This study proposes an improved method for sector nulling in the radiation pattern of rectangular phased array antennas using two different synthesis techniques; an orthogonal Discrete Fourier ...transform and a quasi‐orthogonal Dolph‐Tschebyscheff based technique. In traditional synthesis techniques, broad elemental beams serve as local field basis functions (FBFs) in an array. Instead, the proposed methods produce low sidelobe narrow beams as FBFs. A set of these FBFs can effectively constitute the array's radiation pattern in a confined angular region. By properly weighting these FBFs, sector pattern nulls in a designated angular range are synthesized without severely distorting the patterns outside this area. The FBFs' optimal weights can be efficiently calculated using a nonlinear minimum least squares error technique, which is later transformed into the array's elemental excitation coefficients. Along with faster convergence, this technique allows control over peak sidelobe level, null depth, and width, making it suitable for GPS anti‐jamming, 5G communications, and other applications requiring interference suppression.
Key Points
Two localized beam cancellation methods for antenna pattern nulling are proposed
The theoretical formulations of a Discrete Fourier Transform and a Dolph‐Tschebyscheff based algorithm are explained
Numerical examples demonstrating the effectiveness of the algorithms are presented
Hospice care focuses on improving the quality of end-of-life care and respecting patients’ preferences regarding end-of-life treatment. The impact of coronavirus disease 2019 (COVID-19) on the ...utilization of hospice services is unknown.
To investigate the utilization of hospice care services before and during the COVID-19 pandemic.
All patients (n = 19,900) cared for at Taipei City Hospital from January 2019 to April 2020 were divided into three time points: January–April 2019 (before COVID-19), May–December 2019 (interim), and January–April 2020 (during COVID-19). This cohort study compared the monthly utilization of hospice services before and during the COVID-19 pandemic.
There was no significant difference in hospice home visits (194 vs. 184; P = 0.686) and new enrollments (15 vs. 14; P = 0.743) to hospice home care before and during the pandemic. However, the bed occupancy rate in hospice units in the hospital was significantly reduced from 66.2% before the pandemic to 37.4% during the pandemic (P = 0.029), whereas that in nonhospice units had a nonsignificant decrease from 81.6% before the pandemic to 71.8% during the pandemic (P = 0.086). During the pandemic, the number of inpatient days was affected more severely in hospice units than in nonhospice units (−42.4% vs. −10.9%; P = 0.029).
This study suggests that hospice home care services were maintained during the COVID-19 pandemic, while the utilization of hospice inpatient care services reduced. Home care for hospice patients is an essential component of palliative care during a pandemic.
In this paper, we present the application of the Rotman lens beamformer (RLB) to excite a large-phased array of antennas for multibeam radiation with confined sidelobe levels (SLLs) and coverage ...area. For a compact architecture, the array is divided into subarrays of interleaved elements, where each subarray is excited by a stacked RLB with a much smaller physical size. The basic concept is to realize the theoretical phases required to produce a set of orthogonal beams by the discrete Fourier transform representation of excitation weightings. Thus, the focal points to feed the Rotman lens are selected on an elliptic arc to produce directional beams among this set of orthogonal beams. A periodic phase impression is afterward performed to excite the residue elements excluding the subarrays, which subsequently creates an amplitude taper of excitation to reduce SLLs. Theoretical concepts and numerical examples examining the effects of phase distortion arising from the RLB design in the beamforming are first investigated to validate the feasibility and applicable scope. Experimental measurement over an antenna prototype is presented to validate the design.
Background: Magnolol, a major bioactive component extracted from Magnolia officinalis, exerts several beneficial effects, such as anti-inflammatory and anti-hypertensive activities.
Purpose: In this ...study, we investigated whether magnolol has a protective effect on pneumonectomy and monocrotaline-induced pulmonary arterial hypertension (PAH) in rats.
Design/Methods: The alterations of right ventricular (RV) hypertrophy, pulmonary vascular remodeling, histopathological parameters, and related gene expression and signaling pathways in lungs by magnolol treatment were studied in the PAH rats.
