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This meta-analysis examined the predictive value of admission serum and urine carboxypeptidase-B activation peptide (CAPAP) in patients with severe acute pancreatitis. PubMed, Embase, and the Cochrane Library were searched for relevant studies published up to February 21, 2022. Seven studies (439 acute pancreatitis patients) were included. The summary sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), the area under the receiver operating characteristic curve (AUC) of admission serum CAPAP were 0.86 (95%CI: 0.76-0.93), 0.78 (95%CI: 0.68-0.85), 3.89 (95%CI: 2.56-5.91), 0.18 (95%CI: 0.09-0.33), 18.56 (95%CI: 6.99-49.30), and 0.90 (95%CI: 0.87-0.92), respectively; these values for admission urine CAPAP were 0.82 (95%CI: 0.50-0.95), 0.78 (95%CI: 0.68-0.86), 3.75 (95%CI: 2.40-5.85), 0.23 (95%CI: 0.07-0.79), 9.87 (95%CI: 3.71-26.22), and 0.84 (95%CI: 0.80-0.87), respectively. There were no significant differences between admission serum and urine CAPAP in sensitivity (1.05, 95%CI: 0.75-1.47; P = 0.781), specificity (1.00, 95%CI: 0.85-1.18; P = 1.000), PLR (1.04, 95%CI: 0.56-1.91; P = 0.906), NLR (0.78, 95%CI: 0.20-3.10; P = 0.727), and DOR (1.88, 95%CI: 0.47-7.49; P = 0.370). The AUC of serum CAPAP (1.07, 95%: 1.02-1.13; P = 0.007) was higher than that of urine CAPAP in predicting acute pancreatitis severity. Both admission serum and urine CAPAP had moderate predictive values for assessing the severity of acute pancreatitis. [ABSTRACT FROM AUTHOR]

Background • Obesity remains among one of the greatest health care threats facing today’s children and adolescents. Yoga has gained increased popularity in the United States and appears as a promising way to assist with weight loss and management in adults. However, research examining yoga programs targeting weight loss for children or adolescents are relatively scarce. Objective • The current study provided a systematic review of yoga-based interventions targeting weight loss among overweight or obese children and adolescents. Methodology • The authors conducted a systematic review of articles obtained from Alt HealthWatch, CINAHL, SPORTDiscus, PubMed, and Web of Science databases. Inclusion criteria were studies employed yoga as a primary component, targeted overweight or obese children or adolescents, measured body weight or BMI as an outcome, utilized any type of study design, and published in peer-reviewed journals in English language. Results • A total of nine studies met the inclusion criteria. Most studies were conducted in the United States (n=5), and implemented in the school setting (n = 5). Among studies reviewed, three were randomized controlled trials, and two were with the attrition rates approaching 50%. A majority of the interventions were able to facilitate weight loss and relevant behaviors. Conclusion • The impact of yoga interventions on child and adolescent obesity was small but meaningful. Some of the limitations include small sample sizes, lack of followup assessment after posttest, lack of control groups, lack of utilization of behavioral theories, and lack of intervention targeting disadvantaged populations. Future interventions utilizing randomized controlled trials with large sample sizes are needed to assess the impact of yoga on child and adolescent obesity. [ABSTRACT FROM AUTHOR]

Asian leaf-litter toads of the genus Leptobrachella represent charismatic anuran diversification with 80 species, of which 25 are from China. Recent new discoveries suggest that the diversity of this genus is underestimated. Here, we describe a new species of Leptobrachella, Leptobrachella bashaensis sp. nov. from the Basha Nature Reserve, Congjiang County, Guizhou Province, China. The new species is distinguished from its congeners by the following suite of morphological traits: small body size (SVL 22.9-25.6 mm in six adult males and 27.1 mm in one adult female); head longer than wide; dorsal skin slightly shagreened with small tubercles; creamy-white chest and belly with irregular black spots; distinct ventrolateral glands forming a white line; finger webbing and fringes absent; toe webbing rudimentary and lateral fringes narrow; iris bicolored with bright orange in upper half and silver in lower half; dorsal surface of tadpole head dark brown with small, brown, irregular spot, air sac-shaped bulges on both sides of body. The new species differs from all known congeners by an uncorrected p-distance of >5.3% of the 16S rRNA gene fragment examined, and the phylogenetic analysis clusters the new species with L. maoershanensis and L. laui. At present, the new species is only known from a small range of montane evergreen secondary forests in Basha Nature Reserve approximately 900 m elevation. Its natural history and conservation status are discussed. [ABSTRACT FROM AUTHOR]

