291 research outputs found
Ultra-Stable and Robust Response to X-Rays in 2D Layered Perovskite Micro-Crystalline Films Directly Deposited on Flexible Substrate
2D layered hybrid perovskites have recently attracted an increasing interest as active layers in LEDs and UV–Vis photodetectors. 2D perovskites crystallize in a natural self-assembled quantum well-like structure and possess several interesting features among which low-temperature (<100 °C) synthesis and low defect density. Here are presented solid-state ionizing radiation direct detectors based on the 2D layered hybrid perovskite PEA2PbBr4 (PEA = C6H5C2H4NH3+) deposited from solution using scalable techniques and directly integrated onto a pre-patterned flexible substrate in the form of micro-crystalline films displaying crystal-like behavior, as evidenced by the ultra-fast (sub-microsecond) and good detection performances under UV light. The effective detection of X-rays (up to 150 kVp) is demonstrated with sensitivity values up to 806 µC Gy−1 cm−2 and Limit of Detection of 42 nGy s−1, thus combining the excellent performance for two relevant figures of merit for solid-state detectors. Additionally, the tested devices exhibit exceptionally stable response under constant irradiation and bias, assessing the material robustness and the intimate electrical contact with the electrodes. PEA2PbBr4 micro-crystalline films directly grown on flexible pre-patterned substrate open the way for large-area solid-state detectors working at low radiation flux for ultra-fast X-ray imaging and dosimetry
Oral Candidiasis amongst cancer patients at Qods Hospital
Background: Within the past two decades, Candida species have emerged as major human pathogens and are currently the fourth most common cause of nosocomial infection. Propose of this study was to determine the occurrence of oral Candidiasis among cancer patients at Qods hospitals in Sanandaj.Materials and Methods: Sixty cancer patients were examined for oral candidiasis. For all patients, the clinical diagnosis had to be confirmed microbiologically by the presence of yeasts and / or hyphae or pseudohyphae on potassium hydroxide–treated smears of oral swabs. Oral samples were obtained and cultured on Sabouraud's dextrose agar and CHROMagar.Results: 25 out of the 60 patients (41.7%) were males and 35 (58.3%) were females ranging in age from 15 to 79 years. Gastrointestinal cancer and Breast cancer were the most frequent cancer in the studied group, accounting for 65 % and 18.4 % respectively. The mean weight of the patients was 52.67 Kg (range, 38– 80 Kg). Similarly, the mean of hospital stay was 3.58 days (range; 1-9 days). From these patients, 19 Candida spp were isolated; C. albicans alone outnumbered other species and accounted for 73.68% episodes of trash. For C. albicans isolates, the MIC values ranges from 1 to 9 Z g / ml μg / ml for polyenes and from 0.03 to 16 Z g / ml for the azole antifungals. All the Candida albicans had closely related MFCs values.Conclusion: In conclusions, the finding of our study strongly suggest that oral candidiasis is a frequent complication among cancer patients, being C. albicans the main etiological agent.Keywords: Cancer, Oral candidiasis, Candida albicans, Antifungal agentsdoi: 10.4314/ajcem.v12i3.
