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An origami sonic barrier composed of cylindrical inclusions attached onto an origami sheet is proposed. The idea allows for tunable sound blocking properties for application in attenuating complex traffic noise spectra. Folding of the underlying origami sheet transforms the periodicity of the inclusions between different Bravais lattices, viz. between a square and a hexagonal lattice, and such significant lattice re-configuration leads to drastic tuning of dispersion characteristics. The wave tuning capabilities are corroborated via performing theoretical and numerical investigations using a plane wave expansion method and an acoustic simulation package of COMSOL, while experiments are performed on a one-seventh scaled-down model of origami sonic barrier to demonstrate the lattice re-configuration between different Bravais lattices and the associated bandgap adaptability. Good sound blocking performance in the frequency range of traffic noise spectra combined with less efforts, required for actuating one-degree of freedom folding mechanism, makes the origami sonic barrier a potential candidate for mitigating complex traffic noise. [ABSTRACT FROM AUTHOR]

Intrinsic localized modes (ILMs) are concentrations of vibrational energy in periodic systems/ lattices due to the combined influences of nonlinearity and discreteness. Moreover, ILMs can move within the system and may strongly interact with an impurity, such as a stiffness change, mass variation, etc. Numerous scientific fields have uncovered examples and evidence of ILMs, motivating a multidisciplinary pursuit to rigorously understand the underlying principles. In spite of the diverse technical studies, a characterization of ILM interaction behaviors with multiple impurities in dissipative lattices remains outstanding. The insights on such behaviors may be broadly useful when dynamic measurements are the only accessible features of the periodic system. For instance, one may guide an ILM within the lattice using a deliberately applied and steered impurity and harness the observed interaction behaviors with a second, static (immovable) impurity/defect to identify how the underlying lattice is different at the second, defected site, whether or not one knew the position of the defect a priori. In this spirit, this research studies, analyzes, and characterizes the interaction types amongst an ILM and multiple impurities, and devises a method to identify a static defect impurity using quantitatively and qualitatively distinct interaction phenomena. The method is found to be robust to moderate levels of lattice stiffness heterogeneity and is applicable to monitor various property changes that represent impurities. Finally, experimental studies verify that ILMs interact with multiple impurities in unique ways such that defect features may be effectively identified. [ABSTRACT FROM AUTHOR]

The Internet of Things (IoT) concept is expected to evolve the interest of each industry, medicine, and others. The main forces behind the huge data gathering were the IoT devices built into the sensor. One of the biggest challenges has been the maintenance of those huge data sets. A massive IoT (mIoT) refers to the continuous collection of huge quantities of data with sensors. Therefore, self-adaptive algorithms based on AI are required to aggregate, evaluate and effectively understand all program objects. It is imperative to control the energy carefully due to the increase in large datasets and power-hungry IoT gadgets. It is critical to combine mIoT using AI-based approaches to fairly distribute power levels to small portable devices. The connection between the lifetime of the mIoT and the information flow found that as information rates increase, more energy is lost, reducing the service life of mIoT networks. With more sensor nodes, the power would be appropriately distributed across the transverse layers. By analyzing key characteristics and data sets, this research suggests a new Improved Random Energy Optimization Algorithm (IIRBEOA) for mIoT systems to address these issues. According to an experimental survey, the proposed IRBEOA exceeds its Baseline rival in terms of practical control and implementation of energy.

Background: Endodontically treated teeth have increased susceptibility to fracture. To promote the fracture resistance, reinforcing the endodontically treated teeth is of utmost importance. An ideal restoration or core is necessary to build up the coronal portion of the tooth to an ideal anatomic form before the full coverage placement. Aims: Compare the fracture resistance of Nayyar Cores of amalgam, Zirconomer, and Para Core with natural teeth . Methods: This study compared the fracture resistance of coronal-radicular restorations made from three different restorative materials. Sixty human mandibular molars were selected, 45 of which were decoronated and root treated – 15 of these molars restored with amalgam, 15 with Zirconomer, and 15 using Para Core. The 15 natural teeth used as a control group. All the teeth were mounted in acrylic and subjected to compressive loading to failure on a universal testing machine. The force required to fracture each core specimen was recorded. Results: The data of the study were statistically analyzed by ANOVA test and Tukey post hoc test. The results of the study showed that natural teeth as having the highest fracture resistance values, followed by Para Core, amalgam, and Zirconomer. The differences among all groups were significant. Conclusion: Within the limitations of this study, natural teeth showed higher fracture resistance to that of the Para Core, amalgam, and Zirconomer. Among the 3 Nayyar cores, Para Core has higher fracture resistance.