This study investigates the feasibility of a relevance vector machine tuned with improved Manta-Ray foraging optimization (RVM-IMRFO) in predicting monthly pan evaporation using limited climatic input data (e.g. temperature). The accuracy of the RVM-IMRFO was evaluated by comparing it with RVM tuned by gray wolf optimization, RVM tuned with a whale optimization algorithm, and RVM tuned with Manta Ray foraging optimization concerning root mean square errors (RMSE), mean absolute errors (MAE), determination coefficient (R²) and Nash-Sutcliffe Efficiency (NSE) and new graphical inspection methods. The models were assessed using data acquired from two stations in China and data were divided into three equal parts. The models were tested using each data set. The application outcomes revealed that the proposed algorithm considerably improved the accuracy of a single RVM in monthly pan evaporation prediction by an average improvement in RMSE, MAE, R², and NSE as 27.65%, 27.53%, 8.40% and 8.63%, respectively. It is also found that the proposed algorithm showed significant dominance over others models with respect to improvement in overall mean values of RMSE, MAE, R², and NSE statistics from 34.7-38.2 to 18.2-19.5, 36.2-36.4 to 19.1-18.5, 12.5-13.8 to 3.6-3.7, and 12.4-14.6 to 3.6-3.9%, for both climatic stations, respectively. Importing extraterrestrial radiation and periodicity component (month number of the data) into the model inputs improved the prediction accuracy of the implemented models. The outcomes revealed that the RVM-IMRFO performed superior to the other methods in predicting monthly pan evaporation using only temperature data which is essential, especially in developing countries where other climatic data are missing or unavailable. The RVM model was also compared with standard multi-layer perceptron neural networks (MLPNN) and found that the first acts better than the latter in monthly pan evaporation prediction. [ABSTRACT FROM AUTHOR]

In the present study, the molecular mechanisms involved in the α-tomatine-induced apoptosis in human glioblastoma cell lines A172 and U-118 MG were investigated. Wright staining and ApopTag assays were conducted to confirm the apoptosis induced by α-tomatine treatment. Fura-2 assay determined an enhancement in free Ca2+ intracellularly, indicating the occurrence of Ca2+-dependent apoptosis induction. Western blot experiments were also performed to predict the apoptosis by measuring the changes in the Bax:Bcl-2 ratio. Increase of calpain activity triggered caspase-12 expression, which in turn further activated caspase-9. In addition, an increase in the ratio of Bax:Bcl-2 accounted for the mitochondrial release of cytochrome c into the cytosol for caspase-3 and caspase-9 activation. Elevated activity of calpain and caspase-3 yielded spectrin breakdown products with 145 and 120 kDa, respectively. Caspase-3 activation further cleaved the inhibitor of caspase activated DNase, while the apoptosis-inducing factor detected in the cytosol suggested that apoptosis was independent of caspase. The apoptosis induction was further supported by decreased expression levels of nuclear factor-κB and increased expression of the inhibitor of nuclear factor, IκBα. In conclusion, the presented experimental results revealed the stimulation of different molecular mechanisms for α-tomatine-mediated apoptosis in A172 and U-118 MG human glioblastoma cell lines. [ABSTRACT FROM AUTHOR]

Tapping mode (TM) atomic force microscopy (AFM) in a liquid environment is widely used to measure the contours of biological specimens. The TM triggers the AFM probe approximately at the resonant frequencies and controls the tip such that it periodically touches the specimen along the scanning path. The AFM probe and its tip produce a hydrodynamic pressure on the probe itself and press the specimen. The tip to specimen size ratio is known to affect the measurement accuracy of AFM, however, few studies have focused on the hydrodynamic pressure caused by the effects of specimen size. Such pressure affects the contour distortion of the biological specimen. In this study, a semi-analytical method is employed for a semicircular specimen to analyze the vorticity and pressure distributions for specimens of various sizes and at various tip locations. Changes in pressure distribution, fluid spin motion, and specimen deformation are identified as the tip approaches the specimen. The results indicate the following: the specimen surface experiences the highest pressure when the specimen diameter equals the tip width; the vorticity between tip and specimen is complex when the tip is close to the specimen center line; and the specimen inflates when the tip is aligned with the specimen center line. [ABSTRACT FROM AUTHOR]

Resistant HCV variants carrying NS5B S282T mutation confer reduced sensitivity to sofosbuvir, the sole marketed NS5B polymerase inhibitor. On the basis of the finding that 2'-α-F-2'-β-C-methylcytidine 5'-triphosphate (8) was more potent than sofosbuvir's active metabolite on inhibition of both wild-type and S282T mutant polymerase, a dual-prodrug approach has been established. Twenty-nine phosphoramidates with N4-modified cytosine were designed, synthesized, and evaluated for anti-HCV activity. The results showed that compounds 4c-4e and 4m (EC50 = 0.19-0.25 μM) exhibited comparable potency to that of sofosbuvir (EC50 = 0.15 μM) on inhibition of wild-type replicons. Notably, 4c (EC50 = 0.366 μM) was 1.5-fold more potent than sofosbuvir (EC50 = 0.589 μM) on inhibition of S282T mutant replicons. In vitro metabolic studies disclosed the possible metabolic pathways of 4c. The toxicity study results indicated a good safety profile of 4c. Together, 4c-4e and 4m hold promise for drug development for the treatment of HCV infection, especially the resistant variants with NS5B S282T mutation. [ABSTRACT FROM AUTHOR]

The effect of sludge biochars obtained at different temperatures on the adsorption of Cd(II) by loess in northwestern China was investigated using the batch equilibrium method. The results showed that the pseudo second-order kinetic model can describe the kinetics of Cd(II) adsorption on the sludge biocharamended loess very well. The adsorption of Cd(II) by loess reached equilibrium in 6h. However, with the addition of biochar, the adsorption time of the Cd(II) by loess decreased. In addition, the adsorption equilibrium time decreased significantly with increasing pyrolysis temperatures. When the pH increased from 2 to 7, the adsorption capacity of biochar-amended loess increased, while the adsorption capacity was in equilibrium or even slightly decreased in the pH range from 7 to 8. The Langmuir model can describe the adsorption isothermal behaviours of Cd(II) by biochar-amended loess. The adsorption capacity of biochar-amended loess samples for Cd(II) at 25°C follows the order of LSB700 (28.74 mg/g)>LSB500 (22.42 mg/g)>LSB300 (17.67 mg/g). The addition of sludge biochars can significantly improve the saturation adsorption capacity of loess for Cd(II). Therefore, the addition of sludge biochars can effectively improve the adsorption-immobilization capability of loess for Cd(II). [ABSTRACT FROM AUTHOR]

