Stability of red beet pigment concentrate in maize starch

Two pigment concentrates, differentiated as dark (D) and rose (R), were prepared from fermented red beet (Beta vulgaris L var rubra) and applied to two types of maize starch, industrial (IS) and modified (MS). The samples were stored for 191 days at room temperature. The decay of the two red pigments in the two maize starches was DIS 12.70%, DMS 9.43%, RIS 14.15%, RMS 8.54% and followed a first order reaction. The modified maize starch was found to be the most suitable carrier of the pigment. Water activity played a determining role in this result.     

Human robot cooperation with compliance adaptation along the motion trajectory

In this paper we propose a novel approach for intuitive and natural physical human–robot interaction in cooperative tasks. Through initial learning by demonstration, robot behavior naturally evolves into a cooperative task, where the human co-worker is allowed to modify both the spatial course of motion as well as the speed of execution at any stage. The main feature of the proposed adaptation scheme is that the robot adjusts its stiffness in path operational space, defined with a Frenet–Serret frame. Furthermore, the required dynamic capabilities of the robot are obtained by decoupling the robot dynamics in operational space, which is attached to the desired trajectory. Speed-scaled dynamic motion primitives are applied for the underlying task representation. The combination allows a human co-worker in a cooperative task to be less precise in parts of the task that require high precision, as the precision aspect is learned and provided by the robot. The user can also freely change the speed and/or the trajectory by simply applying force to the robot. The proposed scheme was experimentally validated on three illustrative tasks. The first task demonstrates novel two-stage learning by demonstration, where the spatial part of the trajectory is demonstrated independently from the velocity part. The second task shows how parts of the trajectory can be rapidly and significantly changed in one execution. The final experiment shows two Kuka LWR-4 robots in a bi-manual setting cooperating with a human while carrying an object.     

Influence of pH and Ionic Impurities on the Adsorption of Poly(acrylic) Dispersant onto a Zinc Oxide Surface

We have studied the properties of aqueous suspensions of ZnO powders with different purities. Our results suggest that powder purity determines the amount of dispersant necessary to form a stable aqueous suspension as well as the maximum adsorption capacity of the dispersant: the higher the positive surface charge of the as-received ZnO powders, the higher the amount of dispersant adsorbed onto the metal oxide surface. The surface charge of the ZnO particles in suspension is affected by the concentration of zinc as well as sulfate ions, which are the major impurities in the supernatant. The pH of the aqueous ZnO suspensions increases with increasing concentration of poly(acrylic) dispersant until the maximum adsorption capacity is attained. Further additions of dispersant do not increase the pH because of a buffer formation with impurity ions.     

Finite element modeling and experimental proof of NEMS-based silicon pillar resonators for nanoparticle mass sensing applications

The potential use of nanoelectromechanical systems (NEMS) created in silicon nanopillars (SiNPLs) is investigated in this work as a new generation of aerosol nanoparticle (NP)-detecting device. The sensor structures are created and simulated using a finite element modeling (FEM) tool of COMSOL Multiphysics 4.3b to study the resonant characteristics and the sensitivity of the SiNPL for femtogram NP mass detection in 3-D structures. The SiNPL arrays use a piezoelectric stack for resonance excitation. To achieve an optimal structure and to investigate the etching effect on the fabricated resonators, SiNPLs with different designs of meshes, sidewall profiles, heights, and diameters are simulated and analyzed. To validate the FEM results, fabricated SiNPLs with a high aspect ratio of approximately 60 are used and characterized in resonant frequency measurements where their results agree well with those simulated by FEM. Furthermore, the deflection of a SiNPL can be enhanced by increasing the applied piezoactuator voltage. By depositing different NPs [i.e., gold (Au), silver (Ag), titanium dioxide (TiO₂), silicon dioxide (SiO₂), and carbon black NPs] on the SiNPLs, the decrease of the resonant frequency is clearly shown confirming their potential to be used as airborne NP mass sensor with femtogram resolution level. A coupling concept of the SiNPL arrays with piezoresistive cantilever resonator in terms of the mass loading effect is also studied concerning the possibility of obtaining electrical readout signal from the resonant sensors.     

Comprehensive Flow-Cytometric Quality Assessment of Ram Sperm Intended for Gene Banking Using Standard and Novel Fertility Biomarkers

Flow cytometry becomes a common method for analysis of spermatozoa quality. Standard sperm characteristics such as viability, acrosome and chromatin integrity, oxidative damage (ROS) etc. can be easily assess in any animal semen samples. Moreover, several fertility-related markers were observed in humans and some other mammals. However, these fertility biomarkers have not been previously studied in ram. The aim of this study was to optimize the flow-cytometric analysis of these standard and novel markers in ram semen. Ram semen samples from Slovak native sheep breeds were analyzed using CASA system for motility and concentration and were subsequently stained with several fluorescent dyes or specific antibodies to evaluate sperm viability (SYBR-14), apoptosis (Annexin V, YO-PRO-1, FLICA, Caspases 3/7), acrosome status (PNA, LCA, GAPDHS), capacitation (merocyanine 540, FLUO-4 AM), mitochondrial activity (MitoTracker Green, rhodamine 123, JC-1), ROS (CM-H₂DCFDA, DHE, MitoSOX Red, BODIPY), chromatin (acridine orange), leukocyte content, ubiquitination and aggresome formation, and overexpression of negative biomarkers (MKRN1, SPTRX-3, PAWP, H3K4me2). Analyzed semen samples were divided into two groups according to viability as indicators of semen quality: Group 1 (viability over 60%) and Group 2 (viability under 60%). Significant (p < 0.05) differences were found between these groups in sperm motility and concentration, apoptosis, acrosome integrity (only PNA), mitochondrial activity, ROS production (except for DHE), leukocyte and aggresome content, and high PAWP expression. In conclusion, several standard and novel fluorescent probes have been confirmed to be suitable for multiplex ram semen analysis by flow cytometry as well as several antibodies have been validated for the specific detection of ubiquitin, PAWP and H3K4me2 in ram spermatozoa.     

Limit Complexities Revisited

The main goal of this article is to put some known results in a common perspective and to simplify their proofs.     

Phasen der SOA-Einf��hrung

The paper argues that attitudes to SOA follow a typical hype cycle from Technological Trigger, Peak of Inflated Expectations, and a Trough of Disillusionment to the more recent realization that SOA is a concept that may offer certain benefits but has several limitations. The main research question studies how the attitude to SOA changes in various phases of the hype cycle, how the SOA implementation cycle and an increase in business process maturity (BPMa) are interconnected and which factors influence the transition between the hype cycle phases. The paper shows that an organization??s success with implementing SOA depends on its ability to match the SOA implementation with an increase in BPMa. The dual purpose of implementing SOA is shown in the first framework: to assure the coherence of IT assets and to assure business/IT alignment. In the second framework, the interconnection of SOA and BPMa and its role in transiting through the hype cycle phases is outlined. The findings are analyzed using a longitudinal case study of a large Slovenian company.     

划痕对AZ80镁合金上磷酸钙转化涂层耐腐蚀性能的影响

通过电化学测试、扫描振动电极技术、浸泡实验和析氢实验分析AZ80合金、磷酸钙转化涂层以及含划痕涂层的耐腐蚀性能,进而研究划痕对AZ80镁合金上磷酸钙转化膜腐蚀行为的影响.结果表明,AZ80合金经涂层处理后腐蚀性能提高,其腐蚀电流密度由(85±4)μA/cm2降低为(4±1)μA/cm2.当涂层被破坏后,其对基体的保护能...