203 research outputs found
Peer influence as a driver of technological innovation in the UK National Health Service: a qualitative study of cliniciansâ experiences and attitudes
Background Accelerating innovation to improve quality is a key policy target for healthcare systems around the world. Effectively influencing individualsâ behaviour is crucial to the success of innovation initiatives. This study explores UK cliniciansâ lived experiences of, and attitudes towards, clinical peers endorsing healthcare innovations.
Methods Qualitative interviews with UK-based clinicians in one of two groups: (1) clinicians working in âfront-lineâ service provision and (2) clinicians in strategic leadership roles within health institutions. Participants were identified through purposive sampling, and participated in semistructured telephone interviews. Thematic analysis was used to identify and analyse themes in the data.
Results 17 participants were recruited: eight clinicians from front-line UK healthcare settings and nine clinicians in leadership roles. Two major themes were identified from the interviews: power and trust. Participants recognised and valued peersâ powerful influence, exerted in person via social networks and routine work-related activities. Peers were implicitly trusted, although often on condition of their credibility and deservingness of respect, supporting evidence and absence of conflict of interest. While the groups shared similar views, they diverged on the subject of institutions, felt to be powerful by strategic leaders yet scarcely mentioned by front-line clinicians.
Conclusions UK clinicians view peers as a powerful and trustworthy source to promote innovative technologies. Policies that aim to support this process should seek to control the wider conditions that nurture peer-to-peer influence. Further research into interpersonal influence in health settings may improve implementation of change initiatives
Reply to Comment by Velasco on âHigh-Resolution, Multilayer Modeling of Singaporeâs Urban Climate Incorporating Local Climate Zonesâ
In response to the comment on our paper âHighâresolution, multilayer modeling of Singapore's urban climate incorporating local climate zones,â we provide detailed response to each of the incorrect accusations with scientifically based evidence. We have evaluated our model using all the available observational data, and the results showed good agreement. Our modeling study includes assumptions, as all modeling work does, and we have discussed their rationales and possible implications
Automatic Detection of Malignant Masses in Digital Mammograms Based on a MCET-HHO Approach
Digital image processing techniques have become an important process within medical images. These techniques allow the improvement of the images in order to facilitate their interpretation for specialists. Within these are the segmentation methods, which help to divide the images by regions based on different approaches, in order to identify details that may be complex to distinguish initially. In this work, it is proposed the implementation of a multilevel threshold segmentation technique applied to mammography images, based on the Harris Hawks Optimization (HHO) algorithm, in order to identify regions of interest (ROIs) that contain malignant masses. The method of minimum cross entropy thresholding (MCET) is used to select the optimal threshold values for the segmentation. For the development of this work, four mammography images were used (all with presence of a malignant tumor), in their two views, craniocaudal (CC) and mediolateral oblique (MLO), obtained from the Digital Database for Screening Mammography (DDSM). Finally, the ROIs calculated were compared with the original ROIs of the database through a series of metrics, to evaluate the behavior of the algorithm. According to the results obtained, where it is shown that the agreement between the original ROIs and the calculated ROIs is significantly high, it is possible to conclude that the proposal of the MCET-HHO algorithm allows the automatic identification of ROIs containing malignant tumors in mammography images with significant accuracy.Digital image processing techniques have become an important process within medical images. These techniques allow the improvement of the images in order to facilitate their interpretation for specialists. Within these are the segmentation methods, which help to divide the images by regions based on different approaches, in order to identify details that may be complex to distinguish initially. In this work, it is proposed the implementation of a multilevel threshold segmentation technique applied to mammography images, based on the Harris Hawks Optimization (HHO) algorithm, in order to identify