The Application of Recent Techniques in Flight Flutter Testing

The relative merits of sinusoidal excitation versus random atmospheric turbulence was investigated. The randomdec and autocorrelation methods were used to analyze data from a Learjet flight test. A parameter identification digital program, using least squares approach, was developed to determine the aeroelastic characteristics of a two mode system. The flight test program, computer program, and data reduction procedure is presented. Final results of the two modes of excitation obtained by Randomdec method are discussed

Implantation of 3D-Printed Patient-Specific Aneurysm Models into Cadaveric Specimens: A New Training Paradigm to Allow for Improvements in Cerebrovascular Surgery and Research.

AimTo evaluate the feasibility of implanting 3D-printed brain aneurysm model in human cadavers and to assess their utility in neurosurgical research, complex case management/planning, and operative training.MethodsTwo 3D-printed aneurysm models, basilar apex and middle cerebral artery, were generated and implanted in four cadaveric specimens. The aneurysms were implanted at the same anatomical region as the modeled patient. Pterional and orbitozygomatic approaches were done on each specimen. The aneurysm implant, manipulation capabilities, and surgical clipping were evaluated.ResultsThe 3D aneurysm models were successfully implanted to the cadaveric specimens' arterial circulation in all cases. The features of the neck in terms of flexibility and its relationship with other arterial branches allowed for the practice of surgical maneuvering characteristic to aneurysm clipping. Furthermore, the relationship of the aneurysm dome with the surrounding structures allowed for better understanding of the aneurysmal local mass effect. Noticeably, all of these observations were done in a realistic environment provided by our customized embalming model for neurosurgical simulation.Conclusion3D aneurysms models implanted in cadaveric specimens may represent an untapped training method for replicating clip technique; for practicing certain approaches to aneurysms specific to a particular patient; and for improving neurosurgical research

High-Flow Vascular Malformations in Children.

Children can have a variety of intracranial vascular anomalies ranging from small and incidental with no clinical consequences to complex lesions that can cause substantial neurologic deficits, heart failure, or profoundly affect development. In contrast to high-flow lesions with direct arterial-to-venous shunts, low-flow lesions such as cavernous malformations are associated with a lower likelihood of substantial hemorrhage, and a more benign course. Management of vascular anomalies in children has to incorporate an understanding of how treatment strategies may affect the normal development of the central nervous system. In this review, we discuss the etiologies, epidemiology, natural history, and genetic risk factors of three high-flow vascular malformations seen in children: brain arteriovenous malformations, intracranial dural arteriovenous fistulas, and vein of Galen malformations

dNBR imagery and xeric pine-oak forest stand characteristics for fires of different severity in Great Smoky Mountains National Park

Fire suppression has changed forest structure and composition on xeric sites in the southern Appalachians from open, pine-oak dominated stands to closed canopy, mixed hardwood stands. Improved understanding of fire-related tools and ecological responses will improve effectiveness of fire management aimed at restoring pre-fire suppression forest communities on these xeric sites. Although occurrence of fire is known to be related to ecosystem functioning, vegetation responses to multi-severity fires are not as well understood in the southern Appalachians. Additionally, the relationship between satellite imagery and ground-based methods for designating burn severity (post-fire term describing fire severity) are not established for the Great Smoky Mountains National Park (GSMNP). The purpose of my study was to (1) determine if burn severity designations were consistent between satellite imagery and ground-based methods, and (2) evaluate vegetation responses to different burn severities on xeric sites dominated by pine (Pinus) and oak (Quercus) species in the GSMNP. Plots were randomly located using satellite-based (dNBR) burn severity maps. For part (1) of my study these sites were ground-truthed using the FIREMON Composite Burn Index (CBI). Initial scatter plots between CBI and dNBR indicated a saturated growth relationship and square-root transformed dNBR data were overall strongly correlated to ground-based ratings (CBI) for 169 total plots (p<0.001, R2=0.90). Strong relationships were found between CBI and dNBR across different xeric forest types and time since burn categories. For part (2) of my study, variables related to stand regeneration were measured at the ground, mid-story, and overstory layers across different burn severities for 48 plots. Differences in post-fire forest structure and composition across burn severity classifications were tested using analyses of variance and relationships between stand variables were evaluated using linear regression. Results showed overstory mortality was significantly higher in moderate and high severity sites versus low severity and no burn sites. Stand density and basal area were lowest in high severity sites and litter layer depth decreased significantly in higher severity fires. Pine regeneration did not vary across burn severities and oak regeneration was highest in moderate severity sites. Mixed mesophytic regeneration was highest in sites absent of fire. Desired pine and oak regeneration was greatest in moderate burn severity sites. Changes in species composition following fire may have been caused by greater amount of exposed mineral soil, increased light penetration to forest floor, and reduced mid-story stem densities. Overall results from both studies show that (1) burn severity can be predicted from satellite imagery and (2) different burn severities are associated with different forest structure and composition related to pine and oak regeneration on xeric sites in GSMNP

