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Effect of chemical mechanical polishing on surface nature of titanium implants FT-IR and wettability data of titanium implants surface after chemical mechanical polishing implementation
No full textAbstractBioactivity of titanium depends on the quality and characteristics of its surface oxide film. Through implementation of chemical mechanical polishing (CMP) process on titanium plates, a protective oxide (titania) film grows on the titanium based implant surface. In this article, surface properties of the titanium oxide are investigated as a function of the CMP process conditions. Surface responses were evaluated in terms of wettability, nano-scale surface roughness and material removal rates (MRR). Surface chemical compositions were also evaluated through Fourier transform infrared spectroscopy (FT-IR)
Pinyon and Juniper Encroachment into Sagebrush Ecosystems Impacts Distribution and Survival of Greater Sage-Grouse
No full textAbstractIn sagebrush (Artemisia spp.) ecosystems, encroachment of pinyon (Pinus spp.) and juniper (Juniperus spp.; hereafter, “pinyon-juniper”) trees has increased dramatically since European settlement. Understanding the impacts of this encroachment on behavioral decisions, distributions, and population dynamics of greater sage-grouse (Centrocercus urophasianus) and other sagebrush obligate species could help benefit sagebrush ecosystem management actions. We employed a novel two-stage Bayesian model that linked avoidance across different levels of pinyon-juniper cover to sage-grouse survival. Our analysis relied on extensive telemetry data collected across 6 yr and seven subpopulations within the Bi-State Distinct Population Segment (DPS), on the border of Nevada and California. The first model stage indicated avoidance behavior for all canopy cover classes on average, but individual grouse exhibited a high degree of heterogeneity in avoidance behavior of the lowest cover class (e.g., scattered isolated trees). The second stage modeled survival as a function of estimated avoidance parameters and indicated increased survival rates for individuals that exhibited avoidance of the lowest cover class. A post hoc frailty analysis revealed the greatest increase in hazard (i.e., mortality risk) occurred in areas with scattered isolated trees consisting of relatively high primary plant productivity. Collectively, these results provide clear evidence that local sage-grouse distributions and demographic rates are influenced by pinyon-juniper, especially in habitats with higher primary productivity but relatively low and seemingly benign tree cover. Such areas may function as ecological traps that convey attractive resources but adversely affect population vital rates. To increase sage-grouse survival, our model predictions support reducing actual pinyon-juniper cover as low as 1.5%, which is lower than the published target of 4.0%. These results may represent effects of pinyon-juniper cover in areas with similar ecological conditions to those of the Bi-State DPS, where populations occur at relatively high elevations and pinyon-juniper is abundant and widespread
Cognitive Frailty and Adverse Health Outcomes: Findings From the Singapore Longitudinal Ageing Studies (SLAS)
No full textAbstractObjectivesThere is a recent consensus proposal of “cognitive frailty” defined by the presence of both physical frailty and cognitive impairment in the absence of dementia. The relevance, validity, and utilization of cognitive frailty, however, is presently unclear. We determine whether concurrent physical frailty and cognitive impairment, compared with physical frailty alone substantially increased adverse health outcomes (functional disability, hospitalization, poor quality of life [QOL], and mortality).DesignLongitudinal study.SettingPopulation-based cohort (Singapore Longitudinal Ageing Study, SLAS).ParticipantsTwo thousand three hundred seventy-five Chinese Singaporeans aged 55 and above without dementia and degenerative disorders.MeasurementsThe associations of physical frailty (Cardiovascular Health Study criteria: 0 = robust, 1-2 = pre-frail, 3-5 = frail) with and without cognitive impairment (mini-mental state examination <26) and adverse outcomes were estimated, controlling for age, gender, education, comorbidity, smoking, alcohol consumption, depressive symptoms, baseline activities of daily living-instrumental and basic activities of daily living disability or QOL score.ResultsCompared to robust noncognitively impaired