6,346 research outputs found
Ku & C Band solid state switch matrix for satellite payloads using LTCC multilayer substrate
This paper describes the design and development of Ku and C band solid state switch matrix for multimedia satellite payloads. The design, through the use of advanced packaging techniques, allows significant savings on mass and volume with respect to traditional electromechanical switches while guaranteeing a comparable reliability
The COVID-19 Wellbeing Study: Examining perceived coercion and psychological wellbeing during the COVID-19 pandemic by means of an online survey, asynchronous virtual focus groups and individual interviews – a protocol
Introduction: The COVID-19 pandemic has resulted in
many countries applying restrictive measures, such as
lockdown, to contain and prevent further spread. The
psychological impact of lockdown and working as a
healthcare worker on the frontline has been chronicled
in studies pertaining to previous infectious disease
pandemics that have reported the presence of depressive
symptoms, anxiety, insomnia, and post-traumatic stress
symptoms. Potentially linked to psychological well-being
and not yet studied is the possibility that lockdown and
working on the frontline of the pandemic are associated
with perceptions of coercion.
Methods and analysis: The present study aimed
to examine perceived coercion in those who have
experienced COVID-19-related lockdown and/or worked
as a frontline healthcare worker across three European
countries. It aimed to describe how such perceptions may
impact on psychological well-being, coping and posttraumatic growth. It will employ an explanatory mixedmethods research methodology consisting of an online
survey and online asynchronous virtual focus groups
(AVFGs) and individual interviews. χ2
tests and analyses
of variance will be used to examine whether participants
from different countries differ according to demographic
factors, whether there are differences between cohorts on
perceived coercion, depression, anxiety and post-traumatic
growth scores. The relationship between coercion and
symptoms of distress will be assessed using multiple
regression. Both the AVFGs and the narrative interviews
will be analysed using thematic narrative analysis.
Ethics and dissemination: The study has been approved
by University College London’s Research Ethics Committee
under Project ID Number 7335/004. Results will be
disseminated by means of peer-reviewed publications and
at national and/or international conferences
Integrated geophysical and aerial sensing methods for archaeology: A case history in the Punic site of Villamar (Sardinia, Italy)
In this paper, the authors present a recent integrated survey carried out on an archaeological urban site, generally free of buildings, except some temporary structures related to excavated areas where multi-chamber tombs were found. The two methods used to investigate this site were thermal infrared and ground penetrating radar (GPR). The thermography was carried out with the sensor mounted under a helium balloon simultaneously with a photographic camera. In order to have a synthetic view of the surface thermal behavior, a simplified version of the existing night thermal gradient algorithm was applied. By this approach, we have a wide extension of thermal maps due to the balloon oscillation, because we are able to compute the maps despite collecting few acquisition samples. By the integration of GPR and the thermal imaging, we can evaluate the depth of the thermal influence of possible archaeological targets, such as buried Punic tombs or walls belonging to the succeeding medieval buildings, which have been subsequently destroyed. The thermal anomalies present correspondences to the radar time slices obtained from 30 to 50 cm. Furthermore, by superimposing historical aerial pictures on the GPR and thermal imaging data, we can identify these anomalies as the foundations of the destroyed building
Encapsulation of human articular chondrocytes into 3D hydrogel : phenotype and genotype characterization
This chapter is intended to provide a summary of the current materials used in cell encapsulation technology
as well as methods for evaluating the performance of cells encapsulated in a polymeric matrix. In
particular, it describes the experimental procedure to prepare a hydrogel matrix based on natural polymers
for encapsulating and culturing human articular chondrocytes with the interest in cartilage regeneration.
