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Extraterrestrial microspherules from Bajada del Diablo, Chubut, Argentina
No full textAbstractThe Quaternary infilling of a circular structure located in Bajada del Diablo, Chubut Province, Argentina has been proposed as a crater strewn field in previous studies. Here we report the finding of about 65 microspherules collected in a trench excavated in the center of the structure. The majority of hand-picked specimens are single, but some of them exhibit compound forms. The single specimens are spherical with a mean size of 137 μm, whereas the more complex samples show peduncles and drop shapes. Dendritic crystal growth is recognized in the internal structure of some broken microspherules. Preliminary chemical composition from the surface and center of microspherules was determined by energy dispersive spectrometry employing EDS. Quantitative EMPA and XRD analysis indicate that the microspherules are mainly composed of Fe and O with magnetite, Fe0 with subordinate wüstite. Following consideration of possible anthropogenic and volcanic origins, these spherulites are ascribed to an extraterrestrial input. An accumulation rate of 47 microspherules per m2/yr is estimated for the studied sediments. This value is two orders of magnitude higher than the reference flux for cosmic dust estimated for the last 1 Ma in the Transantarctic Mountains. The microspherules might have been generated as a byproduct of asteroid entry in the atmosphere
The immersed-body gas-solid interaction model for blast analysis in fractured solid media
No full textAbstractBlast-induced fractures are simulated by a novel gas-solid interaction model, which combines an immersed-body method and a cohesive zone fracture model. The approach employs a finite element fluid model and a combined finite-discrete element solid model. This model is fully coupled and simulates the whole blasting process including gas pressure impulse, shock wave propagation, gas expansion, fragmentation and burden movement phases. In the fluid model, the John-Wilkins-Lee equation of state is introduced to resolve the relationship between pressure and density of the highly compressible gas in blasts and explosions. A Q-scheme is used to stabilise the model when solving extremely high pressure situations. Two benchmark tests, blasting cylinder and projectile fire, are used to validate this coupled model. The results of these tests are in good agreement with experimental data. To demonstrate the potential of the proposed method, a blasting engineering simulation with shock waves, fracture propagation, gas-solid interaction and flying fragments is simulated
Phospholipase C-related catalytically inactive protein can regulate obesity, a state of peripheral inflammation
No full textSummaryObesity is defined as abnormal or excessive fat accumulation. Chronic inflammation in fat influences the development of obesity-related diseases. Many reports state that obesity increases the risk of morbidity in many diseases, including hypertension, dyslipidemia, type 2 diabetes, coronary heart disease, stroke, sleep apnea, and breast, prostate and colon cancers, leading to increased mortality. Obesity is also associated with chronic neuropathologic conditions such as depression and Alzheimer's disease. However, there is strong evidence that weight loss reduces these risks, by limiting blood pressure and improving levels of serum triglycerides, total cholesterol, low-density lipoprotein (LDL)-cholesterol, and high-density lipoprotein (HDL)-cholesterol. Prevention and control of obesity is complex, and requires a multifaceted approach. The elucidation of molecular mechanisms driving fat metabolism (adipogenesis and lipolysis) aims at developing clinical treatments to control obesity. We recently reported a new regulatory mechanism in fat metabolism: a protein phosphatase binding protein, phospholipase C-related catalytically inactive protein (PRIP), regulates lipolysis in white adipocytes and heat production in brown adipocytes via phosphoregulation. Deficiency of PRIP in mice led to reduced fat accumulation and increased energy expenditure, resulting in a lean phenotype. Here, we evaluate PRIP as a new therapeutic target for the control of obesity
Bio inspired synthesis of monodispersed silver nano particles using Sapindus emarginatus pericarp extract – Study of antibacterial efficacy