A comparative study of ketofol and fentafol for evacuation of retained products of conception (ERPC)

Background: Intravenous balanced anesthesia (IVA) is desirable during the evacuation of retained products of conception (ERPC) to avoid the use of inhalational anesthetics agents that may cause uterus relaxation, the possibility of bleeding, and the risk of uterus perforation.Objectives: The aim of this study was to compare the efficacy and safety of ketofol (a mixture of propofol and ketamine) versus fentafol (a mixture of propofol and fentanyl) during the ERPC.Methods: A double-blind, randomized comparative study was conducted among a total of 60 women of childbearing age categorized as grades I and II according to the American Society of Anesthesiologist (ASA), presented for ERPC. The patients were selected and randomized blindly into two groups (K group and F group), with 30 patients in each group. The K group was given ketofol (1ml containing 5mg of propofol and 5mg of ketamine) and F group was given fentafol (1ml containing 5mg propofol and 5mcg fentanyl). An intravenous loading dose of ketofol or fentafol was given slowly, with doses ranging from 1ml to 2ml/10kg, to reach level 5 or 6 of the Ramsay Scale of Sedation (RSS), followed by small incremental doses which were given when RSS dropped to 4. Hemodynamic parameters, success, and side effects were assessed throughout the procedures.Results: K group demonstrated a significant increase in heart rate (HR) and blood pressure (BP), compared to significant decreases in the F group. Decreases in oxygen saturation (SpO2) and respiratory rate (RR) were observed more in the F group. However, no patients developed hypertension, hypotension, apnea, hypoxemia or serious adverse effects. Ketofol showed less propofol consumption and a short recovery time.Conclusions: Both ketofol and fentafol offer optimum conditions for ERPC. Ketofol is characterized by more stable hemodynamic parameters, a smaller dosage and faster recovery. [Ethiop.J. Health Dev. 2019; 33(2):88-93]Key words: Propofol, ketamine, fentanyl, retained products of conception (RPC), ketofol, fentafo

