Unit Charge Research Articles

Predicting Electrophoretic Mobility of Proteoforms for Large-Scale Top-Down Proteomics.

Large-scale top-down proteomics characterizes proteoforms in cells globally with high confidence and high throughput using reversed-phase liquid chromatography (RPLC)-tandem mass spectrometry (MS/MS) or capillary zone electrophoresis (CZE)-MS/MS. The false discovery rate (FDR) from the target-decoy database search is typically deployed to filter identified proteoforms to ensure high-confidence identifications (IDs). It has been demonstrated that the FDRs in top-down proteomics can be drastically underestimated. An alternative approach to the FDR can be useful for further evaluating the confidence of proteoform IDs after the database search. We argue that predicting retention/migration time of proteoforms from the RPLC/CZE separation accurately and comparing their predicted and experimental separation time could be a useful and practical approach. Based on our knowledge, there is still no report in the literature about predicting separation time of proteoforms using large top-down proteomics data sets. In this pilot study, for the first time, we evaluated various semiempirical models for predicting proteoforms' electrophoretic mobility (μef) using large-scale top-down proteomics data sets from CZE-MS/MS. We achieved a linear correlation between experimental and predicted μef of E. coli proteoforms (R2 = 0.98) with a simple semiempirical model, which utilizes the number of charges and molecular mass of each proteoform as the parameters. Our modeling data suggest that the complete unfolding of proteoforms during CZE separation benefits the prediction of their μef. Our results also indicate that N-terminal acetylation and phosphorylation both decrease the proteoforms' charge by roughly one charge unit.

Microphase Separation in Polyelectrolyte Blends: Weak Segregation Theory and Relation to Nuclear “Pasta”

We develop the weak segregation theory of microphase separation in stoichiometric blends of oppositely and weakly charged polyelectrolytes, which would be immiscible in the absence of charged units. Short-range repulsions between polycation and polyanion monomers induce the formation of oppositely charged domains, the size of which is controlled by their excess Coulomb energy. The diagram of blend morphologies is constructed in the framework of Leibler’s mean-field approach and to account for fluctuations within the Brazovskii–Fredrickson–Helfand approximation. Phase behavior of the polyelectrolyte blends is fully analogous to that of neutral diblock copolymers. The mean-field analysis predicts that the order–disorder transition (ODT) is second order for the symmetric blend. In asymmetric mixtures, an increasing incompatibility between polyelectrolytes triggers the usual cascade of first-order phase transitions, dis → bcc → hex → lam. Fluctuations alter the phase diagram topology and allow the direct transitions from the disordered state (dis) to hex and lam microphases; for the symmetric blend, ODT becomes weakly first order. We also discuss that both microphase separation in polyelectrolyte blends and the formation of nuclear “pasta” phases within neutron stars are governed by similar physical principles, despite the 6 orders of magnitude difference in the periods of these structures.

Abstract TP404: Optimizing Length of Stay Through an Integrated Communication Strategy

Background: At our comprehensive stroke center, the Stroke Unit bed ahead tool allows bed availability to be reported every four hours and identifies patients who may be available for discharge or transfer out of the unit. A Stroke Bed Ahead Algorithm is utilized and information is communicated using a paper format and an online text messaging system called EZ Texting. Purpose: The purpose of this study is to improve bed flow through coordination and facilitation of movement in the Stroke Unit and to provide quality control feedback of the efficiency of bed flow within the Stroke Unit. A bed ahead tool is utilized to decrease divert activity of the hospital and decrease length of stay on the Stroke Unit, thereby decreasing length of stay in the hospital. Intervention: The Stroke Unit charge and staff nurses evaluate patients appropriate for possible discharge or transfer out of the Stroke Unit. A Stroke Unit capacity text message is then sent out by the Charge Nurse or the Unit Coordinator every four hours starting at 0800. The capacity text message includes the total number of patients and patients pending to be received or transferred out of the unit. Results: Utilizing an integrated communication strategy decreased the length of stay of stroke population by 12%. Implications of Practice: Implementation of Stroke Unit capacity notification system decreases the length of stay and decreases divert activity of the hospital.