regions of interest (ROIs) that contain malignant masses. The method of minimum cross entropy thresholding (MCET) is used to select the optimal threshold values for the segmentation. For the development of this work, four mammography images were used (all with presence of a malignant tumor), in their two views, craniocaudal (CC) and mediolateral oblique (MLO), obtained from the Digital Database for Screening Mammography (DDSM). Finally, the ROIs calculated were compared with the original ROIs of the database through a series of metrics, to evaluate the behavior of the algorithm. According to the results obtained, where it is shown that the agreement between the original ROIs and the calculated ROIs is significantly high, it is possible to conclude that the proposal of the MCET-HHO algorithm allows the automatic identification of ROIs containing malignant tumors in mammography images with significant accuracy
Restoring Akt1 activity in outgrowth endothelial cells from south asian men rescues vascular reparative potential
Recent data suggest reduced indices of vascular repair in South Asian men, a group at increased risk of cardiovascular events. Outgrowth endothelial cells (OEC) represent an attractive tool to study vascular repair in humans and may offer potential in cell-based repair therapies. We aimed to define and manipulate potential mechanisms of impaired vascular repair in South Asian (SA) men. In vitro and in vivo assays of vascular repair and angiogenesis were performed using OEC derived from SA men and matched European controls, prior defining potentially causal molecular mechanisms. SA OEC exhibited impaired colony formation, migration, and in vitro angiogenesis, associated with decreased expression of the proangiogenic molecules Akt1 and endothelial nitric oxide synthase (eNOS). Transfusion of European OEC into immunodeficient mice after wire-induced femoral artery injury augmented reendothelialization, in contrast with SA OEC and vehicle; SA OEC also failed to promote angiogenesis after induction of hind limb ischemia. Expression of constitutively active Akt1 (E17KAkt), but not green fluorescent protein control, in SA OEC increased in vitro angiogenesis, which was abrogated by a NOS antagonist. Moreover, E17KAkt expressing SA OEC promoted re-endothelialization of wire-injured femoral arteries, and perfusion recovery of ischemic limbs, to a magnitude comparable with nonmanipulated European OEC. Silencing Akt1 in European OEC recapitulated the functional deficits noted in SA OEC. Reduced signaling via the Akt/eNOS axis is causally linked with impaired OEC-mediated vascular repair in South Asian men. These data prove the principle of rescuing marked reparative dysfunction in OEC derived from these men.This work was supported by the British Heart Foundation, London, UK, and the Diabetes Research and Wellness Foundation, Portsmouth, UK
Broken R Parity Contributions to Flavor Changing Rates and CP Asymmetries in Fermion Pair Production at Leptonic Colliders
We examine the effects of the R parity odd renormalizable interactions on
flavor changing rates and CP violation asymmetries in the production of
fermion-antifermion pairs at leptonic colliders. The produced
fermions may be leptons, down-quarks or up-quarks, and the center of mass
energies may range from the Z-boson pole up to GeV. Off the Z-boson
pole, the flavor changing rates are controlled by tree level amplitudes and the
CP asymmetries by interference terms between tree and loop level amplitudes. At
the Z-boson pole, both observables involve loop amplitudes. The lepton number
violating interactions, associated with the coupling constants, \l_{ijk},
\l'_{ijk}, are only taken into account. The consideration of loop amplitudes
is restricted to the photon and Z-boson vertex corrections. We briefly review
flavor violation physics at colliders. We present numerical results using a
single, species and family independent, mass parameter, , for all the
scalar superpartners and considering simple assumptions for the family
dependence of the R parity odd coupling constants.Comment: Latex File. 23 pages. 4 postscript figures. 1 table. Revised version
with new results and several corrections in numerical result
VEGF-A isoforms program differential VEGFR2 signal transduction, trafficking and proteolysis
