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This article, titled "The Many Avatars of Knee Osteosarcoma," discusses the various radiologic appearances of osteosarcoma (OS), a type of bone tumor. The authors conducted a retrospective analysis of 24 biopsy-proven cases of OS over a two-year period. They found that OS can have atypical manifestations that resemble other benign or malignant conditions, such as fibrous dysplasia, aneurysmal bone cyst, chondroblastoma, and osteomyelitis. The article provides detailed descriptions of the different radiologic features of OS, which can aid in accurate diagnosis and treatment decisions. [Extracted from the article]

This article emphasizes the importance of using conventional radiography in diagnosing and monitoring metaphyseal pathologies of the knee joint in pediatric patients. The authors evaluated 25 pediatric knee radiographs and categorized the metaphyseal abnormalities into different groups based on their characteristics. They found that radiographs can provide valuable information for diagnosing various conditions, such as dysplasias, rickets, and neoplastic etiologies. While radiography alone may not be sufficient in some cases, it can help form a preliminary opinion and eliminate the need for further evaluation in many pathologies. [Extracted from the article]

Polycrystalline Sm0.55Sr0.45MnO3 (SSMO) thin films (thickness ~ 100 nm) were prepared on nearly lattice matching LSAT (100) single crystal substrates by ultrasonic nebulized spray pyrolysis, and impact of oxygen vacancy on magnetic and high field magneto-transport properties are investigated. The X-ray diffraction θ‒2θ scan reveals that these films (i) have very good crystallinity, (ii) oriented along out-of-plane c-direction, and (iii) are under small tensile strain. The impact of oxygen vacancy results into (i) higher value of paramagnetic insulator (PMI) to ferromagnetic metal (FMM) transition temperature, i.e., TC/TIM, (ii) sharper PMI–FMM transition, as confirmed by higher temperature coefficient of resistance (TCR), (iii) higher value of magnetization and magnetic saturation moment, and (iv) higher value of magnetoresistance. The magnetic state at T < TC is akin to cluster glass, which is formed by the presence of charge-ordered–antiferromagnetic clusters in the ferromagnetic matrix. We suggest here that oxygen vacancy favors ferromagnetic metal phase while oxygen vacancy annihilation leads to antiferromagnetic–charge-ordered insulator phase. The observed results have been explained in terms of the growth condition-induced variations in the dimensionality and fractions of the competing ferromagnetic metal and antiferromagnetic–charge-ordered insulator phases. [ABSTRACT FROM AUTHOR]

• REE double sulfates were prepared from NiMH waste. • In-situ conversion to hydroxides and cerium oxidation was performed. • Limited conversion was observed with high L/S ratio. • The mixed hydroxide-oxide was characterized. Efficient recovery of REEs present in the battery waste is a modern problem that has proven to be difficult to solve in an efficient manner. The raw material investigated in the current study is mixed alkaline rare earth element (REE) double sulfate (DS) precipitate, originating from the sulfuric acid leachate of nickel-metal hydride battery (NiMH) waste. Typically, REE can be precipitated as a mixture of REE double sulfates, however the real challenge is the separation of REEs from each other's into pure fraction. The study elucidates the process by which the DS are transformed into hydroxides with simultaneous in-situ conversion of Ce(III) to Ce(IV) by air. Air flow rate (0–1 L/h), temperature (30–60 °C), liquid-solid ratio (L/S, 12.5–100 g/L), 3REE/NaOH mol ratio (1–1.6) and time (60–240 min) were varied in the study of oxidation and double sulfate conversion. Best oxidation achieved was 93% along near-complete dissociation of double sulfate matrix (52767 ppm Na reduced to 48 ppm Na). After parameter optimization, a larger batch was produced to conduct selective dissolution of REE(III) into HNO 3 media, leaving concentrated impure Ce(OH) 4 as the end product. [ABSTRACT FROM AUTHOR]

Solvent extraction of yttrium (Y) from different aqueous solutions using the organic extractant 2- ethylhexyl phosphonic acid mono-2-ethylhexyl ester (PC88A) diluted in kerosene was investigated. Solution chemistry considerations were proposed to identify the predominant species in different aqueous media (H2SO4, HCl and HNO3). In general, nitric and hydrochloric acids were found to be more efficient than sulfuric acid for yttrium extraction. Separation studies showed that nitric acid provide higher separation of Y(III) from light REES while sulfuric acid works better when separation of Y(III) from heavy REEs is desired. [ABSTRACT FROM AUTHOR]

Solvent extractions of europium (Eu(III)) from hydrochloric acid solutions using 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (PC88A) and Cyanex 572 (chemical structure not reported) diluted in kerosene are compared and discussed. Pourbaix and speciation diagrams for Eu(III) in chloride solutions are presented to clarify the chemistry of solution at different acidities and chloride concentrations. Preliminary structures, energies and free energies of Eu(III) species in both aqueous and organic phases (the latter consisting of phosphonic acid in heptane) were calculated and compared using molecular modeling. The effects of pH (1–5), extractant concentration (1–100 mM) and ionic strength (0.05–1 M) are studied to systematically characterize the extraction behavior of Eu(III) and, based on these results, an extraction mechanism is suggested. It is found that under similar experimental conditions a higher extent of extraction is obtained with PC88A compared with Cyanex 572. The infrared spectra of the loaded organic solutions support the hypothesis that the Eu(III) extraction reaction is driven by a cation exchange mechanism. Separation studies of Eu(III) from other rare earth elements (REEs) were also carried out and revealed that PC88A provides higher separation of Eu(III) from light REEs while Cyanex 572 achieves higher separation from heavy REEs. [ABSTRACT FROM AUTHOR]

