Direct Bias Research Articles

Investigations of axioms of twist grain boundary phases (TGBPs) in binary mixture of liquid crystals

In this paper, the investigated mixture of liquid crystals shows a spacious range of twist grain boundary phases (TGBPs). Thermo dynamical, optical and dielectric measurements confirmed the presence of TGBPs in the mixtures of nematic and cholesteric liquid crystals. In the heating cycle, differential scanning calorimetry (DSC) thermogram shows the mixed different TGBPs at the high scanning rate. Cylindrical and cone-like textures with brushes of TGBA* is observed under the optical investigation. The grain boundaries and blocks of smectic phases are twisting two times around an axis. Wide-ranging dielectric investigation of nematic and cholesteric liquid crystal mixture have been performed in the 50 Hz–10 MHz range of frequency for the homogeneous conditions. In the absence of direct bias, TGBA* phase exhibits two dielectric relaxation processes, soft mode (SM) and process in the grain boundaries (PGBs). In the presence of electric field, grain boundaries steadily demolished the phases. Whereas the weak dielectric relaxation processes have been distinguished in the presence of the electric field in the TGBPs.

Comparative effectiveness of different acupuncture courses in functional constipation: A Bayesian network meta-analysis of clinical trials

AimThe purpose of this study was to examine the comparative effectiveness of different acupuncture courses for functional constipation (FC). BackgroundThere is a need to optimize the treatment course of acupuncture for FC to improve efficacy and save health resources. MethodsWe performed a systematic electronic search of eight databases from inception to April 2021. Randomized controlled trials comparing acupuncture treatment with sham acupuncture were included. The main outcome indicators were complete spontaneous bowel movement (CSBM), spontaneous bowel movement, Bristol Stool Form Scale (BSFS), responder rate and safety evaluation (SE). ResultsIn this network meta-analysis, 19 studies with 1753 participants and 8 different acupuncture treatments were included. Using the consistency model via Monte Carlo simulation iterations, we found that the effect of acupuncture treatment at 3/4 weeks may be better in terms of CSBM and BSFS. The results of rank probability analysis showed that 6 weeks of treatment may be better for the responder rate, and 2 weeks of treatment may be better for SE. And, subgroup analysis found that, for patients with chronic severe functional constipation (CSFC), 8 weeks of acupuncture treatment may be the best for CSBM. ConclusionsBy indirect comparison, 3/4 weeks of acupuncture treatment may be the optimal course of treatment for FC in terms of improving bowel frequency and stool shape. And for CSFC, 8 weeks of acupuncture treatment may be the best. However, there is still a lack of direct comparison and publication bias that affects the accuracy of research results.

Genomic Legacies of Ancient Adaptation Illuminate GC-Content Evolution in Bacteria.

Bacterial evolution is characterized by strong purifying selection as well as rapid adaptive evolution in changing environments. In this context, the genomic GC content (genomic GC) varies greatly but presents some level of phylogenetic stability, making it challenging to explain based on current hypotheses. To illuminate the evolutionary mechanisms of the genomic GC, we analyzed the base composition and functional inventory of 11,083 representative genomes. A phylogenetically constrained bimodal distribution of the genomic GC, which mainly originated from parallel divergences in the early evolution, was demonstrated. Such variation of the genomic GC can be well explained by DNA replication and repair (DRR), in which multiple pathways correlate with the genomic GC. Furthermore, the biased conservation of various stress-related genes, especially the DRR-related ones, implies distinct adaptive processes in the ancestral lineages of high- or low-GC clades which are likely induced by major environmental changes. Our findings support that the mutational biases resulting from these legacies of ancient adaptation have changed the course of adaptive evolution and generated great variation in the genomic GC. This highlights the importance of indirect effects of natural selection, which indicates a new model for bacterial evolution. IMPORTANCE GC content has been shown to be an important factor in microbial ecology and evolution, and the genomic GC of bacteria can be characterized by great intergenomic heterogeneity, high intragenomic homogeneity, and strong phylogenetic inertia, as well as being associated with the environment. Current hypotheses concerning direct selection or mutational biases cannot well explain these features simultaneously. Our findings of the genomic GC showing that ancient adaptations have transformed the DRR system and that the resulting mutational biases further contributed to a bimodal distribution of it offer a more reasonable scenario for the mechanism. This would imply that, when thinking about the evolution of life, diverse processes of adaptation exist, and combined effects of natural selection should be considered.