No full textAbstractThe synthesis of silver nanoparticles employing aqueous extract obtained from the dried pericarp of “Sapindus emarginatus” is reported. Transmission electron microscopy divulges that the silver nanoparticles are not agglomerated and are moderately mono dispersed. Size of the particle ranges from 5 to 20nm with an average particle size of 10nm. Ultraviolet–visible spectra recorded show typical surface plasmon resonance (SPR) at 400nm. X-ray diffraction analysis reveals the crystalline nature of the synthesized silver nanoparticles with face-centred cubic (FCC) geometry. Silver nanoparticles thus obtained demonstrated remarkable antibacterial activity against Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Proteus mirabilis, Proteus vulgaris, Klebsiella pneumonia, Pseudomonas aeruginosa and Vibrio cholerae. Freshly prepared samples and sample containing 6nm silver nanoparticles in particular exhibited enhanced activity against gram positive bacteria. The minimal inhibitory concentration was found to be in the range of 150–250μg/mL
Subsyndromal delirium compared with delirium, dementia, and subjects without delirium or dementia in elderly general hospital admissions and nursing home residents
No full textAbstractIntroductionSubsyndromal delirium (SSD) complicates diagnosis of delirium and dementia, although there is little research comparing their symptom profiles.MethodsCross-sectional study of 400 elderly patients' admission to a general hospital or nursing home diagnosed with delirium, SSD, dementia, or no-delirium/no-dementia (NDND). Symptom profiles were assessed using the Delirium Rating Scale-Revised-98 (DRS-R98).ResultsTwenty percent patients had delirium, 19.3% had SSD, 29.8% had dementia-only, and 31% had NDND. Eighty-one percent of subsyndromal and 76% of delirium groups had comorbid dementia. DRS-R98 scores showed ascending severity from NDND < dementia-only < SSD < delirium. DRS-R98 scores for items evaluating the three core symptom domains (cognitive, higher-order thinking, and circadian) distinguished SSD from delirium and both from nondelirium groups. DRS-R98 profiles were essentially the same in delirium and SSD subgroups with or without dementia, although total scale scores were generally higher when in comorbid subgroups.DiscussionSSD shared characteristic core domain symptoms with delirium, which distinguished each from nondelirium groups, although severity was intermediate in the subsyndromal group. Delirium core symptoms overshadowed the dementia phenotype when comorbid. Milder disturbances of delirium core domain symptoms are highly suggestive of SSD
Sustainable decommissioning of an offshore wind farm
No full textAbstractThe offshore wind industry has historically focused on setting up new projects, with the decommissioning phase receiving little attention. This can cause future problems as decommissioning needs to be planned at the beginning to prevent complications that may arise, as it implies important operations and high costs. There are numerous features that make decommissioning a challenge, such as the marine environment, the technical limitations of vessels and the lack of specific regulations that determine what should be done, increasing the uncertainty of the process. Additionally, the unique characteristics of the sites involve exclusive optimal solutions for each project. This article analyses the main operation parameters that affect the decommissioning process, identifying the benefits and drawbacks of the influencing variables. A model is designed to compare different transportation strategies, searching for cost reduction. A decommissioning methodology is been proposed based on this analysis, taking into consideration the technical aspects of the process, and minimising environmental impacts. The model forecasts that the predicted duration and costs of this process are not being adequately captured in site decommissioning plans
Thorium effect on the oxidation of uranium: Photoelectron spectroscopy (XPS/UPS) and cyclic voltammetry (CV) investigation on (U1−xThx)O2 (x=0 to 1) thin films
No full textAbstractThin films of U1−xThxO2 (x=0 to 1) have been deposited via reactive DC sputter technique and characterized by X-ray/Ultra-violet Photoelectron Spectroscopy (XPS/UPS), X-ray Powder Diffractometer (XRD) and Cyclic Voltammetry (CV) in order to understand the effect of Thorium on the oxidation mechanism. During the deposition, the competition between uranium and thorium for oxidation showed that thorium has a much higher affinity for oxygen. Deposition conditions, time and temperature were also the subject of this study, to look at the homogeneity and the stability of the films. While core level and valence band spectra were not altered by the time of deposition, temperature was affecting the oxidation state of uranium and the valence band due to the mobility increase of oxygen through the film. X-ray