Turbulent transport measurements with a laser Doppler velocimeter.

NASA Technical Reports Server (NTRS)

Edwards, R. V.; Angus, J. C.; Dunning, J. W., Jr.

1972-01-01

The power spectrum of phototube current from a laser Doppler velocimeter operating in the heterodyne mode has been computed. The spectral width and shape predicted by the theory are in agreement with experiment. For normal operating parameters the time-average spectrum contains information only for times shorter than the Lagrangian-integral time scale of the turbulence. To examine the long-time behavior, one must use either extremely small scattering angles, much-longer-wavelength radiation, or a different mode of signal analysis, e.g., FM detection.

Resident involvement in laparoscopic procedures does not worsen clinical outcomes but may increase operative times and length of hospital stay.

PubMed

Jolley, Jennifer; Lomelin, Daniel; Simorov, Anton; Tadaki, Carl; Oleynikov, Dmitry

2016-09-01

Surgical procedures have a learning curve regarding the number of cases required for proficiency. Consequently, involvement of less experienced resident surgeons may impact patients and the healthcare system. This study examines basic and advanced laparoscopic procedures performed between 2010 and 2011 and evaluates the resident surgeon participation effect. Basic laparoscopic procedures (BL), appendectomy (LA), cholecystectomy (LC), and advanced Nissen fundoplication (LN) were queried from the American College of Surgeons National Surgical Quality Improvement Program database. Cases were identified using Current Procedural Terminology codes. Analyses were performed using IBM SPSS Statistics v.22, α-level = 0.05. Multiple logistic regression was used, accounting for age, race, gender, admission status, wound classification, and ASA classification. In total, 71,819 surgeries were reviewed, 66,327 BL (37,636 LC and 28,691 LA) and 5492 LN. Median age was 48 years for LC and 37 years for LA. In sum, 72.2 % of LC and 49.5 % of LA patients were female. LN median age was 59 years, and 67.7 % of patients were female. For BL, resident involvement was not significantly associated with mortality, morbidity, and return to the OR. Readmission was not related to resident involvement in LC. In LA, resident-involved surgeries had increased readmission and longer OR time, but decreased LOS. In LC, resident involvement was associated with longer LOS and OR time. Resident involvement was not a significant factor in the odds of mortality, morbidity, return to OR, or readmission in LN. Surgeries involving residents had increased odds of having longer LOS, and of lengthier surgery time. We demonstrate resident involvement is safe and does not result in poorer patient outcomes. Readmissions and LOS were higher in BL, and operative times were longer in all surgeries. Resident operations do appear to have real consequences for patients and may impact the healthcare system financially.

A Proof of Factorization Theorem of Drell-Yan Process at Operator Level

NASA Astrophysics Data System (ADS)

Zhou, Gao-Liang

2016-02-01

An alternative proof of factorization theorem for Drell-Yan process that works at operator level is presented in this paper. Contributions of interactions after the hard collision for such inclusive processes are proved to be canceled at operator level according to the unitarity of time evolution operator. After this cancellation, there are no longer leading pinch singular surface in Glauber region in the time evolution of electromagnetic currents. Effects of soft gluons are absorbed into Wilson lines of scalar-polarized gluons. Cancelation of soft gluons is attribute to unitarity of time evolution operator and such Wilson lines. Supported by the National Natural Science Foundation of China under Grant No. 11275242

Relative to open surgery, minimally-invasive renal and ureteral pediatric surgery offers no improvement in 30-day complications, yet requires longer operative time: Data from the National Surgical Quality Improvement Program Pediatrics.

PubMed

Colaco, Marc; Hester, Austin; Visser, William; Rasper, Alison; Terlecki, Ryan

2018-05-01

Performance of minimally-invasive surgery (MIS) is increasing relative to open surgery. We sought to compare the contemporary rates of short-term complications of open versus laparoscopic renal and ureteral surgery in pediatric patients. A retrospective cross-sectional analysis of the National Surgical Quality Improvement Program Pediatrics database was performed of all cases in 2014 identified using CPT procedure codes for nephrectomy, partial nephrectomy (PN), ureteroneocystostomy (UNC), and pyeloplasty, and reviewed for postoperative complications. Univariate analysis was performed to determine 30-day complications, with comparison between open and MIS approaches. Receiver operator curve (ROC) analysis was performed to determine differences in body surface area (BSA) and age for open versus MIS. Review identified 207 nephrectomies, 72 PN, 920 UNC, and 625 pyeloplasties. MIS was associated with older age and larger BSA except for cases of UNC. Apart from PN, operative durations were longer with MIS. However, only PN was associated with significantly longer length of hospital stay (LOS). There was no difference in incidence of all other 30-day complications. When evaluating BSA via ROC, the area under the curve (AUC) was found to be 0.730 and was significant. Children with a BSA greater than 0.408 m 2 were more likely to have MIS (sensitivity, 66.9%; specificity, 69.3%). Regarding age, the AUC was 0.732. Children older than 637.5 days were more likely to have MIS (sensitivity, 72.8%; specificity, 63.3%). Pediatric MIS is associated with longer operative time for nephrectomy, but shorter LOS following PN. Surgical approach was not associated with difference in short-term complications.

Non-operative management is superior to surgical stabilization in spine injury patients with complete neurological deficits: A perspective study from a developing world country, Pakistan

PubMed Central

Shamim, Muhammad Shahzad; Ali, Syed Faizan; Enam, Syed Ather

2011-01-01

Background: Surgical stabilization of injured spine in patients with complete spinal cord injury is a common practice despite the lack of strong evidence supporting it. The aim of this study is to compare clinical outcomes and cost-effectiveness of surgical stabilization versus conservative management of spinal injury in patients with complete deficits, essentially from a developing country's point of view. Methods: A detailed analysis of patients with traumatic spine injury and complete deficits admitted at the Aga Khan University Hospital, Pakistan, from January 2004 till January 2010 was carried out. All patients presenting within 14 days of injury were divided in two groups, those who underwent stabilization procedures and those who were managed non-operatively. The two groups were compared with the endpoints being time to rehabilitation, length of hospital stay, 30 day morbidity/mortality, cost of treatment, and status at follow up. Results: Fifty-four patients fulfilled the inclusion criteria and half of these were operated. On comparing endpoints, patients in the operative group took longer time to rehabilitation (P-value = 0.002); had longer hospital stay (P-value = 0.006) which included longer length of stay in special care unit (P-value = 0.002) as well as intensive care unit (P-value = 0.004); and were associated with more complications, especially those related to infections (P-value = 0.002). The mean cost of treatment was also significantly higher in the operative group (USD 6,500) as compared to non-operative group (USD 1490) (P-value < 0.001). Conclusion: We recommend that patients with complete SCI should be managed non-operatively with a provision of surgery only if their rehabilitation is impeded due to pain or deformity. PMID:22145085

Non-operative management is superior to surgical stabilization in spine injury patients with complete neurological deficits: A perspective study from a developing world country, Pakistan.

PubMed

Shamim, Muhammad Shahzad; Ali, Syed Faizan; Enam, Syed Ather

2011-01-01

Surgical stabilization of injured spine in patients with complete spinal cord injury is a common practice despite the lack of strong evidence supporting it. The aim of this study is to compare clinical outcomes and cost-effectiveness of surgical stabilization versus conservative management of spinal injury in patients with complete deficits, essentially from a developing country's point of view. A detailed analysis of patients with traumatic spine injury and complete deficits admitted at the Aga Khan University Hospital, Pakistan, from January 2004 till January 2010 was carried out. All patients presenting within 14 days of injury were divided in two groups, those who underwent stabilization procedures and those who were managed non-operatively. The two groups were compared with the endpoints being time to rehabilitation, length of hospital stay, 30 day morbidity/mortality, cost of treatment, and status at follow up. Fifty-four patients fulfilled the inclusion criteria and half of these were operated. On comparing endpoints, patients in the operative group took longer time to rehabilitation (P-value = 0.002); had longer hospital stay (P-value = 0.006) which included longer length of stay in special care unit (P-value = 0.002) as well as intensive care unit (P-value = 0.004); and were associated with more complications, especially those related to infections (P-value = 0.002). The mean cost of treatment was also significantly higher in the operative group (USD 6,500) as compared to non-operative group (USD 1490) (P-value < 0.001). We recommend that patients with complete SCI should be managed non-operatively with a provision of surgery only if their rehabilitation is impeded due to pain or deformity.

Effect of Resident Involvement on Operative Time and Operating Room Staffing Costs.

PubMed

Allen, Robert William; Pruitt, Mark; Taaffe, Kevin M

The operating room (OR) is a major driver of hospital costs; therefore, operative time is an expensive resource. The training of surgical residents must include time spent in the OR, but that experience comes with a cost to the surgeon and hospital. The objective of this article is to determine the effect of surgical resident involvement in the OR on operative time and subsequent hospital labor costs. The Kruskal-Wallis statistical test is used to determine whether or not there is a difference in operative times between 2 groups of cases (with residents and without residents). This difference leads to an increased cost in associated hospital labor costs for the group with the longer operative time. Cases were performed at Greenville Memorial Hospital. Greenville Memorial Hospital is part of the larger healthcare system, Greenville Health System, located in Greenville, SC and is a level 1 trauma center with up to 33 staffed ORs. A total of 84,997 cases were performed at the partnering hospital between January 1st, 2011 and July 31st, 2015. Cases were only chosen for analysis if there was only one CPT code associated with the case and there were more than 5 observations for each group being studied. This article presents a comprehensive retrospective analysis of 29,134 cases covering 246 procedures. The analysis shows that 45 procedures took significantly longer with a resident present in the room. The average increase in operative time was 4.8 minutes and the cost per minute of extra operative time was determined to be $9.57 per minute. OR labor costs at the partnering hospital was found to be $2,257,433, or $492,889 per year. Knowing the affect on operative time and OR costs allows managers to make smart decisions when considering alternative educational and training techniques. In addition, knowing the connection between residents in the room and surgical duration could help provide better estimates of surgical time in the future and increase the predictability of procedure duration. Copyright © 2016 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

The impact of operative time on complications after plastic surgery: a multivariate regression analysis of 1753 cases.

PubMed

Hardy, Krista L; Davis, Kathryn E; Constantine, Ryan S; Chen, Mo; Hein, Rachel; Jewell, James L; Dirisala, Karunakar; Lysikowski, Jerzy; Reed, Gary; Kenkel, Jeffrey M

2014-05-01

Little evidence within plastic surgery literature supports the precept that longer operative times lead to greater morbidity. The authors investigate surgery duration as a determinant of morbidity, with the goal of defining a clinically relevant time for increased risk. A retrospective chart review was conducted of patients who underwent a broad range of complex plastic surgical procedures (n = 1801 procedures) at UT Southwestern Medical Center in Dallas, Texas, from January 1, 2008 to January 31, 2012. Adjusting for possible confounders, multivariate logistic regression assessed surgery duration as an independent predictor of morbidity. To define a cutoff for increased risk, incidence of complications was compared among quintiles of surgery duration. Stratification by type of surgery controlled for procedural complexity. A total of 1753 cases were included in multivariate analyses with an overall complication rate of 27.8%. Most operations were combined (75.8%), averaging 4.9 concurrent procedures. Each hour increase in surgery duration was associated with a 21% rise in odds of morbidity (P < .0001). Compared with the first quintile of operative time (<2.0 hours), there was no change in complications until after 3.1 hours of surgery (odds ratio, 1.6; P = .017), with progressively greater odds increases of 3.1 times after 4.5 hours (P < .0001) and 4.7 times after 6.8 hours (P < .0001). When stratified by type of surgery, longer operations continued to be associated with greater morbidity. Surgery duration is an independent predictor of complications, with a significantly increased risk above 3 hours. Although procedural complexity undoubtedly affects morbidity, operative time should factor into surgical decision making.

Getting started with robotics in general surgery with cholecystectomy: the Canadian experience

PubMed Central

Jayaraman, Shiva; Davies, Ward; Schlachta, Christopher M.

2009-01-01

Background The value of robotics in general surgery may be for advanced minimally invasive procedures. Unlike other specialties, formal fellowship training opportunities for robotic general surgery are few. As a result, most surgeons currently develop robotic skills in practice. Our goal was to determine whether robotic cholecystectomy is a safe and effective bridge to advanced robotics in general surgery. Methods Before performing advanced robotic procedures, 2 surgeons completed the Intuitive Surgical da Vinci training course and agreed to work together on all procedures. Clinical surgery began with da Vinci cholecystectomy with a plan to begin advanced procedures after at least 10 cholecystectomies. We performed a retrospective review of our pilot series of robotic cholecystectomies and compared them with contemporaneous laparoscopic controls. The primary outcome was safety, and the secondary outcome was learning curve. Results There were 16 procedures in the robotics arm and 20 in the laparoscopic arm. Two complications (da Vinci port-site hernia, transient elevation of liver enzymes) occurred in the robotic arm, whereas only 1 laparoscopic patient (slow to awaken from anesthetic) experienced a complication. None was significant. The mean time required to perform robotic cholecystectomy was significantly longer than laparoscopic surgery (91 v. 41 min, p < 0.001). The mean time to clear the operating room was significantly longer for robotic procedures (14 v. 11 min, p = 0.015). We observed a trend showing longer mean anesthesia time for robotic procedures (23 v. 15 min). Regarding learning curve, the mean operative time needed for the first 3 robotic procedures was longer than for the last 3 (101 v. 80 min); however, this difference was not significant. Since this experience, the team has confidently gone on to perform robotic biliary, pancreatic, gastresophageal, intestinal and colorectal operations. Conclusion Robotic cholecystectomy can be performed reliably; however, owing to the significant increase in operating room resources, it cannot be justified for routine use. Our experience, however, demonstrates that robotic cholecystectomy is one means by which general surgeons may gain confidence in performing advanced robotic procedures. PMID:19865571

A Prospective Comparison of Robotic and Laparoscopic Pyeloplasty

PubMed Central

Link, Richard E.; Bhayani, Sam B.; Kavoussi, Louis R.

2006-01-01

Objective: To determine whether robotic-assisted pyeloplasty (RLP) has any significant clinical or cost advantages over laparoscopic pyeloplasty (LP) for surgeons already facile with intracorporeal suturing. Summary Background Data: LP has become an established management approach for primary ureteropelvic junction obstruction. More recently, the da Vinci robot has been applied to this procedure (RLP) in an attempt to shorten the learning curve. Whether RLP provides any significant advantage over LP for the experienced laparoscopist remains unclear. Methods: Ten consecutive cases each of transperitoneal RLP and LP performed by a single surgeon were compared prospectively with respect to surgical times and perioperative outcomes. Cost assessment was performed by sensitivity analysis using a mathematical cost model incorporating operative time, anesthesia fees, consumables, and capital equipment depreciation. Results: The RLP and LP groups had statistically indistinguishable demographics, pathology, and similar perioperative outcomes. Mean operative and total room time for RLP was significantly longer than LP by 19.5 and 39.0 minutes, respectively. RLP was much more costly than LP (2.7 times), due to longer operative time, increased consumables costs, and depreciation of the costly da Vinci system. However, even if depreciation was eliminated, RLP was still 1.7 times as costly as LP. One-way sensitivity analysis showed that LP operative time must increase to almost 6.5 hours for it to become cost equivalent to RLP. Conclusions: For the experienced laparoscopist, application of the da Vinci robot resulted in no significant clinical advantage and added substantial cost to transperitoneal laparoscopic dismembered pyeloplasty. PMID:16552199

A prospective comparison of robotic and laparoscopic pyeloplasty.

PubMed

Link, Richard E; Bhayani, Sam B; Kavoussi, Louis R

2006-04-01

To determine whether robotic-assisted pyeloplasty (RLP) has any significant clinical or cost advantages over laparoscopic pyeloplasty (LP) for surgeons already facile with intracorporeal suturing. LP has become an established management approach for primary ureteropelvic junction obstruction. More recently, the da Vinci robot has been applied to this procedure (RLP) in an attempt to shorten the learning curve. Whether RLP provides any significant advantage over LP for the experienced laparoscopist remains unclear. Ten consecutive cases each of transperitoneal RLP and LP performed by a single surgeon were compared prospectively with respect to surgical times and perioperative outcomes. Cost assessment was performed by sensitivity analysis using a mathematical cost model incorporating operative time, anesthesia fees, consumables, and capital equipment depreciation. The RLP and LP groups had statistically indistinguishable demographics, pathology, and similar perioperative outcomes. Mean operative and total room time for RLP was significantly longer than LP by 19.5 and 39.0 minutes, respectively. RLP was much more costly than LP (2.7 times), due to longer operative time, increased consumables costs, and depreciation of the costly da Vinci system. However, even if depreciation was eliminated, RLP was still 1.7 times as costly as LP. One-way sensitivity analysis showed that LP operative time must increase to almost 6.5 hours for it to become cost equivalent to RLP. For the experienced laparoscopist, application of the da Vinci robot resulted in no significant clinical advantage and added substantial cost to transperitoneal laparoscopic dismembered pyeloplasty.

Influence of the charge double layer on solid oxide fuel cell stack behavior

NASA Astrophysics Data System (ADS)

Whiston, Michael M.; Bilec, Melissa M.; Schaefer, Laura A.

2015-10-01

While the charge double layer effect has traditionally been characterized as a millisecond phenomenon, longer timescales may be possible under certain operating conditions. This study simulates the dynamic response of a previously developed solid oxide fuel cell (SOFC) stack model that incorporates the charge double layer via an equivalent circuit. The model is simulated under step load changes. Baseline conditions are first defined, followed by consideration of minor and major deviations from the baseline case. This study also investigates the behavior of the SOFC stack with a relatively large double layer capacitance value, as well as operation of the SOFC stack under proportional-integral (PI) control. Results indicate that the presence of the charge double layer influences the SOFC stack's settling time significantly under the following conditions: (i) activation and concentration polarizations are significantly increased, or (ii) a large value of the double layer capacitance is assumed. Under normal (baseline) operation, on the other hand, the charge double layer effect diminishes within milliseconds, as expected. It seems reasonable, then, to neglect the charge double layer under normal operation. However, careful consideration should be given to potential variations in operation or material properties that may give rise to longer electrochemical settling times.

Qubits and quantum Hamiltonian computing performances for operating a digital Boolean 1/2-adder

NASA Astrophysics Data System (ADS)

Dridi, Ghassen; Faizy Namarvar, Omid; Joachim, Christian

2018-04-01

Quantum Boolean (1 + 1) digits 1/2-adders are designed with 3 qubits for the quantum computing (Qubits) and 4 quantum states for the quantum Hamiltonian computing (QHC) approaches. Detailed analytical solutions are provided to analyse the time operation of those different 1/2-adder gates. QHC is more robust to noise than Qubits and requires about the same amount of energy for running its 1/2-adder logical operations. QHC is faster in time than Qubits but its logical output measurement takes longer.

Sensitivity of chemistry-transport model simulations to the duration of chemical and transport operators: a case study with GEOS-Chem v10-01

NASA Astrophysics Data System (ADS)

Philip, Sajeev; Martin, Randall V.; Keller, Christoph A.

2016-05-01

Chemistry-transport models involve considerable computational expense. Fine temporal resolution offers accuracy at the expense of computation time. Assessment is needed of the sensitivity of simulation accuracy to the duration of chemical and transport operators. We conduct a series of simulations with the GEOS-Chem chemistry-transport model at different temporal and spatial resolutions to examine the sensitivity of simulated atmospheric composition to operator duration. Subsequently, we compare the species simulated with operator durations from 10 to 60 min as typically used by global chemistry-transport models, and identify the operator durations that optimize both computational expense and simulation accuracy. We find that longer continuous transport operator duration increases concentrations of emitted species such as nitrogen oxides and carbon monoxide since a more homogeneous distribution reduces loss through chemical reactions and dry deposition. The increased concentrations of ozone precursors increase ozone production with longer transport operator duration. Longer chemical operator duration decreases sulfate and ammonium but increases nitrate due to feedbacks with in-cloud sulfur dioxide oxidation and aerosol thermodynamics. The simulation duration decreases by up to a factor of 5 from fine (5 min) to coarse (60 min) operator duration. We assess the change in simulation accuracy with resolution by comparing the root mean square difference in ground-level concentrations of nitrogen oxides, secondary inorganic aerosols, ozone and carbon monoxide with a finer temporal or spatial resolution taken as "truth". Relative simulation error for these species increases by more than a factor of 5 from the shortest (5 min) to longest (60 min) operator duration. Chemical operator duration twice that of the transport operator duration offers more simulation accuracy per unit computation. However, the relative simulation error from coarser spatial resolution generally exceeds that from longer operator duration; e.g., degrading from 2° × 2.5° to 4° × 5° increases error by an order of magnitude. We recommend prioritizing fine spatial resolution before considering different operator durations in offline chemistry-transport models. We encourage chemistry-transport model users to specify in publications the durations of operators due to their effects on simulation accuracy.

Turbulent transport measurements with a laser Doppler velocimeter

NASA Technical Reports Server (NTRS)

Edwards, R. V.; Angus, J. C.; Dunning, J. W., Jr.

1972-01-01

The power spectrum of phototube current from a laser Doppler velocimeter operating in the heterodyne mode has been computed. The spectrum is obtained in terms of the space time correlation function of the fluid. The spectral width and shape predicted by the theory are in agreement with experiment. For normal operating parameters the time average spectrum contains information only for times shorter than the Lagrangian integral time scale of the turbulence. To examine the long time behavior, one must use either extremely small scattering angles, much longer wavelength radiation or a different mode of signal analysis, e.g., FM detection.

Longer Operative Time During Benign Laparoscopic and Robotic Hysterectomy Is Associated With Increased 30-Day Perioperative Complications.

PubMed

Catanzarite, Tatiana; Saha, Sujata; Pilecki, Matthew A; Kim, John Y S; Milad, Magdy P

2015-01-01

The relationship between operative time and perioperative morbidity has not been fully characterized in gynecology. We aimed to determine the impact of operative time on 30-day perioperative complications after laparoscopic and robotic hysterectomy. Patients undergoing laparoscopic and robotic hysterectomy for benign disease from 2006 to 2011 within the National Surgical Quality Improvement Program (NSQIP) database were identified by Current Procedural Terminology code. Operative times were stratified into 60-minute intervals and complication rates analyzed. Primary outcomes included 30-day overall, medical, and surgical complications. Bivariate analyses using χ(2), Fisher's exact, and one-way analysis of variance tests were performed to compare clinical and procedural characteristics associated with longer operative time and complications. Multivariable logistic regression analyses were then performed to determine the independent association between operative time and perioperative complications. Canadian Task Force classification II-2 (Evidence obtained from well-designed cohort or case-control studies preferably from more than 1 center or research group). American College of Surgeons NSQIP. Patients who underwent laparoscopic or robotic hysterectomy for benign disease from 2006 to 2011 at any institution participating in NSQIP. None, retrospective database study. Of the 7630 laparoscopic and robotic hysterectomies identified, 399 patients (5.2%) experienced complications, most commonly urinary tract infection (UTI; 2.1%), superficial surgical site infection (1.0%), and blood transfusion (1.0%). Return to the operating room was required in 97 patients (1.3%), and there were 4 deaths, for a mortality rate of .05%. Complications increased steadily with longer operative time. Operative time ≥ 240 minutes was associated with increased overall complications (13.8% vs 4.6%, p < .001), surgical complications (5.4% vs 1.5%, p < .001), medical complications (10.4% vs 3.2%, p < .001), return to the operating room (2.7% vs 1.2%, p = .002), deep venous thrombosis (.5% vs .06%, p = .011), pulmonary embolism (.7% vs .1%, p = .012), and blood transfusion (3.4% vs .8%, p < .001). These associations remained statistically significant after multivariable regression analysis. Based on continuous regression modeling, each additional hour of operative time would be expected to increase odds of overall complications (odds ratio [OR], 1.4; 95% confidence interval [CI], 1.28-1.54; p < .001), medical complications (OR, 1.42; 95% CI, 1.28-1.57; p < .001), surgical complications (OR, 1.32; 95% CI, 1.17-1.49; p < .001), venous thromboembolism (OR, 1.47; 95% CI, 1.12-1.92; p = .005), UTI (OR, 1.20; 95% CI, 1.05-1.36; p = .006), blood transfusion (OR, 1.42; 95% CI, 1.18-1.71; p < .001), and return to the operating room (OR, 1.25; 95% CI, 1.08-1.45; p = .003). We demonstrated a direct, independent association between operative time and 30-day complications after laparoscopic and robotic hysterectomy. Future research should aim to further delineate risk factors for prolonged operative time and morbidity in laparoscopic hysterectomy to allow surgeons to maximize preoperative planning and optimize patient selection for minimally invasive hysterectomy. Copyright © 2015 AAGL. Published by Elsevier Inc. All rights reserved.

Laparoscopic colectomy in the obese, morbidly obese, and super morbidly obese: when does weight matter?

PubMed

Champagne, Bradley J; Nishtala, Madhuri; Brady, Justin T; Crawshaw, Benjamin P; Franklin, Morris E; Delaney, Conor P; Steele, Scott R

2017-10-01

Previous studies have demonstrated that obese patients (BMI >30) undergoing laparoscopic colectomy have longer operative times and increased complications when compared to non-obese cohorts. However, there is little data that specifically evaluates the outcomes of obese patients based on the degree of their obesity. The aim of this study was to evaluate the impact of increasing severity of obesity on patients undergoing laparoscopic colectomy. A retrospective review was performed of all patients undergoing laparoscopic colectomy between 1996 and 2013. Patients were classified according to their BMI as obese (BMI 30.0-39.9), morbidly obese (BMI 40.0-49.9), and super obese (BMI >50). Main outcome measures included conversion rate, operative time, estimated blood loss, post-operative complications, and length of stay. There were 923 patients who met inclusion criteria. Overall, 604 (65.4%), 257 (27.9%), and 62 (6.7%) were classified as obese (O), morbidly obese (MO), and super obese (SO), respectively. Clinicopathologic characteristics were similar among the three groups. The SO group had significantly higher conversion rates (17.7 vs. 7 vs. 4.8%; P = 0.031), longer average hospital stays (7.1 days vs. 4.9 vs. 3.4; P = 0.001), higher morbidity (40.3 vs. 16.3 vs. 12.4%; P = 0.001), and longer operative times (206 min vs. 184 vs. 163; P = 0.04) compared to the MO and O groups, respectively. The anastomotic leak rate in the SO (4.8%; P = 0.027) and MO males (4.1%; P = 0.033) was significantly higher than MO females (2.2%) and all obese patients (1.8%). Increasing severity of obesity is associated with worse perioperative outcomes following laparoscopic colectomy.

A sorting system with automated gates permits individual operant experiments with mice from a social home cage.

PubMed

Winter, York; Schaefers, Andrea T U

2011-03-30

Behavioral experiments based on operant procedures can be time-consuming for small amounts of data. While individual testing and handling of animals can influence attention, emotion, and behavior, and interfere with experimental outcome, many operant protocols require individual testing. We developed an RFID-technology- and transponder-based sorting system that allows removing the human factor for longer-term experiments. Identity detectors and automated gates route mice individually from their social home cage to an adjacent operant compartment with 24/7 operation. CD1-mice learnt quickly to individually pass through the sorting system. At no time did more than a single mouse enter the operant compartment. After 3 days of adjusting to the sorting system, groups of 4 mice completed about 50 experimental trials per day in the operant compartment without experimenter intervention. The automated sorting system eliminates handling, isolation, and disturbance of the animals, eliminates experimenter-induced variability, saves experimenter time, and is financially economical. It makes possible a new approach for high-throughput experimentation, and is a viable tool for increasing quality and efficiency of many behavioral and neurobiological investigations. It can connect a social home cage, through individual sorting automation, to diverse setups including classical operant chambers, mazes, or arenas with video-based behavior classification. Such highly automated systems will permit efficient high-throughput screening even for transgenic animals with only subtle neurological or psychiatric symptoms where elaborate or longer-term protocols are required for behavioral diagnosis. Copyright © 2011 Elsevier B.V. All rights reserved.

Extended Operation of Turbojet Engine with Pentaborane

NASA Technical Reports Server (NTRS)

Useller, James W; Jones, William L

1957-01-01

A full-scale turbojet engine was operated with pentaborane fuel continuously for 22 minutes at conditions simulating flight at a Mach number of 0.8 at an altitude of 50,000 feet. This period of operation is approximately three times longer than previously reported operation times. Although the specific fuel consumption was reduced from 1.3 with JP-4 fuel to 0.98 with pentaborane, a 13.2-percent reduction in net thrust was also encountered. A portion of this thrust loss is potentially recoverable with proper design of the engine components. The boron oxide deposition and erosion processes within the engine approached an equilibrium condition after approximately 22 minutes of operation with pentaborane.

Automatic updating of times remaining in surgical cases using bayesian analysis of historical case duration data and "instant messaging" updates from anesthesia providers.

PubMed

Dexter, Franklin; Epstein, Richard H; Lee, John D; Ledolter, Johannes

2009-03-01

Operating room (OR) whiteboards (status displays) communicate times remaining for ongoing cases to perioperative stakeholders (e.g., postanesthesia care unit, anesthesiologists, holding area, and control desks). Usually, scheduled end times are shown for each OR. However, these displays are inaccurate for predicting the time that remains in a case. Once a case scheduled for 2 h has been on-going for 1.5 h, the median time remaining is not 0.5 h but longer, and the amount longer differs among procedures. We derived the conditional Bayesian lower prediction bound of a case's duration, conditional on the minutes of elapsed OR time. Our derivations make use of the posterior predictive distribution of OR times following an exponential of a scaled Student t distribution that depends on the scheduled OR time and several parameters calculated from historical case duration data. The statistical method was implemented using Structured Query Language (SQL) running on the anesthesia information management system (AIMS) database server. In addition, AIMS workstations were sent instant messages displaying a pop-up dialog box asking for anesthesia providers' estimates for remaining times. The dialogs caused negotiated interruptions (i.e., the anesthesia provider could reply immediately, keep the dialog displayed, or defer response). There were no announcements, education, or efforts to promote buy-in. After a case had been in the OR longer than scheduled, the median remaining OR time for the case changes little over time (e.g., 35 min left at 2:30 pm and also at 3:00 pm while the case was still on-going). However, the remaining time differs substantially among surgeons and scheduled procedure(s) (16 min longer [10th percentile], 35 min [50th], and 86 min [90th]). We therefore implemented an automatic method to estimate the times remaining in cases. The system was operational for >119 of each day's 120 5-min intervals. When instant message dialogs appearing on AIMS workstations were used to elicit estimates of times remaining from anesthesia providers, acknowledgment was on average within 1.2 min (95% confidence interval [CI] 1.1-1.3 min). The 90th percentile of latencies was 6.5 min (CI: 4.4-7.0 min). For cases taking nearly as long as or longer than scheduled, each 1 min progression of OR time reduces the median time remaining in a case by <1 min. We implemented automated calculation of times remaining for every case at a 29 OR hospital.

Predictors of Operative Mortality for Coronary Bypass Grafting in Patients with Ischemic Heart Disease

PubMed Central

Langou, Rene A.; Wiles, John C.; Peduzzi, Peter N.; Hammond, Graeme; Cohen, Lawrence S.

1978-01-01

Predictors for operative mortality (OM) were studied in 172 consecutive patients (pts) undergoing coronary artery grafts (CAG) for angina pectoris. Seventy eight pts had Class IV angina; of the 147 patients given propranolol, 41 were gradually withdrawn from propranolol and finally discontinued 24 hours before surgery, and 106 were abruptly withdrawn from propranolol 24 hours before CAG; 20 pts had left main coronary disease; 156 pts had cardiopulmonary bypass (CPB) time shorter than 20 minutes, and 16 pts had a CPB longer than 120 minutes. The operative mortality was 5.2% (9/172) for the entire group. Class IV angina (OM 7%), abrupt propranolol withdrawal (OM 6.6%), left main coronary artery disease (OM 25%), and CPB longer than 120 minutes (OM 50%), all significantly increased OM. These variables were interdependent, however, as many pts belonged to several predictor categories, combinations of predictors were examined, in order to more accurately predict the risk of individual pts. The combination of left main coronary artery disease and CPB longer than 120 minutes; and Class IV angina and CPB longer than 120 minutes were significantly associated with higher operative mortality. We conclude that Class IV angina, abrupt propranolol withdrawal, left main coronary artery disease and prolonged CPB are potent, interdependent predictors of OM in pts undergoing CAG. Consideration of these predictors, alone and in combination, allows effective prediction of OM for CAG in patients with stable angina pectoris. PMID:307873

An assessment of the quality indicators of operative and non-operative times in a public university hospital.

PubMed

Costa, Altair da Silva; Leão, Luiz Eduardo Villaça; Novais, Maykon Anderson Pires de; Zucchi, Paola

2015-01-01

To assess the operative time indicators in a public university hospital. A descriptive cross-sectional study was conducted using data from operating room database. The sample was obtained from January 2011 to January 2012. The operations performed in sequence in the same operating room, between 7:00 am and 5:00 pm, elective or emergency, were included. The procedures with incomplete data in the system were excluded, as well as the operations performed after 5:00 pm or on weekends or holidays. We measured the operative and non-operative time of 8,420 operations. The operative time (mean and standard deviation) of anesthesias and operations were 177.6 ± 110 and 129.8 ± 97.1 minutes, respectively. The total time of the patient in operative room (mean and standard deviation) was 196.8 ± 113.2. The non-operative time, e.g., between the arrival of the patient and the onset of anesthesia was 14.3 ± 17.3 minutes. The time to set the next patient in operating room was 119.8 ± 79.6 minutes. Our total non-operative time was 155 minutes. Delays frequently occurred in our operating room and had a major effect on patient flow and resource utilization. The non-operative time was longer than the operative time. It is possible to increase the operating room capacity by management and training of the professionals involved. The indicators provided a tool to improve operating room efficiency.

40 CFR 63.1952 - When am I no longer required to comply with the requirements of this subpart if I own or operate...

Code of Federal Regulations, 2011 CFR

2011-07-01

... with the requirements of this subpart if I own or operate a bioreactor? 63.1952 Section 63.1952... longer required to comply with the requirements of this subpart if I own or operate a bioreactor? If you own or operate a landfill that includes a bioreactor, you are no longer required to comply with the...

40 CFR 63.1952 - When am I no longer required to comply with the requirements of this subpart if I own or operate...

Code of Federal Regulations, 2010 CFR

2010-07-01

... with the requirements of this subpart if I own or operate a bioreactor? 63.1952 Section 63.1952... longer required to comply with the requirements of this subpart if I own or operate a bioreactor? If you own or operate a landfill that includes a bioreactor, you are no longer required to comply with the...

Protected quantum computing: interleaving gate operations with dynamical decoupling sequences.

PubMed

Zhang, Jingfu; Souza, Alexandre M; Brandao, Frederico Dias; Suter, Dieter

2014-02-07

Implementing precise operations on quantum systems is one of the biggest challenges for building quantum devices in a noisy environment. Dynamical decoupling attenuates the destructive effect of the environmental noise, but so far, it has been used primarily in the context of quantum memories. Here, we experimentally demonstrate a general scheme for combining dynamical decoupling with quantum logical gate operations using the example of an electron-spin qubit of a single nitrogen-vacancy center in diamond. We achieve process fidelities >98% for gate times that are 2 orders of magnitude longer than the unprotected dephasing time T2.

A venturi device reduces membrane fouling in a submerged membrane bioreactor.

PubMed

Kayaalp, Necati; Ozturkmen, Gokmen

2016-01-01

In this study, for the first time, a venturi device was integrated into a submerged membrane bioreactor (MBR) to improve membrane surface cleaning and bioreactor oxygenation. The performances of a blower and the venturi device were compared in terms of membrane fouling and bioreactor oxygenation. Upon comparing membrane fouling, the performances were similar for a low operation flux (18 L/m(2).h); however, at a medium flux (32 L/m(2).h), the venturi system operated 3.4 times longer than the blower system, and the final transmembrane pressure was one-third that of the blower system. At the highest flux studied (50 L/m(2).h), the venturi system operated 5.4 times longer than the blower system. The most notable advantage of using a venturi device was that the dissolved oxygen (DO) concentration of the MBR was in the range of 7 to 8 mg/L at a 3 L/min aeration rate, while the DO concentration of the MBR was inadequate (a maximum of 0.29 mg/L) in the blower system. A clean water oxygenation test at a 3 L/min aeration rate indicated that the standard oxygen transfer rate for the venturi system was 9.5 times higher than that of the blower system.

Preoperative fasting times in elective surgical patients at a referral Hospital in Botswana.

PubMed

Abebe, Worknehe Agegnehu; Rukewe, Ambrose; Bekele, Negussie Alula; Stoffel, Moeng; Dichabeng, Mompelegi Nicoh; Shifa, Jemal Zeberga

2016-01-01

Adults and children are required to fast before anaesthesia to reduce the risk of regurgitation and aspiration of gastric contents. However, prolonged periods of fasting are unnecessary and may cause complications. This study was conducted to evaluate preoperative fasting period in our centre and compare it with the ASA recommendations and factors that influence fasting periods. This is a cross-sectional study of preoperative fasting times among elective surgical patients. A total numbers of 260 patients were interviewed as they arrived at the reception area of operating theatre using questionnaire. Majority of patients (98.1%) were instructed to fast from midnight. Fifteen patients (5.8%) reported that they were told the importance of preoperative fasting. The mean fasting period were 15.9±2.5 h (range 12.0-25.3 h) for solids and 15.3±2.3 h (range 12.0-22.0 h) for liquids. The mean duration of fasting was significantly longer for patients operated after midday compared to those operated before midday, p<0.001. The mean fasting periods were 7.65 times longer for clear liquid and 2.5 times for solids than the ASA guidelines. It is imperative that the Hospital should establish Preoperative fasting policies and teach the staff who should ensure compliance with guidelines.

An improved APU for the Space Shuttle Orbiter

NASA Technical Reports Server (NTRS)

Mckenna, R.; Hagemann, D.; Loken, G.; Jonakin, J.; Baughman, J.

1985-01-01

The Space Shuttle Orbiter Auxiliary Power Unit has operated successfully on all four orbiter vehicles and all missions. The current Auxiliary Power Unit (APU) operational life is limited to 12 missions, and the APU turnaround time between flights is longer than originally anticipated. The objective of the Improved APU program is to increase life to 50 missions, reduce installed vehicle weight by 134 lb., and reduce turnaround time. This paper describes the design changes incorporated into the improved APU and the associated development testing.

77 FR 841 - Taking and Importing Marine Mammals: Taking Marine Mammals Incidental to U.S. Navy Operations of...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-01-06

... threats is decreasing, and at the same time, improvements in torpedo design are extending the effective... relatively short period of time. It is likely that any marine mammal would be able to avoid the surveillance... duration of any continuous frequency sound transmission is no longer than 10 sec and the time between pings...

Systematic review of perioperative outcomes and complications after open, laparoscopic and robot-assisted radical cystectomy.

PubMed

Palazzetti, A; Sanchez-Salas, R; Capogrosso, P; Barret, E; Cathala, N; Mombet, A; Prapotnich, D; Galiano, M; Rozet, F; Cathelineau, X

2017-09-01

Radical cystectomy and regional lymph node dissection is the standard treatment for localized muscle-invasive and for high-risk non-muscle-invasive bladder cancer, and represents one of the main surgical urologic procedures. The open surgical approach is still widely adopted, even if in the last two decades efforts have been made in order to evaluate if minimally invasive procedures, either laparoscopic or robot-assisted, might show a benefit compared to the standard technique. Open radical cystectomy is associated with a high complication rate, but data from the laparoscopic and robotic surgical series failed to demonstrate a clear reduction in post-operative complication rates compared to the open surgical series. Laparoscopic and robotic radical cystectomy show a reduction in blood loss, in-hospital stay and transfusion rates but a longer operative time, while open radical cystectomy is typically associated with a shorter operative time but with a longer in-hospital admission and possibly a higher rate of high grade complications. Copyright © 2016. Publicado por Elsevier España, S.L.U.

Defense Acquisitions. Assessment of DOD Efforts to Enhance Missile Defense Capabilities and Oversight

DTIC Science & Technology

2008-02-26

will no longer defer work from one block to another. Accountability should also be improved as MDA will for the first time estimate unit costs for... costs are no longer accounted for in the original block. In other words, if work planned and budgeted for Block 2006 was deferred to Block 2008, that...difficult to conduct oversight and hold the agency accountable for its planned outcomes and costs . As we reported in March 2007, MDA operates with

Cystic meconium peritonitis with jejunoileal atresia: Is it associated with unfavorable outcome?

PubMed Central

Chan, Kin Wai Edwin; Lee, Kim Hung; Wong, Hei Yi Vicky; Tsui, Siu Yan Bess; Wong, Yuen Shan; Pang, Kit Yi Kristine; Mou, Jennifer Wai Cheung; Tam, Yuk Him

2017-01-01

AIM To compare the outcome between patients with jejunoileal atresia (JIA) associated with cystic meconium peritonitis (CMP) and patients with isolated JIA (JIA without CMP). METHODS A retrospective study was conducted for all neonates with JIA operated in our institute from January 2005 to January 2016. Demographics including the gestation age, sex, birth weight, age at operation, the presence of associated syndrome was recorded. Clinical outcome including the type of operation performed, operative time, the need for reoperation and mortality were studied. The demographics and the outcome between the 2 groups were compared. RESULTS During the study period, 53 neonates had JIA underwent operation in our institute. Seventeen neonates (32%) were associated with CMP. There was no statistical difference on the demographics in the two groups. Patients with CMP had earlier operation than patients with isolated JIA (mean 1.4 d vs 3 d, P = 0.038). Primary anastomosis was performed in 16 patients (94%) with CMP and 30 patients (83%) with isolated JIA (P = 0.269). Patients with CMP had longer operation (mean 190 min vs 154 min, P = 0.004). There were no statistical difference the need for reoperation (3 vs 6, P = 0.606) and mortality (2 vs 1, P = 0.269) between the two groups. CONCLUSION Primary intestinal anastomosis can be performed in 94% of patients with JIA associated with CMP. Although patients with CMP had longer operative time, the mortality and reoperation rates were low and were comparable to patients with isolated JIA. PMID:28224094

Radiofrequency ablation versus electrocautery in tonsillectomy.

PubMed

Hall, Daniel J; Littlefield, Philip D; Birkmire-Peters, Deborah P; Holtel, Michael R

2004-03-01

The objective of this study was to compare the safety, difficulty of removal, and postoperative pain profile of radiofrequency ablation versus standard electrocautery removal of tonsils. A prospective, blinded study was designed to remove 1 tonsil with each of the 2 methods. Time of operation, estimated blood loss, difficulty of operation, postoperative pain, rate of postoperative hemorrhage, and the patient's preferred technique were evaluated. The operating time was significantly longer (P < 0.007) and the patients reported significantly less pain (P < 0.001) with radiofrequency ablation. There were no differences in blood loss, difficulty of operation, or postoperative hemorrhage rates. The patients preferred the radiofrequency ablation technique (P < 0.001). Radiofrequency ablation is a viable method to remove tonsillar tissue. Operating time for this procedure will likely decrease with experience. There was significantly less pain reported with radiofrequency ablation compared with standard electrocautery.

ADVANCEMENT OF THE RHIC BEAM ABORT KICKER SYSTEM.

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

ZHANG,W.AHRENS,L.MI,J.OERTER,B.SANDBERG,J.WARBURTON,D.

2003-05-12

As one of the most critical system for RHIC operation, the beam abort kicker system has to be highly available, reliable, and stable for the entire operating range. Along with the RHIC commission and operation, consistent efforts have been spend to cope with immediate issues as well as inherited design issues. Major design changes have been implemented to achieve the higher operating voltage, longer high voltage hold-off time, fast retriggering and redundant triggering, and improved system protection, etc. Recent system test has demonstrated for the first time that both blue ring and yellow ring beam abort systems have achieved moremore » than 24 hours hold off time at desired operating voltage. In this paper, we report break down, thyratron reverse arcing, and to build a fast re-trigger system to reduce beam spreading in event of premature discharge.« less

Surgical treatment of distal tibia fractures: open versus MIPO.

PubMed

Gülabi, Deniz; Bekler, Halil İbrahim; Sağlam, Fevzi; Taşdemir, Zeki; Çeçen, Gültekin Sıtkı; Elmalı, Nurzat

2016-01-01

Treatment of the distal tibial fractures are challenging due to the limited soft tissue, subcutaneous location and poor vascularity. In this control-matched study, it was aimed to compare the traditional open reduction and internal fixation with minimal invasive plating (MIPO). We hypothesized that superior results may be achieved with MIPO technique. 22 patients treated with traditional open reduction and internal fixation were matched with 22 patients treated with closed reduction and MIPO on the basis of age (±3), gender, and fracture pattern (AO classification). Evaluation was assed according to the wound problems, the American Orthopaedic Foot and Ankle surgery (AOFAS) scoring, radiological union, malunion, delayed union, hospitalisation time, time from injury to surgery, and operation time. There was no significant difference in the distribution of AO/OTA classification, age, gender, AOFAS score, time from injury to operation, follow-up, bone union time, delayed union, malunion and infection (p>0.05). The operation time was significantly longer in the open group than in the MIPO group: 69.59±7.21 min. for the ORIF, and 61.14±5.61 for the MIPO group (p<0.01).The hospitalisation time was significantly longer in the open group than in the MIPO group: 7.64±4.71 days for the MIPO, and 10.18±4.32 days for the ORIF group (p<0.05). MIPO technique can be beneficial for the treatment of distal tibia AO/OTA A and B type fractures with reduced hospital stay, cost-effectiveness, and infection rate.

Surgical outcomes of robotic-assisted surgical staging for endometrial cancer are equivalent to traditional laparoscopic staging at a minimally invasive surgical center

PubMed Central

Cardenas-Goicoechea, Joel; Adams, Sarah; Bhat, Suneel B.; Randall, Thomas C.

2010-01-01

Objective To compare peri- and post-operative complications and outcomes of robotic-assisted surgical staging with traditional laparoscopic surgical staging for women with endometrial cancer. Methods A retrospective chart review of cases of women undergoing minimally invasive total hysterectomy and pelvic and para-aortic lymphadenectomy by a robotic-assisted approach or traditional laparoscopic approach was conducted. Major intraoperative complications, including vascular injury, enterotomy, cystotomy, or conversion to laparotomy, were measured. Secondary outcomes including operative time, blood loss, transfusion rate, number of lymph nodes retrieved, and the length of hospitalization were also measured. Results 275 cases were identified–102 patients with robotic-assisted staging and 173 patients with traditional laparoscopic staging. There was no significant difference in the rate of major complications between groups (p=0.13). The mean operative time was longer in cases of robotic-assisted staging (237 min vs. 178 min, p<0.0001); however, blood loss was significantly lower (109 ml vs. 187 ml, p<0.0001). The mean number of lymph nodes retrieved were similar between groups (p=0.32). There were no significant differences in the time to discharge, re-admission, or re-operation rates between the two groups. Conclusion Robotic-assisted surgery is an acceptable alternative to laparoscopy for minimally invasive staging of endometrial cancer. In addition to the improved ease of operation, visualization, and range of motion of the robotic instruments, robotic surgery results in a lower mean blood loss, although longer operative time. More data are needed to determine if the rates of urinary tract injuries and other surgical complications can be reduced with the use of robotic surgery. PMID:20144471

Flare forecasting at the Met Office Space Weather Operations Centre

NASA Astrophysics Data System (ADS)

Murray, S. A.; Bingham, S.; Sharpe, M.; Jackson, D. R.

2017-04-01

The Met Office Space Weather Operations Centre produces 24/7/365 space weather guidance, alerts, and forecasts to a wide range of government and commercial end-users across the United Kingdom. Solar flare forecasts are one of its products, which are issued multiple times a day in two forms: forecasts for each active region on the solar disk over the next 24 h and full-disk forecasts for the next 4 days. Here the forecasting process is described in detail, as well as first verification of archived forecasts using methods commonly used in operational weather prediction. Real-time verification available for operational flare forecasting use is also described. The influence of human forecasters is highlighted, with human-edited forecasts outperforming original model results and forecasting skill decreasing over longer forecast lead times.

Robot-assisted approach improves surgical outcomes in obese patients undergoing partial nephrectomy.

PubMed

Malkoc, Ercan; Maurice, Matthew J; Kara, Onder; Ramirez, Daniel; Nelson, Ryan J; Caputo, Peter A; Mouracade, Pascal; Stein, Robert; Kaouk, Jihad H

2017-02-01

To assess the impact of approach on surgical outcomes in otherwise healthy obese patients undergoing partial nephrectomy for small renal masses. Using our institutional partial nephrectomy database, we abstracted data on otherwise healthy (Charlson comorbidity score ≤1 and bilateral kidneys), obese patients (body mass index >30 kg/m 2 ) with small renal masses (<4 cm) treated between 2011 and 2015. The primary outcomes were intra-operative transfusion, operating time, length of hospital stay (LOS), and postoperative complications. The association between approach, open (OPN) vs robot-assisted partial nephrectomy (RAPN), and outcomes was assessed by univariable and multivariable logistic regression analyses. Covariates included age, gender, obesity severity, tumour size and tumour complexity. Of 237 obese patients undergoing partial nephrectomy, 25% underwent OPN and 75% underwent RAPN. Apart from larger tumour size in the OPN group (2.8 vs 2.5 cm; P = 0.02), there was no significant difference between groups. The rate of intra-operative blood transfusion (1.1 vs 10%; P = 0.01), the median operating time (180 vs 207 min; P < 0.01) and the median ischaemia time (19.5 vs 27 min; P < 0.01) were all greater for OPN. The LOS was significantly shorter for RAPN (3 vs 4 days; P < 0.01). While the overall complication rate was higher for OPN (15.8 vs 31.7%; P < 0.01), major complications were not significantly different (5.6 vs 1.7%; P = 0.20). On multivariable analyses, OPN independently predicted longer operating time, longer length of stay, and more overall complications. At a high-volume centre, the robot-assisted approach offers less blood transfusion, shorter operating time, faster recovery, and fewer peri-operative complications compared with the open approach in obese patients undergoing partial nephrectomy for small renal masses. In this setting, RAPN may be a preferable treatment option. © 2016 The Authors BJU International © 2016 BJU International Published by John Wiley & Sons Ltd.

Prolonged Operative Duration Increases Risk of Surgical Site Infections: A Systematic Review

PubMed Central

Chen, Brian Po-Han; Soleas, Ireena M.; Ferko, Nicole C.; Cameron, Chris G.; Hinoul, Piet

2017-01-01

Abstract Background: The incidence of surgical site infection (SSI) across surgical procedures, specialties, and conditions is reported to vary from 0.1% to 50%. Operative duration is often cited as an independent and potentially modifiable risk factor for SSI. The objective of this systematic review was to provide an in-depth understanding of the relation between operating time and SSI. Patients and Methods: This review included 81 prospective and retrospective studies. Along with study design, likelihood of SSI, mean operative times, time thresholds, effect measures, confidence intervals, and p values were extracted. Three meta-analyses were conducted, whereby odds ratios were pooled by hourly operative time thresholds, increments of increasing operative time, and surgical specialty. Results: Pooled analyses demonstrated that the association between extended operative time and SSI typically remained statistically significant, with close to twice the likelihood of SSI observed across various time thresholds. The likelihood of SSI increased with increasing time increments; for example, a 13%, 17%, and 37% increased likelihood for every 15 min, 30 min, and 60 min of surgery, respectively. On average, across various procedures, the mean operative time was approximately 30 min longer in patients with SSIs compared with those patients without. Conclusions: Prolonged operative time can increase the risk of SSI. Given the importance of SSIs on patient outcomes and health care economics, hospitals should focus efforts to reduce operative time. PMID:28832271

An assessment of the quality indicators of operative and non-operative times in a public university hospital

PubMed Central

Costa, Altair da Silva; Leão, Luiz Eduardo Villaça; de Novais, Maykon Anderson Pires; Zucchi, Paola

2015-01-01

ABSTRACT Objective To assess the operative time indicators in a public university hospital. Methods A descriptive cross-sectional study was conducted using data from operating room database. The sample was obtained from January 2011 to January 2012. The operations performed in sequence in the same operating room, between 7:00 am and 5:00 pm, elective or emergency, were included. The procedures with incomplete data in the system were excluded, as well as the operations performed after 5:00 pm or on weekends or holidays. Results We measured the operative and non-operative time of 8,420 operations. The operative time (mean and standard deviation) of anesthesias and operations were 177.6±110 and 129.8±97.1 minutes, respectively. The total time of the patient in operative room (mean and standard deviation) was 196.8±113.2. The non-operative time, e.g., between the arrival of the patient and the onset of anesthesia was 14.3±17.3 minutes. The time to set the next patient in operating room was 119.8±79.6 minutes. Our total non-operative time was 155 minutes. Conclusion Delays frequently occurred in our operating room and had a major effect on patient flow and resource utilization. The non-operative time was longer than the operative time. It is possible to increase the operating room capacity by management and training of the professionals involved. The indicators provided a tool to improve operating room efficiency. PMID:26761557

Osmotic Acoustic Source

DTIC Science & Technology

2017-09-25

sonar range operations (for example, 15000 meters and longer). This means that the two-way travel time is typically at least twenty seconds...in the enclosure through osmosis. Valves open at a specified time after the liquid injection to free flood between the enclosure and the...the timing of the salt jets and the free-flooding valves enables a repeatable Attorney Docket No. 300070 4 of 14 acoustic pulse at low

The costs and quality of operative training for residents in tympanoplasty type I.

PubMed

Wang, Mao-Che; Yu, Eric Chen-Hua; Shiao, An-Suey; Liao, Wen-Huei; Liu, Chia-Yu

2009-05-01

A teaching hospital would incur more operation room costs on training surgical residents. To evaluate the increased operation time and the increased operation room costs of operations performed by surgical residents. As a model we used a very common surgical otology procedure -- tympanoplasty type I. From January 1, 2004 to December 31, 2004, we included in this study 100 patients who received tympanoplasty type I in Taipei Veterans General Hospital. Fifty-six procedures were performed by a single board-certified surgeon and 44 procedures were performed by residents. We analyzed the operation time and surgical outcomes in these two groups of patients. The operation room cost per minute was obtained by dividing the total operation room expenses by total operation time in the year 2004. The average operation time of residents was 116.47 min, which was significantly longer (p<0.0001) than that of the board-certified surgeon (average 81.07 min). It cost USD $40.36 more for each operation performed by residents in terms of operation room costs. The surgical success rate of residents was 81.82%, which was significantly lower (p=0.016) than that of the board-certified surgeon (96.43%).

Time scales of tunneling decay of a localized state

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

Ban, Yue; Muga, J. G.; Sherman, E. Ya.

2010-12-15

Motivated by recent time-domain experiments on ultrafast atom ionization, we analyze the transients and time scales that characterize, aside from the relatively long lifetime, the decay of a localized state by tunneling. While the tunneling starts immediately, some time is required for the outgoing flux to develop. This short-term behavior depends strongly on the initial state. For the initial state, tightly localized so that the initial transients are dominated by over-the-barrier motion, the time scale for flux propagation through the barrier is close to the Buettiker-Landauer traversal time. Then a quasistationary, slow-decay process follows, which sets ideal conditions for observingmore » diffraction in time at longer times and distances. To define operationally a tunneling time at the barrier edge, we extrapolate backward the propagation of the wave packet that escaped from the potential. This extrapolated time is considerably longer than the time scale of the flux and density buildup at the barrier edge.« less

Improvements in Operational Readiness by Distributing Manufacturing Capability in the Supply Chain through Additive Manufacturing

DTIC Science & Technology

2017-12-01

inefficiencies of a more complex system. Additional time may also be due to the longer distances traveled . The fulfillment time for a requisition to...Approved OMB No. 0704-0188 Public reporting burden for this collection of information is estimated to average 1 hour per response, including the time ...advanced manufacturing methods with additive manufacturing. This work decomposes the additive manufacturing processes into 11 primary functions. The time

Effects of NOX Storage Component on Ammonia Formation in TWC for Passive SCR NOX Control in Lean Gasoline Engines

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

Prikhodko, Vitaly Y.; Pihl, Josh A.; Toops, Todd J.

A prototype three-way catalyst (TWC) with NOX storage component was evaluated for ammonia (NH3) generation on a 2.0-liter BMW lean burn gasoline direct injection engine as a component in a passive ammonia selective catalytic reduction (SCR) system. The passive NH3 SCR system is a potential approach for controlling nitrogen oxides (NOX) emissions from lean burn gasoline engines. In this system, NH3 is generated over a close-coupled TWC during periodic slightly-rich engine operation and subsequently stored on an underfloor SCR catalyst. Upon switching to lean, NOX passes through the TWC and is reduced by the stored NH3 on the SCR catalyst.more » Adding a NOX storage component to a TWC provides two benefits in the context of a passive SCR system: (1) enabling longer lean operation by storing NOX upstream and preserving NH3 inventory on the downstream SCR catalyst; and (2) increasing the quantity and rate of NH3 production during rich operation. Since the fuel penalty associated with passive SCR NOX control depends on the fraction of time that the engine is running rich rather than lean, both benefits (longer lean times and shorter rich times achieved via improved NH3 production) will decrease the passive SCR fuel penalty. However, these benefits are primarily realized at low to moderate temperatures (300-500 °C), where the NOX storage component is able to store NOX, with little to no benefit at higher temperatures (>500 °C), where NOX storage is no longer effective. This study discusses engine parameters and control strategies affecting the NH3 generation over a TWC with NOX storage component.« less

Managing Science Operations during Planetary Surface Operations at Long Light Delay-Time Targets: The 2011 Desert RATS Test

NASA Technical Reports Server (NTRS)

Eppler, D. B.

2012-01-01

Desert Research and Technology Studies (Desert RATS) is a multi-year series of hardware and operations tests carried out annually in the high desert of Arizona in the San Francisco Volcanic Field. Conducted since 1997, these activities are designed to exercise planetary surface hardware and operations in conditions where multi-day tests are achievable. Desert RATS 2011 Science Operations Test simulated the management of crewed science operations at targets that were beyond the light delay time experienced during Low-Earth Orbit (LEO) and lunar surface missions, such as a mission to a Near-Earth Object (NEO) or the martian surface. Operations at targets at these distances are likely to be the norm as humans move out of the Earth-Moon system. Operating at these distances places significant challenges on mission operations, as the imposed light-delay time makes normal, two-way conversations extremely inefficient. Consequently, the operations approach for space missions that has been exercised during the first half-century of human space operations is no longer viable, and new approaches must be devised.

Preoperative fasting times in elective surgical patients at a referral Hospital in Botswana

PubMed Central

Abebe, Worknehe Agegnehu; Rukewe, Ambrose; Bekele, Negussie Alula; Stoffel, Moeng; Dichabeng, Mompelegi Nicoh; Shifa, Jemal Zeberga

2016-01-01

Introduction Adults and children are required to fast before anaesthesia to reduce the risk of regurgitation and aspiration of gastric contents. However, prolonged periods of fasting are unnecessary and may cause complications. This study was conducted to evaluate preoperative fasting period in our centre and compare it with the ASA recommendations and factors that influence fasting periods. Methods This is a cross-sectional study of preoperative fasting times among elective surgical patients. A total numbers of 260 patients were interviewed as they arrived at the reception area of operating theatre using questionnaire. Results Majority of patients (98.1%) were instructed to fast from midnight. Fifteen patients (5.8%) reported that they were told the importance of preoperative fasting. The mean fasting period were 15.9±2.5 h (range 12.0-25.3 h) for solids and 15.3±2.3 h (range 12.0-22.0 h) for liquids. The mean duration of fasting was significantly longer for patients operated after midday compared to those operated before midday, p<0.001. Conclusion The mean fasting periods were 7.65 times longer for clear liquid and 2.5 times for solids than the ASA guidelines. It is imperative that the Hospital should establish Preoperative fasting policies and teach the staff who should ensure compliance with guidelines. PMID:27222691

The Flipped Classroom of Operations Management: A Not-for-Cost-Reduction Platform

ERIC Educational Resources Information Center

Asef-Vaziri, A.

2015-01-01

By delivering lectures online using screen capture technology, students can learn course material at the time and location of their choice, when they are in control to pause, rewind, and fast forward the professor. Class time is no longer spent teaching basic concepts, but rather focused on more value-added activities such as problem solving,…

Time to adjust to changes in ventilation settings varies significantly between different T-piece resuscitators, self-inflating bags, and manometer equipped self-inflating bags.

PubMed

Hartung, Julia C; Dold, Simone K; Thio, Marta; tePas, Arjan; Schmalisch, Gerd; Roehr, Charles Christoph

2014-06-01

Resuscitation guidelines give no preference over use of self-inflating bags (SIBs) or T-piece resuscitators (TPR) for manual neonatal ventilation. We speculated that devices would differ significantly regarding time required to adjust to changed ventilation settings. This was a laboratory study. Time to adjust from baseline peak inflation pressure (PIP) (20 cmH2O) to target PIP (25 and 40 cmH2O), ability to adhere to predefined ventilation settings (PIP, PEEP, and inflation rate [IR]), and the variability within and between operators were assessed for a SIB without manometer, SIB with manometer (SIBM), and two TPRs. Adjustment time was significantly longer with TPRs, compared with SIB and SIBM. The SIBM and TPRs were < 5% (median) off target PIP, and the SIB was 14% off target PIP. Significant variability between operators (interquartile range [IQR]: 71%) was seen with SIBs. PIP adjustment takes longer with TPRs, compared with SIB/SIBM. TPRs and SIBM allow satisfactory adherence to ventilation parameters. SIBs should only be used with manometer attached. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

40 CFR 60.285a - Test methods and procedures.

Code of Federal Regulations, 2014 CFR

2014-07-01

... performance test. (b) The owner or operator must determine compliance with the filterable particulate matter... used to determine the filterable particulate matter concentration. The sampling time and sample volume... repeat performance tests for filterable particulate matter at intervals no longer than 5 years following...

Minimally invasive surgery for endometrial cancer: does operative start time impact surgical and oncologic outcomes?

PubMed

Slaughter, Katrina N; Frumovitz, Michael; Schmeler, Kathleen M; Nick, Alpa M; Fleming, Nicole D; dos Reis, Ricardo; Munsell, Mark F; Westin, Shannon N; Soliman, Pamela T; Ramirez, Pedro T

2014-08-01

Recent literature in ovarian cancer suggests differences in surgical outcomes depending on operative start time. We sought to examine the effects of operative start time on surgical outcomes for patients undergoing minimally invasive surgery for endometrial cancer. A retrospective review was conducted of patients undergoing minimally invasive surgery for endometrial cancer at a single institution between 2000 and 2011. Surgical and oncologic outcomes were compared between patients with an operative start time before noon and those with a surgical start time after noon. A total of 380 patients were included in the study (245 with start times before noon and 135 with start times after noon). There was no difference in age (p=0.57), number of prior surgeries (p=0.28), medical comorbidities (p=0.19), or surgical complexity of the case (p=0.43). Patients with surgery starting before noon had lower median BMI than those beginning after noon, 31.2 vs. 35.3 respectively (p=0.01). No significant differences were observed for intraoperative complications (4.4% of patients after noon vs. 3.7% of patients before noon, p=0.79), estimated blood loss (median 100 cc vs. 100 cc, p=0.75), blood transfusion rates (7.4% vs. 8.2%, p=0.85), and conversion to laparotomy (12.6% vs. 7.4%, p=0.10). There was no difference in operative times between the two groups (198 min vs. 216.5 min, p=0.10). There was no association between operative start time and postoperative non-infectious complications (11.9% vs. 11.0%, p=0.87), or postoperative infections (17.8% vs. 12.3%, p=0.78). Length of hospital stay was longer for surgeries starting after noon (median 2 days vs. 1 day, p=0.005). No differences were observed in rates of cancer recurrence (12.6% vs. 8.8%, p=0.39), recurrence-free survival (p=0.97), or overall survival (p=0.94). Our results indicate equivalent surgical outcomes and no increased risk of postoperative complications regardless of operative start time in minimally invasive endometrial cancer staging, despite longer length of hospital stay for surgeries beginning after noon. Copyright © 2014 Elsevier Inc. All rights reserved.

A novel dual motor drive system for three wheel electric vehicles

NASA Astrophysics Data System (ADS)

Panmuang, Piyapat; Thongsan, Taweesak; Suwapaet, Nuchida; Laohavanich, Juckamass; Photong, Chonlatee

2018-03-01

This paper presents a novel dual motor drive system used for three wheel electric vehicles that have one free wheel at the front and two wheels with a drive system at the end of the vehicles. A novel dual motor drive system consists of two identical DC motors that are independently controlled by its speed-torque controller. Under light load conditions, only one of the DC motors will operate around it rated whilst under hard load conditions both of the DC motors will operate. With this drive system, the motors will operate only at its high performance at rated or else no operate to retain longer lifetime. The simulated results for the Skylab three wheel electric vehicle prototype with 8kW at full load (high torque, low speed) and around 4kW at light/normal operating loads (regular speed-torque) showed that the proposed system provides better dynamic responses with faster overshoot current/voltage recovery time, has lower investment costs, has longer lifetime of the motors and allows the motors to always operate at their high performance and thus achieve more cost effective system compared to a single motor drive system with 8kW DC motors.

Robotic Versus Laparoscopic Colorectal Cancer Surgery in Elderly Patients: A Propensity Score Match Analysis.

PubMed

de'Angelis, Nicola; Abdalla, Solafah; Bianchi, Giorgio; Memeo, Riccardo; Charpy, Cecile; Petrucciani, Niccolo; Sobhani, Iradj; Brunetti, Francesco

2018-05-31

Minimally invasive surgery in elderly patients with colorectal cancer remains controversial. The study aimed to compare the operative, postoperative, and oncologic outcomes of robotic (robotic colorectal resection surgery [RCRS]) versus laparoscopic colorectal resection surgery (LCRS) in elderly patients with colorectal cancer. Propensity score matching (PSM) was used to compare patients aged 70 years and more undergoing elective RCRS or LCRS for colorectal cancer between 2010 and 2017. Overall, 160 patients underwent elective curative LCRS (n = 102) or RCRS (n = 58) for colorectal cancer. Before PSM, the mean preoperative Charlson score and the tumor size were significantly lower in the robotic group. After matching, 43 RCRSs were compared with 43 LCRSs. The RCRS group showed longer operative times (300.6 versus 214.5 min, P = .03) compared with LCRS, but all other operative variables were comparable between the two groups. No differences were found for postoperative morbidity, mortality, time to flatus, return to regular diet, and length of hospital stay. R0 resection was obtained in 95.3% of procedures. The overall and disease-free survival rates at 1, 2, and 3 years were similar between RCRS and LCRS patients. The presence of more than one comorbidity before surgery was significantly associated with the incidence of postoperative complications. In patients aged 70 years or more, robotic colorectal surgery showed operative and oncologic outcomes similar to those obtained by laparoscopy, despite longer operative times. Randomized trials are awaited to reliably assess the clinical and oncological noninferiority and the costs/benefits ratio of robotic colorectal surgery in elderly populations.

Effect of socioeconomic deprivation on waiting time for cardiac surgery: retrospective cohort study

PubMed Central

Pell, Jill P; Pell, Alastair C H; Norrie, John; Ford, Ian; Cobbe, Stuart M

2000-01-01

Objective To determine whether the priority given to patients referred for cardiac surgery is associated with socioeconomic status. Design Retrospective study with multivariate logistic regression analysis of the association between deprivation and classification of urgency with allowance for age, sex, and type of operation. Multivariate linear regression analysis was used to determine association between deprivation and waiting time within each category of urgency, with allowance for age, sex, and type of operation. Setting NHS waiting lists in Scotland. Participants 26 642 patients waiting for cardiac surgery, 1 January 1986 to 31 December 1997. Main outcome measures Deprivation as measured by Carstairs deprivation category. Time spent on NHS waiting list. Results Patients who were most deprived tended to be younger and were more likely to be female. Patients in deprivation categories 6 and 7 (most deprived) waited about three weeks longer for surgery than those in category 1 (mean difference 24 days, 95% confidence interval 15 to 32). Deprived patients had an odds ratio of 0.5 (0.46 to 0.61) for having their operations classified as urgent compared with the least deprived, after allowance for age, sex, and type of operation. When urgent and routine cases were considered separately, there was no significant difference in waiting times between the most and least deprived categories. Conclusions Socioeconomically deprived patients are thought to be more likely to develop coronary heart disease but are less likely to be investigated and offered surgery once it has developed. Such patients may be further disadvantaged by having to wait longer for surgery because of being given lower priority. PMID:10617517

Dysphagia in infants after open heart procedures.

PubMed

Yi, Sook-Hee; Kim, Sang-Jun; Huh, June; Jun, Tae-Gook; Cheon, Hee Jung; Kwon, Jeong-Yi

2013-06-01

The aims of this study were to evaluate the prevalence and the clinical predictors of dysphagia and to determine the characteristics of videofluoroscopic swallowing study findings in infants after open heart procedures. This study is a retrospective review of 146 infants who underwent open heart surgery. The infants with dysphagia were compared with those without dysphagia. The videofluoroscopic swallowing study findings of the infants with dysphagia were also evaluated. Of the 146 infants who underwent open heart surgery, 35 (24.0%) had dysphagia symptoms. The infants with dysphagia had lower body weight at operation, more malformation syndromes, longer operation times, and more complex operations than did the infants without dysphagia. In addition, the infants with dysphagia required more time to achieve full oral feeding and had longer hospital stays. Thirty-three infants underwent videofluoroscopic swallowing study: 32 (97.0%) exhibited at least one abnormal finding among the videofluoroscopic swallowing study parameters and 21 (63.6%) exhibited tracheal aspiration. Given the high rate of aspiration in the infants who underwent open heart procedures, monitoring and prompt recognition of the signs and the risk factors of dysphagia may substantially improve infant care with oral feeding and reduce the duration of hospital stays.

Observing strategies for future solar facilities: the ATST test case

NASA Astrophysics Data System (ADS)

Uitenbroek, H.; Tritschler, A.

2012-12-01

Traditionally solar observations have been scheduled and performed very differently from night time efforts, in particular because we have been observing the Sun for a long time, requiring new combinations of observables to make progress, and because solar physics observations are often event driven on time scales of hours to days. With the proposal pressure that is expected for new large-aperture facilities, we can no longer afford the time spent on custom setups, and will have to rethink our scheduling and operations. We will discuss our efforts at Sac Peak in preparing for this new era, and outline the planned scheduling and operations planning for the ATST in particular.

Waiting for cataract surgery--effects of a maximum waiting-time guarantee.

PubMed

Hanning, Marianne; Lundström, Mats

2007-01-01

To evaluate the effects of the Maximum Waiting-time Guarantee (MWG) policy for cataract surgery on volume, indications, waiting times and priority setting in Sweden. Comparison between 1993 and 1994, when the guarantee had been in force for one year, and 1998 and 1999, when the policy had been terminated for one year. Data from the National Cataract Registry covering 156,657 cataract operations for the years studied. The number of operations increased by 43% between the two study periods. Of this increase, 61% were patients with a visual acuity above 0.5 in the better eye, i.e. low-priority patients. Waiting times were longer for all patient categories in the later period and differences in waiting times between patients with differing priority diminished. Variations among the units in priority setting and waiting times were substantial, and increased after the Guarantee was terminated. The Guarantee with its explicit indications was an effective policy instrument to limit waiting times and improve access for patients with the greatest need. It is unlikely that the Guarantee caused any 'crowding out' of other patient groups. When the Guarantee was not in force, indications for surgery widened. This, however, resulted in longer waiting times for all patient groups. After the Guarantee was terminated, the already substantial differences in access and indications among ophthalmic units became even greater.

PTTI applications at the limits of GPS

NASA Technical Reports Server (NTRS)

Douglas, Rob J.; Popelar, J.

1995-01-01

Canadian plans for precise time and time interval services are examined in the light of GPS capabilities developed for geodesy. We present our experience in establishing and operating a geodetic type GPS station in a time laboratory setting, and show sub-nanosecond residuals for time transfer between geodetic sites. We present our approach to establishing realistic standard uncertainties for short-term frequency calibration services over time intervals of hours, and for longer-term frequency dissemination at better than the 10(exp -15) level of accuracy.

Evaluation of Digital Checklists for Command and Control Operations

DTIC Science & Technology

2016-01-01

EVALUATION OF DIGITAL CHECKLISTS FOR COMMAND AND CONTROL OPERATIONS Christopher K. McClernon 1 , Victor S. Finomore 2 , Terence S. Andre 3...the potential effectiveness of a digital system that could take the place of the paper system that is currently being used. A between groups...assessments of each system were analyzed and compared. The data showed that a linear digital checklist takes a longer amount of time than both a paper

Increased mean time from end of surgery to operating room exit in a historical cohort of cases with prolonged time to extubation.

PubMed

Dexter, Franklin; Epstein, Richard H

2013-12-01

Prolonged time to extubation has been defined as the occurrence of a ≥ 15-minute interval from the end of surgery to removal of the tracheal tube. We quantified the increases in the mean times from end of surgery to exit from the OR associated with prolonged extubations and tested whether the increases were economically important (≥ 5 minutes). Anesthesia information management system data from 1 tertiary hospital were collected from November 2005 through December 2012 (i.e., sample sizes were N = 22 sequential quarters). Cases were excluded in which the patient's trachea was not intubated or extubated while physically in the operating room (OR). For each combination of stratification variable (below) and quarter, the mean time from end of surgery to OR exit was calculated for the extubations that were not prolonged and for those that were prolonged. Results are reported as mean ± SEM, with "at least" denoting the lower 95% confidence interval. The mean times from end of surgery to OR exit were at least 12.6 minutes longer for prolonged extubations when calculated with stratification by duration of surgery and prone or other positioning (13.0 ± 0.1 minutes), P < 0.0001 compared to 5 minutes (i.e., times were substantively long economically). The mean times were at least 11.7 minutes longer when calculated stratified by anesthesia procedure code (12.4 ± 0.4, P < 0.0001) and at least 11.3 minutes longer when calculated stratified by surgeon (12.4 ± 0.6, P < 0.0001). We recommend that anesthesia providers document the times of extubations and monitor the incidence of prolonged extubations as an economic measure. This would be especially important for providers at facilities with many ORs that have at least 8 hours of cases and turnovers.

Code Help: Can This Unique State Regulatory Intervention Improve Emergency Department Crowding?

PubMed

Michael, Sean S; Broach, John P; Kotkowski, Kevin A; Brush, D Eric; Volturo, Gregory A; Reznek, Martin A

2018-05-01

Emergency department (ED) crowding adversely affects multiple facets of high-quality care. The Commonwealth of Massachusetts mandates specific, hospital action plans to reduce ED boarding via a mechanism termed "Code Help." Because implementation appears inconsistent even when hospital conditions should have triggered its activation, we hypothesized that compliance with the Code Help policy would be associated with reduction in ED boarding time and total ED length of stay (LOS) for admitted patients, compared to patients seen when the Code Help policy was not followed. This was a retrospective analysis of data collected from electronic, patient-care, timestamp events and from a prospective Code Help registry for consecutive adult patients admitted from the ED at a single academic center during a 15-month period. For each patient, we determined whether the concurrent hospital status complied with the Code Help policy or violated it at the time of admission decision. We then compared ED boarding time and overall ED LOS for patients cared for during periods of Code Help policy compliance and during periods of Code Help policy violation, both with reference to patients cared for during normal operations. Of 89,587 adult patients who presented to the ED during the study period, 24,017 (26.8%) were admitted to an acute care or critical care bed. Boarding time ranged from zero to 67 hours 30 minutes (median 4 hours 31 minutes). Total ED LOS for admitted patients ranged from 11 minutes to 85 hours 25 minutes (median nine hours). Patients admitted during periods of Code Help policy violation experienced significantly longer boarding times (median 20 minutes longer) and total ED LOS (median 46 minutes longer), compared to patients admitted under normal operations. However, patients admitted during Code Help policy compliance did not experience a significant increase in either metric, compared to normal operations. In this single-center experience, implementation of the Massachusetts Code Help regulation was associated with reduced ED boarding time and ED LOS when the policy was consistently followed, but there were adverse effects on both metrics during violations of the policy.

