Non-covalent functionalization of pristine few-layer graphene using triphenylene derivatives for conductive poly (vinyl alcohol) composites

In this paper, we demonstrate a facile technique to disperse pristine few-layer graphene (FLG) in water utilizing a triphenylene based stabilizer (C10) that non-covalently functionalizes the surface without micelle formation. The yield of FLG in the final dispersion (0.2 mg FLG/mg C10) is much higher than comparable surfactants and polymers stabilizers. This dispersion is reversible in response to pH changes unlike conventional stabilizers. The C10-stabilized FLG dispersion is also stable against heat and lyophilization. This non-covalent functionalization does not disrupt the pristine structure of the graphene sheets; instead, these coatings allow for stable, aggregation-resistant FLG dispersion, as characterized through TEM. To demonstrate the utility of such dispersions, we prepared pristine FLG-loaded poly (vinyl alcohol) (PVA) composites by a simple solution casting process. This is the first example of PVA composites based on pristine graphene. These composites have enhanced electrical properties at relatively low filler fraction (0.26 vol% FLG). Moreover, these composites exhibit improved mechanical properties established by tensile and hardness tests results; these data suggest anisotropic reinforcement caused by graphene alignment.     

Transpedicular stabilization in spinal and vertebral column injuries in thoracic and lumbar spine segments

The authors present their own experience in application of transpedicular internal stabilization of the thoracic and lumbar spine. Clinical analysis was carried out in a group of 12 patients after vertebral column and spinal trauma managed surgically in the Department of Neurosurgery in Poznań between 1.06.95 and 31.12.96. Age of patients ranged from 19 to 56 years (mean age 35.08 +/- 13.04 yrs.). The level of vertebral fracture was as follows: thoracic (2 cases), thoraco-lumbar (6 cases) and lumbar (4 cases). Three patients were completely paraplegic. All patients underwent posterior or posterolateral surgical approach. The fractured parts of bones, translocated into vertebral canal were removed and nervous structures were decompressed. Transpendicular stabilization was performed after the decompression. Improvement of neurological condition was observed in 8 patients.     

Effect of different extraction methods on the recovery of chlorogenic acids,caffeine and Maillard reaction products in coffee beans

Water and ethanolic extracts were obtained from green and roasted (3 different roast degrees) Arabica and Robusta coffee beans. Three types of water extracts were prepared from the examined, finely ground material through: (a) brewing with boiling water, (b) boiling in water, and (c) boiling in water under elevated pressure. All these extracts were lyophilized. Two types of ethanolic extracts were derived from the examined material through (a) extraction of the finely ground coffee beans and (b) extraction of the solid residue that remained after boiling the coffee beans in water under elevated pressure. These ethanolic extracts were dried. Both water and ethanolic extracts were analyzed for concentration of potential antioxidants such as chlorogenic acids and caffeine (by HPLC) and Maillard reaction products (measurements of absorbance at 420 nm). Concentration of chlorogenic acids in Robusta extracts varied between 0.4 and 36.0 g × 100 g⁻¹ dry extract weight (db.), while in Arabica extracts it ranged from 0.1 to 22.4 g × 100 g⁻¹ db. Extracts of dark roasted Arabica contained more chlorogenic acids than those of Robusta. Concentration of caffeine, which in green and roasted coffee beans is maintained at the similar level, tended to increase in Robusta extracts with the roast degree and temperature of extraction with water, while in case of Arabica extracts there was no noticeable tendency. Caffeine concentrations varied between 0.12 and 8.41 g × 100 g⁻¹ db. and between 0.03 and 6.53 g × 100 g⁻¹ db. in Robusta and Arabica extracts, respectively. Ethanolic extracts were characterized by relatively higher caffeine concentrations and lower contents of brown pigments and chlorogenic acids as compared to water extracts. The richest in antioxidants were extracts of green Robusta coffee beans derived through boiling in water under elevated pressure.     

Exploring e-Science: An Introduction

A number of terms are in vogue that describe the transformation of science through utilization of Grid computing, Internet-based instrumentation, and global collaboration. For the purposes of this special theme section of the Journal of Computer-Mediated Communication, the term e-science serves as an umbrella for these initiatives. This article introduces the contributions to the collection and includes a number of suggestions for extending the exploratory work performed to date, including attention to disciplinary and contextual diversity and the importance of longitudinal research designs and historical awareness and of the social shaping of technology as a theoretical concept to understanding the changes currently underway in the scientific enterprise.     

Disruption of the middle bronchus

Disruption of the middle lobe broncus as a result of blunt chest trauma is described. Patient underwent emergency reconstructive operation. Follow-up examination revealed normal postoperative chest radiogram but bronchoscopy showed decreased patency of bronchial anastomosis. Perfusion lung scintigraphy showed severely decreased perfusion of the entire right lung. Concomitant fracture of right clavicle resulted in false joint which required surgical intervention 4 weeks after the chest trauma.     

