A 64-channel massive multiple-input multiple-output (MIMO) transceiver with a fully digital beamforming (DBF) architecture for fifth-generation millimeter-wave communications is presented in this ...paper. The DBF-based massive MIMO transceiver is operated at 28-GHz band with a 500-MHz signal bandwidth and the time division duplex mode. The antenna elements are arranged as a 2-D array, which has 16 columns (horizontal direction) and 4 rows (vertical direction) for a better beamforming resolution in the horizontal plane. To achieve half-wavelength element spacing in the horizontal direction, a new sectorial transceiver array design with a bent substrate-integrated waveguide is proposed. The measured results show that an excellent RF performance is achieved. The system performance is tested with the over-the-air technique to verify the feasibility of the proposed DBF-based massive MIMO transceiver for high data rate millimeter-wave communications. Using the beam-tracking technique and two streams of QAM-64 signals, the proposed millimeter-wave MIMO transceiver can achieve a steady 5.3-Gb/s throughput for a single user in fast mobile environments. In the multiple-user MIMO scenario, by delivering 20 noncoherent data streams to eight four-channel user terminals, it achieves a downlink peak data rate of 50.73 Gb/s with the spectral efficiency of 101.5 b/s/Hz.
A low-complexity metallic tapered slot antenna (TSA) array for millimeter-wave multibeam massive multiple-input multiple-output communication is proposed in this paper. Good beamforming performance ...can be achieved by the developed antenna array because the element spacing can easily meet the requirement of half-wavelength in the H-plane. The antenna element is fed by a substrate-integrated waveguide, which can be directly integrated with the millimeter-wave circuits. The proposed TSA is fabricated and measured. Measured results show that the reflection coefficient is lower than -15 dB Voltage Standing Wave Ratio ((VSWR) ≤ 1.45) within the frequency range from 22.5 to 32 GHz, which covers the 24.25-27.5-GHz band proposed by International Telecommunications Union (ITU) and the 27.5-28.35-GHz band proposed by Federal Communications Commission (FCC) for 5G. The gain of the antenna element varies from 8.2 to 9.6 dBi over the frequency range of 24-32 GHz. The simulated and measured results also illustrate good radiation patterns across the wide frequency band (24-32 GHz). A 1 × 4 H-plane array integrated with the multichannel millimeter-wave transceivers on one PCB is demonstrated and excellent performance is achieved.
A high-gain dual-band resonant cavity antenna (RCA) for the fifth-generation (5G) millimeter-wave (MMW) communications is presented in this letter. The proposed antenna provides the high gain and ...large gain-bandwidth product over the 28 GHz band and the 38 GHz band. The heights of the second- and third-order resonant in the RCA are optimized for dual-band operation. Improvements on the gain and the bandwidth are achieved in both bands when stepped rings are added. The gain is further increased with a circular patch on a partially reflective surface, which is made by a substrate of high permittivity. Finally, a prototype is designed, simulated, and verified through measurement. Good performance is achieved: in the 26.5-28 GHz band, the bandwidth is 5.5% and the peak gain is 20.3 dBi; in the 37.5-39.4 GHz band, the bandwidth is 4.9% and the peak gain is 20.4 dBi. The proposed antenna has the features of low cost and easy fabrication as well.
External stimuli-responsive nanomedicine with desirable repetitive on-demand drug release character is postulated to greatly accommodate patients' flexible medication regime. To this object, ...light-activatable liposomes (Pt/Ce6-LP) integrated with both a Ce6 photodynamic component and a tetravalent platinum prodrug (Pt(IV)) chemotherapeutic component are engineered. This multifunctional system was rationally designed using unsaturated phospholipid to achieve repetitive on-demand drug release under discontinuous light irradiation, thus performing chemo-photodynamic therapy effect and immunopotentiation in hypoxic tumor. Furthermore, glutathione (GSH) consumption during transformation from Pt(IV) prodrug to Pt(II) can avoid depletion of reactive oxygen species (ROS) in photodynamic therapy (PDT). Note this positive feedback loop appears to remodel the redox balance of H2O2 and GSH in tumors, alleviating the hypoxic tumor microenvironment. The alleviated hypoxia is found to be critical to the enhancement of PDT efficacy, reversal of cisplatin resistance in tumors, and polarization of tumor-associated macrophages (TAMs) to the immunocompetent M1-phynotype. Pt/Ce6-LP with light radiation demonstrates significant antitumor effect and persistent post-medication inhibition in patient-derived tumor xenograft model of hepatocellular carcinoma.
