Brain mechanisms for reading and language processing in spina bifida meningomyelocele: A combined magnetic source- and structural magnetic resonance imaging study.

Objective: The development of the ability to process spoken and written language depends upon a network of left hemisphere temporal, parietal, and frontal regions. The present study explored features of brain organization in children with spina bifida meningomyelocele (SBM) and shunted hydrocephalus, who commonly present with precocious development of word reading skills and preservation of vocabulary and grammar skills. Method: Eight children with SBM were compared with 15 IQ and reading-level matched, typically developing controls on MRI-based morphometric and Magnetic Source Imaging-derived neurophysiological profiles. Results: Children with SBM showed reduced magnetic activity in left inferior parietal regions during spoken word recognition and pseudoword reading tasks. We also noted reduced surface area/volume in inferior parietal and posterior temporal regions in SBM and increased gray matter volumes in left middle frontal regions and gyral complexity in left posterior temporal and inferior parietal regions. Conclusions: A complex pattern of changes in cortical morphology and activation may serve as evidence for structural and functional brain reorganization ensuring preservation of language and decoding abilities in children with SBM. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Preparation of granular activated carbon from oil palm shell by microwave-induced chemical activation: Optimisation using surface response methodology

In this study, waste palm shell was used to produce activated carbon (AC) using microwave radiation and zinc chloride as a chemical agent. The operating parameters of the preparation process were optimised by a combination of response surface methodology (RSM) and central composite design (CCD). The influence of the four major parameters, namely, microwave power, activation time, chemical impregnation ratio and particle size, on methylene blue (MB) adsorption capacity and AC yield were investigated. Based on the analysis of variance, microwave power and microwave radiation time were identified as the most influential factors for AC yield and MB adsorption capacity, respectively. The optimum preparation conditions are a microwave power of 1200 W, an activation time of 15 min, a ZnCl₂ impregnation ratio of 1.65 (g Zn/g precursor) and a particle size of 2 mm. The prepared AC under the optimised condition had a BET surface area (S_BET) of 1253.5 m²/g with a total pore volume (V_tot) of 0.83 cm³/g, which 56% of it was contributed to the micropore volume (V_mic).     

Polyphenol-Induced Adhesive Liquid Metal Inks for Substrate-Independent Direct Pen Writing

Surface patterning of liquid metals (LMs) is a key processing step for LM-based functional systems. Current patterning methods are substrate specific and largely suffer from undesired imperfections—restricting their widespread applications. Inspired by the universal catechol adhesion chemistry observed in nature, LM inks stabilized by the assembly of a naturally abundant polyphenol, tannic acid, has been developed. The intrinsic adhesive properties of tannic acid containing multiple catechol/gallol groups, allow the inks to be applied to a variety of substrates ranging from flexible to rigid, metallic to plastics and flat to curved, even using a ballpoint pen. This method can be further extended from hand-written texts to complex conductive patterns using an automated setup. In addition, capacitive touch and hazardous heavy metal ion sensors have been patterned, leveraging from the synergistic combination of polyphenols and LMs. Overall, this strategy provides a unique platform to manipulate LMs from hand-written pattern to complex designs onto the substrate of choice, that has remained challenging to achieve otherwise.     

Behaviors of capacitive and Pirani vacuum gauges

Knowing the exact pressure of the process has a great impact on the validity of the results, product quality, energy efficiency, and in some processes, on the security of work with the system. Hence, the calibration of the barometers and the accuracy of the readings should be taken seriously. Choosing the appropriate time interval for re-calibration is done according to the extent and conditions of use, uncertainty, and the inaccuracy allowed in measurement, constructive suggestion, and some other things. Failure to pay attention to the importance of periodic calibration in vacuum gauges leads to some irreparable losses in the research project and the vacuum generator system. In this study, using McLeod's barometer, the deviation of capacitive and Pirani vacuum gauges is investigated at different time intervals in the middle vacuum range, and it is determined that the vacuum gauge faces a serious deviation from the actual calibrated amount for upper and lower ranges of middle vacuum in the same working pressure range over time.     

Pressure‐driven displacement flows of yield stress fluids: Viscosity ratio effects

We numerically investigate pressure‐driven, density‐unstable displacement flows of two miscible fluids along a near‐horizontal 2D channel. The displacing fluid is a Newtonian fluid, slightly heavier than the displaced yield stress (Bingham) fluid. The imposed displacement flow is laminar. We show that the displacement flow is mainly governed by five dimensionless numbers, and their combinations, including the Reynolds number (Re), the Bingham number (Bn), the densimetric Froude number (Fr), the viscosity ratio (m), and the channel inclination angle (β). In this work, we primarily focus on the viscosity ratio and provide a detailed understanding of the flow behaviours via studying the effects of m on displacement flow patterns, regime classifications based on slump‐type and centre‐type displacement flow regimes, leading and trailing displacement front features, and finally the effects of m at different inclination angles.     