Knots can occur in biopolymers such as DNA and peptides. In our previous study, we systematically investigated the effects of intra-chain interactions on knots and found that long-range repulsions can surprisingly tighten knots. Here, we use this knowledge to trap a knot into tight conformations in Langevin dynamics simulations. By trapping, we mean that the free energy landscape with respect to the knot size exhibits a potential well around a small knot size in the presence of long-range repulsions, and this potential can well lead to long-lived tight knots when its depth is comparable to or larger than thermal energy. We tune the strength of intra-chain repulsion such that a knot is weakly trapped. Driven by thermal fluctuations, the knot can escape from the trap and is then re-trapped. We find that the knot switches between tight and loose conformations--referred to as "knot breathing". We use a Yukawa potential to model screened electrostatic interactions to explore the relevance of knot trapping and breathing in charged biopolymers. We determine the minimal screened length and the minimal strength of repulsion for knot trapping. We find that Coulomb-induced knot trapping is possible to occur in single-stranded DNA and peptides for normal ionic strengths. [ABSTRACT FROM AUTHOR]

Knots occur frequently in our daily life and also in long polymers. Studies of spontaneously occurring knots in a linear polymer have focused on their size and probabilities. In this work, we report counterintuitive phenomena about knot sizes and explain them by an analytic theory. Our simulations show that short-range intrachain attractions (repulsions) lead to shrinking (swelling) of knot sizes, trends which follow intuition. However, long-range attractions (repulsions) surprisingly lead to swelling (shrinking) of knot sizes. Such counterintuitive trends are because larger knots contain more interacting monomer pairs if the interaction range is larger than a critical value. The critical interaction range varies from a fraction of to multiple persistence lengths, and so the long-range interaction regime can be reached for DNA, peptide chains, or synthetic polymers under depletion attractions induced by colloids (e.g., proteins) or via Coulomb repulsions. Our results suggest that probabilities and sizes of knots can be controlled independently through adjusting the range and the strength of intrachain interactions. [ABSTRACT FROM AUTHOR]

Background: Hyperlipidemia is a common disease in China. Although 88.9 % of the Chinese population taking lipid-lowering medications has already used a statin, only 61.5 % of the population has reached the goal of low-density lipoprotein cholesterol. Thus, many patients in China seek help from Traditional Chinese Medicine. Yirui capsules are an innovative Chinese Medicine which are designed to improve the blood lipid state in patients with hyperlipidemia. However, there is still a lack of high-quality evidence from clinical trials to support the application. Therefore, we designed a clinical trial to evaluate the safety and efficacy of Yirui capsules for use by patients with hyperlipidemia.Methods/design: This is a multicenter, randomized, double-blinded, placebo-controlled trial. Based on lifestyle modification therapy, eligible patients will randomly be assigned to the Yirui capsule or the placebo group. The primary outcome is the percentage of participants who reach the goal of 30 % low-density lipoprotein cholesterol decline at treatment end-point. The secondary outcomes include the changes from baseline to treatment endpoint in low-density lipoprotein cholesterol, total cholesterol, triglyceride, high-density lipoprotein cholesterol, apolipoprotein A, apolipoprotein B, non-high-density lipoprotein cholesterol, MOS 36-Item Short-Form Health Survey scoring, total and individual item scoring of symptomatic grading and quantifying scale, and body mass index.Discussion: The main ingredients of the Yirui capsule are perilla oil, Folium Ginkgo (Yinxingye), Radix Salviae miltiorrhizae (Danshen), Fructus Crataegi (Shanzha), Rhizoma Alismatis (Zexie), and Radix Notoginseng (Sanqi), which are expected to improve the blood lipid state. This randomized placebo-controlled trial will comprehensively evaluate the effectiveness and safety of Yirui capsules against hyperlipidemia in the hope of providing a new adjunctive Chinese medicine option for clinical practice in dyslipidemia treatment.Trial Registration: ChiCTR-IOR-15006496 . Registered on 29 May 2015.Protocol Version: WXJ.YRJN-HBT-V1.0 (21 Jan 2015). [ABSTRACT FROM AUTHOR]

This paper presents an analytical solution for electrothermoelastic behavior of FGPM (functionally graded piezoelectric material) cylindrical shell. The cylindrical shell is assumed to be made up of two piezoelectric materials with their volume fractures varying along the thickness according to a simple power law. Based on classical thin shell theory, an analytical solution for electrothermoelastic performance of the FGPM cylindrical shell is presented. To investigate the influence of the power lower exponent, thermal environment, mechanical loading and electric boundary conditions on the electrothermoelastic behavior of FGPM cylindrical shells, numerical examples are presented and discussed, and some meaningful and valuable results are discovered, which will be very helpful for the design and application of such smart sensory structures. [ABSTRACT FROM AUTHOR]

