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Even if soft tissue adhesion on titanium surfaces is an issue of great interest for transmucosal dental implants and percutaneous devices, few specific surface modification strategies ...have been approached so far to face it. Topographical surface modification is an interesting strategy because quality of soft tissues can be effectively improved by contact guidance effect on fibroblasts. Conversely, biofilm formation is encouraged in presence of rough or porous surfaces, as well as of surface patterns, if the roughness overcome the threshold of 0.2 μm. This issue becomes particularly critical in medical devices which cross different biological tissues and, through soft tissues, establish a direct contact with the external environment. In the present research, three different grooved patterns (5, 10 and 30 μm wide) were produced on commercially pure titanium by means of Electron Beam (EB) structuring maintaining the average surface roughness lower than 0.2 μm. The EB surface structured samples were characterized by means of optical and atomic force microscopy, contact and non-contact profilometry, X-Ray Diffraction, residual stress measurements as well as bacteria and cell adhesion tests. The 10 μm wide grooves resulted able to support fibroblast alignment onto the metallic substrate. Unexpectedly, all the EB surface structured surfaces not only did not enhance, but even reduced bacterial adhesion up to 48 h culture.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
It is shown that the frequency dependence of the phenomenological parameters entering Langmuir kinetic equation describing the surface adsorption could be related to a random distribution of ...relaxation times. A theoretical model based on a generalization of Langmuir isotherm, taking into account a homogeneous distribution of relaxation times is proposed for supercapacitor modeling. Its theoretical predictions agree well with experimental data derived by the analysis of Lissajous figures describing the response of an electrochemical cell excited with a well defined frequency. According to our data, the effective desorption time is a rapidly decreasing function of the frequency of the applied signal, whereas the effective adsorption coefficient is an increasing function of it. The effective relaxation time is independent of the ionic concentration, whereas the effective adsorption coefficient strongly depends on this quantity. A large increase in the adsorption coefficient is reported, for the electrochemical cells with high surface area of the electrodes.
•Evidence of frequency dependence of the parameters entering Langmuir kinetic equation describing surface adsorption.•The desorption time is a decreasing function of the frequency, the adsorption coefficient is an increasing function of it.•Generalization of the theory for linear systems, with a response function given by a distribution of relaxation times.•Modeling the supercapacitor response to an harmonic excitation of small amplitude, where the electrodes are blocking.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Background
Giardia duodenalis is a parasite of several mammalian species, including humans, distributed worldwide. This research aimed to identify the molecular assemblages/sub-assemblages of G. ...duodenalis and to determine the intra-assemblage genetic variation of the different genes of assemblages A and B in pre-school children in the cities of Araguari and Uberlândia, Minas Gerais, Brazil.
Methods
The molecular characterization followed β-giardin (bg), glutamate dehydrogenase (gdh) and triose phosphate isomerase (tpi) protocols.
Results
Of 226 stool samples, G. duodenalis cysts were found in 45 (19.9%). The tpi gene was amplified in 34 samples: 16 assemblage A, 14 B and four mixed samples A/B. The gdh gene was amplified in 32 samples, including 14 A, 16 B and two A/B. For the bg gene, 19 samples were sequenced: nine assemblage A, five B, three E, and two mixed, A/E and B/E. Animal-specific assemblage E were identified by bg, but were not confirmed for other genes. Twelve samples were characterized by full agreement of the three genes. Two new multilocus genotyping (MLGs) for assemblage A and two new MLGs for assemblage B were also described.
Conclusions
These findings substantiate the importance of using more than one gene protocol since the sensitivity and genetic variability changes with the locus used.
Access numbers: The GenBank access numbers for the nucleotide sequences reported in this article are: JQ794877–JQ794890, JX033113–JX033118
We derive a continuum theory for a thermoviscoelastic composite with the help of an entropy production inequality proposed by Green and Laws. The composite is modelled as a mixture of an elastic ...solid and a Kelvin-Voigt material. The theory is derived in lagrangian description. It is shown that the linear heat conduction tensor is symmetric and that the theory allows for "second sound" effects. In contrast with other theories of solid-fluid mixtures, in the present theory the diffusive force depends on both relative displacement and relative velocity. A uniqueness result in the linearized theory is presented. Finally, the effect of a concentrated heat source is investigated.
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BFBNIB, DOBA, GIS, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
We evaluated a multi-family support group intervention program in elementary schools. Kindergarten through third-grade children at eight urban schools in a Midwestern university community were ...universally invited to participate in the Families and Schools Together (FAST) program, and made up half of the study participants; the other half were K-3 children identified by teachers as having behavioral problems and being at risk for referral to special education services. Children were initially paired on the basis of five relevant matching variables, including teacher assessment of behavioral problems, and then randomly assigned to either ongoing school services (control) or the FAST program. Parents and teachers completed pre-, post-, and 1-year follow-up assessments. Data were available and analyzed for 67 pairs. Immediate follow-up parent reports showed that FAST students declined less on a family adaptability measure relative to control group students. This effect was still present at the 1-year follow-up assessment. In addition, FAST parents reported statistically significant reductions in children's externalizing (aggressive) behaviors, as compared to the reports of control group parents. School district data showed descriptively fewer special-education referrals for FAST children (one case) as compared with control group children (four cases). Results are discussed in relation to future research on universal prevention programs.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Giardia duodenalis (syn. Giardia intestinalis and Giardia lamblia) is a widespread intestinal parasite in mammals, including humans and pets worldwide. It should be considered a species complex and ...comprises eight assemblage (A–H). This works aimed to determine the genotypic variability among G. duodenalis isolates from dogs from Minas Gerais state, Brazil. Fecal samples of 97 dogs, from 1-to-10 months old from 15 commercial kennels, were collected and analyzed by the zinc sulfate centrifugal flotation technique, to determine their positivity for G. duodenalis cysts. Cysts pellets were stored and submitted to PCR and nested-PCR reactions with gdh and tpi primers, and then sequencing. Among positive samples (n = 19), fragment amplifications of gdh and tpi genes was observed in 16 (84,2%) and 14 (73,6%), respectively. In total, 30 sequences were obtained. Sequencing analysis showed that for gdh, all isolates were identified as host-specific genotype D, and for tpi, besides host-specific genotype C, were also observed zoonotic genotypes A and B. This study provides, for the first time, current information about genetic characterization of G. duodenalis isolates found in dogs in Minas Gerais state.
