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For positive rank $r$ elliptic curves $E(\mathbb{Q})$, we employ ideal class pairings $$ E(\mathbb{Q})\times E_{-D}(\mathbb{Q}) \rightarrow \mathrm{CL}(-D), $$ for quadratic twists $E_{-D}(\mathbb{Q})$ with a suitable ``small $y$-height'' rational point, to obtain effective class number lower bounds. For the curves $E^{(a)}: \ y^2=x^3-a,$ with rank $r(a),$ this gives $$ h(-D) \geq \frac{1}{10}\cdot \frac{|E_{\mathrm{tor}}(\mathbb{Q})|}{\sqrt{R_{\mathbb{Q}}(E)}}\cdot \frac{\Gamma\left (\frac{r(a)}{2}+1\right)}{(4\pi)^{\frac{r(a)}{2}}} \cdot \frac{\log(D)^{\frac{r(a)}{2}}}{\log \log D}, $$ representing an improvement to the classical lower bound of Goldfeld, Gross and Zagier when $r(a)\geq 3$. We prove that the number of twists $E_{-D}^{(a)}(\mathbb{Q})$ with such a point (resp. with such a point and rank $\geq 2$ under the Parity Conjecture) is $\gg_{a,\varepsilon} X^{\frac{1}{2}-\varepsilon}.$ We give infinitely many cases where $r(a)\geq 6$. These results can be viewed as an analogue of the classical estimate of Gouv\^ea and Mazur for the number of rank $\geq 2$ quadratic twists, where in addition we obtain ``log-power'' improvements to the Goldfeld-Gross-Zagier class number lower bound., Comment: We correct minor typographical errors, including the formula in the abstract and equation (1.3)

We give an asymptotic formula for traces of weak Maass forms at CM points with an effective bound on the error term. Upon specializing to the modular j-function, we deduce such a result for traces of singular moduli. Due to work of Zagier, and Bringmann and Ono, these traces of weak Maass forms at CM points appear as Fourier coefficients of half-integral weight weakly holomorphic modular forms. Hence, our results give effective upper bounds for these Fourier coefficients.

Obesity is a major international health concern. Neighborhood greenery has been identified as a critical factor for promoting health in urban areas, due in part to its apparent role in facilitating healthy weight by promoting physical activity. However, studies have used diverse greenery measures and spatial analysis units to ascertain this relationship. This study examined associations between street greenery and weight status at the residential address level across 500–2000 m buffers in two climatically distinct communities, Phoenix, AZ, and Portland, OR. Greenery was measured using one-meter landcover data. Street greenery measures were designed to quantify the pedestrian environment along a gradient of suitability for promoting physical exercise. Weight status was defined by body mass index (BMI) calculated from weight and height information on driver’s license records. BMI values were dichotomized at 25 into overweight or obese vs. neither. Approximately 500,000 BMI values in Phoenix and 225,000 in Portland were modelled by community using logistic regression. Street tree cover was consistently protective for healthy weight status across all buffer sizes after adjusting for potential confounders. Herbaceous street cover showed protective associations in Phoenix but harmful associations in Portland. Every 10% increase in street tree cover within 2000 m was associated with 18% lower odds of being overweight or obese (adjusted odds ratio [AOR]: 0.82, 95% CI: 0.81 – 0.84 in Phoenix; 0.82, 95% CI: 0.81 – 0.83 in Portland). When compared to residents with less than 10% street tree cover within 2000 m, those with greater than 10% tree cover had at least 13% (AOR for Portland: 0.87, 95% CI: 0.81 – 0.92) lower odds of being overweight or obese. Findings support the importance of urban street trees in very different climates for facilitating healthy weight status. They can inform greenery management to prioritize vegetation type and allocation decisions in limited urban spaces.

Hole transporting layers (HTLs) have critical roles in the performance of perovskite solar cells. In this study, films of the vacuum-deposited small molecule of Tris[4-(5-phenylthiophene-2-yl)phenyl]amine (TPTPA) are demonstrated as efficient HTL materials for perovskite solar cells. The horizontal molecular stacking of the TPTPA neat film leads to the exceptionally high hole drift mobility of 7 × 10 −3 cm 2 V −1 s −1 , among the highest values observed in the organic molecular neat films. By doping with MoO 3 , a clear charge transfer state is formed and the hole mobility further increases to 3.6 × 10 −2 cm 2 V −1 s −1 . Both normal- and inverted-structured perovskite solar cells utilizing these HTLs are prepared and optimized; they show high power conversion efficiencies of 17–18%.

