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Understanding interactions at the interfaces of carbon with ionic liquids (ILs) is crucially beneficial for the diagnostics and performance improvement of electrochemical devices containing carbon as active materials or conductive additives in electrodes and ILs as solvents or additives in electrolytes. The interfacial interactions of three typical imidazolium-based ILs, 1-alkyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide (AMImTFSI) ILs having ethyl (C2), butyl (C4) and octyl (C8) chains in their cations, with highly oriented pyrolytic graphite (HOPG) were studied in-situ by electrochemical scanning tunneling microscopy (EC-STM). The etching of HOPG surface and the exfoliation of graphite/graphene flakes as well as cation intercalation were observed at the HOPG/C2MImTFSI interface. The etching also takes place in C4MImTFSI at −1.5 V vs Pt but only at step edges with a much slower rate, whereas C8MIm+ cations adsorbs strongly on the HOPG surface under similar conditions with no observable etching or intercalation. The EC-STM observations can be explained by the increase in van der Waals interaction between the cations and the graphite surface with increasing length of alkyl chains.

Scanning tunneling microscopy (STM) has proved to be a prime tool to characterize the atomic structure of crystal surfaces under UHV conditions. With the development of high-pressure scanning tunneling microscopy (HP-STM), the scope of this technique has been largely extended, as new structures were found to occur under gas phase chemical potentials achieved under ambient conditions. Particularly interesting is the substantial restructuring of initially flat and stable surfaces into new orientations by formation of nanoclusters. Here we discuss the possible generality of this phenomenon by analyzing cases where atomically flat surfaces of certain transition metals undergo such changes in the presence of CO at room temperature (RT) while some remain unchanged. From our analysis we argue that such changes can be predicted from thermodynamic data published in the literature, particularly from the difference in adsorption energy on low-and high-coordination sites, like terrace and step sites, which can be obtained from thermal desorption spectroscopy (TDS) measurements, and possibly also from theoretical calculations. For the vicinal surfaces with high Miller indices, changes in the repulsive elastic interactions between the ordered steps due to adsorbates may also play an important role.

In the version of this Article originally published, the author Baran Eren was mistakenly affiliated with the Harbin Institute of Technology, China; it has now been corrected to Materials Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.

Bimetallic and multi-component catalysts typically exhibit composition-dependent activity and selectivity, and when optimized often outperform single-component catalysts. Here we used ambient-pressure X-ray photoelectron spectroscopy (AP-XPS) and in situ and ex situ transmission electron microscopy (TEM) to elucidate the origin of composition dependence observed in the catalytic activities of monodisperse CoPd bimetallic nanocatalysts for CO oxidation. We found that the catalysis process induced a reconstruction of the catalysts, leaving CoOx on the nanoparticle surface. The synergy between Pd and CoOx coexisting on the surface promotes the catalytic activity of the bimetallic catalysts. This synergistic effect can be optimized by tuning the Co/Pd ratios in the nanoparticle synthesis, and it reaches a maximum at compositions near Co0.24Pd0.76, which achieves complete CO conversion at the lowest temperature. Our combined AP-XPS and TEM studies provide direct observation of the surface evolution of the bimetallic nanoparticles under catalytic conditions and show how this evolution correlates with catalytic properties.

Ambient-pressure X-ray photoelectron spectroscopy (XPS) was used to investigate the reactions of CO, H2, and their mixtures on Co foils. We found that CO adsorbs molecularly on the clean Co surface and desorbs intact in vacuum with increasing rate until ∼90°C where all CO desorbs in seconds. In equilibrium with 100 mTorr gas, CO dissociates above 120°C, leaving carbide species on the surface but no oxides, because CO efficiently reduces the oxides at temperatures ∼100°C lower than H2. Water as impurities or produced by reaction of CO and H2 efficiently oxidizes Co even at room temperature. Under 97:3 CO/H2 mixture and with increasing temperatures, the Co surface becomes more oxidized and covered by hydroxyl groups until ∼150°C where surface starts to get reduced, accompanied by carbide accumulation indicative of CO dissociation. A similar trend was observed for 9:1 and 1:1 mixtures, but surface reduction begins at higher temperatures. (Figure Presented).

This article reviews Anna McKay's "Female Devotion and Textile Imagery in Medieval English Literature," published by D. S. Brewer in 2024.

