anna-Maria

2018-02-01

Our purpose was both to introduce the new technique of suprachoroidal drainage with collagen sheet implantation as a novel technique of non-penetrating glaucoma surgery and to present first results of a prospective pilot study. A superficial rectangular sclera flap of half-scleral thickness sized 4 × 4.5 mm is dissected anteriorly until clear cornea. Then, a second scleral flap is created underneath the first one sized 3.5x4mm and is cut down full-thickness to the choroid exposing the suprachoroidal space. The flap is then bluntly prepared until the scleral spur is reached. Sharp dissection above the sclera spur exposes Schlemm's canal, which is located directly anteriorly. Schlemm's canal is unroofed, juxtacanalicular meshwork is peeled and the deep flap is cut off at its base. An absorbable collagen sheet (Ologen®, Dahlhausen, Cologne, Germany) is placed into the suprachoroidal space at the level of the ciliary body, and the superficial sclera flap is sutured tightly to prevent leakage. We prospectively analyzed 65 eyes that underwent suprachoroidal drainage with collagen sheet implantation. Mean reduction of intraocular pressure after 3 months was 35.1% (from 21.0 ± 4.3 mmHg to 13.5 ± 3.4 mmHg)(p < 0.01) and after 12 months 35.6% (from 21.0 ± 4.3 mmHg to 13.5 ± 3.0  mmHg)(p < 0.01). The number of topical IOP-reducing medication decreased significantly from 3.5 ± 0.7 to 0.6 ± 0.9 and to 0.9 ± 1.1 after 3 and 12 months, respectively (p < 0.01). No serious complications occurred. Suprachoroidal drainage with collagen sheet implantation seems to be a safe and effective surgical technique for non-penetrating glaucoma surgery that yields the opportunity of a sufficient IOP reduction for eyes unsuitable for canaloplasty.

Re-engineering the urban drainage system for resource recovery and protection of drinking water supplies.

PubMed

Gumbo, B

2000-01-01

The Harare metropolis in Zimbabwe, extending upstream from Manyame Dam in the Upper Manyame River Basin, consists of the City of Harare and its satellite towns: Chitungwiza, Norton, Epworth and Ruwa. The existing urban drainage system is typically a single-use-mixing system: water is used and discharged to "waste", excreta are flushed to sewers and eventually, after "treatment", the effluent is discharged to a drinking water supply source. Polluted urban storm water is evacuated as fast as possible. This system not only ignores the substantial value in "waste" materials, but it also exports problems to downstream communities and to vulnerable fresh-water sources. The question is how can the harare metropolis urban drainage system, which is complex and has evolved over time, be rearranged to achieve sustainability (i.e. water conservation, pollution prevention at source, protection of the vulnerable drinking water sources and recovery of valuable materials)? This paper reviews current concepts regarding the future development of the urban drainage system in line with the new vision of "Sustainable Cities of the Future". The Harare Metropolis in Zimbabwe is taken as a case, and philosophical options for re-engineering the drainage system are discussed.

Ground-water problems in highway construction and maintenance

USGS Publications Warehouse

Rasmussen, W.C.; Haigler, L.B.

1953-01-01

This report discusses the occurrence of ground water in relation to certain problems in highway construction and maintenance. These problems are: the subdrainage of roads; quicksand; the arrest of soil creep in road cuts; the construction of lower and larger culverts necessitated by the farm-drainage program; the prevention of failure of bridge abutments and retaining walls; and the water-cement ratio of sub-water-table concrete. Although the highway problems and suggested solutions are of general interest, they are considered with special reference to the State of Delaware, in relation to the geology of that State. The new technique of soil stabilization by electroosmosis is reviewed in the hope that it might find application here in road work and pile setting, field application by the Germans and Russians is reviewed.

Endoscopic and Photodynamic Therapy of Cholangiocarcinoma

PubMed Central

Meier, Benjamin; Caca, Karel

2016-01-01

Background Most patients with cholangiocarcinoma (CCA) have unresectable disease. Endoscopic bile duct drainage is one of the major objectives of palliation of obstructive jaundice. Methods/Results Stent implantation using endoscopic retrograde cholangiography is considered to be the standard technique. Unilateral versus bilateral stenting is associated with different advantages and disadvantages; however, a standard approach is still not defined. As there are various kinds of stents, there is an ongoing discussion on which stent to use in which situation. Palliation of obstructive jaundice can be augmented through the use of photodynamic therapy (PDT). Studies have shown a prolonged survival for the combinations of PDT and different stent applications as well as combinations of PDT and additional systemic chemotherapy. Conclusion More well-designed studies are needed to better evaluate and standardize endoscopic treatment of unresectable CCA. PMID:28229075

Endoscopic and Photodynamic Therapy of Cholangiocarcinoma.

PubMed

Meier, Benjamin; Caca, Karel

2016-12-01

Most patients with cholangiocarcinoma (CCA) have unresectable disease. Endoscopic bile duct drainage is one of the major objectives of palliation of obstructive jaundice. Stent implantation using endoscopic retrograde cholangiography is considered to be the standard technique. Unilateral versus bilateral stenting is associated with different advantages and disadvantages; however, a standard approach is still not defined. As there are various kinds of stents, there is an ongoing discussion on which stent to use in which situation. Palliation of obstructive jaundice can be augmented through the use of photodynamic therapy (PDT). Studies have shown a prolonged survival for the combinations of PDT and different stent applications as well as combinations of PDT and additional systemic chemotherapy. More well-designed studies are needed to better evaluate and standardize endoscopic treatment of unresectable CCA.

The dangers of long-term catheter drainage.

PubMed

Lowthian, P

There are many dangers associated with long-term urinary bladder drainage by catheter. For various reasons, the choice of catheter is important, and its initial insertion can be particularly hazardous. All catheterizations should, however, be safer when there is some urine (or other fluid) in the bladder. The appropriate choice of drainage system attached to the catheter can delay bacterial invasion of the bladder. Great care is needed to prevent blockage of the system, particularly when bacteriuria is present. Recent evidence indicates that some bacteria encourage the development of encrustations, so that, in some circumstances, catheters may become blocked within 24 hours. This, together with other considerations, strongly suggests that indwelling catheters should be changed at intervals of not more than 5 days. The practical implications of this are considered, as are the benefits that may accrue. Accidental catheter traction is another danger, and some possible methods of avoiding this are discussed. Finally, the need for a new kind of drainage-bag support is highlighted.

Paediatric empyema: a case report and literature review.

PubMed

Parsons, S J; Fenton, E; Williams, M

2005-06-01

To present a case of bilateral parapneumonic effusions in a child with Pneumococcal pneumonia and bacteraemia managed aggressively with early thoracotomies. The literature from peer reviewed journals is summarized and the different management strategies are discussed. Articles and reviews from peer reviewed journals on the management of empyema in children and adults. Staging of parapneumonic pleural effusions is difficult to assess clinically and radiologically. Most cases can be successfully managed with simple chest tube drainage, plus appropriate antibiotic therapy. However, based on the available evidence for children, thoracotomy with decortication and direct drainage may provide the most effective treatment in terms of length of hospital stay and duration of chest tube insertion, when compared with video assisted thoracoscopic surgery (VATS) or chest tube drainage, with or without intrapleural fibrinolytic therapy. More conservative approaches to treatment of empyema may be appropriate initially to avoid the cosmetic and other disadvantages of thoracotomy. However, delayed surgical drainage increases morbidity and may potentially increase mortality.

Environmental Impact Statement For the Disposal and Reuse of Hunters Point Shipyard Volume 2: Response to Comments

DTIC Science & Technology

2000-03-01

discussed. There are two requirements of the permit designed to meet the goals of the program: 1) design and implementation of BMPs to control runoff...affect these species. NMFS is aware that specific upgrades to the sanitary sewer and storm drainage systems have yet to be designed and the proposed...Specific 8 upgrades to the sanitary sewer and storm drainage systems, though not yet designed , 9 will meet both City and County of San Francisco and

Identification of the Lymphatic Drainage Pattern of Esophageal Cancer with Near-Infrared Fluorescent Imaging.

PubMed

Schlottmann, Francisco; Barbetta, Arianna; Mungo, Benedetto; Lidor, Anne O; Molena, Daniela

2017-03-01

Nodal status is one of the most important long-term prognostic factors for esophageal cancer. The aim of this study was to evaluate the ability of near-infrared (NIR) light fluorescent imaging to identify the lymphatic drainage pattern of esophageal cancer. Patients with distal esophageal cancer or esophagogastric junction cancer scheduled for esophagectomy were enrolled in this study. Before surgery, an endoscopy was performed with submucosal injection of 2 cc of indocyanine green (ICG) around the tumor. Real-time NIR images from the surgical field were obtained for each patient to visualize the lymphatic ICG drainage. A total of nine patients were included in this study. Ivor Lewis esophagectomy was performed in all cases. ICG drainage was visualized to first drain along the left gastric nodes in eight patients (88.9%) and toward the diaphragmatic nodes in one patient (11.1%). The median number of resected nodes was 32. Three patients (33.3%) presented nodal involvement. All of them had positive nodes in the first nodal station identified with ICG. Evaluation of the lymphatic drainage pattern with real-time NIR light fluorescent technique is feasible. Distal and esophagogastric junction tumors showed to drain first in the left gastric nodes in most of the cases.

Scaling relationships of channel networks at large scales: Examples from two large-magnitude watersheds in Brittany, France

NASA Astrophysics Data System (ADS)

Crave, A.; Davy, P.

1997-01-01

We present a statistical analysis on two watersheds in French Brittany whose drainage areas are about 10,000 and 2000 km2. The channel system was analysed from the digitised blue lines of the 1:100,000 map and from a 250-m DEM. Link lengths follow an exponential distribution, consistent with the Markovian model of channel branching proposed by Smart (1968). The departure from the exponential distribution for small lengths, that has been extensively discussed before, results from a statistical effect due to the finite number of channels and junctions. The Strahler topology applied on channels defines a self-similar organisation whose similarity dimension is about 1.7, that is clearly smaller than the value of 2 expected for a random organisation. The similarity dimension is consistent with an independent measurement of the Horton ratios of stream numbers and lengths. The variables defined by an upstream integral (drainage area, mainstream length, upstream length) follow power-law distributions limited at large scales by a finite size effect, due to the finite area of the watersheds. A special emphasis is given to the exponent of the drainage area, aA, that has been previously discussed in the context of different aggregation models relevant to channel network growth. We show that aA is consistent with 4/3, a value that was obtained and analytically demonstrated from directed random walk aggregating models, inspired by the model of Scheidegger (1967). The drainage density and mainstream length present no simple scaling with area, except at large areas where they tend to trivial values: constant density and square root of drainage area, respectively. These asymptotic limits necessarily imply that the space dimension of channel networks is 2, equal to the embedding space. The limits are reached for drainage areas larger than 100 km2. For smaller areas, the asymptotic limit represents either a lower bound (drainage density) or an upper bound (mainstream length) of the distributions. Because the fluctuations of the drainage density slowly converge to a finite limit, the system could be adequately described as a fat fractal, where the average drainage density is the sum of a constant plus a fluctuation decreasing as a power law with integrating area. A fat fractal hypothesis could explain why the similarity dimension is not equal to the fractal capacity dimension, as it is for thin fractals. The physical consequences are not yet really understood, but we draw an analogy with a directed aggregating system where the growth process involves both stochastic and deterministic growth. These models are known to be fat fractals, and the deterministic growth, which constitutes a fundamental ingredient of these models, could be attributed in river systems to the role of terrestrial gravity.

[Anesthetic infiltration of the spermatic cord in surgery for voluminous hydrocele].

PubMed

Reale, C; Corinti, R; Galullo, B; Borgonuovo, P; Borgonuovo, P

1998-06-01

The use of a new technique in spermatic cord block in surgical treatment of large hydroceles is reported. Identification of the cord in these cases is often difficult due to the presence of the hydrocele. The reported technique consists in the percutaneous drainage of the hydrocele prior to the block, in order to allow an easier identification of the cord. The block is then performed by the usual method. 108 patients with large hydroceles (above 250 mls) underwent surgical repair employing this approach. In only one case the cord was not identified even after drainage due to the effects of a previous hernioplasty. In the remaining 107 patients the cord was easily identified and blocked. The excellent results obtained with this approach, show that cord block is possible in all patients, even when a large hydrocele is present.

[Preliminary experience on endoscopic endonasal management of petrous apex cholesterol granuloma].

PubMed

Wang, Jin; Chen, Lei; Yang, Jing

2015-05-01

To explore the feasibility and related aspects on endoscopic endonasal management of petrous apex cholesterol granuloma. Retrospective data analysis was performed on 3 cases in which the endoscopic endonasal approach was used to manage this lesion between 2011 and 2014. Case information including radiological data, surgical technique, symptoms, and complications was reviewed. The main clinical manifestations in these 3 patients were tinnitus, hearing loss at the hearing threshold of 40-50 dBHL. After operation, all 3 patients showed disappearance of their tinnitus and improvement of the hearing threshold of 10-30 dBHL (follow-up 6-45 months). Permanent drainage route was performed in 1 case which communicated with sphenoid sinus. While the other 2 cases which drained to pharyngeal recess resulted in drainage route blocking within the 3-6 months after surgery, but without obvious symptoms. This procedure for the drainage of petrous apex cholesterol granuloma showed to be effective, safe and minimally invasive. Although there is no recurrence in short-term, however, long-term surveillance and large case series are necessary, especially to the maitainence of permanent drainage.

Endoscopic ultrasound-guided placement of plastic vs. biflanged metal stents for therapy of walled-off necrosis: a retrospective single-center series.

PubMed

Mukai, Shuntaro; Itoi, Takao; Baron, Todd H; Sofuni, Atsushi; Itokawa, Fumihide; Kurihara, Toshio; Tsuchiya, Takayoshi; Ishii, Kentaro; Tsuji, Shujiro; Ikeuchi, Nobuhito; Tanaka, Reina; Umeda, Junko; Tonozuka, Ryosuke; Honjo, Mitsuyoshi; Gotoda, Takuji; Moriyasu, Fuminori; Yasuda, Ichiro

2015-01-01

Recently, a novel fully covered and biflanged metal stent (BFMS)dedicated to the drainage of walled-off necrosis(WON) was developed. The aim of this study was to retrospectively evaluate the safety, efficacy, and cost performance of drainage of WON using the novel BFMS compared with a traditional plastic stent. A total of 70 patients with symptomatic WON were treated under endoscopic ultrasound (EUS) guidance. Initial drainage was conducted using the single gateway technique with placement of one or more plastic stents or a single BFMS.If drainage was unsuccessful,direct endoscopic necrosectomy (DEN)was performed. There were no statistically significant differences in rates of technical success, clinical success,and adverse events between plastics stents and BFMS, despite the size of WON in the BFMS group being significantly larger than that in the plastic stent group (105.6 vs. 77.1 mm; P=0.003).The mean procedure times for the first EUS-guided drainage and for re-intervention were significantly shorter in the BFMS group than in the plastic stent group (28.8±7.1 vs. 42.6±14.2, respectively,for drainage, P<0.001; and 34.9±8.5 vs.41.8±7.6, respectively, for re-intervention, P<0.001). There was no statistically significant difference in the total cost between plastic stent and BFMS use in the treatment of WON ($5352vs. $6274; P=0.25). Plastic stents and BFMS were safe and effective for the treatment of WON. In particular,BFMS placement appeared to be preferable for initial EUS-guided drainage and additional reintervention(e.g. DEN) as it reduced the procedure time. Prospective randomized controlled trials are warranted.

Long-term results after endoscopic drainage and necrosectomy of symptomatic pancreatic fluid collections.

PubMed

Seewald, Stefan; Ang, Tiing Leong; Richter, Hugo; Teng, Karl Yu Kim; Zhong, Yan; Groth, Stefan; Omar, Salem; Soehendra, Nib

2012-01-01

To determine the immediate and long-term results of endoscopic drainage and necrosectomy for symptomatic pancreatic fluid collections. The data of 80 patients with symptomatic pancreatic fluid collections (mean diameter: 11.7 cm, range 3-20; pseudocysts: 24/80, abscess: 20/80, infected walled-off necrosis: 36/80) referred for endoscopic management from October 1997 to March 2008 were analyzed retrospectively. Endoscopic drainage techniques included endoscopic ultrasound (EUS)-guided aspiration (2/80), EUS-guided transenteric drainage (70/80) and non-EUS-guided drainage across a spontaneous transenteric fistula (8/80). Endoscopic necrosectomy was carried out in 49/80 (abscesses: 14/20; infected necrosis: 35/36). Procedural complications were bleeding (12/80), perforation (7/80), portal air embolism (1/80) and Ogilvie Syndrome (1/80). Initial technical success was achieved in 78/80 (97.5%) and clinical resolution of the collections was achieved endoscopically in 67/80 (83.8%), with surgery required in 13/80 (perforation: four; endoscopically inaccessible areas: two; inadequate drainage: seven). Within 6 months five patients required surgery due to recurrent fluid collections; over a mean follow up of 31 months, surgery was required in four more patients due to recurrent collections as a consequence of underlying pancreatic duct abnormalities that could not be treated endoscopically. The long-term success of endoscopic treatment was 58/80 (72.5%). Endoscopic drainage of symptomatic pancreatic fluid collections is safe and effective, with excellent immediate and long-term results. Endoscopic necrosectomy has a risk of serious complications. The underlying pancreatic duct abnormalities must be addressed to prevent recurrence of fluid collections. © 2011 The Authors. Digestive Endoscopy © 2011 Japan Gastroenterological Endoscopy Society.

Negative pressure irrigation and endoscopic necrosectomy through man-made sinus tract in infected necrotizing pancreatitis: a technical report.

PubMed

Tong, Zhihui; Ke, Lu; Li, Baiqiang; Li, Gang; Zhou, Jing; Shen, Xiao; Li, Weiqin; Li, Ning; Li, Jieshou

2016-11-10

In recent years, a step-up approach based on minimally invasive techniques was recommended by latest guidelines as initial invasive treatment for infected pancreatic necrosis (IPN). In this study, we aimed to describe a novel step-up approach for treating IPN consisting of four steps including negative pressure irrigation (NPI) and endoscopic necrosectomy (ED) as a bridge between percutaneous catheter drainage (PCD) and open necrosectomy METHODS: A retrospective review of a prospectively collected internal database of patients with a diagnosis of IPN between Jan, 2012 to Dec, 2012 at a single institution was performed. All patients underwent the same drainage strategy including four steps: PCD, NPI, ED and open necrosectomy. The demographic characteristics and clinical outcomes of study patients were analyzed. A total of 71 consecutive patients (48 males and 23 females) were included in the analysis. No significant procedure-related complication was observed and the overall mortality was +21.1 % (15 of 71 patients). Seven different strategies like PCD+ NPI, PCD+NPI+ED, PCD+open necrosectomy, etcetera, were applied in study patients and a half of them received PCD alone. In general, each patient underwent a median of 2 drainage procedures and the median total drainage duration was 11 days (interquartile range, 6-21days). This four-step approach is effective in treating IPN and adds no extra risk to patients when compared with other latest step-up strategies. The two novel techniques (NPI and ED) could offer distinct clinical benefits without posing unanticipated risks inherent to the procedures.

Short-Term Effect of Autogenic Drainage on Ventilation Inhomogeneity in Adult Subjects With Stable Non-Cystic Fibrosis Bronchiectasis.

PubMed

Poncin, William; Reychler, Grégory; Leeuwerck, Noémie; Bauwens, Nathalie; Aubriot, Anne-Sophie; Nader, Candice; Liistro, Giuseppe; Gohy, Sophie

2017-05-01

Lung clearance index (LCI), a measure of ventilation inhomogeneity derived from a multiple-breath washout test, is a promising tool for assessing airway function in patients with non-cystic fibrosis bronchiectasis. However, it is unknown whether ventilation inhomogeneity could improve after successful elimination of excessive secretions within bronchiectasis. The objective of this work was to assess the short-term effects of lung secretion clearance using the autogenic drainage technique on standard lung function tests and LCI in subjects with non-cystic fibrosis bronchiectasis. Nitrogen-based multiple-breath washout, spirometry, and body plethysmography tests were performed 30 min before autogenic drainage in adults with stable non-cystic fibrosis bronchiectasis. The autogenic drainage session was followed by a 5-min break, after which the tests were repeated in the same order. Sputum expectorated during autogenic drainage was quantified as dry weight and correlated with change between post- and pre-measurements (Δ). Paired t test or Wilcoxon signed-rank tests were used to compare pre- and post-autogenic drainage measurement outcomes. A P value of ≤.05 was considered as statistically significant. Twenty-four subjects were studied (18 females, median age [range]: 65 [21-81] y). Mean ± SD LCI significantly improved after autogenic drainage (10.88 ± 2.62 vs 10.53 ± 2.35, P = .042). However, only 20% of subjects with mucus hyperproduction during autogenic drainage had a ΔLCI that exceeded measurement variability. The percent of predicted slow vital capacity (SVC%) also slightly improved (88.7 ± 19.3% vs 90 ± 19.1%, P = .02). ΔLCI was inversely related to dry sputum weight (r = -.48, P = .02) and ΔSVC% (r = -.64, P = .001). ΔSVC% also correlated with dry sputum weight (r = 0.46, P = .02). In adults with non-cystic fibrosis bronchiectasis and mucus hypersecretion, autogenic drainage improved ventilation inhomogeneity. LCI change may be the result of the maximum recruited lung volume and the amount of cleared mucus secretion. (ClinicalTrials.gov registration NCT02411981.). Copyright © 2017 by Daedalus Enterprises.

Ventral marsupialisation in the treatment of gastric dilatation-volvulus in two dogs.

PubMed

Mills, J

2000-06-01

A ventral marsupialisation technique is described which was used successfully to manage gastric dilatation-volvulus (GDV) in two large breed dogs. The procedure allowed the stomach to be completely and rapidly emptied and lavaged without peritoneal contamination. Drainage was maintained in the postoperative period for both dogs and the technique was expected to result in a permanent ventral gastropexy.

Percutaneous transhepatic bile drainage.

PubMed Central

Mori, K; Misumi, A; Sugiyama, M; Okabe, M; Matsuoka, T

1977-01-01

Percutaneous transhepatic bile drainage was performed in 13 patients with obstructive jaundice, using a combination of the PTC technique and a Seldinger angiography catheter. In 11 cases, the outflow of bile through the catheter was satisfactory and complications were few. Since the risk of the procedure is low and it can be done without laparotomy, it is an ideal technic for biliary decompression before attempting to do a resection. Also, repeated cholangiography through a catheter which is left in place is helpful as a diagnostic aid before and after surgery. Images Fig. 3. Fig. 4. Fig. 5. Fig. 6. PMID:831630

Improvement effect on the depth-dose distribution by CSF drainage and air infusion of a tumour-removed cavity in boron neutron capture therapy for malignant brain tumours

NASA Astrophysics Data System (ADS)

Sakurai, Yoshinori; Ono, Koji; Miyatake, Shin-ichi; Maruhashi, Akira

2006-03-01

Boron neutron capture therapy (BNCT) without craniotomy for malignant brain tumours was started using an epi-thermal neutron beam at the Kyoto University Reactor in June 2002. We have tried some techniques to overcome the treatable-depth limit in BNCT. One of the effective techniques is void formation utilizing a tumour-removed cavity. The tumorous part is removed by craniotomy about 1 week before a BNCT treatment in our protocol. Just before the BNCT irradiation, the cerebro-spinal fluid (CSF) in the tumour-removed cavity is drained out, air is infused to the cavity and then the void is made. This void improves the neutron penetration, and the thermal neutron flux at depth increases. The phantom experiments and survey simulations modelling the CSF drainage and air infusion of the tumour-removed cavity were performed for the size and shape of the void. The advantage of the CSF drainage and air infusion is confirmed for the improvement in the depth-dose distribution. From the parametric surveys, it was confirmed that the cavity volume had good correlation with the improvement effect, and the larger effect was expected as the cavity volume was larger.

Improvement effect on the depth-dose distribution by CSF drainage and air infusion of a tumour-removed cavity in boron neutron capture therapy for malignant brain tumours.

PubMed

Sakurai, Yoshinori; Ono, Koji; Miyatake, Shin-Ichi; Maruhashi, Akira

2006-03-07

Boron neutron capture therapy (BNCT) without craniotomy for malignant brain tumours was started using an epi-thermal neutron beam at the Kyoto University Reactor in June 2002. We have tried some techniques to overcome the treatable-depth limit in BNCT. One of the effective techniques is void formation utilizing a tumour-removed cavity. The tumorous part is removed by craniotomy about 1 week before a BNCT treatment in our protocol. Just before the BNCT irradiation, the cerebro-spinal fluid (CSF) in the tumour-removed cavity is drained out, air is infused to the cavity and then the void is made. This void improves the neutron penetration, and the thermal neutron flux at depth increases. The phantom experiments and survey simulations modelling the CSF drainage and air infusion of the tumour-removed cavity were performed for the size and shape of the void. The advantage of the CSF drainage and air infusion is confirmed for the improvement in the depth-dose distribution. From the parametric surveys, it was confirmed that the cavity volume had good correlation with the improvement effect, and the larger effect was expected as the cavity volume was larger.

Laparoscopic drainage of hematocolpos: a new treatment option for the acute management of a transverse vaginal septum.

PubMed

Dennie, Joëlle; Pillay, Sunil; Watson, David; Grover, Sonia

2010-10-01

To describe a novel technique for the acute management of a transverse vaginal septum with hematocolpos. Retrospective case series. Secondary- and tertiary-care centers in Australia and New Zealand. Three patients with a transverse vaginal septum presenting with pain and a hematocolpos. Laparoscopic drainage of the hematocolpos. Pain relief until definitive resection of the transverse vaginal septum. All patients were free of pain after the procedure. Two patients had a second laparoscopic procedure to drain the hematocolpos which had reaccumulated while awaiting definitive surgery. All three patients have undergone resection of the septum. Laparoscopic drainage provides a novel approach to the acute management of a transverse vaginal septum, providing pain relief without compromising the success of definitive surgery which can be performed at a later date. Copyright © 2010 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Catheter drainage of pleural fluid collections and pneumothorax.

PubMed

Frendin, J; Obel, N

1997-06-01

A technique for virtually atraumatic placement of small size chest catheters for suction drainage of pleural effusions and pneumothorax in the dog and cat is described. Thirty-nine dogs and two cats were treated for pyothorax (10 cases), hydrothorax (eight), chylothorax (three), haemothorax (three), haemothorax/ pneumothorax (three) and pneumothorax (14). In all 41 cases, thin or viscous fluid and/or air were efficiently drained. The mean period of drainage was four days (range, 0.5 to 18 days). The average amount of fluid removed from each patient in 24 hours was 530 ml in pyothorax cases (range, 140 to 1100 ml) and 1300 ml in the other cases (range, 20 to 5000 ml). In 40 cases there were no complications related to the procedure. One dog with severe pleural adhesions was euthanased because of lung perforation and pneumothorax secondary to misplacement of the catheter.

Percutaneous transgastric irrigation drainage in combination with endoscopic necrosectomy in necrotizing pancreatitis (with videos).

PubMed

Raczynski, Susanne; Teich, Niels; Borte, Gudrun; Wittenburg, Henning; Mössner, Joachim; Caca, Karel

2006-09-01

Endoscopic drainage of pancreatic acute and chronic pseudocysts and pancreatic necrosectomy have been shown to be beneficial for critically ill patients, with complete endoscopic resolution rates of around 80%. Our purpose was to describe an improved endoscopic technique used to treat pancreatic necrosis. Case report. University hospital. Two patients with large retroperitoneal necroses were treated with percutaneous transgastric retroperitoneal flushing tubes and a percutaneous transgastric jejunal feeding tube by standard percutaneous endoscopic gastrostomy access in addition to endoscopic necrosectomy. Intensive percutaneous transgastric flushing in combination with percutaneous normocaloric enteral nutrition and repeated endoscopic necrosectomy led to excellent outcomes in both patients. Small number of patients. The "double percutaneous endoscopic gastrostomy" approach for simultaneous transgastric drainage and normocaloric enteral nutrition in severe cases of pancreatic necroses is safe and effective. It could be a promising improvement to endoscopic transgastric treatment options in necrotizing pancreatitis.

Experimental Investigation of Hysteretic Dynamic Capillarity Effect in Unsaturated Flow

PubMed Central

Zhuang, Luwen; Qin, Chao‐Zhong; de Waal, Arjen

2017-01-01

Abstract The difference between average pressures of two immiscible fluids is commonly assumed to be the same as macroscopic capillary pressure, which is considered to be a function of saturation only. However, under transient conditions, a dependence of this pressure difference on the time rate of saturation change has been observed by many researchers. This is commonly referred to as dynamic capillarity effect. As a first‐order approximation, the dynamic term is assumed to be linearly dependent on the time rate of change of saturation, through a material coefficient denoted by τ. In this study, a series of laboratory experiments were carried out to quantify the dynamic capillarity effect in an unsaturated sandy soil. Primary, main, and scanning drainage experiments, under both static and dynamic conditions, were performed on a sandy soil in a small cell. The value of the dynamic capillarity coefficient τ was calculated from the air‐water pressure differences and average saturation values during static and dynamic drainage experiments. We found a dependence of τ on saturation, which showed a similar trend for all drainage conditions. However, at any given saturation, the value of τ for primary drainage was larger than the value for main drainage and that was in turn larger than the value for scanning drainage. Each data set was fit a simple log‐linear equation, with different values of fitting parameters. This nonuniqueness of the relationship between τ and saturation and possible causes is discussed. PMID:29398729

Experimental Investigation of Hysteretic Dynamic Capillarity Effect in Unsaturated Flow

NASA Astrophysics Data System (ADS)

Zhuang, Luwen; Hassanizadeh, S. Majid; Qin, Chao-Zhong; de Waal, Arjen

2017-11-01

The difference between average pressures of two immiscible fluids is commonly assumed to be the same as macroscopic capillary pressure, which is considered to be a function of saturation only. However, under transient conditions, a dependence of this pressure difference on the time rate of saturation change has been observed by many researchers. This is commonly referred to as dynamic capillarity effect. As a first-order approximation, the dynamic term is assumed to be linearly dependent on the time rate of change of saturation, through a material coefficient denoted by τ. In this study, a series of laboratory experiments were carried out to quantify the dynamic capillarity effect in an unsaturated sandy soil. Primary, main, and scanning drainage experiments, under both static and dynamic conditions, were performed on a sandy soil in a small cell. The value of the dynamic capillarity coefficient τ was calculated from the air-water pressure differences and average saturation values during static and dynamic drainage experiments. We found a dependence of τ on saturation, which showed a similar trend for all drainage conditions. However, at any given saturation, the value of τ for primary drainage was larger than the value for main drainage and that was in turn larger than the value for scanning drainage. Each data set was fit a simple log-linear equation, with different values of fitting parameters. This nonuniqueness of the relationship between τ and saturation and possible causes is discussed.

Water quality function of an extensive vegetated roof.

PubMed

Todorov, Dimitar; Driscoll, Charles T; Todorova, Svetoslava; Montesdeoca, Mario

2018-06-01

In this paper we present the results of a four-year study of water quality in runoff from an extensive, sedum covered, vegetated roof on an urban commercial building. Monitoring commenced seven months after the roof was constructed, with the first growing season. Stormwater drainage quality function of the vegetated roof was compared to a conventional (impermeable, high-albedo) membrane roof in addition to paired measurements of wet and bulk depositions at the study site. We present concentrations and fluxes of nutrients and major solutes. We discuss seasonal and year-to-year variation in water quality of drainage from the vegetated roof and how it compares with atmospheric deposition and drainage from the impermeable roof. Drainage waters from the vegetated roof exhibited a high concentration of nutrients compared to atmospheric deposition, particularly during the warm temperature growing season. However, nutrient losses were generally low because of the strong retention of water by the vegetated roof. There was marked variation in the retention of nutrients by season due to variations in concentrations in drainage from the vegetated roof. The vegetated roof was a sink of nitrogen, total phosphorus and chloride, and a source of phosphate and dissolved inorganic and organic carbon. Chloride exhibited elevated inputs and leaching during the winter. The drainage from the vegetated and impermeable roofs met the United States Environmental Protection Agency freshwater standards for all parameters, except for total phosphorus. Copyright © 2017 Elsevier B.V. All rights reserved.

Percutaneous drainage of Morel-Lavallée lesions when the diagnosis is delayed.

PubMed

Zhong, Biao; Zhang, Chi; Luo, Cong-feng

2014-10-01

Morel-Lavallée lesions are a closed internal degloving, and open débridement can damage the only remaining blood supply to the skin. We performed percutaneous draining and débridement to treat 8 patients in whom the diagnosis of Morel-Lavallée lesions was delayed more than 1 week. Here we discuss our treatment procedures and the outcomes in these 8 patients. We consider percutaneous drainage to be an effective treatment for patients with delayed diagnosis of Morel-Lavallée lesions.

Destruction of the ecosystem in the Great Lakes and possibilities for its reconstruction

USGS Publications Warehouse

Smith, Stanford H.; Moore, Remedios W.

1972-01-01

This paper is a review of the sequence of events within the Great Lakes and their drainage to provide a basis for interpreting probable cause-and-effect relations between events of settlement and changes in the ecosystem of the Great Lakes. Possibilities of restoration of the lakes are discussed. A plan to do so must include (1) improvement of land uses in the drainage basin, (2) elimination of sources of physical, chemical, and biological pollution entering the lakes, and (3) restoration of favorable and productive fish populations.

Imaging and interventions in hilar cholangiocarcinoma: A review

PubMed Central

Madhusudhan, Kumble Seetharama; Gamanagatti, Shivanand; Gupta, Arun Kumar

2015-01-01

Hilar cholangiocarcinoma is a common malignant tumor of the biliary tree. It has poor prognosis with very low 5-year survival rates. Various imaging modalities are available for detection and staging of the hilar cholangiocarcinoma. Although ultrasonography is the initial investigation of choice, imaging with contrast enhanced computed tomography scan or magnetic resonance imaging is needed prior to management. Surgery is curative wherever possible. Radiological interventions play a role in operable patients in the form of biliary drainage and/or portal vein embolization. In inoperable cases, palliative interventions include biliary drainage, biliary stenting and intra-biliary palliative treatment techniques. Complete knowledge of application of various imaging modalities available and about the possible radiological interventions is important for a radiologist to play a critical role in appropriate management of such patients.We review the various imaging techniques and appearances of hilar cholangiocarcinoma and the possible radiological interventions. PMID:25729485

Subdural drainage versus subperiosteal drainage in burr-hole trepanation for symptomatic chronic subdural hematomas.

PubMed

Bellut, David; Woernle, Christoph Michael; Burkhardt, Jan-Karl; Kockro, Ralf Alfons; Bertalanffy, Helmut; Krayenbühl, Niklaus

2012-01-01

Symptomatic chronic subdural hematoma (scSDH) is one of the most frequent diseases in neurosurgical practice, and its incidence is increasing. However, treatment modalities are still controversial. The aim of this retrospective single-center study is to compare for the first time two surgical methods in the treatment of subdural hematoma that have been proven to be efficient in previous studies in a direct comparison. We analyzed the data of 143 scSDHs in 113 patients undergoing surgery for subdural hematoma with placement of subperiosteal or subdural drainage after double burr-hole trepanation for hematoma evacuation. Overall, there were no statistically significant differences regarding general patient characteristics, preoperative and postoperative symptoms, postoperative hematoma remnant, rates of recurrences, mortality, complications, and outcome at discharge and at 3-month follow up between the groups. There was a close to significant tendency of lower mortality after placement of subperiosteal drainage system and a tendency towards lower rate of recurrent hematoma after placement of subdural drainage system. Our study shows for the first time a direct comparison of two mainly used surgical techniques in the treatment of scSDH. Both methods proved to be highly effective, and general patient data, complications, outcome and mortality of both groups are equal or superior compared with previously published series. Because there is a clear tendency to less mortality and fewer serious complications, treatment with double burr-hole trepanation, irrigation, and placement of subperiosteal drainage is our treatment of choice in patients with predictable high risk of complications. Copyright © 2012 Elsevier Inc. All rights reserved.

CT guided transthoracic catheter drainage of intrapulmonary abscess.

PubMed

Yunus, Mahira

2009-10-01

To determine the efficacy of CT- guided transthoracic catheter drainage of intrapulmonary abscess considering success rate versus complications. This prospective study was carried out at radiology department of Al-Noor Specialist Hospital, Makkah, Saudi Arabia, from 1.1.2003 to 31.12.2005. Nineteen patients were selected for CT guided percutaneous drainage. Under CT guidance catheter placement was carried out using Seldinger technique. Nineteen patients with lung abscess were selected for the percutaneous CT guided drainage. Eight (42.105%) patients encountered no complications and lung abscess completely resolved with no residual cavity. Five (26.31%) patients developed pneumothorax, which was the most common complication of this study. These patients were kept under observation and followed-up by chest X-rays. Three (15.78%) had mild pneumothorax, which resolved and needed no further management, while two (10.52%) patients developed moderate pneumothorax and chest tube was inserted. Two (10.52%) patients developed mild haemoptysis which resolved within two hours, hence, no further management was required. Two (10.52%) patients had residual cavity and surgery was performed. Congenital cystic adenomatoid malformation (CCAM) was found in both cases. Two patients out of nineteen patients (10.52%) developed bronchopleural fistula and were operated. No mortality occurred during or after the procedure. CT allows optimal placement of catheter and hence enables safe and effective percutaneous evacuation of lung abscess. The morbidity and mortality of patients with percutaneous catheter drainage is lower than with surgical resection. Hence, CT guided drainage should be considered the first therapeutic choice in most patients of lung abscess who do not respond to medical therapy.

Large-Scale Effects of Timber Harvesting on Stream Systems in the Ouachita Mountains, Arkansas, USA

NASA Astrophysics Data System (ADS)

Williams, Lance R.; Taylor, Christopher M.; Warren, Melvin L., Jr.; Clingenpeel, J. Alan

2002-01-01

Using Basin Area Stream Survey (BASS) data from the United States Forest Service, we evaluated how timber harvesting influenced patterns of variation in physical stream features and regional fish and macroinvertebrate assemblages. Data were collected for three years (1990-1992) from six hydrologically variable streams in the Ouachita Mountains, Arkansas, USA that were paired by management regime within three drainage basins. Specifically, we used multivariate techniques to partition variability in assemblage structure (taxonomic and trophic) that could be explained by timber harvesting, drainage basin differences, year-to-year variability, and their shared variance components. Most of the variation in fish assemblages was explained by drainage basin differences, and both basin and year-of-sampling influenced macroinvertebrate assemblages. All three factors modeled, including interactions between drainage basins and timber harvesting, influenced variability in physical stream features. Interactions between timber harvesting and drainage basins indicated that differences in physical stream features were important in determining the effects of logging within a basin. The lack of a logging effect on the biota contradicts predictions for these small, hydrologically variable streams. We believe this pattern is related to the large scale of this study and the high levels of natural variability in the streams. Alternatively, there may be time-specific effects we were unable to detect with our sampling design and analyses.

Genetic variation in westslope cutthroat trout Oncorhynchusclarkii lewisi: implications for conservation

USGS Publications Warehouse

Daniel P. Drinan,; Kalinowski, Steven T.; Vu, Ninh V.; Shepard, Bradley B.; Muhlfeld, Clint C.; Campbell, Matthew R.

2011-01-01

Twenty-five populations of westslope cutthroat trout from throughout their native range were genotyped at 20 microsatellite loci to describe the genetic structure of westslope cutthroat trout. The most genetic diversity (heterozygosity, allelic richness, and private alleles) existed in populations from the Snake River drainage, while populations from the Missouri River drainage had the least. Neighbor-joining trees grouped populations according to major river drainages. A great amount of genetic differentiation was present among and within all drainages. Based on Nei’s DS, populations in the Snake River were the most differentiated, while populations in the Missouri River were the least. This pattern of differentiation is consistent with a history of sequential founding events through which westslope cutthroat trout may have experienced a genetic bottleneck as they colonized each river basin from the Snake to the Clark Fork to the Missouri river. These data should serve as a starting point for a discussion on management units and possible distinct population segments. Given the current threats to the persistence of westslope cutthroat trout, and the substantial genetic differentiation between populations, these topics warrant attention.

Use of Gastrointestinal Anastomosis Stapler for Harvest of Gracilis Muscle and Securing It in the Face for Facial Reanimation: A Novel Technique

PubMed Central

Shridharani, Sachin M.; Stapleton, Sahael M.; Redett, Richard J.; Magarakis, Michael; Rosson, Gedge D.

2010-01-01

Background: The primary objective of this study is to report a novel technique that uses the gastrointestinal anastomosis (GIA) stapler for harvesting and securing the gracilis muscle in facial reanimation surgery. Methods: We conducted a retrospective chart review with 18 consecutive patients who underwent gracilis muscle flap transfer with or without the use of a GIA stapler. Results: Of 11 operations with the GIA stapler, one patient developed a hematoma (donor site) and another required drainage of an abscess (recipient site). Of 8 operations without the use of the stapler, one patient had total flap failure and three required drainage of an abscess (2 recipient sites and 1 donor site). These differences trended toward improvement but were not statistically different. Conclusions: The use of the GIA stapler is a fast, safe technique. Larger studies are, however, warranted to further examine this novel approach in order to test precisely what factors of increased efficiency occur, the amount of suture pull-through, and overall tension capable of being applied to the secured staple line. PMID:20396379

Liquid redistribution behind a drainage front in porous media imaged by neutron radiography

NASA Astrophysics Data System (ADS)

Hoogland, Frouke; Lehmann, Peter; Moebius, Franziska; Vontobel, Peter; Or, Dani

2013-04-01

Drainage from porous media is a highly dynamic process involving the motion of a displacement front with rapid pore scale interfacial jumps and phase entrapment, but also a more gradual host of liquid redistribution processes in the unsaturated region behind the front. Depending on the velocity of the drainage process, liquid properties and the permeability of the porous medium, redistribution lingers long after the main drainage process is stopped, until gravity and capillary forces regain equilibrium. The rapid and often highly inertial Haines jumps at the drainage front challenge the validity of Buckingham-Darcy law and thus representation of the process based on the foundation of Richards equation. To quantify front displacement and liquid reconfiguration and to test validity of Richards equation with respect to fast drainage dynamics, we carried out drainage experiments by withdrawing water from the bottom of initially saturated sand-filled Hele-Shaw cells at constant water flux (2.6 or 13.1 mm/minute). Water content distribution and evolution of drainage front were measured with neutron radiography at spatial and temporal resolutions of 0.1 mm and 3 seconds, respectively. Water pressure was measured above and below the front using pressure transducers and a tensiometer. After the pump was stopped (at a front depth around 100 mm), capillary pressure values in the unsaturated region (above the front) gradually converged to a new equilibrium. The pressure signal in the saturated region below the front reflected viscous losses during flow that were relaxed when the pump stopped. During pressure relaxation water was redistributed primarily downward in the unsaturated region. Pressure signals and dynamics of water content profiles for fast process (13.6 mm/minute) could not be reproduced with Richards equation based on hydraulic functions determined in preceding laboratory experiments. To explore if the deviations stem from inappropriate hydraulic functions we redefined them based on fitting the slow experiment (2.6 mm/min) and apply the optimized functions for the fast experiment. Finally we will discuss application of alternative formulation based on foam drainage equation to represent liquid redistribution dynamics behind the front.

Specific Yield--Column drainage and centrifuge moisture content

USGS Publications Warehouse

Johnson, A.I.; Prill, R.C.; Morris, D.A.

1963-01-01

The specific yield of a rock or soil, with respect to water, is the ratio of (1) the volume of water which, after being saturated, it will yield by gravity to (2) its own volume. Specific retention represents the water retained against gravity drainage. The specific yield and retention when added together are equal to the total interconnected porosity of the rock or soil. Because specific retention is more easily determined than specific yield, most methods for obtaining yield first require the determination of specific retention. Recognizing the great need for developing improved methods of determining the specific yield of water-bearing materials, the U.S. Geological Survey and the California Department of Water Resources initiated a cooperative investigation of this subject. The major objectives of this research are (1) to review pertinent literature on specific yield and related subjects, (2) to increase basic knowledge of specific yield and rate of drainage and to determine the most practical methods of obtaining them, (3) to compare and to attempt to correlate the principal laboratory and field methods now commonly used to obtain specific yield, and (4) to obtain improved estimates of specific yield of water-bearing deposits in California. An open-file report, 'Specific yield of porous media, an annotated bibliography,' by A. I. Johnson, D. A. Morris, and R. C. Prill, was released in 1960 in partial fulfillment of the first objective. This report describes the second phase of the specific-yield study by the U.S. Geological Survey Hydrologic Laboratory at Denver, Colo. Laboratory research on column drainage and centrifuge moisture equivalent, two methods for estimating specific retention of porous media, is summarized. In the column-drainage study, a wide variety of materials was packed into plastic columns of 1- to 8-inch diameter, wetted with Denver tap water, and drained under controlled conditions of temperature and humidity. The effects of cleaning the porous media; of different column diameters; of dye and time on drainage; and of different methods of drainage, wetting, and packing were all determined. To insure repeatability of porosity in duplicate columns, a mechanical technique of packing was developed. In the centrifuge moisture-content study, the centrifuge moisture-equivalent (the moisture content retained by a soil that has been first saturated and then subjected to a force equal to 1,000 times the force of gravity for 1 hour) test was first reviewed and evaluated. It was determined that for reproducible moisture-retention results the temperature and humidity should be controlled by use of a controlled-temperature centrifuge. In addition to refining this standard test, the study determined the effect of length of period of centrifuging and of applied tension on the drainage results. The plans for future work require the continuation of the laboratory standardization study qith emphasis on investigation of soil-moisture tension and unsaturated-permeability techniques. A detailed study in the field then will be followed by correlation and evaluation of laboratory and field methods.

Intraventricular catheter placement by electromagnetic navigation safely applied in a paediatric major head injury patient.

PubMed

Aufdenblatten, Christoph Alexander; Altermatt, Stefan

2008-09-01

In the management of severe head injuries, the use of intraventricular catheters for intracranial pressure (ICP) monitoring and the option of cerebrospinal fluid drainage is gold standard. In children and adolescents, the insertion of a cannula in a compressed ventricle in case of elevated intracranial pressure is difficult; therefore, a pressure sensor is placed more often intraparenchymal as an alternative option. In cases of persistent elevated ICP despite maximal brain pressure management, the use of an intraventricular monitoring device with the possibility of cerebrospinal fluid drainage is favourable. We present the method of intracranial catheter placement by means of an electromagnetic navigation technique.

Stressful Situations of Air Force Nurses Recently Graduated from Pre-Service Baccalaureate Programs in Nursing as Identified by Critical Incident Technique.

DTIC Science & Technology

1980-01-01

and woke up very lucid and stated, "I’m going to have a craniotomy --the brain is a very delicate organ." I answered, "Yes, you are going to have the...who had pneumonia. She was to get per- cussion and postural drainage every 4 hours. 2. I had made sure the tech. caring for her knew about the...percussion and postural drainage and had asked at noon if it was done for the morning and at 1500 if it was done for the afternoon. Both times the tech said

[Distal stenosis of the choledochus in chronic pancreatitis: endoscopic drainage or operation?].

PubMed

Meyer, W; Bödeker, H; Schönekäs, H; Gebhardt, C

1996-09-01

With the less invasive techniques for complications regarding chronic pancreatitis, such as tubular choledochostenosis, the endoscopic transpapillary bile drainage therapy by means of endoprosthesis has undergone an enlargement of its indications range. Blocked and dislocated prostheses, however, further raise the already existing possibility of septic complications. With 15 out of 43 patients undergoing medium-term endodrainage treatment, we observed different resulting conditions of chronic cholestasis, such as abscess-forming cholangitis, hepatic abscesses, retroperitoneal phlegmon and sepsis up to biliary cirrhosis. Thus, in the case of chronic pancreatitis we still regard choledochostenosis- which, due to scarring, is mostly fixed-as a primary indication for operation.

Management of Recurrent Subdural Hematomas.

PubMed

Desai, Virendra R; Scranton, Robert A; Britz, Gavin W

2017-04-01

Subdural hematomas commonly recur after surgical evacuation, at a rate of 2% to 37%. Risk factors for recurrence can be patient related, radiologic, or surgical. Patient-related risk factors include alcoholism, seizure disorders, coagulopathy, and history of ventriculoperitoneal shunt. Radiologic factors include poor brain reexpansion postoperatively, significant subdural air, greater midline shift, heterogeneous hematomas (layered or multi-loculated), and higher-density hematomas. Surgical factors include lack of or poor postoperative drainage. Most recurrent hematomas are managed successfully with burr hole craniostomies with postoperative closed-system drainage. Refractory hematomas may be managed with a variety of techniques, including craniotomy or subdural-peritoneal shunt placement. Copyright © 2016 Elsevier Inc. All rights reserved.

The application of remote sensing technology to the solution of problems in the management of resources in Indiana

NASA Technical Reports Server (NTRS)

Weismiller, R. A.; Mroczynski, R. P. (Principal Investigator)

1978-01-01

The author has identified the following significant results. Of the sampling techniques considered, a combination soil mapping and area sampling offered the most practical method for gathering soils data. Using the dot grid count, a relative percentage composition of soils can be calculated for each spectral class. From these percentages, a legend describing the dominant soils and inclusions can be developed. Interval drainage class seemed to be correlated with magnitude. For every parent material area, the more poorly drained soils had a lower magnitude of reflectance. Soil spectral classes seemed to be predominantly one internal drainage class.

Endoscopic treatment of large pancreatic fluid collections (PFC) using self-expanding metallic stents (SEMS) - a two-center experience.

PubMed

Chaves, Dalton Marques; Mönkemüller, Klaus; Carneiro, Fred; Medrado, Bruno; Dos Santos, Marcos; Wodak, Stephanie; Reimão, Sílvia; Sakai, Paulo; de Moura, Eduardo

2014-12-01

Background/study aim: During the last several years, endoscopic ultrasound (EUS)-guided pancreatic fluid collections' (PFC) drainage has evolved into the preferred drainage technique. Recently, self-expanding metallic stents (SEMS) have been used as an alternative to double pigtail stents, with the advantage of providing a larger diameter fistula, thereby decreasing the risk of early obstruction and also allowing for direct endoscopic exploration of the cavity. The aim of this study was to evaluate the technical and clinical success, safety, and outcome of patients undergoing EUS-guided drainage of complex PFC using SEMS. The study was conducted at two tertiary hospitals from January 2010 to January 2013. All patients with PFC referred for endoscopic drainage were enrolled in a prospective database. The inclusion criteria were: (1) patients with pseudocysts or walled-off necrosis based on the revised Atlanta classification; (2) symptomatic patients with thick PFC; (3) PFC that persisted more than 6 weeks; and (4) large PFC diameter (≥ 9 cm). The exclusion criteria consisted of coagulation disorders, PFC bleeding or infection, and failure-to-inform written consent. A total of 16 patients (9 females, 7 males; mean age 52.6, range 20 - 82) underwent EUS drainage with SEMS. There were 14 cases of pseudocysts and 2 cases of walled-off necrosis. The etiologies of the PFC were mainly gallstones (8 of 16 patients, 50 %) and alcohol (5 of 16 patients, 31 %). Technical success was achieved in 100 % of the cases. All patients had a complete resolution of the PFC. Transmural EUS-guided drainage of complex PFC using SEMS is feasible, appears safe, and is efficacious. However, the exchange of the UC (uncovered)-SEMS for plastic stents is mandatory within 1 week. Future prospective studies, preferably multicenter studies, comparing SEMS versus traditional plastic stents for the drainage of PFC are warranted.

Re-plumbing the coast: Untangling the effects of climate change and water management on vulnerability of coastal landscapes to saltwater incursion

NASA Astrophysics Data System (ADS)

Bhattachan, A.; BenDor, T.; Ardón, M.; Bernhardt, E. S.; Wright, J. P.; Emanuel, R. E.

2016-12-01

The Atlantic Coastal Plain of the United States has been altered drastically in the past century to support agriculture, real estate, and recreational activities. In a landscape with minimal hydraulic gradients and potentially large fluctuations in sea level, the effects of introducing artificial drainages (e.g., ditches and canals) on hydrological properties are often drastic and sometimes unpredictable. In this study, we focus on a portion of the outer coastal plain of North Carolina that ranges in elevation between 6 to -5 meters a.m.s.l. To this end, we use a high-resolution, Lidar-derived digital elevation model to study the effects of artificial drainages on landscape elevation, flow accumulation, and drainage density within an 800-km2 study area. Specifically, we use image-processing techniques to filter artificial drainages from the region and compare hydrologically relevant landscape metrics with and without these features. In general, artificial drainages lower land elevation, short-circuit otherwise natural flow paths and lead to increased ( 3 times) drainage density across the landscape. We also calculate a saltwater intrusion vulnerability index (SIVI), with and without canals and ditches, to investigate the contribution of this infrastructure to saltwater intrusion vulnerability in this low-lying coastal region. The SIVI represents the ability of the freshwater to impede the inland migration of saltwater during drought periods or as sea level rises. Our results show that the construction of artificial drainages would in fact lead to an increase in vulnerability to saltwater intrusion and this pattern is consistent across all four major land-cover (wetlands, agriculture, shrub and forest) in our study area. Thus, combined with extant saltwater impacts on freshwater-dependent landscapes across our study area, our findings are immediately relevant to this region and to similar coastal regions worldwide.

