Contributors:Chao-rui Li, Si-liang Li, Guan-qun Wang, Zheng-yin Yang
In this study, a novel fluorescein-derived Schiff-base ligand bearing a chromone moiety which was called 6-Hydroxy-3-formylchromone fluorescein hydrazone (1) has been designed, synthesized and evaluated as a Mg2+ “turn on” fluorescent probe. This probe 1 exhibited high selectivity and sensitivity towards Mg2+ over other important metal ions investigated, and the remarkable enhancement in fluorescence emission centered at 504nm was observed in the presence of Mg2+, which was attributed to the ring-opening process of the fluorescein fluorophore in probe 1 upon complexation of 1 with Mg2+. Furthermore, the “turn on” response of this probe 1 to Mg2+ was nearly completed within 3min, which indicated that this probe 1 could be utilized to sense and monitor Mg2+ for real-time detection.
This research study investigates the tribological behaviour of titanium oxide (TiO2) nanoparticles as additives in mineral based multi-grade engine oil. All tests were performed under variable load and varying concentrations of nanoparticles in lubricating oil. The friction and wear experiments were performed using pin-on-disc tribotester. This study shows that mixing of TiO2 nanoparticles in engine oil significantly reduces the friction and wear rate and hence improves the lubricating properties of engine oil. The dispersion analysis of TiO2 nanoparticles in lubricating oil using UV spectrometer confirms that TiO2 nanoparticles possess good stability and solubility in the lubricant and improve the lubricating properties of the engine oil.
Contributors:Elena Cordero, Maurice de Gosson, Fabio Nicola
One of the most popular time-frequency representation is certainly the Wigner distribution. To reduce the interferences coming from its quadratic nature, several related distributions have been proposed, among which the so-called Born-Jordan distribution. It is well known that in the Born-Jordan distribution the ghost frequencies are in fact damped quite well, and the noise is in general reduced. However, the horizontal and vertical directions escape from this general smoothing effect, so that the interferences arranged along these directions are in general kept. Whereas these features are graphically evident on examples and heuristically well understood in the engineering community, there is not at present a mathematical explanation of these phenomena, valid for general signals in L2 and, more in general, in the space S′ of temperate distributions. In the present note we provide such a rigorous study using the notion of wave-front set of a distribution. We use techniques from Time-frequency Analysis, such as the modulation and Wiener amalgam spaces, and also results of microlocal regularity of linear partial differential operators.
Mycobacterium tuberculosis, acid fast bacilli from the family of Mycobacteriaceae, is the causative agent of most cases of tuberculosis. Tuberculosis, as a communicable disease, remains a serious public health threat, killing more than one million people globally every year. Primary diagnosis of tuberculosis bacilli (TB) relies mainly on microscopic detection of acid fast bacilli (AFB), but the method suffers from low sensitivity and the results largely depend on the technician’s skill. New diagnostic tools are necessary to be introduced for rapid and accurate detection of the bacilli in sputum samples. We, in collaboration with Anda Biologicals, have developed a new platform, named as “Patho-tb”, for rapid detection of AFB with high sensitivity and with low dependence on human skills. Evaluation of Patho-tb test performance was done in two settings: (1) primary field study conducted using 38 sputa from high TB prevalence area of Iran (Zabol city near to the Afghanistan border), and (2) main study conducted using 476 sputa from Tehran, capital of Iran. Patho-tb was applied for processed sputum samples in parallel with routine diagnostic methods (including AFB microscopy, culture and PCR). All test results were compared to final clinical diagnostic state of an individual and diagnostic sensitivity (DSe), specificity, positive predictive value, negative predictive value and accuracy of each test results were calculated using standard formulations. Analytical sensitivity and specificity of the Patho-tb test were also determined. Calculated values for five above mentioned parameters are as follows: for field study: AFB (DSe: 29.6, DSp: 81.8, PPV: 80, NPV: 23.1, AC: 44.7), Patho-tb (DSe: 63, DSp: 72.7, PPV: 85, NPV: 44.4, AC: 65.8), and for main study: AFB (DSe: 86.1, DSp: 99.4, PPV: 98.5, NPV: 93.9, AC: 95.2), Patho-tb (DSe: 97.4, DSp: 92.9, PPV: 86.5, NPV: 98.7, AC: 94.3). Reproducibility of Patho-tb test results were near to 100% (Cohen’s kappa value between 0.85 and 1). The detection limit of Patho-tb test with 100% positivity rate was 3×103cells/ml of sputum. In the field study, Patho-tb test was 33.4% more sensitive than AFB microscopy, while the improvement was only 11.3% during the main study. Patho-tb results are easy to interpret and the test can be merged with other screening tests, like AFB. Totally, Patho-tb test alone or in conjunction with AFB microscopy is a useful screening tool for TB detection especially in poor geographical lab conditions.
