Diagnostic value of pneumoperitoneum on plain abdominal film in patients with suspected visceral perforation at Bugando Medical Centre, Mwanza, Tanzania

Background:  The presence of pneumoperitoneum on plain abdominal film has been widely used in many centres in Tanzania as primary diagnostic imaging in patients with suspected visceral perforation. However, its diagnostic value has not yet been assessed in any hospital in the country including Bugando Medical Centre (BMC), and therefore its use as a diagnostic tool in these patients is not justified. This existing knowledge gap prompted the author to conduct this study. The study aimed to determine the diagnostic value of pneumoperitoneum on plain abdominal film in patients with suspected visceral perforation in our local setting. Methods: This was a prospective cross-sectional study among patients with suspected visceral perforation at BMC from June 2017 to May 2018. Pneumoperitoneum on plain abdominal radiography was evaluated, and the findings were cross-tabulated against operative findings, the gold standard. Then, the sensitivity, specificity, accuracy, Positive Predictive Value, Negative Predictive Value and accuracy were calculated to determine the diagnostic value of pneumoperitoneum on plain abdominal film. The Kappa statistic (қ) was calculated to determine the degree of agreement with operative findings. Results: A total of 132 patients were studied. The median age of patients was 35 years. The diagnostic accuracy of pneumoperitoneum on plain abdominal film in the detection of perforation was 90.9% with sensitivity, specificity, PPV and NPV of 90.1%, 92.7%, 96.5% and 80.9% respectively. There was good agreement with operative findings (κ = 0.86). The perforations of the ileum, gastric, duodenum, colon and appendix accounted for 36.3%, 22.0%, 19.8%, 11.0% and 11.0% of cases, respectively. The sensitivity, specificity, PPV, NPV and accuracy perforations of the ileum, gastric, duodenum, colon and appendix were 61.5-100%, 31.7-46.5%, 10.6-37.7%, 85.1-100% and 38.6-59.1% respectively.  The kappa statistics showed good agreement with the operative findings (ķ = 0.76-0.89). Conclusion: The presence of pneumoperitoneum on plain abdominal film provides high diagnostic value in the detection of visceral perforation and can be employed at BMC to improve the diagnostic value in patients with suspected visceral perforation and subsequently reduce negative laparotomy and complication rates

Hypocretin/Orexin Peptides Alter Spike Encoding by Serotonergic Dorsal Raphe Neurons through Two Distinct Mechanisms That Increase the Late Afterhyperpolarization

Orexins (hypocretins) are neuropeptides that regulate multiple homeostatic processes, including reward and arousal, in part by exciting serotonergic dorsal raphe neurons, the major source of forebrain serotonin. Here, using mouse brain slices, we found that, instead of simply depolarizing these neurons, orexin-A altered the spike encoding process by increasing the postspike afterhyperpolarization (AHP) via two distinct mechanisms. This orexin-enhanced AHP (oeAHP) was mediated by both OX1 and OX2 receptors, required Ca(2+) influx, reversed near EK, and decayed with two components, the faster of which resulted from enhanced SK channel activation, whereas the slower component decayed like a slow AHP (sAHP), but was not blocked by UCL2077, an antagonist of sAHPs in some neurons. Intracellular phospholipase C inhibition (U73122) blocked the entire oeAHP, but neither component was sensitive to PKC inhibition or altered PKA signaling, unlike classical sAHPs. The enhanced SK current did not depend on IP3-mediated Ca(2+) release but resulted from A-current inhibition and the resultant spike broadening, which increased Ca(2+) influx and Ca(2+)-induced-Ca(2+) release, whereas the slower component was insensitive to these factors. Functionally, the oeAHP slowed and stabilized orexin-induced firing compared with firing produced by a virtual orexin conductance lacking the oeAHP. The oeAHP also reduced steady-state firing rate and firing fidelity in response to stimulation, without affecting the initial rate or fidelity. Collectively, these findings reveal a new orexin action in serotonergic raphe neurons and suggest that, when orexin is released during arousal and reward, it enhances the spike encoding of phasic over tonic inputs, such as those related to sensory, motor, and reward events. SIGNIFICANCE STATEMENT: Orexin peptides are known to excite neurons via slow postsynaptic depolarizations. Here we elucidate a significant new orexin action that increases and prolongs the postspike afterhyperpolarization (AHP) in 5-HT dorsal raphe neurons and other arousal-system neurons. Our mechanistic studies establish involvement of two distinct Ca(2+)-dependent AHP currents dependent on phospholipase C signaling but independent of IP3 or PKC. Our functional studies establish that this action preserves responsiveness to phasic inputs while attenuating responsiveness to tonic inputs. Thus, our findings bring new insight into the actions of an important neuropeptide and indicate that, in addition to producing excitation, orexins can tune postsynaptic excitability to better encode the phasic sensory, motor, and reward signals expected during aroused states