OBJECTIVE: Spinal metastases may only affect the bone tissue and result in spinal instability or may additionally result in epidural compression, leading to neurological deficits. Surgery has emerged as a popular method in treating metastatic epidural spinal cord compression (MESCC) due to the advances in surgical techniques and instrumentation. In this study, we evaluated patients with MESCC regarding neurological status, pain status, and survival rates, and presented our experience managing MESCC. PATIENTS AND METHODS: Clinical and radiographic records of 53 patients diagnosed with MESCC between January 2011 and March 2017 were retrospectively evaluated. The study included patients with a pathological diagnosis of primary cancer, those who complained of spinal metastasis, and those who had indications of MESCC on Magnetic Resonance Imaging (MRI). Bone structure and spinal stability were evaluated using assessed Computed Tomography (CT), and metastatic spread was considered using assessed Positron Emission Tomography (PET) in suitable cases. For each patient, the presence of a tumor compressing the spinal cord, age, gender, preoperative, and postoperative American Spinal Injury Association scores (ASIA), Tokuhashi prognostic score (TPS), affected spinal segment, pathological diagnosis, preoperative, and postoperative Visual Analog Scale (VAS), the status of spinal stability, follow-up period, and complications were evaluated. RESULTS: Forty-five patients (82.2% of them were women) underwent surgery with a mean age of 58.29 ± 15.14 years. The most frequent type of primary tumor was multiple myeloma (33.9%), followed by lung (24.6%), gastric (7.5%), and prostate (5.7%). The most common site of lowed by lumbar (24.5%), multiple (24.5%), and cervical (5.7%). The analysis indicated that a significant difference was found between the survival rates of the TPS categories. CONCLUSIONS: Common symptoms of MESCC include spinal pain and neurological deficit below the level of the injury. Prompt surgical treatment followed by oncological treatment leads to significant neurological recovery, more prolonged survival, pain relief, and improved quality of life in patients with a short survival time. Oncological treatments, including radiotherapy (RT), should be recommended after surgical treatment. [ABSTRACT FROM AUTHOR]

Covid-19 pandemisi ile birlikte dünya genelinde tek kullanımlık yüz maskesi kullanımı büyük artış göstermiştir. Bu kullanılmış maskelerin artışı çevre için büyük tehdit oluşturmakla birlikte, bertaraf edilmesi de problem olarak ortaya çıkmıştır. Bu problemin çözümü için yüz maskelerinin zemin iyileştirmede kullanımının bir yöntem olacağı düşünülmüştür. Bu nedenle 0,5*3 cm boyutlarındaki yüz maskeleri %0,2-0,4-0,6-0,8-1 oranlarında düşük plastisiteli kil ile karıştırılarak Bender element ve Serbest basınç deneylerine tabi tutulmuştur. Yapılan serbest basınç deney sonuçlarına göre yüz maskesinin belirli bir orana kadar dayanımı arttırdığı, daha sonra ise dayanımı düşürdüğü görülmüştür. Yapılan bender element testlerine göre maske liflerinin yüksek birim hacim ağırlıkta kayma dalgası hızının azalmasına ancak düşük birim hacim ağırlığındaki numunelerde kayma dalgası hızının öncelikle arttığı, daha sonra azaldığı görülmüştür.

Bu araştırmanın amacı 2014-2018-2022 Dünya Kupası’nda grup ve grup sonrasında toplam 192 maçta atılan 512 golün analizini incelemektir edilmiştir. Çalışma verileri erişime açık olan FIFA’nın resmî web sitesinden (www.fifa.com) ve YouTube kanalından elde edilmiştir. Atılan gollerin analizi, gol sayısına; kaleye olan uzaklığa, gollerin dakikalara göre zamanlamasına, açık oyun ve duran toplara ve futbolcuların mevkilerine göre yapılmıştır. Elde edilen veriler SPSS 22 paket programına kaydedilmiş̧, tanımlayıcı istatistik kullanılarak, ortalama ve yüzde değerleri hesaplanmıştır. Sonuç olarak, gollerin atıldığı 15 dakikalık zaman diliminde, son üç turnuvada da gollerin çoğunun ikinci yarı ve oyunun sonlarına doğru atıldığı özellikle de 2022 Dünya Kupasındaki uzatma periyodunda (91-105. dk) en fazla golün atıldığı tespit edilmiştir. Gollerin atış şekline bakıldığında, kendi kalesine atılan gollerde ve duran toplarda en fazla golün 2018 Dünya Kupasında gerçekleştiği, 2014-2022’de ise açık oyundan atılan gol sayısında artış meydana geldiği tespit edilmiştir. Sonuç olarak antrenörler oyuncularının gol yollarında daha fazla etkili olması adına gerek duran top gerekse açık oyunla ile ilgili fonksiyonel ve taktiksel çalışmalara ağırlık vermeli, oyun ve oyuncu değişikliklerindeki zamansal ve taktiksel stratejiyi iyi uygulayabilmeli ve uzatma dakikalarına kadar fiziksel bozulma yaşamadan savunma yapısını koruyarak oyunu bir bütün olarak oynatmalıdır.