Design and Manufacturing of Thermoelectric Mini Portable Refrigerator using Autodesk Fusion 360 and Additive Manufacturing

The objective of this project is to develop portable thermoelectric refrigeration whose casing is designed using Autodesk Fusion 360 and manufactured by 3D printing. This refrigerator consists of thermoelectric module as cooling generator along with insulated cabin, thermostat and charging unit. Thermoelectric elements perform the same cooling function as Freon-based vapour compression or absorption refrigerators. The design of the refrigeration is based on the principle of thermoelectric module (i.e. Peltier effect) to create a hot side and a cold side. The cold side of the thermoelectric module is used for refrigeration purposes. On the other hand, the heat from the hot side of the module is rejected to the surroundings with the help of heat sinks and fan. Based on the heat load calculations, the thermoelectric module is selected. The system is fabricated and experimentally tested for the time taken to cool to the required temperature. The results showed that the system can maintain the temperature of approximately 10 °C with minimum power consumption of 64 Watt.

Design and Manufacturing of Thermoelectric Mini Portable Refrigerator using Autodesk Fusion 360 and Additive Manufacturing

The objective of this project is to develop portable thermoelectric refrigeration whose casing is designed using Autodesk Fusion 360 and manufactured by 3D printing. This refrigerator consists of thermoelectric module as cooling generator along with insulated cabin, thermostat and charging unit. Thermoelectric elements perform the same cooling function as Freon-based vapour compression or absorption refrigerators. The design of the refrigeration is based on the principle of thermoelectric module (i.e. Peltier effect) to create a hot side and a cold side. The cold side of the thermoelectric module is used for refrigeration purposes. On the other hand, the heat from the hot side of the module is rejected to the surroundings with the help of heat sinks and fan. Based on the heat load calculations, the thermoelectric module is selected. The system is fabricated and experimentally tested for the time taken to cool to the required temperature. The results showed that the system can maintain the temperature of approximately 10 °C with minimum power consumption of 64 Watt.

Lumsdenite, NaCa3Mg2(As3+V4+2V5+10As5+6O51)·45H2O, a new polyoxometalate mineral from the Packrat mine, Mesa County, Colorado, USA

ABSTRACT Lumsdenite (IMA 2018–092), ideally NaCa3Mg2(As3+V4+2V5+10As5+6O51)·45H2O, is a rare new polyoxometalate mineral from the Packrat mine, Gateway district, Mesa County, Colorado, USA. Crystals of lumsdenite occur as blades up to 0.2 mm in length, commonly growing in sprays. The crystals are dark green blue, with a green-blue streak. The mineral occurs on asphaltum, associated with montroseite- and corvusite-bearing sandstone. Other secondary minerals found in close association with lumsdenite are gypsum, huemulite, rösslerite, and at least two other potentially new minerals. Lumsdenite is optically biaxial (–), with α 1.617(2), β 1.651(5), and γ 1.675(5) in white light. The pleochroism scheme for lumsdenite is X = greenish yellow, Y = dark greenish blue, Z = greenish blue; X << Z < Y. The mineral is triclinic, , with a 10.3490(5), b 17.6263(9), c 23.2556(16) Å, α 82.208(6), β 88.351(6), γ 81.702(6)°, V 4158.8(4) Å3, and Z = 2. The strongest four powder diffraction lines for lumsdenite are [dobs Å(I)(hkl)]: , 14.86(80)(011), 17.30(44)(010), and 10.22(32)(100). The atomic arrangement of lumsdenite contains the novel polyoxometalate heteropolyanion [As3+V4+,5+12As5+6O51] structural unit in lumsdenite, [As3+V4+25+10As5+6O51]11−, which has previously been found in four other minerals from the Packrat mine. The charge of the structural unit is balanced by the charge of the [NaCa3Mg2(H2O)31·14H2O]11+ interstitial complex. The name lumsdenite is for the location of the mine at the head of Lumsden Canyon.

