Near-Field Beam Training in Terahertz Communications with Hybrid Beamforming Architecture.

Terahertz (THz) communication has a large available bandwidth, which is expected to be deployed in future communication networks. As THz wave suffers from severe propagation loss in wireless transmission, we consider a THz near-field scenario where a base station (BS) is equipped with a large-scale antenna array with a low-cost hybrid beamforming architecture to serve mobile users nearby. However, the large-scale array and the user mobility incur difficulty in channel estimation. To tackle this issue, we propose a near-field beam training scheme that can align a beam to the user in a fast way by searching the codebook. Specifically, the BS employs a uniform circular array (UCA), and the radiation pattern of the beams in our proposed codebook appears as ellipsoids. To cover the serving zone with the minimum codebook size, we develop a near-field codebook by tangent arrangement approach (TAA). To reduce the time overhead, we leverage the hybrid beamforming architecture to realize multi-beam training concurrently since each RF chain can enable a codeword whose element has a constant magnitude. Numerical results validate that our proposed UCA near-field codebook achieves less time cost while achieving a comparable coverage performance compared to the conventional near-field codebook.

miR-128-3p regulates chicken granulosa cell function via 14-3-3ß/FoxO and PPAR-γ/LPL signaling pathways.

MicroRNAs (miRNAs) are class of 22 nt short RNA sequences which inhibit protein translation through binding to the 3'UTR of its target genes. The continuous ovulatory property of chicken follicle makes it a perfect model for studying granulosa cell (GC) functions. In this study, we found that large number of miRNAs including miR-128-3p, were differentially expressed in the GCs of F1 and F5 follicles of chicken. Subsequently, the results revealed that miR-128-3p inhibited proliferation, the formation of lipid droplets, and hormone secretion in chicken primary GCs through directly targeting YWHAB and PPAR-γ genes. To determine the effects of 14-3-3ß (encoded by YWHAB) protein on GCs functions, we overexpressed or inhibited the expression of YWHAB, and the results showed that YWHAB inhibited the function of FoxO proteins. Collectively, we found that miR-128-3p was highly expressed in the chicken F1 follicles compared to the F5 follicles. In addition, the results indicated that miR-128-3p promoted GC apoptosis through 14-3-3ß/FoxO pathway via repressing YWHAB, and inhibited lipid synthesis by impeding the PPAR-γ/LPL pathway, as well as reduced the secretion of progesterone and estrogen. Taken together, the results showed that miR-128-3p plays a regulatory role in chicken granulosa cell function via 14-3-3ß/FoxO and PPAR-γ/LPL signaling pathways.

The dynamic changes of HBV quasispecies diversity in infancy after immunoprophylaxis failure: a prospective cohort study.

BACKGROUND: Previous works have observed that younger infants with chronic hepatitis B virus (HBV) infection are more responsive to antiviral treatment. However, the underlying mechanism remains unclear. In this study, the dynamic changes of HBV quasispecies in infants with immunoprophylaxis failure were investigated to provide virological explanations for clinical management on infantile antiviral therapy. METHODS: Thirteen 7-month-old infants with immunoprophylaxis failure and their mothers were enrolled from a prospective cohort, and 8 of them were followed up to 3 years old. The sequences of HBV quasispecies were analyzed by the full-length genome clone-based sequencing, and compared among mothers and their infants at different ages. RESULTS: The results revealed that the complexity, mutation frequency and genetic distance of HBV quasispecies decreased significantly at full-length, partial open reading frames and regulatory regions of HBV genome at nucleotide level in 7-month-old infants comparing with their mothers, whereas increased significantly to near the maternal level when infants grew up to 3 years old. Furthermore, similar changes were also found in Core, PreS2, RT and P regions of HBV genome at amino acid level, especially for potential NAs-resistant mutants in RT region and immune-escape mutants in Core and PreS2 regions. CONCLUSIONS: This study uncovered the evolution of HBV quasispecies in infancy after mother-to-child transmission, which may provide the virological evidence for explaning that younger children are more responsive to antiviral therapy.

Improving the short-term frequency stability of a magnetic-state-selected cesium beam clock with optical detection.