The role of attention in decision-making under risk in gambling disorder: An eye-tracking study

Gambling disorder (GD) is a behavioural addiction characterized by impairments in decision-making, favouring risk- and reward-prone choices. One explanatory factor for this behaviour is a deviation in attentional processes, as increasing evidence indicates that GD patients show an attentional bias toward gambling stimuli. However, previous attentional studies have not directly investigated attention during risky decision-making. 26 patients with GD and 29 healthy matched controls (HC) completed a mixed gambles task combined with eye-tracking to investigate attentional biases for potential gains versus losses during decision-making under risk. Results indicate that compared to HC, GD patients gambled more and were less loss averse. GD patients did not show a direct attentional bias towards gains (or relative to losses). Using a recent (neuro)economics model that considers average attention and trial-wise deviations in average attention, we conducted fine-grained exploratory analyses of the attentional data. Results indicate that the average attention for gains in GD patients moderated the effect of gain value on gambling choices, whereas this was not the case for HC. GD patients with high average attention for gains started gambling at less high gain values. A similar trend-level effect was found for losses, where GD patients with high average attention for losses stopped gambling at lower loss values. This study gives more insight into how attentional processes in GD play a role in gambling behaviour, which could have implications for the development of future treatments focusing on attentional training or for the development of interventions that increase the salience of losses.

Enhanced Gas Detection by Altering Gate Voltage Polarity of Polypyrrole/Graphene Field-Effect Transistor Sensor

This work introduces a new measurement methodology for enhancing gas detection by tuning the magnitude and polarity of back-gate voltage of a field-effect transistor (FET)-based sensor. The aim is to simultaneously strengthen the sensor response and accelerate the sensor recovery. In addition, this methodology can consume less energy compared with conventional measurements by direct current bias. To illustrate the benefits of the proposed methodology, we fabricated and characterized a polypyrrole/graphene (PPy/G) FET sensor for ammonia (NH3) detection. Our experiment, simulation and calculation results demonstrated that the redox reaction between the NH3 molecules and the PPy/G sensitive layer could be controlled by altering the polarity and the magnitude of the back-gate voltage. This proof-of-principle measurement methodology, which solves the inherent contradiction between high response and slow recovery of the chemiresistive sensor, could be extended to detect other gases, so as to improve global gas measurement systems. It opens up a new route for FET-based gas sensors in practical applications.

Research and analysis on suppression and influence of transformer direct current bias

DC bias generates a large DC component in the windings of the transformer in operation, thereby generating harmonics, causing vibration, noise, and overheating. In severe cases, it can cause damage to the transformer, which will affect the safe and stable operation of the AC system. This article takes the DC bias of the main transformer of a 220kV substation as an example, and uses the capacitance isolation method to suppress the DC bias. Due to the addition of capacitor equipment at the neutral point, the zero-sequence impedance of the main transformer and the change of the zero-sequence impedance of the power grid are changed, which has an impact on the zero-sequence (directional) current protection and ground distance protection. Through theoretical analysis and simulation research verification, for general 220kV substations, the capacitor DC isolation method (1.2Ω) can be used to suppress DC bias, which has a small impact on the relay protection and does not need to adjust the related protection settings.

Spray-Coated Superhydrophobic Overlayer with Photothermal and Electrothermal Functionalities for All-Weather De/anti-icing Applications.

High-performance de/anti-icing overlayers which can be deposited on diverse surfaces offer great potential in many industrial settings and daily life, yet a versatile overlayer applicable to all-weather conditions (high humidity, low temperature, raining, snowing, etc.) is in high demand for practical applications. This study presents the fabrication and application of a superhydrophobic overlayer with a bioinspired hierarchical surface which additionally possesses photothermal and electrothermal functionalities, so it can operate as a de/anti-icing layer in extreme environments. The overlayer, with a papilla-like microstructure similar to that of a lotus leaf, features polydopamine-decorated layered basic zinc acetate microparticles distributed in the framework of multiwalled carbon nanotubes. Specifically, the overlayer is superhydrophobic, and its capability of suppressing the condensation of water droplets and growth of ice crystals is verified by both in situ environmental scanning electron microscopy observations and freezing experiments. Moreover, the overlayer can be warmed up to 74 and 105 °C under the excitation of sunlight and direct current bias, respectively, which is sufficiently high for deicing in severe weather. It is worth mentioning that the overlayer is produced by a spray-coating technique; therefore, it is suitable for large-scale deployment on arbitrary substrate materials. The findings provide insights into a new strategy for engineering multifunctional overlayers and can lead to expanding applications of composite coatings.