Interpolyelectrolyte Complex Dissociation vs Polyelectrolyte Desorption from Oppositely Charged Surface upon Salt Addition.

The structure of complexes formed by oppositely charged polyelectrolytes and adsorbed layers on charged surfaces is sensitive to low-molecular-weight salt. Furthermore, if the concentration exceeds some threshold value, the complexes and adsorbed chains can be "dissolved". This is due to the screening of the electrostatic interactions between charged units. In the current paper, we perform a comparative analysis of "dissolution" (dissociation) of complexes and layers upon addition of salt. For this, the conventional Brownian dynamics of computer simulations is used. We demonstrate that the complex based on linear chains dissociates at lower salt concentration than that required for desorption of equivalent chains from an oppositely charged surface. The physical reason is the difference in the symmetry of the electric field, which binds the chains into the complex (layer). In the salt-free regime, the intensity of the electric field (and attractive force) between two linear chains decays with the distance R between them, like for two spherical objects, ∼R-2, if R is bigger than the characteristic size of the chain. On the contrary, the attractive force of the chain to the infinite surface does not depend on the distance to the surface (the electric field is constant). Therefore, if attractive forces in the condensed states of the two systems are equal, one needs to add more salt to screen the constant force than the decaying one. The computer simulation results on the adsorption of the chains were compared with the experimental data obtained for adsorption of cationic poly(4-vinylpyridine) on the surface of anionic liposomes. Good quantitative agreement was achieved.

Role of polyethylene oxide content in polypyrrole linear actuators

Current research on conducting polymer composite actuators has been mainly focused on achieving increased linear actuation with improved electrical, physical and chemical properties. Polyethylene oxide (PEO) has been shown to enhance both mechanical and electrical properties of conducting polymers at certain concentrations. However, as some of these effects peak off, the optimal concentration is difficult to determine. In this study, polypyrrole (PPy)-PEO composite films, doped with dodecylbenzene sulfonate, were electropolymerized from solutions with different concentrations of PEO. The obtained films were studied by atomic force microscopy (AFM), scanning electron microscopy (SEM), Raman, FTIR and energy dispersive X-ray spectroscopy (EDX). Electrochemical impedance spectroscopy (EIS) and modified scanning ionic conductance microscopy (mSICM) allowed the determination of electronic and ionic conductivities of the samples. Their electro-chemo-mechanical deformations (ECMD) were investigated under cyclic voltammetry. In aqueous electrolyte, the samples showed expansion/contraction during reduction/oxidation, respectively (cation-driven), while opposite behaviour - expansion/contraction during oxidation/reduction (anion-driven) behaviour was observed in propylene carbonate solutions. These films obtained from solutions with a PEO content of 5% showed the highest deformations (strain and stress). They also presented the highest ionic and electronic conductivities and redox charge density. The ECMD deformation per unit of redox charge was much higher in PC solutions than in aqueous solutions: more PC molecules are exchanged for osmotic balance per unit of redox charge.

Collapse–Decollapse of Thermosensitive Polyelectrolyte Gels in Aqueous Media

The effect of temperature on water sorption by gels based on the copolymers of N-isopropylacrylamide with sodium p-styrene sulfonate containing 1, 3, and 5 mol % of charged monomer units is studied in aqueous media in the presence of salt (NaCl, KCl) or urea. It is shown that the incubation of gels in salt solutions leads to compression of the gels. With increasing temperature, the collapse of gels is observed in all studied media. The difference in the gel collapse temperature in water and salt solution increases with an increase in the fraction of charged units in the polymer gel network and in the salt concentration in the solution. With a return temperature decrease and gel decollapse, the mass of all gels in salt solutions (0.5–5.0 wt %) is completely restored. The incubation of gels in aqueous solutions of urea (0.5–5.0 wt %) has practically no effect on water sorption by gels before the collapse and the collapse temperature. However, the degree of swelling of polyelectrolyte gels during decollapse caused by a temperature decrease is much lower than the initial value, in contrast to the completely reversible swelling of the poly(N-isopropylacrylamide) gel under similar conditions.

