416 research outputs found
Efficacy of dignity therapy for depression and anxiety in terminally-ill patients: early results of a randomized controlled trial
Objective: Dignity therapy (DT) is a short-term psychotherapy developed for patients living with a life-limiting illness. Our aim was to determine the influence of DT on symptoms of depression and anxiety in people with a life-threatening disease with high level of distress, referred to an inpatient palliative care unit.
Method: This was an open-label randomized controlled trial. Sixty terminally ill patients were randomly assigned to one of two groups: intervention group (DT+ standard palliative care [SPC]) or control group (SPC alone). The main outcomes were symptoms of depression and anxiety, measured with the Hospital Anxiety and Depression Scale, assessed at baseline, day 4, day 15, and day 30 of follow-up.
Results: Of the 60 participants, 29 were randomized to DT and 31 to SPC. Baseline characteristics were similar between the two groups. DT was associated with a significant decrease in depressive symptoms at day 4 and day 15 (mean = −4.46, 95% CI, −6.91–2.02, p = 0.001; mean= −3.96, 95% CI, −7.33 to −0.61; p = 0.022, respectively), but not at day 30 (mean = −3.33, 95% CI, −7.32–0.65, p = 0.097). DT was also associated with a significant decrease in anxiety symptoms at each follow-up (mean= −3.96, 95% CI, −6.66 to −1.25, p = 0.005; mean= −6.19, 95% CI, −10.49 to −1.88, p = 0.006; mean = −5.07, 95% CI, −10.22 to −0.09, p = 0.054, respectively).
Significance of results: DT appears to have a short-term beneficial effect on the depression and anxiety symptoms that often accompany patients at the end of their lives. Future research with larger samples compared with other treatments is needed to better understand the potential benefits of this psychotherapy
Scanning-gate microscopy of semiconductor nanostructures: an overview
This paper presents an overview of scanning-gate microscopy applied to the
imaging of electron transport through buried semiconductor nanostructures.
After a brief description of the technique and of its possible artifacts, we
give a summary of some of its most instructive achievements found in the
literature and we present an updated review of our own research. It focuses on
the imaging of GaInAs-based quantum rings both in the low magnetic field
Aharonov-Bohm regime and in the high-field quantum Hall regime. In all of the
given examples, we emphasize how a local-probe approach is able to shed new, or
complementary, light on transport phenomena which are usually studied by means
of macroscopic conductance measurements.Comment: Invited talk by SH at 39th "Jaszowiec" International School and
Conference on the Physics of Semiconductors, Krynica-Zdroj, Poland, June 201
Transport inefficiency in branched-out mesoscopic networks: An analog of the Braess paradox
We present evidence for a counter-intuitive behavior of semiconductor
mesoscopic networks that is the analog of the Braess paradox encountered in
classical networks. A numerical simulation of quantum transport in a two-branch
mesoscopic network reveals that adding a third branch can paradoxically induce
transport inefficiency that manifests itself in a sizable conductance drop of
the network. A scanning-probe experiment using a biased tip to modulate the
transmission of one branch in the network reveals the occurrence of this
paradox by mapping the conductance variation as a function of the tip voltage
and position.Comment: 2nd version with minor stylistic corrections. To appear in Phys. Rev.
Lett.: Editorially approved for publication 6 January 201
Intra-hospital mortality for community-acquired pneumonia in mainland Portugal between 2000 and 2009
Introduction: Community-acquired pneumonia (CAP) remains a common and serious infection with wide variability in intra-hospital mortality.
Methods: We performed a retrospective analysis of adult patients admitted with CAP in mainland Portugal between the years 2000 and 2009.
Results: The intra-hospital mortality rate was 20.4% with deaths in all age groups. The average age of deceased patients was 79.8 years, significantly higher than surviving patients with 71.3 years. Patients aged 50 or more presented a relative risk of death 4.4 times the risk of patients under this age group. Likewise, in patients aged 65 or more the risk of death was 3.2 times the risk of patients <65 years. Men died more at a younger age than women, the men who died were, on average, 4 years younger than women, 78.1 vs 82.1 years old. Relative risk of death in men was 17% higher than women after adjustment for year of admission and age.
