Serious Drawbacks In Terms Research Articles

Methemoglobin-albumin clusters for cyanide detoxification

Sodium nitrite (NaNO2) is a universal antidote for patients with cyanide poisoning. However, its use has serious drawbacks in terms of efficacy and safety. Herein, we present a promising antidote: methemoglobin (metHb)-albumin clusters. The metHb-albumin cluster is made by a metHb core wrapped by covalently bound human serum albumin. Spectral analyses proved that the metHb-albumin clusters possessed cyanide-binding properties similar to those of naked metHb. In vitro cell experiments showed that metHb-albumin clusters prevented the cyanide-induced inhibition of cytochrome c oxidase activity, resulting in a strong cytoprotective effect. In mice subjected to cyanide poisoning, metHb-albumin clusters reduced mortality and alleviated metabolic acidosis, while maintaining the activity of cytochrome c oxidase in organs; their efficacy was better than that of NaNO2. Furthermore, the oxygen carrying capacity was maintained in poisoned mice treated with metHb-albumin clusters and was low in those treated with NaNO2. These results indicate that metHb-albumin clusters could be a more effective and safer antidote against cyanide poisoning than NaNO2.

Bütçe Hakkının Cumhurbaşkanlığı Sistemindeki Görünümü ve Latin Amerika Ülkeleri ile Mukayesesi

Türkiye’de 2017 yılında 6771 sayılı Kanun ile yapılan Anayasa değişikliği neticesinde hükûmet sistemi değişmiş ve başkanlık hükûmet sistemine geçilmiştir. Bu değişiklikile beraber bütçe sistemi de değişmiş ve yürütmenin bütçenin tasdiki açısından ciddi güç kazandığı görülmüştür. Bu durumun kuvvetler ayrılığı, denge-denetleme vebütçe hakkı açısından ciddi sakıncaları doğuracağı düşünülmüştür. Başkanlık sistemini uygulayan diğer devletlerle mukayesesi için Latin Amerika ülkeleri seçilmiş, buülkelerin bütçe hakkı açısından ortak özellikleri ortaya konmuş ve Türkiye’nin yeni sistemi ile mukayesesi sağlanmıştır. Netice itibariyle, Türkiye’nin, yürütmenin güçlüolduğu Latin Amerika ülkelerine benzer bir sisteme geçiş yaptığı görülmüş, yasamanın güçlendirilmesine yönelik tavsiyeler vurgulanmıştır.

Toughening of Petroleum Based (DGEBA) Epoxy Resins with Various Renewable Resources Based Flexible Chains for High Performance Applications: A Review

The petroleum based diglycidyl ether of bisphenol A (DGEBA) epoxy resin is one of the most extensively used epoxy resins for various industrial applications such as paints, coatings, adhesives, and structural applications, owing to its excellent mechanical and thermal properties, low curing shrinkage, and good chemical resistance. However, the serious drawbacks in terms of brittleness or poor fracture energy significantly restricted its extensive utilization. Various renewable resources based flexible chains were used to blend with DGEBA for toughening and to significantly improve the fracture properties without sacrificing the mechanical properties. This review mainly focuses on toughening of DGEBA with various renewable polymers and the effect of its concentration on its toughening mechanism.

A Printable Organic Electron Transport Layer for Low‐Temperature‐Processed, Hysteresis‐Free, and Stable Planar Perovskite Solar Cells

Despite recent breakthroughs in power conversion efficiencies (PCEs), which have resulted in PCEs exceeding 22%, perovskite solar cells (PSCs) still face serious drawbacks in terms of their printability, reliability, and stability. The most efficient PSC architecture, which is based on titanium dioxide as an electron transport layer, requires an extremely high‐temperature sintering process (≈500 °C), reveals hysterical discrepancies in the device measurement, and suffers from performance degradation under light illumination. These drawbacks hamper the practical development of PSCs fabricated via a printing process on flexible plastic substrates. Herein, an innovative method to fabricate low‐temperature‐processed, hysteresis‐free, and stable PSCs with a large area up to 1 cm2 is demonstrated using a versatile organic nanocomposite that combines an electron acceptor and a surface modifier. This nanocomposite forms an ideal, self‐organized electron transport layer (ETL) via a spontaneous vertical phase separation, which leads to hysteresis‐free, planar heterojunction PSCs with stabilized PCEs of over 18%. In addition, the organic nanocomposite concept is successfully applied to the printing process, resulting in a PCE of over 17% in PSCs with printed ETLs.