DSN Resource Scheduling

NASA Technical Reports Server (NTRS)

Wang, Yeou-Fang; Baldwin, John

2007-01-01

TIGRAS is client-side software, which provides tracking-station equipment planning, allocation, and scheduling services to the DSMS (Deep Space Mission System). TIGRAS provides functions for schedulers to coordinate the DSN (Deep Space Network) antenna usage time and to resolve the resource usage conflicts among tracking passes, antenna calibrations, maintenance, and system testing activities. TIGRAS provides a fully integrated multi-pane graphical user interface for all scheduling operations. This is a great improvement over the legacy VAX VMS command line user interface. TIGRAS has the capability to handle all DSN resource scheduling aspects from long-range to real time. TIGRAS assists NASA mission operations for DSN tracking of station equipment resource request processes from long-range load forecasts (ten years or longer), to midrange, short-range, and real-time (less than one week) emergency tracking plan changes. TIGRAS can be operated by NASA mission operations worldwide to make schedule requests for the DSN station equipment.

Management accounting for advanced technological environments.

PubMed

Kaplan, R S

1989-08-25

Management accounting systems designed decades ago no longer provide timely, relevant information for companies in today's highly competitive environment. New operational control and performance measurement systems are recognizing the importance of direct measurement of quality, manufacturing lead times, flexibility, and customer responsiveness, as well as more accurate measures of the actual costs of consumed resources. Activity-based cost systems can assign the costs of indirect and support resources to the specific products and activities that benefit from these resources. Both operational control and activity-based systems represent new opportunities for improved managerial information in complex, technologically advanced environments.

Managing Relations with Industry: The Case of Brazilian Universities

ERIC Educational Resources Information Center

Lahorgue, Maria Alice

2005-01-01

For a long time, university-business relations were a matter of individual, informal and intermittent contacts. Once the innovation process picked up speed, businesses began asking more from universities (longer-term co-operative research, for example), and governments placed university-business interaction at the centre of their innovation…

Identification of g-Modes in a Sun with Mixed Core

NASA Technical Reports Server (NTRS)

Wolff, Charles L.

2008-01-01

The elusive g-mode oscillations mainly operate deep inside the Sun where the nuclear fires burn. They can modify the Sun's output on a cadence of months and years when coupled into groups. Scientists have failed to detect their oscillation periods because they were looking for periods much too short. This paper shows that if g-modes slowly mix the central 16% of the Sun on a million year time scale or less, then g-mode periods become two and a half times longer. These longer periods are identified in existing data from the orbiting GOLF and SOH0 experiments. This opens the door to measuring the Sun's central regions with g-modes just as helioseismology has used sound waves to probe its outer half.

Long Term Outcomes of Laparoscopic and Open Modified Lich-Gregoir Reimplantation in Adults: A multicentric comparative study.

PubMed

Atar, Arda; Eksi, Mithat; Güler, Ahmet Faysal; Tuncer, Murat; Akkas, Fatih; Tugcu, Volkan

2017-01-01

Obstructive ureteral pathologies in adult patients are most commonly due to ureteral strictures and secondary to surgical interventions. In this study, we aimed to compare open and laparoscopic modified Lich-Gregoir ureteral reimplantation with regards to outcomes in benign ureteral pathologies in adult patients. Between December 2008 and December 2014, 32 open cases and 29 laparoscopic cases were performed as per the data retrieved from surgical databases. All laparoscopic procedures were performed in Bakirkoy Dr. Sadi Konuk Training and Research Hospital(BEAH) and all open ureteral reimplantation procedures in Kartal Dr Lutfi Kirdar Training and Research Hospital(KEAH) and Okmeydani Training and Research Hospital(OEAH). The mean operation time was significantly lower in the group of patients operated with open group (142.5 minutes versus 188.9 minutes; P< 0.0001). The mean duration of follow-up was longer in the laparoscopy group (31 versus 28 months; p< 0.0001). The mean amount of operation associated blood loss was significantly lower in patients operated laparoscopically (93.7 mL versus 214 mL; P< 0.0001). The mean VAS score obtained six hours after surgery was 6.6 ± 0.8 in open group, and 5.8 ± 0.7 in laparoscopic group (p=0.0004). The mean VAS scores measured at post-operative day 1 was 4.5 ± 0.7 in open group and 3.7 ± 0.9 in laparoscopy group. Time required to achieve the pre-operative capability of daily activities was significantly longer in open group (15 ± 1.4 days vs 11 ± 1.4 days; p< 0.0001). Despite open techniques provide shorter operation time and laparoscopic techniques require long learning curve, we think that laparoscopic techniques are superior to open ones since that they provide a better post-operative comfort and are better tolerated in terms of complications.

Long Term Outcomes of Laparoscopic and Open Modified Lich-Gregoir Reimplantation in Adults: A multicentric comparative study

PubMed Central

Atar, Arda; Eksi, Mithat; Güler, Ahmet Faysal; Tuncer, Murat; Akkas, Fatih; Tugcu, Volkan

2017-01-01

Background & Objective: Obstructive ureteral pathologies in adult patients are most commonly due to ureteral strictures and secondary to surgical interventions. In this study, we aimed to compare open and laparoscopic modified Lich-Gregoir ureteral reimplantation with regards to outcomes in benign ureteral pathologies in adult patients. Methods: Between December 2008 and December 2014, 32 open cases and 29 laparoscopic cases were performed as per the data retrieved from surgical databases. All laparoscopic procedures were performed in Bakirkoy Dr. Sadi Konuk Training and Research Hospital(BEAH) and all open ureteral reimplantation procedures in Kartal Dr Lutfi Kirdar Training and Research Hospital(KEAH) and Okmeydani Training and Research Hospital(OEAH). Results: The mean operation time was significantly lower in the group of patients operated with open group (142.5 minutes versus 188.9 minutes; P< 0.0001). The mean duration of follow-up was longer in the laparoscopy group (31 versus 28 months; p< 0.0001). The mean amount of operation associated blood loss was significantly lower in patients operated laparoscopically (93.7 mL versus 214 mL; P< 0.0001). The mean VAS score obtained six hours after surgery was 6.6 ± 0.8 in open group, and 5.8 ± 0.7 in laparoscopic group (p=0.0004). The mean VAS scores measured at post-operative day 1 was 4.5 ± 0.7 in open group and 3.7 ± 0.9 in laparoscopy group. Time required to achieve the pre-operative capability of daily activities was significantly longer in open group (15 ± 1.4 days vs 11 ± 1.4 days; p< 0.0001). Conclusion: Despite open techniques provide shorter operation time and laparoscopic techniques require long learning curve, we think that laparoscopic techniques are superior to open ones since that they provide a better post-operative comfort and are better tolerated in terms of complications. PMID:29067040

Urethroplasty for treatment of long anterior urethral stricture: buccal mucosa graft versus penile skin graft-does the stricture length matter?

PubMed

Hussein, Mohamed M; Almogazy, Hazem; Mamdouh, Ahmed; Farag, Fawzy; Rashed, Elnesr; Gamal, Wael; Rashed, Ahmed; Zaki, Mohamed; Salem, Esam; Ryad, Ahmed

2016-11-01

To investigate the surgical outcomes of dorsal onlay urethroplasty (DOU) using buccal mucosa graft (BMG) or penile skin graft (PSG) and to assess the effect of stricture length in men with anterior urethral strictures. A prospective cohort included men with anterior urethral strictures between 2008 and 2015. Patients underwent DOU using PSG or BMG. Patients had urethrography and uroflowmetry at 0, 3, 6, 12 months, and urethroscopy when needed. Student's t test, Mann-Whitney U tests, and Pearson's Chi-square test were used for analysis. Sixty-nine patients (43 ± 14 year) were included, 31 received BMG, and 38 received PSG. Mean stricture length was 8 ± 3 cm, mean operative time was 145 ± 31 min, and mean follow-up was 56 ± 10 mo. Success rate was 87 % (90 % BMG vs. 84 % PSG, p = 0.4). Mean operative time was significantly shorter in PSG group (136 ± 29 min vs. 256 ± 58 min, p = 0.0005). Complications of grade I developed in 36 % (wound infection = 10 %, postvoiding dribbling = 18.8 %). Thirty of 69 patients (43 %) had strictures ≥8 cm, and 39 (57 %) had strictures <8 cm-success rate was equal for both subgroups (87 %). Mean blood loss, mean operative time, and incidence of postvoid dribbling were significantly lower in strictures <8 cm. BMG and PSG have comparable success rates in treatment of long anterior urethral strictures. Operative time is significantly longer in BMG. Long-segment strictures are associated with longer operative time, more blood loss, and more occurrence of postvoid dribbling. However, the length of the stricture has no influence on the success rate and functional outcomes of DOU.

Modelling the time at which overcrowding and feed interruption emerge on the swine premises under movement restrictions during a classical swine fever outbreak.

PubMed

Weng, H Y; Yadav, S; Olynk Widmar, N J; Croney, C; Ash, M; Cooper, M

2017-03-01

A stochastic risk model was developed to estimate the time elapsed before overcrowding (TOC) or feed interruption (TFI) emerged on the swine premises under movement restrictions during a classical swine fever (CSF) outbreak in Indiana, USA. Nursery (19 to 65 days of age) and grow-to-finish (40 to 165 days of age) pork production operations were modelled separately. Overcrowding was defined as the total weight of pigs on premises exceeding 100% to 115% of the maximum capacity of the premises, which was computed as the total weight of the pigs at harvest/transition age. Algorithms were developed to estimate age-specific weight of the pigs on premises and to compare the daily total weight of the pigs with the threshold weight defining overcrowding to flag the time when the total weight exceeded the threshold (i.e. when overcrowding occurred). To estimate TFI, an algorithm was constructed to model a swine producer's decision to discontinue feed supply by incorporating the assumptions that a longer estimated epidemic duration, a longer time interval between the age of pigs at the onset of the outbreak and the harvest/transition age, or a longer progression of an ongoing outbreak would increase the probability of a producer's decision to discontinue the feed supply. Adverse animal welfare conditions were modelled to emerge shortly after an interruption of feed supply. Simulations were run with 100 000 iterations each for a 365-day period. Overcrowding occurred in all simulated iterations, and feed interruption occurred in 30% of the iterations. The median (5th and 95th percentiles) TOC was 24 days (10, 43) in nursery operations and 78 days (26, 134) in grow-to-finish operations. Most feed interruptions, if they emerged, occurred within 15 days of an outbreak. The median (5th and 95th percentiles) time at which either overcrowding or feed interruption emerged was 19 days (4, 42) in nursery and 57 days (4, 130) in grow-to-finish operations. The study findings suggest that overcrowding and feed interruption could emerge early during a CSF outbreak among swine premises under movement restrictions. The outputs derived from the risk model could be used to estimate and evaluate associated mitigation strategies for alleviating adverse animal welfare conditions resulting from movement restrictions.

Stable and verifiable state estimation methods and systems with spacecraft applications

NASA Technical Reports Server (NTRS)

Li, Rongsheng (Inventor); Wu, Yeong-Wei Andy (Inventor)

2001-01-01

The stability of a recursive estimator process (e.g., a Kalman filter is assured for long time periods by periodically resetting an error covariance P(t.sub.n) of the system to a predetermined reset value P.sub.r. The recursive process is thus repetitively forced to start from a selected covariance and continue for a time period that is short compared to the system's total operational time period. The time period in which the process must maintain its numerical stability is significantly reduced as is the demand on the system's numerical stability. The process stability for an extended operational time period T.sub.o is verified by performing the resetting step at the end of at least one reset time period T.sub.r whose duration is less than the operational time period T.sub.o and then confirming stability of the process over the reset time period T.sub.r. Because the recursive process starts from a selected covariance at the beginning of each reset time period T.sub.r, confirming stability of the process over at least one reset time period substantially confirms stability over the longer operational time period T.sub.o.

Anterolateral minithoracotomy versus median sternotomy for mitral valve disease: a meta-analysis.

PubMed

Ding, Chao; Jiang, Da-ming; Tao, Kai-yu; Duan, Qun-jun; Li, Jie; Kong, Min-jian; Shen, Zhong-hua; Dong, Ai-qiang

2014-06-01

Mitral valve disease tends to be treated with anterolateral minithoracotomy (ALMT) rather than median sternotomy (MS), as ALMT uses progressively smaller incisions to promote better cosmetic outcomes. This meta-analysis quantifies the effects of ALMT on surgical parameters and post-operative outcomes compared with MS. One randomized controlled study and four case-control studies, published in English from January 1996 to January 2013, were identified and evaluated. ALMT showed a significantly longer cardiopulmonary bypass time (P=0.001) and aortic cross-clamp time (P=0.05) compared with MS. However, the benefits of ALMT were evident as demonstrated by a shorter length of hospital stay (P<0.00001). According to operative complications, the onset of new arrhythmias following ALMT decreased significantly as compared with MS (P=0.05); however, the incidence of peri-operative mortality (P=0.62), re-operation for bleeding (P=0.37), neurologic events (P=0.77), myocardial infarction (P=0.84), gastrointestinal complications (P=0.89), and renal insufficiency (P=0.67) were similar to these of MS. Long-term follow-up data were also examined, and revealed equivalent survival and freedom from mitral valve events. Current clinical data suggest that ALMT is a safe and effective alternative to the conventional approach and is associated with better short-term outcomes and a trend towards longer survival.

Anterolateral minithoracotomy versus median sternotomy for mitral valve disease: a meta-analysis

PubMed Central

Ding, Chao; Jiang, Da-ming; Tao, Kai-yu; Duan, Qun-jun; Li, Jie; Kong, Min-jian; Shen, Zhong-hua; Dong, Ai-qiang

2014-01-01

Objective: Mitral valve disease tends to be treated with anterolateral minithoracotomy (ALMT) rather than median sternotomy (MS), as ALMT uses progressively smaller incisions to promote better cosmetic outcomes. This meta-analysis quantifies the effects of ALMT on surgical parameters and post-operative outcomes compared with MS. Methods: One randomized controlled study and four case-control studies, published in English from January 1996 to January 2013, were identified and evaluated. Results: ALMT showed a significantly longer cardiopulmonary bypass time (P=0.001) and aortic cross-clamp time (P=0.05) compared with MS. However, the benefits of ALMT were evident as demonstrated by a shorter length of hospital stay (P<0.00001). According to operative complications, the onset of new arrhythmias following ALMT decreased significantly as compared with MS (P=0.05); however, the incidence of peri-operative mortality (P=0.62), re-operation for bleeding (P=0.37), neurologic events (P=0.77), myocardial infarction (P=0.84), gastrointestinal complications (P=0.89), and renal insufficiency (P=0.67) were similar to these of MS. Long-term follow-up data were also examined, and revealed equivalent survival and freedom from mitral valve events. Conclusions: Current clinical data suggest that ALMT is a safe and effective alternative to the conventional approach and is associated with better short-term outcomes and a trend towards longer survival. PMID:24903989

Reappraising the surgical approach on the perforated gastroduodenal ulcer: should gastric resection be abandoned?

PubMed

Kuwabara, Kazuaki; Matsuda, Shinya; Fushimi, Kiyohide; Ishikawa, Koichi B; Horiguchi, Hiromasa; Fujimori, Kenji

2011-10-01

Advancements in medical care for peptic ulcer disease (PUD) have reduced the need for invasive surgical procedures such as gastric resection (GR). Community-based PUD studies from a large sampling of PUD patients designed to analyze hospital resource use and outcomes after different surgical procedures have been rare. We aimed to exhaustively reappraise the risk factors and patient demographics that affect PUD patient recoveries after GR compared to those after simple closure (SC). We used a Japanese administrative database for 6 consecutive months each year between 2006 and 2010. The database included a total of 68,432 PUD patients; we analyzed 6,334 perforation cases and 3,148 cases of patients who underwent GR or SC. Study variables were demographics, comorbidities, characteristics of PUD, and operative day. Study outcomes that were analyzed included mortality, postoperative complications, ventilation administration, postoperative blood transfusions, length of stay, total charges, operating room (OR) time, and the postoperative fasting period (defined as the day of surgery to the day oral food intake was resumed.) To reduce selection bias in study procedures and to control the variation in hospital practice, a propensity score (PS) matching cohort analysis and a mixed linear regression model were used to assess the effects of GR on the outcomes. In 699 hospitals, 322 GRs and 2,826 SCs were observed. Younger age, duodenal ulcers, preexisting anemia and an operative day no more than 24hours were significant associated with the choice of SCs. No significant differences were observed in study outcomes after either GR or SC; more postoperative blood transfusions and longer OR times but shorter postoperative fasting periods were observed after GR. Longer OR times, ventilation and postoperative blood transfusion were significantly associated with mortality. Not GR but longer OR times use of ventilation and complications were the most significant indicators of increased resource use. There were no major significant differences in GR when compared to SC with regards to patient recoveries. Surgeons should obtain the skills and establish strategies to optimize either type of surgical procedure including minimizing OR time and establishing the best perioperative critical care. Peptic ulcer perforation; Simple closure; Gastric resection; Outcome; Resource use.

Transient-Switch-Signal Suppressor

NASA Technical Reports Server (NTRS)

Bozeman, Richard J., Jr.

1995-01-01

Circuit delays transmission of switch-opening or switch-closing signal until after preset suppression time. Used to prevent transmission of undesired momentary switch signal. Basic mode of operation simple. Beginning of switch signal initiates timing sequence. If switch signal persists after preset suppression time, circuit transmits switch signal to external circuitry. If switch signal no longer present after suppression time, switch signal deemed transient, and circuit does not pass signal on to external circuitry, as though no transient switch signal. Suppression time preset at value large enough to allow for damping of underlying pressure wave or other mechanical transient.

The Mechanism Underlying Inhibition of Saccadic Return

ERIC Educational Resources Information Center

Ludwig, Casimir J. H.; Farrell, Simon; Ellis, Lucy A.; Gilchrist, Iain D.

2009-01-01

Human observers take longer to re-direct gaze to a previously fixated location. Although there has been some exploration of the characteristics of inhibition of saccadic return (ISR), the exact mechanisms by which ISR operates are currently unknown. In the framework of accumulation models of response times, in which evidence is integrated over…

Carbon Sorption Cryogenic Regenerator

NASA Technical Reports Server (NTRS)

Jones, Jack A.; Petrick, S. Walter; Britcliffe, Michael J.

1989-01-01

Liquid-helium refrigerator includes regenerator filled with carbon sorbent made from Saran polyvinylidene chloride. Material results in lower operating temperatures and longer times between maintenance than comparable refrigerators containing other regenerators. Sorbent material machined to various configurations to fit inside cylindrical regenerator can. Configuration chosen with regard to heat capacity, pressure drop, and rate of sorption.

Laparoscopic and open subtotal colectomies have similar short-term results.

PubMed

Hoogenboom, Froukje J; Bosker, Robbert J I; Groen, Henk; Meijerink, Wilhelmus J H J; Lamme, Bas; Pierie, Jean Pierre E N

2013-01-01

Laparoscopic subtotal colectomy (STC) is a complex procedure. It is possible that short-term benefits for segmental resections cannot be attributed to this complex procedure. This study aims to assess differences in short-term results for laparoscopic versus open STC during a 15-year single-institute experience. We reviewed consecutive patients undergoing laparoscopic or open elective or subacute STC from January 1997 to December 2012. Fifty-six laparoscopic and 50 open STCs were performed. The operation time was significantly longer in the laparoscopic group, median 266 min (range 121-420 min), compared to 153 min (range 90-408 min) in the open group (p < 0.001). Median hospital stay showed no statistical difference, 14 days (range 1-129 days) in the laparoscopic and 13 days (range 1-85 days) in the open group. Between-group postoperative complications were not statistically different. Laparoscopic STC has short-term results similar to the open procedure, except for a longer operation time. The laparoscopic approach for STC is therefore only advisable in selected patients combined with extensive preoperative counseling. Copyright © 2013 S. Karger AG, Basel.

Internally versus externally mediated triggers in the acquisition of visual targets in the horizontal plane.

PubMed

Kolev, Ognyan I; Reschke, Millard F

2014-06-01

In an operational setting acquisition of visual targets using both head and eye movements can be driven by memorized sequence of commands - internal triggering (IT) or by commands issued through secondary operator - external triggering (ET). The primary objective of our research was to examine differences in target acquisition using IT compared with ET. Using a forced time optimal strategy eight subjects were required to acquire targets with angular offsets of ±20°, 30° and 60° along the horizontal plane in both IT and ET conditions. The data showed that the eye/head latency difference in IT condition is longer than that for ET, the target acquisition time is also longer for IT commands. Consistent with this finding were similar results when examining the peak head velocity and peak head acceleration. Under IT protocol head amplitude is higher than when using ET. In conclusion, the study demonstrates that the pattern of performance of target acquisition task is influenced by the way of command triggering. Copyright © 2014 Elsevier B.V. All rights reserved.

The Da Vinci Xi and robotic radical prostatectomy-an evolution in learning and technique.

PubMed

Goonewardene, S S; Cahill, D

2017-06-01

The da Vinci Xi robot has been introduced as the successor to the Si platform. The promise of the Xi is to open the door to new surgical procedures. For robotic-assisted radical prostatectomy (RARP)/pelvic surgery, the potential is better vision and longer instruments. How has the Xi impacted on operative and pathological parameters as indicators of surgical performance? This is a comparison of an initial series of 42 RARPs with the Xi system in 2015 with a series using the Si system immediately before Xi uptake in the same calendar year, and an Si series by the same surgeon synchronously as the Xi series using operative time, blood loss, and positive margins as surrogates of surgical performance. Subjectively and objectively, there is a learning curve to Xi uptake in longer operative times but no impact on T2 positive margins which are the most reflective single measure of RARP outcomes. Subjectively, the vision of the Xi is inferior to the Si system, and the integrated diathermy system and automated setup are quirky. All require experience to overcome. There is a learning curve to progress from the Si to Xi da Vinci surgical platforms, but this does not negatively impact the outcome.

Laparoendoscopic single-site adrenalectomy versus conventional laparoscopic surgery: a systematic review and meta-analysis of observational studies.

PubMed

Wang, Linhui; Wu, Zhenjie; Li, Mingmin; Cai, Chen; Liu, Bing; Yang, Qing; Sun, Yinghao

2013-06-01

To assess the surgical efficacy and potential advantages of laparoendoscopic single-site adrenalectomy (LESS-AD) compared with conventional laparoscopic adrenalectomy (CL-AD) based on published literature. An online systematic search in electronic databasesM including Pubmed, Embase, and the Cochrane Library, as well as manual bibliography searches were performed. All studies that compared LESS-AD with CL-AD were included. The outcome measures were the patient demographics, tumor size, blood loss, operative time, time to resumption of oral intake, hospital stay, postoperative pain, cosmesis satisfaction score, rates of complication, conversion, and transfusion. A meta-analysis of the results was conducted. A total of 443 patients were included: 171 patients in the LESS-AD group and 272 patients in the CL-AD group (nine studies). There was no significant difference between the two groups in any of the demographic parameters expect for lesion size (age: P=0.24; sex: P=0.35; body mass index: P=0.79; laterality: P=0.76; size: P=0.002). There was no significant difference in estimated blood loss, time to oral intake resumption, and length of stay between the two groups. The LESS-AD patients had a significantly lower postoperative visual analog pain score compared with the CL-AD group, but a longer operative time was noted. Both groups had a comparable cosmetic satisfaction score. The two groups had a comparable rate of complication, conversion, and transfusion. In early experience, LESS-AD appears to be a safe and feasible alternative to its conventional laparoscopic counterpart with decreased postoperative pain noted, albeit with a longer operative time. As a promising and emerging minimally invasive technique, however, the current evidence has not verified other potential advantages (ie, cosmesis, recovery time, convalescence, port-related complications, etc.) of LESS-AD.

Single-incision versus conventional three-port laparoscopic appendectomy: A meta-analysis of randomized controlled trials.

PubMed

Chen, Jiang-Ming; Geng, Wei; Xie, Sheng-Xue; Liu, Fu-Bao; Zhao, Yi-Jun; Yu, Li-Quan; Geng, Xiao-Ping

2015-01-01

The aim of this article was to compare the advantages and disadvantages of single-incision laparoscopic appendectomy (SILA) and conventional three-port laparoscopic appendectomy (CTLA). A meta-analysis was performed by analyzing all randomized controlled trials (RCTs) published in English that compared SILA and CTLA for appendicitis in adults and children. These studies compared these two methods from different angles including outcomes of interest, patient characteristics, operative time, pain visual analogue scales scores (VAS scores), length of hospital stay, time to return to full activity, resumption of diet, postoperative complications and cosmetic results The risk ratios (RR) and mean difference (MD) with 95% confidence intervals (CIs) were employed to assess the outcome. Seven recent RCTs encompassing 1170 patients (586 SILA and 584 CTLA cases) were included in this meta-analysis. The pooled results demonstrated that conversion rate, drain inserted, reoperation, length of hospital stay, resumption of normal diet and postoperative complications were statistically comparable between the two groups. The postoperative abdominal pain within 24 h was -0.57 in favor of the SILA technique (p = 0.05). Compared with CTLA, SILA showed a better cosmetic satisfaction score (SMD, 0.58; 95% CI, 0.32-0.83; p < 0.0001) and shorter time to recover normal activity (WMD, -0.69; 95% CI, -1.11-0.26; p = 0.001). However, SILA has a longer operative time (WMD, 5.38; 95% CI, 2.94-7.83; p < 0.0001). In selected patients, SILA was confirmed to be as safe and effective as CTLA. Despite the longer operative time, SILA has higher cosmetic satisfaction and shorter recovery time to normal activity. Due to the limitations of the available data, further research is needed.

Factors determining the smooth flow and the non-operative time in a one-induction room to one-operating room setting

PubMed Central

Mulier, Jan P; De Boeck, Liesje; Meulders, Michel; Beliën, Jeroen; Colpaert, Jan; Sels, Annabel

2015-01-01

Rationale, aims and objectives What factors determine the use of an anaesthesia preparation room and shorten non-operative time? Methods A logistic regression is applied to 18 751 surgery records from AZ Sint-Jan Brugge AV, Belgium, where each operating room has its own anaesthesia preparation room. Surgeries, in which the patient's induction has already started when the preceding patient's surgery has ended, belong to a first group where the preparation room is used as an induction room. Surgeries not fulfilling this property belong to a second group. A logistic regression model tries to predict the probability that a surgery will be classified into a specific group. Non-operative time is calculated as the time between end of the previous surgery and incision of the next surgery. A log-linear regression of this non-operative time is performed. Results It was found that switches in surgeons, being a non-elective surgery as well as the previous surgery being non-elective, increase the probability of being classified into the second group. Only a few surgery types, anaesthesiologists and operating rooms can be found exclusively in one of the two groups. Analysis of variance demonstrates that the first group has significantly lower non-operative times. Switches in surgeons, anaesthesiologists and longer scheduled durations of the previous surgery increases the non-operative time. A switch in both surgeon and anaesthesiologist strengthens this negative effect. Only a few operating rooms and surgery types influence the non-operative time. Conclusion The use of the anaesthesia preparation room shortens the non-operative time and is determined by several human and structural factors. PMID:25496600

Timing of antibiotic prophylaxis in surgery for adult hip fracture.

PubMed Central

Thonse, Raghuram; Sreenivas, Muthyala; Sherman, Kevin P.

2004-01-01

BACKGROUND: Antibiotic prophylaxis is widely used in surgery for hip fractures. METHODS AND RESULTS: In a retrospective study of case notes of 100 patients, frequent inaccuracies in dose administration were observed. This was applicable to both the pre-operative and the postoperative doses. Longer time intervals between the doses, failure to administer the prescribed doses, and failure of proper documentation were observed. CONCLUSIONS: Improvement in the awareness of staff and timely administration of prophylactic antibiotic has resulted from this study. PMID:15239868

Signal Delay-Stability of a Ku-Band Two-Way Satellite Time Transfer Terminal

DTIC Science & Technology

1995-12-01

Robnik Space Research Institute, Graz, Austria Abstract A filly automated huo-way time and frequency transfer ( TWSTFT ) system including a sateme...station. Such a system has been operated for longer than a year together with the two-way satellite time and frequency transfer ( TWSTFT ) station of...accuracy. MEASUREMENT SETUP A detailed description of the TWSTFT system used at TUG is given in [I]. The SATSIM used is of the de Jong type13,41 - this

Work intensity in sacroiliac joint fusion and lumbar microdiscectomy

PubMed Central

Frank, Clay; Kondrashov, Dimitriy; Meyer, S Craig; Dix, Gary; Lorio, Morgan; Kovalsky, Don; Cher, Daniel

2016-01-01

Background The evidence base supporting minimally invasive sacroiliac (SI) joint fusion (SIJF) surgery is increasing. The work relative value units (RVUs) associated with minimally invasive SIJF are seemingly low. To date, only one published study describes the relative work intensity associated with minimally invasive SIJF. No study has compared work intensity vs other commonly performed spine surgery procedures. Methods Charts of 192 patients at five sites who underwent either minimally invasive SIJF (American Medical Association [AMA] CPT® code 27279) or lumbar microdiscectomy (AMA CPT® code 63030) were reviewed. Abstracted were preoperative times associated with diagnosis and patient care, intraoperative parameters including operating room (OR) in/out times and procedure start/stop times, and postoperative care requirements. Additionally, using a visual analog scale, surgeons estimated the intensity of intraoperative care, including mental, temporal, and physical demands and effort and frustration. Work was defined as operative time multiplied by task intensity. Results Patients who underwent minimally invasive SIJF were more likely female. Mean procedure times were lower in SIJF by about 27.8 minutes (P<0.0001) and mean total OR times were lower by 27.9 minutes (P<0.0001), but there was substantial overlap across procedures. Mean preservice and post-service total labor times were longer in minimally invasive SIJF (preservice times longer by 63.5 minutes [P<0.0001] and post-service labor times longer by 20.2 minutes [P<0.0001]). The number of postoperative visits was higher in minimally invasive SIJF. Mean total service time (preoperative + OR time + postoperative) was higher in the minimally invasive SIJF group (261.5 vs 211.9 minutes, P<0.0001). Intraoperative intensity levels were higher for mental, physical, effort, and frustration domains (P<0.0001 each). After taking into account intensity, intraoperative workloads showed substantial overlap. Conclusion Compared to a commonly performed lumbar spine surgical procedure, lumbar microdiscectomy, that currently has a higher work RVU, preoperative, intraoperative, and postoperative workload for minimally invasive SIJF is higher. The work RVU for minimally invasive SIJF should be adjusted upward as the relative amount of work is comparable. PMID:27555790

Selecting patients during the "learning curve" of endoscopic Totally Extraperitoneal (TEP) hernia repair.

PubMed

Schouten, N; Elshof, J W M; Simmermacher, R K J; van Dalen, T; de Meer, S G A; Clevers, G J; Davids, P H P; Verleisdonk, E J M M; Westers, P; Burgmans, J P J

2013-12-01

Totally Extraperitoneal (TEP) hernia surgery is associated with little postoperative pain and a fast recovery, but is a technically demanding operative procedure. Apart from the surgeon's expertise, patient characteristics and hernia-related variations may also affect the operative time and outcome. Patient-related factors predictive of perioperative complications, conversion to open anterior repair, and operative time were studied in a cohort of consecutive patients undergoing TEP hernia repair from 2005 to 2009. A total of 3,432 patients underwent TEP. The mean operative time was 26 min (SD ± 10.9), TEP was converted into an open anterior approach in 26 patients (0.8 %), and perioperative complications were observed in 55 (1.6 %) patients. Multivariable regression analysis showed that a history of abdominal surgery (OR 1.76, 95 per cent confidence interval 1.01-3.06; p = 0.05), and the presence of a scrotal (OR 5.31, 1.20-23.43; p = 0.03) or bilateral hernia (OR 2.25, 1.25-4.06; p = 0.01) were independent predictive factors of perioperative complications. Female gender (OR 5.30. 1.52-18.45; p = 0.01), a history of abdominal surgery (OR 3.96, 1.72- 9.12; p = 0.001), and the presence of a scrotal hernia (OR 34.84, 10.42-116.51, p < 0.001) were predictive factors for conversion. A BMI ≥ 25 (effect size (ES) 1.78, 95 % confidence interval 1.09-2.47; p < 0.001) and the presence of a scrotal (ES 5.81, 1.93-9.68; p = 0.003), indirect (ES 2.78, 2.05- 3.50, p < 0.001) or bilateral hernia (ES 10.19, 9.20-11.08; p < 0.001) were associated with a longer operative time. Certain patient characteristics are, even in experienced TEP surgeons, associated with an increased risk of conversion and complications and a longer operative time. For the surgeon gaining experience with TEP, it seems advisable to select relatively young and slender male patients with a unilateral (non-scrotal) hernia and no previous abdominal surgery to enhance patient safety and 'surgeon comfort'.

Preliminary acclimation strategies for successful startup in conventional biofilters.

PubMed

Elías, Ana; Barona, Astrid; Gallastegi, Gorka; Rojo, Naiara; Gurtubay, Luis; Ibarra-Berastegi, Gabriel

2010-08-01

The question of how to obtain the best inocula for conventional biofilters arises when an acclimation/adaptation procedure is to be applied. Bearing in mind that no standardized procedure for acclimating inocula exists, certain preliminary strategies for obtaining an active inoculum from wastewater treatment sludge are proposed in this work. Toluene was the contaminant to be degraded. Concerning the prior separation of sludge phases, no obvious advantage was found in separating the supernatant phase of the sludge before acclimation. As far as a continuous or discontinuous acclimation mode is concerned, the latter is recommended for rapidly obtaining acclimated sludge samples by operating the system for no longer than 1 month. The continuous mode rendered similar degradation rates, although it required longer operating time. Nevertheless, the great advantage of the continuous system lay in the absence of daily maintenance and the ready availability of the activated sample.

Early cavopulmonary anastomosis in very young infants after the Norwood procedure: impact on oxygenation, resource utilization, and mortality.

PubMed

Jaquiss, Robert D B; Ghanayem, Nancy S; Hoffman, George M; Fedderly, Raymond T; Cava, Joseph R; Mussatto, Kathleen A; Tweddell, James S

2004-04-01

The optimal timing of second-stage palliation after Norwood operations remains undefined. Advantages of early cavopulmonary anastomosis are early elimination of volume load and shortening the high-risk interstage period. Potential disadvantages include severe cyanosis, prolonged pleural drainage and hospitalization, and excess mortality. We reviewed our recent experience to evaluate the safety of early cavopulmonary anastomosis. Eighty-five consecutive patients undergoing post-Norwood operation cavopulmonary anastomosis were divided into group I (cavopulmonary anastomosis at <4 months; n = 33) and group II (cavopulmonary anastomosis at >4 months; n = 52). Groups were compared for age; size; early and late mortality; preoperative, initial postoperative, and discharge oxygen saturation; and duration of mechanical ventilation, intensive care unit stay, pleural drainage, and hospitalization. Group I patients were younger than group II patients (94 +/- 21 days vs 165 +/- 44 days, respectively; P <.001) and smaller (4.8 +/- 0.8 kg vs 5.8 +/- 0.9 kg; P <.001). The preoperative oxygen saturation was not different (group I, 75% +/- 10%; group II, 78% +/- 8%; P =.142). The oxygen saturation was lower immediately after surgery in group I compared with group II (75% +/- 7% vs 81% +/- 7%, respectively; P <.001) but not by discharge (group I, 79% +/- 4%; group II, 80% +/- 4%). Younger patients were ventilated longer (62 +/- 86 hours vs 19 +/- 42 hours; P =.001), in the intensive care unit longer (130 +/- 111 hours vs 104 +/- 94 hours; P =.049), hospitalized longer (12.5 +/- 11.5 days vs 10.3 +/- 14.8 days; P =.012), and required longer pleural drainage (106 +/- 45 hours vs 104 +/- 93 hours; P =.046). Hospital survival was 100% in both groups. Actuarial survival to 12 months was 96% +/- 4% for group I and 96% +/- 3% for group II. Early cavopulmonary anastomosis after the Norwood operation is safe. Younger patients are more cyanotic initially after surgery and have a longer duration of mechanical ventilation, pleural drainage, intensive care unit stay, and hospitalization.

Canister cryogenic system for cooling germanium semiconductor detectors in borehole and marine probes

USGS Publications Warehouse

Boynton, G.R.

1975-01-01

High resolution intrinsic and lithium-drifted germanium gamma-ray detectors operate at about 77-90 K. A cryostat for borehole and marine applications has been designed that makes use of prefrozen propane canisters. Uses of such canisters simplifies cryostat construction, and the rapid exchange of canisters greatly reduces the time required to restore the detector to full holding-time capability and enhances the safety of a field operation where high-intensity 252Cf or other isotopic sources are used. A holding time of 6 h at 86 K was achieved in the laboratory in a simulated borehole probe in which a canister 3.7 cm diameter by 57 cm long was used. Longer holding times can be achieved by larger volume canisters in marine probes. ?? 1975.

Time estimation as a secondary task to measure workload. [attention sharing effect on operator performance

NASA Technical Reports Server (NTRS)

Hart, S. G.

1975-01-01

Variation in the length of time productions and verbal estimates of duration was investigated to determine the influence of concurrent activity on operator time perception. The length of 10-, 20-, and 30-sec intervals produced while performing six different compensatory tracking tasks was significantly longer, 23% on the average, than those produced while performing no other task. Verbal estimates of session duration, taken at the end of each of 27 experimental sessions, reflected a parallel increase in subjective underestimation of the passage of time as the difficulty of the task performed increased. These data suggest that estimates of duration made while performing a manual control task provide stable and sensitive measures of the workload imposed by the primary task, with minimal interference.

Novel phased isolation ditch system for enhanced nutrient removal and its optimal operating strategy.

PubMed

Hong, K i-Ho; Chang, Duk; Hur, Joon-Moo; Han, Sang-Bae

2003-01-01

Phased isolation ditch system with intrachannel clarifier is a simplified novel oxidation ditch system enhancing simultaneous removal of biological nitrogen and phosphorus in municipal wastewater. The system employs two ditches with intra-clarifier, and eliminates external final clarifier, additional preanaerobic reactor, and recycle of sludge and nitrified effluent. Separation of anoxic, anaerobic, and aerobic phases can be accomplished by alternating flow and intermittent aeration. Its pilot-scale system operated at HRTs of 10-21 h, SRTs of 15-41 days, and a cycle times of 2-8 h showed removals of BOD, TN, and TP in the range of mixed liquor temperature above 10 degrees C as high as 88-97, 70-84, and 65-90%, respectively. As the SRTs became longer, the effluent TN decreased dramatically, whereas the effluent TP increased. Higher nitrogen removal was accomplished at shorter cycle times, while better phosphorus removal was achieved in longer cycle times. Optimal system operating strategies maximizing the performance and satisfying both the best nitrogen and phosphorus removals included HRTs ranged 10-14 h, SRTs ranged 25-30 days, and a cycle time of 4 h at the mixed liquor temperature above 10 degrees C. Thus, complete phase separation in a cycle maximizing phosphorus release and uptake as well as nitrification and denitrification was accomplished by scheduling of alternating flow and intermittent aeration in the simplified process scheme. Especially, temporal phase separation for phosphorus release without additional anaerobic reactor was successfully accomplished during anaerobic period without any nitrate interference and carbon-limiting.

Acceptable short-term outcome of laparoscopic subtotal colectomy for inflammatory bowel disease.

PubMed

Frid, Natalie Lassen; Bulut, Orhan; Pachler, Jørn

2013-06-01

Laparoscopic colectomy for both benign and malignant disease, including inflammatory bowel disease (IBD), has recently been shown to have many advantages compared with open surgery. This study aimed to compare the effect of laparoscopic versus open subtotal colectomy (STC) for IBD on overall morbidity. A total of 99 patients undergoing STC for IBD at our institution from 2007 through 2011 were identified. Patients undergoing open STC were compared with patients undergoing laparoscopic STC. Outcomes included 30-day morbidity, conversion to laparotomy, intraoperative blood loss, operative time, admission time, late onset complications and 30-day mortality. Results are presented as median values. A total of 57 patients underwent open STC (Group 1) and 42 patients laparoscopic STC (Group 2). Group 1 comprised 26 males and 31 females, with a median age of 35 years and a body mass index (BMI) of 23.2 kg/m2. Group 2 comprised 18 males and 24 females, with a median age of 34 years and a BMI of 23.5 kg/m2. Group 2 had less morbidity (42.9% versus 75.4%, p < 0.002), reduced blood loss (100 ml versus 200 ml, p < 0.001), longer operative time (193.5 min. versus 128 min., p < 0.001), shorter length of hospital stay (six days versus 16 days, p < 0.001) than Group 1. One patient died (Group 1). There was no difference in late onset complications and no conversions to laparotomy in the laparoscopic group. Laparoscopic STC has a longer operative time, but improves short-term outcomes compared with open surgery. not relevant. not relevant.

Laparoscopic sleeve gastrectomy in patients with abdominoplasty: a case-control study.

PubMed

Saber, Alan A; Shoar, Saeed; El-Matbouly, Moamena; Karem, Mohsen; Bashah, Moataz M; Al Najjar, Ahmad; Alkuwari, Mohammad J; Soltanian, Hooman

2017-02-01

Abdominoplasty is increasingly performed after weight loss surgery. However, performing a laparoscopic sleeve gastrectomy (LSG) after abdominoplasty poses technical challenges. The present study aimed to compare operative events and postoperative outcomes between LSG patients with and without a history of prior abdominoplasty. University hospital, Qatar. A case-control study was conducted on 2 groups of patients with (n = 33) and without (n = 69) prior abdominoplasty who underwent LSG. Patient demographics, baseline characteristics, as well as operative and postoperative events were compared between the 2 groups. A total of 102 patients with an average age of 39.6±7.7 years and body mass index (BMI) of 42.8±5.9 kg/m 2 were included. There were no significant differences between the 2 groups in terms of demographic characteristics, preoperative BMI, and co-morbidities. The number of ports required was significantly higher in the LSG patients with a history of prior abdominoplasty than in the nonabdominoplasty patients. The operation time was also significantly longer in the abdominoplasty patients than in the nonabdominoplasty patients (90.3±36.7 minutes versus 57.1±17.7 minutes; P<.0001). However, no significant differences were observed in terms of postoperative complications, length of hospital stay, and weight loss results. LSG after abdominoplasty is associated with longer operative times and the need for additional port placement to overcome the decreased working space. However, operative strategies should be considered to overcome the technical challenges during LSG in patients who underwent a prior abdominoplasty. Copyright © 2017. Published by Elsevier Inc.

Application of global weather and climate model output to the design and operation of wind-energy systems

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

Curry, Judith

This project addressed the challenge of providing weather and climate information to support the operation, management and planning for wind-energy systems. The need for forecast information is extending to longer projection windows with increasing penetration of wind power into the grid and also with diminishing reserve margins to meet peak loads during significant weather events. Maintenance planning and natural gas trading is being influenced increasingly by anticipation of wind generation on timescales of weeks to months. Future scenarios on decadal time scales are needed to support assessment of wind farm siting, government planning, long-term wind purchase agreements and the regulatorymore » environment. The challenge of making wind forecasts on these longer time scales is associated with a wide range of uncertainties in general circulation and regional climate models that make them unsuitable for direct use in the design and planning of wind-energy systems. To address this challenge, CFAN has developed a hybrid statistical/dynamical forecasting scheme for delivering probabilistic forecasts on time scales from one day to seven months using what is arguably the best forecasting system in the world (European Centre for Medium Range Weather Forecasting, ECMWF). The project also provided a framework to assess future wind power through developing scenarios of interannual to decadal climate variability and change. The Phase II research has successfully developed an operational wind power forecasting system for the U.S., which is being extended to Europe and possibly Asia.« less

75 FR 9538 - Proposed Modification of Class B Airspace; Charlotte, NC

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-03

... its parachute jump activities, safety and on the future growth and expansion of its operations at DCM... probability of ``go arounds'' wherein the jump aircraft is instructed by ATC to withhold jumpers due to... and longer time at jump altitude (i.e., 13,500 feet MSL) for jumpers that are not equipped with...

Legal Problems of Religious and Private Schools. Third Edition. NOLPE Monograph Series, No. 53.

ERIC Educational Resources Information Center

Mawdsley, Ralph D.

The almost universal doctrine of charitable immunity was traditionally justified at one time because of the altruistic nature of charities. The reasons for abolition of charitable immunity in most states have generally been two-fold: (1) charities are no longer low-budget, marginal operations; (2) the risk of crippling verdicts can be minimized…

48 CFR 970.2204-1-1 - Administrative controls and criteria for application of the Davis-Bacon Act in operational or...

Code of Federal Regulations, 2010 CFR

2010-10-01

... designed for use in a succession of experimental programs over a longer period of time. Examples of loop...) Experimental development of equipment, processes, or devices, including assembly, fitting, installation... for the purpose of conducting a test or experiment. The design may be only conceptual in character...

48 CFR 970.2204-1-1 - Administrative controls and criteria for application of the Davis-Bacon Act in operational or...

Code of Federal Regulations, 2013 CFR

2013-10-01

... designed for use in a succession of experimental programs over a longer period of time. Examples of loop...) Experimental development of equipment, processes, or devices, including assembly, fitting, installation... for the purpose of conducting a test or experiment. The design may be only conceptual in character...

48 CFR 970.2204-1-1 - Administrative controls and criteria for application of the Davis-Bacon Act in operational or...

Code of Federal Regulations, 2012 CFR

2012-10-01

... designed for use in a succession of experimental programs over a longer period of time. Examples of loop...) Experimental development of equipment, processes, or devices, including assembly, fitting, installation... for the purpose of conducting a test or experiment. The design may be only conceptual in character...

48 CFR 970.2204-1-1 - Administrative controls and criteria for application of the Davis-Bacon Act in operational or...

Code of Federal Regulations, 2011 CFR

2011-10-01

... designed for use in a succession of experimental programs over a longer period of time. Examples of loop...) Experimental development of equipment, processes, or devices, including assembly, fitting, installation... for the purpose of conducting a test or experiment. The design may be only conceptual in character...

48 CFR 970.2204-1-1 - Administrative controls and criteria for application of the Davis-Bacon Act in operational or...

Code of Federal Regulations, 2014 CFR

2014-10-01

... designed for use in a succession of experimental programs over a longer period of time. Examples of loop...) Experimental development of equipment, processes, or devices, including assembly, fitting, installation... for the purpose of conducting a test or experiment. The design may be only conceptual in character...

Mini-Mega-TORTORA wide-field monitoring system with sub-second temporal resolution: first year of operation

NASA Astrophysics Data System (ADS)

Karpov, S.; Beskin, G.; Biryukov, A.; Bondar, S.; Ivanov, E.; Katkova, E.; Perkov, A.; Sasyuk, V.

2016-12-01

Here we present the summary of first years of operation and the first results of a novel 9-channel wide-field optical monitoring system with sub-second temporal resolution, Mini-Mega-TORTORA (MMT-9), which is in operation now at Special Astrophysical Observatory on Russian Caucasus. The system is able to observe the sky simultaneously in either wide (˜900 square degrees) or narrow (˜100 square degrees) fields of view, either in clear light or with any combination of color (Johnson-Cousins B, V or R) and polarimetric filters installed, with exposure times ranging from 0.1 s to hundreds of seconds. The real-time system data analysis pipeline performs automatic detection of rapid transient events, both near-Earth and extragalactic. The objects routinely detected by MMT include faint meteors and artificial satellites. The pipeline for a longer time scales variability analysis is still in development.

[Robots in general surgery: present and future].

PubMed

Galvani, Carlos; Horgan, Santiago

2005-09-01

Robotic surgery is an emerging technology. We began to use this technique in 2000, after it was approved by the Food and Drug Administration. Our preliminary experience was satisfactory. We report 4 years' experience of using this technique in our institution. Between August 2000 and December 2004, 399 patients underwent robotic surgery using the Da Vinci system. We performed 110 gastric bypass procedures, 30 Lap band, 59 Heller myotomies, 12 Nissen fundoplications, 6 epiphrenic diverticula, 18 total esophagectomies, 3 esophageal leiomyoma resections, 1 pyloroplasty, 2 gastrojejunostomies, 2 transduodenal sphincteroplasties, 10 adrenalectomies and 145 living-related donor nephrectomies. Operating times for fundoplications and Lap band were longer. After the learning curve, the operating times and morbidity of the remaining procedures were considerably reduced. Robot-assisted surgery allows advanced laparoscopic procedures to be performed with enhanced results given that it reduces the learning curve as measured by operating time and morbidity.

A semi-floating gate memory based on van der Waals heterostructures for quasi-non-volatile applications

NASA Astrophysics Data System (ADS)

Liu, Chunsen; Yan, Xiao; Song, Xiongfei; Ding, Shijin; Zhang, David Wei; Zhou, Peng

2018-05-01

As conventional circuits based on field-effect transistors are approaching their physical limits due to quantum phenomena, semi-floating gate transistors have emerged as an alternative ultrafast and silicon-compatible technology. Here, we show a quasi-non-volatile memory featuring a semi-floating gate architecture with band-engineered van der Waals heterostructures. This two-dimensional semi-floating gate memory demonstrates 156 times longer refresh time with respect to that of dynamic random access memory and ultrahigh-speed writing operations on nanosecond timescales. The semi-floating gate architecture greatly enhances the writing operation performance and is approximately 106 times faster than other memories based on two-dimensional materials. The demonstrated characteristics suggest that the quasi-non-volatile memory has the potential to bridge the gap between volatile and non-volatile memory technologies and decrease the power consumption required for frequent refresh operations, enabling a high-speed and low-power random access memory.

Oncoplastic round block technique has comparable operative parameters as standard wide local excision: a matched case-control study.

PubMed

Lim, Geok-Hoon; Allen, John Carson; Ng, Ruey Pyng

2017-08-01

Although oncoplastic breast surgery is used to resect larger tumors with lower re-excision rates compared to standard wide local excision (sWLE), criticisms of oncoplastic surgery include a longer-albeit, well concealed-scar, longer operating time and hospital stay, and increased risk of complications. Round block technique has been reported to be very suitable for patients with relatively smaller breasts and minimal ptosis. We aim to determine if round block technique will result in operative parameters comparable with sWLE. Breast cancer patients who underwent a round block procedure from 1st May 2014 to 31st January 2016 were included in the study. These patients were then matched for the type of axillary procedure, on a one to one basis, with breast cancer patients who had undergone sWLE from 1st August 2011 to 31st January 2016. The operative parameters between the 2 groups were compared. 22 patients were included in the study. Patient demographics and histologic parameters were similar in the 2 groups. No complications were reported in either group. The mean operating time was 122 and 114 minutes in the round block and sWLE groups, respectively (P=0.64). Length of stay was similar in the 2 groups (P=0.11). Round block patients had better cosmesis and lower re-excision rates. A higher rate of recurrence was observed in the sWLE group. The round block technique has comparable operative parameters to sWLE with no evidence of increased complications. Lower re-excision rate and better cosmesis were observed in the round block patients suggesting that the round block technique is not only comparable in general, but may have advantages to sWLE in selected cases.

Co-surgeons in breast reconstructive microsurgery: What do they bring to the table?

PubMed

Haddock, Nicholas T; Kayfan, Samar; Pezeshk, Ronnie A; Teotia, Sumeet S

2018-01-01

Current research within other surgical specialties suggests that a co-surgeon approach may reduce operative times and complications associated with complex bilateral procedures, possibly leading to improved patient and surgical outcomes. We sought to evaluate the role of the co-surgery team and its development in free flap breast reconstruction. A retrospective review of free-flap breast reconstruction by two surgeons from 2011 to 2016 was conducted. We analyzed 128 patients who underwent bilateral-DIEP breast. Surgical groups were: single-surgeon reconstruction (SSR; 35 patients), co-surgery where both surgeons are present for entire reconstruction (CSR-I; 69 patients), and co-surgery reconstruction where co-surgeons appropriately assist in two concurrent or staggered cases (CSR-II; 24 patients). Efficiency data collected was OR time and patient length-of-stay (LOS). The rate of flap-failure, return to OR, infection, wound breakdown, seroma, hematoma, and PE/DVT were compared. Single-surgeon reconstruction had significantly longer OR time (678 vs. 485 min, P < .0001), LOS (5 vs. 3.9 days, P < .001), higher wound occurrences of the umbilical site that required surgical correction [11.4 percent (n = 4) vs. 1.5% (n = 1); P < .043] compared to CSR-I. Similarly, SSR had significantly longer average OR time (678 vs. 527 min P < .0001), average LOS (5 vs. 4 days, P = .0005) when compared with CSR-II. There were no total increased patient related complications associated with co-surgery (CSR-I or II). The addition of a co-surgeon, even with concurrent surgery, reduces operative time, average patient LOS, and postoperative complications. This work lends a strong credence that co-surgery model is associated with increased operative efficiency. © 2017 Wiley Periodicals, Inc.

Optimising recovery after surgery: Predictors of early discharge and hospital readmission.

PubMed

Carter, Jonathan; Philp, Shannon; Wan, King M

2016-10-01

Fast track surgery (FTS) programs minimise the stress response after surgery and allow for enhanced recovery. To document the frequency and incidence of adverse events in patients enrolled on a FTS program and to investigate factors associated with shorter length of stay and readmission to hospital. A seven-year updated surgical audit of patients undergoing laparotomy for suspected or confirmed malignancy on a FTS program. Five hundred and fifty patients comprise the study group. Average age and body mass index (BMI) were 55 years and 28, respectively. Mean length of stay (LOS) was 3.4 days with 194 (35%) patients discharged on day 2. Six (1%) patients had confirmed venous thromboembolism (VTE), three of whom were diagnosed on pre-operative imaging. Overall, transfusion rate was 5%. Adverse events in decreasing frequency were hospital readmission (4%) and significant wound infection (3%). All other adverse events were uncommon with rates <0.5%. Factors associated with a discharge on or after day 3 include age, pathology, Eastern Cooperative Oncology Group performance status, incision type, operating time, blood transfusion and cyclo-oxygenase 2 inhibitors. Factors associated with hospital readmission include longer operating time, performance of lymph node sampling/dissection, longer LOS, development of wound infection, febrile morbidity, return to the operating room, unplanned intensive care unit admission and presence of other complications. Patients managed by a FTS protocol can expect enhanced outcomes when compared to historical controls. © 2016 The Royal Australian and New Zealand College of Obstetricians and Gynaecologists.

Resource Optimization Techniques and Security Levels for Wireless Sensor Networks Based on the ARSy Framework.

PubMed

Parenreng, Jumadi Mabe; Kitagawa, Akio

2018-05-17

Wireless Sensor Networks (WSNs) with limited battery, central processing units (CPUs), and memory resources are a widely implemented technology for early warning detection systems. The main advantage of WSNs is their ability to be deployed in areas that are difficult to access by humans. In such areas, regular maintenance may be impossible; therefore, WSN devices must utilize their limited resources to operate for as long as possible, but longer operations require maintenance. One method of maintenance is to apply a resource adaptation policy when a system reaches a critical threshold. This study discusses the application of a security level adaptation model, such as an ARSy Framework, for using resources more efficiently. A single node comprising a Raspberry Pi 3 Model B and a DS18B20 temperature sensor were tested in a laboratory under normal and stressful conditions. The result shows that under normal conditions, the system operates approximately three times longer than under stressful conditions. Maintaining the stability of the resources also enables the security level of a network's data output to stay at a high or medium level.

Resource Optimization Techniques and Security Levels for Wireless Sensor Networks Based on the ARSy Framework

PubMed Central

Kitagawa, Akio

2018-01-01

Wireless Sensor Networks (WSNs) with limited battery, central processing units (CPUs), and memory resources are a widely implemented technology for early warning detection systems. The main advantage of WSNs is their ability to be deployed in areas that are difficult to access by humans. In such areas, regular maintenance may be impossible; therefore, WSN devices must utilize their limited resources to operate for as long as possible, but longer operations require maintenance. One method of maintenance is to apply a resource adaptation policy when a system reaches a critical threshold. This study discusses the application of a security level adaptation model, such as an ARSy Framework, for using resources more efficiently. A single node comprising a Raspberry Pi 3 Model B and a DS18B20 temperature sensor were tested in a laboratory under normal and stressful conditions. The result shows that under normal conditions, the system operates approximately three times longer than under stressful conditions. Maintaining the stability of the resources also enables the security level of a network’s data output to stay at a high or medium level. PMID:29772773

Quantification of reaction time and time perception during Space Shuttle operations

NASA Technical Reports Server (NTRS)

Ratino, D. A.; Repperger, D. W.; Goodyear, C.; Potor, G.; Rodriguez, L. E.

1988-01-01

A microprocessor-based test battery containing simple reaction time, choice reaction time, and time perception tasks was flown aboard a 1985 Space Shuttle flight. Data were obtained from four crew members. Individual subject means indicate a correlation between change in reaction time during the flight and the presence of space motion sickness symptoms. The time perception task results indicate that the shortest duration task time (2 s) is progressively overestimated as the mission proceeds and is statistically significant when comparing preflight and postflight baselines. The tasks that required longer periods of time to estimate (8, 12, and 16 s) are less affected.

Is larger scoliosis curve magnitude associated with increased perioperative health-care resource utilization?: a multicenter analysis of 325 adolescent idiopathic scoliosis curves.

PubMed

Miyanji, Firoz; Slobogean, Gerard P; Samdani, Amer F; Betz, Randal R; Reilly, Christopher W; Slobogean, Bronwyn L; Newton, Peter O

2012-05-02

The treatment of patients with large adolescent idiopathic scoliosis curves has been associated with increased surgical complexity. The purpose of this study was to determine whether surgical correction of larger adolescent idiopathic scoliosis curves increased the utilization of health-care resources and to identify potential predictors associated with increased perioperative health-care resource utilization. A nested cohort of patients with adolescent idiopathic scoliosis with Lenke type 1A and 1B curves were identified from a prospective longitudinal multicenter database. Four perioperative outcomes were selected as the primary health-care resource utilization outcomes of interest: operative time, number of vertebral levels instrumented, duration of hospitalization, and allogeneic blood transfusion. The effect of curve magnitude on these outcomes was assessed with use of univariate and multivariate regression. Three hundred and twenty-five patients with a mean age of 15 ± 2 years were included. The mean main thoracic curve was 54.4° ± 7.8°. Larger curves were associated with longer operative time (p = 0.03), a greater number of vertebral levels instrumented (p = 0.0005), and the need for blood transfusion (with every 10° increase associated with 1.5 times higher odds of receiving a transfusion). In addition to curve magnitude, surgical center, bone graft method, and upper and lower instrumented levels were strong predictors of operative time (R2 = 0.76). The duration of hospitalization was influenced by the surgical center and intraoperative blood loss (R2 < 0.4), whereas the number of levels instrumented was influenced by the curve magnitude, curve correction percentage, upper instrumented vertebra, and surgical center (R2 = 0.64). Correction of larger curves was associated with increased utilization of perioperative health-care resources, specifically longer operative time, a greater number of vertebral levels instrumented, and higher odds of receiving a blood transfusion.

Maylard incision in gynecologic surgery: 4-year experience in Thammasat University Hospital.

PubMed

Manusook, Sakol; Suwannarurk, Komsun; Pongrojpaw, Densak; Bhamarapravatana, Kornkarn

2014-08-01

To present the results of Maylard incisionfor gynecologic surgery in Thammasat University Hospital during the past four years. A retrospective study of gynecologic surgery performed via the Maylard muscle cutting incision compare to Pfannenstiel muscle splitting and midline incision. Data came from subjects who underwent gynecologic surgey at Thammasat University Hospital, Pathumthani, Thailand friom January 2010 to December 2013. In the period of 4 years, there were 283 cases of elective surgery that performed via Maylard, Pfannenstiel and midline incision by the single experience gynecologic surgeon team. One hundred and six cases were performed via Maylard incision technique. The remaining 59 and 118 cases were performed via Pfannenstiel and midline incision technique, respectively. Two-thirds and one-thirds of cases underwent hysterectomy and conservative surgery, respectively. Benign conditions were the major indicationfor surgery at the percentage of 83.4. Operative results were not significantly different from well-known midline and Pfannenstiel incision in terms of blood loss, time to first meal and postoperative pain. Operative time in Maylard incision was longer than in Pfannenstiel incision. Length of stay in Maylard incision was longer than Pfannenstiel but shorter than midline incision. Overall complications (eoperation, bowel injuries, urinary bladder injuries and blood transfusion rate) were not significantly different. Maylard incision provides similar operative results with midline and Pfannenstiel technique. Even though it takes more time for abdominal entry but it gives more operative exposure than Pfannenstiel incision. In the woman with previous low transverse scar and gynaecologic surgery is needed, Maylard incision could be an optional technique that provides cosmetic and successfud results. Hand on training for Maylard incision from their mentors should be encouraged to more practice.

Acute appendicitis in the public and private sectors in Cape Town, South Africa.

PubMed

Yang, Estin; Cook, Colin; Kahn, Delawir

2015-07-01

South Africa has a low incidence of acute appendicitis, but poor outcomes. However, South African studies on appendicitis focus solely on public hospitals, neglecting those who utilize private facilities. This study aims to compare appendicitis characteristics and outcomes in public and private hospitals in South Africa. A prospective cohort study was conducted among two public and three private hospitals in the Cape Town metropole, from September 2013 to March 2014. Hospital records, operative notes, and histology results were reviewed for patients undergoing appendectomy for acute appendicitis. Patients were interviewed during their hospitalization and followed up at monthly intervals until normal function was attained. A total of 134 patients were enrolled, with 73 in the public and 61 in the private sector. Education and employment were higher among private sector patients. Public sector patients had a higher rupture rate (30.6 vs 13.2 %, p = 0.023). Times to presentation were not statistically different between the two cohorts. Public sector patients had longer hospital stays (5.3 vs 2.9 days, p = 0.036) and longer return to work times (23.0 vs 12.1 days, p < 0.0001). Although complication rates were similar, complications in public hospitals were more severe. Public sector patients in South Africa with appendicitis have higher rupture rates, worse complications, longer hospital stays, and longer recoveries than private sector patients. Patients with perforation had longer delays in presentation than patients without perforation.

Comparing Coordinated Versus Sequential Salpingo-Oophorectomy for BRCA1 and BRCA2 Mutation Carriers With Breast Cancer.

PubMed

S Chapman, Jocelyn; Roddy, Erika; Panighetti, Anna; Hwang, Shelley; Crawford, Beth; Powell, Bethan; Chen, Lee-May

2016-12-01

Women with breast cancer who carry BRCA1 or BRCA2 mutations must also consider risk-reducing salpingo-oophorectomy (RRSO) and how to coordinate this procedure with their breast surgery. We report the factors associated with coordinated versus sequential surgery and compare the outcomes of each. Patients in our cancer risk database who had breast cancer and a known deleterious BRCA1/2 mutation before undergoing breast surgery were included. Women who chose concurrent RRSO at the time of breast surgery were compared to those who did not. Sixty-two patients knew their mutation carrier status before undergoing breast cancer surgery. Forty-three patients (69%) opted for coordinated surgeries, and 19 (31%) underwent sequential surgeries at a median follow-up of 4.4 years. Women who underwent coordinated surgery were significantly older than those who chose sequential surgery (median age of 45 vs. 39 years; P = .025). There were no differences in comorbidities between groups. Patients who received neoadjuvant chemotherapy were more likely to undergo coordinated surgery (65% vs. 37%; P = .038). Sequential surgery patients had longer hospital stays (4.79 vs. 3.44 days, P = .01) and longer operating times (8.25 vs. 6.38 hours, P = .006) than patients who elected combined surgery. Postoperative complications were minor and were no more likely in either group (odds ratio, 4.76; 95% confidence interval, 0.56-40.6). Coordinating RRSO with breast surgery is associated with receipt of neoadjuvant chemotherapy, longer operating times, and hospital stays without an observed increase in complications. In the absence of risk, surgical options can be personalized. Copyright © 2016 Elsevier Inc. All rights reserved.

Analysis of oil-pipeline distribution of multiple products subject to delivery time-windows

NASA Astrophysics Data System (ADS)

Jittamai, Phongchai

This dissertation defines the operational problems of, and develops solution methodologies for, a distribution of multiple products into oil pipeline subject to delivery time-windows constraints. A multiple-product oil pipeline is a pipeline system composing of pipes, pumps, valves and storage facilities used to transport different types of liquids. Typically, products delivered by pipelines are petroleum of different grades moving either from production facilities to refineries or from refineries to distributors. Time-windows, which are generally used in logistics and scheduling areas, are incorporated in this study. The distribution of multiple products into oil pipeline subject to delivery time-windows is modeled as multicommodity network flow structure and mathematically formulated. The main focus of this dissertation is the investigation of operating issues and problem complexity of single-source pipeline problems and also providing solution methodology to compute input schedule that yields minimum total time violation from due delivery time-windows. The problem is proved to be NP-complete. The heuristic approach, a reversed-flow algorithm, is developed based on pipeline flow reversibility to compute input schedule for the pipeline problem. This algorithm is implemented in no longer than O(T·E) time. This dissertation also extends the study to examine some operating attributes and problem complexity of multiple-source pipelines. The multiple-source pipeline problem is also NP-complete. A heuristic algorithm modified from the one used in single-source pipeline problems is introduced. This algorithm can also be implemented in no longer than O(T·E) time. Computational results are presented for both methodologies on randomly generated problem sets. The computational experience indicates that reversed-flow algorithms provide good solutions in comparison with the optimal solutions. Only 25% of the problems tested were more than 30% greater than optimal values and approximately 40% of the tested problems were solved optimally by the algorithms.

Anterolateral minithoracotomy versus median sternotomy for the treatment of congenital heart defects: a meta-analysis and systematic review.

PubMed

Ding, Chao; Wang, Chunmao; Dong, Aiqiang; Kong, Minjian; Jiang, Daming; Tao, Kaiyu; Shen, Zhonghua

2012-05-04

Anterolateral Minithoracotomy (ALMT) for the radical correction of Congenital Heart Defects is an alternative to Median Sternotomy (MS) due to reduce operative trauma accelerating recovery and yield a better cosmetic outcome after surgery. Our purpose is to conduct whether ALMT would bring more short-term benefits to patients than conventional Median Sternotomy by using a meta-analysis of case-control study in the published English Journal. 6 case control studies published in English from 1997 to 2011 were identified and synthesized to compare the short-term postoperative outcomes between ALMT and MS. These outcomes were cardiopulmonary bypass time, aortic cross-clamp time, intubation time, intensive care unit stay time, and postoperative hospital stay time. ALMT had significantly longer cardiopulmonary bypass times (8.00 min more, 95% CI 0.36 to 15.64 min, p = 0.04). Some evidence proved that aortic cross-clamp time of ALMT was longer, yet not significantly (2.38 min more, 95% CI -0.15 to 4.91 min, p = 0.06). In addition, ALMT had significantly shorter intubation time (1.66 hrs less, 95% CI -3.05 to -0.27 hrs, p = 0.02). Postoperative hospital stay time was significantly shorter with ALMT (1.52 days less, 95% CI -2.71 to -0.33 days, p = 0.01). Some evidence suggested a reduction in ICU stay time in the ALMT group. However, this did not prove to be statistically significant (0.88 days less, 95% CI -0.81 to 0.04 days, p = 0.08). ALMT can bring more benefits to patients with Congenital Heart Defects by reducing intubation time and postoperative hospital stay time, though ALMT has longer CPB time and aortic cross-clamp time.

Numerical Response Surfaces of Volume of Ablation and Retropulsion Amplitude by Settings of Ho:YAG Laser Lithotripter

PubMed Central

Rutherford, Jonathan; Solomon, Metasebya; Cheng, Brian; Xuan, Jason R.; Gong, Jason; Yu, Honggang; Xia, Michael L. D.; Yang, Xirong; Hasenberg, Thomas; Curran, Sean

2018-01-01

Objectives Although laser lithotripsy is now the preferred treatment option for urolithiasis due to shorter operation time and a better stone-free rate, the optimal laser settings for URS (ureteroscopic lithotripsy) for less operation time remain unclear. The aim of this study was to look for quantitative responses of calculus ablation and retropulsion by performing operator-independent experiments to determine the best fit versus the pulse energy, pulse width, and the number of pulses. Methods A lab-built Ho:YAG laser was used as the laser pulse source, with a pulse energy from 0.2 J up to 3.0 J and a pulse width of 150 μs up to 1000 μs. The retropulsion was monitored using a high-speed camera, and the laser-induced craters were evaluated with a 3-D digital microscope. The best fit to the experimental data is done by a design of experiment software. Results The numerical formulas for the response surfaces of ablation speed and retropulsion amplitude are generated. Conclusions The longer the pulse, the less the ablation or retropulsion, while the longer pulse makes the ablation decrease faster than the retropulsion. The best quadratic fit of the response surface for the volume of ablation varied nonlinearly with pulse duration and pulse number. PMID:29707187

The use of theatre time for paediatric dentistry under general anaesthesia.

PubMed

Foley, Jennifer; Soldani, Francesca

2007-01-01

The aim of this paper was to determine the use of theatre time for all procedures performed under general anaesthetic on a paediatric dental list. A prospective study of paediatric dental general anaesthetic procedures was undertaken at Ninewells Hospital and Medical School, NHS Tayside, Dundee, UK. Data were collected prospectively for 71 operating lists over a 3-year period from April 2003 to March 2006. Both operator status and the procedure being undertaken were recorded. In addition, pre-anaesthetic, anaesthetic, operating and disconnection times were recorded. Of the 71 lists examined, 61 either finished early or on time, with a median unused time of 32.50 min (interquartile range = 19.50, 50.00 min), whilst 10 lists finished late with a median overrun time of 30.50 min (interquartile range = 9.25, 45.50 min). Comparing lists which finished late with those which were completed within time, the median pre-anaesthetic time was significantly longer (Mann-Whitney U-test, W = 20.05, P = 0.048). Overall, the theatre was in use for 78.22% of time combining pre-anaesthetic, anaesthetic, operating and disconnection times; hence, there was poor time utilization of theatre for 21.78% of the total theatre time. Overall, 85.9% of theatre sessions for dental procedures under general anaesthetic in children finished early or on time. Where lists finished late, the duration of the pre-anaesthetic time appeared to be the significant factor.

Online residence time distribution measurement of thermochemical biomass pretreatment reactors

DOE PAGES

Sievers, David A.; Kuhn, Erik M.; Stickel, Jonathan J.; ...

2015-11-03

Residence time is a critical parameter that strongly affects the product profile and overall yield achieved from thermochemical pretreatment of lignocellulosic biomass during production of liquid transportation fuels. The residence time distribution (RTD) is one important measure of reactor performance and provides a metric to use when evaluating changes in reactor design and operating parameters. An inexpensive and rapid RTD measurement technique was developed to measure the residence time characteristics in biomass pretreatment reactors and similar equipment processing wet-granular slurries. Sodium chloride was pulsed into the feed entering a 600 kg/d pilot-scale reactor operated at various conditions, and aqueous saltmore » concentration was measured in the discharge using specially fabricated electrical conductivity instrumentation. This online conductivity method was superior in both measurement accuracy and resource requirements compared to offline analysis. Experimentally measured mean residence time values were longer than estimated by simple calculation and screw speed and throughput rate were investigated as contributing factors. In conclusion, a semi-empirical model was developed to predict the mean residence time as a function of operating parameters and enabled improved agreement.« less

Providing Affordable Access to Higher Education through Year-Round Operation: A Case Study in Public Higher Education

ERIC Educational Resources Information Center

Buttermore, John; Baker, Eliott; Culp, David

2014-01-01

Time-compressed courses at state-supported universities have served a variety of purposes. It has been traditional to set scheduling policies that would make summer and winter sessions self-funding. They have not been viewed, however, as potential enrollment generators. This is an opportunity that can no longer be overlooked. This paper describes…

Enhancing The Army Operations Process Through The Incorportation of Holography

DTIC Science & Technology

2017-06-09

the process and gives the user the sense of a noninvasive enhancement to quickly make decisions . Processes and information no longer create...mentally overlaying it onto the process . Data now augments reality and is a noninvasive process to decision making . v ACKNOWLEDGMENTS This paper...environment, augmented on top of reality decreases the amount of time needed to make decisions

Development of a subway operation incident delay model using accelerated failure time approaches.

PubMed

Weng, Jinxian; Zheng, Yang; Yan, Xuedong; Meng, Qiang

2014-12-01

This study aims to develop a subway operational incident delay model using the parametric accelerated time failure (AFT) approach. Six parametric AFT models including the log-logistic, lognormal and Weibull models, with fixed and random parameters are built based on the Hong Kong subway operation incident data from 2005 to 2012, respectively. In addition, the Weibull model with gamma heterogeneity is also considered to compare the model performance. The goodness-of-fit test results show that the log-logistic AFT model with random parameters is most suitable for estimating the subway incident delay. First, the results show that a longer subway operation incident delay is highly correlated with the following factors: power cable failure, signal cable failure, turnout communication disruption and crashes involving a casualty. Vehicle failure makes the least impact on the increment of subway operation incident delay. According to these results, several possible measures, such as the use of short-distance and wireless communication technology (e.g., Wifi and Zigbee) are suggested to shorten the delay caused by subway operation incidents. Finally, the temporal transferability test results show that the developed log-logistic AFT model with random parameters is stable over time. Copyright © 2014 Elsevier Ltd. All rights reserved.

Antibiotics in surgical treatment of acute abscesses.

PubMed Central

Blick, P W; Flowers, M W; Marsden, A K; Wilson, D H; Ghoneim, A T

1980-01-01

A four-way, double-blind, prospective trial of treatment of abscesses by incision, curettage, and primary closure with and without antibiotic cover (clindamycin injection before operation or capsules after operation, or both) was conducted. There was no appreciable difference in mean healing time between the patients given both the antibiotic injection and the antibiotic capsules and those given the injection and placebo capsules, whereas healing times in those given the placebo injection and antibiotic capsules or placebo only were appreciably longer. Four of the patients who were not given the antibiotic injection developed bacteraemia; one patient who was given the antibiotic injection also developed a bacteraemia, but this was caused by clindamycin-resistant bacteria. These results show that a single injection of an effective antibiotic before operation is sufficient to protect the patient against bacteraemia and permit optimum healing. PMID:7000250

A study of the method of the video image presentation for the manipulation of forceps.

PubMed

Kono, Soichi; Sekioka, Toshiharu; Matsunaga, Katsuya; Shidoji, Kazunori; Matsuki, Yuji

2005-01-01

Recently, surgical operations have sometimes been tried under laparoscopic video images using teleoperation robots or forceps manipulators. Therefore, in this paper, forceps manipulation efficiencies were evaluated when images for manipulation had some transmission delay (Experiment 1), and when the convergence point of the stereoscopic video cameras was either fixed and variable (Experiment 2). The operators' tasks in these experiments were sewing tasks which simulated telesurgery under 3-dimensional scenography. As a result of experiment 1, the operation at a 200+/-100 ms delay was kept at almost the same accuracy as that without delay. As a result of experiment 2, work accuracy was improved by using the zooming lens function; however the working time became longer. These results seemed to show the relation of a trade-off between working time and working accuracy.

