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In this work, we investigate, for the first time, a low-phase noise and wide-tuning range voltage-controlled surface acoustic wave oscillator (VCSO) based on a lithium niobate on sapphire (LNOS) low-loss acoustic delay line (ADL). The thin-film LN/SiO2 bilayer acoustic waveguide, together with the single-phase unidirectional transducer (SPUDT) design, is key to attaining low insertion loss (IL) by enhancing the energy confinement and directionality. Based on a high performance ADL with an IL of only 5.2 dB, a fractional bandwidth (FBW) of 5.38%, and a group delay of 110 ns, the VCSO is implemented by commercially available circuit components using a series-resonant topology. The LNOS ADL oscillator operates at 888 MHz, showcasing a low phase noise of -94.1 dBc/Hz at 1-kHz offset and a root-mean-square (RMS) jitter of only 30.26 fs (integrated from 12 kHz to 20 MHz) while only consuming 16 mA of supply current. Featuring a wide frequency tuning range of 6,630 ppm, the proposed VCSO is a promising low-noise, low-power, high-frequency timing device for emerging applications.

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Abstract-The need for wide-band radio frequency front ends (RFFE) with next-generation wireless protocols highlights the importance of electromechanical coupling kpff2. The hetero acoustic layered (HAL) surface acoustic wave (SAW) resonator with aluminum (Al) electrodes has shown superior performance compared to conventional SAW devices. Despite gold (Au) having excellent conductivity and stable properties, its high acoustic absorption and low phase velocity have made it less favorable for electrodes. This work demonstrates that high-performance shear horizontal (SH)-SAW resonators can be fabricated on the lithium niobate-on-insulator (LNOI) platform using a setup specifically designed for an Au electrodes. Experimental validation shows that the device achieves a high quality factor (Q) over 870, excellent keff2 up to 40%, and operates around 765 MHz. Unwanted transverse spurious modes are suppressed through adequate electrode design, and the temperature stability of LNOI SH-SAW with Au electrodes is discussed. This study highlights gold's potential as an electrode material for high keff2, clean spectrum, and wideband applications.

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In this study, we investigate the dispersive behavior of the electromechanical coupling coefficient ( [Formula: see text]) for shear-horizontal (SH) and Rayleigh surface acoustic wave (SAW) modes in a YX-LiNbO3 (LN)/SiO2/Si substrate across various wavelengths. Due to the difference in velocity dispersion between the SH and Rayleigh modes, mode coupling can be observed when these two modes operate at closely proximate frequencies, leading to a notable variation in their [Formula: see text]. With a careful design, SH and Rayleigh modes can be tuned to achieve a mode-decoupling state for enhancing [Formula: see text] of the SH-SAW and suppressing the presence of the Rayleigh mode in YX-LN/SiO2/Si. Consequently, a series of proof-of-concept SH-SAW resonators with wavelengths ( λ ) ranging from 1.6 to [Formula: see text] are fabricated. The optimized resonator with a λ of [Formula: see text] exhibits a resonant frequency of 1.064 GHz, an effective [Formula: see text] of 47.7%, a maximum Bode- Q of around 900, and an 18-dB rejection of spurious modes spanning from 0.5 to 3 GHz, without the presence of the Rayleigh mode.

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The low propagation loss of electromagnetic radiation below 1 MHz offers significant opportunities for low power, long range communication systems to meet growing demand for Internet of Things applications. However, the fundamental reduction in efficiency as antenna size decreases below a wavelength (30 m at 1 MHz) has made portable communication systems in the very low frequency (VLF: 3-30 kHz) and low frequency (30-300 kHz) ranges impractical for decades. A paradigm shift to piezoelectric antennas utilizing strain-driven currents at resonant wavelengths up to five orders of magnitude smaller than electrical antennas offers the promise for orders of magnitude efficiency improvement over the electrical state-of-the-art. This work demonstrates a lead zirconate titanate transmitter > 6000 times more efficient than a comparably sized electrical antenna and capable of bit rates up to 60 bit/s. Detailed analysis of design parameters offers a roadmap for significant future improvement in both radiation efficiency and data rate.

