Reinforcement-Learning-Based Routing and Resource Management for Internet of Things Environments: Theoretical Perspective and Challenges.

Internet of Things (IoT) devices are increasingly popular due to their wide array of application domains. In IoT networks, sensor nodes are often connected in the form of a mesh topology and deployed in large numbers. Managing these resource-constrained small devices is complex and can lead to high system costs. A number of standardized protocols have been developed to handle the operation of these devices. For example, in the network layer, these small devices cannot run traditional routing mechanisms that require large computing powers and overheads. Instead, routing protocols specifically designed for IoT devices, such as the routing protocol for low-power and lossy networks, provide a more suitable and simple routing mechanism. However, they incur high overheads as the network expands. Meanwhile, reinforcement learning (RL) has proven to be one of the most effective solutions for decision making. RL holds significant potential for its application in IoT device's communication-related decision making, with the goal of improving performance. In this paper, we explore RL's potential in IoT devices and discuss a theoretical framework in the context of network layers to stimulate further research. The open issues and challenges are analyzed and discussed in the context of RL and IoT networks for further study.

Sentiment Analysis of Students' Feedback in MOOCs: A Systematic Literature Review.

In recent years, sentiment analysis (SA) has gained popularity among researchers in various domains, including the education domain. Particularly, sentiment analysis can be applied to review the course comments in massive open online courses (MOOCs), which could enable instructors to easily evaluate their courses. This article is a systematic literature review on the use of sentiment analysis for evaluating students' feedback in MOOCs, exploring works published between January 1, 2015, and March 4, 2021. To the best of our knowledge, this systematic review is the first of its kind. We have applied a stepwise PRISMA framework to guide our search process, by searching for studies in six electronic research databases (ACM, IEEE, ScienceDirect, Springer, Scopus, and Web of Science). Our review identified 40 relevant articles out of 440 that were initially found at the first stage. From the reviewed literature, we found that the research has revolved around six areas: MOOC content evaluation, feedback contradiction detection, SA effectiveness, SA through social network posts, understanding course performance and dropouts, and MOOC design model evaluation. In the end, some recommendations are provided and areas for future research directions are identified.

A study of 25 zygomatic dental implants with 11 to 49 months' follow-up after loading.

PURPOSE: The purpose of this study was to evaluate indications, surgical problems, complications, and treatment outcomes related to the placement of zygomatic implants. A second aim was to determine any prosthetic difficulties and complications. MATERIALS AND METHODS: Twenty-five zygomatic implants were placed in 13 patients between April 1999 and December 2001. The patient age range was between 49 and 73 years, with a mean age of 59 years. All patients showed severe resorption of alveolar bone in the maxilla. All but 2 patients were smokers. Two patients had a history of cleft palate surgery, and 2 patients were known to be bruxers. Standard recommended surgical protocol was followed, and treatment was performed under general anesthesia. After abutment surgery, 9 patients received bar-retained overdentures, and 4 patients received fixed prostheses. RESULTS: No implants were lost, and few surgical complications were experienced. The follow-up period was 11 to 49 months. DISCUSSION: Although surgical problems precipitated by difficult anatomy in cleft patients and a patient with reduced interarch access were experienced, the results were favorable. Fabricating a functional and esthetic prosthesis can be a challenge. CONCLUSION: Zygomatic implants provide a treatment option for patients with severe maxillary resorption, defects, or situations where previous implant treatment has failed. In this experience, treatment with zygomatic implants was a predictable method with few complications, even in a group of patients that would not be considered ideal for implant treatment.

Conjugated polyelectrolytes--conformation-sensitive optical probes for staining and characterization of amyloid deposits.

Specific markers for diseases associated with protein aggregate depositions are of great interest. Here we report the use of conjugated polyelectrolytes as conformation-sensitive optical probes for histological labeling of amyloid deposits in ex vivo tissue samples-amyloid light chains in primary systemic amyloidosis, islet amyloid polypeptide in human pancreas, and Abeta amyloid in Alzheimer's disease. Under suitable conditions, these probes bind specifically to amyloid deposits, and this is seen as an orange-red emission from the polyelectrolyte. Furthermore, the probes emit light of different colors when bound to different amyloid deposits or other intracellular structures. This phenomenon is most probably due to differences in the protein conformation in these structures. Hence, different protein conformations will generate geometric alterations of the bound polyelectrolyte backbone, affording different emissions from the bound probe. Conformation-sensitive probes thus provide a direct link between spectral signal and protein conformation. Finally, the probes also proved useful for ex vivo fluorescence imaging by multiphoton excitation.

Displaced calcium hydroxide paste causing inferior alveolar nerve paraesthesia: report of a case.

A patient presented with an intraoral red, painful, and hard swelling in the lower right jaw. Radiographs showed a 2 x 1 cm area of radiopaque material surrounding the apex of the second premolar. The material, according to the patient's dentist, was calcium hydroxide paste used as a temporary dressing material in the root canal. The patient developed paraesthesia in her lower lip probably due to a neurotoxic effect caused by calcium hydroxide. The foreign material was surgically excavated from the spongious bone, directly adjacent to the nerve, and the patient later regained her sensation in the lip. A histopathological analysis revealed necrosis, deposits of foreign bodies, and inflammatory cells and foreign-body giant cells. This report illustrates the toxicity and adjacent clinical symptoms of calcium hydroxide paste when displaced into bone tissue close to the alveolar inferior nerve. It also demonstrates the benefits of removing such displaced material before symptoms progress.