Surgical Results of the Cephalomedullary Nail for the Femoral Intertrochanteric Fracture: Comparison between Non-experienced Surgeons and Experienced Surgeon

PubMed Central

Seo, Jae-Seong; Min, Hak-Jin; Kim, Dong Min; Oh, Seung-Min

2016-01-01

Purpose Cephalomedullary nail (CM nail) in the treatment of femoral intertrochanteric fractures is in the lime light in recent years. The purpose of this study is to compare surgical outcomes between experienced surgeon and non-experienced surgeons in respect of CM nail for femoral intertrochanteric fractures. Materials and Methods The 129 patients underwent CM nail for femoral intertrochanteric fracture more than six months of follow-up from April 2011 to March 2014 in Seoul Medical Center (Seoul, Korea) were participated in this study. For this study, group A consisted of experienced surgeons who performed more than 500 times of CM nail, and group B consisted of non-experienced surgeons who performed less than 50 times of CM nail. Clinical and radiologic outcomes, complications and the need for reoperation between both groups were compared in the study. Results According to clinical result, both the mean operation time and transfusion volume were significantly longer and greater in group B (P<0.05). In the radiologic outcomes, adequacy of reduction, tip-apex distance and numbers of case placed in the Cleveland zones 5, 6 and 8; there was no statistical difference between both groups. Moreover, rate of complication and reoperation had same results as radiologic outcomes. Conclusion There was no significant difference with statistical data in complications from CM nail for femoral intertrochanteric fractures between experienced surgeon and non-experienced surgeon. Although the operation time and transfusion volume were significantly longer and greater in the case of operation by non-experienced surgeon, satisfactory performance was seen in the complications and the need for reoperation. PMID:28097112

[Clinical analysis of percutaneous nephrolithotomy for staghorn calculi with different stone branch number].

PubMed

Qi, Shi-yong; Zhang, Zhi-hong; Zhang, Chang-wen; Liu, Ran-lu; Shi, Qi-duo; Xu, Yong

2013-12-01

To investigate the impact of staghorn stone branch number on outcomes of percutaneous nephrolithotomy (PNL). From January 2009 to January 2013, the 371 patients with staghorn stones who were referred to our hospital for PNL were considered for this study. All calculi were showed with CT 3-dimentional reconstruction (3-DR) imaging. The computerized database of the patients had been reviewed. Our exclusion criterion was patients with congenital renal anomalies, such as horse-shoe and ectopic kidneys. And borderline stones that branched to one major calyx only were also not included. From 3-DR images, the number of stone branching into minor renal calices was recorded. We made "3" as the branch breakdown between groups. And the patients were divided into four groups. The number of percutaneous tract, operative time, staged PNL, intra-operative blood loss, complications, stone clearance rate, and postoperative hospital day were compared. The 371 patients (386 renal units) underwent PNL successfully, included 144 single-tract PNL, 242 multi-tract PNL, 97 staged PNL. The average operative time was (100 ± 50) minutes; the average intra-operative blood loss was (83 ± 67) ml. The stone clearance rate were 61.7% (3 days) and 79.5% (3 months). The postoperative hospital stay was (6.9 ± 3.4) days. A significantly higher ratio of multi-tract (χ(2) = 212.220, P < 0.01) and staged PNL (χ(2) = 49.679, P < 0.01), longer operative time (F = 4.652, P < 0.01) and postoperative hospital day (F = 2.067, P = 0.043) and lower rate of stone clearance (χ(2) = 10.691 and 47.369, P < 0.05) were found in PNL for calculi with stone branch number ≥ 5. There was no statistically meaningful difference among the 4 groups based on Clavien complication system (P = 0.460). The possibility of multi-tract and staged PNL, lower rate of stone clearance and longer postoperative hospital day increase for staghorn calculi with stone branch number more than 5.

Comparison of K-means and fuzzy c-means algorithm performance for automated determination of the arterial input function.

PubMed

Yin, Jiandong; Sun, Hongzan; Yang, Jiawen; Guo, Qiyong

2014-01-01

The arterial input function (AIF) plays a crucial role in the quantification of cerebral perfusion parameters. The traditional method for AIF detection is based on manual operation, which is time-consuming and subjective. Two automatic methods have been reported that are based on two frequently used clustering algorithms: fuzzy c-means (FCM) and K-means. However, it is still not clear which is better for AIF detection. Hence, we compared the performance of these two clustering methods using both simulated and clinical data. The results demonstrate that K-means analysis can yield more accurate and robust AIF results, although it takes longer to execute than the FCM method. We consider that this longer execution time is trivial relative to the total time required for image manipulation in a PACS setting, and is acceptable if an ideal AIF is obtained. Therefore, the K-means method is preferable to FCM in AIF detection.

Comparison of K-Means and Fuzzy c-Means Algorithm Performance for Automated Determination of the Arterial Input Function

PubMed Central

Yin, Jiandong; Sun, Hongzan; Yang, Jiawen; Guo, Qiyong

2014-01-01

The arterial input function (AIF) plays a crucial role in the quantification of cerebral perfusion parameters. The traditional method for AIF detection is based on manual operation, which is time-consuming and subjective. Two automatic methods have been reported that are based on two frequently used clustering algorithms: fuzzy c-means (FCM) and K-means. However, it is still not clear which is better for AIF detection. Hence, we compared the performance of these two clustering methods using both simulated and clinical data. The results demonstrate that K-means analysis can yield more accurate and robust AIF results, although it takes longer to execute than the FCM method. We consider that this longer execution time is trivial relative to the total time required for image manipulation in a PACS setting, and is acceptable if an ideal AIF is obtained. Therefore, the K-means method is preferable to FCM in AIF detection. PMID:24503700

Comparison of hatchet-shaped tensor fascia lata flap and pedicle anterior lateral thigh flap for treatment of trochanteric sores: a retrospective analysis of 48 patients.

PubMed

Li, Chun-Chang; Chang, Shun-Cheng; Fu, Ju-Peng; Tzeng, Yuan-Sheng; Wang, Chih-Hsing; Chen, Tim-Mo; Chen, Shyi-Gen

2013-12-01

Surgical reconstruction of trochanteric sores remains a formidable task for plastic surgeons. Diverse types of flaps have been proposed for use in this situation, each with particular advantages and limitations. This study aimed to compare the surgical outcomes between the hatchet-shaped tensor fascia lata (TFL) flap and the pedicle anterior lateral thigh (ALT) flap in treatment of trochanteric sores. Forty-eight patients with trochanteric sores were operated on under spinal or general anesthesia using TFL or ALT flaps between August 2007 and November 2010. In the TFL group, 26 hatchet-shaped TFL musculocutaneous flaps were performed on 24 patients. In the ALT group, 25 pedicle ALT musculocutaneous flaps were performed on 24 patients. Surgical outcomes were retrospectively analyzed. No significant difference was detected between the TFL and ALT groups in terms of age, preoperative disease period, obesity (body mass index), American Society of Anesthesiologists score, comorbidity, the defect size, follow-up time, and complication rate. The recurrence rate and the flap size were significantly higher in the TFL group than in the ALT group (P = 0.022; P < 0.001). The operation time was longer in the ALT group (P < 0.001). The pedicle ALT flap is a more effective treatment than the TFL flap for the surgical management of trochanteric sores. The hatchet-shaped TFL flap should be reserved for the reconstruction of recurrent trochanteric sores or for use in the critically ill patient who cannot tolerate longer anesthesia and operation time.

Lawn mower injuries in children: a 30-year experience.

PubMed

Nguyen, Anh; Raymond, Simon; Morgan, Vanessa; Peters, Julian; Macgill, Kirstie; Johnstone, Bruce

2008-09-01

Lawn mowers cause severe injuries that are particularly devastating to children. This study analyses the patterns and trends in lawn mower injuries involving children referred to Victoria's principal children's hospital. A retrospective review of the patient medical records at the Royal Children's Hospital (Melbourne) Victoria, Australia was carried out. The series included all patients admitted for lawn mower injury during the 30-year period spanning 1975-2004. Lawn mower injuries treated at Royal Children's Hospital were severe and included partially amputated limbs. Overall, admissions for lawn mower injury generally decreased over time from n = 26 in the 1975-1979 interval to n = 14 in the 2000-2004 interval. However, the frequency of admission for injuries caused by ride-on mowers contradicted the overall trend and generally increased over time from n = 5 in the 1975-1979 interval to n = 11 in the 2000-2004 interval. This is of particular concern. Ride-on lawn mowers caused significantly more severe injuries requiring longer periods of admission and more operations during admission in comparison to standard mowers. Rural location at the time of injury was a risk factor associated with requiring longer periods of admission and more operations during admission. Children injured while operating mowers were generally older than children injured as bystanders. Lawn mower injuries are a significant cause of morbidity. These injuries are particularly devastating to children. The tragedy is keenly felt in the realization that these devastating injuries to children could all be prevented. Strategic preventative measures should be developed through partnership between the medical profession, the media, industry specialists and the wider community.

The clinical research office of the endourological society percutaneous nephrolithotomy global study: staghorn versus nonstaghorn stones.

PubMed

Desai, Mahesh; De Lisa, Antonello; Turna, Burak; Rioja, Jorge; Walfridsson, Helena; D'Addessi, Alessandro; Wong, Carson; Rosette On Behalf Of The Croes Pcnl Study Group, Jean

2011-08-01

The study compared characteristics and outcomes in patients with staghorn or nonstaghorn stones who were treated with percutaneous nephrolithotomy (PCNL) within the Clinical Research Office of the Endourological Society (CROES) PCNL Global Study. Data over a 1-year period from consecutively treated patients from 96 centers worldwide were collated. The following variables in patients with staghorn or nonstaghorn stones were compared: National prevalence, patient characteristics, access method, puncture frequency and outcomes, including bleeding rates, operative time, and duration of hospital stay. Data from 5335 eligible patients were collated; 1466 (27.5%) with staghorn and 3869 (72.5%) with nonstaghorn stones. Staghorn stone presentation varied between centers from 67% in Thailand to 13% in Argentina. The frequencies of previous procedures were similar between groups, but shockwave lithotripsy was less frequent in patients with staghorn stones compared with nonstaghorn (16.8% vs 22.6%) and positive preoperative urine cultures were more frequent in patients with staghorn than nonstaghorn stones (23.4% vs 13.1%). Patients with staghorn stones underwent multiple punctures more frequently than those with nonstaghorn stones (16.9% vs 5.0%). Postoperative fever, bleeding, and the need for blood transfusion were more frequent, the median operative time and duration of hospital stay were longer, while the proportion of patients remaining stone free was lower (56.9% vs 82.5%) in patients with staghorn than nonstaghorn stones. The proportion of patients with staghorn stones varies widely between centers. Stone-free rates were lower, complications more frequent, and operative time and hospital stay were longer in patients with staghorn stones.

Single-port gynecologic surgery with a novel surgical platform.

PubMed

Knight, Jason; Tunitsky-Britton, Elena; Muffly, Tyler; Michener, Chad M; Escobar, Pedro F

2012-09-01

Laparoendoscopic single-site surgery (LESS) allows better cosmesis and decreased pain when compared with traditional laparoscopy (TL). Instrument crowding and diminished triangulation are limitations. This study evaluates a novel single-port surgical platform (NSP) designed to facilitate the transition from TL to LESS (TransEnterix SPIDER, Durham, NC). NSP and TL were compared using standardized dry lab tasks. Feasibility of NSP in gynecology was assessed using the porcine model. Completion times with NSP were longer for ring transfer (P = .025) and trended longer for disc cutting (P = .074). Disc cutting accuracy was lower with NSP versus TL (P = .008). NSP operative times for hysterectomy, pelvic and para-aortic node dissection were 22.3, 13.3, and 26 minutes, respectively, without complications. Fatigue and lack of integrated bipolar cautery were limitations of NSP. While application of NSP to gynecology appears feasible, lower performance when compared with TL underscores the need for caution when applying NSP to humans.

Early assessment of bilateral inguinal hernia repair: A comparison between the laparoscopic total extraperitoneal and Stoppa approaches.

PubMed

Utiyama, Edivaldo Massazo; Damous, S Rgio Henrique Bastos; Tanaka, Eduardo Yassushi; Yoo, Jin Hwan; de Miranda, Jocielle Santos; Ushinohama, Adriano Zuardi; Faro, Mario Paulo; Birolini, Claudio Augusto Vianna

2016-01-01

The present clinical trial was designed to compare the results of bilateral inguinal hernia repair between patients who underwent the conventional Stoppa technique and laparoscopic total extraperitoneal repair (LTE) with a single mesh and without staple fixation. This controlled, randomised clinical trial was conducted at General Surgery and Trauma of the Clinics Hospital, Medical School, the University of São Paulo between September 2010 and February 2011. Totally, 50 male patients, with a bilateral inguinal hernia, older than 25 years were considered eligible for the study. The following parameters were analysed during the early post-operative period: (1) The intensity of surgical trauma, operation time, C-reactive protein (CRP) levels, white blood cell count, bleeding and pain intensity; (2) quality of life assessment; and (3) post-operative complications. LTE procedure was longer than the Stoppa procedure (134.6 min ± 38.3 vs. 90.6 min ± 41.3; P < 0.05). The levels of CRP were higher in the Stoppa group (P < 0.05) but the number of leucocytes, haematocrit, and haemoglobin were similar between the groups (P > 0.05). There was no difference in pain during the 1st and 7th post-operative, physical functioning, physical limitation, the impact of pain on daily activities, and the Carolinas Comfort Scale during the 7th and 15th post-operative (P > 0.05). Complications occurred in 88% of Stoppa group (22 patients) and 64% in LTE group (16 patients) (P < 0.05). The comparative study between the Stoppa and LTE approaches for the bilateral inguinal hernia repair demonstrated that: (1) The LTE approach showed less surgical trauma despite the longer operation time; (2) Quality of life during the early post-operative period were similar; and (3) Complication rates were higher in the Stoppa group.

Operating room-to-incision interval and neonatal outcome in emergency caesarean section: a retrospective 5-year cohort study.

PubMed

Palmer, E; Ciechanowicz, S; Reeve, A; Harris, S; Wong, D J N; Sultan, P

2018-07-01

We conducted a 5-year retrospective cohort study on women undergoing caesarean section to investigate factors influencing the operating room-to-incision interval. Time-to-event analysis was performed for category-1 caesarean section using a Cox proportional hazards regression model. Covariates included: anaesthetic technique; body mass index; age; parity; time of delivery; and gestational age. Binary logistic regression was performed for 5-min Apgar score ≥ 7. There were 677 women who underwent category-1 caesarean section and who met the entry criteria. Unadjusted median (IQR [range]) operating room-to-incision intervals were: epidural top-up 11 (7-17 [0-87]) min; general anaesthesia 6 (4-11 [0-69]) min; spinal 13 (10-20 [0-83]) min; and combined spinal-epidural 24 (13-35 [0-75]) min. Cox regression showed general anaesthesia to be the most rapid method with a hazard ratio (95%CI) of 1.97 (1.60-2.44; p < 0.0001), followed by epidural top-up (reference group), spinal anaesthesia 0.79 (0.65-0.96; p = 0.02) and combined spinal-epidural 0.48 (0.35-0.67; p < 0.0001). Underweight and overweight body mass indexes were associated with longer operating room-to-incision intervals. General anaesthesia was associated with fewer 5-min Apgar scores ≥ 7 with an odds ratio (95%CI) of 0.28 (0.11-0.68; p < 0.01). There was no difference in neonatal outcomes between the first and fifth quintiles for operating room-to-incision intervals. General anaesthesia is associated with the most rapid operating room-to-incision interval for category-1 caesarean section, but is also associated with worse short term neonatal outcomes. Longer operating room-to-incision intervals were not associated with worse neonatal outcomes. © 2018 The Association of Anaesthetists of Great Britain and Ireland.

Early assessment of bilateral inguinal hernia repair: A comparison between the laparoscopic total extraperitoneal and Stoppa approaches

PubMed Central

Utiyama, Edivaldo Massazo; Damous, Sérgio Henrique Bastos; Tanaka, Eduardo Yassushi; Yoo, Jin Hwan; de Miranda, Jocielle Santos; Ushinohama, Adriano Zuardi; Faro, Mario Paulo; Birolini, Claudio Augusto Vianna

2016-01-01

BACKGROUND: The present clinical trial was designed to compare the results of bilateral inguinal hernia repair between patients who underwent the conventional Stoppa technique and laparoscopic total extraperitoneal repair (LTE) with a single mesh and without staple fixation. PATIENTS AND METHODS: This controlled, randomised clinical trial was conducted at General Surgery and Trauma of the Clinics Hospital, Medical School, the University of São Paulo between September 2010 and February 2011. Totally, 50 male patients, with a bilateral inguinal hernia, older than 25 years were considered eligible for the study. The following parameters were analysed during the early post-operative period: (1) The intensity of surgical trauma, operation time, C-reactive protein (CRP) levels, white blood cell count, bleeding and pain intensity; (2) quality of life assessment; and (3) post-operative complications. RESULTS: LTE procedure was longer than the Stoppa procedure (134.6 min ± 38.3 vs. 90.6 min ± 41.3; P < 0.05). The levels of CRP were higher in the Stoppa group (P < 0.05) but the number of leucocytes, haematocrit, and haemoglobin were similar between the groups (P > 0.05). There was no difference in pain during the 1st and 7th post-operative, physical functioning, physical limitation, the impact of pain on daily activities, and the Carolinas Comfort Scale during the 7th and 15th post-operative (P > 0.05). Complications occurred in 88% of Stoppa group (22 patients) and 64% in LTE group (16 patients) (P < 0.05). CONCLUSION: The comparative study between the Stoppa and LTE approaches for the bilateral inguinal hernia repair demonstrated that: (1) The LTE approach showed less surgical trauma despite the longer operation time; (2) Quality of life during the early post-operative period were similar; and (3) Complication rates were higher in the Stoppa group. PMID:27279401

Community-based evaluation of laparoscopic versus open simple closure of perforated peptic ulcers.

PubMed

Kuwabara, Kazuaki; Matsuda, Shinya; Fushimi, Kiyohide; Ishikawa, Koichi B; Horiguchi, Hiromasa; Fujimori, Kenji

2011-11-01

Several studies have advocated laparoscopic simple closure (LSC) as the treatment of choice for perforated peptic ulcer disease (PUD). However, there has been no comprehensive community-based evaluation of the advantages of using LSC over open simple closure (OSC). Using an administrative database, we evaluated LSC versus OSC for patients with perforated ulcers. From 6,334 patients with perforated ulcers, we identified 2,909 simple closure cases between 2006 and 2010. Study variables were demographics, mortality, co-morbidities, complications, ulcer location, surgical timing, blood transfusion, postoperative ventilation, operating room (OR) time, time to resumption of oral food intake, length of stay (LOS), and total charges. After matching patient baseline variables between OSC and LSC, we performed multivariate analyses to assess the impacts of LSC on mortality, complications, and ventilation administration. A total of 2,073 OSC cases and 836 LSC cases were identified in 670 hospitals. Younger age, duodenal ulcer, and pre-existing PUD were indicators for selection of LSC. Matching analysis indicated a correlation between LSC and lower mortality, less frequent postoperative and overall blood transfusion, shorter LOS, earlier return to oral intake, and longer OR time. There was no difference between OSC and LSC in complication rate or mortality. Longer OR time was correlated with a higher complication rate and the need for ventilation, the latter of which was independently associated with an increase in mortality. Because longer OR time was associated with more frequent complications and ventilation, surgeons should obtain the skills and strategies necessary to accomplish LSC without extending OR time improperly.

The influence of the different forms of appendix base closure on patient outcome in laparoscopic appendectomy: a randomized trial.

PubMed

Delibegović, Samir; Mehmedovic, Zlatan

2018-05-01

During laparoscopic appendectomy, the base of the appendix is usually secured by loop ligature or stapling device. Hem-o-lok and DS clips have been shown as alternative techniques. The aim of this study was to compare the clinical outcomes of various forms of securing the base of the appendix, in order to find the most suitable method. The study included 120 patients with acute appendicitis randomly divided into four groups with 30 patients in each. In the first group, the base of the appendix was secured using an Endoloop, in the second group using a stapling device, in the third group using Hem-o-lok, and in the fourth group using a DS clip. The primary outcome was overall morbidity following securing the base of the appendix. Secondary outcomes were time of application and operative procedure, total length of stay, and surgical outcome. No morbidity was recorded in any group. The time of application was significantly longer in the Endoloop group than in the Stapler (P < 0.0001), Hem-o-lok (P < 0.0001), and DS clips (P < 0.0001) groups. The time of application in the Stapler group was significantly shorter than in the Hem-o-lok (P < 0.0001) and the DS clips (P < 0.0001) groups. The time of the operative procedure was significantly longer in the Endoloop than in the Stapler group (P < 0.0001). The time of the operative procedure in the Stapler group was significantly shorter than in the DS clips group (P < 0.0001) but did not differ significantly from the Hem-o-lok group (P = 0.199). The time of the operative procedure in the Hem-o-lok group was significantly shorter than in the DS clips group (P = 0.044). All forms of closure of the appendix base are acceptable, but Hem-o-lok and DS clips have the best potential for further development, and will probably become the method of choice in securing the base of the appendix.

A comparison of robotic single-incision and traditional single-incision laparoscopic cholecystectomy.

PubMed

Gustafson, Monica; Lescouflair, Tariq; Kimball, Randall; Daoud, Ibrahim

2016-06-01

Surgeons continually strive to improve technology and patient care. One remarkable demonstration of this is the development of laparoscopic surgery. Once this proved to be a safe and reliable surgical approach, robotics seemed a logical progression of surgical technology. The aim of this project was to evaluate the utility of robotics in the context of single-incision laparoscopic cholecystectomy (SILC). A retrospective review of a prospectively maintained database of robotic single-incision laparoscopic cholecystectomy (RSILC) and traditional SILC performed by a single surgeon at our institution from July 2010 to August 2013 was queried. All consecutive patients undergoing RSILC and SILC during this time period were included. Primary outcomes include conversion rate and operative time. Secondary outcomes include length of stay, duration of narcotic use, time to independent performance of daily activities and cost. Categorical variables were evaluated using Chi-square analysis and continuous variables using t test or Wilcoxon's rank test. Thirty-eight patients underwent RSILC and 44 underwent SILC. BMI was higher in the RSILC group, and the number of patients with prior abdominal surgeries was higher in the SILC group. Otherwise, demographics were similar between the two groups. There was no difference in conversion rate between RSILC and SILC (8 vs 11 %, p = 0.60). Mean operative time for RSILC was significantly greater compared with SILC (98 vs 68 min, p < 0.0001). RSILC was associated with a longer duration of narcotic use (2.3 vs 1.7 days, p = 0.0019) and time to independent performance of daily activities (4 vs 2.3 days, p < 0.0001). Total cost is greater in RSILC ($8961 vs $5379, p < 0.0001). While RSILC can be safely performed, it is associated with longer operative times and greater cost.

[Gender and age differences in waiting time on hospital waiting list.].

PubMed

Thornórðardóttir, Steinunn; Halldórsson, Matthías; Guðmundsson, Sigurður

2002-09-01

The size of waiting lists has traditionally been viewed as a fairly good measure of the quality of health care services. No statistical analysis exists in Iceland of the length of waiting times and the potential variation between groups of patients. This study was conducted within the office of the Directorate of Health in Iceland. This location was convenient since standardized information on waiting lists is collected by the office three times a year. Variations in waiting times were studied based on gender on the one hand and on age on the other. Data from the largest waiting lists, those amounting to 400 or more patients, were included in the study. The most frequently awaited operations were identified and the groups of people waiting for them analyzed. The departments and prospective operations included in the study were: Dept. of General Surgery at the University Hospital (UH) (laparoscopic gastro-oesophageal antireflux operation), Opthalmology at UH (phakoemulsification with implantation of artificial lens in posterior chamber), Orthopedic Surgery at UH (primary total prosthetic replacement of hip joint using sement), The Rehabilitation Center at Reykjalundur (rehabilitation, not specified), Ear, Nose and Throat (ENT) at UH (tonsillectomy), and Reconstructive Surgery at UH (reduction mammoplasty with transposition of areola). The lists were sorted by gender and age, with the latter consisting of two categories, older and younger patients. Every attempt was made as to ensure similar sample sizes for both age groups within each department. Finally, the median waiting time was determined and a Mann-Whitney test conducted in order to test for significance. The median waiting time for males at the General Surgery Dept. was 73 weeks as compared to 60 weeks for females. This was the only department where the median waiting time was significantly longer for males than for females (p<0.05). At three of the departments the older group had a longer median waiting time than the younger group, 18 weeks compared to 14 at Opthalmology (p<0.001), 26 versus 17 weeks at Reykjalundur (p<0.025) and 33 versus 21 weeks at ENT (p<0.01). Waiting times for females was significantly longer than for males at two departments, Reykjalundur (21 vs. 17 weeks, p<0.05) and ENT (33 vs. 29 weeks, p<0.05). This study revealed age and gender differences in median waiting times at Icelandic hospitals. These differences were in many cases marked and statistically significant. Various explanations have been put forward, however, further research is needed in order to determine if it these differences are due to actual clinical needs assessments or to age or gender discrimination.

[Influencing factors on surgical duration of ovarian cystectomy by single-port access].

PubMed

Poizac, S; Ménager, N; Tourette, C; Gnisci, A; Estrade, J-P; Agostini, A

2015-01-01

To evaluate the factors influencing the operative duration of ovarian cystectomy by single-port access (SPA). Observational monocentric study from June 2010 to September 2012. Inclusive patients were patients with an indication of ovarian cystectomy may be done by laparoscopy. The procedures were performed by the SPA system LESS®. Factors evaluated were BMI of the patient, histological nature and size of the cyst. We performed 54 cystectomy in 49 patients. SPA surgery was successfully completed in 53 patients. The median operative time was statistically longer for endometriotic cysts than dermoid cysts or serous-mucinous cysts (P=0.003). Cases exceeding 60minutes were significantly higher in the endometriosis group (P=0.005). There wasn't correlation found between the BMI of the patient and operative time (P=0.5). The operating time wasn't increased according to the size of the cyst (P=0.9). Endometriotic cysts nature appears to be the only limiting factor of cystectomy by SPA. Further studies are needed to evaluate the factors that may limit the SPA actions. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

42 CFR 424.535 - Revocation of enrollment and billing privileges in the Medicare program.

Code of Federal Regulations, 2010 CFR

2010-10-01

... application applicable for its provider or supplier type, and has not submitted a plan of corrective action as... supplier is no longer operational to furnish Medicare covered items or services, or is not meeting Medicare... A provider is no longer operational to furnish Medicare covered items or services, or the provider...

Temporal ventriloquism: crossmodal interaction on the time dimension. 1. Evidence from auditory-visual temporal order judgment.

PubMed

Bertelson, Paul; Aschersleben, Gisa

2003-10-01

In the well-known visual bias of auditory location (alias the ventriloquist effect), auditory and visual events presented in separate locations appear closer together, provided the presentations are synchronized. Here, we consider the possibility of the converse phenomenon: crossmodal attraction on the time dimension conditional on spatial proximity. Participants judged the order of occurrence of sound bursts and light flashes, respectively, separated in time by varying stimulus onset asynchronies (SOAs) and delivered either in the same or in different locations. Presentation was organized using randomly mixed psychophysical staircases, by which the SOA was reduced progressively until a point of uncertainty was reached. This point was reached at longer SOAs with the sounds in the same frontal location as the flashes than in different places, showing that apparent temporal separation is effectively longer in the first condition. Together with a similar one obtained recently in a case of tactile-visual discrepancy, this result supports a view in which timing and spatial layout of the inputs play to some extent inter-changeable roles in the pairing operation at the base of crossmodal interaction.

Kraus Operators for a Pair of Interacting Qubits: a Case Study

NASA Astrophysics Data System (ADS)

Arsenijević, M.; Jeknić-Dugić, J.; Dugić, M.

2018-04-01

The Kraus form of the completely positive dynamical maps is appealing from the mathematical and the point of the diverse applications of the open quantum systems theory. Unfortunately, the Kraus operators are poorly known for the two-qubit processes. In this paper, we derive the Kraus operators for a pair of interacting qubits, while the strength of the interaction is arbitrary. One of the qubits is subjected to the x-projection spin measurement. The obtained results are applied to calculate the dynamics of the entanglement in the qubits system. We obtain the loss of the correlations in the finite time interval; the stronger the inter-qubit interaction, the longer lasting entanglement in the system.

Visual discrimination in an orangutan (Pongo pygmaeus): measuring visual preference.

PubMed

Hanazuka, Yuki; Kurotori, Hidetoshi; Shimizu, Mika; Midorikawa, Akira

2012-04-01

Although previous studies have confirmed that trained orangutans visually discriminate between mammals and artificial objects, whether orangutans without operant conditioning can discriminate remains unknown. The visual discrimination ability in an orangutan (Pongo pygmaeus) with no experience in operant learning was examined using measures of visual preference. Sixteen color photographs of inanimate objects and of mammals with four legs were randomly presented to an orangutan. The results showed that the mean looking time at photographs of mammals with four legs was longer than that for inanimate objects, suggesting that the orangutan discriminated mammals with four legs from inanimate objects. The results implied that orangutans who have not experienced operant conditioning may possess the ability to discriminate visually.

Kraus Operators for a Pair of Interacting Qubits: a Case Study

NASA Astrophysics Data System (ADS)

Arsenijević, M.; Jeknić-Dugić, J.; Dugić, M.

2018-06-01

The Kraus form of the completely positive dynamical maps is appealing from the mathematical and the point of the diverse applications of the open quantum systems theory. Unfortunately, the Kraus operators are poorly known for the two-qubit processes. In this paper, we derive the Kraus operators for a pair of interacting qubits, while the strength of the interaction is arbitrary. One of the qubits is subjected to the x-projection spin measurement. The obtained results are applied to calculate the dynamics of the entanglement in the qubits system. We obtain the loss of the correlations in the finite time interval; the stronger the inter-qubit interaction, the longer lasting entanglement in the system.

Totally laparoscopic radical BII gastrectomy for the treatment of gastric cancer: a comparison with open surgery.

PubMed

Lee, Wei-Jei; Wang, Weu; Chen, Tai-Chi; Chen, Jung-Chieh; Ser, Kong-Han

2008-08-01

Laparoscopically assisted distal gastrectomy has been used for distal part early gastric cancer resection. However, use of totally laparoscopic gastric cancer resection remains limited because of technical problems, especially when standard D2 nodal dissection was applied. We had reported the first totally laparoscopic Billroth II (BII) subtotal gastrectomy with lymphadenectomy for early gastric cancer in the year 1998. The aim of this study is to determine whether this procedure is superior to conventional open technique. The clinical course of 34 consecutive patients who underwent totally laparoscopic BII gastrectomy using an upper to lower, right to left, and clockwise quadrant-to-quadrant technique was compared with 34 sex-matched and age-matched patients who underwent open gastrectomy. Main outcome measures included operative time, blood loss, length of stay, morbidity and mortality, adequacy of lymphadenectomy, and long-term outcome. In the laparoscopic group, all the operations were completed by laparoscopic technique, but 1 patient required secondary laparotomy for total gastrectomy owing to inadequate resection margin. There was no operation mortality in this study. The postoperative complication rates were similar in these 2 groups. The mean operative time for laparoscopic group was 283+/-122 minutes (range: 186 to 480 min), significantly longer than the 195+/-26 minutes in the conventional group (P<0.001). Laparoscopic group was associated with less intraoperative blood loss (74 vs. 190 mL; P<0.01), early flatus passage (2.9 vs. 4.9 d; P<0.01), less usage of analgesics (3.5 vs. 5.8 doses; P<0.05), and a shorter postoperative hospital stay (8.5 vs. 12.1 d; P<0.01). There was no significant difference between laparoscopic and conventional open radical gastrectomy with regard to ratio of free margin, number of harvested lymph nodes, and survival. Although totally laparoscopic BII gastrectomy using the upper to lower technique required a longer surgical time and was technically more demanding than conventional open surgery, it resulted in shorter recovery time, less analgesic use, and less severe physical discomfort without compromising the operative curability and oncologic outcomes.

Spinal pedicle subtraction osteotomy for fixed sagittal imbalance patients

PubMed Central

Hyun, Seung-Jae; Kim, Yongjung J; Rhim, Seung-Chul

2013-01-01

In addressing spinal sagittal imbalance through a posterior approach, the surgeon now may choose from among a variety of osteotomy techniques. Posterior column osteotomies such as the facetectomy or Ponte or Smith-Petersen osteotomy provide the least correction, but can be used at multiple levels with minimal blood loss and a lower operative risk. Pedicle subtraction osteotomies provide nearly 3 times the per-level correction of Ponte/Smith-Petersen osteotomies; however, they carry increased technical demands, longer operative time, and greater blood loss and associated significant morbidity, including neurological injury. The literature focusing on pedicle subtraction osteotomy for fixed sagittal imbalance patients is reviewed. The long-term overall outcomes, surgical tips to reduce the complications and suggestions for their proper application are also provided. PMID:24340276

Combined Characterization of the Time Response of Impression Materials via Traditional and FTIR Measurements

PubMed Central

Derchi, Giacomo; Manca, Enrico; Shayganpour, Amirreza; Barone, Antonio; Diaspro, Alberto; Salerno, Marco

2015-01-01

We investigated the temporal response of four dental impression materials, namely three siloxanes (Imprint 4, Flexitime, Aquasil) and one polyether (Impregum). The null hypothesis was that the nominal working times are confirmed by instrumental laboratory tests. We also aimed to identify alternative techniques with strong physical-chemical background for the assessment of temporal response. Traditional characterization was carried out by shark fin test device and durometer at both ambient and body temperature. Additionally, Fourier-transform infrared spectroscopy was performed at room temperature. From shark fin height and Shore hardness versus time the working time and the setting time of the materials were evaluated, respectively. These were in reasonable agreement with the nominal values, except for Impregum, which showed longer working time. Spectroscopy confirmed the different character of the two types of materials, and provided for Imprint 4 and Aquasil an independent evaluation of both evolution times, consistent with the results of the other techniques. Shark fin test and durometer measurements showed deviations in setting time, low sensitivity to temperature for Flexitime, and longer working time at higher temperature for Impregum. Deviations of working time appear in operating conditions from what specified by the manufacturers. Fourier-transform infrared spectroscopy can provide insight in the correlation between material properties and their composition and structure.

Temporal Simultons in Optical Parametric Oscillators

NASA Astrophysics Data System (ADS)

Jankowski, Marc; Marandi, Alireza; Phillips, C. R.; Hamerly, Ryan; Ingold, Kirk A.; Byer, Robert L.; Fejer, M. M.

2018-02-01

We report the first demonstration of a regime of operation in optical parametric oscillators (OPOs), in which the formation of temporal simultons produces stable femtosecond half-harmonic pulses. Simultons are simultaneous bright-dark solitons of a signal field at frequency ω and the pump field at 2 ω , which form in a quadratic nonlinear medium. The formation of simultons in an OPO is due to the interplay of nonlinear pulse acceleration with the timing mismatch between the pump repetition period and the cold-cavity round-trip time and is evidenced by sech2 spectra with broad instantaneous bandwidths when the resonator is detuned to a slightly longer round-trip time than the pump repetition period. We provide a theoretical description of an OPO operating in a regime dominated by these dynamics, observe the distinct features of simulton formation in an experiment, and verify our results with numerical simulations. These results represent a new regime of operation in nonlinear resonators, which can lead to efficient and scalable sources of few-cycle frequency combs at arbitrary wavelengths.

Predictors of short-term and long-term incontinence after robot-assisted radical prostatectomy.

PubMed

Shao, I-Hung; Chang, Ying-Hsu; Hou, Chun-Ming; Lin, Zheng-Feng; Wu, Chun-Te

2018-01-01

Purpose To determine retrospectively the prognostic factors for urinary incontinence following robot-assisted radical prostatectomy (RARP). Methods Altogether, 180 patients with localized prostate cancer underwent RARP (same surgeon). Preoperative physical status, disease characteristics, laboratory findings, and surgical technique were recorded and the patients checked 1, 6, 12, and 24 months after RARP regarding their contribution to predicting post-prostatectomy urinary incontinence (PPI). Results Overall, 114 (63.3%) patients had PPI 1 month after RARP and 19 patients (16.0%) at 24 months. Univariate analysis showed that age was a significant factor for predicting PPI at 1 month. PPI predictors at 24 months were age, body mass index, preoperative serum albumin level, previous transurethral resection of the prostate, total operative time, and bladder neck sparing. Multivariate analysis indicated that age and total operative time were significant predictors. Conclusion Older age and longer operative time were highly relevant to short- and long-term PPI occurrence after RARP.

Effects of operational conditions on sludge degradation and organic acids formation in low-critical wet air oxidation.

PubMed

Chung, Jinwook; Lee, Mikyung; Ahn, Jaehwan; Bae, Wookeun; Lee, Yong-Woo; Shim, Hojae

2009-02-15

Wet air oxidation processes are to treat highly concentrated organic compounds including refractory materials, sludge, and night soil, and usually operated at supercritical water conditions of high temperature and pressure. In this study, the effects of operational conditions including temperature, pressure, and oxidant dose on sludge degradation and conversion into subsequent intermediates such as organic acids were investigated at low critical wet oxidation conditions. The reaction time and temperature in the wet air oxidation process was shown an important factor affecting the liquefaction of volatile solids, with more significant effect on the thermal hydrolysis reaction rather than the oxidation reaction. The degradation efficiency of sludge and the formation of organic acids were improved with longer reaction time and higher reaction temperature. For the sludge reduction and the organic acids formation under the wet air oxidation, the optimal conditions for reaction temperature, time, pressure, and oxidant dose were shown approximately 240 degrees C, 30min, 60atm, and 2.0L/min, respectively.

Sensitivity of chemical transport model simulations to the duration of chemical and transport operators: a case study with GEOS-Chem v10-01

NASA Astrophysics Data System (ADS)

Philip, S.; Martin, R. V.; Keller, C. A.

2015-11-01

Chemical transport models involve considerable computational expense. Fine temporal resolution offers accuracy at the expense of computation time. Assessment is needed of the sensitivity of simulation accuracy to the duration of chemical and transport operators. We conduct a series of simulations with the GEOS-Chem chemical transport model at different temporal and spatial resolutions to examine the sensitivity of simulated atmospheric composition to temporal resolution. Subsequently, we compare the tracers simulated with operator durations from 10 to 60 min as typically used by global chemical transport models, and identify the timesteps that optimize both computational expense and simulation accuracy. We found that longer transport timesteps increase concentrations of emitted species such as nitrogen oxides and carbon monoxide since a more homogeneous distribution reduces loss through chemical reactions and dry deposition. The increased concentrations of ozone precursors increase ozone production at longer transport timesteps. Longer chemical timesteps decrease sulfate and ammonium but increase nitrate due to feedbacks with in-cloud sulfur dioxide oxidation and aerosol thermodynamics. The simulation duration decreases by an order of magnitude from fine (5 min) to coarse (60 min) temporal resolution. We assess the change in simulation accuracy with resolution by comparing the root mean square difference in ground-level concentrations of nitrogen oxides, ozone, carbon monoxide and secondary inorganic aerosols with a finer temporal or spatial resolution taken as truth. Simulation error for these species increases by more than a factor of 5 from the shortest (5 min) to longest (60 min) temporal resolution. Chemical timesteps twice that of the transport timestep offer more simulation accuracy per unit computation. However, simulation error from coarser spatial resolution generally exceeds that from longer timesteps; e.g. degrading from 2° × 2.5° to 4° × 5° increases error by an order of magnitude. We recommend prioritizing fine spatial resolution before considering different temporal resolutions in offline chemical transport models. We encourage the chemical transport model users to specify in publications the durations of operators due to their effects on simulation accuracy.

Civil helicopter propulsion system reliability and engine monitoring technology assessments

NASA Technical Reports Server (NTRS)

Murphy, J. A.; Zuk, J.

1982-01-01

A study to reduce operating costs of helicopters, particularly directed at the maintenance of the propulsion subsystem, is presented. The tasks of the study consisted of problem definition refinement, technology solutions, diagnostic system concepts, and emergency power augmentation. Quantifiable benefits (reduced fuel consumption, on-condition engine maintenance, extended drive system overhaul periods, and longer oil change intervals) would increase the initial cost by $43,000, but the benefit of $24.46 per hour would result in breakeven at 1758 hours. Other benefits not capable of being quantified but perhaps more important include improved aircraft avilability due to reduced maintenance time, potential for increased operating limits due to continuous automatic monitoring of gages, and less time and fuel required to make engine power checks. The most important improvement is the on-condition maintenance program, which will require the development of algorithms, equipment, and procedures compatible with all operating environments.

Oxygen Toxicity and Special Operations Forces Diving: Hidden and Dangerous

PubMed Central

Wingelaar, Thijs T.; van Ooij, Pieter-Jan A. M.; van Hulst, Rob A.

2017-01-01

In Special Operations Forces (SOF) closed-circuit rebreathers with 100% oxygen are commonly utilized for covert diving operations. Exposure to high partial pressures of oxygen (PO2) could cause damage to the central nervous system (CNS) and pulmonary system. Longer exposure time and higher PO2 leads to faster development of more serious pathology. Exposure to a PO2 above 1.4 ATA can cause CNS toxicity, leading to a wide range of neurologic complaints including convulsions. Pulmonary oxygen toxicity develops over time when exposed to a PO2 above 0.5 ATA and can lead to inflammation and fibrosis of lung tissue. Oxygen can also be toxic for the ocular system and may have systemic effects on the inflammatory system. Moreover, some of the effects of oxygen toxicity are irreversible. This paper describes the pathophysiology, epidemiology, signs and symptoms, risk factors and prediction models of oxygen toxicity, and their limitations on SOF diving. PMID:28790955

Orbit Stability of OSIRIS-REx in the Vicinity of Bennu Using a High-Fidelity Solar Radiation Model

NASA Technical Reports Server (NTRS)

Williams, Trevor; Hughes, Kyle; Mashiku, Alinda; Longuski, James

2015-01-01

The OSIRIS-REx mission (Origins Spectral Interpretation Resource Identification Security Regolith EXPlorer) is an asteroid sample return mission to Bennu (RQ36) that is scheduled to launch in 2016. The planned science operations precluding the small retrieval involve operations in terminator orbits (orbit plane is perpendicular to the sun). Over longer durations the solar radiation pressure (SRP) perturbs the orbit causing it to precess. Our work involves: modeling high fidelity SRP model to capture the perturbations during attitude changes; design a stable orbit from the high fidelity models to analyze the stability over time.

Examination of Daily Weather in the NCAR CCM

NASA Astrophysics Data System (ADS)

Cocke, S. D.

2006-05-01

The NCAR CCM is one of the most extensively studied climate models in the scientific community. However, most studies focus primarily on the long term mean behavior, typically monthly or longer time scales. In this study we examine the daily weather in the GCM by performing a series of daily or weekly 10 day forecasts for one year at moderate (T63) and high (T126) resolution. The model is initialized with operational "AVN" and ECMWF analyses, and model performance is compared to that of major operational centers, using conventional skill scores used by the major centers. Such a detailed look at the CCM at shorter time scales may lead to improvements in physical parameterizations, which may in turn lead to improved climate simulations. One finding from this study is that the CCM has a significant drying tendency in the lower troposphere compared to the operational analyses. Another is that the large scale predictability of the GCM is competitive with most of the operational models, particularly in the southern hemisphere.

Effect of facility on the operative costs of distal radius fractures.

PubMed

Mather, Richard C; Wysocki, Robert W; Mack Aldridge, J; Pietrobon, Ricardo; Nunley, James A

2011-07-01

The purpose of this study was to investigate whether ambulatory surgery centers can deliver lower-cost care and to identify sources of those cost savings. We performed a cost identification analysis of outpatient volar plating for closed distal radius fractures at a single academic medical center. Multiple costs and time measures were taken from an internal database of 130 consecutive patients and were compared by venue of treatment, either an inpatient facility or an ambulatory, stand-alone surgery facility. The relationships between total cost and operative time and multiple variables, including fracture severity, patient age, gender, comorbidities, use of bone graft, concurrent carpal tunnel release, and surgeon experience, were examined, using multivariate analysis and regression modeling to identify other cost drivers or explanatory variables. The mean operative cost was considerably greater at the inpatient facility ($7,640) than at the outpatient facility ($5,220). Cost drivers of this difference were anesthesia services, post-anesthesia care unit, and operating room costs. Total surgical time, nursing time, set-up, and operative times were 33%, 109%, 105%, and 35% longer, respectively, at the inpatient facility. There was no significant difference between facilities for the additional variables, and none of those variables independently affected cost or operative time. The only predictor of cost and time was facility type. This study supports the use of ambulatory stand-alone surgical facilities to achieve efficient resource utilization in the operative treatment of distal radius fractures. We also identified several specific costs and time measurements that differed between facilities, which can serve as potential targets for tertiary facilities to improve utilization. Economic and Decisional Analysis III. Copyright © 2011 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Concomitant management of renal calculi and pelvi-ureteric junction obstruction with robotic laparoscopic surgery.

PubMed

Atug, Fatih; Castle, Erik P; Burgess, Scott V; Thomas, Raju

2005-12-01

To present technical recommendations for robotic-assisted laparoscopic pyeloplasty (RALP) and stone extraction, as patients with kidney stones proximal to a pelvi-ureteric junction obstruction (PUJO) present a technical challenge, and have traditionally been managed with open surgery or percutaneous antegrade endopyelotomy. From November 2002 to April 2005, 55 patients had RALP for PUJO; eight of these had concomitant renal calculi. Stone burden and location were assessed with a preoperative radiological examination. Before completing the PUJO repair, one robot working arm (cephalad one) was temporarily undocked to allow passage of a flexible nephroscope into the renal pelvis and collecting systems under direct vision. Stones were extracted with graspers or basket catheters and removed via the port. The surgical-assistant port in the subxiphoid area was used to introduce laparoscopic suction and other instruments. The Anderson-Hynes dismembered pyeloplasty was the preferred reconstructive technique in all patients. Operations were completed robotically with no conversions to open surgery. All patients were rendered stone-free, confirmed by imaging, and there were no intraoperative or delayed complications during a mean (range) follow-up of 12.3 (4-22) months. The mean operative time was 275.8 min, 61.7 min longer than in patients who did not have concomitant stone removal. Concurrent stone extraction and PUJO repair can be successful with RALP. Operative times are longer than in patients with isolated PUJO repair, but this is to be expected as there is an additional procedure.

Self-efficacy pathways to childhood depression.

PubMed

Bandura, A; Pastorelli, C; Barbaranelli, C; Caprara, G V

1999-02-01

This prospective research analyzed how different facets of perceived self-efficacy operate in concert within a network of sociocognitive influences in childhood depression. Perceived social and academic inefficacy contributed to concurrent and subsequent depression both directly and through their impact on academic achievement, prosocialness, and problem behaviors. In the shorter run, children were depressed over beliefs in their academic inefficacy rather than over their actual academic performances. In the longer run, the impact of a low sense of academic efficacy on depression was mediated through academic achievement, problem behavior, and prior depression. Perceived social inefficacy had a heavier impact on depression in girls than in boys in the longer term. Depression was also more strongly linked over time for girls than for boys.

10 CFR 40.2a - Coverage of inactive tailings sites.

Code of Federal Regulations, 2011 CFR

2011-01-01

... materials as defined in this part that are located at a site where milling operations are no longer active... defined in this part that is located at a site where milling operations are no longer active, if such site... 10 Energy 1 2011-01-01 2011-01-01 false Coverage of inactive tailings sites. 40.2a Section 40.2a...

10 CFR 40.2a - Coverage of inactive tailings sites.

Code of Federal Regulations, 2012 CFR

2012-01-01

... materials as defined in this part that are located at a site where milling operations are no longer active... defined in this part that is located at a site where milling operations are no longer active, if such site... 10 Energy 1 2012-01-01 2012-01-01 false Coverage of inactive tailings sites. 40.2a Section 40.2a...

10 CFR 40.2a - Coverage of inactive tailings sites.

Code of Federal Regulations, 2014 CFR

2014-01-01

... materials as defined in this part that are located at a site where milling operations are no longer active... defined in this part that is located at a site where milling operations are no longer active, if such site... 10 Energy 1 2014-01-01 2014-01-01 false Coverage of inactive tailings sites. 40.2a Section 40.2a...

10 CFR 40.2a - Coverage of inactive tailings sites.

Code of Federal Regulations, 2013 CFR

2013-01-01

... materials as defined in this part that are located at a site where milling operations are no longer active... defined in this part that is located at a site where milling operations are no longer active, if such site... 10 Energy 1 2013-01-01 2013-01-01 false Coverage of inactive tailings sites. 40.2a Section 40.2a...

Advanced Ground Systems Maintenance Prognostics Project

NASA Technical Reports Server (NTRS)

Perotti, Jose M.

2015-01-01

The project implements prognostics capabilities to predict when a component system or subsystem will no longer meet desired functional or performance criteria, called the end of life. The capability also provides an assessment of the remaining useful life of a hardware component. The project enables the delivery of system health advisories to ground system operators. This project will use modeling techniques and algorithms to assess components' health andpredict remaining life for such components. The prognostics capability being developed will beused:during the design phase and during pre/post operations to conduct planning and analysis ofsystem design, maintenance & logistics plans, and system/mission operations plansduring real-time operations to monitor changes to components' health and assess their impacton operations.This capability will be interfaced to Ground Operations' command and control system as a part ofthe AGSM project to help assure system availability and mission success. The initial modelingeffort for this capability will be developed for Liquid Oxygen ground loading applications.

Comparison of surgical outcomes among infants in neonatal intensive care units treated by pediatric surgeons versus general surgeons: The need for pediatric surgery specialists.

PubMed

Boo, Yoon Jung; Lee, Eun Hee; Lee, Ji Sung

2017-11-01

This study compared the outcomes of infants who underwent surgery in neonatal intensive care units by pediatric surgeons and by general surgeons. This was a retrospective study of infants who underwent surgery in neonatal intensive care units between 2010 and 2014. A total of 227 patients were included. Of these patients, 116 were operated on by pediatric surgeons (PS) and 111 were operated on by general surgeons (GS). The outcome measures were the overall rate of operative complications, unplanned reoperation, mortality rate, length of stay, operative time, and number of total number of operative procedures. The overall operative complication rate was higher in the GS group compared with the PS group (18.7% vs. 7.0%, p=0.0091). The rate of unplanned reoperations was also higher in the GS group (10.8% vs. 3.5%, p=0.0331). The median operation time (90min vs. 75min, p=0.0474) and median length of stay (24days vs. 18days, p=0.0075) were significantly longer in the GS group. The adjusted odd ratios of postoperative complications for GS were 2.9 times higher than that of PS (OR 2.90, p=0.0352). The operative quality and patient outcomes of the PS group were superior to those of the GS group. III. Copyright © 2017 Elsevier Inc. All rights reserved.

Review and meta-analysis of prospective randomized controlled trials (RCTs) comparing laparo-endoscopic single site and multiport laparoscopy in gynecologic operative procedures.

PubMed

Pontis, Alessandro; Sedda, Federica; Mereu, Liliana; Podda, Mauro; Melis, Gian Benedetto; Pisanu, Adolfo; Angioni, Stefano

2016-09-01

To critically appraise published randomized controlled trials (RCTs) comparing laparo-endoscopic single site (LESS) and multi-port laparoscopic (MPL) in gynecologic operative surgery; the aim was to assess feasibility, safety, and potential benefits of LESS in comparison to MPL. A systematic review and meta-analysis of eleven RCTs. Women undergoing operative LESS and MPL gynecologic procedure (hysterectomy, cystectomy, salpingectomy, salpingo-oophorectomy, myomectomy). Outcomes evaluated were as follows: postoperative overall morbidity, postoperative pain evaluation at 6, 12, 24 and 48 h, cosmetic patient satisfaction, conversion rate, body mass index (BMI), operative time, blood loss, hemoglobin drop, postoperative hospital stay. Eleven RCTs comprising 956 women with gynecologic surgical disease randomized to either LESS (477) or MPL procedures (479) were analyzed systematically. The LESS approach is a surgical procedure with longer operative and better cosmetic results time than MPL but without statistical significance. Operative outcomes, postoperative recovery, postoperative morbidity and patient satisfaction are similar in LESS and MPL. LESS may be considered an alternative to MPL with comparable feasibility and safety in gynecologic operative procedures. However, it does not offer the expected advantages in terms of postoperative pain and cosmetic satisfaction.

The 6,000 Mile Screwdriver is Getting Longer: Washington’s Strengthening Grip

DTIC Science & Technology

2012-04-01

OMB No. 0704-0188 Public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for... information . Send comments regarding this burden estimate or any other aspect of this collection of information , including suggestions for reducing...this burden to Department of Defense, Washington Headquarters Services, Directorate for Information Operations and Reports (0704-0188), 1215 Jefferson

Software Engineering and Its Application to Avionics

DTIC Science & Technology

1988-01-01

34Automated Software Development Methodolgy (ASDM): An Architecture of a Knowledge-Based Expert System," Masters Thesis , Florida Atlantic University, Boca...operating system provides the control semnrim and aplication services within the miltiproossur system. Them processes timt aks up the application sofhwae...as a high-value target may no longer be occupied by the time the film is processed and analyzed. With the high mobility of today’s enemy forces

Transanal hemorrhoidal dearterialization with mucopexy versus open hemorrhoidectomy in the treatment of hemorrhoids: a meta-analysis of randomized control trials.

PubMed

Xu, L; Chen, H; Lin, G; Ge, Q; Qi, H; He, X

2016-12-01

The aim of this study was to analyse the outcomes of transanal hemorrhoidal dearterialization with mucopexy (THDm) versus open hemorrhoidectomy (OH) in the management of hemorrhoids. Randomized controlled trials in English were found by searching PubMed, Web of science, EMBASE, and the Cochrane Library database. Trials that compared THDm with OH were identified. Data were extracted independently for each study, and a meta-analysis was performed using fixed and random effects models. Four trials, including 316 patients, met the inclusion criteria. No statistically significant differences were noted in either total complications or postoperative bleeding, incontinence, recurrent prolapse, and urinary retention rate. Operative time was significantly longer for THDm with Doppler guidance than for THDm without Doppler guidance. Patients returned to normal activities faster after THDm than after OH. No statistically significant differences between THDm and OH were noted with regard to recurrence and reoperation rates. Our meta-analysis shows that THDm and OH are equally effective and can be attempted for the management of hemorrhoids. However, for THDm with Doppler guidance, more instruments and a longer operative time are required. Future large-scale, high-quality, multicenter trials with long-term outcomes are needed to prove these results and determine whether Doppler guidance in THD is truly necessary or not.

Comparison of clinical outcomes of open, laparoscopic and single port appendicectomies

PubMed Central

Jiang, X; Meng, HB; Zhou, DL; Ding, WX

2013-01-01

Introduction Appendicectomy is the most common surgical procedure performed in general surgery. This study aimed to compare the outcomes of open appendicectomy (OA), laparoscopic appendicectomy (LA) and single port laparoscopic appendicectomy (SPLA). Methods Fifty consecutive patients with suspected acute appendicitis were studied (OA: n=20, LA: n=20, SPLA: n=10). Clinical outcomes were compared between the three groups in terms of operative time, blood loss, postoperative complications, length of hospital stay and cost. Results Patient demographics were similar among groups (p>0.05). SPLA was characterised by longer operative time (88.1 minutes vs 35.6 minutes in OA and 33.4 minutes in LA) and higher costs (12.84 thousand Chinese yuan [RMB] vs 8.41 thousand RMB in LA and 4.99 thousand RMB in OA). OA was characterised by more blood loss (9.8ml vs 7.5ml in SPLA and 6.8ml in LA), longer hospital stay (7.5 days vs 3.5 days in LA and 3.4 days in SPLA) and lower costs. The total number of complications was higher for OA (n=2) than for LA and SPLA (n=0) although this was not statistically significant. Conclusions Where feasible, LA should be undertaken as the initial treatment of choice for most cases of suspected appendicitis. PMID:24112490

Analysis of Active Sensor Discrimination Requirements for Various Defense Missile Defense Scenarios Final Report 1999(99-ERD-080)

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

Ledebuhr, A.G.; Ng, L.C.; Gaughan, R.J.

2000-02-15

During FY99, we have explored and analyzed a combined passive/active sensor concept to support the advanced discrimination requirements for various missile defense scenario. The idea is to combine multiple IR spectral channels with an imaging LIDAR (Light Detection and Ranging) behind a common optical system. The imaging LIDAR would itself consist of at least two channels; one at the fundamental laser wavelength (e.g., the 1.064 {micro}m for Nd:YAG) and one channel at the frequency doubled (at 532 nm for Nd:YAG). two-color laser output would, for example, allow the longer wavelength for a direct detection time of flight ranger and anmore » active imaging channel at the shorter wavelength. The LIDAR can function as a high-resolution 2D spatial image either passively or actively with laser illumination. Advances in laser design also offer three color (frequency tripled) systems, high rep-rate operation, better pumping efficiencies that can provide longer distance acquisition, and ranging for enhanced discrimination phenomenology. New detector developments can enhance the performance and operation of both LIDAR channels. A real time data fusion approach that combines multi-spectral IR phenomenology with LIDAR imagery can improve both discrimination and aim-point selection capability.« less

Effects of a Longer Detection Window in VHF Time-of-Arrival Lightning Detection Systems

NASA Astrophysics Data System (ADS)

Murphy, M.; Holle, R.; Demetriades, N.

2003-12-01

Lightning detection systems that operate by measuring the times of arrival (TOA) of short bursts of radiation at VHF can produce huge volumes of data. The first automated system of this kind, the NASA Kennedy Space Center LDAR network, is capable of producing one detection every 100 usec from each of seven sensors (Lennon and Maier, 1991), where each detection consists of the time and amplitude of the highest-amplitude peak observed within the 100 usec window. More modern systems have been shown to produce very detailed information with one detection every 10 usec (Rison et al., 2001). Operating such systems in real time, however, can become expensive because of the large data communications rates required. One solution to this problem is to use a longer detection window, say 500 usec. In principle, this has little or no effect on the flash detection efficiency because each flash typically produces a very large number of these VHF bursts (known as sources). By simply taking the largest-amplitude peak from every 500-usec interval instead of every 100-usec interval, we should detect the largest 20{%} of the sources that would have been detected using the 100-usec window. However, questions remain about the exact effect of a longer detection window on the source detection efficiency with distance from the network, its effects on how well flashes are represented in space, and how well the reduced information represents the parent thunderstorm. The latter issue is relevant for automated location and tracking of thunderstorm cells using data from VHF TOA lightning detection networks, as well as for understanding relationships between lightning and severe weather. References Lennon, C.L. and L.M. Maier, Lightning mapping system. Proceedings, Intl. Aerospace and Ground Conf. on Lightning and Static Elec., Cocoa Beach, Fla., NASA Conf. Pub. 3106, vol. II, pp. 89-1 - 89-10, 1991. Rison, W., P. Krehbiel, R. Thomas, T. Hamlin, J. Harlin, High time resolution lightning mapping observations of a small thunderstorm during STEPS. Eos Trans. AGU, 82 (47), Fall Meet. Suppl., Abstract AE12A-83, 2001.

Case-Mix Variables and Predictors for Outcomes of Laparoscopic Hysterectomy: A Systematic Review.

PubMed

Driessen, Sara R C; Sandberg, Evelien M; la Chapelle, Claire F; Twijnstra, Andries R H; Rhemrev, Johann P T; Jansen, Frank Willem

2016-01-01

The assessment of surgical quality is complex, and an adequate case-mix correction is missing in currently applied quality indicators. The purpose of this study is to give an overview of all studies mentioning statistically significant associations between patient characteristics and surgical outcomes for laparoscopic hysterectomy (LH). Additionally, we identified a set of potential case-mix characteristics for LH. This systematic review was conducted according to the Meta-Analysis of Observational Studies in Epidemiology guidelines. We searched PubMed and EMBASE from January 1, 2000 to August 1, 2015. All articles describing statistically significant associations between patient characteristics and adverse outcomes of LH for benign indications were included. Primary outcomes were blood loss, operative time, conversion, and complications. The methodologic quality of the included studies was assessed using the Newcastle-Ottawa Quality Assessment Scale. The included articles were summed per predictor and surgical outcome. Three sets of case-mix characteristics were determined, stratified by different levels of evidence. Eighty-five of 1549 identified studies were considered eligible. Uterine weight and body mass index (BMI) were the most mentioned predictors (described, respectively, 83 and 45 times) in high quality studies. For longer operative time and higher blood loss, uterine weight ≥ 250 to 300 g and ≥500 g and BMI ≥ 30 kg/m(2) dominated as predictors. Previous operations, adhesions, and higher age were also considered as predictors for longer operative time. For complications and conversions, the patient characteristics varied widely, and uterine weight, BMI, previous operations, adhesions, and age predominated. Studies of high methodologic quality indicated uterine weight and BMI as relevant case-mix characteristics for all surgical outcomes. For future development of quality indicators of LH and to compare surgical outcomes adequately, a case-mix correction is suggested for at least uterine weight and BMI. A potential case-mix correction for adhesions and previous operations can be considered. For both surgeons and patients it is valuable to be aware of potential factors predicting adverse outcomes and to anticipate this. Finally, to benchmark clinical outcomes at an international level, it is of the utmost importance to introduce uniform outcome definitions. Copyright © 2016 AAGL. Published by Elsevier Inc. All rights reserved.

Laparoscopic versus open incisional hernia repair: a retrospective cohort study with costs analysis on 269 patients.

PubMed

Soliani, G; De Troia, A; Portinari, M; Targa, S; Carcoforo, P; Vasquez, G; Fisichella, P M; Feo, C V

2017-08-01

To compare clinical outcomes and institutional costs of elective laparoscopic and open incisional hernia mesh repairs and to identify independent predictors of prolonged operative time and hospital length of stay (LOS). Retrospective observational cohort study on 269 consecutive patients who underwent elective incisional hernia mesh repair, laparoscopic group (N = 94) and open group (N = 175), between May 2004 and July 2014. Operative time was shorter in the laparoscopic versus open group (p < 0.0001). Perioperative morbidity and mortality were similar in the two groups. Patients in the laparoscopic group were discharged a median of 2 days earlier (p < 0.0001). At a median follow-up over 50 months, no difference in hernia recurrence was detected between the groups. In laparoscopic group total institutional costs were lower (p = 0.02). At Cox regression analysis adjusted for potential confounders, large wall defect (W3) and higher operative risk (ASA score 3-4) were associated with prolonged operative time, while midline hernia site was associated with increased hospital LOS. Open surgical approach was associated with prolongation of both operative time and LOS. Laparoscopic approach may be considered safely to all patients for incisional hernia repair, regardless of patients' characteristics (age, gender, BMI, ASA score, comorbidities) and size of the wall defect (W2-3), with the advantage of shorter operating time and hospital LOS that yields reduced total institutional costs. Patients with higher ASA score and large hernia defects are at risk of prolonged operative time, while an open approach is associated with longer duration of surgical operation and hospital LOS.

National trends of perioperative outcomes and costs for open, laparoscopic and robotic pediatric pyeloplasty.

PubMed

Varda, Briony K; Johnson, Emilie K; Clark, Curtis; Chung, Benjamin I; Nelson, Caleb P; Chang, Steven L

2014-04-01

We performed a population based study comparing trends in perioperative outcomes and costs for open, laparoscopic and robotic pediatric pyeloplasty. Specific billing items contributing to cost were also investigated. Using the Perspective database (Premier, Inc., Charlotte, North Carolina), we identified 12,662 pediatric patients who underwent open, laparoscopic and robotic pyeloplasty (ICD-9 55.87) in the United States from 2003 to 2010. Univariate and multivariate statistics were used to evaluate perioperative outcomes, complications and costs for the competing surgical approaches. Propensity weighting was used to minimize selection bias. Sampling weights were used to yield a nationally representative sample. A decrease in open pyeloplasty and an increase in minimally invasive pyeloplasty were observed. All procedures had low complication rates. Compared to open pyeloplasty, laparoscopic and robotic pyeloplasty had longer median operative times (240 minutes, p <0.0001 and 270 minutes, p <0.0001, respectively). There was no difference in median length of stay. Median total cost was lower among patients undergoing open vs robotic pyeloplasty ($7,221 vs $10,780, p <0.001). This cost difference was largely attributable to robotic supply costs. During the study period open pyeloplasty made up a declining majority of cases. Use of laparoscopic pyeloplasty plateaued, while robotic pyeloplasty increased. Operative time was longer for minimally invasive pyeloplasty, while length of stay was equivalent across all procedures. A higher cost associated with robotic pyeloplasty was driven by operating room use and robotic equipment costs, which nullified low room and board cost. This study reflects an adoption period for robotic pyeloplasty. With time, perioperative outcomes and cost may improve. Copyright © 2014 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Feasibility of four-arm robotic lobectomy as solo surgery in patients with clinical stage I lung cancer.

PubMed

Park, Seong Yong; Suh, Jee Won; Narm, Kyoung Sik; Lee, Chang Young; Lee, Jin Gu; Paik, Hyo Chae; Chung, Kyoung Young; Kim, Dae Joon

2017-06-01

This study was performed to investigate the feasibility of four-arm robotic lobectomy (FARL) as a solo surgical technique in patients with non-small cell lung cancer (NSCLC). Early outcome and long-term survival of FARL were compared with those of video-assisted thoracoscopic lobectomy (VATL). Prospective enrollment of patients with clinical stage I NSCLC undergoing FARL or VATL (20 patients in each group) was planned. Interim analysis for early postoperative outcome was performed after the initial 10 cases in each group. The study was terminated early because of safety issues in the FARL group after enrollment of 12 FARL and 17 VATL patients from 2011 to 2012. There were no differences in clinical characteristics between groups. Lobectomy time and total operation time were significantly longer in the FARL group (P=0.003). There were three life-threatening events in the FARL group (2 bleedings, 1 bronchus tear) that necessitated thoracotomy conversion in 1 patient. There were no differences in other operative outcomes including pain score, complications, or length of hospital stay. Pathologic stage and number of dissected lymph nodes (LNs) were also comparable. During a follow-up of 48.9±9.5 months, recurrence was identified in 2 (16.7%) patients in FARL group and 3 (23.5%) in VATL group. Five-year overall survival (100% vs . 87.5%, P=0.386) and disease-free survival (82.5% vs . 75.6%, P=0.589) were comparable. FARL as solo surgery could not be recommended because of safety issues. It required a longer operation time and had no benefits over VATL in terms of early postoperative outcome or long-term survival.

Longer aftershocks duration in extensional tectonic settings.

PubMed

Valerio, E; Tizzani, P; Carminati, E; Doglioni, C

2017-11-27

Aftershocks number decay through time, depending on several parameters peculiar to each seismogenic regions, including mainshock magnitude, crustal rheology, and stress changes along the fault. However, the exact role of these parameters in controlling the duration of the aftershock sequence is still unknown. Here, using two methodologies, we show that the tectonic setting primarily controls the duration of aftershocks. On average and for a given mainshock magnitude (1) aftershock sequences are longer and (2) the number of earthquakes is greater in extensional tectonic settings than in contractional ones. We interpret this difference as related to the different type of energy dissipated during earthquakes. In detail, (1) a joint effect of gravitational forces and pure elastic stress release governs extensional earthquakes, whereas (2) pure elastic stress release controls contractional earthquakes. Accordingly, normal faults operate in favour of gravity, preserving inertia for a longer period and seismicity lasts until gravitational equilibrium is reached. Vice versa, thrusts act against gravity, exhaust their inertia faster and the elastic energy dissipation is buffered by the gravitational force. Hence, for seismic sequences of comparable magnitude and rheological parameters, aftershocks last longer in extensional settings because gravity favours the collapse of the hangingwall volumes.

Comparison of VATS and Robotic Approaches For Clinical Stage I and II NSCLC Using the STS Database

PubMed Central

Louie, Brian E.; Wilson, Jennifer L.; Kim, Sunghee; Cerfolio, Robert J.; Park, Bernard J.; Farivar, Alexander S.; Vallières, Eric; Aye, Ralph W.; Burfeind, William R.; Block, Mark I.

2016-01-01

Background Data from selected centers show that robotic lobectomy (RL) is safe, effective and has comparable 30-day mortality to video assisted lobectomy (VATS). However, widespread adoption of RL is controversial. We used the STS-GTS-Database to evaluate quality metrics for these two minimally invasive lobectomy techniques. Methods A database query for primary clinical stage I or II NSCLC at high volume centers from 2009 to 2013 identified 1,220 RLs and 12,378 VATS. Quality metrics evaluated included operative morbidity, 30-day mortality and nodal upstaging (NU), defined as cN0 to pN1. Multivariable logistic regression was used to evaluate NU. Results RL patients were older, less active, less likely to be an ever smoker, and had higher BMI (all p<0.05). They were also more likely to have coronary heart disease or hypertension (all p<0.001) and to have had preoperative mediastinal staging (p<0.0001). RL operative times were longer (median 186 vs 173 min, p<0.001); all other operative parameters were similar. All postoperative outcomes were similar including complications and 30-day mortality (RL 0.6% vs VATS 0.8%, p=0.4). Median length of stay was 4 days for both, but a higher proportion of RLs stayed < 4 days: 48% vs 39%, p<0.001. NU overall was similar (p=0.6), but with trends favoring VATS in the cT1b group, and RL in the cT2a group. Conclusions RL patients had more co-morbidities and RL operative times were longer, but quality outcome measures including complications, hospital stay, 30-day mortality, and NU suggest RL and VATS are equivalent. PMID:27209613

Exploring the Role of Polycythemia in Patients With Cyanosis After Palliative Congenital Heart Surgery.

PubMed

Siehr, Stephanie L; Shi, Shenghui; Hao, Shiying; Hu, Zhongkai; Jin, Bo; Hanley, Frank; Reddy, Vadiyala Mohan; McElhinney, Doff B; Ling, Xuefeng Bruce; Shin, Andrew Y

2016-03-01

To understand the relationship between polycythemia and clinical outcome in patients with hypoplastic left heart syndrome following the Norwood operation. A retrospective, single-center cohort study. Pediatric cardiovascular ICU, university-affiliated children's hospital. Infants with hypoplastic left heart syndrome admitted to our medical center from September 2009 to December 2012 undergoing stage 1/Norwood operation. None. Baseline demographic and clinical information including first recorded postoperative hematocrit and subsequent mean, median, and nadir hematocrits during the first 72 hours postoperatively were recorded. The primary outcomes were in-hospital mortality and length of hospitalization. Thirty-two patients were included in the analysis. Patients did not differ by operative factors (cardiopulmonary bypass time and cross-clamp time) or traditional markers of severity of illness (vasoactive inotrope score, lactate, saturation, and PaO2/FIO2 ratio). Early polycythemia (hematocrit value > 49%) was associated with longer cardiovascular ICU stay (51.0 [± 38.6] vs 21.4 [± 16.2] d; p < 0.01) and total hospital length of stay (65.0 [± 46.5] vs 36.1 [± 20.0] d; p = 0.03). In a multivariable analysis, polycythemia remained independently associated with the length of hospitalization after controlling for the amount of RBC transfusion (weight, 4.36 [95% CI, 1.35-7.37]; p < 0.01). No difference in in-hospital mortality rates was detected between the two groups (17.6% vs 20%). Early polycythemia following the Norwood operation is associated with longer length of hospitalization even after controlling for blood cell transfusion practices. We hypothesize that polycythemia may be caused by hemoconcentration and used as an early marker of capillary leak syndrome.

Comparison of 3 Minimally Invasive Methods for Distal Tibia Fractures.

PubMed

Fang, Jun-Hao; Wu, Yao-Sen; Guo, Xiao-Shan; Sun, Liao-Jun

2016-07-01

This study compared the results of external fixation combined with limited open reduction and internal fixation (EF + LORIF), minimally invasive percutaneous plate osteosynthesis (MIPPO), and intramedullary nailing (IMN) for distal tibia fractures. A total of 84 patients with distal tibia shaft fractures were randomized to operative stabilization using EF + LORIF (28 cases), MIPPO (28 cases), or IMN (28 cases). The 3 groups were comparable with respect to patient demographics. Data were collected on operative time and radiation time, union time, complications, time of recovery to work, secondary operations, and measured joint function using the American Orthopaedic Foot and Ankle Society (AOFAS) score. There was no significant difference in time to union, incidence of union status, time of recovery to work, and AOFAS scores among the 3 groups (P>.05). Mean operative time and radiation time in the MIPPO group were longer than those in the IMN or EF + LORIF groups (P<.05). Wound complications after MIPPO were more common compared with IMN or EF + LORIF (P<.05). Anterior knee pain occurred frequently after IMN (32.1%), and irritation symptoms were encountered more frequently after MIPPO (46.4%). Although EF + LORIF was associated with fewer secondary procedures vs MIPPO or IMN, it was related with more pin-tract infections (14.3%). Findings indicated that EF + LORIF, MIPPO, and IMN all achieved similar good functional results. However, EF + LORIF had some advantages over MIPPO and IMN in reducing operative and radiation times, postoperative complications, and reoperation rate. [Orthopedics. 2016; 39(4):e627-e633.]. Copyright 2016, SLACK Incorporated.

Efficacy of tension-free vaginal tape compared with transobturator tape in the treatment of stress urinary incontinence in women: analysis of learning curve, perioperative changes of voiding function

PubMed Central

2011-01-01

Background In this study, by comparing TVT surgery and TOT surgery for stress urinary incontinence in women, the characteristics and learning curves of both operative methods were studied. Methods A total of 83 women with stress urinary incontinence treated with tension-free vaginal tape (TVT) (n = 38) or transobturator tape (TOT) (n = 45) at Saiseikai Central Hospital between April 2004 and September 2009 were included. We compare the outcomes and learning curves between TVT surgery and TOT surgery. In statistical analysis, Student's t test, Fisher's exact test, and Mann-Whitney's U test were used. Results The surgical durations were 37.4 ± 15.7 minutes with TVT surgery and 31.0 ± 8.3 minutes with TOT surgery. A longer period of time was required for TVT surgery (p = 0.025). The residual urine at post-operative day 1 was higher in TVT surgery (25.9 ± 44.2 ml) than in TOT surgery (10.6 ± 19.2 ml) (p = 0.0452). The surgical duration of TVT surgery was shortened after the operator had performed 15 operations (p = 0.019). Conclusions In comparison of TVT surgery and TOT surgery, the surgical duration of TVT surgery was longer and the residual urine of TVT surgery was higher at post-operative day 1. Surgical experience could shorten the duration of TVT surgery. PMID:21726448

Anterolateral minithoracotomy versus median sternotomy for the treatment of congenital heart defects: a meta-analysis and systematic review

PubMed Central

2012-01-01

Background Anterolateral Minithoracotomy (ALMT) for the radical correction of Congenital Heart Defects is an alternative to Median Sternotomy (MS) due to reduce operative trauma accelerating recovery and yield a better cosmetic outcome after surgery. Our purpose is to conduct whether ALMT would bring more short-term benefits to patients than conventional Median Sternotomy by using a meta-analysis of case–control study in the published English Journal. Methods 6 case control studies published in English from 1997 to 2011 were identified and synthesized to compare the short-term postoperative outcomes between ALMT and MS. These outcomes were cardiopulmonary bypass time, aortic cross-clamp time, intubation time, intensive care unit stay time, and postoperative hospital stay time. Results ALMT had significantly longer cardiopulmonary bypass times (8.00 min more, 95% CI 0.36 to 15.64 min, p = 0.04). Some evidence proved that aortic cross-clamp time of ALMT was longer, yet not significantly (2.38 min more, 95% CI −0.15 to 4.91 min, p = 0.06). In addition, ALMT had significantly shorter intubation time (1.66 hrs less, 95% CI −3.05 to −0.27 hrs, p = 0.02). Postoperative hospital stay time was significantly shorter with ALMT (1.52 days less, 95% CI −2.71 to −0.33 days, p = 0.01). Some evidence suggested a reduction in ICU stay time in the ALMT group. However, this did not prove to be statistically significant (0.88 days less, 95% CI −0.81 to 0.04 days, p = 0.08). Conclusion ALMT can bring more benefits to patients with Congenital Heart Defects by reducing intubation time and postoperative hospital stay time, though ALMT has longer CPB time and aortic cross-clamp time. PMID:22559820

An operations concept methodology to achieve low-cost mission operations

NASA Technical Reports Server (NTRS)

Ledbetter, Kenneth W.; Wall, Stephen D.

