Sustainable Stabilization of Poorly Graded Desert Sand by Cement Kiln Dust and Salt Water for Using in Backfilling and Subbase Layers

Effective use of natural materials and industrial by products has a direct impact on economy, sustainable environment, and waste management. Poorly graded desert sand (SP) is widely observed in sand dunes and sand seas. Studies were performed to get beneficial use of cement kiln dust (CKD) in soil improvement. But there is a lack of information concerning using of CKD as an improving material for poorly graded sand with the aid of salt water. Salt water is widely available in Egypt from seas and some deep wells, using it will help in saving drink water which suffers from shortage in many countries. The aim of this research is to study the possibility of improving SP using CKD and salt water to be used in backfilling work and subbase layers of roads and pavements. Mixtures of poorly graded sand and various CKD ratios (10%, 20% and 30%) were classified and tested using grain size distribution, compaction, shear strength and California bearing tests. The results were compared with potable water. The results show that adding CKD improves the characteristic properties of SP even with salt water. The study enhances the using of 20% CKD with optimum water content of 9.12% of salt water to have noticeable improvement for SP and to be used efficiently in backfilling and subbase layers

OPTIMIZIRANJE GUSTOĆE PRAŠINE IZ PEĆI ZA DOBIVANJE CEMENTA S CILJEM POBOLJŠANJA ISKORIŠTENJA PROSTORA NA ODLAGALIŠTU

Optimizing the density of waste materials in landfills by proper compaction prolongs the facility life due to the efficient use of landfill airspace. Cement kiln dust (CKD) is a waste by-product produced in huge amounts which exceeds the used quantities in the cement recycling industry and beneficial CKD applications. The vast amount of CKD is almost landfilled in its loose state in Egypt which causes a big loss in landfill airspace due to the low density of CKD. The hydraulic binder effect and dusty behavior of reactive CKD complicates its compaction process. Accordingly, this research was performed to investigate CKD compaction properties with three types of lubricants, which are potable water, salt water and waste oil. Maximum dry density (MDD) and optimum moisture content (OMC) for these lubricant types and different wetting methods were investigated in order to improve the landfill air space utilization and to reduce the dusty effect of CKD during compaction. The effect of immediate compaction after wetting and the effect of compaction delay by allowing CKD to hydrate initially for a certain period were studied. Compaction energy and methods of the wetting of CKD either by full submergence in water or prewetting were tested. The maximum weights of a disposed CKD and durations required to fill an intended landfill air space for different CKD conditions, lubricant types and compaction methods were presented for a case study in Ain Sokhna, Egypt.Optimiziranje gustoće otpadnih materijala na odlagalištima pravilnim zbijanjem produljuje vijek trajanja objekta zahvaljujući učinkovitom korištenju odlagališnog prostora. Prašina iz peći za dobivanje cementa (PDC) je otpadni nusproizvod koji nastaje u velikim količinama koje znatno premašuju količine materijala koji se može reciklirati u cementnoj industriji i korisno upotrijebiti na druge načine. Velika količina PDC-a u Egiptu se odlaže na odlagališta u rastresitom stanju, što uzrokuje veliki gubitak odlagališnog prostora zbog niske gustoće PDC-a. Učinak hidrauličkog veziva i ponašanje reaktivnog PDC-a kao prašinastog materijala komplicira proces njegovog zbijanja. U skladu s tim, ovo je istraživanje provedeno kako bi se ispitala svojstva zbijanja PDC-a s tri vrste ovlaživača/lubrikanata pitka voda, slana voda i otpadno ulje. Maksimalna suha gustoća i optimalni sadržaj vlage ispitani su za te vrste ovlaživača/lubrikanata i za različite metode vlaženja kako bi se poboljšala iskorištenost odlagališnog prostora i smanjio negativni učinak PDC-a tijekom zbijanja. Proučavani su učinak neposrednog zbijanja nakon vlaženja i učinak odgode zbijanja dopuštanjem PDC-u da se inicijalno hidratizira tijekom određenog razdoblja, a zatim odradi zbijanje. Ispitana je energija zbijanja i metode vlaženja PDC-a potpunim uranjanjem u fluid ili prethodnim vlaženjem. Prezentirane su maksimalne težine odloženog PDC-a i vrijeme potrebno za ispunjavanje predviđenog odlagališnog prostora za različite PDC uvjete, vrste ovlaživača/lubrikanata i metode zbijanja za studiju slučaja Ain Sokhna u Egiptu

