Static and dynamic stability analysis of the space shuttle vehicle-orbiter

The longitudinal static and dynamic stability of a Space Shuttle Vehicle-Orbiter (SSV Orbiter) model is analyzed using the FLEXSTAB computer program. Nonlinear effects are accounted for by application of a correction technique in the FLEXSTAB system; the technique incorporates experimental force and pressure data into the linear aerodynamic theory. A flexible Orbiter model is treated in the static stability analysis for the flight conditions of Mach number 0.9 for rectilinear flight (1 g) and for a pull-up maneuver (2.5 g) at an altitude of 15.24 km. Static stability parameters and structural deformations of the Orbiter are calculated at trim conditions for the dynamic stability analysis, and the characteristics of damping in pitch are investigated for a Mach number range of 0.3 to 1.2. The calculated results for both the static and dynamic stabilities are compared with the available experimental data

A new assemblage of ray-finned fishes (Teleostei) from the Lower Oligocene “Schistes à Meletta” from the Glières plateau, Bornes Massif, eastern France

A recently discovered fish assemblage from the “Schistes à Meletta” facies (Lower Oligocene) of the Glières Plateau, Bornes Massif, Haute–Savoie, eastern France is described. The assemblage, comprising specimens ranging from fully-articulated skeletons to isolated scattered ossifications, is composed of Anenchelum cf. glarisianum, Pristigenys sp., Fistularia sp., Caranx cf. glarisianus alongside indeterminate teleosts. This new assemblage greatly increases the fish diversity previously known from the “Schistes à Meletta” of this area. The fauna shows biogeographic affinities with assemblages from the Peritethys domain, in particular from the Helvetic molassic basin and from the Paratethys. The genera identified at the Glières locality are represented today by species living in tropical nearshore environments together with species from the open sea. A possible explanation is that the environment of deposition was rather deep, and that shallow-water fishes were brought in by turbidity currents

New Regeneration process of heavy metals loaded chelating resin

An alternative to the classical acid-base regeneration of chelating resins loaded with heavy metals is investigated. The new process consists in recovering the heavy metals with recyclable soluble complexing agents. The semiclosed reactor includes a fixed bed and a stirred tank. A three-parameter model, which implies a double equilibrium in series, is introduced. When less than 10 % of the metal is still fixed on the resin at the end of the desorption, a simplified form of the model with two parameters, which describes a quick equilibrium followed by a first-order kinetics reaction, is proposed. Both forms of the model can simulate results for different experimental conditions (polymer and metal types, polymer initial concentration). It was observed for both cases that the first equilibrium constant depends on the polymer type and that the rate constant of desorption depends on the metal type. The scale-up of desorption is then conducted at mini-pilot scale. Scale-up criteria tend to minimize the desorption time and the soluble polymer quantity used

The systemic deletion of interleukin-1α reduces myocardial inflammation and attenuates ventricular remodeling in murine myocardial infarction.

Myocardial inflammation following myocardial infarction (MI) is crucial for proper myocardial healing, yet, dysregulated inflammation may promote adverse ventricular remodeling and heart failure. IL-1 signaling contributes to these processes, as shown by dampened inflammation by inhibition of IL-1β or the IL-1 receptor. In contrast, the potential role of IL-1α in these mechanisms has received much less attention. Previously described as a myocardial-derived alarmin, IL-1α may also act as a systemically released inflammatory cytokine. We therefore investigated the effect of IL-1α deficiency on post-MI inflammation and ventricular remodeling in a murine model of permanent coronary occlusion. In the first week post-MI, global IL-1α deficiency (IL-1α KO mice) led to decreased myocardial expression of IL-6, MCP-1, VCAM-1, hypertrophic and pro-fibrotic genes, and reduced infiltration with inflammatory monocytes. These early changes were associated with an attenuation of delayed left ventricle (LV) remodeling and systolic dysfunction after extensive MI. In contrast to systemic Il1a-KO, conditional cardiomyocyte deletion of Il1a (CmIl1a-KO) did not reduce delayed LV remodeling and systolic dysfunction. In conclusion, systemic Il1a-KO, but not Cml1a-KO, protects against adverse cardiac remodeling after MI due to permanent coronary occlusion. Hence, anti-IL-1α therapies could be useful to attenuate the detrimental consequences of post-MI myocardial inflammation