individuals, physical pre-frailty with cognitive impairment was associated with a twofold increased prevalence and incidence of functional disability, a twofold increased incidence of poor QOL, and 1.8-fold increased mortality risks. Cognitively impaired frail individuals stood out with 12- to 13-fold increased prevalence and incidence of functional disability, a five- and 27-fold increased prevalence and incidence of low QOL, and a fivefold increased mortality risk. The estimated prevalence of physical frailty with cognitive impairment was 1.8%, and physical pre-frailty with cognitive impairment was 8.9%.ConclusionPre-frailty and frailty with impaired cognitive function, found in 10.7% of this dementia-free population, was associated with an evidently high risk of adverse health outcomes
Expression patterns of the chromosome 21 MicroRNA cluster (miR-99a, miR-125b and let-7c) in chorioamniotic membranes
No full textAbstractTrisomy 21 (T21) is the most common chromosome abnormality in humans and is associated with a spectrum of phenotypes, including cognitive impairment, congenital heart defects and immune system defects. In addition, T21 is also associated with abnormalities of fetal membranes including chorioamniotic separation, delayed fusion of the chorioamniotic membranes, defects in syncytiotrophoblast formation, as well as amniocyte senescence. There is evidence indicating miRNAs encoded by sequences on chromosome 21 (Chr-21) are involved in several of the cognitive and neurological phenotypes of T21, but the role of Chr-21 derived miRNAs in fetal membrane abnormalities associated with T21 has not been investigated. In the current study, we determined the expression patterns of three miRNAs derived from a cluster on Chr-21 – hsa-miR-99a, hsa-miR-125b and hsa-let-7c in chorioamniotic membranes obtained from term pregnancies with spontaneous rupture (n = 20). Tissue and location specific expression patterns within the chorioamniotic membranes were identified. The rupture zone in the choriodecidua had distinct expression patterns compared to other fetal membrane locations. Despite the increased gene dosage associated with T21, the expression of all three miRNAs was reduced in cultured T21 amniocytes as compared to cultured euploid amniocytes. In silico analysis of experimentally validated targets of the three miRNAs suggest these Chr-21 derived miRNAs play a potential role in fetal membrane rupture and the fetal membrane defects associated with T21
Retrograde pericatheter urethrography (RPU) technique and its clinical use after urethroplasty: A single center experience
No full textAbstractObjectiveTo describe our technique of retrograde pericatheter urethrography (RPU) and its clinical use after urethroplasty.Subjects and methodsBetween January 2008 and December 2013, 387 patients with urethral stricture underwent urethroplasty at our center. A total of 343 of these patients underwent RPU 3 weeks post-operatively. For this retrospective study their files were evaluated with regard to: demographics, duration of symptoms, site, mean length of stricture, type of surgery, RPU findings, contrast-medium related complications and need of re-intervention. The eventual surgical success was defined as asymptomatic voiding with no clinical evidence of residual stricture (good flow rate and no residual urine) until the last follow up.ResultsFollow up ranged from 8 to 41 (mean 28) months. The mean duration of symptoms was 4.8 months. The mean stricture length, as seen on radiography, was 2.1cm. 183 patients (53.3%) underwent anastomotic urethroplasty, while 160 (46.6%) underwent substitution urethroplasty. RPU showed urethral healing in 292 (85.2%) and contrast extravasation in 51 (14.8%) patients. No contrast-medium related complications were reported. Re-intervention was needed in 7.2% (21/292) of the patients who showed normal urethral healing and in 74.5% (38/51) of the patients who showed contrast extravasation on RPU. By the time of the last follow up the overall success rate was 82.7% (284/343 patients).ConclusionRPU is the most useful radiological diagnostic method for evaluating the appropriate time for catheter removal after urethroplasty. It helps to assess urethral healing and patency after urethroplasty. Prolonged catheterization in patients showing contrast extravasation may be helpful
Inelastic and quasi-elastic neutron scattering spectrometers in J-PARC
