An Efficient Catalyst of CuPt/TiO2 for Photocatalytic Direct Dehydrogenation of Methanol to Methyl Formate at Ambient Temperature

To obtain high methanol conversion at high methyl formate (MF) selectivity by the thermal reaction of direct dehydrogenation of methanol is a challenging issue due to the thermodynamic restriction. Herein,...

Research progress in the estimation of postmortem interval (PMI) using non-coding RNA (ncRNA) markers

Postmortem interval (PMI) estimation has always been a crucial focus and challenging issue in forensic pathology. In recent years, specific RNA molecules and their variation have been used worldwide to estimate PMI. In this review, we summarize the methods used to detect non-coding RNAs (ncRNAs) for PMI estimation based on the literature, show the existing problems and development trends, and provide technical references for relevant studies and estimation practices.

The power of ancient stones: Protecting children in Greek Sicily

The paper focuses on the occurrence of Castelluccian (Early Bronze Age) pebble pendants in sub-adult tombs found in Greek, but also indigenous sites in Sicily from 8th century BC onwards. These pebble-shaped pendants are made of various materials, especially alabaster and translucent stones. They are usually unearthed with shells, perhaps to form a single ornament, in close bond with selected people. The occurrence in archaic infant burials, both in Greek and indigenous contexts, without being documented meanwhile, brings up a challenging issue: we can argue that these items, discovered accidentally in very ancient tombs, were considered to be old and therefore deemed particularly valuable also due to the intrinsic properties of the stones, being shiny and translucent. As a consequence (by drawing inspiration from native women's ancient knowledge?) they were probably conveyed a new meaning and turned into apotropaic amulets in order to protect children from diseases during life, and from perils in afterlife.

Rapid Prototyping For Series of Tasks in Atypical Environment: Robotic System With Reliable Program-Based and Flexible Learning-Based Approaches

We propose a novel robotic system that combines both a reliable programming-based approach and a highly generalizable learning-based approach. How to design and implement a series of tasks in an atypical environment is a challenging issue. If all tasks are implemented using a programming-based approach, the development costs will be huge. However, if a learning-based approach is used, reliability is an issue. In this paper, we propose novel design guidelines that focus on the respective advantages of programming-based and learning-based approaches and select them so that they complement each other. We use a program-based approach for actions that are dynamic and require safety and reliability and a learning-based approach for actions that have a limited working area and are difficult to achieve with a program. Our learning approach can easily and rapidly accomplish a series of tasks consisting of various motions because it does not require a computational model of an object to be designed in advance. We demonstrate a series of tasks in which randomly arranged parts are assembled using an actual robot.

Compensation of Data Loss Using ARMAX Model in State Estimation for Control and Communication Systems Applications

Compensation of data loss in the state estimation plays an indispensable role in efficient and stable control and communication systems. However, accurate compensation of data loss in the state estimation is extremely challenging issue. To cater this challenging issue, two techniques such as the open-loop Kalman filter and the compensating closed-loop Kalman filter have emerged. The closed-loop technique compensates for the missing data using the autoregressive model. However, the autoregressive model used only past measurements for data loss compensation. Considering only one parameter, i.e., the past measurements, is insufficient and leads to inaccurate state estimation. Thus, in this work, autoregressive moving average with exogenous inputs model considers three parameters, i.e., the past measurements, the input signal, and the sensor noise, simultaneously to compensate data loss in state estimation. To endorse the effectiveness and applicability of the proposed model, a standard mass-spring-damper is employed in the case study. Simulation results show that the proposed model outperforms the existing autoregressive models in terms of performance parameters.

Tongue reconstruction in cancer patients: current state of the problem (literature review)

Tongue repair after radical surgical removal of malignant tumors with subsequent rehabilitation of patients and their return to normal life and work has been a challenging issue for decades.This review aims to give an up to date summary of existing literature on different methods of tongue repair in cancer patients depending on the type of defect. We describe advantages and disadvantages of local and regional free autologous grafts.

Computational analyses of Fe-Chelation by thiofavipiravir

Existence of iron (Fe) is important for cells of living systems; however, its level of magnitude for those patients infected by novel coronavirus disease (COVID-19) is still a challenging issue. Therefore, such mechanism of function was investigated in this work by assistance of thiofavipiravir (TFav) compounds generated by the well-known favipiravir (Fav) drug used for medication of COVID-19 patents. To this aim, sulfur-substitutions of oxygen atoms of Fav were done and the obtained parent structures were prepared for participating in Fe-chelation function. The results indicated that the modes were suitable for running such Fe-chelation processes, in which favorability and strength the models were ranged in this order: 1O2S-Fe > 1S2S-Fe > 1O2O-Fe > 1S2O-Fe. As a consequence, such idea of sulfur-substitution of Fav drug for more appropriate favorability of participating in Fe-chelation process was sensed by results of this work proposing 1O2S compound as the most favorable one for doing the function. Hence, information about capability of TFav compounds for participating in Fe-chelation processes were provided in this work regarding the challenging issue of Fe-chelation in medication of COVID-19 patients. All results of this work were obtained by performing computations using the density functional theory (DFT) approach

Cardiovascular considerations of Remdesivir and Favipiravir in the treatment of COVID-19

: After the outbreak of COVID-19, many novel drugs have been introduced to improve patients’ condition. Remdesivir and Favipiravir are among the most common drugs used against SARS-CoV-2. Although promising, cardiovascular side effects of these drugs should be considered by physicians and nurses. In this study, we searched databases for assessing the cardiovascular side effects of Remdesivir and Favipiravir. It seems that despite the beneficial effects of these drugs, due to the cardiovascular complications of COVID-19 and cardiovascular side effects of these drugs which can overlap with each other, the use of these drugs can be a challenging issue in the cardiovascular practice.

Potential of medicinal plants in management of diabetes: An updates

Phytochemical means plant derived chemicals they are defined as bioactive nutrient present in plant in fruits, vegetables, grains, and other part of plants that may provide advantageous health benefits across basic nourishment. Medicinal plants are used in the treatment of various illness due to the presence of therapeutically important phytochemicals. Sometimes in patients with diabetes mellitus, the levels of antioxidant parameters are found to decrease, hence in many studies phytochemicals are suggested to improve the insulin sensitivity. Some phytocompounds such as flavonoids, prophenyl phenols, are also found effective in the complications of diabetes. The major challenging issue in diabetes management is the obstruction of various complications that remain the main cause of diabetes-related mortality. This review mainly focuses on the relationship between diabetes mellitus and preventive roles of various phytochemicals on diabetes.

Mechanical Properties and Structural Analysis of Coatings and Engineered Surfaces

The performance improvement in engineering components during operation is a challenging issue and surface engineering methods have been attracting considerable interest in both research and industrial fields [...]