A simple theoretical model has been developed for the solvent extraction of cations with different oxidation states varying from +1 to +4 using acidic extractants. The basic assumption behind this theoretical model is that the cationic species (M n+ ) will exist in ionic form and not form any complexes in the aqueous phase. A direct relationship between the concentration of metal ions in the aqueous phase and that in the organic phase was developed for trivalent and tetravalent cationic species. Using this model, the distribution isotherms were plotted for a given set of conditions. The effect of pH and equilibrium constant on the distribution isotherms were represented in three-dimensional form for trivalent and tetravalent cationic species. Consistent with expectations, the results suggest that with increasing pH and an increasing equilibrium constant one finds an enhancement of the extraction of cationic species for a given set of conditions. The calculations were performed in the pH range of 1 through 3 because for higher pH values, the pH shift accompanying the extraction is significant and thereby affects the mass balance equations. A comparison of the distribution isotherms shows that the total metal ion concentration to extractant concentration ratio determines the distribution behavior of metal ions with different valency. At low total metal ion concentration to extractant concentration ratio, the distribution coefficient was higher for higher oxidation state cations under similar experimental conditions, and this trend started to reverse when the total metal ion concentration to extractant concentration ratio was increased. [ABSTRACT FROM AUTHOR]

In this article, an attempt is made to develop a 3D gas–solid fluidized bed reactor (FBR). Basically, it deals with simulation of a FBR in computational fluid dynamics (CFD) using the software, Ansys Fluent v14. The simulation of gas–solid flow is carried out using Eulerian multifluid model which is integrated with the solid particle kinetic theory. The coefficients of exchange momentum are estimated using the Syamlal & O'Brien, Gidaspow, Wen-Yu, and Huilin–Gidaspow drag functions. The results of the simulation have been validated with the experimental data available in literature and had proven that the model is capable to predict the hydrodynamics of FBR. The variation in kinetic energy of the solid phase is calculated by varying the restitution coefficient (RC) from 0.90 to 0.99. The predictions of pressure drop compare excellently with the experimental data. Finally, the effect of particle diameter on the expanded bed height has been studied for FBR. [ABSTRACT FROM AUTHOR]

In this paper, an attempt has been made to develop a 3-D simulation model for biomass gasification of pine sawdust in a fluidized bed reactor (FBR), solved using ANSYS Fluent v14. The predictions have been compared to the experimental data available in the literature, which proves that the model is well capable of studying the heat transfer and hydrodynamics of FBRs. Further, the effects of superficial gas velocity ratio (u/umf), bed porosity, static bed height, and particle diameter on pressure drop, and bed expansion ratio (H/HO), solid volume fraction, and gas–solid temperature with respect to bed height have been investigated. [ABSTRACT FROM PUBLISHER]

Aim: To evaluate the effect of antecedent antimicrobial therapy on diagnostic yield from percutaneous image-guided disc-space sampling.Materials and Methods: A retrospective review of the electronic health records of all patients who underwent image-guided percutaneous sampling procedures for suspected discitis/osteomyelitis over a 5-year period was performed. One hundred and twenty-four patients were identified. Demographics, medical history, and culture results were recorded as well as duration of presenting symptoms and whether antecedent antibiotic therapy had been administered.Results: Of the 124 patients identified who underwent image-guided percutaneous disc-space sampling, 73 had received antecedent antibiotic treatment compared with 51 who had not. The overall positive culture rate for the present study population was 24% (n=30). The positive culture rate from patients previously on antibiotics was 21% (n=15) compared with 29% (n=15) for patients who had not received prior antibiotic treatment, which is not statistically significant (p=0.26). Eighty-six percent (n=63) of patients who had antecedent antibiotics received treatment for 4 or more days prior to their procedure, whereas 14% (n=10) received treatment for 1-3 days prior to their procedure. The difference in culture positivity rate between these two groups was not statistically significant (p=0.43). Culture results necessitated a change in antibiotic therapy in a third of the patients who had received antecedent antibiotic therapy.Conclusion: Antecedent antibiotic therapy, regardless of duration, did not result in significantly diminished diagnostic yield from percutaneous sampling for suspected discitis/osteomyelitis. The present results suggest that percutaneous biopsy may nonetheless yield positive diagnostic information despite prior antimicrobial therapy. If the diagnostic information may impact choice of therapeutic regimen, percutaneous biopsy should still be considered in cases where there is a history of prior antimicrobial therapy. [ABSTRACT FROM AUTHOR]

Transparent and conductive Al doped zinc oxide (AZO) films were reactively sputtered from metallic targets onto macroporous silicon (MPS) substrate to fabricate a heterojunction interface structure. A tungsten oxide (WO3) thin film was placed between metallic aluminum back contact and bulk silicon to extract photogenerated holes from the absorber. Due to the susceptibility of PS to naturally oxidize over the period of time, a thin film of SiO2 was thermally grown to stabilize the electrical response of the junction. Such thin layer acts as passive film to prevent recombination and is placed between the p-n junction. Photovoltaic properties of this heterojunction were studied by using the current density-voltage (J-V) measurement under AM 1.5 illumination. The experimental results show an increase in photovoltaic performance of AZO/MPS solar cell with a buffer layers of WO3. Such heterostructures are promising for the development of the low-cost, clean, and durable devices with appreciable light-to-electricity conversion efficiency. [ABSTRACT FROM AUTHOR]

