299,478,380 research outputs found
Assessment of biventricular function by three-dimensional speckle tracking echocardiography in adolescents and young adults with human immunodeficiency virus infection. a pilot study.
Background. The purpose of the study was to assess biventricular parameters of wall deformation with three-dimensional speckle tracking echocardiography (3DSTE) in adolescents and young adults with human immunodeficiency virus infection (HIV) on antiretroviral therapy in order to detect a possible subclinical myocardial dysfunction. Methods. Twenty-one patients aged 12 to 39years with HIV, 21 normal controls of the same age and sex, and 21 patients with idiopathic non-ischemic dilated cardiomyopathy (DCM) were studied with 3DSTE. All HIV patients were stable in terms of HIV infection, with no history of heart disease or other chronic systemic disease except HIV infection, and were on highly active antiretroviral therapy (HAART) with good immunological control. Standard echocardiographic measures of LV-RV function were assessed. 3D LV global longitudinal strain (GLS), circumferential strain, radial strain and LV twist (TW) were calculated. Global area strain (GAS) was calculated by 3DSTE as percentage variation in surface area defined by the longitudinal and circumferential strain vectors. 3D right ventricular (RV) global and free-wall longitudinal strain were obtained. Results. LV GLS and GAS were lower in HIV patients compared to normal controls (p=0.002, and p=0.01, respectively). There were no significant differences in LV ejection fractions between the groups. There was a weak positive correlation between LV GLS and age (r=0.215, p=0.034) and a weak negative correlation between LV GLS and nadir-CD4 T-cells count (r=0.198, p=0.043). DCM patients had more marked and widespread reduction in LV GLS and GAS compared to controls (p<0.001), whereas in HIV patients LV strain impairment (p<0.05) was more localized in basal and apical regions. RV free-wall longitudinal strain was significantly reduced in HIV patients when compared with the control group (p=0.03). No patient had pulmonary systolic pressure higher than 35mmHg. Conclusions. Three-dimensional speckle tracking echocardiography may help to identify HIV patients at high cardiovascular risk allowing early detection of biventricular dysfunction in the presence of normal LV ejection fraction and in the absence of pulmonary hypertension. LV strain impairment in HIV patients is less prominent and widespread compared to DCM patients
A BIM-based PSS approach for the management of maintenance operations of building equipment
The service-centered economy has grown considerably in the last few years, shifting from product-based solutions towards service centered offerings, i.e., Product-Service System (PSS) solutions. Such an approach is also emerging in the context of building equipment, where maintenance activities play a fundamental role in facility management. In this field, Building Information Modeling (BIM) based tools are diffusely used to improve the performances of facility management. However, few studies have addressed the above issues while considering a shift from product-based approaches in favor of more advanced servitization models. The study aims at integrating BIM based approaches in a PSS context for the improvement of the management of maintenance operations of building equipment. A general framework for maintenance management has been developed, merging the implementation of the PSS components in a BIM model for the definition of maintenance management. A first application of this methodology to a real case study concerning the elevators of an existing building has shown the efficacy of the proposed approach. The study highlighted the benefits that can be achieved, especially in terms of reduced periods of equipment unavailability, reduced costs and augmented customer satisfaction, while enhancing the information exchange between the PSS actors. Hence, although further research is still needed for its validation, the proposed approach can offer practical insights for the development of promising BIM-based PSS solutions for facility management in the construction industry
Activity of eribulin mesylate in brain metastasis from breast cancer. a stone in a pond?