In this paper, we demonstrate that the performance of perovskite solar cells can be largely boosted with sub-nm pyridine-containing small-molecule electron interfacial layers. These vacuum-deposited sub-nm layers between perovskites and electron transport layers create a permanent dipole moment that improves the interfacial energy level alignment and facilitates a fast electron sweep-out. With these interfacial layers, the devices exhibit exceptional power conversion efficiencies up to 18.8%, a 25% increase compared to that of the one without the interfacial layer.

We demonstrate a simple but effective method to control the orientation of silver nanowires (AgNWs). Shear-flow-induced AgNW preferable orientation is realized by judiciously controlling the process parameters in the bar-coating method. This controllability of the NW direction enables the formation of AgNW cross-linking networks for transparent conductive electrode (TCE) applications. We experimentally demonstrate that the orthogonally weaved AgNW networks possess predominant advantages of lower percolation limit, higher transmission, and lower sheet resistance compared with the randomly orientated AgNW counterparts. The phenomenon is also confirmed with theoretical calculation by the Monte Carlo method. These high-quality AgNW TCEs exhibit a high transmittance of ∼94% with a sheet resistance of ∼20 Ω/sq, which meet the requirements of modern optoelectronic devices. Very efficient organic light-emitting diodes (OLEDs) and organic solar cells (OSCs) prepared by these AgNW TCEs are demonstrated. The OLED exhibits exceptionally high luminance efficiency, power efficacy, and external quantum efficiency of 92 cd/A, 111 lm/W, and 26.8%, respectively. The OSCs also deliver a high power conversion efficiency of up to 7.5%.

Introduction Urban vegetative cover provides a range of ecosystem services including contributions to human health and well-being. Urbanization exerts tremendous pressure on this natural resource, causing fragmentation and loss of urban greenspace. This study aimed to examine associations between vegetative cover fragmentation and physical activity and BMI at the county scale in the U.S. metropolitan statistical areas greater than 1 million in population. Methods National Land Cover Database 2006 and Behavioral Risk Factor Surveillance System 2008 provided land cover and human health data, respectively. Analyses were performed in 2013 at the county scale where the health data were reported. Spearman rank correlation and stepwise and hierarchical regression models were applied to estimate relationships between land cover and health variables. Results After controlling for median household income and race, greater forest edge density (β=0.272, p p p p Conclusions Forest land cover and some degree of fragmentation are associated with population physical activity. Future studies should examine how built environments and varying land cover configurations influence physical activity and weight status.

Two linear organic A–D–A molecules ( DTPT and DTPTT ) comprised of electron-donating (D) coplanar heteroacenes as core end-capping with electron-accepting (A) dicyanovinylene were investigated as electron donor materials in organic photovoltaic (OPV) applications. The photophysical and electrochemical properties of these two dyes were examined. The A–D–A configuration renders these two molecules to have intense and red-shifted absorption characteristics for better light-harvesting (higher photocurrent density), while retaining relatively low HOMO energy levels for keeping sufficiently high open circuit voltage ( V oc ) in OPV. The optical constants and molecular orientation of thin films were acquired with variable-angle spectroscopic ellipsometry (VASE). Due to the anisotropic behavior observed in thin film, these two organic donors were firstly adopted to combine with electron acceptor C 60 in a vacuum-processed planar heterojunction (PHJ) solar cells. The optimized DTPT -based PHJ device yielded a PCE of 3.01%, whereas the PHJ device based on DTPTT , delivered an inferior PCE of 1.70%. The exciton diffusion length extracted from spectrum-response modeling of PHJ devices is ∼5 nm and ∼4 nm for DTPT and DTPTT , respectively. Replacement of C 60 with C 70 for a better spectral response in 400–500 nm, planar-mixed heterojunction (PMHJ) SMOSCs without a thin donor layer in between the active layer and MoO 3 was found to produce optimum device results. The optimized DTPTT -based device showed a PCE of 3.02%, while the shorter counterpart DTPT delivered a PCE up to 5.64%.