diffraction patterns, core level spectra obtained for U1−xThxO2 versus the composition showed that lattice parameters follow the Vegard's law and together with the binding energies of U-4f and Th-4f are in good agreement with literature data obtained on bulk compounds. To study the effect of thorium on the oxidation of U1−xThxO2 films, we used CV experiments at neutral pH of a NaCl solution in contact with air. The results indicated that thorium has an effect on the uranium oxidation as demonstrated by the decrease of the current of the oxidation peak of uranium. XPS measurements made before and after the CV, showed a relative enrichment of thorium at the extent of uranium at the surface supporting the formation at a longer term of a thorium protective layer at the surface of uranium-thorium mixed oxide
Treatment of post-traumatic elbow deformities in children with the Ilizarov distraction osteogenesis technique
No full textAbstractObjectiveThe present study assessed functional and radiographic outcomes of distraction osteogenesis treatment of post-traumatic elbow deformities in children.MethodsEight children were treated between 2008 and 2013 for post-traumatic elbow deformities using distraction osteogenesis. Mean age at time of operation was 10.9 years. Six patients had varus and 2 had valgus deformity. Magnitude of correction, fixator index, complications, carrying angle, and elbow range of motion were assessed. Functional results were graded according to protocol of Bellemore et al.ResultsMean follow-up was 43 months. Mean preoperative varus deformity in 6 patients was 29.2° and valgus deformity in 2 patients was 28.5°. Preoperative flexion and extension of elbow were 123.8° and −10.6°, respectively. Mean carrying angle was 9° valgus at last follow-up. Mean flexion and extension were 134.4° and −6.0°, respectively. Change in carrying angle was statistically significant (p = 0.002). There were 2 grade 1 pin tract infections and 1 diaphyseal fracture of humerus. Functional outcome was rated excellent in 7 patients and good in 1 patient.ConclusionIlizarov distraction osteogenesis is a valuable alternative in treatment of elbow deformities in children. The surgical technique is simple and correction is adjustable. Gradual correction prevents possible neurovascular complications and minimally invasive surgery produces less scarring. Compliance of patient and family is key factor in the success of the outcome.Level of evidenceLevel IV, therapeutic stud
Actually existing silk roads
No full textAbstractThis article explores the relevance of the concept of Silk Road for understanding the patterns of trade and exchange between China, Eurasia and the Middle East. It is based on ethnographic fieldwork in the city of Yiwu, in China's Zhejiang Province. Yiwu is a node in the global distribution of Chinese ‘small commodities’ and home to merchants and traders from across Asia and beyond. The article explores the role played by traders from Afghanistan in connecting the city of Yiwu to markets and trading posts in the world beyond. It seeks to bring attention to the diverse types of networks involved in such forms of trade, as well as their emergence and development over the past thirty years
Burning velocity and Markstein length blending laws for methane/air and hydrogen/air blends
No full textAbstractBecause of the contrasting chemical kinetics of methane and hydrogen combustion, the development of blending laws for laminar burning velocity, ul, and Markstein length for constituent mixtures of CH4/air and H2/air presents a formidable challenge. Guidance is sought through a study of analytical expressions for laminar burning velocity. For the prediction of burning velocities of blends, six blending laws were scrutinised. The predictions were compared with the measured burning velocities made by Hu et al. under atmospheric conditions [1]. These covered equivalence ratios ranging from 0.6 to 1.3, and the full fuel range for H2 addition to CH4. This enabled assessments to be made of the predictive accuracy of the six laws. The most successful law is one developed in the course of the present study, involving the mass fraction weighting of the product of ul, density, heat of reaction and specific heat, divided by the thermal conductivity of the mixture. There was less success from attempts to obtain a comparably successful blending law for the flame speed Markstein length, Lb, despite scrutiny of several possibilities. Details are given of two possible approaches, one based on the fractional mole concentration of the deficient reactant. A satisfactory empirical law employs mass fraction weighting of the product ulLb