Vascular endothelial growth factor A (VEGF-A) binding to the receptor tyrosine kinase VEGFR2 triggers multiple signal transduction pathways, which regulate endothelial cell responses that control vascular development. Multiple isoforms of VEGF-A can elicit differential signal transduction and endothelial responses. However, it is unclear how such cellular responses are controlled by isoform-specific VEGF-A-VEGFR2 complexes. Increasingly, there is the realization that the membrane trafficking of receptor-ligand complexes influences signal transduction and protein turnover. By building on these concepts, our study shows for first time that three different VEGF-A isoforms (VEGF-A165, VEGF-A121 and VEGF-A145) promote distinct patterns of VEGFR2 endocytosis for delivery into early endosomes. This differential VEGFR2 endocytosis and trafficking is linked to VEGF-A isoform-specific signal transduction events. Disruption of clathrin-dependent endocytosis blocked VEGF-A isoform-specific VEGFR2 activation, signal transduction and caused substantial depletion in membrane-bound VEGFR1 and VEGFR2 levels. Furthermore, such VEGF-A isoforms promoted differential patterns of VEGFR2 ubiquitination, proteolysis and terminal degradation. Our study now provides novel insights into how different VEGF-A isoforms can bind the same receptor tyrosine kinase and elicit diverse cellular outcomes
Optoelectronic characterization of CuInGa(S)2 thin films grown by spray pyrolysis for photovoltaic application
[EN] Copper-indium gallium disulfide (CIGS) is a good absorber for photovoltaic application. Thin films of CIGS were prepared by spray pyrolysis on glass substrates in the ambient atmosphere. The films were characterized by different techniques, such as structural, morphological, optical and electrical properties of CIGS films were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), spectrophotometer and Hall effect, respectively. After optimization, the deposited films structure, grain size, and crystallinity became more important with an increase of annealing time at 370 degrees C for 20 min. Transmission electron microscopy (TEM) analysis shows that the interface sheets are well crystallized and the inter planer distance are 0.25 nm, 0.28 nm, and 0.36 nm. The atomic force microscopy (AFM) observation shows that the grain size and roughness can be tolerated by optimizing the annealing time. The strong absorbance and low transmittance were observed for the prepared films with a suitable energy bandgap about 1.46 eV. The Hall effect measurement system examined that CIGS films exhibited optimal electrical properties, resistivity, carrier mobility, and carrier concentration which were determined to be 4.22 x 10(6) omega cm, 6.18 x 10(2) cm(2) V-1 S-1 and 4.22 x 10(6) cm(-3), respectively. The optoelectronic properties of CIGS material recommended being used for the photovoltaic application.Prof. Bouchaib HARTITI, The Senior Associate at ICTP, is very grateful to ICTP for permanent support. Prof. Mohamed Ebn Touhami, Director of the University Center for Analysis, Expertise, Transfer of Technology and Incubation, Kenitra, Morocco, is very grateful to CUA2TI for financial support. Thanks to Doctor Diogo M.F. Santos for the supervision of Amal Bouich's work during her research in CeFEMA research center. 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Turki, Characteristics of CuIn1â xGaxS2 thin films synthesized by chemical spray pyrolysis. J. Lumin. 150, 1â7 (2014)B.J. Babu, S. Velumani, A. Kassiba, R. Asomoza, J.A. Chavez-Carvayar, J. Yi, Deposition and characterization of graded Cu (In1-xGax) Se2 thin films by spray pyrolysis. Mater. Chem. Phys. 162, 59â68 (2015)S.F. Varol, G. BabĂŒr, G. Ăankaya, U. Kölemen, Synthesis of solâgel derived nano-crystalline ZnO thin films as TCO window layer: effect of sol aging and boron. RSC Adv. 4(100), 56645â56653 (2014)J.A. Frantz, R.Y. Bekele, V.Q. Nguyen, J.S. Sanghera, A. Bruce, S.V. Frolov, I.D. Aggarwal, Cu (In, Ga) Se2 thin films and devices sputtered from a single target without additional selenization. Thin Solid Films 519(22), 7763â7765 (2011)C. CalderĂłn, G. Gordillo, P. Bartolo-PĂ©rez, F. Mesa, Effect of the deposition conditions on the optical, morphological and compositional properties of CuIn1â xGaxSe2 thin films prepared by a multistage process. 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Optik 183, 137â147 (2019
Geology and combustion perspectives of Pakistani coals from Salt Range and Trans Indus Range
Abundant availability of low rank coals in some developing countries has a great potential for socio-economic development. Pakistan, as a developing country, has taken a number of initiatives some of which are at an advanced stage. Thus, a critical study of regional and local geology of Salt Range and Trans Indus Range coals located in the KohatâPotwar geologic province is presented in this paper. Permian coal is the oldest coal, which is located in the Western Salt Range in limited quantity while Palaeocene coal is the younger coal and it is mined from the Hangu and Patala formations. The Palaeocene coal is available in abundance and is mined in the Eastern and Central parts of the Salt Range and Trans Indus Range.