Management of cerebrospinal fluid leakage after anterior decompression for ossification of posterior longitudinal ligament in the thoracic spine: the utilization of a volume-controlled pseudomeningocele.

PubMed

Cho, Ji Young; Chan, Chee Keong; Lee, Sang-Ho; Choi, Won-Chul; Maeng, Dae Hyeon; Lee, Ho-Yeon

2012-06-01

Retrospective review To determine the efficacy of management of cerebrospinal fluid (CSF) leakage after the anterior thoracic approach. CSF leakage after incidental durotomy commonly occurs after anterior thoracic ossification of posterior longitudinal ligament (OPLL) surgery. Pseudomeningocele will invariably form under such circumstances. Among them, uncontrolled CSF leakage with a fistulous condition is problematic. As a solution, we have managed these durotomies with chest drains alone without any CSF drainage by the concept of a "volume-controlled pseudomeningocele." Between 2001 and 2009, CSF leakage occurred in 26 patients (37.7%) of the total 69 patients who underwent anterior decompression for thoracic OPLL. In the initial 11 cases, subarachnoid drainage was utilized as an augmentive measure in combination with chest tube drainage in the postoperative period (group A). In the subsequent 15 cases, the durotomy was managed in a similar manner but in the absence of any subarachnoid drainage (group B). Various parameters such as the duration of postoperative hospital stay, clinical outcome score, drainage output, resolution of CSF leakage, complications, and additional surgery performed were analyzed and compared between the 2 groups. A resolution of the CSF leakage grading system was also proposed for the residual pseudomeningocele that formed in each group. There were statistically no significant differences in the outcome parameters between the 2 groups and also in patients with grade I or grade II residual pseudomeningocele of the new grading system. Two complications occurred in group A. No reexploration for persistent CSF leakage was required in both groups. CSF leakage managed with controlled chest tube drainage can produce a comparable result with those with additional subarachnoid drainage when watertight dural repair is impossible. The concept of controlled pseudomeningocele may be a useful and practical technique for the treatment of CSF leakage after anterior thoracic OPLL surgery.

Estimation of Flood Discharges at Selected Recurrence Intervals for Streams in New Hampshire

USGS Publications Warehouse

Olson, Scott A.

2009-01-01

This report provides estimates of flood discharges at selected recurrence intervals for streamgages in and adjacent to New Hampshire and equations for estimating flood discharges at recurrence intervals of 2-, 5-, 10-, 25-, 50-, 100-, and 500-years for ungaged, unregulated, rural streams in New Hampshire. The equations were developed using generalized least-squares regression. Flood-frequency and drainage-basin characteristics from 117 streamgages were used in developing the equations. The drainage-basin characteristics used as explanatory variables in the regression equations include drainage area, mean April precipitation, percentage of wetland area, and main channel slope. The average standard error of prediction for estimating the 2-, 5-, 10-, 25-, 50-, 100-, and 500-year recurrence interval flood discharges with these equations are 30.0, 30.8, 32.0, 34.2, 36.0, 38.1, and 43.4 percent, respectively. Flood discharges at selected recurrence intervals for selected streamgages were computed following the guidelines in Bulletin 17B of the U.S. Interagency Advisory Committee on Water Data. To determine the flood-discharge exceedence probabilities at streamgages in New Hampshire, a new generalized skew coefficient map covering the State was developed. The standard error of the data on new map is 0.298. To improve estimates of flood discharges at selected recurrence intervals for 20 streamgages with short-term records (10 to 15 years), record extension using the two-station comparison technique was applied. The two-station comparison method uses data from a streamgage with long-term record to adjust the frequency characteristics at a streamgage with a short-term record. A technique for adjusting a flood-discharge frequency curve computed from a streamgage record with results from the regression equations is described in this report. Also, a technique is described for estimating flood discharge at a selected recurrence interval for an ungaged site upstream or downstream from a streamgage using a drainage-area adjustment. The final regression equations and the flood-discharge frequency data used in this study will be available in StreamStats. StreamStats is a World Wide Web application providing automated regression-equation solutions for user-selected sites on streams.

Environmental Decision Making on Acid Mine Drainage Issues in South Africa: An Argument for the Precautionary Principle.

PubMed

Morodi, T J; Mpofu, Charles

2017-06-28

This paper examines the issue of acid mine drainage in South Africa and environmental decision making processes that could be taken to mitigate the problem in the context of both conventional risk assessment and the precautionary principle. It is argued that conventional risk assessment protects the status quo and hence cannot be entirely relied upon as an effective tool to resolve environmental problems in the context of South Africa, a developing country with complex environmental health concerns. The complexity of the environmental issues is discussed from historical and political perspectives. An argument is subsequently made that the precautionary principle is an alternative tool, and its adoption can be used to empower local communities. This work, therefore, adds to new knowledge by problematising conventional risk assessment and proposing the framing of the acid mine drainage issues in a complex and contextual scenario of a developing country-South Africa.

Assessing an early modern Fenland population: Whittlesey (Cambridgeshire).

PubMed

Falvey, Heather

2014-01-01

Improvement writers argued that drainage would bring prosperity and population growth to fenland communities; locals counter-argued that their communities were already thriving. The detailed surviving records from early modern Whittlesey, in the Isle of Ely, are analysed here to test the accuracy of these opposing claims. Using the returns of the 1523 Lay Subsidy, the 1563 ecclesiastical census, the Lady Day 1674 Hearth Tax records and the 1676 Compton Census, together with bishops' transcripts and probate inventories, this article finds that although the population did indeed increase after drainage, the pre-drainage population was also increasing. The Michaelmas 1664 Hearth Tax records are analysed to uncover something of the character of the inhabitants and the 1674 Lady Day returns are then used to test the relative wealth of the community compared with that of sub-regions throughout England identified by Tom Arkell. Finally, there is a discussion of Whittlesey's housing stock.

In-situ evaluation of internal drainage in layered soils (Tukulu, Sepane and Swartland)

NASA Astrophysics Data System (ADS)

Mavimbela, S. S. W.; van Rensburg, L. D.

2011-11-01

The soil water release (SWC) and permeability properties of layered soils following deep infiltration depends on the structural and layering composition of the profiles diagnostic horizons. Three layered soils, the Tukulu, Sepane and Swartland soil forms, from the Free State province of South Africa, were selected for internal drainage evaluation. The soil water release curves as a function of suction (h) and unsaturated hydraulic conductivity (K-coefficient) as a function of soil water content, SWC (θ), were characterised alongside the pedological properties of the profiles. The water hanging column in collaboration with the in-situ instantaneous profile method (IPM) was appropriate for this work. Independently, the saturated hydraulic conductivity (Ks) was measured using double ring infiltrometers. The three soils had a generic orthic A horizon but differed remarkable with depth. A clay rich layer was found in the Tukulu and Sepane at depths of 600 to 850 mm and 300 to 900 mm, respectively. The Swartland was weakly developed with a saprolite rock found at depth of 400-700 mm. During the 1200 h drainage period, soil water loss amounted to 21, 20 and 51 mm from the respective Tukulu, Sepane and Swartland profiles. An abrupt drop in Ks in conjunction with a steep K-coefficient gradient with depth was observed from the Tukulu and Sepane. Hydromorphic colours found on the clay-rich horizons suggested a wet soil water regime that implied restriction of internal drainage. It was therefore concluded that the clay rich horizons gave the Tukulu and Sepane soil types restricted internal drainage properties required for soil water storage under infield rainwater harvesting production technique. The coarseness of the Swartland promoted high drainage losses that proliferated a dry soil water regime.

Nonstationary Intensity-Duration-Frequency Curves for Drainge Infrastructure Coping with Climate Change

NASA Astrophysics Data System (ADS)

Kim, Byung Sik; Jeung, Se Jin; Lee, Dong Seop; Han, Woo Suk

2015-04-01

As the abnormal rainfall condition has been more and more frequently happen and serious by climate change and variabilities, the question whether the design of drainage system could be prepared with abnormal rainfall condition or not has been on the rise. Usually, the drainage system has been designed by rainfall I-D-F (Intensity-Duration-Frequency) curve with assumption that I-D-F curve is stationary. The design approach of the drainage system has limitation not to consider the extreme rainfall condition of which I-D-F curve is non-stationary by climate change and variabilities. Therefore, the assumption that the I-D-F curve is stationary to design drainage system maybe not available in the climate change period, because climate change has changed the characteristics of extremes rainfall event to be non-stationary. In this paper, design rainfall by rainfall duration and non-stationary I-D-F curve are derived by the conditional GEV distribution considering non-stationary of rainfall characteristics. Furthermore, the effect of designed peak flow with increase of rainfall intensity was analyzed by distributed rainfall-runoff model, S-RAT(Spatial Runoff Assessment Tool). Although there are some difference by rainfall duration, the traditional I-D-F curves underestimates the extreme rainfall events for high-frequency rainfall condition. As a result, this paper suggest that traditional I-D-F curves could not be suitable for the design of drainage system under climate change condition. Keywords : Drainage system, Climate Change, non-stationary, I-D-F curves This research was supported by a grant 'Development of multi-function debris flow control technique considering extreme rainfall event' [NEMA-Natural-2014-74] from the Natural Hazard Mitigation Research Group, National Emergency Management Agency of KOREA

[Lung abscess: changes in treatment?].

PubMed

Clottu, E; Nicod, L P

2015-11-18

Lung abscess occurs in very pleomorphic according to germs initially involved. The mechanism commonly found is an aspiration of the oropharyngeal flora in patients with disorders of consciousness or swallowing. The infection is polymicrobial, with presence of anaerobic germs in 2/3 of the cases. The support consists of a prolonged antibiotic treatment, as well as anaerobic until resolution or stability of the radiological image. In case of prolonged toxic state, drainage of the abscess is to be discussed especially if there is no airways drainage. Surgical sanctions is rarely needed regardless of the size of the abscess, unless underlying carcinoma is present.

Shallow Ground-Water Flux Beneath a Restored Wetland Using Two-Dimensional Simulation of Ground-Water Flow and Heat Transport

NASA Astrophysics Data System (ADS)

Burow, K. R.; Gamble, J. M.; Fujii, R.; Constantz, J.

2001-12-01

Water flowing through the Sacramento-San Joaquin River Delta supplies drinking water to more than 20 million people in California. Delta water contains elevated concentrations of dissolved organic carbon (DOC) from drainage through the delta peat soils, forming trihalomethanes when the water is chlorinated for drinking. Land subsidence caused by oxidation of the peat soils has led to increased pumping of drainage water from delta islands to maintain arable land. An agricultural field on Twitchell Island was flooded in 1997 to evaluate continuous flooding as a technique to mitigate subsidence. The effects of shallow flooding on DOC loads to the drain water must be determined to evaluate the feasibility of this technique. In this study, heat is used as a nonconservative tracer to determine shallow ground-water flux and calculate DOC loads to an adjacent drainage ditch. Temperature profiles and water levels were measured in 12 wells installed beneath the pond, in the pond, and in an adjacent drainage ditch from May 2000 to June 2001. The range in seasonal temperatures decreased with depth, but seasonal temperature variation was evident in wells screened as deep as 10 to 12 feet below land surface. A constant temperature of 17 degrees C was measured in wells 25 feet beneath the pond. Ground-water flux beneath the pond was quantified in a two-dimensional simulation of water and heat exchange using the SUTRA flow and transport model. The effective vertical hydraulic conductivity of the peat soils underlying the pond was estimated through model calibration. Calibrated hydraulic conductivity is higher (1E-5 m/sec) than estimates from slug tests (2E-6 m/sec). Modeled pond seepage is similar to that estimated from a water budget, although the total seepage determined from the water budget is within the range of error of the instrumentation. Overall, model results indicate that recharge from the pond flows along shallow flow paths and that travel times through the peat to the drainage ditch may be on the order of decades.

Co-development of climate smart flooded rice farming systems

NASA Astrophysics Data System (ADS)

de Neergaard, Andreas; Stoumann Jensen, Lars; Ly, Proyuth; Pandey, Arjun; Duong Vu, Quynh; Tariq, Azeem; Islam, Syed; van Groenigen, Jan Willem; Sander, Bjoern Ole; de Tourdonnet, Stephane; Van Mai, Trinh; Wassmann, Reiner

2017-04-01

Mid-season drainage in flooded rice is known to reduce CH4 emission, while effects on N2O emission are more variable. Banning of crop-residue burning, and growing markets for organically fertilized rice, are resulting in systems with larger reactive C input, and potentially larger methane emissions. Tight farming systems with 2 or 3 annual crops are effective in mitigating emissions, in that the land sparing value is high, but put serious constraints on mitigation options under increased C input scenarios. In a series of field (Cambodia, Philippines and Vietnam) and greenhouse experiments, we investigated the effect of a variety of organic amendments and wetting and drying cycles on yield and GHG emissions. Specifically we have tested the effect of inserting very early, or even-pre-planting drainage, as a means to accelerate turnover of straw or other C sources, and reduce methane emission later in the season. Overall, our results showed that drying periods had minimal impact on yields, while reducing overall GHG emission. Methane emission was strongly controlled by C availability in the substrate (on equal total C-input basis), increasing in the order: biochar-composts-animal manure-fresh material. Nitrous oxide emissions generally increased with draining cycles, but did not lead to overall increase in GHG emissions as its contribution was balanced by lowered CH4 emissions. Growth chamber experiments showed that methane emission was significantly reduced for extended periods after re-flooding, hence the idea of early drainage was developed. Meanwhile, Cambodian farmers expressed concerns over re-supply of water after drainage. In response to that, we tested if early-season drainage could replace mid-season drainage. With addition of labile carbon substrates (straw) duration of early season drainage was more important for reducing GHG emissions, than duration of mid-season drainage, and had the highest potential for total emission reduction. In a farmers-field trial in Vietnam, pre-planting and early season drainage was tested in spring and summer rice, under individual and community water management regimes, and at 2 straw application levels. Pre-season drainage was difficult for farmers to implement, due to the short duration of fallow between cropping seasons. Early season drainage was most effective in lowering methane emissions at both straw application levels. Unsurprisingly, the well-managed drainage control (community system) was significantly more effective in mitigating emissions, than the individually water management. Surveys among farming communities in Philippines, subject to agricultural campaigns on alternate-wetting-and-drying showed higher adoption among farmers who actively pumped water to their fields, compared to gravity-fed water supply, due to the direct savings experienced by farmers pumping water. Several other factors positively influenced adoption of mitigation techniques, including education level, access to extension services, wealth and farm size, and age of farmer (negatively correlated to adoption rate). In conclusion, drainage periods are even more important to mitigate emissions when including organic manures or residues in flooded rice, and early-season drainage should be further explored as a more safe and convenient option for smallholders. Participatory development of climate smart prototypes will be essential, and a model for such is presented.

Surgical management of the left superior vena cava draining into the left atrium: a novel off-pump technique using the left atrial appendage

PubMed Central

Boutayeb, Alaae; Marmade, Lahcen; Bensouda, Adil; Moughil, Said

2012-01-01

The left superior vena cava is the most common congenital venous anomaly in the chest; however, its drainage into the left atrium is exceptional. The aim of the paper is to describe our novel technique to connect the left superior vena cava to the right cavities using the left atrial appendage, without cardiopulmonary bypass. PMID:22802356

Endocanalicular diode laser dacryocystorhinostomy for nasolacrimal duct obstruction: short-term results of a new minimally invasive surgical technique.

PubMed

Özçimen, Muammer; Uysal, Ismail Onder; Eryılmaz, Mehmet Akif; Kal, Ali

2010-11-01

To evaluate the results, complications, effectiveness, and operative results of the endocanalicular laser dacryocystorhinostomy (ECL DCR) in the distal obstructions of the lacrimal drainage system. Sixty eyes of 57 patients who had a diagnosis of distal obstruction of the lacrimal drainage system were evaluated retrospectively in this study. All patients underwent ECL DCR by diode laser between October 2008 and July 2009. Forty-nine patients (86%) were females, 8 patients (14%) were males, and age distribution was between 3 and 84 years old (median, 40 y). The canaliculi were intubated by a silicone tube. The patency of the nasolacrimal system was controlled by lacrimal lavage, loss of epiphora, and endoscopic evaluation of the endonasal rhinostomy site with routine follow-up scheduled at first day and 1-week, 1-month, and 3-month postoperative intervals. After the 60 ECL DCRs, 10 patients underwent revision ECL DCR because of the persistent epiphora. The patency of the nasolacrimal duct or the decrease of the symptoms was assigned as success. There were no symptoms at all in 83.3% of the patients. The ECL DCR in the treatment of the distal obstructions of the lacrimal drainage system was easily tolerated by the patients, cosmetically preferred because there was no incision and scar formation with high success rates, and a minimally invasive alternative technique.

Systemic venous drainage: can we help Newton?

PubMed

Corno, Antonio F

2007-06-01

In recent years substantial progress occurred in the techniques of cardiopulmonary bypass, but the factor potentially limiting the flexibility of cardiopulmonary bypass remains the drainage of the systemic venous return. In the daily clinical practice of cardiac surgery, the amount of systemic venous return on cardiopulmonary bypass is directly correlated with the amount of the pump flow. As a consequence, the pump flow is limited by the amount of venous return that the pump is receiving. On cardiopulmonary bypass the amount of venous drainage depends upon the central venous pressure, the height differential between patient and inlet of the venous line into the venous reservoir, and the resistance in the venous cannula(s) and circuit. The factors determining the venous return to be taken into consideration in cardiac surgery are the following: (a) characteristics of the individual patient; (b) type of planned surgical procedure; (c) type of venous cannula(s); (d) type of circuit for cardiopulmonary bypass; (e) strategy of cardiopulmonary bypass; (f) use of accessory mechanical systems to increased the systemic venous return. The careful pre-operative evaluation of all the elements affecting the systemic venous drainage, including the characteristics of the individual patient and the type of required surgical procedure, the choice of the best strategy of cardiopulmonary bypass, and the use of the most advanced materials and tools, can provide a systemic venous drainage substantially better than what it would be allowed by the simple "Law of universal gravitation" by Isaac Newton.

Management and prevention of chylous leakage after laparoscopic lymphadenectomy.

PubMed

Han, L-P; Zhang, H-M; Abha, H-D; Liu, T; Zhang, X-P

2014-01-01

To investigate the development and management of chylous leakage after laparoscopic retroperitoneal lymphadenectomy. From July 2006 to September 2013, 13 cases of chylous leakage after the laparoscopic lymphadenectomy (6 cases of renal cell carcinoma, 4 cases of gastric cancer, 2 cases of ovarian cancer, 1 case of endometrial cancer) were studied to analyze the occurrence, development and management of chylous leakage. In 3 cases (2 cases of renal cell carcinoma, 1 case of gastric cancer) massive amount of milky fluid drainage was be seen after the first two days post operation. Dietary intervention, TPN (total parenteral nutrition), somatostatin therapy, maintenance of continuous drainage helped to successfully manage the condition in about 1 month duration. In the remaining 10 cases, chylous leakage appeared after restoring normal diet. Managed with changes in diet and maintenance of unobstructed drainage, they were cured in about 2 weeks after treatment. There was significant reduction in drain output, ultrasonography did not reveal presence of free fluid collection in abdomen, and the patients were in good condition without signs and symptoms of infections. Chylous leakage is a rare complication of retroperitoneal lymph node dissection. Surgeons should be familiar with laparoscopic techniques, relevant anatomy and be aware of the fact that the effect of CO2 pressure and use of ultrasonic knife to occlude the lymphatic vessel can transiently block the leakage making the surgeon overlook them. Routine placement of indwelling drainage tube, immediate diagnosis, dietary modification, TPN, somatostatin and drainage are the modalities of conservative management.

An assessment on the use of bivariate, multivariate and soft computing techniques for collapse susceptibility in GIS environ

NASA Astrophysics Data System (ADS)

Yilmaz, Işik; Marschalko, Marian; Bednarik, Martin

2013-04-01

The paper presented herein compares and discusses the use of bivariate, multivariate and soft computing techniques for collapse susceptibility modelling. Conditional probability (CP), logistic regression (LR) and artificial neural networks (ANN) models representing the bivariate, multivariate and soft computing techniques were used in GIS based collapse susceptibility mapping in an area from Sivas basin (Turkey). Collapse-related factors, directly or indirectly related to the causes of collapse occurrence, such as distance from faults, slope angle and aspect, topographical elevation, distance from drainage, topographic wetness index (TWI), stream power index (SPI), Normalized Difference Vegetation Index (NDVI) by means of vegetation cover, distance from roads and settlements were used in the collapse susceptibility analyses. In the last stage of the analyses, collapse susceptibility maps were produced from the models, and they were then compared by means of their validations. However, Area Under Curve (AUC) values obtained from all three models showed that the map obtained from soft computing (ANN) model looks like more accurate than the other models, accuracies of all three models can be evaluated relatively similar. The results also showed that the conditional probability is an essential method in preparation of collapse susceptibility map and highly compatible with GIS operating features.

Techniques for estimating 7-day, 10-year low-flow characteristics for ungaged sites on streams in Mississippi

USGS Publications Warehouse

Telis, Pamela A.

1992-01-01

Mississippi State water laws require that the 7-day, 10-year low-flow characteristic (7Q10) of streams be used as a criterion for issuing wastedischarge permits to dischargers to streams and for limiting withdrawals of water from streams. This report presents techniques for estimating the 7Q10 for ungaged sites on streams in Mississippi based on the availability of baseflow discharge measurements at the site, location of nearby gaged sites on the same stream, and drainage area of the ungaged site. These techniques may be used to estimate the 7Q10 at sites on natural, unregulated or partially regulated, and non-tidal streams. Low-flow characteristics for streams in the Mississippi River alluvial plain were not estimated because the annual lowflow data exhibit decreasing trends with time. Also presented are estimates of the 7Q10 for 493 gaged sites on Mississippi streams.Techniques for estimating the 7Q10 have been developed for ungaged sites with base-flow discharge measurements, for ungaged sites on gaged streams, and for ungaged sites on ungaged streams. For an ungaged site with one or more base-flow discharge measurements, base-flow discharge data at the ungaged site are related to concurrent discharge data at a nearby gaged site. For ungaged sites on gaged streams, several methods of transferring the 7Q10 from a gaged site to an ungaged site were developed; the resulting 7Q10 values are based on drainage area prorations for the sites. For ungaged sites on ungaged streams, the 7Q10 is estimated from a map developed for. this study that shows the unit 7Q10 (7Q10 per square mile of drainage area) for ungaged basins in the State. The mapped values were estimated from the unit 7Q10 determined for nearby gaged basins, adjusted on the basis of the geology and topography of the ungaged basins.

Piggyback transplantation with side-to-side cavocavostomy is an ideal technique for right split liver allograft implantation.

PubMed

Lerut, J; de Ville de Goyet, J; Donataccio, M; Reding, R; Otte, J B

1994-11-01

Split liver grafting has not gained wide acceptance mainly because of different vascular and biliary technical problems. A new technique of right split liver transplantation is described. The piggyback implantation technique, using wide side-to-side cavocavostomy overcomes problems encountered when sharing the superhepatic vena cava cuff between two livers and obtains optimal drainage of venous allograft outflow, thus avoiding extensive bleeding at the transection margin. This technique was successfully used in two adult recipients. Piggyback transplantation using wide side-to-side cavocavostomy allows easy and safe implantation of the right split liver allograft.

An evaluation and comparison of intraventricular, intraparenchymal, and fluid-coupled techniques for intracranial pressure monitoring in patients with severe traumatic brain injury.

PubMed

Vender, John; Waller, Jennifer; Dhandapani, Krishnan; McDonnell, Dennis

2011-08-01

Intracranial pressure measurements have become one of the mainstays of traumatic brain injury management. Various technologies exist to monitor intracranial pressure from a variety of locations. Transducers are usually placed to assess pressure in the brain parenchyma and the intra-ventricular fluid, which are the two most widely accepted compartmental monitoring sites. The individual reliability and inter-reliability of these devices with and without cerebrospinal fluid diversion is not clear. The predictive capability of monitors in both of these sites to local, regional, and global changes also needs further clarification. The technique of monitoring intraventricular pressure with a fluid-coupled transducer system is also reviewed. There has been little investigation into the relationship among pressure measurements obtained from these two sources using these three techniques. Eleven consecutive patients with severe, closed traumatic brain injury not requiring intracranial mass lesion evacuation were admitted into this prospective study. Each patient underwent placement of a parenchymal and intraventricular pressure monitor. The ventricular catheter tubing was also connected to a sensor for fluid-coupled measurement. Pressure from all three sources was measured hourly with and without ventricular drainage. Statistically significant correlation within each monitoring site was seen. No monitoring location was more predictive of global pressure changes or more responsive to pressure changes related to patient stimulation. However, the intraventricular pressure measurements were not reliable in the presence of cerebrospinal fluid drainage whereas the parenchymal measurements remained unaffected. Intraparenchymal pressure monitoring provides equivalent, statistically similar pressure measurements when compared to intraventricular monitors in all care and clinical settings. This is particularly valuable when uninterrupted cerebrospinal fluid drainage is desirable.

Potential advantage of studying the lymphatic drainage by sentinel node technique and SPECT-CT image fusion for pelvic irradiation of prostate cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Krengli, Marco; Ballare, Andrea; Cannillo, Barbara

2006-11-15

Purpose: This study aims to investigate the in vivo drainage of lymphatic spread by using the sentinel node (SN) technique and single-photon emission computed tomography (SPECT)-computed tomography (CT) image fusion, and to analyze the impact of such information on conformal pelvic irradiation. Methods and Materials: Twenty-three prostate cancer patients, candidates for radical prostatectomy already included in a trial studying the SN technique, were enrolled. CT and SPECT images were obtained after intraprostate injection of 115 MBq of {sup 99m}Tc-nanocolloid, allowing identification of SN and other pelvic lymph nodes. Target and nontarget structures, including lymph nodes identified by SPECT, were drawnmore » on SPECT-CT fusion images. A three-dimensional conformal treatment plan was performed for each patient. Results: Single-photon emission computed tomography lymph nodal uptake was detected in 20 of 23 cases (87%). The SN was inside the pelvic clinical target volume (CTV{sub 2}) in 16 of 20 cases (80%) and received no less than the prescribed dose in 17 of 20 cases (85%). The most frequent locations of SN outside the CTV{sub 2} were the common iliac and presacral lymph nodes. Sixteen of the 32 other lymph nodes (50%) identified by SPECT were found outside the CTV{sub 2}. Overall, the SN and other intrapelvic lymph nodes identified by SPECT were not included in the CTV{sub 2} in 5 of 20 (25%) patients. Conclusions: The study of lymphatic drainage can contribute to a better knowledge of the in vivo potential pattern of lymph node metastasis in prostate cancer and can lead to a modification of treatment volume with consequent optimization of pelvic irradiation.« less

Hydrological problems of water resources in irrigated agriculture: A management perspective

NASA Astrophysics Data System (ADS)

Singh, Ajay

2016-10-01

The development of irrigated agriculture is necessary for fulfilling the rising food requirements of the burgeoning global population. However, the intensification of irrigated agriculture causes the twin menace of waterlogging and soil salinization in arid and semiarid regions where more than 75% of the world's population lives. These problems can be managed by either adopting preventive measures which decrease the inflow of water and salt or by employing remedial measures which increase the outflow. This paper presents an overview of various measures used for the management of waterlogging and salinity problems. The background, processes involved, and severity of waterlogging and salinity problems are provided. The role of drainage systems, conjunctive use of different water sources, use of computer-based mathematical models, and the use of remote sensing and GIS techniques in managing the problems are discussed. Conclusions are provided which could be useful for all the stakeholders.

Censored rainfall modelling for estimation of fine-scale extremes

NASA Astrophysics Data System (ADS)

Cross, David; Onof, Christian; Winter, Hugo; Bernardara, Pietro

2018-01-01

Reliable estimation of rainfall extremes is essential for drainage system design, flood mitigation, and risk quantification. However, traditional techniques lack physical realism and extrapolation can be highly uncertain. In this study, we improve the physical basis for short-duration extreme rainfall estimation by simulating the heavy portion of the rainfall record mechanistically using the Bartlett-Lewis rectangular pulse (BLRP) model. Mechanistic rainfall models have had a tendency to underestimate rainfall extremes at fine temporal scales. Despite this, the simple process representation of rectangular pulse models is appealing in the context of extreme rainfall estimation because it emulates the known phenomenology of rainfall generation. A censored approach to Bartlett-Lewis model calibration is proposed and performed for single-site rainfall from two gauges in the UK and Germany. Extreme rainfall estimation is performed for each gauge at the 5, 15, and 60 min resolutions, and considerations for censor selection discussed.

Innovative approaches to glaucoma management of Boston keratoprosthesis type 1.

PubMed

Vajaranant, Thasarat S; Liu, Jessica; Wilensky, Jacob; Cortina, M Soledad; Aref, Ahmad A

2016-09-01

Glaucoma remains a prevalent disorder and visual limiting factor after Boston keratoprosthesis type 1 implantation. Patients with glaucoma have worse initial and late visual acuity outcomes after otherwise successful keratoprosthesis implantation. Management of glaucoma in the setting of a keratoprosthesis is challenging because of relatively rapid progression and an inability to accurately measure intraocular pressure (IOP). In addition, there are no standard guidelines for glaucoma surveillance and monitoring after keratoprosthesis surgery. This report provides a review of the current literature and offers innovative strategies that will overcome the challenges in managing glaucoma in the setting of a Boston keratoprosthesis type 1 implant. The topics that will be discussed in this section include alternative methods for IOP measurement, rationales and surgical techniques for a pars plana tube placement for glaucoma drainage device, effective medical and laser treatment, the risk for IOP elevations after YAG laser, and practical guides to glaucoma surveillance and monitoring.

Separation of man-made and natural patterns in high-altitude imagery of agricultural areas

NASA Technical Reports Server (NTRS)

Samulon, A. S.

1975-01-01

A nonstationary linear digital filter is designed and implemented which extracts the natural features from high-altitude imagery of agricultural areas. Essentially, from an original image a new image is created which displays information related to soil properties, drainage patterns, crop disease, and other natural phenomena, and contains no information about crop type or row spacing. A model is developed to express the recorded brightness in a narrow-band image in terms of man-made and natural contributions and which describes statistically the spatial properties of each. The form of the minimum mean-square error linear filter for estimation of the natural component of the scene is derived and a suboptimal filter is implemented. Nonstationarity of the two-dimensional random processes contained in the model requires a unique technique for deriving the optimum filter. Finally, the filter depends on knowledge of field boundaries. An algorithm for boundary location is proposed, discussed, and implemented.

Genetic variation in westslope cutthroat trout Oncorhynchus clarkii lewisi: Implications for conservation

USGS Publications Warehouse

Drinan, D.P.; Kalinowski, S.T.; Vu, N.V.; Shepard, B.B.; Muhlfeld, C.C.; Campbell, M.R.

2011-01-01

Twenty-five populations of westslope cutthroat trout from throughout their native range were genotyped at 20 microsatellite loci to describe the genetic structure of westslope cutthroat trout. The most genetic diversity (heterozygosity, allelic richness, and private alleles) existed in populations from the Snake River drainage, while populations from the Missouri River drainage had the least. Neighbor-joining trees grouped populations according to major river drainages. A great amount of genetic differentiation was present among and within all drainages. Based on Nei's DS, populations in the Snake River were the most differentiated, while populations in the Missouri River were the least. This pattern of differentiation is consistent with a history of sequential founding events through which westslope cutthroat trout may have experienced a genetic bottleneck as they colonized each river basin from the Snake to the Clark Fork to the Missouri river. These data should serve as a starting point for a discussion on management units and possible distinct population segments. Given the current threats to the persistence of westslope cutthroat trout, and the substantial genetic differentiation between populations, these topics warrant attention. ?? 2011 Springer Science+Business Media B.V.

FISH ASSEMBLAGE GROUPS IN THE UPPER TENNESSEE RIVER BASIN

EPA Science Inventory

A hierarchical clustering technique was used to classify sites in the upper Tennessee River basin based on relative abundance of fish species. Five site groups were identified. These groups differed mainly by the occurrence of minnow and darter species. Drainage area and ecore...

The use of the venous stripper for graft removal in arterial reoperations.

PubMed

Shifrin, E G; Eid, A; Anner, H; Witz, M

1987-10-01

A simple technique for removal of synthetic grafts using a standard venous stripper inside the graft is described. The method permits the simultaneous placement of a drainage tube in the canal after graft removal in cases where the graft is infected.

Interface fluctuations during rapid drainage

NASA Astrophysics Data System (ADS)

Ayaz, Monem; Toussaint, Renaud; Schäfer, Gerhard; Jørgen Måløy, Knut; Moura, Marcel

2017-04-01

We experimentally study the interface dynamics of an immiscible fluid as it invades a monolayer of saturated porous medium through rapid drainage. The seemingly stable and continuous motion of the interface at macroscale, involves numerous abrupt pore-scale jumps and local reconfigurations of the interface. By computing the velocity fluctuations along the invasion front from sequences of images captured at high frame rate, we are able to study both the local and global behavior. The latter displays an intermittent behavior with power-law distributed avalanches in size and duration. As the system is drained potential surface energy is stored at the interface up to a given threshold in pressure. The energy released generates elastic waves at the confining plate, which we detect using piezoelectric type acoustic sensors. By detecting pore-scale events emanating from the depinning of the interface, we look to develop techniques for localizing the displacement front. To assess the quality of these techniques, optical monitoring is done in parallel using a high speed camera.

Application of standard photogeologic techniques to LANDSAT imagery for mineral exploration in the basin and range province of Utah and Nevada

NASA Technical Reports Server (NTRS)

Lattman, L. H. (Principal Investigator)

1977-01-01

The author has identified the following significant results. Standard photogeologic techniques were applied to LANDSAT imagery of the basin and range province of Utah and Nevada to relate linear, tonal, textural, drainage, and geomorphic features to known mineralized areas in an attempt to develop criteria for the location of mineral deposits. No consistent correlation was found between lineaments, mapped according to specified criteria, and locations of mines, mining districts, or intrusive outcrops. Tonal and textural patterns were more closely related to geologic outcrop patterns than to mineralization. A statistical study of drainage azimuths of various length classes as measured on LANDSAT showed significant correlation with mineralized districts in the length class of 3-6 km. Alignments of outcrops of basalt, a rock type highly visible on LANDSAT imagery, appear to be colinear with acidic and intermediate intrusive centers in some areas and may assist on the recognition of regional fracture systems for mineral exploration.

Reevaluating the need for routine drainage in reduction mammaplasty.

PubMed

Matarasso, A; Wallach, S G; Rankin, M

1998-11-01

The incidence of complications after reduction mammaplasty without drains was reviewed by analysis of 50 bilateral reduction mammaplasty procedures. Patients ranged in age from 14 to 65 years; the average combined volume removed was 953 g. Eighty-four percent of the patients underwent a Pitanguy technique, and the remaining patients underwent an inferior pedicle or amputative technique with free nipple grafts. Three patients had six complications; one of these patients had three of the complications. Complications included two cases of fat necrosis and one case of wound disruption. One patient had a hematoma with wound disruption and partial nipple loss. There were no cases of infection. The purpose of this study was to determine the rate of complications in reduction mammaplasty performed without drains. Incidentally, statistical analysis using the chi-squared test revealed that this series without drains compared favorably with previously published data for reduction mammaplasty using drains. It is concluded that routine closed suction drainage after reduction mammaplasty is unnecessary and should be reconsidered.

Fishes of the Blackwater River Drainage, Tucker County, West Virginia

USGS Publications Warehouse

Cincotta, Daniel A.; Welsh, Stuart A.; Wegman, Douglas P.; Oldham, Thomas E.; Hedrick, Lara B.

2015-01-01

The Blackwater River, a tributary of the upper Cheat River of the Monongahela River, hosts a modest fish fauna. This relatively low diversity of fish species is partly explained by its drainage history. The Blackwater was once part of the prehistoric, northeasterly flowing St. Lawrence River. During the Pleistocene Epoch, the fauna was significantly affected by glacial advance and by proglacial lakes and their associated overflows. After the last glacial retreat, overflow channels, deposits, and scouring altered drainage courses and connected some of the tributaries of the ancient Teays and Pittsburgh drainages. These major alterations allowed the invasion of fishes from North America's more species-rich southern waters. Here we review fish distributions based on 67 surveys at 34 sites within the Blackwater River drainage, and discuss the origin and status of 37 species. Within the Blackwater River watershed, 30 species (20 native, 10 introduced) have been reported from upstream of Blackwater Falls, whereas 29 (26 native, 3 introduced) have been documented below the Falls. Acid mine drainage, historic lumbering, and human encroachment have impacted the Blackwater's ichthyofauna. The fishes that have been most affected are Salvelinus fontinalis (Brook Trout), Clinostomus elongatus (Redside Dace), Nocomis micropogon (River Chub), Hypentelium nigricans (Northern Hog Sucker), Etheostoma flabellare (Fantail Darter), and Percina maculata(Blackside Darter). The first two species incurred range reductions, whereas the latter four were probably extirpated. In the 1990s, acid remediation dramatically improved the water quality of the river below Davis. Recent surveys in the lower drainage revealed 15 fishes where none had been observed since at least the 1940s; seven of these (Cyprinella spiloptera [Spotfin Shiner], Luxilus chrysocephalus [Striped Shiner], Notropis photogenis [Silver Shiner], N. rubellus [Rosyface Shiner];Micropterus dolomieu [Smallmouth Bass]; and Etheostoma camurum [Bluebreast Darter] and E. variatum [Variegate Darter]) represent additions to the faunal list of the Blackwater River.

Emergent spectral properties of river network topology: an optimal channel network approach.

PubMed

Abed-Elmdoust, Armaghan; Singh, Arvind; Yang, Zong-Liang

2017-09-13

Characterization of river drainage networks has been a subject of research for many years. However, most previous studies have been limited to quantities which are loosely connected to the topological properties of these networks. In this work, through a graph-theoretic formulation of drainage river networks, we investigate the eigenvalue spectra of their adjacency matrix. First, we introduce a graph theory model for river networks and explore the properties of the network through its adjacency matrix. Next, we show that the eigenvalue spectra of such complex networks follow distinct patterns and exhibit striking features including a spectral gap in which no eigenvalue exists as well as a finite number of zero eigenvalues. We show that such spectral features are closely related to the branching topology of the associated river networks. In this regard, we find an empirical relation for the spectral gap and nullity in terms of the energy dissipation exponent of the drainage networks. In addition, the eigenvalue distribution is found to follow a finite-width probability density function with certain skewness which is related to the drainage pattern. Our results are based on optimal channel network simulations and validated through examples obtained from physical experiments on landscape evolution. These results suggest the potential of the spectral graph techniques in characterizing and modeling river networks.

The use of deconvolution techniques to identify the fundamental mixing characteristics of urban drainage structures.

PubMed

Stovin, V R; Guymer, I; Chappell, M J; Hattersley, J G

2010-01-01

Mixing and dispersion processes affect the timing and concentration of contaminants transported within urban drainage systems. Hence, methods of characterising the mixing effects of specific hydraulic structures are of interest to drainage network modellers. Previous research, focusing on surcharged manholes, utilised the first-order Advection-Dispersion Equation (ADE) and Aggregated Dead Zone (ADZ) models to characterise dispersion. However, although systematic variations in travel time as a function of discharge and surcharge depth have been identified, the first order ADE and ADZ models do not provide particularly good fits to observed manhole data, which means that the derived parameter values are not independent of the upstream temporal concentration profile. An alternative, more robust, approach utilises the system's Cumulative Residence Time Distribution (CRTD), and the solute transport characteristics of a surcharged manhole have been shown to be characterised by just two dimensionless CRTDs, one for pre- and the other for post-threshold surcharge depths. Although CRTDs corresponding to instantaneous upstream injections can easily be generated using Computational Fluid Dynamics (CFD) models, the identification of CRTD characteristics from non-instantaneous and noisy laboratory data sets has been hampered by practical difficulties. This paper shows how a deconvolution approach derived from systems theory may be applied to identify the CRTDs associated with urban drainage structures.

Demonstration to characterize watershed runoff potential by microwave techniques

NASA Technical Reports Server (NTRS)

Blanchard, B. J.

1977-01-01

Characteristics such as storage capacity of the soil, volume of storage in vegetative matter, and volume of storage available in local depressions are expressed in empirical watershed runoff equations as one or more coefficients. Conventional techniques for estimating coefficients representing the spatial distribution of these characteristics over a watershed drainage area are subjective and produce significant errors. Characteristics of the wear surface are described as a single coefficient called the curve number.

Technique for estimating depth of 100-year floods in Tennessee

USGS Publications Warehouse

Gamble, Charles R.; Lewis, James G.

1977-01-01

Preface: A method is presented for estimating the depth of the loo-year flood in four hydrologic areas in Tennessee. Depths at 151 gaging stations on streams that were not significantly affected by man made changes were related to basin characteristics by multiple regression techniques. Equations derived from the analysis can be used to estimate the depth of the loo-year flood if the size of the drainage basin is known.

Preliminary evaluation of a constructed wetland for treating extremely alkaline (pH 12) steel slag drainage.

PubMed

Mayes, W M; Aumônier, J; Jarvis, A P

2009-01-01

High pH (> 12) leachates are an environmental problem associated with drainage from lime (CaO)-rich industrial residues such as steel slags, lime spoil and coal combustion residues. Recent research has highlighted the potential for natural ('volunteer') wetlands to buffer extremely alkaline influent waters. This appears ascribable to high CO(2) partial pressures in the wetland waters from microbial respiration, which accelerates precipitation of calcium carbonate (CaCO(3)), and the high specific surface area for mineral precipitation offered by macrophytes. The research presented here builds on this and provides preliminary evaluation of a constructed wetland built in March 2008 to buffer drainage from steel slag heaps in north-east England. The drainage water from the slag mounds is characterised by a mean pH of 11.9, high concentrations of Ca (up to 700 mg/L), total alkalinity (up to 800 mg/L as CaCO(3)) and are slightly brackish (Na = 300 mg/L; Cl = 400 mg/L) reflecting native groundwaters at this coastal setting. Documented calcite precipitation rates (mean of 5 g CaCO(3)/m(2)/day) from nearby volunteer sites receiving steel slag drainage were used to scale the constructed wetland planted with Phragmites australis; a species found to spontaneously grow in the vicinity of the discharge. Improved performance of the wetland during summer months may at least in part be due to biological activity which enhances rates of calcite precipitation and thus lowering of pH. Secondary Ca-rich precipitates also serve as a sink for some trace elements present at low concentrations in the slag leachate such as Ni and V. The implications for scaling and applying constructed wetlands for highly alkaline drainage are discussed.

Assessment of Nitrate-N Load in Subsurface Drainage Water from the Agricultural Fields in the Fergana Valley, Uzbekistan

NASA Astrophysics Data System (ADS)

Kenjabaev, S.; Forkutsa, I.; Dukhovny, V.; Frede, H. G.

2012-04-01

Leaching of nitrate-N (NO3-) from irrigated agricultural land and water contamination have become a worldwide concern. This study was conducted to investigate amount of nitrate-N leached to groundwater and surface water from irrigated cotton, winter wheat and maize fields in the Fergana Valley (Uzbekistan). Therefore at two sites ("Akbarabad" and "Azizbek") equipped with closed horizontal drainage system during 2010-2011 vegetation seasons we monitored water flow, nutrient concentrations and salinity at surface and subsurface drains, at irrigation canals and groundwater. We also applied stable isotopes (δ2H and δ18O) method in order to investigate the source of drainage water runoff. Discussed are results of 2010. Farmers fertilized cotton fields with ammonium nitrate of 350-450 kg ha-1 in "Akbarabad" and 700 kg ha-1 in "Azizbek" sites. In winter wheat and maize fields (in "Akbarabad") about 500 kg ha-1 of ammonium nitrate were applied. Cotton fields were irrigated with 2700 m3 ha-1 ("Akbarabad") and 3500 m3 ha-1 ("Azizbek"). In winter wheat and maize fields applied irrigation water amounted to 3900 m3 ha-1 and 723 m3 ha-1, respectively. Frequent groundwater and subsurface drainage water sampling revealed that nitrate leaching occurred mostly during and right after the irrigation events. The estimated average nitrate-N concentration in subsurface drainage water in "Akbarabad" was slightly higher (9 mg l-1) than in "Azizbek" (8 mg l-1). During July-November (2010), in average, nitrate-N losses through subsurface drainage amounted to 24 kg ha-1 in "Akbarabad" and 18 kg ha-1 in "Azizbek". The salinity of drainage water at both sites was similar and varied between 2.3-2.7 dS m-1. Preliminary results of isotope signals of studied water (precipitation, drainage, irrigation and ground water) indicate that the source of drainage water runoff comes from the irrigation water, while the contribution of rainfall is negligible. It is planned to run simulations with DRAINMOD model for further investigation of water and N balances of the selected sites. Developed recommendations for farmers on optimum irrigation water amounts and N fertilization will allow reducing environmental risks in agricultural lands of the Fergana Valley.

Flare-ups in endodontics: II. Therapeutic measures. 1985.

PubMed

Seltzer, Samuel; Naidorf, Irving J

2004-07-01

Various treatment regimens for the relief of pain during endodontic therapy, including relief of occlusion, pre-medication, establishment of drainage, and intracanal and systemic medications are presented. In addition, the rationale for the use of placebos is discussed.

Cholesterol granuloma of the petrous apex: establishment of a drainage route into the superior tympanic cavity--technical note.

PubMed

Kamiguchi, H; Kawase, T; Toya, S; Inoue, Y

1996-09-01

A 40-year-old male presented with a cholesterol granuloma of the petrous apex manifesting as progressive hearing loss and tinnitus. The lesion was treated via an extradural middle cranial fossa approach employing a new procedure to establish a drainage pathway into the superior tympanic cavity which preserved his hearing. The pathway was formed by a groove 5 mm wide and deep in the anterolateral aspect of the petrous bone, crossing the major petrosal nerve and carotid artery, running around the cochlea, crossing the tensor tympanic muscle, and entering the superior tympanic cavity above the orifice of the eustachian tube. This procedure is easy to perform without special techniques.

DEVELOPMENT AND OPTIMIZATION OF GAS-ASSISTED GRAVITY DRAINAGE (GAGD) PROCESS FOR IMPROVED LIGHT OIL RECOVERY

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dandina N. Rao; Subhash C. Ayirala; Madhav M. Kulkarni

This report describes the progress of the project ''Development and Optimization of Gas-Assisted Gravity Drainage (GAGD) Process for Improved Light Oil Recovery'' for the duration of the second project year (October 1, 2003--September 30, 2004). There are three main tasks in this research project. Task 1 is scaled physical model study of GAGD process. Task 2 is further development of vanishing interfacial tension (VIT) technique for miscibility determination. Task 3 is determination of multiphase displacement characteristics in reservoir rocks. In Section I, preliminary design of the scaled physical model using the dimensional similarity approach has been presented. Scaled experiments onmore » the current physical model have been designed to investigate the effect of Bond and capillary numbers on GAGD oil recovery. Experimental plan to study the effect of spreading coefficient and reservoir heterogeneity has been presented. Results from the GAGD experiments to study the effect of operating mode, Bond number and capillary number on GAGD oil recovery have been reported. These experiments suggest that the type of the gas does not affect the performance of GAGD in immiscible mode. The cumulative oil recovery has been observed to vary exponentially with Bond and capillary numbers, for the experiments presented in this report. A predictive model using the bundle of capillary tube approach has been developed to predict the performance of free gravity drainage process. In Section II, a mechanistic Parachor model has been proposed for improved prediction of IFT as well as to characterize the mass transfer effects for miscibility development in reservoir crude oil-solvent systems. Sensitivity studies on model results indicate that provision of a single IFT measurement in the proposed model is sufficient for reasonable IFT predictions. An attempt has been made to correlate the exponent (n) in the mechanistic model with normalized solute compositions present in both fluid phases. IFT measurements were carried out in a standard ternary liquid system of benzene, ethanol and water using drop shape analysis and capillary rise techniques. The experimental results indicate strong correlation among the three thermodynamic properties solubility, miscibility and IFT. The miscibility determined from IFT measurements for this ternary liquid system is in good agreement with phase diagram and solubility data, which clearly indicates the sound conceptual basis of VIT technique to determine fluid-fluid miscibility. Model fluid systems have been identified for VIT experimentation at elevated pressures and temperatures. Section III comprises of the experimental study aimed at evaluating the multiphase displacement characteristics of the various gas injection EOR process performances using Berea sandstone cores. During this reporting period, extensive literature review was completed to: (1) study the gravity drainage concepts, (2) identify the various factors influencing gravity stable gas injection processes, (3) identify various multiphase mechanisms and fluid dynamics operative during the GAGD process, and (4) identify important dimensionless groups governing the GAGD process performance. Furthermore, the dimensional analysis of the GAGD process, using Buckingham-Pi theorem to isolate the various dimensionless groups, as well as experimental design based on these dimensionless quantities have been completed in this reporting period. On the experimental front, recommendations from previous WAG and CGI have been used to modify the experimental protocol. This report also includes results from scaled preliminary GAGD displacements as well as the details of the planned GAGD corefloods for the next quarter. The technology transfer activities have mainly consisted of preparing technical papers, progress reports and discussions with industry personnel for possible GAGD field tests.« less

Drainage after Modified Radical Mastectomy – A Methodological Mini-Review

PubMed Central

Tsocheva, Dragostina; Marinova, Katerina; Dobrev, Emil; Nenkov, Rumen

2017-01-01

Breast cancer is a socially relevant group of malignant conditions of the mammary gland, affecting both males and females. Most commonly the surgical approach of choice is a modified radical mastectomy (MRM), due to it allowing for both the removal of the main tumor mass and adjacent glandular tissue, which are suspected of infiltration and multifocality of the process, and a sentinel axillary lymph node removal. Most common post-surgical complications following MRM are the formation of a hematoma, the infection of the surgical wound and the formation of a seroma. These post-surgical complications can, at least in part, be attributed to the drainage of the surgical wound. However, the lack of modern and official guidelines provides an ample scope for innovation, but also leads to a need for a randomized comparison of the results. We compared different approaches to wound drainage after MRM, reviewed based on the armamentarium, number of drains, location, type of drainage system, timing of drain removal and no drainage alternatives. Currently, based on the general results, scientific and comparative discussions, seemingly the most affordable methodology with the best patient outcome, with regards to hospital stay and post-operative complications, is the placement of one medial to lateral (pectoro-axillary) drain with low negative pressure. Ideally, the drain should be removed on the second or third postoperative day or when the amount of drained fluid in the last 24 hours reaches below 50 milliliters. PMID:28929038

Importance of anthropogenic climate impact, sampling error and urban development in sewer system design.

PubMed

Egger, C; Maurer, M

2015-04-15

Urban drainage design relying on observed precipitation series neglects the uncertainties associated with current and indeed future climate variability. Urban drainage design is further affected by the large stochastic variability of precipitation extremes and sampling errors arising from the short observation periods of extreme precipitation. Stochastic downscaling addresses anthropogenic climate impact by allowing relevant precipitation characteristics to be derived from local observations and an ensemble of climate models. This multi-climate model approach seeks to reflect the uncertainties in the data due to structural errors of the climate models. An ensemble of outcomes from stochastic downscaling allows for addressing the sampling uncertainty. These uncertainties are clearly reflected in the precipitation-runoff predictions of three urban drainage systems. They were mostly due to the sampling uncertainty. The contribution of climate model uncertainty was found to be of minor importance. Under the applied greenhouse gas emission scenario (A1B) and within the period 2036-2065, the potential for urban flooding in our Swiss case study is slightly reduced on average compared to the reference period 1981-2010. Scenario planning was applied to consider urban development associated with future socio-economic factors affecting urban drainage. The impact of scenario uncertainty was to a large extent found to be case-specific, thus emphasizing the need for scenario planning in every individual case. The results represent a valuable basis for discussions of new drainage design standards aiming specifically to include considerations of uncertainty. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effects of conservation practices on phosphorus loss reduction from an Indiana agricultural watershed

USDA-ARS?s Scientific Manuscript database

Phosphorus losses from agricultural lands have caused serious eutrophication problems, particularly in Lake Erie. However, techniques that can effectively reduce total and soluble phosphorus losses from croplands and drainage channels can be difficult to implement and gauge. This modeling study was ...

Challenges for understanding Antarctic surface hydrology and ice-shelf stability

NASA Astrophysics Data System (ADS)

Kingslake, J.; Bell, R. E.; Banwell, A. F.; Boghosian, A.; Spergel, J.; Trusel, L. D.

2017-12-01

It is widely hypothesized that surface meltwater can contribute to ice mass loss in Antarctica through its impact on ice-shelf stability. Meltwater potentially expedites ice-shelf calving by flowing into and enlarging existing crevasses, and could even trigger ice-shelf disintegration via stresses generated by melt ponds. When ice shelves collapse, the adjacent grounded ice accelerates and thins, which contributes to sea-level rise. How these mechanisms mediate the interactions between the atmosphere, the ocean and the ice sheet is the subject of long-standing research efforts. The drainage of water across the surface of the Antarctic Ice Sheet and its ice shelves is beginning to be recognized as another important aspect of the system. Recent studies have revealed that surface meltwater drainage is more widespread than previously thought and that surface hydrological systems in Antarctica may expand and proliferate this century. Contrasting hypotheses regarding the impact of the proliferation of drainage systems on ice-shelf stability have emerged. Surface drainage could deliver meltwater to vulnerable area or export meltwater from ice shelves entirely. Which behavior dominates may have a large impact on the future response of the Antarctic Ice Sheet to atmospheric warming. We will discuss these recent discoveries and hypotheses, as well as new detailed studies of specific areas where hydrological systems are well developed, such as Amery and Nimrod Ice Shelves. We will highlight analogies that can be drawn with Greenlandic (near-)surface hydrology and, crucially, where hydrological systems on the two ice sheets are very different, leading to potentially important gaps in our understanding. Finally, we will look ahead to the key questions that we argue will need to be if we are to determine the role Antarctic surface hydrology could play in the future of the ice sheet. These include: Where does meltwater pond today and how will this change this century? What coupled glaciological-hydrological dynamics control how drainage systems will change as melt rates increase this century? How do we incorporate surface hydrology into ice-sheet models? While we may be currently unable to answer these and related questions, we aim to start the discussion on how the community can move towards answering them in the future.