Highlights: [•] WO3/PS composite results in an increase in effective surface area of WO3. [•] Temperature dependence of PL shows annihilation/enhancement of signal in air/N2. [•] Rectifying behavior of WO3/PS decreases by ∼7 times after annealing under N2. [•] Potential applications: increase in sensing/catalytic performance of WO3 and LEDs. [ABSTRACT FROM AUTHOR]

Highlights: [•] We model heat conduction in a composite slab using 1-D approach. [•] Comparisons have been made between results from 1-D and 2-D simulation. [•] Applicability of 1-D model is assessed for block with inserts of dissimilar materials. [•] Present approach can help in developing optimum shape of composite bricks. [ABSTRACT FROM AUTHOR]

Painful vertebral body hemangiomas have been successfully treated with vertebroplasty and kyphoplasty. Sacral hemangiomas are uncommon and as such painful sacral hemangiomas are rare entities. We report what we believe is only the second successful treatment of a painful sacral hemangioma with CT-guided sacroplasty. A 56-year-old woman with a history of rightsided total hip arthroplasty and lipoma excision presented to her orthopedic surgeon with persistent right-sided low back pain which radiated into her buttock and right groin and hindered her ability to walk and perform her activities of daily living. MRIs of the thoracic spine, lumbar spine and pelvis showed numerous lesions with imaging characteristics consistent with multiple hemangiomas including a 2.2½2.1 cm lesion involving the right sacrum adjacent to the right S1 neural foramen. Conservative measures including rest, physical therapy, oral analgesics and rightsided sacroiliac joint steroid injection did not provide significant relief. Given her lack of improvement and the fact that her pain localized to the right sacrum, the patient underwent CT-guided sacroplasty for treatment of a painful right sacral hemangioma. Under CT fluoroscopic guidance, a 10 gauge introducer needle was advanced through the soft tissues of the back to the margin of the lesion. Biopsy was then performed and after appropriate preparation, cement was then introduced through the needle using a separate cement filler cannula. Appropriate filling of the right sacral hemangioma was visualized using intermittent CT fluoroscopy. After injection of approximately 2.5 cc of cement, it was felt that there was near complete filling of the right sacral hemangioma. With satisfactory achievement of cement filling, the procedure was terminated. Pathology from biopsy taken at the time of the procedure was consistent with hemangioma. Image-guided sacroplasty with well-defined endpoints is an effective, minimally invasive and safe procedure. Patients with painful sacral hemangiomas can be treated with this technique with no significant complications. [ABSTRACT FROM AUTHOR]

Calcified thoracic intradural disc herniations have recently been reported as a cause of spontaneous intracranial hypotension (SIH). We report successful treatment of SIH with a targeted CT-guided epidural blood patch. A 57-year-old man presented to the emergency department with a two-week history of progressively debilitating headache. CT and MRI of the brain showed findings consistent with intracranial hypotension and MRI of the spine showed findings consistent with CSF leak. Subsequent CT myelogram of the thoracic spine confirmed the presence of CSF leak and calcified disc herniations at the T6-7, T7-8 and T8-9 levels indenting the ventral dura and spinal cord. The calcified disc herniation at T6-7 had an intradural component and was therefore the most likely site of the CSF leak. Under CT fluoroscopic guidance, a 20-gauge Tuohy needle was progressively advanced into the dorsal epidural space at T6-7. After confirmation of needle tip position, approximately 18cc of the patient’s own blood was sterilely removed from an arm vein and slowly re-injected into the dorsal epidural space. With satisfactory achievement of clot formation, the procedure was terminated. The patient tolerated the procedure well. The next morning, his symptoms had completely resolved and he was neurologically intact. At five-week follow up, he was symptom-free. Targeted epidural blood patch at the site of presumed CSF leak can be carried out in a safe and effective manner using CT fluoroscopic guidance and can be an effective alternative to open surgical management in selected patients. [ABSTRACT FROM AUTHOR]

Few controlled trials compared second-generation antipsychotics (SGAs) with first-generation antipsychotics (FGAs) regarding relapse prevention in schizophrenia. We conducted a systematic review/meta-analysis of randomized trials, lasting 6 months comparing SGAs with FGAs in schizophrenia. Primary outcome was study-defined relapse; secondary outcomes included relapse at 3, 6 and 12 months; treatment failure; hospitalization; and dropout owing to any cause, non-adherence and intolerability. Pooled relative risk (RR) (±95% confidence intervals (CIs)) was calculated using random-effects model, with numbers-needed-to-treat (NNT) calculations where appropriate. Across 23 studies (n=4504, mean duration=61.9±22.4 weeks), none of the individual SGAs outperformed FGAs (mainly haloperidol) regarding study-defined relapse, except for isolated, single trial-based superiority, and except for risperidone's superiority at 3 and 6 months when requiring ≥3 trials. Grouped together, however, SGAs prevented relapse more than FGAs (29.0 versus 37.5%, RR=0.80, CI: 0.70-0.91, P=0.0007, I2=37%; NNT=17, CI: 10-50, P=0.003). SGAs were also superior regarding relapse at 3, 6 and 12 months (P=0.04, P<0.0001, P=0.0001), treatment failure (P=0.003) and hospitalization (P=0.004). SGAs showed trend-level superiority for dropout owing to intolerability (P=0.05). Superiority of SGAs regarding relapse was modest (NNT=17), but confirmed in double-blind trials, first- and multi-episode patients, using preferentially or exclusively raw or estimated relapse rates, and for different haloperidol equivalent comparator doses. There was no significant heterogeneity or publication bias. The relevance of the somewhat greater efficacy of SGAs over FGAs on several key outcomes depends on whether SGAs form a meaningful group and whether mid- or low-potency FGAs differ from haloperidol. Regardless, treatment selection needs to be individualized considering patient- and medication-related factors. [ABSTRACT FROM AUTHOR]