Conclusion: CAP remains an important cause of hospital mortality in all age groups.info:eu-repo/semantics/publishedVersio
The impact of vaccination on the evolution of COVID-19 in Portugal
DOCTORATES 4 COVID-19", number 2020.10172.BD. PP UIDB/00297/2020 UIDB/04621/2020 UIDP/04621/2020In this work we use simple mathematical models to study the impact of vaccination against COVID-19 in Portugal. First, we fit a SEIR type model without vaccination to the Portuguese data on confirmed cases of COVID-19 by the date of symptom onset, from the beginning of the epidemic until the 23rd January of 2021, to estimate changes in the transmission intensity. Then, by including vaccination in the model we develop different scenarios for the fade-out of the non pharmacological intervention (NPIs) as vaccine coverage increases in the population according to Portuguese vaccination goals. We include a feedback function to mimic the implementation and relaxation of NPIs, according to some disease incidence thresholds defined by the Portuguese health authorities.publishersversionpublishe
A dive into the bath: embedded 3D bioprinting of freeform in vitro models
Designing functional, vascularized, human scale in vitro models with biomimetic architectures and multiple cell types is a highly promising strategy for both a better understanding of natural tissue/organ development stages to inspire regenerative medicine, and to test novel therapeutics on personalized microphysiological systems. Extrusion-based 3D bioprinting is an effective biofabrication technology to engineer living constructs with predefined geometries and cell patterns. However, bioprinting high-resolution multilayered structures with mechanically weak hydrogel bioinks is challenging. The advent of embedded 3D bioprinting systems in recent years offered new avenues to explore this technology for in vitro modeling. By providing a stable, cell-friendly and perfusable environment to hold the bioink during and after printing, it allows to recapitulate native tissues’ architecture and function in a well-controlled manner. Besides enabling freeform bioprinting of constructs with complex spatial organization, support baths can further provide functional housing systems for their long-term in vitro maintenance and screening. This minireview summarizes the recent advances in this field and discuss the enormous potential of embedded 3D bioprinting technologies as alternatives for the automated fabrication of more biomimetic in vitro models.The authors acknowledge the financial support from Project NORTE-01-0145-FEDER 000021 supported by Norte Portugal Regional Operational Program (NORTE 2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF), the European Union Framework Program for Research and Innovation HORIZON 2020, under European Research Council Grant Agreement 772817 and 101069302, Fundação para a Ciência e a Tecnologia (FCT) for the for Contract 2020.03410.CEECIND (to R. M. A. D.) and Wi-Pi project 2022.05526.PTDC. The schematics of the Table of Contents graphic was created with BioRender.com
Polycrystalline Ni nanotubes under compression: a molecular dynamics study
Mechanical properties of nanomaterials, such as nanowires and nanotubes, are an important feature for the design of novel electromechanical nano-architectures. Since grain boundary structures and surface modifications can be used as a route to modify nanostructured materials, it is of interest to understand how they affect material strength and plasticity. We report large-scale atomistic simulations to determine the mechanical response of nickel nanowires and nanotubes subject to uniaxial compression. Our results suggest that the incorporation of nanocrystalline structure allows completely flexible deformation, in sharp contrast with single crystals. While crystalline structures at high compression are dominated by dislocation pinning and the multiplication of highly localized shear regions, in nanocrystalline systems the dislocation distribution is significantly more homogeneous. Therefore, for large compressions (large strains) coiling instead of bulging is the dominant deformation mode. Additionally, it is observed that nanotubes with only 70% of the nanowire mass but of the same diameter, exhibit similar mechanical behavior up to 0.3 strain. Our results are useful for the design of new flexible and light-weight metamaterials, when highly deformable struts are required.Fil: Rojas Nunez, J.. Universidad de Santiago de Chile; ChileFil: Baltazar, S. E.. Universidad de Santiago de Chile; ChileFil: Gonzalez, R. I.. Universidad Mayor; ChileFil: Bringa, Eduardo Marcial. Universidad Mayor; Chile. Universidad de Mendoza. Facultad de IngenierÃa; Argentina. Consejo Nacional de Investigaciones CientÃficas y Técnicas; ArgentinaFil: Allende, S.. Universidad de Santiago de Chile; ChileFil: Kiwi, M.. Universidad de Santiago de Chile; ChileFil: Valencia, F. J.. Universidad de Santiago de Chile; Chile. Universidad Mayor; Chil
Li+ Influx and Binding, and Li+/Mg2+ Competition in Bovine Chromaffin Cell Suspensions as Studied by 7Li NMR and Fluorescence Spectroscopy
Li+ influx by bovine chromaffin cells, obtained from bovine adrenal medulla, was studied in intact cell suspensions using 7Li NMR spectroscopy with the shift reagent [Tm(HDOTP)]4-. The influx rate constants, ki, were determined in the absence and in the presence of two Na+ membrane transport inhibitors. The values obtained indicate that both voltage sensitive Na+ channels and (Na+/K+)-ATPase play an important role in Li+ uptake by these cells. 7Li NMR T1 and T2 relaxation times for intracellular Li+ in bovine chromaffin cells provided a T1/T2 ratio of 305, showing that Li+ is highly, immobilized due to strong binding to intracellular structures. Using fluorescence spectroscopy and the Mg2+ fluorescent probe, furaptra, the free intracellular Mg2+ concentration in the bovine chromaffin cells incubated with 15 mM LiCl was found to increase by about mM after the intracellular Li+ concentration reached a steady state. Therefore, once inside the cell, Li+ is able to displace Mg2+ from its binding sites
Planning the electron traffic in semiconductor networks: A mesoscopic analog of the Braess paradox encountered in road networks
By combining quantum simulations of electron transport and scanning-gate
microscopy, we have shown that the current transmitted through a semiconductor
two-path rectangular network in the ballistic and coherent regimes of transport
can be paradoxically degraded by adding a third path to the network. This is
analogous to the Braess paradox occurring in classical networks. Simulations
reported here enlighten the role played by congestion in the network.Comment: 31st Int. Conf. Phys. Semiconductors, Zurich, July-August 201
Metal ion-zeolite nanomaterials for chemodynamic therapy
A new therapeutic approach called chemodynamic therapy (CDT), which can be defined as specific OH generation in cancer cells via Fenton reactions, was recently proposed.1 The advantages of CDT can be ascribed to the higher specificity, no external field penetration depth restriction, lower side effects in normal tissues, higher-level ROS generation, lack of equipment restrictions, and non-multidrug resistance, showing the promising future of CDT for clinical translation. The varied and highly controlled structural along with the chemical properties of inorganic
nanomaterials, like zeolites, make them suitable for this type of CDT. Zeolites already proved to be interesting
candidates for medical and healthcare applications, and also as Fenton heterogeneous catalysts for organic degradation. The aim of this study was to assess the dual activity (antibacterial and anticancer) of metal ion-zeolite nanomaterials. The prepared metal ion-zeolite nanomaterials were tested in vitro using a human skin cancer cell line, A375, and the anti-bacterial activity was evaluated against Escherichia coli, Staphylococcus aureus and MRSA.
Results obtained so far suggest that metal ion-zeolite nanomaterials could be explored as antibacterial and/or anticancer agents.info:eu-repo/semantics/publishedVersio
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