AbstractThe complex structure and mechanics of elastoplastic functionally graded materials (FGM) is studied from the standpoint of fractal geometry. First, upon introducing the fineness as the number of grains of either phase across the FGM, the two-phase FGM is characterized using fractals, and an interfacial fractal dimension is estimated for varying degrees of fineness. A variation in local fractal dimension is considered across or along the FGM domain, and it is characterized by Fourier series and Beta function fits. Assuming the FGM is made of locally isotropic Titanium (Ti) and Titanium Monoboride (TiB), pure shear tests are simulated using ABAQUS for fineness levels of 50, 100, and 200 under the uniform kinematic boundary condition (UKBC) and the uniform static boundary condition (USBC). The material response observed under these BCs shows high sensitivity of these systems to loading conditions. Furthermore, plastic evolution of Ti grains, assuming isotropic plastic hardening, displays a fractal, p...

Functional connectivity between brain regions during swallowing tasks is still not well understood. Understanding these complex interactions is of great interest from both a scientific and a clinical perspective. In this study, functional magnetic resonance imaging (fMRI) was utilized to study brain functional networks during voluntary saliva swallowing in twenty-two adult healthy subjects (all females, years of age). To construct these functional connections, we computed mean partial correlation matrices over ninety brain regions for each participant. Two regions were determined to be functionally connected if their correlation was above a certain threshold. These correlation matrices were then analyzed using graph-theoretical approaches. In particular, we considered several network measures for the whole brain and for swallowing-related brain regions. The results have shown that significant pairwise functional connections were, mostly, either local and intra-hemispheric or symmetrically inter-hemispheric. Furthermore, we showed that all human brain functional network, although varying in some degree, had typical small-world properties as compared to regular networks and random networks. These properties allow information transfer within the network at a relatively high efficiency. Swallowing-related brain regions also had higher values for some of the network measures in comparison to when these measures were calculated for the whole brain. The current results warrant further investigation of graph-theoretical approaches as a potential tool for understanding the neural basis of dysphagia.

The case of a turbulent round jet impinging perpendicularly onto a rotating, heated disc is investigated, aiming at understanding the mechanisms at the origin of the influence of rotation on the radial wall jet and associated heat transfer. The present study is based on the complementary use of an analysis of the order of magnitudes of the terms of the mean momentum and Reynolds stress transport equations, available experiments and dedicated Reynolds-Averaged Navier–Stokes (RANS) computations with refined turbulence models. The analysis identifies a scenario for the appearance of rotational effects when the rotation rate is gradually increased.

Since their discovery in the late 1940s, the Dead Sea Scrolls, some 900 ancient Jewish texts, have never stopped attracting the attention of scholars and the broad public alike, because they were created towards the end of the Second Temple period and the "time of Christ". Most of the work on them has been dedicated to the information contained in the scrolls' text, leaving physical aspects of the writing materials unexamined. They are, however, crucial for both historical insight and preservation of the scrolls. Although scientific analysis requires handling, it is essential to establish the state of degradation of these valued documents. Polarized Raman Spectroscopy (PRS) is a powerful tool for obtaining information on both the composition and the level of disorder of molecular units. In this study, we developed a non-invasive and non-destructive methodology that allows a quantification of the disorder (that can be related to the degradation) of protein molecular units in collagen fibers. Not restricted to collagen, this method can be applied also to other protein-based fibrous materials such as ancient silk, wool or hair. We used PRS to quantify the degradation of the collagen fibers in a number of fragments of the Temple Scroll (11Q19a). We found that collagen fibers degrade heterogeneously, with the ones on the surface more degraded than those in the core.

High power light emitting diodes (HP LED) are energy efficient light sources that have been developing at great speed. Aging process was performed at increased pin temperatures, with approximate values of 80°C, 90°C and 100°C and constant current. The conditions in chambers are simultaneously monitored for approximately 5000 hours. The change in HP LED's SPD was small and for the second test group was within the narrower wavelength interval than for the first. This interval corresponds to the phosphor emission region and indicates that important factor of white LED's SPD stability is the choice of type of phosphor used.