Modeling of heavy metals adsorption to a chelating resin in a fluidized bed reactor

Adsorption to a chelating resin (Chelamine Std.) is a method for recovering heavy metals from wastewater contg. very light quantities of heavy metals (<0.3 mol m-3, which approx. corresponds to 20 ppm). A thermodynamical study in a closed vessel showed that equil. is well represented by a Langmuir isotherm. Adsorption kinetics in a continuous stirred tank reactor were also conducted. Expts. were simulated by a global kinetics model comprising mass transfer in a liq. film around the resin particles, with diffusion through the pores and reaction on the adsorption sites. Kinetics has been found to be limited by film mass transfer for all metals studied (Cu2+, Ni2+, Co2+ and Zn2+). The mass transfer coeff. kL was found to be around 10-4 m s-1. Adsorption of heavy metals was then carried out at mini-pilot scale. Problems due to a decrease in particles mean radius during the adsorption prompted us to use a fluidized bed. It is also possible with this reactor to treat solns. contg. suspended solids which would clog fixed beds. The decrease in particle radius (or increase in apparent d. of the resin) produces a contraction of the fluidized bed: unloaded particles remain at the top of the bed and a d. gradient appears throughout the column, leading to a stabilization of the fluidized bed. The measured phenomenon is well described by a liq. plug flow model with immobile resin in the column. As for the adsorption in the continuous stirred tank, the Langmuir model and the kinetics limited by film mass transfer were considered. The mass transfer coeff. kL was adjusted to a value around 10-5 m s-1. [on SciFinder (R)

The first three dimensional fossils of Cretaceous sclerorhynchid sawfish Asflapristis cristadentis gen et sp nov and implications for the phylogenetic position of the Sclerorhynchoidei (Chondrichthyes)

A new fossil batoid (ray) Asflapristis cristadentis gen. et sp. nov. is described from six exceptionally well-preserved, three-dimensional skeletal remains from the Turonian (Late Cretaceous) of Morocco. Mechanical and acid preparation and CT scanning of these specimens reveal details of much of the proximal skeleton, especially the skull, synarcual and pectoral skeleton, with only the more distal parts of the skeleton missing. These fossils represent a relatively large animal (62 cm preserved length, estimated total length to approximately 2 meters) possessing a robust rostrum that lacks enlarged rostral denticles. It has a narrow and small chondrocranium with jaws that are relatively large compared to the rest of the skull and robust with highly ornamented teeth that lack cusps. The branchial skeleton shows a large second hypobranchial without anterior process which was probably fused to the basibranchial as in other sclerorhynchoids. The synarcual is large and lacks centra through its entire length, and with no direct connection to the pectoral girdle was observed. Pectoral fins probably possessed enlarged proximal elements (propterygium, mesopterygium and metapterygium), the reduced articulation facet between the coracoid with the pectoral elements was reduced. A phylogenetic analysis using both parsimony and bayesian methods was performed incorporating this new taxon. Both analyses recovered a phylogenetic topology that places the sclerorhynchoids in a close relation to rajoids and clearly separated from the morphologically similar Pristidae within the Rhinopristiformes. In respect to the extant taxa, the phylogenies generated are similar to that obtained in molecular analysis of modern batoids. The palaeoecological implication of this discovery suggests that the Asfla assemblage was not from a ‘normal’ open carbonate shelf but rather a restricted environment favouring a low diversity chondrichthyan fauna

Kinetic modeling of free radical polymerization of styrene initiated by the bifunctional initiator 2,5-dimethyl-2,5-bis(2-ethyl hexanoyl peroxy) hexane