Additionally, this study presents the thermo-chemical analyses of the coal samples collected from thirty coal mines of Salt Range and Trans Indus Range. The samples were analyzed for ash composition, ash fusion temperatures (AFT), proximate analysis, ultimate analysis and calorific value from two different Labs, i.e. SGS Pakistan and Changsha University of Science and Technology (CUST), China. The average AFT of the samples analyzed is > 1350 °C, which reveals that the coal is non-slagging. On average the coal has low slagging index, medium fouling index, good combustion characteristic parameters and indices. The coal samples have high ash (14â50%), ultra-high sulfur (3.3â11.1%), low moisture (3â10%), high volatile matter (VM, 24â41%), low carbon (23â57%) with low to medium gross calorific value (GCV, 10.2â25.7 MJ/kg).
The data gathered from an extensive campaign is compared with the already published data. The study has provided a knowledge on utilization of coal reserves to meet the projected energy demand in Pakistan as well as in other developing countries
Variability in detection of SARS-CoV-2-specific antibody responses following mild infection: a prospective multicentre cross-sectional study, London, United Kingdom, 17 April to 17 July 2020
Introduction Immunoassays targeting different SARS-CoV-2-specific antibodies are employed for seroprevalence studies. The degree of variability between immunoassays targeting anti-nucleocapsid (anti-NP; the majority) vs the potentially neutralising anti-spike antibodies (including anti-receptor-binding domain; anti-RBD), particularly in mild or asymptomatic disease, remains unclear. Aims We aimed to explore variability in anti-NP and anti-RBD antibody detectability following mild symptomatic or asymptomatic SARS-CoV-2 infection and analyse antibody response for correlation with symptomatology. Methods A multicentre prospective cross-sectional study was undertaken (AprilâJuly 2020). Paired serum samples were tested for anti-NP and anti-RBD IgG antibodies and reactivity expressed as binding ratios (BR). Multivariate linear regression was performed analysing age, sex, time since onset, symptomatology, anti-NP and anti-RBD antibody BR. Results We included 906 adults. Antibody results (793/906; 87.5%; 95% confidence interval: 85.2â89.6) and BR strongly correlated (Ïâ=â0.75). PCR-confirmed cases were more frequently identified by anti-RBD (129/130) than anti-NP (123/130). Anti-RBD testing identified 83 of 325 (25.5%) cases otherwise reported as negative for anti-NP. Anti-NP presence (+1.75/unit increase; pâ<â0.001), fever (â„â38°C;â+1.81; pâ<â0.001) or anosmia (+1.91; pâ<â0.001) were significantly associated with increased anti-RBD BR. Age (pâ=â0.85), sex (pâ=â0.28) and cough (pâ=â0.35) were not. When time since symptom onset was considered, we did not observe a significant change in anti-RBD BR (pâ=â0.95) but did note decreasing anti-NP BR (pâ<â0.001). Conclusion SARS-CoV-2 anti-RBD IgG showed significant correlation with anti-NP IgG for absolute seroconversion and BR. Higher BR were seen in symptomatic individuals, particularly those with fever. Inter-assay variability (12.5%) was evident and raises considerations for optimising seroprevalence testing strategies/studies
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