131 research outputs found
Nanopores in Track-Etched Polymer Membranes as Substitutes for the Tight Junctions in a Novel Concept of an Artificial Corneal Endothelium
Hypofractionated radiation therapy for breast cancer: Preferences amongst radiation oncologists in Europe – Results from an international survey
Background and purpose: We aimed to assess the prescription preference about hypofractionated radiation therapy (HFRT) for breast cancer (BC) patients amongst radiation oncologists (ROs) practicing in Europe and to identify restraints on HFRT utilisation. Materials and methods: An online survey was circulated amongst ROs in Europe through personal, RO and BC societies’ networks, from October 2019 to March 2020. The statistical analyses included descriptive statistics, chi-squared testing, and logistic regression analysis. Results: We received 412 responses from 44 countries. HFRT was chosen as the preferred schedule for whole breast irradiation (WBI) by 54.7% and for WBI with regional nodes irradiation (RNI) by 28.7% of the responding ROs. In the case of postmastectomy RT with or without reconstruction, HFRT was preferred by 21.1% and 29.6%, respectively. Overall, 69.2% of the responding ROs selected at least one factor influencing the decision to utilise HFRT, the most frequent of which included age (51.4%), RNI (46.9%), internal mammary lymph nodes irradiation (39.7%), BC stage (33.5%) and implant-based breast reconstruction (31.6%). ROs working in academic centres (odds ratio, (OR), 1.7; 95% confidence interval, (CI); 1.1–2.6, p = 0.019), practicing in Western Europe (OR, 4.2; 95%CI; 2.7–6.6, p 50% of clinical time to BC patients (OR, 2.5; 95%CI; 1.5–4.2, p = 0.001) more likely preferred HFRT. Conclusion: Although HFRT is recognised as a new standard, its implementation in routine RT clinical practice across Europe varies for numerous reasons. Better dissemination of evidence-based recommendations is advised to improve the level of awareness about this clinical indication
Multiresidue determination of the penicillins regulated by the European Union in bovine, porcine and chicken muscle by LC-MS/MS
A multiresidue analysis method was developed to determine the content of penicillins in bovine, porcine and chicken muscle tissues. The procedure involves solid phase extraction (SPE) and subsequent analysis by liquid chromatography coupled with tandem mass spectrometry detection (LC-MS/MS) set by the European Union (EU) for all compounds. The method was validated according to EU guideline 2002/657/EC. The LOQ in tissues are below the maximum residue limits (MRLs) and appropriate quality parameters in terms of linearity, accuracy (recoveries higher than 70% for all antibiotics and animal tissues except for AMOX with 50% of recovery) and precision (in terms of intra and inter day with values lower than 12% in all cases) are obtained for the developed method. A study concerning to the matrix effect was made and it was concluded that similar matrix effect could be found in beef, pig and chicken. The method was applied to the analysis of samples of chicken from animals treated with amoxicillin
739 observed NEAs and new 2-4m survey statistics within the EURONEAR network
We report follow-up observations of 477 program Near-Earth Asteroids (NEAs)
using nine telescopes of the EURONEAR network having apertures between 0.3 and
4.2 m. Adding these NEAs to our previous results we now count 739 program NEAs
followed-up by the EURONEAR network since 2006. The targets were selected using
EURONEAR planning tools focusing on high priority objects. Analyzing the
resulting orbital improvements suggests astrometric follow-up is most important
days to weeks after discovery, with recovery at a new opposition also valuable.
Additionally we observed 40 survey fields spanning three nights covering 11 sq.