ECONOMIC FEASIBILITY STUDY FOR MUSHROOM PRODUCTION IN SMALL ENTERPRISES

Many countries are interested in production of Mushroom because of its high nutritive value. In Egypt, production of Mushroom is about 0.06% of the world production. Therefore, the present study aimed to investigate the economic feasibility of Mushroom production to evaluate the predicted profits in Egypt. The results showed that production of Mushroom significantly increased by 0.15 thousand ton/year. China, U.S.A and Germany are the top producing countries where 46.11% from the total world production is produced by these countries. The top exporting countries are China, Poland and Ireland since they export 57.67% from the total world exports of Mushroom. Meanwhile, Germany, Japan, England and U.S.A. are the top importing countries which import about 574.82% thousand tons/year through (2002- 2004). The study revealed that production of Mushroom is profitable as an enterprise for small investors in Egypt. Total production costs per year is about L.E. 8000. This small project gives two work opportunities and income of L.E. 12 thousand per year. The Internal rate of return of the enterprise is about 35% and the Payback period is about three years. Mushroom, the simple rate of return on investment is about 36%. The sensitivity analysis indicated that the least Internal rate of return supposing reduction of total income, is about 10% or increasing the total costs by 10%, the least Internal rate of return reached to14%. Whereas, simple rate of return on investment was estimated by 24% which was more than the interest rate in commercial banks that reached 10%. Therefore, This study recommends encouraging young-people enterprises in rural communities in new lands to produce Mushroom, by introducing technical consults, financial facilities for small investors. Also, limiting production and marketing difficulties, improving efficiency of marketing systems. In addition to maximizing production of Mushroom for exporting to the international markets and organizing training courses for spotting light on the economic feasibility of Mushroom to increase number of the investors to produce Mushroom

Implantation of 3D-Printed Patient-Specific Aneurysm Models into Cadaveric Specimens: A New Training Paradigm to Allow for Improvements in Cerebrovascular Surgery and Research

Aim. To evaluate the feasibility of implanting 3D-printed brain aneurysm model in human cadavers and to assess their utility in neurosurgical research, complex case management/planning, and operative training. Methods. Two 3D-printed aneurysm models, basilar apex and middle cerebral artery, were generated and implanted in four cadaveric specimens. The aneurysms were implanted at the same anatomical region as the modeled patient. Pterional and orbitozygomatic approaches were done on each specimen. The aneurysm implant, manipulation capabilities, and surgical clipping were evaluated. Results. The 3D aneurysm models were successfully implanted to the cadaveric specimens’ arterial circulation in all cases. The features of the neck in terms of flexibility and its relationship with other arterial branches allowed for the practice of surgical maneuvering characteristic to aneurysm clipping. Furthermore, the relationship of the aneurysm dome with the surrounding structures allowed for better understanding of the aneurysmal local mass effect. Noticeably, all of these observations were done in a realistic environment provided by our customized embalming model for neurosurgical simulation. Conclusion. 3D aneurysms models implanted in cadaveric specimens may represent an untapped training method for replicating clip technique; for practicing certain approaches to aneurysms specific to a particular patient; and for improving neurosurgical research

Bringing high-grade arteriovenous malformations under control: clinical outcomes following multimodality treatment in children.

OBJECTIVE:Brain arteriovenous malformations (AVMs) consist of dysplastic blood vessels with direct arteriovenous shunts that can hemorrhage spontaneously. In children, a higher lifetime hemorrhage risk must be balanced with treatment-related morbidity. The authors describe a collaborative, multimodal strategy resulting in effective and safe treatment of pediatric AVMs. METHODS:A retrospective analysis of a prospectively maintained database was performed in children with treated and nontreated pediatric AVMs at the University of California, San Francisco, from 1998 to 2017. Inclusion criteria were age ≤ 18 years at time of diagnosis and an AVM confirmed by a catheter angiogram. RESULTS:The authors evaluated 189 pediatric patients with AVMs over the study period, including 119 ruptured (63%) and 70 unruptured (37%) AVMs. The mean age at diagnosis was 11.6 ± 4.3 years. With respect to Spetzler-Martin (SM) grade, there were 38 (20.1%) grade I, 40 (21.2%) grade II, 62 (32.8%) grade III, 40 (21.2%) grade IV, and 9 (4.8%) grade V lesions. Six patients were managed conservatively, and 183 patients underwent treatment, including 120 resections, 82 stereotactic radiosurgery (SRS), and 37 endovascular embolizations. Forty-four of 49 (89.8%) high-grade AVMs (SM grade IV or V) were treated. Multiple treatment modalities were used in 29.5% of low-grade and 27.3% of high-grade AVMs. Complete angiographic obliteration was obtained in 73.4% of low-grade lesions (SM grade I-III) and in 45.2% of high-grade lesions. A periprocedural stroke occurred in a single patient (0.5%), and there was 1 treatment-related death. The mean clinical follow-up for the cohort was 4.1 ± 4.6 years, and 96.6% and 84.3% of patients neurologically improved or remained unchanged in the ruptured and unruptured AVM groups following treatment, respectively. There were 16 bleeding events following initiation of AVM treatment (annual rate: 0.02 events per person-year). CONCLUSIONS:Coordinated multidisciplinary evaluation and individualized planning can result in safe and effective treatment of children with AVMs. In particular, it is possible to treat the majority of high-grade AVMs with an acceptable safety profile. Judicious use of multimodality therapy should be limited to appropriately selected patients after thorough team-based discussions to avoid additive morbidity. Future multicenter studies are required to better design predictive models to aid with patient selection for multimodal pediatric care, especially with high-grade AVMs

