Self-assembled magnetic heterostructure of Co/DLC films.

In order to adapt to the quick and large amount of necessity in data flow for 5G cloud generation, it is necessary to develop a technology of warm storage device in market which takes a great balance between the reading/writing performance and the price per storage capacity. The technologies of warm storage devices are assumed to adopt phase change memory (PCM), resistive random access memory or magnetoresistive random access memory which have the highest possibilities to 5G structures and magnetic properties of Co on non-hydrogenated diamond like carbon (DLC)/Si(100) films and Co/DLC interface are investigated. The self-assembled magnetic heterostructure is firstly reported in hexagonal close packing Co layers perpendicular magnetic anisotropy (PMA) on Co carbide layers (in-plane) during Co deposited on DLC/Si(100). A PMA/in-plane magnetic heterostructure is expected to have the highest switching current to the energy barrier ratio of near 4 in previous report, which has great potential for developing warm memory devices. Based on these unique characteristics, we provide a novel design called magnetic anisotropy-phase change memory (Mani-PCM) which can impact the developing blueprint of memory. The working process of Mani-PCM includes in set, reset and read states as a universal PCM. This brand new technology is highly promising as warm memory devices including high reading/writing performance and economical price per storage capacity.

Evolution of Granular Structure and the Enhancement of Electron Field Emission Properties of Nanocrystalline and Ultrananocrystalline Diamond Films Due to Plasma Treatment Process.

The present work reports the plasma post treatment (ppt) process that instigates the evolution of granular structure of nanocrystalline diamond (NCD), consequently conducing the enhancement of the electron field emission (EFE) properties. The NCD films contain uniform and nanosized diamond grains (∼20 nm) with negligible thickness for grain boundaries that is distinctly different from the microstructure of ultrananocrystalline (UNCD) films with uniformly sized ultrananodiamond grains (∼5 nm) having relatively thick grain boundaries (∼0.1 nm). The turn-on of the electron field emission (EFE) process occurs at ( E0)NCD = 24.1 V/µm and ( E0)UNCD = 18.6 V/µm for the pristine NCD and UNCD materials, respectively. The granular structure of the starting diamond films largely influenced the microstructure evolution behavior and EFE properties of the materials subject to plasma annealing. The CH4/(Ar-H2) ppt-process leads to formation of a hybrid granular structured diamond (HiDNCD and HiDUNCD) via isotropic conjoining of nanosized diamond grains, whereas the CH4/N2 ppt-process leads to the formation of acicular granular structured diamond films (NNCD and NUNCD) via inducing aeolotropic growth of nanodiamond grains. While both of the HiDNCD and HiDUNCD films contain hybrid granular structure, the HiDUNCD films contain a larger proportion of nanographite phase and result in improved EFE properties, viz. ( E0)HiD-UNCD = 7.7 V/µm and ( E0)HiD-NCD = 12.3 V/µm. In contrast, when the films were CH4/N2 ppt-processed, the acicular diamond grains were formed for NUNCD and NNCD films; however, carbon nanoclusters attached to the diamond grains of NNCD films and the nanographitic layers encasing diamond cores are not crystallized very well, as compared with NUNCD films. Therefore, the NNCD films exhibit slightly inferior EFE properties than the NUNCD films, viz. ( E0)N-UNCD = 5.3 V/µm and ( E0)N-NCD = 11.8 V/µm. The difference in EFE properties for ppt-processed NCD and UNCD films corresponds to the dissimilar granular structure evolution behavior in these films that is, in turn, due to the distinct different microstructure of the pristine NCD and UNCD films.

Applying DDX3X Biomarker to Discriminate Atypical from Benign Meningiomas in Tissue Microarray.

Patients with atypical meningiomas have a higher recurrence rate and poorer prognosis than patients with benign meningeal tumors. However, differentiating atypical from benign meningiomas based on fragmented specimens from brain tumor biopsy is complicated. We tested the association of DDX3X cytoplasmic expression and World Health Organization grading system in various subtypes of meningiomas. In our study, DDX3X expression was evaluated immunohistochemically in 10 non-neoplastic brain tissues and 71 meningiomas. The immunostaining scores were calculated as the product of cytoplasmic DDX3X intensity and the percentage of positively stained cells. Our results revealed most of the non-neoplastic brain tissues were immunonegative for DDX3X. The average DDX3X immunostaining score was significantly higher in meningiomas than non-neoplastic brain tissues and significantly higher in atypical meningiomas than in various subtypes of benign meningiomas. In conclusion, DDX3X immunohistochemistry combined with hematoxylin and eosin staining may help differentiate atypical meningiomas from benign meningeal tumors.

A numerical investigation of the effect of surface wettability on the boiling curve.

Surface wettability is recognized as playing an important role in pool boiling and the corresponding heat transfer curve. In this work, a systematic study of pool boiling heat transfer on smooth surfaces of varying wettability (contact angle range of 5° - 180°) has been conducted and reported. Based on numerical simulations, boiling curves are calculated and boiling dynamics in each regime are studied using a volume-of-fluid method with contact angle model. The calculated trends in critical heat flux and Leidenfrost point as functions of surface wettability are obtained and compared with prior experimental and theoretical predictions, giving good agreement. For the first time, the effect of contact angle on the complete boiling curve is shown. It is demonstrated that the simulation methodology can be used for studying pool boiling and related dynamics and providing more physical insights.

Nrf2 Expressions Correlate with WHO Grades in Gliomas and Meningiomas.