A cross sectional study was conducted during May-June 2010 among woman of reproductive age group (15-45 years) in the urban and the rural areas of Bareilly District to asses the level of awareness regarding RTIs/STDs. The two stage cluster sampling technique was adopted. A structured questionnaire was used to interview the study participants during the house to house surveys. Each woman of reproductive age of selected household was interviewed in private about her reproductive history, current knowledge, source of information and modes of transmission of RTIs/STDs. Statistical analysis was done with Epi Info computer software. Standard Normal Variate (SNV) Test for comparison of two groups' proportion was done; z and p were calculated to know the significance of the proportions of two groups for comparison. Most of the women were aware of RTIs/STDs (80.32%) in urban areas whereas only 27.41% in rural areas were aware of these diseases. The television and radio was the main source of information in both rural (41.17% & 32.94%) and urban areas (TV-90.36%, Radio-48.19%). [ABSTRACT FROM AUTHOR]

A fluidized motion conveying system (FMCS) that conveys particulate material over a distance of 7.5 m was developed to investigate the influence of operating parameters on the material mass flow rate and bed depth. The effect of channel length (varied over 7.5 m, 5.5 m, and 3.7 m) was also investigated in relation to the observed variables. It is found that, for a given superficial air velocity, increase in conveying distance reduces the channel conveying capacity at all conveyor inclinations. The effect of superficial air velocity and channel inclination on material mass flow rate and bed depth, however, remains the same as reported earlier for 3.7 m channel length. The predicted material mass flux and operating superficial air velocity did not agree with the experimental data, thus, the empirical relations applicable to the design of air gravity conveyors for optimum yield were not valid for the design of FMCS. [ABSTRACT FROM AUTHOR]

Emphasis of the present work is on an elegant real-time solution for GPS/INS integration. Micro-electro mechanical system (MEMS) based inertial sensors are light but not accurate enough for inertial navigation system (INS) applications. An integrated INS/GPS system provides better accuracy compared with either INS or GPS, used individually. This paper describes an improved design and fabrication of a loosely coupled INS-GPS integrated system. The systems currently available use commercial off-the-shelf (COTS) hardware and are, therefore, not optimized for compact, single supply, and low power requirements. In the proposed system, a digital signal processor (DSP) is used for inertial navigation solution and Kalman filter computations. A field programmable gate array (FPGA) is used for creating an efficient interface of the GPS with the DSP. Direct serial interface of the GPS involve tedious processing overhead on the navigation processor. Therefore, a universal asynchronous receiver transmitter (UART) and dual port random axis memory (DPRAM) are created on the FPGA itself. This also reduces the total chip count, resulting in a compact system. The system is designed to give real time processed navigation solutions with an update rate of 100 Hz. All the details of this work are presented. [ABSTRACT FROM AUTHOR]

Disease-modifying antirheumatic drugs (DMARDs) improve the disability and slow the progression of the joint damage in rheumatoid arthritis (RA). However, a large proportion of patients experience inefficacy by the end of 2 years. This loss of efficacy may be due to expression of multidrug resistance (MDR) proteins on lymphocytes. The objective is to study the expression of MDR protein on the peripheral blood lymphocytes in patients with RA and correlate it with the disease status and response to treatment. Twenty-eight patients were enrolled. Expression of MDR-1 by flow cytometry was carried out on lymphocytes at baseline and after 4 months of therapy. This expression was correlated with disease activity scores (DAS 28). There were 25 females with mean age of 48.13 years and median disease duration of 48 months. Eighteen patients were DMARD naive and ten were refractory to DMARD (methotrexate). The percentage of cells expressing MDR-1 in the DMARD-naive ( p < 0.O5) and DMARD-refractory ( p < 0.05) groups were significantly higher than the healthy controls at the baseline. The relative fluorescence intensity was significantly higher in the DMARD-refractory group ( p < 0.05) as compared to the DMARD-naive group. After 4 months of therapy, there was significant improvement in the D value ( p < 0.01) in the DMARD-naive group (treated with methotrexate only) and DMARD-refractory group ( p < 0.05). A significant correlation ( r = 0.563) between the DAS 28 scores and the D value ( p = 0.003) was observed. Expression of MDR-1 in RA correlated with disease activity status and improved with DMARD therapy. It is not related to the refractoriness to therapy with methotrexate. [ABSTRACT FROM AUTHOR]

A series of fullerene [60]-polyacrylic acid (C60-PAA) conjugates was synthesized through 2,2-azobisisobutyronitrile (AIBN)-initiated in situ polymerization of acrylic acid (AA) under different reaction conditions in supercritical (carbon dioxide (scCO2). This has afforded corresponding C60-PAA conjugates with C60 content ranging from 0.76 to 6.69% and rheoviscosity from 1.183 to 2.349 Mpas (means—in this investigation, fullerene [60] content varied from 0.76 (minimum) to 6.69% (maximum) in synthesized C60-PAA conjugates and rheoviscosity varied from 1.183 (minimum) to 2.349 Mpas (maximum value). The process of in situ polymerization was monitored at concentrations (mole/dL) of AIBN of 304.50-931.5 × 10-3 and AA of 6.94-20.82 × 10-3, temperatures of 50°-90°C, pressures of 1000-2600 psi, and times of 2-26 h. The progress of insitu polymerization was monitored rheoviscometrically in methanol at 25°±1°Cand by gel permeation chromatography. Selected C60-PAA conjugates were characterized by UV-vis, FT-IR, 1H NMR, laser-induced breakdown spectra (LIBS), transmission electron microscopy (TEM), and simultaneous thermogravimetric-differential thermogravimetric analysis-differential scanning calorimetry (TG-DTA-DSC) in nitrogen. [ABSTRACT FROM AUTHOR]