A methanol microsensor integrated with a micro heater manufactured using the complementary metal oxide semiconductor (CMOS)-microelectromechanical system (MEMS) technique was presented. The sensor has a capability of detecting low concentration methanol gas. Structure of the sensor is composed of interdigitated electrodes, a sensitive film and a heater. The heater located under the interdigitated electrodes is utilized to provide a working temperature to the sensitive film. The sensitive film prepared by the sol-gel method is tin dioxide doped cadmium sulfide, which is deposited on the interdigitated electrodes. To obtain the suspended structure and deposit the sensitive film, the sensor needs a post-CMOS process to etch the sacrificial silicon dioxide layer and silicon substrate. The methanol senor is a resistive type. A readout circuit converts the resistance variation of the sensor into the output voltage. The experimental results show that the methanol sensor has a sensitivity of 0.18 V/ppm. [ABSTRACT FROM AUTHOR]

Future galaxy surveys will measure baryon acoustic oscillations (BAOs) with high significance and a complete understanding of the anisotropies of BAOs in redshift space will be important to exploit the cosmological information in BAOs. Here we describe the anisotropies that arise in the redshift-space galaxy two-point correlation function (2PCF) and elucidate the origin of features that arise in the dependence of BAOs on the angle between the orientation of the galaxy pair and the line of sight. We do so with a derivation of the configuration-space 2PCF using the streaming model. We find that, contrary to common belief, the locations of BAO peaks in the redshift-space 2PCF are anisotropic even in linear theory. Anisotropies in BAO depend strongly on the method of extracting the peak, showing a maximum of 3 per cent angular variation. We also find that extracting the BAO peak of the radius-square-weighted 2PCF, r²ξ(r, μ), where μ is the cosine between the line of sight and separation, reduces the anisotropy significantly to sub-per-cent level angular variations. When subtracting the tilt due to the broad-band behaviour of the 2PCF, the BAO bump is enhanced along the line of sight because of local infall velocities towards the BAO bump. Moving beyond the BAOs, precise measurement of the angular dependence of the redshift-space 2PCF on large scales, where linear theory models the anisotropies accurately, will allow new geometrical tests of dark energy. [ABSTRACT FROM AUTHOR]

We study the size distribution of spontaneous knots on semiflexible chains confined in square cross-section channels using Monte Carlo simulations. The most probable knot size, i.e. the metastable knot size, is found to vary nonmonotonically with the channel size. In the case of weak confinement, the metastable knot size is larger than the knot size in bulk because the segments within the knot feel less channel confinement than the segments outside the knot, and the channel pushes the segments into knot cores to reduce the overall free energy. Conversely, in the case of strong confinement, the metastable knot size is smaller than the one in bulk because the segments within the knot experience more channel confinement, and the channel expels segments from the knot core. We demonstrate that a simple theory can capture this nonmonotonic behavior and quantitatively explain the metastable knot size as a function of the channel size. These results may have implications for tuning the channel size to either generate or screen knots. [ABSTRACT FROM AUTHOR]

Recent theoretical progress has explained the physics of knotting of semiflexible polymers, yet knotting of flexible polymers is relatively unexplored. We herein develop a new theory for the size distribution of knots on a flexible polymer and the existence of metastable knots. We show the free energy of a flexible molecule in a tube can be mapped to quantitatively reproduce the free energy distribution of a knot on a flexible chain. The size distribution of knots on flexible chains is expected to be universal and might be observed at a macroscopic scale, such as a string of hard balls. [ABSTRACT FROM AUTHOR]

Recent angle-resolved photoemission reveals that the doping level in some BiS2-based superconductors is much lower than the nominal one. Here we determine the pairing function at such a realistic low doping level by a functional renormalization group (ERG) and study the resulting physical properties by an FRG-based effective mean field theory. We find that the pairing is a mixture of singlets and triplets due to spin-orbital coupling, and the triplet components dominate. The gap function transforms as a d*x2-y2-wave under simultaneous rotation of spin and lattice, but is nodeless on the Fermi pockets which avoid the nodal lines. The specific heat, superfluid density, and Knight shift are similar to that in a fully gapped conventional 5-wave superconductor, in agreement with available experiments. However, the absence of the Hebel-Slichter peak in spin-lattice relaxation rate (in the dirty limit), the impurity induced in-gap states, and the gapless edge states (due to the weak topological nature of the pairing) are defining properties of the nodeless d*x2-y2-wave pairing to be measured in future experiments. [ABSTRACT FROM AUTHOR]

: The design and fabrication of an ethanol microsensor integrated with a readout circuit on-a-chip using the complementary metal oxide semiconductor (CMOS)-microelectro -mechanical system (MEMS) technique are investigated. The ethanol sensor is made up of a heater, a sensitive film and interdigitated electrodes. The sensitive film is tin dioxide that is prepared by the sol-gel method. The heater is located under the interdigitated electrodes, and the sensitive film is coated on the interdigitated electrodes. The sensitive film needs a working temperature of 220 °C. The heater is employed to provide the working temperature of sensitive film. The sensor generates a change in capacitance when the sensitive film senses ethanol gas. A readout circuit is used to convert the capacitance variation of the sensor into the output frequency. Experiments show that the sensitivity of the ethanol sensor is 0.9 MHz/ppm. [ABSTRACT FROM AUTHOR]

