Exploitation of macrocyclic chemical space by multicomponent reaction (MCR) and their applications in medicinal chemistry

Het onderzoek beschreven in het promotieonderzoek van Eman Mahmoud Mohammed Abdelraheem is gericht op de ontwikkeling van nieuwe synthetische technologie die toegang verschaffen tot kunstmatige macrocycles met potentiele biologische activiteit. kunstmatige macrocycles zijn een steeds meer voorkomende en grotendeels onderbenutte gedeelte van de chemische ruimte die de potentie biedt voor de ontdekking van moeilijke post-genomic targets. De huidige farmaceutische bibliotheken zijn grotendeels ongeschikt om de grote hoeveelheid aan interessante genetische doelen te behalen, terwijl kunstmatige macrocycles de bestaande kloof tussen kleine moleculen en grote biologische moleculaire gewichten kunnen verkleinen. Alhoewel kunstmatige macrocycles veel voordelen bieden ten opzichte van hun natuurlijke tweelingstructuur, zoals betere controle over de syntheseroute, de ADMET eigenschappen en het binden aan het doelwit, zijn snelle en convergerende syntheserouten onderontwikkeld. De multi-component reactie (MCR) is een veelbelovende, snelle, en simpele synthese methodologie die toegang bied tot een hoge diversiteit voor de synthese van een grote diversiteit aan macrocyclische componenten. MCRs zijn in staat een grote hoeveelheid aan moleculaire diversiteit te genereren voor complexe macrocyclische structuren tegen lage synthese kosten. Ook, het ontwerp en evaluatie van nieuwe p53-MDM2/X inhibitoren zijn gepresenteerd

Effect of Changing Properties of Wythes in Precast Structural Sandwich Panels

This study investigates the effects of changing in the properties of face and core wythes in structural sandwich panels (with dimensions of 500 500 mm and 120 mm total height). Concrete face wythes of three grades (80, 70, 37) MPa, thicknesses of (25, 35, and 45) mm, and three types of core materials (high density foam, polyethylene foam, and palm bark) were used in the production of panels. Steel shear connectors were installed in the panels with angle of 45º. Three-point bending load test was carried out on all panels and results were compared with both of the theoretical extremes capacities of non- composite and fully-composite states and ANSYS software results. The degree of composite action (%) and the (strength/weight) ratio were the main parameters that judged the specimens. It was found that upgrading concrete increased overall strength of slabs especially in high strength concrete (80 MPa), however the use of lightweight concrete (70 MPa) caused high (strength/weight) ratio due to very lightweight. Results revealed that decreasing thickness of concrete face wythes had a positive effect on strength/weight ratio (although the ultimate loads decreased) that enhanced the performance of panels as lightweight structural panels. The optimum face wythe thickness is that of 2.5 cm and has high (strength/weight) ratio. It was noticed that adding polyethylene foam as a core material results in positive effect and high (strength/weight) ratio. Results revealed that high strength concrete (80 MPa) and light-weight concrete (37 MPa) are very successful in the production face wythes of precast light-weight sandwich panels that can obtain high (strength/weight) ratio and high percent of composite action

Transabdominal pre-peritoneal (TAPP) versus totally extraperitoneal (TEP) laparoscopic techniques for inguinal hernia repair

Background: Hernia repair is one of the most frequently performed surgeries worldwide. Surgical treatment is usually successful in the majority of cases. However, a recurrence rate of 10% is reported irrespective of the surgical approach. Postoperative pain and disability are frequent. Laparoscopic repair has largely replaced open surgery in the treatment of inguinal hernia. Objectives: To evaluate TAPP and TEP laparoscopic techniques for treatment of inguinal hernia repair regarding safety and outcome. Patients and methods: This prospective randomized clinical trial study was carried out on 40 patients with inguinal hernia who underwent laparoscopic repair. Patients were distributed into 2 groups, group A patients had transabdominal preperitoneal (TAPP) repair while group B patients underwent totally extraperitoneal (TEP) repair. Both groups were evaluated according to occurrence of intraoperative complications, operative time, bleeding amount, hospital stay, postoperative pain (visual analogue scale) and duration for return of bowel movements. Results: There was no statistically significant difference between both groups in each studied parameter. However, there was significantly less postoperative pain in TAPP group (p-value= 0.008) and TEP group (p-value= 0.001). Conclusion: In conclusion, both TAPP and TEP achieved similar results in the parameters evaluated during this study. Both approaches can be used in the treatment of inguinal hernia repair

Childhood Steroid Sensitive Nephrotic Syndrome: Characteristics and Predictors of Relapses; A study at a Single Center in Khartoum

