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991.
Selectivity sequences and sorption capacities of phosphatic clay and humus rich soil towards the heavy metals present in zinc mine tailing 总被引:1,自引:0,他引:1
Sorption efficacy of phosphatic clay and humus rich soil alone and on combination were tested towards heavy metals present in zinc mine tailing (Zawar Zinc Mine), Udaipur (India). Characterization of the zinc mine tailing sample indicated the presence of Pb, Cu, Zn and Mn in the concentration of 637, 186, 720 and 577microg(-1), respectively. For sorption efficacy, the zinc mine tailing soil were properly amended with phosphatic clay and humus rich soil separately and in combination and leachability study was performed by batch experiment at different pH range from 3 to 9. The data showed that the percent leachability of heavy metal in non-amended soil was 75-90%. After amendment with phosphatic clay percent leachability of heavy metals became 35-45%. Further, the addition of humus soil to phosphatic clay decreased the percent leachability up to 5-15% at all tested pH. Column leachability experiment was performed to evaluate the rate of leachability. The shape of cumulative curves of Pb, Cu, Zn and Mn showed an increase in its concavity in following order: PbCu>Zn>Mn. Further, Langmuir isotherms applied for the sorption studies indicated that phosphatic clay in the presence of humus soil had high affinity for Pb followed by Cu, Zn and Mn, with sorption capacities (b) 139.94, 97.02, 83.32 and 67.58microgg(-1), respectively. 相似文献
992.
Qin Zhang Sangsu Bang Sharat Chandra Ru-Rong Ji 《International journal of molecular sciences》2022,23(22)
Inflammation is known to cause pain, and pain is of one of the cardinal signs of inflammation. Mounting evidence suggests that acute inflammation also resolves pain through specialized pro-resolving mediators (SPMs) and macrophage signaling. GPR37 is expressed by neurons and oligodendrocytes in the brain and has been implicated in multiple disorders, such as demyelination, Parkinson’s disease, stroke, and cancer. Recent studies have demonstrated that GPR37 is expressed by macrophages and confers protection against infection by bacteria and parasites. Furthermore, GPR37 promotes the resolution of inflammatory pain and infection-induced pain, as the duration of pain after tissue injury and infection is prolonged in mice lacking Gpr37. Mechanistically, activation of GPR37 enhances macrophage phagocytosis, and Gpr37-deficient macrophages exhibit dysregulations of pro-inflammatory and anti-inflammatory cytokines, switching from M2- to M1-like phenotypes. We also discuss novel ligands of GPR37, including neuroprotectin D1 (NPD1), a SPM derived from docosahexaenoic acid (DHA), and bone-derived hormone osteocalcin (OCN), which can suppress oligodendrocyte differentiation and myelination. NPD1 stimulates macrophage phagocytosis via GPR37 and exhibits potent analgesic actions in various animal models of inflammatory and neuropathic pain. Targeting GPR37 may lead to novel therapeutics for treating inflammation, infection, pain, and neurological diseases. 相似文献
993.
Sankata Bhanjan Prusty Sridhar Seshagiri Umesh Chandra Pati Kamala Kanta Mahapatra 《IEEE/CAA Journal of Automatica Sinica》2020,7(1):118-125
For the problem of set point regulation of the liquid level in coupled tank systems, we present a continuous sliding mode control(SMC) with a "conditional integrator", which only provides integral action inside the boundary layer. For a special choice of the controller parameters, our design can be viewed as a PID controller with anti-windup and achieves robust regulation.The proposed controller recovers the transient response performance without control chattering. Both full-state feedback as well as output-feedback designs are presented in this work. Our output-feedback design uses a high-gain observer(HGO) which recovers the performance of a state-feedback design where plant parameters are assumed to be known. We consider both interacting as well as non-interacting tanks and analytical results for stability and transient performance are presented in both the cases. The proposed controller continuous SMC with conditional integrators(CSMCCI) provides superior results in terms of the performance measures as well as performance indices than ideal SMC, continuous SMC(CSMC) and continuous SMC with conventional integrator(CSMCI). Experimental results demonstrate good tracking performance in spite of unmodeled dynamics and disturbances. 相似文献
994.
Layne Christopher M.; Ippen Chandra Ghosh; Strand Virginia; Stuber Margaret; Abramovitz Robert; Reyes Gilbert; Jackson Lisa Amaya; Ross Leslie; Curtis Amy; Lipscomb Laura; Pynoos Robert 《Canadian Metallurgical Quarterly》2011,3(3):243
Recognition of the nationwide high prevalence of psychological trauma in children and adolescents, combined with increasing awareness of the far-reaching adverse consequences of childhood trauma, have led to calls to develop a trauma-informed mental health workforce. We describe the initial pilot test of the Core Concepts portion of the Core Curriculum on Childhood Trauma, as conducted in a large graduate school of social work. The Core Curriculum uses detailed case vignettes of trauma-exposed youth and families, combined with problem-based learning methods, to promote two primary learning aims: (a) to enhance the development of foundational trauma-related conceptual knowledge, and (b) to accelerate the acquisition of trauma-informed clinical reasoning and clinical judgment. Vignettes are presented in segments to simulate gathering, organizing, drawing meaning from, and making decisions based on information in professional practice. After each segment, the facilitator helps learners to summarize relevant facts, develop hunches and hypotheses, identify learning issues, and plan next steps. The Curriculum was very favorably received by students and was associated with marked increases in self-efficacy in applying the Core Concepts to work with trauma-exposed youth and families. We discuss ways in which the Curriculum can be used, especially as a foundation for training in specific evidence-based treatment protocols, to help prepare a national mental health workforce capable of implementing trauma-informed evidence-based practice. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
995.