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We present the first group of GHz low-loss acoustic radio frequency (RF) couplers using the fundamental symmetric (S0) mode in X-cut lithium niobate thin films. The demonstrated multistrip couplers (MSCs) significantly surpass the insertion loss (IL) and the operating frequency of the previous works in more compact structures, thanks to the large electromechanical coupling and low loss of S0 in lithium niobate. The design space of S0 MSCs is first explored. Devices with different coupling factors are fabricated using different numbers of strips. Based on the S0 testbed with an IL of 4.5 dB at 1 GHz, the hybrid coupler shows an IL of 7.5 dB, while the track changer shows an IL of 5.1 dB, over a 3-dB fractional bandwidth of 8%. Couplers at different frequencies (between 0.75 and 1.55 GHz) are also investigated. Upon further optimizations, the S0 MSC platform can potentially enable low-loss wideband signal processing functions toward an RF acoustic component kit.

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We present the first group of GHz broadband SH0 mode acoustic delay lines (ADLs). The implemented ADLs adopt unidirectional transducer designs in a suspended X-cut lithium niobate thin film. The design space of the SH0 mode ADLs at GHz is first theoretically investigated, showing that the large coupling and sufficient spectral clearance to adjacent modes collectively enable the broadband performance of SH0 delay lines. The fabricated devices show 3-dB fractional bandwidth ranging from 4% to 34.3% insertion loss between 3.4 and 11.3 dB. Multiple delay lines have been demonstrated with center frequencies from 0.7 to 1.2 GHz, showing great frequency scalability. The propagation characteristics of SH0 in lithium niobate thin film are experimentally extracted. The demonstrated ADLs can potentially facilitate broadband signal processing applications.

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We present the first group of gigahertz S0 mode low loss and wideband acoustic delay lines (ADLs). The ADLs use a single-phase unidirectional transducers (SPUDT) design to launch and propagate the S0 mode in an X-cut lithium niobate thin film with large electromechanical coupling and low damping. In this work, the theoretical performance bounds of S0 mode ADLs are first investigated, significantly surpassing those in state-of-the-art. The design tradeoffs of S0 mode ADLs, when scaled to the gigahertz frequency range, are also discussed. The fabricated miniature ADLs show a fractional bandwidth (FBW) of 4% and a minimum insertion loss (IL) of 3.2 dB, outperforming the incumbent surface acoustic wave (SAW) counterparts, and covering a wide range of delays from 20 to 900 ns for digitally addressable delay synthesis. Multiple ADLs with center frequencies from 0.9 to 2 GHz have been demonstrated, underscoring their great frequency scalability. The propagation properties of S0 waves in lithium niobate at the gigahertz range are experimentally extracted. The demonstrated ADLs can potentially enable wide-range and high-resolution delay synthesis that is highly sought after for the self-interference cancellation in full-duplex radios.