The microwave spectrum line shape and the signal-to-noise ratio of a compact optically detected magnetic-state-selection cesium beam clock are analyzed in this paper. As the noise analysis shows, the performance is related to the atomic utilization ratio and locking parameters when the laser frequency noise is the dominant noise source. Methods are adopted for realizing better short-term frequency stability of the clock, including using a highly efficient state-selection cesium beam tube, optimizing the locking parameters, and stabilizing the microwave power to maximize the error signal. After optimization, the signal-to-noise ratio of the clock reaches 7.0 × 103 in a bandwidth of 1 Hz and the clock demonstrates a short-term stability of 4.1 × 10-12 τ-1/2. The five-day Allan standard deviation reaches 7.7 × 10-15.

Co-inhibition of HSP70/HSP90 synergistically sensitizes nasopharyngeal carcinoma cells to thermotherapy.

The upregulation of both HSP70 and HSP90 frequently compromises the effects of thermotherapy. The co-inhibition of HSP70/HSP90 may be preferable to enhance the effects of thermotherapy on nasopharyngeal carcinoma cells. The changes of HSP70 and HSP90 were detected after thermotherapy in human nasopharyngeal cancer cell HNE1. 17-Dimethylaminoethylamino-17-demethoxygeldanamycin (17-DMAG) and quercetin were used to inhibit the activity of HSP90 and HSP70. The enhanced effects were evaluated in vitro and in vivo. Both HSP70 and HSP90 were upregulated promptly in HNE1 after thermotherapy. Single inhibition of HSP70 resulted in overexpression and delayed descent of HSP90. The co-inhibition of HSP70/HSP90 with quercetin plus 17-DMAG significantly increased apoptosis in hyperthermia-treated HNE1 cells both in vitro and in vivo. The co-inhibition of HSP70/HSP90 synergistically sensitizes nasopharyngeal carcinoma cells to hyperthermia.

[In vitro study of expression and effects of HSP70/HSP90 in nasopharyngeal carcinoma cells after thermotherapy].

OBJECTIVE: To investigate the changes and effects of HSP70/HSP90 of in nasopharyngeal carcinoma cells HNE1 after thermotherapy. METHODS: HNE1 cells were incubated at 42 degrees C for 2 h. The changes of mRNA and protein level of HSP70/HSP90 were detected by real-time PCR and western-blot at different intervals. HNE1 cells were pretreated with quercetin, geldanamycin or quercetin plus geldanamycin, respectively, before heat treatment. Flow cytometry assay was applied to determine the apoptosis of HNE1 cells before thermotherapy and at 2 h, 4 h, 6 h, 8 h, 12 h and 24 h after thermotherapy. RESULTS: HSP70/HSP90 expression was up regulated at 2 h, reached to its peak at 4 h, descended at 8 h and returned to the normal level at 24 h after thermotherapy. The inhibition of HSP70 through quercetin induced up-regulation and delayed descent of HSP90. Combined pretreatment with quercetin and geldanamycin could significantly induce HNE1 apoptosis when compared with pretreatment with quercetin or geldanamycin alone (P<0.05). CONCLUSION: HSP70/HSP90 expression in HNE1 up regulated promptly after thermotherapy. Inhibition of expression and activity of HSP70/HSP90 before thermotherapy can increase sensitivity of the tumor cell to heat treatment.

[Expression and significance of the cyclin E in laryngeal carcinomas].

OBJECTIVE: To investigate the clinicopathological significance of the cyclin E expression in laryngeal squamous cell carcinomas (LSCCs). METHOD: The expression of cyclin E was detected by immunohistochemistry method in 50 cases of LSCCs, 20 cases of dysplastic squamous epithelium and 10 polyps of vocal cord. RESULT: The positive expression of cyclin E was localized in the nuclei of cells. The positive rate of cyclin E protein in LSCCs, dysplastic squamous epithelium and polyps of vocal cord was 10% (1/10), 15% (3/20), 6% (3/50), respectively. There's no significant difference between them. While the expression of cyclin E in laryngeal cancer stromal vascular endothelial cells was significantly related with clinical stage and lymph node metastasis (P<0.01). CONCLUSION: In LSCCs, the expression of cyclin E has non-specificity, probably it has no participate the malignant transform events of laryngeal cancer cells. However, cyclin E is sensitive to vasculogenesis relatively; the positive expression of cyclin E may evaluate the malignant phase of LSCCs indirectly.

[The comparison of polymerase chain reaction and standard to fungi].