Electrically evoked stapedial reflex threshold assessment among malaysian cochlear implant users: Comparisons between different stimulus rates

Background and Objective: Cochlear implant (CI) mapping can be carried out using subjective or objective assessments. Electrically evoked stapedial reflex threshold (ESRT) measurement is one of the valuable objective assessments to establish appropriate CI maps. As such, more research efforts are required to determine the most optimum recording protocols when recording ESRT. In the present study, the effect of stimulus rate on ESRT among CI users was determined. It was also of interest to know which stimulus rate would produce the optimum correlation with the behavioral most comfortable level (MCL) results. Materials and Methods: In this study that employed a repeated measures design, 12 Malaysian CI users were enrolled (mean age = 22.3 ± 13.3 years, ranging from 14 to 51 years). MCL and ESRT (measured in charge units, qu) were measured for three representative electrodes (electrode 2, electrode 6, and electrode 11) using 1000 pps and 2000 pps rates. Results: ESRT was 100% recordable for electrodes 2 and 6. For electrode 2, the mean ESRT values were 20.5 qu and 20.4 qu for 1000 pps and 2000 pps, respectively. While for electrode 6, the mean ESRT was 25.4 qu for 1000 pps and 25.7 for 2000 pps. Excellent correlations were found between ESRT and MCL for both stimulus rates (intraclass correlation ≥0.90). Conclusion: Both stimulus rates were found to produce comparably good ESRT results. Since ESRT and MCL values were highly correlated with each other, the objective ESRT testing can be used conveniently to predict the behavioral MCL, particularly among difficult-to-test patients.

Signal processing application for vibration generated by blasting in tunnels

Purpose. To study the vibrations waves generated by blasting in a tunnel using the signal processing tools. Methodology. Field tests are carried out to measure vibration wave during blasting operations at different locations in the tunnel and its immediate environment. Results of the measurements are processed by the autocorrelation method, which consists of filtering based on signal shape recognition. A comparison is accomplished between the peak particle velocities (PPV) measured and those obtained after filtering. Findings. The results obtained after filtering gave a significant reduction in PPV of the measured vibration amplitudes in comparison to those obtained after treatment for the three components: longitudinal, transversal and vertical ones. Good knowledge of vibration source is important for amplitude attenuation regarding the observed difference between the recorded seismogram during explosion of a single unit charge and other standard explosions. Originality. The work introduces signal processing methods for filtering vibration signals related to blasting, which is insufficiently studied. Practical value. This study shows that the treatment of blasting vibrations by a filtering method should reduce the peak velocity of the particles by separating the signals and eliminating the interference in the initial signal.

An improved market mechanism for energy storage based on flexible state of energy

In this paper, a new operation mode is proposed for energy storage, based on which an improved semi-centralized mechanism is proposed for energy storage to participate in the day-ahead energy market. The new operation mode, namely the flexible state-of-energy (SOE) mode, is proposed based on the previous fixed SOE mode, under which the final SOE of energy storage at the end of the last period of the scheduling horizon is no more limited to a predefined value. Accordingly, the value-of-SOE curve is introduced to quantify the deviation cost of the final SOE from the predefined value. Under the proposed market mechanism, energy storage submits to the system operator the unit charging and discharging cost and the value-of-SOE curve. The system operator dispatches the charging and discharging power of energy storage according to the data submitted and system operation. A comparative analysis is conducted in the case studies, and results demonstrate that the proposed mechanism is efficient in further realizing the flexibility potential of energy storage and reducing the total cost of power system.

