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At low temperatures, classical ultrasoft particle systems develop interesting phases via the self-assembly of particle clusters. In this study, we reach analytical expressions for the energy and the density interval of the coexistence regions for general ultrasoft pairwise potentials at zero temperatures. We use an expansion in the inverse of the number of particles per cluster for an accurate determination of the different quantities of interest. Differently from previous works, we study the ground state of such models, in two and three dimensions, considering an integer cluster occupancy number. The resulting expressions were successfully tested in the small and large density regimes for the Generalized Exponential Model α, varying the value of the exponent.

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The aim of this article is to construct spatial models for the activation of sweat glands for healthy subjects and subjects suffering from peripheral neuropathy by using videos of sweating recorded from the subjects. The sweat patterns are regarded as realizations of spatial point processes and two point process models for the sweat gland activation and two methods for inference are proposed. Several image analysis steps are needed to extract the point patterns from the videos and some incorrectly identified sweat gland locations may be present in the data. To take into account the errors, we either include an error term in the point process model or use an estimation procedure that is robust with respect to the errors.

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AIM: The carrier-based obturation is a reliable technique for sealing the endodontic space. The GuttaCore with a pink internal core of cross-linked gutta-percha, named GuttaCore Pink, has been recently introduced into the market. The aim of this in vitro study was to compare the quality of the apical seal of two-carrier-based system, Soft Core and the GuttaCore Pink, through the measurement of apical dye leakage. MATERIALS AND METHODS: Eighty-six extracted human teeth with single canals were used. Samples were shaped using ProTaper Universal rotary files up to a #30 apical size and randomly divided into four groups. Group SC (n = 40) was obturated with #30 Soft Core Obturators; Group GCP (n = 40) was obturated with #30 GuttaCore Pink obturators; Group CT+ (n = 3) and CT- (n = 3) left nonobturated used as positive and negative controls, respectively. The samples underwent a process of passive/active dye penetration and after a clearing procedure. The extent of the dye was measured under stereomicroscope. RESULTS: The Mann-Whitney U test showed a statistically significant difference (p <0.05) between Soft Core and GuttaCore Pink in terms of apical dye leakage, both considering the mean and the maximum infiltration value with a greater infiltration rate for Soft Core. CONCLUSION: In vitro GuttaCore Pink showed less apical dye leakage than Soft Core. CLINICAL SIGNIFICANCE: The apical leakage of carrier-based obturation materials, observed in both GuttaCore Pink and Soft Core, may be considered material-dependent.

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The umbrella sampling (US) approach has been demonstrated to be a very efficient method for estimating the ligand-binding affinity. However, most of the calculated values overestimate experimental ones that are probably caused by the inaccurate representation of the interaction between the ligand and the surrounding molecules. The issue can be resolved via the implementation aspects of λ-alteration simulation into the US approach, which we call the λ-dependent umbrella sampling (λUS) scheme. In particular, the electrostatic and van der Waals interactions were simultaneously changed by using the coupling parameter λ during λUS simulations. The mean value of obtained results, ∆GUSλ=0.20=-11.59±1.51 kcal mol-1 , is in good fitting to the mean value of respective experiments, ∆GEXP = - 11.26 ± 0.89 kcal mol-1 . Moreover, the correlation between the proposed approach and experiment is quite good with a value of RUSλ=0.20=0.82±0.10 . The λUS scheme significantly enhances the calculated accuracy since the RMSE of the proposed scheme is smaller than traditional US simulations, RMSEUSλ=0.20=2.99±0.82 kcal mol-1 versus RMSEUSλ=0.00=5.48±0.81 kcal mol-1 . Furthermore, the precision is increased since the computed error via λUS approach, δUSλ=0.20=1.51 kcal mol-1 , was smaller than those of the US simulation, δUSλ=0.00=1.78 kcal mol-1 . Overall, the proposed approach perhaps provides an efficient way to accurately and precisely estimate the ligand-binding free energy.

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Liquid-crystal polymers (LCPs) are well known materials for functional sensor and actuators, because of their high-responsiveness to an electric field. Owing to their complex physical nature, however, the prediction of the functions of LCPs is a challenge. To attack this problem from a molecular point of view, a simulation study is a promising approach. In this work, for future applications of molecular dynamics simulations to problems involving an electric field, we develop an LCP model which consists of coarse-grained mesogenic molecules and smeared charges. For the smearing function of the electrostatic force, the Gauss error function is introduced. This smearing is optimized to attain a reasonable accuracy for phase transition phenomena of liquid crystal while numerical instabilities arising from the singularity of the Coulomb potential are circumvented. For swelling systems, our LCP model exhibits the characteristics of both liquid crystals and unentangled polymer chains; orientational order of the mesogenic units and Rouse-like relaxation dynamics. Our coarse-grained LCP model successfully incorporates electric charges and dipoles and is therefore applicable to problems concerning an electric field.