No full textAbstractJ-PARC, Japan Proton Accelerator Research Complex provides short pulse proton beam at a repetition rate 25Hz and the maximum power is expected to be 1MW. Materials and Life Science Experimental Facility (MLF) has 23 neutron beam ports and 21 instruments have already been operated or under construction/commissioning. There are 6 inelastic/quasi-elastic neutron scattering spectrometers and the complementary use of these spectrometers will open new insight for life science.This article is part of a Special Issue entitled “Science for Life” Guest Editor: Dr. Austen Angell, Dr. Salvatore Magazù and Dr. Federica Migliardo
Excess thermodynamic parameters for binary and ternary mixtures of {1-butanol (1)+cyclohexylamine (2)+n-heptane (3)} at different temperatures: A theoretical study
No full textAbstractIn this work, we used the experimental data of Kijevcanin et al. for determining the excess thermodynamic parameters such as excess thermal expansion coefficients αE, isothermal coefficient of pressure excess molar enthalpy (∂HmE/∂P)T and excess partial molar volumes V¯m,iE for the binary and ternary mixtures formed by {1-butanol+cyclohexylamine+n-heptanes} at (288.15–323.15) K. The αE values, for 1-butanol+cyclohexylamine are S-shaped and for 1-butanol+n-heptane are positive and for cyclohexylamine+n-heptane are negative over the mole fraction range. The (∂HmE/∂P)T values, for 1-butanol+cyclohexylamine are S-shaped and for binary mixture of 1-butanol+n-heptane are negative and for binary mixture of cyclohexylamine+n-heptane are positive over the mole fraction. The values of αE and (∂HmE/∂P)T are calculated by using the Flory theory, the results show a good agreement with experimental data. The values of αE and (∂HmE/∂P)T for ternary mixture {1-butanol+cyclohexylamine+n-heptanes} are determined and the experimental data are correlated as a function of the mole fraction by using the equations of Cibulka, Jasinski and Malanowski, Singe et al., Pintos et al., Calvo et al., Kohler, and Jacob–Fitzner. The results show that the Calvo et al. equation is better than others
Improving community ambulation after hip fracture: protocol for a randomised, controlled trial
No full textAbstractIntroductionAfter a hip fracture in older persons, significant disability often remains; dependency in functional activities commonly persists beyond 3 months after surgery. Endurance, dynamic balance, quadriceps strength, and function are compromised, and contribute to an inability to walk independently in the community. In the United States, people aged 65 years and older are eligible to receive Medicare funding for physiotherapy for a limited time after a hip fracture. A goal of outpatient physiotherapy is independent and safe household ambulation 2 to 3 months after surgery. Current Medicare-reimbursed post-hip-fracture rehabilitation fails to return many patients to pre-fracture levels of function. Interventions delivered in the home after usual hip fracture physiotherapy has ended could promote higher levels of functional independence in these frail and older adult patients.Primary objectiveTo evaluate the effect of a specific multi-component physiotherapy intervention (PUSH), compared with a non-specific multi-component control physiotherapy intervention (PULSE), on the ability to ambulate independently in the community 16 weeks after randomisation.DesignParallel, two-group randomised multicentre trial of 210 older adults with a hip fracture assessed at baseline and 16 weeks after randomisation, and at 40 weeks after randomisation for a subset of approximately 150 participants.Participants and settingA total of 210 hip fracture patients are being enrolled at three clinical sites and randomised up to 26 weeks after admission. Study inclusion criteria are: closed, non-pathologic, minimal trauma hip fracture with surgical fixation; aged ≥ 60 years at the time of randomisation; community residing at the time of fracture and randomisation; ambulating without human assistance 2 months prior to fracture; and being unable to walk at least 300 m in 6minutes at baseline. Participants are ineligible if the interventions are deemed to be unsafe or unfeasible, or if the participant has low potential to benefit from the interventions.InterventionsParticipants are randomly assigned to one of two multi-component treatment groups: PUSH or PULSE. PUSH is based on aerobic conditioning, specificity of training, and muscle overload, while PULSE includes transcutaneous electrical nerve stimulation, flexibility activities, and active range of motion exercises. Participants in both groups receive 32 visits in their place of residence from a study physiotherapist (two visits per week on non-consecutive days for 16 weeks). The physiotherapists’ adherence to the treatment protocol, and the participants’ receipt of the prescribed activities are assessed. Participants also receive counselling from a registered dietician and vitamin D, calcium and multivitamin supplements during the 16-week intervention period.MeasurementsThe primary outcome (community ambulation) is the ability to walk 300 m or more in 6minutes, as assessed by the 6-minute walk test, at 16 weeks after randomisation. Other measures at 16 and 40 weeks include cost-effectiveness, endurance, dynamic balance, walking speed, quadriceps strength, lower extremity function, activities of daily living, balance confidence, quality of life, physical activity, depressive symptoms, increase of ≥ 50 m in distance walked in 6minutes, cognitive status, and nutritional status.AnalysisAnalyses for all aims will be performed according to the intention-to-treat paradigm. Except for testing of the primary hypothesis, all statistical tests will be two-sided and not adjusted for multiple comparisons. The test of the primary hypothesis (comparing groups on the proportion who are community ambulators at 16 weeks after randomisation) will be based on a one-sided 0.025-level hypothesis test using a procedure consisting of four interim analyses and one final analysis with critical values chosen by a Hwang-Shih-Decani alpha-spending function. Analyses will be performed to test group differences on other outcome measures and to examine the differential impact of PUSH relative to PULSE in subgroups defined by pre-selected participant characteristics. Generalised estimating equations will be used to explore possible delayed or sustained effects in a subset of participants by comparing the difference between PUSH and PULSE in the proportion of community ambulators at 16 weeks with the difference at 40 weeks.DiscussionThis multicentre randomised study will be the first to test whether a home-based multi-component physiotherapy intervention targeting specific precursors of community ambulation (PUSH) is more likely to lead to community ambulation than a home-based non-specific multi-component physiotherapy intervention (PULSE) in older adults after hip fracture. The study will also estimate the potential economic value of the interventions
Glass compositions and tempo of post-17 ka eruptions from the Afar Triangle recorded in sediments from lakes Ashenge and Hayk, Ethiopia
No full textAbstractNumerous volcanoes in the Afar Triangle and adjacent Ethiopian Rift Valley have erupted during the Quaternary, depositing volcanic ash (tephra) horizons that have provided crucial chronology for archaeological sites in eastern Africa. However, late Pleistocene and Holocene tephras have hitherto been largely unstudied and the more recent volcanic history of Ethiopia remains poorly constrained. Here, we use sediments from lakes Ashenge and Hayk (Ethiopian Highlands) to construct the first <17 cal ka BP tephrostratigraphy for the Afar Triangle. The tephra record reveals 21 visible and crypto-tephra layers, and our new database of major and trace element glass compositions will aid the future identification of these tephra layers from proximal to distal locations. Tephra compositions include comendites, pantellerites and minor peraluminous and metaluminous rhyolites. Variable and distinct glass compositions of the tephra layers indicate they may have been erupted from as many as seven volcanoes, most likely located in the Afar Triangle. Between 15.3−1.6 cal. ka BP, explosive eruptions occurred at a return period of <1000 years. The majority of tephras are dated at 7.5−1.6 cal. ka BP, possibly reflecting a peak in regional volcanic activity. These findings demonstrate the potential and necessity for further study to construct a comprehensive tephra framework. Such tephrostratigraphic work will support the understanding of volcanic hazards in this rapidly developing region
Dataset of total, oligomeric alpha-synuclein and hemoglobin levels in plasma in Parkinson׳s disease
No full textAbstractThis data article presents a dataset of total, oligomeric alpha-synuclein and hemoglobin levels in plasma of drug-naïve PD patients and controls. This is the first attempt to assess the effect of hemolysis rate on oligomeric alpha-synuclein levels in peripheral plasma. The data are associated with the research article “Oligomeric alpha-synuclein and glucocerebrosidase activity levels in GBA-associated Parkinson׳s disease” (Pchelina et al., 2016) [1]