The role of CT-guided percutaneous drainage of loculated air collections: an institutional experience.

PubMed

Patel, Bhavik N; Morgan, Madeline; Tyler, Douglas; Paulson, Erik; Jaffe, Tracy A

2015-10-01

The purpose of this study is to describe our experience with the role of CT-guided percutaneous drainage of loculated intra-abdominal collections consisting entirely of gas. An IRB-approved retrospective study analyzing patients with air-only intra-abdominal collections over an 8-year period was undertaken. Seven patients referred for percutaneous drainage were included. Size of collections, subsequent development of fluid, and microbiological yield were determined. Clinical outcome was also analyzed. Out of 2835 patients referred for percutaneous drainage between 2004 and 2012, seven patients (5M, 2F; average age 63, range 54-85) met criteria for inclusion with CT showing air-only collections. Percutaneous drain placement (five 8 Fr, one 10 Fr, and one 12 Fr) using Seldinger technique was performed. Four patients (57%) had recently undergone surgery (2 Whipple, 1 colectomy, 1 hepatic resection) while two (29%) had a remote surgery (1 abdominoperineal resection, 1 sigmoidectomy). Despite the lack of detectable fluid on the original CT, 6 patients (86%) had air and fluid aspirated at drainage, 5 (83%) of the aspirates developed positive microbacterial cultures. Four patients (57%) presented with fever at the time of the initial scan, all of whom had positive cultures from aspirated fluid. Four patients (57%) had leukocytosis, all of whom had positive cultures from aspirated fluid. Although relatively rare in occurrence, patients with air-only intra-abdominal collections with signs of infection should be considered for percutaneous management similar to that of conventional infected fluid collections. Although fluid is not visible on CT, these collections can produce fluid that contains organisms.

Evaluating DEM conditioning techniques, elevation source data, and grid resolution for field-scale hydrological parameter extraction

NASA Astrophysics Data System (ADS)

Woodrow, Kathryn; Lindsay, John B.; Berg, Aaron A.

2016-09-01

Although digital elevation models (DEMs) prove useful for a number of hydrological applications, they are often the end result of numerous processing steps that each contains uncertainty. These uncertainties have the potential to greatly influence DEM quality and to further propagate to DEM-derived attributes including derived surface and near-surface drainage patterns. This research examines the impacts of DEM grid resolution, elevation source data, and conditioning techniques on the spatial and statistical distribution of field-scale hydrological attributes for a 12,000 ha watershed of an agricultural area within southwestern Ontario, Canada. Three conditioning techniques, including depression filling (DF), depression breaching (DB), and stream burning (SB), were examined. The catchments draining to each boundary of 7933 agricultural fields were delineated using the surface drainage patterns modeled from LiDAR data, interpolated to a 1 m, 5 m, and 10 m resolution DEMs, and from a 10 m resolution photogrammetric DEM. The results showed that variation in DEM grid resolution resulted in significant differences in the spatial and statistical distributions of contributing areas and the distributions of downslope flowpath length. Degrading the grid resolution of the LiDAR data from 1 m to 10 m resulted in a disagreement in mapped contributing areas of between 29.4% and 37.3% of the study area, depending on the DEM conditioning technique. The disagreements among the field-scale contributing areas mapped from the 10 m LiDAR DEM and photogrammetric DEM were large, with nearly half of the study area draining to alternate field boundaries. Differences in derived contributing areas and flowpaths among various conditioning techniques increased substantially at finer grid resolutions, with the largest disagreement among mapped contributing areas occurring between the 1 m resolution DB DEM and the SB DEM (37% disagreement) and the DB-DF comparison (36.5% disagreement in mapped areas). These results demonstrate that the decision to use one DEM conditioning technique over another, and the constraints of available DEM data resolution and source, can greatly impact the modeled surface drainage patterns at the scale of individual fields. This work has significance for applications that attempt to optimize best-management practices (BMPs) for reducing soil erosion and runoff contamination within agricultural watersheds.

TECHNICAL GUIDANCE DOCUMENT: QUALITY ASSURANCE AND QUALITY CONTROL FOR WASTE CONTAINMENT FACILITIES

EPA Science Inventory

This Technical Guidance Document provides comprehensive guidance on procedures for quality assurance and quality control for waste containment facilities. he document includes a discussion of principles and concepts, compacted soil liners, soil drainage systems, geosynthetic drai...

TECHNICAL GUIDANCE DOCUMENT: QUALITY ASSURANCE AND QUALITY CONTROL FOR WASTE CONTAINMENT FACILITIES

EPA Science Inventory

This Technical Guidance Document provides comprehensive guidance on procedures for quality assurance and quality control for waste containment facilities. The document includes a discussion of principles and concepts, compacted soil liners, soil drainage systems, geosynthetic dr...

Intraoperative Ultrasonography during Drainage for Chronic Subdural Hematomas: A Technique to Release Isolated Deep-seated Hematomas—Technical Note

PubMed Central

SHIMIZU, Satoru; MOCHIZUKI, Takahiro; OSAWA, Shigeyuki; KUMABE, Toshihiro

2015-01-01

After the drainage of chronic subdural hematomas (CSDHs), residual isolated deep-seated hematomas (IDHs) may recur. We introduce intraoperative ultrasonography to detect and remove such IDHs. Intra-operative ultrasonography is performed with fine transducers introduced via burr holes. Images obtained before dural opening show the CSDHs, hyper- and/or hypoechoic content, and mono- or multilayers. Images are also acquired after irrigation of the hematoma under the dura. Floating hyperechoic spots (cavitations) on the brain cortex created by irrigation confirm the release of all hematoma layers; areas without spots represent IDHs. Their overlying thin membranes are fenestrated with a dural hook for irrigation. Ultrasonographs were evaluated in 43 CSDHs (37 patients); 9 (21%) required IDH fenestration. On computed tomography scans, 17 were homogeneous-, 6 were laminar-, 16 were separated-, and 4 were trabecular type lesions. Of these, 2 (11.8%), 3 (50%), 4 (25%), and 0, respectively, manifested IDHs requiring fenestration. There were no technique-related complications. Patients subjected to IDH fenestration had lower recurrence rates (11.1% vs. 50%, p = 0.095) and required significantly less time for brain re-expansion (mean 3.78 ± 1.62 vs. 18 ± 5.54 weeks, p = 0.0009) than did 6 patients whose IDHs remained after 48 conventional irrigation and drainage procedures. Intraoperative ultrasonography in patients with CSDHs facilitates the safe release of hidden IDHs. It can be expected to reduce the risk of postoperative hematoma recurrence and to shorten the brain re-expansion time. PMID:26345671

A high-vacuum wound drainage system reduces pain and length of treatment for pediatric soft tissue abscesses.

PubMed

Yang, Chao; Wang, Shan; Li, Chang-Chun; Kong, Xiang-Ru; Zhao, Zhenzhen; Deng, Xiao-Bin; Peng, Liang; Zhang, Jun

2017-02-01

Open incision and drainage (I&D) and wound packing is accepted as the standard treatment for soft tissue abscesses. However, conventional I&D has a number of problems in practice which prompt us to improve the I&D methods that would minimize the pain associated with packing during dressing changes. In order to compare the pain associated with dressing changes in the conventional I&D group to the vacuum system group and the treatment time of both groups, we performed a randomized trial in pediatric patients between 0 and 18 years of age who are undergoing abscess drainage in the operating room from April 2011 to April 2015. Patients treated with open I&D (n = 648) were compared to those treated with placement of high-vacuum wound drainage system (n = 776) through the abscess cavities. Both groups received equivalent antibiotic treatment, and all patients were followed up in the outpatient clinics until the infection has been resolved. The mean FACES scale pain scores were significantly higher in the open I&D group than in the vacuum system group. The vacuum system group had a shorter length of stay and less need for community doctor or outpatient dressing changes than the open I&D group (p < 0.001). No recurrent abscesses were observed in the vacuum system group, and 10 patients in the open I&D group required another drainage at the exact same location. High-vacuum wound drainage system was an efficient and safe alternative to the traditional I&D for community-acquired soft tissue abscesses with few complications in short term. What is Known: • Open incision and drainage (I&D) followed by irrigation and wound packing is the standard treatment for soft tissue abscesses. • The painful daily packing may cause emotional trauma to the child and lead to an unwelcoming challenge to the caretakers and health care providers. What is New: • We modified the method of I&D by adding primary suturing of the wound and placement of a high-vacuum wound drainage system. • This technique was proved to be an efficient and safe alternative to the traditional I&D method for soft tissue abscesses with small complications in short term.

Comparison of Irrigation Water Use Estimates Calculated from Remotely Sensed Irrigated Acres and State Reported Irrigated Acres in the Lake Altus Drainage Basin, Oklahoma and Texas, 2000 Growing Season

USGS Publications Warehouse

Masoner, J.R.; Mladinich, C.S.; Konduris, A.M.; Smith, S. Jerrod

2003-01-01

Increased demand for water in the Lake Altus drainage basin requires more accurate estimates of water use for irrigation. The U.S. Geological Survey, in cooperation with the U.S. Bureau of Reclamation, is investigating new techniques to improve water-use estimates for irrigation purposes in the Lake Altus drainage basin. Empirical estimates of reference evapotranspiration, crop evapotranspiration, and crop irrigation water requirements for nine major crops were calculated from September 1999 to October 2000 using a solar radiation-based evapotranspiration model. Estimates of irrigation water use were calculated using remotely sensed irrigated crop acres derived from Landsat 7 Enhanced Thematic Mapper Plus imagery and were compared with irrigation water-use estimates calculated from irrigated crop acres reported by the Oklahoma Water Resources Board and the Texas Water Development Board for the 2000 growing season. The techniques presented will help manage water resources in the Lake Altus drainage basin and may be transferable to other areas with similar water management needs. Irrigation water use calculated from the remotely sensed irrigated acres was estimated at 154,920 acre-feet; whereas, irrigation water use calculated from state reported irrigated crop acres was 196,026 acre-feet, a 23 percent difference. The greatest difference in irrigation water use was in Carson County, Texas. Irrigation water use for Carson County, Texas, calculated from the remotely sensed irrigated acres was 58,555 acrefeet; whereas, irrigation water use calculated from state reported irrigated acres was 138,180 acre-feet, an 81 percent difference. The second greatest difference in irrigation water use occurred in Beckham County, Oklahoma. Differences between the two irrigation water use estimates are due to the differences of irrigated crop acres derived from the mapping process and those reported by the Oklahoma Water Resources Board and Texas Water Development Board.

Estimation of flood discharges at selected annual exceedance probabilities for unregulated, rural streams in Vermont, with a section on Vermont regional skew regression

USGS Publications Warehouse

Olson, Scott A.; with a section by Veilleux, Andrea G.

2014-01-01

This report provides estimates of flood discharges at selected annual exceedance probabilities (AEPs) for streamgages in and adjacent to Vermont and equations for estimating flood discharges at AEPs of 50-, 20-, 10-, 4-, 2-, 1-, 0.5-, and 0.2-percent (recurrence intervals of 2-, 5-, 10-, 25-, 50-, 100-, 200-, and 500-years, respectively) for ungaged, unregulated, rural streams in Vermont. The equations were developed using generalized least-squares regression. Flood-frequency and drainage-basin characteristics from 145 streamgages were used in developing the equations. The drainage-basin characteristics used as explanatory variables in the regression equations include drainage area, percentage of wetland area, and the basin-wide mean of the average annual precipitation. The average standard errors of prediction for estimating the flood discharges at the 50-, 20-, 10-, 4-, 2-, 1-, 0.5-, and 0.2-percent AEP with these equations are 34.9, 36.0, 38.7, 42.4, 44.9, 47.3, 50.7, and 55.1 percent, respectively. Flood discharges at selected AEPs for streamgages were computed by using the Expected Moments Algorithm. To improve estimates of the flood discharges for given exceedance probabilities at streamgages in Vermont, a new generalized skew coefficient was developed. The new generalized skew for the region is a constant, 0.44. The mean square error of the generalized skew coefficient is 0.078. This report describes a technique for using results from the regression equations to adjust an AEP discharge computed from a streamgage record. This report also describes a technique for using a drainage-area adjustment to estimate flood discharge at a selected AEP for an ungaged site upstream or downstream from a streamgage. The final regression equations and the flood-discharge frequency data used in this study will be available in StreamStats. StreamStats is a World Wide Web application providing automated regression-equation solutions for user-selected sites on streams.

Morphotectonics of the Jamini River basin, Bundelkhand Craton, Central India; using remote sensing and GIS technique

NASA Astrophysics Data System (ADS)

Prakash, K.; Mohanty, T.; Pati, J. K.; Singh, S.; Chaubey, K.

2017-11-01

Morphological and morphotectonic analyses have been used to obtain information that influence hydrographic basins, predominantly these are modifications of tectonic elements and the quantitative description of landforms. Discrimination of morphotectonic indices of active tectonics of the Jamini river basin consists the analyses of asymmetry factor, ruggedness number, basin relief, gradient, basin elongation ratio, drainage density analysis, and drainage pattern analysis, which have been completed for each drainage basin using remote sensing and GIS techniques. The Jamini river is one of the major tributaries of the Betwa river in central India. The Jamini river basin is divided into five subwatersheds viz. Jamrar, Onri, Sainam, Shahzad and Baragl subwatershed. The quantitative approach of watershed development of the Jamini river basin, and its four sixth (SW1-SW4) and one fifth (SW5) order subwatersheds, was carried out using Survey of India toposheets (parts of 54I, 54K, 54L, 54O, and 54P), Landsat 7 ETM+, ASTER (GDEM) data, and field data. The Jamini river has low bifurcation index which is a positive marker of tectonic imprint on the hydrographic network. The analyses show that the geomorphological progression of the study area was robustly influenced by tectonics. The analysis demonstrates to extensional tectonics system with the following alignments: NE-SW, NW-SE, NNE-SSW, ENE-WSW, E-W, and N-S. Three major trends are followed by lower order streams viz. NE-SW, NW-SE, and E-W directions which advocate that these tectonic trends were active at least up to the Late Pleistocene. The assessment of morphotectonic indices may be used to evaluate the control of active faults on the hydrographic system. The analysis points out westward tilting of the drainage basins with strong asymmetry in some reaches, marked elongation ratio of subwatersheds, and lower order streams having close alignment with lineaments (active faults). The study facilitated to considerate the function of active tectonism in the advancement of the basin.

Photostabilization of a landfill containing coal combustion waste

Treesearch

Christopher Barton; Donald Marx; Domy Adriano; Bon Jun Koo; Lee Newman; Stephen Czapka; John Blake

2005-01-01

The establishment of a vegetative cover to enhance evapotranspiration and control runoff and drainage was examined as a method for stabilizing a landfill containing coal combustion waste. Suitable plant species and pretreatment techniques in the form of amendments, tilling, and chemical stabilization were evaluated. A randomized plot design consisting of three...

Phytostabilization of a landfill containing coal combustion waste

Treesearch

Christopher Barton; Donald Marx; Domy Adriano; Bon Jun Koo; Lee Newman; Stephen Czapka; John Blake

2005-01-01

The establishment of a vegetative cover to enhance evapotranspiration and control runoff and drainage was examined as a method for stabilizing a landfill containing coal combustion waste. Suitable plant species and pretreatment techniques in the form of amendments, tilling, and chemical stabilization were evaluated. A randomized plot design consisting of three...

The development of the deterministic nonlinear PDEs in particle physics to stochastic case

NASA Astrophysics Data System (ADS)

Abdelrahman, Mahmoud A. E.; Sohaly, M. A.

2018-06-01

In the present work, accuracy method called, Riccati-Bernoulli Sub-ODE technique is used for solving the deterministic and stochastic case of the Phi-4 equation and the nonlinear Foam Drainage equation. Also, the control on the randomness input is studied for stability stochastic process solution.

[Pancreatic pseudocyst in children: what is the best therapeutic approach?].

PubMed

Nouira, F; Ben Ahmed, Y; Sarrai, N; Ghorbel, S; Jlidi, S; Chaouachi, B

2011-11-01

Pancreatic pseudocyst is an uncommon disorder in children and the majority of reported cases are secondary to trauma. Treatment options range from medical management to different forms of drainage procedure. The aim of this study was to discuss therapeutic strategies. The authors report herein pancreatic pseudocyst in four children aged 7, 9, 12, and 13 years with non-resolving pancreatic pseudocyst over a 2-year period from January 2006 to July 2008. The etiology of pancreatic pseudocyst was abdominal trauma in two cases and acute pancreatitis in two cases. Ultrasound and computed tomography scans confirmed the diagnosis. Two patients had endoscopic drainage. There were no procedure-related complications, nor was there a recurrence of the cyst. In one case, the pancreatic pseudocyst resolved spontaneously. This report suggests that children with non-spontaneously resolving pancreatic pseudocyst can be treated successfully and safely with endoscopic drainage. Surgical treatment remains an important alternative in the therapeutic armamentarium of this affection. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

Development of sustainable stormwater management using simulation-optimization approach under climate change

NASA Astrophysics Data System (ADS)

Huang, Yu-ru; Tung, Ching-pin

2015-04-01

Climate change had altered the hydrological processes globally with result that the extreme events have an increase in both the magnitude and the frequency. In particular, the high intensity rainfall cause the severe flooding had significantly impacted on human life and property in recently year. The traditional facility to handle runoff is the drainage system which is designed in accordance with the intensity-duration-frequency (IDF) curve. However, the flooding occurs once the drainage capacity is overwhelmed by excess stormwater. Thus the general solution are that expanding and upgrading the existing drainage system or increasing the design return period for new development areas to reduce flooding. Besides, another technique which is low impact development(LID) is regarded as more sustainable solution for stormwater management. The concept of LID is to control stormwater at the source by decentralized practices and mimic the predevelopment hydrologic conditions including storage, retention and high rate of infiltration. In contrast to conventional drainage system aims to move runoff away as quickly as possible, the LID approach attempts to keep runoff on site to reduce peak and volume of flow. The purpose of this research is to identify the most cost-effective measures for stormwater management after the analysis of the strategies combining drainage system and LID on various land use planning. The case study is a rural community in Hsinchu in Taiwan, and having residential areas, farms and pond. It is assumed that two land use layout are planned and drainage system are designed for 2-,and 5-year return period events. On the other hand, three LID technologies, namely green roof, porous pavement and rain barrel, are selected to place in the scenario of the drainage system for 2-year return period event, and the minimal peak flow is target to optimize LID placement by simulated annealing algorithm. Moreover, the design storm under climate change are derived from the revised IDF curve. After that the storm water management model (SWMM) is used to simulate these strategies for a spectrum of design storms, the cost and the benefit can be analyzed to provide government an advice in developing stormwater management under uncertain conditions of climate change.

Singularity-sensitive gauge-based radar rainfall adjustment methods for urban hydrological applications

NASA Astrophysics Data System (ADS)

Wang, L.-P.; Ochoa-Rodríguez, S.; Onof, C.; Willems, P.

2015-09-01

Gauge-based radar rainfall adjustment techniques have been widely used to improve the applicability of radar rainfall estimates to large-scale hydrological modelling. However, their use for urban hydrological applications is limited as they were mostly developed based upon Gaussian approximations and therefore tend to smooth off so-called "singularities" (features of a non-Gaussian field) that can be observed in the fine-scale rainfall structure. Overlooking the singularities could be critical, given that their distribution is highly consistent with that of local extreme magnitudes. This deficiency may cause large errors in the subsequent urban hydrological modelling. To address this limitation and improve the applicability of adjustment techniques at urban scales, a method is proposed herein which incorporates a local singularity analysis into existing adjustment techniques and allows the preservation of the singularity structures throughout the adjustment process. In this paper the proposed singularity analysis is incorporated into the Bayesian merging technique and the performance of the resulting singularity-sensitive method is compared with that of the original Bayesian (non singularity-sensitive) technique and the commonly used mean field bias adjustment. This test is conducted using as case study four storm events observed in the Portobello catchment (53 km2) (Edinburgh, UK) during 2011 and for which radar estimates, dense rain gauge and sewer flow records, as well as a recently calibrated urban drainage model were available. The results suggest that, in general, the proposed singularity-sensitive method can effectively preserve the non-normality in local rainfall structure, while retaining the ability of the original adjustment techniques to generate nearly unbiased estimates. Moreover, the ability of the singularity-sensitive technique to preserve the non-normality in rainfall estimates often leads to better reproduction of the urban drainage system's dynamics, particularly of peak runoff flows.

Recovery and reuse of sludge from active and passive treatment of mine drainage-impacted waters: a review.

PubMed

Rakotonimaro, Tsiverihasina V; Neculita, Carmen Mihaela; Bussière, Bruno; Benzaazoua, Mostafa; Zagury, Gérald J

2017-01-01

The treatment of mine drainage-impacted waters generates considerable amounts of sludge, which raises several concerns, such as storage and disposal, stability, and potential social and environmental impacts. To alleviate the storage and management costs, as well as to give the mine sludge a second life, recovery and reuse have recently become interesting options. In this review, different recovery and reuse options of sludge originating from active and passive treatment of mine drainage are identified and thoroughly discussed, based on available laboratory and field studies. The most valuable products presently recovered from the mine sludge are the iron oxy-hydroxides (ochre). Other by-products include metals, elemental sulfur, and calcium carbonate. Mine sludge reuse includes the removal of contaminants, such as As, P, dye, and rare earth elements. Mine sludge can also be reused as stabilizer for contaminated soil, as fertilizer in agriculture/horticulture, as substitute material in construction, as cover over tailings for acid mine drainage prevention and control, as material to sequester carbon dioxide, and in cement and pigment industries. The review also stresses out some of the current challenges and research needs. Finally, in order to move forward, studies are needed to better estimate the contribution of sludge recovery/reuse to the overall costs of mine water treatment.

Regional equations for estimation of peak-streamflow frequency for natural basins in Texas

USGS Publications Warehouse

Asquith, William H.; Slade, Raymond M.

1997-01-01

Peak-streamflow frequency for 559 Texas stations with natural (unregulated and rural or nonurbanized) basins was estimated with annual peak-streamflow data through 1993. The peak-streamflow frequency and drainage-basin characteristics for the Texas stations were used to develop 16 sets of equations to estimate peak-streamflow frequency for ungaged natural stream sites in each of 11 regions in Texas. The relation between peak-streamflow frequency and contributing drainage area for 5 of the 11 regions is curvilinear, requiring that one set of equations be developed for drainage areas less than 32 square miles and another set be developed for drainage areas greater than 32 square miles. These equations, developed through multiple-regression analysis using weighted least squares, are based on the relation between peak-streamflow frequency and basin characteristics for streamflow-gaging stations. The regions represent areas with similar flood characteristics. The use and limitations of the regression equations also are discussed. Additionally, procedures are presented to compute the 50-, 67-, and 90-percent confidence limits for any estimation from the equations. Also, supplemental peak-streamflow frequency and basin characteristics for 105 selected stations bordering Texas are included in the report. This supplemental information will aid in interpretation of flood characteristics for sites near the state borders of Texas.

Ice-­Ocean Thermodynamic Interface and Small-­Scale Issues

DOE Office of Scientific and Technical Information (OSTI.GOV)

Turner, Adrian K.

2012-07-02

This presentation discusses: (1) Stefan condition, (2) lower boundary condition of mushy layers, (3) salt flux to ocean from gravity drainage, (4) distribution of salt flux in the ocean, (5) under ice melt ponds and false bottoms, and (6) basal ablation.

Long-Term Impacts of Forest Ditching on Non-Aquatic Biodiversity: Conservation Perspectives for a Novel Ecosystem

PubMed Central

Remm, Liina; Lõhmus, Piret; Leis, Mare; Lõhmus, Asko

2013-01-01

Artificial drainage (ditching) is widely used to increase timber yield in northern forests. When the drainage systems are maintained, their environmental impacts are likely to accumulate over time and along accompanying management, notably after logging when new forest develops on decayed peat. Our study provides the first comprehensive documentation of long-term ditching impacts on terrestrial and arboreal biodiversity by comparing natural alder swamps and second-generation drained forests that have evolved from such swamps in Estonia. We explored species composition of four potentially drainage-sensitive taxonomic groups (vascular plants, bryophytes, lichens, and snails), abundance of species of conservation concern, and their relationships with stand structure in two-ha plots representing four management types (ranging from old growth to clearcut). We found that drainage affected plot-scale species richness only weakly but it profoundly changed assemblage composition. Bryophytes and lichens were the taxonomic groups that were most sensitive both to drainage and timber-harvesting; in closed stands they responded to changed microhabitat structure, notably impoverished tree diversity and dead-wood supply. As a result, natural old-growth plots were the most species-rich and hosted several specific species of conservation concern. Because the most influential structural changes are slow, drainage impacts may be long hidden. The results also indicated that even very old drained stands do not provide quality habitats for old-growth species of drier forest types. However, drained forests hosted many threatened species that were less site type specific, including early-successional vascular plants and snails on clearcuts and retention cuts, and bryophytes and lichens of successional and old forests. We conclude that three types of specific science-based management tools are needed to mitigate ditching effects on forest biodiversity: (i) silvicultural techniques to maintain stand structural complexity; (ii) context-dependent spatial analysis and planning of drained landscapes; and (iii) lists of focal species to monitor and guide ditching practices. PMID:23646179

Anomalous pulmonary venous connection: An underestimated entity.

PubMed

Magalhães, Sara P; Moreno, Nuno; Loureiro, Marília; França, Manuela; Reis, Fernanda; Alvares, Sílvia; Ribeiro, Manuel

2016-12-01

Anomalous pulmonary venous connection is an uncommon congenital anomaly in which all (total form) or some (partial form) pulmonary veins drain into a systemic vein or into the right atrium rather than into the left atrium. The authors present one case of total anomalous pulmonary venous connection and two cases of partial anomalous pulmonary venous connection, one of supracardiac drainage into the brachiocephalic vein, and the other of infracardiac anomalous venous drainage (scimitar syndrome). Through the presentation of these cases, this article aims to review the main pulmonary venous developmental defects, highlighting the role of imaging techniques in the assessment of these anomalies. Copyright © 2016 Sociedade Portuguesa de Cardiologia. Publicado por Elsevier España, S.L.U. All rights reserved.

Experimental research of gas shale electrical properties by NMR and the combination of imbibition and drainage

NASA Astrophysics Data System (ADS)

Dong, Xu; Sun, Jianmeng; Li, Jun; Gao, Hui; Liu, Xuefeng; Wang, Jinjie

2015-08-01

Gas shale has shown considerable force in gas production worldwide, but little attention has been paid to its electrical properties, which are essential for reservoir evaluation and differentiating absorbed gas and free gas. In this study, experiments are designed to research water saturation establishment methods and electrical properties of gas shale. Nuclear magnetic resonance (NMR) with short echo space (TE) is used to identify water saturation and distribution of saturated pores which contribute to the conductivity. The experimental results indicate that NMR with shorter TE can estimate porosity and fluid distribution better than NMR with longer TE. A full range of water saturation is established by the combination of new-type spontaneous imbibition and semi-permeable plate drainage techniques. Spontaneous imbibition gains water saturation from 0% to near irreducible water saturation, and, semi-permeable plate drainage desaturates from 100% to irreducible water saturation. The RI-Sw curve shows a nonlinear relationship, and can be divided into three parts with different behaviors. The comparative analysis of transverse relaxation time (T2) distribution and RI-Sw curves, indicates that free water, and water trapped by capillarity in the non-clay matrix, differ in terms of electrical conductivity from water absorbed in clay. The new experiments prove the applicability of imbibition, drainage and NMR in investigating electrical properties of gas shale and differentiating fluid distribution which makes contribution to conductivity.

A new technique for variable-load cholangiomanometry. Implication for biliary tract surgery.

PubMed

Nagakawa, T; Konishi, I; Ueno, K; Ohta, T; Kayahara, M; Yoshimitsu, Y; Suzaki, Y; Tukioka, Y; Sanada, H; Miyazaki, I

1997-01-01

Variable-load cholangiomanometry was performed to obtain data on terminal biliary function during the surgical treatment of cholelithiasis. The decision of whether or not to perform a definitive biliary drainage procedure was based on the results of this test. The rate of perfusion was reduced in four steps from 15.3 ml/min to 1.2 ml/min, and the resultant perfusion pressures were plotted. The gradient produced by the straight line was considered the resistance, R. The baseline pressure without perfusion was regarded as the static pressure, P. A review of 444 patients with cholelithiasis who underwent intraoperative cholangiomanometry during the past 11 years led to the following indications for definitive biliary drainage: (1) R > 10 units and P > 200 mm H2O, (2) if only R or P is elevated, priority is given to R, and (3) if the elevation of R or P is borderline, the presence of a type I curvature in the segment of low flow rate is an indication for surgery. By performing an intraoperative cholangiomanometry concrete indications for a biliary drainage procedure can be defined.

[Diagnostic and therapeutic approach to pancreatic trauma].

PubMed

Vidali, Maria; Doulgerakis, George; Condilis, Nicolas; Karmiri, Eleni; Poygouras, Ihon; Papaioannoy, George; Ioannoy, Christos; Pierrakakis, Stefanos; Setakis, Nicolas

2005-01-01

The pancreatic trauma is rare, compared with the injuries of the other abdominal organs and occurs in 0.2-6 per cent of the cases of abdominal trauma. The aim of this essay is to demonstrate the Authors' experience in the treatment of five cases of pancreatic injury during the last five years, as well as to retrospect the contemporary bibliography, connected with the diagnostic and curative approach of the pancreatic trauma. The diagnosis of the pancreatic trauma is difficult and many times, late. In their experience of pancreatic trauma, the Authors ascertained the pancreatic injury during the laparotomy which was made in order to treat other abdominal injuries. The surgical techniques were chosen taking into account the extent of the injury, the detection and the existence of accompanying. Marginal resection of pancreas, splenectomy and drainage were applied to three patients, suture of the pancreas and drainage to one patient, drainage alone and treatment of synchronous rupture of the duodenum to one patient. The mortality was 0%. Came whereas the morbidity came basically on the seriousness of the accompanying injuries.

Experimental flow studies in glaucoma drainage device development.

PubMed

2001-10-01

(I) To examine whether small holes produced by 248 nm excimer laser ablation in a polymer substrate could consistently produce a pressure drop in the desired target range (5-15 mm Hg) at physiological aqueous flow rates for use as an internal flow restrictor in a glaucoma drainage device, and (ii) to investigate whether external leakage could be reduced in comparison with conventional tube and plate glaucoma drainage devices by redesigning the exterior cross sectional shape of the portion contained within the sclerocorneal tunnel. Single holes with target diameters of 10 microm, 15 microm, 20 microm, and 25 microm were drilled using a 248 nm excimer laser in sample discs (n=6 at each diameter) punched from a 75 microm thick polyimide sheet. Sample discs were tested in a flow rig designed to measure the pressure drop across the discs. Using filtered, degassed water at a flow rate of 1.4 microl/min repeated flow measurements were taken (n=6) for each disc. After flow testing, all discs were imaged using a scanning electron microscope and the dimensions of each hole were derived using image analysis software. In the external leakage study, corneoscleral buttons (n=13) were prepared from cadaver pig eyes and mounted on an artificial anterior chamber infused with Tyrode solution. After the pressure had stabilised, standard occluded silicone tube implants were inserted through 23 gauge needle stab incisions at the limbus. These were compared against prototype PMMA implants with a novel shape profile inserted through 1.15 mm width microvitreoretinal (MVR) stab incisions at the limbus. The infusion rate was maintained and a second pressure measurement was taken when the pressure had stabilised. The difference between the first and second pressure measurement was then compared, as an index of external leakage. Ablated tubes were found to have a near perfect circular outline on both the entry and exit side. The observed pressure drops across the ablated sample discs at each target diameter were as follows: 10 microm, mean 25.66 (SD 4.9) mm Hg; 15 microm, 6.7 (1.15); 20 microm, 1.66 (1.07); and 25 microm, <0.1 mm Hg. A strong correlation was observed between observed pressure drops and those predicted by Poiseuille's formula (R(2) =0.996). Target ablations of 15 microm diameter produced tubes that consistently achieved a pressure drop within the desired range (5-15 mm Hg). In the external leakage study, preinsertion pressures (mm Hg; mean (SD)) were 19.00 (4.3) (conventional method) and 20.00 (3.9) (new technique with PMMA prototypes). Post-insertion pressures were significantly reduced (10.40 (7.7); p<0.01) for the conventional technique and were essentially unchanged for the new technique (18.80 (4.9); p>0.1). It was shown that it is possible, in principle, to control the dimensions of a manufactured tubular lumen in a glaucoma drainage device accurately enough to provide consistent protection from hypotony in the early period after glaucoma filtration surgery. By redesigning the external profile of glaucoma drainage device and incision technique, it was also shown that it is possible to eliminate uncontrolled external leakage.

Drainage basin characteristics from ERTS data

NASA Technical Reports Server (NTRS)

Hollyday, E. F. (Principal Investigator)

1975-01-01

The author has identified the following significant results. ERTS-derived measurements of forests, riparian vegetation, open water, and combined agricultural and urban land use were added to an available matrix of map-derived basin characteristics. The matrix of basin characteristics was correlated with 40 stream flow characteristics by multiple regression techniques. Fifteen out of the 40 equations were improved. If the technique can be transferred to other physiographic regions in the nation, the opportunity exists for a potential annual savings in operations of about $250,000.

Multivariate Bias Correction Procedures for Improving Water Quality Predictions from the SWAT Model

NASA Astrophysics Data System (ADS)

Arumugam, S.; Libera, D.

2017-12-01

Water quality observations are usually not available on a continuous basis for longer than 1-2 years at a time over a decadal period given the labor requirements making calibrating and validating mechanistic models difficult. Further, any physical model predictions inherently have bias (i.e., under/over estimation) and require post-simulation techniques to preserve the long-term mean monthly attributes. This study suggests a multivariate bias-correction technique and compares to a common technique in improving the performance of the SWAT model in predicting daily streamflow and TN loads across the southeast based on split-sample validation. The approach is a dimension reduction technique, canonical correlation analysis (CCA) that regresses the observed multivariate attributes with the SWAT model simulated values. The common approach is a regression based technique that uses an ordinary least squares regression to adjust model values. The observed cross-correlation between loadings and streamflow is better preserved when using canonical correlation while simultaneously reducing individual biases. Additionally, canonical correlation analysis does a better job in preserving the observed joint likelihood of observed streamflow and loadings. These procedures were applied to 3 watersheds chosen from the Water Quality Network in the Southeast Region; specifically, watersheds with sufficiently large drainage areas and number of observed data points. The performance of these two approaches are compared for the observed period and over a multi-decadal period using loading estimates from the USGS LOADEST model. Lastly, the CCA technique is applied in a forecasting sense by using 1-month ahead forecasts of P & T from ECHAM4.5 as forcings in the SWAT model. Skill in using the SWAT model for forecasting loadings and streamflow at the monthly and seasonal timescale is also discussed.

Liver abscess caused by tuberculosis and melioidosis.

PubMed

Azali, Hafiz Yafee Amar; Norly, Salleh; Wong, Leh Meng; Tan, Kia Sin; Safian, Naim Muhammad

2007-04-01

We report an unusual co-existence of Burkholderia pseudomallei and acid fast bacilli in a young Malay gentleman with liver abscess. He was treated with antibiotics and surgical drainage. This phenomenon has not been reported in previous literature and the dilemma of its management is discussed.

First branchial cleft anomalies: avoiding the misdiagnosis.

PubMed

Kumar, Rajeev; Sikka, Kapil; Sagar, Prem; Kakkar, Aanchal; Thakar, Alok

2013-07-01

First branchial cleft anomalies are a very rare entities accounting for less than 1 % of all branchial cleft malformations. They are often misdiagnosed for other cystic lesions occurring in parotid gland and inadequately treated (incision and drainage or incomplete excision) leading to multiple recurrences. We report a series of four patients who were previously operated (incision and drainage) for misdiagnosed first branchial cleft anomalies with subsequent recurrences. All patients underwent superficial parotidectomy with complete tract excision using facial nerve monitoring to prevent iatrogenic injury because of extensive fibrosis. We discuss the literature pertaining to first branchial cleft anomalies, their varied presentations and their relationship to facial nerve in parotid gland and importance of facial nerve monitoring in revision surgery.

Atlas of Ohio Aquatic Insects: Volume II, Plecoptera.

PubMed

DeWalt, R Edward; Grubbs, Scott A; Armitage, Brian J; Baumann, Richard W; Clark, Shawn M; Bolton, Michael J

2016-01-01

We provide volume II of a distributional atlas of aquatic insects for the eastern USA state of Ohio. This treatment of stoneflies (Plecoptera) is companion to Armitage et al. (2011) on caddisflies (Trichoptera). We build on a recent analysis of Ohio stonefly diversity patterns based on large drainages (DeWalt et al. 2012), but add 3717 new records to the data set. We base most analyses on the United States Geological Survey Hierarchical Unit Code eight (HUC8) drainage scale. In addition to distributional maps for each species, we provide analyses of species richness versus HUC8 drainage area and the number of unique locations in a HUC8 drainage, species richness versus Ohio counties, analyze adult presence phenology throughout the year, and demonstrate stream size range affiliation for each species. This work is based on a total of 7797 specimen records gathered from 21 regional museums, agency data, personal collections, and from the literature Table 1. To our knowledge this is the largest stonefly data set available for a similarly sized geopolitical area anywhere in the world. These data are made available as a Darwin Core Archive supported by the Pensoft Integrated Publishing Toolkit (DeWalt et al. 2016b). All known published papers reporting stoneflies from Ohio are detailed in Suppl. material 1. We recovered 102 species from Ohio, including all nine Nearctic families Table 2​. Two species were removed from the DeWalt et al. (2012) list and two new state records added. Perlidae (32 spp.) was most speciose, compared to the low diversity Pteronarcyidae (2 spp.) and Peltoperlidae (1 sp.). The richest HUC8 drainages occurred in northeastern, south-central, and southern regions of the state where drainages were heavily forested, had the highest slopes, and were contained within or adjacent to the unglaciated Allegheny and Appalachian Plateaus. Species poor drainages occurred mainly in the northwestern region where Wisconsinan aged lake plains climaxed to an expansive wooded wetland, the Black Swamp. The unglaciated Lower Scioto drainage (72 spp.) in south-central Ohio supported the greatest species richness. There was no relationship between species richness and HUC8 drainage size, but the number of unique locations in a drainage strongly related to species richness. All Ohio counties were represented in the data set with Hocking County (59 spp.) of the Lower Scioto drainage being the richest and most heavily sampled. Adult presence phenology was influenced by phylogenetic relationships such that the superfamily Nemouroidea (Capniidae, Leuctridae, Nemouridae, and Taeniopterygidae) generally emerged in winter and spring while the superfamilies Pteronarcyoidea (Pteronarcyidae, Peltoperlidae) and Perloidea (Chloroperlidae, Perlidae, Perlodidae) emerged later, some species continuing emergence through summer months. Species often occupied specific stream size ranges, while others were generalists. Two species once histrorically abundant in the western Lake Erie Bass Islands no longer reside there. Each of the 102 species is discussed in detail, including several that require additional collecting efforts to confirm their identities, presence, and distribution in Ohio.

Accurate seismic phase identification and arrival time picking of glacial icequakes

NASA Astrophysics Data System (ADS)

Jones, G. A.; Doyle, S. H.; Dow, C.; Kulessa, B.; Hubbard, A.

2010-12-01

A catastrophic lake drainage event was monitored continuously using an array of 6, 4.5 Hz 3 component geophones in the Russell Glacier catchment, Western Greenland. Many thousands of events and arrival time phases (e.g., P- or S-wave) were recorded, often with events occurring simultaneously but at different locations. In addition, different styles of seismic events were identified from 'classical' tectonic earthquakes to tremors usually observed in volcanic regions. The presence of such a diverse and large dataset provides insight into the complex system of lake drainage. One of the most fundamental steps in seismology is the accurate identification of a seismic event and its associated arrival times. However, the collection of such a large and complex dataset makes the manual identification of a seismic event and picking of the arrival time phases time consuming with variable results. To overcome the issues of consistency and manpower, a number of different methods have been developed including short-term and long-term averages, spectrograms, wavelets, polarisation analyses, higher order statistics and auto-regressive techniques. Here we propose an automated procedure which establishes the phase type and accurately determines the arrival times. The procedure combines a number of different automated methods to achieve this, and is applied to the recently acquired lake drainage data. Accurate identification of events and their arrival time phases are the first steps in gaining a greater understanding of the extent of the deformation and the mechanism of such drainage events. A good knowledge of the propagation pathway of lake drainage meltwater through a glacier will have significant consequences for interpretation of glacial and ice sheet dynamics.

[Percutaneous ultrasound-guided drainage in the surgical treatment of acute severe pancreatitis].

PubMed

Delattre, J-F; Levy Chazal, N; Lubrano, D; Flament, J-B

2004-11-01

To report results of percutaneous ultrasound-guided drainage, performed by a surgeon, in the treatment of complications of acute pancreatitis (AP), and to determine the role of this technique in the therapeutic armamentarium of severe AP. From 1986 to 2001, 59 patients were included in this retrospective study. All patients initially had severe necrotizing AP (mean Ranson score = 4.1 ; range : 2-7). Anatomical lesions included pancreatic abscess in 6 patients and necrosis in 53 (17 stage D and 36 stage E according to Balthazar's classification). Necrosis was infected in 42 and sterile in 11 respectively. Drainage was performed under ultrasound guidance and local anaesthesia using small-diameter drains (7-14 French). Drainage was performed on average 23 days after onset of AP. Infection was proven by fine-needle aspiration in 47 (80 %) patients (41 infected necrosis and 6 localized abscess). In one patient, culture of aspirated fluid was negative but necrosis was infected (one false negative). Culture of aspirated fluid was negative and necrosis was sterile in 11 patients. Nineteen (32%) patients healed without subsequent surgery: 7 (16%) in the infected necrosis group, 6(55%) in the sterile necrosis group, and 6 (100%) in the abscess group. Forty (68%) patients had subsequent necrosectomy including 8 (14%) who died. Twenty (34 %) digestive fistulas healed spontaneously, except one treated by diversion stomia. Of the 16 (27 %) pancreatic fistulas, 6 needed subsequent interventional treatment. In selected patients, percutaneous drainage can represent an alternative to surgery with a 14% mortality rate. The high rate of subsequent necrosectomy suggests that drains with larger diameter, possibly associated with continuous irrigation, should be used.

Time-integrated Monitoring of Polychlorinated Dibenzo-p-dioxins and Polychlorinated Dibenzofurans (PCDD/Fs) in Urban and Industrial Wastewaters Using a Ceramic Toximeter and the CALUX Bioassay

PubMed Central

Addeck, Amr; Croes, Kim; Van Langenhove, Kersten; Denison, Michael S.; Elhamalawy, Ahmed; Elskens, Marc; Baeyens, Willy

2015-01-01

The ceramic toximeter as a passive sampler in combination with the CALUX bioassay was utilized as a time-integrated pollution-assessment technique for dioxin-like PCDD/Fs in wastewaters. Toximeters filled with XCARB and enclosed in stainless steel cages were submerged in wastewater of Belbeis drainage-canal and EMAK paper-mill, located in Egypt, for 28 days. Two samplers were removed every week from each site. Extracts from toximeters, from bottom-sediments, and from paper-mill sludge were analyzed by the CALUX. Results showed a regular increase in the amounts of PCDD/Fs trapped by the toximeters as sampling time increased. Time-weighted average concentrations (TWA) of PCDD/Fs in the wastewaters of the drainage-canal and paper-mill were 231 (214-281) and 26 (24.1-32.6) pg-BEQ L-1, respectively. Compared to literature data, this means a high pollution level for the drainage-canal water, while the pollution level in the paper-mill wastewater is similar to that reported for other paper mills. The PCDD/Fs levels in the drainage-canal bottom-sediments and in the paper-mill sludge were 8.3 and 14.6 pg-BEQ g-1 dry-weight, at the lower end of internationally reported values in similar compartments. The sampling rate of the tested toximeters for dissolved PCDD/Fs was about 3.6 mL d-1. Sediment/water partitioning coefficient log Kd of PCDD/Fs in the drainage-canal and the paper-mill was 1.42 and 2.70 respectively. The organic-carbon normalized partition coefficient log Koc was 4.17 and 3.19 respectively, and is lower than the reported values for other sites. PMID:24075528

Time-integrated monitoring of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) in urban and industrial wastewaters using a ceramic toximeter and the CALUX bioassay.

PubMed

Addeck, Amr; Croes, Kim; Van Langenhove, Kersten; Denison, Michael S; Elhamalawy, Ahmed; Elskens, Marc; Baeyens, Willy

2014-01-01

The ceramic toximeter as a passive sampler in combination with the CALUX bioassay was utilized as a time-integrated pollution-assessment technique for dioxin-like PCDD/Fs in wastewaters. Toximeters filled with XCARB and enclosed in stainless steel cages were submerged in wastewater of Belbeis drainage-canal and EMAK paper-mill, located in Egypt, for 28 days. Two samplers were removed every week from each site. Extracts from toximeters, from bottom-sediments, and from paper-mill sludge were analyzed by the CALUX. Results showed a regular increase in the amounts of PCDD/Fs trapped by the toximeters as sampling time increased. Time-weighted average concentrations (TWA) of PCDD/Fs in the wastewaters of the drainage-canal and paper-mill were 231 (214-281) and 26 (24.1-32.6) pg-BEQL(-1), respectively. Compared to literature data, this means a high pollution level for the drainage-canal water, while the pollution level in the paper-mill wastewater is similar to that reported for other paper mills. The PCDD/Fs levels in the drainage-canal bottom-sediments and in the paper-mill sludge were 8.3 and 14.6 pg-BEQg(-1) dry-weight, at the lower end of internationally reported values in similar compartments. The sampling rate of the tested toximeters for dissolved PCDD/Fs was about 3.6 mL d(-1). Sediment/water partitioning coefficient logKd of PCDD/Fs in the drainage-canal and the paper-mill was 1.42 and 2.70 respectively. The organic-carbon normalized partition coefficient logKoc was 4.17 and 3.19 respectively, and is lower than the reported values for other sites. Copyright © 2013 Elsevier Ltd. All rights reserved.

Direct-seedling pines in the south

Treesearch

Harold J. Derr; William F. Mann

1971-01-01

Direct seeding of the southern pines is a versatile reforestation technique that is being widely accepted by land managers. On many sites it is more economical than planting nursery-grown seedlings or waiting for natural reproduction. It is applicable on some sites where access, terrain, or drainage conditions make planting difficult. Commercial trials have proved it...

Application of LANDSAT images to the study of level soils for recognizing drainage areas. Thesis Paper

NASA Technical Reports Server (NTRS)

Espinoza, M. U.

1977-01-01

Photographic images from LANDSAT 1 were applied to the study of soil in Desaguadero, Bolivia, in order to locate areas with high agricultural and livestock potential. Photointerpretation techniques were emphasized and advantages of information obtained via multispectral satellite images in various bands and combinations were demonstrated.

Knee arthroplasty and bleeding: when to remove drainages.

PubMed

Ares, Oscar; Seijas, Roberto; Hernandez, Alberto; Castellet, Enric; Sallent, Andrea

2013-02-01

The aim of this study is an attempt to clarify the productive time of drainages as we find that the use of drains in knee arthroplasty is controversial, and there is no consensus regarding their length-time maintenance. We analysed the survival curve of bleeding within three surgical techniques for knee arthroplasty and the effect of two variables on survival curve. One hundred and eighty-eight out of 234 knees were included in the study, and patients were divided into three groups according to the surgical technique: conventional total knee arthroplasty (TKA), subvastus TKA and unicompartmental knee arthroplasty. Variables of study were type of surgery, number and placement of drains. Mean of survival curve for postoperative bleeding time was 16 h (95 % CI: 15.4; 16.6). The risk for longer bleeding increased 1.38-fold with each additional drain used (95 % CI 1.1; 1.8). According to the present study, drains can be safely removed at around 17 h postoperative. Bleeding time reduces as less drains are applied. Therapeutic study, Level III.

Vacuum sealing drainage therapy in the presence of an external fixation device

PubMed Central

Sun, Dahui; Ju, Weina; Wang, Tiejun; Yu, Tiecheng; Qi, Baochang

2016-01-01

Abstract Rationale: Vacuum sealing drainage (VSD) is widely utilized for treating traumatic wounds. Patient concerns: It is particularly difficult and time consuming to use in combination with an external fixator. Diagnoses: This is because the hardware or pins used for fixation interfere with maintaining a seal, resulting in poor adhesion and subsequent air leakage. Interventions: To resolve this problem, we have devised a new method for sealing the wound dressing, while maintaining the required vacuum.When using this technique, a rubber strip is wrapped around each pin in 3 circles outside the plastic drape, and then tightly tied. Outcomes: After completing this procedure, a vacuum is obtained, and any air leakage stops. We employed this technique to treat a cohort of patients in our department over a period of two years, and obtained good healing of soft tissue without air leakage, as well as good clinical outcomes. Lessons: We have observed that patients treated with this method experienced good clinical outcomes without air leakage, and we recommend its use in treating cases where an external fixation device is present. PMID:27861393

Minimally invasive surgical treatment of malignant pleural effusions.

PubMed

Ciuche, Adrian; Nistor, Claudiu; Pantile, Daniel; Prof Horvat, Teodor

2011-10-01

Usually the pleural cavity contains a small amount of liquid (approximately 10 ml). Pleural effusions appear when the liquid production rate overpasses the absorption rate with a greater amount of liquid inside the pleural cavity. Between January 1998 to December 2008 we conducted a study in order to establish the adequate surgical treatment for MPEs. Effective control of a recurrent malignant pleural effusion can greatly improve the quality of life of the cancer patient. The present review collects and examines the clinical results of minimally invasive techniques designed to treat this problem. Patients with MPEs were studied according to several criteria. In our study we observed the superiority of intraoperative talc poudrage, probably due to a more uniform distribution of talc particles over the pleural surface. Minimal pleurotomy with thoracic drainage and instillation of a talc suspension is also a safe and effective technique and should be employed when there are contraindications for the thoracoscopic minimally invasive procedure. On the basis of comparisons involving effectiveness, morbidity, and convenience, we recommend the thoracoscopic insufflations of talc as a fine powder with pleural drainage as the procedure of choice.

Muscle gap approach under a minimally invasive channel technique for treating long segmental lumbar spinal stenosis

PubMed Central

Bin, Yang; De cheng, Wang; wei, Wang Zong; Hui, Li

2017-01-01

Abstract This study aimed to compare the efficacy of muscle gap approach under a minimally invasive channel surgical technique with the traditional median approach. In the Orthopedics Department of Traditional Chinese and Western Medicine Hospital, Tongzhou District, Beijing, 68 cases of lumbar spinal canal stenosis underwent surgery using the muscle gap approach under a minimally invasive channel technique and a median approach between September 2013 and February 2016. Both approaches adopted lumbar spinal canal decompression, intervertebral disk removal, cage implantation, and pedicle screw fixation. The operation time, bleeding volume, postoperative drainage volume, and preoperative and postoperative visual analog scale (VAS) score and Japanese Orthopedics Association score (JOA) were compared between the 2 groups. All patients were followed up for more than 1 year. No significant difference between the 2 groups was found with respect to age, gender, surgical segments. No diversity was noted in the operation time, intraoperative bleeding volume, preoperative and 1 month after the operation VAS score, preoperative and 1 month after the operation JOA score, and 6 months after the operation JOA score between 2 groups (P > .05). The amount of postoperative wound drainage (260.90 ± 160 mL vs 447.80 ± 183.60 mL, P < .001) and the VAS score 6 months after the operation (1.71 ± 0.64 vs 2.19 ± 0.87, P = .01) were significantly lower in the muscle gap approach group than in the median approach group (P < .05). In the muscle gap approach under a minimally invasive channel group, the average drainage volume was reduced by 187 mL, and the average VAS score 6 months after the operation was reduced by an average of 0.48. The muscle gap approach under a minimally invasive channel technique is a feasible method to treat long segmental lumbar spinal canal stenosis. It retains the integrity of the posterior spine complex to the greatest extent, so as to reduce the adjacent spinal segmental degeneration and soft tissue trauma. Satisfactory short-term and long-term clinical results were obtained. PMID:28796075

High soil solution carbon und nitrogen concentrations in a drained Atlantic bog are reduced to natural levels by 10 yr of rewetting

NASA Astrophysics Data System (ADS)

Frank, S.; Tiemeyer, B.; Gelbrecht, J.; Freibauer, A.

