Blockchain-based Cloud Data Deduplication Scheme with Fair Incentives

With the rapid development of cloud computing, vast amounts of duplicated data are being uploaded to the cloud, wasting storage resources. Deduplication (dedup) is an efficient solution to save storage costs of cloud storage providers (CSPs) by storing only one copy of the uploaded data. However, cloud users do not benefit directly from dedup and may be reluctant to dedup their data. To motivate the cloud users towards dedup, CSPs offer incentives on storage fees. The problems with the existing dedup schemes are that they do not consider: (1) correctness - the incentive offered to a cloud user should be computed correctly without any prejudice. (2) fairness - the cloud user receives the file link and access rights of the uploaded data if and only if the CSP receives the storage fee. Meeting these requirements without a trusted party is non-trivial, and most of the existing dedup schemes do not apply. Another drawback is that most of the existing schemes emphasize incentives to cloud users but failed to provide a reliable incentive mechanism. As public Blockchain networks emulate the properties of trusted parties, in this paper, we propose a new Blockchain-based dedup scheme to meet the above requirements. In our scheme, a smart contract computes the incentives on storage fee, and the fairness rules are encoded into the smart contract for facilitating fair payments between the CSPs and cloud users. We prove the correctness and fairness of the proposed scheme. We also design a new incentive mechanism and show that the scheme is individually rational and incentive compatible. Furthermore, we conduct experiments by implementing the designed smart contract on Ethereum local Blockchain network and list the transactional and financial costs of interacting with the designed smart contract

Bismuth (III) chloride catalyzed efficient and selective cleavage of trityl ethers

A highly selective and efficient protocol has been developed for detritylation using 5 mol% BiCl<SUB>3</SUB> in acetonitrile. The cleavage proceeds at room temperature in high yields and the conditions are mild enough to tolerate a variety of acid-base sensitive functional groups

Preliminary experience with laparoscopic Foley′s YV plasty for ureteropelvic junction obstruction in children

Introduction: Laparoscopic dismembered pyeloplasty is an acceptable option for ureteropelvic junction (UPJ) obstruction in the paediatric population. We compared our results of laparoscopic dismembered and non-dismembered Foley′s YV pyeloplasty. Materials and Methods: Children presenting with hydronephrosis secondary to UPJ obstruction formed the study group. Foley′s YV plasty was planned whenever it was observed that a tension free dismembered pyeloplasty was not possible in spite of all possible manoeuvres. Children were followed up for urinary infection, and renogram was repeated after 3 months. Results: During the study period, 108 children (63 male and 45 female) with a mean age of 4.94 ± 2.78 years underwent laparoscopic dismembered pyeloplasty and the remaining 11 children (5 male and 6 female) with a mean age of 4.00 ± 1.776 years underwent laparoscopic Foley′s YV plasty. There were no major peri-operative complications noted and conversion to open was not necessary in any child. Renogram done at 3 months post-operatively showed good drainage and improvement of renal function. Conclusions: Laparoscopic Foley′s YV pyeloplasty is a safe and effective technique in appropriately selected cases of primary UPJ obstruction in children

Laparoscopic Mitrofanoff continent catheterisable stoma in children with spina bifida

Background: In 1980, Mitrofanoff described the creation of an appendicovesicostomy for continent urinary diversion. This procedure greatly facilitates clean intermittent catheterisation in patients with neurogenic bladder. The purpose of our study was to determine the clinical efficacy of the laparoscopic Mitrofanoff catheterisable stoma for children and adolescents with spina bifida. Materials and Methods: Review of hospital records revealed that 11 children with spina bifida underwent a laparoscopic Mitrofanoff procedure with at least 1-year of follow-up. A four-port transperitoneal laparoscopic approach was used to create a Mitrofanoff appendicovesicostomy. The child was followed-up in the urology clinic at 6 weeks, 3 months, 6 months, 1-year, and then semiannually after that. Questionnaires were administered to determine, from the children′s perspective, the level of satisfaction with catheterisation and the psychosocial implications of catheterisation before and after the creation of the Mitrofanoff continent catheterisable stoma. Results: Of the 11 children, six were female, and five were male. The mean age at presentation to Paediatric urological services was 11 × 3.22 years. Overall the mean operative time was 144.09 × 17.00 min. Mean estimated blood loss was 37.36 × 11.44 cc. None of the cases needed conversion to open. Patient satisfaction with their catheterisation was measured at 2.18 × 0.98 preoperatively, Post-operatively, this improved to 4.27 × 0.46. Statistical analysis using paired t-test showed significance with P < 001. Conclusions: Laparoscopic Mitrofanoff catheterisable stoma is feasible in children with spina bifida and is associated with reasonable outcome with early recovery, resumption of normal activities and excellent cosmesis

Primary ureterocalicostomy in children

Introduction: Ureterocalicostomy involves excision of the hydronephrotic lower renal pole parenchyma and anastomosis of the dismembered ureter directly to the lower pole calyx. Ureterocalicostomy offers distinct advantages over conventional Anderson–Hynes pyeloplasty for the primary surgical management of pelvi-ureteric junction obstruction, notably for obstruction secondary to complicating anatomical anomalies of the kidney, such as horseshoe kidney. The present study was aimed to evaluate the outcome of primary laparoscopic ureterocalicostomy as a primary procedure in children. Materials and Methods: The technique of ureterocalicostomy employed was similar in all children and comprised disconnection of the ureter from the renal pelvis and identification of the most dependent portion of the lower pole calyx by instrumentation within the collecting system. Results: Eight children (five males and three females) underwent primary ureterocalicostomy during the study period. The mean age of the children was 11.37 ± 3.67 years. Five of the eight children underwent laparoscopic ureterocalicostomy, whereas in three, it was necessary to convert to open as the dissection was difficult. The mean operating time was 134 ± 12 min, and the mean blood loss was 48 ± 7.48 cc. Conclusions: Our study shows that primary laparoscopic ureterocalicostomy for ureteropelvic junction obstruction is feasible, safe, and associated with minimal morbidity

1,5-Benzothiazepine Derivatives: Green Synthesis, In Silico and In Vitro Evaluation as Anticancer Agents

Considering the importance of benzothiazepine pharmacophore, an attempt was carried out to synthesize novel 1,5-benzothiazepine derivatives using polyethylene glycol-400 (PEG-400)-mediated pathways. Initially, different chalcones were synthesized and then subjected to a cyclization step with benzothiazepine in the presence of bleaching clay and PEG-400. PEG-400-mediated synthesis resulted in a yield of more than 95% in less than an hour of reaction time. Synthesized compounds 2a–2j were investigated for their in vitro cytotoxic activity. Moreover, the same compounds were subjected to systematic in silico screening for the identification of target proteins such as human adenosine kinase, glycogen synthase kinase-3β, and human mitogen-activated protein kinase 1. The compounds showed promising results in cytotoxicity assays; among the tested compounds, 2c showed the most potent cytotoxic activity in the liver cancer cell line Hep G-2, with an IC50 of 3.29 ± 0.15 µM, whereas the standard drug IC50 was 4.68 ± 0.17 µM. In the prostate cancer cell line DU-145, the compounds displayed IC50 ranges of 15.42 ± 0.16 to 41.34 ± 0.12 µM, while the standard drug had an IC50 of 21.96 ± 0.15 µM. In terms of structural insights, the halogenated phenyl substitution on the second position of benzothiazepine was found to significantly improve the biological activity. This characteristic feature is supported by the binding patterns on the selected target proteins in docking simulations. In this study, 1,5-benzothiazepines have been identified as potential anticancer agents which can be further exploited for the development of more potent derivatives