Phase-space ab-initio direct and reverse ballistic-electron emission spectroscopy: Schottky barriers determination for Au/Ge(100)

We develop a phase-space ab-initio formalism to compute Ballistic Electron Emission Spectroscopy current–voltage I(V)’s in a metal–semiconductor interface. We consider injection of electrons into the conduction band for direct bias (V>0) and injection of holes into the valence band or injection of secondary Auger electrons into the conduction band for reverse bias (V<0). Here, an ab-initio description of the semiconductor inversion layer (spanning hundreds of Angstroms) is needed. Such formalism is helpful to get parameter-free best-fit values for the Schottky barrier, a key technological characteristic for metal–semiconductor rectifying interfaces. We have applied the theory to characterize the Au/Ge(001) interface; a double barrier is found for electrons injected into the conduction band – either directly or created by the Auger process – while only a single barrier has been identified for holes injected into the valence band.

What's Local about Local Television News?

Because capturing and analyzing local television news broadcasts is difficult, most research on campaign ocverage by local television stations centers on a single candidate race and a limited number of news broadcasts. This article expands existing research by examining all prime time election coverage by Philadelphia's four network affiliates in the final 30 days of the 2004 campagin. These stations virtually abandoned coverage of local and statewied races in favor of the presidential contest. Most coverage focused on campaign stategy rather than issues, but there is little evidence of direct bias favoring either Democrats or Republicans. Although stations generally ignored nonpresidential elections, they gave a fair amount of coverage to the mechanics of voting, which may provide voters with valuable locally based election information.

Single-modulator Based Multi-Format Switchable Signal Generator Without Background Noise

A photonic multi-format background-free binarily modulated microwave signal generator using a single dual-polarization dual-parallel Mach–Zehnder modulator is proposed and demonstrated. The proposed generator features good reconfiguration and switchability. By simply adjusting the direct current biases of the modulator, amplitude shift keying (ASK), phase shift keying (PSK) and frequency-shift keying (FSK) microwave signals can be generated. Benefiting from the complementary intensity modulation, there is no residual baseband modulated signal in the generated binarily modulated signals. The system does not involve any optical or electrical filters, which ensures good tunability of the generator. By changing the frequency of the driven microwave carrier and bit rate of the electrical coded signal, the frequency and rate of the generated multi-format signals can be adjusted accordingly. The multi-format switchable signal generator has great potential in multi-functional communication and radar systems.

Explaining women's political underrepresentation in democracies with high levels of corruption

AbstractMany democracies with high levels of corruption are also characterized by low levels of women's political representation. Do women candidates in democracies with high levels of corruption face overt voter discrimination? Do gender dynamics that are unique to highly corrupt, democratic contexts influence citizens’ willingness to vote for women? We answer these questions using two separate sets of experiments conducted in Ukraine: two vignette experiments and a conjoint analysis. In line with existing cross-sectional research on Ukraine, our experiments reveal little evidence of direct voter bias against women candidates. Our conjoint analysis also offers novel insights into the preferences of Ukrainian voters, showing that both men and women voters place a great deal of value in anti-corruption platforms, but voters are just as likely to support women and men candidates who say they will fight corruption. Our analysis suggests that women's political underrepresentation in highly corrupt contexts is driven more by barriers that prevent women from winning party nominations and running for office in the first place, rather than overt discrimination at the polls.

Acoustic wave amplification with thin film silicon bonded on lithium niobate

Signal processing with the use of acoustic waves is an important technology for various functions in radio frequency (RF) systems, including matched filtering in congested parts of the frequency spectrum. In order to generate long time delays on chip required for these applications, the acoustoelectric effect offers the ability to counter acoustic propagation losses while also generating inherent non-reciprocity. In this work, we demonstrate an approach to directly bond thin film silicon from 200 mm commercial silicon on insulator wafers on X-cut lithium niobate substrates with the use of plasma surface activation. The resulting delay line devices at 410 MHz demonstrate amplification of Rayleigh waves, with a peak non-reciprocal contrast between forward and reverse traveling waves of over 25 dB mm−1 under continuous direct current bias conditions. The demonstrated process can extend the functionality of traditionally passive piezoelectric RF microsystems.

