Flow-Control Effectiveness of Convergent Surface Indentations on an Aerofoil at Low Reynolds Numbers

Passive flow control on aerofoils has largely been achieved through the use of protrusions such as vane-type vortex generators. Consequently, innovative flow-control concepts should be explored in an effort to improve current component performance. Therefore, experimental research has been performed at The University of Manchester to evaluate the flow-control effectiveness of a novel type of vortex generator made in the form of a surface indentation. The surface indentation has a trapezoidal planform. A spanwise array of indentations has been applied in a convergent orientation around the maximum-thickness location of the upper surface of a NACA-0015 aerofoil. The aerofoil has been tested in a twodimensional set-up in a low-speed wind tunnel at an angle of attack (AoA) of 3° and a chordbased blockage-corrected Reynolds number (Recorr) of ~2.70 x 105 . The baseline model has been found to suffer from a long laminar separation bubble (LSB) at low AoA. The application of the indentations at low AoA has considerably shortened the separation bubble. The indentations achieve this by shedding up-flow pairs of streamwise vortices. Despite the considerable reduction in bubble length, the increase in leading-edge suction due to the shorter bubble is limited by the removal of surface curvature and blockage (increase in surface pressure) caused locally by the convergent indentations. Furthermore, the up-flow region of the vortices, which locally weakens the pressure recovery around the trailing edge of the aerofoil by thickening the boundary layer, also contributes to this limitation. Due to the conflicting effects of the indentations, the changes in the pressure-lift and pressure-drag coefficients, i.e., cl,p and cd,p, respectively, are small. Nevertheless, the indentations have improved cl,p and cd,p beyond the uncertainty range, i.e., by ~1.3% and ~0.3%, respectively, at 3° AoA. The wake measurements show that turbulence intensity and Reynolds stresses have considerably increased in the indented case, thus implying that the indentations increase the viscous drag on the model. In summary, the convergent indentations are able to reduce the size of the LSB, but conversely, they are not highly effective in enhancing cl,p and cd,p at the tested Re

Observations on North Dakota Sponges (Haplosclerina: Spongillidae) and Sisyrids (Neuroptera: Sisyridae)

Factors influencing occurrence, distribution, and ecology of sponges and sisyrids are discussed, with emphasis on northeastern North Dakota. New state records for North Dakota sponges, Eunapius Jraguis Leidy and Ephydatia fluviatilis L. and the sisyrids, Sisyra vicaria (Hagen) and Climacia areolaris (Hagen), and new county records for C. areolaris in northwestern Minnesota and Eunapius fragilis in northeastern North Dakota are reported. A rare association of the parasite, S. vicaria with the host, Ephydatia fluviatilis is also reported. Some physicochcmical relations of Eunapius fragilis found in the Forest River, North Dakota, are discussed

Contractual Modification of Past Due and Future Child Support Payments

This comment will address the custodial parent\u27s right to contract with the supporting parent to modify court-ordered child support payments. Part II discusses how the courts have classifled contracts made to settle past due child support payments. It will also explain the defenses that some courts recognize and utilize to protect the supporting parent when the courts refuse to enforce the contracts. Part III discusses the different rationales for either enforcing or invalidating contracts that modify future child support payments. Part IV recommends that the courts allow parents to contractually modify payments and that the courts use traditional contract principles, combined with a best interests of the child test, to determine the validity of each contract

The Effects of Thermal Opportunity and Habitat on Physiological Performance in Ecologically Distinct Populations of the Florida Scrub Lizard Sceloporus woodi

An ectotherm’s ability to thermoregulate affects many physiological traits. Therefore, thermal factors are paramount when considering behavior, activity time, body temperatures, energy budget, and performance capabilities. The Florida scrub lizard (Sceloporus woodi) is a ground-dwelling lizard that occupies longleaf pine and sand pine scrub habitats in the Ocala National Forest. Here, this species’ habitat is maintained by either clear-cut logging in scrub stands, or prescribed burning in long leaf pine stands. These habitat types differ in their dominant vegetation, canopy cover, and availability of vertical perches and thus are ecologically different. I used biophysical models to measure the available environmental temperatures in longleaf pine and sand pine scrub populations. Thermal opportunity is used to describe the availability of preferred temperatures within specific habitats so as to understand the thermal constraints that may influence available activity times as well as the energy and resources spent on thermoregulation in a given environment. Longleaf pine populations had higher thermal opportunity which allowed populations to thermoregulate more effectively overall. However, when thermal quality of habitat was poor, all populations increased thermoregulatory effort despite the higher costs of thermoregulating. Furthermore, the difference in available temperature distribution in each environment was examined in the context of the thermal sensitivity of locomotor performance. Thermal performance curves were generated to compare traits associated with physiological performance. Higher operative temperatures in sand pine scrub habitats were correlated with higher critical thermal limits and thermal optima in these populations. Despite the range of preferred temperatures being the same, the data suggest that the thermal physiology of this species is evolutionarily labile. Thus, variation in thermal opportunity between longleaf pine and sand pine scrub stands is likely driving the observed divergence in thermal physiology among these populations