2013-10-01

Artificial drainage of peatlands causes dramatic changes in the release of greenhouse gases and in the export of dissolved carbon (C) and nutrients to downstream ecosystems. Rewetting anthropogenically altered peatlands offers a possibility to reduce nitrogen (N) and C losses. In this study, we investigate the impact of drainage and rewetting on the cycling of dissolved C and N as well as on dissolved gases over a period of 1 yr and 4 month, respectively. The peeper technique was used to receive a high vertical sampling resolution. Within one Atlantic bog complex a near natural site, two drained grasslands sites with different mean water table positions, and a former peat cutting area rewetted 10 yr ago were chosen. Our results clearly indicate that drainage increased the concentration of dissolved organic carbon (DOC), ammonia, nitrate and dissolved organic nitrogen (DON) compared to the near natural site. Drainage depth further determined the release and therefore the concentration level of DOC and N species, but the biochemical cycling and therefore dissolved organic matter (DOM) quality and N species composition were unaffected. Thus, especially deep drainage can cause high DOC losses. In general, DOM at drained sites was enriched in aromatic moieties as indicated by SUVA280 and showed a higher degradation status (lower DOC to DON ratio) compared to the near natural site. At the drained sites, equal C to N ratios of uppermost peat layer and DOC to DON ratio of DOM in soil solution suggest that the uppermost degraded peat layer is the main source of DOM. Nearly constant DOC to DON ratios and SUVA280 values with depth furthermore indicated that DOM moving downwards through the drained sites remained largely unchanged. DON and ammonia contributed most to the total dissolved nitrogen (TN). The subsoil concentrations of nitrate were negligible due to strong decline in nitrate around mean water table depth. Methane production during the winter months at the drained sites moved downwards to areas which were mostly water saturated over the whole year (>40 cm). Above these depths, the recovery of the water table in winter months led to the production of nitrous oxide around mean water table depth at drained sites. 10 yr after rewetting, the DOM quality (DOC to DON ratio and SUVA280) and quantity were comparable to the near natural site, indicating the re-establishment of mostly pristine biochemical processes under continuously water logged conditions. The only differences occur in elevated dissolved methane and ammonia concentrations reflecting the former disturbance by drainage and peat extraction. Rewetting via polder technique seems to be an appropriate way to revitalize peatlands on longer timescales and to improve the water quality of downstream water bodies.

Thoracoscopic anterior ‘fissure first’ technique for left lung cancer with an incomplete fissure

PubMed Central

Samejima, Joji; Matsuura, Yosuke; Nakao, Masayuki; Uehara, Hirofumi; Nakagawa, Ken; Masuda, Munetaka; Okumura, Sakae

2016-01-01

Background Dealing with incomplete lung fissures during thoracoscopic surgery is difficult. Our objective was to evaluate the efficacy and safety of a thoracoscopic anterior ‘fissure first’ technique for dealing with incomplete left lung fissures. Methods One hundred and seventy patients underwent left upper lobectomy or left lower lobectomy between April 2008 and July 2014. Of these, 34 patients underwent surgery using a thoracoscopic anterior ‘fissure first’ technique for incomplete fissures (group A) and 136 underwent surgery using a conventional thoracoscopic method for unfused fissures (group B). A four-port complete thoracoscopic approach was used in all patients. After completion of the fissure, hilar lymphadenectomy was performed in the conventional manner. Results There were no significant differences between the two groups in operating time, blood loss, or duration of chest tube drainage. Patients in group A required more staple cartridges than those in group B (mean number of cartridges, 2.4 vs. 1.1; P<0.01). The two groups did not significantly differ with regard to the prevalence of air leaks (12% vs. 4%; P=0.11), either prolonged or delayed. Conclusions We found that a thoracoscopic anterior ‘fissure first’ technique for left lung cancer with an incomplete fissure enabled hilar lymphadenectomy to be performed in the conventional manner without any increase in the prevalence of air leaks, operating time, or duration of chest tube drainage. This technique should be considered for use in left upper lobectomy or left lower lobectomy in patients with an incomplete fissure. PMID:28066589

Strength and Conditioning for the Person with Cystic Fibrosis.

ERIC Educational Resources Information Center

Waller, Mike

2001-01-01

Discusses how a strength and conditioning program can be safety incorporated into the daily life of people with cystic fibrosis as a complementary therapy to medications, regular checkups, bronchial drainage, and respiratory therapy, examining physical restrictions and guidelines, exercise prescriptions, and exercise applications, and explaining…

A Top Pilot Tunnel Preconditioning Method for the Prevention of Extremely Intense Rockbursts in Deep Tunnels Excavated by TBMs

NASA Astrophysics Data System (ADS)

Zhang, Chuanqing; Feng, Xiating; Zhou, Hui; Qiu, Shili; Wu, Wenping

2012-05-01

The headrace tunnels at the Jinping II Hydropower Station cross the Jinping Mountain with a maximum overburden depth of 2,525 m, where 80% of the strata along the tunnels consist of marble. A number of extremely intense rockbursts occurred during the excavation of the auxiliary tunnels and the drainage tunnel. In particular, a tunnel boring machine (TBM) was destroyed by an extremely intense rockburst in a 7.2-m-diameter drainage tunnel. Two of the four subsequent 12.4-m-diameter headrace tunnels will be excavated with larger size TBMs, where a high risk of extremely intense rockbursts exists. Herein, a top pilot tunnel preconditioning method is proposed to minimize this risk, in which a drilling and blasting method is first recommended for the top pilot tunnel excavation and support, and then the TBM excavation of the main tunnel is conducted. In order to evaluate the mechanical effectiveness of this method, numerical simulation analyses using the failure approaching index, energy release rate, and excess shear stress indices are carried out. Its construction feasibility is discussed as well. Moreover, a microseismic monitoring technique is used in the experimental tunnel section for the real-time monitoring of the microseismic activities of the rock mass in TBM excavation and for assessing the effect of the top pilot tunnel excavation in reducing the risk of rockbursts. This method is applied to two tunnel sections prone to extremely intense rockbursts and leads to a reduction in the risk of rockbursts in TBM excavation.

[Evidence-based ways of colorectal anastomotic complications prevention in the setting of digestive deep endometriosis resection: CNGOF-HAS Endometriosis Guidelines].

PubMed

Loriau, J; Petit, E; Mephon, A; Angliviel, B; Sauvanet, E

2018-03-01

Management of deep pelvic and digestive endometriosis can lead to colorectal resection and anastomosis. Colorectal anastomosis carries risks for dreaded infectious and functional morbidity. The aim of the study was to establish, regarding the published data, the role of the three most common used surgical techniques to prevent such complications: pelvic drainage, diverting stoma, epiplooplasty. Even if many studies and articles have focused on colorectal anastomotic leakage prevention in rectal cancer surgery data regarding this topic in the setting of endometriosis where lacking. Due to major differences between the two situations, patients, diseases the use of the conclusions from the literature have to be taken with caution. In 4 randomized controlled trials the usefulness of systematic postoperative pelvic drainage hasn't been demonstrated. As this practice is not systematically recommended in cancer surgery, its interest is not demonstrated after colorectal resection for endometriosis. There is a heavy existing literature supporting systematic diverting stoma creation after low colorectal anastomosis for rectal cancer. Keeping in mind the important differences between the two situations, the conclusions cannot be directly extrapolated. In endometriosis surgery after low rectal resection, stoma creation must be discussed and the patient must be informed and educated about this possibility. Even if widely used there is no data supporting the role of epiplooplasty in colorectal anastomotic complication prevention? The place for epiplooplasty in preventing rectovaginal fistula occurrence in case of concomitant resection hasn't been studied. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

EARLYDRAIN- outcome after early lumbar CSF-drainage in aneurysmal subarachnoid hemorrhage: study protocol for a randomized controlled trial

PubMed Central

2011-01-01

Background Aneurysmal subarachnoid hemorrhage (SAH) may be complicated by delayed cerebral ischemia, which is a major cause of unfavorable clinical outcome and death in SAH-patients. Delayed cerebral ischemia is presumably related to the development of vasospasm triggered by the presence of blood in the basal cisterns. To date, oral application of the calcium antagonist nimodipine is the only prophylactic treatment for vasospasm recognized under international guidelines. In retrospective trials lumbar drainage of cerebrospinal fluid has been shown to be a safe and feasible measure to remove the blood from the basal cisterns and decrease the incidence of delayed cerebral ischemia and vasospasm in the respective study populations. However, the efficacy of lumbar drainage has not been evaluated prospectively in a randomized controlled trial yet. Methods/Design This is a protocol for a 2-arm randomized controlled trial to compare an intervention group receiving early continuous lumbar CSF-drainage and standard neurointensive care to a control group receiving standard neurointensive care only. Adults suffering from a first aneurysmal subarachnoid hemorrhage whose aneurysm has been secured by means of coiling or clipping are eligible for trial participation. The effect of early CSF drainage (starting < 72 h after securing the aneurysm) will be measured in the following ways: the primary endpoint will be disability after 6 months, assessed by a blinded investigator during a personal visit or standardized telephone interview using the modified Rankin Scale. Secondary endpoints include mortality after 6 months, angiographic vasospasm, transcranial Doppler sonography (TCD) mean flow velocity in both middle cerebral arteries and rate of shunt insertion at 6 months after hospital discharge. Discussion Here, we present the study design of a multicenter prospective randomized controlled trial to investigate whether early application of a lumbar drainage improves clinical outcome after aneurysmal subarachnoid hemorrhage. Trial registration www.clinicaltrials.gov Identifier: NCT01258257 PMID:21917146

The assessment of Urban Storm Inundation

NASA Astrophysics Data System (ADS)

Setyandito, Oki; Wijayanti, Yureana; Alwan, Muhammad; Chayati, Cholilul; Meilani

2017-12-01

A Sustainable and integrated plan in order to solve urban storm inundation problem, is an urgent issue in Indonesia. A reliable and complete datasets of urban storm inundation area in Indonesia should become its basis to give clear description of inundation area for formulating the best solution. In this study, Statistics Indonesia data in thirty three provinces were assessed during 2000 until 2012 providing data series of urban flood area, flood frequency and land cover changes. Drainage system condition in big cities should be well understood to ensure its infrastructure condition and performance. If inundation occurred, it can be concluded that there is drainage system problem. Inundation data is also important for drainage system design process in the future. The study result is provided estimation of urban storm inundation area based on calculation of Statistics Indonesia data. Moreover, this study is preceded by analyzing and reviewing the capacity of existing drainage channel, using case study of Mataram, West Nusa Tenggara. Rainfall data was obtained from three rainfall stations surround Mataram City. The storm water quantity was calculated using three different approaches as follows: 1) Rational Method; 2) Summation of existing inundation and surface run off discharge; 3) Discharge calculation from existing channel dimensions. After that, the result of these approaches was compared. The storm water quantity gap was concluded as quantity of inundation. The result shows that 36% of drainage channel in Brenyok Kanan River sub system could not accommodate the storm water runoff in this area, which causing inundation. The redesign of drainage channel using design discharge from Rational Method approach should be performed. Within area with the lowest level topography, a construction of detention or storage pond is essential to prevent inundation in this area. Furthermore, the benefits and drawbacks of the statistics database are discussed. Recommendations include utilizing more refined urban land use typologies that can better represent physical alteration of hydrological pathways

Estimating the magnitude of peak flows for streams in Kentucky for selected recurrence intervals

USGS Publications Warehouse

Hodgkins, Glenn A.; Martin, Gary R.

2003-01-01

This report gives estimates of, and presents techniques for estimating, the magnitude of peak flows for streams in Kentucky for recurrence intervals of 2, 5, 10, 25, 50, 100, 200, and 500 years. A flowchart in this report guides the user to the appropriate estimates and (or) estimating techniques for a site on a specific stream. Estimates of peak flows are given for 222 U.S. Geological Survey streamflow-gaging stations in Kentucky. In the development of the peak-flow estimates at gaging stations, a new generalized skew coefficient was calculated for the State. This single statewide value of 0.011 (with a standard error of prediction of 0.520) is more appropriate for Kentucky than the national skew isoline map in Bulletin 17B of the Interagency Advisory Committee on Water Data. Regression equations are presented for estimating the peak flows on ungaged, unregulated streams in rural drainage basins. The equations were developed by use of generalized-least-squares regression procedures at 187 U.S. Geological Survey gaging stations in Kentucky and 51 stations in surrounding States. Kentucky was divided into seven flood regions. Total drainage area is used in the final regression equations as the sole explanatory variable, except in Regions 1 and 4 where main-channel slope also was used. The smallest average standard errors of prediction were in Region 3 (from -13.1 to +15.0 percent) and the largest average standard errors of prediction were in Region 5 (from -37.6 to +60.3 percent). One section of this report describes techniques for estimating peak flows for ungaged sites on gaged, unregulated streams in rural drainage basins. Another section references two previous U.S. Geological Survey reports for peak-flow estimates on ungaged, unregulated, urban streams. Estimating peak flows at ungaged sites on regulated streams is beyond the scope of this report, because peak flows on regulated streams are dependent upon variable human activities.

[Comparative study on Chinese medical syndrome typing and treatment combined different surgical methods for treating clomiphene-resistant polycystic ovary syndrome].

PubMed

Zeng, Lei; Zeng, Cheng; Tao, Li-Li

2012-11-01

To observe the therapeutic efficacy of Chinese medical syndrome typing and treatment combined cold needle puncture drainage operation or unipolar electrocoagulation drilling technique under laparoscope for treating clomiphene-resistant polycystic ovary syndrome (PCOS). Forty infertility patients with clomiphene-resistant PCOS were assigned to two groups using stratified random sampling method according to age, infertility time, and body mass index, 20 in each group. Patients in Group A were treated with Chinese medical syndrome typing and treatment combined cold needle puncture drainage operation, while those in Group B were treated with Chinese medical syndrome typing and treatment combined unipolar electrocoagulation drilling technique. After operation Chinese herbal treatment was administered to all patients according to syndrome typing. The serum levels of luteinizing hormone (LH), follicle stimulating hormone (FSH), androgen (T), estradiol (E2), and prolactin (PRL) were determined before and after operation. The ovulation was monitored. The pregnancy rate and the pregnancy outcomes were recorded after operation. There was no statistical difference in the 3-month spontaneous ovulation rate or the 1-year pregnancy rate (P > 0.05). The levels of LH, T, and PRL were significantly lower after operation than before operation in the two groups (P < 0.05). The menstruation and ovulation were obviously improved after operation. The total ovulation rate was 95% (19/20) in Group A. Successful pregnancy occurred in 15 cases of Group A. Ovarian hyperstimulation syndrome (OHSS) occurred in 1 case of Group A. The total ovulation rate was 90% (18/20) in Group B. Successful pregnancy occurred in 13 cases of Group B. Hypovaria occurred in 1 case of Group B. Luteinized unruptured follicle (LUFS) occurred in 2 cases of Group A and 1 case of Group B. Chinese medical syndrome typing and treatment combined cold needle puncture drainage operation or unipolar electrocoagulation drilling technique could effectively promote the ovulation. The two methods showed similar therapeutic effects.

Continuous Passive Sampling of Solutes from Agricultural Subsurface Drainage Tubes

NASA Astrophysics Data System (ADS)

Lindblad Vendelboe, Anders; de Jonge, Hubert; Rozemeijer, Joachim; Wollesen de Jonge, Lis

2015-04-01

Agricultural subsurface tube drain systems play an important role in water and solute transport. One study, focusing on lowland agricultural catchments, showed that subsurface tube drainage contributed up to 80% of the annual discharge and 90% of the annual NO3 load from agricultural fields to the receiving water bodies. Knowledge of e.g. nutrient loads and drainage volumes, based on measurements and modelling, are important for adequate water quality management. Despite the importance of tube drain transport of solutes, monitoring data are scarce. This scarcity is a result of the existing monitoring techniques for flow and contaminant load from tube drains being expensive and labor-extensive. The study presented here aimed at developing a cheap, simple, and robust method to monitor solute loads from tube drains. The method is based on the newly developed Flowcap, which can be attached to existing tube drain outlets and can measure total flow, contaminant load and flow-averaged concentrations of solutes in the drainage. The Flowcap builds on the existing Sorbicell principle, a passive sampling system that measures average concentrations over longer periods of time (days to months) for various compounds. The Sorbicell consists of two compartments permeable to water. One compartment contains an adsorbent and one contains a tracer. When water passes through the Sorbicell the compound of interest is absorbed while a tracer is released. Using the tracer loss to calculate the volume of water that has passed the Sorbicell it is possible to calculate the average concentration of the compound. When mounting Sorbicells in the Flowcap, a flow-proportional part of the drainage is sampled from the main stream. To accommodate the wide range of drainage flow rates two Flowcaps with different capacities were tested in the laboratory: one with a capacity of 25 L min-1 (Q25) and one with a capacity of 256 L min-1 (Q256). In addition, Sorbicells with two different hydraulic resistances were tested, again to accommodate a large range of potential drainage flows rates. The experiment was continued until the Sorbicell's capacity was exhausted, which gave experimentation times from 6 to 34 days, while continuously changing the drainage flow rate to simulate field drainage conditions, and to test the range of the Flowcap. The laboratory testing yielded a very good linear correlation between drainage flow rates and Sorbicell sampling rates, giving r = 0.99 for both the Q25 and the Q256 Flowcap. The Sorbicells in this experiment were designed to measure NO3, but the Flowcap can be used with any Sorbicell and thus be used to measure any compound of interest. The Flowcap does not need housing, electricity, or maintenance and continuously register drainage volumes and contaminant loads for periods up to one month. This, in addition to the low cost of the monitoring system, enables large-scale monitoring of contaminant loads via tube drains, giving valuable data for the improvement of contaminant transport models. Further, these data will help select and evaluate the different mitigation option to improve water quality.

T-tube drainage versus primary closure after open common bile duct exploration.

PubMed

Gurusamy, Kurinchi Selvan; Koti, Rahul; Davidson, Brian R

2013-06-21

Between 5% and 11% of people undergoing cholecystectomy have common bile duct stones. Stones may be removed at the time of cholecystectomy by opening and clearing the common bile duct. The optimal technique is unclear. The aim is to assess the benefits and harms of T-tube drainage versus primary closure without biliary stent after open common bile duct exploration for common bile duct stones. We searched the Cochrane Hepato-Biliary Group Controlled Trials Register, Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE, and Science Citation Index Expanded until April 2013. We included all randomised clinical trials comparing T-tube drainage versus primary closure after open common bile duct exploration. Two of four authors independently identified the studies for inclusion and extracted data. We analysed the data with both the fixed-effect and the random-effects model using Review Manager (RevMan) analyses. For each outcome we calculated the risk ratio (RR), rate ratio (RaR), or mean difference (MD) with 95% confidence interval (CI) based on intention-to-treat analysis. We included six trials randomising 359 participants, 178 to T-tube drainage and 181 to primary closure. All trials were at high risk of bias. There was no significant difference in mortality between the two groups (4/178 (weighted percentage 1.2%) in the T-tube group versus 1/181 (0.6%) in the primary closure group; RR 2.25; 95% CI 0.55 to 9.25; six trials). There was no significant difference in the serious morbidity rate between the two groups (24/136 (weighted serious morbidity rate, 145 events per 1000 patients) in the T-tube group versus 9/136 (weighted serious morbidity rate, 66 events per 1000 patients) in the primary closure group; RaR 2.19; 95% CI 0.98 to 4.91; four trials). Quality of life and return to work were not reported in any of the trials. The operating time was significantly longer in the T-tube drainage group compared with the primary closure group (MD 28.90 minutes; 95% CI 17.18 to 40.62 minutes; one trial). The hospital stay was significantly longer in the T-tube drainage group compared with the primary closure group (MD 4.72 days; 95% CI 0.83 days to 8.60 days; five trials). T-tube drainage appeared to result in significantly longer operating time and hospital stay compared with primary closure without any apparent evidence of benefit on clinically important outcomes after open common bile duct exploration. Based on the currently available evidence, there is no justification for the routine use of T-tube drainage after open common bile duct exploration in patients with common bile duct stones. T-tube drainage should not be used outside well designed randomised clinical trials. More randomised trials comparing the effects of T-tube drainage versus primary closure after open common bile duct exploration may be needed. Such trials should be conducted with low risk of bias and assessing the long-term beneficial and harmful effects of T-tube drainage, including long-term complications such as bile stricture and recurrence of common bile duct stones.

Palliation: Hilar cholangiocarcinoma

PubMed Central

Goenka, Mahesh Kr; Goenka, Usha

2014-01-01

Hilar cholangiocarcinomas are common tumors of the bile duct that are often unresectable at presentation. Palliation, therefore, remains the goal in the majority of these patients. Palliative treatment is particularly indicated in the presence of cholangitis and pruritus but is often also offered for high-grade jaundice and abdominal pain. Endoscopic drainage by placing stents at endoscopic retrograde cholangio-pancreatography (ERCP) is usually the preferred modality of palliation. However, for advanced disease, percutaneous stenting has been shown to be superior to endoscopic stenting. Endosonography-guided biliary drainage is emerging as an alternative technique, particularly when ERCP is not possible or fails. Metal stents are usually preferred over plastic stents, both for ERCP and for percutaneous biliary drainage. There is no consensus as to whether it is necessary to place multiple stents within advanced hilar blocks or whether unilateral stenting would suffice. However, recent data have suggested that, contrary to previous belief, it is useful to drain more than 50% of the liver volume for favorable long-term results. In the presence of cholangitis, it is beneficial to drain all of the obstructed biliary segments. Surgical bypass plays a limited role in palliation and is offered primarily as a segment III bypass if, during a laparotomy for resection, the tumor is found to be unresectable. Photodynamic therapy and, more recently, radiofrequency ablation have been used as adjuvant therapies to improve the results of biliary stenting. The exact technique to be used for palliation is guided by the extent of the biliary involvement (Bismuth class) and the availability of local expertise. PMID:25232449

Minimally invasive management of hepatic cysts: indications and complications.

PubMed

Vardakostas, D; Damaskos, C; Garmpis, N; Antoniou, E A; Kontzoglou, K; Kouraklis, G; Dimitroulis, D

2018-03-01

Liver cysts are divided into congenital and acquired. Congenital cystic lesions include polycystic liver disease, simple cysts, duct related and ciliated hepatic foregut cysts. Acquired cystic lesions are divided into infectious and non-infectious. The infectious cysts are the hydatid cyst, the amoebic abscess, and the pyogenic abscess, whereas the non-infectious cysts are neoplastic cysts and false cysts. While modern medicine provides a lot of minimally invasive therapeutic modalities, there has emerged a pressing need for understanding the various types of liver cysts, the possible minimal therapeutic options along with their indications and complications. We aim is to clarify the role of minimally invasive techniques in the management of hepatic cysts. A literature review was performed using the MEDLINE database. The search terms were: liver cyst, minimally invasive, laparoscopic, percutaneous, drainage and fenestration. We reviewed 82 English language publications articles, published until October 2017. Minimally invasive management of liver LC is an emerging field including many therapeutic modalities ranging from the percutaneous aspiration of pyogenic abscesses to laparoscopic hepatectomy for hepatic cystadenomas. The most used techniques are percutaneous drainage, laparoscopic fenestration, and laparoscopic hepatectomy. The application of the various minimally invasive approaches, as well as their indication and complications, depend on the type of the cystic lesion, its size and its position in the liver. Percutaneous drainage is mostly used in simple cysts, hydatid cysts, pyogenic abscesses and bilomas. Laparoscopic fenestration is mostly used in simple cysts and polycystic liver disease. Finally, laparoscopic hepatectomy is mostly used in polycystic liver disease, hydatid cysts, and cystadenomas.

Effects of mechanical massage, manual lymphatic drainage and connective tissue manipulation techniques on fat mass in women with cellulite.

PubMed

Bayrakci Tunay, V; Akbayrak, T; Bakar, Y; Kayihan, H; Ergun, N

2010-02-01

To evaluate and compare the effectiveness of three different noninvasive treatment techniques on fat mass and regional fat thickness of the patients with cellulites. Sixty subjects were randomized into three groups. Group 1 (n = 20) treated with mechanical massage (MM), group 2 (n = 20) treated with manual lymphatic drainage (MLD) and group 3 (n = 20) treated with connective tissue manipulation (CTM) techniques. Subjects were evaluated by using standardized photographs, body composition analyzer (TBF 300) (body weight (BW), body mass index (BMI), fat %, fat mass (FM), fat free mass (FFM), total body water (TBW)), circumference measurement from thigh, waist-hip ratio (WHR), fat thickness measurements from abdomen, suprailium and thigh regions with skin fold caliper. All groups had an improvement in thinning of the subcutaneous fat after the treatment (P < 0.05). Thigh circumference decreased by an average of 0.5 cm in all groups and thigh fat thickness decreased 1.66 mm in Group 1, 2.21 mm in Group 2 and 3.03 mm in Group 3. Abdomen and suprailium fat thicknesses decreased 2.4 and 2.58 mm in Group 1, 1.78 and 2 mm in Group 2 and 1.23 and 0.64 mm in Group 3, respectively. The mean difference in waist-hip ratio was 0.1 cm in all groups. All the treatment techniques are effective in decreasing the regional fat values of the patients with cellulites.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

To evaluate the potential of the Devonian shale as a source of natural gas, the US Department of Energy (DOE) has undertaken the Eastern Gas Shales Project (EGSP). The EGSP is designed not only to identify the resource, but also to test improved methods of inducing permeability to facilitate gas drainage, collection, and production. The ultimate goal of this project is to increase the production of gas from the eastern shales through advanced exploration and exploitation techniques. The purpose of this report is to inform the general public and interested oil and gas operators about EGSP results as they pertainmore » to the Devonian gas shales of the Appalachian basin in Pennsylvania. Geologic data and interpretations are summarized and areas where the accumulation of gas may be large enough to justify commercial production are outlined. Because the data presented in this report are generalized and not suitable for evaluation of specific sites for exploration, the reader should consult the various reports cited for more detail and discussion of the data, concepts, and interpretations presented.« less

Flood-plain delineation for Occoquan River, Wolf Run, Sandy Run, Elk Horn Run, Giles Run, Kanes Creek, Racoon Creek, and Thompson Creek, Fairfax County, Virginia

USGS Publications Warehouse

Soule, Pat LeRoy

1978-01-01

Water-surface profiles of the 25-, 50-, and 100-year recurrence interval discharges have been computed for all streams and reaches of channels in Fairfax County, Virginia, having a drainage area greater than 1 square mile except for Dogue Creek, Little Hunting Creek, and that portion of Cameron Run above Lake Barcroft. Maps having a 2-foot contour interval and a horizontal scale of 1 inch equals 100 feet were used for base on which flood boundaries were delineated for 25-, 50-, and 100-year floods to be expected in each basin under ultimate development conditions. This report is one of a series and presents a discussion of techniques employed in computing discharges and profiles as well as the flood profiles and maps on which flood boundaries have been delineated for the Occoquan River and its tributaries within Fairfax County and those streams on Mason Neck within Fairfax County tributary to the Potomac River. (Woodard-USGS)

Clean Water for the 1970's, A Status Report.

ERIC Educational Resources Information Center

Department of the Interior, Washington, DC. Federal Water Quality Administration.

This report describes the past activities and future plans of the Federal Water Quality Administration (FWQA). The first of the four sections in the report provides general discussion about these forms of water pollution: municipal wastes, industrial wastes, thermal pollution, oil and hazardous substances, mine drainage, sedimentation and erosion,…

Applied Remote Sensing Program (ARSP) to state and local government

NASA Technical Reports Server (NTRS)

Johnson, J. D.; Foster, K. E.; Mouat, D. A.; Clark, R.

1975-01-01

Environmental surveys of arid land areas (Arizona) in the United States are presented. Maps of soils, vegetation, drainage patterns, and land use are shown. The distribution of uranium deposits, oil and gas pools, is also shown. Legislation pertaining to the preservation of natural resources is discussed.

Quarter-Shifted Microincisional Sutureless Vitrectomy in Patients with a Glaucoma Drainage Implant or Filtering Bleb.

PubMed

Song, Ji Hun; Jang, Seran; Cho, Eun Hyung; Ahn, Jaehong

2017-05-01

When vitrectomy is performed in eyes that have undergone glaucoma surgery, the site of sclerotomy often overlaps with the previous glaucoma operation site. It can lead to serious complications such as postoperative hypotony, leakage, and/or infection. Our technique involves modification of surgeon's position and two sclerotomy sites 45° away from the original position, with an infusion cannula inserted infranasally to avoid damage to the glaucoma drainage implant or filtering bleb. The modified approach was applied to seven eyes with various indications. Vitrectomy was successfully completed, and there were no sclerotomy site complications, leakage, or hypotony in any case. Good intraocular pressure control was maintained throughout the postoperative course in all cases. © Copyright: Yonsei University College of Medicine 2017.

A novel approach to model dynamic flow interactions between storm sewer system and overland surface for different land covers in urban areas

NASA Astrophysics Data System (ADS)

Chang, Tsang-Jung; Wang, Chia-Ho; Chen, Albert S.

2015-05-01

In this study, we developed a novel approach to simulate dynamic flow interactions between storm sewers and overland surface for different land covers in urban areas. The proposed approach couples the one-dimensional (1D) sewer flow model (SFM) and the two-dimensional (2D) overland flow model (OFM) with different techniques depending on the land cover type of the study areas. For roads, pavements, plazas, and so forth where rainfall becomes surface runoff before entering the sewer system, the rainfall-runoff process is simulated directly in the 2D OFM, and the runoff is drained to the sewer network via inlets, which is regarded as the input to 1D SFM. For green areas on which rainfall falls into the permeable ground surface and the generated direct runoff traverses terrain, the deduction rate is applied to the rainfall for reflecting the soil infiltration in the 2D OFM. For flat building roofs with drainage facilities allowing rainfall to drain directly from the roof to sewer networks, the rainfall-runoff process is simulated using the hydrological module in the 1D SFM where no rainfall is applied to these areas in the 2D OFM. The 1D SFM is used for hydraulic simulations in the sewer network. Where the flow in the drainage network exceeds its capacity, a surcharge occurs and water may spill onto the ground surface if the pressure head in a manhole exceeds the ground elevation. The overflow discharge from the sewer system is calculated by the 1D SFM and considered a point source in the 2D OFM. The overland flow will return into the sewer network when it reaches an inlet that connects to an un-surcharged manhole. In this case, the inlet is considered as a point sink in the 2D OFM and an inflow to a manhole in the 1D SFM. The proposed approach was compared to other five urban flood modelling techniques with four rainfall events that had previously recorded inundation areas. The merits and drawbacks of each modelling technique were compared and discussed. Based on the simulated results, the proposed approach was found to simulate floodings closer to the survey records than other approaches because the physical rainfall-runoff phenomena in urban environment were better reflected.

Processing of next generation weather radar-multisensor precipitation estimates and quantitative precipitation forecast data for the DuPage County streamflow simulation system

USGS Publications Warehouse

Bera, Maitreyee; Ortel, Terry W.

2018-01-12

The U.S. Geological Survey, in cooperation with DuPage County Stormwater Management Department, is testing a near real-time streamflow simulation system that assists in the management and operation of reservoirs and other flood-control structures in the Salt Creek and West Branch DuPage River drainage basins in DuPage County, Illinois. As part of this effort, the U.S. Geological Survey maintains a database of hourly meteorological and hydrologic data for use in this near real-time streamflow simulation system. Among these data are next generation weather radar-multisensor precipitation estimates and quantitative precipitation forecast data, which are retrieved from the North Central River Forecasting Center of the National Weather Service. The DuPage County streamflow simulation system uses these quantitative precipitation forecast data to create streamflow predictions for the two simulated drainage basins. This report discusses in detail how these data are processed for inclusion in the Watershed Data Management files used in the streamflow simulation system for the Salt Creek and West Branch DuPage River drainage basins.

Lumbar Cerebrospinal Fluid Drainage in Endovascular Aortic Repair - Reference Centre Experience.

PubMed

Martins, Ana Margarida; Silva, Marisa; Castro, Maria de Lurdes; Ferro, Ana

2017-01-01

Spinal cord ischemia (SCI) and the resulting paraplegia are one of the most feared postoperative complications after thoraco-abdominal aortic surgery, with an incidence 4,3-8,0% after thoracic endovascular aortic repair (TEVAR), increasing patients morbi-mortality. Lumbar cerebrospinal fluid (CSF) drainage catheter is recommended as preventive measure in high risk patients. To evaluate the efficiency and safety of CSF drainage catheter as preventive or therapeutic measure in endovascular aortic repair (EAR). Retrospective study in 19 patients submitted to TEVAR or fEVAR (fenestrated endovascular aneurism repair), in whom CSF drainage catheter was used, between January 2010 and March 2017. Collected data regarding demographic, perioperative patients characteristics, neurologic symptoms (NS) and other complications. All patients were submitted to general anesthesia (GA) as result of complexity and length of surgery. Known risk factors (RF) for SCI were taken into account. 19 patients, 89,5% (n=17) male, mean age of 66±9 years. 63,2% were classified as ASA III and 36,8% as ASA IV. 9 patients submitted to TEVAR (47,4%); the remaining were submitted to fEVAR. 73,7 % were programed procedures. There were intraoperative complications in 3 patients: iliac artery (IA) rupture in 2 patients, laceration of the axillary artery in 1 patient, all required surgical repair. All catheters were placed in awake patients, before GA induction, and were left in place 2,5 days. 7 patients needed drainage because of CSF pressure>10mmHg intra- or postoperatively. 3 patients developed early symptoms of SCI (decreased mobility and strength of legs). Complete recovery occurred in all patients, except one who recovered just partially. 1 patient developed late NS: paraparesia on 40th postoperative day (POD) as result of spinal stroke. 30 days mortality was 10,5% (n=2), due to cardiorespiratory arrest- 1 by hypovolemic shock (on 3rd POD), 1 by unknown cause (14th POD). This study was limited by the small sample size. CSF drainage catheter was an efficient measure in prevention and treatment of SCI in this sample, since there was no case of complications due to SCI. CSF drainage seems to be an effective technique in preventing SCI. Further studies are required to determine the effectiveness and compare the different methods available for the prevention of SCI complications.

Subglacial drainage patterns of Devon Island, Canada: detailed comparison of rivers and subglacial meltwater channels

NASA Astrophysics Data System (ADS)

Grau Galofre, Anna; Jellinek, A. Mark; Osinski, Gordon R.; Zanetti, Michael; Kukko, Antero

2018-04-01

Subglacial meltwater channels (N-channels) are attributed to erosion by meltwater in subglacial conduits. They exert a major control on meltwater accumulation at the base of ice sheets, serving as drainage pathways and modifying ice flow rates. The study of exposed relict subglacial channels offers a unique opportunity to characterize the geomorphologic fingerprint of subglacial erosion as well as study the structure and characteristics of ice sheet drainage systems. In this study we present detailed field and remote sensing observations of exposed subglacial meltwater channels in excellent preservation state on Devon Island (Canadian Arctic Archipelago). We characterize channel cross section, longitudinal profiles, and network morphologies and establish the spatial extent and distinctive characteristics of subglacial drainage systems. We use field-based GPS measurements of subglacial channel longitudinal profiles, along with stereo imagery-derived digital surface models (DSMs), and novel kinematic portable lidar data to establish a detailed characterization of subglacial channels in our field study area, including their distinction from rivers and other meltwater drainage systems. Subglacial channels typically cluster in groups of ˜ 10 channels and are oriented perpendicular to active or former ice margins. Although their overall direction generally follows topographic gradients, channels can be oblique to topographic gradients and have undulating longitudinal profiles. We also observe that the width of first-order tributaries is 1 to 2 orders of magnitude larger than in Devon Island river systems and approximately constant. Furthermore, our findings are consistent with theoretical expectations drawn from analyses of flow driven by gradients in effective water pressure related to variations in ice thickness. Our field and remote sensing observations represent the first high-resolution study of the subglacial geomorphology of the high Arctic, and provide quantitative and qualitative descriptions of subglacial channels that revisit well-established field identification guidelines. Distinguishing subglacial channels in topographic data is critical for understanding the emergence, geometry, and extent of channelized meltwater systems and their role in ice sheet drainage. The final aim of this study is to facilitate the identification of subglacial channel networks throughout the globe by using remote sensing techniques, which will improve the detection of these systems and help to build understanding of the underlying mechanics of subglacial channelized drainage.

The three R's of roads: redesign, reconstruction, and restoration

Treesearch

Lloyd W. Swift; Richard G. Burns

1999-01-01

All too often, unpaved forest access roads in the Southern Appalachian Mountains were located near streams and rivers, thereby contributing storm flow and sediment to the aquatic ecosystem.Landowners may not have the resources to reconstruct and relocate all these roads to protect water quality.However, simple techniques for redesign of storm water drainage structures...

COMPARISON OF DATA FROM SYNTHETIC LEACHATE AND DIRECT SAMPLING OF ACID DRAINAGE FROM MINE WASTES: IMPLICATIONS FOR MERCURY TRANSPORT AND WASTE MANAGEMENT

EPA Science Inventory

The Sulphur Bank Mercury Mine (SBMM) in Lake County, California operated from the 1860s through the 1950's. Mining for sulfur started with surface operations and progressed to shaft, then open pit techniques to obtain mercury. Mining has resulted in deposition of approximately ...

Cenozoic Source-to-Sink of the African margin of the Equatorial Atlantic

NASA Astrophysics Data System (ADS)

Rouby, Delphine; Chardon, Dominique; Huyghe, Damien; Guillocheau, François; Robin, Cecile; Loparev, Artiom; Ye, Jing; Dall'Asta, Massimo; Grimaud, Jean-Louis

2016-04-01

The objective of the Transform Source to Sink Project (TS2P) is to link the dynamics of the erosion of the West African Craton to the offshore sedimentary basins of the African margin of the Equatorial Atlantic at geological time scales. This margin, alternating transform and oblique segments from Guinea to Nigeria, shows a strong structural variability in the margin width, continental geology and relief, drainage networks and subsidence/accumulation patterns. We analyzed this system combining onshore geology and geomorphology as well as offshore sub-surface data. Mapping and regional correlation of dated lateritic paleo-landscape remnants allows us to reconstruct two physiographic configurations of West Africa during the Cenozoic. We corrected those reconstitutions from flexural isostasy related to the subsequent erosion. These geometries show that the present-day drainage organization stabilized by at least 29 Myrs ago (probably by 34 Myr) revealing the antiquity of the Senegambia, Niger and Volta catchments toward the Atlantic as well as of the marginal upwarp currently forming a continental divide. The drainage rearrangement that lead to this drainage organization was primarily enhanced by the topographic growth of the Hoggar swell and caused a major stratigraphic turnover along the Equatorial margin of West Africa. Elevation differences between paleo-landscape remnants give access to the spatial and temporal distribution of denudation for 3 time-increments since 45 Myrs. From this, we estimate the volumes of sediments and associated lithologies exported by the West African Craton toward different segments of the margin, taking into account the type of eroded bedrock and the successive drainage reorganizations. We compare these data to Cenozoic accumulation histories in the basins and discuss their stratigraphic expression according to the type of margin segment they are preserved in.

Does Fibrin Sealant Reduce Seroma after Immediate Breast Reconstruction Utilizing a Latissimus Dorsi Myocutaneous Flap?

PubMed Central

Cha, Han Gyu; Shin, Ho Seong; Kang, Moon Seok; Nam, Seung Min

2012-01-01

Background The most common complication of latissimus dorsi myocutaneous flap in breast reconstruction is seroma formation in the back. Many clinical studies have shown that fibrin sealant reduces seroma formation. We investigated any statistically significant differences in postoperative drainage and seroma formation when utilizing the fibrin sealant on the site of the latissimus dorsi myocutaneous flap harvested for immediate breast reconstruction after skin-sparing partial mastectomy. Methods A total of 46 patients underwent immediate breast reconstruction utilizing a latissimus dorsi myocutaneous island flap. Of those, 23 patients underwent the procedure without fibrin sealant and the other 23 were administered the fibrin sealant. All flaps were elevated with manual dissection by the same surgeon and were analyzed to evaluate the potential benefits of the fibrin sealant. The correlation analysis and Mann-Whitney U test were used for analyzing the drainage volume according to age, weight of the breast specimen, and body mass index. Results Although not statistically significant, the cumulative drainage fluid volume was higher in the control group until postoperative day 2 (530.1 mL compared to 502.3 mL), but the fibrin sealant group showed more drainage beginning on postoperative day 3. The donor site comparisons showed the fibrin sealant group had more drainage beginning on postoperative day 3 and the drain was removed 1 day earlier in the control group. Conclusions The use of fibrin sealant resulted in no reduction of seroma formation. Because the benefits of the fibrin sealant are not clear, the use of fibrin sealant must be fully discussed with patients before its use as a part of informed consent. PMID:23094246

Human amplified changes in precipitation-runoff patterns in large river basins of the Midwestern United States

NASA Astrophysics Data System (ADS)

Kelly, Sara A.; Takbiri, Zeinab; Belmont, Patrick; Foufoula-Georgiou, Efi

2017-10-01

Complete transformations of land cover from prairie, wetlands, and hardwood forests to row crop agriculture and urban centers are thought to have caused profound changes in hydrology in the Upper Midwestern US since the 1800s. In this study, we investigate four large (23 000-69 000 km2) Midwest river basins that span climate and land use gradients to understand how climate and agricultural drainage have influenced basin hydrology over the last 79 years. We use daily, monthly, and annual flow metrics to document streamflow changes and discuss those changes in the context of precipitation and land use changes. Since 1935, flow, precipitation, artificial drainage extent, and corn and soybean acreage have increased across the region. In extensively drained basins, we observe 2 to 4 fold increases in low flows and 1.5 to 3 fold increases in high and extreme flows. Using a water budget, we determined that the storage term has decreased in intensively drained and cultivated basins by 30-200 % since 1975, but increased by roughly 30 % in the less agricultural basin. Storage has generally decreased during spring and summer months and increased during fall and winter months in all watersheds. Thus, the loss of storage and enhanced hydrologic connectivity and efficiency imparted by artificial agricultural drainage appear to have amplified the streamflow response to precipitation increases in the Midwest. Future increases in precipitation are likely to further intensify drainage practices and increase streamflows. Increased streamflow has implications for flood risk, channel adjustment, and sediment and nutrient transport and presents unique challenges for agriculture and water resource management in the Midwest. Better documentation of existing and future drain tile and ditch installation is needed to further understand the role of climate versus drainage across multiple spatial and temporal scales.

Planetary geomorphology field studies: Washington and Alaska

NASA Technical Reports Server (NTRS)

Malin, M. C.

1984-01-01

Field studies of terrestrial landforms and the processes that shape them provide new directions to the study of planetary features. Investigations discussed address principally mudflow phenomena and drainage development. At the Valley of 10,000 Smokes (Katmai, AK) and Mount St. Helens, WA, studies of the development of erosional landforms (in particular, drainage) on fresh, new surfaces permitted analysis of the result of competition between geomorphic processes. Of specific interest is the development of stream pattern as a function of the competition between perennial seepage overland flow (from glacial or groundwater sources), ephemeral overland flow (from pluvial or seasonal melt sources), and ephemeral/perennial groundwater sapping, as a function of time since initial resurfacing, material properties, and seasonal/annual environmental conditions.

Conservation status of an imperiled crayfish, Faxonius marchandi Hobbs, 1948 (Decapoda: Cambaridae)

USGS Publications Warehouse

DiStefano, Robert J.; Magoulick, Daniel D.; Flinders, C.A.; Imhoff, Emily M.

2017-01-01

We summarize the distribution, ecology, threats, and conservation status of Faxonius marchandi (Hobbs, 1948), the Mammoth Spring crayfish, a limited-range endemic species to the Spring River drainage of Missouri and Arkansas, USA. The species is known from 51 locations on lower-order perennial and intermittent streams in only the eastern portion of the drainage. Faxonius marchandi is found in larger rocky substrates in shallower, slower-velocity habitats of well-buffered, mineral-rich streams. The invading alien crayfish Faxonius neglectus chaenodactylus (Williams, 1952) is the most likely threat to F. marchandi. These compiled data should serve as a baseline for future comparison, and facilitate discussion about future management, conservation, and research efforts.

Remotely sensed soil moisture input to a hydrologic model

NASA Technical Reports Server (NTRS)

Engman, E. T.; Kustas, W. P.; Wang, J. R.

1989-01-01

The possibility of using detailed spatial soil moisture maps as input to a runoff model was investigated. The water balance of a small drainage basin was simulated using a simple storage model. Aircraft microwave measurements of soil moisture were used to construct two-dimensional maps of the spatial distribution of the soil moisture. Data from overflights on different dates provided the temporal changes resulting from soil drainage and evapotranspiration. The study site and data collection are described, and the soil measurement data are given. The model selection is discussed, and the simulation results are summarized. It is concluded that a time series of soil moisture is a valuable new type of data for verifying model performance and for updating and correcting simulated streamflow.

Microbial communities, processes and functions in acid mine drainage ecosystems.

PubMed

Chen, Lin-xing; Huang, Li-nan; Méndez-García, Celia; Kuang, Jia-liang; Hua, Zheng-shuang; Liu, Jun; Shu, Wen-sheng

2016-04-01

Acid mine drainage (AMD) is generated from the oxidative dissolution of metal sulfides when water and oxygen are available largely due to human mining activities. This process can be accelerated by indigenous microorganisms. In the last several decades, culture-dependent researches have uncovered and validated the roles of AMD microorganisms in metal sulfides oxidation and acid generation processes, and culture-independent studies have largely revealed the diversity and metabolic potentials and activities of AMD communities, leading towards a full understanding of the microbial diversity, functions and interactions in AMD ecosystems. This review describes the diversity of microorganisms and their functions in AMD ecosystems, and discusses their biotechnological applications in biomining and AMD bioremediation according to their capabilities. Copyright © 2016 Elsevier Ltd. All rights reserved.

Flood Syndrome: Spontaneous Umbilical Hernia Rupture Leaking Ascitic Fluid—A Case Report

PubMed Central

Nguyen, Emilie T; Tudtud-Hans, Leah A

2017-01-01

Introduction We report a rare case of Flood syndrome, which is a spontaneous rupture of an umbilical hernia. Case Presentation A 42-year-old man with decompensated hepatitis C and alcoholic cirrhosis complicated by ascites and esophageal varices presented with 1 day of ascitic fluid drainage after rupture of a preexisting umbilical hernia associated with diffuse abdominal pain and tenderness. A pigtail drain was placed in the right upper abdominal quadrant to decrease fluid drainage from the abdominal wall defect, allowing it to heal naturally. Discussion The spontaneous rupture of an umbilical hernia in our patient highlights a rare complication with high mortality rates and stresses the challenge of treatment that falls in the area between medical and surgical management. PMID:28678688

The impact of suction drainage on orbital compartment syndrome after craniofacial surgery.

PubMed

Fenzl, Carlton R; Golio, Dominick

2014-07-01

Postoperative orbital compartment syndrome is a potentially blinding complication of surgery in the orbital region. We describe the technique of orbital drain placement as a method of preventing vision loss resulting from orbital compartment syndrome. We present a retrospective case series of 29 patients who underwent orbital fracture, facial fracture, and orbital implant removal from 7/4/2008 to 5/3/2013 by the same craniofacial surgeon. An orbital drain was placed in each patient. The drainage was recorded daily until drain removal. Criteria for removal included less than or equal to 5 mL of drainage in 24 hours. Of the 29 patients included in this study, 21 were men and 8 were women. Ages ranged from 17 to 67 years. The postoperative drainage ranged from less than 1 mL to 71 mL of serosanguinous fluid. All drains were removed between the first and sixth postoperative days. No postoperative visual loss, infections, or additional antibiotics were recorded with follow-up reaching as far as 40 months. Postoperative orbital compartment syndrome is a dangerous complication of surgery in the orbital region. Its rapid onset necessitates immediate intervention to prevent permanent vision loss. Morphologic changes to the optic nerve as well as reductions in electroretinogram a- and b-wave amplitudes have been demonstrated with as little as 7 mL of fluid accumulation. Intraoperative orbital drain placement should be considered in all patients undergoing surgery in the orbital region as a preventative measure.

A spatial ecology study on the effects of field conditions and crop rotation on the incidence of Plectris aliena (Coleoptera: Scarabaeidae) grub damage to sweetpotato roots.

PubMed

Brill, Nancy L; Osborne, Jason; Abney, Mark R

2013-10-01

A farmscape study was conducted in commercial sweetpotato (Ipomoea batatas (L.) Lam) fields in Columbus County, NC, in 2010 and 2011 to investigate the effects of the following field conditions: soil drainage class, soil texture, field size, border habitat, land elevation, and the previous year's crop rotation on the incidence of damage caused by Plectris aliena Chapman (Coleoptera:Scarabaeidae) larval feeding. Soil drainage and crop rotation significantly affected the incidence of damage to roots, with well drained soils having a low estimated incidence of damaged roots (0.004) compared with all other drainage classes (0.009-0.011 incidence of damaged roots). Fields with soybeans [Glycine max (L.) Merr] planted the preceding year had the highest incidence of root damage (0.15) compared with all other crops. The effects of border habitats, which were adjacent to grower fields where roots were sampled, showed that as the location of the roots was closer to borders of soybean (planted the year before) or grass fields, the chance of damage to roots decreased. Results indicate that growers can use crop rotation as a management technique and avoid planting sweetpotatoes the year after soybeans to reduce the incidence of P. aliena larval feeding on sweetpotato roots. Environmental conditions such as fields with poor drainage and certain border habitats may be avoided, or selected, by growers to reduce risk of damage to roots by P. aliena.

Presacral abscess as a rare complication of sacral nerve stimulator implantation.

PubMed

Gumber, A; Ayyar, S; Varia, H; Pettit, S

2017-03-01

A 50-year-old man with intractable anal pain attributed to proctalgia fugax underwent insertion of a sacral nerve stimulator via the right S3 vertebral foramen for pain control with good symptomatic relief. Thirteen months later, he presented with signs of sepsis. Computed tomography (CT) and magnetic resonance imaging (MRI) showed a large presacral abscess. MRI demonstrated increased enhancement along the pathway of the stimulator electrode, indicating that the abscess was caused by infection introduced at the time of sacral nerve stimulator placement. The patient was treated with broad spectrum antibiotics, and the sacral nerve stimulator and electrode were removed. Attempts were made to drain the abscess transrectally using minimally invasive techniques but these were unsuccessful and CT guided transperineal drainage was then performed. Despite this, the presacral abscess progressed, developing enlarging gas locules and extending to the pelvic brim to involve the aortic bifurcation, causing hydronephrosis and radiological signs of impending sacral osteomyelitis. MRI showed communication between the rectum and abscess resulting from transrectal drainage. In view of the progressive presacral sepsis, a laparotomy was performed with drainage of the abscess, closure of the upper rectum and formation of a defunctioning end sigmoid colostomy. Following this, the presacral infection resolved. Presacral abscess formation secondary to an infected sacral nerve stimulator electrode has not been reported previously. Our experience suggests that in a similar situation, the optimal management is to perform laparotomy with drainage of the presacral abscess together with simultaneous removal of the sacral nerve stimulator and electrode.

Presacral abscess as a rare complication of sacral nerve stimulator implantation

PubMed Central

Gumber, A; Ayyar, S; Varia, H

2017-01-01

A 50-year-old man with intractable anal pain attributed to proctalgia fugax underwent insertion of a sacral nerve stimulator via the right S3 vertebral foramen for pain control with good symptomatic relief. Thirteen months later, he presented with signs of sepsis. Computed tomography (CT) and magnetic resonance imaging (MRI) showed a large presacral abscess. MRI demonstrated increased enhancement along the pathway of the stimulator electrode, indicating that the abscess was caused by infection introduced at the time of sacral nerve stimulator placement. The patient was treated with broad spectrum antibiotics, and the sacral nerve stimulator and electrode were removed. Attempts were made to drain the abscess transrectally using minimally invasive techniques but these were unsuccessful and CT guided transperineal drainage was then performed. Despite this, the presacral abscess progressed, developing enlarging gas locules and extending to the pelvic brim to involve the aortic bifurcation, causing hydronephrosis and radiological signs of impending sacral osteomyelitis. MRI showed communication between the rectum and abscess resulting from transrectal drainage. In view of the progressive presacral sepsis, a laparotomy was performed with drainage of the abscess, closure of the upper rectum and formation of a defunctioning end sigmoid colostomy. Following this, the presacral infection resolved. Presacral abscess formation secondary to an infected sacral nerve stimulator electrode has not been reported previously. Our experience suggests that in a similar situation, the optimal management is to perform laparotomy with drainage of the presacral abscess together with simultaneous removal of the sacral nerve stimulator and electrode. PMID:28071947

[A Paired Case Controlled Study Comparing the Short-term Outcomes of Da Vinci RATS and VATS Approach for Non-small Cell Lung Cancer].

