99mTc-HDP Labeling—A Non-Destructive Method for Real-Time Surveillance of the Osteogenic Differentiation Potential of hMSC during Ongoing Cell Cultures

99-Metastabil Technetium (^99mTc) is a radiopharmaceutical widely used in skeletal scintigraphy. Recent publications show it can also be used to determine the osteogenic potential of human mesenchymal stem cells (hMSCs) by binding to hydroxyapatite formed during bone tissue engineering. This field lacks non-destructive methods to track live osteogenic differentiation of hMSCs. However, no data about the uptake kinetics of ^99mTc and its effect on osteogenesis of hMSCs have been published yet. We therefore evaluated the saturation time of ^99mTc by incubating hMSC cultures for different periods, and the saturation concentration by using different amounts of ^99mTc activity for incubation. The influence of ^99mTc on osteogenic potential of hMSCs was then evaluated by labeling a continuous hMSC culture three times over the course of 3 weeks, and comparing the findings to cultures labeled once. Our findings show that ^99mTc saturation time is less than 0.25 h, and saturation concentration is between 750 and 1000 MBq. Repeated exposure to γ-radiation emitted by ^99mTc had no negative effects on hMSC cultures. These new insights can be used to make this highly promising method broadly available to support researchers in the field of bone tissue engineering using this method to track and evaluate, in real-time, the osteogenic differentiation of hMSC, without any negative influence on the cell viability, or their osteogenic differentiation potential.     

Gas-Plasma-Activated Water Impact on Photo-Dependent Dormancy Mechanisms in Nicotiana tabacum Seeds

Seeds sense temperature, nutrient levels and light conditions to inform decision making on the timing of germination. Limited light availability for photoblastic species results in irregular germination timing and losses of population germination percentage. Seed industries are therefore looking for interventions to mitigate this risk. A growing area of research is water treated with gas plasma (GPAW), in which the formed solution is a complex consisting of reactive oxygen and nitrogen species. Gas plasma technology is widely used for sterilisation and is an emerging technology in the food processing industry. The use of the GPAW on seeds has previously led to an increase in germination performance, often attributed to bolstered antioxidant defence mechanisms. However, there is a limited understanding of how the solution may influence the mechanisms that govern seed dormancy and whether photoreceptor-driven germination mechanisms are affected. In our work, we studied how GPAW can influence the mechanisms that govern photo-dependent dormancy, isolating the effects at low fluence response (LFR) and very low fluence response (VLFR). The two defined light intensity thresholds affect germination through different phytochrome photoreceptors, PHYB and PHYA, respectively; we found that GPAW showed a significant increase in population germination percentage under VLFR and further described how each treatment affects key physiological regulators.     

Biomarkers in Systemic Juvenile Idiopathic Arthritis,Macrophage Activation Syndrome and Their Importance in COVID Era

Systemic juvenile idiopathic arthritis (sJIA) and its complication, macrophage activation syndrome (sJIA-MAS), are rare but sometimes very serious or even critical diseases of childhood that can occasionally be characterized by nonspecific clinical signs and symptoms at onset—such as non-remitting high fever, headache, rash, or arthralgia—and are biologically accompanied by an increase in acute-phase reactants. For a correct positive diagnosis, it is necessary to rule out bacterial or viral infections, neoplasia, and other immune-mediated inflammatory diseases. Delays in diagnosis will result in late initiation of targeted therapy. A set of biomarkers is useful to distinguish sJIA or sJIA-MAS from similar clinical entities, especially when arthritis is absent. Biomarkers should be accessible to many patients, with convenient production and acquisition prices for pediatric medical laboratories, as well as being easy to determine, having high sensitivity and specificity, and correlating with pathophysiological disease pathways. The aim of this review was to identify the newest and most powerful biomarkers and their synergistic interaction for easy and accurate recognition of sJIA and sJIA-MAS, so as to immediately guide clinicians in correct diagnosis and in predicting disease outcomes, the response to treatment, and the risk of relapses. Biomarkers constitute an exciting field of research, especially due to the heterogeneous nature of cytokine storm syndromes (CSSs) in the COVID era. They must be selected with utmost care—a fact supported by the increasingly improved genetic and pathophysiological comprehension of sJIA, but also of CSS—so that new classification systems may soon be developed to define homogeneous groups of patients, although each with a distinct disease.     

A program nucleus for encoding and decoding calendar dates

A novel algorithm and subroutine is presented for encoding and decoding calendar dates. For encoding a numeric calendar date in the form day, month, year is converted into an integer variable in the range between 2(15) -1 and -2(15). With decoding this integer variable is converted into numeric day, month and year. The algorithm performs very quickly and takes only 7 lines of FORTRAN code for encoding and decoding respectively.     

Activity recognition of assembly tasks using body-worn microphones and accelerometers

In order to provide relevant information to mobile users, such as workers engaging in the manual tasks of maintenance and assembly, a wearable computer requires information about the user's specific activities. This work focuses on the recognition of activities that are characterized by a hand motion and an accompanying sound. Suitable activities can be found in assembly and maintenance work. Here, we provide an initial exploration into the problem domain of continuous activity recognition using on-body sensing. We use a mock "wood workshop” assembly task to ground our investigation. We describe a method for the continuous recognition of activities (sawing, hammering, filing, drilling, grinding, sanding, opening a drawer, tightening a vise, and turning a screwdriver) using microphones and three-axis accelerometers mounted at two positions on the user's arms. Potentially "interesting” activities are segmented from continuous streams of data using an analysis of the sound intensity detected at the two different locations. Activity classification is then performed on these detected segments using linear discriminant analysis (LDA) on the sound channel and hidden Markov models (HMMs) on the acceleration data. Four different methods at classifier fusion are compared for improving these classifications. Using user-dependent training, we obtain continuous average recall and precision rates (for positive activities) of 78 percent and 74 percent, respectively. Using user-independent training (leave-one-out across five users), we obtain recall rates of 66 percent and precision rates of 63 percent. In isolation, these activities were recognized with accuracies of 98 percent, 87 percent, and 95 percent for the user-dependent, user-independent, and user-adapted cases, respectively.     

Synthesis,Structure, Molecular Orbital and Valence Bond Calculations for Tetrazole Azide,CHN7

The synthesis, NMR spectroscopic characterization and structure determination of highly explosive tetrazole azide, a very nitrogen‐rich material (88.3% N) is reported. Tetrazole azide was prepared in high yield from the diazotation reaction of aminotetrazole, followed by treatment of the formed diazonium salt with sodium azide. Synthesis in diethylether/methanol and recrystallization from diethylether afforded colorless cubes: CHN₇ ( 1 ): monoclinic, P1 2₁/n₁, a=1346.6(5), b=499.6(2), c=1360.9(5) pm, β=105.14(1)⁰, V=0.884(2) nm³, Z=8, ϱ=1.670 g cm⁻³. The observed structural parameters (X‐ray) are in good accordance with the results from molecular orbital (MO) calculations. The computed electrostatic potential (B3LYP) suggests a pronounced shock and friction sensitivity which was confirmed experimentally. Quantitative valence bond (VB) calculations were performed for the most important 21 VB structures in order to obtain the structural weights and to obtain an assessment for the importance of the various individual VB structures considered.