This paper deals with the kinetic study of bulk free radical polymerization of styrene initiated with the commercial bifunctional initiator 2,5-dimethyl-2,5-bis(2-ethyl hexanoyl peroxy)hexane (Lupersol 256). The polymerization kinetics is investigated by DSC measurement for temperatures between 80 and 110°C and for initiator initial concentration from 0.115 up to 0.46 mol%. The experimental conversion and reaction rate are compared and discussed with the calculated values. For modeling the polymerization rate, a reaction scheme similar to the one given by Yoon and Choi (Polymer 1992;33(21):4582–4591) has been used and adapted. A detailed diffusional and semi-empirical model proposed by Chiu et al. (Macromolecules 1983;16(3):348–357) has been modified by Rouge (Etude de la polymérisation radicalaire du styrène initiée par un amorceur bifonctionnel dans un réacteur tubulaire à recyclage, Diploma work, DC, EPF, Lausanne, 1997) in order to describe these results. The model allows the description of the number molecular weight, but the polydispersity is underestimated for conversion higher than 70%. For temperature higher than 100°C, thermal initiation must be taken into account. The efficiency factor is found close to 1, but seems to decrease for temperatures above 100°C

Consistent limitation of growth by high temperature and low precipitation from range core to southern edge of European beech indicates widespread vulnerability to changing climate

© 2016 The Author(s)The aim of our study was to determine variation in the response of radial growth in $\textit{Fagus sylvatica}$ L (European Beech) to climate across the species full geographical distribution and climatic tolerance. We combined new and existing data to build a database of 140 tree-ring chronologies to investigate patterns in growth–climate relationships. Our novel meta-analysis approach has allowed the first investigation of the effect of climate on tree growth across the entire geographical distribution of the species. We identified key climate signals in tree-ring chronologies and then investigated how these varied geographically and according to mean local climate, and by tree age and size. We found that the most important climate variables significantly correlated with growth did not show strong geographical patterns. Growth of trees in the core and at the southern edge of the distribution was reduced by high temperature and low precipitation during the growing season, and by high temperatures in the previous summer. However, growth of trees growing in warmer and drier locations was more frequently significantly correlated with summer precipitation than other populations. Additionally, the growth of older and larger trees was more frequently significantly correlated with previous summer temperature than younger and smaller trees. Trees growing at the south of the species geographical distributions are often considered most at risk from climate change, but our results indicate that radial growth of populations in other areas of the distribution is equally likely to be significantly correlated with summer climate and may also be vulnerable. Additionally, tree-rings from older trees contain particular growth–climate relationships that are rarely found in younger trees. These results have important implications for predicting forest carbon balance, resource use and likely future changes to forest composition across the continent.University of Cambridge; Clare College, Cambridge; Natural Environment Research Council (Grant ID: NE/G002118/1

Pengaruh bentuk atraktor terhadap jumlah penempelan telur Cumi-Cumi di perairan Desa Kalasey Satu Kecamatan Mandolang Kabupaten Minahasa

Cumi-cumi merupakan salah satu inovasi pemanfaatan tanpa merusak lingkungan. Secara umum atraktor terdiri dari dua bentuk yaitu bentuk silinder dan bentuk kotak. Penelitian ini bertujuan untuk mengetahui jenis cumi-cumi yang menempel pada atraktor silinder dan atraktor persegi serta untuk Mengetahui apakah bentuk atraktor berpengaruh terhadap jumlah penempelan telur cumi-cumi. Adapun analisis data menggunakan metode Uji Beda Dua Mean Independent dengan rumus The separate model t-test.Berdasarkan hasil identifikasi morfologis diperoleh informasi bahwa jenis telur cumi-cumi yang menempel adalah famili Loliginidae, yaitu genus Sepioteuthis lessoniana. Adapun hasil analisis menggunakan rumus The seprate model t-test menunjukan bahwa = 2,77 &gt; = 2,13 hasil ini menjelaskan bahwa perlakuan bentuk atraktor menyebabkan perbedaan jumlah penempelan telur cumi-cumi, dimana atraktor bentuk silinder lebih baik dibandingkan dengan bentuk kota