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1.
ACS Appl Mater Interfaces ; 16(3): 3509-3519, 2024 Jan 24.
Article in English | MEDLINE | ID: mdl-38225735

ABSTRACT

Not all encapsulation techniques are universally apt for every type of phase change material (PCM), highlighting the imperative for methodological precision. This study addresses the challenges of microencapsulated PCM (MEPCM) arising from the immiscible pairing of α-Al2O3 nanoparticles with Sn microparticles. The high-speed impact blending (HIB) dry synthesis technique is employed, facilitating large-volume production of Sn@α-Al2O3 MEPCMs. The resulting MEPCMs not only seamlessly endure 100 cycles of melting-solidification but also, with the strategic incorporation of a glass frit, exhibit remarkable thermal durability, withstanding up to 1000 melting-solidification cycles. Even under ultrafast thermal fluctuations, the α-Al2O3 shell remained resilient through 100 cycles. A marked reduction in supercooling is observed, which is attributed to the formation of SnO and SnO2 nanoparticles within the α-Al2O3 crystal lattice. The atomically resolved interface dynamics between SnO2 and α-Al2O3 play a pivotal role, lowering the energy barrier for Sn nuclei formation during solidification. This affects the accelerated Sn nucleation rate, effectively suppressing supercooling. Such insights offer a deeper understanding of the interplay between nanoscale crystal lattice imperfections and their implications for energy storage applications.

2.
Cerebellum ; 22(4): 680-697, 2023 Aug.
Article in English | MEDLINE | ID: mdl-35781778

ABSTRACT

This study aimed to investigate the effects of repetitive transcranial magnetic stimulation (rTMS) of the cerebellum on changes in motor performance during a series of repetitive ballistic-targeting tasks. Twenty-two healthy young adults (n = 12 in the active-rTMS group and n = 10 in the sham rTMS group) participated in this study. The participants sat on a chair in front of a monitor and fixed their right forearms to a manipulandum. They manipulated the handle with the flexion/extension of the wrist to move the bar on the monitor. Immediately after a beep sound was played, the participant moved the bar as quickly as possible to the target line. After the first 10 repetitions of the ballistic-targeting task, active or sham rTMS (1 Hz, 900 pulses) was applied to the right cerebellum. Subsequently, five sets of 100 repetitions of this task were conducted. Participants in the sham rTMS group showed improved reaction time, movement time, maximum velocity of movement, and targeting error after repetition. However, improvements were inhibited in the active-rTMS group. Low-frequency cerebellar rTMS may disrupt motor learning during repetitive ballistic-targeting tasks. This supports the hypothesis that the cerebellum contributes to motor learning and motor-error correction in ballistic-targeting movements.


Subject(s)
Movement , Transcranial Magnetic Stimulation , Young Adult , Humans , Cerebellum/physiology , Upper Extremity , Reaction Time
3.
ACS Omega ; 7(32): 28313-28323, 2022 Aug 16.
Article in English | MEDLINE | ID: mdl-35990461

ABSTRACT

Gallium has been considered for application in the thermal management of electronic equipment because of its high heat transfer ability and heat storage density. To address the issues of metal corrosion and leakage, a microencapsulation method, through which a stable corrosion-resistant ceramic shell can be formed from the liquid metal, is proposed. In this study, an optimized fabrication method for a microencapsulated phase change material (MEPCM) consisting of liquid-state Ga droplets, possessing high durability and heat storage density, is presented. A fabrication route comprising particle formation, hydrothermal treatment, and calcination is proposed. In particular, the thickness and crystal size of the GaOOH shell are controlled by changing the pH during hydrothermal treatment to produce a highly durable shell. The morphology and microstructure, phase composition, heat storage capacity, and durability of the prepared Ga-MEPCM are investigated. In addition, treatment conditions and the shell formation mechanism are analyzed. The results show that pH 9 is the most suitable shell-forming condition, at which the thickest Ga2O3 shell with the smallest crystal size can be produced, which is beneficial for ensuring durability. The MEPCM achieved 200 cycles without leakage and 300 cycles without shape deformation with a high heat storage density of 369.4 J·cm-3.

