Determination of caffeine in roasted and irradiated coffee beans with gamma rays by high performance liquid chromatography

The present study was carried out to investigate a simple, quick and organic solvent saving procedure for the high performance liquid chromatography determination of caffeine in two different coffee beans (Indonesian and Brazilian) which roasted at two different temperatures (150 & 220 ºC) and irradiated at 3, 6, and 9 kGy doses by gamma rays. A linear calibration curve was generated with caffeine concentration ranging from 0.005 to 0.25 mg/g with correlation coefficient (R2= 0.9995, n=4) and relative standard deviation ? 2.1 %. The developed procedure provided a 7.3 x 10-9 mg/g and 2.2 x 10-8 mg/g limit of detection and limit of quantification, respectively. The developed method was repeatable and could be applied to determine trace amounts of caffeine in popular irradiated coffee beans with three different irradiation doses. Moreover, irradiation treatments at doses up to 9 kGy showed no significant effect on the caffeine content. Keywords: Caffeine determination; High performance liquid chromatography;  Coffee bean; Roasting; Gamma rays; Statistical analysi

Implementation of rock typing on waterflooding process during secondary recovery in oil reservoirs : a case study, El Morgan oil field, Gulf of Suez, Egypt

Waterflooding is one of the most common secondary recovery methods in the oil and gas industry. Globally, this process sometimes suffers a technical failure and inefficiency. Therefore, a better understanding of geology, reservoir characteristics, rock typing and discrimination, hydraulic flow units, and production data is essential to analyze reasons and mechanisms of water injection failure in the injection wells. Water injection failure was reported in the Middle Miocene Hammam Faraun reservoir at El Morgan oil field in the Gulf of Suez, where two wells have been selected as injector’s wells. In the first well (A1), the efficiency of injection was not good, whereas in the other analog A2 well good efficiency was assigned. Therefore, it is required to assess the injection loss in the low efficiency well, where all aspects of the geological, reservoir and production data of the studied wells were integrated to get a complete vision for the reasons of injection failure. The available data include core analysis data (vertical and horizontal permeabilities, helium porosity, bulk density, and water and oil saturations), petrographical studies injection and reservoir water chemistry, reservoir geology, production, and injection history. The quality of the data was examined and a set of reliable X–Y plots between the available data were introduced and the reservoir quality in both wells was estimated using reservoir quality index, normalized porosity index, and flow zone indicator. Integration and processing of the core and reservoir engineering data indicate that heterogeneity of the studied sequence was the main reason for the waterflooding inefficiency at the El Morgan A1 well. The best reservoir quality was assigned to the topmost part of the reservoir, which caused disturbance of the flow regime of reservoir fluids. Therefore, it is clearly indicated that rock typing and inadequate injection perforation strategy that has not been aligned with accurate hydraulic flow units are the key control parameters in the waterflooding efficiency

Paclitaxel resistance in breast cancer: Current challenges and recent advanced therapeutic strategies

Breast cancer (BC) is one of the leading causes of cancer-related deaths among women worldwide. Paclitaxel (PTX), a chemotherapeutic agent derived from the taxane family, is commonly used in treating BC due to its ability to disrupt microtubule dynamics and induce cell death. However, resistance to PTX presents a significant challenge, as it diminishes the drug's effectiveness and can lead to treatment failure. This review explores the mechanisms by which PTX exerts its effects and the various factors contributing to resistance. These factors include genetic mutations that affect tubulin dynamics, the role of non-coding RNAs, molecular pathways involved in chemoresistance, epigenetic changes, post-transcriptional modifications, increased activity of ABC transporters that promote drug efflux, immunosuppressive interactions within the tumor microenvironment, and resistance mediated by autophagy. This review also explores strategies to overcome PTX resistance, including molecular and genetic innovations, combination therapies, and nanotechnology-based approaches. These strategies may improve PTX efficacy and enhance treatment outcomes for BC patients.</p

Bronchoscopic Advances in the Management of Aerodigestive Fistulas

Malignant aerodigestive fistula (ADF) is an uncommon condition complicating thoracic malignancies. It results in increased morbidity and mortality and warrants therapeutic intervention. The management approach depends on symptoms, configuration, location, and extent of the fistula. This article will discuss the therapeutic considerations in the management of ADF

Performance Improvements of a Permanent Magnet Synchronous Machine via Functional Model Predictive Control