1993-01-01

Historically, the Mission Operations System (MOS) for a space mission has been designed last because it is needed last. This has usually meant that the ground system must adjust to the flight vehicle design, sometimes at a significant cost. As newer missions have increasingly longer flight operations lifetimes, the MOS becomes proportionally more difficult and more resource-consuming. We can no longer afford to design the MOS last. The MOS concept may well drive the spacecraft, instrument, and mission designs, as well as the ground system. A method to help avoid these difficulties, responding to the changing nature of mission operations is presented. Proper development and use of an Operations Concept document results in a combined flight and ground system design yielding enhanced operability and producing increased flexibility for less cost.

Modeling the transport of nitrogen in an NPP-2006 reactor circuit

NASA Astrophysics Data System (ADS)

Stepanov, O. E.; Galkin, I. Yu.; Sledkov, R. M.; Melekh, S. S.; Strebnev, N. A.

2016-07-01

Efficient radiation protection of the public and personnel requires detecting an accident-initiating event quickly. Specifically, if a heat-exchange tube in a steam generator is ruptured, the 16N radioactive nitrogen isotope, which contributes to a sharp increase in the steam activity before the turbine, may serve as the signaling component. This isotope is produced in the core coolant and is transported along the circulation circuit. The aim of the present study was to model the transport of 16N in the primary and the secondary circuits of a VVER-1000 reactor facility (RF) under nominal operation conditions. KORSAR/GP and RELAP5/Mod.3.2 codes were used to perform the calculations. Computational models incorporating the major components of the primary and the secondary circuits of an NPP-2006 RF were constructed. These computational models were subjected to cross-verification, and the calculation results were compared to the experimental data on the distribution of the void fraction over the steam generator height. The models were proven to be valid. It was found that the time of nitrogen transport from the core to the heat-exchange tube leak was no longer than 1 s under RF operation at a power level of 100% N nom with all primary circuit pumps activated. The time of nitrogen transport from the leak to the γ-radiation detection unit under the same operating conditions was no longer than 9 s, and the nitrogen concentration in steam was no less than 1.4% (by mass) of its concentration at the reactor outlet. These values were obtained using conservative approaches to estimating the leak flow and the transport time, but the radioactive decay of nitrogen was not taken into account. Further research concerned with the calculation of thermohydraulic processes should be focused on modeling the transport of nitrogen under RF operation with some primary circuit pumps deactivated.

Employing ISRU Models to Improve Hardware Design

NASA Technical Reports Server (NTRS)

Linne, Diane L.

2010-01-01

An analytical model for hydrogen reduction of regolith was used to investigate the effects of several key variables on the energy and mass performance of reactors for a lunar in-situ resource utilization oxygen production plant. Reactor geometry, reaction time, number of reactors, heat recuperation, heat loss, and operating pressure were all studied to guide hardware designers who are developing future prototype reactors. The effects of heat recuperation where the incoming regolith is pre-heated by the hot spent regolith before transfer was also investigated for the first time. In general, longer reaction times per batch provide a lower overall energy, but also result in larger and heavier reactors. Three reactors with long heat-up times results in similar energy requirements as a two-reactor system with all other parameters the same. Three reactors with heat recuperation results in energy reductions of 20 to 40 percent compared to a three-reactor system with no heat recuperation. Increasing operating pressure can provide similar energy reductions as heat recuperation for the same reaction times.

Gain stabilization control system of the upgraded magnetic proton recoil neutron spectrometer at JET.

PubMed

Sjöstrand, Henrik; Andersson Sundén, E; Conroy, S; Ericsson, G; Gatu Johnson, M; Giacomelli, L; Gorini, G; Hellesen, C; Hjalmarsson, A; Popovichev, S; Ronchi, E; Tardocchi, M; Weiszflog, M

2009-06-01

Burning plasma experiments such as ITER and DEMO require diagnostics capable of withstanding the harsh environment generated by the intense neutron flux and to maintain stable operating conditions for times longer than present day systems. For these reasons, advanced control and monitoring (CM) systems will be necessary for the reliable operation of diagnostics. This paper describes the CM system of the upgraded magnetic proton recoil neutron spectrometer installed at the Joint European Torus focusing in particular on a technique for the stabilization of the gain of the photomultipliers coupled to the neutron detectors. The results presented here show that this technique provides good results over long time scales. The technique is of general interest for all diagnostics that employ scintillators coupled to photomultiplier tubes.

Prospects for Ultra-Stable Timekeeping with Sealed Vacuum Operation in Multi-Pole Linear Ion Trap Standards

NASA Technical Reports Server (NTRS)

Burt, Eric A.; Tjoelker, R. L.

2007-01-01

A recent long-term comparison between the compensated multi-pole Linear Ion Trap Standard (LITS) and the laser-cooled primary standards via GPS carrier phase time transfer showed a deviation of less than 2.7x10(exp -17)/day. A subsequent evaluation of potential drift contributors in the LITS showed that the leading candidates are fluctuations in background gases and the neon buffer gas. The current vacuum system employs a "flow-through" turbomolecular pump and a diaphragm fore pump. Here we consider the viability of a "sealed" vacuum system pumped by a non-evaporable getter for long-term ultra-stable clock operation. Initial tests suggests that both further stability improvement and longer mean-time-between-maintenance can be achieved using this approach

Preliminary assessment of accident-tolerant fuels on LWR performance during normal operation and under DB and BDB accident conditions

NASA Astrophysics Data System (ADS)

Ott, L. J.; Robb, K. R.; Wang, D.

2014-05-01

Following the severe accidents at the Japanese Fukushima Daiichi Nuclear Power Station in 2011, the US Department of Energy initiated research and development on the enhancement of the accident tolerance of light water reactors by the development of fuels/cladding that, in comparison with the standard UO2/Zircaloy (Zr) system, can tolerate loss of active cooling in the core for a considerably longer time period while maintaining or improving the fuel performance during normal operations. Analyses are presented that illustrate the impact of these new candidate fuel/cladding materials on the fuel performance at normal operating conditions and on the reactor system under DB and BDB accident conditions.

Surgery in adrenocortical carcinoma: Importance of national cooperation and centralized surgery.

PubMed

Hermsen, Ilse G C; Kerkhofs, Thomas M A; den Butter, Gijsbert; Kievit, Job; van Eijck, Casper H J; Nieveen van Dijkum, Els J M; Haak, Harm R

2012-07-01

The low incidence rate of adrenocortical carcinoma (ACC) requires a multidisciplinary approach in which surgery plays an essential role because complete resection of the primary tumor is the only chance of cure. To improve patient care, insight into operative results within the ACC population is essential. In 2007, a Dutch Adrenal Network Registry was created covering care and outcome of patients treated for ACC in the Netherlands since 1965. Using this database, we performed a study (1) to gain insight into surgical performance in the Netherlands and (2) to compare operative data with international literature. Data on patients treated from 1965 until January 2008 were studied. The following data were collected: age, gender, functionality of the tumor, stage at diagnosis, operative procedure, completeness of surgery, disease recurrence, adjuvant mitotane therapy, and recurrence-free and overall survival (OS). A total of 175 patients were studied, of whom 149 underwent surgery. Patients with complete resection had significantly longer OS times than patients with incomplete resection (P = .010). Patients operated on in a Dutch Adrenal Network center had significantly longer duration of OS in both univariate (P = .011) and multivariate analysis (P = .014). A significantly greater OS was observed for operated stage IV patients compared with nonoperated patients (P = .002). Our data suggest the relevance of national cooperation and centralized surgery in ACC. For selected patients with stage IV disease, surgery can be beneficial in extending survival. On the basis of the retrospective analysis, operative ACC in the Netherlands can and will be improved. Copyright © 2012. Published by Mosby, Inc.

The winter gap effect in methane leak detection and repair with optical gas imaging cameras

NASA Astrophysics Data System (ADS)

Fox, T. A.; Barchyn, T.; Hugenholtz, C.

2017-12-01

Implementing effective leak detection and repair (LDAR) programs is essential for mitigating fugitive methane emissions from oil and gas operations. In Canada, newly proposed regulations will require that high-risk facilities be surveyed 3 times/yr for fugitive leaks. Like the United States, Canada promotes the use of Optical Gas Imaging cameras (OGIs) for detecting natural gas leaks during LDAR surveys. However, recent research suggests OGIs may perform poorly under adverse environmental conditions, especially in low temperatures. For regions like Canada that experience cold winters, OGIs may not be reliably used for months at a time, meaning that leaks may accumulate and emit for longer periods before being repaired. While considerable oil and gas activity occurs in high-latitude regions with cold winters, no research has explored how extended cold periods impact OGI-focused LDAR programs. To improve this understanding, we present a simple model exploring relationships among winter gap length, fugitive methane emissions, and investment input for LDAR programs employing OGI instruments in gas producing regions of different latitudes. Preliminary results suggest that longer gaps between LDAR surveys caused by cold temperatures result in either 1) higher total emissions for the year, or 2) greater time and equipment investment in LDAR programs to achieve emissions mitigation equivalent to LDAR programs operating under ideal conditions. When weather constraints are removed and LDAR surveys are evenly spaced throughout the year, emissions mitigation is optimized. However, as the winter gap duration and the size of the implicated area increases, fugitive leaks last longer. Furthermore, a spillover effect is observed as LDAR crews become overwhelmed with the high volume of work required as temperatures increase in the spring. Our model adds weight to the argument that LDAR programs should be tailored to regional needs, and that regulators should be more cognisant of sensor-specific limitations as they develop LDAR protocols.

Out-of-office hours' elective surgical intensive care admissions and their associated complications.

PubMed

Morgan, David J R; Ho, Kwok Ming; Ong, Yang Jian; Kolybaba, Marlene L

2017-11-01

The 'weekend' effect is a controversial theory that links reduced staffing levels, staffing seniority and supportive services at hospitals during 'out-of-office hours' time periods with worsening patient outcomes. It is uncertain whether admitting elective surgery patients to intensive care units (ICU) during 'out-of-office hours' time periods mitigates this affect through higher staffing ratios and seniority. Over a 3-year period in Western Australia's largest private hospital, this retrospective nested-cohort study compared all elective surgical patients admitted to the ICU based on whether their admission occurred 'in-office hours' (Monday-Friday 08.00-18.00 hours) or 'out-of-office hours' (all other times). The main outcomes were surgical complications using the Dindo-Clavien classification and length-of-stay data. Of the total 4363 ICU admissions, 3584 ICU admissions were planned following elective surgery resulting in 2515 (70.2%) in-office hours and 1069 (29.8%) out-of-office hours elective ICU surgical admissions. Out-of-office hours ICU admissions following elective surgery were associated with an increased risk of infection (P = 0.029), blood transfusion (P = 0.020), total parental nutrition (P < 0.001) and unplanned re-operations (P = 0.027). Out-of-office hours ICU admissions were also associated with an increased hospital length-of-stay, with (1.74 days longer, P < 0.0001) and without (2.8 days longer, P < 0.001) adjusting for severity of acute and chronic illnesses and inter-hospital transfers (12.3 versus 9.8%, P = 0.024). Hospital mortality (1.2 versus 0.7%, P = 0.111) was low and similar between both groups. Out-of-office hours ICU admissions following elective surgery is common and associated with serious post-operative complications culminating in significantly longer hospital length-of-stays and greater transfers with important patient and health economic implications. © 2017 Royal Australasian College of Surgeons.

[Comparison of the results of laparotomy and laparoscopic surgery in patients with Crohn's disease].

PubMed

Horváth, Gyula; Simonka, Zsolt; Lázár, György

2014-01-05

Crohn's disease is an inflammatory bowel disease which may affect different parts of the gastrointestinal tract. To compare retrospectively the results of laparotomy and laparoscopic surgery performed in patients with Crohn's disease between January 1, 2005 and October 31, 2012 in the Department of Surgery, University of Szeged, Hungary. Patients were divided into two groups based on the types of surgery; 103 patients underwent laparotomy and 30 patients had laparoscopic surgery programmed. 22 patients had 24 primary acute interventions. The mean age was significantly lower in the laparoscopic surgery group (p = 0.042). The laparoscopic ileocecal resections have been found significantly shorter than laparotomies (p = 0.033). When ileocecal resection was performed the operation time was significantly longer (p = 0.033) while hospitalization time (p = 0.025) and intensive care unit treatment time (p<0.001) were shorter and the bowel passage also started earlier in the laparoscopic group as compared to the laparotomy group. Laparoscopic surgery results in smaller surgical trauma, better cosmetic outcome, shorter hospitalization time and not higher complication- and morbidity-rate as well as shorter operation time in certain cases. However, it requires more qualified surgical team and the operation expenses are higher.

Real-time monitoring of CO2 storage sites: Application to Illinois Basin-Decatur Project

USGS Publications Warehouse

Picard, G.; Berard, T.; Chabora, E.; Marsteller, S.; Greenberg, S.; Finley, R.J.; Rinck, U.; Greenaway, R.; Champagnon, C.; Davard, J.

2011-01-01

Optimization of carbon dioxide (CO2) storage operations for efficiency and safety requires use of monitoring techniques and implementation of control protocols. The monitoring techniques consist of permanent sensors and tools deployed for measurement campaigns. Large amounts of data are thus generated. These data must be managed and integrated for interpretation at different time scales. A fast interpretation loop involves combining continuous measurements from permanent sensors as they are collected to enable a rapid response to detected events; a slower loop requires combining large datasets gathered over longer operational periods from all techniques. The purpose of this paper is twofold. First, it presents an analysis of the monitoring objectives to be performed in the slow and fast interpretation loops. Second, it describes the implementation of the fast interpretation loop with a real-time monitoring system at the Illinois Basin-Decatur Project (IBDP) in Illinois, USA. ?? 2011 Published by Elsevier Ltd.

Mini-MegaTORTORA wide-field monitoring system with sub-second temporal resolution: observation of transient events

NASA Astrophysics Data System (ADS)

Karpov, S.; Beskin, G.; Biryukov, A.; Bondar, S.; Ivanov, E.; Katkova, E.; Perkov, A.; Sasyuk, V.

2016-06-01

Here we present a summary of first years of operation and first results of a novel 9-channel wide-field optical monitoring system with sub-second temporal resolution, Mini-MegaTORTORA (MMT-9), which is in operation now at Special Astrophysical Observatory on Russian Caucasus. The system is able to observe the sky simultaneously in either wide (~900 square degrees) or narrow (~100 square degrees) fields of view, either in clear light or with any combination of color (Johnson-Cousins B, V or R) and polarimetric filters installed, with exposure times ranging from 0.1 s to hundreds of seconds. The real-time system data analysis pipeline performs automatic detection of rapid transient events, both near-Earth and extragalactic. The objects routinely detected by MMT include faint meteors and artificial satellites. The pipeline for a longer time scales variability analysis is still in development.

Apollo 15 Mission Report

NASA Technical Reports Server (NTRS)

1971-01-01

A detailed discussion is presented of the Apollo 15 mission, which conducted exploration of the moon over longer periods, greater ranges, and with more instruments of scientific data acquisition than previous missions. The topics include trajectory, lunar surface science, inflight science and photography, command and service module performance, lunar module performance, lunar surface operational equipment, pilot's report, biomedical evaluation, mission support performance, assessment of mission objectives, launch phase summary, anomaly summary, and vehicle and equipment descriptions. The capability of transporting larger payloads and extending time on the moon were demonstrated. The ground-controlled TV camera allowed greater real-time participation by earth-bound personnel. The crew operated more as scientists and relied more on ground support team for systems monitoring. The modified pressure garment and portable life support system provided better mobility and extended EVA time. The lunar roving vehicle and the lunar communications relay unit were also demonstrated.

Climate effects of non-compliant Volkswagen diesel cars

NASA Astrophysics Data System (ADS)

Tanaka, Katsumasa; Lund, Marianne T.; Aamaas, Borgar; Berntsen, Terje

2018-04-01

On-road operations of Volkswagen light-duty diesel vehicles equipped with defeat devices cause emissions of NOx up to 40 times above emission standards. Higher on-road NOx emissions are a widespread problem not limited to Volkswagen vehicles, but the Volkswagen violations brought this issue under the spotlight. While several studies investigated the health impacts of high NOx emissions, the climatic impacts have not been quantified. Here we show that such diesel cars generate a larger warming on the time scale of several years but a smaller warming on the decadal time scale during actual on-road operations than in vehicle certification tests. The difference in longer-term warming levels, however, depends on underlying driving conditions. Furthermore, in the presence of defeat devices, the climatic advantage of ‘clean diesel’ cars over gasoline cars, in terms of global-mean temperature change, is in our view not necessarily the case.

Displays mounted on cutting blocks reduce the learning curve in navigated total knee arthroplasty.

PubMed

Schnurr, Christoph; Eysel, Peer; König, Dietmar Pierre

2011-01-01

The use of computer navigation in total knee arthroplasty (TKA) improves the implant alignment but increases the operation time. Studies have shown that the operation time is further prolonged due to the surgeon's learning curve, and longer operation times have been associated with higher morbidity risks. It has been our hypothesis that an improvement in the human-machine interface might reduce the time required during the learning curve. Accordingly, we asked whether the use of navigation devices with a display fixed on the surgical instruments would reduce the operation time in navigated TKAs performed by navigation beginners. Thirty medical students were randomized and used two navigation devices in rotation: these were the Kolibri® device with an external display and the Dash® device with a display that was fixed on the cutting blocks. The time for adjustment of the tibial and femoral cutting blocks on knee models while using these devices was measured. A significant time reduction was demonstration when the Dash® device was used: The time reduction was 21% for the tibial block (p = 0.007), 40% for the femoral block (p < 0.001), and 32% for the whole procedure (p < 0.001). The integrated display, fixed on surgical instruments in a manner similar to a spirit level, seems to be more user-friendly for navigation beginners. Hence, unproductive time losses during the learning curve may be diminished.

Minimization of lumen depreciation in LED lamps using thermal transient behavior analysis and design optimizations.

PubMed

Khan, M Nisa

2016-02-10

We expansively investigate thermal behaviors of various general-purpose light-emitting diode (LED) lamps and apply our measured results, validated by simulation, to establish lamp design rules for optimizing their optical and thermal properties. These design rules provide the means to minimize lumen depreciation over time by minimizing the periods for lamps to reach thermal steady-state while maintaining their high luminous efficacy and omnidirectional light distribution capability. While it is well known that minimizing the junction temperature of an LED leads to a longer lifetime and an increased lumen output, our study demonstrates, for the first time, to the best of our knowledge, that it is also important to minimize the time it takes to reach thermal equilibrium because doing so minimizes lumen depreciation and enhances light output and color stability during operation. Specifically, we have found that, in addition to inadequate heat-sink fin areas for a lamp configuration, LEDs mounted on multiple boards, as opposed to a single board, lead to longer periods for reaching thermal equilibrium contributing to larger lumen depreciation.

Postoperative paralytic ileus remains a problem following surgery for advanced pelvic cancers.

PubMed

Funder, Jonas Amstrup; Tolstrup, Rikke; Jepsen, Betina Norman; Iversen, Lene Hjerrild

2017-10-01

Paralytic postoperative ileus (POI) is associated with increased morbidity and mortality after abdominal surgery. Despite increased awareness and implementation of various measures, POI remains a problem, perhaps moreso for those patients undergoing extensive oncological surgical treatment. The aim of this study was to describe the extent of POI after advanced cancer surgery in the era of contemporary treatment modalities of POI. A retrospective analysis of all patients who underwent either abdominoperineal excision with transpelvic vertical rectus abdominal musculocutaneous (VRAM)-flap after anal cancer or pelvic exenteration at single institution from January 2012 to November 2013 was carried out. Patients were identified from operative codes, and data were retrieved from patient records. Eighty-nine patients were included in the study, 21 abdominoperineal excision and 68 pelvic exenteration procedures. Median nasogastric tube duration was 4 days (range: 0-44). Median time to first flatus was 1 day (range 0-15). Median time to defecation was 3 days (range 0-16 days). Twenty-three patients (28%) experienced prolonged ileus. There was a significant longer time to first defecation for patients who received a VRAM flap (P = 0.046). There was also a significant association between longer operative times and first flatus (P = 0.007). This retrospective study reveals that POI remains as a significant clinical problem in patients undergoing advanced pelvic cancer surgery, despite the increased awareness and implementation of enhanced recovery protocols. New regimens for better prophylaxis are needed, and further research on POI treatment is important. Copyright © 2017 Elsevier Inc. All rights reserved.

Preliminary Benefits Assessment of Traffic Aware Strategic Aircrew Requests (TASAR)

NASA Technical Reports Server (NTRS)

Henderson, Jeff; Idris, Husni; Wing, David J.

2012-01-01

While en route, aircrews submit trajectory change requests to air traffic control (ATC) to better meet their objectives including reduced delays, reduced fuel burn, and passenger comfort. Aircrew requests are currently made with limited to no information on surrounding traffic. Consequently, these requests are uninformed about a key ATC objective, ensuring traffic separation, and therefore less likely to be accepted than requests informed by surrounding traffic and that avoids creating conflicts. This paper studies the benefits of providing aircrews with on-board decision support to generate optimized trajectory requests that are probed and cleared of known separation violations prior to issuing the request to ATC. These informed requests are referred to as traffic aware strategic aircrew requests (TASAR) and leverage traffic surveillance information available through Automatic Dependent Surveillance Broadcast (ADS-B) In capability. Preliminary fast-time simulation results show increased benefits with longer stage lengths since beneficial trajectory changes can be applied over a longer distance. Also, larger benefits were experienced between large hub airports as compared to other airport sizes. On average, an aircraft equipped with TASAR reduced its travel time by about one to four minutes per operation and fuel burn by about 50 to 550 lbs per operation depending on the objective of the aircrew (time, fuel, or weighted combination of time and fuel), class of airspace user, and aircraft type. These preliminary results are based on analysis of approximately one week of traffic in July 2012 and additional analysis is planned on a larger data set to confirm these initial findings.

Test Plans and Procedures for the Baseline SAF for BDS-D Sites (ModSAF). Volume 2

DTIC Science & Technology

1993-12-20

operations editor will no longer editor, appear in the EditorI Area. 64 I ADST/WDL/TR-93-W003271 VOLUME 2 of 2; Ver 1.0I 44200 Repeat steps 44120 thru...The unit operations 44200 to task the orange editor will no longer platoon to Move on the appear in the Editor route labeled "ort. Area. The vehicles

Impact of backwashing procedures on deep bed filtration productivity in drinking water treatment.

PubMed

Slavik, Irene; Jehmlich, Alexander; Uhl, Wolfgang

2013-10-15

Backwash procedures for deep bed filters were evaluated and compared by means of a new integrated approach based on productivity. For this, different backwash procedures were experimentally evaluated by using a pilot plant for direct filtration. A standard backwash mode as applied in practice served as a reference and effluent turbidity was used as the criterion for filter run termination. The backwash water volumes needed, duration of the filter-to-waste period, time out of operation, total volume discharged and filter run-time were determined and used to calculate average filtration velocity and average productivity. Results for filter run-times, filter backwash volumes, and filter-to-waste volumes showed considerable differences between the backwash procedures. Thus, backwash procedures with additional clear flushing phases were characterised by an increased need for backwash water. However, this additional water consumption could not be compensated by savings during filter ripening. Compared to the reference backwash procedure, filter run-times were longer for both single-media and dual-media filters when air scour and air/water flush were optimised with respect to flow rates and the proportion of air and water. This means that drinking water production time is longer and less water is needed for filter bed cleaning. Also, backwashing with additional clear flushing phases resulted in longer filter run-times before turbidity breakthrough. However, regarding the productivity of the filtration process, it was shown that it was almost the same for all of the backwash procedures investigated in this study. Due to this unexpected finding, the relationships between filter bed cleaning, filter ripening and filtration performance were considered and important conclusions and new approaches for process optimisation and resource savings were derived. Copyright © 2013 Elsevier Ltd. All rights reserved.

Phosphorus removal from aquaculture effluents at the Northeast Fishery Center in Lamar, Pennsylvania using iron oxide sorption media

USGS Publications Warehouse

Sibrell, Philip; Kehler, Thomas

2016-01-01

Three different iron oxide-based sorption media samples were tested for removal of phosphorus (P) from fish hatchery effluents using fixed bed processing. Two of the media samples were derived from residuals produced by the treatment of acid mine drainage, which were then compared to granular ferric hydroxide (GFH), a commercially available sorption medium. All of the media types removed from 50 to 70% of the P from the incoming aquaculture wastewater over 70–175 days of operation without regeneration. In some of the sorption trials, the GFH media showed superior adsorption in the earlier stages of the trial, but the GFH appeared to reach saturation more quickly, so that media performance was similar – at about 60% removal of P – over a longer time period of 175 days. Media regeneration tests were also conducted for both the commercial and mine drainage media, and demonstrated longer term performance, with overall P removal of 50–55%, over 223 days of total operation, with the advantages of phosphorus recycle and media reuse.

A financial analysis of revision hip arthroplasty: the economic burden in relation to the national tariff.

PubMed

Vanhegan, I S; Malik, A K; Jayakumar, P; Ul Islam, S; Haddad, F S

2012-05-01

Revision arthroplasty of the hip is expensive owing to the increased cost of pre-operative investigations, surgical implants and instrumentation, protracted hospital stay and drugs. We compared the costs of performing this surgery for aseptic loosening, dislocation, deep infection and peri-prosthetic fracture. Clinical, demographic and economic data were obtained for 305 consecutive revision total hip replacements in 286 patients performed at a tertiary referral centre between 1999 and 2008. The mean total costs for revision surgery in aseptic cases (n = 194) were £11 897 (sd 4629), for septic revision (n = 76) £21 937 (sd 10 965), for peri-prosthetic fracture (n = 24) £18 185 (sd 9124), and for dislocation (n = 11) £10 893 (sd 5476). Surgery for deep infection and peri-prosthetic fracture was associated with longer operating times, increased blood loss and an increase in complications compared to revisions for aseptic loosening. Total inpatient stay was also significantly longer on average (p < 0.001). Financial costs vary significantly by indication, which is not reflected in current National Health Service tariffs.

The Analysis of Electrical Energy Consumption of the Impact Screwdriver During Assembly of Fixed Threaded Joints

NASA Astrophysics Data System (ADS)

Grinevich, I.; Nikishin, Vl.; Mozga, N.; Laitans, M.

2017-06-01

The paper deals with the possibilities of reducing the consumption of electrical energy of the impact screwdriver during the assembly of fixed threaded joints. The recommendations related to a decrease in electrical energy consumption would allow reducing product costs but so far there have been no such recommendations from the producers of the tool as to the effective operating regimes of the impact screwdrivers in relation to electrical energy consumption and necessary tightening moment of the nut. The aim of the study is to find out the economical operating mode of the electrical impact screwdriver when assembling fixed threaded joints. By varying the set speed of the rotor head and working time of the impact mechanism, there is an opportunity to determine electrical energy consumption of the tool for the given tightening moment. The results of the experiment show that at the same tightening moment obtained the electrical energy consumption of the impact screwdriver is less at a higher starting set speed of the rotor head but shorter operating time of the impact mechanism than at a lower speed of the rotor head and longer operating time of the impact mechanism.

Identifying Best Bet Entry-Level Selection Measures for US Air Force Remotely Piloted Aircraft (RPA) Pilot and Sensor Operator (SO) Occupations

DTIC Science & Technology

2011-12-01

Institute for the Behavioral and Social Sciences. Fishbein , M ., & Ajzen , I . (1975). Belief, attitude, intention, and behavior: An introduction...behavior than are opinions ( Fishbein & Ajzen , 1975). Of course the longer the time between when applicants complete this measure and when they express a...R. & Garland, D. J. ( 2000 ). Situation Awareness Analysis and Measurement. Mahwah, NJ. Lawrence Erlbaum. Endsley, M . R. (1990). Predictive

Robotic Versus Laparoscopic Bariatric Surgery: a Systematic Review and Meta-Analysis.

PubMed

Li, Kun; Zou, Jianan; Tang, Jianxiong; Di, Jianzhong; Han, Xiaodong; Zhang, Pin

2016-12-01

We aim to summarize the available literature on patients treated with robotic bariatric surgery (RBS) or laparoscopic bariatric surgery (LBS) and compare the clinical outcomes between RBS and LBS. A systematic literature was conducted in accordance with the PRISMA guidelines. Thirty-four observational studies met our inclusion criteria, and 27 studies of 27,997 patients were included in the meta-analysis. There were no significant differences between RBS and LBS regarding overall postoperative complications, major complications, the length of hospital stay, reoperation, conversion, and mortality. Nevertheless, RBS was burdened by longer operative times and higher hospital costs when compared with LBS. On the contrary, the incidence of anastomotic leak was lower in RBS than in LBS. Further studies with a longer follow-up are recommended.

Expanded interleaved solid-state memory for a wide bandwidth transient waveform recorder

NASA Technical Reports Server (NTRS)

Thomas, R. M., Jr.

1980-01-01

An interleaved, solid state expanded memory for a 100 MHz bandwidth waveform recorder is described. The memory development resulted in a significant increase in the storage capacity of a commercially available recorder. The motivation for the memory expansion of the waveform recorder, which is used to support in-flight measurement of the electromagnetic characteristics of lightning discharges, was the need for a significantly longer data window than that provided by the commercially available unit. The expanded recorder provides a data window that is 128 times longer than the commercial unit, while maintaining the same time resolution, by increasing the storage capacity from 1024 to 131 072 data samples. The expanded unit operates at sample periods as small as 10 ns. Sampling once every 10 ns, the commercial unit records for about 10 microseconds before the memory is filled, whereas, the expanded unit records for about 1300 microseconds. A photo of the expanded waveform recorder is shown.

A Comparison of Single-, Two- and Three-Port Laparoscopic Myomectomy

PubMed Central

Kim, Su Mi; Baek, Jong Min; Park, Eun Kyung; Jeung, In Cheul; Choi, Ji Hyang; Kim, Chan Joo

2015-01-01

Background and Objective: A recent FDA safety communication has discouraged the use of a power morcellator for myoma extraction and has called for a change in surgical techniques for myomectomy. The objective of this study was to compare surgical outcomes of laparoscopic single-, two-, and conventional three-port myomectomy and to evaluate the feasibility of contained manual morcellation for uterine myoma. Methods: This retrospective study was a review and analysis of data from 191 consecutive women who underwent single-, two-, or three-port myomectomy for the management of uterine myoma from January 1, 2009, through December 31, 2014. Results: The 3 study groups did not differ demographically. Apart from operative time, the single- and two-port groups showed operative outcomes comparable to those of the multiport group. The single-port group had significantly longer operative times (P = .0053) than the two- and three-port groups. However, in the latter half of the single-port cases, the operative time was similar to those in the three-port group. The two-port surgery group showed a consistent operative time without a learning period. Conclusion: Single- or two-port myomectomy with transumbilical myoma morcellation is feasible and safe, with outcomes comparable to those of three-port myomectomy. These results suggest the potential for minimally invasive management of symptomatic uterine myoma, without the use of a power morcellator. PMID:26648680

A meta-analysis of laparoscopic versus open appendectomy in patients suspected of having acute appendicitis

PubMed Central

Temple, Larissa K.F.; Litwin, Demetrius E.; McLeod, Robin S.

Objective To determine if any significant differences exist between laparoscopic appendectomy (LA) and open appendectomy (OA). Design A meta-analysis of randomized controlled trials (RCTs) comparing LA to OA. Data sources An extensive literature search was conducted for appropriate articles published between January 1990 and March 1997. Articles were initially retrieved through MEDLINE with MeSH terms “appendicitis” or “appendectomy” and “laparoscopy.” Additional methods included cross-referencing bibliographies of retrieved articles, hand searching abstracts from relevant meetings and consultation with a content expert. Study selection Only RCTs published in English in which patients had a preoperative diagnosis of acute appendicitis were included. Data extraction The outcomes of interest included operating time, hospital stay, readmission rates, return to normal activity and complications. The Cochrane Collaboration Review Manager 3.0 was used to calculate odds ratios (OR), weighted mean differences (WMD) and 95% confidence intervals (CI). The random-effects model was used for statistical analysis. Data synthesis Twelve trials met the inclusion criteria. Because there were insufficient data in some trials, operating time, hospitalization and return to work were assessed in only 8 trials. Mean operating time was significantly longer with LA (WMD 18.10 minutes, 95% CI 12.87 to 23.15 minutes). There were fewer wound infections in LA (OR 0.40, 95% CI 0.24 to 0.69), but no significant differences in intra-abdominal abscess rates (OR 1.94, 95% CI 0.68 to 5.58). There was no significant difference in the mean length of hospital stay (WMD −0.16 days, 95% CI −0.44 to 0.15 days) or readmission rates (OR 1.16, 95% CI 0.54 to 2.48). However, the return to normal activity was significantly earlier with LA (WMD −5.79 days, 95% CI −7.38 to −4.21 days). Sensitivity analyses did not affect the results. Conclusion This meta-analysis suggests that operating room time is significantly longer, hospital stay is unchanged but return to normal activities is significantly earlier with LA. PMID:10526524

Introduction of laparoscopic low anterior resection for rectal cancer early during residency: a single institutional study on short-term outcomes.

PubMed

Ogiso, Satoshi; Yamaguchi, Takashi; Hata, Hiroaki; Kuroyanagi, Hiroya; Sakai, Yoshiharu

2010-11-01

Laparoscopic surgery for rectal cancer is unpopular because it is technically challenging. Suitable training systems have not been widely studied or established despite the steep learning curve for this procedure. We developed a systematic training program that enables resident surgeons to perform laparoscopic low anterior resection (LLAR) for rectal cancer and evaluated the safety and feasibility of this training program. We analyzed prospectively gathered data on all LLARs for rectal cancer performed at a single center over a 7-year period. Patients were assessed for demographic characteristics, tumor characteristics, operative procedure, operative time, blood loss, conversion to open surgery, complications, time to bowel recovery, distal margin, and number of lymph nodes harvested. We compared the early surgical, oncological, and functional outcomes of LLARs performed by expert surgeons with those of LLARs performed by resident surgeons for both intraperitoneal and extraperitoneal rectal cancer. All analyses were performed on an intention-to-treat basis. A total of 137 patients met the inclusion criteria for this study. Of the 75 LLARs for intraperitoneal rectal cancer, 40 were performed by expert surgeons (I-E group) and 35 by resident surgeons (I-R group). Of the 62 LLARs for extraperitoneal rectal cancer, 51 were performed by expert surgeons (E-E group) and 11 by resident surgeons (E-R group). The operative time was longer in the E-R group than in the E-E group. The time to resumption of diet was longer in the I-E group than in the I-R group. The other early outcomes, including blood loss, anastomotic leakage, conversion to open surgery, and number of lymph nodes harvested, were similar in the I-E and I-R groups and in the E-E and E-R groups. Our systematic training program on LLAR for rectal cancer enables resident surgeons to perform this procedure safely early during residency, with acceptable short-term outcomes.

Totally extraperitoneal inguinal hernia repair in patients previously having prostatectomy is feasible, safe, and effective.

PubMed

Le Page, Philip; Smialkowski, Ania; Morton, Jonathan; Fenton-Lee, Douglas

2013-12-01

The laparoscopic approach to repair of inguinal hernia has proven advantages over open repair. Repair of more technically challenging hernias, such as patients previously receiving prostatectomy, has been less studied and may not have these advantages. We aimed to compare safety, feasibility, and clinical outcomes for repairs in patients who previously underwent prostatectomy to control subjects. We undertook a case-control study using a prospectively collected database. From 2004, all patients were routinely offered totally extraperitoneal laparoscopic repair. All patients who had a history of previous prostatectomy were identified and compared to a matched control group. Both operative and follow-up data were analyzed. Of 987 patients undergoing surgery during this time period, 52 prostatectomy patients were identified (44% open, 44% robotic, 3% laparoscopic) and matched to 102 control subjects. Accounting for bilateral repairs, 203 hernia repairs had been performed. Patients were well matched for age and American Society of Anesthesiologists score. Operative time was longer for prostatectomy patients (mean, 70 vs. 52 min, p < 0.0001); however, this reduced over time when comparing the first and second half prostatectomy patients (77 vs. 63 min, p = 0.144). Overall, there were no intraoperative or major postoperative complications and only one conversion (prostatectomy group). No significant differences were found for rates of minor postoperative complications, length of stay, or recurrence (n = 1, control group). No difference was observed for chronic pain, and all patients in each group reported satisfaction with surgery at contemporary follow-up. In experienced hands, totally extraperitoneal inguinal hernia repair for patients previously having undergone prostatectomy is safe and has equivalent outcomes to patients not having undergone prostatectomy, and is an option to open repair. Understandably, slightly longer operative times may be justified, given the benefits of early discharge and less postoperative pain after laparoscopic surgery.

Impact of a Disposable Sterile Radiation Shield on Operator Radiation Exposure During Percutaneous Coronary Intervention of Chronic Total Occlusions.

PubMed

Shorrock, Deborah; Christopoulos, Georgios; Wosik, Jedrek; Kotsia, Anna; Rangan, Bavana; Abdullah, Shuaib; Cipher, Daisha; Banerjee, Subhash; Brilakis, Emmanouil S

2015-07-01

Daily radiation exposure over many years can adversely impact the health of medical professionals. Operator radiation exposure was recorded for 124 percutaneous coronary interventions (PCIs) performed at our institution between August 2011 and May 2013: 69 were chronic total occlusion (CTO)-PCIs and 55 were non-CTO PCIs. A disposable radiation protection sterile drape (Radpad; Worldwide Innovations & Technologies, Inc) was used in all CTO-PCI cases vs none of the non-CTO PCI cases. Operator radiation exposure was compared between CTO and non-CTO PCIs. Mean age was 64.6 ± 6.2 years and 99.2% of the patients were men. Compared with non-CTO PCI, patients undergoing CTO-PCI were more likely to have congestive heart failure, to be current smokers, and to have longer lesions, and less likely to have prior PCI and a saphenous vein graft target lesion. CTO-PCI cases had longer procedural time (median: 123 minutes [IQR, 85-192 minutes] vs 27 minutes [IQR, 20-44 minutes]; P<.001), fluoroscopy time (35 minutes [IQR, 19-54 minutes] vs 8 minutes [IQR, 5-16 minutes]; P<.001), number of stents placed (2.4 ± 1.5 vs 1.7 ± 0.9; P<.001), and patient air kerma radiation exposure (3.92 Gray [IQR, 2.48-5.86 Gray] vs 1.22 Gray [IQR, 0.74-1.90 Gray]; P<.001), as well as dose area product (267 Gray•cm² [IQR, 163-4.25 Gray•cm²] vs 84 Gray•cm² [IQR, 48-138 Gray•cm²]; P<.001). In spite of higher patient radiation exposure, operator radiation exposure was similar between the two groups (20 μSv [IQR, 9.5-31 μSv] vs 15 μSv [IQR, 7-23 μSv]; P=.07). Operator radiation exposure during CTO-PCI can be reduced to levels similar to less complicated cases with the use of a disposable sterile radiation protection shield.

Does Wait-List Size at Registration Influence Time to Surgery? Analysis of a Population-Based Cardiac Surgery Registry

PubMed Central

Sobolev, Boris; Levy, Adrian; Hayden, Robert; Kuramoto, Lisa

2006-01-01

Objective To determine whether the probability of undergoing coronary bypass surgery within a certain time was related to the number of patients on the wait list at registration for the operation in a publicly funded health system. Methods A prospective cohort study comparing waiting times among patients registered on wait lists at the hospitals delivering adult cardiac surgery. For each calendar week, the list size, the number of new registrations, and the number of direct admissions immediately after angiography characterized the demand for surgery. Results The length of delay in undergoing treatment was associated with list size at registration, with shorter times for shorter lists (log-rank test 1,198.3, p<.0001). When the list size at registration required clearance time over 1 week patients had 42 percent lower odds of undergoing surgery compared with lists with clearance time less than 1 week (odds ratio [OR] 0.58 percent, 95 percent, confidence interval [CI] 0.53–0.63), after adjustment for age, sex, comorbidity, period, and hospital. The weekly number of new registrations exceeding weekly service capacity had an independent effect toward longer service delays when the list size at registration required clearance time less than 1 week (OR 0.56 percent, 95 percent CI 0.45–0.71), but not for longer lists. Every time the operation was performed for a patient requiring surgery without registration on wait lists, the odds of surgery for listed patients were reduced by 6 percent (OR 0.94, CI 0.93–0.95). Conclusion For wait-listed patients, time to surgery depends on the list size at registration, the number of new registrations, as well as on the weekly number of patients who move immediately from angiography to coronary bypass surgery without being registered on a wait list. Hospital managers may use these findings to improve resource planning and to reduce uncertainty when providing advice on expected treatment delays. PMID:16430599

[Comparative analysis of mechanical and manual cervical esophagogastric anastomosis following esophagectomy for esophageal cancer].

PubMed

Cayi, Ruijun; Li, Mei; Xiong, Gang; Cai, Kaican; Wang, Wujun

2012-06-01

To compare the complications associated with mechanical and manual cervical esophagogastric anastomosis following esophagectomy for esophageal cancer. From September, 2004 to June, 2007, 227 patients with middle and upper thoracic esophageal cancer underwent cervical esophagogastric anastomosis after esophagectomy. The patients were randomized into two groups and cervical esophagogastric anastomosis was performed using a stapler (n=102) or manually (n=125). The incidence of postoperative complications and operative time were compared between the two groups. In manual anastomosis group, anastomotic leak and anastomotic stricture occurred in 14.4% (18/125) and 8.8.% (11/125) of the patients, significantly higher than the incidences of 2.9% (3/102) and 3.9% (4/102) in the mechanical anastomosis group (P<0.01). Manual anastomosis required a significantly longer operative time than mechanical anastomosis (52∓12 vs 25∓5 min, P<0.01). The use of circular mechanical stapler in cervical esophagogastric anastomosis is associated with a lower rate of anastomotic leak and a shorter operative time, and is easy to learn and standardize to reduce the complications of the anastomosis.

Estimating time-dependent ROC curves using data under prevalent sampling.

PubMed

Li, Shanshan

2017-04-15

Prevalent sampling is frequently a convenient and economical sampling technique for the collection of time-to-event data and thus is commonly used in studies of the natural history of a disease. However, it is biased by design because it tends to recruit individuals with longer survival times. This paper considers estimation of time-dependent receiver operating characteristic curves when data are collected under prevalent sampling. To correct the sampling bias, we develop both nonparametric and semiparametric estimators using extended risk sets and the inverse probability weighting techniques. The proposed estimators are consistent and converge to Gaussian processes, while substantial bias may arise if standard estimators for right-censored data are used. To illustrate our method, we analyze data from an ovarian cancer study and estimate receiver operating characteristic curves that assess the accuracy of the composite markers in distinguishing subjects who died within 3-5 years from subjects who remained alive. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Tracking performance under time sharing conditions with a digit processing task: A feedback control theory analysis. [attention sharing effect on operator performance

NASA Technical Reports Server (NTRS)

Gopher, D.; Wickens, C. D.

1975-01-01

A one dimensional compensatory tracking task and a digit processing reaction time task were combined in a three phase experiment designed to investigate tracking performance in time sharing. Adaptive techniques, elaborate feedback devices, and on line standardization procedures were used to adjust task difficulty to the ability of each individual subject and manipulate time sharing demands. Feedback control analysis techniques were employed in the description of tracking performance. The experimental results show that when the dynamics of a system are constrained, in such a manner that man machine system stability is no longer a major concern of the operator, he tends to adopt a first order control describing function, even with tracking systems of higher order. Attention diversion to a concurrent task leads to an increase in remnant level, or nonlinear power. This decrease in linearity is reflected both in the output magnitude spectra of the subjects, and in the linear fit of the amplitude ratio functions.

Learning curves for single incision and conventional laparoscopic right hemicolectomy: a multidimensional analysis.

PubMed

Park, Yoonah; Yong, Yuen Geng; Yun, Seong Hyeon; Jung, Kyung Uk; Huh, Jung Wook; Cho, Yong Beom; Kim, Hee Cheol; Lee, Woo Yong; Chun, Ho-Kyung

2015-05-01

This study aimed to compare the learning curves and early postoperative outcomes for conventional laparoscopic (CL) and single incision laparoscopic (SIL) right hemicolectomy (RHC). This retrospective study included the initial 35 cases in each group. Learning curves were evaluated by the moving average of operative time, mean operative time of every five consecutive cases, and cumulative sum (CUSUM) analysis. The learning phase was considered overcome when the moving average of operative times reached a plateau, and when the mean operative time of every five consecutive cases reached a low point and subsequently did not vary by more than 30 minutes. Six patients with missing data in the CL RHC group were excluded from the analyses. According to the mean operative time of every five consecutive cases, learning phase of SIL and CL RHC was completed between 26 and 30 cases, and 16 and 20 cases, respectively. Moving average analysis revealed that approximately 31 (SIL) and 25 (CL) cases were needed to complete the learning phase, respectively. CUSUM analysis demonstrated that 10 (SIL) and two (CL) cases were required to reach a steady state of complication-free performance, respectively. Postoperative complications rate was higher in SIL than in CL group, but the difference was not statistically significant (17.1% vs. 3.4%). The learning phase of SIL RHC is longer than that of CL RHC. Early oncological outcomes of both techniques were comparable. However, SIL RHC had a statistically insignificant higher complication rate than CL RHC during the learning phase.

Development and Testing of Operational Dual-Polarimetric Radar Based Lightning Initiation Forecast Techniques

NASA Technical Reports Server (NTRS)

Woodard, Crystal; Carey, Lawrence D.; Petersen, Walter A.; Felix, Mariana; Roeder, William P.

2011-01-01

Lightning is one of Earth s natural dangers, destructive not only to life but also physical property. According to the National Weather Service, there are on average 58 lightning fatalities each year, with over 300 related injuries (NWS 2010). The ability to forecast lightning is critical to a host of activities ranging from space vehicle launch operations to recreational sporting events. For example a single lightning strike to a Space Shuttle could cause billions of dollars of damage and possible loss of life. While forecasting that provides longer lead times could provide sporting officials with more time to respond to possible threatening weather events, thus saving the lives of player and bystanders. Many researchers have developed and tested different methods and tools of first flash forecasting, however few have done so using dual-polarimetric radar variables and products on an operational basis. The purpose of this study is to improve algorithms for the short-term prediction of lightning initiation through development and testing of operational techniques that rely on parameters observed and diagnosed using C-band dual-polarimetric radar.

Fuel cycle cost reduction through Westinghouse fuel design and core management

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

Frank, F.J.; Scherpereel, L.R.

1985-11-01

This paper describes advances in Westinghouse nuclear fuel and their impact on fuel cycle cost. Recent fabrication development has been aimed at maintaining high integrity, increased operating flexibility, longer operating cycles, and improved core margins. Development efforts at Westinghouse toward meeting these directions have culminated in VANTAGE 5 fuel. The current trend toward longer operating cycles provides a further driving force to minimize the resulting inherent increase in fuel cycle costs by further increases in region discharge burnup. Westinghouse studies indicate the capability of currently offered products to meet cycle lengths up to 24 months.

A vacuum-operated pore-water extractor for estuarine and freshwater sediments

USGS Publications Warehouse

Winger, Parley V.; Lasier, Peter J.

1991-01-01

A vacuum-operated pore-water extractor for estuarine and freshwater sediments was developed and constructed from a fused-glass air stone attached with aquarium airline tubing to a 30 or 60 cc polypropylene syringe. Pore water is extracted by inserting the air stone into the sediment and creating a vacuum by retracting and bracing the syringe plunger. A hand-operated vacuum pump attached to a filtration flask was also evaluated as an alternative vacuum source. The volume and time to extract pore water varies with the number of devices and the sediment particle size. Extraction time is longer for fine sediments than for sandy sediments. Four liters of sediment generally yield between 500 and 1,500 mL of pore water. The sediment that surrounds and accumulates on the air stone acts as a filter, and, except for the first few milliliters, the collected pore water is clear. Because there is no exposure to air or avenue for escape, volatile compounds andin situ characteristics are retained in the extracted pore water.

The Effect of Afternoon Operative Sessions of Laparoscopic Cholecystectomy Performed by Senior Surgeons on the General Surgery Residency Program: A Comparative Study.

PubMed

Lavy, Ron; Halevy, Ariel; Hershkovitz, Yehuda

2015-01-01

Laparoscopic cholecystectomy (LC) has been the gold standard for surgical treatment of gallbladder disease since 1980. This laparoscopic surgical procedure is one of the first to be performed by general surgery residents. There is a learning curve required to excel at performing LC. During this period, the operation needs to be performed under the supervision of a senior surgeon. The purpose of this study was to compare LC performed by residents with that performed by senior surgeons using the following parameters: operative time, conversion rate, complication rate, and mean length of hospital stay. This retrospective study included 1219 patients who underwent elective LC in our institute-788 operated on by a senior surgeon and 431 by a resident. The mean operative time was 39 ± 19 minutes. There was a significant difference between the groups, as the mean operative time for the resident group was 49.9 ± 13 compared with 33.7 ± 6 for the senior surgeon group. The overall conversion rate was 2.1%, the complication rate was 2.2%, and the mean length of hospital stay was 1.5 days. There were no statistically significant differences between the groups for these parameters. The only significant difference between the groups was a longer operative time, as the conversion rate, complication rate, and mean length of stay were the same. Therefore, it is safe for LC to be performed by residents supervised by a senior surgeon. Copyright © 2015. Published by Elsevier Inc.

Tracking the time course of multi-word noun phrase production with ERPs or on when (and why) cat is faster than the big cat.

PubMed

Bürki, Audrey; Laganaro, Marina

2014-01-01

Words are rarely produced in isolation. Yet, our understanding of multi-word production, and especially its time course, is still rather poor. In this research, we use event-related potentials to examine the production of multi-word noun phrases in the context of overt picture naming. We track the processing costs associated with the production of these noun phrases as compared with the production of bare nouns, from picture onset to articulation. Behavioral results revealed longer naming latencies for French noun phrases with determiners and pre-nominal adjectives (D-A-N, the big cat) than for noun phrases with a determiner (D-N, the cat), or bare nouns (N, cat). The spatio-temporal analysis of the ERPs revealed differences in the duration of stable global electrophysiological patterns as a function of utterance format in two time windows, from ~190 to 300 ms after picture onset, and from ~530 ms after picture onset to 100 ms before articulation. These findings can be accommodated in the following model. During grammatical encoding (here from ~190 to 300 ms), the noun and adjective lemmas are accessed in parallel, followed by the selection of the gender-agreeing determiner. Phonological encoding (after ~530 ms) operates sequentially. As a consequence, the phonological encoding process is longer for longer utterances. In addition, when determiners are repeated across trials, their phonological encoding can be anticipated or primed, resulting in a shortened encoding process.

Optimization of antibacterial activity by Gold-Thread (Coptidis Rhizoma Franch) against Streptococcus mutans using evolutionary operation-factorial design technique.

PubMed

Choi, Ung-Kyu; Kim, Mi-Hyang; Lee, Nan-Hee

2007-11-01

This study was conducted to find the optimum extraction condition of Gold-Thread for antibacterial activity against Streptococcus mutans using The evolutionary operation-factorial design technique. Higher antibacterial activity was achieved in a higher extraction temperature (R2 = -0.79) and in a longer extraction time (R2 = -0.71). Antibacterial activity was not affected by differentiation of the ethanol concentration in the extraction solvent (R2 = -0.12). The maximum antibacterial activity of clove against S. mutans determined by the EVOP-factorial technique was obtained at 80 degrees C extraction temperature, 26 h extraction time, and 50% ethanol concentration. The population of S. mutans decreased from 6.110 logCFU/ml in the initial set to 4.125 logCFU/ml in the third set.

A probabilistic approach to information retrieval in heterogeneous databases

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

Chatterjee, A.; Segev, A.

During the post decade, organizations have increased their scope and operations beyond their traditional geographic boundaries. At the same time, they have adopted heterogeneous and incompatible information systems independent of each other without a careful consideration that one day they may need to be integrated. As a result of this diversity, many important business applications today require access to data stored in multiple autonomous databases. This paper examines a problem of inter-database information retrieval in a heterogeneous environment, where conventional techniques are no longer efficient. To solve the problem, broader definitions for join, union, intersection and selection operators are proposed.more » Also, a probabilistic method to specify the selectivity of these operators is discussed. An algorithm to compute these probabilities is provided in pseudocode.« less

Bridging the Economic Development Gap: Establishing a Practical Military Expeditionary Economics Continuum

DTIC Science & Technology

2013-04-05

59NGOs typically allow two weeks to one month before repayment begins, although longer time periods may be necessary. See Tillman Bruett et al ...D.C.: USAID, 2001), 1. 68Ibid, 3-4. 69Tillman Bruett et al ., Conflict and Post-Conflict Environments: Ten Short Lessons to make Microfinance Work...Germany to Iraq, by James Dobbins, et al ., 25-53. Santa Monica,CA: RAND Publications, 2005, 39. 4 Timothy Nourse, "Refuge to Return: Operational

Proceedings, Annual Meeting (27th), Aquatic Plant Control Research Program Held in Bellevue, Washington on 16-19 November 1992

DTIC Science & Technology

1993-09-01

plants, longer exposure times, and consider- tive species. ation of seasonal/phenological cycles. Design features and operating characteristics of the In...attached to the stem near the apex. temperature when pupation and active feeding The case is a useful diagnostic feature for starts. Overwintering...larvae were located on identification. Other morphological features milfoil shoots in an inactive state throughout Proceedngs, 27th Annual Meeting, APCRP

Regime-dependence of Impacts of Radar Rainfall Data Assimilation

NASA Astrophysics Data System (ADS)

Craig, G. C.; Keil, C.

2009-04-01

Experience from the first operational trials of assimilation of radar data in kilometre scale numerical weather prediction models (operating without cumulus parameterisation) shows that the positive impact of the radar data on convective precipitation forecasts typically decay within a few hours, although certain cases show much longer impacts. Here the impact time of radar data assimilation is related to characteristics of the meteorological environment. This QPF uncertainty is investigated using an ensemble of 10 forecasts at 2.8 km horizontal resolution based on different initial and boundary conditions from a global forecast ensemble. Control forecasts are compared with forecasts where radar reflectivity data is assimilated using latent heat nudging. Examination of different cases of convection in southern Germany suggests that the forecasts can be separated into two regimes using a convective timescale. Short impact times are associated with short convective timescales that are characteristic of equilibrium convection. In this regime the statistical properties of the convection are constrained by the large-scale forcing, and effects of the radar data are lost within a few hours as the convection rapidly returns to equilibrium. When the convective timescale is large (non-equilibrium conditions), the impact of the radar data is longer since convective systems are triggered by the latent heat nudging and are able to persist for many hours in the very unstable conditions present in these cases.

Pediatric appendicitis in a developing country: what are the clinical predictors and outcome of perforation?

PubMed

Ngim, Chin Fang; Quek, Kia Fatt; Dhanoa, Amreeta; Khoo, Joon Joon; Vellusamy, Muthualhagi; Ng, Chen Siew

2014-12-01

This study explored the risk factors and outcomes associated with perforation in children who underwent emergency appendicectomies. A retrospective cross-sectional study was conducted on children <13 years old who underwent appendicectomies in a Malaysian hospital in 2007. One hundred thirty-four children underwent appendicectomies of which 118 were confirmed histologically. Sixty-one (52%) were perforated. Children with perforation had significantly longer duration of symptoms (p < 0.001), higher white cell count and absolute neutrophil counts (p = 0.013), with longer intra-operative period (p < 0.001) and post-operative recovery period (p < 0.001). Of the 52 samples of pus collected intra-operatively, 37 (71.1%) yielded positive cultures that were predominantly Escherichia coli (n = 27). Both the patients who had Staphylococcus aureus cultured from pus collected intra-operatively had significant pyogenic complications (scrotal pyocele and intra-abdominal abscess). Children whose appendicitis were perforated had longer duration of symptoms, higher white cell counts and absolute neutrophil counts. Those with S.aureus cultured from intra-operative pus appeared to suffer more complications. © The Author [2014]. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Comparable operative times with and without surgery resident participation.

PubMed

Uecker, John; Luftman, Kevin; Ali, Sadia; Brown, Carlos

2013-01-01

Both physicians and patients may perceive that having surgical residents participate in operative procedures may prolong operations and worsen outcomes. We hypothesized that resident participation would prolong operative times and potentially adversely affect postoperative outcomes. To evaluate the effect of general surgery resident participation in surgical procedures on operative times and postoperative patient outcomes. Retrospective study of general surgery procedures performed during two 1-year time periods, 2007 without residents and 2011 with residents. Procedures included laparoscopic appendectomy and cholecystectomy, thyroidectomy, breast procedure, hernia repair, lower extremity amputation, tunneled venous catheter, and percutaneous endoscopic gastrostomy. The primary outcome was operative time and secondary outcomes included length of stay (LOS) and mortality. Academic general surgery residency program. There were 2280 operative procedures performed during the 2 periods: 1150 with resident involvement (RES group) and 1130 without residents (NORES group). The RES and NORES groups were similar for patient age (42 vs 41, p = 0.14) and male gender (46% vs 45%, p = 0.68), and there was no difference in overall operative time (68min vs 66min, p = 0.58). More specifically there was no difference in operative time (minutes) for specific procedures including laparoscopic appendectomy (67 vs 71, p = 0.8), thyroidectomy (125 vs 109, p = 0.16), breast procedure (38 vs 26, p = 0.79), hernia repair (61 vs 60, p = 0.74), lower extremity amputation (65 vs 77, p = 0.16), tunneled venous catheter (49 vs 47, p = 0.75), and percutaneous endoscopic gastrostomy (49 vs 46, p = 0.76). However, laparoscopic cholecystectomy took slightly longer in the RES group (71 vs 66, p = 0.02). LOS was shorter during the year with resident involvement (2.6 days vs 3.7 days, p = 0.0004) and there was no difference in mortality (0.17% vs 0.35%, p = 0.45). There is no difference in operative time for common general surgery procedures with or without resident involvement. In addition, resident involvement is associated with a decrease in LOS. This information should be used to change physician and patient negative perceptions regarding resident involvement while performing surgical procedures. © 2013 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

Are there any advantages in using a distal aiming device for tibial nailing? Comparing the Centro Nailing System with the Unreamed Tibia Nail.

PubMed

Veen, Egbert J D; Ettema, Harmen B; Zuurmond, Rutger G; Mostert, Adriaan K

2011-10-01

The distal locking of an intramedullary tibial nail can be challenging and time consuming when performed freehand. This study was conducted to evaluate if a distal aiming device would reduce surgical time. A case-controlled study was performed between 2007 and 2009 with 30 patients receiving a reamed tibial nail (Centronail) with the use of a distal aiming device and 30 patients who were treated with an Unreamed Tibia Nail (UTN), with freehand distal locking, in the same period. The primary outcome in this study was operative time. Secondary outcomes were the need for fluoroscopy, time to consolidation and complications. Operation time was longer in the Centronail group compared with the UTN group (126 min vs. 96 min, p=0.000). Use of fluoroscopy for distal locking was needed in half of the cases (n=16) using a distal aiming device. No differences were found regarding time to consolidation, time to removal of the nail and complications. The use of an aiming device for distal locking of a tibia nail lengthens operation time rather than reducing it. Fluoroscopy was still needed in about half of the cases. No difference was seen in clinical outcomes. The use of a distal aiming device to lock a tibial nail appears to have no benefit. Copyright © 2011 Elsevier Ltd. All rights reserved.

Initial results from the extreme ultraviolet explorer

NASA Technical Reports Server (NTRS)

Bowyer, S.; Malina, R. F.

1993-01-01

Data obtained during the first five months of calibration and science operation of the Extreme Ultraviolet Explorer (EUVE) are presented. Spectra of an extragalactic object were obtained; the object is detectable to wavelenghts longer than 100 A, demonstrating that extragalactic EUV astronomy is possible. Spectra of a hot white dwarf, and a late-type star in quiescence and flaring are shown as examples of the type of spectrographic data obtainable with EUVE. Other objects for which broad band photometric mode data have been obtained and analyzed include an RS CVn star and several late-type stars. The backgrounds in the EUVE detectors are quite low and the character of the diffuse astronomical EUV background has been investigated using these very low rates. Evidence is presented showing that, contrary to previously published reports, EUVE is about three times more sensitive than the English Wide Field Camera in the short wavelength bandpass covered by both instruments. Only limited information has been extracted from the longer bandpasses coered only by EUVE. Nonetheless, the brightest EUV source in the sky, a B star, has been discovered and is detected only in these longer bandpasses.

Design of the Extreme Ultraviolet Explorer long-wavelength grazing incidence telescope optics

NASA Technical Reports Server (NTRS)

Finley, David S.; Jelinsky, Patrick; Bowyer, Stuart; Malina, Roger F.

1988-01-01

Designing optics for photometry in the long-wavelength portion of the EUV spectrum (400-900) A) poses different problems from those arising for optics, operating shortward of 400 A. The available filter materials which transmit radiation longward of 400 A are also highly transparent at wavelengths shortward of 100 A. Conventional EUV optics, with grazing engles of less than about 10 deg, have very high throughput in the EUV, which persists to wavelengths shortward of 100 A. Use of such optics with the longer-wavelength EUV filters thus results in an unacceptably large soft X-ray leak. This problem is overcome by developing a mirror design with larger graze angles of not less than 20 deg, which has high throughput at wavelengths longer than 400 A but at the same time very little throughput shortward of 100 A.

Is Earth F**ked? Dynamical Futility of Global Environmental Management and Possibilities for Sustainability via Direct Action Activism

NASA Astrophysics Data System (ADS)

wErnEr, B.

2012-12-01

Environmental challenges are dynamically generated within the dominant global culture principally by the mismatch between short-time-scale market and political forces driving resource extraction/use and longer-time-scale accommodations of the Earth system to these changes. Increasing resource demand is leading to the development of two-way, nonlinear interactions between human societies and environmental systems that are becoming global in extent, either through globalized markets and other institutions or through coupling to global environmental systems such as climate. These trends are further intensified by dissipation-reducing technological advances in transactions, communication and transport, which suppress emergence of longer-time-scale economic and political levels of description and facilitate long-distance connections, and by predictive environmental modeling, which strengthens human connections to a short-time-scale virtual Earth, and weakens connections to the longer time scales of the actual Earth. Environmental management seeks to steer fast scale economic and political interests of a coupled human-environmental system towards longer-time-scale consideration of benefits and costs by operating within the confines of the dominant culture using a linear, engineering-type connection to the system. Perhaps as evidenced by widespread inability to meaningfully address such global environmental challenges as climate change and soil degradation, nonlinear connections reduce the ability of managers to operate outside coupled human-environmental systems, decreasing their effectiveness in steering towards sustainable interactions and resulting in managers slaved to short-to-intermediate-term interests. In sum, the dynamics of the global coupled human-environmental system within the dominant culture precludes management for stable, sustainable pathways and promotes instability. Environmental direct action, resistance taken from outside the dominant culture, as in protests, blockades and sabotage by indigenous peoples, workers, anarchists and other activist groups, increases dissipation within the coupled system over fast to intermediate scales and pushes for changes in the dominant culture that favor transition to a stable, sustainable attractor. These dynamical relationships are illustrated and explored using a numerical model that simulates the short-, intermediate- and long-time-scale dynamics of the coupled human-environmental system. At fast scales, economic and political interests exploit environmental resources through a maze of environmental management and resistance, guided by virtual Earth predictions. At intermediate scales, managers become slaved to economic and political interests, which adapt to and repress resistance, and resistance is guided by patterns of environmental destruction. At slow scales, resistance interacts with the cultural context, which co-evolves with the environment. The transition from unstable dynamics to sustainability is sensitively dependent on the level of participation in and repression of resistance. Because of their differing impact inside and outside the dominant culture, virtual Earth predictions can either promote or oppose sustainability. Supported by the National Science Foundation, Geomorphology and Land Use Dynamics Program.

The economic efficiency of allowing longer combination vehicles in Texas.

DOT National Transportation Integrated Search

2011-08-01

This paper shows the economic efficiency of allowing longer combination vehicles in Texas. First, an : overview of the truck size and weight policies is explained, with an emphasis on those that affect : Texas. Next, LCV operations in other countries...

VIPIC: a custom-made detector for X-ray speckle measurements

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

Rumaiz, Abdul K.; Siddons, D. Peter; Deptuch, Grzegorz

2016-03-01

The Vertically Integrated Photon Imaging Chip (VIPIC) was custom-designed for X-ray photon correlation spectroscopy, an application in which occupancy per pixel is low but high time resolution is needed. VIPIC operates in a sparsified streaming mode in which each detected photon is immediately read out as a time- and position-stamped event. This event stream can be fed directly to an autocorrelation engine or accumulated to form a conventional image. The detector only delivers non-zero data (sparsified readout), greatly reducing the communications overhead typical of conventional frame-oriented detectors such as charge-coupled devices or conventional hybrid pixel detectors. This feature allows continuousmore » acquisition of data with timescales from microseconds to hours. In this work VIPIC has been used to measure X-ray photon correlation spectroscopy data on polystyrene latex ano-colliodal suspensions in glycerol and on colloidal suspensions of silica spheres in water. Relaxation times of the nano-colloids have been measured for different temperatures. These results demonstrate that VIPIC can operate continuously in the microsecond time frame, while at the same time probing longer timescales.« less

First experimental feasibility study of VIPIC: a custom-made detector for X-ray speckle measurements

PubMed Central

Rumaiz, Abdul K.; Siddons, D. Peter; Deptuch, Grzegorz; Maj, Piotr; Kuczewski, Anthony J.; Carini, Gabriella A.; Narayanan, Suresh; Dufresne, Eric M.; Sandy, Alec; Bradford, Robert; Fluerasu, Andrei; Sutton, Mark

2016-01-01

The Vertically Integrated Photon Imaging Chip (VIPIC) was custom-designed for X-ray photon correlation spectroscopy, an application in which occupancy per pixel is low but high time resolution is needed. VIPIC operates in a sparsified streaming mode in which each detected photon is immediately read out as a time- and position-stamped event. This event stream can be fed directly to an autocorrelation engine or accumulated to form a conventional image. The detector only delivers non-zero data (sparsified readout), greatly reducing the communications overhead typical of conventional frame-oriented detectors such as charge-coupled devices or conventional hybrid pixel detectors. This feature allows continuous acquisition of data with timescales from microseconds to hours. In this work VIPIC has been used to measure X-ray photon correlation spectroscopy data on polystyrene latex nano-colliodal suspensions in glycerol and on colloidal suspensions of silica spheres in water. Relaxation times of the nano-colloids have been measured for different temperatures. These results demonstrate that VIPIC can operate continuously in the microsecond time frame, while at the same time probing longer timescales. PMID:26917126

Contemporary considerations in concurrent endoscopic sinus surgery and rhinoplasty.

PubMed

Steele, Toby O; Gill, Amarbir; Tollefson, Travis T

2018-06-11

Characterize indications, perioperative considerations, clinical outcomes and complications for concurrent endoscopic sinus surgery (ESS) and rhinoplasty. Chronic rhinosinusitis and septal deviation with or without inferior turbinate hypertrophy independently impair patient-reported quality of life. Guidelines implore surgeons to include endoscopy to accurately evaluate patient symptoms. Complication rates parallel those of either surgery (ESS and rhinoplasty) alone and are not increased when performed concurrently. Operative time is generally longer for joint surgeries. Patient satisfaction rates are high. Concurrent functional and/or cosmetic rhinoplasty and ESS is a safe endeavor to perform in a single operative setting and most outcomes data suggest excellent patient outcomes. Additional studies that include patient-reported outcome measures are needed.

Comparison of Lichtenstein inguinal hernia repair with the tension-free Desarda technique: a clinical audit and review of the literature.

PubMed

Zulu, Halalisani Goodman; Mewa Kinoo, Suman; Singh, Bhugwan

2016-07-01

Ours was a retrospective chart review of all elective open inguinal hernia repairs performed in a single unit at King Edward VIII Hospital, South Africa over an 18-month period. Comparison was made regarding duration of operation, length of hospital stay and complications such as pain, haematoma formation and recurrence between the Lichtenstein and Desarda techniques. The latter was noted to have a shorter operative time and avoided cost and possible complications of mesh usage, which are significant in resource-deprived settings. A larger comparative study with longer follow-up is needed to evaluate the wider suitability of the Desarda repair. © The Author(s) 2016.

Carbon Fiber Composites

NASA Technical Reports Server (NTRS)

1997-01-01

HyComp(R), Inc. development a line of high temperature carbon fiber composite products to solve wear problems in the harsh environment of steel and aluminum mills. WearComp(R), self-lubricating composite wear liners and bushings, combines carbon graphite fibers with a polyimide binder. The binder, in conjunction with the fibers, provides the slippery surface, one that demands no lubrication, yet wears at a very slow rate. WearComp(R) typically lasts six to ten times longer than aluminum bronze. Unlike bronze, WearComp polishes the same surface and imparts a self-lube film for years of service. It is designed for continuous operation at temperatures of 550 degrees Fahrenheit and can operate under high compressive loads.

Role of Pumped Storage Hydro Resources in Electricity Markets and System Operation: Preprint

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

Ela, E.; Kirby, B.; Botterud, A.

2013-05-01

The most common form of utility- sized energy storage system is the pumped storage hydro system. Originally, these types of storage systems were economically viable simply because they displace more expensive generating units. However, over time, as those expensive units became more efficient and costs declined, pumped hydro storage units no longer have the operational edge. As a result, in the current electricity market environment, pumped storage hydro plants are struggling. To offset this phenomenon, certain market modifications should be addressed. This paper will introduce some of the challenges faced by pumped storage hydro plants in today's markets and purposemore » some solutions to those problems.« less

Multigrid methods for differential equations with highly oscillatory coefficients

NASA Technical Reports Server (NTRS)

Engquist, Bjorn; Luo, Erding

1993-01-01

New coarse grid multigrid operators for problems with highly oscillatory coefficients are developed. These types of operators are necessary when the characters of the differential equations on coarser grids or longer wavelengths are different from that on the fine grid. Elliptic problems for composite materials and different classes of hyperbolic problems are practical examples. The new coarse grid operators can be constructed directly based on the homogenized differential operators or hierarchically computed from the finest grid. Convergence analysis based on the homogenization theory is given for elliptic problems with periodic coefficients and some hyperbolic problems. These are classes of equations for which there exists a fairly complete theory for the interaction between shorter and longer wavelengths in the problems. Numerical examples are presented.

Interpretation of digital breast tomosynthesis: preliminary study on comparison with picture archiving and communication system (PACS) and dedicated workstation.

PubMed

Kim, Young Seon; Chang, Jung Min; Yi, Ann; Shin, Sung Ui; Lee, Myung Eun; Kim, Won Hwa; Cho, Nariya; Moon, Woo Kyung

2017-08-01

To compare the diagnostic accuracy and efficiency in the interpretation of digital breast tomosynthesis (DBT) images using a picture archiving and communication system (PACS) and a dedicated workstation. 97 DBT images obtained for screening or diagnostic purposes were stored in both a workstation and a PACS and evaluated in combination with digital mammography by three independent radiologists retrospectively. Breast Imaging-Reporting and Data System final assessments and likelihood of malignancy (%) were assigned and the interpretation time when using the workstation and PACS was recorded. Receiver operating characteristic curve analysis, sensitivities and specificities were compared with histopathological examination and follow-up data as a reference standard. Area under the receiver operating characteristic curve values for cancer detection (0.839 vs 0.815, p = 0.6375) and sensitivity (81.8% vs 75.8%, p = 0.2188) showed no statistically significant differences between the workstation and PACS. However, specificity was significantly higher when analysing on the workstation than when using PACS (83.7% vs 76.9%, p = 0.009). When evaluating DBT images using PACS, only one case was deemed necessary to be reanalysed using the workstation. The mean time to interpret DBT images on PACS (1.68 min/case) was significantly longer than that to interpret on the workstation (1.35 min/case) (p < 0.0001). Interpretation of DBT images using PACS showed comparable diagnostic performance to a dedicated workstation, even though it required a longer reading time. Advances in knowledge: Interpretation of DBT images using PACS is an alternative to evaluate the images when a dedicated workstation is not available.

Retroperitoneal Varix ligation with sclerotherapy: a prospective randomized comparative study

PubMed Central

Abdelsalam, Yaser M.; Saeed, Waleed M.; Elganainy, Ehab O.; Ahmed, Abdelfatah I.

2017-01-01

Introduction The aim of this article is to compare the results of high varix ligation with and without sclerotherapy. Material and methods Between November 2014 and December 2015, sixty patients with varicocele were included in this study. Patients were divided into two equal groups; group I (underwent high varix ligation), and group II (underwent high varix ligation with a retrograde injection of 2 mL of 5% ethanolamine oleate in the lower end of the bisected gonadal vein). The operative time, intra- and postoperative complications, postoperative pain, improvement of semen parameters, incidence of recurrence and achieving of unassisted pregnancy were recorded for both groups. Results The age range was 19–34 years in group I and 21–37 years in group II. The operative time was shorter in group I (34.6 ±7.81 min) than group II (43.3 ±8.5 min) (P <0.001), which was statistically significant. Improvement of semen parameters and the occurrence of spontaneous pregnancy were insignificant between both groups. No intraoperative complications occurred. The postoperative complications were statistically insignificant in both groups. Conclusions Combined varix ligation with retrograde sclerotherapy does not offer significant advantages over high varix ligation alone with a longer operative time and prolonged post-operative pain. PMID:29104794

Operational Test Report (OTR): On-Site Degradation of Oily Sludge in a Tenthousand Gallon Sequencing Batch Reactor at Navsta Pearl Harbor, HI

DTIC Science & Technology

2003-11-01

treated anaerobically . To accommodate the longer residence times needed to treat waste anaerobically , the capacity is often much larger than a...the receiving tank (T1), where it is diluted and run through a trash pump (P1) to produce a homogenous slurry. 3 Figure 1. Sequencing...blower provides air to the reactor and receiving tank. The trash pump is also used to transfer sludge to the reactor and to recirculate sludge in

Electrospray of 1-Butyl-3-Methylimidazolium Dicyanamide Under Variable Flow Rate Operations

DTIC Science & Technology

2014-06-27

cm length. The capillary needle is stainless steel with a tapered tip of 50 μm inner diameter and 3.5 cm length. Both capillaries are commercially...connected. Figure 8 shows the emission current results of a 50 μm stainless - steel tip over the same IL flow rate range as Fig. 5. The emitter... fuming nitric acid, resulting in an ignition delay time of 47 ms, longer than the desired maximumof 5ms.Numerical predictions byBerg andRovey [18,19

To develop a spectral analyzer for physiological and medical use

NASA Technical Reports Server (NTRS)

Iberall, A.; Cardon, S.; Weinberg, M.; Schindler, A.