4.
Front Immunol ; 13: 770132, 2022.
Article in English | MEDLINE | ID: mdl-35154098

ABSTRACT

The quality of chimeric antigen receptor (CAR)-T cell products, namely, memory and exhaustion markers, affects the long-term functionality of CAR-T cells. We previously reported that piggyBac (PB) transposon-mediated CD19 CAR-T cells exhibit a memory-rich phenotype that is characterized by the high proportion of CD45RA+/C-C chemokine receptor type 7 (CCR7)+ T-cell fraction. To further investigate the favorable phenotype of PB-CD19 CAR-T cells, we generated PB-CD19 CAR-T cells from CD45RA+ and CD45RA- peripheral blood mononuclear cells (PBMCs) (RA+ CAR and RA- CAR, respectively), and compared their phenotypes and antitumor activity. RA+ CAR-T cells showed better transient gene transfer efficiency 24 h after transduction and superior expansion capacity after 14 days of culture than those shown by RA- CAR-T cells. RA+ CAR-T cells exhibited dominant CD8 expression, decreased expression of the exhaustion marker programmed cell death protein-1 (PD-1) and T-cell senescence marker CD57, and enriched naïve/stem cell memory fraction, which are associated with the longevity of CAR-T cells. Transcriptome analysis showed that canonical exhaustion markers were downregulated in RA+ CAR-T, even after antigen stimulation. Although antigen stimulation could increase CAR expression, leading to tonic CAR signaling and exhaustion, the expression of CAR molecules on cell surface after antigen stimulation in RA+ CAR-T cells was controlled at a relatively lower level than that in RA- CAR-T cells. In the in vivo stress test, RA+ CAR-T cells achieved prolonged tumor control with expansion of CAR-T cells compared with RA- CAR-T cells. CAR-T cells were not detected in the control or RA- CAR-T cells but RA+ CAR-T cells were expanded even after 50 days of treatment, as confirmed by sequential bone marrow aspiration. Our results suggest that PB-mediated RA+ CAR-T cells exhibit a memory-rich phenotype and superior antitumor function, thus CD45RA+ PBMCs might be considered an efficient starting material for PB-CAR-T cell manufacturing. This novel approach will be beneficial for effective treatment of B cell malignancies.


Subject(s)
Antigens, CD19/genetics , DNA Transposable Elements/genetics , Leukocyte Common Antigens/genetics , Leukocytes, Mononuclear/immunology , Receptors, Antigen, T-Cell/genetics , Receptors, Chimeric Antigen/genetics , Animals , Antigens, CD19/immunology , Cell Line, Tumor , Female , Humans , Immunotherapy, Adoptive/methods , Leukocyte Common Antigens/immunology , Mice , Mice, Inbred NOD , Phenotype , Precursor Cell Lymphoblastic Leukemia-Lymphoma , Receptors, Antigen, T-Cell/immunology , Receptors, Chimeric Antigen/immunology , T-Lymphocytes/immunology
5.
Front Pharmacol ; 11: 578955, 2020.
Article in English | MEDLINE | ID: mdl-33117171

ABSTRACT

Transient receptor potential ankyrin 1 (TRPA1) channel is an ion channel whose gating is controlled by agonists, such as allyl isothiocyanate (AITC), and temperature. Since TRPA1 is associated with various disease symptoms and chemotherapeutic side effects, it is a frequent target of drug development. To facilitate the screening of TRPA1 agonists and antagonists, this study aimed to develop a simple bioassay for TRPA1 activity. To this end, transgenic Chlamydomonas reinhardtii expressing human TRPA1 was constructed. The transformants exhibited positive phototaxis at high temperatures (≥20°C) but negative phototaxis at low temperatures (≤15°C); wild-type cells showed positive phototaxis at all temperatures examined. In the transgenic cells, negative phototaxis was inhibited by TRPA1 antagonists, such as HC030031, A-967079, and AP18, at low temperatures. Negative phototaxis was induced by TRPA1 agonists, such as icilin and AITC, at high temperatures. The effects of these agonists were blocked by TRPA1 antagonists. In wild-type cells, none of these substances had any effects on phototaxis. These results indicate that the action of TRPA1 agonists and antagonists can be readily assessed using the behavior of C. reinhardtii expressing human TRPA1 as an assessment tool.