Modulatory role of chelating agents in diet-induced hypercholesterolemia in rats

AbstractIntroductionHypercholesterolemia is a major risk factor for the development of atherosclerosis and endothelial dysfunction. Chelating agents may play a modulatory role in atherosclerosis by removal of calcium from atherosclerotic plaques.AimThe present study aimed to explore the effects of calcium disodium ethylenediaminetetraacetic acid (CaNa2EDTA) and meso-2,3-dimercaptosuccinic acid (DMSA) on diet-induced hypercholesterolemia in rats using simvastatin as a reference standard.MethodsHypercholesterolemia was induced by feeding rats with cholesterol-rich diet for six weeks. Rats were divided into five groups (n=8): normal control, hypercholesterolemic control, simvastatin (20mg/kg; p.o.), CaNa2EDTA (100mg/kg; i.p.) and DMSA (100mg/kg; i.p.). Treatments continued daily for the six weeks of diet feeding.ResultsDiet-induced hypercholesterolemia resulted in alterations in the lipid profile markers and a state of oxidative stress coupled by compensatory increase in serum nitric oxide (NO) level and decreased aortic endothelial nitric oxide synthase (eNOS) activity parallel to increased inducible nitric oxide synthase (iNOS) activity, aortic calcium content and aortic wall thickness. Treatment with simvastatin, CaNa2EDTA and DMSA improved lipid profile and oxidative stress markers. In addition, they attenuated hypercholesterolemia-induced changes in serum NO level, aortic eNOS and iNOS activities, calcium content and aortic wall thickness.ConclusionPretreatment of hypercholesterolemic rats with simvastatin, CaNa2EDTA or DMSA attenuated most of the changes induced by feeding rats with cholesterol-rich diet owing to their observed anti-hyperlipidemic and antioxidant properties

Variations in genetic and chemical constituents of Ziziphus spina-christi L. populations grown at various altitudinal zonation up to 2227m height

AbstractAltitudinal gradient-defined specific environmental conditions could lead to genetics and chemical variations among individuals of the same species. By using RAPD, ISSR, GC–MS and HPLC analysis, the genetic and chemical diversity of Ziziphus spina-christi plants at various altitudinal gradient namely; Abha (2227.86m), Dala Valley (1424m), Rakhma Valley (1000m), Raheb Valley (505m) and Al-Marbh (147m) were estimated. RAPD markers revealed that the highest similarity value (40.22%) was between Raheb Valley and Al-Marbh while the lowest similarity (10.08%) was between Abha and Raheb Valley. Based on ISSR markers the highest similarity value (61.54%) was also between Raheb Valley and Al-Marbh, while the lowest similarity (26.84%) was between Abha and Rakhma Valley. GC–MS results showed the presence of various phytochemical constituents in each population. The dendrogram based on chemical compounds separated the Z. spina-christi grown at the highest elevations (Abha) from the populations in lower elevations. HPLC analysis showed that the leaves of Z. spina-christi plant contain considerable amount of vitamins including B1, B12, B2 and folic acid. In conclusion, there is a close relation between altitudinal gradients, genetic diversity and chemical constituents of the leaves of Z. spina-christi plants

Mineralogical Study and Restoration of the Lid of an Alabaster Sarcophagus in the Step Pyramid, Saqqara, Egypt

The pyramid of king Djoser in Saqqara is one of the oldest stone building in history. There are five levels of corridors under the pyramid. There are two alabaster sarcophaguses in the fifth level. It is thought that they are for two daughters of king Djoser, although they were found empty. The lid of one of these sarcophaguses were found broken into nine pieces. Mineralogical investigations by both X-Ray diffraction and polarizing microscope were required to help identifying the components of the alabaster lid. The obtained results revealed that mineralogical study should have been carried out to achieve the restoration processes. The restoration process was carried out. The broken pieces of the lid were collected and glued, the lid was put in its place and the sarcophagus was closed. A drill, stainless steel bars and an epoxy called Araldite AW 106 were used in the restoration process. The restoration process was completed successfully

Relation between early stages of diabetic retinopathy and early stages of diabetic kidney disease in patients with type 2 diabetes in Egypt

Background. Diabetes mellitus is a pandemic disease. Type 2 diabetes (T2DM) is the most common type. Diabetic retinopathy (DR) and diabetic kidney disease (DKD) are disabling chronic complications. The relation between both is not yet well-established in T2DM. Egypt is considered one of the top ten countries re- garding the prevalence of diabetes that makes diabetes and its complications a major health problem. This encouraged us to conduct this research.  Materials and methods. The study included 79 patients with T2DM divided into two groups according to the presence of retinopathy. Both groups were subdivided according to urinary albumin to creatinine ratio (UACR) into normoalbuminuric and albuminuric subgroups. Retinopathy group was further subdivided according to severity of retinopathy into mild, moderate and severe non-proliferative DR (NPDR). Statistical analysis was done and relation between the severity of retinopathy and UACR was studied.  Results. Patients with retinopathy had significantly higher diabetes duration and UACR than non retinopathy group. Also in subgroups of normoalbuminuria and albuminuria, retinopathy group was significantly higher regarding the same parameters. On subdividing the retinopathy group according to severity, severe NPDR group had significantly higher UACR. The severity of DR was significantly positively correlated with UACR.  Conclusions. The present study identified a significantly positive correlation between early stages of DR and UACR in patients with T2DM in Egypt. Not all cases of DR had DKD especially in early stages and also not all cases of DKD are associated with the presence of DR in T2DM.   Background. Diabetes mellitus is a pandemic disease. Type 2 diabetes (T2DM) is the most common type. Diabetic retinopathy (DR) and diabetic kidney disease (DKD) are disabling chronic complications. The relation between both is not yet well-established in T2DM. Egypt is considered one of the top ten countries re- garding the prevalence of diabetes that makes diabetes and its complications a major health problem. This encouraged us to conduct this research.  Materials and methods. The study included 79 patients with T2DM divided into two groups according to the presence of retinopathy. Both groups were subdivided according to urinary albumin to creatinine ratio (UACR) into normoalbuminuric and albuminuric subgroups. Retinopathy group was further subdivided according to severity of retinopathy into mild, moderate and severe non-proliferative DR (NPDR). Statistical analysis was done and relation between the severity of retinopathy and UACR was studied.  Results. Patients with retinopathy had significantly higher diabetes duration and UACR than non retinopathy group. Also in subgroups of normoalbuminuria and albuminuria, retinopathy group was significantly higher regarding the same parameters. On subdividing the retinopathy group according to severity, severe NPDR group had significantly higher UACR. The severity of DR was significantly positively correlated with UACR.  Conclusions. The present study identified a significantly positive correlation between early stages of DR and UACR in patients with T2DM in Egypt. Not all cases of DR had DKD especially in early stages and also not all cases of DKD are associated with the presence of DR in T2DM. 