A Method to Account for the Impact of Water Vapor on Observation‐Based Estimates of the Clear‐Sky Shortwave Direct Radiative Effect of Mineral Dust

AbstractThe shortwave direct radiative effect of dust, the difference between net shortwave radiative flux in a cloud free and cloud and aerosol free atmosphere, is typically estimated using forward calculations made with a radiative transfer model. However, estimates of the direct radiative effect made via this initial method can be highly uncertain due to difficultly in accurately describing the relevant optical and physical properties of dust used in these calculations. An alternative approach to estimate this effect is to determine the forcing efficiency, or the direct radiative effect normalized by aerosol optical depth. While this approach avoids the uncertainties associated with the initial method for calculating the direct effect, random errors and biases associated with this approach have not been thoroughly examined in literature. Here we explore biases in this observation‐based approach that are related to atmospheric water vapor. We use observations to show that over the Sahara Desert dust optical depth and column‐integrated atmospheric water vapor are positively correlated. We use three idealized radiative models of varying complexity to demonstrate that a positive correlation between dust and water vapor produces a positive bias in the dust forcing efficiency estimated via the observation‐based method. We describe a simple modification to the observation‐based method that correctly accounts for the correlation between dust and water vapor when estimating the forcing efficiency and use this method to estimate the instantaneous forcing efficiency of dust over the Sahara Desert using satellite data, obtaining −12.3 ± 6.68 to 20.9 ± 11.9 W m−2 per unit optical depth.

Fabrication of airbridges with gradient exposure

In superconducting quantum circuits, airbridges are critical for eliminating parasitic slotline modes of coplanar waveguide circuits and reducing crosstalks between direct current magnetic flux biases. Here, we present a technique for fabricating superconducting airbridges. With this technique, a single layer of photoresist is employed, and the gradient exposure process is used to define the profile of airbridges. In order to properly obtain the bridge profile, we design exposure dosage based on residual photoresist thickness and laser power calibrations. Compared with other airbridge fabrication techniques, the gradient exposure fabrication technique provides the ability to produce lossless superconducting airbridges with flexible size and, thus, is more suitable for large-scale superconducting quantum circuits. Furthermore, this method reduces the complexity of the fabrication process and provides a high fabrication yield.

Does concurrent self-administered transcranial direct current stimulation and attention bias modification training improve symptoms of binge eating disorder? Protocol for the TANDEM feasibility randomized controlled trial.

BackgroundBinge eating disorder (BED) is a common and disabling problem associated with impaired cognitive control. Preliminary studies show that brain-directed treatments, including transcranial direct current stimulation (tDCS) and attention bias modification training (ABMT), improve cognitive control and alleviate symptoms of BED. When combined, tDCS may enhance the effects of ABMT, and vice versa, thereby improving treatment outcomes.MethodsThis protocol describes a feasibility single-blind randomized sham-controlled trial of concurrent self-administered tDCS and ABMT in adults with BED (The TANDEM Trial). Eighty adults with BED will be randomly assigned to one of four groups: ABMT with real or sham self-administered tDCS, ABMT only, or waiting list control. In the treatment arms, participants will complete 10-sessions of their allocated intervention over 2–3 weeks. Outcomes will be assessed at baseline (T0), immediately post treatment (T1), and 6 weeks after end of treatment (T2), and at comparable timepoints for participants in the waitlist control group. Feasibility will be evaluated by assessing recruitment/retention rates and blinding success. Acceptability will be assessed quantitatively via participant ratings and qualitatively via semi-structured interviews. Episodes of binge eating at follow-up will be the primary clinical outcome and rate ratios from Poisson regression will be reported. Secondary outcomes will assess changes in ED and general psychopathology, attention bias toward high calorie foods, and executive function.DiscussionIt is hoped that data from the trial will contribute to the development of neurobiologically informed treatments for BED, provide insights into the potential use of at-home variants of tDCS, and inform the design of future large scale trials.

Effect of argon flow rate and direct current bias on the growth of boron nitride coating in low-temperature plasma

A microwave plasma chemical vapor deposition system was used to synthesize cubic boron nitride (cBN) coatings on diamond seeded silicon substrates using direct current (DC) bias. Effects of the argon (Ar) flow rate and bias voltage on the growth of the cBN coatings were investigated. Hydrogen (H2), argon (Ar), a mixture of diborane in H2 (95% H2, 5% B2H6), and N2 were used in the feed gas. A DC bias system was used for external biasing of the sample, which facilitates the goal of achieving sp3 bonded cBN. Fourier Transform Infrared Spectroscopy (FTIR) and X-ray Photoelectron Spectroscopy (XPS) revealed the existence of sp3-bonded BN in the produced samples. With increasing Ar flow, the cBN content in the coating increases and reaches a maximum at the maximum Ar flow of 400 SCCM used in this study. High-resolution XPS scans for B1s and N1s indicate that the deposited coating contains more than 70% cBN. This study demonstrates that energetic argon ions generated in a microwave-induced plasma significantly increase cBN content in the coating.