OBJECTIVE: The aim of this study was to compare the sensitivity of conventional culture and PCR method. METHOD: DNA samples were collected from the sinus of 20 patients with chronic sinusitis and 18 patients diagnosed as fungal sinusitis clinically. Fungal specific PCR analysis and standard culture were performed on every sample. chi2 analysis was used to determine the statistical differences between groups. RESULT: Fungal DNA were detected in 78% of patients with fungal sinusitis and 5% of patients with chronic sinusitis in PCR analysis, while the positive rate were 44% and 0% in standard cultures respectively. CONCLUSION: PCR is more rapid and sensitive than nasal swab culture in detecting the fungi in sinus mucosa. Our study suggests that it is an efficient method in diagnosis of fungal sinusitis.

[Vascular cell adhesion molecule-1, eotaxin and vascular endothelial growth factor in nasal polyps after endoscopic surgery].

OBJECTIVE: To study the different expression of VCAM-1, eotaxin and VEGF in nasal polyp tissues and in the nasal mucosa of the operative cavity after endoscopic surgery and its significance. METHODS: Paraffin sections of nasal polyps and the nasal mucosa of the operative cavity were studied with immunohistochemical technique and HE staining. RESULTS: (1) Abundant eosinophils were observed in the nasal polyps, however, it was rarely seen in the nasal mucosa of the operative cavity (t = 2.891, P <0.05). (2) The positive expression of VCAM-1 and eotaxin was in nasal polyps and nasal mucosa of operative cavity, and both of the positive area were not statistically significant (t = - 2.051, P > 0.05), but their average density of light was decreased in the nasal mucosa of the operative cavity (t = 3.670, P = 0.05). The positive glandular of eotaxin were increased after endoscopic surgery (t = -2.899, P < 0.05). (3) Expression of VEGF was similar in both groups (t = - 0.037, 0.825, P > 0.05, respectively). CONCLUSIONS: (1) It is suggested that the nasal mucosa of the operative cavity was different from the nasal polyps. (2) The positive expression of VCAM-1 and eotaxin in the nasal mucosa of the operative cavity after endoscopic surgery indicates that eotaxin may up-regulate the expression of VCAM-1 in vessel endothelium and promote adhesion and migration of eosinophils, as a result, to lead to the recurrence of nasal polyps. The glandulous expression of eotaxin may play a key role in the early stage. (3) The expression of VEGF in nasal mucosa after surgery may contribute to the growth of blood vessel and induce increasing of vascular permeability and tissue edema. This may be an important factor in the process of nasal polyp recurrence.

[Analysis on mutations of GJB2 gene in Chinese population].

OBJECTIVE: To determine the prevalence and types of GJB2 mutations and to investigate the genetic mechanism in Chinese autosomal recessive deafness. METHODS: The subjects were four Chinese pedigrees (39 individuals) and 50 normal adults. GJB2 was amplified by PCR. The products were digested with restriction enzyme Apa I, then sequenced. RESULTS: Homozygous deletion C at position 232-235 of GJB2 (235delC),which resulted in frameshift mutation, was found in four affected individuals of two pedigrees; the compound heterozygous deletions (235delC/232G to A) were found in two affected individuals in one pedigree. One carrier with 235delC was found in normal controls (1% allele). Two kinds of polymorphisms 79G to A(V27I) and 3 41A to G(E114G) were found in both affected and normal controls. The frequencies of allele for 79G to A and 341A to G in normal controls were 30%, 21%, respectively. CONCLUSION: 235delC mutation of GJB2 was related with Chinese autosomal recessive deafness, and the 232G to A(Ala78Thr) missense mutation was found to be a novel mutation.

[A study on the expression of TGF-beta 1/T beta R II in laryngeal carcinoma].

OBJECTIVE: To explore the expression of TGF-beta 1/T beta R II in laryngeal carcinoma. METHOD: Immunohistochemical study using SP kit in 53 cases. RESULT: The expression of TGF-beta 1 was decreased in carcinoma tissues when compared with peri-cancer controls (P < 0.05). There wasn't difference in T beta R II expression when compared with peri cancer controls (P > 0.05). But it was correlated with the stage, differentiation and lymph node metastasis of laryngeal carcinoma. CONCLUSION: TGF-beta 1/T beta R II may involve in the histogenesis and development of laryngeal carcinoma. The decreased expression of TGF-beta 1/T beta R II may serve as an important molecular marker of laryngeal carcinoma.