Reconfigurable Intelligent Surface-Aided Wireless Power Transfer Systems: Analysis and Implementation

Reconfigurable intelligent surface (RIS) is a promising technology for RF wireless power transfer (WPT) as it is capable of beamforming and beam focusing without using active and power-hungry components. In this paper, we propose a multi-tile RIS beam scanning (MTBS) algorithm for powering up internet-of-things (IoT) devices. Considering the hardware limitations of the IoT devices, the proposed algorithm requires only power information to enable the beam focusing capability of the RIS. Specifically, we first divide the RIS into smaller RIS tiles. Then, all RIS tiles and the phased array transmitter are iteratively scanned and optimized to maximize the receive power. We elaborately analyze the proposed algorithm and build a simulator to verify it. Furthermore, we have built a real-life testbed of RIS-aided WPT systems to validate the algorithm. The experimental results show that the proposed MTBS algorithm can properly control the transmission phase of the transmitter and the reflection phase of the RIS to focus the power at the receiver. Consequently, after executing the algorithm, about 20 dB improvement of the receive power is achieved compared to the case that all unit cells of the RIS are in OFF state. By experiments, we confirm that the RIS with the MTBS algorithm can greatly enhance the power transfer efficiency

Concurrent Multilocular Cystic Renal Cell Carcinoma and Leiomyoma in the Same Kidney: Previously Unreported Association

We present an unusual case of concurrent occurrence of a multilocular cystic renal cell carcinoma and a leiomyoma in the same kidney of a patient with no evident clinical symptoms. A 38-year-old man was found incidentally to have a cystic right renal mass on computed tomography. Laparoscopic radical nephrectomy was performed under a preoperative diagnosis of cystic renal cell carcinoma. Histology revealed a multilocular cystic renal cell carcinoma and a leiomyoma. This is the first report of this kind of presentation

Neuroprotective Activity of Sibjeondaebo-tang on Aβ Peptide-Induced Damages

Background. Sibjeondaebo-tang (SJDBT) has been used to treat diverse disorders including neuropsychiatric disabilities in traditional Korean medicine. Objective. The present study aims to investigate the potential effects of SJDBT on neuroprotection against Aβ peptide-induced damage using in vitro culture and in vivo rat brain systems. Materials and Methods. PC12 cell viability was analyzed by MTT assay, and neurite arborizations and caspase 3 protein signals in cultured PC12 cells and in vivo cortical neurons were analyzed by immunofluorescence staining. Phospho-Erk1/2 protein was analyzed by immunofluorescence staining and western blot analysis. Results. In PC12 cells, atrophied cell body and reduced neurite extension by Aβ treatment were recovered by SJDBT treatment. Caspase 3 protein signals were increased in Aβ-treated PC12 cells, but SJDBT treatment decreased apoptotic cell death. Caspase 3 activation in cortical neurons, which was induced similarly by Aβ treatment, was reduced by SJDBT treatment. Furthermore, phospho-Erk1/2 protein levels, which had been decreased by Aβ treatment, were elevated in the cortical neurons by SJDBT treatment. Conclusion. These data show that SJDBT may play a role in protecting from damages induced by Aβ in neuronal tissue and further suggest that SJDBT can be explored as the potential therapeutic target for AD treatments in human

Enhanced cytotoxic effect of radiation and temozolomide in malignant glioma cells: targeting PI3K-AKT-mTOR signaling, HSP90 and histone deacetylases

BACKGROUND: Despite aggressive treatment with radiation therapy and concurrent adjuvant temozolomide (TMZ), glioblastoma multiform (GBM) still has a dismal prognosis. We aimed to identify strategies to improve the therapeutic outcome of combined radiotherapy and TMZ in GBM by targeting pro-survival signaling from the epidermal growth factor receptor (EGFR). METHODS: Glioma cell lines U251, T98G were used. Colony formation, DNA damage repair, mode of cell death, invasion, migration and vasculogenic mimicry as well as protein expression were determined. RESULTS: U251 cells showing a low level of methyl guanine transferase (MGMT) were highly responsive to the radiosensitizing effect of TMZ compared to T98G cells having a high level of MGMT. Treatment with a dual inhibitor of Class I PI3K/mTOR, PI103; a HSP90 inhibitor, 17-DMAG; or a HDAC inhibitor, LBH589, further increased the cytotoxic effect of radiation therapy plus TMZ in U251 cells than in T98G cells. However, treatment with a mTOR inhibitor, rapamycin, did not discernibly potentiate the radiosensitizing effect of TMZ in either cell line. The mechanism of enhanced radiosensitizing effects of TMZ was multifactorial, involving impaired DNA damage repair, induction of autophagy or apoptosis, and reversion of EMT (epithelial-mesenchymal transition). CONCLUSIONS: Our results suggest possible strategies for counteracting the pro-survival signaling from EGFR to improve the therapeutic outcome of combined radiotherapy and TMZ for high-grade gliomas

Demonstration of P-Type Stack-Channel Ternary Logic Device Using Scalable Dntt Patterning Process

A p-type ternary logic device with a stack-channel structure is demonstrated using an organic p-type semiconductor, dinaphtho[2,3-b:2\u27,3\u27-f]thieno[3,2-b]thiophene (DNTT). A photolithography-based patterning process is developed to fabricate scaled electronic devices with complex organic semiconductor channel structures. Two layers of thin DNTT with a separation layer are fabricated via the low-temperature deposition process, and for the first time, p-type ternary logic switching characteristics exhibiting zero differential conductance in the intermediate current state are demonstrated. The stability of the DNTT stack-channel ternary logic switch device is confirmed by implementing a resistive-load ternary logic inverter circuit