Extubation failure-need for reintubation within 72 h of extubation, is common in intensive care unit (ICU). It can cause increased morbidity, higher costs, higher ICU and hospital length of stay (LOS) and mortality. Patients with advanced age, high severity of illness at ICU admission and extubation, preexisting chronic respiratory and cardiovascular disorders are at increased risk of extubation failure. Unresolved illness, development and progression of organ failure during the time from extubation to reintubation and reintubation itself have been proposed as reasons for increased morbidity and mortality. Parameters used to predict extubation failure can be categorized into parameters assessing respiratory mechanics, airway patency and protection and cardiovascular reserve. Adequate cough strength, minimal secretions and alertness are necessary for successful extubation. Evidence suggests that early institution of non-invasive ventilation and prophylactic administration of methylprednisolone may prevent reintubation in some patients. The intensivist needs to identify patients at high risk of extubation failure and be prepared to reinstitute ventilation early to prevent adverse outcomes. [ABSTRACT FROM AUTHOR]

Buck converter is modelled as a hybrid automaton for the purpose of designing an appropriate control law to regulate its output voltage. The circuit when operated in continuous current mode is pulled into a limit cycle, specified by the regulation specifications, although the switching frequency varies with the load. On the other hand, under light-load conditions, the circuit is pulled into a fixed-frequency limit cycle in discontinuous current mode to satisfy the regulation criteria. Therefore, the controller design is generic in the sense that the required regulation is met throughout the operating range of the buck converter. The control problem is simplified as a guard selection problem and guards, defining the discrete states, are derived using a simple circuit theoretical approach, by imposing certain regulation and control constraints. Satisfactory operation of the buck converter under the proposed scheme is demonstrated using computer simulations and laboratory experiments. The suitability and simplicity of the proposed control scheme over a wide range of disturbances is highlighted. [ABSTRACT FROM AUTHOR]

Taylor bubbles rising through a vertical concentric annulus do not wrap around the inner tube completely. The two edges of the bubble are separated by a liquid bridge which increases with an increase of the inner radius. However, the change in the shape of the Taylor bubbles in annuli with extremely small inner diameter has not yet been reported. In the present investigation, several experiments have been performed in circular and noncircular annuli to understand the influence of the inner and outer wall on the bubble shape. The bubble has been observed to assume a completely different shape in both circular and square annuli with a very thin inner rod. Nevertheless, the rise velocity for such situations agree with the prediction of the model proposed by Das et al. [Chem. Eng. Sci. 53, 977 (1998)] when the outer pipe is circular but fails for a square outer pipe. [ABSTRACT FROM AUTHOR]

This work presents a comparison of various maximum power point tracking (MPPT) techniques applied to 1-φ, single-stage, grid-connected photovoltaic (PV) systems. A representative single-stage grid-connected PV system, based on buck-boost converter topology operating in discontinuous current mode (DCM) with sine-triangle pulse width modulation (SPWM) and feeding sinusoidal power into the grid, is considered for this study. MPPT techniques are compared on the basis of the time taken to reach (track) the MPP, operating point oscillations in the vicinity of MPP and the dependence of the algorithms, if any, on array configuration and parameters. Comparison is also made on the basis of the energy extracted from the PV source during the transient tracking phase. In this context, an energy tracking factor term (ETF) is introduced and defined. It is observed that all the MPPT schemes studied have their own merits and demerits. The ripple correlation and β methods offer an overall good combination of desirable features. All the results of this study are presented. [ABSTRACT FROM AUTHOR]

The impact of predatory, agroecosystem-nesting ant species on the larval stages of the two major lepidopteran pests, the diamondback moth (DBM), Plutella xylostella and the black cutworm (BC), Agrotis ipsilon, in cauliflower agroecosystem in Uttar Pradesh, India, was investigated in farmers’ fields. Field observations revealed that six ant species, the most important being Pheidole sp., preyed on the crop-damaging stages of DBM and BC. Bait experiments with larvae of DBM and BC, placed randomly on the ground, demonstrated significant active retrieval by Pheidole sp. Investigations on larval density of both the insect pests on cauliflower crops, located within 1–5 m distances from nests of Pheidole sp., revealed a significant increase in the level of infestation of the crop plants with increasing distance from the ant nests. While a significant negative correlation was found between infested plants with low larval densities, a positive correlation was found between plants with high larval densities with regard to the distance of crop plant location from the ant nest. Ant-inclusion and -exclusion experiments under field conditions further confirmed the role of predatory ants, with Pheidole sp. having the major impact in the direct retrieval of the lepidopteran larvae from the crop plants. A significant difference was found in the leaf area damaged by BC larvae between the ant-included and -excluded potted plants during the 6-h observation period. Thus, this study provides direct evidence of the role of ants in actively searching and directly preying on the larval stages of DBM and BC, on cauliflower plants. Moreover, we demonstrate that in ephemeral, annual cropping agroecosystems, predatory ants are important natural enemies of lepidopteran pests, playing a significant role in plant protection. [ABSTRACT FROM AUTHOR]