Analyzing the fractal feature of nickel thin films surfaces modified by low energy nitrogen ion

Fractal concepts are used to explore how different energies (10, 20 and 50 keV) and fluence of 5 × 10¹⁷ N⁺ cm^?2 affect the morphology of nickel thin film. The nickel thin film with thickness of 100 nm is prepared by electron beam evaporation technique at room temperature on stainless steel (AISI 316) substrates. The nanoscale three‐dimensional (3‐D) surface micro‐morphologies are investigated by atomic force microscopy (AFM). Interface width is used to describe the surface height fluctuations. The autocorrelation function with height‐height correlation function give the quantitative data about the morphology of surface. The value of roughness exponent and fractal dimension is computed by height‐height correlation function. Fractal measure is an important analysis which provides fundamental insights into the texture characteristics and a direct way of testing their functional role.     

Bagged ensemble of Fuzzy C-Means classifiers for nuclear transient identification

This paper presents an ensemble-based scheme for nuclear transient identification. The approach adopted to construct the ensemble of classifiers is bagging; the novelty consists in using supervised fuzzy C-means (FCM) classifiers as base classifiers of the ensemble. The performance of the proposed classification scheme has been verified by comparison with a single supervised, evolutionary-optimized FCM classifier with respect of the task of classifying artificial datasets. The results obtained indicate that in the cases of datasets of large or very small sizes and/or complex decision boundaries, the bagging ensembles can improve classification accuracy. Then, the approach has been applied to the identification of simulated transients in the feedwater system of a boiling water reactor (BWR).     

Growth kinetics of bismuth nickel intermetallics

Bismuth (Bi)-based systems are of great interest as it is considered to potentially replace high lead (Pb)-content solders used in high temperature electronics. In particular, molten Bi strongly reacts with Ni to form higher melting point intermetallic compounds (IMCs) via transient liquid phase (TLP), which can offer a joining method alternative to the traditional solder approach. A fundamental understanding of nucleation and growth of intermetallic phases is crucial to create a reliable joint. Two intermetallic phases form between Bi and Ni (Bi₃Ni, BiNi). In this study, growth kinetics for Bi₃Ni and BiNi was investigated, both of which show a parabolic growth behavior. Bi₃Ni exhibits rapid growth and apparent activation energy of 65.5 kJ/mol at lower temperatures (from 160 to 240 °C) and of 132.9 kJ/mol at higher temperatures (>?240 °C), where the transition is likely due to a viscous-flow nature near melting temperature of Bi. On the other hand, BiNi grows at a later stage with a slower rate with the apparent activation energy of 125.6 kJ/mol (from 260 to 340 °C). In addition, based on the formation sequence and growth direction of these IMCs, interdiffusion coefficients for each of these IMCs were determined. Micro-hardness tests show that Bi₃Ni is softer and more brittle than BiNi.     

Synthesis and characterization of poly(4-vinylpyridine)/MCM-48 catalyst for one-pot synthesis of substituted 4H-chromenes

In this paper, we wish to report the synthesis and characterization of poly(4-vinylpyridine) supported on MCM-48 by in situ polymerization of 4-vinylpyridine in the presence of MCM-48. This catalyst was effectively employed as a novel heterogeneous basic catalyst for the one-pot synthesis of 4H-chromenes in aqueous medium. This catalyst was easily prepared, and showed considerable level of reusability.     

Is there an association between intradialytic hypotension and serum magnesium changes?

Intradialytic hypotension (IDH) is the most common complication of hemodialysis (HD). The aim of this study was to investigate the significance of intradialytic changes of serum magnesium (sMg) and its relation to IDH. We considered 58 patients undergoing HD. Serum magnesium was measured at start, after 2 hours, and at the end of the HD sessions. Total sMg concentration corrected for albumin was according to Krolles proposed formula. Blood pressure was measured every 30 min. Data were analyzed by SPSS.15. A P value of less than 0.05 was considered as significant. Occurrence of IDH among HD patients was 27.6% (16/58). Serum magnesium decreased significantly during HD session (P<0.05). Comparing corrected sMg in IDH group with non-IDH group showed that: corrected sMg was 0.66 ± 0.14 mmol/L vs. 0.84 ± 0.26 mmol/L at the start of dialysis (P=0.43), 0.62 ± 0.17 mmol/L vs. 0.74 ± 0.23 mmol/L (P=0.04) at 2 hours, and 0.61 ± 0.12 mmol/L vs. 0.72 ± 0.22 mmol/L (P=0.03) at the end of dialysis. Intradialytic hypotension episodes were significantly related to a decrease in sMg during dialysis (P=0.02). There was a significant decrease in sMg levels during dialysis. Intradialytic hypotension was significantly related to lowered sMg levels during dialysis.