PubMed

Dai, Feng; Xu, Shiguang; Xu, Wei; Ding, Renquan; Liu, Bo; Meng, Hao; Kang, Yunteng; Meng, Xiangrui; Lin, Jie; Wang, Shumin

2018-03-20

Da Vinci Surgical System is one of the greatest inventions of the 20th century, which represents the development direction of the precise minimally invasive surgical techniques, the aim of this study was to comparing the short-term outcomes between da Vinci robot-assisted lobectomy and video-assisted thoracic surgery (VATS) lobectomy for non-small cell lung cancer. 45 pairs of non-small cell lung cancer patients underwent pulmonary lobectomy with da Vinci Robotic assisted thoracoscopic (RATS) and VATS approach during the same period from January 2014 to January 2017. The operative time, estimated blood loss (EBL), total number and total groups of dissected lymph nodes, postoperative duration of drainage, the first day volume of drainage, total volume of drainage were compared. No perioperative death and convertion to thoracotomy occured in both groups. There were significant difference between RATS group and VATS group in EBL [(50.30±32.33) mL vs (208.60±132.63) mL], the first day volume of drainage [(275.00±145.42) mL vs (347.60±125.80) mL], the dissected total number [(22.67±9.67) vs (15.51±5.41)] and total team [(6.31±1.43) vs (4.91±1.04)] of lymph node. There were no significant difference in other outcomes. RATS is safe and effective and took better short-outcomes than VATS in non-small cell lung cancer.

Effective photodynamic therapy against microbial populations in human deep tissue abscess aspirates

PubMed Central

Haidaris, Constantine G.; Foster, Thomas H.; Waldman, David L.; Mathes, Edward J.; McNamara, JoAnne; Curran, Timothy

2014-01-01

Background and Objective The primary therapy for deep tissue abscesses is drainage accompanied by systemic antimicrobial treatment. However, the long antibiotic course required increases the probability of acquired resistance, and the high incidence of polymicrobial infections in abscesses complicates treatment choices. Photodynamic therapy (PDT) is effective against multiple classes of organisms, including those displaying drug resistance, and may serve as a useful adjunct to the standard of care by reduction of abscess microbial burden following drainage. Study Design/Materials and Methods Aspirates were obtained from 32 patients who underwent image-guided percutaneous drainage of the abscess cavity. The majority of the specimens (24/32) were abdominal, with the remainder from liver and lung. Conventional microbiological techniques and nucleotide sequence analysis of rRNA gene fragments were used to characterize microbial populations from abscess aspirates. We evaluated the sensitivity of microorganisms to methylene blue-sensitized PDT in vitro both within the context of an abscess aspirate and as individual isolates. Results Most isolates were bacterial, with the fungus Candida tropicalis also isolated from two specimens. We examined the sensitivity of these microorganisms to methylene blue-PDT. Complete elimination of culturable microorganisms was achieved in three different aspirates, and significant killing (p < 0.0001) was observed in all individual microbial isolates tested compared to controls. Conclusions These results and the technical feasibility of advancing optical fibers through catheters at the time of drainage motivate further work on including PDT as a therapeutic option during abscess treatment. PMID:23996629

Effective photodynamic therapy against microbial populations in human deep tissue abscess aspirates.

PubMed

Haidaris, Constantine G; Foster, Thomas H; Waldman, David L; Mathes, Edward J; McNamara, Joanne; Curran, Timothy

2013-10-01

The primary therapy for deep tissue abscesses is drainage accompanied by systemic antimicrobial treatment. However, the long antibiotic course required increases the probability of acquired resistance, and the high incidence of polymicrobial infections in abscesses complicates treatment choices. Photodynamic therapy (PDT) is effective against multiple classes of organisms, including those displaying drug resistance, and may serve as a useful adjunct to the standard of care by reduction of abscess microbial burden following drainage. Aspirates were obtained from 32 patients who underwent image-guided percutaneous drainage of the abscess cavity. The majority of the specimens (24/32) were abdominal, with the remainder from liver and lung. Conventional microbiological techniques and nucleotide sequence analysis of rRNA gene fragments were used to characterize microbial populations from abscess aspirates. We evaluated the sensitivity of microorganisms to methylene blue-sensitized PDT in vitro both within the context of an abscess aspirate and as individual isolates. Most isolates were bacterial, with the fungus Candida tropicalis also isolated from two specimens. We examined the sensitivity of these microorganisms to methylene blue-PDT. Complete elimination of culturable microorganisms was achieved in three different aspirates, and significant killing (P < 0.0001) was observed in all individual microbial isolates tested compared to controls. These results and the technical feasibility of advancing optical fibers through catheters at the time of drainage motivate further work on including PDT as a therapeutic option during abscess treatment. © 2013 Wiley Periodicals, Inc.

Winery wastewater treatment using the land filter technique.

PubMed

Christen, E W; Quayle, W C; Marcoux, M A; Arienzo, M; Jayawardane, N S

2010-08-01

This study outlines a new approach to the treatment of winery wastewater by application to a land FILTER (Filtration and Irrigated cropping for Land Treatment and Effluent Reuse) system. The land FILTER system was tested at a medium size rural winery crushing approximately 20,000 tonnes of grapes. The approach consisted of a preliminary treatment through a coarse screening and settling in treatment ponds, followed by application to the land FILTER planted to pasture. The land FILTER system efficiently dealt with variable volumes and nutrient loads in the wastewater. It was operated to minimize pollutant loads in the treated water (subsurface drainage) and provide adequate leaching to manage salt in the soil profile. The land FILTER system was effective in neutralizing the pH of the wastewater and removing nutrient pollutants to meet EPA discharge limits. However, suspended solids (SS) and biological oxygen demand (BOD) levels in the subsurface drainage waters slightly exceeded EPA limits for discharge. The high organic content in the wastewater initially caused some soil blockage and impeded drainage in the land FILTER site. This was addressed by reducing the hydraulic loading rate to allow increased soil drying between wastewater irrigations. The analysis of soil characteristics after the application of wastewater found that there was some potassium accumulation in the profile but sodium and nutrients decreased after wastewater application. Thus, the wastewater application and provision of subsurface drainage ensured adequate leaching, and so was adequate to avoid the risk of soil salinisation. Crown Copyright 2010. Published by Elsevier Ltd. All rights reserved.

Atlas of Ohio Aquatic Insects: Volume II, Plecoptera

PubMed Central

Grubbs, Scott A.; Armitage, Brian J.; Baumann, Richard W.; Clark, Shawn M.; Bolton, Michael J.

2016-01-01

Abstract Background We provide volume II of a distributional atlas of aquatic insects for the eastern USA state of Ohio. This treatment of stoneflies (Plecoptera) is companion to Armitage et al. (2011) on caddisflies (Trichoptera). We build on a recent analysis of Ohio stonefly diversity patterns based on large drainages (DeWalt et al. 2012), but add 3717 new records to the data set. We base most analyses on the United States Geological Survey Hierarchical Unit Code eight (HUC8) drainage scale. In addition to distributional maps for each species, we provide analyses of species richness versus HUC8 drainage area and the number of unique locations in a HUC8 drainage, species richness versus Ohio counties, analyze adult presence phenology throughout the year, and demonstrate stream size range affiliation for each species. New information This work is based on a total of 7797 specimen records gathered from 21 regional museums, agency data, personal collections, and from the literature Table 1. To our knowledge this is the largest stonefly data set available for a similarly sized geopolitical area anywhere in the world. These data are made available as a Darwin Core Archive supported by the Pensoft Integrated Publishing Toolkit (DeWalt et al. 2016b). All known published papers reporting stoneflies from Ohio are detailed in Suppl. material 1. We recovered 102 species from Ohio, including all nine Nearctic families Table 2​. Two species were removed from the DeWalt et al. (2012) list and two new state records added. Perlidae (32 spp.) was most speciose, compared to the low diversity Pteronarcyidae (2 spp.) and Peltoperlidae (1 sp.). The richest HUC8 drainages occurred in northeastern, south-central, and southern regions of the state where drainages were heavily forested, had the highest slopes, and were contained within or adjacent to the unglaciated Allegheny and Appalachian Plateaus. Species poor drainages occurred mainly in the northwestern region where Wisconsinan aged lake plains climaxed to an expansive wooded wetland, the Black Swamp. The unglaciated Lower Scioto drainage (72 spp.) in south-central Ohio supported the greatest species richness. There was no relationship between species richness and HUC8 drainage size, but the number of unique locations in a drainage strongly related to species richness. All Ohio counties were represented in the data set with Hocking County (59 spp.) of the Lower Scioto drainage being the richest and most heavily sampled. Adult presence phenology was influenced by phylogenetic relationships such that the superfamily Nemouroidea (Capniidae, Leuctridae, Nemouridae, and Taeniopterygidae) generally emerged in winter and spring while the superfamilies Pteronarcyoidea (Pteronarcyidae, Peltoperlidae) and Perloidea (Chloroperlidae, Perlidae, Perlodidae) emerged later, some species continuing emergence through summer months. Species often occupied specific stream size ranges, while others were generalists. Two species once histrorically abundant in the western Lake Erie Bass Islands no longer reside there. Each of the 102 species is discussed in detail, including several that require additional collecting efforts to confirm their identities, presence, and distribution in Ohio. PMID:27932932

[What is and who created chiropractic massage?].

PubMed

Sagrera Ferrándiz, J

2003-01-01

Even though many massage techniques are called chiromassage, this term must be used to describe a technique created by its inventor, Dr. Ferrándiz, who based on knowledge from German, Swiss and Oriental techniques, developed his own technique and in order to differentiate it from other techniques, gave it the name chiro-meaning hand-massage; which is to say massage using hands, without the use of any apparatus. Once this clarification has been made, the author analyzes the parts which compose a good chiromassage: 1) preparatory exercises: exploration, initial contact, magnetic sedative passes, etc. 2) kneading: in order to distort and elongate muscle fibers, 3) specific exercises: distinct one for each individual case, and 4) finalizing exercises: vibrations, drumming with one's fingers, venal drainage and magnetic sedative passes.

Report on Physics of Channelization: Theory, Experiment, and Observation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kudrolli, Arshad

2014-05-19

The project involved a study of physical processes that create eroded channel and drainage networks. A particular focus was on how the shape of the channels and the network depended on the nature of the fluid flow. Our approach was to combine theoretical, experimental, and observational studies in close collaboration with Professor Daniel Rothman of the Massachusetts Institute of Technology. Laboratory -scaled experiments were developed and quantitative data on the shape of the pattern and erosion dynamics are obtained with a laser-aided topography technique and fluorescent optical imaging techniques.

Hydrological Modeling of Rainfall-Watershed-Bioretention System with EPA SWMM

NASA Astrophysics Data System (ADS)

gülbaz, sezar; melek kazezyılmaz-alhan, cevza

2016-04-01

Water resources should be protected for the sustainability of water supply and water quality. Human activities such as high urbanization with lack of infrastructure system and uncontrolled agricultural facilities adversely affect the water resources. Therefore, recent techniques should be investigated in detail to avoid present and future problems like flood, drought and water pollution. Low Impact Development-Best Management Practice (LID-BMP) is such a technique to manage storm water runoff and quality. There are several LID storm water BMPs such as bioretention facilities, rain gardens, storm water wetlands, vegetated rooftops, rain barrels, vegetative swales and permeable pavements. Bioretention is a type of Low Impact Developments (LIDs) implemented to diminish adverse effects of urbanization by reducing peak flows over the surface and improving surface water quality simultaneously. Different soil types in different ratios are considered in bioretention design which affects the performance of bioretention systems. Therefore, in this study, a hydrologic model for bioretention is developed by using Environmental Protection Agency Storm Water Management Model (EPA SWMM). Part of the input data is supplied to the hydrologic model by experimental setup called Rainfall-Watershed-Bioretention (RWB). RWB System is developed to investigate the relation among rainfall, watershed and bioretention. This setup consists of three main parts which are artificial rainfall system, drainage area and four bioretention columns with different soil mixture. EPA SWMM is a dynamic simulation model for the surface runoff which develops on a watershed during a rainfall event. The model is commonly used to plan, analyze, and control storm water runoff, to design drainage system components and to evaluate watershed management of both urban and rural areas. Furthermore, EPA SWMM is a well-known program to model LID-Bioretention in the literature. Therefore, EPA SWMM is employed in drainage and bioretention modeling. Calibration of hydrologic model is made using part of the measured data in RWB System for drainage area and for each bioretention column separately. Finally, performance of the model is evaluated by comparing the model results with the experimental data collected in RWB system.

The Role of County Surveyors and County Drainage Boards in Addressing Water Quality.

PubMed

Dunn, Mike; Mullendore, Nathan; de Jalon, Silvestre Garcia; Prokopy, Linda Stalker

2016-06-01

Water quality problems stemming from the Midwestern U.S. agricultural landscape have been widely recognized and documented. The Midwestern state of Indiana contains tens of thousands of miles of regulated drains that represent biotic communities that comprise the headwaters of the state's many rivers and creeks. Traditional management, however, reduces these waterways to their most basic function as conveyances, ignoring their role in the ecosystem as hosts for biotic and abiotic processes that actively regulate the fate and transport of nutrients and farm chemicals. Novel techniques and practices such as the two-stage ditch, denitrifying bioreactor, and constructed wetlands represent promising alternatives to traditional management approaches, yet many of these tools remain underutilized. To date, conservation efforts and research have focused on increasing the voluntary adoption of practices among agricultural producers. Comparatively little attention has been paid to the roles of the drainage professionals responsible for the management of waterways and regulated drains. To address this gap, we draw on survey responses from 39 county surveyors and 85 drainage board members operating in Indiana. By examining the backgrounds, attitudes, and actions of these individuals, we consider their role in advocating and implementing novel conservation practices.

Flood hazard studies in Central Texas using orbital and suborbital remote sensing machinery

NASA Technical Reports Server (NTRS)

Baker, V. R.; Holz, R. K.; Patton, P. C.

1975-01-01

Central Texas is subject to infrequent, unusually intense rainstorms which cause extremely rapid runoff from drainage basins developed on the deeply dissected limestone and marl bedrock of the Edwards Plateau. One approach to flood hazard evaluation in this area is a parametric model relating flood hydrograph characteristics to quantitative geomorphic properties of the drainage basins. The preliminary model uses multiple regression techniques to predict potential peak flood discharge from basin magnitude, drainage density, and ruggedness number. After mapping small catchment networks from remote sensing imagery, input data for the model are generated by network digitization and analysis by a computer assisted routine of watershed analysis. The study evaluated the network resolution capabilities of the following data formats: (1) large-scale (1:24,000) topographic maps, employing Strahler's "method of v's," (2) standard low altitude black and white aerial photography (1:13,000 and 1:20,000 scales), (3) NASA - generated aerial infrared photography at scales ranging from 1:48,000 to 1:123,000, and (4) Skylab Earth Resources Experiment Package S-190A and S-190B sensors (1:750,000 and 1:500,000 respectively).

Treatment of long ureteric strictures with buccal mucosal grafts.

PubMed

Kroepfl, Darko; Loewen, Heinrich; Klevecka, Virgilijus; Musch, Michael

2010-05-01

To describe the reconstruction of long ureteric strictures using buccal mucosal patch grafts and to report the intermediate-term functional outcome. Between November 2000 and October 2006 reconstruction of seven long ureteric strictures using buccal mucosal patch grafts and omental wrapping was performed in five women (one with bilateral strictures) and one man. The surgical steps of stricture reconstruction and wrapping with omentum are described in detail. Stricture recurrence was defined as persistent impaired ureteric drainage as displayed by imaging techniques or the necessity to prolong JJ stenting. Patency rates and stricture recurrence-free survival rates are provided. With a median follow up of 18 months five of the seven strictures were recurrence-free. Graft take was good in all patients. In one asymptomatic patient, there was impaired ureteric drainage on the reconstructed side, and in one patient with reconstruction of both ureters prolonged JJ stenting of one side was necessary. In both patients, the impaired drainage was caused by persistent stricture below the reconstructed ureteric segments. At intermediate-term follow-up in a small group of patients with long ureteric strictures, treatment with buccal mucosal patch grafts and omental wrapping showed good functional outcome.

Fly Ash as a Time Marker for Anthropocene Alluvial Sedimentation

NASA Astrophysics Data System (ADS)

Bettis, E. A., III; Grimley, D. A.; Anders, A. M.; Bates, B.; Hannan, E.

2014-12-01

Human land use has transformed the landscapes, ecosystems and hydrology of the North American Midcontinent. One widespread impact of this transformation is increased runoff and accelerated soil erosion, which, along with direct human channel modifications and artificial drainage, have dramatically altered hydrologic and ecological conditions in streams and rivers with far-reaching results. A legacy of this change in streams and rivers is preserved on floodplains throughout the region in sediment known as post-settlement alluvium (PSA). Documenting the spatial and temporal pattern of historic floodplain sedimentation in the drainage network is part of a larger effort to understand decadal and century-scale sediment routing through the drainage system and the role of floodplain sedimentation in carbon sequestration. Fly ash, a product of high-temperature coal combustion, began to accumulate on the landscape in the early historic period (c.a.1840-1850 in Iowa and Illinois) as coal-burning technology such as steam engines came into use after 1850; prior to which no source of fly ash was present. Release of fly ash from coal burning in power plants and steam locomotives likely peaked in the early-mid 20th century. Fly ash particles (~ 1 to 10 % magnetic) are identified by their spheroidal shape and range in size from coarse clay to silt (~1-63µ). By identifying the percentage of fly ash spheroids in the magnetic separate (10 - 60µ size range) of a soil or sediment profile, the pre-fly ash Historic surface could be discerned. Application of this technique in selected localities in eastern Iowa (Clear Creek drainage) and central Illinois (Sangamon River drainage) resulted in successful demarcation of the PSA contact in areas where the boundary was physically evident. Bolstered by this success we were able to confidently demark the PSA contact in other settings where the boundary was not as physically evident. This relatively easy to implement, inexpensive tool will provide us with critical ground truth data for understanding long-term sediment movement through drainage basins and for modelling landscape evolution during the Anthropocene.

Techniques for estimating monthly mean streamflow at gaged sites and monthly streamflow duration characteristics at ungaged sites in central Nevada

USGS Publications Warehouse

Hess, G.W.; Bohman, L.R.

1996-01-01

Techniques for estimating monthly mean streamflow at gaged sites and monthly streamflow duration characteristics at ungaged sites in central Nevada were developed using streamflow records at six gaged sites and basin physical and climatic characteristics. Streamflow data at gaged sites were related by regression techniques to concurrent flows at nearby gaging stations so that monthly mean streamflows for periods of missing or no record can be estimated for gaged sites in central Nevada. The standard error of estimate for relations at these sites ranged from 12 to 196 percent. Also, monthly streamflow data for selected percent exceedence levels were used in regression analyses with basin and climatic variables to determine relations for ungaged basins for annual and monthly percent exceedence levels. Analyses indicate that the drainage area and percent of drainage area at altitudes greater than 10,000 feet are the most significant variables. For the annual percent exceedence, the standard error of estimate of the relations for ungaged sites ranged from 51 to 96 percent and standard error of prediction for ungaged sites ranged from 96 to 249 percent. For the monthly percent exceedence values, the standard error of estimate of the relations ranged from 31 to 168 percent, and the standard error of prediction ranged from 115 to 3,124 percent. Reliability and limitations of the estimating methods are described.

Replantation of an avulsed ear, using a single arterial anastamosis.

PubMed

O'Toole, G; Bhatti, K; Masood, S

2008-01-01

Avulsion of the ear is relatively uncommon and replantation a technical challenge. A case in which an avulsed ear was successfully replanted using a single arterial anastamosis is described. The surgical difficulties encountered, the pharmaceutical approach to postoperative care and the problems which resulted from the lack of venous drainage are discussed.

Airfield construction (3rd revised and enlarged edition)

NASA Astrophysics Data System (ADS)

Goretskii, Leonid I.; Boguslavskii, Adol'f. M.; Serebrenikov, Vadim A.; Barzdo, V. I.; Leshchitskaia, T. P.; Polosin-Nikitin, S. M.

The principal engineering aspects of airfield construction are discussed. In particular, attention is given to the fundamental principles and organizational aspects of airfield construction; excavation work and airfield layout; construction of drainage systems; foundations and pavements; and quality control and safety engineering. The discussion also covers the operation of various support plants, including concrete production and mixing, production of asphalt-concrete mixtures and organic binders, production of structural steel and reinforced concrete components, and operation of stone quarries and gravel pits.

Active Distribute Temperature Sensing to Estimate Vertical Water Content Variations in a Loamy-Sandy Soil

NASA Astrophysics Data System (ADS)

Ciocca, F.; Van De Giesen, N.; Assouline, S.; Huwald, H.; Hopmans, J. W.; Lunati, I.; Parlange, M. B.

2011-12-01

Optical fibers in combination with Raman scattering measurements (Distributed Temperature Sensor: DTS) have recently become more standard for the measurement of soil temperature. A recently developed technique to measure soil moisture called Active DTS (ADTS) is investigated in this study. ADTS consists of an application of a heat pulse for a fixed duration and power along the metal sheath covering the optical fiber placed in the soil. Soil moisture can be inferred from the increased temperature measured during the heating phase and the subsequent temperature decrease during the cooling phase. We assess this technique for a loamy-sandy soil as part of a field campaign that took place during the 2011 summer at EPFL. The measurements were taken within a weighing lysimeter (2.5 m depth and 1.2 m diameter) using an optical fiber arranged in 15 loops for a total measurement length of 52 m in the top 80 cm of the soil profile. Local soil moistures were simultaneously measured using capacity-based probes. Thermocouples, wrapped around the fiber, are used to account for the effects of the insulating cover surrounding the cable. Heat pulses of various duration and power have been applied for a range of soil moistures. Measurements were taken during periods of drainage and evaporation. The accuracy of the technique for the EPFL 2011 field campaign and the experiment are discussed and the soil moisture measurements are presented.

Towards a delimitation of southwestern Nigeria into hydrological regions

NASA Astrophysics Data System (ADS)

Ogunkoya, O. O.

1988-05-01

Fifteen third-order drainage basins (1:50,000) on the Basement Complex rocks of southwestern Nigeria are classified into hydrological regions using hydrologic response parameters of average daily mean specific discharge ( QA); daily mean specific discharges equalled or exceeded 90% ( Q90), 50% ( Q50) and 10% ( Q10) of the study period; variability index of flow ( VI); recession constant ( K) of flow from peak discharge at the end of the rainy season to minimum discharge in the dry season; total annual runoff ( RO); total runoff within the dry season ( DSRO); dry season runoff as a percentage of total annual runoff (% DSRO); runoff coefficient ( ROC); and, number of days during the study period when there was no flow ( NFD). An ordination technique and a classification algorithm derived from cluster analysis technique and incorporating the analysis of variance (ANOVA) tests to determine the level of significance of the homogeneity of derived classes, were used to classify the fifteen basins into five hydrologically homogeneous regions. The constituent basins of each region were observed to share common basin geology. It was observed that those drainage basins having at least 50% of their basin area underlain by quartzitic rocks form two groups and have the most desirable or optimal hydrologic response patterns, desirability or optimality being in terms of ability to potentially meet water resource development requirements (i.e. high perennial discharge, low variability and large groundwater contribution to stream flow). The basins predominantly underlain by granite-gneisses and amphibolitic rocks have much poorer hydrologic response patterns. Hydrological regionalization in southwestern Nigeria appears to be influenced by drainage basin geology while percentage area of the basin underlain by massive quartzites could be used as an index of occurrence of desirable hydrologic response pattern.

Outcomes of fornix-based versus limbus-based conjunctival incisions for glaucoma drainage device implant.

PubMed

Suhr, Abraham W; Lim, Michele C; Brandt, James D; Izquierdo, Juan Carlos; Willits, Neil

2012-01-01

To determine the effect of conjunctival incision location on the long-term efficacy of nonvalved glaucoma drainage devices. We conducted a retrospective review of patients ≥18 years of age with uncontrolled glaucoma [intraocular pressure (IOP) ≥18 mm Hg] who underwent glaucoma drainage device implantation. A comparison was made of a limbal-based (LB-BGI) versus fornix-based (FB-BGI) conjunctival flap during placement of a 350-mm Baerveldt glaucoma implant (AMO, Santa Ana, CA) in subjects with at least 1 year of follow-up data. The primary outcome measure was IOP; secondary outcome measures were medication burden, visual acuity, and surgical complications. One hundred sixty eyes of 147 glaucoma patients were included. Two years after surgery, the IOP in the LB-BGI group was 14.3±5.3 mm Hg and in the FB-BGI group 13.1±4.7 mm Hg (P=0.47). Overall success of IOP control was achieved at the final visit (range 1 to 5 y) in 90% of the LB-BGI group and 87% of the FB-BGI group (P=0.63). The medication burden of the 2 groups at 1 and 2 years after surgery was not statistically significantly different. Worsening of visual acuity by more than 2 lines was not statistically different between the groups 2 years after the surgery and at the final visit (P=0.47, P=0.60, respectively). A greater number of eyes developed endophthalmitis and were more likely to undergo subsequent tube revision in the FB-BGI group, but the differences were not significant. Both incision techniques were equally effective in controlling IOP. Each surgical approach has its advantages and this study suggests that either technique may be used safely and effectively.

Time-Integrated Monitoring of Dioxin-Like Polychlorinated Biphenyls (dl-PCBs) in Aquatic Environments using the Ceramic Toximeter and the CALUX Bioassay

PubMed Central

Addeck, Amr; Croes, Kim; Van Langenhove, Kersten; Denison, Michael S.; Afify, Ahmed S.; Gao, Yue; Elskens, Marc; Baeyens, Willy

2015-01-01

Ceramic passive samplers or toximeters (packed with active carbon 1% w/w on celite), in combination with the CALUX bioassay have been used as a time-integrated monitoring technique for dissolved dioxin-like PCBs in urban and industrial wastewaters. The technique showed to be reliable during laboratory experiments: (1) PCB-126 amounts extracted from the passive samplers increased linearly with the time of exposure and (2) PCB-126 concentrations calculated from the amounts accumulated by the passive samplers were in agreement with their concentrations in the testing solution. Afterwards the toximeters were applied in the field. Two sampling sites located in Egypt were chosen: the Belbeis drainage canal, and the EMAK paper mill. A total of 18 ceramic toximeters were exposed to the wastewater in both sampling sites for a maximum period of 4 weeks. Two samplers were collected weekly from each site to monitor the increase in target analytes over time. Extracts were analyzed using the CALUX bioassay and the total dioxin-like PCB toxicity was reported for the aqueous phase (water column), as well as the solid phase (sediment and sludge) in both sampling sites. The time-weighted average concentration (TWA) of dl-PCBs in wastewater of the paper mill during the sampling period ranged between 7.1 and 9.1 pg-BEQ L-1, while that of the drainage canal ranged between 9.5 and 12.2 pg-BEQ L-1. The dl-PCBs in the fibrous sludge (paper mill) and bottom sediment (drainage canal) were 0.5 and 0.4 pg-BEQ g-1 dry-weight, respectively. The organic-carbon normalized partition coefficients between sediment and water (log Koc) for the paper mill and the canal were 2.4 and 4.3, respectively. PMID:24468390

StreamStats in Oklahoma - Drainage-Basin Characteristics and Peak-Flow Frequency Statistics for Ungaged Streams

USGS Publications Warehouse

Smith, S. Jerrod; Esralew, Rachel A.

2010-01-01

The USGS Streamflow Statistics (StreamStats) Program was created to make geographic information systems-based estimation of streamflow statistics easier, faster, and more consistent than previously used manual techniques. The StreamStats user interface is a map-based internet application that allows users to easily obtain streamflow statistics, basin characteristics, and other information for user-selected U.S. Geological Survey data-collection stations and ungaged sites of interest. The application relies on the data collected at U.S. Geological Survey streamflow-gaging stations, computer aided computations of drainage-basin characteristics, and published regression equations for several geographic regions comprising the United States. The StreamStats application interface allows the user to (1) obtain information on features in selected map layers, (2) delineate drainage basins for ungaged sites, (3) download drainage-basin polygons to a shapefile, (4) compute selected basin characteristics for delineated drainage basins, (5) estimate selected streamflow statistics for ungaged points on a stream, (6) print map views, (7) retrieve information for U.S. Geological Survey streamflow-gaging stations, and (8) get help on using StreamStats. StreamStats was designed for national application, with each state, territory, or group of states responsible for creating unique geospatial datasets and regression equations to compute selected streamflow statistics. With the cooperation of the Oklahoma Department of Transportation, StreamStats has been implemented for Oklahoma and is available at http://water.usgs.gov/osw/streamstats/. The Oklahoma StreamStats application covers 69 processed hydrologic units and most of the state of Oklahoma. Basin characteristics available for computation include contributing drainage area, contributing drainage area that is unregulated by Natural Resources Conservation Service floodwater retarding structures, mean-annual precipitation at the drainage-basin outlet for the period 1961-1990, 10-85 channel slope (slope between points located at 10 percent and 85 percent of the longest flow-path length upstream from the outlet), and percent impervious area. The Oklahoma StreamStats application interacts with the National Streamflow Statistics database, which contains the peak-flow regression equations in a previously published report. Fourteen peak-flow (flood) frequency statistics are available for computation in the Oklahoma StreamStats application. These statistics include the peak flow at 2-, 5-, 10-, 25-, 50-, 100-, and 500-year recurrence intervals for rural, unregulated streams; and the peak flow at 2-, 5-, 10-, 25-, 50-, 100-, and 500-year recurrence intervals for rural streams that are regulated by Natural Resources Conservation Service floodwater retarding structures. Basin characteristics and streamflow statistics cannot be computed for locations in playa basins (mostly in the Oklahoma Panhandle) and along main stems of the largest river systems in the state, namely the Arkansas, Canadian, Cimarron, Neosho, Red, and Verdigris Rivers, because parts of the drainage areas extend outside of the processed hydrologic units.

SEASONAL VARIATIONS OF DISSOLVED MERCURY CONCENTRATIONS AT THE SULPHUR BANK MERCURY MINE, CLEAR LAKE, CALIFORNIA: IMPLICATIONS FOR MINE DRAINAGE MONITORING

EPA Science Inventory

The Sulphur Bank Mercury Mine in Lake County, California (SBMM) was operated from the 1860s through the 1950s. Mining for sulfur started with surface operations and then progressed to shaft and later open pit techniques to obtain mercury. SBMM is located adjacent to the shore o...

Accounting for sensor calibration, data validation, measurement and sampling uncertainties in monitoring urban drainage systems.

PubMed

Bertrand-Krajewski, J L; Bardin, J P; Mourad, M; Béranger, Y

2003-01-01

Assessing the functioning and the performance of urban drainage systems on both rainfall event and yearly time scales is usually based on online measurements of flow rates and on samples of influent effluent for some rainfall events per year. In order to draw pertinent scientific and operational conclusions from the measurement results, it is absolutely necessary to use appropriate methods and techniques in order to i) calibrate sensors and analytical methods, ii) validate raw data, iii) evaluate measurement uncertainties, iv) evaluate the number of rainfall events to sample per year in order to determine performance indicator with a given uncertainty. Based an previous work, the paper gives a synthetic review of required and techniques, and illustrates their application to storage and settling tanks. Experiments show that, controlled and careful experimental conditions, relative uncertainties are about 20% for flow rates in sewer pipes, 6-10% for volumes, 25-35% for TSS concentrations and loads, and 18-276% for TSS removal rates. In order to evaluate the annual pollutant interception efficiency of storage and settling tanks with a given uncertainty, efforts should first be devoted to decrease the sampling uncertainty by increasing the number of sampled events.

Transient ischaemic attacks due to a pulsating mass in the neck produced after incision and drainage of parapharyngeal abscess.

PubMed

Khan, Mohammad Iqbal; Tariq, Mohammad; Rashid, Danyal

2008-01-01

Carotid endarterectomy is the most commonly performed vascular surgical procedure. One of the complications of carotid endarterectomy is Pseudoaneurysm of the carotid artery frequently managed by endo-vascular technique. Pseudoaneurysm caused by other aetiological factors is rare entity. Penetrating trauma and neck surgery are known but very rare causes of pseudo aneurysm of the carotid artery. We have successfully managed a case of carotid artery pseudoaneurysm caused by incision and drainage of parapharyngeal abscess. This surgery also leads to the palsy of right vagus nerve causing complete hoarseness of voice. The patient presented with Transit Ischaemic Attacks (TIA) and amurosis fugos. Resection of aneurysm and reconstruction of right carotid artery lead to complete recovery. Vocal cord palsy was managed by Vox implant injection leading to full recovery.

A framework to support decision making in the selection of sustainable drainage system design alternatives.

PubMed

Wang, Mingming; Sweetapple, Chris; Fu, Guangtao; Farmani, Raziyeh; Butler, David

2017-10-01

This paper presents a new framework for decision making in sustainable drainage system (SuDS) scheme design. It integrates resilience, hydraulic performance, pollution control, rainwater usage, energy analysis, greenhouse gas (GHG) emissions and costs, and has 12 indicators. The multi-criteria analysis methods of entropy weight and Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) were selected to support SuDS scheme selection. The effectiveness of the framework is demonstrated with a SuDS case in China. Indicators used include flood volume, flood duration, a hydraulic performance indicator, cost and resilience. Resilience is an important design consideration, and it supports scheme selection in the case study. The proposed framework will help a decision maker to choose an appropriate design scheme for implementation without subjectivity. Copyright © 2017 Elsevier Ltd. All rights reserved.

Techniques for estimating flood hydrographs for ungaged urban watersheds

USGS Publications Warehouse

Stricker, V.A.; Sauer, V.B.

1984-01-01

The Clark Method, modified slightly was used to develop a synthetic, dimensionless hydrograph which can be used to estimate flood hydrographs for ungaged urban watersheds. Application of the technique results in a typical (average) flood hydrograph for a given peak discharge. Input necessary to apply the technique is an estimate of basin lagtime and the recurrence interval peak discharge. Equations for this purpose were obtained from a recent nationwide study on flood frequency in urban watersheds. A regression equation was developed which relates flood volumes to drainage area size, basin lagtime, and peak discharge. This equation is useful where storage of floodwater may be a part of design of flood prevention. (USGS)

The Positive Environmental Contribution of Jarosite by Retaining Lead in Acid Mine Drainage Areas

PubMed Central

Figueiredo, Maria-Ondina; da Silva, Teresa Pereira

2011-01-01

Jarosite, KFe3(SO4)2(OH)6, is a secondary iron sulphate often found in acid mine drainage (AMD) environments, particularly in mining wastes from polymetallic sulphide ore deposits. Despite the negative environmental connotation usually ascribed to secondary sulphate minerals due to the release of hazardous elements to aquifers and soils, jarosite acts as an efficient remover and immobilizer of such metals, particularly lead. The mineral chemistry of jarosite is reviewed and the results of a Fe K-edge XANES (X-Ray Absorption Near-Edge Structure) study of K-, Na- and Pb-jarosite are described and discussed within the context of the abandoned old mines of São Domingos and Aljustrel located in southern Portugal, in the Iberian Pyrite Belt (IPB). PMID:21655138

Development and Optimization of Gas-Assisted Gravity Drainage (GAGD) Process for Improved Light Oil Recovery

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dandina N. Rao; Subhash C. Ayirala; Madhav M. Kulkarni

This is the final report describing the evolution of the project ''Development and Optimization of Gas-Assisted Gravity Drainage (GAGD) Process for Improved Light Oil Recovery'' from its conceptual stage in 2002 to the field implementation of the developed technology in 2006. This comprehensive report includes all the experimental research, models developments, analyses of results, salient conclusions and the technology transfer efforts. As planned in the original proposal, the project has been conducted in three separate and concurrent tasks: Task 1 involved a physical model study of the new GAGD process, Task 2 was aimed at further developing the vanishing interfacialmore » tension (VIT) technique for gas-oil miscibility determination, and Task 3 was directed at determining multiphase gas-oil drainage and displacement characteristics in reservoir rocks at realistic pressures and temperatures. The project started with the task of recruiting well-qualified graduate research assistants. After collecting and reviewing the literature on different aspects of the project such gas injection EOR, gravity drainage, miscibility characterization, and gas-oil displacement characteristics in porous media, research plans were developed for the experimental work to be conducted under each of the three tasks. Based on the literature review and dimensional analysis, preliminary criteria were developed for the design of the partially-scaled physical model. Additionally, the need for a separate transparent model for visual observation and verification of the displacement and drainage behavior under gas-assisted gravity drainage was identified. Various materials and methods (ceramic porous material, Stucco, Portland cement, sintered glass beads) were attempted in order to fabricate a satisfactory visual model. In addition to proving the effectiveness of the GAGD process (through measured oil recoveries in the range of 65 to 87% IOIP), the visual models demonstrated three possible multiphase mechanisms at work, namely, Darcy-type displacement until gas breakthrough, gravity drainage after breakthrough and film-drainage in gas-invaded zones throughout the duration of the process. The partially-scaled physical model was used in a series of experiments to study the effects of wettability, gas-oil miscibility, secondary versus tertiary mode gas injection, and the presence of fractures on GAGD oil recovery. In addition to yielding recoveries of up to 80% IOIP, even in the immiscible gas injection mode, the partially-scaled physical model confirmed the positive influence of fractures and oil-wet characteristics in enhancing oil recoveries over those measured in the homogeneous (unfractured) water-wet models. An interesting observation was that a single logarithmic relationship between the oil recovery and the gravity number was obeyed by the physical model, the high-pressure corefloods and the field data.« less

A novel drainage technique during micropercutaneous nephrolithotomy in pediatric patients: double angiocath.

PubMed

Penbegul, Necmettin; Utangac, Mehmet Mazhar; Daggulli, Mansur; Dede, Onur; Bozkurt, Yasar; Bodakci, Mehmet Nuri; Atar, Murat

2016-06-01

Micropercutaneous nephrolithotomy (microperc) is a recently introduced percutaneous nephrolithotomy (PNL) technique that has the smallest tract size. The absence of an amplatz sheath during the microperc technique is a fundamental difference that distinguishes it from all other types of PNL (standard, mini, ultramini). Increasing of the intrarenal pelvic pressure (IPP) was demonstrated by the authors in adult patients but this problem may be even more serious in pediatric patients. Previously, the authors defined the use of a 14 gauge angiocath needle and sheath (microsheath) during microperc surgery for pediatric patient to reduce the IPP. In this novel technique, a second angiocath is used to access the renal collecting system to drain fluid during surgery. This technique is more effective in reducing IPP during microperc, especially in pediatric patients. Copyright © 2016 Elsevier Inc. All rights reserved.

Cerebrospinal fluid rhinorrhoea following transsphenoidal surgery for pituitary adenoma: experience in a Chinese centre.

PubMed

Zhang, C; Ding, X; Lu, Y; Hu, L; Hu, G

2017-08-01

The aim of this study was to elucidate the risk factors for cerebrospinal fluid (CSF) rhinorrhoea following transsphenoidal surgery and discuss its prevention and treatments. We retrospectively reviewed 474 consecutive cases of pituitary adenoma treated with 485 transsphenoidal surgical procedures from January 2008 to December 2011 in our department. We analysed the incidence of intra- and post-operative CSF leakage and outcomes of various repair strategies. Intra-operative CSF leakage was encountered in 85 cases (17.9%), and post-operative CSF rhinorrhoea in 13 cases (2.7%). Seven of the 13 patients with post-operative CSF rhinorrhoea did not experience intra-operative CSF leakage; three of these patients had adrenocorticotropic hormone-secreting adenomas. Of the remaining 6 patients with both intra- and post-operative CSF leakage, 2 were treated for giant invasive prolactinomas, and 2 had previously undergone transsphenoidal surgery. In eight patients, the leak was resolved by lumbar puncture, lumbar external drainage, resting in a semi-reclining position, or other conservative treatment. Two CSF leaks were repaired with gelatine foam and fibrin glue using a transsphenoidal approach, and two with autologous fat graft and sellar floor reconstruction using a transnasal endoscopic approach. After undergoing two transnasal endoscopic repairs, one patient with post-operative CSF rhinorrhoea was successfully treated by further lumbar subarachnoid drainage. In conclusion, procedures using gelatine foam, fibrin glue and autologous fat graft are common and effective techniques for the management of CSF rhinorrhoea after transsphenoidal surgery. When a CSF leak is detected during transsphenoidal surgery, thorough sellar reconstruction and long-term follow-up are necessary. © Copyright by Società Italiana di Otorinolaringologia e Chirurgia Cervico-Facciale, Rome, Italy.

An improved electronic twist-drill craniostomy procedure with post-operative urokinase instillation in treating chronic subdural hematoma.

PubMed

Lu, Jing; Shen, Dongwei; Hu, Fangjin; Zhou, Jianjun; Lan, Folin; Guo, Dongbing; Liu, Tianqing

2015-09-01

Twist-drill craniostomy (TDC) with closed-system drainage is a less invasive surgical technique for the treatment of chronic subdural hematoma (CSDH), but results in a higher disease recurrence rate. Therefore, we aimed to modify the TDC procedure in order to reduce the recurrence rate and further decrease complications. We retrospectively reviewed 230 cases of standard CSDH in 202 patients treated in our hospital between January 2006 and December 2013. We employed a new TDC device called micro-steel-needle-tube-bit for puncture and drainage. We chose an entry point 0.5cm anterior to the coronal suture at the superior temporal line and maintained post-operative drainage with urokinase instillation into the hematoma cavity. Clinical performance was assessed and compared by the Markwalder Grading Scale (MGS) score during the pre-operative period and at discharge. Recurrence of CSDH and complications were also recorded. Mean operation time was only 8.9 (6-13) min. Mean catheter indwelling duration and hospital stay were 1.18 (271/230, 1-3) and 2.27 (458/202, 2-9) days, respectively. The average frequency of urokinase instillation was 1.14 (262/230, 1-3) times. Intracerebral and sub-arachnoid hemorrhages were found in one patient, but were not in the puncture pathway. No perioperative deaths occurred. Recurrence was observed in only one patient at 28 days post-operation. Among 202 patients, 193 (95.54%) showed improved clinical symptoms and neurological function, and significantly lower MGS scores at discharge than pre-operation (0.13±0.45 vs. 1.37±0.55, P<0.01). In conclusion, electric TDC with micro-steel-needle-tube-bit at the pre-coronal suture entry point might be a safer, simpler, and faster mini-invasive surgical procedure for CSDH treatment. Post-operative drainage with instillation of urokinase could dramatically shorten drainage time and decrease recurrence rate. Copyright © 2015 Elsevier B.V. All rights reserved.

A Novel Uncultured Bacterium of the Family Gallionellaceae: Description and Genome Reconstruction Based on the Metagenomic Analysis of Microbial Community in Acid Mine Drainage.

PubMed

Kadnikov, V V; Ivasenko, D A; Beletsky, A V; Mardanov, A V; Danilova, E V; Pimenov, N V; Karnachuk, O V; Ravin, N V

2016-07-01

Drainage waters at the metal mining areas often have low pH and high content of dissolved metals due to oxidation of sulfide minerals. Extreme conditions limit microbial diversity in- such ecosystems. A drainage water microbial community (6.5'C, pH 2.65) in an open pit at the Sherlovaya Gora polymetallic open-cast mine (Transbaikal region, Eastern Siberia, Russia) was studied using metagenomic techniques. Metagenome sequencing provided information for taxonomic and functional characterization of the micro- bial community. The majority of microorganisms belonged to a single uncultured lineage representing a new Betaproteobacteria species of the genus Gallionella. While no.acidophiles are known among the cultured members of the family Gallionellaceae, similar 16S rRNA gene sequences were detected in acid mine drain- ages. Bacteria ofthe genera Thiobacillus, Acidobacterium, Acidisphaera, and Acidithiobacillus,-which are com- mon in acid mine drainage environments, were the minor components of the community. Metagenomic data were -used to determine the almost complete (-3.4 Mb) composite genome of the new bacterial. lineage desig- nated Candidatus Gallionella acididurans ShG14-8. Genome analysis revealed that Fe(II) oxidation probably involved the cytochromes localized on the outer membrane of the cell. The electron transport chain included NADH dehydrogenase, a cytochrome bc1 complex, an alternative complex III, and cytochrome oxidases of the bd, cbb3, and bo3 types. Oxidation of reduced sulfur compounds probably involved the Sox system, sul- fide-quinone oxidoreductase, adenyl sulfate reductase, and sulfate adenyltransferase. The genes required for autotrophic carbon assimilation via the Calvin cycle were present, while no pathway for nitrogen fixation was revealed. High numbers of RND metal transporters and P type ATPases were probably responsible for resis- tance to heavy metals. The new microorganism was an aerobic chemolithoautotroph of the group of psychrotolerant iron- and sulfur-oxidizing acidophiles of the family Gallionellaceae, which are common in acid mine drainages.

SSh versus TSE sequence protocol in rapid MR examination of pediatric patients with programmable drainage system.

PubMed

Brichtová, Eva; Šenkyřík, J

2017-05-01

A low radiation burden is essential during diagnostic procedures in pediatric patients due to their high tissue sensitivity. Using MR examination instead of the routinely used CT reduces the radiation exposure and the risk of adverse stochastic effects. Our retrospective study evaluated the possibility of using ultrafast single-shot (SSh) sequences and turbo spin echo (TSE) sequences in rapid MR brain imaging in pediatric patients with hydrocephalus and a programmable ventriculoperitoneal drainage system. SSh sequences seem to be suitable for examining pediatric patients due to the speed of using this technique, but significant susceptibility artifacts due to the programmable drainage valve degrade the image quality. Therefore, a rapid MR examination protocol based on TSE sequences, less sensitive to artifacts due to ferromagnetic components, has been developed. Of 61 pediatric patients who were examined using MR and the SSh sequence protocol, a group of 15 patients with hydrocephalus and a programmable drainage system also underwent TSE sequence MR imaging. The susceptibility artifact volume in both rapid MR protocols was evaluated using a semiautomatic volumetry system. A statistically significant decrease in the susceptibility artifact volume has been demonstrated in TSE sequence imaging in comparison with SSh sequences. Using TSE sequences reduced the influence of artifacts from the programmable valve, and the image quality in all cases was rated as excellent. In all patients, rapid MR examinations were performed without any need for intravenous sedation or general anesthesia. Our study results strongly suggest the superiority of the TSE sequence MR protocol compared to the SSh sequence protocol in pediatric patients with a programmable ventriculoperitoneal drainage system due to a significant reduction of susceptibility artifact volume. Both rapid sequence MR protocols provide quick and satisfactory brain imaging with no ionizing radiation and a reduced need for intravenous or general anesthesia.

Drainage Evolution during the Uplift of the Central Anatolia Plateau

NASA Astrophysics Data System (ADS)

Brocard, G. Y.; Meijers, M. J.; Willenbring, J. K.; Kaymakci, N.; Whitney, D. L.

2015-12-01

The Central Anatolian plateau formed in the past 8-6 Myrs, associated to a change in tectonic regime, from contraction to extensional escape tectonics. We have examined the response of the river drainage of Central Anatolia to the rise of the plateau uplift and to the formation of the Anatolian microplate, tracking changes in drainage organization. Anatolia experienced widespread rock uplift and erosion in the Late Oligocene, generating a narrow, steep, and quickly eroding mountain range above the future southern plateau margin. A regionally widespread marine transgression resulted from wholesale foundering of this orogen in Early Miocene time. Widespread planation surfaces overlapped by Miocene marine carbonates bevel this topography, indicating that relief had been reduced to a low elevation pedimented landscape by the end of the Middle Miocene. Plateau uplift initiated around 11 My ago in Eastern Anatolia; it was echoed in Central Anatolia by a short-lived phase of contraction and localized uplifts that predate escape tectonics and mark the beginning of the current topographic differentiation of the southern plateau margin. The through-going drainage network inherited disintegrated, and a vast zone of inward drainage formed at the location of the future plateau interior. Between 8 and 6 My, the southern plateau margin (i.e. the Tauride Mountains) emerged. δ18O analyses on lacustrine and pedogenic carbonates show that the southern plateau margin, if not the plateau interior, had experienced enough uplift by 5 My to generate a substantial rain shadow over the plateau interior. Being disconnected from the regional base level from the start, the plateau interior was able to rise without experiencing substantial dissection. It reconnected to all surrounding sediment sinks (Mediterranean Sea, Black Sea and Persian Gulf) over the past 5 My. We discuss the mechanisms that have driven this reconnection. Bottom-up processes of integration such as drainage divide retreat did not produce any major changes. Top-down processes such as lake overflow and avulsion achieved most of the re-integration. They result from more positive precipitation/evaporation balances, either due to elevation change during plateau uplift or due to tectonic fragmentation of depocenters during the development of escape tectonics.

Comparison of different uncertainty techniques in urban stormwater quantity and quality modelling.

PubMed

Dotto, Cintia B S; Mannina, Giorgio; Kleidorfer, Manfred; Vezzaro, Luca; Henrichs, Malte; McCarthy, David T; Freni, Gabriele; Rauch, Wolfgang; Deletic, Ana

2012-05-15

Urban drainage models are important tools used by both practitioners and scientists in the field of stormwater management. These models are often conceptual and usually require calibration using local datasets. The quantification of the uncertainty associated with the models is a must, although it is rarely practiced. The International Working Group on Data and Models, which works under the IWA/IAHR Joint Committee on Urban Drainage, has been working on the development of a framework for defining and assessing uncertainties in the field of urban drainage modelling. A part of that work is the assessment and comparison of different techniques generally used in the uncertainty assessment of the parameters of water models. This paper compares a number of these techniques: the Generalized Likelihood Uncertainty Estimation (GLUE), the Shuffled Complex Evolution Metropolis algorithm (SCEM-UA), an approach based on a multi-objective auto-calibration (a multialgorithm, genetically adaptive multi-objective method, AMALGAM) and a Bayesian approach based on a simplified Markov Chain Monte Carlo method (implemented in the software MICA). To allow a meaningful comparison among the different uncertainty techniques, common criteria have been set for the likelihood formulation, defining the number of simulations, and the measure of uncertainty bounds. Moreover, all the uncertainty techniques were implemented for the same case study, in which the same stormwater quantity and quality model was used alongside the same dataset. The comparison results for a well-posed rainfall/runoff model showed that the four methods provide similar probability distributions of model parameters, and model prediction intervals. For ill-posed water quality model the differences between the results were much wider; and the paper provides the specific advantages and disadvantages of each method. In relation to computational efficiency (i.e. number of iterations required to generate the probability distribution of parameters), it was found that SCEM-UA and AMALGAM produce results quicker than GLUE in terms of required number of simulations. However, GLUE requires the lowest modelling skills and is easy to implement. All non-Bayesian methods have problems with the way they accept behavioural parameter sets, e.g. GLUE, SCEM-UA and AMALGAM have subjective acceptance thresholds, while MICA has usually problem with its hypothesis on normality of residuals. It is concluded that modellers should select the method which is most suitable for the system they are modelling (e.g. complexity of the model's structure including the number of parameters), their skill/knowledge level, the available information, and the purpose of their study. Copyright © 2012 Elsevier Ltd. All rights reserved.

Endoscopic and percutaneous drainage of symptomatic walled-off pancreatic necrosis reduces hospital stay and radiographic resources.

PubMed

Gluck, Michael; Ross, Andrew; Irani, Shayan; Lin, Otto; Hauptmann, Ellen; Siegal, Justin; Fotoohi, Mehran; Crane, Robert; Robinson, David; Kozarek, Richard A

2010-12-01

Walled-off pancreatic necrosis (WOPN), a complication of severe acute pancreatitis (SAP), can become infected, obstruct adjacent structures, and result in clinical deterioration of patients. Patients with WOPN have prolonged hospitalizations, needing multiple radiologic and medical interventions. We compared an established treatment of WOPN, standard percutaneous drainage (SPD), with combined modality therapy (CMT), in which endoscopic transenteric stents were added to a regimen of percutaneous drains. Symptomatic patients with WOPN between January 2006 and August 2009 were treated with SPD (n = 43, 28 male) or CMT (n = 23, 17 male) and compared by disease severity, length of hospitalization, duration of drainage, complications, and number of radiologic and endoscopic procedures. Patient age (59 vs 54 years), sex (77% vs 58% male), computed tomography severity index (8.0 vs 7.2), number of endoscopic retrograde cholangiopancreatographies (2.0 vs 2.6), and percentage with disconnected pancreatic ducts (50% vs 46%) were equivalent in the CMT and SPD arms, respectively. Patients undergoing CMT had significantly decreased length of hospitalization (26 vs 55 days, P < .0026), duration of external drainage (83.9 vs 189 days, P < .002), number of computed tomography scans (8.95 vs 14.3, P < .002), and drain studies (6.5 vs 13, P < .0001). Patients in the SPD arm had more complications. For patients with symptomatic WOPN, CMT provided a more effective and safer management technique, resulting in shorter hospitalizations and fewer radiologic procedures than SPD. Copyright © 2010 AGA Institute. Published by Elsevier Inc. All rights reserved.

Effect Of Preoperative Intravenous Steroids On Seroma Formation After Modified Radical Mastectomy.

PubMed

Khan, Maryam Alam

2017-01-01

With the steep increase in breast cancer incidence globally and regionally, there has been a trend toward reducing patient morbidity by meticulous surgical techniques to obviate complications like seroma formation; use to pre-operative steroids seems to be convenient, cost effective and shows promising results in trials. This randomized clinical trial was conducted at Surgical Department of Khyber Teaching Hospital Peshawar, from January 2012 to April 2014 on 65 patients randomly allocated to Group A and Group B using lottery method. Group A underwent MRM+AD in the conventional manner while Group B received a 120 mg of injection Depomedrol intravenously 1 hour before the surgery. The two were compared in terms of total drainage, days of drainage, wound complications and incidence of seroma. Data was entered and analysed using statistical program SPSS-21. The mean age in group A was 34.2±10.1 years and B was 32.3±9.1 years. The mean drainage in intervention group was significantly reduced as compared to control group (755.4±65ml vs 928.3±102.5). Total drainage days were reduced (6.5±1.6 days vs 10.2±2.2 days) and incidence of seroma was also reduced (A=18.75% vs B=6.06%). However, three patients in group B had wound infection. Seroma formation is the most common complication of Mastectomy and among the methods used to reduce its incidence, steroid administration seems to be the most cost effective and shows promising results.