A time series analysis of various atmospheric as well as oceanic parameters derived from different satellites covering eastern Indian Ocean and Bay of Bengal has been carried out for the period December 2004 to February 2005. The purpose is to assess the likely perturbations in the air-sea exchanges associated with the tsunami event of 26 December 2004. Satellite derived sea level anomaly in the northern Bay of Bengal show a rise in the sea level of roughly about 5-6 cm after 26 December 2004. A significant cooling of the order of 0.5°C in a span of 5 days (21-27 December 2004) in the sea surface temperature (SST) is observed near Andaman and Nicobar Island. The formation of such anomalies is certainly associated with the rising of the sub-surface water towards surface due to the enhanced turbulent exchange. An enhanced turbidity near Sumatra seen in the MODIS colour data in the week following 26 December 2004 is also suggestive of turbulent mixing. After an initial dip in the integrated water vapour (IWV) on 27 December 2004, an apparent growth in the water vapour loading is observed in the Tropical Rainfall Measuring Mission/Microwave Imager (TMI) data from 31 December 2004 to 11 January 2005 near Andaman and Nicobar Island. An analysis of the boundary layer parameters suggests that the increased water vapour loading in the atmosphere following the tsunami is not due to the winds and neither due to the increase in SST. One of the possible reasons could be direct injection of water into the atmosphere. The study could be used as an indicative to understand changes in a global context under sea level rise scenario. [ABSTRACT FROM AUTHOR]

In this paper we report the detailed fabrication and experimental characterization of porous silicon one-dimensional photonic bandgap structures for specific photonic applications. These structures have been prepared on silicon substrate as well as free standing and can be proven useful for a large variety of applications such as high quality dielectric mirrors and filters. [ABSTRACT FROM AUTHOR]

Some aspects of the principal stretch and strain invariants, including admissibility conditions and their graphical representations, are discussed. [ABSTRACT FROM AUTHOR]

Abstract: Steam reforming of methanol over a Cu/ZnO/Al2O3 catalyst has been investigated over the temperature range of 493–573K at atmospheric pressure in a fixed bed reactor. A series of catalysts were prepared by wet impregnation and characterized by atomic absorption spectroscopy, surface area, pore volume, pore size and X-ray diffraction technique. The X-ray photoelectron spectroscopy and thermogravimetry analysis of deactivated catalyst was done to investigate the nature of coke deposited on catalyst surface. The rate of coke formation and its influence over catalyst deactivation have also been studied. A monolayer–multilayer mechanism is proposed to model the coke formation with time and to study its effect on methanol conversion. Deactivation model was coupled with the kinetic model available in the literature to study the effect of coke formation on activity. The parameters of deactivation model for the Cu/ZnO/Al2O3 (10/5/85wt.%) catalyst have been determined by fitting the experimental data for methanol conversion and coke deposition. This model achieved the key objective of predicting the experimental observation with 95% accuracy. [Copyright &y& Elsevier]

Porous silicon is an efficient photo- and electro-luminescent material and represents a promising candidate for opto-electronic applications. On the other hand, quasiperiodic structures have been shown to be effective media for light localization and third harmonic generation. In this work, we present a photonic model for quasiperiodic multilayer structures, which are built experimentally by alternating porous silicon layers with high and low refractive indices. The analysis of the light propagation through these structures is based on the transfer matrix theory. The theoretical reflectance spectrum is compared with experimental data, observing a good agreement. [Copyright &y& Elsevier]

The article studies x-ray, scanning electron microscopy and magnetic properties of amorphous Fe60Nb40 alloy. Amorphous alloys play an important role both from basic research and application point of view. Among various methods available for making the amorphous alloy, solid state amorphization is the most important and has become an alternative route to rapid solidification process. The study revealed that the magnetic properties are enhanced due to annealing during the measurement process. This annealing during the measurement enhances the formation of ferromagnetic clusters in the paramagnetic host.

Objective: To determine the effects of intramuscular morphine sulfate on the pharmacokinetics of moxifloxacin. Design: This was a single-centre, randomised, two-way, nonblinded crossover study in healthy young males and females. Participants: 20 healthy volunteers (15 males, five females) with a mean age of 34 years were enrolled and considered evaluable for the pharmacokinetic analysis. Methods: Moxifloxacin was given under two conditions separated by a minimum 7-day washout period: alone as a single oral 400mg dose, and immediately following 10mg of intramuscular morphine sulfate. Concentrations of moxifloxacin in serum were determined by a validated HPLC procedure with fluorescence detection. Outcome Measures and Results: Pharmacokinetic parameters estimated were maximum serum concentration (C), time to reach C (t), area under the concentration-time curve from zero to infinity (AUC), and terminal elimination half-life (t). The natural logarithms of AUC and C were compared by analysis of variance. The mean moxifloxacin serum concentration vs time profiles were similar between the two treatments. The geometric least square mean C values for moxifloxacin were 3.42 mg/L when given alone vs 2.85 mg/L with morphine, producing a ratio (moxifloxacin with morphine vs moxifloxacin alone) of 0.83, with a 90% confidence interval (CI) about the ratio of 0.71 to 0.98. The geometric mean AUC values for moxifloxacin alone and with morphine were 41.5 and 39.6 mg/L·h; the ratio of means was 0.96, with a 90% CI of 0.87 to 1.04. t and t values for moxifloxacin were unchanged when coadministered with morphine. The single oral dose of moxifloxacin 400mg was well tolerated when taken with and without morphine sulfate. Conclusions: Administration of a single intramuscular dose of morphine did not reduce the bioavailability or alter the elimination profile of oral moxifloxacin. These results suggest that concurrent administration of intramuscular morphine and oral moxifloxacin is unlikely to reduce the efficacy of the quinolone. [ABSTRACT FROM AUTHOR]