1971-01-01

Scientific requirements necessary to develop a spectral analyzer for monitoring mammalian subjects, are discussed. The analyzer measures dynamic or time dependent data as a measure of the subjects operating status. Measurable data include metabolic rate, body temperature, and blood constituents like glucose, oxygen, and carbon dioxide, and lactic acid. Metabolic cycles were found with periodicities in the range of minutes and hours; longer cycles in body weight (3 1/2 days and 60 days), indicative of metabolic processes, were also found.

The Global War on Terror: Mistaking Ideology as the Center of Gravity

DTIC Science & Technology

2005-07-01

worldwide effort that dismantled al-Qaeda’s central leadership global terrorism has mutated once again into a system of franchise operations.3 Al...Qaeda is no longer an organization; it is a brand name. Tony Karon noted in Time Magazine that “‘al-Qaeda,’ the name describes a broad franchise of...Report to Congress, February 10, 2005, 5. 3 A number of descriptive terms have been used in recent literature, but I attribute the term “ Franchise

Knee injuries related to sports in young adult males during military service - incidence and risk factors.

PubMed

Kuikka, P-I; Pihlajamäki, H K; Mattila, V M

2013-06-01

The population-based incidence and risk factors for knee injuries in young adults were assessed in Finnish male conscripts performing their compulsory military service (n = 128,584). The main outcome variables were (1) hospitalization due to knee injuries overall and (2) hospitalization due to knee disorders as categorized into specific International Classification of Diseases, tenth revision diagnoses (cruciate and collateral ligament tears, meniscal tears, traumatic chondral lesions, and patellar dislocations). Person-time injury-incidence rates were calculated by dividing the number of persons with a diagnosed knee injury by the total exposure time of 97,503 person-years. The number of subjects with surgical operations and military service class changes indicative of longer term notable disability are also reported. Risk factor analyses were performed by logistic regression. The person-based incidence of hospitalizations for knee injury was 11 cases per 1000 person-years [95% confidence interval (CI): 10.4-11.7]. The most important risk factors were higher age (odds ratio 1.7; 95% CI: 1.3-2.2) and obesity (odds ratio 1.6; 95% CI: 1.03-2.5). Two thirds of all subjects hospitalized for knee injuries had surgery, and one third had longer term notable disability. These findings indicate that knee injuries cause a significant burden of hospitalizations, often leading to surgery and longer term disability. © 2011 John Wiley & Sons A/S.

Learning curves for single incision and conventional laparoscopic right hemicolectomy: a multidimensional analysis

PubMed Central

Park, Yoonah; Yong, Yuen Geng; Jung, Kyung Uk; Huh, Jung Wook; Cho, Yong Beom; Kim, Hee Cheol; Lee, Woo Yong; Chun, Ho-Kyung

2015-01-01

Purpose This study aimed to compare the learning curves and early postoperative outcomes for conventional laparoscopic (CL) and single incision laparoscopic (SIL) right hemicolectomy (RHC). Methods This retrospective study included the initial 35 cases in each group. Learning curves were evaluated by the moving average of operative time, mean operative time of every five consecutive cases, and cumulative sum (CUSUM) analysis. The learning phase was considered overcome when the moving average of operative times reached a plateau, and when the mean operative time of every five consecutive cases reached a low point and subsequently did not vary by more than 30 minutes. Results Six patients with missing data in the CL RHC group were excluded from the analyses. According to the mean operative time of every five consecutive cases, learning phase of SIL and CL RHC was completed between 26 and 30 cases, and 16 and 20 cases, respectively. Moving average analysis revealed that approximately 31 (SIL) and 25 (CL) cases were needed to complete the learning phase, respectively. CUSUM analysis demonstrated that 10 (SIL) and two (CL) cases were required to reach a steady state of complication-free performance, respectively. Postoperative complications rate was higher in SIL than in CL group, but the difference was not statistically significant (17.1% vs. 3.4%). Conclusion The learning phase of SIL RHC is longer than that of CL RHC. Early oncological outcomes of both techniques were comparable. However, SIL RHC had a statistically insignificant higher complication rate than CL RHC during the learning phase. PMID:25960990

Development of longitudinally excited CO2 laser

NASA Astrophysics Data System (ADS)

Masroon, N. S.; Tanaka, M.; Tei, M.; Uno, K.; Tsuyama, M.; Nakano, H.

2018-05-01

Simple, compact, and affordable discharged-pumped CO2 laser controlled by a fast high voltage solid state switch has been developed. In this study, longitudinal excitation scheme has been adapted for simple configuration. In the longitudinal excitation scheme, the discharge is produced along the direction of the laser axis, and the electrodes are well separated with a small discharge cross-section. Triggered spark gap switch is usually used to switch out the high voltage because of simple and low cost. However, the triggered spark gap operates in the arc mode and suffer from recovery problem causing a short life time and low efficiency for high repetition rate operation. As a result, there is now considerable interest in replacing triggered spark gap switch with solid state switches. Solid state switches have significant advantages compared to triggered spark gap switch which include longer service lifetime, low cost and stable high trigger pulse. We have developed simple and low cost fast high voltage solid state switch that consists of series connected-MOSFETs. It has been installed to the longitudinally excited CO2 laser to realize the gap switch less operation. Characteristics of laser oscillation by varying the discharge length, charging voltage, capacitance and gas pressure have been evaluated. Longer discharge length produce high power of laser oscillation. Optimum charging voltage and gas pressure were existed for longitudinally excited CO2 laser.

Short-term outcomes using magnetic sphincter augmentation versus Nissen fundoplication for medically resistant gastroesophageal reflux disease.

PubMed

Louie, Brian E; Farivar, Alexander S; Shultz, Dale; Brennan, Christina; Vallières, Eric; Aye, Ralph W

2014-08-01

In 2012 the United States Food and Drug Administration approved implantation of a magnetic sphincter to augment the native reflux barrier based on single-series data. We sought to compare our initial experience with magnetic sphincter augmentation (MSA) with laparoscopic Nissen fundoplication (LNF). A retrospective case-control study was performed of consecutive patients undergoing either procedure who had chronic gastrointestinal esophageal disease (GERD) and a hiatal hernia of less than 3 cm. Sixty-six patients underwent operations (34 MSA and 32 LNF). The groups were similar in reflux characteristics and hernia size. Operative time was longer for LNF (118 vs 73 min) and resulted in 1 return to the operating room and 1 readmission. Preoperative symptoms were abolished in both groups. At 6 months or longer postoperatively, scores on the Gastroesophageal Reflux Disease Health Related Quality of Life scale improved from 20.6 to 5.0 for MSA vs 22.8 to 5.1 for LNF. Postoperative DeMeester scores (14.2 vs 5.1, p=0.0001) and the percentage of time pH was less than 4 (4.6 vs 1.1; p=0.0001) were normalized in both groups but statistically different. MSA resulted in improved gassy and bloated feelings (1.32 vs 2.36; p=0.59) and enabled belching in 67% compared with none of the LNFs. MSA results in similar objective control of GERD, symptom resolution, and improved quality of life compared with LNF. MSA seems to restore a more physiologic sphincter that allows physiologic reflux, facilitates belching, and creates less bloating and flatulence. This device has the potential to allow individualized treatment of patients with GERD and increase the surgical treatment of GERD. Copyright © 2014 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Global Regularity and Time Decay for the 2D Magnetohydrodynamic Equations with Fractional Dissipation and Partial Magnetic Diffusion

NASA Astrophysics Data System (ADS)

Dong, Bo-Qing; Jia, Yan; Li, Jingna; Wu, Jiahong

2018-05-01

This paper focuses on a system of the 2D magnetohydrodynamic (MHD) equations with the kinematic dissipation given by the fractional operator (-Δ )^α and the magnetic diffusion by partial Laplacian. We are able to show that this system with any α >0 always possesses a unique global smooth solution when the initial data is sufficiently smooth. In addition, we make a detailed study on the large-time behavior of these smooth solutions and obtain optimal large-time decay rates. Since the magnetic diffusion is only partial here, some classical tools such as the maximal regularity property for the 2D heat operator can no longer be applied. A key observation on the structure of the MHD equations allows us to get around the difficulties due to the lack of full Laplacian magnetic diffusion. The results presented here are the sharpest on the global regularity problem for the 2D MHD equations with only partial magnetic diffusion.

Laparosopic hand-assisted living donor nephrectomy: the Niguarda experience.

PubMed

Maione, G; Sansalone, C V; Aseni, P; De Roberto, A; Soldano, S; Mangoni, I; Perrino, L; Minetti, E; Civati, G

2005-01-01

Perioperative donor morbidity, a barrier to living organ donation, may be mitigated by the laparoscopic approach. From September 2002 to September 2004, 15 living donors, of ages ranging from 36 to 59 years, underwent laparoscopic nephrectomy. We used a hand-assisted device to increase the safety of the procedure. The average operating time was 200 minutes. The average blood loss was about 100 mL. The patients resumed oral intake and started walking within 1 day. The average postoperative hospital stay was 6 days. Although laparoscopic operating times were longer than those for traditional surgery, we showed benefits to the laparoscopic donor to be less postoperative pain, better cosmesis, shorter recovery time, and faster return to normal activities. We therefore consider laparoscopic nephrectomy a good alternative to traditional surgery for selected patients. Despite a lack of strong evidence, such as large prospective randomized studies, laparoscopic donor nephrectomy is likely to become the gold standard for donor nephrectomy in the near future.

Duration of surgical-orthodontic treatment.

PubMed

Häll, Birgitta; Jämsä, Tapio; Soukka, Tero; Peltomäki, Timo

2008-10-01

To study the duration of surgical-orthodontic treatment with special reference to patients' age and the type of tooth movements, i.e. extraction vs. non-extraction and intrusion before or extrusion after surgery to level the curve of Spee. The material consisted files of 37 consecutive surgical-orthodontic patients. The files were reviewed and gender, diagnosis, type of malocclusion, age at the initiation of treatment, duration of treatment, type of tooth movements (extraction vs. non-extraction and levelling of the curve of Spee before or after operation) and type of operation were retrieved. For statistical analyses two sample t-test, Kruskal-Wallis and Spearman rank correlation tests were used. Mean treatment duration of the sample was 26.8 months, of which pre-surgical orthodontics took on average 17.5 months. Patients with extractions as part of the treatment had statistically and clinically significantly longer treatment duration, on average 8 months, than those without extractions. No other studied variable seemed to have an impact on the treatment time. The present small sample size prevents reliable conclusions to be made. However, the findings suggest, and patients should be informed, that extractions included in the treatment plan increase chances of longer duration of surgical-orthodontic treatment.

Post-coma persons emerged from a minimally conscious state and showing multiple disabilities learn to manage a radio-listening activity.

PubMed

Lancioni, Giulio E; Singh, Nirbhay N; O'Reilly, Mark F; Sigafoos, Jeff; Colonna, Fabio; Buonocunto, Francesca; Sacco, Valentina; Megna, Marisa; Oliva, Doretta

2012-01-01

This study assessed microswitch-based technology to enable three post-coma adults, who had emerged from a minimally conscious state but presented motor and communication disabilities, to operate a radio device. The material involved a modified radio device, a microprocessor-based electronic control unit, a personal microswitch, and an amplified MP3 player. The study was carried out according to a non-concurrent multiple baseline design across participants. During the intervention, all three participants learned to operate the radio device, changing stations and tuning on some of them longer amounts of time than on others (i.e., suggesting preferences among the topics covered by those stations). They also ended a number of sessions before the maximum length of time allowed for them had elapsed. The practical (rehabilitation) implications of the findings were discussed. Copyright © 2011 Elsevier Ltd. All rights reserved.

Environment-friendly drilling operation technology

NASA Astrophysics Data System (ADS)

Luo, Huaidong; Jing, Ning; Zhang, Yanna; Huang, Hongjun; Wei, Jun

2017-01-01

Under the circumstance that international safety and environmental standards being more and more stringent, drilling engineering is facing unprecedented challenges, the extensive traditional process flow is no longer accepted, the new safe and environment-friendly process is more suitable to the healthy development of the industry. In 2015, CNPCIC adopted environment-friendly drilling technology for the first time in the Chad region, ensured the safety of well control, at the same time increased the environmental protection measure, reduced the risk of environmental pollution what obtain the ratification from local government. This technology carries out recovery and disposal of crude oil, cuttings and mud without falling on the ground. The final products are used in road and well site construction, which realizes the reutilization of drilling waste, reduces the operating cost, and provides a strong technical support for cost-cutting and performance-increase of drilling engineering under low oil price.

Making tomorrow's mistakes today: Evolutionary prototyping for risk reduction and shorter development time

NASA Astrophysics Data System (ADS)

Friedman, Gary; Schwuttke, Ursula M.; Burliegh, Scott; Chow, Sanguan; Parlier, Randy; Lee, Lorrine; Castro, Henry; Gersbach, Jim

1993-03-01

In the early days of JPL's solar system exploration, each spacecraft mission required its own dedicated data system with all software applications written in the mainframe's native assembly language. Although these early telemetry processing systems were a triumph of engineering in their day, since that time the computer industry has advanced to the point where it is now advantageous to replace these systems with more modern technology. The Space Flight Operations Center (SFOC) Prototype group was established in 1985 as a workstation and software laboratory. The charter of the lab was to determine if it was possible to construct a multimission telemetry processing system using commercial, off-the-shelf computers that communicated via networks. The staff of the lab mirrored that of a typical skunk works operation -- a small, multi-disciplinary team with a great deal of autonomy that could get complex tasks done quickly. In an effort to determine which approaches would be useful, the prototype group experimented with all types of operating systems, inter-process communication mechanisms, network protocols, packet size parameters. Out of that pioneering work came the confidence that a multi-mission telemetry processing system could be built using high-level languages running in a heterogeneous, networked workstation environment. Experience revealed that the operating systems on all nodes should be similar (i.e., all VMS or all PC-DOS or all UNIX), and that a unique Data Transport Subsystem tool needed to be built to address the incompatibilities of network standards, byte ordering, and socket buffering. The advantages of building a telemetry processing system based on emerging industry standards were numerous: by employing these standards, we would no longer be locked into a single vendor. When new technology came to market which offered ten times the performance at one eighth the cost, it would be possible to attach the new machine to the network, re-compile the application code, and run. In addition, we would no longer be plagued with lack of manufacturer support when we encountered obscure bugs. And maybe, hopefully, the eternal elusive goal of software portability across different vendors' platforms would finally be available. Some highlights of our prototyping efforts are described.

Making tomorrow's mistakes today: Evolutionary prototyping for risk reduction and shorter development time

NASA Technical Reports Server (NTRS)

Friedman, Gary; Schwuttke, Ursula M.; Burliegh, Scott; Chow, Sanguan; Parlier, Randy; Lee, Lorrine; Castro, Henry; Gersbach, Jim

1993-01-01

In the early days of JPL's solar system exploration, each spacecraft mission required its own dedicated data system with all software applications written in the mainframe's native assembly language. Although these early telemetry processing systems were a triumph of engineering in their day, since that time the computer industry has advanced to the point where it is now advantageous to replace these systems with more modern technology. The Space Flight Operations Center (SFOC) Prototype group was established in 1985 as a workstation and software laboratory. The charter of the lab was to determine if it was possible to construct a multimission telemetry processing system using commercial, off-the-shelf computers that communicated via networks. The staff of the lab mirrored that of a typical skunk works operation -- a small, multi-disciplinary team with a great deal of autonomy that could get complex tasks done quickly. In an effort to determine which approaches would be useful, the prototype group experimented with all types of operating systems, inter-process communication mechanisms, network protocols, packet size parameters. Out of that pioneering work came the confidence that a multi-mission telemetry processing system could be built using high-level languages running in a heterogeneous, networked workstation environment. Experience revealed that the operating systems on all nodes should be similar (i.e., all VMS or all PC-DOS or all UNIX), and that a unique Data Transport Subsystem tool needed to be built to address the incompatibilities of network standards, byte ordering, and socket buffering. The advantages of building a telemetry processing system based on emerging industry standards were numerous: by employing these standards, we would no longer be locked into a single vendor. When new technology came to market which offered ten times the performance at one eighth the cost, it would be possible to attach the new machine to the network, re-compile the application code, and run. In addition, we would no longer be plagued with lack of manufacturer support when we encountered obscure bugs. And maybe, hopefully, the eternal elusive goal of software portability across different vendors' platforms would finally be available. Some highlights of our prototyping efforts are described.

Complex task performance in Cyberspace. Surgical procedures in a telepresence environment.

PubMed

Bowersox, J C; LaPorta, A J; Cordts, P R; Bhoyrul, S; Shah, A

1996-01-01

To assess the capabilities of our fully functional, prototype telepresence surgery system, experienced surgeons performed complete operative procedures on live, anesthetized pigs. Cholecystectomy, the prototypical procedure for evaluating the integration of surgical skills, was successfully performed in six animals. There were no aborted attempts or complications. Other procedures completed included gastrotomy and enterotomy closures, anastomosis of the small intestine, and nephrectomy. No specific training was required for using the telepresence surgery system, and the "feel" of the system was described as intuitive. Operative times were longer than required in conventional, open surgery, most likely the result of the four degrees of freedom available in the manipulators of the current-generation system. Force feedback and high-resolution, stereoscopic video input facilitated performance. Surgeons operating through a first-generation telepresence system can achieve technical results equivalent to those obtained in conventional surgery.

High voltage threshold for stable operation in a dc electron gun

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

Yamamoto, Masahiro, E-mail: masahiro@post.kek.jp; Nishimori, Nobuyuki, E-mail: n-nishim@tagen.tohoku.ac.jp

We report clear observation of a high voltage (HV) threshold for stable operation in a dc electron gun. The HV hold-off time without any discharge is longer than many hours for operation below the threshold, while it is roughly 10 min above the threshold. The HV threshold corresponds to the minimum voltage where discharge ceases. The threshold increases with the number of discharges during HV conditioning of the gun. Above the threshold, the amount of gas desorption per discharge increases linearly with the voltage difference from the threshold. The present experimental observations can be explained by an avalanche discharge modelmore » based on the interplay between electron stimulated desorption (ESD) from the anode surface and subsequent secondary electron emission from the cathode by the impact of ionic components of the ESD molecules or atoms.« less

Continuous-wave organic dye lasers and methods

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

Shapira, Ofer; Chua, Song-Liang; Zhen, Bo

2014-09-16

An organic dye laser produces a continuous-wave (cw) output without any moving parts (e.g., without using flowing dye streams or spinning discs of solid-state dye media to prevent photobleaching) and with a pump beam that is stationary with respect to the organic dye medium. The laser's resonant cavity, organic dye medium, and pump beam are configured to excite a lasing transition over a time scale longer than the associated decay lifetimes in the organic dye medium without photobleaching the organic dye medium. Because the organic dye medium does not photobleach when operating in this manner, it may be pumped continuouslymore » so as to emit a cw output beam. In some examples, operation in this manner lowers the lasing threshold (e.g., to only a few Watts per square centimeter), thereby facilitating electrical pumping for cw operation.« less

A Single Center Study of 1,179 Heart Transplant Patients-Factors Affecting Pacemaker Implantation.

PubMed

Wellmann, Petra; Herrmann, Florian Ernst Martin; Hagl, Christian; Juchem, Gerd

2017-03-01

After around 10% of heart transplant patients require pacemaker implantation. The bradyarrhythmias causing pacemaker requirement include sinus node dysfunction (SND) and atrioventricular block (AVB). This study sought to define clinical predictors for pacemaker requirement as well as identify differences in the patient groups developing SND and AVB. Our operative database was used to collect retrospective recipient, donor, and operative data of all patients receiving orthotopic heart transplants between 1981 and 2016. In the 35-year period 1,179 transplants were performed (mean recipient age 45.5 ± 0.5 years, 20.4% female, 90.6% biatrial technique) with bradyarrhythmias requiring pacemaker implantation developing in 135 patients (11.5%). Independent risk factors were prolonged operative time 340 minutes versus 313 minutes (P = 0.027) and a biatrial anastomosis (P = 0.036). Ischemia time, cardiopulmonary bypass time, aortic cross clamp time, and reperfusion time all had no significant effect on pacemaker implantation rates. Similarly, whether the transplant was a reoperation, a retransplant, or performed after primary assist implantation had no effects on pacemaker implantation rates. There was no survival difference between the paced and nonpaced groups. The donor age was higher in the patients who developed AVB as the indication for pacemaker implantation (43 vs 34 years, P = 0.031). Patients with AVB had longer aortic cross clamp times and developed the arrhythmia later than those who developed SND. Use of the bicaval instead of the biatrial technique and shortened operative times should reduce pacemaker requirement after heart transplantation. Survival is not affected by this complication. © 2017 Wiley Periodicals, Inc.

Comparison between the Effects of Rocuronium, Vecuronium, and Cisatracurium Using Train-of-Four and Clinical Tests in Elderly Patients

PubMed Central

Sagir, Ozlem; Yucesoy Noyan, Funda; Koroglu, Ahmet; Cicek, Muslum; Ilksen Toprak, Huseyin

2013-01-01

Background Postoperative residual blockade, longer duration of action for neuromuscular blockade, and slower recovery were relatively common in elderly patients. Objectives We aimed to investigate the safety of train-of-four ratio and clinical tests in the assessment of patient recovery, and to determine the effects of the rocuronium, vecuronium, and cisatracurium on intubation, extubation and recovery times in elderly patients undergoing abdominal surgery. Patients and Methods After obtaining institutional approval and informed consent, 60 patients over 60 years old and undergoing elective abdominal operations were included in this double-blind, randomized clinical trial. Following a standard anesthesia induction, 0.6mg kg-1 rocuronium, 0.1mg kg-1 vecuronium, and 0.1mg kg-1 cisatracurium were administered to the patients in Group R, Group V, and Group C, respectively. Train-of-four (TOF) ratios were recorded at 10-minute intervals during and after the operation. Modified Aldrete Score (MAS) and clinical tests were recorded in the recovery room at 10-minute intervals. In addition, intubation and extubation times, duration of recovery room stay, and any complications were recorded. Results Intubation time was found to be shorter in Group R than that in Groups V and C (P ˂ 0.001). Times to positive visual disturbances and grip strength tests were shorter in Group C than that in Group V (P = 0.016 and P = 0.011, respectively). In Group R and group C, time to TOF ≥ 0.9 was significantly longer than all positive clinical test times except grip strength (P < 0.05). Conclusions We hold the opinion that cisatracurium is safer in elderly patients compared to other drugs. We also concluded that the usage of TOF ratio together with clinical tests is suitable for assessment of neuromuscular recovery in these patients. PMID:24223350

Dynamic-Type Ice Thermal Storage Systems

NASA Astrophysics Data System (ADS)

Ohira, Akiyoshi

This paper deals with reviews for research and development of a dynamic-type ice thermal storage system. This system has three main features. First, the ice thermal storage tank and the ice generator are separate. Second, ice is transported to the tank from the ice generator by water or air. Third, the ice making and melting processes are operated at the same time. Outlet water temperature from the dynamic-type ice thermal storage tank remains low for a longer time. In this paper, dynamic-Type ice thermal storage systems are divided into three parts: the ice making part, the ice transport part, and the cold energy release part. Each part is reviewed separately.

Brief communication: Post-seismic landslides, the tough lesson of a catastrophe

NASA Astrophysics Data System (ADS)

Fan, Xuanmei; Xu, Qiang; Scaringi, Gianvito

2018-01-01

The rock avalanche that destroyed the village of Xinmo in Sichuan, China, on 24 June 2017, brought the issue of landslide risk and disaster chain management in highly seismic regions back into the spotlight. The long-term post-seismic behaviour of mountain slopes is complex and hardly predictable. Nevertheless, the integrated use of field monitoring, remote sensing and real-time predictive modelling can help to set up effective early warning systems, provide timely alarms, optimize rescue operations, and perform secondary hazard assessments. We believe that a comprehensive discussion on post-seismic slope stability and on its implications for policy makers can no longer be postponed.

Travel time and concurrent-schedule choice: retrospective versus prospective control.

PubMed

Davison, M; Elliffe, D

2000-01-01

Six pigeons were trained on concurrent variable-interval schedules in which two different travel times between alternatives, 4.5 and 0.5 s, were randomly arranged. In Part 1, the next travel time was signaled while the subjects were responding on each alternative. Generalized matching analyses of performance in the presence of the two travel-time signals showed significantly higher response and time sensitivity when the longer travel time was signaled compared to when the shorter time was signaled. When the data were analyzed as a function of the previous travel time, there were no differences in sensitivity. Dwell times on the alternatives were consistently longer in the presence of the stimulus that signaled the longer travel time than they were in the presence of the stimulus that signaled the shorter travel time. These results are in accord with a recent quantitative account of the effects of travel time. In Part 2, no signals indicating the next travel time were given. When these data were analyzed as a function of the previous travel time, time-allocation sensitivity after the 4.5-s travel time was significantly greater than that after the 0.5-s travel time, but no such difference was found for response allocation. Dwell times were also longer when the previous travel time had been longer.

Constipation after thoraco-lumbar fusion surgery.

PubMed

Stienen, Martin N; Smoll, Nicolas R; Hildebrandt, Gerhard; Schaller, Karl; Tessitore, Enrico; Gautschi, Oliver P

2014-11-01

Thoraco-lumbar posterior fusion surgery is a frequent procedure used for patients with spinal instability due to tumor, trauma or degenerative disease. In the perioperative phase, many patients may experience vomiting, bowel irritation, constipation, or may even show symptoms of adynamic ileus possibly due to immobilization and high doses of opioid analgesics and narcotics administered during and after surgery. Retrospective single-center study on patients undergoing thoraco-lumbar fusion surgery for degenerative lumbar spine disease with instability in 2012. Study groups were built according to presence/absence of postoperative constipation, with postoperative constipation being defined as no bowel movement on postoperative days 0-2. Ninety-nine patients (39 males, 60 females) with a mean age of 57.1 ± 17.3 years were analyzed, of which 44 patients with similar age, gender, BMI and ASA-grades showed constipation (44.4%). Occurrence of constipation was associated with longer mean operation times (247 ± 62 vs. 214 ± 71 min; p=0.012), higher estimated blood loss (545 ± 316 vs. 375 ± 332 ml; p<0.001), and higher mean morphine dosages in the postoperative days 0-7 (the difference being significant on postoperative days 1 (48 mg vs. 30.9 mg, p=0.041) and 2 (43.2mg vs. 29.1mg, p=0.028). The equivalence dose of morphine administered during surgery was similar (339 ± 196 vs. 285 ± 144 mg; p=0.286). The use of laxatives in the postoperative days 0-7 was generally high in both study groups, while it was more frequent in patients experiencing constipation. One patient with constipation developed a sonographically confirmed paralytic ileus. Patients with constipation showed a tendency toward longer postoperative hospitalization (7.6 vs. 6.7 days, p=0.136). The rate of constipation was high after thoraco-lumbar fusion surgery. Moreover, it was associated with longer surgery time, higher blood loss, and higher postoperative morphine doses. Further trials are needed to prove if the introduction of faster and less invasive surgery techniques may have a positive side effect on bowel movement after spine surgery as they may reduce operation times, blood loss and postoperative morphine use. Copyright © 2014 Elsevier B.V. All rights reserved.

Therapeutic advances: Single incision laparoscopic hepatopancreatobiliary surgery

PubMed Central

Chang, Stephen Kin Yong; Lee, Kai Yin

2014-01-01

Single-port laparoscopic surgery (SPLS) is proposed to be a step towards minimizing the invasiveness of surgery, and has since gained popularity in several surgical sub-specialties including hepatopancreatobiliary surgery. SPLS has since been applied to cholecystectomy, liver resection as well as pancreatectomy for a multitude of pathologies. Benefits of SPLS over conventional multi-incision laparoscopic surgery include improved cosmesis and potentially post-operative pain at specific time periods and extra-umbilical sites. However, it is also associated with longer operating time, increased rate of complications, and increased rate of port-site hernia. There is no significant difference between length of hospital stay. SPLS has a significant learning curve that affects operating time, rate of conversion and rate of complications. In this article, we review the literature on SPLS in hepatobiliary surgery - cholecystectomy, hepatectomy and pancreatectomy, and offer tips on overcoming potential technical obstacles and minimizing the complications when performing SPLS - surgeon position, position of port and instruments, instrument crossing position, standard hand grip vs reverse hand grip, snooker cue guide position, prevention of incisional hernia. SPLS is a promising direction in laparoscopic surgery, and we recommend step-wise progression of applications of SPLS to various hepatopancreatobiliary surgeries to ensure safe adoption of the surgical technique. PMID:25339820

Preliminary design study of small long life boiling water reactor (BWR) with tight lattice thorium nitride fuel

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

Trianti, Nuri, E-mail: nuri.trianti@gmail.com, E-mail: szaki@fi.itba.c.id; Su'ud, Zaki, E-mail: nuri.trianti@gmail.com, E-mail: szaki@fi.itba.c.id; Arif, Idam, E-mail: nuri.trianti@gmail.com, E-mail: szaki@fi.itba.c.id

2014-09-30

Neutronic performance of small long-life boiling water reactors (BWR) with thorium nitride based fuel has been performed. A recent study conducted on BWR in tight lattice environments (with a lower moderator percentage) produces small power reactor which has some specifications, i.e. 10 years operation time, power density of 19.1 watt/cc and maximum excess reactivity of about 4%. This excess reactivity value is smaller than standard reactivity of conventional BWR. The use of hexagonal geometry on the fuel cell of BWR provides a substantial effect on the criticality of the reactor to obtain a longer operating time. Supported by a tightmore » concept lattice where the volume fraction of the fuel is greater than the moderator and fuel, Thorium Nitride give good results for fuel cell design on small long life BWR. The excess reactivity of the reactor can be reduced with the addition of gadolinium as burnable poisons. Therefore the hexagonal tight lattice fuel cell design of small long life BWR that has a criticality more than 20 years of operating time has been obtained.« less

Turnaround Time Modeling for Conceptual Rocket Engines

NASA Technical Reports Server (NTRS)

Nix, Michael; Staton, Eric J.

2004-01-01

Recent years have brought about a paradigm shift within NASA and the Space Launch Community regarding the performance of conceptual design. Reliability, maintainability, supportability, and operability are no longer effects of design; they have moved to the forefront and are affecting design. A primary focus of this shift has been a planned decrease in vehicle turnaround time. Potentials for instituting this decrease include attacking the issues of removing, refurbishing, and replacing the engines after each flight. less, it is important to understand the operational affects of an engine on turnaround time, ground support personnel and equipment. One tool for visualizing this relationship involves the creation of a Discrete Event Simulation (DES). A DES model can be used to run a series of trade studies to determine if the engine is meeting its requirements, and, if not, what can be altered to bring it into compliance. Using DES, it is possible to look at the ways in which labor requirements, parallel maintenance versus serial maintenance, and maintenance scheduling affect the overall turnaround time. A detailed DES model of the Space Shuttle Main Engines (SSME) has been developed. Trades may be performed using the SSME Processing Model to see where maintenance bottlenecks occur, what the benefits (if any) are of increasing the numbers of personnel, or the number and location of facilities, in addition to trades previously mentioned, all with the goal of optimizing the operational turnaround time and minimizing operational cost. The SSME Processing Model was developed in such a way that it can easily be used as a foundation for developing DES models of other operational or developmental reusable engines. Performing a DES on a developmental engine during the conceptual phase makes it easier to affect the design and make changes to bring about a decrease in turnaround time and costs.

Combined orbits and clocks from the IGS 2nd reprocessing

NASA Astrophysics Data System (ADS)

Griffiths, J.; Ray, J.

2016-12-01

In early 2015, the Analysis Centers (ACs) of the International GNSS Service (IGS) completed their second reanalysis of the full history of globally distributed GPS and GLONASS data collected since 1994. The suite of reprocessed AC solutions includes daily product files containing station positions, Earth rotation parameters, satellite orbits and clocks. This second reprocessing—or repro2—provided the IGS contribution to ITRF2014; it follows the successful first reprocessing, which provided the IGS input for ITRF2008. For this poster, we will discuss the newly combined repro2 GPS orbits and clocks. We also revisit our previous analysis of orbit day-boundary discontinuities with several significant changes and improvements: 1) Orbit discontinuities for the contributing ACs were studied in addition to those for the IGS repro2 combined orbits. (2) Apart from homogeneous reprocessing with updated analysis models, the main difference compared to the IGS Final operational products is that NOAA/NGS inputs were not submitted for the IGS reprocessing, yet they contribute heavily in the operational orbits in recent years. (3) Also, during spring 2016, the ESA modified their orbit model so that it is no longer consistent with the one used for reprocessing. A much longer span of orbits was available now, up to 11.2 years for some individual satellites, which allows a far better resolution of spectral features. 4) The procedure to compute orbit discontinuities has been further refined to account for extrapolation edge effects, improved geopotential fields, and to allow for spectral analysis of a longer time series of jumps. The satellite position time series used are complete enough that linear interpolation is necessary for only sparse gaps. So the key results are based on standard FFT power spectra (stacked over the available constellation and lightly smoothed). However, we have also computed Lomb-Scargle periodgrams to provide higher frequency resolution of some spectral peaks and to permit tests of the effect of excluding eclipse periods.

Effect of noise on the power spectrum of passively mode-locked lasers

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

Eliyahu, D.; Salvatore, R.A.; Yariv, A.

1997-01-01

We analyze the effects of noise on the power spectrum of pulse trains generated by a continuously operating passively mode-locked laser. The shape of the different harmonics of the power spectrum is calculated in the presence of correlated timing fluctuations between neighboring pulses and in the presence of amplitude fluctuations. The spectra at the different harmonics are influenced mainly by the nonstationary timing-jitter fluctuations; amplitude fluctuations slightly modify the spectral tails. Estimation of the coupling term between the longitudinal cavity modes or the effective saturable absorber coefficient is made from the timing-jitter correlation time. Experimental results from an external cavitymore » two-section semiconductor laser are given. The results show timing-jitter fluctuations having a relaxation time much longer than the repetition period. {copyright} 1997 Optical Society of America.« less

[A comparison of laparoscopic versus open repair for the surgical treatment of perforated peptic ulcers].

PubMed

Domínguez-Vega, Gerardo; Pera, Manuel; Ramón, José M; Puig, Sonia; Membrilla, Estela; Sancho, Joan; Grande, Luis

2013-01-01

To analyse the outcomes of laparoscopic versus open repair for perforated peptic ulcers (PPU). All patients undergoing PPU repair between January 2002 and March 2012 were included in the study. Demographic characteristics, operation time, complications, and length of hospital stay were evaluated. Two hundred and twelve patients (median age, 49 years) were included, 60 in the laparoscopic group and 52 in the open group. Patients operated laparoscopically were significantly younger and had a higher consumption of tobacco, alcohol and cannabis. Median acute symptoms time was shorter in the laparoscopic group (6h) compared to the open group (12h; P=.025) Symptoms time was shorter in the laparoscopic group. Median operating time was significantly longer in the laparoscopic group (104.5min vs. 76min, P=.025). The percentage of conversion to open repair was 25%. There was no difference in morbidity between 2 groups, but there were 3 deaths in the open group. Median hospital stay was significantly shorter in patients treated laparoscopically when compared with the open group (6 days vs. 8 days; P=.041). Laparoscopic and open repair are equally safe in the management of PPU. A shorter hospital stay can be achieved in the laparoscopic group. Copyright © 2012 AEC. Published by Elsevier Espana. All rights reserved.

Comparison of the treatment of herpes genitalis in men with proflavine photoinactivation, idoxuridine ointment, and normal saline.

PubMed Central

Taylor, P K; Doherty, N R

1975-01-01

36 male patients with genital infection by HSV confirmed by culture were each allocated to one of three treatment groups: (1) Proflavine photoinactivation, (2) 0.5 per cent. idoxuridine ointment (IDU), (3) Normal saline. They were assessed objectively at each attendance by measurement of the lesions with an operating microscope fitted with a measuring grid in one eyepiece. Material for culture for HSV was taken at each visit; the presence of symptoms (pain, discomfort, and irritation) was noted. The areas of lesions in the proflavine photoinactivation group remained larger significantly longer than in the other groups, the healing time was slower, and HSV could be isolated for longer. It is concluded that proflavine photoinactivation is of no greater value than 0.5 per cent. IDU or normal saline in the treatment of genital infection by HSV in the male. PMID:1093634

Cleft Lip and Palate Repair Using a Surgical Microscope.

PubMed

Kato, Motoi; Watanabe, Azusa; Watanabe, Shoji; Utsunomiya, Hiroki; Yokoyama, Takayuki; Ogishima, Shinya

2017-11-01

Cleft lip and palate repair requires a deep and small surgical field and is usually performed by surgeons wearing surgical loupes. Surgeons with loupes can obtain a wider surgical view, although headlights are required for the deepest procedures. Surgical microscopes offer comfort and a clear and magnification-adjustable surgical site that can be shared with the whole team, including observers, and easily recorded to further the education of junior surgeons. Magnification adjustments are convenient for precise procedures such as muscle dissection of the soft palate. We performed a comparative investigation of 18 cleft operations that utilized either surgical loupes or microscopy. Paper-based questionnaires were completed by staff nurses to evaluate what went well and what could be improved in each procedure. The operating time, complication rate, and scores of the questionnaire responses were statistically analyzed. The operating time when microscopy was used was not significantly longer than when surgical loupes were utilized. The surgical field was clearly shared with surgical assistants, nurses, anesthesiologists, and students via microscope-linked monitors. Passing surgical equipment was easier when sharing the surgical view, and preoperative microscope preparation did not interfere with the duties of the staff nurses. Surgical microscopy was demonstrated to be useful during cleft operations.

Medium Earth Orbit Scatterometer (MEOScat) Concept Phase Study

NASA Technical Reports Server (NTRS)

Spencer, Michael W.

2004-01-01

In this report, advanced scatterometer concept options to operate in the post-SeaWinds era are examined. In order to meet the future requirements of scientific and operational users, a variety of scatterometer systems capable of producing improved wind vector products are evaluated. Special emphasis is placed on addressing concept options that operate at higher altitudes in order to improve the temporal revisit time. A preliminary set of generalized wind measurement goals designed to meet the future needs of both scientific and operational communities is put forth. Geophysically based measurement constraints (such as allowable carrier frequencies and measurement incidence angles) are identified. It was found that a potential key constraint at higher satellite altitudes is the longer time required to make all of the azimuth measurements. The revisit and coverage characteristics of a variety of platform orbits throughout the MEO range is studied in detail, and a discussion of the associated increase in radiation is presented. The "trade space" of scatterometer architectures and design options, along with associated advantages and disadvantages, is described for mission options in the MEO range. Finally, key technology studies that will enable further development of a MEO scatterometer mission are identified.

Open versus laparoscopic unilateral inguinal hernia repairs: defining the ideal BMI to reduce complications.

PubMed

Willoughby, Ashley D; Lim, Robert B; Lustik, Michael B

2017-01-01

Open inguinal hernia repair is felt to be a less expensive operation than a laparoscopic one. Performing open repair on patients with an obese body mass index (BMI) results in longer operative times, longer hospital stay, and complications that will potentially impose higher cost to the facility and patient. This study aims to define the ideal BMI at which a laparoscopic inguinal hernia repair will be advantageous over open inguinal hernia repair. The NSQIP database was analyzed for (n = 64,501) complications, mortality, and operating time for open and laparoscopic inguinal hernia repairs during the time period from 2005 to 2012. Bilateral and recurrent hernias were excluded. Chi-square tests and Fisher's exact tests were used to assess associations between type of surgery and categorical variables including demographics, risk factors, and 30-day outcomes. Multivariable regression analyses were performed to determine whether odds ratios differed by level of BMI. The HCUP database was used for determining difference in cost and length of stay between open and laparoscopic procedures. There were 17,919 laparoscopic repairs and 46,582 open repairs in the study period. The overall morbidity (across all BMI categories) is statistically greater in the open repair group when compared to the laparoscopic group (p = 0.03). Postoperative complications (including wound disruption, failure to wean from the ventilator, and UTI) were greater in the open repair group across all BMI categories. Deep incisional surgical site infections (SSI) were more common in the overweight open repair group (p = 0.026). The return to the operating room across all BMI categories was statistically significant for the open repair group (n = 269) compared to the laparoscopic repair group (n = 70) with p = 0.003. There was no difference in the return to operating room between the BMI categories. The odds ratio (OR) was found to be statistically significant when comparing the obese category to both normal and overweight populations for the open procedure. Open hernia repairs have more complications than do laparoscopic ones; however, there does not appear to be a difference in treating obese patients with hernias using a laparoscopic approach versus an open one. One may consider using a laparoscopic approach in overweight patients (BMI 25-29.9) as there appears to be fewer deep SSI.

Short-Term Load Forecasting Based Automatic Distribution Network Reconfiguration: Preprint

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

Jiang, Huaiguang; Ding, Fei; Zhang, Yingchen

In the traditional dynamic network reconfiguration study, the optimal topology is determined at every scheduled time point by using the real load data measured at that time. The development of load forecasting technique can provide accurate prediction of load power that will happen in future time and provide more information about load changes. With the inclusion of load forecasting, the optimal topology can be determined based on the predicted load conditions during the longer time period instead of using the snapshot of load at the time when the reconfiguration happens, and thus it can provide information to the distribution systemmore » operator (DSO) to better operate the system reconfiguration to achieve optimal solutions. Thus, this paper proposes a short-term load forecasting based approach for automatically reconfiguring distribution systems in a dynamic and pre-event manner. Specifically, a short-term and high-resolution distribution system load forecasting approach is proposed with support vector regression (SVR) based forecaster and parallel parameters optimization. And the network reconfiguration problem is solved by using the forecasted load continuously to determine the optimal network topology with the minimum loss at the future time. The simulation results validate and evaluate the proposed approach.« less

Operational Efficiency of an Immunization Clinic Attached to Rural Health Training Centre in Delhi, India: A Time and Motion Study

PubMed Central

Kumar, Varun; Mangal, Abha; Panesar, Sanjeet; Yadav, Geeta; Talwar, Richa; Raut, Deepak; Singh, Saudan

2014-01-01

Background. Obtaining baseline data about current patterns of work is important for assessing the effects of interventions designed to improve care delivery. Time and motion studies allow for the most accurate measurement of structured components. Therefore, the present study was conducted to study the operational efficiency of an immunization clinic in Delhi, India. Methods. An observational cross-sectional study was conducted at the immunization clinic of Rural Health Training Centre in Delhi, India, from January 2014 to March 2014. The study composed two stage evaluations, a passive observation and a time and motion study. Systemic random sampling method was used to select 863 mothers/caregivers attending the immunization clinic. Results. At the immunization clinic, the study participants spent 64.1% of their total time in waiting. For new cases, the mean time taken for initial registration and receiving postvaccination advice was found to be significantly longer than old cases. Delivering health care services took more time during Mondays and also during the first hour of the day. Conclusion. Results of this study will guide public health decision-makers at all government levels in planning and implementation of immunization programs in developing countries. PMID:25431679

The impact on revenue of increasing patient volume at surgical suites with relatively high operating room utilization.

PubMed

Dexter, F; Macario, A; Lubarsky, D A

2001-05-01

We previously studied hospitals in the United States of America that are losing money despite limiting the hours that operating room (OR) staff are available to care for patients undergoing elective surgery. These hospitals routinely keep utilization relatively high to maximize revenue. We tested, using discrete-event computer simulation, whether increasing patient volume while being reimbursed less for each additional patient can reliably achieve an increase in revenue when initial adjusted OR utilization is 90%. We found that increasing the volume of referred patients by the amount expected to fill the surgical suite (100%/90%) would increase utilization by <1% for a hospital surgical suite (with longer duration cases) and 4% for an ambulatory surgery suite (with short cases). The increase in patient volume would result in longer patient waiting times for surgery and more patients leaving the surgical queue. With a 15% reduction in payment for the new patients, the increase in volume may not increase revenue and can even decrease the contribution margin for the hospital surgical suite. The implication is that for hospitals with a relatively high OR utilization, signing discounted contracts to increase patient volume by the amount expected to "fill" the OR can have the net effect of decreasing the contribution margin (i.e., profitability). Hospitals may try to attract new surgical volume by offering discounted rates. For hospitals with a relatively high operating room utilization (e.g., 90%), computer simulations predict that increasing patient volume by the amount expected to "fill" the operating room can have the net effect of decreasing contribution margin (i.e., profitability).

Impact of stone branch number on outcomes of percutaneous nephrolithotomy for treatment of staghorn calculi.

PubMed

Qi, Shiyong; Li, Li; Liu, Ranlu; Qiao, Baomin; Zhang, Zhihong; Xu, Yong

2014-02-01

To determine the impact of staghorn calculi branch number on outcomes of percutaneous nephrolithotomy (PNL). Retrospectively, we evaluated 371 patients (386 renal units) who underwent PNL for staghorn calculi. All calculi were showed with CT three-dimensional reconstruction (3DR) imaging preoperatively. From 3DR images, the number of stone branching into minor renal calices was recorded. According to the number, patients were divided into four groups. Group 1: the branch number 2-4; Group 2: the branch number 5-7; Group 3: the branch number 8-10; Group 4: the branch number >10. The number of percutaneous tract, operative time, staged PNL, intraoperative blood loss, postoperative hospital stay, complications, main stone composition, and stone clearance rate were compared. A significantly higher ratio of multitract (p<0.001) and staged PNL (p<0.001), a longer operative time (p<0.001) and postoperative hospital stay (p=0.043), and a lower rate of stone clearance (p<0.05) were found in PNL for calculi with a stone branch number ≥5. There was no statistical difference in intraoperative blood loss (p=0.101) and main stone composition (p=0.546). There was no statistically meaningful difference among the four groups based on the Clavien complication system (p=0.46). With the stone branch number more than five, the possibility of multitract and staged PNL, lower rate of stone clearance, and a longer postoperative hospital stay increases for staghorn calculi.

Sampling for Patient Exit Interviews: Assessment of Methods Using Mathematical Derivation and Computer Simulations.

PubMed

Geldsetzer, Pascal; Fink, Günther; Vaikath, Maria; Bärnighausen, Till

2018-02-01

(1) To evaluate the operational efficiency of various sampling methods for patient exit interviews; (2) to discuss under what circumstances each method yields an unbiased sample; and (3) to propose a new, operationally efficient, and unbiased sampling method. Literature review, mathematical derivation, and Monte Carlo simulations. Our simulations show that in patient exit interviews it is most operationally efficient if the interviewer, after completing an interview, selects the next patient exiting the clinical consultation. We demonstrate mathematically that this method yields a biased sample: patients who spend a longer time with the clinician are overrepresented. This bias can be removed by selecting the next patient who enters, rather than exits, the consultation room. We show that this sampling method is operationally more efficient than alternative methods (systematic and simple random sampling) in most primary health care settings. Under the assumption that the order in which patients enter the consultation room is unrelated to the length of time spent with the clinician and the interviewer, selecting the next patient entering the consultation room tends to be the operationally most efficient unbiased sampling method for patient exit interviews. © 2016 The Authors. Health Services Research published by Wiley Periodicals, Inc. on behalf of Health Research and Educational Trust.

[Efficacy analysis of proximally extended resection for locally advanced rectal cancer after neoadjuvant chemoradiotherapy].

PubMed

Qin, Qiyuan; Kuang, Yingyi; Ma, Tenghui; Wu, Yali; Wang, Huaiming; Pi, Yanna; Wang, Hui; Wang, Lei

2017-11-25

To evaluate the short-term outcomes and perioperative safety of proximally extended resection for locally advanced rectal cancer after neoadjuvant chemoradiotherapy. From colorectal cancer database in The Sixth Affiliated Hospital of Sun Yat-sen University, a cohort of patients who underwent neoadjuvant chemoradiotherapy(1.8-2.0 Gy per day, 25-28 fractions, concurrent fluorouracil-based chemotherapy) followed by curative sphincter-preserving surgery for locally advanced rectal cancer between May 2016 and June 2017 were retrospectively identified. Exclusion criteria were synchronous colon cancer, intraoperatively confirmed distal metastasis, multiple visceral resection, and emergency operation. Thirty-one patients underwent proximal extended resection and two were excluded for incomplete extended resection, then 29 patients were enrolled as the extended group. Using propensity scores matching with 1/1 ration, 29 locally advanced rectal cancer patients who underwent conventional resection after neoadjuvant chemoradiotherapy at the same time were matched as the conventional group. Clinical data of two groups were analyzed, and the baseline characteristics and short-term outcomes were compared using the t test, χ 2 test, or Mann-Whitney U test. Two groups were well balanced with respect to the baseline characteristics after propensity score matching. As compared with conventional group, patients in extended group had longer surgical specimen [(18.8±5.1) cm vs.(11.6±3.4) cm, t=6.314, P=0.000] and longer proximal resection margin [(14.8±5.5) cm vs.(8.2±3.0) cm, t=5.725, P=0.000], but also had longer total operating time [(322.4±100.7) min vs.(254.6±70.3) min, t=2.975, P=0.004] and more intraoperative blood loss [100(225) ml vs. 100(50) ml, Z=-2.403, P=0.016]. No significant differences were observed in the length of distal resection margin, ratio of positive resection margin, number of retrieved lymph node, time of analgesic use, time of draining tube use, time to first flatus, time to first oral diet, and postoperative hospital stay. During the perioperative period of 30 days, the morbidity of complication in extended group and conventional group was 17.2%(5/29) and 34.5% (10/29), respectively (P=0.134). Proximally extended resection is a radical and safe surgical alternative for locally advanced rectal cancer after neoadjuvant chemoradiotherapy, which can potentially reduce the risk of anastomosis complication.

U28 : longer combination vehicle's impact on improving operational efficiency, freight flows and traffic congestion.

DOT National Transportation Integrated Search

2011-12-01

Longer Combination Vehicles (LCVs) are able to carry more freight than conventional single trailer trucks. As a result, these trucks can increase efficiencies and benefits for freight movements as less fuel and less labor is used per ton of cargo. Ho...

[Evaluation of intraventricular dyssynchrony by quantitative tissue velocity imaging in rats of post-infarction heart failure].

PubMed

Wang, Yan; Zhu, Wenhui; Duan, Xingxing; Zhao, Yongfeng; Liu, Wengang; Li, Ruizhen

2011-04-01

To evaluate intraventricular systolic dyssynchrony in rats with post-infarction heart failure by quantitative tissue velocity imaging combining synchronous electrocardiograph. A total of 60 male SD rats were randomly assigned to 3 groups: a 4 week post-operative group and an 8 week post-operation group (each n=25, with anterior descending branch of the left coronary artery ligated), and a sham operation group (n=10, with thoracotomy and open pericardium, but no ligation of the artery). The time to peak systolic velocity of regional myocardial in the rats was measured and the index of the left intraventricular dyssynchrony was calculated. All indexes of the heart function became lower as the heart failure worsened except the left ventricle index in the post-operative groups. All indexes of the dyssynchrony got longer in the post-operative groups (P<0.05), while the changes in the sham operation group were not significantly different (P>0.05). Quantitative tissue velocity imaging combining synchronous electrocardiograph can analyse the intraventricular systolic dyssynchrony accurately.

The Association of Daytime Maternal Napping and Exercise With Nighttime Sleep in First-Time Mothers Between 3 and 6 Months Postpartum.

PubMed

Lillis, Teresa A; Hamilton, Nancy A; Pressman, Sarah D; Khou, Christina S

2016-10-19

This study investigated the relationship of daytime maternal napping, exercise, caffeine, and alcohol intake to objective and subjective sleep indices. Sixty healthy, nondepressed, first-time mothers between 3 and 6 months postpartum. Seven consecutive days of online behavior diaries, sleep diaries, and wrist actigraphy, collecting Total Sleep Time (TST), Sleep Onset Latency (SOL), and Wake After Sleep Onset (WASO). After controlling for infant age, employment status, infant feeding method, and infant sleeping location, mixed linear models showed that longer average exercise durations were associated with longer average TST, and longer average nap durations were associated with longer average WASO durations. Significant within-person differences in TST and SOL were also observed, such that, on days when participants exercised and napped longer than average, their respective TST and SOL durations that night were longer. Shorter nap durations and longer exercise durations were associated with longer TST, shorter SOL, and reduced WASO. Even small changes in daily exercise and napping behaviors could lead to reliable improvements in postpartum maternal sleep.

Endometrial cancer surgery costs: robot vs laparoscopy.

PubMed

Holtz, David O; Miroshnichenko, Gennady; Finnegan, Mark O; Chernick, Michael; Dunton, Charles J

2010-01-01

To compare surgical costs for endometrial cancer staging between robotic-assisted and traditional laparoscopic methods. Retrospective chart review from November 2005 to July 2006 (Canadian Task Force classification II-3). Non-university-affiliated teaching hospital. Thirty-three women with diagnosed endometrial cancer undergoing hysterectomy, bilateral salpingo-oophorectomy, and pelvic and paraaortic lymph node resection. Patients underwent either robotic or traditional laparoscopic surgery without randomization. Hospital cost data were obtained for operating room time, instrument use, and disposable items from hospital billing records and provided by the finance department. Separate overall hospital stay costs were also obtained. Mean operative costs were higher for robotic procedures ($3323 vs $2029; p<.001), due in part to longer operating room time ($1549 vs $1335; p=.03). The more significant cost difference was due to disposable instrumentation ($1755 vs $672; p<.001). Total hospital costs were also higher for robotic-assisted procedures ($5084 vs $ 3615; p=.002). Robotic surgery costs were significantly higher than traditional laparoscopy costs for staging of endometrial cancer in this small cohort of patients. Copyright (c) 2010 AAGL. Published by Elsevier Inc. All rights reserved.

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

Lee, Young-Ho; Byun, Thak Sang

Accident-tolerant fuels are expected to have considerably longer coping time to respond to the loss of active cooling under severe accidents and, at the same time, have comparable or improved fuel performance during normal operation. The wear resistance of accident tolerant fuels, therefore, needs to be examined to determine the applicability of these cladding candidates to the current operating PWRs because the most common failure of nuclear fuel claddings is still caused by grid-to-rod fretting during normal operations. In this study, reciprocating sliding wear tests on three kinds of cladding candidates for accident-tolerant fuels have been performed to investigate themore » tribological compatibilities of selfmated cladding candidates and to determine the direct applicability of conventional Zirconium-based alloys as supporting structural materials. The friction coefficients of the cladding candidates are strongly influenced by the test environments and coupled materials. The wear test results under water lubrication conditions indicate that the supporting structural materials for the cladding candidates of accident-tolerant fuels need to be replaced with the same cladding materials instead of using conventional Zirconium-based alloys.« less

Development and operation of a high-throughput accurate-wavelength lens-based spectrometer a)

DOE PAGES

Bell, Ronald E.

2014-07-11

A high-throughput spectrometer for the 400-820 nm wavelength range has been developed for charge exchange recombination spectroscopy or general spectroscopy. A large 2160 mm -1 grating is matched with fast f /1.8 200 mm lenses, which provide stigmatic imaging. A precision optical encoder measures the grating angle with an accuracy ≤ 0.075 arc seconds. A high quantum efficiency low-etaloning CCD detector allows operation at longer wavelengths. A patch panel allows input fibers to interface with interchangeable fiber holders that attach to a kinematic mount behind the entrance slit. The computer-controlled hardware allows automated control of wavelength, timing, f-number, automated datamore » collection, and wavelength calibration.« less

Space tug thermal control

NASA Technical Reports Server (NTRS)

Ward, T. L.

1975-01-01

The future development of full capability Space Tug will impose strict requirements upon the thermal design. While requiring a reliable and reusable design, Space Tug must be capable of steady-state and transient thermal operation during any given mission for mission durations of up to seven days and potentially longer periods of time. Maximum flexibility and adaptability of Space Tug to the mission model requires that the vehicle operate within attitude constraints throughout any specific mission. These requirements were translated into a preliminary design study for a geostationary deploy and retrieve mission definition for Space Tug to determine the thermal control design requirements. Results of the study are discussed with emphasis given to some of the unique avenues pursued during the study, as well as the recommended thermal design configuration.

Risk factors for postoperative retropharyngeal hematoma after anterior cervical spine surgery.

PubMed

O'Neill, Kevin R; Neuman, Brian; Peters, Colleen; Riew, K Daniel

2014-02-15

Retrospective review of prospective database. To investigate risk factors involved in the development of anterior cervical hematomas and determine any impact on patient outcomes. Postoperative (PO) hematomas after anterior cervical spine surgery require urgent recognition and treatment to avoid catastrophic patient morbidity or death. Current studies of PO hematomas are limited. Cervical spine surgical procedures performed on adults by the senior author at a single academic institution from 1995 to 2012 were evaluated. Demographic data, surgical history, operative data, complications, and neck disability index (NDI) scores were recorded prospectively. Cases complicated by PO hematoma were reviewed, and time until hematoma development and surgical evacuation were determined. Patients who developed a hematoma (HT group) were compared with those that did not (no-HT group) to identify risk factors. NDI outcomes were compared at early (<11 mo) and late (>11 mo) time points. There were 2375 anterior cervical spine surgical procedures performed with 17 occurrences (0.7%) of PO hematoma. In 11 patients (65%) the hematoma occurred within 24 hours PO, whereas 6 patients (35%) presented at an average of 6 days postoperatively. All underwent hematoma evacuation, with 2 patients (12%) requiring emergent cricothyroidotomy. Risk factors for hematoma were found to be (1) the presence of diffuse idiopathic skeletal hyperostosis (relative risk = 13.2, 95% confidence interval = 3.2-54.4), (2) presence of ossification of the posterior longitudinal ligament (relative risk = 6.8, 95% confidence interval = 2.3-20.6), (3) therapeutic heparin use (relative risk 148.8, 95% confidence interval = 91.3-242.5), (4) longer operative time, and (5) greater number of surgical levels. The occurrence of a PO hematoma was not found to have a significant impact on either early (HT: 30, no-HT: 28; P = 0.86) or late average NDI scores (HT: 28, no-HT 31; P = 0.76). With fast recognition and treatment, no long-term detriment from PO anterior cervical hematoma was found. We identified risk factors to be (1) presence of diffuse idiopathic skeletal hyperostosis, (2) presence of ossification of the posterior longitudinal ligament, (3) therapeutic heparin use, (4) longer operative time, and (5) greater number of surgical levels. 4.

78 FR 72023 - Drawbridge Operation Regulation; Genessee River, Rochester, NY

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-02

... Bridge that once required draw operations in 33 CFR 117.785 was removed from the waterway in 2013... effective date. This rule removes the CSX Transportation Bridge draw operation requirements under 33 CFR 117... the regulatory burden related to the draw operations for this bridge that is no longer in existence...

Incidence and management of anastomotic leakage following laparoscopic prostatectomy with implementation of a new anastomotic technique incorporating posterior bladder neck tailoring.

PubMed

Sukkarieh, T; Harmon, J; Penna, F; Parra, R

2007-01-01

In laparoscopic prostatectomies, vesicourethral anastomotic leaks may result in significant morbidity because of the chemical and metabolic derangements created by urine within the peritoneal cavity. To date, minimal data are available on this problem. Herein we present our experience with urine leaks after RALP. Over a period of 24 months, 135 men underwent RALP. Any drainage creatinine greater than two times the serum creatinine was considered as an anastomotic leak. According to our criteria, 20% of the first 110 patients developed an anastomotic leak. The patients were analyzed in two groups, those with and without leaks. In the two groups, there was no statistically significant difference in age, height, weight, prostate volume and pre-op hemoglobin. The patients with leaks did have higher rate of prior abdominal surgery (50 vs. 36%), higher average pre-operative PSA values (7.6 vs. 6.1), higher rates of multiple biopsies (27 vs. 17%) and a higher average BMI (29.6 vs. 27.8). Intraoperative differences included an average of 30 min longer operative time and 66 cm(3) higher average EBL in patients with leaks. The transfusion rate was higher in the leak group at 18 vs. 1% in the no leak group. Recovery tended to be longer in patients with leaks, with hospital stays of an average of 3.6 days longer. The most common indication for prolonged hospitalization was ileus, which 55% of patients with leaks developed. Management included placing the catheter on mild traction, continuous antibiotics and taking the drain-off suction with caution to monitor the signs of a worsening ileus. In the last 25 patients, we revised our anastomotic technique. We now include posterior tailoring of the bladder neck prior to the vesicourethral anastomosis when the bladder neck is enlarged. This facilitates a water-tight anastomosis. Using this technique, we have yet to see the anastomotic leak. In RALPs, anastomotic leaks can lead to ileus formation and longer hospital stays. These leaks are associated with a higher average blood loss and transfusion rate. Management should focus on prevention. Since we have incorporated posterior bladder neck tailoring with the anastomosis, the problem has been markedly reduced.

Long-term results after the Rastelli repair for transposition of the great arteries.

PubMed

Hörer, Jürgen; Schreiber, Christian; Dworak, Eva; Cleuziou, Julie; Prodan, Zsolt; Vogt, Manfred; Holper, Klaus; Lange, Rüdiger

2007-06-01

This study sought to assess risk factors for late mortality after the Rastelli operation for patients with transposition of the great arteries, ventricular septal defect, and left ventricular outflow tract obstruction. Records of 39 patients who underwent the Rastelli operation between 1977 and 2004 were reviewed. Median age at the time of operation was 5.1 years (2.2 years within the last 5 years). There were no early deaths. During a median follow-up of 8.9 years (range, 0 to 25 years), 2 patients died of sudden death, 1 of pneumonia, 1 during reoperation, and 2 received heart transplantation. Freedom from death or transplantation was 93.8% +/- 4.3% and 57.5% +/- 15.1% at 10 and 20 years, respectively. Freedom from conduit replacement was 48.8% +/- 10.3% and 32.5% +/- 10.3% at 10 and 20 years, respectively. Subvalvular and valvular left ventricular outflow tract obstruction (p = 0.012), stenosis of the peripheral pulmonary arteries (p < 0.001), enlargement of the ventricular septal defect (p = 0.030), and longer ischemic time (p = 0.015) were predictive for death or transplantation. Patients younger than 4 years at the time of the Rastelli operation showed a trend toward a better freedom from death or transplantation (p = 0.068), but needed significantly more conduit replacements (p = 0.038) compared with patients 4 years or older. The Rastelli operation is a low-risk procedure with regard to early mortality. The status of the pulmonary arteries and ventricular septal defect enlargement are predictive for long-term survival. Patients 4 years of age or older at the time of the Rastelli operation require fewer reoperations for conduit exchange. Nevertheless, early Rastelli repair is recommended because patients 4 years or older are at risk for a higher long-term mortality.

Project CHECO Southeast Asia Report. BUFFALO HUNTER 1970 - 1972

DTIC Science & Technology

1973-07-24

era, however, the drone’s use was no longer a secret. This report examines the entire BUFFALO HUNTER operation -- management , targeting, drone capabilities, mission planning and execution, and operational results.

Robotized production systems observed in modern plants

NASA Astrophysics Data System (ADS)

Saverina, A. N.

1985-09-01

Robots, robotized lines and sectors are no longer innovations in shops at automotive plants. The widespread robotization of automobile assembly operations is described in general terms. Robot use for machining operation is also discussed.

40 CFR 258.61 - Post-closure care requirements.

Code of Federal Regulations, 2011 CFR

2011-07-01

... the final cover; (2) Maintaining and operating the leachate collection system in accordance with the... stop managing leachate if the owner or operator demonstrates that leachate no longer poses a threat to...

40 CFR 258.61 - Post-closure care requirements.

Code of Federal Regulations, 2014 CFR

2014-07-01

... the final cover; (2) Maintaining and operating the leachate collection system in accordance with the... stop managing leachate if the owner or operator demonstrates that leachate no longer poses a threat to...

40 CFR 258.61 - Post-closure care requirements.

Code of Federal Regulations, 2012 CFR

2012-07-01

... the final cover; (2) Maintaining and operating the leachate collection system in accordance with the... stop managing leachate if the owner or operator demonstrates that leachate no longer poses a threat to...

40 CFR 258.61 - Post-closure care requirements.

Code of Federal Regulations, 2013 CFR

2013-07-01

... the final cover; (2) Maintaining and operating the leachate collection system in accordance with the... stop managing leachate if the owner or operator demonstrates that leachate no longer poses a threat to...

Robotic bariatric surgery: a systematic review.

PubMed

Fourman, Matthew M; Saber, Alan A

2012-01-01

Obesity is a nationwide epidemic, and the only evidence-based, durable treatment of this disease is bariatric surgery. This field has evolved drastically during the past decade. One of the latest advances has been the increased use of robotics within this field. The goal of our study was to perform a systematic review of the recent data to determine the safety and efficacy of robotic bariatric surgery. The setting was the University Hospitals Case Medical Center (Cleveland, OH). A PubMed search was performed for robotic bariatric surgery from 2005 to 2011. The inclusion criteria were English language, original research, human, and bariatric surgical procedures. Perioperative data were then collected from each study and recorded. A total of 18 studies were included in our review. The results of our systematic review showed that bariatric surgery, when performed with the use of robotics, had similar or lower complication rates compared with traditional laparoscopy. Two studies showed shorter operative times using the robot for Roux-en-Y gastric bypass, but 4 studies showed longer operative times in the robotic arm. In addition, the learning curve appears to be shorter when robotic gastric bypass is compared with the traditional laparoscopic approach. Most investigators agreed that robotic laparoscopic surgery provides superior imaging and freedom of movement compared with traditional laparoscopy. The application of robotics appears to be a safe option within the realm of bariatric surgery. Prospective randomized trials comparing robotic and laparoscopic outcomes are needed to further define the role of robotics within the field of bariatric surgery. Longer follow-up times would also help elucidate any long-term outcomes differences with the use of robotics versus traditional laparoscopy. Copyright © 2012 American Society for Metabolic and Bariatric Surgery. All rights reserved.

The outcomes of the elderly in acute care general surgery.

PubMed

St-Louis, E; Sudarshan, M; Al-Habboubi, M; El-Husseini Hassan, M; Deckelbaum, D L; Razek, T S; Feldman, L S; Khwaja, K

2016-02-01

Elderly patients form a growing subset of the acute care surgery (ACS) population. Older age may be associated with poorer outcomes for some elective procedures, but there are few studies focusing on outcomes for the elderly ACS population. Our objective is to characterize differences in mortality and morbidity for acute care surgery patients >80 years old. A retrospective review of all ACS admissions at a large teaching hospital over 1 year was conducted. Patients were classified into non-elderly (<80 years old) and elderly (≥80 years old). In addition to demographic differences, outcomes including care efficiency, mortality, postoperative complications, and length of stay were studied. Data analysis was completed with the Student's t test for continuous variables and Fisher's exact test for categorical variables using STATA 12 (College Station, TX, USA). We identified 467 non-elderly and 60 elderly patients with a mean age-adjusted Charlson score of 3.2 and 7.2, respectively (p < 0.001) and a mortality risk of 1.9 and 11.7 %, respectively (p < 0.001). The elderly were at risk of longer duration (>4 days) hospital stay (p = 0.05), increased postoperative complications (p = 0.002), admission to the ICU (p = 0.002), and were more likely to receive a non-operative procedure (p = 0.003). No difference was found (p = NS) for patient flow factors such as time to consult general surgery, time to see consult by general surgery, and time to operative management and disposition. Compared to younger patients admitted to an acute care surgery service, patients over 80 years old have a higher risk of complications, are more likely to require ICU admission, and stay longer in the hospital.

Early results of a prospective study on the pyrolytic carbon (pyrocarbon) Amandys® for osteoarthritis of the wrist

PubMed Central

Daruwalla, ZJ; Davies, KL; Shafighian, A; Gillham, NR

2012-01-01

INTRODUCTION The preliminary results of a pyrocarbon interpositional radiocarpal implant in a small cohort of patients were reviewed. As it is currently only a limited release product, we describe to potential users early complications and negative outcomes. METHODS Patients were assessed using pain levels, ranges of motion, grip strength, type of and time to return to work as well as pre-operative and post-operative DASH (Disabilities of the Arm, Shoulder and Hand) scores. Radiographs were taken and patient satisfaction was recorded. RESULTS All six patients were contacted. One was not satisfied. Three had reduced motion. None experienced squeaking. There were no immediate or late post-operative complications. There was one early volar displacement of an implant. CONCLUSIONS Although our early results are somewhat encouraging, further and longer studies are warranted before supporting the use of this particular pyrocarbon implant as a primary procedure. PMID:23031769

[Comparative study on graft of autogeneic iliac bone and tissue engineered bone].

PubMed

Shen, Bing; Xie, Fu-lin; Xie, Qing-fang

2002-11-01

To compare the clinical results of repairing bone defect of limbs with tissue engineering technique and with autogeneic iliac bone graft. From July 1999 to September 2001, 52 cases of bone fracture were randomly divided into two groups (group A and B). Open reduction and internal fixation were performed in all cases as routine operation technique. Autogeneic iliac bone was implanted in group A, while tissue engineered bone was implanted in group B. Routine postoperative treatment in orthopedic surgery was taken. The operation time, bleeding volume, wound healing and drainage volume were compared. The bone union was observed by the X-ray 1, 2, 3, and 5 months after operation. The sex, age and disease type had no obvious difference between groups A and B. all the wounds healed with first intention. The swelling degree of wound and drainage volume had no obvious difference. The operation time in group A was longer than that in group B (25 minutes on average) and bleeding volume in group A was larger than that in group B (150 ml on average). Bone union completed within 3 to 7 months in both groups. But there were 2 cases of delayed union in group A and 1 case in group B. Repair of bone defect with tissue engineered bone has as good clinical results as that with autogeneic iliac bone graft. In aspect of operation time and bleeding volume, tissue engineered bone graft is superior to autogeneic iliac bone.

Lengthening Temporalis Myoplasty for Single-Stage Smile Reconstruction in Children with Facial Paralysis.

PubMed

Panossian, Andre

2016-04-01

Free muscle transfer for dynamic smile reanimation in facial paralysis is not always predictable with regard to cosmesis. Hospital stays range from 5 to 7 days. Prolonged operative times, longer hospital stays, and excessive cheek bulk are associated with free flap options. Lengthening temporalis myoplasty offers single-stage smile reanimation with theoretical advantages over free tissue transfer. From 2012 to 2014, 18 lengthening temporalis myoplasties were performed in 14 children for smile reconstruction. A retrospective chart review was completed for demographics, operative times, length of hospital stay, and perioperative complications. Fourteen consecutive patients with complete facial paralysis were included. Four patients underwent single-stage bilateral reconstruction, and 10 underwent unilateral procedures. Diagnoses included Möbius syndrome (n = 5), posterior cranial fossa tumors (n = 4), posttraumatic (n = 2), hemifacial microsomia (n = 1), and idiopathic (n = 2). Average patient age was 10.1 years. Average operative time was 410 minutes (499 minutes for bilateral lengthening temporalis myoplasty and 373 for unilateral lengthening temporalis myoplasty). Average length of stay was 3.3 days (4.75 days for bilateral lengthening temporalis myoplasty and 2.8 for unilateral lengthening temporalis myoplasty). Nine patients required minor revisions. Lengthening temporalis myoplasty is a safe alternative to free tissue transfer for dynamic smile reconstruction in children with facial paralysis. Limited donor-site morbidity, shorter operative times, and shorter hospital stays are some benefits over free flap options. However, revisions are required frequently secondary to tendon avulsions and adhesions. Therapeutic, IV.

Bupivacaine Versus Liposomal Bupivacaine For Pain Control.

PubMed

Beiranvand, Siavash; Moradkhani, Mahmoud Reza

2017-11-06

Local infiltrations and regional blocks have been some of the effective ways employed to manage and control post-operative pain. One of the limitations of administration of local anesthesia drugs in post-operative conditions is its inability to act for a longer period of time. Multi-vesicular liposomes made up of bupivacaine have been progressively used for their increased duration of action. Compared to bupivacaine HCL, local infiltration of liposomal bupivacaine have shown to have a significantly increase the duration and delay in peak plasma concentration. In this article, we attempt to compare liposomal bupivacaine and bupivacaine based on available clinical literatures. Liposomal bupivacaine has been demonstrated to have promising implications in post- operative pain control resulting in increased patient satisfaction; reduced hospital admission and opioid induced adverse events. Clinical studies have identified liposomal bupivacaine to be effective in delivering increased post-operative pain control. The purpose of this review is to give a comprehensive comparison between bupivacaine liposomal and conventional bupivacaine based on reported clinical trials. © Georg Thieme Verlag KG Stuttgart · New York.

Symmetric operation of the resonant exchange qubit

NASA Astrophysics Data System (ADS)

Malinowski, Filip K.; Martins, Frederico; Nissen, Peter D.; Fallahi, Saeed; Gardner, Geoffrey C.; Manfra, Michael J.; Marcus, Charles M.; Kuemmeth, Ferdinand

2017-07-01

We operate a resonant exchange qubit in a highly symmetric triple-dot configuration using IQ-modulated rf pulses. We find that the qubit splitting is an order of magnitude less sensitive to all relevant control voltages, compared to the conventional operating point, but we observe no significant improvement in the quality of Rabi oscillations. For weak driving this is consistent with Overhauser field fluctuations modulating the qubit splitting. For strong driving we infer that effective voltage noise modulates the coupling strength between rf drive and the qubit, thereby quickening Rabi decay. Application of CPMG dynamical decoupling sequences consisting of up to 32 π pulses significantly prolongs qubit coherence, leading to marginally longer dephasing times in the symmetric configuration. This is consistent with dynamical decoupling from low frequency noise, but quantitatively cannot be explained by effective gate voltage noise and Overhauser field fluctuations alone. Our results inform recent strategies for the utilization of symmetric configurations in the operation of triple-dot qubits.

Computer model to simulate testing at the National Transonic Facility

NASA Technical Reports Server (NTRS)

Mineck, Raymond E.; Owens, Lewis R., Jr.; Wahls, Richard A.; Hannon, Judith A.

1995-01-01

A computer model has been developed to simulate the processes involved in the operation of the National Transonic Facility (NTF), a large cryogenic wind tunnel at the Langley Research Center. The simulation was verified by comparing the simulated results with previously acquired data from three experimental wind tunnel test programs in the NTF. The comparisons suggest that the computer model simulates reasonably well the processes that determine the liquid nitrogen (LN2) consumption, electrical consumption, fan-on time, and the test time required to complete a test plan at the NTF. From these limited comparisons, it appears that the results from the simulation model are generally within about 10 percent of the actual NTF test results. The use of actual data acquisition times in the simulation produced better estimates of the LN2 usage, as expected. Additional comparisons are needed to refine the model constants. The model will typically produce optimistic results since the times and rates included in the model are typically the optimum values. Any deviation from the optimum values will lead to longer times or increased LN2 and electrical consumption for the proposed test plan. Computer code operating instructions and listings of sample input and output files have been included.

The effects of time delays on a telepathology user interface.

PubMed Central

Carr, D.; Hasegawa, H.; Lemmon, D.; Plaisant, C.

1992-01-01

Telepathology enables a pathologist to examine physically distant tissue samples by microscope operation over a communication link. Communication links can impose time delays which cause difficulties in controlling the remote device. Such difficulties were found in a microscope teleoperation system. Since the user interface is critical to pathologist's acceptance of telepathology, we redesigned the user interface for this system, built two different versions (a keypad whose movement commands operated by specifying a start command followed by a stop command and a trackball interface whose movement commands were incremental and directly proportional to the rotation of the trackball). We then conducted a pilot study to determine the effect of time delays on the new user interfaces. In our experiment, the keypad was the faster interface when the time delay is short. There was no evidence to favor either the keypad or trackball when the time delay was longer. Inexperienced participants benefitted by allowing them to move long distances over the microscope slide by dragging the field-of-view indicator on the touchscreen control panel. The experiment suggests that changes could be made to the trackball interface which would improve its performance. PMID:1482878

Suited versus unsuited analog astronaut performance using the Aouda.X space suit simulator: the DELTA experiment of MARS2013.