A first-in-man study of 68Ga-nanocolloid PET-CT sentinel lymph node imaging in prostate cancer demonstrates aberrant lymphatic drainage pathways.

PubMed

Doughton, Jacki A; Hofman, Michael S; Eu, Peter; Hicks, Rodney J; Williams, Scott G

2018-05-04

Purpose: To assess feasibility, safety and utility of a novel 68 Ga-nanocolloid radio-tracer with PET-CT lymphoscintigraphy for identification of sentinel lymph nodes (SLN). Methods: Pilot study of patients from a tertiary cancer hospital who required insertion of gold fiducials for prostate cancer radiation therapy. Participation did not affect cancer management. Ultrasound-guided transperineal intra-prostatic injection of PET tracer (iron oxide nanocolloid labelled with gallium-68) after placement of fiducials. PET-CT lymphoscintigraphy imaging at approximately 45 and 100 minutes after in-jection of tracer. The study was monitored using Bayesian trial design with the as-sumption that at least one sentinel lymph node (SLN) could be identified in at least two-thirds of cases with >80% confidence. Results: SLN identification was successful in all 5 participants, allowing completion of the pilot study as per protocol. No adverse effects were observed. Unexpected po-tential pathways for transit of malignant cells as well as expected regional drainage pathways were discovered. Rapid tracer drainage to pelvic bone, perivesical, mesorec-tal, inguinal and Virchow's nodes was identified. Conclusion: SLN identification using 68 Ga-nanocolloid PET-CT can be successfully performed. Non-traditional pathways of disease spread were identified including drainage to pelvic bone as well as perivesical, mesorectal, inguinal and Virchow's nodes. Prevalence of both aberrant and non-lymphatic pathways of spread should be further investigated with this technique. Copyright © 2018 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

Management of pancreatic fluid collections: A comprehensive review of the literature

PubMed Central

Tyberg, Amy; Karia, Kunal; Gabr, Moamen; Desai, Amit; Doshi, Rushabh; Gaidhane, Monica; Sharaiha, Reem Z; Kahaleh, Michel

2016-01-01

Pancreatic fluid collections (PFCs) are a frequent complication of pancreatitis. It is important to classify PFCs to guide management. The revised Atlanta criteria classifies PFCs as acute or chronic, with chronic fluid collections subdivided into pseudocysts and walled-off pancreatic necrosis (WOPN). Establishing adequate nutritional support is an essential step in the management of PFCs. Early attempts at oral feeding can be trialed in patients with mild pancreatitis. Enteral feeding should be implemented in patients with moderate to severe pancreatitis. Jejunal feeding remains the preferred route of enteral nutrition. Symptomatic PFCs require drainage; options include surgical, percutaneous, or endoscopic approaches. With the advent of newer and more advanced endoscopic tools and expertise, and an associated reduction in health care costs, minimally invasive endoscopic drainage has become the preferable approach. An endoscopic ultrasonography-guided approach using a seldinger technique is the preferred endoscopic approach. Both plastic stents and metal stents are efficacious and safe; however, metal stents may offer an advantage, especially in infected pseudocysts and in WOPN. Direct endoscopic necrosectomy is often required in WOPN. Lumen apposing metal stents that allow for direct endoscopic necrosectomy and debridement through the stent lumen are preferred in these patients. Endoscopic retrograde cholangio pancreatography with pancreatic duct (PD) exploration should be performed concurrent to PFC drainage. PD disruption is associated with an increased severity of pancreatitis, an increased risk of recurrent attacks of pancreatitis and long-term complications, and a decreased rate of PFC resolution after drainage. Any pancreatic ductal disruption should be bridged with endoscopic stenting. PMID:26900288

Assessment of morphometric characteristics of Chakrar watershed in Madhya Pradesh India using geospatial technique

NASA Astrophysics Data System (ADS)

Soni, Sandeep

2017-09-01

The quantitative analysis of the watershed is important for the quantification of the channel network and to understand its geo-hydrological behaviour. Assessment of drainage network and their relative parameters have been quantitatively carried out for the Chakrar watershed of Madhya Pradesh, India, to understand the prevailing geological variation, topographic information and structural setup of the watershed and their interrelationship. Remote Sensing and Geographical Information System (GIS) has been used for the delineation and calculation of the morphometric parameters of the watershed. The Chakrar watershed is sprawled over an area of 415 km2 with dendritic, parallel and trellis drainage pattern. It is sub-divided into nine sub-watersheds. The study area is designated as sixth-order basin and lower and middle order streams mostly dominate the basin with the drainage density value of 2.46 km/km2 which exhibits gentle to steep slope terrain, medium dense vegetation, and less permeable with medium precipitation. The mean bifurcation value of the basin is 4.16 and value of nine sub-watersheds varies from 2.83 to 4.44 which reveals drainage networks formed on homogeneous rocks when the influences of geologic structures on the stream network is negligible. Form factor, circularity ratio and elongation ratio indicate an elongated basin shape having less prone to flood, lower erosion and sediment transport capacities. The results from the morphometric assessment of the watershed are important in water resources evaluation and its management and for the selection of recharge structure in the area for future water management.

Geomorphometry of Drainage Basin for Natural Resources Management Using High Resolution Satellite Data an Indian Example

NASA Astrophysics Data System (ADS)

Venkateswarlu, P.; Reddy, M. A.; Prasad, A. T.

2003-12-01

Application of Remote Sensing and Geographic Information System for the development of land and water resources action plan at micro level for appropriate management of land/water resources of a watershed in rain fed region of Prakasam District in Andhra Pradesh, India forms the focal theme of this paper. The quantitative description of drainage basin geometry can be effectively determined using Remote Sensing and GIS techniques. Each of the sixty-two sub-watersheds of the study area have been studied in terms of the Morphometric parameters - Stream length, Bifurcation ratio, Length ratio, Drainage density, Stream frequency, Texture ratio, Form factor, Area Perimeters, Circularity ratio and Elongation ratio and prioritized all the sub-watersheds under study. The prioritization of sub sheds based on morphometry is compared with sediment yield prioritization and found nearly same for the study area. The information obtained from the thematic maps are integrated and action plans are suggested for land and water resources development on a sustainable basis. Landuse/Landcover, Hydrogeomorphology and Soil thematic maps were generated. In addition slope and Drainage maps were prepared from Survey of India toposheets. Based on the computerized database created using ARC/INFO software, information derived in terms of natural resources and their spatial distribution was then integrated with the socio economic data to formulate an action plan, which includes suggestion of alternative Landuse/Landcover practices. Such a plan is useful for natural resources management and for improving the socio-economic status of rural population on a sustainable basis. Keywords: Natural Resources, Remote Sensing, Morphometry sustainable development.

Multiple pancreaticoduodenal penetrating gunshot trauma evolving into acute necrotizing pancreatitis. A combined surgical and minimally invasive approach.

PubMed

Testini, Mario; Piccinni, Giuseppe; Pedote, Pasquale; Lissidini, Germana; Gurrado, Angela; Lardo, Domenica; Greco, Luigi; Marzaioli, Rinaldo

2008-09-02

Shotgun injuries are the cause of increasing surgical problems related to the proliferation of firearms. Gunshot pancreaticoduodenal traumas are unusual in urban trauma units. Their management remains complex because of the absence of standardized, universal guidelines for treatment and the high incidence of associated lesions of major vessels as well as of other gastrointestinal structures. Surgical treatment is still controversial, and the possibilities offered by the safe and effective mini-invasive techniques seem to open new, articulated perspectives for the treatment of pancreaticoduodenal injury complications. We present the case of a 27-year-old man with multiple penetrating gunshot trauma evolving into acute necrotizing pancreatitis, treated by combining a surgical with a mini-invasive approach. At admission, he presented a Glasgow Coma Score of 4 due to severe hemorrhagic shock. First, surgical hemostasis, duodenogastric resection, multiple intestinal resections, peripancreatic and thoracic drainage were carried out as emergency procedures. On the 12th postoperative day, the patient underwent re-surgery with toilette, external duodenal drainage with Foley tube and peripancreatic drainage repositioning as a result of a duodenal perforation due to acute necrotizing pancreatitis. Eight days later, following the accidental removal of the peripancreatic drains, a CT scan was done showing a considerable collection of fluid in the epiploon retrocavity. Percutaneous CT-guided drainage was performed by inserting an 8.5 Fr pigtail catheter, thus avoiding further re-operation. The patient was successfully discharged on the 80th postoperative day. The treatment of multiple pancreaticoduodenal penetrating gunshot traumas should focus on multidisciplinary surgical and minimally invasive treatment to optimize organ recovery.

Inhibition of bacterial activity in acid mine drainage

NASA Astrophysics Data System (ADS)

Singh, Gurdeep; Bhatnagar, Miss Mridula

1988-12-01

Acid mine drainage water give rise to rapid growth and activity of an iron- and sulphur- oxidizing bacterium Thiobacillus ferrooxidians which greatly accelerate acid producing reactions by oxidation of pyrite material associated with coal and adjoining strata. The role of this bacterium in production of acid mine drainage is described. This study presents the data which demonstrate the inhibitory effect of certain organic acids, sodium benzoate, sodium lauryl sulphate, quarternary ammonium compounds on the growth of the acidophilic aerobic autotroph Thiobacillus ferrooxidians. In each experiment, 10 milli-litres of laboratory developed culture of Thiobacillus ferrooxidians was added to 250 milli-litres Erlenmeyer flask containing 90 milli-litres of 9-k media supplemented with FeSO4 7H2O and organic compounds at various concentrations. Control experiments were also carried out. The treated and untreated (control) samples analysed at various time intervals for Ferrous Iron and pH levels. Results from this investigation showed that some organic acids, sodium benzoate, sodium lauryl sulphate and quarternary ammonium compounds at low concentration (10-2 M, 10-50 ppm concentration levels) are effective bactericides and able to inhibit and reduce the Ferrous Iron oxidation and acidity formation by inhibiting the growth of Thiobacillus ferrooxidians is also discussed and presented

Constructed wetlands in UK urban surface drainage systems.

PubMed

Shutes, B; Ellis, J B; Revitt, D M; Scholes, L N L

2005-01-01

This paper presents the outcome of an inventory of planted wetland systems in the UK which are classified according to land use type and are all examples of sustainable drainage systems. The introduction of constructed wetlands to treat surface runoff essentially followed a 1997 Environment Agency for England and Wales report advocating the use of "soft engineered" facilities including wetlands in the context of sustainable development and Agenda 21. Subsequently published reports by the UK Construction Industry Research and Information Association (CIRIA) have promoted the potential benefits to both developer and the community of adopting constructed wetlands and other vegetated systems as a sustainable drainage approach. In addition, the UK Environment Agency and Highways Agency (HA) have recently published their own design criteria and requirements for vegetative control and treatment of road runoff. A case study of the design and performance of a constructed wetland system for the treatment of road runoff is discussed. The performance of these systems will be assessed in terms of their design criteria, runoff loadings as well as vegetation and structure maintenance procedures. The differing design approaches in guidance documents published in the UK by the Environment Agency, CIRIA and HA will also be evaluated.

Refractory diabetes insipidus following drainage of chronic subdural haematoma.

PubMed

Won, Yu Deok; Kim, Choong Hyun; Cheong, Jin Hwan; Kim, Jae Min

2013-01-01

Post-traumatic diabetes insipidus (DI) is a relatively common complication after head injury. The authors report a fatal case of refractory DI, which developed in a patient with chronic subdural haematoma. A 38-year-old woman presented to the emergency room with a headache for over a week. She was alert and neurological examination demonstrated no significant deficits or external wounds in her head. Brain computed tomography (CT) scans revealed a small amount of chronic subdural haematoma bilaterally. She was treated conservatively and her hospital course was uneventful until she developed a convulsive seizure and mental change on the 3rd day after admission. Immediate follow-up CT scans showed no significant change in the amount of haemorrhage except effacement of gyral marking. Bilateral trephination and drainage of the haematoma were performed immediately. Post-operatively, she developed a refractory DI and was managed in the intensive care unit. However, she died on the 6th day after the operation ultimately. The authors emphasize the importance of timely drainage of chronic subdural haematoma to prevent a fatal endocrinologic complication after head injury. This study also discusses the possible mechanism of DI after head injury, management and review of the pertinent literatures.

Focal hepatic fatty infiltration in the posterior edge of the medial segment associated with aberrant gastric venous drainage: CT, US, and MR findings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kawamori, Yashuiro; Matsui, Osamu; Takahashi, S.

1996-05-01

The purpose of this study is to demonstrate the relation between focal hepatic fatty infiltration and aberrant gastric venous drainage (AGVD) in the posterior edge of the medial segment (PEMS) of the liver and we present two cases of focal hepatic fatty infiltration with AGVD in the PEMS and discuss their imaging features. In both cases the focal fatty infiltration areas were hyperechoic on sonography, hypodense on CT, and hyperintense on T1-weighted MRI. Computed tomography during arterial portography (CTAP) showed nodular perfusion defects corresponding to the areas in both cases, and early enhancement of the area was observed with dynamicmore » MRI in one case. Although the findings on CTAP and dynamic MRI suggested a neoplastic nature for the lesions, focal fatty infiltration was confirmed with surgical resection in one case and with imaging follow-up in the other. Aberrant gastric venous drainage into the area was demonstrated on arteriography in both cases. The variation in blood supply caused by AGVD may play an important role in fatty metabolism in the PENIS of the liver and may influence imaging features. 9 refs., 2 figs.« less

[Microbial diversity and ammonia-oxidizing microorganism of a soil sample near an acid mine drainage lake].

PubMed

Liu, Ying; Wang, Li-Hua; Hao, Chun-Bo; Li, Lu; Li, Si-Yuan; Feng, Chuan-Ping

2014-06-01

The main physicochemical parameters of the soil sample which was collected near an acid mine drainage reservoir in Anhui province was analyzed. The microbial diversity and community structure was studied through the construction of bacteria and archaea 16S rRNA gene clone libraries and ammonia monooxygenase gene clone library of archaea. The functional groups which were responsible for the process of ammonia oxidation were also discussed. The results indicated that the soil sample had extreme low pH value (pH < 3) and high ions concentration, which was influenced by the acid mine drainage (AMD). All the 16S rRNA gene sequences of bacteria clone library fell into 11 phyla, and Acidobacteria played the most significant role in the ecosystem followed by Verrucomicrobia. A great number of acidophilic bacteria existed in the soil sample, such as Candidatus Koribacter versatilis and Holophaga sp.. The archaea clone library consisted of 2 phyla (Thaumarchaeota and Euryarchaeota). The abundance of Thaumarchaeota was remarkably higher than Euryarchaeota. The ammonia oxidation in the soil environment was probably driven by ammonia-oxidizing archaea, and new species of ammonia-oxidizing archaea existed in the soil sample.

Methods for estimating flow-duration and annual mean-flow statistics for ungaged streams in Oklahoma

USGS Publications Warehouse

Esralew, Rachel A.; Smith, S. Jerrod

2010-01-01

Flow statistics can be used to provide decision makers with surface-water information needed for activities such as water-supply permitting, flow regulation, and other water rights issues. Flow statistics could be needed at any location along a stream. Most often, streamflow statistics are needed at ungaged sites, where no flow data are available to compute the statistics. Methods are presented in this report for estimating flow-duration and annual mean-flow statistics for ungaged streams in Oklahoma. Flow statistics included the (1) annual (period of record), (2) seasonal (summer-autumn and winter-spring), and (3) 12 monthly duration statistics, including the 20th, 50th, 80th, 90th, and 95th percentile flow exceedances, and the annual mean-flow (mean of daily flows for the period of record). Flow statistics were calculated from daily streamflow information collected from 235 streamflow-gaging stations throughout Oklahoma and areas in adjacent states. A drainage-area ratio method is the preferred method for estimating flow statistics at an ungaged location that is on a stream near a gage. The method generally is reliable only if the drainage-area ratio of the two sites is between 0.5 and 1.5. Regression equations that relate flow statistics to drainage-basin characteristics were developed for the purpose of estimating selected flow-duration and annual mean-flow statistics for ungaged streams that are not near gaging stations on the same stream. Regression equations were developed from flow statistics and drainage-basin characteristics for 113 unregulated gaging stations. Separate regression equations were developed by using U.S. Geological Survey streamflow-gaging stations in regions with similar drainage-basin characteristics. These equations can increase the accuracy of regression equations used for estimating flow-duration and annual mean-flow statistics at ungaged stream locations in Oklahoma. Streamflow-gaging stations were grouped by selected drainage-basin characteristics by using a k-means cluster analysis. Three regions were identified for Oklahoma on the basis of the clustering of gaging stations and a manual delineation of distinguishable hydrologic and geologic boundaries: Region 1 (western Oklahoma excluding the Oklahoma and Texas Panhandles), Region 2 (north- and south-central Oklahoma), and Region 3 (eastern and central Oklahoma). A total of 228 regression equations (225 flow-duration regressions and three annual mean-flow regressions) were developed using ordinary least-squares and left-censored (Tobit) multiple-regression techniques. These equations can be used to estimate 75 flow-duration statistics and annual mean-flow for ungaged streams in the three regions. Drainage-basin characteristics that were statistically significant independent variables in the regression analyses were (1) contributing drainage area; (2) station elevation; (3) mean drainage-basin elevation; (4) channel slope; (5) percentage of forested canopy; (6) mean drainage-basin hillslope; (7) soil permeability; and (8) mean annual, seasonal, and monthly precipitation. The accuracy of flow-duration regression equations generally decreased from high-flow exceedance (low-exceedance probability) to low-flow exceedance (high-exceedance probability) . This decrease may have happened because a greater uncertainty exists for low-flow estimates and low-flow is largely affected by localized geology that was not quantified by the drainage-basin characteristics selected. The standard errors of estimate of regression equations for Region 1 (western Oklahoma) were substantially larger than those standard errors for other regions, especially for low-flow exceedances. These errors may be a result of greater variability in low flow because of increased irrigation activities in this region. Regression equations may not be reliable for sites where the drainage-basin characteristics are outside the range of values of independent vari

Preoperative endoscopic versus percutaneous transhepatic biliary drainage in potentially resectable perihilar cholangiocarcinoma (DRAINAGE trial): design and rationale of a randomized controlled trial.

PubMed

Wiggers, Jimme K; Coelen, Robert J S; Rauws, Erik A J; van Delden, Otto M; van Eijck, Casper H J; de Jonge, Jeroen; Porte, Robert J; Buis, Carlijn I; Dejong, Cornelis H C; Molenaar, I Quintus; Besselink, Marc G H; Busch, Olivier R C; Dijkgraaf, Marcel G W; van Gulik, Thomas M

2015-02-14

Liver surgery in perihilar cholangiocarcinoma (PHC) is associated with high postoperative morbidity because the tumor typically causes biliary obstruction. Preoperative biliary drainage is used to create a safer environment prior to liver surgery, but biliary drainage may be harmful when severe drainage-related complications deteriorate the patients' condition or increase the risk of postoperative morbidity. Biliary drainage can cause cholangitis/cholecystitis, pancreatitis, hemorrhage, portal vein thrombosis, bowel wall perforation, or dehydration. Two methods of preoperative biliary drainage are mostly applied: endoscopic biliary drainage, which is currently used in most regional centers before referring patients for surgical treatment, and percutaneous transhepatic biliary drainage. Both methods are associated with severe drainage-related complications, but two small retrospective series found a lower incidence in the number of preoperative complications after percutaneous drainage compared to endoscopic drainage (18-25% versus 38-60%, respectively). The present study randomizes patients with potentially resectable PHC and biliary obstruction between preoperative endoscopic or percutaneous transhepatic biliary drainage. The study is a multi-center trial with an "all-comers" design, randomizing patients between endoscopic or percutaneous transhepatic biliary drainage. All patients selected to potentially undergo a major liver resection for presumed PHC are eligible for inclusion in the study provided that the biliary system in the future liver remnant is obstructed (even if they underwent previous inadequate endoscopic drainage). Primary outcome measure is the total number of severe preoperative complications between randomization and exploratory laparotomy. The study is designed to detect superiority of percutaneous drainage: a provisional sample size of 106 patients is required to detect a relative decrease of 50% in the number of severe preoperative complications (alpha = 0.95; beta = 0.8). Interim analysis after inclusion of 53 patients (50%) will provide the definitive sample size. Secondary outcome measures encompass the success of biliary drainage, quality of life, and postoperative morbidity and mortality. The DRAINAGE trial is designed to identify a difference in the number of severe drainage-related complications after endoscopic and percutaneous transhepatic biliary drainage in patients selected to undergo a major liver resection for perihilar cholangiocarcinoma. Netherlands Trial Register [ NTR4243 , 11 October 2013].

Prairie Pothole Region wetlands and subsurface drainage systems: Key factors for determining drainage setback distances

USGS Publications Warehouse

Tangen, Brian; Wiltermuth, Mark T.

2018-01-01

Use of agricultural subsurface drainage systems in the Prairie Pothole Region of North America continues to increase, prompting concerns over potential negative effects to the Region's vital wetlands. The U.S. Fish and Wildlife Service protects a large number of wetlands through conservation easements that often utilize standard lateral setback distances to provide buffers between wetlands and drainage systems. Because of a lack of information pertaining to the efficacy of these setback distances for protecting wetlands, information is required to support the decision making for placement of subsurface drainage systems adjacent to wetlands. We used qualitative graphical analyses and data comparisons to identify characteristics of subsurface drainage systems and wetland catchments that could be considered when assessing setback distances. We also compared setback distances with catchment slope lengths to determine if they typically exclude drainage systems from the catchment. We demonstrated that depth of a subsurface drainage system is a key factor for determining drainage setback distances. Drainage systems located closer to the surface (shallow) typically could be associated with shorter lateral setback distances compared with deeper systems. Subsurface drainage systems would be allowed within a wetland's catchment for 44–59% of catchments associated with wetland conservation easements in North Dakota. More specifically, results suggest that drainage setback distances generally would exclude drainage systems from catchments of the smaller wetlands that typically have shorter slopes in the adjacent upland contributing area. For larger wetlands, however, considerable areas of the catchment would be vulnerable to drainage that may affect wetland hydrology. U.S. Fish and Wildlife Service easements are associated with > 2,000 km2 of wetlands in North Dakota, demonstrating great potential to protect these systems from drainage depending on policies for installing subsurface drainage systems on these lands. The length of slope of individual catchments and depth of subsurface drainage systems could be considered when prescribing drainage setback distances and assessing potential effects to wetland hydrology. Moreover, because of uncertainties associated with the efficacy of standard drainage setback distances, exclusion of subsurface drainage systems from wetland catchments would be ideal when the goal is to protect wetlands.

Spontaneous esophageal-pleural fistula.

PubMed

Vyas, Sameer; Prakash, Mahesh; Kaman, Lileshwar; Bhardwaj, Nidhi; Khandelwal, Niranjan

2011-10-01

Spontaneous esophageal-pleural fistula (EPF) is a rare entity. We describe a case in a middle-aged female who presented with severe retrosternal chest pain and shortness of breadth. Chest computed tomography showed right EPF and hydropneumothorax. She was managed conservatively keeping the chest tube drainage and performing feeding jejunostomy. A brief review of the imaging finding and management of EPF is discussed.

Attributes for NHDPlus Catchments (Version 1.1) in the Conterminous United States: Artificial Drainage (1992) and Irrigation Types (1997)

USGS Publications Warehouse

Wieczorek, Michael; LaMotte, Andrew E.

2010-01-01

This tabular dataset represents the estimated area of artificial drainage for the year 1992 and irrigation types for the year 1997 compiled for every catchment of NHDPlus for the conterminous United States. The source datasets were derived from tabular National Resource Inventory (NRI) datasets created by the National Resources Conservation Service (NRCS, U.S. Department of Agriculture, 1995, 1997). Artificial drainage is defined as subsurface drains and ditches. Irrigation types are defined as gravity and pressure. Subsurface drains are described as conduits, such as corrugated plastic tubing, tile, or pipe, installed beneath the ground surface to collect and/or convey drainage. Surface drainage field ditches are described as graded ditches for collecting excess water. Gravity irrigation source is described as irrigation delivered to the farm and/or field by canals or pipelines open to the atmosphere; and water is distributed by the force of gravity down the field by: (1) A surface irrigation system (border, basin, furrow, corrugation, wild flooding, etc.) or (2) Sub-surface irrigation pipelines or ditches. Pressure irrigation source is described as irrigation delivered to the farm and/or field in pump or elevation-induced pressure pipelines, and water is distributed across the field by: (1) Sprinkle irrigation (center pivot, linear move, traveling gun, side roll, hand move, big gun, or fixed set sprinklers), or (2) Micro irrigation (drip emitters, continuous tube bubblers, micro spray or micro sprinklers). NRI data do not include Federal lands and are thus excluded from this dataset. The tabular data for drainage were spatially apportioned to the National Land Cover Dataset (NLCD, Kerie Hitt, written commun., 2005) and the tabular data for irrigation were spatially apportioned to an enhanced version of the National Land Cover Dataset (NLCDe, Nakagaki and others 2007) The NHDPlus Version 1.1 is an integrated suite of application-ready geospatial datasets that incorporates many of the best features of the National Hydrography Dataset (NHD) and the National Elevation Dataset (NED). The NHDPlus includes a stream network (based on the 1:100,00-scale NHD), improved networking, naming, and value-added attributes (VAAs). NHDPlus also includes elevation-derived catchments (drainage areas) produced using a drainage enforcement technique first widely used in New England, and thus referred to as "the New England Method." This technique involves "burning in" the 1:100,000-scale NHD and when available building "walls" using the National Watershed Boundary Dataset (WBD). The resulting modified digital elevation model (HydroDEM) is used to produce hydrologic derivatives that agree with the NHD and WBD. Over the past two years, an interdisciplinary team from the U.S. Geological Survey (USGS), and the U.S. Environmental Protection Agency (USEPA), and contractors, found that this method produces the best quality NHD catchments using an automated process (USEPA, 2007). The NHDPlus dataset is organized by 18 Production Units that cover the conterminous United States. The NHDPlus version 1.1 data are grouped by the U.S. Geological Survey's Major River Basins (MRBs, Crawford and others, 2006). MRB1, covering the New England and Mid-Atlantic River basins, contains NHDPlus Production Units 1 and 2. MRB2, covering the South Atlantic-Gulf and Tennessee River basins, contains NHDPlus Production Units 3 and 6. MRB3, covering the Great Lakes, Ohio, Upper Mississippi, and Souris-Red-Rainy River basins, contains NHDPlus Production Units 4, 5, 7 and 9. MRB4, covering the Missouri River basins, contains NHDPlus Production Units 10-lower and 10-upper. MRB5, covering the Lower Mississippi, Arkansas-White-Red, and Texas-Gulf River basins, contains NHDPlus Production Units 8, 11 and 12. MRB6, covering the Rio Grande, Colorado and Great Basin River basins, contains NHDPlus Production Units 13, 14, 15 and 16. MRB7, covering the Pacific Northwest River basins, contains NHDPlus Production Unit 17. MRB8, covering California River basins, contains NHDPlus Production Unit 18.

Downstream Variation of Bankfull Geometry for the Continental and Overseas Hydro-Eco-Regions of France.

NASA Astrophysics Data System (ADS)

Tamisier, V.; Gob, F.; Thommeret, N.; Bilodeau, C.; Raufaste, S.; Kreutzenberger, K.

2016-12-01

Bankfull channel geometry is a fundamental and widely used concept in hydrology, fluvial geomorphology, and ecosystem studies. We develop and compare downstream hydraulic geometry relationships for bankfull channel width (w) and depth (d) as a function of drainage area A, respectively w=aAb (DHGwA) and d=cAf (DHGdA), for the 12 of the 21 French Hydro-Eco-Regions which are defined in terms of climate, topography and geology. The models have been built from a database (CARHYCE) that includes 1500 river reaches for which a unique standardized field protocol was used. River reach morphology was described based on a survey of 15 cross-sections spaced at intervals of one bankfull width. Sediment size and riverine vegetation were also measured and characterized. This database covers a wide range of French river diversity in terms of geomorphic types and anthropogenic impacts. Sampled stream reaches range from 1 to 70 000 km² in drainage area, 1 to 320 m in bankfull width and 0.3 to 8.5 m in bankfull depth. Approximately 500 poorly disturbed reaches were identified from several indices of disturbance at reach and basin scale (large dams, urbanization, channelization, etc.). For these reference sites, drainage areas display strong power-law relationships with both the width and the depth in most Hydro-Eco-Regions, with coefficients of determination (R²) ranging from 0.73 to 0.91 for DHGwA and from 0.57 to 0.77 for DHGdA (p-value < 0.001, t-test). The DHG exponent b and f ranges from 0.36 to 0.5 for DHGwA and from 0.21 to 0.3 for DHGdA. This implies that widths increase more strongly than depths with increasing drainage areas. The relative position of the models are compared to the national model and discussed with regard to the geologic, climatic and topographic characteristics. In Hydro-Eco-Regions which exhibit poor DHG relationships, the role of spatial variability in natural controls (climate, topography and geology) is discussed. Finally, reaches identified as potentially disturbed by human activities are compared to the reference models.

Survival and growth of restored Piedmont riparian forests as affected by site preparation, planting stock, and planting aids

Treesearch

Chelsea M. Curtis; W. Michael Aust; John R. Seiler; Brian D. Strahm

2015-01-01

Forest mitigation sites may have poor survival and growth of planted trees due to poor drainage, compacted soils, and lack of microtopography. The effects of five replications of five forestry mechanical site preparation techniques (Flat, Rip, Bed, Pit, and Mound), four regeneration sources (Direct seed, Bare root, Tubelings, and Gallon), and three planting aids (None...

Intrapericardial triamcinolone hexacetonide in the treatment of intractable uremic pericarditis in a child.

PubMed

Medani, C R; Ringel, R E

1988-01-01

Uremic pericarditis in children on chronic hemodialysis represents a difficult management problem, necessitating vigorous medical therapy and often surgical drainage of the pericardial effusion. Standard therapeutic approaches have met with limited success. The successful use of intrapericardial triamcinolone in a 10-year anephric boy on chronic dialysis is reported and accompanied by a description of the technique applied and literature review.

National Water-Quality Assessment (NAWQA) Area-Characterization Toolbox

USGS Publications Warehouse

Price, Curtis

2010-01-01

This is release 1.0 of the National Water-Quality Assessment (NAWQA) Area-Characterization Toolbox. These tools are designed to be accessed using ArcGIS Desktop software (versions 9.3 and 9.3.1). The toolbox is composed of a collection of custom tools that implement geographic information system (GIS) techniques used by the NAWQA Program to characterize aquifer areas, drainage basins, and sampled wells.

Pelvic drainage during removal of dialysis catheter decreases the risk of subsequent intra-abdominal complications in refractory peritoneal dialysis-related peritonitis.

PubMed

Hsu, Chih-Yang; Huang, Wei-Chieh; Huang, Chun-Kai; Huang, Chien-Wei; Chou, Nan-Hua; Lee, Po-Tsang; Fang, Hua-Chang; Chou, Kang-Ju; Chen, Chien-Liang

2015-11-01

Some patients with refractory peritoneal dialysis-related peritonitis continue to develop intra-abdominal complications despite removal of the peritoneal catheter. Repeated percutaneous drainage or open laparotomy is often required, and mortality is not uncommon. The benefits of pelvic drainage placement during catheter removal in decreasing these complications and interventions remain unproven. Forty-six patients with refractory peritonitis who underwent removal of a Tenckhoff catheter between 1991 and 2013 were reviewed retrospectively. Twelve patients had pelvic drainage using closed active suction devices during catheter removal (drainage group). The remaining 34 patients underwent catheter removal without drainage (non-drainage group). The outcomes measured were the development of intra-abdominal complications and the requirement for repeated percutaneous drainage or open laparotomy within 90 days after the catheter removal. Baseline characteristics were similar with the exception of a higher median number of previous peritonitis episodes in the drainage group compared with the non-drainage group (2 vs 0, P = 0.02). During the follow-up period, intra-abdominal complications occurred in 15 (44%) of 34 patients in the non-drainage group, compared with one (8%) of 12 patients in the drainage group (P = 0.03). Twelve (35%) patients in the non-drainage group required repeated percutaneous drainage or open laparotomy for management, compared with zero (0%) patients in the drainage group (P = 0.02). Drain tubes were removed at a median of 6 days (inter-quartile range: 5-10) without complications. In the management of refractory peritonitis, pelvic drainage during removal of dialysis catheter decreases the risk of subsequent intra-abdominal complications and invasive interventions. © 2015 Asian Pacific Society of Nephrology.

Evaluation of urban drainage network based geographycal information system (GIS) in Sumenep City

NASA Astrophysics Data System (ADS)

Agrianto, F.; Hadiani, R.; Purwana, Y. M.

2017-02-01

Sumenep City frequently hit by floods. Drainage network conditions greatly affect the performance of her maid, especially those aspects that affect the capacity of the drainage channel. Aspects that affect the capacity of the drainage channel in the form of sedimentation rate and complementary buildings on drainage channels, for example, the presence of street inlet and trash rack. The method used is a drainage channel capacity level approach that level assessment of each segment drainage network conditions by calculating the ratio of the channel cross-sectional area that is filled with sediment to the total cross-sectional area wet and the existence of complementary buildings. Having obtained the condition index value of each segment, the subsequent analysis is spatial analysis using ArcGIS applications to obtain a map of the drainage network information. The analysis showed that the level condition of drainage network in the city of Sumenep in 2016 that of the total 428 drainage network there are 43 sections belonging to the state level “Good”, 198 drainage network belong to the state level “Enough”, 115 drainage network belong to the state “Mild Damaged”, 50 sections belonging to the state “Heavy Damage” and 22 drainage network belong to the state of “Dysfunction”.

An Optimal Balance between Efficiency and Safety of Urban Drainage Networks

NASA Astrophysics Data System (ADS)

Seo, Y.

2014-12-01

Urban drainage networks have been developed to promote the efficiency of a system in terms of drainage time so far. Typically, a drainage system is designed to drain water from developed areas promptly as much as possible during floods. In this regard, an artificial drainage system have been considered to be more efficient compared to river networks in nature. This study examined artificial drainage networks and the results indicate they can be less efficient in terms of network configuration compared with river networks, which is counter-intuitive. The case study of 20 catchments in Seoul, South Korea shows that they have wide range of efficiency in terms of network configuration and consequently, drainage time. This study also demonstrates that efficient drainage networks are more sensitive to spatial and temporal rainfall variation such as rainstorm movement. Peak flows increase more than two times greater in effective drainage networks compared with inefficient and highly sinuous drainage networks. Combining these results, this study implies that the layout of a drainage network is an important factor in terms of efficient drainage and also safety in urban catchments. Design of an optimal layout of the drainage network can be an alternative non-structural measures that mitigate potential risks and it is crucial for the sustainability of urban environments.

In vitro genotoxic effect of secondary minerals crystallized in rocks from coal mine drainage.

PubMed

Nordin, Adriane Perachi; da Silva, Juliana; de Souza, Claudia Telles; Niekraszewicz, Liana A B; Dias, Johnny Ferraz; da Boit, Kátia; Oliveira, Marcos L S; Grivicich, Ivana; Garcia, Ana Letícia Hilario; Oliveira, Luis Felipe Silva; da Silva, Fernanda Rabaioli

2018-03-15

Coal processing generates a large volume of waste that can damage human health and the environment. Often these wastes produce acid drainage in which several minerals are crystallized (evaporites). This study aimed to identify secondary minerals, as well as the genotoxic potential of these materials. The samples were collected at two sites along the Rocinha River in Santa Catarina state (Brazil): (1) directly from the source of the acid drainage (evaporite 1), and (2) on the river bank (evaporite 2). The samples were characterized by X-ray diffraction and by particle-induced X-ray emission techniques. In vitro genotoxicity testing using Comet assay and Micronucleus test in V79 cells was used to evaluate evaporite samples. Our study also used System Biology tools to provide insight regarding the influence of this exposure on DNA damage in cells. The results showed that the samples induced DNA damage for both evaporites that can be explained by high concentrations of chromium, iron, nickel, copper and zinc in these materials. Thus, this study is very important due to the dearth of knowledge regarding the toxicity of evaporites in the environment. The genetic toxicity of this material can be induced by increased oxidative stress and DNA repair inhibition. Copyright © 2017 Elsevier B.V. All rights reserved.

Study of hydraulic properties of binary beads mixture as porous media in sustainable urban drainage system

NASA Astrophysics Data System (ADS)

Abdullah, Muhammad Faiz; Puay, How Tion; Zakaria, Nor Azazi

2017-10-01

Sustainable Urban Drainage System (SuDS) such as swales and rain gardens is showing growing popularity as a green technology for stormwater management and it can be used in all types of development to provide a natural approach to managing drainage. Soil permeability is a critical factor in selecting the right SuDS technique for a site. On this basis, we have set up a laboratory experiment to investigate the porosity and saturated hydraulic conductivity of single size and binary (two sizes) mixture using column-test as a preliminary investigation with two sets of glass beads with different sizes are used in this study. The porosity and saturated hydraulic conductivity for varies volume fraction of the course and fine glass beads were measured. It was found that the porosity of the binary mixture does not increase with the increment of the ratio of coarse to fine beads until the volume fraction of fine particles is equal to the coarse component. Saturated hydraulic conductivity result shows that the assumption of random packing was not achieved at the higher coarse ratio where most of the fine particles tend to sit at the bottom of the column forming separate layers which lower the overall hydraulic conductivity value.

Effects of Autogenic Drainage on Sputum Recovery and Pulmonary Function in People with Cystic Fibrosis: A Systematic Review.

PubMed

Morgan, Kimbly; Osterling, Kristin; Gilbert, Robert; Dechman, Gail

2015-01-01

To determine the effects of short- and long-term use of autogenic drainage (AD) on pulmonary function and sputum recovery in people with cystic fibrosis (CF). The authors conducted a systematic review of randomized and quasi-randomized clinical trials in which participants were people with CF who use AD as their sole airway clearance technique. Searches in 4 databases and secondary sources using 5 key terms yielded 735 articles, of which 58 contained the terms autogenic drainage and cystic fibrosis. Ultimately, 4 studies, 2 of which were long term, were included. All measured forced expiratory volume in 1 second (FEV1) and found no change. The long-term studies were underpowered to detect change in FEV1; however, the short-term studies found a clinically significant sputum yield (≥4 g). AD has been shown to produce clinically significant sputum yields in a limited number of investigations. The effect of AD on the function of the pulmonary system remains uncertain, and questions have emerged regarding the appropriateness of FEV1 as a valid measure of airway clearance from peripheral lung regions. Further consideration should be given to the use of FEV1 as a primary measure of the effect of AD.

Advances in endoscopic retrograde cholangiopancreatography for the treatment of cholangiocarcinoma

PubMed Central

Uppal, Dushant S; Wang, Andrew Y

2015-01-01

Cholangiocarcinoma (CCA) is a malignancy of the bile ducts that carries high morbidity and mortality. Patients with CCA typically present with obstructive jaundice, and associated complications of CCA include cholangitis and biliary sepsis. Endoscopic retrograde cholangiopancreatography (ERCP) is a valuable treatment modality for patients with CCA, as it enables internal drainage of blocked bile ducts and hepatic segments by using plastic or metal stents. While there remains debate as to if bilateral (or multi-segmental) hepatic drainage is required and/or superior to unilateral drainage, the underlying tenant of draining any persistently opacified bile ducts is paramount to good ERCP practice and good clinical outcomes. Endoscopic therapy for malignant biliary strictures from CCA has advanced to include ablative therapies via ERCP-directed photodynamic therapy (PDT) or radiofrequency ablation (RFA). While ERCP techniques cannot cure CCA, advancements in the field of ERCP have enabled us to improve upon the quality of life of patients with inoperable and incurable disease. ERCP-directed PDT has been used in lieu of brachytherapy to provide neoadjuvant local tumor control in patients with CCA who are awaiting liver transplantation. Lastly, mounting evidence suggests that palliative ERCP-directed PDT, and probably ERCP-directed RFA as well, offer a survival advantage to patients with this difficult-to-treat malignancy. PMID:26140095

Advances in endoscopic retrograde cholangiopancreatography for the treatment of cholangiocarcinoma.

PubMed

Uppal, Dushant S; Wang, Andrew Y

2015-06-25

Cholangiocarcinoma (CCA) is a malignancy of the bile ducts that carries high morbidity and mortality. Patients with CCA typically present with obstructive jaundice, and associated complications of CCA include cholangitis and biliary sepsis. Endoscopic retrograde cholangiopancreatography (ERCP) is a valuable treatment modality for patients with CCA, as it enables internal drainage of blocked bile ducts and hepatic segments by using plastic or metal stents. While there remains debate as to if bilateral (or multi-segmental) hepatic drainage is required and/or superior to unilateral drainage, the underlying tenant of draining any persistently opacified bile ducts is paramount to good ERCP practice and good clinical outcomes. Endoscopic therapy for malignant biliary strictures from CCA has advanced to include ablative therapies via ERCP-directed photodynamic therapy (PDT) or radiofrequency ablation (RFA). While ERCP techniques cannot cure CCA, advancements in the field of ERCP have enabled us to improve upon the quality of life of patients with inoperable and incurable disease. ERCP-directed PDT has been used in lieu of brachytherapy to provide neoadjuvant local tumor control in patients with CCA who are awaiting liver transplantation. Lastly, mounting evidence suggests that palliative ERCP-directed PDT, and probably ERCP-directed RFA as well, offer a survival advantage to patients with this difficult-to-treat malignancy.

Growth of the Pamir

NASA Astrophysics Data System (ADS)

Gloaguen, R.; Ratschbacher, L.

2009-04-01

We aim to establish the Late Cenozoic deformation field of the Pamir by localizing and characterizing active and neotectonic deformation structures, and setting up the drainage-basin, river-capture, river- reversal, and regional erosion history. The project thus aims to record the short-term, upper crustal response to active intra-continental subduction, orocline formation, and erosion. Our hypothesis is that the neotectonics is governed by subduction beneath the frontal part of the orocline, E-W extension in the intra-plateau Karakul-lake rift, and transtension (east) and transpression (west) along the lateral margins of the orocline, a result of oroclinal formation, rotation of the Indian indenter, and focused precipitation caused by the Westerlies. The model for the evolution of the drainage system involves: growth of the Pamir by N-ward propagating deformation, establishing E-trending belts of shortening and rivers/drainages; diversion and blocking of these rivers by the development of the lateral boundaries of the orocline that resulted in river capture and reversal. Even the present-day Panj (Amu Darya) is affected by ongoing uplift: tilted river terraces, wind gaps, and abnormal intersection of streams of different order indicate that large parts of the river have changed flow direction. The determination of a number of geomorphic indices with remote sensing techniques help us to identify areas experiencing tectonic deformation.

Sustainable rehabilitation of mining waste and acid mine drainage using geochemistry, mine type, mineralogy, texture, ore extraction and climate knowledge.

PubMed

Anawar, Hossain Md

2015-08-01

The oxidative dissolution of sulfidic minerals releases the extremely acidic leachate, sulfate and potentially toxic elements e.g., As, Ag, Cd, Cr, Cu, Hg, Ni, Pb, Sb, Th, U, Zn, etc. from different mine tailings and waste dumps. For the sustainable rehabilitation and disposal of mining waste, the sources and mechanisms of contaminant generation, fate and transport of contaminants should be clearly understood. Therefore, this study has provided a critical review on (1) recent insights in mechanisms of oxidation of sulfidic minerals, (2) environmental contamination by mining waste, and (3) remediation and rehabilitation techniques, and (4) then developed the GEMTEC conceptual model/guide [(bio)-geochemistry-mine type-mineralogy- geological texture-ore extraction process-climatic knowledge)] to provide the new scientific approach and knowledge for remediation of mining wastes and acid mine drainage. This study has suggested the pre-mining geological, geochemical, mineralogical and microtextural characterization of different mineral deposits, and post-mining studies of ore extraction processes, physical, geochemical, mineralogical and microbial reactions, natural attenuation and effect of climate change for sustainable rehabilitation of mining waste. All components of this model should be considered for effective and integrated management of mining waste and acid mine drainage. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effects of Autogenic Drainage on Sputum Recovery and Pulmonary Function in People with Cystic Fibrosis: A Systematic Review

PubMed Central

Osterling, Kristin; Gilbert, Robert; Dechman, Gail

2015-01-01

ABSTRACT Purpose: To determine the effects of short- and long-term use of autogenic drainage (AD) on pulmonary function and sputum recovery in people with cystic fibrosis (CF). Methods: The authors conducted a systematic review of randomized and quasi-randomized clinical trials in which participants were people with CF who use AD as their sole airway clearance technique. Results: Searches in 4 databases and secondary sources using 5 key terms yielded 735 articles, of which 58 contained the terms autogenic drainage and cystic fibrosis. Ultimately, 4 studies, 2 of which were long term, were included. All measured forced expiratory volume in 1 second (FEV1) and found no change. The long-term studies were underpowered to detect change in FEV1; however, the short-term studies found a clinically significant sputum yield (≥4 g). Conclusion: AD has been shown to produce clinically significant sputum yields in a limited number of investigations. The effect of AD on the function of the pulmonary system remains uncertain, and questions have emerged regarding the appropriateness of FEV1 as a valid measure of airway clearance from peripheral lung regions. Further consideration should be given to the use of FEV1 as a primary measure of the effect of AD. PMID:27504031

The role of interventional radiology in management of benign and malignant gynecologic diseases.

PubMed

Yu, Hyeon; Stavas, Joseph M

2013-10-01

This article focuses on the role of interventional radiology in the therapeutic and diagnostic management of benign and malignant gynecologic conditions. The subspecialty of interventional radiology utilizes minimally invasive advanced image-guided percutaneous techniques in gynecology that include central venous catheter placement, fluid aspiration, drainage catheter placement, tissue biopsy, inferior vena cava filter placement, and pelvic arterial embolization. Central venous catheters, such as ports, peripherally inserted central catheters, and tunneled catheters, are placed for intermediate to long-term intravenous chemotherapy or total parental nutrition or antibiotics. Patients with refractory malignant ascites or pleural effusion from seeding of advanced gynecologic cancers may benefit by percutaneous aspiration of fluid collections or placement of drainage catheters. Postoperative fluid collections including abscess, seroma, or lymphocele are managed by percutaneous drainage catheter insertion. Pelvic, peritoneal, or retroperitoneal masses can be sampled by image-guided percutaneous biopsy or aspiration of fluid to determine a pathologic diagnosis. Certain patients are at risk for deep venous thrombosis with pulmonary embolism and may benefit from an inferior vena cava filter. Patients with uncontrolled postoperative or postpartum bleeding can be effectively managed with emergent transarterial pelvic embolization. Each of the aforementioned interventions with indications, expected benefits, and complications is described including a published literature.

Partial anomalous pulmonary venous drainage. A novel approach to repair.

PubMed

Hanhan, U A; Moodie, D S; Gill, C C; Sterba, R; Currie, P; Stewart, R

1989-01-01

Isolated partial anomalous pulmonary venous drainage with an intact atrial septum is a rare finding. The authors describe their experience with three patients (ages 9, 37, and 54 years), with partial anomalous pulmonary venous connection to the superior vena cava, right atrium, and inferior vena cava, who underwent extracardiac conduit repair of this anomaly. In all three patients, a synthetic Gortex graft was used for reconstruction of the venous pathways to the left atrium. The follow-up period ranged from 10 to 82 months (mean, 42 months). All three patients were evaluated with intravenous digital angiography, transesophageal echocardiography, or both at 10, 33, and 82 months postoperatively. Patency of the grafts with no evidence of obstruction and excellent pulmonary venous flow was shown. This surgical technique is an excellent option for correction of this anomaly, and intravenous digital subtraction angiography is a useful diagnostic tool during the postoperative period to evaluate patency of the repair.

Review of pancreatic trauma.

PubMed Central

Glancy, K E

1989-01-01

In reviewing the literature on pancreatic trauma (1,984 cases), I found that it resulted from penetrating trauma in 73% and blunt trauma in 27% of cases. Associated injuries were common (average 3.0 per patient). Increased mortality was associated with shotgun wounds, an increasing number of associated injuries, the proximity of the injury to the head of the pancreas, preoperative shock, and massive hemorrhage. High mortality was found for total pancreatectomy, duct reanastomosis, and lack of surgical treatment, with lower mortality for Roux-en-Y anastomoses, suture and drainage, distal pancreatectomy, and duodenal exclusion and diverticulization techniques. Most patients required drainage only. The preoperative diagnosis of pancreatic trauma is difficult, with the diagnosis usually made during surgical repair for associated injuries. Blood studies such as amylase levels, diagnostic peritoneal lavage, and plain radiographs are not reliable. Computed tomographic scanning may be superior, but data are limited. PMID:2669347

The Suprachoroidal Route in Glaucoma Surgery

PubMed Central

Shaarawy, Tarek

2016-01-01

ABSTRACT Glaucoma surgeries targeting the uveoscleral drainage pathways have been drawing more attention lately. Among all the available techniques, procedures focusing on the supra-choroidal space seem particularly promising, by making use of a presumably efficient and secure outflow route and avoiding subconjunctival filtration blebs. The purpose of this review is to assess the efficacy and the security of the different suprachoroidal drainage implants, namely the CyPass Micro-Stent, the iStent Supra, the SOLX Gold Shunt, the Aquashunt, and the STARflo Glaucoma Implant. Most clinical studies seem to currently point toward the direction that there are actual benefits in suprachoroidal surgeries by avoiding bleb-related complications. Nevertheless, even suprachoroidal implants may be subject to scarring and failure. More data are still needed, especially concerning long-term effects, although the approach does seem appealing. How to cite this article: Gigon A, Shaarawy T. The Suprachoroidal Route in Glaucoma Surgery. J Curr Glaucoma Pract 2016;10(1): 13-20. PMID:27231415

Experimental techniques for studying the structure of foams and froths.

PubMed

Pugh, R J

2005-06-30

Several techniques are described in this review to study the structure and the stability of froths and foams. Image analysis proved useful for detecting structure changes in 2-D foams and has enabled the drainage process and the gradients in bubble size distribution to be determined. However, studies on 3-D foams require more complex techniques such as Multiple-Light Scattering Methods, Microphones and Optical Tomography. Under dynamic foaming conditions, the Foam Scan Column enables the water content of foams to be determined by conductivity analysis. It is clear that the same factors, which play a role in foam stability (film thickness, elasticity, etc.) also have a decisive influence on the stability of isolated froth or foam films. Therefore, the experimental thin film balance (developed by the Bulgarian Researchers) to study thinning of microfilms formed by a concave liquid drop suspended in a short vertical capillary tube has proved useful. Direct measurement of the thickness of the aqueous microfilm is determined by a micro-reflectance method and can give fundamental information on drainage and thin film stability. It is also important to consider the influence of the mineral particles on the stability of the froth and it have been shown that particles of well defined size and hydrophobicity can be introduced into the thin film enabling stabilization/destabilization mechanisms to be proposed. It has also been shown that the dynamic and static stability can be increased by a reduction in particle size and an increase in particle concentration.

Functional discrepancy between two liver lobes after hemilobe biliary drainage in patients with jaundice and bile duct cancer: an appraisal using (99m)Tc-GSA SPECT/CT fusion imaging.

PubMed

Sumiyoshi, Tatsuaki; Shima, Yasuo; Okabayashi, Takehiro; Noda, Yoshihiro; Hata, Yasuhiro; Murata, Yoriko; Kozuki, Akihito; Tokumaru, Teppei; Nakamura, Toshio; Uka, Kiminori

2014-11-01

To determine the functional discrepancy between the two liver lobes using technetium 99m ((99m)Tc) diethylenetriamine-pentaacetic acid-galactosyl human serum albumin ( GSA diethylenetriamine-pentaacetic acid-galactosyl human serum albumin ) single photon emission computed tomography (SPECT)/computed tomography (CT) fusion imaging following preoperative biliary drainage and portal vein embolization ( PVE portal vein embolization ) in patients with jaundice who have bile duct cancer ( BDC bile duct cancer ). This retrospective study was approved by the institutional review board, with waiver of informed consent. Preoperative (99m)Tc- GSA diethylenetriamine-pentaacetic acid-galactosyl human serum albumin SPECT/CT fusion images from 32 patients with extrahepatic BDC bile duct cancer were retrospectively reviewed. Patients were classified into four groups according to the extent of biliary drainage and presence of a preoperative right PVE portal vein embolization : right lobe drainage group (right drainage), bilateral lobe drainage group (bilateral drainage), left lobe drainage group (left drainage), and left lobe drainage with right PVE portal vein embolization group (left drainage with right PVE portal vein embolization ). Percentage volume and percentage function were measured in each lobe using fusion imaging. The ratio between percentage function and percentage volume (the function-to-volume ratio) was calculated for each lobe, and the results were compared among the four groups. Statistical analysis was performed with Wilcoxon signed-rank tests and Mann-Whitney U tests. The median values for the function-to-volume ratio in the right drainage, bilateral drainage, left drainage, and left drainage with right PVE portal vein embolization group were 1.12, 1.05, 1.02, and 0.81 in the right lobe; and 0.51, 0.88, 0.96, and 1.17 in the left lobe. Significant differences in the function-to-volume ratio were observed among the four groups (right drainage vs bilateral drainage vs left drainage vs left drainage with right PVE portal vein embolization ; with P < .002, P = .023, and P < .002 for the right lobe and P < .001, P = .023, and P < .002 for the left lobe). Hepatic lobar function significantly differs between the two lobes, depending on the extent of biliary drainage and the presence of portal vein embolization.