The increasing use of nanomaterials in consumer products is expected to lead to environmental contamination sometime soon. As water pollution is a pressing issue that threatens human survival and impedes the promotion of human health, the search for adsorbents for removing newly identified contaminants from water has become a topic of intensive research. The challenges in the recyclability of contaminated water continue to campaign the development of highly reusable catalysts. Although exfoliated 2D MXene sheets have demonstrated the capability towards water purification, a significant challenge for removing some toxic organic molecules remains a challenge due to a need for metal-based catalytic properties owing to their rapid response. In the present study, we demonstrate the formation of hybrid structure AuNPs@MXene (Mo2CT x ) during the sensitive detection of Au nanoparticle through MXene sheets without any surface modification, and subsequently its applications as an efficient catalyst for the degradation of 4-nitrophenol (4-NP), methyl orange (MO), and methylene blue (MB). The hybrid structure (AuNPs@MXene) reveals remarkable reusability for up to eight consecutive cycles, with minimal reduction in catalytic efficiency and comparable apparent reaction rate constant (K app) values for 4-NP, MB, and MO, compared to other catalysts reported in the literature. [ABSTRACT FROM AUTHOR]

Aim: To analyse the technical challenges, clinical success, and associated complications of endovascular and percutaneous embolisation of pancreatitis-related pseudoaneurysms.Materials and Methods: A retrospective study of patients referred for embolisation of pancreatitis-related pseudoaneurysms between January 2014 and March 2019 was conducted. Computed tomography angiography (CTA) was performed to assess the morphology of the aneurysms prior to any intervention. Percutaneous or endovascular embolisation was performed. Details of CTA and methods of embolisation were recorded. Technical success, clinical success, and complications were reported.Results: A total of 80 patients (mean age, 40.69 ± 13.41 years, 73 male) underwent embolisation during the study period. Pseudoaneurysms were related to chronic pancreatitis (CP) in 44 (55%) patients and acute pancreatitis (AP) in 36 (45%) patients. Pseudoaneurysms were detected in 65 (81.2%) patients on CTA. The most common site of pseudoaneurysms was gastroduodenal artery (GDA) followed by splenic artery. Seven patients were treated with percutaneous thrombin injection and five were treated with percutaneous glue injection under ultrasound/fluoroscopy guidance. The remaining patients (n=68) underwent catheter angiography with endovascular embolisation. Technical success was achieved in 4/7 (57%) percutaneous thrombin cases and in all the cases (5/5, 100%) with percutaneous glue or endovascular (68/68,100%) embolisation.Conclusion: Endovascular or percutaneous embolisation of pseudoaneurysms has high technical success with an excellent safety profile. [ABSTRACT FROM AUTHOR]

Layered optical devices with a lateral gradient can be fabricated through electrochemical synthesis of porous silicon (PS) using a position dependent etching current density j (r ∥). Predicting the local value of j (r ∥) and the corresponding porosity p (r ∥) and etching rate v (r ∥) is desirable for their systematic design. We develop a simple analytical model for the calculation of j (r ∥) within a prism shaped cell. Graded single layer PS samples were synthesized and their local calibration curves p vs j and v vs j were obtained from our model and their reflectance spectra. The agreement found between the calibration curves from different samples shows that from one sample we could obtain full calibration curves which may be used to predict, design, and fabricate more complex non-homogeneous multilayered devices with lateral gradients for manifold applications. Image 1 • A simple expression was found for computing the current density during the etching process of layered porous silicon systems with lateral gradients. • The expression is an exponentially fast converging series, each term of which is given by a simple analytical formula. • Full calibration curves for porosity and etching rate can be obtained from measurements on different positions along the surface of a single sample. • Useful for design and fabrication of multilayered PS GRIN devices with a lateral gradient of porosity and thicknesses.. [ABSTRACT FROM AUTHOR]

Background: Granzyme-B is a serine proteinase expressed and released mainly by the cytotoxic T and NK cell. Granules intact Granzyme-B is directly delivered into the target cell, while extracellular Granzyme-B, released in serum leads to nonspecific cleavages of extracellular matrix molecules like vitronectin, collagen, TGF-ß, IL-1 and invites systemic inflammation, tissue remodeling and fibrosis leading to the development of chronic renal allograft dysfunction. Objective: We aimed to immunophenotype the Granzyme-B positive T-lymphocyte subset and Granzyme-B role in the development of chronic renal allograft dysfunction. Methods: We have analyzed the Granzyme-B+CD8+T/CD8neg and Granzyme-B+CD3+/CD3neg cell subset by the flowcytometry and serum Granzyme-B level by the enzyme-linked immunosorbent assay. Results: We have found that the frequency of Granzyme-B+ CD8neg CD3+T cell, Granzyme-B+ CD8lowCD3+T cell and Granzyme-B+ CD8high CD3+T cell subset was significantly lower and serum Granzyme-B level was significantly higher in CAD group. The frequency of CD3+T, CD3neg lymphocyte, CD8neg CD3+T, CD8lowCD3+T, CD8high CD3+T, Granzyme-B+CD3negCD8neg lymphocyte was similar between the group. The frequency of CD3+CD8negGzm-B+ cell was negatively correlated with serum creatinine and CD3+CD8highGzm-B+ cell was negatively correlated with serum Granzyme-B level. Similarly, Serum Granzyme-B level was positively correlated with serum creatinine, urine proteinuria and negatively with eGFR. Conclusion: The circulating frequency of Granzyme-B+ CD8neg CD3+T cell, Granzyme-B+ CD8lowCD3+T cell and Granzyme-B+ CD8high CD3+T cell subsets were significantly lower and serum Granzyme-B level was significantly higher in renal allograft recipients with CAD. [ABSTRACT FROM AUTHOR]