PubMed

Soucek, Alexander; Ostkamp, Lutz; Paternesi, Roberta

2015-04-01

Space suit simulators are used for extravehicular activities (EVAs) during Mars analog missions. Flight planning and EVA productivity require accurate time estimates of activities to be performed with such simulators, such as experiment execution or traverse walking. We present a benchmarking methodology for the Aouda.X space suit simulator of the Austrian Space Forum. By measuring and comparing the times needed to perform a set of 10 test activities with and without Aouda.X, an average time delay was derived in the form of a multiplicative factor. This statistical value (a second-over-second time ratio) is 1.30 and shows that operations in Aouda.X take on average a third longer than the same operations without the suit. We also show that activities predominantly requiring fine motor skills are associated with larger time delays (between 1.17 and 1.59) than those requiring short-distance locomotion or short-term muscle strain (between 1.10 and 1.16). The results of the DELTA experiment performed during the MARS2013 field mission increase analog mission planning reliability and thus EVA efficiency and productivity when using Aouda.X.

Substrate effects on pupation and adult emergence of Hermetia illucens (Diptera: Stratiomyidae).

PubMed

Holmes, L A; Vanlaerhoven, S L; Tomberlin, J K

2013-04-01

Black soldier flies, Hermetia illucens (L.) (Diptera: Stratiomyidae), are of particular interest for their applications in waste management. Feeding on decaying organic waste, black soldier flies successfully reduce manure in confined animal feeding operations of poultry, swine, and cattle. To optimize waste conversion in confined animal feeding operations and landfill facilities, it is imperative to optimize black soldier fly development. Unfortunately, black soldier flies only convert waste during their larval feeding stages and therefore it is of interest to optimize the nonfeeding stages of development, specifically, the postfeeding and pupal stages. The time spent in these stages is thought to be determined by the pupation substrate encountered by the postfeeding larvae. The objective of this study was to determine the effect different pupation substrates have on postfeeding development time, pupation time, and adult emergence success. Five pupation substrates were compared: wood shavings, potting soil, topsoil, sand, and nothing. Postfeeding larvae took longer to reach pupation in the absence of a pupation substrate, although reaching pupation in the shortest time in potting soil and wood shavings. The time spent in the pupal stage was shortest in the absence of a pupation substrate. However, fewer adults emerged when a pupation substrate was not provided.

Haul truck tire dynamics due to tire condition

NASA Astrophysics Data System (ADS)

Vaghar Anzabi, R.; Nobes, D. S.; Lipsett, M. G.

2012-05-01

Pneumatic tires are costly components on large off-road haul trucks used in surface mining operations. Tires are prone to damage during operation, and these events can lead to injuries to personnel, loss of equipment, and reduced productivity. Damage rates have significant variability, due to operating conditions and a range of tire fault modes. Currently, monitoring of tire condition is done by physical inspection; and the mean time between inspections is often longer than the mean time between incipient failure and functional failure of the tire. Options for new condition monitoring methods include off-board thermal imaging and camera-based optical methods for detecting abnormal deformation and surface features, as well as on-board sensors to detect tire faults during vehicle operation. Physics-based modeling of tire dynamics can provide a good understanding of the tire behavior, and give insight into observability requirements for improved monitoring systems. This paper describes a model to simulate the dynamics of haul truck tires when a fault is present to determine the effects of physical parameter changes that relate to faults. To simulate the dynamics, a lumped mass 'quarter-vehicle' model has been used to determine the response of the system to a road profile when a failure changes the original properties of the tire. The result is a model of tire vertical displacement that can be used to detect a fault, which will be tested under field conditions in time-varying conditions.

Time-dependent constitutive modeling of drive belts—II. The effect of the shape of material retardation spectrum on the strain accumulation process

NASA Astrophysics Data System (ADS)

Zupančič, B.; Emri, I.

2009-11-01

This is the second paper in the series addressing the constitutive modeling of dynamically loaded elastomeric products such as power transmission belts. During the normal operation of such belts certain segments of the belt structure are loaded via tooth-like cyclical loading. When the time-dependent properties of the elastomeric material “match” the time-scale of the dynamic loading a strain accumulation (incrementation) process occurs. It was shown that the location of a critical rotation speed strongly depends on the distribution (shape) of the retardation spectrum, whereas the magnitude of the accumulated strain is governed by the strength of the corresponding spectrum lines. These interrelations are extremely non-linear. The strain accumulation process is most intensive at the beginning of the drive belt operation, and is less intensive for longer belts. The strain accumulation process is governed by the spectrum lines that are positioned within a certain region, which we call the Strain Accumulation Window (SAW). An SAW is always located to the right of the spectrum line, L i , at log ( ω λ i )=0, where ω is the operational angular velocity. The width of the SAW depends on the width of the material spectrum. Based on the following analysis a new designing criterion is proposed for use in engineering applications for selecting a proper material for general drive-belt operations.

Surgical outcomes of laparoscopic hysterectomy with concomitant endometriosis without bowel or bladder dissection: a cohort analysis to define a case-mix variable.

PubMed

Sandberg, Evelien M; Driessen, Sara R C; Bak, Evelien A T; van Geloven, Nan; Berger, Judith P; Smeets, Mathilde J G H; Rhemrev, Johann P T; Jansen, Frank Willem

2018-01-01

Pelvic endometriosis is often mentioned as one of the variables influencing surgical outcomes of laparoscopic hysterectomy (LH). However, its additional surgical risks have not been well established. The aim of this study was to analyze to what extent concomitant endometriosis influences surgical outcomes of LH and to determine if it should be considered as case-mix variable. A total of 2655 LH's were analyzed, of which 397 (15.0%) with concomitant endometriosis. For blood loss and operative time, no measurable association was found for stages I ( n  = 106) and II ( n  = 103) endometriosis compared to LH without endometriosis. LH with stages III ( n  = 93) and IV ( n  = 95) endometriosis were associated with more intra-operative blood loss ( p  = < .001) and a prolonged operative time ( p  = < .001) compared to LH without endometriosis. No significant association was found between endometriosis (all stages) and complications ( p  = .62). The findings of our study have provided numeric support for the influence of concomitant endometriosis on surgical outcomes of LH, without bowel or bladder dissection. Only stages III and IV were associated with a longer operative time and more blood loss and should thus be considered as case-mix variables in future quality measurement tools.

The effect of intermittent operation on a wind-powered membrane system for brackish water desalination.

PubMed

Park, G L; Schäfer, A I; Richards, B S

2012-01-01

Renewable energy powered membrane systems that are directly-connected must take account of both the inherent fluctuations and the intermittency of the energy resource. In order to determine the effect of intermittent operation, a membrane system was tested with variables of (i) amplitude from 60 to 300 W and (ii) length of time with no power from 0.5 to 3 min. This was performed over one hour periods with six on/off cycles to simulate the system operating under intermittent operation for short periods of time when directly-connected to a small wind turbine. The setup used a Filmtec BW30-4040 brackish water reverse osmosis membrane with feed waters of 2,750 mg/L and 5,500 mg/L NaCl. The results showed that the membrane system produced potable water under the majority of intermittency experiments performed. There was a relatively large increase in the average salt concentration of the permeate, especially when the system was off for shorter periods of time (0.5-1 min). Longer periods of no power (1-3 min) did not have as significant an effect on the average water quality. This is important when the need for energy buffering or short term storage is considered for these systems as it shows the potential for improving the overall flux and water quality using temporary energy storage.

Diode laser surgery. Ab interno and ab externo versus conventional surgery in rabbits.

PubMed

Karp, C L; Higginbotham, E J; Edward, D P; Musch, D C

1993-10-01

Fibroblastic proliferation of subconjunctival tissues remains a primary mechanism of failure in filtration surgery. Minimizing the surgical manipulation of episcleral tissues may reduce scarring. Laser sclerostomy surgery involves minimal tissue dissection, and is gaining attention as a method of potentially improving filter duration in high-risk cases. Twenty-five New Zealand rabbits underwent filtration surgery in one eye, and the fellow eye remained as the unoperated control. Ten rabbits underwent ab externo diode laser sclerostomy surgery, ten underwent ab interno diode sclerostomy surgery, and five had posterior sclerostomy procedures. Filtration failure was defined as a less-than-4-mmHg intraocular pressure (IOP) difference between the operative and control eyes. The mean time to failure for the ab externo, ab interno, and conventional posterior sclerostomy techniques measured 17.4 +/- 11.5, 13.1 +/- 6.7, and 6.0 +/- 3.1 days, respectively. In a comparison of the laser-treated groups with the conventional procedure, the time to failure was significantly longer (P = 0.02) for the ab externo filter. The mean ab interno sclerostomy duration was longer than the posterior lip procedure, but this difference was not statistically significant (P = 0.15). The overall level of IOP reduction was similar in the three groups. These data suggest that diode laser sclerostomy is a feasible technique in rabbits, and the ab externo approach resulted in longer filter duration than the conventional posterior lip procedure in this model.

78 FR 52753 - Taking of Marine Mammals Incidental to Commercial Fishing Operations; Harbor Porpoise Take...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-26

... area target bycatch rates no longer accurately reflect compliant bycatch rates in New England. As... necessary to prevent the improper triggering of consequence closure areas based on target harbor porpoise bycatch rates that no longer accurately reflect actual bycatch in New England sink gillnets due to fishery...

Effect of mechanical load on the shuttling operation of molecular muscles

NASA Astrophysics Data System (ADS)

Lee, Seungjun; Lu, Wei

2009-06-01

We use molecular dynamics simulations to investigate the effect of mechanical force on stimulus-induced deformation of rotaxane-based artificial molecular muscles. The study shows that a small external force slows down the shuttling motion and leads to longer actuation time for a muscle to reach its full extension. Further increase in the force can significantly reduce the traveling distance of the ring, leading to reduced strain output. A force larger than 28 pN can completely suppress the shuttling motion, suggesting a limit of force output of molecular muscles.

Low power signal processing electronics for wearable medical devices.

PubMed

Casson, Alexander J; Rodriguez-Villegas, Esther

2010-01-01

Custom designed microchips, known as Application Specific Integrated Circuits (ASICs), offer the lowest possible power consumption electronics. However, this comes at the cost of a longer, more complex and more costly design process compared to one using generic, off-the-shelf components. Nevertheless, their use is essential in future truly wearable medical devices that must operate for long periods of time from physically small, energy limited batteries. This presentation will demonstrate the state-of-the-art in ASIC technology for providing online signal processing for use in these wearable medical devices.

Acoustic systems for the measurement of streamflow

USGS Publications Warehouse

Laenen, Antonius; Smith, Winchell

1983-01-01

The acoustic velocity meter (AVM), also referred to as an ultrasonic flowmeter, has been an operational tool for the measurement of streamflow since 1965. Very little information is available concerning AVM operation, performance, and limitations. The purpose of this report is to consolidate information in such a manner as to provide a better understanding about the application of this instrumentation to streamflow measurement. AVM instrumentation is highly accurate and nonmechanical. Most commercial AVM systems that measure streamflow use the time-of-travel method to determine a velocity between two points. The systems operate on the principle that point-to-point upstream travel-time of sound is longer than the downstream travel-time, and this difference can be monitored and measured accurately by electronics. AVM equipment has no practical upper limit of measurable velocity if sonic transducers are securely placed and adequately protected. AVM systems used in streamflow measurement generally operate with a resolution of ?0.01 meter per second but this is dependent on system frequency, path length, and signal attenuation. In some applications the performance of AVM equipment may be degraded by multipath interference, signal bending, signal attenuation, and variable streamline orientation. Presently used minicomputer systems, although expensive to purchase and maintain, perform well. Increased use of AVM systems probably will be realized as smaller, less expensive, and more conveniently operable microprocessor-based systems become readily available. Available AVM equipment should be capable of flow measurement in a wide variety of situations heretofore untried. New signal-detection techniques and communication linkages can provide additional flexibility to the systems so that operation is possible in more river and estuary situations.

Costs and benefits of different methods of esophagectomy for esophageal cancer.

PubMed

Yanasoot, Alongkorn; Yolsuriyanwong, Kamtorn; Ruangsin, Sakchai; Laohawiriyakamol, Supparerk; Sunpaweravong, Somkiat

2017-01-01

Background A minimally invasive approach to esophagectomy is being used increasingly, but concerns remain regarding the feasibility, safety, cost, and outcomes. We performed an analysis of the costs and benefits of minimally invasive, hybrid, and open esophagectomy approaches for esophageal cancer surgery. Methods The data of 83 consecutive patients who underwent a McKeown's esophagectomy at Prince of Songkla University Hospital between January 2008 and December 2014 were analyzed. Open esophagectomy was performed in 54 patients, minimally invasive esophagectomy in 13, and hybrid esophagectomy in 16. There were no differences in patient characteristics among the 3 groups Minimally invasive esophagectomy was undertaken via a thoracoscopic-laparoscopic approach, hybrid esophagectomy via a thoracoscopic-laparotomy approach, and open esophagectomy by a thoracotomy-laparotomy approach. Results Minimally invasive esophagectomy required a longer operative time than hybrid or open esophagectomy ( p = 0.02), but these patients reported less postoperative pain ( p = 0.01). There were no significant differences in blood loss, intensive care unit stay, hospital stay, or postoperative complications among the 3 groups. Minimally invasive esophagectomy incurred higher operative and surgical material costs than hybrid or open esophagectomy ( p = 0.01), but there were no significant differences in inpatient care and total hospital costs. Conclusion Minimally invasive esophagectomy resulted in the least postoperative pain but the greatest operative cost and longest operative time. Open esophagectomy was associated with the lowest operative cost and shortest operative time but the most postoperative pain. Hybrid esophagectomy had a shorter learning curve while sharing the advantages of minimally invasive esophagectomy.

The relationship of physical trauma and surgical stress to menstrual dysfunction.

PubMed

To, W W; Wong, M W

2000-02-01

To evaluate the incidence and pattern of menstrual dysfunction in reproductive age group women suffering acute musculoskeletal trauma, 198 women between 15 and 50 years of age admitted consecutively into an acute orthopaedic unit were recruited over a 6-month period. The patients were then followed up for 6 months with menstrual diaries to compare their menstrual pattern with their preadmission status. Excluding those with significant menstrual problems before admission, the menstrual pattern remained normal in 135 (68%) (EM), while 12 (6%) developed polymenorrhoea (PM), and 51 (25%) had oligomenorrhoea or amenorrhoea (OAM) within the 6-month observation. The three groups did not differ in their mean age, body mass index, parity or age of menarche, but previous cycle lengths were shortest in the PM group (25.4 days, SD 7.64) (p<0.05) and history of amenorrhoea in the previous one year was most common in the OAM group (p<0.025). Univariate analysis showed the incidence of moderate to major trauma,operative treatment, longer operative time, general anaesthesia, blood transfusion and immobilisation were significantly higher in the PM and OAM groups compared to the unchanged group (p<0.05). A logistic regression model showed that general anaesthesia and longer surgical operations remained significantly related to the development of menstrual dysfunction. We conclude that the pattern of menstrual dysfunction after acute orthopaedic trauma appeared to be dictated by the woman's pre-existing menstrual characteristics and the stress of surgical treatment.

Novel Long Stroke Reciprocating Compressor for Energy Efficient Jaggery Making

NASA Astrophysics Data System (ADS)

Rane, M. V.; Uphade, D. B.

2017-08-01

Novel Long Stroke Reciprocating Compressor is analysed for jaggery making while avoiding burning of bagasse for concentrating juice. Heat of evaporated water vapour along with small compressor work is recycled to enable boiling of juice. Condensate formed during heating of juice is pure water, as oil-less compressor is used. Superheat of compressor is suppressed by flow of superheated vapours through condensate. It limits heating surface temperature and avoids caramelization of sugar. Thereby improves quality of jaggery and eliminates need to use chemicals for colour improvement. Stroke to bore ratio is 0.6 to 1.2 in conventional reciprocating drives. Long stroke in reciprocating compressors enhances heat dissipation to surrounding by providing large surface area and increases isentropic efficiency by reducing compressor outlet temperature. Longer stroke increases inlet and exit valve operation timings, which reduces inertial effects substantially. Thereby allowing use of sturdier valves. This enables handling liquid along with vapour in compressors. Thereby supressing the superheat and reducing compressor power input. Longer stroke increases stroke to clearance ratios which increases volumetric efficiency and ability of compressor to compress through higher pressure ratios efficiently. Stress-strain simulation is performed in SolidWorks for gear drive. Long Stroke Reciprocating Compressor is developed at Heat Pump Laboratory, stroke/bore 292 mm/32 mm. It is operated and tested successfully at different speeds for operational stability of components. Theoretical volumetric efficiency is 93.9% at pressure ratio 2.0. Specific energy consumption is 108.3 kWhe/m3 separated water, considering free run power.

A novel microfluidics-based method for probing weak protein-protein interactions.

PubMed

Tan, Darren Cherng-wen; Wijaya, I Putu Mahendra; Andreasson-Ochsner, Mirjam; Vasina, Elena Nikolaevna; Nallani, Madhavan; Hunziker, Walter; Sinner, Eva-Kathrin

2012-08-07

We report the use of a novel microfluidics-based method to detect weak protein-protein interactions between membrane proteins. The tight junction protein, claudin-2, synthesised in vitro using a cell-free expression system in the presence of polymer vesicles as membrane scaffolds, was used as a model membrane protein. Individual claudin-2 molecules interact weakly, although the cumulative effect of these interactions is significant. This effect results in a transient decrease of average vesicle dispersivity and reduction in transport speed of claudin-2-functionalised vesicles. Polymer vesicles functionalised with claudin-2 were perfused through a microfluidic channel and the time taken to traverse a defined distance within the channel was measured. Functionalised vesicles took 1.19 to 1.69 times longer to traverse this distance than unfunctionalised ones. Coating the channel walls with protein A and incubating the vesicles with anti-claudin-2 antibodies prior to perfusion resulted in the functionalised vesicles taking 1.75 to 2.5 times longer to traverse this distance compared to the controls. The data show that our system is able to detect weak as well as strong protein-protein interactions. This system offers researchers a portable, easily operated and customizable platform for the study of weak protein-protein interactions, particularly between membrane proteins.

Predictors of Complications in Patients Receiving Head and Neck Free Flap Reconstructive Procedures.

PubMed

Eskander, Antoine; Kang, Stephen; Tweel, Ben; Sitapara, Jigar; Old, Matthew; Ozer, Enver; Agrawal, Amit; Carrau, Ricardo; Rocco, James W; Teknos, Theodoros N

2018-05-01

Objective To (1) determine the overall complication rate, wound healing, and wound infection complications and (2) identify preoperative, intraoperative, and postoperative predictors of these complications. Study Design Case series with chart review. Setting Tertiary academic cancer hospital. Subjects and Methods All head and neck free flap patients at The Ohio State University (2006-2012) were assessed. Multivariable logistic regression assessed the impact of patient factors, flap and wound factors, and intraoperative factors on the aforementioned quality metric outcomes. Results Of the 515 patients identified, 54% had a complication predicted by longer operating room (OR) time, higher comorbidity index, and oral cavity and pharyngeal tumor sites. Predictors of wound-healing complications (15%) were longer OR time, volume of crystalloid given intraoperatively, and oral cavity and pharyngeal tumor sites. Predictors of wound infection (12%) were younger age, diabetes mellitus, and malnutrition. Conclusions Wound healing and infectious complications account for most complications in patients with head and neck cancer undergoing free flap reconstruction. Clean contaminated wounds are a significant predictor of wound complications. Advanced OR time, advanced age, and comorbidity status, including diabetes mellitus and malnutrition, are other important predictors. Crystalloid administration is also an important predictor of wound-healing complications, and this warrants further study.

Study of thermally-induced optical bistability and the role of surface treatments in Si-based mid-infrared photonic crystal cavities.

PubMed

Shankar, Raji; Bulu, Irfan; Leijssen, Rick; Lončar, Marko

2011-11-21

We report the observation of optical bistability in Si-based photonic crystal cavities operating around 4.5 µm. Time domain measurements indicate that the source of this optical bistability is thermal, with a time constant on the order of 5 µs. Quality (Q) factor improvement is shown by the use of surface treatments (wet processes and annealing), resulting in a significant increase in Q-factor, which in our best devices is on the order of ~45,000 at 4.48 µm. After annealing in a N(2) environment, optical bistability is no longer seen in our cavities. © 2011 Optical Society of America

An Assessment of Fixed Interval Timing in Free-Flying Honey Bees (Apis mellifera ligustica): An Analysis of Individual Performance

PubMed Central

Craig, David Philip Arthur; Varnon, Christopher A.; Sokolowski, Michel B. C.; Wells, Harrington; Abramson, Charles I.

2014-01-01

Interval timing is a key element of foraging theory, models of predator avoidance, and competitive interactions. Although interval timing is well documented in vertebrate species, it is virtually unstudied in invertebrates. In the present experiment, we used free-flying honey bees (Apis mellifera ligustica) as a model for timing behaviors. Subjects were trained to enter a hole in an automated artificial flower to receive a nectar reinforcer (i.e. reward). Responses were continuously reinforced prior to exposure to either a fixed interval (FI) 15-sec, FI 30-sec, FI 60-sec, or FI 120-sec reinforcement schedule. We measured response rate and post-reinforcement pause within each fixed interval trial between reinforcers. Honey bees responded at higher frequencies earlier in the fixed interval suggesting subject responding did not come under traditional forms of temporal control. Response rates were lower during FI conditions compared to performance on continuous reinforcement schedules, and responding was more resistant to extinction when previously reinforced on FI schedules. However, no “scalloped” or “break-and-run” patterns of group or individual responses reinforced on FI schedules were observed; no traditional evidence of temporal control was found. Finally, longer FI schedules eventually caused all subjects to cease returning to the operant chamber indicating subjects did not tolerate the longer FI schedules. PMID:24983960

Open versus laparoscopic appendectomy.

PubMed

Herman, J; Duda, M; Lovecek, M; Svach, I

2003-01-01

To asses the role of laparoscopic appendectomy in the treatment of acute as well as chronic appendicitis on the basis of our own experiences. From the set of 849 patients treated with appendectomy (from January 1993 to December 2000) 331 were singled out, i.e.; those unable to work for some time and thus being on sickness benefit who asked for a medical certificate. They were operated on for either acute or chronic appendicitis. In our set of 331 patients (158 males, 173 females, the average age 29.4) open appendectomy was performed on 179 patients and laparoscopic appendectomy on 152. Laparoscopic appendectomy was performed in 43 males (28%) and 109 females (72%); open appendectomy in 115 males (64%) and 64 females (36%). Laparoscopic appendectomy took 53.7 +/- 18.1 minutes, open appendectomy took 43.6 +/- 8.99 minutes. The time of work disablement is longer in open appendectomy (open appendectomy: 41.2 +/- 9.91 days; laparoscopic appendectomy; 29.1 +/- 15.11 days). A significant difference (p < 0.00001) can be seen in the length of hospitalization (laparoscopic appendectomy: 5.0 +/- 2.75 days, open appendectomy: 8.3 +/- 2.83 days). Patients who undergo laparoscopic appendectomy spent less time in hospital, and they can return to work rather earlier. On the other hand the time of surgery is longer. Higher cost is compensated for with shorter hospitalization and early return to work.

Dioxins from medical waste incineration: Normal operation and transient conditions.

PubMed

Chen, Tong; Zhan, Ming-xiu; Yan, Mi; Fu, Jian-ying; Lu, Sheng-yong; Li, Xiao-dong; Yan, Jian-hua; Buekens, Alfons

2015-07-01

Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) are key pollutants in waste incineration. At present, incinerator managers and official supervisors focus only on emissions evolving during steady-state operation. Yet, these emissions may considerably be raised during periods of poor combustion, plant shutdown, and especially when starting-up from cold. Until now there were no data on transient emissions from medical (or hospital) waste incineration (MWI). However, MWI is reputed to engender higher emissions than those from municipal solid waste incineration (MSWI). The emission levels in this study recorded for shutdown and start-up, however, were significantly higher: 483 ± 184 ng Nm(-3) (1.47 ± 0.17 ng I-TEQ Nm(-3)) for shutdown and 735 ng Nm(-3) (7.73 ng I-TEQ Nm(-3)) for start-up conditions, respectively. Thus, the average (I-TEQ) concentration during shutdown is 2.6 (3.8) times higher than the average concentration during normal operation, and the average (I-TEQ) concentration during start-up is 4.0 (almost 20) times higher. So monitoring should cover the entire incineration cycle, including start-up, operation and shutdown, rather than optimised operation only. This suggestion is important for medical waste incinerators, as these facilities frequently start up and shut down, because of their small size, or of lacking waste supply. Forthcoming operation should shift towards much longer operating cycles, i.e., a single weekly start-up and shutdown. © The Author(s) 2015.

40 CFR 258.61 - Post-closure care requirements.

Code of Federal Regulations, 2010 CFR

2010-07-01

... the final cover; (2) Maintaining and operating the leachate collection system in accordance with the...) Maintaining and operating the gas monitoring system in accordance with the requirements of § 258.23. (b) The... stop managing leachate if the owner or operator demonstrates that leachate no longer poses a threat to...

Life and Operating Range Extension of the BPT-4000 Qualification Model Hall Thruster

NASA Technical Reports Server (NTRS)

Welander, Ben; Carpenter, Christian; deGrys, Kristi; Hofer, Richard R.; Randolph, Thomas M.; Manzella, David H.

2006-01-01

Following completion of the 5,600 hr qualification life test of the BPT-4000 4.5 kW Hall Thruster Propulsion System, NASA and Aerojet have undertaken efforts to extend the qualified operating range and lifetime of the thruster to support a wider range of NASA missions. The system was originally designed for orbit raising and stationkeeping applications on military and commercial geostationary satellites. As such, it was designed to operate over a range of power levels from 3 to 4.5 kW. Studies of robotic exploration applications have shown that the cost savings provided by utilizing commercial technology that can operate over a wider range of power levels provides significant mission benefits. The testing reported on here shows that the 4.5 kW thruster as designed has the capability to operate efficiently down to power levels as low as 1 kW. At the time of writing, the BPT-4000 qualification thruster and cathode have accumulated over 400 hr of operation between 1 to 2 kW with an additional 600 hr currently planned. The thruster has demonstrated no issues with longer duration operation at low power.

NASA Global Hawk: A New Tool for Earth Science Research

NASA Technical Reports Server (NTRS)

Naftel, J. Chris

2009-01-01

Scientists have eagerly anticipated the performance capability of the National Aeronautics and Space Administration (NASA) Global Hawk for over a decade. In 2009 this capability becomes operational. One of the most desired performance capabilities of the Global Hawk aircraft is very long endurance. The Global Hawk aircraft can remain airborne longer than almost all other jet-powered aircraft currently flying, and longer than all other aircraft available for airborne science use. This paper describes the NASA Global Hawk system, payload accommodations, concept of operations, and the first scientific data-gathering mission: Global Hawk Pacific 2009.

[The randomized controlled trial of influences of T shape approach on the function of knee joint in the treatment of proximal tibial fractures].

PubMed

Peng, Wei-xiong; Zhang, Zhi; Liang, Jie-hong

2008-04-01

To investigate the clinical value of T shape approach in the treatment of proximal tibial fractures. One handrend and thirteen patients of proximal tibial fractures were randomly divided into two groups. Group A: 62 cases underwent the traditional exposure approach. According to Schatzker classification,the cases of II to VI type was 25, 10, 16, 6, 5 respectively. Group B:51 cases underwent T shape approach ahead of knee joint, the cases of II to VI type was 21, 8, 13, 5, 4 respectively. All data were analyzed by SPSS 10.0 to compare operation time, blood loss, duration of hospitalization, healing time, the time of osseous union and complications after operation. Sixty patients in group A and 50 patients in group B were followed-up from 12 to 24 months. (1) Operation time:group B was longer than A (P < 0.01). (2) Mean blood loss and duration of hospitalization was the same. (3) Clinical healing time:group B was shorter. (4) Mean time of osseous union: 48 group B was shorter. Function of knee: group B was better than group A. (Complication: group B was less than group A. As compared with traditional exposure approach, T shape approach of knee joint had advantages of small scar, fewer complications, faster union of fracture and earlier recovery of joint function. The approach is valuable for the treatment of proximal tibial fractures.

A prospective, randomised trial comparing closed intramedullary nailing with percutaneous plating in the treatment of distal metaphyseal fractures of the tibia.

PubMed

Guo, J J; Tang, N; Yang, H L; Tang, T S

2010-07-01

We compared the outcome of closed intramedullary nailing with minimally invasive plate osteosynthesis using a percutaneous locked compression plate in patients with a distal metaphyseal fracture in a prospective study. A total of 85 patients were randomised to operative stabilisation either by a closed intramedullary nail (44) or by minimally invasive osteosynthesis with a compression plate (41). Pre-operative variables included the patients' age and the side and pattern of the fracture. Peri-operative variables were the operating time and the radiation time. Postoperative variables were wound problems, the time to union of the fracture, the functional American Orthopaedic Foot and Ankle surgery score and removal of hardware. We found no significant difference in the pre-operative variables or in the time to union in the two groups. However, the mean radiation time and operating time were significantly longer in the locked compression plate group (3.0 vs 2.12 minutes, p < 0.001, and 97.9 vs 81.2 minutes, p < 0.001, respectively).After one year, all the fractures had united. Patients who had intramedullary nailing had a higher mean pain score (40 = no pain, 0 = severe pain), [corrected] but better function, alignment and total American Orthopaedic Foot and Ankle surgery scores, although the differences were not statistically significant (p = 0.234, p = 0.157, p = 0.897, p = 0.177 respectively). Three (6.8%) patients in the intramedullary nailing group and six (14.6%) in the locked compression plate group showed delayed wound healing, and 37 (84.1%) in the former group and 38 (92.7%) in the latter group expressed a wish to have the implant removed. We conclude that both closed intramedullary nailing and a percutaneous locked compression plate can be used safely to treat Orthopaedic Trauma Association type-43A distal metaphyseal fractures of the tibia. However, closed intramedullary nailing has the advantage of a shorter operating and radiation time and easier removal of the implant. We therefore prefer closed intramedullary nailing for patients with these fractures.

Anesthetic complications in dogs undergoing hepatic surgery: cholecystectomy versus non-cholecystectomy.

PubMed

Burns, Brigid R; Hofmeister, Erik H; Brainard, Benjamin M

2014-03-01

To determine if dogs that undergo laparotomy for cholecystectomy suffer from a greater number or magnitude of perianesthetic complications, including hypotension, hypothermia, longer recovery time, and lower survival rate, than dogs that undergo laparotomy for hepatic surgery without cholecystectomy. Retrospective cohort study. One hundred and three dogs, anesthetised between January 2007 and October 2011. The variables collected from the medical record included age, weight, gender, surgical procedure, pre-operative bloodwork, American Society of Anesthesiologists (ASA) status, emergency status, total bilirubin concentration, anesthetic agents administered, body temperature nadir, final body temperature, hypotension, duration of hypotension, blood pressure nadir, intraoperative drugs, anesthesia duration, surgery duration, time to extubation, final diagnosis, days spent in the intensive care unit (ICU), total bill, survival to discharge, and survival to follow-up. No significant difference in body temperature nadir, final temperature, presence of hypotension, duration of hypotension, blood pressure nadir, the use of inotropes, or final outcome was found between dogs undergoing cholecystectomy and dogs undergoing exploratory laparotomy for other hepatic disease. Dogs that had cholecystectomy had longer anesthesia durations and longer surgery durations than dogs that did not have cholecystectomy. No significant differences existed for temperature nadir (34.8 versus 35.3°C; non-cholecystectomy versus cholecystectomy), final temperature (35.6 versus 35.9°C), time to extubation (30 versus 49 minutes), duration of hypotension (27 versus 21 minutes), or MAP nadir (56 versus 55 mmHg). Hypotension occurred in 66% and 74% and inotropes were used in 64% and 53%, for non-cholecystectomy and cholecystectomy patients, respectively. Dogs that underwent cholecystectomies did not suffer a greater number of anesthesia complications than did dogs undergoing hepatic surgery without cholecystectomies. © 2013 Association of Veterinary Anaesthetists and the American College of Veterinary Anesthesia and Analgesia.

Designing software for operational decision support through coloured Petri nets

NASA Astrophysics Data System (ADS)

Maggi, F. M.; Westergaard, M.

2017-05-01

Operational support provides, during the execution of a business process, replies to questions such as 'how do I end the execution of the process in the cheapest way?' and 'is my execution compliant with some expected behaviour?' These questions may be asked several times during a single execution and, to answer them, dedicated software components (the so-called operational support providers) need to be invoked. Therefore, an infrastructure is needed to handle multiple providers, maintain data between queries about the same execution and discard information when it is no longer needed. In this paper, we use coloured Petri nets (CPNs) to model and analyse software implementing such an infrastructure. This analysis is needed to clarify the requirements before implementation and to guarantee that the resulting software is correct. To this aim, we present techniques to represent and analyse state spaces with 250 million states on a normal PC. We show how the specified requirements have been implemented as a plug-in of the process mining tool ProM and how the operational support in ProM can be used in combination with an existing operational support provider.

Surgery for Patients With Recalcitrant Plantar Fasciitis

PubMed Central

Wheeler, Patrick; Boyd, Kevin; Shipton, Mary

2014-01-01

Background: Plantar fasciitis is a common cause of foot pain, and although many episodes are self-limiting with short duration, 10% leave chronic symptoms. Recalcitrant cases can be managed surgically, with studies demonstrating good results in the short term but uncertainties over longer term outcomes. Purpose: To assess the outcome following surgical intervention for patients with plantar fasciitis. Study Design: Case series; Level of evidence, 4. Methods: Seventy-nine patients were identified from operative diaries undergoing plantar fasciotomy surgery between 1993 and 2009. They were contacted to investigate long-term results using self-reported outcome measures. Results: Sixty-eight responses were received (86% response rate), with an average of 7 years (range, 1-15 years) of follow-up. Patients reported an average reduction in pain by visual analog scale of 79%, and 84% of patients were happy with the surgical results. Greater success was achieved in patients with shorter duration of symptoms preoperatively. No deterioration in success was seen over time. Conclusion: Plantar fasciotomy surgery for plantar fasciitis remains controversial, with biomechanical arguments against surgery; however, this article reports good success following surgery over a long follow-up period. The results of current operative techniques need to be fully investigated for longer term success, as do the outcomes of newer nonoperative management strategies. PMID:26535314

78 FR 67402 - Biweekly Notice; Applications and Amendments to Facility Operating Licenses and Combined Licenses...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-11-12

... the requirement for organizational independence of the operations, health physics, and quality... personnel will no longer be required to protect public health and safety. 1. Does the proposed change...

[Unidirectional versus multidirectional palmar locking osteosynthesis of unstable distal radius fractures: comparative analysis with LDR 2.4 mm versus 2.7 mm matrix-Smartlock].

PubMed

Hakimi, M; Jungbluth, P; Gehrmann, S; Nowak, J; Windolf, J; Wild, M

2010-03-01

Due to advances in the development of the unidirectional locking plates there is now an increased use of multidirectional palmar locking plates in the treatment of distal radius factures. The purpose of this study was to evaluate a possible improvement of the treatment and results. This prospective cohort study investigated 40 patients with C1 and C2 Colles' fractures who had been treated with unidirectional and multidirectional locking plates. The average time for the follow-up examinations was 12.3 months (range 12-15 months) after surgery. The intra-operative functional (neutral-zero method), radiological and subjective (DASH score, VAS) results were evaluated. The intra-operative fluoroscopy time of the unidirectional group was 58 s shorter compared to the multidirectional group. All fractures healed without any complication. The radiological, subjective (DASH score) and objective results for both groups were good and showed no differences. Unidirectional palmar locking plates are equally suited for the therapy of C1 and C2 fractures as multidirectional palmar locking plates but multidirectional plates require a longer fluoroscopy time.

Membrane properties change in fine-pore aeration diffusers: full-scale variations of transfer efficiency and headloss.

PubMed

Rosso, Diego; Libra, Judy A; Wiehe, Wolfgang; Stenstrom, Michael K

2008-05-01

Fine-pore diffusers are the most common aeration system in municipal wastewater treatment. Punched polymeric membranes are often used in fine-pore aeration due to their advantageous initial performance. These membranes are subject to fouling and scaling, resulting in increased headloss and reduced oxygen transfer efficiency, both contributing to increased plant energy costs. This paper describes and discusses the change in material properties for polymeric fine-pore diffusers, comparing new and used membranes. Three different diffuser technologies were tested and sample diffusers from two wastewater treatment facilities were analysed. The polymeric membranes analysed in this paper were composed of ethylene-propylene-diene monomer (EPDM), polyurethane, and silicon. Transfer efficiency is usually lower with longer times in operation, as older, dilated orifices produce larger bubbles, which are unfavourable to mass transfer. At the same time, headloss increases with time in operation, since membranes increase in rigidity and hardness, and fouling and scaling phenomena occur at the orifice opening. Change in polymer properties and laboratory test results correlate with the decrease in oxygen transfer efficiency.

Pressurization and expulsion of a flightweight liquid hydrogen tank

NASA Technical Reports Server (NTRS)

Vandresar, N. T.; Stochl, R. J.

1993-01-01

Experimental results are presented for pressurization and expulsion of a flight-weight 4.89 cu m liquid hydrogen storage tank under normal gravity conditions. Pressurization and expulsion times are parametrically varied to study the effects of longer transfer times expected in future space flight applications. It is found that the increase in pressurant consumption with increased operational time is significant at shorter pressurization or expulsion durations and diminishes as the duration lengthens. Gas-to-wall heat transfer in the ullage is the dominant mode of energy exchange, with more than 50 percent of the pressurant energy being lost to tank wall heating in expulsions and the long duration pressurizations. Advanced data analysis will require a multidimensional approach combined with improved measurement capabilities of liquid-vapor interfacial transport phenomena.

Effect of Gastrointestinal Malformations on the Outcomes of Patients With Congenital Heart Disease.

PubMed

Mery, Carlos M; De León, Luis E; Rodriguez, J Rubén; Nieto, R Michael; Zhang, Wei; Adachi, Iki; Heinle, Jeffrey S; Kane, Lauren C; McKenzie, E Dean; Fraser, Charles D

2017-11-01

The goal of this study was to assess the effect of associated gastrointestinal malformations (GI) on the outcomes of patients undergoing congenital heart operations. Neonates and infants with thoracic (esophageal atresia, tracheoesophageal fistula) and abdominal (duodenal stenosis/atresia, imperforate anus, Hirschsprung disease) GI malformations undergoing congenital heart operations between 1995 and 2015 were included. Two control groups were created, one for each group. Patients were matched by diagnosis, procedure, history of prematurity, presence of genetic syndrome, and a propensity score including weight and year of operation. The cohort included 383 patients: 52 (14%) with thoracic GI malformations and 98 (25%) thoracic GI controls, 80 (21%) with abdominal GI malformations and 153 (40%) abdominal GI controls. Median follow-up was 6 years (range, 16 days to 20 years). Patients with thoracic GI malformations had longer length of stay (p < 0.001), longer intubation times (p = 0.002), and higher perioperative death (p = 0.015) than controls. There was a tendency for worse overall survival than controls, mainly explained by the higher risk of early death (p = 0.06). No difference was found in outcomes between patients with abdominal GI malformations and controls. Patients with thoracic GI malformations have worse perioperative outcomes than controls, but their long-term survival does not seem to be significantly different. Abdominal GI malformations do not have a significant effect on outcomes. The presence of GI malformations should likely not preclude patients from undergoing congenital heart operations, but careful family counseling is necessary, especially for thoracic GI malformations. Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

76 FR 65118 - Drawbridge Operation Regulation; Bear Creek, Sparrows Point, MD

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-20

... the openings of the drawbridge. After 1998, because the bridge can no longer be opened, there became no need for a regulation governing openings. It has come to the attention of the Coast Guard that the... requirements for the opening of a bridge that, in fact, can no longer open. This change does not affect vessel...

Defense.gov Special Report: Defense Officials Release Operational Energy

Science.gov Websites

Strategy You have reached a collection of archived material. The content available is no longer being updated and may no longer be applicable as a result of changes in law, regulation and/or the Army, teams of quiet professionals are lightening the load of soldiers on the ground and

Quantifying Risk for Decentralized Offensive Cyber Operations

DTIC Science & Technology

2017-06-01

information. Additionally, radio communications equipment were reevaluated in order to provide longer ranges, last longer on battery power, and be...every other device monitoring that radio frequency . Additionally, wireless signals are limited by distance, the construction materials in walls... communications , socio-psychological, and personality factors in the maintenance of crew coordination. Aviation, Space, and Environmental Medicine, 53( 11

Successful strategies for improving operating room efficiency at academic institutions.

PubMed

Overdyk, F J; Harvey, S C; Fishman, R L; Shippey, F

1998-04-01

In this prospective study, we evaluated the etiology of operating room (OR) delays in an academic institution, examined the impact of multidisciplinary strategies to improve OR efficiency, and established OR timing benchmarks for use in future OR efficiency studies. OR times and delay etiologies were collected for 94 cases during the initial phase of the study. Timing data and delay etiologies were analyzed, and 2 wk of multidisciplinary OR efficiency awareness education was conducted for the nursing, surgical, and anesthesia staff. After the education period, timing data were collected from 1787 cases, and monthly reports listing individual case delays and timing data were sent to the Chiefs of Service. For the first case of the day, patient in room, anesthesia ready, surgical preparation start, and procedure start time were significantly earlier (P < 0.01) in the posteducation period compared with the preeducation period, and the procedure start time for the first case of the day occurred, on average, 22 min earlier than all other procedures. For all cases combined, turnover time decreased, on average, by 16 min. Unavailability of surgeons, anesthesiologists, and residents decreased significantly (P < 0.05) as causes of OR delays. Anesthesia induction times were consistently longer for the vascular and cardiothoracic services, whereas surgical preparation time was increased for the neurosurgical and orthopedic services (P < 0.05). Identification of the etiology of OR inefficiency, combined with multidisciplinary awareness training and personal accountability, can improve OR efficiency. The time savings realized are probably most cost-effective when combined with more flexible OR staffing and improved OR scheduling. We achieved significant improvements in operating room efficiency by analyzing operating room data on causes of delays, devising strategies for minimizing the most common delays, and subsequently measuring delay data. Personal accountability, streamlining of procedures, interdisciplinary team work, and accurate data collection were all important contributors to improved efficiency.

The Impact of Trajectory Prediction Uncertainty on Air Traffic Controller Performance and Acceptability

NASA Technical Reports Server (NTRS)

Mercer, Joey S.; Bienert, Nancy; Gomez, Ashley; Hunt, Sarah; Kraut, Joshua; Martin, Lynne; Morey, Susan; Green, Steven M.; Prevot, Thomas; Wu, Minghong G.

2013-01-01

A Human-In-The-Loop air traffic control simulation investigated the impact of uncertainties in trajectory predictions on NextGen Trajectory-Based Operations concepts, seeking to understand when the automation would become unacceptable to controllers or when performance targets could no longer be met. Retired air traffic controllers staffed two en route transition sectors, delivering arrival traffic to the northwest corner-post of Atlanta approach control under time-based metering operations. Using trajectory-based decision-support tools, the participants worked the traffic under varying levels of wind forecast error and aircraft performance model error, impacting the ground automations ability to make accurate predictions. Results suggest that the controllers were able to maintain high levels of performance, despite even the highest levels of trajectory prediction errors.

[Comparative trial between traditional cesarean section and Misgav-Ladach technique].

PubMed

Gutiérrez, José Gabriel Tamayo; Coló, José Antonio Sereno; Arreola, María Sandra Huape

2008-02-01

The cesarean section was designed to extract to the neoborn, when the childbirth becomes difficult by the natural routes. The institutional obstetrical work demands long surgical time and high raw materials; therefore, simpler procedures must be implemented. To compare traditional cesarean section vs Misgav-Ladach technique to assess surgical time, and hospital stay and costs. Forty-eight pregnant patients at term with obstetrical indication for cesarean delivery were randomized in two groups: 24 were submitted to traditional cesarean and 24 to Misgav-Ladach technique. The outcomes included surgical time, bleeding, amount of sutures employed, pain intensity and some others adverse effects. The surgical time with Misgav-Ladach technique was shorter compared with traditional cesarean section, bleeding was consistently lesser and pain was also low. None adverse effects were registered in both groups. Although short follow-up showed significant operative time reduction and less bleeding, longer follow-up should be desirable in order to confirm no abdominal adhesions.

Human Life History Evolution Explains Dissociation between the Timing of Tooth Eruption and Peak Rates of Root Growth

PubMed Central

Dean, M. Christopher; Cole, Tim J.

2013-01-01

We explored the relationship between growth in tooth root length and the modern human extended period of childhood. Tooth roots provide support to counter chewing forces and so it is advantageous to grow roots quickly to allow teeth to erupt into function as early as possible. Growth in tooth root length occurs with a characteristic spurt or peak in rate sometime between tooth crown completion and root apex closure. Here we show that in Pan troglodytes the peak in root growth rate coincides with the period of time teeth are erupting into function. However, the timing of peak root velocity in modern humans occurs earlier than expected and coincides better with estimates for tooth eruption times in Homo erectus. With more time to grow longer roots prior to eruption and smaller teeth that now require less support at the time they come into function, the root growth spurt no longer confers any advantage in modern humans. We suggest that a prolonged life history schedule eventually neutralised this adaptation some time after the appearance of Homo erectus. The root spurt persists in modern humans as an intrinsic marker event that shows selection operated, not primarily on tooth tissue growth, but on the process of tooth eruption. This demonstrates the overarching influence of life history evolution on several aspects of dental development. These new insights into tooth root growth now provide an additional line of enquiry that may contribute to future studies of more recent life history and dietary adaptations within the genus Homo. PMID:23342167

Performing concurrent operations in academic vascular neurosurgery does not affect patient outcomes.

PubMed

Zygourakis, Corinna C; Lee, Janelle; Barba, Julio; Lobo, Errol; Lawton, Michael T

2017-11-01

OBJECTIVE Concurrent surgeries, also known as "running two rooms" or simultaneous/overlapping operations, have recently come under intense scrutiny. The goal of this study was to evaluate the operative time and outcomes of concurrent versus nonconcurrent vascular neurosurgical procedures. METHODS The authors retrospectively reviewed 1219 procedures performed by 1 vascular neurosurgeon from 2012 to 2015 at the University of California, San Francisco. Data were collected on patient age, sex, severity of illness, risk of mortality, American Society of Anesthesiologists (ASA) status, procedure type, admission type, insurance, transfer source, procedure time, presence of resident or fellow in operating room (OR), number of co-surgeons, estimated blood loss (EBL), concurrent vs nonconcurrent case, severe sepsis, acute respiratory failure, postoperative stroke causing neurological deficit, unplanned return to OR, 30-day mortality, and 30-day unplanned readmission. For aneurysm clipping cases, data were also obtained on intraoperative aneurysm rupture and postoperative residual aneurysm. Chi-square and t-tests were performed to compare concurrent versus nonconcurrent cases, and then mixed-effects models were created to adjust for different procedure types, patient demographics, and clinical indicators between the 2 groups. RESULTS There was a significant difference in procedure type for concurrent (n = 828) versus nonconcurrent (n = 391) cases. Concurrent cases were more likely to be routine/elective admissions (53% vs 35%, p < 0.001) and physician referrals (59% vs 38%, p < 0.001). This difference in patient/case type was also reflected in the lower severity of illness, risk of death, and ASA class in the concurrent versus nonconcurrent cases (p < 0.01). Concurrent cases had significantly longer procedural times (243 vs 213 minutes) and more unplanned 30-day readmissions (5.7% vs 3.1%), but shorter mean length of hospital stay (11.2 vs 13.7 days), higher rates of discharge to home (66% vs 51%), lower 30-day mortality rates (3.1% vs 6.1%), lower rates of acute respiratory failure (4.3% vs 8.2%), and decreased 30-day unplanned returns to the OR (3.3% vs 6.9%; all p < 0.05). Rates of severe sepsis, postoperative stroke, intraoperative aneurysm rupture, and postoperative aneurysm residual were equivalent between the concurrent and nonconcurrent groups (all p values nonsignificant). Mixed-effects models showed that after controlling for procedure type, patient demographics, and clinical indicators, there was no significant difference in acute respiratory failure, severe sepsis, 30-day readmission, postoperative stroke, EBL, length of stay, discharge status, or intraoperative aneurysm rupture between concurrent and nonconcurrent cases. Unplanned return to the OR and 30-day mortality were significantly lower in concurrent cases (odds ratio 0.55, 95% confidence interval 0.31-0.98, p = 0.0431, and odds ratio 0.81, p < 0.001, respectively), but concurrent cases had significantly longer procedure durations (odds ratio 21.73; p < 0.001). CONCLUSIONS Overall, there was a significant difference in the types of concurrent versus nonconcurrent cases, with more routine/elective cases for less sick patients scheduled in an overlapping fashion. After adjusting for patient demographics, procedure type, and clinical indicators, concurrent cases had longer procedure times, but equivalent patient outcomes, as compared with nonconcurrent vascular neurosurgical procedures.

Predictors for cecal insertion time: the impact of abdominal visceral fat measured by computed tomography.

PubMed

Nagata, Naoyoshi; Sakamoto, Kayo; Arai, Tomohiro; Niikura, Ryota; Shimbo, Takuro; Shinozaki, Masafumi; Noda, Mitsuhiko; Uemura, Naomi

2014-10-01

Several factors affect the risk for longer cecal insertion time. The aim of this study was to identify the predictors of longer insertion time and to evaluate the effect of visceral fat measured by CT. This is a retrospective observational study. Outpatients for colorectal cancer screening who underwent colonoscopies and CT were enrolled. Computed tomography was performed in individuals who requested cancer screening and in those with GI bleeding. Information on obesity indices (BMI, visceral adipose tissue, and subcutaneous adipose tissue area), constipation score, history of abdominal surgery, poor preparation, fellow involvement, diverticulosis, patient discomfort, and the amount of sedation used was collected. The cecal insertion rate was 95.2% (899/944), and 899 patients were analyzed. Multiple regression analysis showed that female sex, lower BMI, lower visceral adipose tissue area, lower subcutaneous adipose tissue area, higher constipation score, history of surgery, poor bowel preparation, and fellow involvement were independently associated with longer insertion time. When obesity indices were considered simultaneously, smaller subcutaneous adipose tissue area (p = 0.038), but not lower BMI (p = 0.802) or smaller visceral adipose tissue area (p = 0.856), was associated with longer insertion time; the other aforementioned factors remained associated with longer insertion time. In the subanalysis of normal-weight patients (BMI <25 kg/m), a smaller subcutaneous adipose tissue area (p = 0.002), but not a lower BMI (p = 0.782), was independently associated with a longer insertion time. Longer insertion time had a positive correlation with a higher patient discomfort score (ρ = 0.51, p < 0.001) and a greater amount of midazolam use (ρ = 0.32, p < 0.001). This single-center retrospective study includes a potential selection bias. In addition to BMI and intra-abdominal fat, female sex, constipation, history of abdominal surgery, poor preparation, and fellow involvement were predictors of longer cecal insertion time. Among the obesity indices, high subcutaneous fat accumulation was the best predictive factor for easier passage of the colonoscope, even when body weight was normal.

The CROES percutaneous nephrolithotomy global study: the influence of body mass index on outcome.

PubMed

Fuller, Andrew; Razvi, Hassan; Denstedt, John D; Nott, Linda; Pearle, Margaret; Cauda, Furio; Bolton, Damien; Celia, Antonio; de la Rosette, Jean

2012-07-01

In addition to more commonly forming stones, obese patients present a number of challenges when undergoing percutaneous nephrolithotomy. We evaluated percutaneous nephrolithotomy outcomes in 3,709 patients stratified by body mass index. A prospective database administered by CROES (Clinical Research Office of the Endourological Society) captured data on 5,803 patients treated with percutaneous nephrolithotomy between November 2007 and December 2009. Patients with known solitary kidney, previous percutaneous nephrolithotomy and congenital abnormalities were excluded from analysis. For statistical analysis patients were categorized as normal weight--body mass index 18.5 to 25 kg/m(2), overweight--25 to 30, obese--30 to 40 and super obese--greater than 40. During the study period 5,803 patients underwent percutaneous nephrolithotomy, of whom 3,709 met the inclusion criteria. As expected, obesity was associated with significantly higher rates of comorbid conditions and anticoagulant use (p < 0.001). Operative time was significantly longer in obese patients and use of a balloon device for tract dilation was more common (each p < 0.001). The stone-free rate decreased with obesity (p = 0.009), corresponding to a significantly higher re-treatment rate in this group (p < 0.001). No difference was seen in length of stay or the transfusion rate. No significant difference was seen in the overall complication rate among the 4 groups (p = 0.707). Percutaneous nephrolithotomy may be done safely in obese patients, although with a longer operative time, an inferior stone-free rate and a higher re-intervention rate. Copyright © 2012 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Treatment of hematomas after anterior cervical spine surgery: A retrospective study of 15 cases.

PubMed

Miao, Weiliang; Ma, Xiaojun; Liang, Deyong; Sun, Yu

2018-05-04

Postoperative hematoma is a rare and dangerous complication of cervical spine surgery. The aim of this study was to investigate the incidence and related factors of postoperative hematoma, and to report on 15 cases at our institution over a 6-year period. Fifteen cases of postoperative hematoma were retrospectively identified. We investigated their neurological outcomes, characteristics, and surgical data, and identified risk factors associated with postoperative (PO) hematoma. Patients with hematoma were compared to those with no hematoma, in order to identify risk factors. Retropharyngeal hematomas developed in seven cases and epidural hematomas in eight. The total incidence of postoperative hematoma was 1.2%: 0.5% retropharyngeal hematomas and 0.6% spinal epidural hematomas. At time of onset, the severity of paralysis was assessed as grade B in one case, grade C in six cases, and grade D in eight cases. Risk factors for PO hematoma were: (1) presence of ossification of the posterior longitudinal ligament (OPLL) (P<0.001); (2) longer operative duration (P=0.048); (3) greater number of surgical levels (P=0.02); and (4) higher body mass index (BMI; P=0.035). There was no significant difference in modified Japan Orthopedic Association scores between the hematoma group and non-hematoma group (P>0.05). Precise preoperative preparation and systematic evaluation are central to successful management of PO hematoma after anterior cervical surgery. Risk factors for PO hematoma include multilevel decompression, OPLL, higher BMI, and longer operation time. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

A Comparative Study of Outcomes for Endoscopic Diverticulotomy versus External Diverticulectomy

PubMed Central

Shahawy, Sarrah; Janisiewicz, Agnieszka M.; Annino, Don; Shapiro, Jo

2014-01-01

Objectives Current literature on the treatment of Zenker's Diverticulum (ZD) favors the use of various endoscopic procedures over external surgical techniques for patients, arguing that endoscopic approaches reduce intraoperative time and anesthesia, length of hospital stay, and days until oral diet is restarted. However, such techniques often have higher symptomatic recurrence rates and require further interventions. Because of our experience with both endoscopic diverticulotomy (ENDO) and external diverticulectomy (EXT) using the GIA-stapler, we sought to compare these two procedures in terms of in-hospital parameters, complications, return to normal diet, and rates of symptom recurrence. Study Design Case series with chart review. Setting Academic tertiary care hospital. Subjects Patients with Zenker's diverticulum who underwent surgical repair. Methods Retrospective analysis of 67 patients seen at Brigham and Women's Hospital between 1990 and 2012 with Zenker's diverticulum who underwent either an endoscopic Zenker's procedure (36) or an external stapler-assisted diverticulectomy with cricopharyngeal myotomy (31). Results Although the external stapler-assisted procedure for ZD does carry a longer intra-operative time and a slightly longer hospital stay than the endoscopic approach, it provides similar days until initiation of an oral diet and a similar incidence of post-operative complications. Further, it is superior to the endoscopic approach when one considers its much lower rate of symptomatic recurrence and need for revision procedures. Conclusion We argue that the external stapler-assisted diverticulectomy with cricopharyngeal myotomy should be considered as a viable treatment in patients who need definitive, single-session treatment for ZD, especially to prevent life-threatening aspiration pneumonia. PMID:24990870

LRO-LAMP failsafe door-open performance: improving FUV measurements of dayside lunar hydration

NASA Astrophysics Data System (ADS)

Davis, Michael W.; Greathouse, Thomas K.; Kaufmann, David E.; Retherford, Kurt D.; Versteeg, Maarten H.

2017-08-01

The Lunar Reconnaissance Orbiter's (LRO) Lyman Alpha Mapping Project (LAMP) is a lightweight (6.1 kg), lowpower (4.5 W), ultraviolet spectrograph based on the Alice instruments aboard the European Space Agency's Rosetta spacecraft and NASA's New Horizons spacecraft. Its primary job is to identify and localize exposed water frost in permanently shadowed regions (PSRs) near the Moon's poles, and to characterize landforms and albedos in PSRs. LRO launched on June 18, 2009 and reached lunar orbit four days later. LAMP operated with its failsafe door closed for its first seven years in flight. The failsafe door was opened in October 2016 to increase light throughput during dayside operations at the expense of no longer having the capacity to take further dark observations and slightly more operational complexity to avoid saturating the instrument. This one-time irreversible operation was approved after extensive review, and was conducted flawlessly. The increased throughput allows measurement of dayside hydration in one orbit, instead of averaging multiple orbits together to reach enough signal-to-noise. The new measurement mode allows greater time resolution of dayside water migration for improved investigations into the source and loss processes on the lunar surface. LAMP performance and optical characteristics after the failsafe door opening are described herein, including the new effective area, wavelength solution, and resolution.

Advanced Steels for Accident Tolerant Fuel Cladding in Current Light Water Reactors

NASA Astrophysics Data System (ADS)

Rebak, Raul B.

After the March 2011 Fukushima events, the U.S. Congress directed the Department of Energy (DOE) to focus efforts on the development of fuel cladding materials with enhanced accident tolerance. In comparison with the stand-ard UO2-Zirconium based system, the new fuels need to tolerate loss of active cooling in the core for a considerably longer time period while maintaining or improving the fuel performance during normal operation conditions. Advanced steels such as iron-chromium-aluminum (FeCrAl) alloys are being investigated for degradation behavior both under normal operation conditions in high temperature water (e.g. 288°C) and under accident conditions for reaction with steam up to 1400°C. Commercial and experimental alloys were tested for several periods of time in 100% superheated steam from 800°C to 1475°C. Results show that FeCrAl alloys significantly outperform the resistance in steam of the current zirconium alloys.

Transoral robotic surgery vs transoral laser microsurgery for resection of supraglottic cancer: a pilot surgery.

PubMed

Ansarin, Mohssen; Zorzi, Stefano; Massaro, Maria Angela; Tagliabue, Marta; Proh, Michele; Giugliano, Gioacchino; Calabrese, Luca; Chiesa, Fausto

2014-03-01

Transoral laser microsurgery (TLM) is a mature approach to supraglottic cancer, while transoral robotic surgery (TORS) is emerging. The present study compared these approaches. The first 10 patients (2002-2005) given TLM were compared with the first 10 (2007-2011) given TORS for cT1-3 cN0-cN2c supraglottic cancer. A feeding tube was used in four TLM and seven TORS patients. Margins were more often positive, but operating times shorter, in TORS. All 10 TORS patients are without evidence of disease, but only six TLM patients remain disease-free after much longer follow-up. TORS was considerably less uncomfortable and fatiguing for the surgeon. TORS seems as safe and effective as TLM. Shorter TORS operating times are probably attributable to prior experience with TLM. For laryngeal exposure, length of tube placement and margin evaluability, TLM was superior; however, this may change as TORS develops and transoral robotic instruments are optimized. Copyright © 2013 John Wiley & Sons, Ltd.

In vitro Comparison of Apical Debris Extrusion Using Rotary and Reciprocating Systems in Severely Curved Root Canals

PubMed Central

Delvarani, Abbas; Mohammadzadeh Akhlaghi, Nahid; Aminirad, Raana; Tour Savadkouhi, Sohrab; Vahdati, Seyed Aliakbar

2017-01-01

Introduction: The aim of this in vitro study was to compare the amount of apically extruded debris after root canal preparation using rotary and reciprocating systems in severely curved root canals. Methods and Materials: Thirty six extracted human mandibular first molars with 25-35° curvature in their mesiobuccal (MB) canal (according to Schneider’s method) were cleaned and shaped with ProTaper and WaveOne systems. The extruded debris was collected and their net weight was calculated. To compare the efficiency of the two systems, the operation time was also measured. The data were analyzed with t-test. Results: The amount of extruded debris in WaveOne group was significantly greater in comparison with ProTaper group (26%). The operating time for ProTaper was however, significantly longer than WaveOne. Conclusion: Both root preparation systems caused some degree of debris extrusion through the apical foramen. However, this amount was greater in WaveOne instruments. PMID:28179921

Space station propulsion requirements study

NASA Technical Reports Server (NTRS)

Wilkinson, C. L.; Brennan, S. M.

1985-01-01

Propulsion system requirements to support Low Earth Orbit (LEO) manned space station development and evolution over a wide range of potential capabilities and for a variety of STS servicing and space station operating strategies are described. The term space station and the overall space station configuration refers, for the purpose of this report, to a group of potential LEO spacecraft that support the overall space station mission. The group consisted of the central space station at 28.5 deg or 90 deg inclinations, unmanned free-flying spacecraft that are both tethered and untethered, a short-range servicing vehicle, and a longer range servicing vehicle capable of GEO payload transfer. The time phasing for preferred propulsion technology approaches is also investigated, as well as the high-leverage, state-of-the-art advancements needed, and the qualitative and quantitative benefits of these advancements on STS/space station operations. The time frame of propulsion technologies applicable to this study is the early 1990's to approximately the year 2000.

Perioperative and acute care outcomes in morbidly obese patients with acetabular fractures at a Level 1 trauma center

PubMed Central

Vincent, Heather K.; Haupt, Edward; Tang, Sonya; Egwuatu, Adaeze; Vlasak, Richard; Horodyski, MaryBeth; Carden, Donna; Sadisivan, Kalia K.

2014-01-01

Background Controversy exists regarding obesity-related injury severity and clinical outcomes after orthopedic trauma. Purpose The purposes of this study were to expand our understanding of the effect of morbid obesity on perioperative and acute care outcomes after acetabular fracture. Methods This was a retrospective review of patients with acetabular fracture after trauma. Non-morbidly obese (BMI < 35 kg/m2) and morbidly obese (BMI ≥ 35 kg/m2; N = 81). Injury severity scores and Glasgow Coma Scale scores (GCS) were collected. Perioperative and acute care outcomes were positioning and operative time, extra fractures, estimated blood loss, complications, hospital charges, ventilator days, transfusions, length of stay (LOS) and discharge destination. Positioning and operative times were longer in morbidly obese patients (p < 0.05). No other differences existed between groups. Conclusions Orthopedic trauma surgeons and care teams can expect similar acute care outcomes in morbidly obese and non-morbidly obese patients with acetabular fracture. PMID:25104886

Optimation of Operation System Integration between Main and Feeder Public Transport (Case Study: Trans Jakarta-Kopaja Bus Services)

NASA Astrophysics Data System (ADS)

Miharja, M.; Priadi, Y. N.

2018-05-01

Promoting a better public transport is a key strategy to cope with urban transport problems which are mostly caused by a huge private vehicle usage. A better public transport service quality not only focuses on one type of public transport mode, but also concerns on inter modes service integration. Fragmented inter mode public transport service leads to a longer trip chain as well as average travel time which would result in its failure to compete with a private vehicle. This paper examines the optimation process of operation system integration between Trans Jakarta Bus as the main public transport mode and Kopaja Bus as feeder public transport service in Jakarta. Using scoring-interview method combined with standard parameters in operation system integration, this paper identifies the key factors that determine the success of the two public transport operation system integrations. The study found that some key integration parameters, such as the cancellation of “system setoran”, passenger get in-get out at official stop points, and systematic payment, positively contribute to a better service integration. However, some parameters such as fine system, time and changing point reliability, and information system reliability are among those which need improvement. These findings are very useful for the authority to set the right strategy to improve operation system integration between Trans Jakarta and Kopaja Bus services.

Loop ileostomy closure: comparison of cost effectiveness between suture and stapler.

PubMed

Horisberger, Karoline; Beldi, Guido; Candinas, Daniel

2010-12-01

Closure of loop ileostomy can be safely performed using sutures or staplers. The aim of the present study was to compare the cost effectiveness of three different techniques. A total of 128 consecutive patients who underwent closure of loop ileostomy between January 2002 and December 2008 were analyzed retrospectively. The primary outcome parameter was operative cost. Closure of ileostomy was performed in 66 patients with hand-sewn anastomosis, in 25 patients with stapler only, and in 37 patients with a combination of stapler and suture. There were no differences in terms of early and late postoperative complications. Operative time was significantly longer for "suture only" (101.4 ± 26 min) than for "stapler/suture" (-4.9 min) and "stapler only" (-17.8 min); the difference between the three groups is significant (p = 0.05). Duration of hospital stay was not different among the three groups. Operative costs with "stapler/suture" (1,755.9 ± 355.6 EUR) were significantly higher than with "suture only" (-254 EUR; p = 0.001) and "stapler only" (-236 EUR; p = 0.005). Operative time using the stapler only is significantly shorter than with hand-sewn anastomosis or combinations of stapler and suture. Operative costs are significantly higher for a procedure that includes suture and stapler.

40 CFR 61.222 - Standard.

Code of Federal Regulations, 2010 CFR

2010-07-01

... uranium mill tailings pile that are no longer operational shall not exceed 20 pCi/(m2-sec) (1.9 pCi/(ft2-sec)) of radon-222. (b) Once a uranium mill tailings pile or impoundment ceases to be operational it...

Evaluation of the efficacy of laparoscopic resection for the management of exogenous cesarean scar pregnancy.

PubMed

Wang, Guangwei; Liu, Xiaofei; Bi, Fangfang; Yin, Lili; Sa, Rina; Wang, Dandan; Yang, Qing

2014-05-01

To retrospectively analyze the clinical data of 71 patients with exogenous cesarean scar pregnancy (CSP) treated in our hospital in the past 2 years, to compare the outcomes of exogenous CSP treated with different methods, and to evaluate the safety and feasibility of laparoscopic resection of exogenous CSP. Comparative observational study. Tertiary medical centers. 71 women with exogenous cesarean scar pregnancy. Hysteroscopic resection of CSP, and laparoscopic resection of CSP. Operation time, intraoperative blood loss, postoperative drainage of the uterine cavity, postoperative days in hospital, time for β-human chorionic gonadotropin (β-hCG) to return to normal levels, absorption time of the mass. For the laparoscopic group, the time for serum β-hCG to return normal levels and the postoperative drainage of the uterine cavity were significantly lower than in the patients who had undergone hysteroscopic resection. We found no statistically significant difference in the intraoperative blood loss and postoperative days in hospital between the two groups, but the operation time was longer in laparoscopic group. Laparoscopic surgery for a cesarean scar pregnancy has the advantages of a high success rate, fewer complications, and a shorter time for β-hCG levels to normalize. This procedure is especially suitable for the treatment of exogenous CSP. Copyright © 2014. Published by Elsevier Inc.

A minimization principle for the description of modes associated with finite-time instabilities

PubMed Central

Babaee, H.

2016-01-01

We introduce a minimization formulation for the determination of a finite-dimensional, time-dependent, orthonormal basis that captures directions of the phase space associated with transient instabilities. While these instabilities have finite lifetime, they can play a crucial role either by altering the system dynamics through the activation of other instabilities or by creating sudden nonlinear energy transfers that lead to extreme responses. However, their essentially transient character makes their description a particularly challenging task. We develop a minimization framework that focuses on the optimal approximation of the system dynamics in the neighbourhood of the system state. This minimization formulation results in differential equations that evolve a time-dependent basis so that it optimally approximates the most unstable directions. We demonstrate the capability of the method for two families of problems: (i) linear systems, including the advection–diffusion operator in a strongly non-normal regime as well as the Orr–Sommerfeld/Squire operator, and (ii) nonlinear problems, including a low-dimensional system with transient instabilities and the vertical jet in cross-flow. We demonstrate that the time-dependent subspace captures the strongly transient non-normal energy growth (in the short-time regime), while for longer times the modes capture the expected asymptotic behaviour. PMID:27118900

Use of an intuitive telemanipulator system for remote trauma surgery: an experimental study.

PubMed

Bowersox, J C; Cordts, P R; LaPorta, A J

1998-06-01

Death from battlefield trauma occurs rapidly. Potentially salvageable casualties generally exsanguinate from truncal hemorrhage before operative intervention is possible. An intuitive telemanipulator system that would allow distant surgeons to remotely treat injured patients could improve the outcome from severe injuries. We evaluated a prototype, four-degree-of-freedom, telesurgery system that provides a surgeon with a stereoscopic video display of a remote operative field. Using dexterous robotic manipulators, surgical instruments at the remote site can be precisely controlled, enabling operative procedures to be performed remotely. Surgeons (n = 3) used the telesurgery system to perform organ excision, hemorrhage control, suturing, and knot tying on anesthetized swine. The ability to complete tasks, times required, technical quality, and subjective impressions were recorded. Surgeons using the telesurgery system were able to close gastrotomies remotely, although times required were 2.7 times as long as those performed by conventional techniques (451 +/- 83 versus 1,235 +/- 165 seconds, p < 0.002). Cholecystectomies, hemorrhage control from liver lacerations, and enterotomy closures were successfully completed in all attempts. Force feedback and stereoscopic video display were important for achieving intuitive performance with the telesurgery system, although tasks were completed adequately in the absence of these sensory cues. We demonstrated the feasibility of performing standard surgical procedures remotely, with the operating surgeon linked to the distant field only by electronic cabling. Complex manipulations were possible, although the times required were much longer. The capabilities of the system used would not support resuscitative surgery. Telesurgery is unlikely to play a role in early trauma management, but may be a unique research tool for acquiring basic knowledge of operative surgery.

Water Management Applications of Advanced Precipitation Products

NASA Astrophysics Data System (ADS)

Johnson, L. E.; Braswell, G.; Delaney, C.

2012-12-01

Advanced precipitation sensors and numerical models track storms as they occur and forecast the likelihood of heavy rain for time frames ranging from 1 to 8 hours, 1 day, and extended outlooks out to 3 to 7 days. Forecast skill decreases at the extended time frames but the outlooks have been shown to provide "situational awareness" which aids in preparation for flood mitigation and water supply operations. In California the California-Nevada River Forecast Centers and local Weather Forecast Offices provide precipitation products that are widely used to support water management and flood response activities of various kinds. The Hydrometeorology Testbed (HMT) program is being conducted to help advance the science of precipitation tracking and forecasting in support of the NWS. HMT high-resolution products have found applications for other non-federal water management activities as well. This presentation will describe water management applications of HMT advanced precipitation products, and characterization of benefits expected to accrue. Two case examples will be highlighted, 1) reservoir operations for flood control and water supply, and 2) urban stormwater management. Application of advanced precipitation products in support of reservoir operations is a focus of the Sonoma County Water Agency. Examples include: a) interfacing the high-resolution QPE products with a distributed hydrologic model for the Russian-Napa watersheds, b) providing early warning of in-coming storms for flood preparedness and water supply storage operations. For the stormwater case, San Francisco wastewater engineers are developing a plan to deploy high resolution gap-filling radars looking off shore to obtain longer lead times on approaching storms. A 4 to 8 hour lead time would provide opportunity to optimize stormwater capture and treatment operations, and minimize combined sewer overflows into the Bay.ussian River distributed hydrologic model.

Increasing time to postoperative stereotactic radiation therapy for patients with resected brain metastases: investigating clinical outcomes and identifying predictors associated with time to initiation.

PubMed

Yusuf, Mehran B; Amsbaugh, Mark J; Burton, Eric; Nelson, Megan; Williams, Brian; Koutourousiou, Maria; Nauta, Haring; Woo, Shiao

2018-02-01

We sought to determine the impact of time to initiation (TTI) of post-operative radiosurgery on clinical outcomes for patients with resected brain metastases and to identify predictors associated with TTI. All patients with resected brain metastases treated with postoperative SRS or fractionated stereotactic radiation therapy (fSRT) from 2012 to 2016 at a single institution were reviewed. TTI was defined as the interval from resection to first day of radiosurgery. Receiver operating characteristic (ROC) curves were used to identify an optimal threshold for TTI with respect to local failure (LF). Survival outcomes were estimated using the Kaplan-Meier method and analyzed using the log-rank test and Cox proportional hazards models. Logistic regression models were used to identify factors associated with ROC-determined TTI covariates. A total of 79 resected lesions from 73 patients were evaluated. An ROC curve of LF and TTI identified an optimal threshold for TTI of 30.5 days, with an area under the curve of 0.637. TTI > 30 days was associated with an increased hazard of LF (HR 4.525, CI 1.239-16.527) but was not significantly associated with survival (HR 1.002, CI 0.547-1.823) or distant brain failure (DBF, HR 1.943, CI 0.989-3.816). Fifteen patients (20.5%) required post-operative inpatient rehabilitation. Post-operative rehabilitation was associated with TTI > 30 days (OR 1.48, CI 1.142-1.922). In our study of resected brain metastases, longer time to initiation of post-operative radiosurgery was associated with increased local failure. Ideally, post-op SRS should be initiated within 30 days of resection if feasible.

30 CFR 773.23 - Suspension or rescission requirements for improvidently issued permits.

Code of Federal Regulations, 2010 CFR

2010-07-01

... improvidently issued permits. 773.23 Section 773.23 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR SURFACE COAL MINING AND RECLAMATION OPERATIONS PERMITS AND COAL... jurisdiction over the violation; (2) You or your operator no longer own or control the relevant operation; (3...

47 CFR 15.37 - Transition provisions for compliance with the rules.

Code of Federal Regulations, 2010 CFR

2010-10-01

...) Prior to May 25, 1991, person shall import, market or operate intentional radiators within the band 902... operation within the band 902-905 MHz. (e) For cordless telephones: The manufacture and importation of... approval may no longer be obtained for medical telemetry equipment operating under the provisions of § 15...

Left atriotomy versus right atriotomy trans-septal approach for left atrial myxoma.

PubMed

Hatemi, A C; Gürsoy, M; Tongut, A; Kiliçkesmez, K; Karaoğlu, K; Küçükoğlu, S; Kansiz, E

2010-01-01

The biatrial approach has been the classic means of access for left atrial myxoma resection. Increased surgical experience led cardiac surgeons to favour the uniatrial approach to reduce incisions and achieve adequate exposure. In this study, two unilateral surgical approaches were compared in 18 consecutive left atrial myxoma cases. Patients were divided into two groups according to the surgical approach: left atriotomy (group 1, n = 9) and right atriotomy trans-septal approach (group 2, n = 9). Comparison criteria included pre- and post-operative functional capacity, cardiac rhythm, left ventricular ejection fraction, pulmonary artery pressure, left atrial dimensions, cardiopulmonary bypass time, aortic cross-clamp time, drainage over 48 h post-operatively, units of blood transfused, extubation time and length of stay in the intensive care unit and hospital. No significant between-group difference was observed in any criteria except aortic cross-clamp time, which was significantly longer in group 2 than in group 1. No recurrence of myxoma occurred in either group for the 15 patients followed up. Right atrial trans-septal incision appears to be as safe and effective as the left atriotomy approach for left atrial myxoma resection.