Design and implementation of adaptive battery charging method considering the battery temperature

Today, batteries are widely used in mobile devices, vehicles and military applications. Batteries meet the energy needs of the equipment on the vehicle in military vehicles which is one of the application areas. During the military vehicle is stationary, the vehicle engine must not work for camouflage. Therefore, it needs a battery charge circuit. Controlled charging/discharging of the batteries is very important for the cycle life and safety of the batteries. Many conventional battery chargers units charge it without considering the battery temperature. In this study, adaptive battery charging method design and circuit is taken into consideration, considering the battery temperature. The adaptive battery charging algorithm has been applied to charge the batteries of military vehicles and in accordance with military standards (MIL-STD-1275-E voltage surges and MIL-HDBK-454B electronic equipment standard). In this study, experiments with different charge rates have been made and conventional constant current and constant voltage method and proposed adaptive battery charging method result are compared. Experimental results show that the battery temperature decreases 15°C with the proposed charging method. This adaptive battery charging method has been shown to prevent overheating of the battery.

Servis Sorumlu Hemşirelerinin Dönüşümcü Liderlik Davranışları ve Hemşirelerin Motivasyon Durumları

Servis Sorumlu Hemşirelerinin Dönüşümcü Liderlik Davranışları ve Hemşirelerin Motivasyon Durumları

Air purification system

An air purification system based on the use of specialized catalytic filling, designed to reduce high concentrations of hydrogen sulfide and volatile organic compounds is represented. The system is a 20 or 40 foot heated sea container in which two catalytic charge units are located: one is a working and the other is a reserve. Each block contains one cleaning step with a specialized ferrous charge.

Outsourcing Strategy With Patent Licensing in an Electronic Product Supply Chain

An electronic product like a smartphone might involve hundreds of thousands of patents. The risks caused by infringement make it necessary for enterprises to consider patent licensing when outsourcing production activities in the electronics industry. This paper studies the outsourcing strategy considering patent licensing in an electronic product supply chain composed of a patent-holding firm, an original equipment manufacturer (OEM) and a contract manufacturer (CM). In addition to outsourcing manufacturing to the CM, OEM also considers outsourcing the patent license obtaining as well. We construct two outsourcing modes, called Turnkey and Consignment. No matter under which outsourcing mode, the patent-holding firm will charge unit royalty and a fixed fee paid in a lump sum. The results show that the OEM tends to choose Consignment without considering fixed fees, while the CM prefers Turnkey. When considering fixed fees, the patent-holding firm could align their preferences by coordinating fixed fees borne by OEM and CM. What’s more, considering the environmental pollution caused by the production of electronic products, both strategies may lead to higher social welfare than the other strategy.

A Study of Cryostructuring of Polymer Systems. 53. The “Abnormal” Character of Variations in the Properties of Chitosan-Containing Composite Poly(vinyl alcohol) Cryogels upon Repeated Freezing–Defrosting

Complex cryogels have been obtained by freezing mixed aqueous solutions of poly(vinyl alcohol) (PVA) and chitosan hydrochloride (ChHC) at –20°С followed by incubation of frozen samples for 12 h and defrosting by heating at a rate of 0.03°С/min. Treatment of the cryogels with ammonia vapor has transformed ChHC into chitosan base, which has the form of a dispersed filler incorporated into the continuous phase of the obtained composite cryogels. Variations in the elasticity modulus of these composites upon repeated freezing–defrosting have been revealed to have an “abnormal” character. Unlike the tendency toward a substantial increase in this parameter well-known for various unfilled PVA cryogels, the rigidity of the obtained chitosan-containing composites remains almost unchanged for, at least, four subsequent cycles of the cryogenic treatment. It has been shown that one of the main reasons for this is the presence of low-molecular-weight electrolytes in a composite cryogel—NH4OH, which results from neutralization of ChHC with ammonia and exhibits a salting-in effect, and NH4OH, which can deprotonate OH groups of PVA and chitosan, thereby leading to the appearance of negatively charged units in polymer chains and, as a consequence, to their repulsion. When water-soluble components, i.e., the sol fraction, are washed from such a chitosan-containing composite cryogel, its susceptibility to the strengthening effect of repeated freezing–defrosting cycles is restored. The influence of the repeated cryogenic treatment on the physicomechanical and thermomechanical properties of these and a number of model unfilled and composite cryogels and the morphology of their macropores has been studied.