Modes of supraglacial lake drainage and dynamic ice sheet response

NASA Astrophysics Data System (ADS)

Das, S. B.; Behn, M. D.; Joughin, I. R.

2011-12-01

We investigate modes of supraglacial lake drainage using geophysical, ground, and remote sensing observations over the western margin of the Greenland ice sheet. Lakes exhibit a characteristic life cycle defined by a pre-drainage, drainage, and post-drainage phase. In the pre-drainage phase winter snow fills pre-existing cracks and stream channels, efficiently blocking past drainage conduits. As temperatures increase in the spring, surface melting commences, initially saturating the snow pack and subsequently forming a surface network of streams that fills the lake basins. Basins continue to fill until lake drainage commences, which for individual lakes occurs at different times depending on the previous winter snow accumulation and summer temperatures. Three styles of drainage behavior have been observed: (1) no drainage, (2) slow drainage over the side into an adjacent pre-existing crack, and (3) rapid drainage through a new crack formed beneath the lake basin. Moreover, from year-to-year individual lakes exhibit different drainage behaviors. Lakes that drain slowly often utilize the same outflow channel for multiple years, creating dramatic canyons in the ice. Ultimately, these surface channels are advected out of the lake basin and a new channel forms. In the post-drainage phase, melt water continues to access the bed typically through a small conduit (e.g. moulin) formed near a local topographic minimum along the main drainage crack, draining the lake catchment throughout the remainder of the melt season. This melt water input to the bed leads to continued basal lubrication and enhanced ice flow compared to background velocities. Lakes that do not completely drain freeze over to form a surface ice layer that persists into the following year. Our results show that supraglacial lakes show a spectrum of drainage behaviors and that these styles of drainage lead to varying rates and timing of surface meltwater delivery to the bed resulting in different dynamic ice responses.

Pawcatuck River and Narragansett Bay Drainage Basins Water and Related Land Resources Study. Big River Reservoir Project. Volume II. Appendix A-G.

DTIC Science & Technology

1981-07-01

01002 Director Mr. Frank Basile Mr. Paul Stang National Ocean Survey Bureau of Land Management Program Development & Policy U.S. Dept. of C6mmerce 6 World...construction. COMMENT: 2 There is no discussion on herbicides, pesticides , and fertilizers with fecal matter and nutrients that may have been used on...There is no discussion on herbicides, pesticides , and ferti- lizers with fecal matter and nutrients that may have been used on agricultural lands and

Active cycle of breathing technique for cystic fibrosis.

PubMed

Mckoy, Naomi A; Wilson, Lisa M; Saldanha, Ian J; Odelola, Olaide A; Robinson, Karen A

2016-07-05

People with cystic fibrosis experience chronic airway infections as a result of mucus build up within the lungs. Repeated infections often cause lung damage and disease. Airway clearance therapies aim to improve mucus clearance, increase sputum production, and improve airway function. The active cycle of breathing technique (also known as ACBT) is an airway clearance method that uses a cycle of techniques to loosen airway secretions including breathing control, thoracic expansion exercises, and the forced expiration technique. This is an update of a previously published review. To compare the clinical effectiveness of the active cycle of breathing technique with other airway clearance therapies in cystic fibrosis. We searched the Cochrane Cystic Fibrosis Trials Register, compiled from electronic database searches and handsearching of journals and conference abstract books. We also searched the reference lists of relevant articles and reviews.Date of last search: 25 April 2016. Randomised or quasi-randomised controlled clinical studies, including cross-over studies, comparing the active cycle of breathing technique with other airway clearance therapies in cystic fibrosis. Two review authors independently screened each article, abstracted data and assessed the risk of bias of each study. Our search identified 62 studies, of which 19 (440 participants) met the inclusion criteria. Five randomised controlled studies (192 participants) were included in the meta-analysis; three were of cross-over design. The 14 remaining studies were cross-over studies with inadequate reports for complete assessment. The study size ranged from seven to 65 participants. The age of the participants ranged from six to 63 years (mean age 22.33 years). In 13 studies, follow up lasted a single day. However, there were two long-term randomised controlled studies with follow up of one to three years. Most of the studies did not report on key quality items, and therefore, have an unclear risk of bias in terms of random sequence generation, allocation concealment, and outcome assessor blinding. Due to the nature of the intervention, none of the studies blinded participants or the personnel applying the interventions. However, most of the studies reported on all planned outcomes, had adequate follow up, assessed compliance, and used an intention-to-treat analysis.Included studies compared the active cycle of breathing technique with autogenic drainage, airway oscillating devices, high frequency chest compression devices, conventional chest physiotherapy, and positive expiratory pressure. Preference of technique varied: more participants preferred autogenic drainage over the active cycle of breathing technique; more preferred the active cycle of breathing technique over airway oscillating devices; and more were comfortable with the active cycle of breathing technique versus high frequency chest compression. No significant difference was seen in quality of life, sputum weight, exercise tolerance, lung function, or oxygen saturation between the active cycle of breathing technique and autogenic drainage or between the active cycle of breathing technique and airway oscillating devices. There was no significant difference in lung function and the number of pulmonary exacerbations between the active cycle of breathing technique alone or in conjunction with conventional chest physiotherapy. All other outcomes were either not measured or had insufficient data for analysis. There is insufficient evidence to support or reject the use of the active cycle of breathing technique over any other airway clearance therapy. Five studies, with data from eight different comparators, found that the active cycle of breathing technique was comparable with other therapies in outcomes such as participant preference, quality of life, exercise tolerance, lung function, sputum weight, oxygen saturation, and number of pulmonary exacerbations. Longer-term studies are needed to more adequately assess the effects of the active cycle of breathing technique on outcomes important for people with cystic fibrosis such as quality of life and preference.

Surgical treatment of chronic pancreatitis with pancreatic main duct dilatation: Long term results after head resection and duct drainage

PubMed Central

Schwarz, A.; Beger, H. G.

2005-01-01

Tissue and duct hypertension is considered as a major factor in the etiology of pain in patients with chronic pancreatitis (CP). Duct dilatation is a consequence of duct obstruction due to scars or duct stones. Nevertheless, the procedure of choice, drainage or resection, is still under discussion. We present long-term results of patients operated with duodenum-preserving pancreatic head resection (DPPHR) combined with a Partington-Rochelle duct drainage in cases of chronic pancreatitis with multiple stenosis and dilatation of the side ducts. Methods and patients. From April 1982 to September 2001, in 55 out of 538 patients with chronic pancreatitis, a DPPHR with additionally Partington-Rochelle duct drainage was performed (44 male, 11 female, mean age 45.8 years). Ninety-two percent of the patients suffered from alcoholic pancreatitis. Medical respective pain treatment for chronic pancreatitis was in median 64.5 months prior to surgery. The indications for surgery were in 87% pain, 59% of the patients had an inflammatory mass in the head of the pancreas, 36% a common bile duct stenosis and 5% a severe stenosis of the duodenum. The endocrine function (OGGT) was impaired in 79% of the patients preoperatively. Results. Hospital mortality was 0%, postoperative complications occurred in 11 patients. Follow-up: All except 2 patients were followed up in the outpatient clinic with the mean follow-up time of 69.7 months (8–105 months), the late mortality was 9%. Sixty-eight percent of the patients were completely free of pain, 29% had occasional pain, 3% suffered from a further attack of pancreatitis. Body weight increased in 79%, 58% were professionally rehabilitated. Late postoperative endocrine function was unchanged in 85% (improved in 5%, deteriorated in 10%). Conclusion. The pain control in patients with multiple duct stenosis after duodenum-preserving pancreatic head resection with duct drainage leads to long-standing absence of pain and low recurrence rate of attacks of pancreatitis. PMID:18333173

Sentinel lymph node mapping in breast cancer: a critical reappraisal of the internal mammary chain issue.

PubMed

Manca, G; Volterrani, D; Mazzarri, S; Duce, V; Svirydenka, A; Giuliano, A; Mariani, G

2014-06-01

Although, like the axilla, the internal mammary nodes (IMNs) are a first-echelon nodal drainage site in breast cancer, the importance of their treatment has long been debated. Seminal randomized trials have failed to demonstrate a survival benefit from surgical IMN dissection, and several retrospective studies have shown that IMNs are rarely the first site of recurrence. However, the recent widespread adoption of sentinel lymph node (SLN) biopsy has stimulated a critical reappraisal of such early results. Furthermore, the higher proportion of screening-detected cancers, improved imaging and techniques (i.e., lymphoscintigraphy for radioguided SLN biopsy) make it possible to visualize lymphatic drainage to the IMNs. The virtually systematic application of adjuvant systemic and/or loco-regional radiotherapy encourages re-examination of the significance of IMN metastases. Moreover, randomized trials testing the value of postmastectomy irradiation and a meta-analysis of 78 randomized trials have provided high levels of evidence that local-regional tumor control is associated with long-term survival improvements. This benefit was limited to trials that used systemic chemotherapy, which was not routinely administered in the earlier studies. However, the contribution from IMN treatment is unclear. Lymphoscintigraphic studies have shown that a significant proportion of breast cancers have primary drainage to the IMNs, including approximately 30% of medial tumors and 15% of lateral tumors. In the few studies where IMN biopsy was performed, 20% of sentinel IMNs were metastatic. The risk of IMN involvement is higher in patients with medial tumors and positive axillary nodes. IMN metastasis has prognostic significance, as recognized by its inclusion in the American Joint Committee on Cancer staging criteria, and seems to have similar prognostic importance as axillary nodal involvement. Although routine IMN evaluation might be indicated, it has not been routinely performed, perhaps because IMN drainage with lymphoscintigraphy is more difficult to demonstrate than axillary drainage. This difference is due to technical reasons and not the absence of lymphatics to the IMN. Recent anatomical studies have confirmed a model of breast lymphatic drainage that comprises superficial, deep and perforating systems. The superficial system drains to the axilla, usually to a lymph node posterior to the pectoralis minor muscle. The deep system drains to the axilla and also anastomoses with the perforating system which drains to the IMNs. The perforating system does not connect with the superficial system. The prevalence of IMN drainage tends to reflect the method of lymphoscintigraphy, where peritumoral (deep lymphatic system) injections have a much higher likelihood of IMN drainage than subareolar or subdermal (superficial lymphatic system) injections. The fused SPECT/CT images represent a further technical solution to increase the identification of IMNs and consequently can significantly reduce the false negative rate of sentinel lymph node biopsy. Before mature results from current and future randomized trials assessing the benefit of IMN irradiation become available, lymphoscintigraphy and IMNs biopsy may be used to guide decisions regarding systemic and local-regional treatment. However, even in patients with visualized primary IMN drainage, the potential benefit of treatment should be balanced against the risk of added morbidity.

Comparison between autologous blood transfusion drainage and closed-suction drainage/no drainage in total knee arthroplasty: a meta-analysis.

PubMed

Hong, Kun-Hao; Pan, Jian-Ke; Yang, Wei-Yi; Luo, Ming-Hui; Xu, Shu-Chai; Liu, Jun

2016-08-01

Autologous blood transfusion (ABT) drainage system is a new unwashed salvaged blood retransfusion system for total knee replacement (TKA). However, whether to use ABT drainage, closed-suction (CS) drainage or no drainage in TKA surgery remains controversial. This is the first meta-analysis to assess the clinical efficiency, safety and potential advantages regarding the use of ABT drains compared with closed-suction/no drainage. PubMed, Embase, and the Cochrane Library were comprehensively searched in March 2015. Fifteen randomized controlled trials (RCTs) were identified and pooled for statistical analysis. The primary outcome evaluated was homologous blood transfusion rate. The secondary outcomes were post-operative haemoglobin on days 3-5, length of hospital stay and wound infections after TKA surgery. The pooled data included 1,721 patients and showed that patients in the ABT drainage group might benefit from lower blood transfusion rates (16.59 % and 37.47 %, OR: 0.28 [0.14, 0.55]; 13.05 % and 16.91 %, OR: 0.73 [0.47,1.13], respectively). Autologous blood transfusion drainage and closed-suction drainage/no drainage have similar clinical efficacy and safety with regard to post-operative haemoglobin on days 3-5, length of hospital stay and wound infections. Autologous blood transfusion drainage offers a safe and efficient alternative to CS/no drainage with a lower blood transfusion rate. Future large-volume high-quality RCTs with extensive follow-up will affirm and update this system review.

The coupling between hydrodynamic and purification efficiencies of ecological porous spur-dike in field drainage ditch

NASA Astrophysics Data System (ADS)

Rao, Lei; Wang, Pei-fang; Dai, Qing-song; Wang, Chao

2018-05-01

In this study, a series of ecological porous spur-dikes are arranged in an experiment channel to simulate a real field drainage ditch. The inside and outside flow fields of spur-dikes are determined by numerical simulations and experimental methods. An Ammonia-Nitrogen (NH3-N) degradation evaluation model is built to calculate the pollution removal rate by coupling with the inner flow field of the porous spur-dikes. The variations of the total pollutant removal rate in the channel are discussed in terms of different porosities and gap distances between spur-dikes and inlet flow velocities. It is indicated that a reasonable parameter matching of the porosity and the gap distance with the flow velocity of the ditch can bring about a satisfactory purification efficiency with a small delivery quantity of ecological porous materials.

The Western Pond Turtle; Habitat and History, 1993-1994 Final Report.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Holland, Dan C.

1994-08-01

The western pond turtle is known from many areas of Oregon. The majority of sightings and other records occur in the major drainages of the Klamath, Rogue, Umpqua, Willamette and Columbia River systems. A brief overview is presented of the evolution of the Willamette-Puget Sound hydrographic basin. A synopsis is also presented of the natural history of the western pond turtle, as well as, the status of this turtle in the Willamette drainage basin. The reproductive ecology and molecular genetics of the western pond turtle are discussed. Aquatic movements and overwintering of the western pond turtle are evaluated. The effectmore » of introduced turtle species on the status of the western pond turtle was investigated in a central California Pond. Experiments were performed to determine if this turtle could be translocated as a mitigation strategy.« less

Water Quality in the Acadian-Pontchartrain Drainages; Louisiana and Mississippi, 1999-2001

USGS Publications Warehouse

Demcheck, Dennis K.; Tollett, Roland W.; Mize, Scott V.; Skrobialowski, Stanley C.; Fendick, Robert B.; Swarzenski, Christopher M.; Porter, Stephen

2004-01-01

This report contains the major findings of a 1999?2001 assessment of water quality in the Acadian-Pontchartrain Drainages Study Unit. It is one of a series of reports by the National Water-Quality Assessment (NAWQA) Program that present major findings in 51 major river basins and aquifer systems across the Nation. In these reports, water quality is discussed in terms of local, State, and regional issues. Conditions in a particular basin or aquifer system are compared to conditions found elsewhere and to selected national benchmarks, such as those for drinking-water quality and the protection of aquatic organisms. This report is intended for individuals working with water-resource issues in Federal, State, or local agencies, universities, public interest groups, or in the private sector. The information will be useful in addressing a number of current issues, such as the effects of agricultural and urban land use on water quality, human health, drinking water, source-water protection, hypoxia and excessive growth of algae and plants, pesticide registration, and monitoring and sampling strategies. This report also is for individuals who wish to know more about the quality of streams and ground water in areas near where they live, and how that water quality compares to other areas across the Nation. The water-quality conditions in the Acadian-Pontchartrain Drainages Study Unit summarized in this report are discussed in detail in other reports that can be accessed from (http://la.water.usgs.gov/nawqa/default.htm). Detailed technical information, data and analyses, collection and analytical methodology, models, graphs, and maps that support the findings presented in this report in addition to other reports in this series from other basins can be accessed from the national NAWQA Web site (http://water.usgs.gov/nawqa).

Reconstruction after retrosigmoid approaches using autologous fat graft-assisted Medpor Titan cranioplasty: assessment of postoperative cerebrospinal fluid leaks and headaches in 60 cases.

PubMed

Ling, Phoebe Y; Mendelson, Zachary S; Reddy, Rohit K; Jyung, Robert W; Liu, James K

2014-10-01

Postoperative cerebrospinal fluid (CSF) leaks and headaches remain potential complications after retrosigmoid approaches for lesions in the posterior fossa and cerebellopontine angle. The authors describe a simple repair technique with an autologous fat graft-assisted Medpor Titan cranioplasty and investigate the incidence of postoperative CSF leaks and headaches using this technique. A retrospective chart review was conducted on all cases (n = 60) of retrosigmoid craniectomy from September 2009 to May 2014 in patients who underwent fat graft-assisted cranioplasty. After obtaining a watertight dural closure and sealing off any visible mastoid air cells with bone wax, an autologous fat graft was placed over the dural suture line and up against the waxed-off air cells. The fat graft filled the retrosigmoid cranial defect and was then bolstered with a Medpor Titan (titanium mesh embedded in porous polyethylene) cranioplasty. A postoperative mastoid pressure dressing was applied for 48 h, and prophylactic lumbar drainage was not used. Factors examined in this study included postoperative CSF leak (incisional, rhinorrhea, otorrhea), pseudomeningocele formation, incidence and severity of postoperative headache, length of hospital stay, and length of follow-up. No patients developed postoperative CSF leaks (0 %), pseudomeningoceles (0 %), or new-onset postoperative headaches (0 %) with the described repair technique. There were no cases of graft site morbidity such as hematoma or wound infection. Mean duration of postoperative hospital stay was 3.8 days (range 2-10 days). Mean postoperative follow-up was 12.4 months (range 2.0-41.1 months). Our multilayer repair technique with a fat graft-assisted Medpor Titan cranioplasty appears effective in preventing postoperative CSF leaks and new-onset postoperative headaches after retrosigmoid approaches. Postoperative lumbar drainage may not be necessary.

Techniques for estimating flood-peak discharges from urban basins in Missouri

USGS Publications Warehouse

Becker, L.D.

1986-01-01

Techniques are defined for estimating the magnitude and frequency of future flood peak discharges of rainfall-induced runoff from small urban basins in Missouri. These techniques were developed from an initial analysis of flood records of 96 gaged sites in Missouri and adjacent states. Final regression equations are based on a balanced, representative sampling of 37 gaged sites in Missouri. This sample included 9 statewide urban study sites, 18 urban sites in St. Louis County, and 10 predominantly rural sites statewide. Short-term records were extended on the basis of long-term climatic records and use of a rainfall-runoff model. Linear least-squares regression analyses were used with log-transformed variables to relate flood magnitudes of selected recurrence intervals (dependent variables) to selected drainage basin indexes (independent variables). For gaged urban study sites within the State, the flood peak estimates are from the frequency curves defined from the synthesized long-term discharge records. Flood frequency estimates are made for ungaged sites by using regression equations that require determination of the drainage basin size and either the percentage of impervious area or a basin development factor. Alternative sets of equations are given for the 2-, 5-, 10-, 25-, 50-, and 100-yr recurrence interval floods. The average standard errors of estimate range from about 33% for the 2-yr flood to 26% for the 100-yr flood. The techniques for estimation are applicable to flood flows that are not significantly affected by storage caused by manmade activities. Flood peak discharge estimating equations are considered applicable for sites on basins draining approximately 0.25 to 40 sq mi. (Author 's abstract)

Keep wetlands wet: the myth of sustainable development of tropical peatlands - implications for policies and management.

PubMed

Evers, Stephanie; Yule, Catherine M; Padfield, Rory; O'Reilly, Patrick; Varkkey, Helena

2017-02-01

Pristine tropical peat swamp forests (PSFs) represent a unique wetland ecosystem of distinctive hydrology which support unique biodiversity and globally significant stores of soil carbon. Yet in Indonesia and Malaysia, home to 56% of the world's tropical peatland, they are subject to considerable developmental pressures, including widespread drainage to support agricultural needs. In this article, we review the ecology behind the functioning and ecosystem services provided by PSFs, with a particular focus on hydrological processes as well as the role of the forest itself in maintaining those services. Drawing on this, we review the suitability of current policy frameworks and consider the efficacy of their implementation. We suggest that policies in Malaysia and Indonesia are often based around the narrative of oil palm and other major monocrops as drivers of prosperity and development. However, we also argue that this narrative is also being supported by a priori claims concerning the possibility of sustainability of peat swamp exploitation via drainage-based agriculture through the adherence to best management practices. We discuss how this limits their efficacy, uptake and the political will towards enforcement. Further, we consider how both narratives (prosperity and sustainability) clearly exclude important considerations concerning the ecosystem value of tropical PSFs which are dependent on their unimpacted hydrology. Current research clearly shows that the actual debate should be focused not on how to develop drainage-based plantations sustainably, but on whether the sustainable conversion to drainage-based systems is possible at all. © 2016 John Wiley & Sons Ltd.

Geodatabase of sites, basin boundaries, and topology rules used to store drainage basin boundaries for the U.S. Geological Survey, Colorado Water Science Center

USGS Publications Warehouse

Dupree, Jean A.; Crowfoot, Richard M.

2012-01-01

This geodatabase and its component datasets are part of U.S. Geological Survey Digital Data Series 650 and were generated to store basin boundaries for U.S. Geological Survey streamgages and other sites in Colorado. The geodatabase and its components were created by the U.S. Geological Survey, Colorado Water Science Center, and are used to derive the numeric drainage areas for Colorado that are input into the U.S. Geological Survey's National Water Information System (NWIS) database and also published in the Annual Water Data Report and on NWISWeb. The foundational dataset used to create the basin boundaries in this geodatabase was the National Watershed Boundary Dataset. This geodatabase accompanies a U.S. Geological Survey Techniques and Methods report (Book 11, Section C, Chapter 6) entitled "Digital Database Architecture and Delineation Methodology for Deriving Drainage Basins, and Comparison of Digitally and Non-Digitally Derived Numeric Drainage Areas." The Techniques and Methods report details the geodatabase architecture, describes the delineation methodology and workflows used to develop these basin boundaries, and compares digitally derived numeric drainage areas in this geodatabase to non-digitally derived areas. 1. COBasins.gdb: This geodatabase contains site locations and basin boundaries for Colorado. It includes a single feature dataset, called BasinsFD, which groups the component feature classes and topology rules. 2. BasinsFD: This feature dataset in the "COBasins.gdb" geodatabase is a digital container that holds the feature classes used to archive site locations and basin boundaries as well as the topology rules that govern spatial relations within and among component feature classes. This feature dataset includes three feature classes: the sites for which basins have been delineated (the "Sites" feature class), basin bounding lines (the "BasinLines" feature class), and polygonal basin areas (the "BasinPolys" feature class). The feature dataset also stores the topology rules (the "BasinsFD_Topology") that constrain the relations within and among component feature classes. The feature dataset also forces any feature classes inside it to have a consistent projection system, which is, in this case, an Albers-Equal-Area projection system. 3. BasinsFD_Topology: This topology contains four persistent topology rules that constrain the spatial relations within the "BasinLines" feature class and between the "BasinLines" feature class and the "BasinPolys" feature classes. 4. Sites: This point feature class contains the digital representations of the site locations for which Colorado Water Science Center basin boundaries have been delineated. This feature class includes point locations for Colorado Water Science Center active (as of September 30, 2009) gages and for other sites. 5. BasinLines: This line feature class contains the perimeters of basins delineated for features in the "Sites" feature class, and it also contains information regarding the sources of lines used for the basin boundaries. 6. BasinPolys: This polygon feature class contains the polygonal basin areas delineated for features in the "Sites" feature class, and it is used to derive the numeric drainage areas published by the Colorado Water Science Center.

CUA Annual Meeting Abstracts addition.

PubMed

2012-08-01

: Foley catheters are assumed to drain the bladder to completion. We have previously shown that dependent loops along the drainage tubing create air-locks, which obstruct antegrade urine flow and result in un-drained residual bladder urine. We hypothesized that drainage characteristics of Foley catheters remain poorly understood by urologists and general surgeons. We conducted a nationwide survey of general surgery and urology training program faculty and residents, to assess perceptions of Foley catheter drainage. We designed a novel catheter drainage tube/bag that eliminates air-locks. : An anonymous illustrated questionnaire assessing Foley catheter use patterns and perception was sent to general surgery and urology residency programs (N=108) nationwide. A modified catheter drainage tube/bag unit was designed and tested. An ex vivo catheterized bladder model was designed to measure and compare urine drainage rates with the standard drainage system, versus with our novel design. : A total of 307 responses were collected from residents (55%) and faculty (45%); responses were similar among both groups (p<0.05). The majority reported that at their centers Foley catheter drainage tubes are generally positioned with a dependent loop (94.1%), and, that positioning with a dependent loop, versus without (78.1%) promoted optimal drainage. Antegrade drainage does not occur with a traditional drainage system when a >5.5 inch dependent loop in place. With our proposed design, which eliminates dependent loops, the bladder model emptied to completion consistently. : Traditional Foley catheter drainage systems, as commonly used, evacuate the bladder sub- optimally. More reliable and complete bladder drainage may decrease the incidence of catheter related UTI. The novel modified Foley catheter drainage tube/bag design presented here eliminates dependent loops, to optimize antegrade drainage.

Application of BIM Technology in Building Water Supply and Drainage Design

NASA Astrophysics Data System (ADS)

Wei, Tianyun; Chen, Guiqing; Wang, Junde

2017-12-01

Through the application of BIM technology, the idea of building water supply and drainage designers can be related to the model, the various influencing factors to affect water supply and drainage design can be considered more comprehensively. BIM(Building information model) technology assist in improving the design process of building water supply and drainage, promoting the building water supply and drainage planning, enriching the building water supply and drainage design method, improving the water supply and drainage system design level and building quality. Combined with fuzzy comprehensive evaluation method to analyze the advantages of BIM technology in building water supply and drainage design. Therefore, application prospects of BIM technology are very worthy of promotion.

Spontaneous esophageal-pleural fistula

PubMed Central

Vyas, Sameer; Prakash, Mahesh; Kaman, Lileshwar; Bhardwaj, Nidhi; Khandelwal, Niranjan

2011-01-01

Spontaneous esophageal-pleural fistula (EPF) is a rare entity. We describe a case in a middle-aged female who presented with severe retrosternal chest pain and shortness of breadth. Chest computed tomography showed right EPF and hydropneumothorax. She was managed conservatively keeping the chest tube drainage and performing feeding jejunostomy. A brief review of the imaging finding and management of EPF is discussed. PMID:22084548

Influence of forest and rangeland management on anadromous fish habitat in Western North America: planning forest roads to protect salmonid habitat.

Treesearch

Carlton S. Yee; Terry D. Roelofs

1980-01-01

The construction and existence of forest roads, landings, and decking areas may have significant effects on anadromous fish habitat . Major effects discussed in this paper are increased sedimentation from transportation networks, the hindrance to fish migration of drainage structures, and possible changes in water quality from road stabilization additives. Guidelines...

Exploring Agricultural Drainage's Influence on Wetland and ...

EPA Pesticide Factsheets

Artificial agricultural drainage (i.e. surface ditches or subsurface tile) is an important agricultural management tool. Artificial drainage allows for timely fieldwork and adequate root aeration, resulting in greater crop yields for farmers. This practice is widespread throughout many regions of the United States and the network of artificial drainage is especially extensive in flat, poorly-drained regions like the glaciated Midwest. While beneficial for crop yields, agricultural drains often empty into streams within the natural drainage system. The increased network connectivity may lead to greater contributing area for watersheds, altered hydrology and increased conveyance of pollutants into natural water bodies. While studies and models at broader scales have implicated artificial drainage as an important driver of hydrological shifts and eutrophication, the actual spatial extent of artificial drainage is poorly known. Consequently, metrics of wetland and watershed connectivity within agricultural regions often fail to explicitly include artificial drainage. We use recent agricultural census data, soil drainage data, and land cover data to create estimates of potential agricultural drainage across the United States. We estimate that agricultural drainage in the US is greater than 31 million hectares and is concentrated in the upper Midwest Corn Belt, covering greater than 50% of available land for 114 counties. Estimated drainage values for numerous countie

[Clinical application of self-made drainage tube with balloon for iatrogenic colonic perforation].

PubMed

Liu, Bing-rong; Li, Hui; Zhao, Li-xia; Song, Ji-tao; Wang, Yan-jun; Chen, Jing; Liu, Wei

2012-07-01

To investigate the clinical efficacy of colonic bypass drainage by self-made drainage tube with balloon for iatrogenic colonic perforation. A retrospective analysis of 8 patients with iatrogenic colonic perforations from January 2009 to March 2011 was performed. Self-made drainage tubes with balloon were placed in the bowel lumen endoscopically after perforations were closed with endoclips or endoloops under endoscope. The inflatable balloon at the front-end of the tube was fixed at the mouth side of colonic perforation to achieve continuous drainage of stool and intestinal juice. Endoscopic bypass continuous drainage by using self-made drainage tube with balloon was successfully carried out in all the 8 patients. All the perforations healed and no surgical intervention required. Bypass drainage continued for 3-10 days(mean 7.6 days). One patient received colonoscopy 3 days after the procedure, and displacement of the drainage tube was noticed requiring endoscopic adjustment. All the drainage tubes were removed uneventfully, and no ulceration or perforation occurred at balloon fixed site after removal. After follow up ranging from 12 to 36 months, no chronic fistula, adhesive obstruction, or abdominal infection occurred. Colonic bypass drainage by self-made drainage tube with balloon for iatrogenic colonic perforation is simple, feasible, safe and reliable.

Distributed acoustic sensing technique and its field trial in SAGD well

NASA Astrophysics Data System (ADS)

Han, Li; He, Xiangge; Pan, Yong; Liu, Fei; Yi, Duo; Hu, Chengjun; Zhang, Min; Gu, Lijuan

2017-10-01

Steam assisted gravity drainage (SAGD) is a very promising way for the development of heavy oil, extra heavy oil and tight oil reservoirs. Proper monitoring of the SAGD operations is essential to avoid operational issues and improve efficiency. Among all the monitoring techniques, micro-seismic monitoring and related interpretation method can give useful information about the steam chamber development and has been extensively studied. Distributed acoustic sensor (DAS) based on Rayleigh backscattering is a newly developed technique that can measure acoustic signal at all points along the sensing fiber. In this paper, we demonstrate a DAS system based on dual-pulse heterodyne demodulation technique and did field trial in SAGD well located in Xinjiang Oilfield, China. The field trail results validated the performance of the DAS system and indicated its applicability in steam-chamber monitoring and hydraulic monitoring.

Traditional Foley drainage systems--do they drain the bladder?

PubMed

Garcia, Maurice M; Gulati, Shelly; Liepmann, Dorian; Stackhouse, G Bennett; Greene, Kirsten; Stoller, Marshall L

2007-01-01

Foley catheters are assumed to drain the bladder to completion. Drainage characteristics of Foley catheter systems are poorly understood. To investigate unrecognized retained urine with Foley catheter drainage systems, bladder volumes of hospitalized patients were measured with bladder scan ultrasound volumetrics. Additionally, an in vitro bench top mock bladder and urinary catheter system was developed to understand the etiology of such residual volumes. A novel drainage tube design that optimizes indwelling catheter drainage was also designed. Bedside bladder ultrasound volumetric studies were performed on patients hospitalized in ward and intensive care unit. If residual urine was identified the drainage tubing was manipulated to facilitate drainage. An ex vivo bladder-urinary catheter model was designed to measure flow rates and pressures within the drainage tubing of a traditional and a novel drainage tube system. A total of 75 patients in the intensive care unit underwent bladder ultrasound volumetrics. Mean residual volume was 96 ml (range 4 to 290). In 75 patients on the hospital ward mean residual volume was 136 ml (range 22 to 647). In the experimental model we found that for every 1 cm in curl height, obstruction pressure increased by 1 cm H2O within the artificial bladder. In contrast, the novel spiral-shaped drainage tube demonstrated rapid (0.5 cc per second), continuous and complete (100%) reservoir drainage in all trials. Traditional Foley catheter drainage systems evacuate the bladder suboptimally. Outflow obstruction is caused by air-locks that develop within curled redundant drainage tubing segments. The novel drainage tubing design eliminates gravity dependent curls and associated air-locks, optimizes flow, and minimizes residual bladder urine.

Lessons learned from a randomized trial of airway secretion clearance techniques in cystic fibrosis

PubMed Central

Sontag, Marci K.; Quittner, Alexandra L.; Modi, Avani C.; Koenig, Joni M.; Giles, Don; Oermann, Christopher M.; Konstan, Michael W.; Castile, Robert; Accurso, Frank J.

2014-01-01

Rationale Airway secretion clearance therapies are a cornerstone of cystic fibrosis care, however longitudinal comparative studies are rare. Our objectives were to compare three therapies [postural drainage and percussion: (postural drainage), flutter device, and high frequency chest wall oscillation: (vest)], by studying 1) change in pulmonary function; 2) time to need for IV antibiotics, 3) use of pulmonary therapies, 4) adherence to treatment, 5) treatment satisfaction, and 6) quality of life. Methods Participants were randomly assigned to one of three therapies twice daily. Clinical outcomes were assessed quarterly over 3 years. Results Enrollment goals were not met, and withdrawal rates were high, especially in postural drainage (51%) and flutter device (26%), compared to vest (9%), resulting in early termination. FEV1 decline, time to need IV antibiotics, and other pulmonary therapies were not different. The annual FEF25–75% predicted rate of decline was greater in those using vest (p=0.02). Adherence was not significantly different (p=0.09). Overall treatment satisfaction was higher in vest and flutter device than in postural drainage (p<0.05). Health-related quality of life was not different. The rate of FEV1 decline was 1.23% predicted/year. Conclusions The study was ended early due to dropout and smaller than expected decline in FEV1. Patients were more satisfied with vest and flutter device. The longitudinal decline in FEF25–75% was faster in vest; we found no other difference in lung function decline, taken together this warrants further study. The slow decline in FEV1 illustrates the difficulty with FEV1 decline as a clinical trial outcome. PMID:20146387

Management of Postoperative Lymphoceles After Lymphadenectomy: Percutaneous Catheter Drainage With and Without Povidone-Iodine Sclerotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Alago, William, E-mail: alagow@mskcc.org; Deodhar, Ajita; Michell, Hans

To report our single-center experience in managing symptomatic lymphoceles after lymphadenectomy for genitourinary and gynecologic malignancy and to compare clinical outcomes of percutaneous catheter drainage (PCD) alone versus PCD with transcatheter povidone-iodine sclerotherapy (TPIS). The medical records of patients who presented for percutaneous drainage of pelvic lymphoceles from February 1999 to September 2007 were retrospectively reviewed. Catheters with prolonged outputs >50 cc/day were treated with TPIS. Technical success was defined as the ability to achieve complete resolution of the lymphocele. Clinical success was defined as resolution of the patient's symptoms that prompted the intervention. Sixty-four patients with 70 pelvic lymphocelesmore » were treated. Forty-six patients (71.9 %) had PCD, and 18 patients (28.1 %) had multisession TPIS. The mean initial cavity size was 294.9 cc for those treated with TPIS and 228.2 cc for those treated with PCD alone (range 15-1,600) (p = 0.59). Mean duration of catheter drainage was 19 days (29 days with TPIS, 16 days with PCD, p = 0.001). Mean clinical follow-up was 22.6 months. Technical success was 74.3 % with PCD and 100 % with TPIS. Clinical success was 97 % with PCD and 100 % with TPIS. Postprocedural complications included pericatheter fluid leakage (n = 4), catheter dislodgement (n = 3), catheter occlusion (n = 9), and secondary infection of the collection (n = 4). PCD of symptomatic lymphoceles is an effective postoperative management technique. Initial cavity size is not an accurate predictor of the need for TPIS. When indicated, TPIS is safe and effective with catheter outputs >50 cc/day.« less

Imaging Preferential Flow Pathways of Contaminants from Passive Acid Mine Drainage Mitigation Sites Using Electrical Resistivity

NASA Astrophysics Data System (ADS)

Kelley, N.; Mount, G.; Terry, N.; Herndon, E.; Singer, D. M.

2017-12-01

The Critical Zone represents the surficial and shallow layer of rock, air, water, and soil where most interactions between living organisms and the Earth occur. Acid mine drainage (AMD) resulting from coal extraction can influence both biological and geochemical processes across this zone. Conservative estimates suggest that more than 300 million gallons of AMD are released daily, making this acidic solution of water and contaminants a common issue in areas with legacy or current coal extraction. Electrical resistivity imaging (ERI) provides a rapid and minimally invasive method to identify and monitor contaminant pathways from AMD remediation systems in the subsurface of the Critical Zone. The technique yields spatially continuous data of subsurface resistivity that can be inverted to determine electrical conductivity as a function of depth. Since elevated concentrations of heavy metals can directly influence soil conductivity, ERI data can be used to trace the flow pathways or perhaps unknown mine conduits and transport of heavy metals through the subsurface near acid mine drainage sources. This study aims to examine preferential contaminant migration from those sources through substrate pores, fractures, and shallow mine workings in the near subsurface surrounding AMD sites in eastern Ohio and western Pennsylvania. We utilize time lapse ERI measures during different hydrologic conditions to better understand the variability of preferential flow pathways in relation to changes in stage and discharge within the remediation systems. To confirm ERI findings, and provide constraint to geochemical reactions occurring in the shallow subsurface, we conducted Inductively Coupled Plasma (ICP) spectrometry analysis of groundwater samples from boreholes along the survey transects. Through these combined methods, we can provide insight into the ability of engineered systems to contain and isolate metals in passive acid mine drainage treatment systems.

Synthesis of natural flows at selected sites in and near the Milk River basin, Montana, 1928-89

USGS Publications Warehouse

Cary, L.E.; Parrett, Charles

1995-01-01

Natural monthly streamflows were synthesized for the years 1928-89 at 2 sites in the St. Mary River Basin and 11 sites in the Milk River Basin in north- central Montana. The sites are represented as nodes in a streamflow accounting model being developed by the Bureau of Reclamation for the Milk River Basin. Recorded flows at most sites have been affected by human activities, including reservoir storage and irrigation diversions. The flows at the model nodes were corrected for the effects of these activities to obtain synthesized flows. The synthesized flows at nodes with seasonal and short-term records were extended using a statistical technique. The methods of synthesis varied, depending on upstream activities and information available. Flows at sites in the St. Mary River Basin and at the Milk River at Eastern Crossing of International Boundary pre- viously had been synthesized. The flows at mainstem sites downstream from the Milk River at Eastern Crossing were synthesized by adding synthesized natural runoff from intervening drainage areas to natural flows for Milk River at Eastern Crossing. Natural runoff from intervening drainage areas was estimated by multiplying recorded flows at selected index gaging stations on tributary streams by the ratio of the intervening drainage area to the combined drainage area of the index stations. The recorded flows for Milk River at Western Crossing of International Boundary and for Peoples Creek near Dodson, Montana, were assumed to be natural flows. The synthesized annual flows at the mouth of the Milk River compared favorably with the recorded flows near the mouth when the effects of upstream irrigation were considered.

Tile drainage as karst: Conduit flow and diffuse flow in a tile-drained watershed

USGS Publications Warehouse

Schilling, K.E.; Helmers, M.

2008-01-01

The similarity of tiled-drained watersheds to karst drainage basins can be used to improve understanding of watershed-scale nutrient losses from subsurface tile drainage networks. In this study, short-term variations in discharge and chemistry were examined from a tile outlet collecting subsurface tile flow from a 963 ha agricultural watershed. Study objectives were to apply analytical techniques from karst springs to tile discharge to evaluate water sources and estimate the loads of agricultural pollutants discharged from the tile with conduit, intermediate and diffuse flow regimes. A two-member mixing model using nitrate, chloride and specific conductance was used to distinguish rainwater versus groundwater inputs. Results indicated that groundwater comprised 75% of the discharge for a three-day storm period and rainwater was primarily concentrated during the hydrograph peak. A contrasting pattern of solute concentrations and export loads was observed in tile flow. During base flow periods, tile flow consisted of diffuse flow from groundwater sources and contained elevated levels of nitrate, chloride and specific conductance. During storm events, suspended solids and pollutants adhered to soil surfaces (phosphorus, ammonium and organic nitrogen) were concentrated and discharged during the rapid, conduit flow portion of the hydrograph. During a three-day period, conduit flow occurred for 5.6% of the time but accounted for 16.5% of the total flow. Nitrate and chloride were delivered primarily with diffuse flow (more than 70%), whereas 80-94% of total suspended sediment, phosphorus and ammonium were exported with conduit and intermediate flow regimes. Understanding the water sources contributing to tile drainage and the manner by which pollutant discharge occurs from these systems (conduit, intermediate or diffuse flow) may be useful for designing, implementing and evaluating non-point source reduction strategies in tile-drained landscapes. ?? 2007 Elsevier B.V. All rights reserved.

The precipitation of aluminum, iron and manganese at the junction of Deer Creek with the Snake River in Summit County, Colorado

USGS Publications Warehouse

Theobald, P.K.; Lakin, H.W.; Hawkins, D.B.

1963-01-01

The oxidation of disseminated pyrite in relatively acid schists and gneisses of the Snake River drainage basin provides abundant iron sulfate and sulfuric acid to ground and surface water. This acid water dissolves large quantities of many elements, particularly aluminum and surprisingly large quantities of elements, such as magnesium and zinc, not expected to be abundant in the drainage basin. The adjoining drainage to the west, Deer Creek, is underlain by basic rocks, from which the water inherits a high pH. Despite the presence of base- and precious- metal veins in the drainage basin of Deer Creek, it carries less metal than the Snake River. The principal precipitate on the bed of the Snake River is hydrated iron oxide with small quantities of the other metals. In Deer Creek manganese oxide is precipitated with iron oxide and large quantities of other metals are carried down with this precipitate. Below the junction of these streams the pH stabilizes at a near-neutral value. Iron is removed from the Snake River water at the junction, and aluminum is precipitated for some distance downstream. The aluminum precipitate carries down other metals in concentrations slightly less than that in the manganese precipitate on Deer Creek. The natural processes observed in this junction if carried to a larger scale could provide the mechanism described by Ansheles (1927) for the formation of bauxite. In the environment described, geochemical exploration by either water or stream sediment techniques is difficult because of (1) the extreme pH differential between the streams above their junction and (2) the difference in the precipitates formed on the streambeds. ?? 1963.

Meta-image navigation augmenters for GPS denied mountain navigation of small UAS

NASA Astrophysics Data System (ADS)

Wang, Teng; ćelik, Koray; Somani, Arun K.

2014-06-01

We present a novel approach to use mountain drainage patterns for GPS-Denied navigation of small unmanned aerial systems (UAS) such as the ScanEagle, utilizing a down-looking fixed focus monocular imager. Our proposal allows extension of missions to GPS-denied mountain areas, with no assumption of human-made geographic objects. We leverage the analogy between mountain drainage patterns, human arteriograms, and human fingerprints, to match local drainage patterns to Graphics Processing Unit (GPU) rendered parallax occlusion maps of geo-registered radar returns (GRRR). Details of our actual GPU algorithm is beyond the subject of this paper, and is planned as a future paper. The matching occurs in real-time, while GRRR data is loaded on-board the aircraft pre-mission, so as not to require a scanning aperture radar during the mission. For recognition purposes, we represent a given mountain area with a set of spatially distributed mountain minutiae, i.e., details found in the drainage patterns, so that conventional minutiae-based fingerprint matching approaches can be used to match real-time camera image against template images in the training set. We use medical arteriography processing techniques to extract the patterns. The minutiae-based representation of mountains is achieved by first exposing mountain ridges and valleys with a series of filters and then extracting mountain minutiae from these ridges/valleys. Our results are experimentally validated on actual terrain data and show the effectiveness of minutiae-based mountain representation method. Furthermore, we study how to select landmarks for UAS navigation based on the proposed mountain representation and give a set of examples to show its feasibility. This research was in part funded by Rockwell Collins Inc.

Plastic (wire-combed) grooving of a slip-formed concrete runway overlay at Patrick Henry Airport: An initial evaluation

NASA Technical Reports Server (NTRS)

Marlin, E. C.; Horne, W. B.

1977-01-01

A wire-comb technique is described for transversely grooving the surface of a freshly laid (plastic state) slip-formed concrete overlay installed at Patrick Henry Airport. This method of surface texturing yields better water drainage and pavement skid resistance than that obtained with an older conventional burlap drag concrete surface treatment installed on an adjacent portion of the runway.

Bundle of measures for external cerebral ventricular drainage-associated ventriculitis.

PubMed

Chatzi, Maria; Karvouniaris, Marios; Makris, Demosthenes; Tsimitrea, Eleni; Gatos, Charalampos; Tasiou, Anastasia; Mantzarlis, Kostas; Fountas, Kostas N; Zakynthinos, Epaminondas

2014-01-01

To assess the prevalence and outcome of external cerebral ventricular drainage-associated ventriculitis in neurocritical patients before and after the implementation of a bundle of external cerebral ventricular drainage-associated ventriculitis control measures. Clinical prospective case series. University Hospital of Larissa, Greece. Consecutive patients were recruited from the ICU of the hospital. Patient inclusion criteria included presence of external ventricular drainage and ICU stay more than 48 hours. The bundle of external cerebral ventricular drainage-associated ventriculitis control measures included 1) reeducation of ICU personnel on issues of infection control related to external cerebral ventricular drainage, 2) meticulous intraventricular catheter handling, 3) cerebrospinal fluid sampling only when clinically necessary, and 4) routine replacement of the drainage catheter on the seventh drainage day if the catheter was still necessary. The bundle was applied after an initial period (preintervention) where standard policy for external cerebral ventricular drainage-associated ventriculitis was established. External cerebral ventricular drainage-associated ventriculitis prevalence, external cerebral ventricular drainage-associated ventriculitis events per 1,000 drainage days (drain-associated infection rate), length of ICU stay, Glasgow Outcome Scale at 6 months, and risk factors for external cerebral ventricular drainage-associated ventriculitis. Eighty-two patients entered the study in the preintervention period and 57 patients during the intervention period. During the preintervention and intervention period, external cerebral ventricular drainage-associated ventriculitis prevalence was 28% and 10.5% (p = 0.02) and drain-associated infection rate was 18 and 7.1, respectively (p = 0.0001); mean (95% CI) length of ICU stay in patients who presented external cerebral ventricular drainage-associated ventriculitis was 44.4 days (36.4-52.4 d), whereas mean (95% CI) length of ICU stay in patients who did not was 20 days (16.9-23.2 d) (p < 0.001). Furthermore, the length of ICU stay was associated with length of drainage (p = 0.0001). Therefore, the presence of external cerebral ventricular drainage-associated ventriculitis and the length of drainage were the only variables associated with a prolonged ICU stay. Unfavorable outcome in Glasgow Outcome Scale at 6 months was not associated with the presence of external cerebral ventricular drainage-associated ventriculitis (p = 0.5). No significant differences were found when Glasgow Outcome Scale was analyzed according to the two study periods. The implementation of a bundle of measures for external cerebral ventricular drainage-associated ventriculitis control was associated with significantly decreased postintervention prevalence of the infection.

Techniques for estimating selected streamflow characteristics of rural unregulated streams in Ohio

USGS Publications Warehouse

Koltun, G.F.; Whitehead, Matthew T.

2002-01-01

This report provides equations for estimating mean annual streamflow, mean monthly streamflows, harmonic mean streamflow, and streamflow quartiles (the 25th-, 50th-, and 75th-percentile streamflows) as a function of selected basin characteristics for rural, unregulated streams in Ohio. The equations were developed from streamflow statistics and basin-characteristics data for as many as 219 active or discontinued streamflow-gaging stations on rural, unregulated streams in Ohio with 10 or more years of homogenous daily streamflow record. Streamflow statistics and basin-characteristics data for the 219 stations are presented in this report. Simple equations (based on drainage area only) and best-fit equations (based on drainage area and at least two other basin characteristics) were developed by means of ordinary least-squares regression techniques. Application of the best-fit equations generally involves quantification of basin characteristics that require or are facilitated by use of a geographic information system. In contrast, the simple equations can be used with information that can be obtained without use of a geographic information system; however, the simple equations have larger prediction errors than the best-fit equations and exhibit geographic biases for most streamflow statistics. The best-fit equations should be used instead of the simple equations whenever possible.

Intra-lymph node injection of biodegradable polymer particles.

PubMed

Andorko, James I; Tostanoski, Lisa H; Solano, Eduardo; Mukhamedova, Maryam; Jewell, Christopher M

2014-01-02

Generation of adaptive immune response relies on efficient drainage or trafficking of antigen to lymph nodes for processing and presentation of these foreign molecules to T and B lymphocytes. Lymph nodes have thus become critical targets for new vaccines and immunotherapies. A recent strategy for targeting these tissues is direct lymph node injection of soluble vaccine components, and clinical trials involving this technique have been promising. Several biomaterial strategies have also been investigated to improve lymph node targeting, for example, tuning particle size for optimal drainage of biomaterial vaccine particles. In this paper we present a new method that combines direct lymph node injection with biodegradable polymer particles that can be laden with antigen, adjuvant, or other vaccine components. In this method polymeric microparticles or nanoparticles are synthesized by a modified double emulsion protocol incorporating lipid stabilizers. Particle properties (e.g. size, cargo loading) are confirmed by laser diffraction and fluorescent microscopy, respectively. Mouse lymph nodes are then identified by peripheral injection of a nontoxic tracer dye that allows visualization of the target injection site and subsequent deposition of polymer particles in lymph nodes. This technique allows direct control over the doses and combinations of biomaterials and vaccine components delivered to lymph nodes and could be harnessed in the development of new biomaterial-based vaccines.

Challenges in recovering resources from acid mine drainage

USGS Publications Warehouse

Nordstrom, D. Kirk; Bowell, Robert J.; Campbell, Kate M.; Alpers, Charles N.

2017-01-01

Metal recovery from mine waters and effluents is not a new approach but one that has occurred largely opportunistically over the last four millennia. Due to the need for low-cost resources and increasingly stringent environmental conditions, mine waters are being considered in a fresh light with a designed, deliberate approach to resource recovery often as part of a larger water treatment evaluation. Mine water chemistry is highly dependent on many factors including geology, ore deposit composition and mineralogy, mining methods, climate, site hydrology, and others. Mine waters are typically Ca-Mg-SO4±Al±Fe with a broad range in pH and metal content. The main issue in recovering components of these waters having potential economic value, such as base metals or rare earth elements, is the separation of these from more reactive metals such as Fe and Al. Broad categories of methods for separating and extracting substances from acidic mine drainage are chemical and biological. Chemical methods include solution, physicochemical, and electrochemical technologies. Advances in membrane techniques such as reverse osmosis have been substantial and the technique is both physical and chemical. Biological methods may be further divided into microbiological and macrobiological, but only the former is considered here as a recovery method, as the latter is typically used as a passive form of water treatment.

Haneş and Valea Vinului (Romania) closed mines Acid Mine Drainages (AMDs)--actual condition and passive treatment remediation proposal.

PubMed

Măicăneanu, Andrada; Bedelean, Horea; Ardelean, Marius; Burcă, Silvia; Stanca, Maria

2013-10-01

Acid Mine Drainages (AMDs) from Haneş and Valea Vinului (Romania) closed mines were considered for characterization and treatment using a local zeolitic volcanic tuff, ZVT, (Măcicaş, Cluj County, Romania). Water samples were collected from two locations, before and after discharging point in case of Haneş mine, and on three horizons in case of Valea Vinului mine. Physico-chemical (pH, total solid, heavy metal ions concentration) analyses showed that the environment is strongly affected by these AMD discharges even if the mines were closed years ago. Iron, manganese and zinc were the main pollutants identified in Haneş mine AMD, while zinc is the one mainly present in case of Valea Vinului AMD. A batch technique (no stirring) in which the ZVT was put in contact with the AMD sample was proposed as a passive remediation technique. ZVT successfully remove heavy metal ion from AMD. According to heavy metal ion concentrations, removal efficiencies are reaching 100%, varying as follows, Fe(2+)>Zn(2+)>Mn(2+). When the ZVT was compared with two cationic resins (strong, SAR and weak acid, WAR) the following series was depicted, SAR>ZVT>WAR. Copyright © 2013 Elsevier Ltd. All rights reserved.

Comparison of techniques for transdiaphragmatic thoracic drainage after diaphragmatic defect closure in dogs: a cadaveric study

PubMed Central

Yoon, Hun-Young; Mann, F. A.; Lee, Suhwon

2013-01-01

Four thoracic evacuation techniques for pneumothorax elimination after diaphragmatic defect closure were compared in 40 canine cadavers. After creating a defect in the left side of the diaphragm, thoracic drainage was performed by thoracostomy tube insertion through the defect and a small (DD-SP) or large (DD-LP) puncture created in the caudal mediastinum, or through both the diaphragmatic defect and intact contralateral diaphragm with a small (DI-SP) or large (DI-LP) puncture in made in the caudal mediastinum. Differences in intrapleural pressure (IPP) between the right and left hemithoraxes after air evacuation along with differences in IPP before making a defect and after air evacuation in each hemithorax were calculated. A difference (p ≤ 0.0011) in IPP between the left and right hemithoraxes after air evacuation as well as before making a defect and after air evacuation in the right hemithorax was detected for the DD-SP group. No significant differences (p ≥ 0.0835) were observed for the DI-LP, DD-LP, or DI-SP groups. Creation of a large mediastinal puncture or thoracic evacuation through both a diaphragmatic defect and intact contralateral diaphragm can facilitate proper pneumothorax elimination bilaterally after diaphragmatic defect closure in dogs with a small puncture in the caudal mediastinum. PMID:23814472

An In Vivo Study of Low-Dose Intra-Articular Tranexamic Acid Application with Prolonged Clamping Drain Method in Total Knee Replacement: Clinical Efficacy and Safety.