Sensor Coordination for Behavior of Search Robot Using Simultaneous Localization and Mapping (SLAM)
We developed a robot for searching victims for survivors of natural disasters. Almost all robots need to navigate a state in the environment to help people around them, therefore the robot should have performance a mapping system. Thus improve the performance of robots in knowing the obstacles, the position and the direction toward the robot with the task of each sensor is to detect obstacles or objects that exist in the use of ultrasonic sensors to avoid bumping into obstacles, to detect the position and determine the distance of the robot using a rotary sensor encoder and to determine the direction toward, direction and elevation angle of the robot using IMU sensor. Whole of the sensor is set by the microcontroller STM32F407VGT6 that sent data from each sensor to a PC using XBee Pro. Therefore, robot create a mapping with OpenGL on the PC. Mapping system plays an important role for fast and accurate to the destination. We conclude, in the robot SLAM method depends on the precision of the data in the sensor US2 (Right), US4 (Left) and the rotary encoder. The test results of the output data at the right ultrasonic sensor produces error US2 16.9%, 14.6% US4 left ultrasonic and rotary encoder sensor error to 19.45%
Designing Ultraflexible Perovskite X-Ray Detectors through Interface Engineering
X-ray detectors play a pivotal role in development and advancement of humankind, from far-reaching impact in medicine to furthering the ability to observe distant objects in outer space. While other electronics show the ability to adapt to flexible and lightweight formats, state-of-the-art X-ray detectors rely on materials requiring bulky and fragile configurations, severely limiting their applications. Lead halide perovskites is one of the most rapidly advancing novel materials with success in the field of semiconductor devices. Here, an ultraflexible, lightweight, and highly conformable passively operated thin film perovskite X-ray detector with a sensitivity as high as 9.3 ± 0.5 µC Gy−1 cm−2 at 0 V and a remarkably low limit of detection of 0.58 ± 0.05 μGy s−1 is presented. Various electron and hole transporting layers accessing their individual impact on the detector performance are evaluated. Moreover, it is shown that this ultrathin form-factor allows for fabrication of devices detecting X-rays equivalently from front and back side
Network Metrics Detection to Support Internet of Things Application Orchestration
Software DefinedWireless Sensor Networks (SDWSN) play an important role to serve as an infrastructure to Internet of Things (IoT) applications. In order to improve coverage, reduce costs, and make better use of the available resources, sharing the infrastructure among multiple applications is necessary. Works in the literature aim to enable resource sharing by allocating applications dynamically according to the resources available on the node. However, these works do not monitor if a node stops complying with application requirements once the application is allocated. Thus, network metrics detection is essential to identify nodes that are not able to comply with the application requirements. In this paper, we present the IT-SDN Manager architecture which is composed of a monitoring module and a resource orchestrator. The monitoring module monitors the network metrics, enabling the orchestrator to identify nodes that reach a certain threshold for energy available and packet loss. This threshold configuration depends on the metric characteristics. For packet loss, we present a study showing how it should be defined according to the network size and applications executed in the network. In order to evaluate the orchestrator detection rate, we set two application requirements to identify nodes that reach 90% of available energy and packet loss greater than the obtained threshold for each scenario studied. Results from the simulations executed show that the resource orchestrator detects all the nodes that reach the available energy threshold, and at least 85%, with an average of 97%, of the nodes that reach the packet loss threshold
Implementing the Five-A Model of technical refinement: Key roles of the sport psychologist
There is increasing evidence for the significant contribution provided by sport psychologists within applied coaching environments. However, this rarely considers their skills/knowledge being applied when refining athletes’ already learned and well-established motor skills. Therefore, this paper focuses on how a sport psychologist might assist a coach and athlete to implement long-term permanent and pressure proof refinements. It highlights key contributions at each stage of the Five-A Model—designed to deliver these important outcomes—providing both psychomotor and psychosocial input to the support delivery. By employing these recommendations, sport psychologists can make multiple positive contributions to completion of this challenging task
A Marketplace-based Approach to Cloud Network Slice Composition Across Multiple Domains
