Lithography-based ceramics manufacturing (LCM) processes enable the sophisticated 3 dimensional (3D) shaping of ceramics by additive manufacturing (AM). The build-up occurs, like many other AM processes, layer by layer, and is initiated by light. The built-in digital mirror device (DMD) enables the specific exposure of desired pixels for every layer, giving as a consequence a first estimation of the printing resolution in the x and y axes. In this work, a commercial zirconia slurry and the CeraFab 7500, both from Lithoz GmbH (Vienna, Austria), were used to investigate the potential of reaching this resolution. The results showed that the precision of a part is strongly dependent on the applied exposure energy. Higher exposure energies resulted in oversized dimensions of a part, whereas too low energy was not able to guarantee the formation of a stable part. Furthermore, the investigation of the layer thickness showed that the applied exposure energy (mJ/cm2) was acting in a volume, and the impact is visible in x, y, and z dimensions. The lowest applied exposure energy was 83 mJ/cm2 and showed the most accurate results for a layer thickness of 25 μm. With this energy, holes and gaps smaller than 500 μm could be printed; however, the measurements differed significantly from the dimensions defined in the design. Holes and gaps larger than 500 μm showed deviations smaller than 50 μm from the design and could be printed reliably. The thinnest printable gaps were between 100 and 200 μm. Concerning the wall thickness, the experiments were conducted to a height of 1 cm. Taking into account the stability and deformation of the walls as well, the best results after sintering were achieved with thicknesses of 200–300 μm.

Objectives This study assessed behavioral and physiologic stress parameters in cats placed in two environments: home and the veterinary hospital. With a widely used scale, several parameters were assessed, including respiratory rate (RR), heart rate (HR), systolic blood pressure (SBP), vagosympathetic responses using calculated intervals (heart rate variability [HRV]10, HRV20 and vasovagal tonus index [VVTI]) and 'stress attitude', such as struggling, vocalization and agitation during handling. In addition, we evaluated whether a feline facial pheromone analogue (FFPA) had an effect on any of these measures in either environment. Methods Using a placebo and a pheromone substance, we evaluated 30 adult and healthy cats at home and in veterinary hospitals. Statistical analyses were performed using the Shapiro-Wilk, Kruskal-Wallis, and Dunn or ANOVA and Tukey tests, as well as Spearman's correlation ( P <0.05). Results We found that exposure to FFPA did not reduce the effects of stress. Some parameters presented differences with regard to environment: the RR was 45 and 70 breaths/min and stress attitude score was 1.3 and 0.0 for cats evaluated at home and at the hospital, respectively. The HR and two vagosympathetic responses were also different between the two environments, with a HR of 160 and 187 beats/min, HRV10 of 14.24 and 14.00, and HRV20 of 14.89 and 14.65 in cats at home and the hospital, respectively. There was no variation in SBP and VVTI parameters between the environments. Conclusions and relevance Exposure to FFPA does not reduce the physiologic and behavioral changes measured in this study. Furthermore, environmental change, physical restraint and manipulation during the physical examination alter RR, HR, HRV and behavior but not SBP and VVTI. This study is relevant because physiologic and behavioral stress can affect the quality and interpretation of physical examination results. This study presents detailed data that show the effects of environment and manipulation on such parameters. Furthermore, this study shows a lack of effect of FFPA on any of these parameters.