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<p><b>OBJECTIVE</b>To investigate the significance of H3K27me3 and its methyltransferase EZH2 in predicting the short-term and long-term outcome of newly diagnosed patients with diffuse large B-cell lymphoma (DLBCL).</p><p><b>METHODS</b>The paraffin wax speciments of 102 DLBCL patients in Fujian Medical University Cancer Hospital were collected. The expression of H3K27me3, EZH2 and BCL-2 protein were detected using tissue array made by tissue microarray(TMA) technique and immunohistochemistry method. The evaluation data after clinical treatment and follow-up results were collected and combined with expression levels of H3K27me3, EZH2 and BCL-2 detected by tissue array, then on the basis of these data, the survival of patients was analyzed by Kaplan-Meier method, the correlation of EZH2 with H3K27me3 and BCL-2 was analyzed by pearson correlation test, the correlation of above mentioned indicators with different therapeutic efficacy was analyzed by spearman correlation test. The relationship of H3K27me3 and EZH2 expression as well as co-expression of H3K27me3 and EZH2 with the therapeutic efficacy and prognosis of patients were compared.</p><p><b>RESULTS</b>A total of 61.8% patients showed EZH2 high expression which positively correlated with high expression of H3K27me3 and BCL-2. The complete remission (CR) and overall remission (OR) rates in H3K27me3 high expression and co-expression of H3K27me3 EZH2 groups were lower than those in low expression groups (P<0.001), moreover OS and PFS rates also were lower than those in low expression (P<0.001). In the RCHOP subgroup, the patients with EZH2 low expression showed significantly better CR, OR OS and PFS in comparison with those of patients with higher expression (P=0.003,P=0.019).</p><p><b>CONCLUSION</b>Part of DLBCL patients with H3K27me3 high expression or coexpression of both H3K27me3 and EZH2 exhibit a worse prognosis in comparison with those patients with H3K27me3 low expression or without coexpression. The patients with EZH2 low expression usually responde well to RCHOP regimen in the short-term or long-term survival.</p>

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A differentially piezoresistive (piezo-R) readout proposed for single-crystal-silicon (SCS) microelectromechanical systems (MEMS) resonators is implemented in a foundrybased resonator platform, demonstrating effective feedthrough cancellation using just simple piezoresistors from the resonator supports while maximizing their capacitively transduced driving areas. The SCS resonators are fabricated by a CMOS foundry using an SOI-MEMS technology together with a polysilicon refill process. A high electromechanical coupling coefficient is attained by the use of 50-nm transducer gap spacing. Moreover, a vacuum package of the fabricated resonators is carried out through wafer-level bonding process. In this work, the corner supporting beams of the resonator serve not only mechanical supports but also piezoresistors for detecting the motional signal, hence substantially simplifying the overall resonator design to realize the piezo-R sensing. In addition, the fabricated resonators are capable of either capacitive sensing or piezo-R detection under the same capacitive drive. To mitigate feedthrough signals from parasitics, a differential measurement configuration of the piezo-R transduction is implemented in this work, featuring more than 30-dB improvement on the feedthrough level as compared with the single-ended piezo-R counterpart and purely capacitive sensing readout. Furthermore, the high-Q design of the mechanical supports is also investigated, offering Q more than 10 000 with efficient piezo-R transduction for MEMS resonators.

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Objective To evaluate the dietary arsenic intake level among residents in Hangzhou city,and to provide scientific basis for further food safety assessment.Methods A stratified multi -stage cluster sampling method was performed,and a total of 1 744 subjects were enrolled.Total diet survey was conducted to collect food consumption data through both food -weighting and recording during 3 consecutive days.Representative mixed food samples were prepared for total arsenic (tAs)detecting by using inductively coupled plasma -mass spectrometry (ICP -MS).Daily tAs and weekly presumptive inorganic arsenic (p -inAs)intakes were calculated and compared with corresponding tolerable limit values.Results The medians of dietary tAs and p -inAs intakes were 1 .4 μg/kgbw/d and 3.0 μg/kgbw/week,which accounted for 2.8% and 20.2% of corresponding former TDMI /PTWI,respectively.The tAs and p -inAs intake (1 .6 μg/kg·bw/d and 3.5 μg/kg·bw/week,respectively)in the age group of <1 8 years were significantly higher than that of other age groups (Z =-7.577 ~-2.91 7,P <0.01 ).The mainly source of individual dietary arsenic intakes was cereal foods.Conclusion The dietary intake of tAs and p -inAs are safe,but more attention should be paid to juveniles for the dietary intakes of tAs and p -inAs .