The study develops an integrated humidity microsensor fabricated using the commercial 0.18 μm complementary metal oxide semiconductor (CMOS) process. The integrated humidity sensor consists of a humidity sensor and a ring oscillator circuit on-a-chip. The humidity sensor is composed of a sensitive film and branch interdigitated electrodes. The sensitive film is zinc oxide prepared by sol-gel method. After completion of the CMOS process, the sensor requires a post-process to remove the sacrificial oxide layer and to coat the zinc oxide film on the interdigitated electrodes. The capacitance of the sensor changes when the sensitive film adsorbs water vapor. The circuit is used to convert the capacitance of the humidity sensor into the oscillation frequency output. Experimental results show that the output frequency of the sensor changes from 84.3 to 73.4 MHz at 30 °C as the humidity increases 40 to 90 %RH. [ABSTRACT FROM AUTHOR]

Knotted structures can spontaneouslyoccur in polymers such asDNA and proteins, and the formation of knots affects biological functions,mechanical strength and rheological properties. In this work, we calculatethe equilibrium size distribution of trefoil knots in linear DNA usingoff-lattice simulations. We observe metastable knots on DNA, as predictedby Grosberg and Rabin. Furthermore, we extend their theory to incorporatethe finite width of chains and show an agreement between our simulationsand the modified theory for real chains. Our results suggest localizedknots spontaneously occur in long DNA and the contour length in theknot ranges from 600 to 1800 nm. [ABSTRACT FROM AUTHOR]

Evidence from the BICEP2 experiment for a significant gravitational-wave background has focused attention on inflaton potentials V(ϕ)∝ϕα with α=2 ("chaotic" or "m²ϕ²" inflation) or with smaller values of α, as may arise in axion-monodromy models. Here we show that reheating considerations may provide additional constraints to these models. The reheating phase preceding the radiation era is modeled by an effective equation-of-state parameter wre. The canonical reheating scenario is then described by wre=0. The simplest α=2 models are consistent with wre=0 for values of ns well within the current 1σ range. Models with α=1 or α=2/3 require a more exotic reheating phase, with −1/31/3, unless ns is close to the lower limit of the 2σ range. For m²ϕ² inflation and canonical reheating as a benchmark, we derive a relation log10(Tre/106 GeV)≃2000(ns-0.96) between the reheat temperature Tre and the scalar spectral index ns. Thus, if ns is close to its central value, then Tre≲106 GeV, just above the electroweak scale. If the reheat temperature is higher, as many theorists may prefer, then the scalar spectral index should be closer to ns≃0.965 (at the pivot scale k=0.05 Mpc-1), near the upper limit of the 1σ error range. Improved precision in the measurement of ns should allow m²ϕ², axion monodromy, and ϕ4 models to be distinguished, even without precise measurement of r, and to test the m²ϕ² expectation of ns≃0.965. [ABSTRACT FROM AUTHOR]

This study investigates the fabrication and characterization of an acetone microsensor with a ring oscillator circuit using the commercial 0.18 μm complementary metal oxide semiconductor (CMOS) process. The acetone microsensor contains a sensitive material, interdigitated electrodes and a polysilicon heater. The sensitive material is α-Fe2O3 synthesized by the hydrothermal method. The sensor requires a post-process to remove the sacrificial oxide layer between the interdigitated electrodes and to coat the α-Fe2O3 on the electrodes. When the sensitive material adsorbs acetone vapor, the sensor produces a change in capacitance. The ring oscillator circuit converts the capacitance of the sensor into the oscillation frequency output. The experimental results show that the output frequency of the acetone sensor changes from 128 to 100 MHz as the acetone concentration increases 1 to 70 ppm. [ABSTRACT FROM AUTHOR]

Scaling regimes for polymers confinedto tubular channels are well established when the channel cross-sectionaldimension is either very small (Odjik regime) or large (classic deGennes regime) relative to the polymer Kuhn length. However, experimentsof confined polymers using DNA as a model system are usually locatedin the intermediate region between these two regimes. In the literature,controversy exists regarding the existence of the extended de Gennesregime in this intermediate region. Here we use simulations and theoryto reconcile conflicting theories and confirm the existence of extendedde Gennes regime. We show that prior work did not support the notionof this regime because of the use of a wrong confinement free energy.In a broad sense, the extended de Gennes regime corresponds to thesituation when excluded volume interaction is weaker than thermalenergy. Such a situation also occurs in many other cases, such assemidilute polymer solutions and polymers under tension. This workshould benefit the practical applications of nanochannels to stretchDNA, such as deepening the understanding of the relationship betweenthe chain extension and channel size and providing the scaling behaviorsof recoiling force for DNA at the entrance of nanochannels. [ABSTRACT FROM AUTHOR]

A humidity microsensor integrated with a readout circuit on-a-chip fabricated using the commercial 0.18 µm CMOS (complementary metal oxide semiconductor) process was presented. The integrated sensor chip consists of a humidity sensor and a readout circuit. The humidity sensor is composed of a sensitive film and interdigitated electrodes. The sensitive film is titanium dioxide prepared by the sol-gel method. The titanium dioxide is coated on the interdigitated electrodes. The humidity sensor requires a post-process to remove the sacrificial layer and to coat the titanium dioxide. The resistance of the sensor changes as the sensitive film absorbs or desorbs vapor. The readout circuit is employed to convert the resistance variation of the sensor into the output voltage. The experimental results show that the integrated humidity sensor has a sensitivity of 4.5 mV/RH% (relative humidity) at room temperature. [ABSTRACT FROM AUTHOR]