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The aims of this study were to evaluate effects of a 6 week resistance training on electrocardiographic (ECG) and blood parameters of police dogs. Our hypothesis was that this training protocol improves fitness, contributing to the welfare of these animals. Nine dogs, 18.56±0.53 months old, were evaluated before (M1) and six weeks after (M2) a training protocol using treadmill. Their training program was performed 2 times/week, and included 20 min of treadmill activity on a speed compatible with 60-80% of HRmax on weeks 1 and 2, same exercise of weeks 1 and 2 with a 5% grade added between 7.5 and 12.5 min in weeks 3 and 4, and, finally, same exercise of weeks 3 and 4 with three short bursts of strenuous exercise, 60 min after the end of treadmill activity. On both moments, animals were examined before (T0) and after (T1) an incremental effort test, and at 30 (T2) and 120 min (T3) of recovery, measuring heart rate, respiratory rate and body temperature. Blood samples were taken to determine erythrogram, aspartate aminotransferase, creatine kinase, triglycerides, lactate and glucose. Electrocardiographic variables were analysed at T0 and T1. All variables were analysed by one-way ANOVA and Tukey tests, with P≤0.05. After training, there was an increase on the length of work on treadmill of 41.5% for the German Shepherd (P=0.0139) and 21.4% for the Belgian Malinois (P=0.0085) along with a increase of maximal speed of 34.0% for the German Shepherd (P=0.0084) and 15.9% for the Belgian Malinois (P=0.0241). It was observed in physiological, blood and ECG parameters differences between M1 and M2 (P<0.05). Other findings included a lower rest QTc value at T0 after training (P=0.0194). The chosen training led to a better fitness of the police dogs as all of them worked more intensively with a low cardiovascular requirement in M2. In conclusion, current exercise protocol in a treadmill improved dogs fitness, when we analysed ECG, physiological and blood parameters, making possible that animals may be used in more extended and multiple missions, contributing welfare of these animals.

The structural, thermal, electrical and mechanical properties of fully dense B 4 C ceramics, sintered using Spark Plasma Sintering (SPS), were studied and compared to the properties of B 4 C ceramics previously published in the literature. New results on B 4 C's mechanical responses were obtained by nanoindentation and ring-on-ring biaxial strength testing. The findings contribute to a more complete knowledge of the properties of B 4 C ceramics, an important material in many industrial applications.Materials 2020, 13, 1612 2 of 21 bonds, the intericosahedral bonds and the highly delocalized intraicosahedral sp2 bonds [5]; and their localization and delocalization, iconicity and covalent character along with the electron density determine the properties of B 4 C [15][16][17][18][19]. Group theory predicts 5A 1g + 2A 1u + 2A 2g + 6A 2u + 7E g + 8E u representation for the normal modes of lattice dynamics of R3m rhombohedral B 4 C, where the 12 modes of A 1g and Eg symmetry are Raman active, the 14 modes of A 2u and E u symmetry are Infrared (IR) active and the A 1u and the A 2g modes are optically inactive. When the zero-frequency modes are removed, the number of IR active modes become 12 [20]. If carbon atoms are introduced into the icosahedron, a higher number of vibrational modes can be expected in the collected spectra [5].It was reported that B 4 C exhibits a strong anisotropy of the elastic constants, meaning that elastic moduli are orientation dependent [21]. It was found that the Young's modulus of B 5.6 C single crystal has a maximum E max = 522 GPa along the [111] direction and a minimum Emin = 64 GPa and a maximum shear modulus Gmax = 233 GPa along the [201] direction and Gmin = 165 GPa in the [112] direction [5]. The elastic moduli of isotropic polycrystalline B 4 C have a dependence on the stoichiometry of the B or C atoms [22][23][24][25][26]. While B 4 C exhibits high elastic moduli, determined by the atomic bonding in the compound, the extremely rigid framework arising from the covalently bonded icosahedra and chain units leads to their refractory nature and extreme hardness [27]. B 4 C shows good flexure strength, which is dependent on external factors, such as processing conditions, size of the samples tested, grain size, porosity, presence of defects and so forth. Because B 4 C ceramic is relatively brittle, it shows a strong flaw sensitivity, where defects play a detrimental role and often are responsible for premature failure. Therefore, there has been a significant effort to improve the compaction technologies to provide enhancement in sintering, with the majority of the techniques used for densification of B 4 C being pressureless sintering [28][29][30][31][32], hot pressing [33][34][35][36], hot isostatic pressing [37], direct current sintering [38][39][40][41][42], high pressure sintering in multi-anvil apparatus [43] and contactless flash sintering [44] techniques. Currently, the most accepted and well developed processing technique for densification of B 4 C is the direct current sinterin...