6.
Front Psychiatry ; 6: 58, 2015.
Article in English | MEDLINE | ID: mdl-25954210

ABSTRACT

Seven male children with autism spectrum disorder (ASD), aged 8-12 years, attending special education classrooms for ASD and disabled children, were assigned to receive touch therapy. Their mothers were instructed to provide gentle touch in the massage style of the International Liddle Kidz Association. The mothers gave massages to their child for 20 min every day over a period of 3 months, followed by no massage for 4 months. To assess the biological effects of such touch therapy, saliva was collected before and 20 min after a single session of massage for 20 min from the children and mothers every 3 weeks during the massage period and every 4 weeks during the non-massage period, when they visited a community meeting room. Salivary oxytocin levels were measured using an enzyme immunoassay kit. During the period of massage therapy, the children and mothers exhibited higher oxytocin concentrations compared to those during the non-massage period. The changes in oxytocin levels before and after a single massage session were not significantly changed in children and mothers. The results suggested that the ASD children (massage receivers) and their mothers (massage givers) show touch therapy-dependent changes in salivary oxytocin concentrations.

7.
Article in English | MEDLINE | ID: mdl-26737529

ABSTRACT

An ultra wideband (UWB) technology is a potential candidate for implant body area networks (BANs), where wireless communications are established between inside and outside of a human body. The UWB can accomplish higher data rate than the other frequency band for the implant communication. However, due to its high frequencies, the UWB signals suffer from quite large attenuation in the implant communication link, which makes it difficult to achieve reliable communications. For achieving reliable communication, it is well known that a spatial diversity technique is efficient without any frequency extension. In our previous works, we developed a transmit polarization diversity antenna for the UWB implant communication. However, optimal UWB modulation scheme for transmit diversity were rarely discussed. In this paper, in order to investigate the optimal UWB modulation schemes for implant communication with transmit diversity, we compare the communication performances of UWB-impulse radio (UWB-IR) and multiband-orthogonal frequency division multiplexing (MB-OFDM). For this purpose, we first analyze the propagation characteristics in the implant UWB channel, which ranges from 3.4 GHz to 4.8 GHz, using a finite difference time domain (FDTD) numerical analysis technique. Then, we evaluate and discuss the communication performances of both modulation schemes for the transmit polarization diversity from the viewpoint of the BER and the required transmit power.


Subject(s)
Computer Communication Networks/instrumentation , Prostheses and Implants , Wireless Technology/instrumentation , Humans
8.
Article in English | MEDLINE | ID: mdl-25571602

ABSTRACT

In order to design an optimized transceiver structure of ultra wideband (UWB) transmission in in-body to out-of-body communications, it is necessary to make the transceiver structure be easily adjustable in order to realize a good communication performance in an experimental environment. For this purpose, we first implement our develop UWB-impulse radio (IR) receiver structure for the in-body to out-of-body communication in a field programmable gate array (FPGA) board, and evaluate the fundamental communication performance of the FPGA-implemented UWB-IR receiver by a biological-equivalent liquid phantom experiment. The FPGA configuration results indicate that our FPGA realization of the UWB-IR receiver has accomplished good communication performance with few FPGA slices. Moreover, the evaluation results in the liquid phantom experiment show that the FPGA-implemented UWB-IR receiver can achieve a bit error rate (BER) of 10(-3) up to a communication distance of 70 mm with ensuring a high data rate of 2 Mbps.


Subject(s)
Computer Communication Networks/instrumentation , Monitoring, Ambulatory/instrumentation , Transducers , Equipment Design , Humans , Models, Statistical , Monitoring, Ambulatory/methods , Phantoms, Imaging , Reproducibility of Results , Signal Processing, Computer-Assisted , Software , Wireless Technology
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