This paper investigates the application of the model predictive control (MPC) approach to control the speed of a permanent magnet synchronous motor (PMSM) drive system. The MPC is used to calculate the optimal control actions including system constraints. To alleviate computational effort and to reduce numerical problems, particularly in large prediction horizon, an exponentially weighted functional model predictive control (FMPC) is employed. In order to validate the effectiveness of the proposed FMPC scheme, the performance of the proposed controller is compared with a classical PI controller through simulation studies. Obtained results show that accurate tracking performance of the PMSM has been achieved

A modified approach for solving a fuzzy multi-objective programming problem

Abstract Based on ranking of fuzzy numbers which deals with fuzzy-valued multi-objective programming problem and the modified crisp model, a modified approach is proposed. Also, two algorithms that play a pivotal role in the proposed method are introduced. The first one returns a ranking function to a given fuzzy number and the second algorithm uses the modified crisp model to deliver a Pareto optimal solution. Moreover, we investigate the stability of the first kind of the solution which is obtained using these algorithms. Finally, a numerical example is given to illustrate our modified approach, using Maple program

Structural, Optical and Single-domain Magnetic Features of the Noncollinear Ferrimagnetic Nano-spinel Chromites ACr2_2O4_4 (A = Ni, Co, and Mn)

Spinel chromites ACr$_2$O$_4$ with inherent magnetic geometrical frustration usually exhibit a noncollinear ferrimagnetic ground state when A are magnetic ions, with possibly crystallite-size dependent intriguing magnetic features. Here, we report single-domain magnetic properties of ACr$_2$O$_4$ (A = Ni, Co, and Mn) nanocrystals, with an average crystallite size of 18, 15 and 10 nm, exhibiting an optical energy gap of 2.87, 3.05 and 2.9 eV, respectively. The temperature dependence of magnetization indicates the main bulk magnetic transitions with a commonly coexisting spin-glass-like state and finite-size effects on the noncolinear ferrimagnetic transitions. An anomaly observed at Ts = 15, 24 and 10 K is attributed to the bulk magnetic transition to a canted antiferromagnetic state in NiCr$_2$O$_4$ and incommensurate spiral orders in CoCr$_2$O$_4$ and MnCr$_2$O$_4$ NCs, respectively. A further bulk magnetic transition to a commensurate spiral order is observed for CoCr$_2$O$_4$ NCs at a lock-in temperature Tl = 5 K much lower than that reported using bulk samples, while it is completely suppressed in the MnCr$_2$O$_4$ NCs. Finite-size effects and single-domain magnetic behaviors indicated by anomalous temperature-dependences of the coercive field and the hysteresis-loop squareness, mainly driven by a magnetocrystalline anisotropy, are discussed in comparison to results reported using bulk counterparts

Identifying leaf rust resistance gene Lr19 in durum wheat using simple sequence repeat (SSR) marker

Leaf rust, caused by Puccinia triticina Eriks., is an important disease affecting durum wheat (Triticum turgidum ssp. durum) worldwide, particularly in the Mediterranean region. The disease can be controlled through the use of plant host resistance. Based on seedling resistance tests of 103 durum genotypes against a bulk of P. triticina, urediniospores were previously collected from Syria and Lebanon during 2007/08 and 2008/09 growing seasons. Percentage of resistance in the durum set tested was up to 52%. The resistant genotypes might have one of the following resistance gene(s): Lr15, Lr 19, Lr 24, Lr 25, Lr 27 +31, Lr 28 and Lr 29. Results revealed that the Gb/130-bp polymorphic band was linked to Lr19 and Sr25. In this study, twelve genotypes carrying resistance to Lr19 and Sr25 have been identified (Azeghar2, Rutucha1, Ammar9/Azeghar2, Ammar9/Terbol97-4, T.polonicum9/Ch1//Icamor-TA04-68/3/Icamor-TA04-69//(Lahn/ Ch1)2519, Arislahn5//Icamor-TA04- 63/Icasyr1, T.dicoccum1/Ch1//Ammar8/3/Bonadur/Icamor-TA04-63, Mrb3/ T. urartu500651/4/Icamor- TA04-63/3/Bcr/Gro1// Mgnl1, SwAlg/Gd1-81 //Ch1-48, Icamor-TA04-1//Mgnl3/Ainzen1, 319-ADDO/5/D68-1- 93A-1A//Ruff/Fg/3/Mtl5/4/Lahn, and Mrf1/Stj2/3/1718/BT24//Karim). Promising results on Gb/130-bp and genotypes carrying Lr19 and Sr25 will be used in a marker assisted selection of the durum breeding programs in the Mediterranean region.Key words: Puccinia triticina, durum genotypes, Syria, Lebanon, Lr19, Sr25, Gb primer