EOS: A project to investigate the design and construction of real-time distributed embedded operating systems

The EOS project is investigating the design and construction of a family of real-time distributed embedded operating systems for reliable, distributed aerospace applications. Using the real-time programming techniques developed in co-operation with NASA in earlier research, the project staff is building a kernel for a multiple processor networked system. The first six months of the grant included a study of scheduling in an object-oriented system, the design philosophy of the kernel, and the architectural overview of the operating system. In this report, the operating system and kernel concepts are described. An environment for the experiments has been built and several of the key concepts of the system have been prototyped. The kernel and operating system is intended to support future experimental studies in multiprocessing, load-balancing, routing, software fault-tolerance, distributed data base design, and real-time processing

In-line filter included into the syringe infusion pump assembly reduces flow irregularities

Purpose: To evaluate whether an in-line filter inserted in the syringe pump infusion line assembly influences start-up times and flow irregularities during vertical pump displacement at low infusion rates. Methods: Fluid delivery after syringe pump start-up and after vertical displacement of the syringe pump by −50cm was determined gravimetrically at flow rates of 0.5, 1.0 and 2.0mlh−1. Measurements were repeated for each flow rate four times with two different syringe pumps with and without an in-line filter incorporated. Data are shown as median and range. Results: Start-up times were reduced by an in-line filter at 0.5mlh−1 flow rate from 355.5s (0-660) to 115s (0-320), whereas the effect was attenuated at higher flow rates. Pooling of fluid into the infusion system after lowering the infusion syringe pump was halved in all flow rates tested. Amount of infusion bolus after elevating the syringe pump by 50cm was not affected by an in-line filter. Conclusion: In the evaluated model in-line filters help to reduce flow irregularities and delay in drug delivery of syringe pumps at low flow rates and represent an option to optimize continuous administration of highly concentrated short-acting drugs at very small infusion rate

Impact of weekday surgery on application of enhanced recovery pathway: a retrospective cohort study.

To compare the enhanced recovery after surgery (ERAS) protocol compliance and clinical outcomes depending on the weekday of surgery. Cohort of consecutive non-selected patients undergoing elective colorectal surgery from January 2012 to March 2015. This retrospective analysis of our prospective database compared patients operated early in the week (Monday and Tuesday) with patients operated in the second half (late: Thursday, Friday). Compliance with the ERAS protocol, functional recovery, complications and length of stay. Demographic and surgical details were similar between the early (n=352) and late groups (n=204). Overall compliance with the ERAS protocol was 78% vs 76% for the early and late groups, respectively (p=0.009). Significant differences were notably prolonged urinary drainage and intravenous fluid infusion in the late group. Complication rates and length of stay, however, were not different between surgery on Monday or Tuesday and surgery on Thursday or Friday. Application of the ERAS protocol showed only minor differences for patients operated on early or late during the week, and clinical outcomes were similar. A fully implemented ERAS programme appears to work also over the weekend

Preoperative Nutritional Conditioning of Crohn's Patients-Systematic Review of Current Evidence and Practice.

Crohn's disease is an incurable and frequently progressive entity with major impact on affected patients. Up to half of patients require surgery in the first 10 years after diagnosis and over 75% of operated patients require at least one further surgery within lifetime. In order to minimize surgical risk, modifiable risk factors such as nutritional status need to be optimized. This systematic review on preoperative nutritional support in adult Crohn's patients between 1997 and 2017 aimed to provide an overview on target populations, screening modalities, routes of administration, and expected benefits. Pertinent study characteristics (prospective vs. retrospective, sample size, control group, limitations) were defined a priori. Twenty-nine studies were retained, of which 14 original studies (9 retrospective, 4 prospective, and 1 randomized controlled trial) and 15 reviews. Study heterogeneity was high regarding nutritional regimens and outcome, and meta-analysis could not be performed. Most studies were conducted without matched control group and thus provide modest level of evidence. Consistently, malnutrition was found to be a major risk factor for postoperative complications, and both enteral and parenteral routes were efficient in decreasing postoperative morbidity. Current guidelines for nutrition in general surgery apply also to Crohn's patients. The route of administration should be chosen according to disease presentation and patients' condition. Further studies are needed to strengthen the evidence

Extremal non-BPS black holes and entropy extremization

At the horizon, a static extremal black hole solution in N=2 supergravity in four dimensions is determined by a set of so-called attractor equations which, in the absence of higher-curvature interactions, can be derived as extremization conditions for the black hole potential or, equivalently, for the entropy function. We contrast both methods by explicitly solving the attractor equations for a one-modulus prepotential associated with the conifold. We find that near the conifold point, the non-supersymmetric solution has a substantially different behavior than the supersymmetric solution. We analyze the stability of the solutions and the extrema of the resulting entropy as a function of the modulus. For the non-BPS solution the region of attractivity and the maximum of the entropy do not coincide with the conifold point.Comment: 19 pages, 4 figures, AMS-LaTeX, reference adde

Correlation of postoperative fluid balance and weight and their impact on outcomes.