Assessment of low energy X-ray imaging for magnetic and gold nanoparticles

Introduction Gold and magnetic nanoparticles (NPs) are already used as contrast agents in CT and MRI diagnosis respectively, as well as in hyperthermia treatments. In both cases it is very important to be able to determine in vivo the distribution of the NPs. This can be done by radiolabeling the NPs or via MRI. These methods however present serious drawbacks in terms of cost and complexity. Purpose The purpose of this study is to explore and standardize a procedure of in vivo X-ray imaging for magnetic and gold NPs for diagnostic and pre-therapeutic purposes, using this low-cost, simple, readily available technology. Materials and methods The measurements were carried out on a prototype bench top x-ray system, consisting of an X-ray tube of a maximum beam energy of 80 keV and a minimum focal spot of 33 μm and of a CMOS detector with an active area of 12 × 12 cm and a spatial resolution of 0.1 mm. NPs samples of concentrations ranging between 1 and 500 mg of substance/ml were studied and compared with standard iodine solutions. Results All substances are found to present significant contrast enhancement properties and are used to create a standardized imaging procedure with respect to their concentrations. Gold nanoparticles are easily seen in lower concentrations and dual energy subtraction offers a greater differentiation in the observed attenuation properties. Localization and distribution information can be obtained in vivo through X-ray imaging. Conclusion A standardized procedure of in vivo X-ray imaging is set up for magnetic and gold NPs for diagnostic and pre-therapeutic purposes. Disclosure There is no relationship to be disclosed that may bias this presentation.

Flexible Nonvolatile Polymer Memory Array on Plastic Substrate via Initiated Chemical Vapor Deposition.

Resistive random access memory based on polymer thin films has been developed as a promising flexible nonvolatile memory for flexible electronic systems. Memory plays an important role in all modern electronic systems for data storage, processing, and communication; thus, the development of flexible memory is essential for the realization of flexible electronics. However, the existing solution-processed, polymer-based RRAMs have exhibited serious drawbacks in terms of the uniformity, electrical stability, and long-term stability of the polymer thin films. Here, we present poly(1,3,5-trimethyl-1,3,5-trivinyl cyclotrisiloxane) (pV3D3)-based RRAM arrays fabricated via the solvent-free technique called initiated chemical vapor deposition (iCVD) process for flexible memory application. Because of the outstanding chemical stability of pV3D3 films, the pV3D3-RRAM arrays can be fabricated by a conventional photolithography process. The pV3D3-RRAM on flexible substrates showed unipolar resistive switching memory with an on/off ratio of over 10(7), stable retention time for 10(5) s, excellent cycling endurance over 10(5) cycles, and robust immunity to mechanical stress. In addition, pV3D3-RRAMs showed good uniformity in terms of device-to-device distribution. The pV3D3-RRAM will pave the way for development of next-generation flexible nonvolatile memory devices.

Geopolymers as potential repair material in tiles conservation

The restoration materials currently used to fill gaps in historical architectural tiles (e.g. lime or organic resin pastes) usually show serious drawbacks in terms of compatibility, effectiveness or durability. The existing solutions do not fully protect Portuguese faience tiles (azulejos) in outdoor conditions and frequently result in further deterioration. Geopolymers can be a potential solution for tile lacunae infill, given the chemical–mineralogical similitude to the ceramic body, and also the durability and versatile range of physical properties that can be obtained through the manipulation of their formulation and curing conditions. This work presents and discusses the viability of the use of geopolymeric pastes to fill lacunae in tiles or to act as “cold” cast ceramic tile surrogates reproducing missing tile fragments. The formulation of geopolymers, namely the type of activators, the alumino-silicate source, the quantity of water required for adequate workability and curing conditions, was studied. The need for post-curing desalination was also considered envisaging their application in the restoration of outdoor historical architectural tiles frequently exposed to adverse environmental conditions. The possible advantages and disadvantages of the use of geopolymers in the conservation of tiles are also discussed. The results obtained reveal that geopolymers pastes are a promising material for the restoration of tiles, when compared to other solutions currently in use.