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Background Diabetic retinopathy (DR) leads to blindness because of the retinal angiogenesis caused by the ischemia of retina.Vascular endothelial growth inhibitor (VEGI) is a recently identified anti-angiogenic cytokine,which can suppress endothelial cell proliferation and angiogenesis.Objective The aim of this study was to detect the change of serum and vitreous VEGI/TL1A and its relative cytokines in patients with DR.Methods A non-randomized controlled clinical trial was performed.Fifty-five DR patients were enrolled in Tianjin Medical University General Hospital from November 2012 to March 2013 with the informed consent.The patients were divided into non-proliferative DR (NPDR) group (20 cases) and PDR group (35 cases).Eleven cataract patients served as normal control group,and 15 patients with diabetic mellitus (DM) were included as DM group.The demography was matched among the groups,but the course of DM and the blood glucose level were elevated in the PDR group and the DM group compared with DR group (all at P＜0.05).We collected the serum of all the patients above.Another 23 PDR patients (25 eyes) were enrolled in Tianjin Medical University General Hospital from November 2012 to March 2013 with the informed consent and served as PDR group,healthy corpse's eyes (n=7) as control group,the patients were assigned to the retinal photocoagulation group,surgery group and photocoagulation +surgery group according to different treatment procedures.Vitreous samples were collected during the progress of vitrectomy.TL1A/VEGI 251,VEGF,TNF-α,IL-1β and NF-κB p65 concentrations in the serum and vitreous specimens were detected using ELISA.The differences of serum and vitreous TL1A/VEGI 251,VEGF,TNF-α,IL-1β and NF-κB p65 in various groups were statistically analyzed by ANOVA and independent sample t test,respectively.The correlation between TL1A/VEGI 251 and VEGF,TNF-α,IL-1β,NF-κB p65 were calculated by Pearson correlation analysis.Results TL1A/VEGI 251 concentration was elevated in the DM group,NPDR group and PDR group compared with the normal control group,with significant difference among the 4 group (F =27.431,P =0.009),and TL1A/VEGI 251 concentration was higher in the PDR group than that in the DM group or the NPDR group (P＜0.05).VEGF,TNF-α,IL-1 β and NF-κB p65 concentrations in serum were increased in the PDR group in comparison with the DM group,NPDR group and the normal control group (P＜0.05).However,no significant difference among the DM group,NPDR group and the normal control group (P＞0.05).Serum TL1A/VEGI 251 concentration was significant correlated with VEGF,TNF-α,IL-1β and NF-κB p65 concentration (r=0.951,0.951,0.851,0.944,all at P＜0.01).Vitreous TL1A/VEGI 251,VEGF,TNF-α,IL-1 β concentrations were ascended in the PDR group compared with the normal control group (P =0.024,0.001,0.000,0.037),but there was no significantly difference in vitreous NF-κB p65 concentration between the two groups (P =0.073).Vitreous TL1A/VEGI 251 concentrations declined in the retinal photocoagulation group and the surgery group compared with the normal group (all at P＜ 0.05),and significant positive correlations were found between vitreous TL1A/VEGI 251 concentration and VEGF or TNF-α concentration (r =0.675,0.950,P ＜ 0.01) ;while Pearson correlation coefficient was not statistically significant between vitreous TL1A/VEGI 251 concentration and IL-1β or NF-κB p65 concentration (r=0.233,0.318,P＞0.05).Conclusions VEGI is involved in the pathogenesis of DR,and it interacts with VEGF,TNF-α,IL-1β and NF-κB to affect the development of DR.These results provide a new clue for the further study of DR.

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Integrated CMOS-MEMS free-free beam resonator arrays operated in a standard two-port electrical configuration with low motional impedance and high power handling capability, centered at 10.5 MHz, have been demonstrated using the combination of pull-in gap reduction mechanism and mechanically coupled array design. The mechanical links (i.e., coupling elements) using short stubs connect each constituent resonator of an array to its adjacent ones at the high-velocity vibrating locations to accentuate the desired mode and reject all other spurious modes. A single second-mode free-free beam resonator with quality factor Q > 2200 and motional impedance R(m) < 150 kΩ has been used to achieve mechanically coupled resonator arrays in this work. In array design, a 9-resonator array has been experimentally characterized to have performance improvement of approximately 10× on motional impedance and power handling as compared with that of a single resonator. In addition, the two-port electrical configuration is much preferred over a one-port configuration because of its low-feedthrough and high design flexibility for future oscillator and filter implementation.