EV Aggregators and Energy Storage Units Scheduling into Ancillary Services Markets: The Concept and Recommended Practice

In this paper, optimization of Electric Vehicle (EV) batteries and dedicated energy storage unit charging profiles were conducted for the sake of bidding into day-ahead ancillary service markets. The aim of the optimization is to provide the maximum operational profits for both the EV aggregator and dedicated energy storage unit administrator. Ancillary service algorithms were then introduced to simulate the response of the EV batteries and dedicated energy storage units. Results showed that the usage of dedicated energy storage units for bidding into the ancillary services markets is more profitable than the case of operating an EV aggregator.

Superhydrophilic and underwater superoleophobic coatings on the basis of grafted polyelectrolytes on a textured aluminum surface

Water-loving compounds are usually used to prepare superhydrophilic and underwater superoleophobic surfaces. Hydrophilic polymers especially polyelectrolytes which contain the charged units in their structure is one of the perspective classes for the creation of materials with superhydrophilic properties. In this work, grafted polyelectrolytes based on quaternized N,N-dimethylaminoethyl methacrylate and sodium methacrylate were synthesized on the textured aluminum surface with an attached anchor layer (polyglycidyl methacrylate) and the initiator (2-bromo-2-methylpropionyl bromide) using surface-initiated atom transfer radical polymerization. The texturing of aluminum surface was performed using sequential etching in alkali and acid solutions. The lyophilic properties of grafted polyelectrolytes were studied by contact angle measurements using the “sessile drop” and “captive bubble” methods. The resulting coatings exhibit superhydrophilic properties due to quaternized ammonium and carboxyl charged groups in the grafted polyelectrolytes. Specifically, the coatings show complete wetting with water, stable aerophobicity and oleophobicity in aqueous media, and the demonstrated contact angles are greater than 170° for long contact times. It has been shown that grafting of polyelectrolytes prevents the sorption of nonpolar organic pollutants on the modified surface.

Application of Rukhsah Solat by Malaysian Health Care Workers

Introduction: Solat (Islamic prayer) is a mandatory act of worship to be performed by Muslim doctors albeit time constraint and dire condition while treating or resuscitating critical patients. Islam has allowed leniency (rukhsah) for such group to fulfill this obligation while executing their responsibility in saving life. This study aims to analyze current practice of rukhsah solat by Muslim health care workers (HCWs) during their critical call of duty.Methods: This is a qualitative study. Document analysis from Islamic jurisprudence (fiqh) references and interviews with expert from both Islamic scholars and clinicians was conducted. Field observation was done to ascertain the practice among HCWs.Results: The study identifies a few indication and reasons for HCWs to apply rukhsah solat, which are determined by their scope and place of duty as well as critical situation of patients. Those who are assigned for prolong operation or taking charge of intensive care unit, emergency and trauma department and labour rooms tend to practice rukhsah solat while on duty. Among types of rukhsah solat performed by HCWs are combining solat (jamak) and replacing solat outside the prayer time (qada’) once they finish the critical task or operation.Conclusion: This study also analyzes current practice of rukhsah solat by HCWs in the light of Islamic jurisprudence (fiqh), hence suggesting recommendation to facilitate such practice to be more bearable among HCWs in accordance to the Objective of Syariah (Maqasid Syariah) and Islamic legal maxim (Qawaid Fiqhiyyah).International Journal of Human and Health Sciences Supplementary Issue: 2019 Page: 40