Bi-polar

Bipolar plates, a critical component of proton exchange membrane fuel cell (PEMFC), are constructed out of alloys of Ti, Pt, Cr, or graphitic materials that have limitations. Electrical conductivity, cost, and corrosion resistance are among the critical considerations for bi-polar plate material. Graphene, which possesses impressive conductivity and toughness, is an attractive option as coating on metallic substrates of PEMFC bipolar plates. This study investigates corrosion resistance and its durability due to graphene developed by chemical vapor deposition on a pure Ni-Cu alloy and a commercial Ni-Cu alloy in 0...

Generating the structure of the hydrophobic core is based on the orientation of hydrophobic residues towards the central part of the protein molecule with the simultaneous exposure of polar residues. Such a course of the protein folding process takes place with the active participation of the polar water environment. While the self-assembly process leading to the formation of micelles concerns freely moving bi-polar molecules, bipolar amino acids in polypeptide chain have limited mobility due to the covalent bonds...

PURPOSE: To improve the temperature monitoring precision using multi-echo proton resonance frequency shift-based thermometry with view-sharing acceleration for MR-guided laser interstitial thermal therapy (MRgLITT) on a 0.5T low-field MR system. METHODS: Both precision and speed of the temperature measurement for clinical MRgLITT treatments suffer at low-field, due to reduced image signal-to-noise ratio (SNR), decreased temperature-induced phase changes, and limited RF receiver channels...

Recycling waste brine from the Kimchi production process is an important environmental and industry issue. We applied an underwater plasma to reduce food-borne pathogens in the waste brine. The capillary electrodes supplied by alternating current (AC) bi-polar pulsed power were applied to treat 100 L of waste brine. The inactivation efficacy was analyzed using four different agars (Tryptic Soy Agar (TSA), Marine agar (MA), de Man Rogosa Sharpe Agar (MRS), and Yeast Extract-Peptone-Dextrose (YPD), respectively...

Organic electrode materials are promising for the future energy storage systems owing to their tunable structures, abundant resources and environmental friendliness etc. Many advanced lithium-ion batteries (LIBs) with organic electrodes are developed and show excellent performance. However, developing organic materials with overall superior performance still face great challenges such as low capacity, poor stability, inferior conductivity and low utilization of active sites. To address these issues, a bi-polar polymer (Fc-DAB) is designed and further polymerized in-situ with three-dimensional graphene (3DG), offering a hybrid material (Fc-DAB@3DG) with a variety of merits...

We present the design process and implementation of fully open-source, ultra-low noise programmable current source systems in two configurations. Although originally designed as coil drivers for Optically Pumped Magnetometers (OPMs), the device specifications make them potentially useful in a range of applications. The devices feature a bi-directional current range of ±10 and ±250 mA on three independent channels with 16-bit resolution. Both devices feature a narrow 1/f noise bandwidth of 1 Hz, enabling magnetic field manipulation for high-performance OPMs...

Infection caused by extracellular single-celled trypanosomes triggers a lethal chronic wasting disease in livestock and game animals. Through screening of 10 Trypanosoma evansi field isolates, exhibiting different levels of virulence in mice, the current study identifies an experimental disease model in which infection can last well over 100 days, mimicking the major features of chronic animal trypanosomosis. In this model, despite the well-controlled parasitemia, infection is hallmarked by severe trypanosomosis-associated pathology...

OBJECTIVE: The purpose of this study was to investigate alpha power as an objective measure of effortful listening in continuous speech with scalp and ear-EEG. METHODS: Scalp and ear-EEG were recorded simultaneously during presentation of a 33-s news clip in the presence of 16-talker babble noise. Four different signal-to-noise ratios (SNRs) were used to manipulate task demand. The effects of changes in SNR were investigated on alpha event-related synchronization (ERS) and desynchronization (ERD)...

INTRODUCTION: Post-adenotonsillectomy pain is often severe, requiring substantial analgesia in the first 48-72 h. This pain is not only distressing to the patient and his or her parents, but often reflects poorly on an otherwise well performed procedure. Safe, simple and effective post-adenotonsillectomy pain control is still clinically elusive, even though a multitude of surgical and analgesic interventions have been proposed. OBJECTIVES: To investigate the analgesic properties of immediate post-operative application of xylocaine 10% pump spray to the tonsillar fossae in children having undergone adenotonsillectomy and how this impacts on anesthetic emergence and pain control in the first 24-h...

A huge number of bacterial species are motile by flagella, which allow them to actively move toward favorable environments and away from hazardous areas and to conquer new habitats. The general perception of flagellum-mediated movement and chemotaxis is dominated by the Escherichia coli paradigm, with its peritrichous flagellation and its famous run-and-tumble navigation pattern, which has shaped the view on how bacteria swim and navigate in chemical gradients. However, a significant amount-more likely the majority-of bacterial species exhibit a (bi)polar flagellar localization pattern instead of lateral flagella...