Sedentary lifestyles contribute to many adverse health outcomes and pose concerns for public health worldwide. Studies show that road network design and greenery are critical, independent factors in supporting active lifestyles. Yet greenery along the road network has been insufficiently assessed. This study modelled individual weekly participation in active transportation (AT) using spatially refined measures of street versus overall neighborhood greenery in greater Milwaukee and Green Bay, Wisconsin, USA. Measures of AT (walking or biking for commutes or errands) were collected by the Survey of the Health of Wisconsin. Meter-scale landcover was used to estimate percent tree cover and aggregate greenery (tree and herbaceus cover combined) at increasing distances from each residence (n = 423) along neighborhood streets and in circular buffers. Street greenery metrics were designed to indicate the provision of ecosystem services, including shade and aesthetics, which promote physical activity by enhancing the safety and beauty of the publicly-accessible outdoor environment. Positive associations were consistently observed for street tree cover (e.g., adjusted odds ratio for a 10% increase in sidewalk tree cover within 500 m = 1.19; 95% CI: 1.02–1.40; and in street tree cover within 1250 m = 1.39; 95% CI: 1.09–1.79). Aggregate greenery was significant only in circular buffers, where it was negatively associated with AT. Sensitivity analysis revealed that herbaceous cover alone was consistently negatively associated with AT. Findings inform urban design to promote healthy lifestyles by distinguishing street tree cover as a positive factor in AT. Studies in additional geographic areas and causal designs are recommended.

Patients with chronic liver disease had lower serum concentrations 25-hydroxyvitamin D (25OHD). Glycine, a nonessential amino acid, exerts anti-inflammatory, cytoprotective, and immunomodulatory properties. This study aimed to establish a tandem mass spectrometry assay to measure 25OHD in guinea pigs serum and to investigate the effects of glycine against the liver damage induced by bile duct ligation (BDL).BDL was performed on male guinea pigs. Glycine, alanine, serine or tyrosine was given by intraperitoneal injection. The animals were sacrificed and examined at 7 and 14 days after BDL. Serum concentrations of total bilirubin and aminotransferase were measured. Serum concentrations of 25OHD2 and 25OHD3 were measured by API 5000 mass spectrometer. In addition, oxidative stress was assessed by serum ischemia-modified albumin (IMA) and hepatic malondialdehyde (MDA), and apoptosis by hepatic caspase 3 activities.Serum 25OHD concentrations were decreased around 50% in the BDL group at days 7 and 14 post ligation, compared to sham (mean 65.3 ng/ml, p0.005). Glycine but not other amino acid treatment blunted the reduced serum 25OHD (52.6 ng/ml, p0.05) resulting from BDL. The concentrations of 25OHD were negatively associated with concentrations of IMA (r=-0.305, p0.05) and caspase 3 (r=-0.562, p0.0001). At day-14 post ligation, glycine treatment also ameliorated liver damage indicated by serum AST (p0.005), ALT (p0.05) and hepatic caspase 3 activities (p0.05) and oxidative stress.Our results indicate that glycine may protect against BDL-induced liver injury through attenuation of oxidative stress, apoptosis and the vitamin D deficiency.

Statins are reported to alleviate renal fibrosis in animal models with ureteral obstruction. However, the molecular mechanism of this antifibrotic effect is still unclear. Pressure force is an important mechanism contributing to induction and progression of tubulointerstitial fibrogenesis in ureteric obstruction. In this study, we investigated the influence of rosuvastatin on pressure-induced fibrotic responses in rat renal tubular cells (NRK-52E). We established an in vitro pressure culture system to study pressure-induced fibrotic responses in NRK-52E cells. When NRK-52E cells were cultured in the pressure culture system, 60 mm Hg of pressure induced the expression of connective tissue growth factor (CTGF), transforming growth factor (TGF)-β, fibronectin, Smad3, and phospho-Smad3. Rosuvastatin significantly reduced these pressure-induced fibrotic responses at concentrations above 10 μM. Rosuvastatin also reduced the TGF-β-induced expression of fibronectin and CTGF in NRK-52E cells. Pretreatment with rosuvastatin significantly induced prostacyclin (PGI(2)) generation, but reduced pressure-induced prostaglandin E(2) (PGE(2)). PGI(2) synthase small interfering RNA (siRNA) transfection significantly inhibited rosuvastatin-induced peroxisome proliferator-activated receptor α activation. The blockage of peroxisome proliferator-activated receptor α by siRNA transfection reduced the inhibitory effect of rosuvastatin on pressure-induced fibrotic responses. N-[2-(cyclohexyloxy)-4-nitrophenyl]-methanesulfonamide (NS398), a specific inhibitor of cyclooxygenase-2, diminished pressure-induced PGE(2) generation, and also reduced pressure-induced fibrotic responses. Additionally, PGE(2) decreased the antifibrotic effect of rosuvastatin. In conclusion, rosuvastatin reduces pressure-induced fibrotic responses in renal tubular cells by enhancing the PGI(2)-peroxisome proliferator-activated receptor α pathway and reducing PGE(2) generation.