1,3,4-Thiadiazoles and 1,3-thiazoles from one-pot reaction of bisthioureas with 2-(bis(methylthio)methylene)malononitrile and ethyl 2-cyano-3,3-bis(methylthio)acrylate

Bisthioureas reacted with either 2-(bis(methylthio)methylene)malononitrile or ethyl 2-cyano-3,3-bis(methylthio)acrylate to give 1,3,4-thiadiazoles and 1,3-thiazoles. Only, the reactive allyl derivative of bisthioureas reacted with the bis(methylthio)methylene compounds to give 1,3-thiazoles. The mechanism was discussed. The structures of products were proved by MS, IR, NMR and elemental analyses and X-ray structure analysis. [GRAPHICS]Peer reviewe

Twenty five-gauge sutureless vitrectomy versus 20-gauge vitrectomy in epiretinal membrane surgery

Purpose : To compare visual outcomes, intraoperative and postoperative complications of 25-gauge transconjunctival sutureless vitrectomy (25-G TSV) versus conventional 20-gauge vitrectomy in epiretinal membrane (ERM) surgery. Methods : A retrospective comparative study was conducted on 200 eyes with idiopathic ERM who underwent either primary 20-gauge vitrectomy (n=95) or 25-G TSV (n=105) with 6 months follow up. The following parameters were collected and compared : age, gender, best corrected visual acuity (BCVA), intraocular pressure (IOP), postoperative anterior chamber inflammation, intraoperative and postoperative complications. Results : Twenty-five gauge group achieved a significantly better vision at the 1st postoperative month (p=0.008) and a significantly higher incidence of visual improvement 6 months postoperatively (p=0.04) than 20-gauge group. Intraocular pressure was significantly higher at the 1st, 3rd and 6th postoperative months compared with baseline in the 20-G group. However, in the 25-gauge group IOP remained near to the baseline at the same period. Twenty five-gauge group achieved a significantly lower anterior chamber inflammation and a lower incidence of postoperative cystoid macular edema (CME) (p=0.01), hyphema (p=0.000) and after cataract (p=0.000) than 20-gauge group. Conclusions : The 25-gauge sutureless vitrectomy achieves rapid and higher visual improvement, less postoperative inflammation and complications than the 20-gauge vitrectomy in ERM surgery

Dietary clenbuterol modifies the expression of genes involved in the regulation of lipid metabolism and growth in the liver, skeletal muscle, and adipose tissue of Nile tilapia (Oreochromis niloticus)

The current study aimed to evaluate whether clenbuterol, a β2-adrenergic agonist, supplementation in Nile tilapia (Oreochromis niloticus) diets can influence growth and blood parameters. Besides, assessment of adipogenic genes as fatty acid synthase (FAS) and lipoprotein lipase (LPL) which is a key enzyme in the regulation of the flux of fatty acids in liver, muscle, and adipose tissue as well as muscle growth-regulating genes as myostatin (MYO) in muscle and insulin-like growth factor-1 (IGF-1) in liver. The fish were allocated into three equal groups; control group that fed basal diet only and the other two groups fed a basal diet containing clenbuterol at two doses 5 ppm and 10 ppm/kg diet for 30 consecutive days. Results revealed that clenbuterol supplementation significantly increased body weight, decreased liver, spleen and abdominal fat weights, and decreased total circulatory cholesterol and triacylglycerol levels. Moreover, clenbuterol inhibits lipogenesis by downregulation of FAS gene expression by dose and time-dependent manner in the liver while enhanced lipolysis in both the liver and in the adipose tissue. Moreover, lipolysis was reduced in muscle by dose 10 ppm on day 30. Furthermore, clenbuterol presented higher gene expression of MYO and IGF-1 in muscle and liver respectively by dose 5 ppm at day 15 on the other hand, these findings were reversed by day 30 compared with control. In conclusion, clenbuterol efficacy was apparent in a dose and time response pattern to boost growth and reduce fat deposition rates, indicating for the first time that clenbuterol has a profitable growth impact on Nile tilapia