A novel low-voltage quadrature voltage-controlled oscillator (QVCO) with voltage feedback to the input gate of a switching amplifier is proposed and implemented using the standard TSMC 0.18-mum CMOS ...1P6M process. The proposed circuit topology is made up of two low-voltage LC-tank VCOs, where the coupled QVCO is obtained using the transformer coupling technique. At the 0.7-V supply voltage, the output phase noise of the VCO is -124.9 dBc/Hz at 1-MHz offset frequency from the carrier frequency of 2.4GHz, and the figure of merit is -185.35dBc/Hz. Total power consumption is 5.18 mW. Tuning range is about 135 MHz while the control voltage was tuned from 0 to 0.7V
A new wide locking range injection-locked frequency divider (ILFD) using a standard 0.18-mum CMOS process is presented. The ILFD is based on a differential voltage controlled oscillator (VCO) with ...two embedded injection metal oxide semiconductor field effect transistors (MOSFETs) for coupling external signal to the resonators. The new VCO is composed of two single-ended VCOs coupled with cross-coupled MOSFETs and a transformer. Measurement results show that at the supply voltage of 1.5 V, the divider's free-running frequency is tunable from 5.85 to 6.17 GHz, and at the incident power of 0 dBm the locking range is about 7.1 GHz (65.4%), from the incident frequency 7.3 to 14.4 GHz. The ILFD has a record locking range percentage among published divide-by-2 .LC-tank ILFDs.
The adsorption of an acid dye from water onto pristine and HCl-activated montmorillonites in fixed beds was investigated. Experiments were carried out as a function of liquid flow rate, initial dye ...concentration, and bed height. The adsorption capacity of acid dye onto pristine clay could be largely improved when the clay was activated by HCl. A mass transfer model that involves only two parameters,
τ (50% breakthrough time) and
k (adsorption rate constant), was proposed. This model could satisfactorily describe the measured breakthrough curves of acid dye in fixed beds (standard deviation <6%). It was shown that the value of
τ decreased with increasing liquid flow rate. The effect of the type of clay (pristine, acid-activated) on the values of
k,
τ, and adsorption capacity was discussed, and the application potential of acid-activated clay for adsorption removal of acid dye from water was also demonstrated.
Lee CH, Hsieh MJ, Chang SH, et al. Int J Nano.2019;14:7503-7513. The authors noticed a mistake in the published paperwhich was overlooked during the revision stages. On page 7511, in the ...Acknowledgments section, thesentence "... Chang Gung Memorial Hospital (ContractNo. CMRPG3G1291) for financially supporting thisresearch." should read "... Chang Gung MemorialHospital (Contract No. CMRPG3G1291 andCMRPG3G1292) for financially supporting thisresearch." The authors apologize for this oversight.Read the original article
Fixed bed removal of equimolar metal ions (Co
2+, Ni
2+, Mn
2+, Sr
2+) from aqueous solutions using a strong-acid resin was examined. The solution contained a water-soluble complexing agent including ...ethylenediaminetetraacetic acid, nitrilotriacetic acid, and citric acid. Experiments were performed under different solution pH and molar concentration ratios of complexing agent to the total metals. It was shown from batch studies that the equilibrium exchange of metals and the resin mainly depended on solution pH, and partly on the type of complexing agent used. A mass transfer model was proposed to describe the breakthrough curves of the resin bed, which contained two parameters (
τ and
k) estimated from the observed breakthrough data. The calculated breakthrough curves agreed well with the measured ones (standard deviation <6%). In fixed bed tests at low pH (=2), the type of complexing agent had little effect on the breakthrough data. For a given complexing agent, the metal with a larger overall formation constant (
K
f) showed a smaller exchange capacity. For a given metal ion, the complexing agent with a larger
K
f also revealed a smaller exchange capacity.
