Single-molecule-resolution ultrafast near-field optical microscopy via plasmon lifetime extension

A recent study shows that: when a long lifetime particle is positioned near a plasmonic metal nanoparticle, lifetime of plasmon oscillations extends, but, "only" near that long-life particle [PRB 101, 035416 (2020)]. Here, we show that this phenomenon can be utilized for ultrahigh (single-molecule) resolution ultrafast apertureless (scattering) SNOM applications. We use the exact solutions of 3D Maxwell equations. We illuminate a metal-coated silicon tip, a quantum emitter (QE) placed on the tip apex, with a femtosecond laser. The induced near-field in the apex decays rapidly except in the vicinity of the sub-nm-sized QE. Thus, the resolution becomes solely limited by the size of the QE. As positioning of a QE on the tip apex is challenging, we propose the use of a newly-discovered phenomenon; stress-induced defect formation in 2D materials. When a monolayer, e.g., transition metal dichalcogenide (TMD) is transferred to the AFM tip, the tip indentation of 2D TMD originates a defect-center located right at the sharpest point of the tip; that is exactly at its apex. Moreover, the resonance of the defect is tunable via a voltage applied to the tip. Our method can equally be used for background-noise-free nonlinear imaging and for facilitating single-molecule-size chemical manipulation.Comment: 4 pages, 3 pages of references, 5 figure

System identification and model-based flight control system design for an agile maneuvring quadrotor platform

In this paper, we provide a system identification, model stitching and model-based flight control system design methodology for an agile maneuvering quadrotor micro aerial vehicle (MAV) technology demonstrator platform. The proposed MAV is designed to perform agile maneuvers in hover/low-speed and fast forward flight conditions in which significant changes in system dynamics are observed. As such, these significant changes result in considerable loss of performance and precision using classical hover or forward flight model based controller designs. To capture the changing dynamics, we consider an approach which is adapted from the full-scale manned aircraft and rotorcraft domain. Specifically, linear mathematical models of the MAV in hover and forward flight are obtained by using the frequency-domain system identification method and they are validated in time-domain. These point models are stitched with the trim data and quasi-nonlinear mathematical model is generated for simulation purposes. Identified linear models are used in a multi objective optimization based flight control system design approach in which several handling quality specifications are used to optimize the controller parameters. Lateral reposition and longitudinal depart/abort mission task elements from ADS-33E-PRF are scaled-down by using kinematic scaling to evaluate the proposed flight control systems. Position hold, trajectory tracking and aggressiveness analysis are performed, Monte-Carlo simulations and actual flight test results are compared. The results show that the proposed methodology provides high precision and predictable maneuvering control capability over an extensive speed envelope in comparison to classical control techniques. Our current work focuses on i) extension of the flight envelope of the mathematical model and ii) improvement of agile maneuvering capability of the MAV

Development of entrepreneurship scale for students of health management departmentSağlık yönetimi bölümü öğrencilerine yönelik girişimcilik ölçeğinin geliştirilmesi

Entrepreneurship comes into prominence in health sector more every day. Especially, rapidly growing population motivates the entrepreneurs in this sector and sets them off on different quests in order to offer better services in health sector. Therefore, educated individuals who can produce better and more qualified service in this sector, utilize the opportunities in the sector, take positive or negative risks and bring new perspectives into health management sector are required. The purpose of the present study is developing a valid and reliable scale which can measure the entrepreneurship levels of health management department students.    291 health management department students studying at Selcuk University Faculty of Health Sciences form the work group of the study. Findings related to the construct validity of the developed scale were handled via factor analysis. Principal component analysis presented that items of the scale accumulated under one single dimension. Cronbach alpha value was used for the reliability studies of the developed scale. Obtained findings revealed that the coefficient of internal consistency of the scale is at a high rate. Scale total scores presented no significant differences between students across genders.   ÖzetSağlık sektöründe girişimcilik gün geçtikçe önem kazanmaktadır. Özellikle hızla artan nüfus bu alandaki girişimcileri harekete geçirmekte ve sağlık sektöründe daha iyi hizmet sunabilmek için farklı arayışlara itmektedir. Dolayısıyla bu alanda daha iyi ve kaliteli hizmet üretebilen, sektördeki fırsatları değerlendirebilen, olumlu veya olumsuz tüm riskleri alabilen ve sağlık yönetimi sektörüne yeni bakış açıları getirebilen eğitimli bireylere ihtiyaç vardır. Bu araştırmanın amacı, sağlık yönetimi bölümü öğrencilerinin girişimciliklerini ölçebilecek geçerliliği ve güvenirliği kanıtlanmış bir ölçme aracı geliştirmektir.Araştırmanın çalışma grubunu Selçuk Üniversitesi Sağlık Bilimleri fakültesinde okuyan 291 sağlık yönetimi bölümü öğrencisi oluşturmuştur. Geliştirilen ölçeğin yapı geçerliliğine dair bulgular faktör analizi ile ele alınmıştır. Temel bileşenler analizleri göz önünde bulundurulduğunda ölçeğin maddelerinin tek bir boyutta toplandığı görülmüştür. Geliştirilen ölçeğin güvenirliğinde Cronbach alfa değerine bakılmıştır. Elde edilen bulgulardan hareketle ölçeğin iç tutarlılık katsayısının yüksek oranda olduğu görülmüştür. Ölçek toplam puanlarında, öğrencilerin cinsiyet değişkenine göre anlamlı farklar bulunamamıştır

