505 research outputs found
Robust Symbol-Level Precoding for Massive MIMO Communication Under Channel Aging
This paper investigates the robust design of symbol-level precoding (SLP) for
multiuser multiple-input multiple-output (MIMO) downlink transmission with
imperfect channel state information (CSI) caused by channel aging. By utilizing
the a posteriori channel model based on the widely adopted jointly correlated
channel model, the imperfect CSI is modeled as the statistical CSI
incorporating the channel mean and channel variance information with spatial
correlation. With the signal model in the presence of channel aging, we
formulate the signal-to-noise-plus-interference ratio (SINR) balancing and
minimum mean square error (MMSE) problems for robust SLP design. The former
targets to maximize the minimum SINR across users, while the latter minimizes
the mean square error between the received signal and the target constellation
point. When it comes to massive MIMO scenarios, the increment in the number of
antennas poses a computational complexity challenge, limiting the deployment of
SLP schemes. To address such a challenge, we simplify the objective function of
the SINR balancing problem and further derive a closed-form SLP scheme.
Besides, by approximating the matrix involved in the computation, we modify the
proposed algorithm and develop an MMSE-based SLP scheme with lower computation
complexity. Simulation results confirm the superiority of the proposed schemes
over the state-of-the-art SLP schemes
MicroRNA-140-5p inhibits cellular proliferation, migration and invasion by downregulating AKT/STAT3/NF-κB pathway in breast carcinoma cells
MicroRNA-140-5p (miR-140-5p) plays a pivotal role in human cancers. However, its role and molecular mechanisms in breast carcinoma are not fully explored. Using miR-140-5p transfected breast cancer cell line MDA-MB-231, several in vitro experiments were performed and described in this paper. They consist of the cell proliferation assay, wound healing assay, transwell assay, colony formation assays and qRTPCR. Expression levels of target proteins were determined using western blotting. In addition, experiments on animal models were performed to study the possible role of miR-140-5p in tumorigenesis of breast carcinoma cells. The induction of experimental breast tumor in mice model was achieved through the incorporation of MDA-MB-231 tumor cells subcutaneously into the middle left side of the mice. The results showed that miR-140-5p up-regulation significantly suppresses proliferation, cellular invasion and migration of breast carcinoma cells. Furthermore, miR-140-5p up-regulation stops breast cancer cells at G0/G1 phase. The results of the animal model indicated that up-regulation of miR-140-5p suppresses its tumorigenic ability. Moreover, we also found that miR-140-5p up-regulation reduces the phosphorylation level of STAT3, p65, and AKT. In addition, miR-140-5p overexpression significantly decreases CDK2 expression while increasing E-cadherin expression level. These data revealed that miR-140-5p suppressed tumor progression of breast carcinoma cells through inhibition of the AKT/STAT3/NF-κB pathway. Taken the present study results together, we can conclude that miR-140-5p may act as a novel target in microRNA-targeting anticancer strategy for the treatment of breast cancer
Multiform Evolution for High-Dimensional Problems with Low Effective Dimensionality
In this paper, we scale evolutionary algorithms to high-dimensional
optimization problems that deceptively possess a low effective dimensionality
(certain dimensions do not significantly affect the objective function). To
this end, an instantiation of the multiform optimization paradigm is presented,
where multiple low-dimensional counterparts of a target high-dimensional task
are generated via random embeddings. Since the exact relationship between the
auxiliary (low-dimensional) tasks and the target is a priori unknown, a
multiform evolutionary algorithm is developed for unifying all formulations
into a single multi-task setting. The resultant joint optimization enables the
target task to efficiently reuse solutions evolved across various
low-dimensional searches via cross-form genetic transfers, hence speeding up
overall convergence characteristics. To validate the overall efficacy of our
proposed algorithmic framework, comprehensive experimental studies are carried
out on well-known continuous benchmark functions as well as a set of practical
problems in the hyper-parameter tuning of machine learning models and deep
learning models in classification tasks and Predator-Prey games, respectively.Comment: 12 pages,6 figure
Overview on the Role of Advance Genomics in Conservation Biology of Endangered Species
In the recent era, due to tremendous advancement in industrialization, pollution and other anthropogenic activities have created a serious scenario for biota survival. It has been reported that present biota is entering a "sixth" mass extinction, because of chronic exposure to anthropogenic activities. Various ex situ and in situ measures have been adopted for conservation of threatened and endangered plants and animal species; however, these have been limited due to various discrepancies associated with them. Current advancement in molecular technologies, especially, genomics, is playing a very crucial role in biodiversity conservation. Advance genomics helps in identifying the segments of genome responsible for adaptation. It can also improve our understanding about microevolution through a better understanding of selection, mutation, assertive matting, and recombination. Advance genomics helps in identifying genes that are essential for fitness and ultimately for developing modern and fast monitoring tools for endangered biodiversity. This review article focuses on the applications of advanced genomics mainly demographic, adaptive genetic variations, inbreeding, hybridization and introgression, and disease susceptibilities, in the conservation of threatened biota. In short, it provides the fundamentals for novice readers and advancement in genomics for the experts working for the conservation of endangered plant and animal species.</p
Aquatic Plant Genomics: Advances, Applications, and Prospects
Genomics is a discipline in genetics that studies the genome composition of organisms and the precise structure of genes and their expression and regulation. Genomics research has resolved many problems where other biological methods have failed. Here, we summarize advances in aquatic plant genomics with a focus on molecular markers, the genes related to photosynthesis and stress tolerance, comparative study of genomes and genome/transcriptome sequencing technology
Catechins-Modified Selenium-Doped Hydroxyapatite Nanomaterials for Improved Osteosarcoma Therapy Through Generation of Reactive Oxygen Species
Osteosarcoma is the most common bone cancer with limited therapeutic options. It can be treated by selenium-doped hydroxyapatite owing to its known antitumor potential. However, a high concentration of Se is toxic toward normal and stem cells whereas its low concentration cannot effectively remove cancer cells. Therefore, the current study was aimed to improve the anticancer activity of Se-HAp nanoparticles through catechins (CC) modification owing to their high cancer therapeutic value. The sequentially developed catechins modified Se-HAp nanocomposites (CC/Se-HAp) were characterized for various physico-chemical properties and antitumor activity. Structural analysis showed the synthesis of small rod-like single phase HAp nanoparticles (60 +/- 15 nm), which effectively interacted with Se and catechins and formed agglomerated structures. TEM analysis showed the internalization and degradation of CC/Se-HAp nanomaterials within MNNG/HOS cells through a non-specific endocytosis process. Cell toxicity analysis showed that catechins modification improved the antitumor activity of Se-HAp nanocomposites by inducing apoptosis of human osteosarcoma MNNG/HOS cell lines, through generation of reactive oxygen species (ROS) which in turn activated the caspase-3 pathway, without significantly affecting the growth of human normal bone marrow stem cells (hBMSCs). qPCR and western blot analyses revealed that casp3, p53, and bax genes were significantly upregulated while cox-2 and PTK-2 were slightly downregulated as compared to control in CC/Se-HAp-treated MNNG/HOS cell lines. The current study of combining natural biomaterial (i.e., catechins) with Se and HAp, can prove to be an effective therapeutic approach for bone cancer therapy.</p
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