Blind localization of heating in neural tissues induced by a train of the infrared pulse laser

Introduction: Recently, infrared lasers (wavelengths larger than 1100 nm) have been applied to stimulate neural tissues. Infrared neural stimulation (INS) has some advantages over conventional electric stimulation, including contact-free delivery, spatial precision, and lack of stimulation artifacts. In this study and based on a photothermal mechanism, we applied the heat diffusion equation to study temperature variation of a biological phantom during INS. In addition, the impact of laser parameters on spatially localized heating induced by two different infrared wavelengths were studied.Method: We studied the localization of INS inside a phantom similar to cortical neural tissue. First, we analytically solved the heat diffusion equation to study the distribution of temperature inside this phantom. Then, the accuracy of analytical results was verified by heating the phantom using amplitude-modulated infrared lasers (lambda= 1450 and 1500 nm, the energy between 2 and 5 mJ and pulse duration up to 20 ms). The laser light was directed to sample by a multimode optical fiber (NA=0.22, Core size= 200 microns). Finally, the impacts of laser properties on the spatial resolution of infrared heating were discerned.Result: In order to verify analytical results, we measured the maximum temperatures of the phantom during illumination of lasers and compared them with analytical results. The analytical results were in agreement with the experimental results. The effects of laser beam properties such as pulse duration, energy and repetition rate frequency on the spatial resolution were investigated. The results indicated that the spatial resolution of INS can be smaller than one millimeter.Conclusion: Here, the influences of laser properties on the localization of INS inside a biological phantom were studied. These results can be applied to improve the spatial selectivity of the peripheral nerve interface. 

Minimizing the AoI in Resource-Constrained Multi-Source Relaying Systems: Dynamic and Learning-based Scheduling

We consider a multi-source relaying system where the independent sources randomly generate status update packets which are sent to the destination with the aid of a relay through unreliable links. We develop transmission scheduling policies to minimize the sum average age of information (AoI) subject to transmission capacity and long-run average resource constraints. We formulate a stochastic control optimization problem. To solve the problem, a constrained Markov decision process (CMDP) approach and a drift-plus-penalty method are proposed. The CMDP problem is solved by transforming it into an MDP problem using the Lagrangian relaxation method. We theoretically analyze the structure of optimal policies for the MDP problem and subsequently propose a structure-aware algorithm that returns a practical near-optimal policy. By the drift-plus-penalty method, we devise a dynamic near-optimal low-complexity policy. We also develop a model-free deep reinforcement learning policy, which does not require the full knowledge of system statistics. To do so, we employ the Lyapunov optimization theory and a dueling double deep Q-network. Simulation results are provided to assess the performance of our policies and validate the theoretical results. The results show up to 91% performance improvement compared to a baseline policy.Comment: 30 Pages, preliminary results of this paper were presented at IEEE Globecom 2021, https://ieeexplore.ieee.org/document/968594

Effect of Nettle Extract and Pumpkin Seed on Prostate Specific Antigen and Urinary Symptoms in Patients Taking Alfa-blocker for Benign Prostatic Hyperplasia

Introduction: We aimed to compare the effect of nettle extract and pumpkin seed on Prostate Specific Antigen (PSA) and international prostate symptoms score (IPSS) in patients taking alfa-blocker for benign prostatic hyperplasia (BPH). Materials and Methods: For this purpose, 90 outpatients were studied in three groups, including men over 40 years of age with benign prostatic enlargement. The first group (Urtidin) contained consumers of nettle extract from Barijessence Company called Urtidin tablets with tamsulosin; the second group took tablets containing pumpkin seed extract called Prosta Barij and tamsulosin; the third group (Control) received only tamsulosin for three months. Patients were not randomly assigned to the groups PSA, IPSS, and related factors were evaluated and analyzed using SPSS software. Results: 89 patients completed the study (30/89 in Urtidin group with a mean age of 62.4±7.39 years, 29/89 in Prosta Barij group with a mean age of 65.9±7.32 years, and 30/89 in the control group with a mean age of 64.7±8.64 years). The results showed that nettle and pumpkin seed extracts affect PSA in patients taking tamsulosin for BPH. Also, after the intervention, IPSS had a significant decrease compared with baseline in both drug treatment groups. There was no significant difference in these three types of treatment. Conclusion: It seems that the desired herbal products did not have a synergistic effect with alpha blockers in the control and treatment of BPH but they can affect the serum PSA level

A systematic literature review on source code similarity measurement and clone detection: techniques, applications, and challenges

Measuring and evaluating source code similarity is a fundamental software engineering activity that embraces a broad range of applications, including but not limited to code recommendation, duplicate code, plagiarism, malware, and smell detection. This paper proposes a systematic literature review and meta-analysis on code similarity measurement and evaluation techniques to shed light on the existing approaches and their characteristics in different applications. We initially found over 10000 articles by querying four digital libraries and ended up with 136 primary studies in the field. The studies were classified according to their methodology, programming languages, datasets, tools, and applications. A deep investigation reveals 80 software tools, working with eight different techniques on five application domains. Nearly 49% of the tools work on Java programs and 37% support C and C++, while there is no support for many programming languages. A noteworthy point was the existence of 12 datasets related to source code similarity measurement and duplicate codes, of which only eight datasets were publicly accessible. The lack of reliable datasets, empirical evaluations, hybrid methods, and focuses on multi-paradigm languages are the main challenges in the field. Emerging applications of code similarity measurement concentrate on the development phase in addition to the maintenance.Comment: 49 pages, 10 figures, 6 table

Application of lactobionic acid and nonionic surfactants as solubilizing agents for parenteral formulation of clarithromycin

Purpose: The purpose of this paper is to enhance the solubility of clarithromycin (CLR) using nonionic surfactants and some type of acids for preparation of the new formulations. Methods: Myrj 52 and chremophor (2.5 and 5% w/v) were used in two concentrations. To investigate solubility, the formulations were shaken for 48 hours at room temperature. For stability test, lyophilized samples were maintained in refrigerator at 4° C, and in oven at 40° C. Drug analysis was performed by reverse phase high performance liquid chromatography (HPLC) with ultraviolet detection. Results: Solubility tests indicated that lactobionic acid was the most effective to increase clarithromycin solubility and chremophor showed higher enhancing effect than myrj 52 on CLR solubility. The stability tests results also confirmed that shelf-lives of all formulations have been the equivalent to 24 months. Conclusion: On the whole, formulations described in this article may be very suitable for industrial-scale manufacturing and clinical application