A recent new research has revealed that real life systems follow similar “fractals-general” stacking behavior during their change pathways when subjected to affecting environments and events “on and above” their normal behavior or set points. In this paper, the system change pathway is investigated through cleverly neutralizing time in the analysis. The new expression of “neutralizing time” is defined as time is not considered during the system stack-based change pathway calculations, but it will only be sensed in the sequence order. By adopting this concept, the formulations cleverly avoid falling in the trap of the long dilemma of “the problem of time” when handling the system change pathways. This is equivalent to representing the system by two-level configuration: the basic level of the physical system is considered as temporal, while the upper level of affecting events is regarded as non-temporal. Furthermore, it is shown that the infinite multi-stacking interactions at any event state of global systems could provide the necessary mathematical platform for analyzing the natural or intentionally induced “synchronicity” principle. Two illustrative examples are presented to demonstrate the successful applicability of the new time neutralized concept. The first example describes the course of life of inverted pendulum trolley car subject to accidents and collision influences. The second example elucidates the change pathway of the formation of human bladder spherical crystalline stone versus different change formulas under excessive salt/mineral concentrations influences. It is revealed that these illustrative examples could provide a positive assertive answer to the important question: “Can the presented change pathway theory through backward stacking, neutralized time effect, and satisfying the reversibility property mathematically uncover many open secrets such as the origins of matter and antimatter?”. Applications of the new concept to some real life single stacking and multi-stacking examples are also discussed. It is recommended that future work shall be directed toward strengthening the new concept for multi-stacking system change pathway platforms. Such recommendation could also be generalized for implementing the concept in retrospective or backward stacking way to various real life applications, such as for analyzing the past sequential (evolutionary) formation of matter/substances and uncovering the mysterious origins of many versatile systems.
New advances have recently been made in the field of molecular genetics and mouse modeling of meningiomas, opening new perspectives for future treatments. Recent genome-wide genotyping and exome sequencing studies have confirmed the pivotal role of NF2 in meningioma tumorigenesis, concerning roughly half of the tumors, and unraveled new mutations in non-NF2 meningiomas concerning AKT1, SMO, KLF4 and TRAF7. The molecular mechanisms underlying tumorigenesis of high histological grades have been progressively deciphered with the recent discovery of TERT promoter mutations in progressing tumors. A better understanding of the genetics and clinical behavior of high-grade meningiomas is mandatory in order to better design future clinical trials. New genetically engineered mouse models of benign and histologically aggressive meningioma represent a substantial resource for the establishment of relevant pre-clinical trials. By studying the mechanisms underlying these new tumorigenesis pathways and the corresponding mouse models, we should be able to offer personalized chemotherapy to patients with surgery- and radiation-refractory meningiomas in the near future.
The influence of Direct Torque Controlled Induction Motor Drive in the area of industrial application is very high; it presents foremost area of controllability of load at different states of operation. The major snags to the controller are maintaining Constant Switching Frequency and Infeasibility state. This paper concentrates on rectifying these problems with Modified Multiband Hysteresis Controller and Nearest Vector Control Modulated Asymmetrical Cascaded H-Bridge Multilevel Inverter for the better drive operation. In this case proper modification in MHC gives the optimal utilizations of each control vector to avoid the infeasibility states with a Lookup-Table and Multilevel Inverter gives more number of control voltage vectors with constant switching frequency for flexible operation of drive with low disturbances. Direct Torque Control equipped with these two modules achieves better operating conditions with low Torque ripples, low distorted flux and speed with different loads, and all other satisfactory load operating parameters.
Contributors:A.M. Tormos, S. Rius-Pérez, S. Pérez, R. Taléns-Visconti
La enfermedad de Alzheimer (EA) es la principal enfermedad neurodegenerativa cortical. Su incidencia aumenta con la edad, lo que provoca importantes problemas médicos, sociales y económicos, especialmente en países con población envejecida.