When a cosmic microwave background (CMB) photon travels from the surface of last scatter through spacetime metric perturbations, the polarization vector may rotate about its direction of propagation. This gravitational rotation is distinct from, and occurs in addition to, the lensing deflection of the photon trajectory. This rotation can be sourced by linear vector or tensor metric perturbations and is fully coherent with the curl deflection field. Therefore, lensing corrections to the CMB polarization power spectra as well as the temperature-polarization cross correlations due to nonscalar perturbations are modified. The rotation does not affect lensing by linear scalar perturbations, but needs to be included when calculations go to higher orders. We present complete results for weak lensing of the full-sky CMB power spectra by general linear metric perturbations, taking into account both deflection of the photon trajectory and rotation of the polarization. For the case of lensing by gravitational waves, we show that the B modes induced by the rotation largely cancel those induced by the curl component of deflection. [ABSTRACT FROM AUTHOR]

The fabrication and characterization of a radio frequency (RF) micromachined switch with annealing were presented. The structure of the RF switch consists of a membrane, coplanar waveguide (CPW) lines, and eight springs. The RF switch is manufactured using the complementary metal oxide semiconductor (CMOS) process. The switch requires a post-process to release the membrane and springs. The post-process uses a wet etching to remove the sacrificial silicon dioxide layer, and to obtain the suspended structures of the switch. In order to improve the residual stress of the switch, an annealing process is applied to the switch, and the membrane obtains an excellent flatness. The finite element method (FEM) software CoventorWare is utilized to simulate the stress and displacement of the RF switch. Experimental results show that the RF switch has an insertion loss of 0.9 dB at 35 GHz and an isolation of 21 dB at 39 GHz. The actuation voltage of the switch is 14 V. [ABSTRACT FROM AUTHOR]

This study investigates the design and fabrication of magnetic microsensors using the commercial 0.35 μm complementary metal oxide semiconductor (CMOS) process. The magnetic sensor is composed of springs and interdigitated electrodes, and it is actuated by the Lorentz force. The finite element method (FEM) software CoventorWare is adopted to simulate the displacement and capacitance of the magnetic sensor. A post-CMOS process is utilized to release the suspended structure. The post-process uses an anisotropic dry etching to etch the silicon dioxide layer and an isotropic dry etching to remove the silicon substrate. When a magnetic field is applied to the magnetic sensor, it generates a change in capacitance. A sensing circuit is employed to convert the capacitance variation of the sensor into the output voltage. The experimental results show that the output voltage of the magnetic microsensor varies from 0.05 to 1.94 V in the magnetic field range of 5-200 mT. [ABSTRACT FROM AUTHOR]

The study investigates the fabrication and characterization of an ethanol microsensor equipped with a heater. The ethanol sensor is manufactured using the commercial 0.18 µm complementary metal oxide semiconductor (CMOS) process. The sensor consists of a sensitive film, a heater and interdigitated electrodes. The sensitive film is zinc oxide prepared by the sol-gel method, and it is coated on the interdigitated electrodes. The heater is located under the interdigitated electrodes, and it is used to supply a working temperature to the sensitive film. The sensor needs a post-processing step to remove the sacrificial oxide layer, and to coat zinc oxide on the interdigitated electrodes. When the sensitive film senses ethanol gas, the resistance of the sensor generates a change. An inverting amplifier circuit is utilized to convert the resistance variation of the sensor into the output voltage. Experiments show that the sensitivity of the ethanol sensor is 0.35 mV/ppm. [ABSTRACT FROM AUTHOR]

Blob theory has been widely applied to describe polymer conformations and dynamics in nanoconfinement. In slit confinement, blob theory predicts a scaling exponent of 2/3 for polymer diffusivity as a function of slit height, yet a large body of experimental studies using DNA produce a scaling exponent significantly less than 2/3. In this work, we develop a theory that predicts that this discrepancy occurs because the segment correlation function for a semiflexible chain such as DNA does not follow the Flory exponent for length scales smaller than the persistence length. We show that these short length scale effects contribute significantly to the scaling for the DNA diffusivity, but do not appreciably affect the scalings for static properties. Our theory is fully supported by Monte Carlo simulations, quantitative agreement with DNA experiments, and the results reconcile this outstanding problem for confined polymers. [ABSTRACT FROM AUTHOR]

The study presents an ammonia microsensor integrated with a readout circuit on-a-chip fabricated using the commercial 0.18 μm complementary metal oxide semiconductor (CMOS) process. The integrated sensor chip consists of a heater, an ammonia sensor and a readout circuit. The ammonia sensor is constructed by a sensitive film and the interdigitated electrodes. The sensitive film is zirconium dioxide that is coated on the interdigitated electrodes. The heater is used to provide a working temperature to the sensitive film. A post-process is employed to remove the sacrificial layer and to coat zirconium dioxide on the sensor. When the sensitive film adsorbs or desorbs ammonia gas, the sensor produces a change in resistance. The readout circuit converts the resistance variation of the sensor into the output voltage. The experiments show that the integrated ammonia sensor has a sensitivity of 4.1 mV/ppm. [ABSTRACT FROM AUTHOR]

A zinc oxide nanorod ammonia microsensor integrated with a readout circuit on-a-chip fabricated using the commercial 0.35 µm complementary metal oxide semiconductor (CMOS) process was investigated. The structure of the ammonia sensor is composed of a sensitive film and polysilicon electrodes. The ammonia sensor requires a post-process to etch the sacrificial layer, and to coat the sensitive film on the polysilicon electrodes. The sensitive film that is prepared by a hydrothermal method is made of zinc oxide. The sensor resistance changes when the sensitive film adsorbs or desorbs ammonia gas. The readout circuit is used to convert the sensor resistance into the voltage output. Experiments show that the ammonia sensor has a sensitivity of about 1.5 mV/ppm at room temperature. [ABSTRACT FROM AUTHOR]