degrees near opposition, using the Wide Field Camera on the 2.5m Isaac Newton
Telescope (INT), resulting in 104 discovered main belt asteroids (MBAs) and
another 626 unknown one-night objects. These fields, plus program NEA fields
from the INT and from the wide field MOSAIC II camera on the Blanco 4m
telescope, generated around 12,000 observations of 2,000 minor planets (mostly
MBAs) observed in 34 square degrees. We identify Near Earth Object (NEO)
candidates among the unknown (single night) objects using three selection
criteria. Testing these criteria on the (known) program NEAs shows the best
selection methods are our epsilon-miu model which checks solar elongation and
sky motion and the MPC's NEO rating tool. Our new data show that on average 0.5
NEO candidates per square degree should be observable in a 2m-class survey (in
agreement with past results), while an average of 2.7 NEO candidates per square
degree should be observable in a 4m-class survey (although our Blanco
statistics were affected by clouds). At opposition just over 100 MBAs (1.6
unknown to every 1 known) per square degree are detectable to R=22 in a 2m
survey based on the INT data, while our two best ecliptic Blanco fields away
from opposition lead to 135 MBAs (2 unknown to every 1 known) to R=23.Comment: Published in Planetary and Space Sciences (Sep 2013
The cellular and synaptic architecture of the mechanosensory dorsal horn
The deep dorsal horn is a poorly characterized spinal cord region implicated in processing low-threshold mechanoreceptor (LTMR) information. We report an array of mouse genetic tools for defining neuronal components and functions of the dorsal horn LTMR-recipient zone (LTMR-RZ), a role for LTMR-RZ processing in tactile perception, and the basic logic of LTMR-RZ organization. We found an unexpectedly high degree of neuronal diversity in the LTMR-RZ: seven excitatory and four inhibitory subtypes of interneurons exhibiting unique morphological, physiological, and synaptic properties. Remarkably, LTMRs form synapses on between four and 11 LTMR-RZ interneuron subtypes, while each LTMR-RZ interneuron subtype samples inputs from at least one to three LTMR classes, as well as spinal cord interneurons and corticospinal neurons. Thus, the LTMR-RZ is a somatosensory processing region endowed with a neuronal complexity that rivals the retina and functions to pattern the activity of ascending touch pathways that underlie tactile perception
Ultrathin and lightweight organic solar cells with high flexibility
Application-specific requirements for future lighting, displays and photovoltaics will include large-area, low-weight and mechanical resilience for dual-purpose uses such as electronic skin, textiles and surface conforming foils. Here we demonstrate polymer-based photovoltaic devices on plastic foil substrates less than 2 μm thick, with equal power conversion efficiency to their glass-based counterparts. They can reversibly withstand extreme mechanical deformation and have unprecedented solar cell-specific weight. Instead of a single bend, we form a random network of folds within the device area. The processing methods are standard, so the same weight and flexibility should be achievable in light emitting diodes, capacitors and transistors to fully realize ultrathin organic electronics. These ultrathin organic solar cells are over ten times thinner, lighter and more flexible than any other solar cell of any technology to date
Asymmetric Excitatory Synaptic Dynamics Underlie Interaural Time Difference Processing in the Auditory System
In order to localize sounds in the environment, the auditory system detects and encodes differences in signals between each ear. The exquisite sensitivity of auditory brain stem neurons to the differences in rise time of the excitation signals from the two ears allows for neuronal encoding of microsecond interaural time differences
Stress-Induced Reinstatement of Drug Seeking: 20 Years of Progress
In human addicts, drug relapse and craving are often provoked by stress. Since 1995, this clinical scenario has been studied using a rat model of stress-induced reinstatement of drug seeking. Here, we first discuss the generality of stress-induced reinstatement to different drugs of abuse, different stressors, and different behavioral procedures. We also discuss neuropharmacological mechanisms, and brain areas and circuits controlling stress-induced reinstatement of drug seeking. We conclude by discussing results from translational human laboratory studies and clinical trials that were inspired by results from rat studies on stress-induced reinstatement. Our main conclusions are (1) The phenomenon of stress-induced reinstatement, first shown with an intermittent footshock stressor in rats trained to self-administer heroin, generalizes to other abused drugs, including cocaine, methamphetamine, nicotine, and alcohol, and is also observed in the conditioned place preference model in rats and mice. This phenomenon, however, is stressor specific and not all stressors induce reinstatement of drug seeking. (2) Neuropharmacological studies indicate the involvement of corticotropin-releasing factor (CRF), noradrenaline, dopamine, glutamate, kappa/dynorphin, and several other peptide and neurotransmitter systems in stress-induced reinstatement. Neuropharmacology and circuitry studies indicate the involvement of CRF and noradrenaline transmission in bed nucleus of stria terminalis and central amygdala, and dopamine, CRF, kappa/dynorphin, and glutamate transmission in other components of the mesocorticolimbic dopamine system (ventral tegmental area, medial prefrontal cortex, orbitofrontal cortex, and nucleus accumbens). (3) Translational human laboratory studies and a recent clinical trial study show the efficacy of alpha-2 adrenoceptor agonists in decreasing stress-induced drug craving and stress-induced initial heroin lapse
Photoacoustic characterization of transient defects in potassium dihydrogen phosphate crystals
A study of noncovalent complexes involving single-stranded DNA and polybasic compounds using nanospray mass spectrometry
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