Distributed multi‐agent information filtering—A comparative study

AbstractInformation filtering is a technique to identify, in large collections, information that is relevant according to some criteria (e.g., a user's personal interests, or a research project objective). As such, it is a key technology for providing efficient user services in any large‐scale information infrastructure, e.g., digital libraries. To provide large‐scale information filtering services, both computational and knowledge management issues need to be addressed. A centralized (single‐agent) approach to information filtering suffers from serious drawbacks in terms of speed, accuracy, and economic considerations, and becomes unrealistic even for medium‐scale applications. In this article, we discuss two distributed (multi‐agent) information filtering approaches, that are distributed with respect to knowledge or functionality, to overcome the limitations of single‐agent centralized information filtering. Large‐scale experimental studies involving the well‐known TREC data set are also presented to illustrate the advantages of distributed filtering as well as to compare the different distributed approaches.

Rapid, simultaneous determination of headspace oxygen and moisture in pharmaceutical packages using μGC

The rapid, accurate determination of headspace oxygen and moisture in various pharmaceutical packages is important for both product packaging development and the implementation of new packaging technologies. Current headspace oxygen measurement techniques suffer from serious drawbacks in terms of potential sampling contamination, lengthy analysis times, and large required analysis volumes. In addition, relatively few techniques currently exist for the convenient determination of headspace moisture in packaging systems. Efforts herein focused on the development and application of a new method for the rapid and simultaneous determination of headspace oxygen and moisture in pharmaceutical packages using micro-gas chromatography (μGC). Studies showed that both headspace oxygen and moisture could be simultaneously quantified in <90 s on sample volumes of 50–100 μL by employing μGC with dual chromatographic analysis modules. Sampling issues common to manual syringe-based injections were also alleviated in the current studies by use of the built-in diaphragm pump sampling interface of the portable μGC system. The performance of the analytical approach was evaluated and shown to exhibit excellent linearity, accuracy, and precision for both analytes. High sensitivity for headspace oxygen was demonstrated, allowing for levels of oxygen as low as 0.03% to be accurately quantified. The subject method was applied to measure the headspace oxygen and moisture in pharmaceutical blister packaging and glass vials.

Transmutation characteristics of MA and LLFP in a fast reactor

Systematic studies were implemented to investigate the flexibility and attractive core concepts of MA and LLFP transmutation in fast reactors. The MA transmutation in the fast reactor core has no serious drawbacks in terms of core performance, provided that the homogeneous loading method can be employed with a small fraction of MA fuel (2~5wt%). The recycling of MA in the fast reactor is feasible from neutronic and thermal-hydraulic points of view. For FP transmutation, the introduction of target subassemblies using duplex pellets — a moderator annulus surrounding a Tc-99 core — gives the maximum transmutation rate of Tc-99 in the radial shield region of the fast reactor. The fast reactor has an excellent potential for transmuting MA and LLFP effectively. The fast reactor will be able to play an important role for reduction of environmental burden in future energy system.

Feasibility Studies on Plutonium and Minor Actinide Burning in Fast Reactors

Systematic parameter studies were implemented to investigate the basic characteristics [plutonium and minor actinide (MA)-burning rate, burnup reactivity loss, Doppler coefficient, sodium void reactivity, maximum linear heat rate, etc.] of plutonium and MA-burning fast reactors and also to clarify the feasibility of such plutonium and MA burner fast reactors. Highly enriched mixed-oxide (MOX) fuels and plutonium fuels without uranium were consideredfor plutonium-burning enhancement. It was found that plutonium consumption rates essentially depend on plutonium enrichment. Both burnup reactivity loss and Doppler coefficient are important criteria for highly enriched MOX fuel cores. Cores without uranium were found to consume the plutonium at a very large burnup rate close to the theoretically maximum value of 110 to 120 kg/TW · h(electric). The introduction of UO2 in an internal blanket is effective in enhancing the Doppler coefficient; it causes a minor increase in the sodium void reactivity in nonuranium cores. The MA transmutation in a fast reactor core has no serious drawbacks in terms of core performance, provided that the homogeneous loading method can be employed with a small fraction of MA fuel (∼5 wt%). Fast reactors have a strong potential for burning plutonium and MA effectively.

Public Transit Access for Disabled Persons in the United States

ABSTRACT Disabled persons in the United States often lack usable public transit. The two most common solutions put forth are lift equipped buses on a fixed route and demand-response paratransit systems. Both of these programs have serious drawbacks in terms of service provided and costs, but a combination of them can begin to resolve the problem of public transit for disabled persons. The arguments for and against the use of lift buses and paratransit systems are analyzed. A policy recommendation is made.