292 research outputs found

    Productivity Enhancement in Directed Energy Deposition: The Oscillating Scanning Strategy Approach

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    Directed Energy Deposition (DED) is an additive manufacturing process that enables the production of large metal components by melting the feedstock material while being deposited. An improvement of the production speed of this process would further increase its applicability in many industrial fields. The DED building rate is strictly related to the building parameters adopted, in particular to the laser spot diameter, which also affects the build accuracy and the surface quality of the components. The possibility of using a variable laser spot would result in a significant increase in the production rate in bulky zones, while also providing a good surface quality where needed. In the present work, an oscillating scanning strategy was used to create a large apparent laser spot (+ 170% of the nominal value) to produce 316L stainless steel samples via DED. The optimisation of the DED parameters with the oscillating strategy was performed using the single scan tracks (SSTs) approach. The morphologies of the SSTs obtained with different process parameters were assessed and the geometrical features related to the melt pools were analysed in order to select the most suitable X and Z displacements for the production of the cubic samples. The analyses of the cubes revealed that, if the correct overlap among nearby scans is selected, it is possible to obtain dense samples with all the oscillating diameters tested. Finally, comparing the building rate and powder efficiency values confirmed that this method can accelerate the building process and improve its overall performance

    Labor Analgesia. A Systematic Review and Meta-Analysis of Non-Pharmacological Complementary and Alternative Approaches to Pain during First Stage of Labor

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    The aim of the study was to conduct a meta-analysis to evaluate the efficacy of non-invasive and nonpharmacological techniques on labor first-stage pain intensity. Literature databases were searched from inception to May 2021, and research was expanded through the screening of previous systematic reviews. Inclusion criteria were: (1) population: women in first stage of labor; (2) intervention: non-pharmacological, non-invasive, or minimally invasive intrapartum analgesic techniques alternative and/or complementary to pharmacological analgesia; (3) comparison: routine intrapartum care or placebos; (4) outcomes: subjective pain intensity; and (5) study design: randomized controlled trial. Risk of bias of included studies was investigated, data analysis was performed using R version 3.5.1. Effect size was calculated as difference between the control and experimental groups at posttreatment in terms of mean pain score. A total of 63 studies were included, for a total of 6146 patients (3468 in the experimental groups and 2678 in the control groups). Techniques included were massage (n = 11), birth balls (n = 5) mind-body interventions (n = 8), heat application (n = 12), music therapy (n = 9), dance therapy (n = 2), acupressure (n = 16), and transcutaneous electrical nerve stimulation (TENS) (n = 8). The present review found significant evidence in support of the use of complementary and alternative medicine for labor analgesia, and different methods showed different impact. However, more high-quality trials are needed

    Economic impact of remote monitoring on ordinary follow-up of implantable cardioverter defibrillators as compared with conventional in-hospital visits: a single-center prospective and randomized study

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    Few data are available on actual follow-up costs of remote monitoring (RM) of implantable defibrillators (ICD). Our study aimed at assessing current direct costs of 1-year ICD follow-up based on RM compared with conventional quarterly in-hospital follow-ups. Methods and results Patients (N=233) with indications for ICD were consecutively recruited and randomized at implant to be followed up for 1 year with standard quarterly inhospital visits or by RM with one in-hospital visit at 12 months, unless additional in-hospital visits were required due to specific patient conditions or RM alarms. Costs were calculated distinguishing between provider and patient costs, excluding RM device and service cost. The frequency of scheduled in-hospital visits was lower in the RM group than in the control arm. Follow-up required 47 min per patient/year in the RM arm versus 86 min in the control arm (p=0.03) for involved physicians, generating cost estimates for the provider of USD 45 and USD 83 per patient/- year, respectively. Costs for nurses were comparable. Overall, the costs associated with RM and standard follow-up were USD 103±27 and 154±21 per patient/year, respectively (p=0.01). RM was cost-saving for the patients: USD 97±121 per patient/year in the RM group versus 287± 160 per patient/year (p=0.0001). Conclusion The time spent by the hospital staff was significantly reduced in the RM group. If the costs for the device and service are not charged to patients or the provider, patients could save about USD 190 per patient/year while the hospital could save USD 51 per patient/year