This article addresses the problem of determining the 3-dimensional locations of salient points in the environment of a moving camera based on a monocular image sequence obtained by the camera. The camera's translational and rotational velocities are assumed to be known approximately via inertial sensors. The motion of the camera is represented by a constant velocity model. Salient points in the image sequence are extracted using Gabor wavelets and tracked using labeled graph matching. The 3-D positions of the selected environmental points relative to the camera are then estimated recursively using an extended Kalman filter (EKF), after initialization by two-frame motion stereo. The motion parameters of the camera are also refined simultaneously. Experimental results on real data are given. © 1992 John Wiley & Sons, Inc. 相似文献
996.
Chandra K. Jaggi Aditi Khanna Priyanka Verma 《International journal of systems science》2013,44(7):1185-1196
In today's business transactions, there are various reasons, namely, bulk purchase discounts, re-ordering costs, seasonality of products, inflation induced demand, etc., which force the buyer to order more than the warehouse capacity. Such situations call for additional storage space to store the excess units purchased. This additional storage space is typically a rented warehouse. Inflation plays a very interesting and significant role here: It increases the cost of goods. To safeguard from the rising prices, during the inflation regime, the organisation prefers to keep a higher inventory, thereby increasing the aggregate demand. This additional inventory needs additional storage space, which is facilitated by a rented warehouse. Ignoring the effects of the time value of money and inflation might yield misleading results. In this study, a two-warehouse inventory model with linear trend in demand under inflationary conditions having different rates of deterioration has been developed. Shortages at the owned warehouse are also allowed subject to partial backlogging. The solution methodology provided in the model helps to decide on the feasibility of renting a warehouse. Finally, findings have been illustrated with the help of numerical examples. Comprehensive sensitivity analysis has also been provided. 相似文献
997.
Abhijit Chandra Grant Anderson Shreyes Melkote Wei Gao Han Haitjema Konrad Wegener 《CIRP Annals》2014,63(2):797-819
Solar cells gained significant interest recently due to the rapid increase in fossil fuel costs and renewed attention to sustainability. The effectiveness of a solar cell in energy harvesting hinges on three key characteristics: efficiency of energy conversion, reliability and life expectancy, and cost. All three attributes are critically influenced by surface and interface properties inherent in the design and manufacture of these devices. This paper starts with an exposition of solar cell manufacturing, followed by discussion of efficiency enhancement, reliability issues, and cost and energy footprint reduction. The role of surface and interface modifications in realizing such improvements is assessed. 相似文献
998.
Arbaz Khan Pravir Dutt Chandra Shekhar Upadhyay 《Journal of scientific computing》2017,73(2-3):876-905
In this paper, a least-squares spectral element method for parabolic initial value problem for two space dimension on parallel computers is presented. The theory is also valid for three dimension. This method gives exponential accuracy in both space and time. The method is based on minimization of residuals in terms of the partial differential equation and initial condition, in different Sobolev norms, and a term which measures the jump in the function and its derivatives across inter-element boundaries in appropriate fractional Sobolev norms. Rigorous error estimates for this method are given. Some specific numerical examples are solved to show the efficiency of this method. 相似文献
999.
Molecular identification and characterization of Fusarium spp. associated with sorghum seeds
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1000.
The development of tissue engineering in the field of orthopedic surgery is booming. Two fields of research in particular have emerged: approaches for tailoring the surface properties of implantable materials with osteoinductive factors as well as evaluation of the response of osteogenic cells to these fabricated implanted materials (hybrid material). In the present study, we chemically grafted insulin onto the surface of hydroxyapatite nanorods (nHA). The insulin-grafted nHAs (nHA-I) were dispersed into poly(lactide-co-glycolide) (PLGA) polymer solution, which was electrospun to prepare PLGA/nHA-I composite nanofiber scaffolds. The morphology of the electrospun nanofiber scaffolds was assessed by field emission scanning electron microscopy (FESEM). After extensive characterization of the PLGA/nHA-I and PLGA/nHA composite nanofiber scaffolds by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction spectroscopy (XRD), X-ray photoelectron spectroscopy (XPS), energy-dispersive X-ray spectrometry (EDS), and transmission electron microscopy (TEM), the PLGA/nHA-I and PLGA/nHA (used as control) composite nanofiber scaffolds were subjected to cell studies. The results obtained from cell adhesion, alizarin red staining, and Von Kossa assay suggested that the PLGA/nHA-I composite nanofiber scaffold has enhanced osteoblastic cell growth, as more cells were proliferated and differentiated. The fact that insulin enhanced osteoblastic cell proliferation will open new possibilities for the development of artificial scaffolds for bone tissue regeneration. 相似文献