Laparoscopic versus open repair of para-umbilical hernia. Is it a good alternative?

PubMed

Malik, Arshad Mehmood

2015-08-01

To compare the experience of laparoscopic repair of para-umbilical hernia with conventional open repair in terms of operative time, pre- and post-operative complications, total hospital stay, post-operative pain, morbidity, mortality and cosmesis. The prospective, randomized study was conducted at Liaquat University of Medical and Health Sciences, Jamshoro, Pakistan, and two private hospitals from June 2011 to June 2013, and comprised patients who were admitted with para-umbilical hernias of different sizes during the study period. The patients were divided into two groups. Group A underwent laparoscopic surgery, while Group B had conventional mesh repair. Variables studied included duration of surgery, operative and post-operative complications, morbidity and mortality. SPSS 20 was used for statistical analysis. Of the 337 patients in the study, 200(59.34%) were at the Liaquat University Hospital, while remaining 137(40.65%) patients were operated in two private hospitals. The overall mean age of the study sample was 42.18±9.789 years (range: 23-73). There were 68(20.18%) males and 269(79.82%) females. There were 166(49.26%) patients in Group A and 171(50.74%) Group B. The operative time was comparatively longer in Group A (p<0.001) especially in the first 30 operations. The laparoscopic approach was associated with a comparatively low incidence of operative and post-operative complications, reduced duration of hospital stay and cosmetically better results (p<0.05). There was no mortality in this series. Laparoscopic para-umbilical hernia repair, though a new technique, gave promising results compared to open conventional technique. However, there is a long way to go before coming to a consensus.

Flight Deck Surface Trajectory-based Operations (STBO): Results of Piloted Simulations and Implications for Concepts of Operation (ConOps)

NASA Technical Reports Server (NTRS)

Foyle, David C.; Hooey, Becky L.; Bakowski, Deborah L.

2013-01-01

The results offour piloted medium-fidelity simulations investigating flight deck surface trajectory-based operations (STBO) will be reviewed. In these flight deck STBO simulations, commercial transport pilots were given taxi clearances with time and/or speed components and required to taxi to the departing runway or an intermediate traffic intersection. Under a variety of concept of operations (ConOps) and flight deck information conditions, pilots' ability to taxi in compliance with the required time of arrival (RTA) at the designated airport location was measured. ConOps and flight deck information conditions explored included: Availability of taxi clearance speed and elapsed time information; Intermediate RTAs at intermediate time constraint points (e.g., intersection traffic flow points); STBO taxi clearances via ATC voice speed commands or datal ink; and, Availability of flight deck display algorithms to reduce STBO RTA error. Flight Deck Implications. Pilot RTA conformance for STBO clearances, in the form of ATC taxi clearances with associated speed requirements, was found to be relatively poor, unless the pilot is required to follow a precise speed and acceleration/deceleration profile. However, following such a precise speed profile results in inordinate head-down tracking of current ground speed, leading to potentially unsafe operations. Mitigating these results, and providing good taxi RTA performance without the associated safety issues, is a flight deck avionics or electronic flight bag (EFB) solution. Such a solution enables pilots to meet the taxi route RTA without moment-by-moment tracking of ground speed. An avionics or EFB "error-nulling" algorithm allows the pilot to view the STBO information when the pilot determines it is necessary and when workload alloys, thus enabling the pilot to spread his/her attention appropriately and strategically on aircraft separation airport navigation, and the many other flight deck tasks concurrently required. Surface Traffic Management (STM) System Implications. The data indicate a number of implications regarding specific parameters for ATC/STM algorithm development. Pilots have a tendency to arrive at RTA points early with slow required speeds, on time for moderate speeds, and late with faster required speeds. This implies that ATC/STM algorithms should operate with middle-range speeds, similar to that of non-STBO taxi performance. Route length has a related effect: Long taxi routes increase the earliness with slow speeds and the lateness with faster speeds. This is likely due to the" open-loop" nature of the task in which the speed error compounds over a longer time with longer routes. Results showed that this may be mitigated by imposing a small number oftime constraint points each with their own RTAs effectively tuming a long route into a series of shorter routes - and thus improving RTA performance. STBO ConOps Implications. Most important is the impact that these data have for NextGen STM system ConOps development. The results of these experiments imply that it is not reasonable to expect pilots to taxi under a "Full STBO" ConOps in which pilots are expected to be at a predictable (x,y) airport location for every time (t). An STBO ConOps with a small number of intermediate time constraint points and the departing runway, however, is feasible, but only with flight deck equipage enabling the use of a display similar to the "error-nulling algorithm/display" tested.

Stability and safety of MA50 intraocular lens placed in the sulcus.

PubMed

Kemp, P S; Oetting, T A

2015-11-01

To describe the safety and stability of sulcus placement of the MA50 intraocular lens (IOL). Consecutive patients with MA50 IOLs placed in the sulcus at the University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA, from 1997 to 2012 were identified. Inclusion criteria included patients with over 4 weeks of follow-up data. AEL was compared with incidence of IOL decentration using at two-tailed Student's t-test. Fifty eyes of 49 patients meeting the inclusion criteria were identified. Four weeks post-operatively, the average best-corrected visual acuity was 20/30. IOL decentration occurred in 14% of patients; patients with decentered IOLs had a significantly longer average AEL (25.37 mm) than patients whose IOL remained centered (23.94 mm, P=0.017). Other complications included uveitis-glaucoma-hyphema syndrome (12%), iritis (8%), and glaucoma (6%). There were no cases of pigment dispersion syndrome or need for lens exchange. Twelve eyes (24%) had intra-operative optic capture by the anterior capsule, none of which had post-operative decentration. The MA50 IOL is a reasonable, stable option for placement in the sulcus, with a low-risk profile; however, in eyes with longer AEL and presumably larger anterior segment, surgeons should consider placing an IOL with longer haptic distance than the MA50 to maintain centration. Optic capture of the MA50 IOL by the anterior capsule should be considered for longer eyes, as it is protective against decentration.

[Effect of dexmedetomidine on emergence agitation after general anesthesia in children undergoing odontotherapy in day-surgery operating room].

PubMed

Lin, Luo; Yueming, Zhang; Meisheng, Li; Jiexue, Wang; Yang, Ji

2017-12-01

To study the effectiveness of dexmedetomidine used for general anesthesia maintenance in children undergoing odontotherapy in day-surgery operating room in reducing the incidence of emergence agitation (EA). Eighty children undergoing odontotherapy and under general anesthesia in day-surgery operating room were randomized into two groups, group A (n=40) and group B (n=40). Each patient in group A was administered with a bolus dose of dexmedetomidine (1.0 μg·kg⁻¹, saline diluted to 10 mL) pump-infused after intubation and a maintenance dose of 0.1-0.4 mL·(kg·h)⁻¹ followed-up until 45 min before the end of operation. Each patient in group B was administered with a bolus dose of normal saline 10 mL pump-infused after intubation and maintenance dose of 0.1-0.4 mL·(kg·h)⁻¹ followed-up until 45 min before the end of operation. Gender, age, weight, physical status according to the American Society of Anesthesiologists, perioperative heart rate (HR), mean arterial pressure (MAP), pulse oxygen saturation (SpO₂), sufentanil dosage, duration of surgery, time of extubation, time of regaining consciousness, and time to reach modified Aldrete's score≥12 were recorded. Behavior in postanesthesia care unit was rated on the four-point agitation scale. Compared with group B, decreases were observed in HR and MAP at the beginning of operation, in 10 and 30 min, 1 and 2 h after the beginning of operation, and after extubation of group A (P<0.05). Sufentanil dosage and incidence of EA during recovery of group A were also lower than those of group B (P<0.05). Time to regain consciousness and time to reach modified Aldrete's score≥12 of group A were longer than those of group B (P<0.05). No statistical difference was observed between other indexes of the two groups. As an anesthetic used for general anesthesia maintenance in children undergoing odontotherapy in day-surgery operating room, dexmedetomidine results in low incidence of EA during recovery and more stable vital signs.

Feasibility and Learning Curve of Robotic Laparoendoscopic Single-Site Surgery in Gynecology.

PubMed

Buckley de Meritens, Alexandre; Kim, Julia; Dinkelspiel, Helen; Chapman-Davis, Eloise; Caputo, Thomas; Holcomb, Kevin M

2017-02-01

Single-site laparoscopy has proven to be a desirable option for patients undergoing gynecologic surgery, with some studies indicating improved cosmesis and less perioperative pain compared with standard approaches. This study describes the safety and feasibility of a novel robotic laparoendoscopic single-site surgery (R-LESS) platform as it is incorporated into a surgeon's practice with extensive multiport robotic surgical experience but limited LESS experience. We reviewed 83 women undergoing R-LESS by a single surgeon from September 2013 through August 2015. Operative times (total operative time, console time, docking time) were collected prospectively for the first 53 cases, and total operative time was collected retrospectively for the next 30 cases. Clinical parameters, including age, estimated blood loss, body mass index (BMI), prior abdominal surgeries, conversion to laparotomy, procedure type, uterine weight, length of hospital stay, and complications, were retrospectively collected from medical charts. Eighty-two of 83 surgeries were completed successfully with a single incision. One surgery was converted to multiport robotics for para-aortic lymph node dissection. Twelve surgeries were performed for cancer (ovary 1, uterus 8, and cervix 3). Eight patients underwent pelvic lymph node biopsy. The median total operative time for hysterectomies was 128 minutes (range, 60-275). After the first 13 hysterectomies the total operative time and the console time decreased significantly from 165.3 to 131.1 minutes (p = .032) and from 84.9 to 57.1 minutes (p = .028), respectively. Mean docking time halved from 7.8 minutes to 3.4 minutes comparing the first 10 cases to the last 10 cases. Surgical times were longer with larger BMIs, but the console time decreased with experience regardless of BMI. The mean uterine weight was 164 g (range, 30-460). Complications included 2 umbilical hernias (2.4%) and 1 conversion to multiport. In conclusion, R-LESS is a feasible and safe surgical platform for gynecologic procedures. A small number of cases are needed to significantly improve operative times when it is introduced on a surgeon's practice with limited experience in LESS but familiar with robotic surgery. Further study is needed to investigate the cost, benefits, and long-term outcomes of R-LESS. Published by Elsevier Inc.

Concept of Operations Evaluation for Using Remote-Guidance Ultrasound for Exploration Spaceflight.

PubMed

Hurst, Victor W; Peterson, Sean; Garcia, Kathleen; Ebert, Douglas; Ham, David; Amponsah, David; Dulchavsky, Scott

2015-12-01

Remote-guidance (RG) techniques aboard the International Space Station (ISS) have enabled astronauts to collect diagnostic-level ultrasound (US) images. Exploration-class missions will likely require nonformally trained sonographers to operate with greater autonomy given longer communication delays (> 6 s for missions beyond the Moon) and blackouts. Training requirements for autonomous collection of US images by non-US experts are being determined. Novice US operators were randomly assigned to one of three groups to collect standardized US images while drawing expertise from A) RG only, B) a computer training tool only, or C) both RG and a computer training tool. Images were assessed for quality and examination duration. All operators were given a 10-min standardized generic training session in US scanning. The imaging task included: 1) bone fracture assessment in a phantom and 2) Focused Assessment with Sonography in Trauma (FAST) examination in a healthy volunteer. A human factors questionnaire was also completed. Mean time for group B during FAST was shorter (20.4 vs. 22.7 min) than time for the other groups. Image quality scoring was lower than in groups A or C, but all groups produced images of acceptable diagnostic quality. RG produces US images of higher quality than those produced with only computer-based instruction. Extended communication delays in exploration missions will eliminate the option of real-time guidance, thus requiring autonomous operation. The computer program used appears effective and could be a model for future digital US expertise banks. Terrestrially, it also provides adequate self-training and mentoring mechanisms.

Transtracheal single-point stent fixation in posttracheotomy tracheomalacia under cone-beam computer tomography guidance by transmural suturing with the Berci needle - a perspective on a new tool to avoid stent migration of Dumon stents.

PubMed

Hohenforst-Schmidt, Wolfgang; Linsmeier, Bernd; Zarogoulidis, Paul; Freitag, Lutz; Darwiche, Kaid; Browning, Robert; Turner, J Francis; Huang, Haidong; Li, Qiang; Vogl, Thomas; Zarogoulidis, Konstantinos; Brachmann, Johannes; Rittger, Harald

2015-01-01

Tracheomalacia or tracheobronchomalacia (TM or TBM) is a common problem especially for elderly patients often unfit for surgical techniques. Several surgical or minimally invasive techniques have already been described. Stenting is one option but in general long-time stenting is accompanied by a high complication rate. Stent removal is more difficult in case of self-expandable nitinol stents or metallic stents in general in comparison to silicone stents. The main disadvantage of silicone stents in comparison to uncovered metallic stents is migration and plugging. We compared the operation time and in particular the duration of a sufficient Dumon stent fixation with different techniques in a patient with severe posttracheotomy TM and strongly reduced mobility of the vocal cords due to Parkinson's disease. The combined approach with simultaneous Dumon stenting and endoluminal transtracheal externalized suture under cone-beam computer tomography guidance with the Berci needle was by far the fastest approach compared to a (not performed) surgical intervention, or even purely endoluminal suturing through the rigid bronchoscope. The duration of the endoluminal transtracheal externalized suture was between 5 minutes and 9 minutes with the Berci needle; the pure endoluminal approach needed 51 minutes. The alternative of tracheobronchoplasty was refused by the patient. In general, 180 minutes for this surgical approach is calculated. The costs of the different approaches are supposed to vary widely due to the fact that in Germany 1 minute in an operation room costs on average approximately 50-60€ inclusive of taxes. In our own hospital (tertiary level), it is nearly 30€ per minute in an operation room for a surgical approach. Calculating an additional 15 minutes for patient preparation and transfer to wake-up room, therefore a total duration inside the investigation room of 30 minutes, the cost per flexible bronchoscopy is per minute on average less than 6€. Although the Dumon stenting requires a set-up with more expensive anesthesiology accompaniment, which takes longer than a flexible investigation estimated at 1 hour in an operation room, still without calculation of the costs of the materials and specialized staff that the surgical approach would consume at least 3,000€ more than a minimally invasive approach performed with the Berci needle. This difference is due to the longer time of the surgical intervention which is calculated at approximately 180 minutes in comparison to the achieved non-surgical approach of 60 minutes in the operation suite.

Transvaginal cholecystectomy versus single-incision laparoscopic cholecystectomy versus four-port laparoscopic cholecystectomy: a prospective cohort study.

PubMed

Solomon, Daniel; Shariff, Amir H; Silasi, Dan-Arin; Duffy, Andrew J; Bell, Robert L; Roberts, Kurt E

2012-10-01

This report describes the first prospective cohort study comparing transvaginal cholecystectomies (TVC) with single incision laparoscopic cholecystectomies (SILC) and four-port laparoscopic cholecystectomies (4PLC). Between May 2009 and August 2010, 14 patients underwent a TVC. These patients were compared with patients who underwent SILC (22 patients) or 4PLC (11 patients) in a concurrent, randomized, controlled trial. Demographic data, operative time, numerical pain scales, complications, and return to work were recorded. Mean age (TVC: 33.5 ± 3.0 year; SILC: 38.4 ± 3.3 year; 4PLC: 35.5 ± 4.1 year; p = 0.58) and mean BMI (TVC: 28.8 ± 1.5 kg/m(2); SILC: 31.8 ± 1 kg/m(2); 4PLC: 31.4 ± 2.2 kg/m(2); p = 0.35) were not statistically significant. However, mean operative time (TVC: 67 ± 3.9 min; SILC: 48.9 ± 2.6 min; 4PLC: 42.3 ± 3.9 min; p < 0.001) was significantly longer for TVC. Numerical pain scales showed significantly lower pain scores on POD 1 and 3 for TVC compared with SILC and 4PLC (TVC: 4.1 ± 0.5 and 2.9 ± 0.7; SILC: 6.1 ± 0.5 and 5.3 ± 0.5; 4PLC: 5.7 ± 0.4 and 4.7 ± 0.3; p = 0.02) with equilibration of pain scores by days 14 and 30. Return to work (TVC: 6.4 ± 1.5 days; SILC: 13.1 ± 1.3 days; 4PLC: 14.1 ± 1.4 days; p < 0.001) also was significantly faster for patients in the TVC group. One conversion in the TVC group to a 4PLC was necessary due to adhesions within the pelvis. One dislodged IUD was seen and immediately replaced in the TVC group. One hernia was observed in the SILC group. Transvaginal cholecystectomy is a safe and well-tolerated procedure with statistically significantly less pain at 1 and 3 days after surgery, with a faster return to work but longer operative times compared with single incision and four-port laparoscopic cholecystectomy.

NASA Global Hawk: Project Overview and Future Plans

NASA Technical Reports Server (NTRS)

Naftel, J. Chris

2011-01-01

The National Aeronautics and Space Administration (NASA) Global Hawk Project became operational in 2009 and began support of Earth science in 2010. Thus far, the NASA Global Hawk has completed three Earth science campaigns and preparations are under way for two extensive multi-year campaigns. One of the most desired performance capabilities of the Global Hawk aircraft is very long endurance: the Global Hawk aircraft can remain airborne longer than almost all other jet-powered aircraft currently flying, and longer than all other aircraft available for airborne science use. This paper describes the NASA Global Hawk system, payload accommodations, concept of operations, and the scientific data-gathering campaigns.

Predictive factors for postoperative visual function of primary chronic rhegmatogenous retinal detachment after scleral buckling.

PubMed

Fang, Wei; Li, Jiu-Ke; Jin, Xiao-Hong; Dai, Yuan-Min; Li, Yu-Min

2016-01-01

To evaluate predictive factors for postoperative visual function of primary chronic rhegmatgenous retinal detachment (RRD) after sclera buckling (SB). Totally 48 patients (51 eyes) with primary chronic RRD were included in this prospective interventional clinical cases study, which underwent SB alone from June 2008 to December 2014. Age, sex, symptoms duration, detached extension, retinal hole position, size, type, fovea on/off, proliferative vitreoretinopathy (PVR), posterior vitreous detachment (PVD), baseline best corrected visual acuity (BCVA), operative duration, follow up duration, final BCVA were measured. Pearson correlation analysis, Spearman correlation analysis and multivariate linear stepwise regression were used to confirm predictive factors for better final visual acuity. Student's t-test, Wilcoxon two-sample test, Chi-square test and logistic stepwise regression were used to confirm predictive factors for better vision improvement. Baseline BCVA was 0.8313±0.6911 logMAR and final BCVA was 0.4761±0.4956 logMAR. Primary surgical success rate was 92.16% (47/51). Correlation analyses revealed shorter symptoms duration (r=0.3850, P=0.0053), less detached area (r=0.5489, P<0.0001), fovea (r=0.4605, P=0.0007), no PVR (r=0.3138, P=0.0250), better baseline BCVA (r=0.7291, P<0.0001), shorter operative duration (r=0.3233, P=0.0207) and longer follow up (r=-0.3358, P=0.0160) were related with better final BCVA, while independent predictive factors were better baseline BCVA [partial R-square (PR(2))=0.5316, P<0.0001], shorter symptoms duration (PR(2)=0.0609, P=0.0101), longer follow up duration (PR(2)=0.0278, P=0.0477) and shorter operative duration (PR(2)=0.0338, P=0.0350). Patients with vision improvement took up 49.02% (25/51). Univariate and multivariate analyses both revealed predictive factors for better vision improvement were better baseline vision [odds ratio (OR) =50.369, P=0.0041] and longer follow up duration (OR=1.144, P=0.0067). Independent predictive factors for better visual outcome of primary chronic RRD after SB are better baseline BCVA, shorter symptoms duration, shorter operative duration and longer follow up duration, while independent predictive factors for better vision improvement after operation are better baseline vision and longer follow up duration.

Fluidity in the Networked Society--Self-Initiated learning as a Digital Literacy Competence

ERIC Educational Resources Information Center

Levinsen, Karin Tweddell

2011-01-01

In the globalized economies e-permeation has become a basic condition in our everyday lives. ICT can no longer be understood solely as artefacts and tools and computer-related literacy are no longer restricted to the ability to operate digital tools for specific purposes. The network society, and therefore also eLearning are characterized by…

Benefits of xiphoidectomy in total gastrectomy: Technical note

PubMed Central

Mihmanlı, Mehmet; Köksal, Hakan Mustafa; Demir, Uygar; Işıl, Rıza Gürhan

2016-01-01

Objective: The esophago-gastric junction may be challenging during total gastrectomy due to gastric cancer. This situation may compromise the security of both the dissection and anastomosis. The purpose of this study was to investigate the usefulness of xiphoidectomy to overcome this issue. Material and Methods: The files of patients who underwent total gastrectomy + D2 lymph node dissection due to proximal gastric cancer or cardia cancer between April 2002–December 2013 were retrospectively evaluated. We assessed the outcome in patients with xiphoidectomy in addition to the midline incision in terms of xiphoidectomy technique, xiphoidectomy time, and operative and postoperative complications. Results: Thirty cases were identified to undergo xiphoidectomy. Nineteen patients were male and 11 were female, with a mean age of 51 (21–80) years. The time required for xiphoidectomy was 7–15 minutes (mean 8.7 minutes). The mean additional time required for the closure of the incision in cases with xiphoidectomy was 2 minutes. There was minimal arterial bleeding from the diaphragmatic surface in one patient, which was controlled by electrocautery. Only two patients developed wound infection. Conclusion: Performing xiphoidectomy is quite easy, after a certain learning phase. The operative time was 7–15 minutes longer due to excision of xiphoid and closure of the related defect. Minor hemorrhage was a problem during surgery. There were no early or late post-operative complications. We suggest that the procedure is beneficial in selected cases with requirement of a wider operative field or better exposure of the esophago-gastric junction during total gastrectomy for gastric cancer, and recommend removal of the xiphoid bone PMID:26985158

Benefits of xiphoidectomy in total gastrectomy: Technical note.

PubMed

Mihmanlı, Mehmet; Köksal, Hakan Mustafa; Demir, Uygar; Işıl, Rıza Gürhan

2016-01-01

The esophago-gastric junction may be challenging during total gastrectomy due to gastric cancer. This situation may compromise the security of both the dissection and anastomosis. The purpose of this study was to investigate the usefulness of xiphoidectomy to overcome this issue. The files of patients who underwent total gastrectomy + D2 lymph node dissection due to proximal gastric cancer or cardia cancer between April 2002-December 2013 were retrospectively evaluated. We assessed the outcome in patients with xiphoidectomy in addition to the midline incision in terms of xiphoidectomy technique, xiphoidectomy time, and operative and postoperative complications. Thirty cases were identified to undergo xiphoidectomy. Nineteen patients were male and 11 were female, with a mean age of 51 (21-80) years. The time required for xiphoidectomy was 7-15 minutes (mean 8.7 minutes). The mean additional time required for the closure of the incision in cases with xiphoidectomy was 2 minutes. There was minimal arterial bleeding from the diaphragmatic surface in one patient, which was controlled by electrocautery. Only two patients developed wound infection. Performing xiphoidectomy is quite easy, after a certain learning phase. The operative time was 7-15 minutes longer due to excision of xiphoid and closure of the related defect. Minor hemorrhage was a problem during surgery. There were no early or late post-operative complications. We suggest that the procedure is beneficial in selected cases with requirement of a wider operative field or better exposure of the esophago-gastric junction during total gastrectomy for gastric cancer, and recommend removal of the xiphoid bone.

Video-Assisted Thoracic Surgical Lobectomy for Lung Cancer: Description of a Learning Curve.

PubMed

Yao, Fei; Wang, Jian; Yao, Ju; Hang, Fangrong; Cao, Shiqi; Cao, Yongke

2017-07-01

Video-assisted thoracic surgical (VATS) lobectomy is gaining popularity in the treatment of lung cancer. The aim of this study is to investigate the learning curve of VATS lobectomy by using multidimensional methods and to compare the learning curve groups with respect to perioperative clinical outcomes. We retrospectively reviewed a prospective database to identify 67 consecutive patients who underwent VATS lobectomy for lung cancer by a single surgeon. The learning curve was analyzed by using moving average and the cumulative sum (CUSUM) method. With the moving average and CUSUM analyses for the operation time, patients were stratified into two groups, with chronological order defining early and late experiences. Perioperative clinical outcomes were compared between the two learning curve groups. According to the moving average method, the peak point for operation time occurred at the 26th case. The CUSUM method also showed the operation time peak point at the 26th case. When results were compared between early- and late-experience periods, the operation time, duration of chest drainage, and postoperative hospital stay were significantly longer in the early-experience group (cases 1 to 26). The intraoperative estimated blood loss was significantly less in the late-experience group (cases 27 to 67). CUSUM charts showed a decreasing duration of chest drainage after the 36th case and shortening postoperative hospital stay after the 37th case. Multidimensional statistical analyses suggested that the learning curve for VATS lobectomy for lung cancer required ∼26 cases. Favorable intraoperative and postoperative care parameters for VATS lobectomy were observed in the late-experience group.

[Resection anastomosis of the small intestine by celioscopy in swine. Comparative experimental study between manual and mechanical anastomosis].

PubMed

Noël, P; Fagot, H; Fabre, J M; Mann, C; Quenet, F; Guillon, F; Baumel, H; Domergue, J

1994-01-01

Laparoscopic intestinal anastomosis is not very reliable and needs to be evaluate in an experimental model in animals before being performed in man. The purpose of this study was to evaluate the feasibility, efficacy and safety of manual anastomosis comparatively to the standard stapling suture. Twenty female pigs weighing 20 +/- 5 kg. were used for this study. A 5 cm ileal segment resection was performed under laparoscopy. The animals were assigned to 2 groups. Group I: 10 animals underwent end-to-end hand-swen anastomosis with Polyglactin 910, dec 1.5. Group II: 10 animals underwent side-to-side anastomosis using the Endo stapler. Operating time and anastomosis time were compared using the Mann-Whitney test for statistical analysis. On the 15th postoperative day, the animals were sacrificed and the anastomoses were evaluated. There was no operating death in the 2 groups. The operative time was significantly longer in group I than in group II (p < 0.01), with 180 +/- 40 min vs 49 +/- 25 min respectively. This difference was due to the anastomosis time of 130 +/- 40 min vs 16 +/- 6 min respectively (p < 0.01). There was 1 postoperative death related to fistula and peritonitis in group I and none in group II. The post-operative follow-ing showed 5 anastomotic leakages (4 in group I and 1 in group II) and 2 relative stenoses in group I. This study shows the simplicity and rapidity of performing stapling intestinal anastomosis under laparoscopy. Hand-sewn anastomosis is technically more difficult to perform under laparoscopy and requires a greater experience.

Prospective study comparing laparoscopic and open adenomectomy: Surgical and functional results.

PubMed

Garcia-Segui, A; Angulo, J C

Open adenomectomy (OA) is the surgery of choice for large volume benign prostatic hyperplasia, and laparoscopic adenomectomy (LA) represents a minimally invasive alternative. We present a long-term, prospective study comparing both techniques. The study consecutively included 199 patients with benign prostatic hyperplasia and prostate volumes>80g who were followed for more than 12 months. The patients underwent OA (n=97) or LA (n=102). We recorded and compared demographic and perioperative data, functional results and complications using a descriptive statistical analysis. The mean age was 69.2±7.7 years (range 42-87), and the mean prostate volume (measured by TRUS) was 112.1±32.7mL (range 78-260). There were no baseline differences among the groups in terms of age, ASA scale, prostate volume, PSA levels, Qmax, IPSS, QoL or treatments prior to the surgery. The surgical time (P<.0001) and catheter time (P<.0002) were longer in the LA group. Operative bleeding (P<.0001), transfusion rate (P=.0015) and mean stay (P<.0001) were significantly lower in the LA group. The LA group had a lower rate of complications (P=.04), but there were no significant differences between the groups in terms of major complications (Clavien score≥3) (P=.13) or in the rate of late complications (at one year) (P=.66). There were also no differences between the groups in the functional postoperative results: IPSS (P=.17), QoL (P=.3) and Qmax (P=.17). LA is a reasonable, safe and effective alternative that results in less bleeding, fewer transfusions, shorter hospital stays and lower morbidity than OA. LA has similar functional results to OA, at the expense of longer surgical times and longer catheter times. Copyright © 2016 AEU. Publicado por Elsevier España, S.L.U. All rights reserved.

Algorithms for searching Fast radio bursts and pulsars in tight binary systems.

NASA Astrophysics Data System (ADS)

Zackay, Barak

2017-01-01

Fast radio bursts (FRB's) are an exciting, recently discovered, astrophysical transients which their origins are unknown.Currently, these bursts are believed to be coming from cosmological distances, allowing us to probe the electron content on cosmological length scales. Even though their precise localization is crucial for the determination of their origin, radio interferometers were not extensively employed in searching for them due to computational limitations.I will briefly present the Fast Dispersion Measure Transform (FDMT) algorithm,that allows to reduce the operation count in blind incoherent dedispersion by 2-3 orders of magnitude.In addition, FDMT enables to probe the unexplored domain of sub-microsecond astrophysical pulses.Pulsars in tight binary systems are among the most important astrophysical objects as they provide us our best tests of general relativity in the strong field regime.I will provide a preview to a novel algorithm that enables the detection of pulsars in short binary systems using observation times longer than an orbital period.Current pulsar search programs limit their searches for integration times shorter than a few percents of the orbital period.Until now, searching for pulsars in binary systems using observation times longer than an orbital period was considered impossible as one has to blindly enumerate all options for the Keplerian parameters, the pulsar rotation period, and the unknown DM.Using the current state of the art pulsar search techniques and all computers on the earth, such an enumeration would take longer than a Hubble time. I will demonstrate that using the new algorithm, it is possible to conduct such an enumeration on a laptop using real data of the double pulsar PSR J0737-3039.Among the other applications of this algorithm are:1) Searching for all pulsars on all sky positions in gamma ray observations of the Fermi LAT satellite.2) Blind searching for continuous gravitational wave sources emitted by pulsars with non-axis-symmetric matter distribution.Previous attempts to conduct all of the above searches contained substantial sensitivity compromises.

Historical extension of operational NDVI products for livestock insurance in Kenya

NASA Astrophysics Data System (ADS)

Vrieling, Anton; Meroni, Michele; Shee, Apurba; Mude, Andrew G.; Woodard, Joshua; de Bie, C. A. J. M. (Kees); Rembold, Felix

2014-05-01

Droughts induce livestock losses that severely affect Kenyan pastoralists. Recent index insurance schemes have the potential of being a viable tool for insuring pastoralists against drought-related risk. Such schemes require as input a forage scarcity (or drought) index that can be reliably updated in near real-time, and that strongly relates to livestock mortality. Generally, a long record (>25 years) of the index is needed to correctly estimate mortality risk and calculate the related insurance premium. Data from current operational satellites used for large-scale vegetation monitoring span over a maximum of 15 years, a time period that is considered insufficient for accurate premium computation. This study examines how operational NDVI datasets compare to, and could be combined with the non-operational recently constructed 30-year GIMMS AVHRR record (1981-2011) to provide a near-real time drought index with a long term archive for the arid lands of Kenya. We compared six freely available, near-real time NDVI products: five from MODIS and one from SPOT-VEGETATION. Prior to comparison, all datasets were averaged in time for the two vegetative seasons in Kenya, and aggregated spatially at the administrative division level at which the insurance is offered. The feasibility of extending the resulting aggregated drought indices back in time was assessed using jackknifed R2 statistics (leave-one-year-out) for the overlapping period 2002-2011. We found that division-specific models were more effective than a global model for linking the division-level temporal variability of the index between NDVI products. Based on our results, good scope exists for historically extending the aggregated drought index, thus providing a longer operational record for insurance purposes. We showed that this extension may have large effects on the calculated insurance premium. Finally, we discuss several possible improvements to the drought index.

TVT-O vs TVT: a randomized trial in patients with different degrees of urinary stress incontinence.

PubMed

Araco, F; Gravante, G; Sorge, R; Overton, J; De Vita, D; Sesti, F; Piccione, E

2008-07-01

TVT-O and TVT were compared in patients stratified according the severity of Stress Urinary Incontinence (SUI). Those patients with intrinsic sphincter deficiencies, overactive bladders, associated prolapses, neurovegetative disorders and recurrent SUI or under rehabilitative/medical therapies were all excluded. There were 208 women included. Operating times were longer, and postoperative pain greater for TVT (p < 0.001). TVT produced longer hospitalizations in severe SUI patients (p < 0.001). After 1 year of follow-up, incontinence was cured in all mild SUI patients with both techniques, in all severe SUI patients when treated with TVT and in 66% of them when treated with TVT-O (p < 0.001). Vaginal perforations occurred during the TVT-O (p = 0.01), bladder perforations during TVT (p = NS), bladder obstructions in mild SUI patients after TVT (p < 0.001). The severity of SUI is an important parameter that influences results after TVT-O and TVT, and could be used to guide surgeons in selecting the most effective intervention.

The ecology of eating: smaller portion sizes in France Than in the United States help explain the French paradox.

PubMed

Rozin, Paul; Kabnick, Kimberly; Pete, Erin; Fischler, Claude; Shields, Christy

2003-09-01

Part of the "French paradox" can be explained by the fact that the French eat less than Americans. We document that French portion sizes are smaller in comparable restaurants, in the sizes of individual portions of foods (but not other items) in supermarkets, in portions specified in cookbooks, and in the prominence of "all you can eat" restaurants in dining guides. We also present data, from observations at McDonald's, that the French take longer to eat than Americans. Our results suggest that in the domain of eating, and more generally, more attention should be paid to ecological factors, even though their mechanism of operation is transparent, and hence less revealing of fundamental psychological processes. Ironically, although the French eat less than Americans, they seem to eat for a longer period of time, and hence have more food experience. The French can have their cake and eat it as well.

The touchscreen operant platform for assessing executive function in rats and mice

PubMed Central

Mar, Adam C.; Horner, Alexa E.; Nilsson, Simon R.O.; Alsiö, Johan; Kent, Brianne A.; Kim, Chi Hun; Holmes, Andrew; Saksida, Lisa M.; Bussey, Timothy J.

2014-01-01

Summary This protocol details a subset of assays developed within the touchscreen platform to measure aspects of executive function in rodents. Three main procedures are included: Extinction, measuring the rate and extent of curtailing a response that was previously, but is no longer, associated with reward; Reversal Learning, measuring the rate and extent of switching a response toward a visual stimulus that was previously not, but has become, associated with reward (and away from a visual stimulus that was previously, but is no longer, rewarded); and the 5-Choice Serial Reaction Time (5-CSRT) task, gauging the ability to selectively detect and appropriately respond to briefly presented, spatially unpredictable visual stimuli. These methods were designed to assess both complimentary and overlapping constructs including selective and divided visual attention, inhibitory control, flexibility, impulsivity and compulsivity. The procedures comprise part of a wider touchscreen test battery assessing cognition in rodents with high potential for translation to human studies. PMID:24051960

Neural correlates of mathematical problem solving.

PubMed

Lin, Chun-Ling; Jung, Melody; Wu, Ying Choon; She, Hsiao-Ching; Jung, Tzyy-Ping

2015-03-01

This study explores electroencephalography (EEG) brain dynamics associated with mathematical problem solving. EEG and solution latencies (SLs) were recorded as 11 neurologically healthy volunteers worked on intellectually challenging math puzzles that involved combining four single-digit numbers through basic arithmetic operators (addition, subtraction, division, multiplication) to create an arithmetic expression equaling 24. Estimates of EEG spectral power were computed in three frequency bands - θ (4-7 Hz), α (8-13 Hz) and β (14-30 Hz) - over a widely distributed montage of scalp electrode sites. The magnitude of power estimates was found to change in a linear fashion with SLs - that is, relative to a base of power spectrum, theta power increased with longer SLs, while alpha and beta power tended to decrease. Further, the topographic distribution of spectral fluctuations was characterized by more pronounced asymmetries along the left-right and anterior-posterior axes for solutions that involved a longer search phase. These findings reveal for the first time the topography and dynamics of EEG spectral activities important for sustained solution search during arithmetical problem solving.

A simplified technique for polymethyl methacrylate cranioplasty: combined cotton stacking and finger fracture method.

PubMed

Kung, Woon-Man; Lin, Muh-Shi

2012-01-01

Polymethyl methacrylate (PMMA) is one of the most frequently used cranioplasty materials. However, limitations exist with PMMA cranioplasty including longer operative time, greater blood loss and a higher infection rate. To reduce these disadvantages, it is proposed to introduce a new surgical method for PMMA cranioplasty. Retrospective review of nine patients who received nine PMMA implants using combined cotton stacking and finger fracture method from January 2008 to July 2011. The definitive height of skull defect was quantified by computer-based image analysis of computed tomography (CT) scans. Aesthetic outcomes as measured by post-reduction radiographs and cranial index of symmetry (CIS), cranial nerve V and VII function and complications (wound infection, hardware extrusions, meningitis, osteomyelitis and brain abscess) were evaluated. The mean operation time for implant moulding was 24.56 ± 4.6 minutes and 178.0 ± 53 minutes for skin-to-skin. Average blood loss was 169 mL. All post-operative radiographs revealed excellent reduction. The mean CIS score was 95.86 ± 1.36%, indicating excellent symmetry. These results indicate the safety, practicability, excellent cosmesis, craniofacial symmetry and stability of this new surgical technique.

A brief historical review of non-anaesthetic causes of fires and explosions in the operating room.

PubMed

Macdonald, A G

1994-12-01

Fires and explosions have occurred in the operating theatre for many years. Flammable inhalation anaesthetic agents were responsible for many incidents in the past, but these are no longer available in many countries. Other causes of fires and explosions still exist in the operating theatre and, from time to time, result in serious and occasionally fatal injury. Flammable gastrointestinal gases have been the cause of injury to patients during gastric surgery, laparoscopy and during examination of the large bowel with electrical instrumentation. Gases formed in the bladder during urological procedures have ignited, causing rupture. Alcohol-based skin cleaning agents have resulted in severe burns to the skin. Equipment used for storage and delivery of oxygen to patients has caused fires in a variety of ways. Adhesive skin drapes have resulted recently in two tragic deaths. The increasing use of laser therapy, particularly in ear, nose and throat surgery, and in oral surgery, has brought about a renewed awareness of the risk of fire. The relevant factors which should be borne in mind and the precautions which should be adopted when laser therapy is to be used in the airway are discussed.

The VLA Low-band Ionosphere and Transient Experiment (VLITE)

NASA Astrophysics Data System (ADS)

Clarke, Tracy; Peters, Wendy; Brisken, Walter; Giacintucci, Simona; Kassim, Namir; Polisensky, Emil; Helmboldt, Joseph; Richards, Emily E.; Erickson, Alan; Ray, Paul S.; Kerr, Matthew T.; Deneva, Julia; Coburn, William; Huber, Robert; Long, Jeff

2018-01-01

The VLA Low-band Ionosphere and Transient Experiment (VLITE, http://vlite.nrao.edu/ ) is a commensal low-frequency observing system that has been operational on the National Radio Astronomy Observatory's Karl G. Jansky Very Large Array (VLA) since late 2014. The separate optical paths of the prime-focus sub-GHz dipole feeds and the Cassegrain-focus 1-50 GHz feeds allow both systems to operate simultaneously with independent correlators. The initial 2.5 years of VLITE operation provided real-time correlation of 10 antennas across the 320-384 MHz band with a total observing time approaching 12,000 hours. During the summer of 2017, VLITE was upgraded to a total of 16 antennas (more than doubling the number of baselines) with enhanced correlator capabilities to enable correlation of the on-the-fly observing mode being used for the new NRAO VLA Sky Survey (VLASS).We present an overview of the VLITE system, including highlights of the complexities of a commensal observing program, sparse-array challenges, and scientific capabilities from our science-ready data pipeline. In the longer term, we seek a path to broadband expansion across all VLA antennas to develop a powerful new LOw Band Observatory (LOBO).

Dynamic situation assessment and prediction (DSAP)

NASA Astrophysics Data System (ADS)

Sisti, Alex F.

2003-09-01

The face of war has changed. We no longer have the luxury of planning campaigns against a known enemy operating under a well-understood doctrine, using conventional weapons and rules of engagement; all in a well-charted region. Instead, today's Air Force faces new, unforeseen enemies, asymmetric combat situations and unconventional warfare (Chem/Bio, co-location of military assets near civilian facilities, etc.). At the same time, the emergence of new Air Force doctrinal notions (e.g., Global Strike Task Force, Effects-Based Operations, the desire to minimize or eliminate any collateral damage, etc.)- while propounding the benefits that can be expected with the adoption of such concepts - also impose many new technical and operational challenges. Furthermore, future mission/battle commanders will need to assimilate a tremendous glut of available information, and still be expected to make quick-response decisions - and to quantify the effects of those decisions - all in the face of uncertainty. All these factors translate to the need for dramatic improvements in the way we plan, rehearse, execute and dynamically assess the status of military campaigns. This paper addresses these crucial and revolutionary requirements through the pursuit of a new simulation paradigm that allows a user to perform real-time dynamic situation assessment and prediction.

Percutaneous medial hemi-epiphysiodesis using a transphyseal screw for caput valgum associated with developmental dysplasia of the hip.

PubMed

Shin, Chang Ho; Hong, Wan Kee; Lee, Doo Jae; Yoo, Won Joon; Choi, In Ho; Cho, Tae-Joon

2017-11-14

The purpose of this study was to evaluate the radiologic outcome of percutaneous medial hemi-epiphysiodesis using a transphyseal screw for the management of caput valgum associated with developmental dysplasia of the hip (DDH). Eighteen hips (18 patients) having caput valgum treated with screw hemi-epiphysiodesis were followed for more than 2 years, and were included in this study. The mean age at the time of the index operation was 8.3 years (range, 4.3 to 10.7 years) and age at the latest follow-up was 12.2 years (range, 9.4 to 16.4 years). The screw in 5 hips was changed into a longer one at postoperative 21.8 months (range, 14 to 29 months) because the proximal femur outgrew the screw. The screws in 11 hips were removed at the mean age of 10.9 years (range, 8.0 to 14.5 years). We retrospectively analyzed the change in various radiologic parameters over time. The mean Hilgenreiner-epiphyseal angle (HEA) of the operated side was 5.1 ± 11.3° preoperatively, and increased to 20.6 ± 11.3° at the latest follow-up (p = 0.001). The mean difference of the HEA between the operated and contralateral sides was 16.9 ± 15.1° preoperatively, which decreased to 2.4 ± 12.4° at the latest follow-up (p = 0.008). The mean articulo-trochanteric distance of the operated side, which was 3.2 ± 5.5 mm longer than that of the contralateral side preoperatively, became 5.6 ± 9.1 mm shorter at the latest follow-up (p = 0.001). The ratio of femoral neck length of the operated side to that of the contralateral side decreased over the follow-up period. Acetabular shape as measured by the Sharp angle and acetabular roof angle and femoral head coverage as measured by lateral center-edge angle did not change significantly by the index operation. The ratio of medial joint space width of the operated side to that of the contralateral side did not change significantly. Screw medial hemi-epiphysiodesis can effectively correct caput valgum associated with DDH. However, this technique remains coxa brevis and does not seem to significantly affect acetabular morphology or reduce subluxation.

Weather Knowledge: No Longer the Privilege of Meteorologists and Weather Services - Information and the Overturning of the Gods

NASA Astrophysics Data System (ADS)

Leon, V. C.

2006-05-01

The advances in communications technology, sharing of data and information, are enabling the development of knowledge that was impossible a decade ago. A prime example is Meteorology students, regardless of their location, are now able to access and use massive amounts of current and historic hydro-meteorological data. This ability was the province of national weather services with their so expensive equipment in the not too distant past. Now, one only needs inexpensive personal computers and access to the Internet (with the help and vision of groups like Unidata) to study phenomena that affect society. There is no longer a need to operate expensive ground stations to be able to analyze satellite imagery, etc. Investigations of atmospheric phenomena are no longer restricted to students of Meteorology. Learners in diverse disciplines and increasingly amateurs are joining a vibrantly expanding community. There was a time when a medical doctor was a god. Now, as technology has allowed us to become better informed, we are increasingly capable of questioning diagnoses and making truly informed decisions. This talk will reflect the author's experience, thoughts, and some perspectives for the future, on "the extension of free and open information sharing in the pursuit of incubating international collaborations".

A comprehensive and efficient daily quality assurance for PBS proton therapy

NASA Astrophysics Data System (ADS)

Actis, O.; Meer, D.; König, S.; Weber, D. C.; Mayor, A.

2017-03-01

There are several general recommendations for quality assurance (QA) measures, which have to be performed at proton therapy centres. However, almost each centre uses a different therapy system. In particular, there is no standard procedure for centres employing pencil beam scanning and each centre applies a specific QA program. Gantry 2 is an operating therapy system which was developed at PSI and relies on the most advanced technological innovations. We developed a comprehensive daily QA program in order to verify the main beam characteristics to assure the functionality of the therapy delivery system and the patient safety system. The daily QA program entails new hardware and software solutions for a highly efficient clinical operation. In this paper, we describe a dosimetric phantom used for verifying the most critical beam parameters and the software architecture developed for a fully automated QA procedure. The connection between our QA software and the database allows us to store the data collected on a daily basis and use it for trend analysis over longer periods of time. All the data presented here have been collected during a time span of over two years, since the beginning of the Gantry 2 clinical operation in 2013. Our procedure operates in a stable way and delivers the expected beam quality. The daily QA program takes only 20 min. At the same time, the comprehensive approach allows us to avoid most of the weekly and monthly QA checks and increases the clinical beam availability.

Advantages for passengers and cabin crew of operating a gas-phase adsorption air purifier in 11-h simulated flights.

PubMed

Strøm-Tejsen, P; Zukowska, D; Fang, L; Space, D R; Wyon, D P

2008-06-01

Experiments were carried out in a three-row, 21-seat section of a simulated aircraft cabin installed in a climate chamber to evaluate the extent to which passengers' perception of cabin air quality is affected by the operation of a gas-phase adsorption (GPA) purification unit. A total of 68 subjects, divided into four groups of 17 subjects took part in simulated 11-h flights. Each group experienced four conditions in balanced order, defined by two outside air supply rates (2.4 and 3.3 l/s per person), with and without the GPA purification unit installed in the recirculated air system, a total of 2992 subject-hours of exposure. During each flight the subjects completed questionnaires five times to provide subjective assessments of air quality, cabin environment, intensity of symptoms, and thermal comfort. Additionally, the subjects' visual acuity, finger temperature, skin dryness, and nasal peak flow were measured three times during each flight. Analysis of the subjective assessments showed that operating a GPA unit in the recirculated air provided consistent advantages with no apparent disadvantages. Operating a gas-phase adsorption (GPA) air purifier unit in the recirculated air in a simulated airplane cabin provided a clear and consistent advantage for passengers and crew that became increasingly apparent at longer flight times. This finding indicates that the expense of undertaking duly blinded field trials on revenue flights would be justified.

Quality of Communication in Robotic Surgery and Surgical Outcomes.

PubMed

Schiff, Lauren; Tsafrir, Ziv; Aoun, Joelle; Taylor, Andrew; Theoharis, Evan; Eisenstein, David

2016-01-01

Robotic surgery has introduced unique challenges to surgical workflow. The association between quality of communication in robotic-assisted laparoscopic surgery and surgical outcomes was evaluated. After each gynecologic robotic surgery, the team members involved in the surgery completed a survey regarding the quality of communication. A composite quality-of-communication score was developed using principal component analysis. A higher composite quality-of-communication score signified poor communication. Objective parameters, such as operative time and estimated blood loss (EBL), were gathered from the patient's medical record and correlated with the composite quality-of-communication scores. Forty robotic cases from March through May 2013 were included. Thirty-two participants including surgeons, circulating nurses, and surgical technicians participated in the study. A higher composite quality-of-communication score was associated with greater EBL (P = .010) and longer operative time (P = .045), after adjustment for body mass index, prior major abdominal surgery, and uterine weight. Specifically, for every 1-SD increase in the perceived lack of communication, there was an additional 51 mL EBL and a 31-min increase in operative time. The most common reasons reported for poor communication in the operating room were noise level (28/36, 78%) and console-to-bedside communication problems (23/36, 64%). Our study demonstrates a significant association between poor intraoperative team communication and worse surgical outcomes in robotic gynecologic surgery. Employing strategies to decrease extraneous room noise, improve console-to-bedside communication and team training may have a positive impact on communication and related surgical outcomes.

Preventive medicine for von Hippel-Lindau disease-associated pancreatic neuroendocrine tumors.

PubMed

Krauss, Tobias; Ferrara, Alfonso Massimiliano; Links, Thera P; Wellner, Ulrich; Bancos, Irina; Kvachenyuk, Andrey; Villar Gómez de Las Heras, Karina; Yukina, Marina; Petrov, Roman; Bullivant, Garrett; von Duecker, Laura; Jadhav, Swati S; Ploeckinger, Ursula; Welin, Staffan; Schalin-Jantti, Camilla; Gimm, Oliver; Pfeifer, Marija; Ngeow, Joanne; Hasse-Lazar, Kornelia; Sanso, Gabriela; Qi, Xiao-Ping; Ugurlu, Umit; Diaz, Rene Eduardo; Wohllk, Nelson; Peczkowska, Mariola; Aberle, Jens; Lourenço, Delmar Muniz; Pereira, Maria Adelaide; Fragoso, Maria Candida Barisson Villares; Hoff, Ana O; Almeida, Madson Queiroz; Violante, Alice H D; Quidute, Ana R P; Zhang, Zheiwei; Recasens, Monica; Robles Diaz, Luis; Kunavisarut, Tada; Wannachalee, Taweesak; Sirinvaravong, Sirinart; Jonasch, Eric; Grozinsky-Glasberg, Simona; Fraenkel, Merav; Beltsevich, Dmitry; Egorov, Viacheslav I; Bausch, Dirk; Schott, Matthias; Tiling, Nikolaus; Pennelli, Gianmaria; Zschiedrich, Stefan; Därr, Roland; Ruf, Juri; Denecke, Timm; Link, Karl-Heinrich; Zovato, Stefania; von Dobschuetz, Ernst; Yaremchuk, Svetlana; Amthauer, Holger; Makay, Ozer; Patocs, Attila; Walz, Martin K; Huber, Tobias B; Seufert, Jochen; Hellman, Per; Kim, Raymond H; Kuchinskaya, Ekaterina; Schiavi, Francesca; Malinoc, Angelica; Reisch, Nicole; Jarzab, Barbara; Barontini, Marta; Januszewicz, Andrzej; Shah, Nalini; Young, William; Opocher, Giuseppe; Eng, Charis; Neumann, Hartmut P H; Bausch, Birke

2018-05-10

Pancreatic neuroendocrine tumors (PanNETs) are rare in von Hippel-Lindau disease (VHL) but cause serious morbidity and mortality. Management guidelines for VHL-PanNETs continue to be based on limited evidence, and survival data to guide surgical management are lacking. We established the European-American-Asian-VHL-PanNET-Registry to assess data for risks for metastases, survival and long-term outcomes to provide best management recommendations. Of 2,330 VHL patients, 273 had a total of 484 PanNETs. Median age at diagnosis of PanNET was 35 years (range 10-75). Fifty-five (20%) patients had metastatic PanNETs. Metastatic PanNETs were significantly larger (median size 5 vs 2 cm; P<0.001) and tumor volume doubling time (TVDT) was faster (22 vs 126 months; P=0.001). All metastatic tumors were ≥2.8 cm. Codons 161 and 167 were hotspots for VHL germline mutations with enhanced risk for metastatic PanNETs. Multivariate prediction modeling disclosed maximum tumor diameter and TVDT as significant predictors for metastatic disease (positive and negative predictive values of 51% and 100% for diameter cutoff ≥2.8 cm, 44% and 91% for TVDT cutoff of ≤24 months). In 117/273 patients, PanNETs >1.5 cm in diameter were operated. Ten-year survival was significantly longer in operated vs non-operated patients, in particular for PanNETs <2.8cm vs ≥2.8 cm (94% vs 85% by 10 years; P=0.020; 80% vs 50% at 10 years; P=0.030). This study demonstrates that patients with PanNET approaching the cut-off diameter of 2.8 cm should be operated. Mutations in exon 3, especially of codons 161/167 are at enhanced risk for metastatic PanNETs. Survival is significantly longer in operated non-metastatic VHL-PanNETs.

[Laparoscopic surgery for perforated peptic ulcer].

PubMed

Yasuda, Kazuhiro; Kitano, Seigo

2004-03-01

Laparoscopic surgery has become the treatment of choice for the management of perforated peptic ulcer. The advantages of laparoscopic repair for perforated peptic ulcer include less pain, a short hospital stay, and an early return to normal activity. Although the operation time of laparoscopic surgery is significantly longer than that of open surgery, laparoscopic technique is safe, feasible, and with morbidity and mortality comparable to that of the conventional open technique. To benefit from the advantages offered by minimally invasive laparoscopic technique, further study will need to determine whether laparoscopic surgery is safe in patients with generalized peritonitis or sepsis.

Simplified Approach Charts Improve Data Retrieval Performance

PubMed Central

Stewart, Michael; Laraway, Sean; Jordan, Kevin; Feary, Michael S.

2016-01-01

The effectiveness of different instrument approach charts to deliver minimum visibility and altitude information during airport equipment outages was investigated. Eighteen pilots flew simulated instrument approaches in three conditions: (a) normal operations using a standard approach chart (standard-normal), (b) equipment outage conditions using a standard approach chart (standard-outage), and (c) equipment outage conditions using a prototype decluttered approach chart (prototype-outage). Errors and retrieval times in identifying minimum altitudes and visibilities were measured. The standard-outage condition produced significantly more errors and longer retrieval times versus the standard-normal condition. The prototype-outage condition had significantly fewer errors and shorter retrieval times than did the standard-outage condition. The prototype-outage condition produced significantly fewer errors but similar retrieval times when compared with the standard-normal condition. Thus, changing the presentation of minima may reduce risk and increase safety in instrument approaches, specifically with airport equipment outages. PMID:28491009

48 CFR 1845.7101-1 - Property classification.

Code of Federal Regulations, 2010 CFR

2010-10-01

... aeronautical and space programs, which are capable of stand-alone operation. Examples include research aircraft... characteristics. (ii) Examples of NASA heritage assets include buildings and structures designated as National...., it no longer provides service to NASA operations). Examples of obsolete property are items in...

48 CFR 1845.7101-1 - Property classification.

Code of Federal Regulations, 2011 CFR

2011-10-01

... aeronautical and space programs, which are capable of stand-alone operation. Examples include research aircraft... characteristics. (ii) Examples of NASA heritage assets include buildings and structures designated as National...., it no longer provides service to NASA operations). Examples of obsolete property are items in...

48 CFR 1845.7101-1 - Property classification.

Code of Federal Regulations, 2014 CFR

2014-10-01

... aeronautical and space programs, which are capable of stand-alone operation. Examples include research aircraft... characteristics. (ii) Examples of NASA heritage assets include buildings and structures designated as National...., it no longer provides service to NASA operations). Examples of obsolete property are items in...

48 CFR 1845.7101-1 - Property classification.

Code of Federal Regulations, 2013 CFR

2013-10-01

... aeronautical and space programs, which are capable of stand-alone operation. Examples include research aircraft... characteristics. (ii) Examples of NASA heritage assets include buildings and structures designated as National...., it no longer provides service to NASA operations). Examples of obsolete property are items in...

48 CFR 1845.7101-1 - Property classification.

Code of Federal Regulations, 2012 CFR

2012-10-01

... aeronautical and space programs, which are capable of stand-alone operation. Examples include research aircraft... characteristics. (ii) Examples of NASA heritage assets include buildings and structures designated as National...., it no longer provides service to NASA operations). Examples of obsolete property are items in...

Who is going to rescue the rescuers? Post-traumatic stress disorder among rescue workers operating in Greece during the European refugee crisis.

PubMed

Sifaki-Pistolla, Dimitra; Chatzea, Vasiliki-Eirini; Vlachaki, Sofia-Aikaterini; Melidoniotis, Evangelos; Pistolla, Georgia

2017-01-01

During the European refugee crisis, numerous Greek and international rescue workers are operating in Lesvos, offering search, rescue, and first aid services. Exposure to stressful life events while engaging in this rescue work can result in developing Post-Traumatic Stress Disorder (PTSD). The study aimed to assess the prevalence of PTSD and explore potential differences between different categories of rescuers. A cross-sectional study was conducted among 217 rescue workers. Participants were grouped according to affiliation: "Greek Professionals Rescuers/GPR", "International Professionals Rescuers/IPR" and "Volunteer Rescuers/VR". The PTSD Checklist-Civilian Version (PCL-C) was utilized. All tests were two-tailed (a = 0.05). Mann-Whitney, Kruskal-Wallis, and multivariate logistic regression were performed. Overall probable PTSD prevalence found was 17.1%. Rates varied significantly per rescuer's category; 23.1% in GPR, 11.8% in IPR, and 14.6% in VR (p = 0.02). GPR demonstrated the highest risk compared to IPR and VR (p < 0.001). Females had approximately two times higher risk. Other significant risk factors included marital status, age, and number of children. Lack of previous experience, longer operation period, longer shift hours, and handling dead refugees and dead children were also considered major risk factors. Rescue workers providing substantial aid to the refugees and migrants at Lesvos experience significant psychological distress. The present findings indicate the urgent need for targeted interventions. Further studies are needed to address long-term effects of the refugee crisis on rescuers, and explore effective measures to prevent PTSD.

Hydrodynamics study on drying of pepper in swirling fluidized bed dryer (SFBD)

NASA Astrophysics Data System (ADS)

Syaif Haron, Nazrul; Hazri Zakaria, Jamal; Faizal Mohideen Batcha, Mohd

2017-08-01

Malaysia is one of the pepper producer with exports quantity reaching more than 90000 tonnes between 2010 until 2016. Drying of pepper is mandatory before their export and at present, pepper was dried by sun drying to reduce cost. This conventional drying method was time consuming and may take four days during rainy season, which retards the production of pepper. This paper proposes the swirling fluidized bed drying (SFBD) method, which was known to have high mixing ability and improved solid-gas contact to shorten the drying time of products. A lab scale SFBD system was constructed to carry out this study. Hydrodynamic study was conducted for three beds loadings of 1.0 kg, 1.4 kg at a drying temperature of 90°C. The SFBD has shown excellent potential to dry the pepper with a relatively short drying time compared to the conventional method. Batch drying for the bed loads studied only took 3 hours of drying time only. It was found that bed higher bed loading of wet pepper requires longer drying time due to higher amount of moisture content in the bed. Four distinct regimes of operation were found during drying in the SFBD and these regimes offer flexibility of operation. The total bed pressure drop was relatively low during drying.

Study on solid liquid interface heat transfer of PCM under simultaneous charging and discharging (SCD) in horizontal cylinder annulus

NASA Astrophysics Data System (ADS)

Omojaro, Adebola Peter; Breitkopf, Cornelia

2017-07-01

Heat transfer performance during the simultaneous charging and discharging (SCD) operation process for phase change materials (PCM) contained inside the annulus of concentric horizontal cylinder was investigated. In the experimental set-up, the PCM inside the annulus serves as the heat sink along with an externally imposed forced cooling air. The obtained time wise temperature profile was used to determine the effects of different heat fluxes and the imposed forced convection cooling on the melt fraction values and the transition shift time from the observed conduction to natural convection heat transfer patterns. Furthermore, non-dimensional analysis was presented for the heat transfer at the interface to enable generalizing the result. Comparison of the results show that the SCD operation mode establish the condition that enables much PCM phase transition time and thus longer time of large latent heat transfer effect than the Partial and non simultaneous operations. Analysis results show that the variation of the heat flux for the SCD mode did not change the dominance of the natural convection over conduction heat transfers in the PCM. However, it significantly influences the commencement/transition shift time and melting rate while higher heat fluxes yields melt fraction that was 38-63% more for investigated process time. Variation with different cooling air flow rate shows more influences on the melt fraction than on the mode of heat transfer occurring in the PCM during melting. Available non-SCD modes correlation was shown to be insufficient to accurately predict interface heat transfer for the SCD modes.

Impact of body mass index on perioperative outcomes of laparoscopic radical nephrectomy in Japanese patients with clinically localized renal cell carcinoma.

PubMed

Miyake, Hideaki; Muramaki, Mototsugu; Tanaka, Kazushi; Takenaka, Atsushi; Fujisawa, Masato

2010-06-01

The aim of this study was to review the association between body mass index (BMI) and perioperative outcomes of laparoscopic radical nephrectomy (LRN) in Japanese patients with renal cell carcinoma (RCC). This study included 108 consecutive Japanese patients undergoing LRN for RCC between April 2001 and March 2009. These patients were divided into the following two groups according to BMI: the non-obese group (n= 58, BMI 25 kg/m(2) or less) and the obese group (n= 50, BMI greater than 25 kg/m(2)). Perioperative outcomes between these two groups were retrospectively compared. There were no significant differences in clinicopathological parameters other than BMI between the non-obese and obese groups. There were no significant differences in operative time, estimated blood loss during LRN, and the incidences of open conversion and postoperative complications between these two groups. In addition, there were no significant differences in parameters related to postoperative recovery, including time to walk, time to oral intake and time until permission for discharge, between these two groups. However, significant trends toward a prolonged operative time (P= 0.0050) and increased blood loss (P= 0.012) during LRN in relation to BMI were documented by linear regression analyses. Although the degree of obesity in patients included in this study was comparatively slight, these findings suggest that LRN can be safely performed for patients with RCC irrespective of BMI. However, the difficulty of LRN may increase with BMI considering the trends toward longer operative time as well as greater blood loss.

Wind measurements by electromagnetic probes

NASA Technical Reports Server (NTRS)

Susko, Michael

1989-01-01

The operation and performance characteristics of the Marshall Space Flight Center's Radar Wind Profiler, designed to provide measurement of the wind in the troposphere, are discussed. The Radar Wind Profiler uses a technology similar to that used in conventional Doppler radar systems, except the frequency is generally lower, antenna is larger, and dwell time is much longer. Its primary function is to monitor the vertical wind profile prior to launch of the Space Shuttle at more frequency intervals and nearer to launch time than is presently possible with the conventional balloon systems. A new wind profile will be obtained on the order of every 15 min based on an average of five wind profiles measured every 3 min at a height interval of 150 m to 20 km. The most significant features of the Radar Wind Profiler are the continuity in time and reliability.

Influence of magnetocrystalline anisotropy on the magnetization dynamics of magnetic microstructures.

PubMed

Kaiser, A; Wiemann, C; Cramm, S; Schneider, C M

2009-08-05

The study of magnetodynamics using stroboscopic time-resolved x-ray photoemission electron microscopy (TR-XPEEM) involves an intrinsic timescale provided by the pulse structure of the synchrotron radiation. In the usual multi-bunch operation mode, the time span between two subsequent light pulses is too short to allow a relaxation of the system into the ground state before the next pump-probe cycle starts. Using a deflection gating mechanism described in this paper we are able to pick the photoemission signal resulting from selected light pulses. Thus, PEEM measurements can be carried out in a flexible timing scheme with longer delays between two light pulses. Using this technique, the magnetodynamics of both Permalloy and iron structures have been investigated. The differences in the dynamic response on a short magnetic field pulse are discussed with respect to the magnetocrystalline anisotropy.

Measurements of quasiparticle tunneling dynamics in a band-gap-engineered transmon qubit.

PubMed

Sun, L; DiCarlo, L; Reed, M D; Catelani, G; Bishop, Lev S; Schuster, D I; Johnson, B R; Yang, Ge A; Frunzio, L; Glazman, L; Devoret, M H; Schoelkopf, R J

2012-06-08

We have engineered the band gap profile of transmon qubits by combining oxygen-doped Al for tunnel junction electrodes and clean Al as quasiparticle traps to investigate energy relaxation due to quasiparticle tunneling. The relaxation time T1 of the qubits is shown to be insensitive to this band gap engineering. Operating at relatively low-E(J)/E(C) makes the transmon transition frequency distinctly dependent on the charge parity, allowing us to detect the quasiparticles tunneling across the qubit junction. Quasiparticle kinetics have been studied by monitoring the frequency switching due to even-odd parity change in real time. It shows the switching time is faster than 10  μs, indicating quasiparticle-induced relaxation has to be reduced to achieve T1 much longer than 100  μs.

Cyclic fatigue of endodontic nickel titanium rotary instruments: static and dynamic tests.

PubMed

Li, Uei-Ming; Lee, Bor-Shiunn; Shih, Chin-Tsai; Lan, Wan-Hong; Lin, Chun-Pin

2002-06-01

Endodontic instruments upon rotation are subjected to both tensile and compressive stress in curved canals. This stress is localized at the point of curvature. The purpose of this study was to evaluate the cyclic fatigue of 0.04 ProFile nickel titanium rotary instruments operating at different rotational speeds and varied distances of pecking motion in metal blocks that simulated curved canals. A total of 150 ProFile instruments were made to rotate freely in sloped metal blocks at speeds of 200, 300, or 400 rpm by a contra-angle handpiece mounted on an Instron machine. The electric motor and Instron machine were activated until the instruments were broken in two different modes, static and dynamic pecking-motion. The fractured surfaces of separated instruments were examined under a scanning electron microscope. All data obtained were analyzed by a stepwise multiple regression method using a 95% confidence interval. The results demonstrated that the time to failure significantly decreased as the angles of curvature or the rotational speeds increased. However, as pecking distances increased, the time to failure increased. This is because a longer pecking distance gives the instrument a longer time interval before it once again passes through the highest stress area. Microscopic evaluation indicated that ductile fracture was the major cyclic failure mode. To prevent breakage of a NiTi rotary instrument, appropriate rotational speeds and continuous pecking motion in the root canals are recommended.

Sailing ships for research

NASA Astrophysics Data System (ADS)

Richman, Barbara T.

Motor-assisted sailing ships for ocean research could perform as well as or better than many existing research vessels and could cut fuel consumption by 50-80%, according to a preliminary study by an ad hoc panel of the National Research Council's Ocean Sciences Board (OSB).Rising fuel costs plague ship owners and operators. For example, 2 years ago the U.S. oceanographic fleet had a $6 million overrun in fuel costs. Furthermore, the price of marine diesel fuel skyrocketed from $3 per barrel in 1972 to about $38 per barrel in late 1980. Cutting these costs would be welcome if the savings were not made at the expense of additional crew, longer transit times, or less efficient scientific operations. A sailing ship with auxiliary motor propulsion is a promising prospect, according to the Ad Hoc Panel on the Use of Sailing Ships for Oceanography.

Control strategies for a telerobot

NASA Technical Reports Server (NTRS)

Ohara, John; Stasi, Bill

1989-01-01

One of the major issues impacting the utility of telerobotic systems for space is the development of effective control strategies. For near-term applications, telerobot control is likely to utilize teleoperation methodologies with integrated supervisory control capabilities to assist the operator. Two different approaches to telerobotic control are evaluated: bilateral force reflecting master controllers and proportional rate six degrees-of-freedom hand controllers. The controllers' performance of single manipulator arm tasks is compared. Simultaneous operation of both manipulator arms and complex multiaxis slave arm movements is investigated. Task times are significantly longer and fewer errors are committed with the hand controllers. The hand controllers are also rated significantly higher in cognitive and manual control workload on the two-arm task. The master controllers are rated significantly higher in physical workload. The implications of these findings for space teleoperations and higher levels of control are discussed.

Robotics in reproductive surgery: strengths and limitations.

PubMed

Catenacci, M; Flyckt, R L; Falcone, T

2011-09-01

Minimally invasive surgical techniques are becoming increasingly common in gynecologic surgery. However, traditional laparoscopy can be challenging. A robotic surgical system gives several advantages over traditional laparoscopy and has been incorporated into reproductive gynecological surgeries. The objective of this article is to review recent publications on robotically-assisted laparoscopy for reproductive surgery. Recent clinical research supports robotic surgery as resulting in less post-operative pain, shorter hospital stays, faster return to normal activities, and decreased blood loss. Reproductive outcomes appear similar to alternative approaches. Drawbacks of robotic surgery include longer operating room times, the need for specialized training, and increased cost. Larger prospective studies comparing robotic approaches with laparoscopy and conventional open surgery have been initiated and information regarding long-term outcomes after robotic surgery will be important in determining the ultimate utility of these procedures. Copyright © 2011 Elsevier Ltd. All rights reserved.

Alloy Selection for Accident Tolerant Fuel Cladding in Commercial Light Water Reactors

NASA Astrophysics Data System (ADS)

Rebak, Raul B.

2015-12-01

As a consequence of the March 2011 events at the Fukushima site, the U.S. congress asked the Department of Energy (DOE) to concentrate efforts on the development of nuclear fuels with enhanced accident tolerance. The new fuels had to maintain or improve the performance of current UO2-zirconium alloy rods during normal operation conditions and tolerate the loss of active cooling in the core for a considerably longer time period than the current system. DOE is funding cost-shared research to investigate the behavior of advanced steels both under normal operation conditions in high-temperature water [ e.g., 561 K (288 °C)] and under accident conditions for reaction with superheated steam. Current results show that, under accident conditions, the advanced ferritic steels (1) have orders of magnitude lower reactivity with steam, (2) would generate less hydrogen and heat than the current zirconium alloys, (3) are resistant to stress corrosion cracking under normal operation conditions, and (4) have low general corrosion in water at 561 K (288 °C).

How does processing affect storage in working memory tasks? Evidence for both domain-general and domain-specific effects.

PubMed

Jarrold, Christopher; Tam, Helen; Baddeley, Alan D; Harvey, Caroline E

2011-05-01

Two studies that examine whether the forgetting caused by the processing demands of working memory tasks is domain-general or domain-specific are presented. In each, separate groups of adult participants were asked to carry out either verbal or nonverbal operations on exactly the same processing materials while maintaining verbal storage items. The imposition of verbal processing tended to produce greater forgetting even though verbal processing operations took no longer to complete than did nonverbal processing operations. However, nonverbal processing did cause forgetting relative to baseline control conditions, and evidence from the timing of individuals' processing responses suggests that individuals in both processing groups slowed their responses in order to "refresh" the memoranda. Taken together the data suggest that processing has a domain-general effect on working memory performance by impeding refreshment of memoranda but can also cause effects that appear domain-specific and that result from either blocking of rehearsal or interference.

Inspection system qualification and integration into the mask manufacturing environment

NASA Astrophysics Data System (ADS)

LaVoy, Rosanne; Fujioka, Ron

1995-12-01

Integration of a mask inspection system into a manufacturing environment poses new challenges to both the inspection engineer and the equipment supplier. Traditional specifications (limited primarily to sensitivity and uptime) are no longer sufficient to successfully integrate a system into a 7 by 24 manufacturing area with multiple systems. Issues such as system sensitivity matching, sensitivity characterization by defect type, operator training and certification standards, and real-time SPC control of the systems must be addressed. This paper outlines some of the techniques Intel Mask Operation uses for integration of a new inspection system into the manufacturing line. Specifically moving a beta- site type tool out of the beta-site mode and into volume production. Examples are presented, including installation for manufacturing (including ergonomic modifications), techniques for system-to-system matching, use of SPC charts to monitor system performance, and operator training/certifications. Relationships between system PMs, or other environmental changes, and the system sensitivity SPC control charts also are discussed.

Impact of total hip arthroplasty on pain, walking ability, and cardiovascular fitness.

PubMed

Horstmann, Thomas; Vornholt-Koch, Sandra; Brauner, Torsten; Grau, Stefan; Mündermann, Annegret

2012-12-01

We tested the hypothesis that total hip arthroplasty (THA) patients have less pain and are able to walk longer post-operatively than pre-operatively, and that THA patients before and after have higher heart rates and compromised gas exchange determinants at rest and following exercise compared to healthy subjects with a post-operative improvement. Fifty-two patients completed questionnaires and an incremental walking stress test pre-operatively and 6-months after THA. Twenty-four age-matched control subjects completed the same stress test. Fifty-one patients had less pain 6-months after THA compared to pre-operative levels. Forty-three patients showed an improvement of at least one walking duration category. Patients had compromised cardiovascular fitness compared to the control group with a tendency to improve after THA. Hence, 6-months following THA, deficits exist other than reduced strength as reported in the literature. Prior to THA, the ability to walk longer is compromised by pain and not by poor cardiovascular fitness. Studies on specific rehabilitation programs of varying intensities may demonstrate opportunities to improve the cardiovascular fitness of this population. Copyright © 2012 Orthopaedic Research Society.

Comparison of posterior retroperitoneal and transabdominal lateral approaches in robotic adrenalectomy: an analysis of 200 cases.

PubMed

Kahramangil, Bora; Berber, Eren

2018-04-01

Although numerous studies have been published on robotic adrenalectomy (RA) in the literature, none has done a comparison of posterior retroperitoneal (PR) and transabdominal lateral (TL) approaches. The aim of this study was to compare the outcomes of robotic PR and TL adrenalectomy. This is a retrospective analysis of a prospectively maintained database. Between September 2008 and January 2017, perioperative outcomes of patients undergoing RA through PR and TL approaches were recorded into an IRB-approved database. Clinical and perioperative parameters were compared using Student's t test, Wilcoxon rank-sum test, and χ 2 test. Multivariate regression analysis was performed to determine factors associated with total operative time. 188 patients underwent 200 RAs. 110 patients were operated through TL and 78 patients through PR approach. Overall, conversion rate to open was 2.5% and 90-day morbidity 4.8%. The perioperative outcomes of TL and PR approaches were similar regarding estimated blood loss, rate of conversion to open, length of hospital stay, and 90-day morbidity. PR approach resulted in a shorter mean ± SD total operative time (136.3 ± 38.7 vs. 154.6 ± 48.4 min; p = 0.005) and lower visual analog scale pain score on postoperative day #1 (4.3 ± 2.5 vs. 5.4 ± 2.4; p = 0.001). After excluding tumors larger than 6 cm operated through TL approach, the difference in operative times persisted (136.3 ± 38.7 vs. 153.7 ± 45.7 min; p = 0.009). On multivariate regression analysis, increasing BMI and TL approaches were associated with longer total operative time. This study shows that robotic PR and TL approaches are equally safe and efficacious. With experience, shorter operative time and less postoperative pain can be achieved with PR technique. This supports the preferential utilization of PR approach in high-volume centers with enough experience.

Comprehensive comparing percutaneous endoscopic lumbar discectomy with posterior lumbar internal fixation for treatment of adjacent segment lumbar disc prolapse with stable retrolisthesis: A retrospective case-control study.

PubMed

Sun, Yapeng; Zhang, Wei; Qie, Suhui; Zhang, Nan; Ding, Wenyuan; Shen, Yong

2017-07-01

The study was to comprehensively compare the postoperative outcome and imaging parameter characters in a short/middle period between the percutaneous endoscopic lumbar discectomy (PELD) and the internal fixation of bone graft fusion (the most common form is posterior lumbar interbody fusion [PLIF]) for the treatment of adjacent segment lumbar disc prolapse with stable retrolisthesis after a previous lumbar internal fixation surgery.In this retrospective case-control study, we collected the medical records from 11 patients who received PELD operation (defined as PELD group) for and from 13 patients who received the internal fixation of bone graft fusion of lumbar posterior vertebral lamina decompression (defined as control group) for the treatment of the lumbar disc prolapse combined with stable retrolisthesis at Department of Spine Surgery, the Third Hospital of Hebei Medical University (Shijiazhuang, China) from May 2010 to December 2015. The operation time, the bleeding volume of perioperation, and the rehabilitation days of postoperation were compared between 2 groups. Before and after surgery at different time points, ODI, VAS index, and imaging parameters (including Taillard index, inter-vertebral height, sagittal dislocation, and forward bending angle of lumbar vertebrae) were compared.The average operation time, the blooding volume, and the rehabilitation days of postoperation were significantly less in PELD than in control group. The ODI and VAS index in PELD group showed a significantly immediate improving on the same day after the surgery. However, Taillard index, intervertebral height, sagittal dislocation in control group showed an immediate improving after surgery, but no changes in PELD group till 12-month after surgery. The forward bending angle of lumbar vertebrae was significantly increased and decreased in PELD and in control group, respectively.PELD operation was superior in terms of operation time, bleeding volume, recovery period, and financial support, if compared with lumbar internal fixation operation. Radiographic parameters reflect lumber structure changes, which could be observed immediately after surgery in both methods; however, the recoveries on nerve function and pain relief required a longer time, especially after PLIF operation.