PubMed

Sa-ngasoongsong, Paphon; Chanplakorn, Pongsthorn; Wongsak, Siwadol; Uthadorn, Krisorn; Panpikoon, Tanapong; Jittorntam, Paisan; Aryurachai, Katcharin; Angchaisukisiri, Pantap; Kawinwonggowit, Viroj

2015-01-01

Recently, combined intra-articular tranexamic acid (IA-TXA) injection with clamping drain method showed efficacy for blood loss and transfusion reduction in total knee replacement (TKR). However, until now, none of previous studies revealed the effect of this technique on pharmacokinetics, coagulation, and fibrinolysis. An experimental study was conducted, during 2011-2012, in 30 patients undergoing unilateral TKR. Patients received IA-TXA application and then were allocated into six groups regarding clamping drain duration (2-, 4-, 6-, 8-, 10-, and 12-hours). Blood and drainage fluid were collected to measure tranexamic acid (TXA) level and related coagulation and fibrinolytic markers. Postoperative complication was followed for one year. There was no significant difference of serum TXA level at 2 hour and 24 hour among groups (p < 0.05). Serum TXA level at time of clamp release was significantly different among groups with the highest level at 2 hour (p < 0.0001). There was no significant difference of TXA level in drainage fluid, postoperative blood loss, blood transfusion, and postoperative complications (p < 0.05). Low-dose IA-TXA application in TKR with prolonged clamping drain method is a safe and effective blood conservative technique with only minimal systemic absorption and without significant increase in systemic absorption over time.

Effects of the inner droplet of double emulsions on the film drainage during a head-on collision

NASA Astrophysics Data System (ADS)

Wang, Jingtao; Jing, Hefeng; Xu, Genmiao; Wang, Xiaoyong; Duan, Zhenya

2015-07-01

As a critical stage which severely affects the final coalescence of droplets, film drainage in the collision process of two simple droplets has been deeply studied for many years. However, the collision of multiple emulsions which contain other phases (like daughter droplets or particles) has never been studied although multiple emulsions are very important in emulsion industries nowadays. In this paper, the head-on collision of two core-shell double emulsions with equal sizes is investigated through a boundary integral method to disclose the effects of the inner droplet on the film drainage. When capillary number Ca is relatively high, due to the effect of the inner droplet on the inner circulation of mother droplets, the film drainage of double emulsions includes three stages: drainage, drainage halt, and second drainage, instead of two stages for that of simple droplets: drainage and drainage halt.

Are there still roles for exocrine bladder drainage and portal venous drainage for pancreatic allografts?

PubMed

Young, Carlton J

2009-02-01

Controversy remains regarding the best methodology of handling exocrine pancreatic fluid and pancreatic venous effluent. Bladder drainage has given way to enteric drainage. However, is there an instance in which bladder drainage is preferable? Also, hyperinsulinemia, as a result of systemic venous drainage (SVD), is claimed to be proatherosclerotic, whereas portal venous drainage (PVD) is more physiologic and less atherosclerotic. Bladder drainage remains a viable method of exocrine pancreas drainage, but evidence is sparse that measuring urinary amylase has a substantial benefit in the early detection of acute rejection in all types of pancreas transplants. Currently, there is no incontrovertible evidence that systemic hyperinsulinemia is proatherosclerotic, whereas recent metabolic studies on SVD and PVD showed that there was no benefit to PVD. Given the advent of newer immunosuppressive agents and overall lower acute rejection rates, the perceived benefit of bladder drainage as a means to measure urinary amylase as an early marker of rejection has not been substantiated. However, there may be a selective role for bladder drainage in 'high risk' pancreases. Also, without a clear-cut metabolic benefit to PVD over SVD, it remains the surgeon's choice as to which method to use.

Patterns and Rates of Supplementary Venous Drainage to the Internal Jugular Veins.

PubMed

Qureshi, Adnan I; Ishfaq, Muhammad Fawad; Herial, Nabeel A; Khan, Asif A; Suri, M Fareed K

2016-07-01

Several studies have found supplemental venous drainage channels in addition to bilateral internal jugular veins for cerebral venous efflux. We performed this study to characterize the supplemental venous outflow patterns in a consecutive series of patients undergoing detailed cerebral angiography with venous phase imaging. The venographic phase of the arteriogram was reviewed to identify and classify supplemental cerebral venous drainage into anterior (cavernous venous sinus draining into pterygoid plexus and retromandibular vein) and posterior drainage pattern. The posterior drainage pattern was further divided into plexiform pattern (with sigmoid venous sinus draining into the paravertebral venous plexus), and solitary vein pattern (dominant single draining deep cervical vein) drainage. The posterior plexiform pattern was further divided into 2 groups: posterior plexiform with or without prominent solitary vein. Supplemental venous drainage was seen ipsilateral to internal jugular vein in 76 (43.7%) of 174 venous drainages (87 patients) analyzed. The patterns were anterior (n = 23, 13.2%), posterior plexiform without prominent solitary vein (n = 40, 23%), posterior plexiform with prominent solitary vein (n = 62, 35.6%), and posterior solitary vein alone (n = 3, 1.7%); occipital emissary veins and/or transosseous veins were seen in 1 supplemental venous drainage. Concurrent ipsilateral anterior and posterior supplemental drainage was seen in 6 of 174 venous drainages analyzed. We provide an assessment of patterns and rates of supplementary venous drainage to internal jugular veins to improve our understanding of anatomical and physiological aspects of cerebral venous drainage. Copyright © 2016 by the American Society of Neuroimaging.

Standard (head-down tilt) versus modified (without head-down tilt) postural drainage in infants and young children with cystic fibrosis.

PubMed

Freitas, Diana A; Chaves, Gabriela Ss; Santino, Thayla A; Ribeiro, Cibele Td; Dias, Fernando Al; Guerra, Ricardo O; Mendonça, Karla Mpp

2018-03-09

Postural drainage is used primarily in infants with cystic fibrosis from diagnosis up to the moment when they are mature enough to actively participate in self-administered treatments. However, there is a risk of gastroesophageal reflux associated with this technique.This is an update of a review published in 2015. To compare the effects of standard postural drainage (15º to 45º head-down tilt) with modified postural drainage (15º to 30º head-up tilt) with regard to gastroesophageal reflux in infants and young children up to six years old with cystic fibrosis in terms of safety and efficacy. We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group's Cystic Fibrosis Trials Register. We also searched the reference lists of relevant articles and reviews. Additional searches were conducted on ClinicalTrials.gov and on the WHO International Clinical Trials Registry Platform for any planned, ongoing and unpublished studies.The date of the most recent literature searches: 19 June 2017. We included randomised controlled studies that compared two postural drainage regimens (standard and modified postural drainage) with regard to gastroesophageal reflux in infants and young children (up to and including six years old) with cystic fibrosis. We used standard methodological procedures expected by Cochrane. Two review authors independently identified studies for inclusion, extracted outcome data and assessed risk of bias. We resolved disagreements by consensus or by involving a third review author. We contacted study authors to obtain missing or additional information. The quality of the evidence was assessed using GRADE. Two studies, involving a total of 40 participants, were eligible for inclusion in the review. We included no new studies in the 2018 update. The included studies were different in terms of the age of participants, the angle of tilt, the reported outcomes, the number of sessions and the study duration. The following outcomes were measured: appearance or exacerbation of gastroesophageal reflux episodes; percentage of peripheral oxygen saturation; number of exacerbations of upper respiratory tract symptoms; number of days on antibiotics for acute exacerbations; chest X-ray scores; and pulmonary function tests. One study reported that postural drainage with a 20° head-down position did not appear to exacerbate gastroesophageal reflux. However, the majority of the reflux episodes in this study reached the upper oesophagus (moderate-quality evidence). The second included study reported that modified postural drainage (30° head-up tilt) was associated with fewer number of gastroesophageal reflux episodes and fewer respiratory complications than standard postural drainage (30° head-down tilt) (moderate-quality evidence). The included studies had an overall low risk of bias. One included study was funded by the Sydney Children's Hospital Foundation and the other by the Royal Children's Hospital Research Foundation and Physiotherapy Research Foundation of Australia. Data were not able to be pooled by meta-analysis due to differences in the statistical presentation of the data. The limited evidence regarding the comparison between the two regimens of postural drainage is still weak due to the small number of included studies, the small number of participants assessed, the inability to perform any meta-analyses and some methodological issues with the studies. However, it may be inferred that the use of a postural regimen with a 30° head-up tilt is associated with a lower number of gastroesophageal reflux episodes and fewer respiratory complications in the long term. The 20° head-down postural drainage position was not found to be significantly different from the 20° head-up tilt modified position. Nevertheless, the fact that the majority of reflux episodes reached the upper oesophagus should make physiotherapists carefully consider their treatment strategy. We do not envisage that there will be any new trials undertaken that will affect the conclusions of this review; therefore, we do not plan to update this review.

Subsurface drainage volume reduction with drainage water management: Case studies in Ohio, USA

USDA-ARS?s Scientific Manuscript database

One of the main contributors to poor water quality in the Mississippi River and aeral increase in the hypoxic zone in the Gulf of Mexico is intensive drainage of the cropland within the watershed. Controlled drainage has been demonstrated as an approach to curb totla drainage outflow and nutrient di...

Lower extremity manifestations of "skin-popping" an illicit drug use technique: A report of two cases.

PubMed

Canales, Michael; Gerhard, John; Younce, Erin

2015-06-01

Presented is a rare case of tibial and fibular osteomyelitis and a case of fibular periositis, both a direct consequence of a peculiar drug use technique. The osseous manifestations secondary to presentation of necrotic wounds with indurated rim and serous drainage with associated cellulitis, both resulting from "skin popping." Due to the complex treatment plan required, the importance of a motivated patient, a strong social support system, a controlled environment, and a multidisciplinary team cannot be overstated. Despite comprehensive efforts, devastating consequences may be unavoidable as individuals plunge downward, victimized by their addiction. 4. Copyright © 2015 Elsevier Ltd. All rights reserved.

Capillary pressure curves for low permeability chalk obtained by NMR imaging of core saturation profiles

DOE Office of Scientific and Technical Information (OSTI.GOV)

Norgaard, J.V.; Olsen, D.; Springer, N.

1995-12-31

A new technique for obtaining water-oil capillary pressure curves, based on NMR imaging of the saturation distribution in flooded cores is presented. In this technique, a steady state fluid saturation profile is developed by flooding the core at a constant flow rate. At the steady state situation where the saturation distribution no longer changes, the local pressure difference between the wetting and non-wetting phases represents the capillary pressure. The saturation profile is measured using an NMR technique and for a drainage case, the pressure in the non-wetting phase is calculated numerically. The paper presents the NMR technique and the proceduremore » for calculating the pressure distribution in the sample. Inhomogeneous samples produce irregular saturation profiles, which may be interpreted in terms of variation in permeability, porosity, and capillary pressure. Capillary pressure curves for North Sea chalk obtained by the new technique show good agreement with capillary pressure curves obtained by traditional techniques.« less

Slit-lamp technique of draining interface fluid following Descemet's stripping endothelial keratoplasty.

PubMed

Srinivasan, Sathish; Rootman, David S

2007-09-01

To describe a new slit-lamp technique for draining interface fluid to manage complete donor disc detachments following Descemet's stripping (automated) endothelial keratoplasty (DSEK/DSAEK). Interventional case series. Five DSEK/DSAEK patients presented on the first postoperative day with complete detachment of the donor lenticule. Slit-lamp biomicroscopy showed interface fluid preventing attachment of the donor disc to the host stromal bed. A new slit-lamp technique is described to drain the interface fluid. This technique involved completely filling the anterior chamber with an air bubble using a 30-gauge needle on a 3 ml syringe. Following this, a 0.12 forceps was used to open the inferior mid-peripheral corneal drainage slit to drain the interface fluid. This technique was successful in draining the interface fluid in all five patients, leading to immediate complete reattachment of the donor disc. Donor disc detachments following DSEK/DSAEK can be successfully managed by this slit-lamp technique of draining the interface fluid.

After-discovery studies prolong life. [Role of the geologist in oil fields

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hartman, J.A.

1977-05-02

Unless there is a problem, a field may receive little attention by geologists once the primary development phase is over. This is a mistake because analysis of production data may point to areas where more development is needed. In large, multipay fields it is hard to gather the data into a usable form and to attempt to use these data to develop a consistent subsurface interpretation which explains the facts. With wells spaced only a few hundred feet apart, the geologist cannot let his imagination run wild as he can when looking at wildcat country. However, the results obtained frommore » studying oil fields can be very rewarding for both the geologist and his company. For maximum benefit, a subsurface field review should include all facts of the geology, as well as the reservoir, petro-physical, and production engineering aspects. When a field is studied in detail, areas of poor drainage are generally found and those become potential objectives for new wells on recompletions in existing wells. The following are discussed: (1) updip undrained areas; (2) bottom water reservoirs; (3) stringer drainage; and (4) South Pass block 24 field. When a field is studied in detail, unanticipated drainage anomalies are commonly found.« less

A Meta-Analysis of the Effect of Preoperative Biliary Stenting on Patients With Obstructive Jaundice

PubMed Central

Sun, Chengyi; Yan, Guirong; Li, Zhiming; Tzeng, Chi-Meng

2014-01-01

Abstract The goal of this study was to systematically review the effects of biliary stenting on postoperative morbidity and mortality of patients with obstructive jaundice. PubMed, Embase, Cochrane Library, and other relevant databases were searched by computer and manually for published and unpublished studies on the impact of preoperative biliary drainage on patients with obstructive jaundice from 2000 to the present day. Two investigators independently selected the studies according to the inclusion and exclusion criteria, extracted the data, and assessed the quality of the selected studies. Meta-analysis was performed to compare postoperative morbidity and mortality of patients between the drainage and nondrainage groups. Compared with the nondrainage group, the overall mortality, overall morbidity, infectious morbidity, incidence of wound infection, intra-abdominal abscess, pancreatic fistulas, bile leak, and delayed gastric emptying in the drainage group were not significantly different. Compared with the nondrainage group, the drainage group had a drainage time of <4 weeks with an increased overall morbidity by 7% to 23%; however, the overall morbidity of the drainage group with a drainage time >4 weeks was not significantly different. Compared with the nondrainage group, the overall mortality of the drainage group using metal stents and plastic stents as internal drainage devices was reduced by 0.5% to 6%, whereas that of the drainage group using plastic stent devices was not significantly different. In summary, preoperative drainage should be applied selectively. The drainage time should be >4 weeks, and metal stents should be used for internal drainage. PMID:25474436

[The impact of preoperative biliary drainage on surgical morbidity in hilar cholangiocarcinoma patients].

PubMed

Li, Shao-qiang; Chen, Dong; Liang, Li-jian; Peng, Bao-gang; Yin, Xiao-yu

2009-08-01

To evaluate the impact of preoperative biliary drainage on surgical morbidity in hilar cholangiocarcinoma patients underwent surgery. One hundred and eleven consecutive patients with hilar cholangiocarcinoma whose serum total bilirubin (TBIL) level > 85 micromol/L and underwent surgery in the period from June 1998 to August 2007 were enrolled. There were 67 male and 44 female patients, aged from 26 to 82 years old with a mean of 56 years old. Fifty-five patients underwent preoperative biliary drainage with a mean of 11.4 d of drainage period (drainage group), the other (n = 56) were the non-drainage group. The preoperative TBIL level of drainage group was (154 +/- 69) micromol/L, which was significantly lower than the value of pre-drainage (256 +/- 136) micromol/L (P = 0.000) and the value of non-drainage group (268 +/- 174) micromol/L (P = 0.005). ALT and GGT levels could be lowered by preoperative biliary drainage. The postoperative complications of these two groups were comparable (36.3% vs. 28.6%, P = 0.381). Four patients in drainage group and 5 patients in non-drainage group died of liver failure. Multivariate logistic regression indicated that hepatectomy (OR = 0.284, P = 0.003) was the independent risk factor associated with postoperative morbidity. Bismuth-Corlette classification (OR = 0.211, P = 0.028) was the independent risk factor linked to postoperative mortality. Preoperative biliary drainage could alleviate liver injury due to hyperbilirubin, but it could not decrease the surgical morbidity and postoperative mortality. Concomitant hepatectomy and Bismuth-Corlette classification were independent risk factors linked to surgical risks.

The strategies of local farmers' water management and the eco-hydrological effects of irrigation-drainage engineering systems in world heritage of Honghe Hani Rice Terraces

NASA Astrophysics Data System (ADS)

Gao, Xuan

2017-04-01

Terraces are built in mountainous regions to provide larger area for cultivation,in which the hydrological and geomorphological processes are impacted by local farmers' water management strategies and are modified by manmade irrigation-drainage engineering systems.The Honghe Hani Rice Terraces is a 1300a history of traditional agricultural landscape that was inscribed in the 2013 World Heritage List.The local farmers had developed systematic water management strategies and built perfect irrigation-drainage engineering systems to adapt the local rainfall pattern and rice farming activities.Through field investigation,interviews,combined with Geographic Information Systems,Remote Sensing images and Global Positioning Systems technology,the water management strategies as well as the irrigation-drainage systems and their impacts on eco-hydrological process were studied,the results indicate:Firstly,the local people created and maintained an unique woodcarving allocating management system of irrigating water over hundreds years,which aids distributing water and natural nutrition to each terrace field evenly,and regularly according to cultivation schedule.Secondly,the management of local people play an essential role in effective irrigation-drainage engineering system.A ditch leader takes charge of managing the ditch of their village,keeping ample amount of irrigation water,repairing broken parts of ditches,dealing with unfair water using issues,and so on.Meanwhile,some traditional leaders of minority also take part in.Thus, this traditional way of irrigation-drainage engineering has bringed Hani people around 1300 years of rice harvest for its eco-hydrological effects.Lastly we discuss the future of Honghe Hani Rice Terraces,the traditional cultivation pattern has been influenced by the rapid development of modern civilization,in which some related changes such as the new equipment of county roads and plastic channels and the water overusing by tourism are not totally rely on eco-hydrological engineering rules,which broke the ecosystem stability of agricultural terraces.The current situation of Honghe Hani Rice Terraces heritage cannot completely meets the purpose of sustainability development and appropriate conservation of Honghe Hani Rice Terraces heritage.This study of traditional cultivation pattern can help us to propose rational solutions for future development of terraces heritages. Key words:Honghe Hani Rice Terraces,water management,eco-hydrological effects,heritage conservation

Drainage capture and discharge variations driven by glaciation in the Southern Alps, New Zealand

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ann V. Rowan; Mitchell A. Plummer; Simon H. Brocklehurst

Sediment flux in proglacial fluvial settings is primarily controlled by discharge, which usually varies predictably over a glacial–interglacial cycle. However, glaciers can flow against the topographic gradient to cross drainage divides, reshaping fluvial drainage networks and dramatically altering discharge. In turn, these variations in discharge will be recorded by proglacial stratigraphy. Glacial-drainage capture often occurs in alpine environments where ice caps straddle range divides, and more subtly where shallow drainage divides cross valley floors. We investigate discharge variations resulting from glacial-drainage capture over the past 40 k.y. for the adjacent Ashburton, Rangitata, and Rakaia basins in the Southern Alps, Newmore » Zealand. Although glacial-drainage capture has previously been inferred in the range, our numerical glacier model provides the first quantitative demonstration that this process drives larger variations in discharge for a longer duration than those that occur due to climate change alone. During the Last Glacial Maximum, the effective drainage area of the Ashburton catchment increased to 160% of the interglacial value with drainage capture, driving an increase in discharge exceeding that resulting from glacier recession. Glacial-drainage capture is distinct from traditional (base level–driven) drainage capture and is often unrecognized in proglacial deposits, complicating interpretation of the sedimentary record of climate change.« less

Assessment of the service performance of drainage system and transformation of pipeline network based on urban combined sewer system model.

PubMed

Peng, Hai-Qin; Liu, Yan; Wang, Hong-Wu; Ma, Lu-Ming

2015-10-01

In recent years, due to global climate change and rapid urbanization, extreme weather events occur to the city at an increasing frequency. Waterlogging is common because of heavy rains. In this case, the urban drainage system can no longer meet the original design requirements, resulting in traffic jams and even paralysis and post a threat to urban safety. Therefore, it provides a necessary foundation for urban drainage planning and design to accurately assess the capacity of the drainage system and correctly simulate the transport effect of drainage network and the carrying capacity of drainage facilities. This study adopts InfoWorks Integrated Catchment Management (ICM) to present the two combined sewer drainage systems in Yangpu District, Shanghai (China). The model can assist the design of the drainage system. Model calibration is performed based on the historical rainfall events. The calibrated model is used for the assessment of the outlet drainage and pipe loads for the storm scenario currently existing or possibly occurring in the future. The study found that the simulation and analysis results of the drainage system model were reliable. They could fully reflect the service performance of the drainage system in the study area and provide decision-making support for regional flood control and transformation of pipeline network.

Pseudocyst in the pancreatic tail associated with chronic pancreatitis successfully treated by transpapillary cyst drainage.

PubMed

Naitoh, Itaru; Ohara, Hirotaka; Okayama, Yasutaka; Nakazawa, Takahiro; Ando, Tomoaki; Hayashi, Kazuki; Okumura, Fumihiro; Kitajima, Yasuhiro; Ban, Tessin; Miyabe, Katsuyuki; Ueno, Koichiro; Joh, Takashi; Sano, Hitoshi

2008-09-01

We report a 50-year-old male with pseudocysts in the pancreatic tail associated with chronic pancreatitis successfully treated by transpapillary cyst drainage. He had previously undergone ultrasonography-guided percutaneous cyst drainage for a pancreatic pseudocyst in our hospital. He was readmitted due to abdominal pain and fever. Computed tomography showed recurrence of a pseudocyst in the pancreatic tail measuring 5 cm in diameter. Since conservative treatment failed, endoscopic retrograde pancreatography was performed. There was communication between the pseudocyst and the main pancreatic duct, and pancreatic duct stenosis proximal to the pseudocyst. First, transpapillary pancreatic duct drainage was performed using a plastic stent, but the pseudocyst did not decrease in size and became infected. After removal of the stent, a pigtail type nasocystic catheter was placed in the pseudocyst via the pancreatic duct. The pseudocyst infection immediately disappeared, and the pseudocyst gradually decreased and disappeared. After removal of the nasocystic catheter, no recurrence was observed. As transpapillary drainage of pancreatic pseudocyst, cyst drainage and pancreatic duct drainage have been reported. In our patient with pseudocyst in the pancreatic tail, duct drainage was ineffective and the pseudocyst was infected, whereas cyst drainage was very effective. We considered that cyst drainage by a nasocystic catheter was the first-line therapy as the transpapillary drainage of the pancreatic pseudocyst.

Inventory of drainage wells and potential sources of contaminants to drainage-well inflow in Southwest Orlando, Orange County, Florida

USGS Publications Warehouse

Taylor, George Fred

1993-01-01

Potential sources of contaminants that could pose a threat to drainage-well inflow and to water in the Floridan aquifer system in southwest Orlando, Florida, were studied between October and December 1990. Drainage wells and public-supply wells were inventoried in a 14-square-mile area, and available data on land use and activities within each drainage well basin were tabulated. Three public-supply wells (tapping the Lower Floridan aquifer) and 38 drainage wells (open to the Upper Floridan aquifer) were located in 17 drainage basins within the study area. The primary sources of drainage-well inflow are lake overflow, street runoff, seepage from the surficial aquifer system, and process-wastewater disposal. Drainage-well inflow from a variety of ares, including resi- dential, commercial, undeveloped, paved, and industrial areas, are potential sources of con- taminants. The four general types of possible contaminants to drainage-well inflow are inorganic chemicals, organic compounds, turbidity, and microbiological contaminants. Potential contami- nant sources include plant nurseries, citrus groves, parking lots, plating companies, auto- motive repair shops, and most commonly, lake- overflow water. Drainage wells provide a pathway for contaminants to enter the Upper Floridan aquifer and there is a potential for contaminants to move downward from the Upper Floridan to the Lower Floridan aquifer.

[Application research of presacral space drainage tube combined with subcutaneous vacuum pressure suction in the laparoscopic-assisted abdominoperineal resection].

PubMed

Chen, Liqi; Zeng, Changqing; Chi, Liangjie; Huang, Liangxiang; Li, Jiandang

2017-08-25

To study the management for the perineal incision after laparoscopic-assisted abdominoperineal resection for rectal cancer. Clinical data of 87 patients undergoing laparoscopic Miles operation for lower rectal cancer from June 2009 to February 2014 were collected and studied. Presacral space drainage group: presacral space drainage tube was applied in 42 patients. Combined drainage group: presacral space drainage tube combined with subcutaneous vacuum pressure suction was applied in 45 cases. In combined drainage group, except the presacral drainage tube, another drainage tube was placed subcutaneously and connected to a negative pressure ball, which was fixed on the lateral anterior of perineal wound by the further incision and drainage. After subcutaneous tube was placed for 2 weeks, as drainage fluid was limpid and <15 ml/d for 3 days, meanwhile no obvious pelvic fluid was detected by ultrasound, and the wound healed quite well without redness and edema, then the subcutaneous tube with the negative pressure ball could be removed. There were 51 males and 36 females with the mean age of 26-78(56.9±10.8) years old. The laparoscopic Miles operation was successfully completed in all the cases without death and complications. The drainage tube was placed for 4-13(8.0±2.5) days in presacral space drainage group, and for 4-14(6.7±2.4) days in combined drainage group. The subcutaneous tube was placed for 14-24(15.8±3.0) days. The primary healing rate of perineal wound in presacral space drainage group and combined drainage group was 66.7%(28/42) and 91.1%(41/45) respectively, while the perineal wound infection rate was 21.4%(9/42) and 4.4%(2/45) respectively, whose differences between two groups were both significant (χ 2 =7.911, P=0.005 and χ 2 =5.674, P=0.017). Presacral space drainage tube combined with subcutaneous vacuum pressure suction in laparoscopic-assisted abdominoperineal resection for rectal cancer has better efficacy and lower infection rate for perineal incision, which is worth wide application.

Management of Pleural Effusion, Empyema, and Lung Abscess

PubMed Central

Yu, Hyeon

2011-01-01

Pleural effusion is an accumulation of fluid in the pleural space that is classified as transudate or exudate according to its composition and underlying pathophysiology. Empyema is defined by purulent fluid collection in the pleural space, which is most commonly caused by pneumonia. A lung abscess, on the other hand, is a parenchymal necrosis with confined cavitation that results from a pulmonary infection. Pleural effusion, empyema, and lung abscess are commonly encountered clinical problems that increase mortality. These conditions have traditionally been managed by antibiotics or surgical placement of a large drainage tube. However, as the efficacy of minimally invasive interventional procedures has been well established, image-guided small percutaneous drainage tubes have been considered as the mainstay of treatment for patients with pleural fluid collections or a lung abscess. In this article, the technical aspects of image-guided interventions, indications, expected benefits, and complications are discussed and the published literature is reviewed. PMID:22379278

A new species of Pareiorhaphis (Siluriformes: Loricariidae) from the headwaters of the Arroio Garapiá, coastal drainage of Rio Grande do Sul state, Brazil.

PubMed

Pereira, Edson H L; Lehmann, Pablo A; Schvambach, Lucas J; Reis, Roberto E

2015-10-30

Pareiorhaphis garapia, new species, is described based on specimens collected in the headwaters of the Arroio Garapiá, Rio Maquiné basin, a coastal drainage of Rio Grande do Sul State, southern Brazil. The new species is distinguished from all other Pareiorhaphis species in having the nuchal plate covered by thick skin, the exposed posterior process of the cleithrum comparatively narrow, and the last segment of the preopercular ramus of the latero-sensory canal reduced to an ossified tubule. The absence of a dorsal-fin spinelet, the reduced number of plates in the dorsal and mid-dorsal series of lateral plates, and morphometric traits also distinguish the new species from its congeners. The restricted geographic distribution of P. garapia, endemic to a headwater stream of the Rio Maquiné basin, and the syntopic occurrence of P. nudulus are discussed.

Surfactant effect on drop coalescence and film drainage hydrodynamics

NASA Astrophysics Data System (ADS)

Weheliye, Weheliye; Chinaud, Maxime; Voulgaropoulos, Victor; Angeli, Panagiota

2015-11-01

Coalescence of a drop on an aqueous-organic interface is studied in two test geometries A rectangular acrylic vessel and a Hele-Shaw cell (two parallel plates placed 2mm apart) are investigated for the experiments. Time resolved Particle Image Velocimetry (PIV) measurements provide information on the hydrodynamics during the bouncing stage of the droplet and on the vortices generated at the bulk fluid after the droplet has coalesced. The velocity field inside the droplet during its coalescence is presented. By localizing the rupture point of the coalescence in the quasi two dimensional cell, the film drainage dynamics are discussed by acquiring its flow velocity by PIV measurements with a straddling camera. The effect of surface tension forces in the coalescence of the droplet is investigated by introducing surface active agents at various concentrations extending on both sides of the critical micelle concentration.

Hydrology of area 51, northern Great Plains and Rocky Mountain coal provinces, Wyoming and Montana

USGS Publications Warehouse

Peterson, David A.; Mora, K.L.; Lowry, Marlin E.; Rankl, James G.; Wilson, James F.; Lowham, H.W.; Ringen, Bruce H.

1987-01-01

This report is one of a series designed to characterize the hydrology of drainage basins within coal provinces, nationwide. Area 51 (in the Rocky Mountain Coal Province) includes all or part of the Shoshone, Bighorn, Greybull, Wind, and Popo Agie River drainage basins - a total of 11,800 sq mi. Area 51 contains more than 18 million tons of strippable bituminous coal and extensive deposits of subbituminous coal, in the arid and semiarid basins. The report represents a summary of results of water resources investigations of the U.S. Geological Survey, some of which were conducted in cooperation with State and other Federal agencies. More than 30 individual topics are discussed in brief texts that are accompanied by maps, graphs, photographs , and illustrations. Primary topics in the reports are physiography, resources and economy, surface-water quantity and quality, and groundwater. (USGS)

Decision strategies for handling the uncertainty of future extreme rainfall under the influence of climate change.

PubMed

Gregersen, I B; Arnbjerg-Nielsen, K

2012-01-01

Several extraordinary rainfall events have occurred in Denmark within the last few years. For each event, problems in urban areas occurred as the capacity of the existing drainage systems were exceeded. Adaptation to climate change is necessary but also very challenging as urban drainage systems are characterized by long technical lifetimes and high, unrecoverable construction costs. One of the most important barriers for the initiation and implementation of the adaptation strategies is therefore the uncertainty when predicting the magnitude of the extreme rainfall in the future. This challenge is explored through the application and discussion of three different theoretical decision support strategies: the precautionary principle, the minimax strategy and Bayesian decision support. The reviewed decision support strategies all proved valuable for addressing the identified uncertainties, at best applied together as they all yield information that improved decision making and thus enabled more robust decisions.

Effect of abdominopelvic abscess drain size on drainage time and probability of occlusion

PubMed Central

Rotman, Jessica A.; Getrajdman, George I.; Maybody, Majid; Erinjeri, Joseph P.; Yarmohammadi, Hooman; Sofocleous, Constantinos T.; Solomon, Stephen B.; Boas, F. Edward

2016-01-01

Background The purpose of this study is to determine whether larger abdominopelvic abscess drains reduce the time required for abscess resolution, or the probability of tube occlusion. Methods 144 consecutive patients who underwent abscess drainage at a single institution were reviewed retrospectively. Results: Larger initial drain size did not reduce drainage time, drain occlusion, or drain exchanges (p>0.05). Subgroup analysis did not find any type of collection that benefitted from larger drains. A multivariate model predicting drainage time showed that large collections (>200 ml) required 16 days longer drainage time than small collections (<50 ml). Collections with a fistula to bowel required 17 days longer drainage time than collections without a fistula. Initial drain size and the viscosity of the fluid in the collection had no significant effect on drainage time in the multivariate model. Conclusions 8 F drains are adequate for initial drainage of most serous and serosanguineous collections. 10 F drains are adequate for initial drainage of most purulent or bloody collections. PMID:27634422

The Utility and Benefits of External Lumbar CSF Drainage after Endovascular Coiling on Aneurysmal Subarachnoid Hemorrhage

PubMed Central

Kwon, Ou Young; Kim, Young Jin; Cho, Chun Sung; Lee, Sang Koo; Cho, Maeng Ki

2008-01-01

Objective Cerebral vasospasm still remains a major cause of the morbidity and mortality, despite the developments in treatment of aneurysmal subarachnoid hemorrhage. The authors measured the utility and benefits of external lumbar cerebrospinal fluid (CSF) drainage to prevent the clinical vasospasm and its sequelae after endovascular coiling on aneurysmal subarachnoid hemorrhage in this randomized study. Methods Between January 2004 and March 2006, 280 patients with aneurysmal subarachnoid hemorrhage were treated at our institution. Among them, 107 patients met our study criteria. The treatment group consisted of 47 patients who underwent lumbar CSF drainage during vasospasm risk period (about for 14 days after SAH), whereas the control group consisted of 60 patients who received the management according to conventional protocol without lumbar CSF drainage. We created our new modified Fisher grade on the basis of initial brain computed tomography (CT) scan at admission. The authors established five outcome criteria as follows : 1) clinical vasospasm; 2) GOS score at 1-month to 6-month follow-up; 3) shunt procedures for hydrocephalus; 4) the duration of stay in the ICU and total hospital stay; 5) mortality rate. Results The incidence of clinical vasospasm in the lumbar drain group showed 23.4% compared with 63.3% of individuals in the control group. Moreover, the risk of death in the lumbar drain group showed 2.1% compared with 15% of individuals in the control group. Within individual modified Fisher grade, there were similar favorable results. Also, lumbar drain group had twice more patients than the control group in good GOS score of 5. However, there were no statistical significances in mean hospital stay and shunt procedures between the two groups. IVH was an important factor for delayed hydrocephalus regardless of lumbar drain. Conclusion Lumbar CSF drainage remains to play a prominent role to prevent clinical vasospasm and its sequelae after endovascular coiling on aneurysmal subarachnoid hemorrhage. Also, this technique shows favorable effects on numerous neurological outcomes and prognosis. The results of this study warrant clinical trials after endovascular treatment in patients with aneurysmal SAH. PMID:19096633

Fluvial archives, a valuable record of vertical crustal deformation

NASA Astrophysics Data System (ADS)

Demoulin, A.; Mather, A.; Whittaker, A.

2017-06-01

The study of drainage network response to uplift is important not only for understanding river system dynamics and associated channel properties and fluvial landforms, but also for identifying the nature of crustal deformation and its history. In recent decades, geomorphic analysis of rivers has proved powerful in elucidating the tectonic evolution of actively uplifting and eroding orogens. Here, we review the main recent developments that have improved and expanded qualitative and quantitative information about vertical tectonic motions (the effects of horizontal deformation are not addressed). Channel long profiles have received considerable attention in the literature, and we briefly introduce basic aspects of the behaviour of bedrock rivers from field and numerical modelling perspectives, before describing the various metrics that have been proposed to identify the information on crustal deformation contained within their steady-state characteristics. Then, we review the literature dealing with the transient response of rivers to tectonic perturbation, through the production of knickpoints propagating through the drainage network. Inverse modelling of river profiles for uplift in time and space is also shown to be very effective in reconstructing regional tectonic histories. Finally, we present a synthetic morphometric approach for deducing the tectonic record of fluvial landscapes. As well as the erosional imprint of tectonic forcing, sedimentary deposits, such as fluvial terrace staircases, are also considered as a classical component of tectonic geomorphology. We show that these studies have recently benefited from rapid advances in dating techniques, allowing more reliable reconstruction of incision histories and estimation of incision rates. The combination of progress in the understanding of transient river profiles and larger, more rigorous data sets of terrace ages has led to improved understanding of river erosion and the implications for terrace profile correlation, i.e., extrapolation of local data to entire profiles. Finally, planform changes in fluvial systems are considered at the channel scale in alluvial rivers and regional level in terms of drainage reorganisation. Examples are given of how numerical modelling can efficiently combine with topographic data to shed new light on the (dis)equilibrium state of drainage systems across regional drainage divides.

Distributed and localized horizontal tectonic deformation as inferred from drainage network geometry and topology: A case study from Lebanon

NASA Astrophysics Data System (ADS)

Goren, Liran; Castelltort, Sébastien; Klinger, Yann

2016-04-01

Partitioning of horizontal deformation between localized and distributed modes in regions of oblique tectonic convergence is, in many cases, hard to quantify. As a case study, we consider the Dead Sea Fault System that changes its orientation across Lebanon and forms a restraining bend. The oblique deformation along the Lebanese restraining bend is characterized by a complex suite of tectonic structures, among which, the Yammouneh fault, is believed to be the main strand that relays deformation from the southern section to the northern section of the Dead Sea Fault System. However, uncertainties regarding slip rates along the Yammouneh fault and strain partitioning in Lebanon still prevail. In the current work we use the geometry and topology of river basins together with numerical modeling to evaluate modes and rates of the horizontal deformation in Mount Lebanon that is associated with the Arabia-Sinai relative plate motion. We focus on river basins that drain Mount Lebanon to the Mediterranean and originate close to the Yammouneh fault. We quantify a systematic counterclockwise rotation of these basins and evaluate drainage area disequilibrium using an application of the χ mapping technique, which aims at estimating the degree of geometrical and topological disequilibrium in river networks. The analysis indicates a systematic spatial pattern whereby tributaries of the rotated basins appear to experience drainage area loss or gain with respect to channel length. A kinematic model that is informed by river basin geometry reveals that since the late Miocene, about a quarter of the relative plate motion parallel to the plate boundary has been distributed along a wide band of deformation to the west of the Yammouneh fault. Taken together with previous, shorter-term estimates, the model indicates little variation of slip rate along the Yammouneh fault since the late Miocene. Kinematic model results are compatible with late Miocene paleomagnetic rotations in western Mount Lebanon. A numerical landscape evolution experiment demonstrates the emergence of a similar χ pattern of drainage area disequilibrium in response to progressive distributed shear deformation of river basins with relatively minor drainage network reorganization.

Drainage and impregnation capillary pressure curves calculated by the X-ray CT model of Berea sandstone using Lattice Boltzmann's method

NASA Astrophysics Data System (ADS)

Zakirov, T.; Galeev, A.; Khramchenkov, M.

2018-05-01

The study deals with the features of the technique for simulating the capillary pressure curves of porous media on their X-ray microtomographic images. The results of a computational experiment on the immiscible displacement of an incompressible fluid by another in the pore space represented by a digital image of the Berea sandstone are presented. For the mathematical description of two-phase fluid flow we use Lattice Boltzmann Equation (LBM), and phenomena at the fluids interface are described by the color-gradient model. Compared with laboratory studies, the evaluation of capillary pressure based on the results of a computational filtration experiment is a non-destructive method and has a number of advantages: the absence of labor for preparation of fluids and core; the possibility of modeling on the scale of very small core fragments (several mm), which is difficult to realize under experimental conditions; three-dimensional visualization of the dynamics of filling the pore space with a displacing fluid during drainage and impregnation; the possibility of carrying out multivariate calculations for specified parameters of multiphase flow (density and viscosity of fluids, surface tension, wetting contact angle). A satisfactory agreement of the capillary pressure curves during drainage with experimental results was obtained. It is revealed that with the increase in the volume of the digital image, the relative deviation of the calculated and laboratory data decreases and for cubic digital cores larger than 1 mm it does not exceed 5%. The behavior of the non-wetting fluid flow during drainage is illustrated. It is shown that flow regimes under which computational and laboratory experiments are performed the distribution of the injected phase in directions different from the gradient of the hydrodynamic drop, including the opposite ones, is characteristic. Experimentally confirmed regularities are obtained when carrying out calculations for drainage and imbibition at different values of interfacial tension. There is a close coincidence in the average diameters of permeable channels, estimated by capillary curves for different interfacial tension and pore network model. The differences do not exceed 15%.

Characterizing fish community diversity across Virginia landscapes: Prerequisite for conservation

USGS Publications Warehouse

Angermeier, P.L.; Winston, M.R.

1999-01-01

The number of community types occurring within landscapes is an important, but often unprotected, component of biological diversity. Generally applicable protocols for characterizing community diversity need to be developed to facilitate conservation. We used several multivariate techniques to analyze geographic variation in the composition of fish communities in Virginia streams. We examined relationships between community composition and six landscape variables: drainage basin, physiography, stream order, elevation, channel slope, and map coordinates. We compared patterns at two scales (statewide and subdrainage-specific) to assess sensitivity of community classification to spatial scale. We also compared patterns based on characterizing communities by species composition vs. ecological composition. All landscape variables explained significant proportions of the variance in community composition. Statewide, they explained 32% of the variance in species composition and 48% of the variance in ecological composition. Typical communities in each drainage or physiography were statistically distinctive. Communities in different combinations of drainage, physiography, and stream size were even more distinctive, but composition was strongly spatially autocorrelated. Ecological similarity and species similarity of community pairs were strongly related, but replacement by ecologically similar species was common among drainage-physiography combinations. Landscape variables explained significant proportions of variance in community composition within selected subdrainages, but proportions were less than at the statewide scale, and the explanatory power of individual variables varied considerably among subdrainages. Community variation within subdrainages appeared to be much more closely related to environmental variation than to replacement among ecologically similar species. Our results suggest that taxonomic and ecological characterizations of community composition are complementary; both are useful in a conservation context. Landscape features such as drainage, physiography, and water body size generally may provide a basis for assessing aquatic community diversity, especially in regions where the biota is poorly known. Systematic conservation of community types would be a major advance relative to most current conservation programs, which typically focus narrowly on populations of imperiled species. More effective conservation of aquatic biodiversity will require new approaches that recognize the value of both species and assemblages, and that emphasize protection of key landscape-scale processes.

Modeling of subglacial hydrological development following rapid supraglacial lake drainage.

PubMed

Dow, C F; Kulessa, B; Rutt, I C; Tsai, V C; Pimentel, S; Doyle, S H; van As, D; Lindbäck, K; Pettersson, R; Jones, G A; Hubbard, A

2015-06-01

The rapid drainage of supraglacial lakes injects substantial volumes of water to the bed of the Greenland ice sheet over short timescales. The effect of these water pulses on the development of basal hydrological systems is largely unknown. To address this, we develop a lake drainage model incorporating both (1) a subglacial radial flux element driven by elastic hydraulic jacking and (2) downstream drainage through a linked channelized and distributed system. Here we present the model and examine whether substantial, efficient subglacial channels can form during or following lake drainage events and their effect on the water pressure in the surrounding distributed system. We force the model with field data from a lake drainage site, 70 km from the terminus of Russell Glacier in West Greenland. The model outputs suggest that efficient subglacial channels do not readily form in the vicinity of the lake during rapid drainage and instead water is evacuated primarily by a transient turbulent sheet and the distributed system. Following lake drainage, channels grow but are not large enough to reduce the water pressure in the surrounding distributed system, unless preexisting channels are present throughout the domain. Our results have implications for the analysis of subglacial hydrological systems in regions where rapid lake drainage provides the primary mechanism for surface-to-bed connections. Model for subglacial hydrological analysis of rapid lake drainage eventsLimited subglacial channel growth during and following rapid lake drainagePersistence of distributed drainage in inland areas where channel growth is limited.

Modeling of subglacial hydrological development following rapid supraglacial lake drainage

PubMed Central

Dow, C F; Kulessa, B; Rutt, I C; Tsai, V C; Pimentel, S; Doyle, S H; van As, D; Lindbäck, K; Pettersson, R; Jones, G A; Hubbard, A

2015-01-01

The rapid drainage of supraglacial lakes injects substantial volumes of water to the bed of the Greenland ice sheet over short timescales. The effect of these water pulses on the development of basal hydrological systems is largely unknown. To address this, we develop a lake drainage model incorporating both (1) a subglacial radial flux element driven by elastic hydraulic jacking and (2) downstream drainage through a linked channelized and distributed system. Here we present the model and examine whether substantial, efficient subglacial channels can form during or following lake drainage events and their effect on the water pressure in the surrounding distributed system. We force the model with field data from a lake drainage site, 70 km from the terminus of Russell Glacier in West Greenland. The model outputs suggest that efficient subglacial channels do not readily form in the vicinity of the lake during rapid drainage and instead water is evacuated primarily by a transient turbulent sheet and the distributed system. Following lake drainage, channels grow but are not large enough to reduce the water pressure in the surrounding distributed system, unless preexisting channels are present throughout the domain. Our results have implications for the analysis of subglacial hydrological systems in regions where rapid lake drainage provides the primary mechanism for surface-to-bed connections. Key Points Model for subglacial hydrological analysis of rapid lake drainage events Limited subglacial channel growth during and following rapid lake drainage Persistence of distributed drainage in inland areas where channel growth is limited PMID:26640746

Congenital absence of the portal vein: clinical and radiologic findings.

PubMed

Niwa, Tetsu; Aida, Noriko; Tachibana, Katsuhiko; Shinkai, Masato; Ohhama, Youkatsu; Fujita, Kazutoshi; Abe, Aya; Lee, Jin; Ozawa, Yukihiko; Inoue, Tomio

2002-01-01

Congenital absence of the portal vein (CAPV) is a rare anomaly in which the intestinal and splenic venous drainage bypasses the liver and drains into the systemic veins through various venous shunts. In patients with CAPV, the portosystemic shunting causes disruption of the enterohepatic circulation and leads to various clinical manifestations. CAPV can be diagnosed without invasive techniques. This article illustrates the clinical and radiologic findings (including ultrasound, CT, and MRI) of CAPV.

Surveying drainage culvert use by carnivores: sampling design and cost-benefit analyzes of track-pads vs. video-surveillance methods.

PubMed

Mateus, Ana Rita A; Grilo, Clara; Santos-Reis, Margarida

2011-10-01

Environmental assessment studies often evaluate the effectiveness of drainage culverts as habitat linkages for species, however, the efficiency of the sampling designs and the survey methods are not known. Our main goal was to estimate the most cost-effective monitoring method for sampling carnivore culvert using track-pads and video-surveillance. We estimated the most efficient (lower costs and high detection success) interval between visits (days) when using track-pads and also determined the advantages of using each method. In 2006, we selected two highways in southern Portugal and sampled 15 culverts over two 10-day sampling periods (spring and summer). Using the track-pad method, 90% of the animal tracks were detected using a 2-day interval between visits. We recorded a higher number of crossings for most species using video-surveillance (n = 129) when compared with the track-pad technique (n = 102); however, the detection ability using the video-surveillance method varied with type of structure and species. More crossings were detected in circular culverts (1 m and 1.5 m diameter) than in box culverts (2 m to 4 m width), likely because video cameras had a reduced vision coverage area. On the other hand, carnivore species with small feet such as the common genet Genetta genetta were detected less often using the track-pad surveying method. The cost-benefit analyzes shows that the track-pad technique is the most appropriate technique, but video-surveillance allows year-round surveys as well as the behavior response analyzes of species using crossing structures.

Sequential Gaussian co-simulation of rate decline parameters of longwall gob gas ventholes.

PubMed

Karacan, C Özgen; Olea, Ricardo A

2013-04-01

Gob gas ventholes (GGVs) are used to control methane inflows into a longwall mining operation by capturing the gas within the overlying fractured strata before it enters the work environment. Using geostatistical co-simulation techniques, this paper maps the parameters of their rate decline behaviors across the study area, a longwall mine in the Northern Appalachian basin. Geostatistical gas-in-place (GIP) simulations were performed, using data from 64 exploration boreholes, and GIP data were mapped within the fractured zone of the study area. In addition, methane flowrates monitored from 10 GGVs were analyzed using decline curve analyses (DCA) techniques to determine parameters of decline rates. Surface elevation showed the most influence on methane production from GGVs and thus was used to investigate its relation with DCA parameters using correlation techniques on normal-scored data. Geostatistical analysis was pursued using sequential Gaussian co-simulation with surface elevation as the secondary variable and with DCA parameters as the primary variables. The primary DCA variables were effective percentage decline rate, rate at production start, rate at the beginning of forecast period, and production end duration. Co-simulation results were presented to visualize decline parameters at an area-wide scale. Wells located at lower elevations, i.e., at the bottom of valleys, tend to perform better in terms of their rate declines compared to those at higher elevations. These results were used to calculate drainage radii of GGVs using GIP realizations. The calculated drainage radii are close to ones predicted by pressure transient tests.

Advances in Applications of Hierarchical Bayesian Methods with Hydrological Models

NASA Astrophysics Data System (ADS)

Alexander, R. B.; Schwarz, G. E.; Boyer, E. W.

2017-12-01

Mechanistic and empirical watershed models are increasingly used to inform water resource decisions. Growing access to historical stream measurements and data from in-situ sensor technologies has increased the need for improved techniques for coupling models with hydrological measurements. Techniques that account for the intrinsic uncertainties of both models and measurements are especially needed. Hierarchical Bayesian methods provide an efficient modeling tool for quantifying model and prediction uncertainties, including those associated with measurements. Hierarchical methods can also be used to explore spatial and temporal variations in model parameters and uncertainties that are informed by hydrological measurements. We used hierarchical Bayesian methods to develop a hybrid (statistical-mechanistic) SPARROW (SPAtially Referenced Regression On Watershed attributes) model of long-term mean annual streamflow across diverse environmental and climatic drainages in 18 U.S. hydrological regions. Our application illustrates the use of a new generation of Bayesian methods that offer more advanced computational efficiencies than the prior generation. Evaluations of the effects of hierarchical (regional) variations in model coefficients and uncertainties on model accuracy indicates improved prediction accuracies (median of 10-50%) but primarily in humid eastern regions, where model uncertainties are one-third of those in arid western regions. Generally moderate regional variability is observed for most hierarchical coefficients. Accounting for measurement and structural uncertainties, using hierarchical state-space techniques, revealed the effects of spatially-heterogeneous, latent hydrological processes in the "localized" drainages between calibration sites; this improved model precision, with only minor changes in regional coefficients. Our study can inform advances in the use of hierarchical methods with hydrological models to improve their integration with stream measurements.

Lymphatic drainage pathways from the cervix uteri: implications for radical hysterectomy?

PubMed

Kraima, A C; Derks, M; Smit, N N; Van Munsteren, J C; Van der Velden, J; Kenter, G G; DeRuiter, M C

2014-01-01

Radical hysterectomy with pelvic lymphadenectomy is the treatment of choice for early-stage cervical cancer. Wertheim's original technique has been often modified, mainly in the extent of parametrectomy. Okabayashi's technique is considered as the most radical variant regarding removal of the ventral parametrium and paracolpal tissues. Surgical outcome concerning recurrence and survival is good, but morbidity is high due to autonomic nerve damage. While the autonomic network has been studied extensively, the lymphatic system is less understood. This study describes the lymphatic drainage pathways of the cervix uteri and specifically the presence of lymphatics in the vesico-uterine ligament (VUL). A developmental series of 10 human female fetal pelves was studied. Paraffin embedded blocks were sliced in transverse sections of 8 or 10 μm. Analysis was performed by staining with antibodies against LYVE-1 (lymphatic endothelium), S100 (Schwann cells), alpha-Smooth Muscle Actin (smooth muscle cells) and CD68 (macrophages). The results were three-dimensionally represented. Two major pathways drained the cervix uteri: a supra-ureteral pathway, running in the cardinal ligament superior to the ureter, and a dorsal pathway, running in the utero-sacral ligament towards the rectal pillars. No lymph vessels draining the cervix uteri were detected in the VUL. In the paracolpal parametrium lymph vessels draining the upper vagina fused with those from the bladder. The VUL does not contain lymphatics from the cervix uteri. Hence, the favorable survival outcomes of the Okabayashi technique cannot be explained by radical removal of lymphatic pathways in the ventrocaudal parametrium. © 2013.

Sequential Gaussian co-simulation of rate decline parameters of longwall gob gas ventholes

USGS Publications Warehouse

Karacan, C. Özgen; Olea, Ricardo A.

2013-01-01

Gob gas ventholes (GGVs) are used to control methane inflows into a longwall mining operation by capturing the gas within the overlying fractured strata before it enters the work environment. Using geostatistical co-simulation techniques, this paper maps the parameters of their rate decline behaviors across the study area, a longwall mine in the Northern Appalachian basin. Geostatistical gas-in-place (GIP) simulations were performed, using data from 64 exploration boreholes, and GIP data were mapped within the fractured zone of the study area. In addition, methane flowrates monitored from 10 GGVs were analyzed using decline curve analyses (DCA) techniques to determine parameters of decline rates. Surface elevation showed the most influence on methane production from GGVs and thus was used to investigate its relation with DCA parameters using correlation techniques on normal-scored data. Geostatistical analysis was pursued using sequential Gaussian co-simulation with surface elevation as the secondary variable and with DCA parameters as the primary variables. The primary DCA variables were effective percentage decline rate, rate at production start, rate at the beginning of forecast period, and production end duration. Co-simulation results were presented to visualize decline parameters at an area-wide scale. Wells located at lower elevations, i.e., at the bottom of valleys, tend to perform better in terms of their rate declines compared to those at higher elevations. These results were used to calculate drainage radii of GGVs using GIP realizations. The calculated drainage radii are close to ones predicted by pressure transient tests.