The light guide plate (LGP) is a part of a backlight module, which evenly spreads light sources in a liquid crystal display (LCD) to eliminate total reflection. Light is transmitted into the LGP, where it is reflected, scattered, and refracted due to the microstructure, which allows light to uniformly enter the panel. Therefore, the design of an LGP micro-structure and processing mode is important for light transmission in an LCD. This study used a CO 2 laser to fabricate a polymethyl methacrylate (PMMA) LGP, applied a Taguchi orthogonal array to set up the experiment, and utilized the data to establish a prediction system. Backpropagation (BP) neural network and the Levenberg–Marquardt (LM) algorithm were integrated to establish a prediction system for LGP processing by CO 2 laser, with the controlling factor as the input parameter, and quality characteristics as the output parameters. After learning and training the network, the prediction error rate of the system was controlled within 5%, demonstrating good predictive validity.

Background Frail older persons are at high risk of morbidity and mortality, and are characterized by body composition alterations. Serum testosterone, which regulates body composition, declines with age. We investigated the relation between serum testosterone level and physiological frailty in both older men and women. Methods This was a cross-sectional study of 108 adults 65 years old or older. Frailty status was determined by hand-grip strength, weight change, walking speed, exhaustion, and activity levels, and was classified as frail (3 or more deficits), pre-frail (1 or 2 deficits), or robust (no deficit) according to the Fried criteria. Serum total testosterone (TT) and sex-hormone-binding globulin were measured while free testosterone (FT) was estimated. Results Median (range) TT and FT were lower in frail than in pre-frail and robust men (TT: ( frail ) 15.7 [2.4–26.9] vs. ( pre - frail ) 19.4 [7.2–39.9] and ( robust ) 25.9 [13.2–35.2] nmol/L, P = 0.03; FT: 230.0 [35.9–299.0] vs. 272.0 [86.7–411.0] and 303.0 [267.0–396.0] pmol/L, P = 0.02) and women (TT: 0.31 [0.10–0.51] vs. 0.47 [0.14–1.55] and 0.45 [0.36–1.25] nmol/L, P = 0.02; FT: 4.59 [0.46–6.63] vs. 4.66 [1.57–15.10] and 6.65 [3.91–21.00] pmol/L, P = 0.03). After adjusting for age, comorbidities, body mass index, and serum albumin in ordinal logistic regression model, odds ratios of being frail were significantly higher for those participants whose TT and FT levels were in the lowest tertile compared to the highest tertile in men (TT: odds ratio [OR] 3.29, 95% confidence interval [CI] 1.14–9.50; FT: OR 3.44, 95% CI 1.05–11.22) and in women (TT: OR 6.69, 95% CI 1.84–24.31; FT: OR 4.86, 95% CI 1.31–18.08). Conclusions Low serum testosterone levels were independently associated with frailty in the elderly Taiwanese.

Information about park infrastructure such as trail networks is not only useful for visitors to plan trips that meet their own needs, but it is also important for park and open space managers to monitor their assets and direct trail use patterns to achieve management objectives. This study aims at applying and evaluating dynamic segmentation and network analysis techniques in a GIS to gather elevation data on trail routes and generate travel time and energy consumption information. The method was applied to a network of 16 trails in a well-visited forest recreational area in central Taiwan Island. Results show that it is feasible and efficient to use GIS methods to integrate multiple data sets and derive advanced trail information. Optimal routes based on the least time cost and the most energy cost were identified. Combining indoor, GIS-based and outdoor field work of trail surveys is likely to produce information that is reliable and useful for visitors and managers to make travel and management decisions.