A high Q-factor (quality-factor) spiral inductor fabricated by the CMOS (complementary metal oxide semiconductor) process and a post-process was investigated. The spiral inductor is manufactured on a silicon substrate. A post-process is used to remove the underlying silicon substrate in order to reduce the substrate loss and to enhance the Q-factor of the inductor. The post-process adopts RIE (reactive ion etching) to etch the sacrificial oxide layer, and then TMAH (tetramethylammonium hydroxide) is employed to remove the silicon substrate for obtaining the suspended spiral inductor. The advantage of this post-processing method is its compatibility with the CMOS process. The performance of the spiral inductor is measured by an Agilent 8510C network analyzer and a Cascade probe station. Experimental results show that the Q-factor and inductance of the spiral inductor are 15 at 15 GHz and 1.8 nH at 1 GHz, respectively. [ABSTRACT FROM AUTHOR]

This study presents the fabrication and characterization of a humidity microsensor that consists of interdigitated electrodes and a sensitive film. The area of the humidity microsensor is about 2 mm2. The sensitive film is polyaniline doping polyvinyl alcohol (PVA) that is prepared by the sol-gel method, and the film has nanofiber and porous structures that help increase the sensing reaction. The commercial 0.35 μm Complimentary Metal Oxide Semiconductor (CMOS) process is used to fabricate the humidity microsensor. The sensor needs a post-CMOS process to etch the sacrificial layer and to coat the sensitive film on the interdigitated electrodes. The sensor produces a change in resistance as the polyaniline/PVA film absorbs or desorbs vapor. Experimental results show that the sensitivity of the humidity sensor is about 12.6 kΩ/%RH at 25 °C. [ABSTRACT FROM AUTHOR]

The study presents a micro carbon monoxide (CO) sensor integrated with a readout circuit-on-a-chip manufactured by the commercial 0.35 μm complementary metal oxide semiconductor (CMOS) process and a post-process. The sensing film of the sensor is a composite cobalt oxide nanosheet and carbon nanotube (CoOOH/CNT) film that is prepared by a precipitation-oxidation method. The structure of the CO sensor is composed of a polysilicon resistor and a sensing film. The sensor, which is of a resistive type, changes its resistance when the sensing film adsorbs or desorbs CO gas. The readout circuit is used to convert the sensor resistance into the voltage output. The post-processing of the sensor includes etching the sacrificial layers and coating the sensing film. The advantages of the sensor include room temperature operation, short response/recovery times and easy post-processing. Experimental results show that the sensitivity of the CO sensor is about 0.19 mV/ppm, and the response and recovery times are 23 s and 34 s for 200 ppm CO, respectively. [ABSTRACT FROM AUTHOR]

The study investigates a capacitive micro pressure sensor integrated with a ring oscillator circuit on a chip. The integrated capacitive pressure sensor is fabricated using the commercial CMOS (complementary metal oxide semiconductor) process and a post-process. The ring oscillator is employed to convert the capacitance of the pressure sensor into the frequency output. The pressure sensor consists of 16 sensing cells in parallel. Each sensing cell contains a top electrode and a lower electrode, and the top electrode is a sandwich membrane. The pressure sensor needs a post-CMOS process to release the membranes after completion of the CMOS process. The post-process uses etchants to etch the sacrificial layers, and to release the membranes. The advantages of the post-process include easy execution and low cost. Experimental results reveal that the pressure sensor has a high sensitivity of 7 Hz/Pa in the pressure range of 0-300 kPa. [ABSTRACT FROM AUTHOR]

In this study, we fabricated a wireless micro FET (field effect transistor) pressure sensor based on the commercial CMOS (complementary metal oxide semiconductor) process and a post-process. The wireless micro pressure sensor is composed of a FET pressure sensor, an oscillator, an amplifier and an antenna. The oscillator is adopted to generate an ac signal, and the amplifier is used to amplify the sensing signal of the pressure sensor. The antenna is utilized to transmit the output voltage of the pressure sensor to a receiver. The pressure sensor is constructed by 16 sensing cells in parallel. Each sensing cell contains an MOS (metal oxide semiconductor) and a suspended membrane, which the gate of the MOS is the suspended membrane. The post-process employs etchants to etch the sacrificial layers in the pressure sensor for releasing the suspended membranes, and a LPCVD (low pressure chemical vapor deposition) parylene is adopted to seal the etch holes in the pressure. Experimental results show that the pressure sensor has a sensitivity of 0.08 mV/kPa in the pressure range of 0-500 kPa and a wireless transmission distance of 10 cm. [ABSTRACT FROM AUTHOR]

In this study we used the commercial 0.35 μm CMOS (complementary metal oxide semiconductor) process and simple maskless post-processing to fabricate an array of micromirrors exhibiting high natural frequency. The micromirrors were manufactured from aluminum; the sacrificial layer was silicon dioxide. Because we fabricated the micromirror arrays using the standard CMOS process, they have the potential to be integrated with circuitry on a chip. For post-processing we used an etchant to remove the sacrificial layer and thereby suspend the micromirrors. The micromirror array contained a circular membrane and four fixed beams set symmetrically around and below the circular mirror; these four fan-shaped electrodes controlled the tilting of the micromirror. A MEMS (microelectromechanical system) motion analysis system and a confocal 3D-surface topography were used to characterize the properties and configuration of the micromirror array. Each micromirror could be rotated in four independent directions. Experimentally, we found that the micromirror had a tilting angle of about 2.55° when applying a driving voltage of 40 V. The natural frequency of the micromirrors was 59.1 kHz. [ABSTRACT FROM AUTHOR]