In the present work, regularity of the pores generated during the electrochemical etching of silicon wafer is analyzed. The wafer-electrolyte (ethanolic hydrofluoric acid) composite is placed in an electrochemical cell operated galvanostatically at a fixed (set-point) anodic current. This set-point current is subsequently perturbed by a sub-threshold periodic current signal. Numerous experiments were performed for diverse experimental configurations. Some of the experimental parameters varied were hydrofluoric concentration, set-points, and the properties of the input periodic signal (i.e., duty cycle and amplitude). The regularity of the generated pore size distribution was quantified by calculating the spatial normalized variance (NV). For certain experimental configurations, as described later, the phenomena of Periodic Stochastic Resonance (PSR) could be provoked. In PSR, enhanced regularity of the Porous Silicon nanostructures for an optimal HF concentration is observed. Consequently, the spatial NV versus the HF concentration curve exhibits a unimodal profile. [ABSTRACT FROM AUTHOR]

• Identification and localization of defect in piezo-ceramic is performed using spatio-temporal wave imaging. • Ultrasonic wave imaging is performed using dual point contact excitation and detection technique. • A spectral decomposition algorithm is developed to suppress the transmitted wave component and retain reflected waves. • Algorithm retains and exemplifies only the reflected wave scattering from surface defects. A novel experimental technique based on point contact and Coulomb coupling is devised and optimized for ultrasonic imaging of bulk and guided waves propagation in piezo-ceramics. The Coulomb coupling technique exploits the coupling and transfer of electric field to mechanical vibrations by excitation of phonons. The point contact excitation and detection technique facilitates the spatial-temporal imaging of ultrasonic waves. The motivation of this research is the diagnosis and localization of surface cracks in the piezoelectric sensors and actuators. The underlying principle of the detection scheme is that any discontinuity on the surface causes high localization of electric gradient. The localized electric field at the defect boundaries enables then to behave as secondary passive ultrasonic sources resulting in strong back reflections. However, due to the interference between transmitted and reflected wave components from rigid boundaries and defect, the resolution on the localization of the damage is challenging. Therefore, an algorithm based on the two-dimensional spectral decomposition is utilized for selective suppression of the transmitted wave. The algorithm includes data transformation and vectorization in polar coordinates for efficient spectral decomposition. In the spectral domain, the complex wave component (phase and amplitude) are suppressed for the transmitted wave field. The reflected wave component in the spectral domain is retained and retrieved back using inverse spectral transformation. The algorithm is successful in retaining and exemplifying only the reflected wave sources arising from the strong scattering of ultrasonic waves from the surface and sub-surface defects. In summary, a novel experimental technique based on Coulomb coupling and spectral decomposition technique has been implemented for localization of surface defect in piezo-ceramic structures. [ABSTRACT FROM AUTHOR]

Interaction of noise with nonlinear electrochemical kinetics involving the etching of porous silicon is studied experimentally. It is realized that by monotonically increasing the level of internal noise, one can tune the regularity of the spatial distribution of pores in silicon nanostructures. This regularity of the noise provoked structures is quantified using a spatial normalized variance technique in conjunction with the calculation of Hurst exponents. Our experimental results indicate the emergence of intrinsic coherence resonance. Consequently, there exists an optimal value of internal noise for which the spatial distribution of nanopores attain maximal regularity. This regularity of the pores can be useful for enhancing the optical response of porous silicon based devices. [ABSTRACT FROM AUTHOR]

In the present work, solvent extraction of Dy(III) from chloride solutions using 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (PC88A) and Cyanex 572 (a mixture of phosphonic and phosphinic acid extractants) diluted in kerosene has been reported. Pourbaix and speciation diagrams were plotted to understand the chemistry and formation of different species of Dy(III) in chloride solutions. The effects of different extraction parameters such as pH (1–5), extractant concentration (1–60 mM) and chloride concentration (0.05–1 M) were investigated. PC88A was found to extract Dy(III) ions better than Cyanex 572 under similar conditions. Experimental results showed that Dy(III) extraction reaction occurred via a cation exchange mechanism, which was further supported by Fourier-transform infrared spectroscopy (FTIR) studies of organic solutions loaded with Dy(III). Separation studies of Dy(III) from a mixed solution of 16 rare earth elements (REEs) indicate that PC88A works better for light REEs/Dy separation while selectivity of middle and heavy REEs over Dy(III) are superior with Cyanex 572. Molecular modeling was employed to calculate the Gibbs energies of Dy ions in aqueous and organic phases (consisting of phosphonic acid in heptane), which supported the experimental results. • Solvent extraction of Dy(III) from chloride solutions was studied. • PC88A extracts Dy ions more effectively than Cyanex 572. • PC88A outperformed Cyanex 572 in separating Dy ions from light REEs. • Standard Gibbs energies of Dy were calculated using molecular modeling. [ABSTRACT FROM AUTHOR]