Background: The atypical chemokine receptor CXCR7 is highly expressed in various types of cancer. Results: CXCR7 Nanobodies were generated and show inhibition of β-arrestin2 signaling and secretion of angiogenic CXCL1 in vitro. Anti-CXCR7 Nanobodies reduce tumor growth by inhibiting angiogenesis. Conclusion: CXCR7 inhibition by Nanobodies inhibit head and neck tumor formation. Significance: Anti-CXCR7 therapies are potential novel treatments against head and neck cancer. The chemokine receptor CXCR7, belonging to the membrane-bound G protein-coupled receptor superfamily, is expressed in several tumor types. Inhibition of CXCR7 with either small molecules or small interference (si)RNA has shown promising therapeutic benefits in several tumor models. With the increased interest and effectiveness of biologicals inhibiting membrane-bound receptors we made use of the “Nanobody platform” to target CXCR7. Previously we showed that Nanobodies, i.e. immunoglobulin single variable domains derived from naturally occurring heavy chain-only camelids antibodies, represent new biological tools to efficiently tackle difficult drug targets such as G protein-coupled receptors. In this study we developed and characterized highly selective and potent Nanobodies against CXCR7. Interestingly, the CXCR7-targeting Nanobodies displayed antagonistic properties in contrast with previously reported CXCR7-targeting agents. Several high affinity CXCR7-specific Nanobodies potently inhibited CXCL12-induced β-arrestin2 recruitment in vitro. A wide variety of tumor biopsies was profiled, showing for the first time high expression of CXCR7 in head and neck cancer. Using a patient-derived CXCR7-expressing head and neck cancer xenograft model in nude mice, tumor growth was inhibited by CXCR7-targeting Nanobody therapy. Mechanistically, CXCR7-targeting Nanobodies did not inhibit cell cycle progression but instead reduced secretion of the angiogenic chemokine CXCL1 from head and neck cancer cells in vitro, thus acting here as inverse agonists, and subsequent angiogenesis in vivo. Hence, with this novel class of CXCR7 inhibitors, we further substantiate the therapeutic relevance of targeting CXCR7 in head and neck cancer.

Urinary tract infections are common bacterial diseases and also a frequent reason for prescribing antibiotics. Knowledge about the type of pathogens and their resistance patterns may help the clinician to choose the correct treatment. In this study, the prevalence and the resistance pattern of the main bacteria responsible for urinary tract infections оf hospitalized patients in Clinical centar Kragujevac was evaluated throughout a tree-year period. Cross-sectional study in the hospital settings was conducted and urine samples were collected from 662 patients with urinary tract infections and tested using standard procedures. The disk-diffusion method on Mueller-Hinton agar according to Clinical and Laboratory Standards Institute guidelines (CLSI) was performed for assessment of antimicrobial susceptibility. The most frequently isolated pathogen were Klebsiella spp. (219 isolates, i.e. 33,1%), Proteus mirabilis (107 isolates, i.e. 16,2%), Enterobacter (86 isolates, i.e. 13%), Escherichia coli (82 isolates, i.e. 12,4%), Pseudomonas aeruginosa (70 isolates, i.e. 10,6%), Enterococcus spp (39 isolates, i.e. 5,9% ) and Proteus vulgaris (38 isolates, i.e. 5,7%). Group of patients older than 65 years was the largest one 426 (64,4%). Gram negative bacteria showed the highest degree of resistance (92.3% - 100%) to penicillins (ampicillin, amoxicillin, amoxicillin + clavulanic acid) and third-generation cephalosporins (cefotaxime, ceftriaxone and ceftazidime) (88.3% - 98, 4%), while Gram positive Enterococcus spp showed the highest degree of resistance to aminoglycosides (gentamicin and amikacin) (96.8% - 100%) and fluoroquinolone ciprofliksacin (100%). The lowest resistance rate of the studied Gram negative pathogens was to carbapenems (imipenem and meropenem) and piperacillin / tazobactam (6.9% - 35.5%), while the lowest level of resistance of gram positive Enterococcus spp was found to glycopeptide antibiotics (vancomycin and teicoplanin) (3.0% - 3.3%). When choosing antibiotics, the pharmacokinetics and pharmacodynamics, renal and liver function, adverse reactions with other drugs, as well as the results of susceptibility testing should be taken into consideration. According to our data, empiric treatment for Klebsiella spp, Proteus mirabilis, Enterobacter, Escherichia coli, Pseudomonas aeruginosa and Proteus vulgaris should include carbapenems or piperacillin / tazobactam, and when it comes to Enterococcus spp , glycopeptide antibiotics are appropriate choice.