    Virtual reality for the assessment of everyday cognitive functions in older adults: an evaluation of the virtual reality action test and two interaction devices in a 91-year-old woman

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    Performance-based functional tests for the evaluation of daily living activities demonstrate strong psychometric properties and solve many of the limitations associated with self- and informant-report questionnaires. Virtual reality (VR) technology, which has gained interest as an effective medium for administering interventions in the context of healthcare, has the potential to minimize the time-demands associated with the administration and scoring of performance-based assessments. To date, efforts to develop VR systems for assessment of everyday function in older adults generally have relied on non-immersive systems. The aim of the present study was to evaluate the feasibility of an immersive VR environment for the assessment of everyday function in older adults. We present a detailed case report of an elderly woman who performed an everyday activity in an immersive VR context (Virtual Reality Action Test) with two different types of interaction devices (controller vs. sensor). VR performance was compared to performance of the same task with real objects outside of the VR system (Real Action Test). Comparisons were made on several dimensions, including (1) quality of task performance (e.g., order of task steps, errors, use and speed of hand movements); (2) subjective impression (e.g., attitudes), and (3) physiological markers of stress. Subjective impressions of performance with the different controllers also were compared for presence, cybersickness, and usability. Results showed that the participant was capable of using controllers and sensors to manipulate objects in a purposeful and goal-directed manner in the immersive VR paradigm. She performed the everyday task similarly across all conditions. She reported no cybersickness and even indicated that interactions in the VR environment were pleasant and relaxing. Thus, immersive VR is a feasible approach for function assessment even with older adults who might have very limited computer experience, no prior VR exposure, average educational experiences, and mild cognitive difficulties. Because of inherent limitations of single case reports (e.g., unknown generalizability, potential practice effects, etc.), group studies are needed to establish the full psychometric properties of the Virtual Reality Action Test

    Complications following non-surgical aesthetic treatments in hiv+ patients receiving antiretroviral therapy: A 12-years experience

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    Since the advent of HIV antiretroviral therapies at the end of the 20th century, the morbidity and mortality rates associated with HIV infection have decreased dramatically. Unfortunately, these benefits are associated with substantial morphologic changes in the body, such as abnormal fat distribution with peripheral lipohypertrophy and facial lipoatrophy. Facial wasting is considered the major stigma for HIV–infected people and may result in reduced antiretroviral adherence. Patients suffering from the stigmata of HIV infection can benefit from non-surgical aesthetic treatments performed with fillers or lipolytic agents that provide a quick and reliable service for facial rejuvenation, with high patient satisfaction and a low risk of complications. In the present paper, a retrospective analysis of complications following non-surgical aesthetic treatments (calcium hydroxyapatite-based filler, hyaluronic acid filler, polyacrylamide hydrogel filler and dehoxycholic acid injections), in a cohort of 116 consecutive HIV+ patients, treated over a period of 12 years, was performed. With the exception of the tardive swelling reported after calcium hydroxyapatite injections, complications were recorded just after polyacrylamide hydrogel treatment as small, palpable, nonvisible nodules or aseptic abscess. Our experience is consistent with those already published in the literature and the complication rate seems to be comparable to non-infected patients

    Soil and water bioengineering: practice and research needs for reconciling natural hazard control and ecological restoration