HIRA directly targets the enhancers of selected cardiac transcription factors during in vitro differentiation of mouse embryonic stem cells

HIRA is a histone chaperone known to modulate gene expression through the deposition of H3.3. Conditional knockout of Hira in embryonic mouse hearts leads to cardiac septal defects. Loss of function mutation in HIRA, together with other chromatin modifiers, was found in patients with congenital heart diseases. However, the effects of HIRA on gene expression at earlier stages of cardiogenic mesoderm differentiation have not yet been studied. Differentiation of mouse embryonic stem cells (mESCs) towards cardiomyocytes mimics some of these early events and is an accepted model of these early stages. We performed RNA-Seq and H3.3-HA ChIP-seq on both WT and Hira-null mESCs and early cardiomyocyte progenitors of both genotypes. Analysis of RNA-seq data showed differential down regulation of cardiovascular development-related genes in Hira-null cardiomyocytes compared to WT cardiomyocytes. We found HIRA-dependent H3.3 deposition at these genes. In particular, we observed that HIRA influenced directly the expression of the transcription factors Gata6, Meis1 and Tbx2, essential for cardiac septation, through H3.3 deposition. We therefore identified new direct targets of HIRA during cardiac differentiation

A clinical evaluation committee assessment of recombinant human tissue factor pathway inhibitor (tifacogin) in patients with severe community-acquired pneumonia

INTRODUCTION: The purpose of this analysis was to determine the potential efficacy of recombinant human tissue factor pathway inhibitor (tifacogin) in a subpopulation of patients with community-acquired pneumonia (CAP) from a phase III study of severe sepsis. METHODS : A retrospective review of patients with suspected pneumonia was conducted by an independent clinical evaluation committee (CEC) blinded to treatment assignment. The CEC reanalyzed data from patients enrolled in an international multicenter clinical trial of sepsis who had a diagnosis of pneumonia as the probable source of sepsis. The primary efficacy measure was all-cause 28-day mortality. RESULTS: Of 847 patients identified on case report forms with a clinical diagnosis of pneumonia, 780 (92%) were confirmed by the CEC to have pneumonia. Of confirmed pneumonia cases, 496 (63.6%) met the definition for CAP. In the CEC CAP population, the mortality rates of the tifacogin and placebo groups were 70/251 (27.9%) and 80/245 (32.7%), respectively. The strongest signals were seen in patients with CAP not receiving concomitant heparin, having microbiologically confirmed infection, or having the combination of documented infection and no heparin. The reduction in mortality in this narrowly defined subgroup when treated with tifacogin compared with placebo was statistically significant (17/58 [29.3%] with tifacogin and 28/54 [51.9%] with placebo; unadjusted P value of less than 0.02). CONCLUSIONS: Tifacogin administration did not significantly reduce mortality in any severe CAP patient. Exploratory analyses showed an improved survival in patients who did not receive concomitant heparin with microbiologically confirmed infections. These data support the rationale of an ongoing phase III study exploring the potential benefit of tifacogin in severe CAP. TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT00084071