Results: Administration of magnolol greatly ameliorated the characteristic features of PAH, including increased pulmonary arterial pressure, RV hypertrophy, and pulmonary vascular remodeling. Moreover, magnolol inhibited angiotensin-converting enzyme (ACE)/angiotensin II (Ang II)/Ang II type 1 receptor (AT-1R) cascade, whereas upregulates ACE2 in the lungs of PAH rats. The overexpression of endothelin-1 (ET-1) and ETA receptor occurred in the PAH rats was significantly attenuated by magnolol through inhibition of Akt/ERK1/2/GSK3β/β-catenin pathway. Compared with that of untreated PAH rats, higher expression of endothelial nitric oxide synthase, and lower expression of inducible nitric oxide synthase and O2− production in lungs were observed in magnolol-treated PAH rats.
Conclusion: We demonstrated that treatment with magnolol reduces the development of PAH induced by pneumonectomy and monocrotaline in rats, and suppressing Ang II and ET-1-mediated processes may contribute to its protective effects. These findings suggest that magnolol may be a potential agent for PAH therapy.
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To investigate the association between serum albumin levels and cause-specific mortality among community-dwelling older adults. This cohort study was based on data obtained from the ...government-sponsored Annual Geriatric Health Examination Program for the older adults in Taipei City between 2006 and 2010. The study sample consisted of 77,531 community-dwelling Taipei citizens (≥65 years old). Mortality was determined by matching the participants' medical records with national death files. Serum albumin levels were categorized into <3.6, 3.6–3.7, 3.8–3.9, 4.0–4.1, 4.2–4.3, and ≥4.4 g/dL. Cox proportional hazards regression models were used to evaluate the association between albumin levels and cause-specific mortality. Spline regression was used to calculate the risk of mortality associated with albumin levels, modeled as continuous variables. Community-dwelling older adults had a mean albumin level of 4.3 g/dL, which significantly reduced by age. Compared to albumin levels ≥4.4 g/dL, mildly low albumin levels (4.2–4.3 g/dL) were associated with an increased mortality risk (hazard ratio HR: 1.16, 95% confidence interval CI: 1.05–1.28 for all-cause mortality), and albumin levels <4.2 g/dL were associated with significantly higher rates of all-cause, cancer, cardiovascular, and respiratory mortalities. In the spline regression, the curve of mortality risk was relatively flat at an albumin level ≥4.4 g/dL, and the mortality risk gradually increased as the albumin level declined. Albumin levels ≥4.4 g/dL were associated with better survival among community-dwelling older adults, and mortality risk increased as the albumin level decreased.
•Albumin ≥4.4 g/dL had better survival in community-dwelling older adults.•Mortality risks increased gradually as the albumin level decreased.•Even mildly low albumin levels (4.2–4.3 g/dL) increased mortality.
This study investigated the prognostic effects of genomic biomarkers for predicting chemoradiotherapy (CRT)-based treatment outcomes in patients with adenocarcinoma (AC) of the uterine cervix. In ...all, 21 patients receiving definitive CRT were included. In accordance with the International Federation of Gynecology and Obstetrics (FIGO) staging system, 5, 8, and 8 patients were classified as having stage IB3, II, and III disease, respectively. Pretreatment biomarkers were analyzed using tissue microarrays from biopsy specimens. Genomic alterations were examined by next-generation sequencing (NGS). The outcome endpoints were disease-free survival (DFS), distant metastasis-free survival (DMFS), and local relapse-free survival (LRFS). A Cox regression model was used to examine the prognostic effects of the biomarkers and clinical parameters. The presence of myeloid cell leukemia-1 (
) gene amplification and a lower immunohistochemical (IHC) marker of tumor necrotic factor alpha (TNF-α) H-score were two prognostic factors for inferior DFS. The four-year DFS was 28% and 68% for patients with or without MCL1 copy number gain, respectively (
= 0.028). In addition, MCL1 amplification predicted poor DMFS. A lower tumor mutation number (TMN) calculated from nonsynonymous mutations was associated with lower LRFS. For patients with adenocarcinoma of the uterine cervix receiving definitive CRT, prognostic information can be supplemented by
amplification, the TMN, and the TNF-α H score.
This paper presents an effective excitation synthesis algorithm of phased arrays of antennas to optimize the radiation patterns under minimum mutual coupling/induction interferences between two ...nearby arrays. The optimization goal is to minimize the inter-array interferences in an attempt to retain their radiation beam characteristics. Furthermore, a cost function is defined to reduce the inter-array reaction and the excitation weighting deviations from the desired ones for directional beam radiations by embedding a coupling reduction factor (CRF). The resulting solutions are in a simple closed-form for easy implementation. Besides, the mutual coupling/induction mechanisms are effectively interpreted using the singular-value decomposition (SVD) method to create an eigenspace for signal representations and the complementary null space. Finally, theoretical and numerical full-wave simulation examples are presented to validate the proposed mutual coupling/induction suppression method.