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<p><b>OBJECTIVE</b>To observe the effects of Huoxue Jiedu Recipe (HJR) on the electroretinogram (ERG) and the expression of glial fibrillary acid protein (GFAP) in the retina tissue of early diabetic rats.</p><p><b>METHODS</b>The diabetic rat model was established using one single intraperitoneal injection of streptozotocin (STZ, 65 mg/kg). Then the modeled rats were randomly divided into 5 groups, i.e., the model group, the low dose HJR group (3.85 g/kg), the middle dose HJR group (7.70 g/kg), the high dose HJR group (15.40 g/kg), and the Western medicine treatment group (Calcium Dobesilate Capsule, 0.167 g/kg), 8 in each group. A normal control group consisting of 8 rats was also set up, which was given equal volume of distilled water by gastrogavage. All rats were medicated by gastrogavage for 20 weeks. The electroretinograph (ERG) was determined. The amplitudes of wave a and b (the maximal electric reaction for dark-adapted eyes), and the amplitude sum of the oscillatory potentials (OPs) were detected. The integral optical density (IOD), the protein and mRNA expression of GFAP were detected using immunohistochemical assay, Western blot, and fluorescent quantitative PCR.</p><p><b>RESULTS</b>Compared with the normal control group,the amplitudes of wave a, wave b, and OPs decreased in the model group (P<0.01). The protein and mRNA expressions of IOD and GFAP significantly increased (P<0.01). Compared with the model group, the amplitudes of wave b and OPs increased, and the protein and mRNA expressions of IOD and GFAP significantly decreased in each HJR group. The amplitude of wave a in the middle and high dose HJR groups increased. The amplitude of wave b increased and the IOD expression decreased in the Western medicine treatment group, showing statistical difference (P<0.05, P<0.01). There was no statistical difference in each index between the Western medicine treatment group and each HJR group.</p><p><b>CONCLUSION</b>HJR could attenuate the visual electrophysiological dysfunction in early diabetic rat, showing certain protection on retinal glial cells.</p>

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The prognosis of T-cell lymphoma (TCL) has been shown to be associated with the clinical characteristics of patients. However, there is little knowledge of whether genetic variations also affect the prognosis of TCL. This study investigated the associations between single nucleotide polymorphisms(SNPs) in tumor necrosis factor receptor superfamily(TNFRSF) genes and the survival of patients with TCL. A total of 38 tag SNPs in 18 TNFRSF genes were genotyped using Sequenom platform in 150 patients with TCL. Kaplan-Meier survival estimates were plotted and significance was assessed using log-rank tests. Cox proportional hazard models were used to analyze each of these 38 SNPs with adjustment for covariates that might influence patient survival, including sex and international prognostic Index score. Hazard ratios (HRs) and their 95% confidence intervals(CIs) were calculated. Among the 38 SNPs tested, 3 were significantly associated with the survival of patients with TCL. These SNPs were located at LTβR (rs3759333C>T) and TNFRSF17(rs2017662C>T and rs2071336C>T). The 5-year survival rates were significantly different among patients carrying different genotypes and the HRs for death between the different genotypes ranged from 0.45 to 2.46. These findings suggest that the SNPs in TNFRSF genes might be important determinants for the survival of TCL patients.