This letter proposes a wide locking range injection locked frequency divider (ILFD) and describes the operation principle of the ILFD. The circuit is made of a dual band two-stage differential ...complementary metal-oxide-semiconductor (CMOS) ring oscillator and is based on MOS switches directly coupled to the differential outputs of the ring oscillator. The divide-by-two ILFD can provide wide locking range and the measurement results show that at the supply voltage of 1.8-V, the divider free-running frequencies are 1.36GHz and 2.3GHz, and at the incident power of 0dBm, the locking range is about 1.75GHz from the incident frequency 1.9GHz to 3.65GHz at low band and 2.55GHz from 2.95GHz to 5.5GHz at high band
Background: The activation of an enzyme, inducible nitric oxide synthase (iNOS), catalyzes the production of endogenous nitric oxide (NO). NO, in turn, is associated with cell death, suppression of ...tumor development, and inhibition of metastasis of murine melanoma cells. Moreover, the in vivo induction of iNOS is associated with regression of established hepatic metastases. Whether this regression required the activation of the iNOS gene in every tumor cell or whether NO-producing tumor cells can also kill bystander (neighboring) cells has been previously unknown. Purpose: The goal of this study was to determine whether cells producing NO and then undergoing autolysis can also kill bystander cells in vitro and in vivo. Methods: Murine K-1735 C4.parental (C4.P) melanoma cells were transfected with the functional iNOS gene (transfectant denoted as C4.L8) or with a control truncated-nonfunctional iNOS gene (transfectant denoted as C4.S2). NO-mediated cytolysis and bystander cell killing were determined in vitro and in vivo. Results: Only the functional iNOS-transfected C4.L8 cells produced NO and underwent autolysis. C4.L8 cells also produced statistically significant lysis of iNOS-negative C4.P cells. This lysis was suppressed by the specific iNOS inhibitor NG-methyl-L-arginine. NO-producing C4.L8 cells and control C4.P or C4.S2 cells were injected subcutaneously into syngeneic C3H/HeN mice. Control C4.P and C4.S2 cells produced rapidly growing subcutaneous tumors, whereas C4.L8 cells did not. The mixture of C4.P and C4.S2 cells (1:5 ratio) produced rapidly growing subcutaneous tumors, whereas the mixture of C4.P and C4.L8.5 cells (1:5 ratio) produced slow-growing tumors. The subcutaneous growth of C4.P cells was not affected by C4.L8.5 cells injected subcutaneously at a distant site. Mixtures of C4.P cells labeled with 125Iiododeoxyuridine and C4.L8 cells (NO producing) or C4.S2 cells (control) were injected subcutaneously. The survival rate of the radiolabeled cells indicated that the NOproducing C4.L8.5 cells lysed the bystander C4.P cells. Conclusion: The production of high-level endogenous NO causes autolysis in tumor cells and lysis of bystander cells under in vitro and in vivo conditions. Implications: NO-mediated cell killing does not require transfection of genes into every cell in a neoplasm.
The high lifetime risk of vascular disease is one of the important issues that plague patients with diabetes mellitus. Systemic oral vildagliptin administration favors endothelial recovery and ...inhibits smooth muscle cell (SMC) proliferation. However, the localized release of vildagliptin in the diabetic vessel damage has seldom been investigated.
In this work, nanofiber-eluting stents that loaded with vildagliptin, a dipeptidyl peptidase-4 enzyme (DPP-4) inhibitor, was fabricated to treat diabetic vascular disease. To prepare nanofibers, the poly (D,L)-lactide-co-glycolide (PLGA) and vildagliptin were mixed using hexafluoroisopropanol and electrospinning process. In vitro and in vivo release rates of the vildagliptin were characterized using high-performance liquid chromatography.
Effective vildagliptin concentrations were delivered for more than 28 days from the nanofibrous membranes coating on the surface of the stents in vitro and in vivo. The vildagliptin-eluting PLGA membranes greatly accelerated the recovery of diabetic endothelia and reduced SMC hyperplasia. The type I collagen content of the diabetic vascular intimal area that was treated by vildagliptin-eluting stents was lower than that of the non-vildagliptin-eluting group.
The experimental results revealed that stenting with vildagliptin-eluting PLGA membranes could potentially promote healing for diabetic arterial diseases.
Previous suicide behavior predicts future suicide risk. Studies of suicide repetition are important for suicide prevention. This study examined the clinical characteristics and psychiatric ...comorbidities of pesticide self-harm as associated with suicide attempt repetition status.
This retrospective, observational study included patients admitted to a medical center in northern Taiwan between 2000 and 2015 following suicide attempts by pesticide. Diagnoses were made by a consultation-liaison psychiatry team based on the DSM IV-TR criteria. Independent samples
-test was used to analyze the quantitative variables and Pearson's Chi-squared test with a Bonferroni adjustment for categorical variables. Univariate binary logistic regression analysis was conducted to determine the predictors for repeated suicide attempt and multivariate binary logistic regression analysis to identify significant associated factors.
Among 151 patients, organophosphate pesticides were the most used (80.8%). The average age was 52.9±17.2 years. Most patients were married males from rural areas, with depressive disorder most often diagnosed (40.4%). Nearly one-third of them were suicide repeaters (n=43, 28.5%); these patients were less likely to be married (53.5%, p=0.001), had previously used psychiatric services (72.1%, p<0.001) and chose complex suicide (46.5%, p=0.014) more often compared to nonrepeaters. No significant differences were found between repeaters and nonrepeaters regarding psychiatric comorbidities. Multivariate logistic regression analysis revealed that marital status (odds ratio: 2.916, 95% confidence interval: 1.234-6.891, p=0.015) and previous psychiatric services usage (odds ratio: 6.897, 95% confidence interval: 3.012-15.625, p<0.001) were significant risk factors associated with suicide repetition.
Pesticide suicide repeaters were characterized by less likely to be married and more likely to use psychiatric services before suicide attempts. These features help ensuring that the needs of people who have made a suicide attempt are addressed, and it reduces the likelihood of repetition.
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