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The phase behavior of the continuous shouldered well model fluid proposed by Franzese [J. Mol. Liq. 136 (2007) 267] was examined using the Monte Carlo computer simulations in the grand canonical ensemble. The essential parts of the vapour-liquid and liquid-liquid coexistence envelopes were obtained. The Widom lines departing from coexistence envelopes were calculated using maxima of the fluctuations of the number of particles as a function of chemical potential along various isotherms. The region embracing anomalies in the properties of the model was located using the approximate criterion that involves the excess pair entropy.. The temperature of maximum density line was built by performing canonical Monte Carlo simulations. Our results are consistent with previous results from molecular dynamics constant pressure-constant temperature simulations and provide wider insight into the phase behavior of the model by using the chemical potential as the external parameter.

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AIM:To investigate the effect and safety of modified small incision cataract surgery in patients with soft core cataract.METHODS: Totally 80 cases (109 eyes) of soft cataract patients who underwent surgical treatment from January 2015 to May 2016 in ophthalmology center of our hospital, using random number table method were divided into improved group (improved manipulation of small incision cataract surgery), traditional group (traditional approach to small incision cataract surgery), 40 cases in each group.Comparison of the two groups of treatment, the incidence of complications were taken.RESULTS: There were no significant differences on uncorrected visual acuity between the two groups before and at 1d, 1wk and 1mo after operations (P>0.05).The uncorrected visual acuity of the two groups improved significantly at 1d, 1wk and 1mo after operations compared with those before operations (P0.05).The IOP of the two groups increased significantly at 1d, 1wk and 1mo after operations compared with those before operations (P<0.05).The complication rate was 9% (5/54) in the modified group, significantly lower than that in the conventional group 25% (14/55) (P<0.05).CONCLUSION: Improved small incision cataract surgery for soft cataract patients was with reliable results, less complications.

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AIM: The goal of the study was to compare the ability of two different carrier based obturation (CBO) techniques to reach working length and fill in three-dimensions root canal systems, by using CBCT. MATERIALS AND METHODS: Twenty-six extracted molars were scanned with CBCT and 40 curved canals were selected (between 30° and 90°) and divided in two similar groups (n=20). All canals were prepared up to size 25 taper .06 using nickel-titanium instrumentation. The canals in the Group SC were obturated using Soft-Core obturators (Kerr, Romulus, Mi, USA), while Group TH canals (n= 20) were obturated using Thermafil Endodontic Obturators (Tulsa Dental Products, Tulsa, OK, USA), strictly following manufacturers' instructions for use. The obturations were analyzed by means of CBCT to measure the distance from the apical limit of obturation to the apical foramen and the presence of voids inside root canals. RESULTS: There was no significant difference between the two groups in the mean distance of the apical extent of the obturation (t test, p>0.05). Overfilling occurred in only 3 cases (2 in Group TH and 1 in Group SC). The percentages of voids in both groups were very low with no significant difference (Z test, p>0.05). CONCLUSIONS: The two tested CBO techniques showed similar positive results in terms of performance, even if, after checking with verifiers, in most cases the size of the selected Soft-Core obturator was one size smaller than Thermafil.

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The genus Geobacillus is comprised of a diverse group of spore-forming Gram-positive thermophilic bacterial species and is well known for both its ecological diversity and as a source of novel thermostable enzymes. Although the mechanisms underlying the thermophilicity of the organism and the thermostability of its macromolecules are reasonably well understood, relatively little is known of the evolutionary mechanisms, which underlie the structural and functional properties of members of this genus. In this study, we have compared 29 Geobacillus genomes, with a specific focus on the elements, which comprise the conserved core and flexible genomes. Based on comparisons of conserved core and flexible genomes, we present evidence of habitat delineation with specific Geobacillus genomes linked to specific niches. Our analysis revealed that Geobacillus and Anoxybacillus share a high proportion of genes. Moreover, the results strongly suggest that horizontal gene transfer is a major factor deriving the evolution of Geobacillus from Bacillus, with genetic contributions from other phylogenetically distant taxa.

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Navigation algorithms integrating measurements from multi-sensor systems overcome the problems that arise from using GPS navigation systems in standalone mode. Algorithms which integrate the data from 2D low-cost reduced inertial sensor system (RISS), consisting of a gyroscope and an odometer or wheel encoders, along with a GPS receiver via a Kalman filter has proved to be worthy in providing a consistent and more reliable navigation solution compared to standalone GPS receivers. It has been also shown to be beneficial, especially in GPS-denied environments such as urban canyons and tunnels. The main objective of this paper is to narrow the idea-to-implementation gap that follows the algorithm development by realizing a low-cost real-time embedded navigation system capable of computing the data-fused positioning solution. The role of the developed system is to synchronize the measurements from the three sensors, relative to the pulse per second signal generated from the GPS, after which the navigation algorithm is applied to the synchronized measurements to compute the navigation solution in real-time. Employing a customizable soft-core processor on an FPGA in the kernel of the navigation system, provided the flexibility for communicating with the various sensors and the computation capability required by the Kalman filter integration algorithm.

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