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•Dogs have been considered as potential reservoirs of Giardia duodenalis.•Sequencing of gdh characterized all isolates as host-specific D assemblage.•Sequencing of tpi characterized isolates as host-specific and zoonotic assemblages.•Combine generic and specific primers seems to be the ideal for genotyping dog isolates.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
The plane dynamic contact problem of the harmonic oscillations of a rigid punch on the free surface of an elastic layer of porous isotropic material with linear properties is considered. The Fourier ...transformation of the problem is reduced to a Fredholm integral equation of the first kind in the contact pressure. The properties of the kernel of the fundamental integral equation are investigated and a numerical method of solving it is constructed. Numerical results are compared with existing results in classical limiting cases.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
This paper is concerned with the linear theory of composites modelled as mixtures of two Cosserat elastic continua. First, we present a minimum principle in the case of equilibrium. Then, we consider ...the dynamic theory and establish a minimum principle of Reiss type for a mixed problem.
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FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
Abstract
Pulse wave velocity (PWV) is an independent cardiovascular risk factor (CVRF), and there are multiple ways to measure it with more or less accuracy.
We sought to easily develop an invasive ...gold standard axial PWV during cardiac catheterization between ascending aorta (AAo) and tibial artery (TIB) or humeral artery (HUM). Aorto-humeral PWV is not a usual measurement site because of its difficulty to estimate it non-invasively. Axial PWV demonstrates a greater correlation with CVRF, with carotid-femoral PWV the common way to estimate it non-invasively in hypertensive patients and others.
Methods
26 patients were enrolled for AAo-TIB PWV measurements and 50 for AAo-HUM. A cuff connected to the hemodynamic Phillips workstation of the cathlab was placed around the right leg, at mid-calf, and was inflated to superimpose TIB pulsatile blood pressure waves on AAo blood pressure recorded with a fluid filled diagnostic 5 Fr or interventional 6 Fr catheter left at the end of the diagnostic coronary angiography in the ascending aorta. The distance between AAo and TIB was estimated by the distance between axillary and iliac crest, added with the distance between iliac crest and mid-calf. PWV was then calculated from the length estimated between AAo and mid-calf, and the time delay between AAo and TIB pulses (see figure) by gating to the R-wave of the ECG (upper trace) for both measurements, using a dedicated software written in MatLab®. For AAo=HUM PWV, in 50 patients the pressure of the catheter was sequencially recorded in the AoAsc then pulled back in the humeral artery. Both recordings were matched off-line based on the R top of the ECG recorded and the delay between the rise of the 2 pressure curves in the same MatLab® software.
Results
Mean age of our patients is 62,7±9,2 years. 82% had chronic hypertension and 33% had diabetes mellitus. 4 patients (15%) had clinical peripheral artery disease and only one had a stenting on femoral artery. No patients had previous vascular bypass.
Aorto-tibial PWV showed an average PWV at 8.4±1.4 m/s. Aorto-humeral PWV showed an average PWV at 7.2±1.8 m/s. The PWV tended to be 0,6 m/s lower in patients with ≤2 cardiovascular risk factors versus >3.
Conclusion
We describe a simple and accurate PWV gold standard that can be recorded in any patient admitted for a coronary angiography. Aorto-tibial PWV is easier to obtain. Adding this parameter in the global assessment of patients with hypertension or other CVD will refine their CVRF profile.
Funding Acknowledgement
Type of funding sources: None.
Giardia duodenalis is a small intestinal protozoan parasite of several terrestrial vertebrates. This work aims to assess the genotypic variability of Giardia duodenalis isolates from cattle, sheep ...and pigs in the Southeast of Brazil, by comparing the standard characterization between glutamate dehydrogenase (gdh) and triose phosphate isomerase (tpi) primers. Fecal samples from the three groups of animals were analyzed using the zinc sulphate centrifugal flotation technique. Out of 59 positive samples, 30 were from cattle, 26 from sheep and 3 from pigs. Cyst pellets were stored and submitted to PCR and nested-PCR reactions with gdh and tpi primers. Fragment amplification of gdh and tpi genes was observed in 25 (42.4%) and 36 (61.0%) samples, respectively. Regarding the sequencing, 24 sequences were obtained with gdh and 20 with tpi. For both genes, there was a prevalence of E specific species assemblage, although some isolates have been identified as A and B, by the tpi sequencing. This has also shown a larger number of heterogeneous sequences, which have been attribute to mixed infections between assemblages B and E. The largest variability of inter-assemblage associated to the frequency of heterogeneity provided by tpi sequencing reinforces the polymorphic nature of this gene and makes it an excellent target for studies on molecular epidemiology.
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DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK, VSZLJ
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