A light-activatable liposome (Pt/Ce6-LP) was constructed to realize repetitive on-demand drug release and intensified PDT/chemotherapy on patient-derived tumor xenograft model of hepatocellular carcinoma. Pt/Ce6-LP with light irradiation overcame hypoxia-relative therapeutic resistance via a positive feedback loop and increased M1-TAMs populations to potentiate immune activity for hypoxic tumor treatment. Display omitted
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
While the composition and diversity of soil microbial communities play a central and essential role in biogeochemical cycling of nutrients, they are known to be shaped by the physical and chemical ...properties of soils and various environmental factors. This study investigated the composition and diversity of microbial communities in 48 samples of seasonally frozen soils collected from 16 sites in an alpine wetland region (Lhasa River basin) and an alpine forest region (Nyang River basin) on the Tibetan Plateau using high-throughput sequencing that targeted the V3-V4 region of 16S rRNA gene. The dominant soil microbial phyla included Proteobacteria, Acidobacteria, and Actinobacteria in the alpine wetland and alpine forest ecosystems, and no significant difference was observed for their microbial composition. Linear discriminant analysis Effect Size (LEfSe) analysis showed that significant enrichment of Hymenobacteraceae and Cytophagales (belonging to Bacteroidetes) existed in the alpine wetland soils, while the alpine forest soils were enriched with Alphaproteobacteria (belonging to Proteobacteria), suggesting that these species could be potential biomarkers for alpine wetland and alpine forest ecosystems. Results of redundancy analysis (RDA) suggest that the microbial community diversity and abundance in the seasonally frozen soils on the Tibetan Plateau were mainly related to the total potassium in the alpine wetland ecosystem, and available potassium and soil moisture in the alpine forest ecosystem, respectively. In addition, function prediction analysis by Tax4Fun revealed the existence of potential functional pathways involved in human diseases in all soil samples. These results provide insights on the structure and function of soil microbial communities in the alpine wetland and alpine forest ecosystems on the Tibetan Plateau, while the potential risk to human health from the pathogenic microbes in the seasonally frozen soils deserves attention.
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•Bacterial α-diversity decreased with altitude in the Tibetan alpine wetland soils.•Bacterial β-diversity was significantly different in alpine wetland and forest soils.•Wetland and forest ecosystems showed little difference in soil microbial composition.•Total/available K and moisture influenced the structure of soil microbial communities.•Potential functional pathways involved in human disease were identified in the soils.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
A simple technique is developed in this communication to increase the axial ratio (AR) bandwidth and achieve good impedance matching of a single-fed low profile circularly polarized (CP) stacked ...patch antenna. The proposed antenna is composed of a driven patch layer and a parasitic patch layer. The driven patch layer consists of a truncated main patch, a parasitic patch and a probe feeding structure while the stacked patch layer is comprised of five patches. The proposed antenna combines the attractive features such as low profile, wide impedance and AR bandwidths, high gain as well as easiness of design, manufacture and integration. The antenna operating at 6 GHz band is designed and fabricated on an FR4 substrate and the overall volume is 0.8 λ 0 ×0.8 λ 0 ×0.09 λ 0 . Measured results show that the antenna achieves an impedance bandwidth of more than 30% for dB, a 3-dB AR bandwidth of about 20.7%, and a gain level of over 7.9 dBi within the 3-dB AR bandwidth.
•Higher BPA exposure may influence the early outcomes of IVF-ET.•BPA could induce autophagy and endocrine dysfunction in GCs.•AMPK/mTOR/ULK1 pathway might be the key player in BPA-induced autophagy ...in GCs.
Bisphenol A (BPA) is a widespread endocrine-disrupting chemical with estrogen like effects, which could interfere with the human reproductive system by disrupting the normal function of granulosa cells (GCs) leading to abnormal ovarian function. However, the mechanism of its toxicity on human GCs has not been clearly described thus far.
106 normogonadotropic infertile women undergoing their first in-vitro fertilization-embryo transfer (IVF-ET) cycle were recruited. Urinary BPA level and the early outcomes of IVF-ET were analysed. Patients were divided to low and high BPA exposure groups using the median urinary BPA concentration as the cut-off value. In-vivo and in-vitro studies were conducted using mice and human granulosa cell line (KGN cells). Female Kunming mice approximately 6–8 weeks of age were poisoned with BPA at different dosages (1, 10 or 100 μg/kg) by oral gavage once daily for 2 weeks, while KGN cells were exposed to BPA at the concentration of 1, 10 or 100 nM for 24 h, 48 h or 72 h. BPA-induced ovarian morphologic changes were analysed by histopathology investigation. Cell viability and apoptosis were evaluated using CCK-8, TUNEL and flowcytometric, respectively. Hormone levels were determined using ELISA and the molecular mechanism studies were conducted using immunofluorescence, RT-PCR and western blots.
