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Sarwat B Rizvi,1 Lara Yildirimer,1 Shirin Ghaderi,1 Bala Ramesh,1 Alexander M Seifalian,1,2 Mo Keshtgar1,21UCL Centre for Nanotechnology and Regenerative Medicine, Division of Surgery and Interventional Science, University College London, United Kingdom; 2Royal Free Hampstead NHS Trust Hospital, London, United KingdomAbstract: Quantum dots (QDs) are fluorescent semiconductor nanocrystals that have the potential for major advancements in the field of nanomedicine through their unique photophysical properties. They can potentially be used as fluorescent probes for various biomedical imaging applications, including cancer localization, detection of micrometastasis, image guided surgery, and targeted drug delivery. Their main limitation is toxicity, which requires a biologically compatible surface coating to shield the toxic core from the surrounding environment. However, this leads to an increase in QD size that may lead to problems of excretion and systemic sequestration. We describe a one pot synthesis, characterization, and in vitro cytotoxicity of a novel polyhedral oligomeric silsesquioxane (POSS)-coated CdTe-cored QD using mercaptosuccinic acid (MSA) and D-cysteine as stabilizing agents. Characterization was performed using transmission electron microscopy Fourier transform infrared spectroscopy, and photoluminescence studies. POSS-coated QDs demonstrated high colloidal stability and enhanced photostability on high degrees of ultraviolet (UV) excitation compared to QDs coated with MSA and D-cysteine alone (P value < 0.05). In vitro toxicity studies showed that both POSS and MSA-QDs were significantly less toxic than ionized salts of Cd+2 and Te-2. Confocal microscopy confirmed high brightness of POSS-QDs in cells at both 1 and 24 hours, indicating that these QDs are rapidly taken up by cells and remain photostable in a biological environment. We therefore conclude that a POSS coating confers biological compatibility, photostability, and colloidal stability while retaining the small size and unique photophysical properties of the QDs. The amphiphilic nature of the coating allows solubility in aqueous solutions and rapid transfer across cell membranes, enabling the use of lower concentrations of the QDs for an overall reduced toxicity particularly for prolonged live cell and in vivo imaging applications.Keywords: quantum dots, polyhedral oligomeric silsesquioxane, surface coating, cytotoxicity

Background and Objectives: In every disease there are always opportunities for improvement of the individual status, partof which is affected by person's psychological status. Therefore, this study aimed to predict benefit finding in cancer basedon demographic and clinical characteristics, illness cognition, and emotional processing in cancer patients. Materials and Methods: This descriptive study was performed on patients aged 23 to 82 years with cancer in 2020 inSemnan city. The statistical sample consisted of 311 people who were selected by convenience sampling method. Theyresponded to Benefit Finding Scale (BFS), Illness Cognition Questionnaire (ICQ), Emotional Processing Scale (EPS), anddemographic and clinical characteristics questionnaire. Data were analyzed by multiple linear regression analysis using thesimultaneous entry method. Results: The results of correlation test showed that illness cognition, emotional processing, and demographic and clinicalcharacteristics (education, duration of diagnosis, age) had a significant relationship with benefit finding (p<0.05). The resultsof multiple regression showed that a total of 32% of benefit finding changes were explained by predictor variables; out ofwhich variables of illness cognition (β= 0.377, p<0.001), demographic and clinical characteristics (β= -- 0.241, p<0.001), andemotional processing (β= 0.221, p<0.001) had the largest share in explaining the benefit finding in cancer patients,respectively. Conclusion: Due to the existence of benefit finding in cancer patients and its relationship with psychological, demographicand clinical factors, the care givers and treatment team should consider the benefit finding in cancer and the factors affectingit, and in holistic measures, provide effective actions. [ABSTRACT FROM AUTHOR]

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One of the most important factors in a sampling and integrated pest management program is to know the population density and spatial pattern of the insects, especially the invasive ones such as Tuta absoluta (Meyrick) that cause a serious problem in tomato cultivation. Therefore, population density and spatial distribution pattern of T. absoluta was determined in Varamin region (Tehran, Iran) during two growing seasons of 2015 and 2016 on seven tomato cultivars ('Primo Early', 'Rio Grande', 'Cal JN3', 'Petomech', 'Early Urbana Y', 'Super Strain B', and 'Super 2270'). The T. absoluta density was estimated as active mines (with live larvae) and inactive mines (without live larvae) per plant, which, summed together, resulted in the total infestation (total mines per plant). In 2015, the highest mean number of total mines made by T. absoluta was on 'Cal JN3' (21.82 mines plant-1) and the lowest mean was on 'Early Urbana Y' (11.08 mines plant-1). In 2016, the highest and lowest mean population density of T. absoluta was observed on 'Cal JN3' (14.44 larvae plant-1) and 'Super Strain B' (4.60 larvae plant-1), respectively. The spatial distribution pattern of T. absoluta was determined by using Morisita's coefficient, Taylor's power law, and Iwao's patchiness regression method as well as dispersion index of variance-to-mean-ratio. The dispersion index indicated the aggregated pattern of spatial distribution in all tomato cultivars during both years. Taylor's and Iwao's models showed aggregated pattern of distribution on Primo Early' and 'Early Urbana Y', respectively, in 2015 and on 'Super 2270' in 2016. But, on the rest of cultivars, the pattern was determined random. Also, Morisita's coefficient revealed a random distribution pattern for T. absoluta in all of the sampling dates. The smallest optimum sample sizes were estimated with Taylors' coefficients. These results revealed that tomato cultivars affected the population density and spatial distribution pattern of T. absoluta. The coefficients of the spatial pattern can be used for improving the sampling program to estimate the population density of T. absoluta accurately. [ABSTRACT FROM AUTHOR]

The existing relational network Data Envelopment Analysis (DEA) models evaluate the performance of Decision Making Units (DMUs) with precise data. Whereas, in the real-world applications, there are many Supply Chain (SC) networks with imprecise and vague figures. This paper develops a relational network DEA model for evaluating the performance of supply chains with fuzzy numbers. The proposed fuzzy model is capable of evaluating the performance of all kinds of network structures. A pair of twolevel mathematical programs is utilized to convert the fuzzy relational network DEA to a conventional crisp one. For this purpose, the upper and lower bounds of the efficiencies are calculated by ff-cut concept. The proposed model is implemented using actual data from the supply chain of an international shipping company in Iran. [ABSTRACT FROM AUTHOR]

Project portfolio selection is an important problem for having an efficient and effective project management. This paper proposes a new framework to identify the optimal project portfolio. First, the influencing criteria are derived with respect to higher priorities from the fuzzy DEMATEL method under the balanced scorecard framework. Afterwards, a utility-based multi-choice goal programming technique is applied to determine the project portfolio in regard to the chosen criteria and some other operational limitations. The synergy amongst projects and the outsourcing option are also taken into account in order to provide a more realistic selection process. Finally, applicability and validity of the proposed integrated model are tested by a case study conducted in a pharmaceutical company. [ABSTRACT FROM AUTHOR]