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    Soil and water bioengineering is a technology that encourages scientists and practitioners to combine their knowledge and skills in the management of ecosystems with a common goal to maximize benefits to both man and the natural environment. It involves techniques that use plants as living building materials, for: (i) natural hazard control (e.g., soil erosion, torrential floods and landslides) and (ii) ecological restoration or nature-based re-introduction of species on degraded lands, river embankments, and disturbed environments. For a bioengineering project to be successful, engineers are required to highlight all the potential benefits and ecosystem services by documenting the technical, ecological, economic and social values. The novel approaches used by bioengineers raise questions for researchers and necessitate innovation from practitioners to design bioengineering concepts and techniques. Our objective in this paper, therefore, is to highlight the practice and research needs in soil and water bioengineering for reconciling natural hazard control and ecological restoration. Firstly, we review the definition and development of bioengineering technology, while stressing issues concerning the design, implementation, and monitoring of bioengineering actions. Secondly, we highlight the need to reconcile natural hazard control and ecological restoration by posing novel practice and research questions

    Biphasic Oxidation of Oxy-Hemoglobin in Bloodstains

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    Background: In forensic science, age determination of bloodstains can be crucial in reconstructing crimes. Upon exiting the body, bloodstains transit from bright red to dark brown, which is attributed to oxidation of oxy-hemoglobin (HbO2) to methemoglobin (met-Hb) and hemichrome (HC). The fractions of HbO 2, met-Hb and HC in a bloodstain can be used for age determination of bloodstains. In this study, we further analyze the conversion of HbO2 to met-Hb and HC, and determine the effect of temperature and humidity on the conversion rates. Methodology: The fractions of HbO2, met-Hb and HC in a bloodstain, as determined by quantitative analysis of optical reflectance spectra (450–800 nm), were measured as function of age, temperature and humidity. Additionally, Optical Coherence Tomography around 1300 nm was used to confirm quantitative spectral analysis approach. Conclusions: The oxidation rate of HbO2 in bloodstains is biphasic. At first, the oxidation of HbO2 is rapid, but slows down after a few hours. These oxidation rates are strongly temperature dependent. However, the oxidation of HbO2 seems to be independent of humidity, whereas the transition of met-Hb into HC strongly depends on humidity. Knowledge of these decay rates is indispensable for translating laboratory results into forensic practice, and to enable bloodstain age determination on the crime scene

    Compared Efficacy of Adjuvant Intravesical BCG-TICE vs. BCG-RIVM for High-Risk Non-Muscle Invasive Bladder Cancer (NMIBC): A Propensity Score Matched Analysis

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    Background: Intravesical immunotherapy with bacillus Calmette-Guerin (BCG) is the standard therapy for high-risk non-muscle invasive bladder cancer (NMIBC). The superiority of any BCG strain over another could not be demonstrated yet. Methods: Patients with NMIBCs underwent adjuvant induction ± maintenance schedule of intravesical immunotherapy with either BCG TICE or RIVM at two high-volume tertiary institutions. Only BCG-naïve patients and those treated with the same strain over the course of follow-up were included. One-to-one (1:1) propensity score matching (PSM) between the two cohorts was utilized to adjust for baseline demographic and tumor characteristics imbalances. Kaplan-Meier estimates and multivariable Cox regression models according to high-risk NMIBC prognostic factors were implemented to address survival differences between the strains. Sub-group analysis modeling of the influence of routine secondary resection (re-TUR) in the setting of the sole maintenance adjuvant schedule for the two strains was further performed. Results: 852 Ta-T1 NMIBCs (n = 719, 84.4% on TICE; n = 133, 15.6% on RIVM) with a median of 53 (24-77) months of follow-up were reviewed. After PSM, no differences at 5-years RFS, PFS, and CSS at both Kaplan-Meier and Cox regression analyses were detected for the whole cohort. In the sub-group setting of full adherence to European/American Urology Guidelines (EAU/NCCN), BCG TICE demonstrated longer 5-years RFS compared to RIVM (68% vs. 43%, p = 0.008; HR: 0.45 95% CI 0.25-0.81). Conclusion: When routinely performing re-TUR followed by a maintenance BCG schedule, TICE was superior to RIVM for RFS outcomes. However, no significant differences were detected for PFS and CSS, respectively
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