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<p><b>OBJECTIVE</b>To explore the association between HLA-DQA1 gene copy number polymorphisms and gastric cancer risk in Chinese population, and the interaction of those genes and environmental factors.</p><p><b>METHODS</b>The genotype of HLA-DQA1 gene copy number polymorphisms was determined in 343 patients with gastric cancer and 330 controls by quantitative polymerase chain reaction. Logistic regression model was used to evaluate the impact of this polymorphism on the risk of developing gastric cancer and the gene-environment interaction.</p><p><b>RESULTS</b>Compared with 0 copy of HLA-DQA1 gene carriers, the 2 copies of HLA-DQA1 gene carriers had a significantly increased risk of gastric cancer (OR = 1.87, 95%CI = 1.15 - 3.06, P = 0.012). Gene-environment interaction of HLA-DQA1 gene copy number polymorphisms and Helicobacter pylori infection significantly increased the risk of gastric cancer in a multiplicative manner, with an OR of 3.89 (95%CI = 1.75 - 8.57, P = 0.001).</p><p><b>CONCLUSIONS</b>HLA-DQA1 gene copy number polymorphism is associated with gastric cancer susceptibility, and there is a multiplicative gene-environment interaction between this polymorphism and Hp infection in the development of gastric cancer.</p>

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<p><b>OBJECTIVE</b>To study the diagnoses and treatments of small thyroid nodules (maximum diameter < 1 cm) with contralateral papillary thyroid microcarcinoma (PTMC).</p><p><b>METHODS</b>A total of 253 patients with unilateral PTMC and contralateral thyroid benign nodules identified by ultrasound before thyroidectomy was retrospectively analysed. All patients underwent near-total or total thyroidectomy. Chi-square test was used for univariate analysis and logistic regression test for multivariate analysis.</p><p><b>RESULTS</b>In 53 (20.9%) of 253 patients with unilateral PTMC, the contralateral thyroid benign nodules identified by ultrasound were confirmed pathologically as PTMC. Univariate analysis showed multifocality of the primary tumor and Hashimoto's thyroiditis were correlated with contralateral PTMC (χ(2) = 24.834, χ(2) = 5.182, P < 0.05). However, there were no significant differences for the existence of contralateral PTMC in age, sex, tumor size, capsule invasion, lymph node metastasis, the number of nodules and Tg-level. Multivariate analysis showed only multifocal PTMC was an independent predictive factor for contralateral PTMC (OR = 5.352, P < 0.05).</p><p><b>CONCLUSIONS</b>The patients with unilateral multifocal PTMC have a high rate of PTMC in contralateral small thyroid nodules. However, it is very difficulty to define by ultrasonography preoperatively. The total thyroidectomy maybe serve as a useful treatment.</p>

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<p><b>OBJECTIVE</b>To study the urinary protein patterns of nephropathy mice induced by dextran and the effects of aquesous extract of Fructus Corni (AEFC) and Radix Astragali (AERA).</p><p><b>METHOD</b>Nephropathy model was established by administrated with dextran to mice. Some of the dextran treated mice were given AERA (20 g x kg(-1) x d(-1)) as AERA group, other mice were given AEFC (10 g x kg(-1) x d(-1)) as AEFC group. Some of the dextran treated mice were given water as model group, some normal mice as normal control group. After a 12 weeks' treatment, 24 hour urine of four groups was collected, respectively. Each urinary sample was divided into two parts, one was non-concentrated urine sample, another was used as concentrated urine sample. Two kinds of urinary sample of four groups were analyzed with microfluidic chips on Agilent 2100 Bioanalyzer instrument.</p><p><b>RESULT</b>Each group's urinary protein patterns were obtained, more than 20 proteins were were detected. Compared with normal group, about five kinds of protein were found in urinary sample of model group, among which M > 43 x 10(3) proteins were increased. Compared with model group, significant treated-related protein's kind and quantitative changes in AERA treated group and AEFC group were found. Urinary protein kinds were reduced, especially certain the proteins (M > 50 x 10(3)) were significantly decreased approach to normal patterns. Non-concentrated urine samples' protein pattern mainly included were proteins (M=29, 32, 43, 52, 68, 76 x 10(3) and concentrated urine samples mainly included the proteins (M=22, 24, 32, 46 x 10(3)).</p><p><b>CONCLUSION</b>AERA and AEFC could reduce the urinary protein and made protein pattern different, which showed that radix astragali and fructus corni could play an important role in protecting renal function of nephropathy mice and finding the target protein markers related to AERA and AEFC effects on nephropathy mice.</p>

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