BACKGROUND: Nuclear factor erythroid 2-related factor 2 (NFE2L2, also known as Nrf2) is associated with cellular progression and chemotherapeutic resistance in some human cancers. We tested the relationship between Nrf2 expression and survival of patients with primary brain tumors (PBTs). METHODS: In order to realize Nrf2 protein expression in gliomas, Western blot analysis was performed in normal brain tissue and U87MG, LN229, GBM8401 and U118MG glioma cell lines protein lysates. Then, U87MG, LN229, and GBM8401 mRNA were applied to performed quantitative RT-PCR for detect Nrf2 gene expression in glioma cell lines. At last, immunohistochemical analysis was used to determine the expression of Nrf2 in samples from 178 PBTs and 10 non-neoplastic brain tissues. RESULTS: In these included in vitro studies, both Nrf2 protein and mRNA expression in all human glioma cell lines were higher than normal brain tissue. Similarly, on the viewpoint of immunohistochemistry, Nrf2 expression in gliomas were positively correlated with World Health Organization (WHO) grades. Additionally, compared with the expression of Nrf2 in non-neoplastic brain tissue, expression in meningiomas was of a stronger intensity and was present in a higher percentage of cells. Furthermore, scores were significantly higher in WHO grade II than in WHO grade I meningiomas. Finally, overall survival tended to be shorter in patients whose PBTs had higher expression of Nrf2, although the correlation was not statistically significant. CONCLUSIONS: Nrf2 overexpression positively correlated with WHO grade in gliomas and meningiomas. On the other hand, Nrf2 immunohistochemical stain could help pathologists to differentiate atypical meningiomas from benign tumors. Therefore, Nrf2 expression may be a useful biomarker to predict WHO grade and cellular behavior of PBTs.

Concurrent improvement in biocompatibility and bioinertness of diamond-like carbon films with nitrogen doping.

The surfaces of implantable biomaterials improving biocompatibility and bioinertness are critical for new application of bioimplantable devices. Diamond-like carbon (DLC) film is a promising biomaterial with use for coating bioimplantable devices because of its good biocompatibility, bioinertness, and mechanical properties. In this study, concurrent improvement in biocompatibility and bioinertness of DLC films has been achieved using N-incorporation technique. The N doping degree was found to play an important role in affecting the biocompatibility and bioinertness of N-doped DLC films. The results indicated that the N-doped DLC films deposited at N(2) concentration of 5% could help to create suitable condition of surface/structure/adhesion combination of DLC films in the both affinity of the L929 mouse fibroblasts and electrochemical inertness in the Hank's balanced salt solutions (simulating human body fluids). N doping supports the attachment and proliferation of cells and prevents the permeation of electrolyte solutions, thereby simultaneity improved the biocompatibility and bioinertness of DLC films. This finding is useful for the fabrication and encapsulation of in vivo devices without induced immune response in the human body.

Synthesis of highly transparent ultrananocrystalline diamond films from a low-pressure, low-temperature focused microwave plasma jet.

This paper describes a new low-temperature process underlying the synthesis of highly transparent ultrananocrystalline diamond [UNCD] films by low-pressure and unheated microwave plasma jet-enhanced chemical vapor deposition with Ar-1%CH4-10%H2 gas chemistry. The unique low-pressure/low-temperature [LPLT] plasma jet-enhanced growth even with added H2 and unheated substrates yields UNCD films similar to those prepared by plasma-enhanced growth without addition of H2 and heating procedure. This is due to the focused plasma jet which effectively compensated for the sluggish kinetics associated with LPLT growth. The effects of pressure on UNCD film synthesis from the microwave plasma jet were systematically investigated. The results indicated that the substrate temperature, grain size, surface roughness, and sp3 carbon content in the films decreased with decreasing pressure. The reason is due to the great reduction of Hα emission to lower the etching of sp2 carbon phase, resulting from the increase of mean free path with decreasing pressure. We have demonstrated that the transition from nanocrystalline (80 nm) to ultrananocrystalline (3 to 5 nm) diamond films grown via microwave Ar-1%CH4-10%H2 plasma jets could be controlled by changing the pressure from 100 to 30 Torr. The 250-nm-thick UNCD film was synthesized on glass substrates (glass transition temperature [Tg] 557°C) using the unique LPLT (30 Torr/460°C) microwave plasma jet, which produced UNCD films with a high sp3 carbon content (95.65%) and offered high optical transmittance (approximately 86% at 700 nm).

A wireless sensor enabled by wireless power.

Through harvesting energy by wireless charging and delivering data by wireless communication, this study proposes the concept of a wireless sensor enabled by wireless power (WPWS) and reports the fabrication of a prototype for functional tests. One WPWS node consists of wireless power module and sensor module with different chip-type sensors. Its main feature is the dual antenna structure. Following RFID system architecture, a power harvesting antenna was designed to gather power from a standard reader working in the 915 MHz band. Referring to the Modbus protocol, the other wireless communication antenna was integrated on a node to send sensor data in parallel. The dual antenna structure integrates both the advantages of an RFID system and a wireless sensor. Using a standard UHF RFID reader, WPWS can be enabled in a distributed area with a diameter up to 4 m. Working status is similar to that of a passive tag, except that a tag can only be queried statically, while the WPWS can send dynamic data from the sensors. The function is the same as a wireless sensor node. Different WPWSs equipped with temperature and humidity, optical and airflow velocity sensors are tested in this study. All sensors can send back detection data within 8 s. The accuracy is within 8% deviation compared with laboratory equipment. A wireless sensor network enabled by wireless power should be a totally wireless sensor network using WPWS. However, distributed WPWSs only can form a star topology, the simplest topology for constructing a sensor network. Because of shielding effects, it is difficult to apply other complex topologies. Despite this limitation, WPWS still can be used to extend sensor network applications in hazardous environments. Further research is needed to improve WPWS to realize a totally wireless sensor network.