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Despite the need for quantitative measurements of light intensity across many scientific disciplines, existing technologies for measuring light dose at the sample of a fluorescence microscope cannot simultaneously retrieve light intensity along with spatial distribution over a wide range of wavelengths and intensities. To address this limitation, we developed two rapid and straightforward protocols that use organic dyes and fluorescent proteins as actinometers. The first protocol relies on molecular systems whose fluorescence intensity decays and/or rises in a monoexponential fashion when constant light is applied. The second protocol relies on a broad-absorbing photochemically inert fluorophore to back-calculate the light intensity from one wavelength to another. As a demonstration of their use, the protocols are applied to quantitatively characterize the spatial distribution of light of various fluorescence imaging systems, and to calibrate illumination of commercially available instruments and light sources. more...

Solving the forestry logistic problem is involved with multiple short- and long-term operational decisions such as truck routing, inventory management, and scheduling. Although these problems are separately studied in the literature, but in many situations, a near-optimal solution of the “comprehensive” problem suffices the managerial needs and directions. In this paper, we consider the forestry logistic and use a simulation-optimization method to reach a near-optimal solution. This method enables us to incorporate different uncertainties such as stochastic travel time and occurrence of external factors. We use real-world data to evaluate our model and measure the complexity of real-world constraints. more...

• An approach is proposed for estimating monotonic change point in multistage process. • The quality of the process at each stage is characterized by simple linear profiles. • Two SVM algorithms are proposed for identifying the occurrence and type of change. • MLE is proposed for estimating both single and multiple monotonic change points. • The performance of the proposed approach is evaluated under various scenarios. In this paper, a hybrid method is proposed for estimating monotonic change points in multistage processes where, at each stage, the quality of the process is represented by simple linear profile models. In the case of monotonic changes, the change type is not known a priori, and the only assumption is that the changes are non-decreasing or non-increasing in nature. In the proposed method, a support vector machine (SVM) algorithm is first developed to identify the parameters experiencing a change in each process stage. Then, the second SVM algorithm is applied to identify the type of change occurring in the related parameters. Finally, considering the identified parameters and change types, the maximum likelihood estimator (MLE) is proposed to estimate the change points of the process under different scenarios, including single and multiple change points, upward and downward step changes, increasing and decreasing linear trends, shift in both parameters of the profiles, shift in different stages of the process, and weak and strong autocorrelation coefficients. The performance of the proposed method is evaluated through extensive simulation experiments. The results indicate that the proposed method recognizes the patterns and estimates the monotonic change points accurately. [ABSTRACT FROM AUTHOR] more...

Two most promising treatment strategies for multiple sclerosis (MS) are the administration of mesenchymal stem cells (MSCs) and targeted delivery of cerebrolysin. Comparing these treatment plans as a source of neurotrophic factors (NTFs) can inform future MS treatment guidelines. This study was carried out on the experimental autoimmune encephalomyelitis as an animal model of MS through NTFs-loaded TGN-modified chitosan nanoparticles (NTFs@TCN) and MSCs administration. The clinical scores considerations and evaluation of biological samples were shown significant improvement in locomotion activity accompanied by a decrease in lymphocyte infiltration on spinal cord tissues in the NTFs@TCN received group. These alterations may be modulated through GATA3/FOXP3 and targeting Th1/2 cells pathways. Our data shows that the targeted drug delivery strategies and high accessibility to the central nervous system may be a suitable option in the management of MS compared to cell therapy and pure NTFs administration. more...

In cognitive radio, accurate spectrum sensing is essential to optimally use the available spectrum opportunities. On the other hand, energy is a scarce resource especially in cognitive sensor networks. In this study, the authors combine both these conflicting requirements and propose an energy-aware secondary user selection algorithm for cognitive sensor networks. First, an optimisation problem is solved to obtain the minimum required number of cognitive users, whereas satisfying the system requirements. Second, the most eligible cognitive users are identified through a probability-based approach. They study two extreme cases by focusing on either energy or accuracy parameters. By numerical analysis, it is shown that the accuracy benchmark is increased by as much as 39% by only considering the sensing accuracy, and the energy benchmark is reduced by as low as 76% by only considering the remaining level of energy. In addition, they conduct computer simulation and compare the network's lifetime at several sensing accuracy thresholds. It is elaborated that greater sensing accuracy thresholds lead to longer network lifetime. Finally, the effects of several fusion rules on the proposed method are studied through simulation and numerical analyses. It is discussed that the Majority rule has the best performance among the examined rules. more...