A quantum emitter coated with graphene interacting in the strong coupling regime

We demonstrate the strong coupling of a quantum dot and a graphene spherical shell coating it. Our simulations are the exact solutions of 3D Maxwell equations. Interaction produces sharp hybrid modes, even when the two are off-resonant, which are voltage-tunable (continuously) in an 80 meV interval. Despite a voltage-tunable quantum dot, the coupling of the light to these "very sharp" plexcitonic resonances is an order of magnitude larger than its coupling to a quantum dot. Hence, our results are very attractive for sensing applications and graphene display technologies with sharper colors. Moreover, on a simple theoretical model, we explain why such sharp, highly tunable, resonances emerge.Comment: 7 pages, 7 figure

Evaluation of Development in the Children of Seasonal Agricultural Workers

Children of seasonal agricultural workers, are a group of migrants in Turkey where agricultural production is intense, having a significant part of the year in unhealthy habitats in agricultural areas and having access to services [1,2]. In this group, many temporary or permanent health problems may arise due to the conditions of accommodation and malnutrition [3]. Our aim is to assess the growth and development of children of seasonal agricultural workers. The study is a cross-sectional field study in the agricultural regions of Eski?ehir city and districts starting from 1 July 2017. In our study, children of 119 seasonal agricultural workers under the age of 18 were included. In the study, 11 different agricultural regions were visited and the height, weight, body mass index and head circumference of the children were measured and the percentile values were calculated. In the study group ; children of seasonal agricultural workers were 53 (44.5%) male and 66 (55.5%) female. Their ages ranged from 0 to 16 years with a mean of 7.37 ± 3.58 years. 29.4% of the children of seasonal agricultural workers had both height and weight measurements of 5P or less. Growth and development retardation is one of the important diseases among the children of seasonal agricultural workers

NOKTA DİRENÇ KAYNAK ELEKTROTLARINA TiC-Co KAPLAMANIN ETKİSİ

Nokta direnç kaynak yöntemi otomotiv endüstrisinde yaygın olarak kullanılmaktadır. Diğer kaynak yöntemlerine göre oldukça hızlı, ekonomik, güvenilir bir yöntemdir. Kaynak işlemi sırasında elektrotların iş parçalarına temas eden yüzeyinde lokal olarak yüksek sıcaklıklara çıkılmaktadır ve kaynak çevrimi boyunca da elektrotlar iş parçalarına belli bir basınç uygularlar. Basınç ve sıcaklık elektrot yüzeyinde deformasyon oluşturur. Nokta direnç kaynağında kullanılan Cu-Cr-Zr elektrotların ömürlerini uzatmak için kaplama işlemi uygulanmaktadır. Bu çalışmada, elektrotların uç yüzeylerine TiC-Co malzeme elektrospark yöntemiyle farklı kaplama parametrelerinde kaplanmış, böylece kaplamanın DP600 çelik saç çifti birleştirmesi özelliklerine etkisi araştırılmıştır

Real-world efficacy and safety of Ledipasvir + Sofosbuvir and Ombitasvir/Paritaprevir/Ritonavir ± Dasabuvir combination therapies for chronic hepatitis C: A Turkish experience

Background/Aims: This study aimed to evaluate the real-life efficacy and tolerability of direct-acting antiviral treatments for patients with chronic hepatitis C (CHC) with/without cirrhosis in the Turkish population. Material and Methods: A total of 4,352 patients with CHC from 36 different institutions in Turkey were enrolled. They received ledipasvir (LDV) and sofosbuvir (SOF)+/- ribavirin (RBV) ombitasvir/paritaprevir/ritonavir +/- dasabuvir (PrOD)+/- RBV for 12 or 24 weeks. Sustained virologic response (SVR) rates, factors affecting SVR, safety profile, and hepatocellular cancer (HCC) occurrence were analyzed. Results: SVR12 was achieved in 92.8% of the patients (4,040/4,352) according to intention-to-treat and in 98.3% of the patients (4,040/4,108) according to per-protocol analysis. The SVR12 rates were similar between the treatment regimens (97.2%-100%) and genotypes (95.6%-100%). Patients achieving SVR showed a significant decrease in the mean serum alanine transaminase (ALT) levels (50.90 +/- 54.60 U/L to 17.00 +/- 14.50 U/L) and model for end-stage liver disease (MELD) scores (7.51 +/- 4.54 to 7.32 +/- 3.40) (p<0.05). Of the patients, 2 were diagnosed with HCC during the treatment and 14 were diagnosed with HCC 37.0 +/- 16.0 weeks post-treatment. Higher initial MELD score (odds ratio [OR]: 1.92, 95% confidence interval [CI]: 1.22-2.38; p=0.023]), higher hepatitis C virus (HCV) RNA levels (OR: 1.44, 95% CI: 1.31-2.28; p=0.038), and higher serum ALT levels (OR: 1.38, 95% CI: 1.21-1.83; p=0.042) were associated with poor SVR12. The most common adverse events were fatigue (12.6%), pruritis (7.3%), increased serum ALT (4.7%) and bilirubin (3.8%) levels, and anemia (3.1%). Conclusion: LDV/SOF or PrOD +/- RBV were effective and tolerable treatments for patients with CHC and with or without advanced liver disease before and after liver transplantation. Although HCV eradication improves the liver function, there is a risk of developing HCC.Turkish Association for the Study of The Liver (TASL)The present study was supported by The Turkish Association for the Study of The Liver (TASL)