Contractual Modification of Past Due and Future Child Support Payments

This comment will address the custodial parent\u27s right to contract with the supporting parent to modify court-ordered child support payments. Part II discusses how the courts have classifled contracts made to settle past due child support payments. It will also explain the defenses that some courts recognize and utilize to protect the supporting parent when the courts refuse to enforce the contracts. Part III discusses the different rationales for either enforcing or invalidating contracts that modify future child support payments. Part IV recommends that the courts allow parents to contractually modify payments and that the courts use traditional contract principles, combined with a best interests of the child test, to determine the validity of each contract

Chaser: A Modern Film Noir

Chaser is a story about Devin, a city detective who has been investigating the kidnapping of the police captain???s wife, Melissa Florek. Devin???s search takes him to a seedy bar that is suspected to be a front for other illicit activities by the city???s biggest crime lord, Vincent. Although Devin???s job requires him to be a symbol of justice and good his struggles with his own demons are revealed through the subtext of his dialogue and his actions. Chaser is an homage to the independent style of neo-noir. Noir???s dramatic style of shadows, moral ambiguity, and cynicism is often seen as its own genre, when truly it is a style that can be applied to various other genres. This project paper will explore the various stylistic techniques of neo-noir as well as other movie making aesthetics. More specifically, it will elaborate on the significance of their presence within this short film and how they will make it similar to that of a modern noi

Implant Prophylaxis: The Next Best Practice Toward Asepsis in Spine Surgery.

Study designA literature review.ObjectivesAn evaluation of the contaminants prevalent on implants used for surgery and the aseptic methods being employed against them.MethodsPubMed was searched for articles published between 2000 and 2017 for studies evaluating the contaminants present on spine implants, and associated pre- and intraoperative implant processing and handling methodology suggested to avoid them. Systematic reviews, observational studies, bench-top studies, and expert opinions were included.ResultsEleven studies were identified whose major focus was the asepsis of implants to reduce the incidence of surgical site infection incidences during surgery. These studies measured the colony forming units of bacteria on sterilized implants and/or gloves from the surgeon, scrub nurse, and assistants, as well as reductions of surgical site infection rates in spine surgery due to changes in implant handling techniques. Additionally, the search included assessments of endotoxins and carbohydrates present on reprocessed implants. The suggested changes to surgical practice based on these studies included handling implants with only fresh gloves, keeping implants covered until the immediate time of use, reducing operating room traffic, avoiding reprocessing of implants (ie, providing terminally sterilized implants), and avoiding touching the implants altogether.ConclusionsBoth reprocessing (preoperative) and handling (intraoperative) of implants seem to lead to contamination of sterilized implants. Using a terminally sterilized device may mitigate reprocessing (preoperative implant prophylaxis), whereas the use of fresh gloves for handling each implant and/or a permanent shielding technique (intraoperative implant prophylaxis) could potentially avoid recontamination at the theatre

Possible Association between Expression of Chemokine Receptor-2 (CCR2) and Amyotrophic Lateral Sclerosis (ALS) Patients of North India

BACKGROUND AND OBJECTIVES: We earlier reported elevated chemokine ligand-2 (CCL2) in Indian amyotrophic lateral sclerosis (ALS) patients. We now analysed chemokine receptor-2 (CCR2), the receptor of CCL2, in these ALS patients. METHODS: Indian sporadic ALS patients (n=50) were included on the basis of El Escorial criteria. Percentage (%) of CCR2 expressing peripheral blood mononuclear cells (PBMCs) was evaluated using Flow Cytometry. Real Time Polymerase Chain Reaction (PCR) was used to quantitate CCR2 mRNA expression in PBMCs. Normal controls (n = 40) were also included for comparison. RESULTS: Flow Cytometry revealed significantly reduced CCR2 expressing PBMCs in the ALS patients. We also found a significant decline in number of CCR2 expressing PBMCs in limb onset ALS when compared to bulbar onset ALS. PBMCs from ALS patients showed substantial down-regulation of CCR2 mRNA. CCR2 mRNA expression was found to be decreased among limb ALS patients as compared to bulbar onset ALS. Further, the count of CCR2+ PBMCs and CCR2 mRNA transcript in PBMCs was significantly lower in severe and moderate ALS as compared to ALS patients with mild impairments. CONCLUSIONS: Downregulation of PBMCs CCR2 may indicate its etio-pathological relevance in ALS pathogenesis. Reduced PBMCs CCR2 may result in decreased infiltration of leukocytes at the site of degeneration as a compensatory response to ALS. CCR2 levels measurements in hematopoietic stem cells and estimation of comparative PBMCs count among ALS, disease controls and normal controls can unveil its direct neuroprotective role. However, the conclusions are restricted by the absence of neurological/non-neurological disease controls in the study