BACKGROUND: The efficacy of bipolar ionisation in the healthcare setting has yet to be proven. A major limitation of studies sponsored by industry has been assessment of efficiency within test chambers in which ozone levels are not adequately controlled. AIM: The objective of this study was to assess the effectiveness of bipolar ionisation against antimicrobial-resistant bacteria as well as fungi and human coronavirus within a controlled testing chamber designed to mitigate the effect of ozone...

Online sexual activities (OSA) refer to Internet-based activities, behaviours, and materials that are sexual in nature. Many young adults engage in OSA, but report doing so infrequently. Most OSA outcome research has focused on negative effects of only some types of OSA (e.g., viewing pornography online). The goal of this study was to enhance knowledge on the range of OSA outcomes by qualitatively exploring young adults' self-reported negative and positive outcomes from OSA experiences generally. University/College students from Canada ( n = 246), Germany ( n = 411), Sweden ( n = 299), and the USA ( n = 123) completed an online survey that included open-ended questions about "one of the most positive/negative effects that engaging in online sexual activities has had on your life"...

Background Bi-polar electrical cortical stimulation during awake craniotomy has been the gold standard for mapping eloquent cortex to preserve speech. Unfortunately, not all patients can tolerate awake surgery. Monopolar hi-frequency electrical stimulation can be conducted while a patient is under general anesthesia. Utilizing this technique and targeting the orofacial muscles as surrogates for motor speech may provide a limited alternative to awake cortical mapping in patients unable to undergo surgery awake...

Diaphanous (DIAPH) three (DIAPH3) is a member of the formin proteins that have the capacity to nucleate and elongate actin filaments and, therefore, to remodel the cytoskeleton. DIAPH3 is essential for cytokinesis as its dysfunction impairs the contractile ring and produces multinucleated cells. Here, we report that DIAPH3 localizes at the centrosome during mitosis and regulates the assembly and bipolarity of the mitotic spindle. DIAPH3-deficient cells display disorganized cytoskeleton and multipolar spindles...

Failure of the cell to properly regulate the number and intracellular positioning of their flagella, has detrimental effects on the cells' swimming ability. The flagellation pattern of numerous bacteria is regulated by the NTPases FlhF and FlhG. In general, FlhG controls the number of flagella produced, whereas FlhF coordinates the position of the flagella. In the human pathogen Vibrio parahaemolyticus , its single flagellum is positioned and formed at the old cell pole. Here, we describe the spatiotemporal localization of FlhF and FlhG in V...

Antarctic ice mass balance is determined by precipitation and ice discharge, and understanding their relative contributions to contemporary Antarctic ice mass change is important to project future ice mass loss and resulting sea level rise. There has been evidence that anomalous precipitation affects Antarctic ice mass loss estimates, and thus the precipitation contribution should be understood and considered in future projections. In this study, we revisit changes in Antarctic ice mass over recent decades and examine precipitation contributions over this period...

Research on the protein folding problem differentiates the protein folding process with respect to the duration of this process. The current structure encoded in sequence dogma seems to be clearly justified, especially in the case of proteins referred to as fast-folding, ultra-fast-folding or downhill. In the present work, an attempt to determine the characteristics of this group of proteins using fuzzy oil drop model is undertaken. According to the fuzzy oil drop model, a protein is a specific micelle composed of bi-polar molecules such as amino acids...

BACKGROUND: The stroma of odontogenic cysts/tumors may confer them differential biological behavior. We aimed to investigate the immuno-expression of stem cell markers (Nanog, SOX2, Oct4, CD34) in the stroma of odontogenic cysts and tumors. CD34 was investigated exclusively as a marker for stromal fibroblast/fibrocyte cells (CD34+SFCs). CD34+SFCs were also investigated ultrastructurally. METHODS: Ten cases each of primary odontogenic keratocyst (OKC), recurrent OKC, dentigerous cyst, ameloblastoma, unicystic ameloblastoma, odontogenic myxoma and 7 syndromic OKC were included...

A 65-year-old woman was referred for catheter ablation in the treatment of persistent tachycardia after surgery for atrial fibrillation and mitral regurgitation. Bipolar voltage mapping of both atria revealed that severe and extensive atrial fibrosis isolated the sinoatrial node from the atrioventricular junction and led to the coexistence of sinus bradycardia and persistent junctional tachycardia.

We investigate the phenomena of political bi-polarization in a population of interacting agents by means of a generalized version of the model introduced by Vazquez et al. [Phys. Rev. E 101, 012101 (2020)] for the dynamics of voting intention. Each agent has a propensity p in [0,1] to vote for one of two political candidates. In an iteration step, two randomly chosen agents i and j with respective propensities pi and pj interact, and then pi either increases by an amount h>0 with a probability that is a nonlinear function of pi and pj or decreases by h with the complementary probability...