Catalase is an important antioxidant enzyme that catalyzes the disproportionation of H2O2into harmless water and molecular oxygen. Due to various applications of the enzyme in different sectors of industry as well as medicine, the enhancement of stability of the enzyme is important. Effect of various classes of compatible as well as noncompatible osmolytes on the enzymatic activity, disaggregation, and thermal stability of bovine liver catalase have been investigated. Compatible osmolytes, proline, xylitol, and valine destabilize the denatured form of the enzyme and, therefore, increase its disaggregation and thermal stability. The increase in the thermal stability is accompanied with a slight increase of activity in comparison to the native enzyme at 25 °C. On the other hand, histidine, a noncompatible osmolyte stabilizes the denatured form of the protein and hence causes an overall decrease in the thermal stability and enzymatic activity of the enzyme. Chemometric results have confirmed the experimental results and have provided insight into the distribution and number of mole fraction components for the intermediates. The increase in melting temperature (Tm) and enzymatic rate could be further amplified by the intrinsic effect of temperature enhancement on the enzymatic activity for the industrial purposes. more...

The authors address an important aspect of spectrum sensing that has been often overlooked in the cognitive radio (CR) research. Although CR is supposed to be aware of its surrounding, most existing articles do not consider the characteristics of secondary users in the optimisation of sensing period. In this study, based on a continuous-time Markov chain model for cognitive sensor networks and energy detection method, the authors propose an application-specific spectrum sensing method that obtains the optimal sensing period according to the characteristics of both ‘primary and secondary’ users (hybrid scheme). The authors define and analytically derive two parameters, the interference ratio and the undetected opportunity ratio, and analytically find the optimum sensing period. Numerical and simulation results indicate that our proposed method is able to provide an optimal sensing period, that is customised for different cognitive networks. The proposed method significantly increases the system throughput by up to 11% and reduces the network's power consumption by as low as 33%. Finally, the trade-off between the throughput maximisation and power consumption minimisation is discussed. more...

Cognitive radio concept has been widely researched to improve the spectrum usage efficiency. Appropriate modelling of the spectrum occupancy by both licensed and unlicensed users is necessary to do clear system analysis in a cognitive framework. In this paper, a continuous-time Markov chain model is developed to better describe the radio spectrum usage. The state space vector and the transition rate matrix that completely describe the system are obtained; a steady-state analysis is performed and the stationary state probability (SSP) vector is derived. In addition, we take into account the inaccuracy of the existing spectrum sensing model (missed opportunities), and derive an improved expression for the maximum throughput of secondary users as a function of the primary user traffic parameters and the achieved opportunity ratio (AOR). The optimum sensing period that maximises AOR is also analytically obtained. The proposed model and the derived expressions were examined through numerical analysis and compared with the existing models. This model is very general and applicable to systems with N secondary users in the vicinity of the primary user. more...

Six patients underwent emergency surgery for descending aortic injury following blunt trauma to the chest; three survived. Associated injury was a critical factor in two of the three patients who died. In the third patient, prolonged ischemia of the lower half of the body due to total aortic distraction with a distal aortic flap produced irreversible changes that were manifest during reperfusion of the body. Angiography is recommended if the patient's condition is stable and other injuries demanding immediate surgical attention are not present. If, however, there are other serious injuries and adequate distal perfusion, then these other injuries should be corrected before aortic repair is undertaken. more...

The formation of protein corona (PC) around nanoparticles (NPs) has been reported inside biological conditions. This effect can alter delivery capacity toward the targeted tissues. Here, we synthesized folic acid-modified chitosan NPs (FA-CS NPs) using different concentrations of folic acid (5, 10, and 20%). FA-CS NPs were exposed to plasmas of breast cancer patients and healthy donors to evaluate the possibility of PC formation. We also monitored uptake efficiency in in vitroconditions after incubation with human breast cancer cell line MDA-MB-231 and monocyte/macrophage-like Raw264.7 cells. Data showed that the formation of PC around FA-CS NPs can change physicochemical properties coincided with the rise in NP size and negative surface charge. SDS-PAGE electrophoresis revealed differences in the type and content rate of plasma proteins attached to NP surface in a personalized manner. Based on MTT data, the formation of PC around NPs did not exert cytotoxic effects on MDA-MB-231 cells while this phenomenon reduced uptake rate. Fluorescence imaging and flow cytometry analyses revealed reduced cellular internalization rate in NPs exposed to patients’ plasma compared to the control group. In contrast to breast MDA-MB-231 cells, Raw264.7 cells efficiently adsorbed the bare and PC-coated NPs from both sources, indicating the involvement of ligand–receptor-dependent and independent cellular engulfment. These data showed that the PC formed on the FA-CS NPs is entirely different in breast cancer patients and healthy counterparts. PC derived from patients’ plasma almost abolishes the targeting efficiency of FA-CS NPs even in different mechanisms, while this behavior was not shown in the control group. Surprisingly, Raw264.7 cells strongly adsorbed the PC-coated NPs, especially when these particles were in the presence of patients’ sera. It is strongly suggested that the formation of PC around can affect delivering capacity of FA-CS NPs to cancer cells. It seems that the PC-coated FA-CS NPs can be used as an efficient delivery strategy for the transfer of specific biomolecules in immune system disorders. more...