Background and Aims: The purpose of this study was to compare the microleakage of conventional crowns and endocrowns using confocal laser scanning electron microscope. Materials and Methods: Thirty extracted human permanent mandibular molars were collected and sectioned parallel to the occlusal surface at 2 mm above the CEJ to deroof the pulp chamber. Endodontic treatment was performed. The gutta-percha was removed 1 mm below the orifice of each canal, and flowable resin composite was filled in the canals up to the level of the pulp chamber. Samples were then randomly divided into two groups with 15 teeth each according to the type of post endodontic restoration given – Group 1: conventional crowns and Group 2: endocrowns. In Group (1), teeth were restored with composite cores, wide circumferential deep chamfer margin (0.8 mm) was prepared at the CEJ and 2 mm from the occlusal surface, 1.5 mm were cut from the axial walls. In Group (2), preparation was performed by making a circular butt margin with a central retention cavity with rounded internal line angles. Impressions were made, crowns were fabricated, and cementation was done, followed by thermocycling. The specimens were coated with varnish up to 1 mm from the crown margins, placed in Rhodamine B dye for 60 h, rinsed thoroughly for 30 s, sectioned with hard tissue microtome and examined for microleakage. Statistical Analysis: Statistical analysis was accomplished with the Student t-test, and significance was predetermined at P < 0.05. Results: In this study, endocrowns (6.158) showed significantly low microleakage compared with conventional crowns (14.052). Conclusion: Endocrowns showed significantly lower microleakage.

With the development of more sensitive screening tools, malignancies are being diagnosed at an earlier stage, resulting in earlier intervention and longer survival times. As a consequence, the long-term complications of cancer therapy are increasing in incidence, particularly second primary cancers from radiation therapy. Bladder and colorectal cancers are the most commonly reported malignancies secondary to radiation therapy for prostate cancer. We present the case of a 78-year-old patient with a remote history of prostate adenocarcinoma, status post brachytherapy, who subsequently developed both prostate sarcoma and prostate squamous cell carcinoma secondary to the prior treatment. Because his cancer was metastatic, he was not a candidate for surgery and was treated with chemotherapy and palliative radiation., (Copyright © 2021 Baylor University Medical Center.)

Lactate, or lactic acid, is an end-product of anaerobic metabolism. The build-up of lactate in the body is commonly due to type A lactic acidosis, resulting from an inability to meet the body's oxygen delivery demands. When lactic acidosis persists, other causes need to be ruled out. Here, we describe the case of a 63-year-old female who initially presented with hypoglycemia and was found to have significant lactic acidosis. Her blood sugar levels improved with dextrose supplementation; however, lactic acidosis persisted despite fluid hydration and empiric antibiotics. After excluding other causes of lactic acidosis, she was started on intravenous thiamine due to suspicion of thiamine deficiency secondary to poor nutrition. Lactic acid levels improved drastically after starting thiamine supplementation. Thiamine is a water-soluble vitamin that plays an essential role as a cofactor in several biochemical reactions. Thiamine deficiency is a rare, underdiagnosed cause of type B lactic acidosis, with early diagnosis and intervention playing crucial roles in preventing severe cardiac and neurological impairment., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2021, Thota et al.)

A commonly seen phenomenon in the hospital and critical care setting is anaphylaxis. This acute systemic inflammatory reaction can lead to anaphylactic shock in severe cases and potentially be fatal. The role of platelets in anaphylactic reactions is not well established; however, platelets, among other mediators such as platelet-activating factor, have been shown to promote a prothrombotic state shortly after an acute hypersensitivity reaction. In addition, the aggregation of platelets promoted by platelet-activating factor and other mediators can also lead to thrombocytopenia. We present a case of a 57-year-old woman who developed severe anaphylaxis while receiving chemotherapy with paclitaxel suspended in Cremophor, a well-known allergen. She was profoundly thrombocytopenic following the reaction and was treated with therapeutic anticoagulation, with no thrombus formation., (Copyright © 2021 Baylor University Medical Center.)