Orta Anadolu’daki Parkinson Hastalarında Homosistein ve MTHFR Polimorfizmleri Arasındaki İlişkinin Araştırılması ve Tedavi Seçenekleri

Aim In this study, we aimed to investigate the effects of MTHFR C677T and A1298C polymorphisms to homocysteine levels in patients with Parkinson's disease who were treated with levodopa and entekapone. Materials and Methods Plasma homocysteine (hcy), folic acid and vitamin B12 levels and MTHFR (C677T, A1298C) polymorphisms and treatment options were compared in 70 Parkinson's Disease (PD) patients who taking levodopa (n=26), dopamine agonist (n=11) and levodopa and entacapone treatment together (n=33) with 100 controls. Results Although no statistically significant difference was detected, hcy level of the patients was found higher compared to control group (patient 18.29 ± 9.22 µmol /l vs control 15.77 ± 7.58 µmol / l) and hcy level was highest in the patients receiving only levodopa (19.56 ± 10.77 µmol / l). The frequency of TT genotype in the patients was higher compared to the control group (11.4%, 6%). Especially, hcy level for levodopa-receiving patients with 677TT genotype became significantly higher level when compared with other genotypes of levodopareceiving patients (respectively 677TT 36.28 ± 16.17, 677CT 13.5 ± 1.71, 677CC 17.2 ± 6.59). No statistically significant difference was detected between patients and controls regarding their folic acid and vitamin B12 levels and A1298C polymorphism. Conclusion Finally, both 677TT genotype and levodopa treatment might be jointly contributed to the increasing of the plasma hcy levels in PD patients and entacapone limitedly decreased hcy levels during levodopa treatment. It can be said that results need to be supported with larger sample sized comprehensive studies.Amaç Çalışmamızda levodopa ve entekapon kullanan Parkinson hastalarında MTHFR genindeki C677T ve A1298C polimorfizmlerinin homosistein düzeyine etkilerini araştırmayı amaçladık. Materyal ve Metot 70 Parkinson (PD) hastasında; plazma homosisteini (hcy), folik asit, B12 vitamini seviyeleri, MTHFR (C677T, A1298C) polimorfizmleri ve tedavi seçenekleri karşılaştırıldı. 100 kişilik bir kontrol grubunun yer aldığı çalışmada, 70 hastanın 26’sı levodopa (n=26), 11’i dopamin agonisti (n=11) kullanırken, 33 hasta da levodopa ve entakapon tedavisini birliktealmaktaydı. Bulgular İstatistiki olarak anlamlı bir fark gözlenmese de, hastalardaki homosistein seviyesinin kontrol grubunda yer alanlara göre daha fazla olduğu tespit edildi (hasta 18.29 ± 9.22 µmol /l vs kontrol 15.77 ± 7.58 µmol/ l). Ayrıca homosistein seviyesinin en yüksek olduğu hasta grubunun sadece levodopa kullanan hastalar olduğu görüldü (19.56 ± 10.77 µmol / l). Hastalardaki TT genotipinin sıklığının da kontrol grubunda yer alanlara göre daha fazla olduğu görüldü (%11.4, %6). Özellikle, levodopa kullanan ve 677TT genotipine sahip olan hastalardaki homosistein seviyesi, levodopa kullanan ve diğer genotiplere sahip olan hastalardaki homosistein seviyesine göre anlamlı bir şekilde yüksek (sırasıyla 677TT 36.28 ± 16.17, 677CT 13.5 ± 1.71, 677CC 17.2 ± 6.59). Hastalar ve kontrol grubu arasında folik asit ve B12 vitamini seviyeleri ile A1298C polimorfizmi açısından anlamlı bir farka rastlanmadı. Sonuç Sonuç olarak; Parkinson hastalarında 677TT genotipinin ve levodopa kullanımının bir arada olmasının plazma homosistein seviyesini artırdığı, ayrıca entakaponun levodopa tedavisi esnasında sınırlı da olsa homosistein seviyesini düşürdüğü gözlemlenmiştir. Ancak sonuçların daha fazla örnek sayısı içeren kapsamlı çalışmalarla desteklenmesinin gerekli olduğu söylenebilir