Cloud network slicing can be defined as the process that enables isolated end-to-end and on-demand networking abstractions, which: (a) contain both cloud and network resources, and (b) are independently controlled, managed and orchestrated. This paper contributes to the vision of the NECOS project and relevant platform, that aim to address the limitations of current cloud computing infrastructures to accomplish the challenging requirements of the slicing approach. The NECOS platform implements the Slice-as-a-Service model, enabling the dynamic creation of end-to-end (E2E) slices from a set of constituent slice parts contributed from multiple domains. A challenging issue is to define the facility that implements dynamic slice resource discovery, aligned to the requirements of the slice owner or tenant, over different infrastructure providers. Here, we propose a Marketplace-based approach implementing relevant federated interactions for the resource discovery and we detail its architecture, workflows, and information model. We also present its initial implementation details and provide both quantitative and qualitative experimental results validating its main operation
First national intercomparison of solar ultraviolet radiometers in Italy
A blind intercomparison of ground-based ultraviolet (UV) instruments has been organized for the first time in Italy. The campaign was coordinated by the Environmental Protection Agency of Aosta Valley (ARPA Valle d'Aosta) and took place in Saint-Christophe (45.8 degrees N, 7.4 degrees E, 570 m a.s.l.), in the Alpine region, from 8 to 23 June 2010. It involved 8 institutions, 10 broadband radiometers, 2 filter radiometers and 2 spectroradiometers. Synchronized measurements of downward global solar UV irradiance at the ground were collected and the raw series were then individually processed by the respective operators on the base of their own procedures and calibration data. A radiative transfer model was successfully applied as an interpretative tool. The input parameters and output results are described in detail. The comparison was performed in terms of global solar UV Index and integrated UV-A irradiance against a well-calibrated double monochromator spectroradiometer as reference. An improved algorithm for comparing broadband data and spectra has been developed and is discussed in detail. For some instruments, we found average deviations ranging from -16% up to 20% relative to the reference and diurnal variations as large as 15% even in clear days. Remarkable deviations were found for the instruments calibrated in the manufacturers' facilities and never involved in field intercomparison. Finally, some recommendations to the UV operators based on the campaign results are proposed
Moyal star product approach to the Bohr-Sommerfeld approximation
The Bohr-Sommerfeld approximation to the eigenvalues of a one-dimensional
quantum Hamiltonian is derived through order (i.e., including the
first correction term beyond the usual result) by means of the Moyal star
product. The Hamiltonian need only have a Weyl transform (or symbol) that is a
power series in , starting with , with a generic fixed point in
phase space. The Hamiltonian is not restricted to the kinetic-plus-potential
form. The method involves transforming the Hamiltonian to a normal form, in
which it becomes a function of the harmonic oscillator Hamiltonian.
Diagrammatic and other techniques with potential applications to other normal
form problems are presented for manipulating higher order terms in the Moyal
series.Comment: 27 pages, no figure
Structure of mixed ombrophyllous forests with Araucaria angustifolia (Araucariaceae) under external stress in Southern Brazil.
This study is part of the Floristic and Forest Inventory of Santa Catarina, conceived to evaluate forest resources, species composition and structure of forest remnants, providing information to update forest conservation and land use policy in Southern Brazilian State of Santa Catarina (95 000km²). In accordance to the Brazilian National Forest Inventory (IFN-BR), the inventory applies systematic sampling, with 440 clusters containing four crosswise 1 000m² plots (20x50m) each, located on a 10x10km grid overlaid to land use map based on classification of SPOT-4 images from 2005. Within the sample units, all woody individuals of the main stratum (DBH?10cm) are measured and collected (fertile and sterile), if not undoubtedly identified in field. Regeneration stratum (height>1.50m; DBH<10cm) is registered in 100m² in each sample unit. Floristic sampling includes collection of all fertile trees, shrubs and herbs within the sample unit and in its surroundings. This study performs analysis based on 92 clusters measured in 2008 within an area of 32 320km² of mixed ombrophyllous forests with Araucaria angustifolia located at the state’s high plateau (500m to 1 560m above sea level at 26º00’-28º30’ S and 49º13’-51º23’ W). Mean density (DBH?10cm) is 578 individuals/ha (ranging from 85/ha to 1 310/ha), mean species richness in measured remnants is 35 (8 to 62), Shannon and Wiener diversity index (H’) varies between 1.05 and 3.48. Despite high total species diversity (364 Magnoliophyta, five Coniferophyta and one tree fern) and relatively high mean basal area (25.75m²/ha, varying from 3.87 to 68.85m²/ ha), the overwhelming majority of forest fragments are considered highly impacted and impoverished, mostly by logging, burning and extensive cattle farming, turning necessary more efficient protection measures. Basal area was considered an appropriate indicator for stand quality and conservation status
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