Dynamic beam steering for wireless optical power transfer in IoT applications.

The alignment of a receiver with a pencil beam in a wireless optical power transfer (WOPT) system employing a resonance beam charging (RBC) technology limits the establishment of a resonance cavity. Accurate tracking necessitates precise and dependable monitoring, which requires the exact placement of transmitting and receiving devices. Herein, we present a concept of a two-dimensional (2D) beam steering mechanism for RBC-based WOPT systems utilizing dispersed laser beams. The proposed approach allows a significant improvement, including reduction of scanning times and minimization of errors, in relation to conventional pencil-beam-based systems. Experimental results reveal 14% faster acquisition time efficiency, an 18% improvement in pointing accuracy, and a 24% enhancement in tracking accuracy. These results establish the prerequisites for the implementation of dispersed beam steering in the RBC-based WOPT system. This capability empowers the system to charge movable devices and Internet of Things devices consistently in smart factories.

Simple and cost-effective way to make mobile antibiotic cement spacer: hand-made silicone mold.

BACKGROUND: Two-stage exchange arthroplasty is considered the most common approach for the management of prosthetic joint infections. There has been plentiful evidence to support the superiority of the mobile spacers over the static ones. Unfortunately, articulating options are not available in our low-resource environment, which motivated us to come up with an affordable way to create a mobile cement spacer. After experimenting with a variety of materials and producing methods, we realized that silicone is a favorable material for mold building and established a simple process of making a handmade silicone mold. We demonstrate the clinical outcomes of three prosthetic joint infections by using these spacers in the hope of spreading the idea to our colleagues who work in the circumstances of a developing country. Construction of the spacer molds: The molds, consisting of two parts, were shaped by using high viscosity addition silicone (elite HD+ putty soft, Zhermack SpA, Italy) as material, and previously removed implants as template. They were sterilized using ethylene oxide treatment before being ready for casting antibiotic-loaded bone cement spacer. CASE REPORT: Three cases of prosthetic infection were treated with two-stage revision, using antibiotic-impregnated cement spacer cast in hand-made silicone molds. We sought to determine intraoperative complications, postoperative range of motion, and functional scores. All the patients were regularly followed up to identify fractures or dislocation of the spacer, and reinfection. RESULTS: At the end of the follow-up, all three patients had the infection eradicated. The three patients could sit comfortably with bent knees, walk with partial weight-bearing, and achieve 75-80 degrees of knee flexion in the first week after surgery. Follow-up X-rays revealed no fractures or dislocation in any of the spacers. CONCLUSION: Silicone molds offer a simple and cost-effective alternative to costly commercial products in producing articulating spacers. Treating infected joints arthroplasty with these spacers allows for early motion and partial weight bearing and improves patient satisfaction and life quality before reimplantation without significant complications.

Machine Learning Model for Identifying Antioxidant Proteins Using Features Calculated from Primary Sequences.

Antioxidant proteins are involved importantly in many aspects of cellular life activities. They protect the cell and DNA from oxidative substances (such as peroxide, nitric oxide, oxygen-free radicals, etc.) which are known as reactive oxygen species (ROS). Free radical generation and antioxidant defenses are opposing factors in the human body and the balance between them is necessary to maintain a healthy body. An unhealthy routine or the degeneration of age can break the balance, leading to more ROS than antioxidants, causing damage to health. In general, the antioxidant mechanism is the combination of antioxidant molecules and ROS in a one-electron reaction. Creating computational models to promptly identify antioxidant candidates is essential in supporting antioxidant detection experiments in the laboratory. In this study, we proposed a machine learning-based model for this prediction purpose from a benchmark set of sequencing data. The experiments were conducted by using 10-fold cross-validation on the training process and validated by three different independent datasets. Different machine learning and deep learning algorithms have been evaluated on an optimal set of sequence features. Among them, Random Forest has been identified as the best model to identify antioxidant proteins with the highest performance. Our optimal model achieved high accuracy of 84.6%, as well as a balance in sensitivity (81.5%) and specificity (85.1%) for antioxidant protein identification on the training dataset. The performance results from different independent datasets also showed the significance in our model compared to previously published works on antioxidant protein identification.

Unimolecular Logic Gate with Classical Input by Single Gold Atoms.

By a combination of solution and on-surface chemistry, we synthesized an asymmetric starphene molecule with two long anthracenyl input branches and a short naphthyl output branch on the Au(111) surface. Starting from this molecule, we could demonstrate the working principle of a single molecule NAND logic gate by selectively contacting single gold atoms by atomic manipulation to the longer branches of the molecule. The logical input "1" ("0") is defined by the interaction (noninteraction) of a gold atom with one of the input branches. The output is measured by scanning tunneling spectroscopy following the shift in energy of the electronic tunneling resonances at the end of the short branch of the molecule.

Total synthesis of (-)-epimyrtine by a gold-catalyzed hydroamination approach.

A new approach to the total synthesis of (-)-epimyrtine has been developed from D-alanine. The key step to access the enantiopure pyridone intermediate was achieved by a gold-mediated cyclization. Finally, various transformations afforded the natural product in a few steps and good overall yield.

UV-protectant metabolites from lichens and their symbiotic partners.

Lichens are structurally complex symbiotic organisms that are exposed to a wide variety of external conditions (extreme temperatures, desiccation, UV radiation, etc.). These poikilohydric organisms have developed various mechanisms of photoprotection, such as light scattering, radiation screening, thermal dissipation, activation of antioxidant defense and macromolecules and membrane repair. These unique organisms produce a vast array of compounds, with more than 1000 secondary metabolites known. An important protective mechanism of lichens is the production of UV screening compounds, such as phenolic compounds (depsidones, depsides, diphenyl ethers), anthraquinones, xanthones or shikimic acid derivatives (calycin, mycosporines, scytonemin). Due to the harmful effects of the UVA wavelengths of sunlight, the search for new sunscreens remains important. We herein propose a review that focuses on the UV protectants from lichens and their symbiotic partners (lichenized fungi, green alga, cyanobacteria). In fact, lichens produce unique and/or efficient UV filters such as depsidones (lobaric acid, pannarin, etc.), depsides (atranorin, gyrophoric acid, etc.), diphenyl ethers (epiphorellic acids, buellin), bisxanthones (secalonic acids, etc.), mycosporines and MAAs, scytonemin along with classical pigments (melanin, carotenoids). We propose to classify these compounds with regard to their chemical structures and review the physicochemical properties that act as UV filters. While the most abundant lichen polyfunctionalized aromatic compounds, belonging to orsellinic derivatives, are UVB screens, these organisms produce strong UVA filters, e.g., calycin (pulvinic acid derivatives), bisxanthones (secalonic acids), scytonemin or mycosporines and MAAs with the latter ones exhibiting attractive properties as photoprotectants.

Gold-mediated synthesis and functionalization of chiral halopyridones.

A rapid and efficient one-step halopyridone synthesis has been developed based on gold-catalyzed cyclization of ß-amino-ynone intermediates and halodeauration process.