Direct-written polymer field-effect transistors operating at 20 MHz

Printed polymer electronics has held for long the promise of revolutionizing technology by delivering distributed, flexible, lightweight and cost-effective applications for wearables, healthcare, diagnostic, automation and portable devices. While impressive progresses have been registered in terms of organic semiconductors mobility, field-effect transistors (FETs), the basic building block of any circuit, are still showing limited speed of operation, thus limiting their real applicability. So far, attempts with organic FETs to achieve the tens of MHz regime, a threshold for many applications comprising the driving of high resolution displays, have relied on the adoption of sophisticated lithographic techniques and/or complex architectures, undermining the whole concept. In this work we demonstrate polymer FETs which can operate up to 20 MHz and are fabricated by means only of scalable printing techniques and direct-writing methods with a completely mask-less procedure. This is achieved by combining a fs-laser process for the sintering of high resolution metal electrodes, thus easily achieving micron-scale channels with reduced parasitism down to 0.19 pF mm(-1), and a large area coating technique of a high mobility polymer semiconductor, according to a simple and scalable process flow

Stress in nursing staff: a comparative analysis between intensive care units and general medicine units

It's a current belief that stress is an outstanding feature of intensive care units, in particular within nursing staff. The aim of this study was to compare some variables belonging to stress (i.e. anxiety, depression and `Burnout' syndrome) between nurses working in intensive care units (ICUs) and general medicine units (GMUs). Materials and methods We studied a population of 883 nurses working in ICUs, distributed in 79 Italian hospitals (70.1 % female) and 509 nurses working in GMUs, distributed in 35 Italian hospitals (80.2 % female). We asked them to fill in a form including: 1) general data and his/her work environment; 2) different evaluation standardized scales - the Hospital Anxiety and Depression Scale, divided into anxiety (HAD A) and depression (HAD D) status 0-7 `non cases', 8-10 `doubtful cases', 11-21 `cases'; the S.T.A.I. scale, divided into acute anxiety (Y-1) and chronic anxiety (Y-2) status; the Maslach Burnout Inventory-Human Services Survey (MBI.) divided into Emotional Exhaustion (EE), 64 18 `low', 19-26 `average', 65 27 `high', Depersonalization (DP) and Personal Accomplishment (PA). We also evaluated the different reasons of anxiety through individual questions (higher value, more anxiety): A1, a critically ill patient; A2, a young patient; A3, an old patient; A4, a suicidal patient; A5, a terminal patient; A6, presence of mechanical supports; A7, relationship with patients' relatives. The comparison between the two groups was performed by the Mann-Whitney Rank Sum test and z-test; statistical significance was accepted as P<0.05. Results The results, expressed as median value, with 25th and 75th percentile in brackets, are shown in Tables 1 and 2. Table 1 also shows the proportions of nurses that had a highest value of HAD A and M.B.I. EE. Conclusions Pathologic anxiety and emotional exhaustion are more prevalent in nurses working in GMUs. Thus, contrary to a common belief, `stress' is a more distinctive peculiarity of general medicine units than intensive care units