Improvement of stability and speed in liquid-environment atomic force microscopy

13301甲第4232号博士（工学）金沢大学博士論文要旨Abstract 要約Outline 以下に掲載：1.Review of Scientific Instruments 85(12) pp.126106-126106-3 2014. American Institute of Physics. 共著者：S M R Akrami, K. Miyata, H. Asakawa, T. Fukuma 2.Nanotechnology 25(45) pp.455701-1-455701-8 2014. Institute of Physics. 共著者：S M R Akrami, H. Nakayachi, T. Watanabe-nakayama, H. Asakawa, T. Fukuma 3.Jpn. J. Appl. Phys. 2015. Institute of Physics. 共著者：K. Miyata, K. Miyata, S M R Akrami, T. Fukum

Note: High-speed Z tip scanner with screw cantilever holding mechanism for atomic-resolution atomic force microscopy in liquid

High-speed atomic force microscopy has attracted much attention due to its unique capability of visualizing nanoscale dynamic processes at a solid/liquid interface. However, its usability and resolution have yet to be improved. As one of the solutions for this issue, here we present a design of a high-speed Z-tip scanner with screw holding mechanism. We perform detailed comparison between designs with different actuator size and screw arrangement by finite element analysis. Based on the design giving the best performance, we have developed a Z tip scanner and measured its performance. The measured frequency response of the scanner shows a flat response up to ∼10 kHz. This high frequency response allows us to achieve wideband tip-sample distance regulation. We demonstrate the applicability of the scanner to high-speed atomic-resolution imaging by visualizing atomic-scale calcite crystal dissolution process in water at 2 s/frame

Improvements in fundamental performance of liquid-environment atomic force microscopy with true atomic resolution

Recently, there have been significant advancements in liquid-environment atomic force microscopy (AFM) with true atomic resolution. The technical advancements are followed by a rapid expansion of its application area. Examples include subnanometer-scale imaging of biological systems and three-dimensional measurements of water distributions (i.e., hydration structures) and fluctuating surface structures. However, to continue this progress, we should improve the fundamental performance of liquid-environment dynamic-mode AFM. The present AFM technique does not allow real-time imaging of atomic-scale dynamic phenomena at a solid-liquid interface. This has hindered atomic-level understanding of crystal growth and dissolution, catalytic reactions and metal corrosion processes. Improvement in force sensitivity is required not only for such a high-speed imaging but also for various surface property measurements using a high-resolution AFM technique. In this review, we summarize recent works on the improvements in the force sensitivity and operation speed of atomic-resolution dynamic-mode AFM for liquid-environment applications. © 2015 The Japan Society of Applied Physics.Embargo Period 12 month

COVID‑19 associated rhino‑orbito‑cerebral mucormycosis, risk factors and outcome predictors; a multicentric study

Background Since the onset of the Covid-19 pandemic, an increase in mucormycosis cases has been observed in many countries, including Iran. However, the role of covid-19 and associated risk factors have not been thoroughly investigated. Objective This study is designed to identify epidemiologic characteristics, risk factors, and outcome predictors of Covid-19-Associated Rhino-Orbito-Cerebral Mucormycosis (C-ROCM). Methods Data of pathology proven Covid Associated ROCM cases were retrospectively obtained from 7 tertiary care centers throughout Iran from February 20, 2021, to July 22, 2021. Univariate and multivariate analyses were performed using binary logistic regression to assess the effects of various factors on the outcome. Results A total of 132 patients with C-ROCM were included in the study. The mean age of patients was 61.6 ± 13.9 (60.6% male). In 12 patients (9.1%), both eyes were involved. Diabetes was the mostcommon comorbidity (94.7%). The mortality rate was 9.1%, higher in males (12.5%) than females (3.8%). Severe vision impairment was seen in 58 patients (43.9%). Main factors that had a negative impact on the outcome in the univariate analysis include older age (P < 0.001), higher steroid dosage (P < 0.001), higher HbA1c level (P < 0.001), Covid-19 severity (P < 0.001), and brain involvement (P < 0.001). However, in the multivariate analysis, the effects of age (P = 0.062), steroid dosage (P = 0.226), and Covid- 19 intensity (P = 0.084) decreased, and the difference was no longer statistically significant. CRAO was a predictor of mortality in the univariate analysis (P = 0.008, OR = 4.50), but in the multivariate analysis, this effect decreased and was no longer significant (P = 0.125). Conclusion The risk of C-ROCM and its complications may increase in patients with more severe Covid-19, steroid over-prescription, ICU admission due to Covid-19, and poor glycemic control during and after Covid-19 treatment

Diagnostic application of human DNA copy number analysis

Available from British Library Document Supply Centre- DSC:DXN058018 / BLDSC - British Library Document Supply CentreSIGLEGBUnited Kingdo

Mitochondrial Variants in Pompe Disease: A Comparison between Classic and Non-classic Forms

Objective Pompe disease (PD) is a progressive neuromuscular disorder that is caused by glucosidase acid alpha (GAA) deleterious mutations. Mitochondrial involvement is an important contributor to neuromuscular diseases. In this study the sequence of MT-ATP 6/8 and Cytochrome C oxidase I/II genes along with the expression levels of the former genes were compared in classic and non-classic patients. Materials and Methods In this case-control study, the sequence of MT-ATP 6/8 and Cytochrome C oxidase was analyzed by polymerase chain reaction (PCR)-Sanger sequencing and expression of MT-ATP genes were quantified by real time-PCR (RT-PCR) in 28 Pompe patients. The results were then compared with 100 controls. All sequences were compared with the revised Cambridge reference sequence as reference. Results Screening of MT-ATP6/8 resulted in the identification of three novel variants, namely T9117A, A8456C and A8524C. There was a significant decrease in MT-ATP6 expression between classic (i.e. adult) and control groups (P=0.030). Additionally, the MT-ATP8 expression was significantly decreased in classic (P=0.004) and non-classic (i.e. infant) patients (P=0.013). In total, 22 variants were observed in Cytochrome C oxidase, five of which were non- synonymous, one leading to a stop codon and another (C9227G) being a novel heteroplasmic variant. The A8302G in the lysine tRNA gene was found in two brothers in a pedigree, while a T7572C variant in the aspartate tRNA gene was observed in two brothers in another pedigree. Conclusion The extent of mitochondrial involvement in the classic group was more significant than in the non-classic form. Beside GAA deleterious mutations, it seems that mtDNA variants have a secondary effect on PD. Understanding, the role of mitochondria in the pathogenesis of Pompe may potentially be helpful in developing new therapeutic strategies