Protocols to evaluate the viability, proliferation, differentiation, and matrix production of
embedded cells are also described and include standard protocols such as the MTT and [3H] Thymidine
assays, reverse transcription polymerase chain reaction (RT-PCR) technique, histology, and immunohistochemistry
analysis. The assessment of cell distribution within the 3D hydrogel construct is also described
using APoTome analysis.(undefined
A Numerical Study of Ultrametricity in Finite Dimensional Spin Glasses
We use a constrained Monte Carlo technique to analyze ultrametric features of
a 4 dimensional Edwards-Anderson spin glass with quenched couplings J=\pm 1. We
find that in the large volume limit an ultrametric structure emerges quite
clearly in the overlap of typical equilibrium configurations.Comment: 8 one column pages, latex, 4 figures with epsfig.st
Voltage control of magnetocrystalline anisotropy in ferromagnetic - semiconductor/piezoelectric hybrid structures
We demonstrate dynamic voltage control of the magnetic anisotropy of a
(Ga,Mn)As device bonded to a piezoelectric transducer. The application of a
uniaxial strain leads to a large reorientation of the magnetic easy axis which
is detected by measuring longitudinal and transverse anisotropic
magnetoresistance coefficients. Calculations based on the mean-field
kinetic-exchange model of (Ga,Mn)As provide microscopic understanding of the
measured effect. Electrically induced magnetization switching and detection of
unconventional crystalline components of the anisotropic magnetoresistance are
presented, illustrating the generic utility of the piezo voltage control to
provide new device functionalities and in the research of micromagnetic and
magnetotransport phenomena in diluted magnetic semiconductors.Comment: Submitted to Physical Review Letters. Updates version 1 to include a
more detailed discussion of the effect of strain on the anisotropic
magnetoresistanc
Gnathological features in growing subjects
Aim of this study was to evaluate the prevalence of temporomandibular disorders (TMD) in a sample of consecutive subjects
Ultrasonographic evaluation of three approaches for botulinum toxin injection into tibialis posterior muscle in chronic stroke patients with equinovarus foot: An observational study
Spastic equinovarus (SEV) foot deformity is commonly observed in patients with post-stroke spasticity. Tibialis posterior (TP) is a common target for botulinum toxin type-A (BoNT-A) injection, as a first-line treatment in non-fixed SEV deformity. For this deep muscle, ultrasonographic guidance is crucial to achieving maximum accuracy for the BoNT-A injection. In current clinical practice, there are three approaches to target the TP: an anterior, a posteromedial, and a posterior. To date, previous studies have failed to identify the best approach for needle insertion into TP. To explore the ultrasonographic characteristics of these approaches, we investigated affected and unaffected legs of 25 stroke patients with SEV treated with BoNT-A. We evaluated the qualitative (echo intensity) and quantitative (muscle depth, muscle thickness, overlying muscle, subcutaneous tissue, cross-sectional area) ultrasound characteristics of the three approaches for TP injection. In our sample, we observed significant differences among almost all the parameters of the three approaches, except for the safety window. Moreover, our analysis showed significant differences in cross-sectional area between treated and untreated. Advantages and disadvantages of each approach were investigated. Our findings can thus provide a suitable reference for clinical settings, especially for novice operators
Inflammatory Related Reactions in Humans and in Canine Breast Cancers, A Spontaneous Animal Model of Disease
Inflammatory cells are emerging markers in various cancers in human trials. The relationship between the inflammatory cells response, cancer grade, and progression has been investigated experimentally in a spontaneous canine model of breast cancer and in the unselected population (18–64 years.o.) under anti-HER2 treatments that represent the most prevalent population in this cancer type. The canine data (N samples = 101) were collected retrospectively for diagnosis in our regional area and evaluated by immunohistochemistry and haemato-chemistry. The inflammatory and immune-related adverse reactions (ADR) in humans were evaluated using EudraVigilance. The “Proportional Reporting Ratio” (PRR) of the mabs was calculated for each ADR with values >2 indicative of high risk. In dogs, we found elevated immunostaining of CD68-macrophages in the lymph node of the aggressive cancer G3 and infiltrating CD20+-lymphocyte. A high density of CD20 + lymphocytes was observed in G1 and a decrease in the density was observed with the histological degree of the tumors. The animals with the sample in G1 showed reduced serum platelet and neutrophil count and elevated lymphocytes and the opposite in severely affected animals. Inflammatory reactions with edema, skin reactions, extravasation, loss of effectiveness, and platelet count decrease (PRR > 13) were found with trastuzumab emtansine in humans, in the absence of immune system reactions. Trastuzumab i.v.-s.c. showed immune system reactions, loss of effectiveness, intolerances with drug withdrawal, technological issues (PRR > 7), and neutrophil count decrease reports. These reactions were less frequently reported for pertuzumab i.v. Case reports of platelet and neutrophil count decrease were not associated with disease progression with a better outcome in humans as in canine breast cancer. Therefore, infiltrating CD68-macrophages are associated with G3, while infiltrating CD20+ and elevated serum lymphocytes in parallel with reduced platelet and neutrophil count play a favorable role in human and canine breast cancer
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