This study used ultraviolet laser to perform the microcrystalline silicon thin film solar cell isolation scribing process, and applied the Taguchi method and an L18 orthogonal array to plan the experiment. The isolation scribing materials included ZnO:Al, AZO transparent conductive film with a thickness of 200 nm, microcrystalline silicon thin film at 38% crystallinity and of thickness of 500 nm, and the aluminum back contact layer with a thickness of 300 nm. The main objective was to ensure the success of isolation scribing. After laser scribing isolation, using the minimum scribing line width, the flattest trough bottom, and the minimum processing edge surface bumps as the quality characteristics, this study performed main effect analysis and applied the ANOVA (analysis of variance) theory of the Taguchi method to identify the single quality optimal parameter. It then employed the hierarchical structure of the AHP (analytic hierarchy process) theory to establish the positive contrast matrix. After consistency verification, global weight calculation, and priority sequencing, the optimal multi-attribute parameters were obtained. Finally, the experimental results were verified by a Taguchi confirmation experiment and confidence interval calculation. The minimum scribing line width of AZO (200 nm) was 45.6 μm, the minimum scribing line width of the microcrystalline silicon (at 38% crystallinity) was 50.63 μm and the minimum line width of the aluminum thin film (300 nm) was 30.96 μm. The confirmation experiment results were within the 95% confidence interval, verifying that using ultraviolet laser in the isolation scribing process for microcrystalline silicon thin film solar cell has high reproducibility.

Background Rebleeding occurs in 10% to 30% of bleeding ulcer patients receiving endoscopic epinephrine injection therapy. It remains unclear whether addition of a secondary clip therapy following epinephrine injection may reduce the rebleeding rate of high-risk bleeding ulcers. Objective To compare the efficacies of epinephrine injection alone and epinephrine injection combined with hemoclip therapy in treating high-risk bleeding ulcers. Design Prospective randomized controlled trial. Setting A medical center in Taiwan. Patients One hundred five bleeding ulcer patients with active spurting, oozing, nonbleeding visible vessels or adherent clots in ulcer bases. Interventions Endoscopic combination therapy (n = 52) or diluted epinephrine injection alone (n = 53). Main Outcome Measurements Initial hemostasis rates and recurrent bleeding rates. Results Initial hemostasis was achieved in 51 patients treated with combination therapy and 49 patients with epinephrine injection therapy (98% vs 92%, P = .18). Bleeding recurred in 2 patients in the combination therapy group and 11 patients in the epinephrine injection group (3.8% vs 21%, P = .008). Among the patients with rebleeding, repeated combination therapy was more effective than repeated injection therapy in achieving permanent hemostasis (100% vs 33%, P = .02). No patient required an emergency operation in the combination therapy group. However, 5 patients in the epinephrine injection group underwent emergency surgery to arrest bleeding (0% vs 9%, P = .023). Limitations Treatment outcome of endoscopic hemoclip therapy is related to the techniques of endoscopists. Conclusion Endoscopic combination therapy is superior to epinephrine injection alone in the treatment of high-risk bleeding ulcers.

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Background & Aims The generation of oxidative stress and transforming growth factor β1 (TGF-β1) production play important roles in liver fibrogenesis. We have previously shown that hepatitis C virus (HCV) increases hepatocyte TGF-β1 expression. However, the mechanisms by which this induction occurs have not been well studied. We explored the possibility that HCV infection regulates TGF-β1 expression through the generation of reactive oxygen species (ROS), which act through ≥1 of the p38 mitogen-activated protein kinase (MAPK), extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and nuclear factor κB (NFκB) signaling pathways to induce TGF-β1 expression. Methods We used small molecule inhibitors and short interfering RNAs to knock down these pathways to study the mechanism by which HCV regulates TGF-β1 production in the infectious JFH1 model. Results We demonstrated that HCV induces ROS and TGF-β1 expression. We further found that JFH1 induces the phosphorylation of p38MAPK, JNK, ERK, and NFκB. We also found that HCV-mediated TGF-β1 enhancement occurs through a ROS-induced and p38 MAPK, JNK, ERK1/2, NFκB-dependent pathway. Conclusions These findings provide further evidence to support the hypothesis that HCV enhances hepatic fibrosis progression through the generation of ROS and induction of TGF-β1. Strategies to limit the viral induction of oxidative stress appear to be warranted to inhibit fibrogenesis.