A Data-Driven Analysis of a Tactical Surface Scheduler

NASA's Airspace Technology Demonstration-2 (ATD-2) integrates arrival, departure, and surface operations to extend integrated traffic sequencing all the way from the gate to the overhead stream and back again for multi-airport, metroplex environments. A key concept of ATD-2 centers on surface scheduling that allows aircraft to taxi, climb, and insert within the overhead stream with minimal interruptions. A core principle is to allow aircraft to absorb delay at the gate prior to engine start in order to reduce overall fuel burn and emissions. To achieve these goals, it is necessary for the scheduler to properly balance the demand at the runway with the available capacity while also predicting accurate takeoff times. This paper provides a data-driven analysis of the runway demand capacity balancing and measures the accuracy of schedules that are generated while running in a live operational environment at the Charlotte Douglas International Airport. We found that using minimum-time wake vortex separation constraints to define runway capacity resulted in scheduling departure operations at a slightly higher rate than the runway was operating and we discovered a surprising relationship between the runway rate and the accuracy of the schedules

Effects of Carbohydrate-Based and Protein-Carbohydrate Rations on Wild Bobwhite Nesting and Harvest Demographics

Northern bobwhite (Colinus virginianus) reproduction is a nutrient-intensive process. Arthropods are essential for breeding bobwhite hens and their offspring. Traditional supplemental feeding programs use corn and milo and typically neglect the protein needs of bobwhites. Commercial bobwhite rations are widely available but are seldom used in feeding programs due to high cost and lack of an appropriate supplement for field use. We compared the effect of a protein-carbohydrate ration (PC) to the effects of a carbohydrate only ration (CO) on: (1) bobwhite hen nesting demographics (clutch size, ordinal clutch initiation date, Mayfield nest survival), and (2) fall relative abundance (coveys moved/hr hunting). Nesting parameters for bobwhites based on a sample of 60 hens during the 2008 breeding season in South Texas were statistically similar based on overlap of 95% confidence intervals for both the PC and CO supplements. Mayfield nest success was high for both the PC ration (75.2%) and the CO ration (73.1%). Coveys moved during hunting (4.17 6 14 coveys/hr in pastures with CO feed and 4.2 6 12.5 coveys/hr in pastures with PC feed) did not differ during the 2008–2009 hunting season. The 2009 nesting season was a failure because all study animals died due to drought. Weekly Kaplan-Meier survival estimates of bobwhite hens were 6 times higher in 2008 than in 2009. The PC ration in our study provided no benefit to bobwhite populations or enhancement of wild bobwhite reproductive parameters over the CO ration. The additional cost of using PC over CO is not justified based on our results

VNTR DNA Variation in Siberian Indigenous Populations

This is the published version. Copyright 1995 Wayne State University Press.The VNTR loci D7S104, D11S129, D18S17, D20S15, and D21S112 in three indigenous Siberian populations were analyzed to determine the populations' genetic structure. Using the Kolmogorov- Smirnov test, we found that the Siberian indigenous populations of Surinda and Sulamai are separated at the D1 IS 129 locus (p < 0.05). However, the population of Poligus is genetically homogeneous compared with the villages of Sulamai and Surinda. Principal component plots for the sets of VNTR loci cluster the Siberian groups together, reflecting the homogeneity of these populations. An analysis of mean per locus heterozygosity versus the distance from the centroid of distribution suggests gene flow into Sulamai but little genetic exchange with Surinda and Poligus. Ultimately, the VNTR data reflect the genetic distinctiveness of the Kets and the Evenki

3. Launching the New Enterprise

As the academic year of 1945-46 approached, the intensity of activity in preparation for actually opening the school in the fall term became overwhelming. Incredible though it may seem, Ives and Day were able in a period of a few weeks to assemble the nucleus of a faculty, several of whom formed a continuing source of counsel and advice both during the school’s formative years and thereafter. Includes: The First Dean and the School’s Dedication; A Participant’s View of the Early Years; Ives Moves On; Several Views of Martin P. Catherwood; The Founders

Cognitive Information Processing

Contains reports on four research projects.National Science Foundation (Grant SED76-81985)Associated Press (Grant)Providence Gravure, Inc. (Grant)Taylor Publishing Company (Grant