Background: Childhood steroid-sensitive nephrotic syndrome (SSNS) usually has a favorable outcome in spite of its relapsing course. The objective of the authors was to study the demographic and clinical characteristics, outcome and risk factors for relapses in children with SSNS at a single center in Khartoum, Sudan. Material and Methods: In this cross-sectional, facility-based study, the authors retrospectively reviewed all the records of children with SSNS, followed at the Pediatric Renal Unit, Soba University Hospital, Khartoum between 2001 and 2014. SSRNS was defined as the remission of proteinuria within 4–6 weeks of corticosteroids. Relapse is therecurrence of proteinuria after remission; frequent if ≥ 2 within initial six months or ≥ 4 within one year, and steroid dependence if 2 during therapy or within 14 days after stopping it. Results: 330 children (males 220; 66.7%) with SSNS were studied with a mean age of 5.2 ± 3.5 years of whom 42.4% aged 1–5 years. At the presentation, hypertension was detected in 31.8% and hematuria in 19.1%. Serum cholesterol was elevated in all patients (mean 347.34 ± 117.87 mg/dl) and serum creatinine in 7.27% (mean 1.4 ± 0.35 mg/dl). Renal histology showed mesangioproliferative glomerulonephritis (MesPGN) in 57.5%, minimal change disease (MCD) in 35.5%, and focal segmental glomerulosclerosis (FSGS) and IgM nephropathy in 3.5% each. During the course of the illness, 10.3% achieved long-term remission, 89.7% relapsed— of whom 52.3% had frequent relapsing/steroid-dependent (FR/SD) course and 37.7% had infrequent relapses. Risk of frequent relapses were age of onset and low/moderate socioeconomic status (P = 0.015 and 0.019, respectively). Infectionswere recorded in 71.8%, but not significantly associated with the risk of frequent relapses (P > 0.05). Conclusions: The majority children with SSNS at this single center in Khartoum had a relapsing course with the majority being FR or SD. Predictors of frequent relapses were young age at onset and low socioeconomic status

Weak-Key Analysis of POET

We evaluate the security of the recently proposed authenticated encryption scheme POET with regard to weak keys when its universal hash functions are instantiated with finite field multiplications. We give explicit constructions for weak key classes not covered by POET\u27s weak key testing strategy, and demonstrate how to leverage them to obtain universal forgeries

Cryptanalysis of ARMADILLO2

Abstract. ARMADILLO2 is the recommended variant of a multi-purpose cryptographic primitive dedicated to hardware which has been proposed by Badel et al. in [1]. In this paper, we describe a meet-in-themiddle technique relying on the parallel matching algorithm that allows us to invert the ARMADILLO2 function. This makes it possible to perform a key recovery attack when used as a FIL-MAC. A variant of this attack can also be applied to the stream cipher derived from the PRNG mode. Finally we propose a (second) preimage attack when used as a hash function. We have validated our attacks by implementing cryptanalysis on scaled variants. The experimental results match the theoretical complexities. In addition to these attacks, we present a generalization of the parallel matching algorithm, which can be applied in a broader context than attacking ARMADILLO2

Properties of High-Performance Concretes made of Black Sand at High Temperature

To modify high-performance concrete (HPC) fireproofing properties, black sand (BS) was partially substituted as fine aggregate at various levels. This study aims at evaluating the BS reliability in improving HPC durability properties for various construction applications based on its unique heavy minerals. To achieve this, five HPC series blends were setup to substitute fine aggregate independently with BS. Substitution percentages ranged from 15 to 100% with consistent supplementary cementing materials (SCMs) proportion for each gathering. Tests were performed to assess compressive strength before and after fire exposure under various temperatures of 250, 500 and 750 °C at different curing age. Generally, blending FA with BS was better than using SF with BS. Utilizing BS in the range of 15 to 60% as fine aggregate with 10% FA improves HPC fire-insulating properties. Besides, Z1 SEM analysis observed homogenously and compacted HPC microstructure at 250 and 500 °C. Doi: 10.28991/cej-2021-03091634 Full Text: PD

Effect of An Educational Intervention About Occupational Safety on Knowledge and Practices of Male Students in Technical Mechanical Secondary Schools in El-Behira Governorate

Background. Occupational health and safety is one of the most important aspects of human concern. The Aim of this study is to evaluate the effect of educational intervention about occupational safety on knowledge and practice of male students in technical mechanical secondary schools in El-Behira governorate. Hypothesis: Technical Mechanical secondary school male students who engage in occupational safety intervention will demonstrate higher level of knowledge and practice than those who are not . Material and Methods: Quasi-experimental pre/post–test research design. Settings: the study was conducted in four technical mechanical secondary schools in El-Behira governorate. Subjects: the study was carried on 280 students (140 were cases and 140 were control).Data collection tools: data were collected using three tools: structured self-administered questionnaire, Students' knowledge regarding occupational safety and observation check list regarding safety measures practices in the training workshops.Results: conveyed that less than half (46.4%, 47.9%) of both the study and the control group respectively were aged between   16 to less than 17 years. All the study group and the control one had poor knowledge regarding occupational health and safety before conduction of the educational intervention, whereas after implementation of the educational intervention, more than three quarters of the study group (85.7%) had good knowledge whereas the vast majority of the control group (99.3%) still had poor knowledge  . There was a statistically significant relation between the department and the total knowledge score of the study group (X2= 14.150 , P=0.007*).Conclusion: The educational program is successful in attaining its aim of positively improving knowledge, and practice of the study group   about Occupational Health and Safety.Recommendations: this study recommend the necessity of provision of personal protective equipment to the students in the school workshops and integrating occupational safety topics in their curriculum. Keywords: Educational intervention, occupational health, Knowledge, Technical secondary schools. DOI: 10.7176/JHMN/80-05 Publication date:September 30th 202