Recently, large-scale, Web-based service marketplaces, where many small service providers compete among themselves in catering to customers with diverse needs, have emerged. Customers who frequent these marketplaces seek quick resolutions and thus are usually willing to trade prices with waiting times. The main goal of this paper is to discuss the role of the moderating firm in facilitating information gathering, operational efficiency, and communication among agents in service marketplaces. Surprisingly, we show that operational efficiency may be detrimental to the overall efficiency of the marketplace. Furthermore, we establish that to reap the 'expected' gains of operational efficiency, the moderating firm may need to complement the operational efficiency by enabling communication among its agents. The study emphasizes the scale of such marketplaces and the impact it has on the outcomes. Key words: service operations; fluid models; asymptotic analysis; large games; noncooperative game theory History: Received August 5, 2009; accepted January 18, 2012, by Yossi Aviv, operations management. Published online in Articles in Advance June 15, 2012., 1. Introduction Recently, large-scale, Web-based service marketplaces, where many small service providers (agents) compete among themselves in catering to customers with diverse needs, have emerged. Customers who frequent these marketplaces [...]

Objective: Cleft lip and palate is one of the most common birth defects. It may result in anatomical differences, feeding, dental, hearing, and speech problems. Many speech problems occur due to insufficient velopharyngeal closure, and this causes inappropriate air leakage to the nasal cavity resulting in hypernasality. In such speech, the obstruent sounds are weakened or distorted. The aim of this study is to analyze the acoustic properties of Turkish fricatives of children with cleft lip and palate having hypernasality. Methods: For this purpose, duration, voicing duration, center of gravity (M1), skewness (L3), and kurtosis (L4) values of sibilants (/s, z, ʃ, ʒ/) were measured. Each sibilant was located word-initial position within a sentence. Four children with cleft palate with hypernasality and 4 children without cleft palate participated in the study. All the participants were Turkish native speakers, and their age range was 10-12. The data was analyzed with R and linear mixed model. Results: It has been seen that the duration of target sounds is longer for children with cleft palate having hypernasality. Moreover, M1 is found lower for these participants than those without hypernasality. Although L3 does not show any discrepancy for both groups, L4 is lower for the children with cleft palate having hypernasality. Conclusion: It has been found that hypernasality affects the duration, M1 and L4 of target sibilant sounds. All results have shown that children with hypernasality need more time and prefer back articulation to create the intra-oral pressure; however, they canno create enough turbulence required for fricatives.

Distribution utilities responsible for supplying electricity face challenges in maintaining continuity of power supply and serving end consumers. Locating faults in the distribution network is a major challenge since faults can cause long-duration disruptions in power supply. Therefore, effective fault localization techniques, particularly for High Impedance Faults (HIFs), have become an area of focus. These faults are not detected by conventional protection equipment as they have currents with magnitudes similar to loads in the distribution network. Despite the considerable research efforts devoted to this issue, there is still no universal solution to locate such faults. Thus, this paper proposes a methodology that can identify the branch of HIFs in the distribution network and determine its location precisely. The proposed technique uses traveling wave method, Discrete Wavelet Transform (DWT), and Artificial Neural Network (ANN) as machine learning method. The proposed method has undergone numerous tests considering various inception angles, load variations, and different networks to prove its robustness and effectiveness. The results show that the proposed method is promising, with a high accuracy for determining faulty section and a low error ratio for fault distance calculations.