Background: Brain metastases develop in approximately 10-25% of patients with metastatic breast cancer (MBC) and are associated with a very poor prognosis. Case Report: We report the case of a 40-year-old woman with MBC and associated lung, bone, liver, and brain metastases, who experienced a time to progression of several months with eribulin after whole-brain radiotherapy (WBRT), 2 lines of chemotherapy, and 1 line of hormonal therapy, maintaining a good toxicity profile. Discussion: Eribulin, in association with local treatment such as WBRT, can be well tolerated and effective in achieving a long progression-free survival and a good control of brain metastases in patients with MBC who have received multiple lines of treatment. The vascular remodeling properties of eribulin, combined with brain radiotherapy, might facilitate the passage of eribulin across the blood brain barrier, improving brain response. Conclusion: Our anecdotal experience suggests that eribulin may have a potentially beneficial effect on brain metastases while maintaining a good systemic control of the disease in patients with MBC
Analysis of short-term blood pressure variability in pheochromocytoma/paraganglioma patients
Data on short-term blood pressure variability (BPV), which is a well-established cardiovascular prognostic tool, in pheochromocytoma and paraganglioma (PPGL) patients is still lack and conflicting. We retrospectively evaluated 23 PPGL patients referred to our unit from 2010 to 2019 to analyze 24 h ambulatory blood pressure monitoring (24-h ABPM)-derived markers of short-term BPV, before and after surgical treatment. PPGL diagnosis was assessed according to guidelines and confirmed by histologic examination. The 24-h ABPM-derived markers of short-term BPV included: circadian pressure rhythm; standard deviation (SD) and weighted SD (wSD) of 24-h, daytime, and night-time systolic and diastolic blood pressure (BP); average real variability (ARV) of 24-h, daytime, and night-time systolic and diastolic BP. 7 males and 16 females of 53 ± 18 years old were evaluated. After surgical resection of PPGL we found a significant decrease in 24-h systolic BP ARV (8.8 ± 1.6 vs. 7.6 ± 1.3 mmHg, p < 0.001), in 24-h diastolic BP ARV (7.5 ± 1.6 vs. 6.9 ± 1.4 mmHg, p = 0.031), and in wSD of 24-h diastolic BP (9.7 ± 2.0 vs 8.8 ± 2.1 mmHg, p = 0.050) comparing to baseline measurements. Moreover, baseline 24-h urinary metanephrines significantly correlated with wSD of both 24-h systolic and diastolic BP. Our study highlights as PPGL patients, after proper treatment, show a significant decrease in some short-term BPV markers, which might represent a further cardiovascular risk factor
Signal yields, energy resolution, and recombination fluctuations in liquid xenon
This work presents an analysis of monoenergetic electronic recoil peaks in
the dark-matter-search and calibration data from the first underground science
run of the Large Underground Xenon (LUX) detector. Liquid xenon charge and
light yields for electronic recoil energies between 5.2 and 661.7 keV are
measured, as well as the energy resolution for the LUX detector at those same
energies. Additionally, there is an interpretation of existing measurements and
descriptions of electron-ion recombination fluctuations in liquid xenon as
limiting cases of a more general liquid xenon re- combination fluctuation
model. Measurements of the standard deviation of these fluctuations at
monoenergetic electronic recoil peaks exhibit a linear dependence on the number
of ions for energy deposits up to 661.7 keV, consistent with previous LUX
measurements between 2-16 keV with H. We highlight similarities in liquid
xenon recombination for electronic and nuclear recoils with a comparison of
recombination fluctuations measured with low-energy calibration data.Comment: 11 pages, 12 figures, 3 table
Hard Lefschetz for Chow groups of generalized Kummer varieties
The main result of this note is a hard Lefschetz theorem for the Chow groups
of generalized Kummer varieties. The same argument also proves hard Lefschetz
for Chow groups of Hilbert schemes of abelian surfaces. As a consequence, we
obtain new information about certain pieces of the Chow groups of generalized
Kummer varieties, and Hilbert schemes of abelian surfaces. The proofs are based
on work of Shen-Vial and Fu-Tian-Vial on multiplicative Chow-K\"unneth
decompositions.Comment: 9 pages, to appear in Abh. Math. Semin. Univ. Hambg., comments
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Exploring the environment, discovering learning resources and creating low cost training and development
School of Managemen
Provisional assessment of the potential use of the Physical Habitat Simulation (PHABSIM) system to assess the impact of flow modification on juvenile fish habitat in the River Thames
The Mersey Estuary : sediment geochemistry
This report describes a study of the geochemistry of
the Mersey estuary carried out between April 2000 and
December 2002. The study was the first in a new programme
of surveys of the geochemistry of major British estuaries
aimed at enhancing our knowledge and understanding of the
distribution of contaminants in estuarine sediments.
The report first summarises the physical setting, historical
development, geology, hydrography and bathymetry of the
Mersey estuary and its catchment. Details of the sampling
and analytical programmes are then given followed by a
discussion of the sedimentology and geochemistry. The
chemistry of the water column and suspended particulate
matter have not been studied, the chief concern being with
the geochemistry of the surface and near-surface sediments
of the Mersey estuary and an examination of their likely
sources and present state of contamination
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