Effects of Electric Bias on Different Sc-Doped AlN-Based Film Bulk Acoustic Resonators

Film bulk acoustic resonators (FBARs) based on aluminum nitride (AlN) and scandium-doped aluminum nitride (AlScN) exhibit tremendous application aspects in the radio frequency front-end due to achievable high-frequency characteristics, superior thermal performances and compatibility with harsh environments. Delicately controlling the resonant frequency (fs) of FBAR is essential for integrating filters or modules. In this work, we provide a practical feasibility in adjusting fs of AlN and AlScN FBAR using external direct current electric bias (EDC). When applying a negative EDC (the direction along the reversed c-axis), fs shifts to a lower frequency, whereas a positive EDC brings a higher fs. In order to extract the equivalent values of the stiffness coefficient (c33), piezoelectric coefficient (e33) and dielectric constant (εzz) of AlN and AlScN piezoelectric materials, we adopted the electromechanical equivalent Mason model. The results show that the equivalent values of c33 increase with the change of EDC from negative to positive, and, on the other hand, those of e33 and εzz decrease. Our work provides a systematic investigation on the electric field-influenced stiffening effect of AlN and AlScN piezoelectric films and opens a feasibility for frequency-tunable resonators.

Investigation of transport properties of perovskite single crystals by pulsed and DC bias transient current technique

Time-of-flight (ToF) transient current method is an important technique to study the transport characteristics of semiconductors. Here, both the direct current (DC) and pulsed bias ToF transient current method are employed to investigate the transport properties and electric field distribution inside the MAPbI3 single crystal detector. Owing to the almost homogeneous electric field built inside the detector during pulsed bias ToF measurement, the free hole mobility can be directly calculated to be about 22 cm2⋅V−1⋅s−1, and the hole lifetime is around 6.5 μs–17.5 μs. Hence, the mobility-lifetime product can be derived to be 1.4 × 10−4 cm2⋅V−1–3.9 × 10−4 cm2⋅V−1. The transit time measured under the DC bias deviates with increasing voltage compared with that under the pulsed bias, which arises mainly from the inhomogeneous electric field distribution inside the perovskite. The positive space charge density can then be deduced to increase from 3.1 × 1010 cm−3 to 6.89 × 1010 cm−3 in a bias range of 50 V–150 V. The ToF measurement can provide us with a facile way to accurately measure the transport properties of the perovskite single crystals, and is also helpful in obtaining a rough picture of the internal electric field distribution.

Gender differences in peer review of innovation

AbstractResearch SummaryGender differences in peer review and the associated impact on innovation financing are well documented but less well understood. We study peer review in the National Aeronautics and Space Administration Small Business Innovation Research program, a public initiative seeking to increase women's access to innovation funds. We theorize that reviewers use status characteristics inappropriately as heuristics and create gender bias. Econometric analysis shows evidence of direct bias against female applicants, an effect linked to challenges for newcomers in demonstrating individual legitimacy rather than concerns about the organizational legitimacy of the associated firm. We also demonstrate a corrective redistribution to reverse this bias and create equity in the funding outcome. As these results negatively impact diversity in innovation, we propose policy recommendations to overcome this bias.Managerial SummaryPeer review is an important mechanism to rank and select technical proposals for funding. We examine the role of gender in a government program conducting this process. Controlling for the proposal quality and other factors, we show that the gender of the proposer is linked to lower scores. This effect is associated with proposals from females who are new to the program, suggesting their challenges in demonstrating credibility as leaders of these projects, and exacerbated by the fact that women represent a disproportionately high share of newcomers. Subsequently, the program reverses this bias such that the funding outcomes do not show the same inequities. This has important implications for policies supporting gender diversity in innovation.

BIAS GENDER DALAM NASKAH ADᾹB AL-MAR’ᾹH KARYA KH. MA’MUR NAWAWI (KAJIAN TEORI FEMINISME)

The issue of gender is still an interesting thing for literary researchers if it is associated with Islamic discourse, which will effectively influence various social, cultural, and even political changes. Problems that arise from a gender perspective focus on the social aspect that sees differences in human sexuality in their position in society. Likewise, one of the manuscripts, a cultural heritage, invites literary critics to analyze the critical study of the text of the Adābu Al-Mar'āh manuscript using the perspective of feminism theory. This research aims to analyze other gender-biased texts in the Adābu Al-Mar'āh manuscript. The research method used is the content analysis method with a qualitative approach or research that refers to the analysis of data linked to a problem to be investigated to produce a conclusion. In this manuscript, several text fragments are in the text that direct gender bias in the household environment. Gender biases in this text include; marginalization or restriction of the wife, gender stereotypes, and subordination or subordination of a wife. This is due to the view of inferiority toward a wife, including the wife who is considered a domestic role in the family, the wife only as a companion to the husband, and the wife who only has a role as a housewife.