ABSTRACT
This study aimed to isolate, culture, and characterize duck primordial germ cells (PGCs) and to compare these cells with chicken PGCs. We first cultured Muscovy duck (Cairina moschata) ...circulating PGCs and gonadal PGCs (gPGCs) in the modified serum-containing medium used to amplify chicken PGCs. gPGCs were found to proliferate better in serum-free chemically defined medium than in serum-containing medium. Thereafter, gPGCs were similarly isolated from 2 other duck breeds, the Pekin duck (Anas platyrhynchos) and the hybrid mule duck (C. moschata × A. platyrhynchos), and amplified for a limited period of time in the chemically defined culture condition, but sufficiently to be characterized and transplanted. Cultured gPGCs of all 3 duck breeds were characterized by Periodic acid-Schiff staining, immunocytochemical staining, and expression analysis of germline-specific and pluripotency genes. Cultured duck gPGCs colonized the gonads after being genetically labeled and injected into recipient embryos. Taken together, these results demonstrate that duck PGCs retain their germline characteristics after being isolated, expanded in vitro, and genetically modified. Further studies are required to establish the optimal conditions for long-term culture of duck PGCs, which may involve supplementing the culture medium with other growth factors or compounds.
Patients with advanced-stage non-small-cell lung cancer (NSCLC) are susceptible to malnutrition and develop folate deficiency (FD). We previously found that folate deprivation induces drug resistance ...in hepatocellular carcinoma; here, we assessed whether disrupted cytoplasmic folate metabolism could mimic FD-induced metastasis and affect the sensitivity of NSCLC cells to epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs). We examined whether cytosolic folate metabolism in NSCLC cells was disrupted by FD or the folate metabolism blocker pemetrexed for 1–4 weeks. Our results revealed an increase in NF-κB overexpression–mediated epithelial-mesenchymal transition biomarkers: N-cadherin, vimentin, matrix metalloproteinases (MMPs), SOX9, and SLUG. This finding suggests that the disruption of folate metabolism can drastically enhance the metastatic properties of NSCLC cells. Cytosolic FD also affected EGFR-TKI cytotoxicity toward NSCLC cells. Because SLUG and N-cadherin are resistance effectors against gefitinib, the effects of SLUG knockdown in folate antagonist–treated CL1-0 cells were evaluated. SLUG knockdown prevented SLUG/NF-κB/SOX9-mediated invasiveness and erlotinib resistance acquisition and significantly reduced pemetrexed-induced gelatinase activity and MMP gene expression. To summarize, our data reveal two unprecedented adverse effects of folate metabolism disruption in NSCLC cells. Thus, the folic acid status of patients with NSCLC under treatment can considerably influence their prognosis.
Patients with primary aldosteronism are associated with increased myocardial fibrosis. Galectin-3 is one of the most important mediators between macrophage activation and myocardial fibrosis.
To ...investigate whether aldosterone induces galectin-3 secretion in vitro and in vivo.
We investigated the possible molecular mechanism of aldosterone-induced galectin-3 secretion in macrophage cell lines (THP-1 and RAW 264.7 cells). Aldosterone induced galectin-3 secretion through mineralocorticoid receptors via the PI3K/Akt and NF-κB transcription signaling pathways. In addition, aldosterone-induced galectin-3 expression enhanced fibrosis-related factor expression in fibroblasts. We observed that galectin-3 mRNA from peripheral blood mononuclear cells and serum galectin-3 levels were both significantly increased in mice implanted with aldosterone pellets on days 7 and 14. We then conducted a prospective preliminary clinical study to investigate the association between aldosterone and galectin-3. Patients with aldosterone-producing adenoma had a significantly higher plasma galectin-3 level than patients with essential hypertension. One year after adrenalectomy, the plasma galectin-3 level had decreased significantly in the patients with aldosterone-producing adenoma.
This study demonstrated that aldosterone could induce galectin-3 secretion in vitro and in vivo.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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