The oocyte retrieval rate, maturation rate and embryo implantation rate significantly decreased with the higher level of urinary BPA concentration. Peak E2 level was lower in high BPA group, but no statistical significance could be observed. In BPA treated mice, cystic dilation of the follicles with a decreased number of GCs could be observed histopathologically. Decreased E2, P4 and AMH level and GCs autophagy could be detected both in-vivo and in-vitro with the activation of AMPK/mTOR/ULK1 signalling pathway. As being confirmed in KGN cells, phosphorylated AMPK and ULK1 increased while phosphorylated mTOR decreased, and by inhibition autophagy using knockdown of AMPK or 3-MA, adverse effects of BPA exposure in-vitro could be reversed.
BPA exposure might abnormally influence human ovarian functions leading to abnormal folliculogenesis by activation of autophagy in GCs through AMPK/mTOR/ULK1 pathway.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Heteroatom-doped carbon dots (CDs), due to their excellent photoluminescence (PL) properties, attracted widespread attention recently and demonstrated immense promise for diverse applications, ...particularly for biological applications. The objective of this feature article is to provide a comprehensive overview of the recent progress in the research and development of heteroatom-doped CDs and a detailed description of the influence of single or co-doping heteroatoms on their PL behavior. The most recent understanding and critical insights into the PL mechanism of heteroatom-doped CDs are also highlighted. Moreover, potential bio-related applications of heteroatom-doped CDs in biosensing, bioimaging, and theranostics are also reviewed. This state-of-the-art review will provide a platform for understanding the intricate details of heteroatom-doped CDs, a summary of the latest progress in the field, and related applications in biology and is expected to inspire further developments in this exciting class of materials.
This review summarized the recent progress in the synthesis, characterization, properties, photoluminescence mechanism and biological applications of carbon dots.
Cancer remains one of the world's leading causes of death. However, most conventional chemotherapeutic drugs only show a narrow therapeutic window in patients because of their inability to ...discriminate cancer cells from healthy cells. Nanoparticle‐based therapeutics (termed nanotherapeutics) have emerged as potential solutions to mitigate many obstacles posed by these free drugs. Deep insights into knowledge of the tumor microenvironment and materials science make it possible to construct nanotherapeutics that are able to release cargoes in response to a variety of internal stimuli and external triggers. Therefore, such highly sophisticated nanosystems could help impede the premature release of toxic drugs in the blood circulation or healthy tissues, thus enhancing the safety profiles of encapsulated drugs. In this context, this review offers a comprehensive overview of several specific stimuli, including internal stimuli (e.g., pH, temperature, enzyme, redox, and H2O2) and external stimuli (e.g., magnetic, photo, and ultrasound). We envision that applications of these smart nanotherapeutics can benefit cancer patients and provide a good chance for clinical translation of many nanoparticle formulas.
This article is categorized under:
Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease
Diagnostic Tools > Diagnostic Nanodevices
Diagnostic Tools > in vitro Nanoparticle‐Based Sensing
Nanotherapeutics have emerged as potential solutions to fulfill the promise of Paul Ehrlich's magic bullet concept. This review offers a comprehensive overview of the construction of nanotherapeutics that are able to precisely release drug cargoes in response to a variety of internal stimuli and external triggers. The applications of these smart systems can benefit cancer patients and provide a good chance for clinical translation of many nanoparticle formulas.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
To address the requirements of biomedical applications including biosensing, bioimaging, and drug delivery, fluorescent nanomaterials served as efficient tools in many cases. Among them, ...near‐infrared quantum dots (NIR QDs) have been used as novel fluorescent labels for their binary advantages of both QDs and NIR light. In this review, through collecting references in recent 10 years, we have introduced basic structures and properties of NIR QDs and summarized the classification and the related synthetic methods. This review also highlights the functionalization and surface bioconjugation of NIR QDs, and their biomedical applications in biosensing, bioimaging, and drug delivery.
This article is categorized under:
Diagnostic Tools > Diagnostic Nanodevices
Diagnostic Tools > In Vitro Nanoparticle‐Based Sensing
Diagnostic Tools > In Vivo Nanodiagnostics and Imaging
Extinction coefficient value of water and oxy‐ and deoxyhemoglobin plotted ranging from visible to near‐infrared wavelength.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
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