Normovolemia after major surgery is critical to avoid complications. The aim of the present study was to analyze correlation between fluid balance, weight gain, and postoperative outcomes. All consecutive patients undergoing elective or emergency major abdominal surgery needing intermediate care unit (IMC) admission from September 2017 to January 2018 were included. Postoperative fluid balances and daily weight changes were calculated for postoperative days (PODs) 0-3. Risk factors for postoperative complications (30-day Clavien) and prolonged length of IMC and hospital stay were identified through uni- and multinominal logistic regression. One hundred eleven patients were included, of which 55% stayed in IMC beyond POD 1. Overall, 67% experienced any complication, while 30% presented a major complication (Clavien ≥ III). For the entire cohort, median cumulative fluid balance at the end of PODs 0-1-2-3 was 1850 (IQR 1020-2540) mL, 2890 (IQR 1610-4000) mL, 3890 (IQR 2570-5380) mL, and 4000 (IQR 1890-5760) mL respectively, and median weight gain was 2.2 (IQR 0.3-4.3) kg, 3 (1.5-4.7) kg, and 3.9 (2.5-5.4) kg, respectively. Fluid balance and weight course showed no significant correlation (r = 0.214, p = 0.19). Extent of surgery, analyzed through Δ albumin and duration of surgery, significantly correlated with POD 2 fluid balances (p = 0.04, p = 0.006, respectively), as did POD 3 weight gain (p = 0.042). Prolonged IMC stay of ≥ 3 days was related to weight gain ≥ 3 kg at POD 2 (OR 2.8, 95% CI 1.01-8.9, p = 0.049). Fluid balance and weight course showed only modest correlation. POD 2 weight may represent an easy and pragmatic tool to optimize fluid management and help to prevent fluid-related postoperative complications

Pressurized IntraPeritoneal Aerosol Chemotherapy - Practical aspects.

Pressurized Intraperitoneal Aerosol Chemotherapy (PIPAC) has been introduced as novel treatment for peritoneal carcinomatosis. Only proper patient selection, stringent safety protocol and careful surgery allow for a secure procedure. We hereby report the essentials for safe implementation. All consecutive procedures within 20 months after PIPAC implementation were analyzed with regards to practical and surgical aspects. Special emphasis was laid on modifications of technique and safety measures during the implementation process with systematic use of a dedicated checklist. Further, surgical difficulty was documented by use of a visual analogue scale (VAS). 127 PIPAC procedures were performed in 58 patients from January 2015 until October 2016. 81% of patients had at least one previous laparotomy. Median operation time was 91 min (87-103) for the first 20 cases, 93 min (IQR 88-107) for PIPAC21-50, and 103 min (IQR 91-121) for the following 77 procedures. Primary and secondary non-access occurred in 3 patients (2%), all of them having prior hyperthermic intraperitoneal chemotherapy (HIPEC). Using open Hasson technique, one single bowel lesion occurred, which was the only intraoperative complication. One 5 mm and another 10/12 mm trocar were used in 88% of procedures while additional trocars were needed in 12%. No leak of cytostatics was observed and no procedure needed to be stopped. VAS for overall difficulty of the procedure was 3 ± 2.4, and 3 ± 2.9 and 3 ± 2.5, respectively, for abdominal access and intraoperative staging. With standardized surgical approach and dedicated safety checklist, PIPAC can be safely introduced in clinical routine with minimal learning curve

Comparison of multispectral remote-sensing techniques for monitoring subsurface drain conditions

The following multispectral remote-sensing techniques were compared to determine the most suitable method for routinely monitoring agricultural subsurface drain conditions: airborne scanning, covering the visible through thermal-infrared (IR) portions of the spectrum; color-IR photography; and natural-color photography. Color-IR photography was determined to be the best approach, from the standpoint of both cost and information content. Aerial monitoring of drain conditions for early warning of tile malfunction appears practical. With careful selection of season and rain-induced soil-moisture conditions, extensive regional surveys are possible. Certain locations, such as the Imperial Valley, Calif., are precluded from regional monitoring because of year-round crop rotations and soil stratification conditions. Here, farms with similar crops could time local coverage for bare-field and saturated-soil conditions