The IAEA accident management programme

Accident prevention and mitigation programmes and the Emergency Response System (ERS) are important elements of the Agency's activities in the area of nuclear power plant (NPP) safety. Safety Codes and Guides on siting, design, quality assurance and the operation of NPPs have been produced and are used by NPP operating organizations. Nuclear safety evaluation services are provided by the IAEA. The Emergency Response System and the International Nuclear Event Scale (INES) have been developed. The framework for the development of an accident management programme has been set up. The main goal is to develop an Accident Management Manual to provide a systematic, structured approach to the development and implementation of an accident management programme at NPPs. An outline of the Manual has been distributed and the first draft is available. The component parts are: co-ordinated research programmes (CRPs) on severe accident management and containment behaviour; the use of vulnerability analysis; mitigation of the effects of hydrogen, and generic symptom oriented emergency operating procedures. The IAEA provides guidance by the dissemination of information on methods for accident management; collates information on approaches in this field in different organizations and countries; and arranges exchange of experience and the promulgation of knowledge through the training of NPP managers and senior technical staff.     

Extremity and eye lens doses in interventional radiology and cardiology procedures: first results of the ORAMED project

The main objective of WP1 of the ORAMED (Optimization of RAdiation protection for MEDical staff) project is to obtain a set of standardised data on extremity and eye lens doses for staff in interventional radiology (IR) and cardiology (IC) and to optimise staff protection. A coordinated measurement program in different hospitals in Europe will help towards this direction. This study aims at analysing the first results of the measurement campaign performed in IR and IC procedures in 34 European hospitals. The highest doses were found for pacemakers, renal angioplasties and embolisations. Left finger and wrist seem to receive the highest extremity doses, while the highest eye lens doses are measured during embolisations. Finally, it was concluded that it is difficult to find a general correlation between kerma area product and extremity or eye lens doses.     

A pilot study of a cognitive restructuring program for treating posttraumatic disorders in adolescents.

The study explored the feasibility and efficacy of a manualized cognitive restructuring program for treating adolescents suffering from posttraumatic stress disorder (PTSD). Nine girls and 3 boys (mean age 16 years; range = 14–18), with PTSD, were recruited from a community mental health center and a tertiary health care center and enrolled in a pilot study. The adolescents were seen weekly for 12–16 weeks of individual treatment. Variables assessed included: trauma history, PTSD diagnosis and severity, depression, substance abuse, and client satisfaction. Twelve adolescents consented to treatment; 9 completed the program. The number of types of traumas reported averaged 6.5 (range = 1–13). Paired t tests were used to test prepost change for PTSD symptoms and depression, in completers. From baseline to posttreatment, there were statistically significant improvements in PTSD and depression. Treatment gains were maintained at 3 month follow-up. Preliminary results suggest the feasibility of implementing a manualized cognitive restructuring program to treat PTSD in adolescents. Completers rated themselves as improved and satisfied at posttreatment and 3-month follow-up. Feedback from referring clinicians also indicated high satisfaction. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Genotypic difference in postharvest characteristics of hardy kiwifruit (Actinidia arguta and its hybrids), as a new commercial crop: Part II. Consumer acceptability and its main drivers

Actinidia arguta, called also hardy kiwifruit, is an exotic fruit of Actinidia genus which have obtained commercial interest in recent years. Its high frost hardiness, relatively short vegetation period and pro-healthy properties make it very interesting, especially in cold regions. The aim of the presented study was to identify main drivers of postharvest consumer acceptability of A. arguta (and its hybrids with A. purpurea) fruit among its sensory (flavour and texture) attributes and appearance characteristics (size and colour). To achieve that goal nine genotypes were assessed by over 200 consumers during two-year experiment. In order to perform a possibly broad research the chosen genotypes included five of the popular A. arguta cultivars grown around the world, two promising genotypes selected at Warsaw University of Life Sciences (WULS) as well as two hybrids (A. arguta × A. purpurea) from the same source. The study consisted of the consumer assessment of external (appearance) and internal (flavour and texture) fruit liking. The results showed general positive consumer acceptance of hardy kiwifruit with low differentiation of its genotypes. No segment of consumers disliking fruit appearance was found and segments disliking their taste and flavour constituted only about 14% in 2005 and 6% of consumers in 2006, respectively. Study indicated a significant effect of fruit size on consumers as it was highly correlated with the mean liking scores in each of consumer segments. The pink-red skin colour has also large positive impact on consumer's Actinidia choice observed in outstanding acceptance of small ‘D11’ genotype. The most preferable fruit should moreover have sweet taste and odour as these features are significant for most of consumers. Genotypes best meeting consumer preferences were pointed, including A. arguta × A. purpurea, which should obtain special breeders' focus.