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The fracture strengths and elastic moduli of arc-grown multi-walled carbon nanotubes (MWCNTs) were measured by tensile loading inside of a scanning electron microscope (SEM). Eighteen tensile tests were performed on 14 MWCNTs with three of them being tested multiple times (3Â, 2Â, and 2Â, respectively). All the MWCNTs fractured in the Bsword-insheath'' mode. The diameters of the MWCNTs were measured in a transmission electron microscope (TEM), and the outer diameter with an assumed 0.34 nm shell thickness was used to convert measured loaddisplacement data to stress and strain values. An unusual yielding before fracture was observed in two tensile loading experiments. The 18 outer shell fracture strength values ranged from 10 to 66 GPa, and the 18 Young's modulus values, obtained from a linear fit of the stress-strain data, ranged from 620 to 1,200 GPa, with a mean of 940 GPa. The possible influence of stress concentration at the clamps is discussed.

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Cutaneous Malignant Melanoma (CMM) incidence has been rising around the world and over the last three decades at rates greater than for any other malignancy. Our objective was to describe geographic trends in incidence and mortality of CMM in Russia between 2001 and 2017 using geo-informatics technique (mapping) and descriptive statistical analysis. Additionally, we aimed to study the associations between ethnicity, geographic latitude/longitude and CMM incidence/mortality rates. We retrospectively analyzed the data from the Moscow Oncology Research Institute, Ministry of Health of Russian Federation for the period of the study. International Classification of Diseases (ICD) C43 code (comprising C43.0-C.43.9) was used to identify cutaneous melanoma cases. Routine methods of descriptive epidemiology were used to study incidence and mortality rates by age groups, years, and jurisdictions (i.e., Federal Districts and Federal Subjects of Russia). In total 141,597 patients were diagnosed with melanoma in Russia over the period 2001-2017, of which 62% were women (p<0.001). The overall age-standardized incidence and mortality rates were 4.27/100,000 and 1.62/ 100,000, respectively. Geographic mapping revealed North-to-South and East-to-West gradients across the country. Intrinsic patient characteristics such as the skin phenotype and the climate zones of the country could be an important risk factors for melanoma development. This study, for the first time, reports the burden and geographic distribution of CMM in Russia and the trends correlate with observations in countries with similar geography.

Human papilloma virus plays a causal role in cervical carcinogenesis. However, only a small portion of infected individuals develop cervical cancer. Host genetic factors may confer susceptibility to this disease. CD28 participates in the maintenance of immune homeostasis as an important positive co-stimulatory molecule. Allelic variation of immuno-modulatory genes may be associated with alteration in immune function. This study investigated the associations between CD28 IVS3 +17T>C polymorphism and risk of cervical cancer in the Chinese population. Genotypes of CD28 polymorphism were detected in 619 cases with primary cervical cancer and in 985 normal controls. The odds ratios (ORs) and 95% confidence intervals (CIs) were calculated by unconditional logistic regression. A higher frequency of CD28 +17TC heterozygote was determined in patients in comparison with controls (19.4% versus 12.5%). Subjects carrying at least one CD28 IVS3 +17 C allele (TC or CC genotype) had increased risk of cervical cancer (OR=1.66, 95% CI=1.27-2.17). This study suggests that the CD28 IVS3 +17T>C polymorphism might be genetic susceptibility factor for cervical cancer in Chinese population.

SummaryNanostructures, such as nanowires, nanotubes and nanocoils, can be described in many cases as quasi one-dimensional curved objects projecting in three-dimensional space. A parallax method to construct the correct three-dimensional geometry of such onedimensional nanostructures is presented. A series of scanning electron microscope images was acquired at different view angles, thus providing a set of image pairs that were used to generate three-dimensional representations using a matlab program. An error analysis as a function of the view angle between the two images is presented and discussed. As an example application, the importance of knowing the true three-dimensional shape of boron nanowires is demonstrated; without the nanowire's correct length and diameter, mechanical resonance data cannot provide an accurate estimate of Young's modulus.

Purpose/Objective(s): Severe oral mucositis (SOM, assessed WHO grade 3 or 4) occurs in up to 70% of patients receiving CRT for OSCC, many of whom require enteral nutrition or experience treatment interruption. Pharmacological targeting of nuclear factor erythroid related factor (Nrf2) represents an opportunity to mitigate radiation-associated toxicities mediated by oxidative species (OS). Preclinical studies demonstrate R001 activates Nrf2, a key regulator of gene expression encoding antioxidant, phase II detoxifying enzymes, and downstream Antioxidant Response Element signaling pathways. Activation of Nrf2 increases the threshold and buffering capacity of OS generated by CRT, and its multi-target activity provides a counterbalance to oxidative stress resulting in focal and systemic radioprotection. This proof of concept Phase 2a randomized clinical trial examined the safety, efficacy and schedule-dependent effects of R001 in reducing the incidence, severity and duration of SOM. Materials/Methods: Patients with OSCC treated with definitive or postoperative CRT were randomized to one of 4 treatment arms: 2 doses/week for 2 weeks before (pre) CRT (Arm 1); pre-CRT plus 2 doses or pre-CRT plus 6 weekly doses during CRT (Arm 2, 3 respectively); or standard of care (SOC) (Arm 4). The primary endpoint was duration of SOM through resolution < grade 2. Secondary endpoints included safety, time to onset, incidence, and duration of SOM and grade 4 mucositis through 60 and 70 Gy. Results: Between June 2018 and July 2019 across 11 institutions, 53 patients were randomized, with 45 evaluable. Short 15-minute infusions of R001 were well tolerated with no associated serious adverse events (SAE). Side effects were comparable to SOC. Trends in treatment benefits for all endpoints were consistent across the 3 treatment arms, with the greatest effect size in Arm 1. R001 delayed time to onset (38 vs. 26 days) and duration of SOM (22 vs. 40 days), with 83% having resolution vs 60% with SOC, respectively. No patients developed grade 4 mucositis vs 30% SOC arm. A 95% decrease in duration of SOM (1 vs 17 days) through 60 Gy was also observed. Gastrostomy requirement was reduced by 45% (33% vs 60%). Conclusion: In this small open-label trial, R001 demonstrated a favorable benefit-risk profile with a markedly decreased incidence and duration of SOM through 60 Gy, 70 Gy and follow-up post CRT. Treatment effect was greatest in Arm 1 suggesting short periods of Nrf2 activation prior to generation of OS by CRT may be sufficient to increase the threshold and buffering capacity of antioxidants. Larger, blinded trials, confirming the observed dose, schedule and treatment effect are planned.

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