Facilitating Analysis of Multiple Partial Data Streams

NASA Technical Reports Server (NTRS)

Maimone, Mark W.; Liebersbach, Robert R.

2008-01-01

Robotic Operations Automation: Mechanisms, Imaging, Navigation report Generation (ROAMING) is a set of computer programs that facilitates and accelerates both tactical and strategic analysis of time-sampled data especially the disparate and often incomplete streams of Mars Explorer Rover (MER) telemetry data described in the immediately preceding article. As used here, tactical refers to the activities over a relatively short time (one Martian day in the original MER application) and strategic refers to a longer time (the entire multi-year MER missions in the original application). Prior to installation, ROAMING must be configured with the types of data of interest, and parsers must be modified to understand the format of the input data (many example parsers are provided, including for general CSV files). Thereafter, new data from multiple disparate sources are automatically resampled into a single common annotated spreadsheet stored in a readable space-separated format, and these data can be processed or plotted at any time scale. Such processing or plotting makes it possible to study not only the details of a particular activity spanning only a few seconds, but also longer-term trends. ROAMING makes it possible to generate mission-wide plots of multiple engineering quantities [e.g., vehicle tilt as in Figure 1(a), motor current, numbers of images] that, heretofore could be found only in thousands of separate files. ROAMING also supports automatic annotation of both images and graphs. In the MER application, labels given to terrain features by rover scientists and engineers are automatically plotted in all received images based on their associated camera models (see Figure 2), times measured in seconds are mapped to Mars local time, and command names or arbitrary time-labeled events can be used to label engineering plots, as in Figure 1(b).

Utilization of Total Joint Arthroplasty in Physician-Owned Specialty Hospitals vs Acute Care Facilities.

PubMed

Chen, Antonia F; Pflug, Emily; O'Brien, Daniel; Maltenfort, Mitchell G; Parvizi, Javad

2017-07-01

The recent emergence of physician-owned specialty hospitals has sparked controversy about overutilization. Thus, the purpose of this study was to compare utilization patterns of total joint arthroplasty (TJA) between physician-specialty hospitals (PSHs) and acute care hospitals (ACHs). A retrospective study was conducted from January 2010 to August 2014 comparing primary TJA patients between a PSH and an ACH; 103 PSH patients were matched to 103 ACH patients by age, gender, BMI, and ASA classification with similar case distribution between facilities. All surgeons in the study operated at both hospitals and were shareholders of the PSH. Information on nonoperative treatments, and timing to the initial appointment, consent, and surgery were analyzed using univariate analysis. Nonoperative treatments before surgery were similar between hospitals (P = 1.00). The time from the initial appointment to consent was longer for PSH (P = .0001). However, the time from consent to the date of surgery (P = .04) and the timing from symptoms to initial appointment (P = .006) was shorter for PSH. The time from initial appointment to the day of surgery was similar between groups (P = .20). Patients were more likely to be consented for surgery on their first clinic visit when undergoing surgery at ACH (87 of 103, 84.4%) compared to PSH (61 of 103; 59.2%; P < .001). Length of stay was significantly shorter for both total knee arthroplasty (P = .001) and total hip arthroplasty patients (P = .001) at PSH. Facility ownership in PSH resulted in similar conservative treatment before TJA. The time to surgical consent after the initial appointment was longer PSH, whereas the time from consent to the date of surgery was shorter at the PSH. Copyright © 2017 Elsevier Inc. All rights reserved.

Radiation exposure, and procedure and fluoroscopy times in endovascular treatment of intracranial aneurysms: a methodological comparison.

PubMed

Cheung, Nicholas K; Boutchard, Michelle; Carr, Michael W; Froelich, Jens J

2018-01-09

Limited data are available for radiation exposure, and procedure and fluoroscopy times in neuroendovascular treatment (NET) strategies. This study establishes and compares related parameters between coil embolization (COIL), balloon assisted coil embolization (BAC), stent assisted coil embolization (SAC), and flow diverting technology (FDT) in NET of intracranial aneurysms. Between 2010 and 2017, 249 consecutive intracranial aneurysms underwent NET at a single center, all performed by the same operator. Dose area products (DAP), and procedure and fluoroscopy times were recorded and compared between COIL, BAC, SAC, and FDT techniques. Differences in parameters between cohorts were analyzed for significance using the Mann-Whitney U test, unpaired t test and χ 2 test. Additional subgroup analysis was performed for emergency and elective cases. 83 aneurysms were treated with COIL (33%), 72 with BAC (29%), 61 with SAC (25%), and 33 with FDT (13%). Baseline characteristics were largely similar within these groups (P>0.05). Among COIL, BAC, and FDT cohorts, no significant difference was found for mean DAP, or procedure and fluoroscopy times (P>0.05). However, compared with all other cohorts, SAC was associated with a significantly higher DAP and longer procedure and fluoroscopy times (P<0.005). No significant difference was recorded for emergency and elective case subgroups. Compared with other NET strategies, SAC was associated with a significantly higher DAP, and longer procedure and fluoroscopy times. This study provides an initial dataset regarding radiation exposure, and procedure and fluoroscopy times for common NET, and may assist ALARA (As Low As Reasonably Achievable) principles to reduce radiation risks. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

A single-dose regimen for antimicrobial prophylaxis to prevent perioperative infection in urological clean and clean-contaminated surgery.

PubMed

Higuchi, Yoshihide; Takesue, Yoshio; Yamada, Yusuke; Ueda, Yasuo; Suzuki, Toru; Aihara, Kinue; Maruyama, Takuo; Kondoh, Nobuyuki; Nojima, Michio; Yamamoto, Shingo

2011-04-01

A single dose of antimicrobial prophylaxis (AMP) was administered parenterally for the prevention of perioperative infection in a total of 788 patients undergoing urological surgery, including 380 endoscopic-instrumental, 328 clean, and 80 clean-contaminated operations performed at our institute between January 2007 and December 2009. Surgical site infections (SSIs), urinary tract infections (UTIs), and remote infections (RIs) were prospectively surveyed. The definition for a single dose of AMP allowed for the administration of an additional dose of an antimicrobial during surgery if the procedure was longer than 3 h, but not for the parenteral or oral administration at the end of the procedure in the recovery room, or at a later time over a period of more than 24 h. UTI was observed in 12 (3.2%) patients after endoscopic-instrumental operation, 1 (0.3%) after clean operation, and 1 (0.9%) after clean-contaminated operation. SSI was observed in 2 (0.6%) patients after clean operation but in none after clean-contaminated operations. RI was observed in 1 (0.3%) patient after endoscopic-instrumental operation, 3 (0.9%) after clean operation, and none after clean-contaminated operations. A single-dose regimen of AMP was effective and feasible for the prevention of perioperative infections, including SSIs, UTIs, and RIs, in endoscopic-instrumental, clean, and clean-contaminated urological surgical procedures.

A randomised comparison of AMBI, TGN and PFN for treatment of unstable trochanteric fractures.

PubMed

Papasimos, S; Koutsojannis, C M; Panagopoulos, A; Megas, P; Lambiris, E

2005-09-01

In this study, we initiated a prospective, randomised, clinical trial comparing the AMBI, TGN and PFN operations used for treatment of unstable fractures, for differences in intra-operative use, consolidation, complications and functional outcome. We have compared the pre-, intra- and post-operating variables of AMBI, TGN and PFN operations that were used for treatment of unstable trochanteric fractures, of 120 patients all above 60 years old diagnosed with extracapsular hip fractures classified as AO Type 31-A2 or Type 31-A3. According to our results the three methods are comparable in the treatment of unstable trochanteric fractures of patients above 60 years old. The AMBI remains the gold standard for the fractures of trochanteric region. TGN has an easier and faster procedure, facilitates early weight bearing and had minor late complications. An improper use of the PFN system was the reason for the most complications and the longer operation time of the device. PFN is also an accepted minimally invasive implant for unstable proximal femoral fractures but future modification of the implant to avoid Z-effect phenomenon, careful surgical technique and selection of the patients should reduce its high complication rate.

Operation Results of the Kstar Helium Refrigeration System

NASA Astrophysics Data System (ADS)

Chang, H.-S.; Fauve, E.; Park, D.-S.; Joo, J.-J.; Moon, K.-M.; Cho, K.-W.; Na, H. K.; Kwon, M.; Yang, S.-H.; Gistau-Baguer, G.

2010-04-01

The "first plasma" (100 kA of controllable plasma current for 100 ms) of KSTAR has been successfully generated in July 2008. The major outstanding feature of KSTAR compared to most other Tokamaks is that all the magnet coils are superconducting (SC), which enables higher plasma current values for a longer time duration when the nominal operation status has been reached. However, to establish the operating condition for the SC coils, other cold components, such as thermal shields, coil-supporting structures, SC buslines, and current leads also must be maintained at proper cryogenic temperature levels. A helium refrigeration system (HRS) with an exergetic equivalent cooling power of 9 kW at 4.5 K has been installed for such purposes and successfully commissioned. In this proceeding, we will report on the operation results of the HRS during the first plasma campaign of KSTAR. Using the HRS, the 300-ton cold mass of KSTAR was cooled down from ambient to the operating temperature levels of each cold component. Stable and steady cryogenic conditions, proper for the generation of the "first plasma" have been maintained for three months, after which, all of the cold mass was warmed up again to ambient temperature.

Ptolemy operations at the surface of a comet, from planning to reality

NASA Astrophysics Data System (ADS)

Morse, A. D.; Andrews, D. J.; Morgan, G. H.; Sheridan, S.; Barber, S. J.; Wright, I. P.

2016-08-01

Ptolemy is a Gas Chromatograph-Isotope Ratio-Mass Spectrometer (GC-IR-MS) aboard the Philae lander element of the Rosetta mission to comet 67P/Churyumov-Gerasimenko. Developed to determine the chemical and stable light isotopic composition of cometary material, Ptolemy was conceived as a highly flexible instrument able to accommodate changes in operational functionality via software modification. This was considered essential to allow for different modes of operation not only in response to rapid/unexpected changes and opportunities, but also to longer-term shifts in priorities as the overall mission plan (and indeed cometary science in general) changed during the decades from initial concept to landing. Against the backdrop of events of the Philae landing, this paper describes the methods of instrument operation and rational behind them used to achieve the Ptolemy scientific results during the period 12-14th November 2014. In particular we demonstrate the importance of a flexible modular approach to the instrument architecture enabling complex instrument operations, especially in a situation where the environment of exploration is effectively unknown and some of the engineering solutions were being tested in the field for the first time.

Stability and safety of MA50 intraocular lens placed in the sulcus

PubMed Central

Kemp, P S; Oetting, T A

2015-01-01

Purpose To describe the safety and stability of sulcus placement of the MA50 intraocular lens (IOL). Patients and methods Consecutive patients with MA50 IOLs placed in the sulcus at the University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA, from 1997 to 2012 were identified. Inclusion criteria included patients with over 4 weeks of follow-up data. AEL was compared with incidence of IOL decentration using at two-tailed Student's t-test. Results Fifty eyes of 49 patients meeting the inclusion criteria were identified. Four weeks post-operatively, the average best-corrected visual acuity was 20/30. IOL decentration occurred in 14% of patients; patients with decentered IOLs had a significantly longer average AEL (25.37 mm) than patients whose IOL remained centered (23.94 mm, P=0.017). Other complications included uveitis-glaucoma-hyphema syndrome (12%), iritis (8%), and glaucoma (6%). There were no cases of pigment dispersion syndrome or need for lens exchange. Twelve eyes (24%) had intra-operative optic capture by the anterior capsule, none of which had post-operative decentration. Conclusion The MA50 IOL is a reasonable, stable option for placement in the sulcus, with a low-risk profile; however, in eyes with longer AEL and presumably larger anterior segment, surgeons should consider placing an IOL with longer haptic distance than the MA50 to maintain centration. Optic capture of the MA50 IOL by the anterior capsule should be considered for longer eyes, as it is protective against decentration. PMID:26139047

A Paradigm for Operant Conditioning in Blow Flies ("Phormia Terrae Novae" Robineau-Desvoidy, 1830)

ERIC Educational Resources Information Center

Sokolowski, Michel B. C.; Disma, Gerald; Abramson, Charles I.

2010-01-01

An operant conditioning situation for the blow fly ("Protophormia terrae novae") is described. Individual flies are trained to enter and reenter a hole as the operant response. Only a few sessions of contingent reinforcement are required to increase response rates. When the response is no longer followed by food, the rate of entering the hole…

The enhancement of rapidly quenched galaxies in distant clusters at 0.5 < z < 1.0

NASA Astrophysics Data System (ADS)

Socolovsky, Miguel; Almaini, Omar; Hatch, Nina A.; Wild, Vivienne; Maltby, David T.; Hartley, William G.; Simpson, Chris

2018-05-01

We investigate the relationship between environment and galaxy evolution in the redshift range 0.5 < z < 1.0. Galaxy overdensities are selected using a friends-of-friends algorithm, applied to deep photometric data in the Ultra-Deep Survey field. A study of the resulting stellar mass functions reveals clear differences between cluster and field environments, with a strong excess of low-mass rapidly quenched galaxies in cluster environments compared to the field. Cluster environments also show a corresponding deficit of young, low-mass star-forming galaxies, which show a sharp radial decline towards cluster centres. By comparing mass functions and radial distributions, we conclude that young star-forming galaxies are rapidly quenched as they enter overdense environments, becoming post-starburst galaxies before joining the red sequence. Our results also point to the existence of two environmental quenching pathways operating in galaxy clusters, operating on different time-scales. Fast quenching acts on galaxies with high specific star formation rates, operating on time-scales shorter than the cluster dynamical time (<1 Gyr). In contrast, slow quenching affects galaxies with moderate specific star formation rates, regardless of their stellar mass, and acts on longer time-scales (≳ 1 Gyr). Of the cluster galaxies in the stellar mass range 9.0 < log (M/M⊙) < 10.5 quenched during this epoch, we find that 73 per cent were transformed through fast quenching, while the remaining 27 per cent followed the slow quenching route.

Improving seasonal forecast through the state of large-scale climate signals

NASA Astrophysics Data System (ADS)

Samale, Chiara; Zimmerman, Brian; Giuliani, Matteo; Castelletti, Andrea; Block, Paul

2017-04-01

Increasingly uncertain hydrologic regimes are challenging water systems management worldwide, emphasizing the need of accurate medium- to long-term predictions to timely prompt anticipatory operations. In fact, forecasts are usually skillful over short lead time (from hours to days), but predictability tends to decrease on longer lead times. The forecast lead time might be extended by using climate teleconnection, such as El Nino Southern Oscillation (ENSO). Despite the ENSO teleconnection is well defined in some locations such as Western USA and Australia, there is no consensus on how it can be detected and used in other river basins, particularly in Europe, Africa, and Asia. In this work, we propose the use of the Nino Index Phase Analysis for capturing the state of multiple large-scale climate signals (i.e., ENSO, North Atlantic Oscillation, Pacific Decadal Oscillation, Atlantic Multidecadal Oscillation, Dipole Mode Index). This climate state information is used for distinguishing the different phases of the climate signals and for identifying relevant teleconnections between the observations of Sea Surface Temperature (SST) that mostly influence the local hydrologic conditions. The framework is applied to the Lake Como system, a regulated lake in northern Italy which is mainly operated for flood control and irrigation supply. Preliminary results show high correlations between SST and three to six months ahead precipitation in the Lake Como basin. This forecast represents a valuable information to partially anticipate the summer water availability, ultimately supporting the improvement of the Lake Como operations.

Vaginal sacrospinous colpopexy and laparoscopic sacral colpopexy for vaginal vault prolapse.

PubMed

Marcickiewicz, J; Kjöllesdal, M; Engh, M Ellström; Eklind, S; Axén, C; Brännström, M; Stjerndahl, J-H

2007-01-01

Vaginal sacrospinous colpopexy (VSC) and laparoscopic sacral colpopexy (LSC) both correct vault prolapse. The present study compares the perioperative course and long-term results of VSC and LSC. This retrospective study of post-hysterectomy vault prolapse involved 111 patients operated with either VSC (n=51) or LSC (n=60). The median time for the postoperative follow-up visit was 33.6 (range: 13-60) months for the LSC group and 38.4 (range: 7-108) months for the VSC group. Prolapse grade as well as the patient's satisfaction was recorded at the follow-up visit. Operation time was significantly shorter in the VSC group (median: 62 min) compared to the LSC group (median: 129 min). The rate of perioperative complications was low in both groups. There were 3 laparotomies in the LSC group, due to perioperative complications. The inpatients days were similar, with 3.7 days (1-18) and 4.0 days (2-21) in the VSC and the LSC group, respectively. Surgery for the recurrence of vault prolapse at any time before the follow-up visit did not occur in the VSC group, but occurred in 7 patients in the LSC group. At the follow-up visit, there was no recurrence of vault prolapse in either group. The subjective success rate was 82% in the VSC and 78% in the LSC group. This study indicates that VSC and LSC are two equally effective surgical procedures to correct vaginal vault prolapse, but the LSC technique requires a longer operating time.

Determining effective forecast horizons for multi-purpose reservoirs with short- and long-term operating objectives

NASA Astrophysics Data System (ADS)

Luchner, Jakob; Anghileri, Daniela; Castelletti, Andrea

2017-04-01

Real-time control of multi-purpose reservoirs can benefit significantly from hydro-meteorological forecast products. Because of their reliability, the most used forecasts range on time scales from hours to few days and are suitable for short-term operation targets such as flood control. In recent years, hydro-meteorological forecasts have become more accurate and reliable on longer time scales, which are more relevant to long-term reservoir operation targets such as water supply. While the forecast quality of such products has been studied extensively, the forecast value, i.e. the operational effectiveness of using forecasts to support water management, has been only relatively explored. It is comparatively easy to identify the most effective forecasting information needed to design reservoir operation rules for flood control but it is not straightforward to identify which forecast variable and lead time is needed to define effective hedging rules for operational targets with slow dynamics such as water supply. The task is even more complex when multiple targets, with diverse slow and fast dynamics, are considered at the same time. In these cases, the relative importance of different pieces of information, e.g. magnitude and timing of peak flow rate and accumulated inflow on different time lags, may vary depending on the season or the hydrological conditions. In this work, we analyze the relationship between operational forecast value and streamflow forecast horizon for different multi-purpose reservoir trade-offs. We use the Information Selection and Assessment (ISA) framework to identify the most effective forecast variables and horizons for informing multi-objective reservoir operation over short- and long-term temporal scales. The ISA framework is an automatic iterative procedure to discriminate the information with the highest potential to improve multi-objective reservoir operating performance. Forecast variables and horizons are selected using a feature selection technique. The technique determines the most informative combination in a multi-variate regression model to the optimal reservoir releases based on perfect information at a fixed objective trade-off. The improved reservoir operation is evaluated against optimal reservoir operation conditioned upon perfect information on future disturbances and basic reservoir operation using only the day of the year and the reservoir level. Different objective trade-offs are selected for analyzing resulting differences in improved reservoir operation and selected forecast variables and horizons. For comparison, the effective streamflow forecast horizon determined by the ISA framework is benchmarked against the performances obtained with a deterministic model predictive control (MPC) optimization scheme. Both the ISA framework and the MPC optimization scheme are applied to the real-world case study of Lake Como, Italy, using perfect streamflow forecast information. The principal operation targets for Lake Como are flood control and downstream water supply which makes its operation a suitable case study. Results provide critical feedback to reservoir operators on the use of long-term streamflow forecasts and to the hydro-meteorological forecasting community with respect to the forecast horizon needed from reliable streamflow forecasts.

Comparison of abdominal, vaginal, and laparoscopic hysterectomies in a tertiary care hospital in Turkey.

PubMed

Inal, Z O; Inal, H A

2018-05-01

The aim of this retrospective study was to assess and compare the clinical results of three hysterectomy techniques: abdominal hysterectomy (AH), vaginal hysterectomy (VH), and laparoscopic hysterectomy (LH). A total of 2163 patients having undergone AH (n = 1226), VH (n = 426), and LH (n = 511) procedures were analyzed. The mean age, body mass index (BMI), parity, uterus weight, operation time, blood loss, duration of hospitalization, analgesic needs, intra- and postoperative complications, and indications for hysterectomy were analyzed and compared. There were no differences between the groups with respect to the BMI, parity, and intra- or postoperative major and minor complications. The operation time was significantly shorter in the VH group than in the other two groups (p < 0.001), and the blood loss was significantly lower in the LH group than in the others (p < 0.001). The duration of hospitalization and analgesic needs were the shortest in the LH group (p < 0.001), while the uterus weight and previous intra-abdominal surgery rate were the lowest in the VH group (p < 0.001). Despite the fact that the LH exhibited a longer operation time than the VH, the LH was considered to be a safe and effective surgical procedure due to the lesser blood loss, hospital stay, and analgesic needs.

Surgeon and type of anesthesia predict variability in surgical procedure times.

PubMed

Strum, D P; Sampson, A R; May, J H; Vargas, L G

2000-05-01

Variability in surgical procedure times increases the cost of healthcare delivery by increasing both the underutilization and overutilization of expensive surgical resources. To reduce variability in surgical procedure times, we must identify and study its sources. Our data set consisted of all surgeries performed over a 7-yr period at a large teaching hospital, resulting in 46,322 surgical cases. To study factors associated with variability in surgical procedure times, data mining techniques were used to segment and focus the data so that the analyses would be both technically and intellectually feasible. The data were subdivided into 40 representative segments of manageable size and variability based on headers adopted from the common procedural terminology classification. Each data segment was then analyzed using a main-effects linear model to identify and quantify specific sources of variability in surgical procedure times. The single most important source of variability in surgical procedure times was surgeon effect. Type of anesthesia, age, gender, and American Society of Anesthesiologists risk class were additional sources of variability. Intrinsic case-specific variability, unexplained by any of the preceding factors, was found to be highest for shorter surgeries relative to longer procedures. Variability in procedure times among surgeons was a multiplicative function (proportionate to time) of surgical time and total procedure time, such that as procedure times increased, variability in surgeons' surgical time increased proportionately. Surgeon-specific variability should be considered when building scheduling heuristics for longer surgeries. Results concerning variability in surgical procedure times due to factors such as type of anesthesia, age, gender, and American Society of Anesthesiologists risk class may be extrapolated to scheduling in other institutions, although specifics on individual surgeons may not. This research identifies factors associated with variability in surgical procedure times, knowledge of which may ultimately be used to improve surgical scheduling and operating room utilization.

Robotic radical prostatectomy in overweight and obese patients: oncological and validated-functional outcomes.

PubMed

Wiltz, Aimee L; Shikanov, Sergey; Eggener, Scott E; Katz, Mark H; Thong, Alan E; Steinberg, Gary D; Shalhav, Arieh L; Zagaja, Gregory P; Zorn, Kevin C

2009-02-01

To determine the impact of body mass index (BMI) on perioperative functional and oncological outcomes in patients undergoing robotic laparoscopic radical prostatectomy (RLRP) when stratified by BMI. Data were collected prospectively for 945 consecutive patients undergoing RLRP. Patients were evaluated with the UCLA-PCI-SF36v2 validated-quality-of-life questionnaire preoperatively and postoperatively to 24 months. Patients were stratified by BMI as normal weight (BMI < 25 kg/m(2)), overweight (BMI = 25 to < 30 kg/m(2)) and obese (BMI > or = 30 kg/m(2)) for outcomes analysis. Preoperatively, obese men had a significantly greater percentage of medical comorbidities (P < .01) as well as a baseline erectile dysfunction (lower mean baseline Sexual Health Inventory for Men score [P = .01] and UCLA-PCI-SF36v2 sexual function domain scores [P = .01]). Mean operative time was significantly longer in obese patients when compared with normal and overweight men (234 minutes vs 217 minutes vs 214 minutes; P = .0003). Although overall complication rates were comparable between groups, a greater incidence of case abortion caused by pneumoperitoneal pressure with excessive airway pressures was noted in obese men. Urinary continence and potency outcomes were significantly lower for obese men at both 12 and 24 months (all P < .05). In this series, obese men experienced a longer operative time, particularly during the initial robotic experience. As such, surgeons early in their RLRP learning curve should proceed cautiously with surgery in these technically more difficult patients or reserve such cases until the learning curve has been surmounted. These details, including inferior urinary and sexual outcomes, should be discussed with obese patients during preoperative counseling.

The effect of cyclosporin-A on peri-operative myocardial injury in adult patients undergoing coronary artery bypass graft surgery: a randomised controlled clinical trial

PubMed Central

Hausenloy, DJ; Kunst, G; Boston-Griffiths, E; Kolvekar, S; Chaubey, S; John, L; Desai, J; Yellon, DM

2014-01-01

Objective Cyclosporin-A (CsA) has been reported to reduce myocardial infarct size in both the experimental and clinical settings. This protective effect is dependent on its ability to prevent the opening of the mitochondrial permeability transition pore, a critical determinant of cell death in the setting of acute ischaemia-reperfusion injury. Whether CsA can reduce the extent of peri-operative myocardial injury (PMI) in patients undergoing coronary artery bypass graft (CABG) surgery is unknown, and is investigated in this randomised controlled clinical trial. Methods 78 adult patients undergoing elective CABG surgery were randomised to receive either an intravenous bolus of CsA (2.5 mg/kg) or placebo administered after induction of anaesthesia and prior to sternotomy. PMI was assessed by measuring serum cardiac enzymes, troponin T (cTnT) and CK-MB at 0, 6, 12, 24, 48 and 72 h after surgery. Results There was no significant difference in mean peak cTnT levels between control (n=43) and CsA treatment (n=40) patients (0.56±0.06 ng/mL with control vs 0.35±0.05 ng/mL with CsA; p=0.07). However, in higher-risk patients with longer cardiopulmonary bypass times, there was a significant reduction in PMI with CsA therapy (p=0.049), with a reduced postoperative cTnT rise by 0.03 ng/mL for every 10 min, when compared with control. Conclusions In patients with longer cardiopulmonary bypass times, a single intravenous bolus of CsA administered prior to CABG surgery reduced the extent of PMI. PMID:24488610

Laparoscopic correction of perforated peptic ulcer: first choice? A review of literature.

PubMed

Bertleff, Mariëtta J O E; Lange, Johan F

2010-06-01

Perforated peptic ulcer (PPU), despite antiulcer medication and Helicobacter eradication, is still the most common indication for emergency gastric surgery associated with high morbidity and mortality. Outcome might be improved by performing this procedure laparoscopically, but there is no consensus on whether the benefits of laparoscopic closure of perforated peptic ulcer outweigh the disadvantages such as prolonged surgery time and greater expense. An electronic literature search was done by using PubMed and EMBASE databases. Relevant papers written between January 1989 and May 2009 were selected and scored according to Effective Public Health Practice Project guidelines. Data were extracted from 56 papers, as summarized in Tables 1-7. The overall conversion rate for laparoscopic correction of perforated peptic ulcer was 12.4%, with main reason for conversion being the diameter of perforation. Patients presenting with PPU were predominantly men (79%), with an average age of 48 years. One-third had a history of peptic ulcer disease, and one-fifth took nonsteroidal anti-inflammatory drugs (NSAIDs). Only 7% presented with shock at admission. There seems to be no consensus on the perfect setup for surgery and/or operating technique. In the laparoscopic groups, operating time was significant longer and incidence of recurrent leakage at the repair site was higher. Nonetheless there was significant less postoperative pain, lower morbidity, less mortality, and shorter hospital stay. There are good arguments that laparoscopic correction of PPU should be first treatment of choice. A Boey score of 3, age over 70 years, and symptoms persisting longer than 24 h are associated with higher morbidity and mortality and should be considered contraindications for laparoscopic intervention.

Laparoscopic Radical Prostatectomy after Previous Transurethral Resection of the Prostate in Clinical T1a and T1b Prostate Cancer: A Matched-Pair Analysis.

PubMed

Yang, Yi; Luo, Yun; Hou, Guo-Liang; Huang, Qun-Xiong; Lu, Min-Hua; Si-tu, Jie; Gao, Xin

2015-07-01

To analyze and compare surgical, oncological and functional outcomes of laparoscopic radi­cal prostatectomy (LRP) in patients with and without previous transurethral resection of the prostate (TURP). In total, 785 men underwent LRP at our institution from January 2002 to December 2012. TURP had been performed previously in 35 of these patients (TURP group). A matched-pair analysis iden­tified 35 additional men without previous TURP who exhibited equivalent clinicopathological characteristics to serve as a control group. Perioperative complications and surgical, functional, and oncological outcomes were compared between the two groups. The groups were similar in age, body mass index, serum prostate-specific antigen level, and pre- and post-operative Gleason scores. Patients in the TURP group had greater blood loss (231 vs. 139 mL), longer opera­tive times (262 vs. 213 min), a greater probability of transfusion (8.6% vs. 0%), and a higher rate of complications (37.1% vs. 11.4%) compared with the control group. The positive surgical margin rate was higher in the TURP group, but this difference was not statistically significant (P = .179). The continence rates at one year after surgery were similar, but a lower continence rate was identified in the TURP group (42.9% vs. 68.6%) at 3 months. Bio­chemical recurrence developed in 17.1% and 11.4% of the patients in the TURP and control groups, respectively, after a mean follow-up of 57.6 months. LRP is feasible but challenging after TURP. LRP entails longer operating times, greater blood loss, higher complication rates and worse short-term continence outcomes. However, the radical nature of this cancer surgery is not compromised.

Laparoscopic correction of perforated peptic ulcer: first choice? A review of literature

PubMed Central

Lange, Johan F.

2009-01-01

Background Perforated peptic ulcer (PPU), despite antiulcer medication and Helicobacter eradication, is still the most common indication for emergency gastric surgery associated with high morbidity and mortality. Outcome might be improved by performing this procedure laparoscopically, but there is no consensus on whether the benefits of laparoscopic closure of perforated peptic ulcer outweigh the disadvantages such as prolonged surgery time and greater expense. Methods An electronic literature search was done by using PubMed and EMBASE databases. Relevant papers written between January 1989 and May 2009 were selected and scored according to Effective Public Health Practice Project guidelines. Results Data were extracted from 56 papers, as summarized in Tables 1–7. The overall conversion rate for laparoscopic correction of perforated peptic ulcer was 12.4%, with main reason for conversion being the diameter of perforation. Patients presenting with PPU were predominantly men (79%), with an average age of 48 years. One-third had a history of peptic ulcer disease, and one-fifth took nonsteroidal anti-inflammatory drugs (NSAIDs). Only 7% presented with shock at admission. There seems to be no consensus on the perfect setup for surgery and/or operating technique. In the laparoscopic groups, operating time was significant longer and incidence of recurrent leakage at the repair site was higher. Nonetheless there was significant less postoperative pain, lower morbidity, less mortality, and shorter hospital stay. Conclusion There are good arguments that laparoscopic correction of PPU should be first treatment of choice. A Boey score of 3, age over 70 years, and symptoms persisting longer than 24 h are associated with higher morbidity and mortality and should be considered contraindications for laparoscopic intervention. PMID:20033725

Lunar and Mars Exploration: The Autonomy Factor

NASA Technical Reports Server (NTRS)

Rando, Cynthia M.; Schuh, Susan V.

2008-01-01

Long duration space flight crews have relied heavily on almost constant communication with ground control mission support. Ground control teams provide vehicle status and system monitoring, while offering near real time support for specific tasks, emergencies, and ensuring crew health and well being. With extended exploration goals to lunar and Mars outposts, real time communication with ground control teams and the ground s ability to conduct mission monitoring will be very limited compared to the resources provided to current International Space Station (ISS) crews. An operational shift toward more autonomy and a heavier reliance on the crew to monitor their vehicle and operations will be required for these future missions. NASA s future exploration endeavors and the subsequent increased autonomy will require a shift in crew skill composition, i.e. engineer, doctor, mission specialist etc. and lead to new training challenges and mission scenarios. Specifically, operational and design changes will be necessary in many areas including: Habitat Infrastructure and Support Systems, Crew Composition, Training, Procedures and Mission Planning. This paper will specifically address how to apply ISS lessons learned to further use ISS as a test bed to address decreased amounts of ground support to achieve full autonomous operations for lunar and Mars missions. Understanding these lessons learned and applying them to current operations will help to address the future impacts of increased crew autonomy for the lunar and Mars outposts and pave the way for success in increasingly longer mission durations.

Stapled haemorrhoidopexy for the treatment of haemorrhoids: a systematic review.

PubMed

Burch, J; Epstein, D; Sari, A Baba-Akbari; Weatherly, H; Jayne, D; Fox, D; Woolacott, N

2009-03-01

This systematic review aimed to evaluate the short- and long-term safety, efficacy and costs of stapled haemorrhoidopexy (SH) compared with conventional haemorrhoidectomy. We searched 26 electronic databases and websites for studies in any language up to July 2006. Inclusion criteria were predefined, and each stage of the review process was conducted in duplicate. Twenty-seven randomized controlled trials were included (n = 2279). All had some methodological flaws. Postoperatively, 19 trials (95%) reported less pain, 17 (89%) reported a shorter operating time, 14 (88%) a shorter hospital stay, and 14 (93%) a shorter convalescence time following SH. However, prolapse was significantly more common after SH (OR 3.38; 95% CI: 1.00, 11.47). In the longer term, prolapse was significantly more common after SH (OR 4.34; 95% CI: 1.67, 11.28) as was reintervention for prolapse (OR 6.78; 95% CI: 2.00, 23.00). There were no differences in the rate or type of complications. Conventional haemorrhoidectomy and SH had similar costs during the initial admission. Compared with conventional haemorrhoidectomy, SH resulted in less postoperative pain, shorter operating time, a shorter hospital stay, and a shorter convalescence, but a higher rate of prolapse and reintervention for prolapse.

Single-pulse picking at kHz repetition rates using a Ge plasma switch at the free-electron laser FELBE.

PubMed

Schmidt, J; Winnerl, S; Seidel, W; Bauer, C; Gensch, M; Schneider, H; Helm, M

2015-06-01

We demonstrate a system for picking of mid-infrared and terahertz (THz) radiation pulses from the free-electron laser (FEL) FELBE operating at a repetition rate of 13 MHz. Single pulses are reflected by a dense electron-hole plasma in a Ge slab that is photoexcited by amplified near-infrared (NIR) laser systems operating at repetition rates of 1 kHz and 100 kHz, respectively. The peak intensity of picked pulses is up to 400 times larger than the peak intensity of residual pulses. The required NIR fluence for picking pulses at wavelengths in the range from 5 μm to 30 μm is discussed. In addition, we show that the reflectivity of the plasma decays on a time scale from 100 ps to 1 ns dependent on the wavelengths of the FEL and the NIR laser. The plasma switch enables experiments with the FEL that require high peak power but lower average power. Furthermore, the system is well suited to investigate processes with decay times in the μs to ms regime, i.e., much longer than the 77 ns long pulse repetition period of FELBE.

Single-pulse picking at kHz repetition rates using a Ge plasma switch at the free-electron laser FELBE

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

Schmidt, J., E-mail: j.schmidt@hzdr.de; Helm, M.; Technische Universität Dresden, 01062 Dresden

2015-06-15

We demonstrate a system for picking of mid-infrared and terahertz (THz) radiation pulses from the free-electron laser (FEL) FELBE operating at a repetition rate of 13 MHz. Single pulses are reflected by a dense electron-hole plasma in a Ge slab that is photoexcited by amplified near-infrared (NIR) laser systems operating at repetition rates of 1 kHz and 100 kHz, respectively. The peak intensity of picked pulses is up to 400 times larger than the peak intensity of residual pulses. The required NIR fluence for picking pulses at wavelengths in the range from 5 μm to 30 μm is discussed. Inmore » addition, we show that the reflectivity of the plasma decays on a time scale from 100 ps to 1 ns dependent on the wavelengths of the FEL and the NIR laser. The plasma switch enables experiments with the FEL that require high peak power but lower average power. Furthermore, the system is well suited to investigate processes with decay times in the μs to ms regime, i.e., much longer than the 77 ns long pulse repetition period of FELBE.« less

Using Unconstrained Tongue Motion as an Alternative Control Mechanism for Wheeled Mobility

PubMed Central

Huo, Xueliang; Ghovanloo, Maysam

2015-01-01

Tongue drive system (TDS) is a tongue-operated, minimally invasive, unobtrusive, noncontact, and wireless assistive technology that infers users’ intentions by detecting and classifying their voluntary tongue motions, and translating them to user-defined commands. We have developed customized interface circuitry between an external TDS (eTDS) prototype and a commercial powered wheelchair (PWC) as well as three control strategies to evaluate the tongue motion as an alternative control input for wheeled mobility. We tested the eTDS performance in driving PWCs on 12 able-bodied human subjects, of which 11 were novice. The results showed that all subjects could complete navigation tasks by operating the PWC using their tongue motions. Despite little prior experience, the average time using the eTDS and the tongue was only approximately three times longer than using a joystick and the fingers. Navigation time was strongly dependant on the number of issued commands, which reduced by gaining experience. Particularly, the unintended issued commands (the Midas touch problem) were rare, demonstrating the effectiveness of the tongue tracking and external magnetic field cancellation algorithms as well as the safety of the TDS for wheeled mobility. PMID:19362901

Using unconstrained tongue motion as an alternative control mechanism for wheeled mobility.

PubMed

Huo, Xueliang; Ghovanloo, Maysam

2009-06-01

Tongue drive system (TDS) is a tongue-operated, minimally invasive, unobtrusive, noncontact, and wireless assistive technology that infers users' intentions by detecting and classifying their voluntary tongue motions, and translating them to user-defined commands. We have developed customized interface circuitry between an external TDS (eTDS) prototype and a commercial powered wheelchair (PWC) as well as three control strategies to evaluate the tongue motion as an alternative control input for wheeled mobility. We tested the eTDS performance in driving PWCs on 12 able-bodied human subjects, of which 11 were novice. The results showed that all subjects could complete navigation tasks by operating the PWC using their tongue motions. Despite little prior experience, the average time using the eTDS and the tongue was only approximately three times longer than using a joystick and the fingers. Navigation time was strongly dependant on the number of issued commands, which reduced by gaining experience. Particularly, the unintended issued commands (the Midas touch problem) were rare, demonstrating the effectiveness of the tongue tracking and external magnetic field cancellation algorithms as well as the safety of the TDS for wheeled mobility.

Predicting Young’s Modulus of Glass/Ceramic Sealant for Solid Oxide Fuel Cell Considering the Combined Effects of Aging, Micro-Voids and Self-Healing

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

Liu, Wenning N.; Sun, Xin; Khaleel, Mohammad A.

We study the temperature dependent Young’s modulus for the glass/ceramic seal material used in Solid Oxide Fuel Cells (SOFCs). With longer heat treatment or aging time during operation, further devitrification may reduce the residual glass content in the seal material while boosting the ceramic crystalline content. In the meantime, micro-voids induced by the cooling process from the high operating temperature to room temperature can potentially degrade the mechanical properties of the glass/ceramic sealant. Upon reheating to the SOFC operating temperature, possible self-healing phenomenon may occur in the glass/ceramic sealant which can potentially restore some of its mechanical properties. A phenomenologicalmore » model is developed to model the temperature dependent Young’s modulus of glass/ceramic seal considering the combined effects of aging, micro-voids, and possible self-healing. An aging-time-dependent crystalline content model is first developed to describe the increase of the crystalline content due to the continuing devitrification under high operating temperature. A continuum damage mechanics (CDM) model is then adapted to model the effects of both cooling induced micro-voids and reheating induced self-healing. This model is applied to model the glass-ceramic G18, a candidate SOFC seal material previously developed at PNNL. Experimentally determined temperature dependent Young’s modulus is used to validate the model predictions« less

Segmentation and learning in the quantitative analysis of microscopy images

NASA Astrophysics Data System (ADS)

Ruggiero, Christy; Ross, Amy; Porter, Reid

2015-02-01

In material science and bio-medical domains the quantity and quality of microscopy images is rapidly increasing and there is a great need to automatically detect, delineate and quantify particles, grains, cells, neurons and other functional "objects" within these images. These are challenging problems for image processing because of the variability in object appearance that inevitably arises in real world image acquisition and analysis. One of the most promising (and practical) ways to address these challenges is interactive image segmentation. These algorithms are designed to incorporate input from a human operator to tailor the segmentation method to the image at hand. Interactive image segmentation is now a key tool in a wide range of applications in microscopy and elsewhere. Historically, interactive image segmentation algorithms have tailored segmentation on an image-by-image basis, and information derived from operator input is not transferred between images. But recently there has been increasing interest to use machine learning in segmentation to provide interactive tools that accumulate and learn from the operator input over longer periods of time. These new learning algorithms reduce the need for operator input over time, and can potentially provide a more dynamic balance between customization and automation for different applications. This paper reviews the state of the art in this area, provides a unified view of these algorithms, and compares the segmentation performance of various design choices.

Georgia Tech Studies of Sub-Critical Advanced Burner Reactors with a D-T Fusion Tokamak Neutron Source for the Transmutation of Spent Nuclear Fuel

NASA Astrophysics Data System (ADS)

Stacey, W. M.

2009-09-01

The possibility that a tokamak D-T fusion neutron source, based on ITER physics and technology, could be used to drive sub-critical, fast-spectrum nuclear reactors fueled with the transuranics (TRU) in spent nuclear fuel discharged from conventional nuclear reactors has been investigated at Georgia Tech in a series of studies which are summarized in this paper. It is found that sub-critical operation of such fast transmutation reactors is advantageous in allowing longer fuel residence time, hence greater TRU burnup between fuel reprocessing stages, and in allowing higher TRU loading without compromising safety, relative to what could be achieved in a similar critical transmutation reactor. The required plasma and fusion technology operating parameter range of the fusion neutron source is generally within the anticipated operational range of ITER. The implications of these results for fusion development policy, if they hold up under more extensive and detailed analysis, is that a D-T fusion tokamak neutron source for a sub-critical transmutation reactor, built on the basis of the ITER operating experience, could possibly be a logical next step after ITER on the path to fusion electrical power reactors. At the same time, such an application would allow fusion to contribute to meeting the nation's energy needs at an earlier stage by helping to close the fission reactor nuclear fuel cycle.

Impact of long farm working hours on child safety practices in agricultural settings.

PubMed

Marlenga, Barbara; Pahwa, Punam; Hagel, Louise; Dosman, James; Pickett, William; Brison, Robert J; Crowe, Trever; Koehncke, Niels; Snodgrass, Phyllis; Day, Lesley; Voaklander, Donald

2010-01-01

To characterize working hours of adult farm owner-operators and their spouses by season, and to examine associations between working hours and farm safety practices affecting children. We conducted a secondary analysis of cross-sectional survey data collected as part of an existing study of injury and its determinants. Owner-operators reported a median of 60 to 70 hours of farm work per week during warm weather months, with declines in hours over the winter. Spouses reported similar seasonal patterns, although their median reported hours were much lower. Longer farm working hours by owner-operators were marginally associated with increased exposure of teenagers to farm work hazards. Exposures of young children to worksite hazards rose in association with longer farm working hours by spouses. Exposures of children to farm worksite hazards and demands may be consequences of adult long working hours. © 2010 National Rural Health Association.

A versatile valving toolkit for automating fluidic operations in paper microfluidic devices.

PubMed

Toley, Bhushan J; Wang, Jessica A; Gupta, Mayuri; Buser, Joshua R; Lafleur, Lisa K; Lutz, Barry R; Fu, Elain; Yager, Paul

2015-03-21

Failure to utilize valving and automation techniques has restricted the complexity of fluidic operations that can be performed in paper microfluidic devices. We developed a toolkit of paper microfluidic valves and methods for automatic valve actuation using movable paper strips and fluid-triggered expanding elements. To the best of our knowledge, this is the first functional demonstration of this valving strategy in paper microfluidics. After introduction of fluids on devices, valves can actuate automatically after a) a certain period of time, or b) the passage of a certain volume of fluid. Timing of valve actuation can be tuned with greater than 8.5% accuracy by changing lengths of timing wicks, and we present timed on-valves, off-valves, and diversion (channel-switching) valves. The actuators require ~30 μl fluid to actuate and the time required to switch from one state to another ranges from ~5 s for short to ~50 s for longer wicks. For volume-metered actuation, the size of a metering pad can be adjusted to tune actuation volume, and we present two methods - both methods can achieve greater than 9% accuracy. Finally, we demonstrate the use of these valves in a device that conducts a multi-step assay for the detection of the malaria protein PfHRP2. Although slightly more complex than devices that do not have moving parts, this valving and automation toolkit considerably expands the capabilities of paper microfluidic devices. Components of this toolkit can be used to conduct arbitrarily complex, multi-step fluidic operations on paper-based devices, as demonstrated in the malaria assay device.

A versatile valving toolkit for automating fluidic operations in paper microfluidic devices

PubMed Central

Toley, Bhushan J.; Wang, Jessica A.; Gupta, Mayuri; Buser, Joshua R.; Lafleur, Lisa K.; Lutz, Barry R.; Fu, Elain; Yager, Paul

2015-01-01

Failure to utilize valving and automation techniques has restricted the complexity of fluidic operations that can be performed in paper microfluidic devices. We developed a toolkit of paper microfluidic valves and methods for automatic valve actuation using movable paper strips and fluid-triggered expanding elements. To the best of our knowledge, this is the first functional demonstration of this valving strategy in paper microfluidics. After introduction of fluids on devices, valves can actuate automatically a) after a certain period of time, or b) after the passage of a certain volume of fluid. Timing of valve actuation can be tuned with greater than 8.5% accuracy by changing lengths of timing wicks, and we present timed on-valves, off-valves, and diversion (channel-switching) valves. The actuators require ~30 μl fluid to actuate and the time required to switch from one state to another ranges from ~5 s for short to ~50s for longer wicks. For volume-metered actuation, the size of a metering pad can be adjusted to tune actuation volume, and we present two methods – both methods can achieve greater than 9% accuracy. Finally, we demonstrate the use of these valves in a device that conducts a multi-step assay for the detection of the malaria protein PfHRP2. Although slightly more complex than devices that do not have moving parts, this valving and automation toolkit considerably expands the capabilities of paper microfluidic devices. Components of this toolkit can be used to conduct arbitrarily complex, multi-step fluidic operations on paper-based devices, as demonstrated in the malaria assay device. PMID:25606810

A Comparison of Outcomes Following Laparoscopic and Open Hysterectomy With or Without Lymphadenectomy for Presumed Early-Stage Endometrial Cancer: Results From the Medical Research Council ASTEC Trial.

PubMed

Kyrgiou, Maria; Swart, Anne-Marie; Qian, Wendi; Warwick, Jane

2015-10-01

Laparoscopic hysterectomy (LH) is increasingly used for the management of endometrial malignancy. Its benefits may be particularly pronounced as these women are more likely to be older or obese. The aim of this study was to determine whether outcomes for LH are comparable to the open hysterectomy (OH). This was a prospective cohort study nested within the multicenter ASTEC (A Study in the Treatment of Endometrial Cancer) randomized controlled trial (1998-2005). Women with presumed early endometrial cancer were included. Laparoscopic hysterectomy was compared with OH with or without systematic lymphadenectomy. Overall survival, time to first recurrence, complication rates, and surgical outcomes were the main outcome measures. Of 1408 women, 1309 (93%) received OH, and 99 (7%) had LH. LH was associated with longer operating time (median, LH 105 minutes [interquartile range (IQR), 60-150] vs OH 80 minutes [IQR, 60-95]; P < 0.001) but 50% shorter hospital stay (median, LH 4 days [IQR, 3-5] vs OH 6 days [IQR, 5-7]). The number of harvested lymph nodes was similar (median, LH 13 [IQR, 10-16] vs OH 12 [IQR, 11-13]; P = 0.67). LH had fewer intraoperative and postoperative adverse events (9% difference, LH 21% vs OH 30%; borderline significance; P = 0.07). The rate of conversion to laparotomy for the LH group was high (27%). The median follow-up was 37 months. After adjusting for significant prognostic factors, the hazard ratio for overall survival in those who underwent LH compared with those who underwent OH was 0.67 (95% confidence interval, 0.31-1.43) (P = 0.30). Laparoscopic hysterectomy for early endometrial cancer is safe. Although it requires longer operating time it is associated with shorter hospital stay and favorable morbidity profile. Further studies are required to assess the long-term safety.

[Use of four kinds of three-dimensional printing guide plate in bone tumor resection and reconstruction operation].

PubMed

Fu, Jun; Guo, Zheng; Wang, Zhen; Li, Xiangdong; Fan, Hongbin; Li, Jing; Pei, Yanjun; Pei, Guoxian; Li, Dan

2014-03-01

To explore the effectiveness of excision and reconstruction of bone tumor by using operation guide plate made by variety of three-dimensional (3-D) printing techniques, and to compare the advantages and disadvantages of different 3-D printing techniques in the manufacture and application of operation guide plate. Between September 2012 and January 2014, 31 patients with bone tumor underwent excision and reconstruction of bone tumor by using operation guide plate. There were 19 males and 12 females, aged 6-67 years (median, 23 years). The disease duration ranged from 15 days to 12 months (median, 2 months). There were 13 cases of malignant tumor and 18 cases of benign tumor. The tumor located in the femur (9 cases), the spine (7 cases), the tibia (6 cases), the pelvis (5 cases), the humerus (3 cases), and the fibula (1 case). Four kinds of 3-D printing technique were used in processing operation guide plate: fused deposition modeling (FDM) in 9 cases, stereo lithography appearance (SLA) in 14 cases, 3-D printing technique in 5 cases, and selective laser sintering (SLS) in 3 cases; the materials included ABS resin, photosensitive resin, plaster, and aluminum alloy, respectively. Before operation, all patients underwent thin layer CT scanning (0.625 mm) in addition to conventional imaging. The data were collected for tumor resection design, and operation guide plate was designed on the basis of excision plan. Preoperatively, the operation guide plates were made by 3-D printing equipment. After sterilization, the guide plates were used for excision and reconstruction of bone tumor. The time of plates processing cycle was recorded to analyse the efficiency of 4 kinds of 3-D printing techniques. The time for design and operation and intraoperative fluoroscopy frequency were recorded. Twenty-eight patients underwent similar operations during the same period as the control group. The processing time of operation guide plate was (19.3 +/- 6.5) hours in FDM, (5.2 +/- 1.3) hours in SLA, (8.6 +/- 1.9) hours in 3-D printing technique, and (51.7 +/- 12.9) hours in SLS. The preoperative design and operation guide plate were successfully made, which was used for excision and reconstruction of bone tumor in 31 cases. Except 3 failures (operation guide plate fracture), the resection and reconstruction operations followed the preoperative design in the other 28 cases. The patients had longer design time, shorter operation time, and less fluoroscopy frequency than the patients of the control group, showing significant differences (P < 0.05). The follow-up time was 1-12 months (mean, 3.7 months). Postoperative X-ray and CT showed complete tumor resection and stable reconstruction. 3-D printing operation guide plates are well adapted to the requirements of individual operation for bone tumor resection and reconstruction. The 4 kinds of 3-D printing techniques have their own advantages and should be chosen according to the need of operation.

Crew Factors in Flight Operations 7: Psychophysiological Responses to Overnight Cargo Operations

NASA Technical Reports Server (NTRS)

Gander, Philippa H.; Gregory, Kevin B.; Connell, Linda J.; Miller, Donna L.; Graeber, R. Curtis; Rosekind, Mark R.

1996-01-01

To document the psychophysiological effects of flying overnight cargo operations, 41 B-727 crew members (average age 38 yr) were monitored before, during, and after one of two typical 8-day trip patterns. During daytime layovers, the average sleep episode was 3 hr (41%) shorter than nighttime sleeps and was rated as lighter, less restorative, and poorer overall. Sleep was frequently split into several episodes and totaled 1.2 hr less per 24 hr than on pretrip days. Each trip pattern included a night off, which was an effective countermeasure against the accumulating sleep debt. The organization of sleep during daytime layovers reflected the interaction of duty timing with circadian physiology. The circadian temperature rhythm did not adapt completely to the inverted wake-rest schedule on duty days, being delayed by about 3 hr. Highest subjective fatigue and lowest activation occurred around the time of the temperature minimum. On duty days, reports of headaches increased by 400%, of congested nose by 200%, and of burning eyes by 900%. Crew members also reported eating more snacks. Compared with daytime short-haul air-transport operations, the overnight cargo trips included fewer duty and flight hours, and had longer layovers. Overnight cargo crews also averaged 5.4 yr younger than their daytime short-haul counterparts. On trips, both groups lost a comparable amount of sleep per 24 hr, but the overnight cargo crews had shorter individual sleep episodes and more broken sleep. These data clearly demonstrate that overnight cargo operations, like other night work, involve physiological disruption not found in comparable daytime operations.

Factors associated with sealant outcome in 2 pediatric dental clinics: a multivariate hierarchical analysis.

PubMed

West, Nathan G; Ilief-Ala, Melina A; Douglass, Joanna M; Hagadorn, James I

2011-01-01

This study's purpose was to determine whether one-time sealants placed by pediatric dental residents vs dental students have different outcomes. The effect of isolation technique, behavior, duration of follow-up, and caries history was also examined. Records from 2 inner-city pediatric dental clinics were audited for 6- to 10-year-old patients with a permanent first molar sealant with at least 2 years of follow-up. A successful sealant was a one-time sealant that received no further treatment and was sealed or unsealed but not carious or restored at the final audit. Charts from 203 children with 481 sealants were audited. Of these, 281 sealants were failures. Univariate analysis revealed longer follow-up and younger age were associated with sealant failure. Operator type, child behavior, and isolation technique were not associated with sealant failure. After adjusting for follow-up duration, increased age at treatment reduced the odds of sealant failure while a history of caries reduced the protective effect of increased age. After adjusting for these factors, practitioner type, behavior, and type of isolation were not associated with sealant outcome in multivariate analysis. Age at sealant placement, history of caries prior to placement, and longer duration of follow-up are associated with sealant failure.

Effects of injection parameters, boost, and swirl ratio on gasoline compression ignition operation at idle and low-load conditions

DOE PAGES

Kodavasal, Janardhan; Kolodziej, Christopher P.; Ciatti, Stephen A.; ...

2016-11-03

In this study, we study the effects of injector nozzle inclusion angle, injection pressure, boost, and swirl ratio on gasoline compression ignition combustion. Closed-cycle computational fluid dynamics simulations using a 1/7th sector mesh representing a single cylinder of a four-cylinder 1.9 L diesel engine, operated in gasoline compression ignition mode with 87 anti-knock index (AKI) gasoline, were performed. Two different operating conditions were studied—the first is representative of idle operation (4 mg fuel/cylinder/cycle, 850 r/min), and the second is representative of a low-load condition (10 mg fuel/cylinder/cycle, 1500 r/min). The mixture preparation and reaction space from the simulations were analyzedmore » to gain insights into the effects of injection pressure, nozzle inclusion angle, boost, and swirl ratio on achieving stable low-load to idle gasoline compression ignition operation. It was found that narrower nozzle inclusion angles allow for more reactivity or propensity to ignition (determined qualitatively by computing constant volume ignition delays) and are suitable over a wider range of injection timings. Under idle conditions, it was found that lower injection pressures helped to reduce overmixing of the fuel, resulting in greater reactivity and ignitability (ease with which ignition can be achieved) of the gasoline. However, under the low-load condition, lower injection pressures did not increase ignitability, and it is hypothesized that this is because of reduced chemical residence time resulting from longer injection durations. Reduced swirl was found to maintain higher in-cylinder temperatures through compression, resulting in better ignitability. It was found that boosting the charge also helped to increase reactivity and advanced ignition timing.« less

Visual-perceptual mismatch in robotic surgery.

PubMed

Abiri, Ahmad; Tao, Anna; LaRocca, Meg; Guan, Xingmin; Askari, Syed J; Bisley, James W; Dutson, Erik P; Grundfest, Warren S

2017-08-01

The principal objective of the experiment was to analyze the effects of the clutch operation of robotic surgical systems on the performance of the operator. The relative coordinate system introduced by the clutch operation can introduce a visual-perceptual mismatch which can potentially have negative impact on a surgeon's performance. We also assess the impact of the introduction of additional tactile sensory information on reducing the impact of visual-perceptual mismatch on the performance of the operator. We asked 45 novice subjects to complete peg transfers using the da Vinci IS 1200 system with grasper-mounted, normal force sensors. The task involves picking up a peg with one of the robotic arms, passing it to the other arm, and then placing it on the opposite side of the view. Subjects were divided into three groups: aligned group (no mismatch), the misaligned group (10 cm z axis mismatch), and the haptics-misaligned group (haptic feedback and z axis mismatch). Each subject performed the task five times, during which the grip force, time of completion, and number of faults were recorded. Compared to the subjects that performed the tasks using a properly aligned controller/arm configuration, subjects with a single-axis misalignment showed significantly more peg drops (p = 0.011) and longer time to completion (p < 0.001). Additionally, it was observed that addition of tactile feedback helps reduce the negative effects of visual-perceptual mismatch in some cases. Grip force data recorded from grasper-mounted sensors showed no difference between the different groups. The visual-perceptual mismatch created by the misalignment of the robotic controls relative to the robotic arms has a negative impact on the operator of a robotic surgical system. Introduction of other sensory information and haptic feedback systems can help in potentially reducing this effect.

Effects of injection parameters, boost, and swirl ratio on gasoline compression ignition operation at idle and low-load conditions

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

Kodavasal, Janardhan; Kolodziej, Christopher P.; Ciatti, Stephen A.

In this study, we study the effects of injector nozzle inclusion angle, injection pressure, boost, and swirl ratio on gasoline compression ignition combustion. Closed-cycle computational fluid dynamics simulations using a 1/7th sector mesh representing a single cylinder of a four-cylinder 1.9 L diesel engine, operated in gasoline compression ignition mode with 87 anti-knock index (AKI) gasoline, were performed. Two different operating conditions were studied—the first is representative of idle operation (4 mg fuel/cylinder/cycle, 850 r/min), and the second is representative of a low-load condition (10 mg fuel/cylinder/cycle, 1500 r/min). The mixture preparation and reaction space from the simulations were analyzedmore » to gain insights into the effects of injection pressure, nozzle inclusion angle, boost, and swirl ratio on achieving stable low-load to idle gasoline compression ignition operation. It was found that narrower nozzle inclusion angles allow for more reactivity or propensity to ignition (determined qualitatively by computing constant volume ignition delays) and are suitable over a wider range of injection timings. Under idle conditions, it was found that lower injection pressures helped to reduce overmixing of the fuel, resulting in greater reactivity and ignitability (ease with which ignition can be achieved) of the gasoline. However, under the low-load condition, lower injection pressures did not increase ignitability, and it is hypothesized that this is because of reduced chemical residence time resulting from longer injection durations. Reduced swirl was found to maintain higher in-cylinder temperatures through compression, resulting in better ignitability. It was found that boosting the charge also helped to increase reactivity and advanced ignition timing.« less

Initial brazilian experience in the treatment of localized prostate cancer using a new generation cryotechnology: feasibility study.

PubMed

Kim, Fernando J; Cerqueira, Michael A; Almeida, Jose C; Pompeo, Alexandre; Sehrt, David; Calheiros, Jose M; Martins, Fernando A; Molina, Wilson R

2012-01-01

The objective of our study is to present the first Brazilian cryoablation experience in the treatment of low and intermediate risk localized prostate cancer using 3rd generation cryoablation and real-time biplanar transrectal ultrasonography. Ten Brazilian patients underwent primary cryoablation for localized prostate cancer between October 2010 and June 2011. All patients consented for whole gland primary cryotherapy. The procedures were performed by 3rd generation cryoablation with the Cryocare System ® (Endocare, Irvine, California). Preoperative data collection included patient demographics along with prostate gland size, Gleason score, serum prostate specific antigen, and erectile function status. Operative and post--operative assessment involved estimated blood loss, operative time, complications, serum PSA level, erectile function status, urinary incontinence, biochemical disease free survival (BDFS), and follow-up time. All patients in the study successfully underwent whole gland cryoablation. The mean of: age, prostate size, PSA level, and Gleason score, was 66.2 years old; 40.7 g; 7.8 ng/mL; and 6 respectively. All patients were classified as low or moderate D' Amico risk (5 low and 5 moderate). Erectile dysfunction was present in 50% of patients. The estimated blood loss was minimal, operative time was 46.1 minutes. All patients that developed erectile dysfunction post-treatment responded to oral or intracavernosal medications with early penile rehabilitation. All patients maintained urinary continence by the end of a 10 months evaluation period and none had biochemical relapse within the mean follow-up of 13 months (7-15 months). Our initial experience shows that cryoablation is a minimally invasive option for the treatment of localized prostate cancer. Short term data seems to be promising but longer follow-up is necessary to verify oncological and functional results.

Improving Minimally Invasive Adrenalectomy: Selection of Optimal Approach and Comparison of Outcomes.

PubMed

Lairmore, Terry C; Folek, Jessica; Govednik, Cara M; Snyder, Samuel K

2016-07-01

Minimally invasive adrenalectomy is commonly performed by either a transperitoneal laparoscopic (TLA) or posterior retroperitoneoscopic (PRA) approach. Our group described the technique for robot-assisted PRA (RAPRA) in 2010. Few studies are available that directly compare outcomes between the available operative approaches. We reviewed our results for minimally invasive adrenalectomy using the three different approaches over a 10-year period. Between January 2005 and April 2015, 160 minimally invasive adrenalectomies were performed. Clinicopathologic data were prospectively collected and retrospectively analyzed. The primary endpoints evaluated were operative time, blood loss, length of stay (LOS), and morbidity. The study included 67 TLA, 76 PRA, and 17 RAPRA procedures. Tumor size for PRA/RAPRA was smaller than for patients undergoing TLA (2.38 vs 3.6 cm, p ≤ 0.0001). Procedure time was shorter for PRA versus TLA (133.3 vs 152.8 min, p = 0.0381), as was LOS (1.85 vs 2.82 days, p = 0.0145). Procedure time was longer in RAPRA versus TLA/PRA (177 vs 153/133 min, p = 0.008), but LOS was significantly decreased (1.53 vs 2.82/1.85 days, p = 0.004). Minimally invasive adrenalectomy is associated with expected excellent outcomes regardless of approach. In our series, the posterior approach is associated with decreased operative time and LOS. Robotic technology provides potential advantages for the surgeon at the expense of more complex setup requirements and costs. Further study is required to demonstrate clear benefit of one surgical approach. Utilization of the entire spectrum of available operative techniques can allow for selection of the optimal approach based on individual patient factors.

Right anterior mini-thoracotomy vs. conventional sternotomy for aortic valve replacement: a propensity-matched comparison

PubMed Central

Del Giglio, Mauro; Mikus, Elisa; Micari, Antonio; Calvi, Simone; Tripodi, Alberto; Campo, Gianluca; Maietti, Elisa; Castriota, Fausto; Cremonesi, Alberto

2018-01-01

Background Right anterior mini-thoracotomy (MIAVR) is a promising technique for aortic valve replacement. We aimed at comparing its outcomes with those obtained in a propensity-matched group of patients undergoing sternotomy at our two high-volume centers. Methods Main clinical and operative data of patients undergoing aortic valve replacement between January 2010 and May 2016 were retrospectively collected. A total of 678 patients were treated with a standard full sternotomy approach, while MIAVR was performed in 502. Propensity score matching identified 363 patients per each group. Results In-hospital mortality was not significantly different between the propensity-matched groups (1.7% in MIAVR patients vs. 2.2% in conventional sternotomy patients; P=0.79). No significant difference in the incidence of major post-operative complications was observed. Post-operative ventilation times (median 7, range 5–12 hours in MIAVR patients vs. median 7, range 5–12 in conventional sternotomy patients; P=0.72) were not significantly different between the two groups. Cardiopulmonary bypass time (61.0±21.0 vs. 65.9±24.7 min in conventional sternotomy group; P<0.01) and aortic cross-clamping time (48.3±16.7 vs. 53.2±19.6 min in full sternotomy group; P<0.01) were shorter in MIAVR group. EuroSCORE (OR 1.52, 95% CI, 1.12–2.06; P<0.01) was found to be the only independent predictor of intra-hospital mortality in the whole propensity-matched population. Conclusions Our experience shows that mini-access isolated aortic valve surgery is a reproducible, safe and effective procedure with similar outcomes and no longer operative times compared to conventional sternotomy. PMID:29707310

Outcomes of flexible ureterorenoscopy and laser fragmentation for renal stones: comparison between digital and conventional ureteroscope.

PubMed

Somani, Bhaskar K; Al-Qahtani, Saeed M; de Medina, Sixtina Diez Gil; Traxer, Olivier

2013-11-01

To compare the outcomes of flexible ureterorenoscopy and lasertripsy (FURS) using digital and conventional FURS for kidney stones. From September 2007 to April 2011, 118 patients underwent FURS (by the same surgeon). The outcomes were compared between equal numbers of procedures (59 each) using a conventional flexible ureterorenoscope (C-FURS; Olympus URF-P5) and a digital flexible ureterorenoscope (D-FURS; Olympus URF-V). Although the deflection, working channel, and field view are similar in both, the initial and terminal diameter is 8.4F and 9.9F and 6.9F and 8.4F for the D-FURS and C-FURS, respectively. The mean stone fragmentation time was calculated by the size per operative time. The preoperative, operative, and postoperative data were retrospectively analyzed and compared. The patient demographics were comparable. The mean stone size was 12.8 and 12 mm in the C-FURS and D-FURS groups, respectively. The initial assessment of the entire pyelocaliceal system was possible in 58 of 59 cases (98%) in the C-FURS group and 56 of 59 cases (94%) in the D-FURS group. The mean operative time was significantly longer in the C-FURS group (53.8 ± 15.2 minutes vs 44.5 ± 14.9 minutes). The overall stone-free rate 1 month after the procedure was 86% in the C-FURS group and 88% in the D-FURS group. Although on comparison, the D-FURS had slightly limited maneuverability, comparable success rates can be achieved with both conventional and digital ureteroscopes. D-FURSs significantly reduced the operative time compared with C-FURSs. Copyright © 2013 Elsevier Inc. All rights reserved.

Anomalous dielectric relaxation with linear reaction dynamics in space-dependent force fields.

PubMed

Hong, Tao; Tang, Zhengming; Zhu, Huacheng

2016-12-28

The anomalous dielectric relaxation of disordered reaction with linear reaction dynamics is studied via the continuous time random walk model in the presence of space-dependent electric field. Two kinds of modified reaction-subdiffusion equations are derived for different linear reaction processes by the master equation, including the instantaneous annihilation reaction and the noninstantaneous annihilation reaction. If a constant proportion of walkers is added or removed instantaneously at the end of each step, there will be a modified reaction-subdiffusion equation with a fractional order temporal derivative operating on both the standard diffusion term and a linear reaction kinetics term. If the walkers are added or removed at a constant per capita rate during the waiting time between steps, there will be a standard linear reaction kinetics term but a fractional order temporal derivative operating on an anomalous diffusion term. The dielectric polarization is analyzed based on the Legendre polynomials and the dielectric properties of both reactions can be expressed by the effective rotational diffusion function and component concentration function, which is similar to the standard reaction-diffusion process. The results show that the effective permittivity can be used to describe the dielectric properties in these reactions if the chemical reaction time is much longer than the relaxation time.

42 CFR 424.530 - Denial of enrollment in the Medicare program.

Code of Federal Regulations, 2010 CFR

2010-10-01

... enrollment application to the type of provider or supplier enrolling, and has not submitted a plan of... the provider or supplier is not operational, or is not meeting Medicare enrollment requirements to... A provider is no longer operational to furnish Medicare covered items or services, or the provider...

NOAA Office of Exploration and Research > Data Access > Operational Data

Science.gov Websites

Management Saturday, May 26, 2018 THIS WEBSITE IS NO LONGER BEING UPDATED OR MAINTAINED. FOR CURRENT INFORMATION ON THE NOAA OFFICE OF OCEAN EXPLORATION AND RESEARCH, VISIT: OCEANEXPLORER.NOAA.GOV Technology Initiatives Science Overview Data Access Overview Operational Data Management Publications

12 CFR 950.5 - Terms and conditions for advances.

Code of Federal Regulations, 2010 CFR

2010-01-01

... advances. (3) Exceptions. The advance pricing policies contained in paragraph (b)(1) of this section shall... longer maturities consistent with the safe and sound operation of the Bank. (b) Advance pricing—(1... administrative and operating costs associated with making such advances to members. (2) Differential pricing. (i...

75 FR 55475 - Drawbridge Operation Regulation; Pequonnock River, Bridgeport, CT

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-13

... two bridges because the draw spans of the bridges have been removed. DATES: This rule is effective... removing the operation regulations for two moveable draw bridges that no longer have moveable spans. Under... litigation, eliminate ambiguity, and reduce burden. Protection of Children We have analyzed this rule under...

Thermal modeling of a Ni-H2 battery cell

NASA Technical Reports Server (NTRS)

Ryu, Si-Ok; Dewitt, K. J.; Keith, T. G.

1991-01-01

The nickel-hydrogen secondary battery has many desirable features which make it attractive for satellite power systems. It can provide a significant improvement over the energy density of present spacecraft nickel-cadnium batteries, combined with longer life, tolerance to overcharge and possibility of state-of-charge indication. However, to realize these advantages, accurate thermal modeling of nickel-hydrogen cells is required in order to properly design the battery pack so that it operates within a specified temperature range during the operation. Maintenance of a low operating temperature and a uniform temperature profile within the cell will yield better reliability, improved cycle life and better charge/discharge efficiencies. This research has the objective of developing and testing a thermal model which can be used to characterize battery operation. Primarily, temperature distribution with the heat generation rates as a function of position and time will be evaluated for a Ni-H2 cell in the three operating modes: (1) charge cycle, (2) discharge cycle, and (3) overcharge condition, if applicable. Variables to be examined include charging current, discharge rates, state of charge, pressure and temperature. Once the thermal model has been developed, this resulting model will predict the actual operating temperature and temperature gradient for the specific cell geometry to be used.

[Comparative study on laparoscopic vaginoplasty using pedicled ileal and sigmoid colon segment transfer].

PubMed

Zhang, Dawei; Zhang, Jun; Wang, Huanying; Li, Bin; Zhu, Xiaoxing; Wang, Liying; Wu, Jixiang

2014-03-01

To study the clinical effect of laparoscopic vaginoplasty using pedicled ileal and sigmoid colon segment. From January 2004 to December 2009, 105 cases undergoing laparoscope-assisted vaginoplasty using a vascularized pedicled intestinal flap were studied retrospectively. Operation time, blood loss in operating, bowel movement after operation, postoperation hospital duration, side effect, and artificial vagina were compared between two surgical management. The vaginoplasty were preformed successfully in all 105 cases. There were 48 patients treated by aparoscope-assisted ileal vaginoplasty and 57 patients treated by laparoscope-assisted sigmoid colon vaginoplasty. The values of the operation time [(141 ± 22) minutes versus (159 ± 18) minutes, P = 0.000], blood loss in operating [(42 ± 6) ml versus (83 ± 14) ml, P = 0.000], bowel movement after operation (36 ± 9) hours versus (68 ± 8) hours(P = 0.000), and postoperation hospital duration [(9.8 ± 2.0) days versus (11.1 ± 1.3) days, P = 0.004] in the sigmoid colon vaginoplasty group were longer or higher than those in ileal vaginoplasty group (P < 0.05).No intraoprative complication occurred. There were four postoperative complications: 2 cases with intestinal obstruction in sigmoid colon vaginoplasty group, 1 case with urethral orifice stenosis and 1 case with vaginal-rectal fistula in ileal vaginoplasty group. At follow-up of 6-62 months, all artificial vaginas had a capacity of over two fingers in wideness and 12-15 cm in length. Vaginal discharges resembled a milky white water or mucus without odour. Fifty-five patients with sexual intercourse reported satisfactory results.Six patients complained vaginal stenosis:5 patients in ileal vaginoplasty group and 1 patient in sigmoid colon vaginoplasty group. Laparoscope-assisted vaginoplasty using pedicled ileum or sigmoid colon segment are both the effective ways in forming vagina. The latter management takes more time and blood loss while operating, yet the incidence of vaginal opening contracture appeared to be decreasing trend.

11 Years of experience in vitreoretinal surgery training in Nairobi, Kenya, from 2000 to 2010.

PubMed

Schönfeld, Carl-Ludwig; Kollmann, Martin; Nyaga, Patrick; Onyango, Oskar; Klauss, Volker; Kampik, Anselm

2013-08-01

We aim to demonstrate that vitreoretinal surgery can be established in Nairobi, Kenya, by intermittent short visits of experienced surgeons combined with clinical/surgical observerships over a longer period of cooperation. This strategy might be a model for other developing countries. Time series over 11 years. 685 operations were performed over 11 years. After the 1998 al-Qaeda bomb assault on the U.S. embassy in Nairobi, Kenya, the Ludwig-Maximilians-University München (Germany) provided materials for surgery of 42 victims with eye injuries. From the year 2000 onward, this equipment has been used to establish a training unit at the Kenyatta Hospital in Nairobi. In 1 annual "project week," 1 author (C-L.S.) performed vitreoretinal surgery at the University of Nairobi in cooperation with the Kenyatta National Hospital and supervised resident eye surgeons. After 7 years of training in Nairobi, clinical/surgical observerships of vitreoretinal surgeons and operating theatre staff were commenced in Munich by 4- to 12-week visits. The project week in Nairobi was carried on. Number, indications, operating surgeons, kind, difficulty, duration of operations, and preparation were recorded and evaluated. The percentage of operations by resident surgeons increased from 29% (in 2000) via 80% (in 2009) to 73% (in 2010) with a partial failure of the laser device. The learning curve of local surgeons is also reflected by an increase of the operations' difficulty with only a moderate increase in operation time and marked decrease of preparation time. A vitreoretinal unit has been established in Nairobi using our training model. This unit has the potential to train colleagues from other sub-Saharan countries. This strategy has advantages over long-term aid deployment of foreign physicians such as avoiding financial burden for the surgeons to be trained and improving the home facility, but it requires commitment for long-term cooperation. Copyright © 2013 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.

Discharge stabilization studies of CO laser gas mixtures in quasi-steady supersonic flow

NASA Technical Reports Server (NTRS)

Srinivasan, G.; Smith, J. A.

1976-01-01

Experiments were conducted to study the applicability of a double discharge stabilization scheme in conditions appropriate for high energy CO lasers in supersonic flows. A Ludwieg tube impulse flow facility and a ballasted capacitor bank provided essentially steady flow and discharge conditions (d.c.) for times longer than ten electrode length-flow transit times. Steady, arc-free, volume discharges were produced in a Mach 3 test cavity using an auxiliary discharge to stabilize the main discharge in N2 and He/CO mixture. A signigicant result is the lack of observed plasma E/N changes in response to auxiliary discharge current changes. Also, where glow discharges were obtained, the energy loading achieved was very much less than the threshold level required for laser operation.