This study presents the fabrication and characterization of a micromechanical tunable in-plane resonator. The resonator is manufactured using the commercial 0.35 μm complementary metal oxide semiconductor (CMOS) process. The resonator is made of aluminum, and the sacrificial layer is silicon dioxide. The post-process involves only one maskless etching step using an etchant to remove the sacrificial layer. The resonator includes three parts: a driving part to provide a driving force, a sensing part that is used to detect a change in capacitance when the resonator is vibrating, and a tuning part that changes the resonant frequency of the resonator. The main advantages of the tunable resonator are a low driving voltage and compatibility with the CMOS process. The resonant frequency of the resonator can be changed upon applying a dc voltage to the tuning part. To reduce the driving voltage, the driving part is designed as comb-finger rows. Experimental results show that the resonator has a resonant frequency of about 183 kHz and a driving voltage of 10 V; the resonant frequency increases 14 kHz when a tuning voltage of 30 V is applied. The resonator has a maximum frequency-tuning ratio of 7.6%. [ABSTRACT FROM AUTHOR]

This study presents the fabrication of a polyaniline nanofiber ammonia sensor integrated with a readout circuit on a chip using the commercial 0.35 μm complementary metal oxide semiconductor (CMOS) process and a post-process. The micro ammonia sensor consists of a sensing resistor and an ammonia sensing film. Polyaniline prepared by a chemical polymerization method was adopted as the ammonia sensing film. The fabrication of the ammonia sensor needs a post-process to etch the sacrificial layers and to expose the sensing resistor, and then the ammonia sensing film is coated on the sensing resistor. The ammonia sensor, which is of resistive type, changes its resistance when the sensing film adsorbs or desorbs ammonia gas. A readout circuit is employed to convert the resistance of the ammonia sensor into the voltage output. Experimental results show that the sensitivity of the ammonia sensor is about 0.88 mV/ppm at room temperature. [ABSTRACT FROM AUTHOR]

Abstract  Wireless mesh networks have attracted increasing attention and deployment as a high-performance and low-cost solution to last-mile broadband Internet access. Traffic routing plays a critical role in determining the performance of a wireless mesh network. To investigate the best routing solution, existing work proposes to formulate the mesh network routing problem as an optimization problem. In this problem formulation, traffic demand is usually implicitly assumed as static and known a priori. Contradictorily, recent studies of wireless network traces show that the traffic demand, even being aggregated at access points, is highly dynamic and hard to estimate. Thus, in order to apply the optimization-based routing solution into practice, one must take into account the dynamic and unpredictable nature of wireless traffic demand. This paper presents an integrated framework for wireless mesh network routing under dynamic traffic demand. This framework consists of two important components: traffic estimation and routing optimization. By studying the traces collected at wireless access points, we first present a traffic estimation method which predicts future traffic demand based on its historical data using time-series analysis. This method provides not only the mean value of the future traffic demand estimation but also its statistical distribution. We further investigate the optimal routing strategies for wireless mesh network which take these two forms of traffic demand estimations as inputs. The goal is to balance the traffic load so that minimum congestion will be incurred. This routing objective could be transformed into the throughput optimization problem where the throughput of aggregated flows is maximized subject to fairness constraints that are weighted by the traffic demands. Based on linear programming, we present two routing algorithms which consider the mean value and the statistical distribution of the predicted traffic demands, respectively. The trace-driven simulation study demonstrates that our integrated traffic estimation and routing optimization framework can effectively incorporate the traffic dynamics in mesh network routing. [ABSTRACT FROM AUTHOR]

A nonoverlapping domain decomposition iterative procedure is developed and analyzed for generalized Stokes problems and their finite element approximate problems in RN(N=2,3). The method is based on a mixed-type consistency condition with two parameters as a transmission condition together with a derivative-free transmission data updating technique on the artificial interfaces. The method can be applied to a general multi-subdomain decomposition and implemented on parallel machines with local simple communications naturally. [ABSTRACT FROM AUTHOR]

The problem of axisymmetric nonlinear vibration for shallow thin spherical and conical shells when temperature and strain fields are coupled is studied. Based on the large deflection theories of von Kármán and the theory of thermoelasticity, the whole governing equations and their simplified type are derived. The time-spatial variables are separated by Galerkin’s technique, thus reducing the governing equations to a system of time-dependent nonlinear ordinary differential equation. By means of regular perturbation method and multiple-scales method, the first-order approximate analytical solution for characteristic relation of frequency vs amplitude parameters along with the decay rate of amplitude are obtained, and the effects of different geometric parameters and coupling factors as well as boundary conditions on thermoelastically coupled nonlinear vibration behaviors are discussed. [ABSTRACT FROM AUTHOR]

Provides a framework for modeling the phase noise in complementary metial-oxide-semiconductor (CMOS) ring oscillators. Analyzes both linear and nonlinear operations; Illustrates how fast rail-to-rail switching is required to achieve low phase noise.