Bias correction of regional climate model simulations for the impact assessment of the climate change in Egypt.

This study projected the future temperature change for Egypt during the late of this century (2071-2100) for three representative concentration pathways (RCP2.6, RCP4.5, and RCP8.5), by correcting regional climate model (RCM) simulations of average, maximum, and minimum daily temperature with reference to observed data of 26 stations. Four commonly used methods of bias correction have been applied and evaluated: linear scaling, variance scaling, and theoretical and empirical quantile mapping. The compromise programing results of the applied evaluation criteria show that the best method is the variance scaling, and thus it was applied to transfer the correction factor to the projections. All temperature indices are expected to increase significantly under all scenarios and reach the highest record by the end of the century, i.e., the expected increase in average, maximum, and minimum temperature ranges between 4.08-7.41 °C, 4.55-7.89 °C, and 3.88-7.23 °C, respectively. The largest temperature rise will occur in the summer, with the highest increase in the maximum (minimum) temperature of 10.9 °C (10 °C) in July and August under RCP8.5. The maximum (minimum) winter temperature, on the other hand, will drop by a maximum of 2 °C (1.35 °C) under RCP2.6. The Western Desert and Upper Egypt are the regions most affected by climate change, while the northern region of Egypt is the least affected. These findings would help in impact assessment and adaptation strategies and encourage further investigation to evaluate various climate models in order to obtain a comprehensive assessment of the climate change impacts on different hydrometeorological processes in Egypt.

Surface water quality management for drinking use in El-Beheira Governorate, Egypt.

This research was initiated to assess and manage water quality status of fourteen surface drinking water intakes in El-Beheira Governorate, Egypt. The study was conducted on four main branches of water resources in the governorate. Three water quality indices (WQIs) and two multivariate statistical techniques were applied, based on the Egyptian guidelines for the Nile River. Water quality records were collected for two successive years, 2014 and 2015, and were analyzed by descriptive statistics. The results revealed the critical water quality status of the four branches at the fourteen intakes. The multivariate statistical techniques returned the critical water quality conditions to the agricultural drainage and the domestic wastewater discharges. In addition, a new software application was developed to manage WQIs calculation. An urgent water quality monitoring and assessment system should be initiated for the drinking water resources all over Egypt, based on the developed water quality assessment techniques of this study. PRACTITIONER POINTS: Three different WQIs and two different statistics tools were applied. Critical water quality status for the investigated surface drinking water intakes was reported. Agricultural drainage then domestic effluents are the main pollution sources. A new software application was developed to calculate WQIs to support decision makers.

Numerical and experimental analyses of the use of double vertical barrier walls for groundwater protection.

The groundwater contamination and its impacts on the hydrologic systems and society are critical environmental concerns in the world. This research presents insights from the numerical (SEEP/W and CTRAN/W) and the experimental (sandbox model) analyses of the use of double vertical barrier walls for groundwater protection. The main objective was to evaluate contaminant transport under the effect of several variables. The arrival time increases with increasing the distance between the pollutant source and the first wall, first wall depth of penetration, the distance between the two walls and also increases at smaller hydraulic head differences, and lower conductivities. Furthermore, using double barrier walls would significantly reduce contaminant concentration at the downstream area. This control is most significant when the depth of first wall penetration is larger than that of the second wall. Results proved consistent with several similar studies and advantageous over many of them by the integrated use of both techniques with more variable parameters evaluated. PRACTITIONER POINTS: The research will introduce insights from the effect of using double barrier walls on the hydraulic control of contaminant transport. The effect of several variables on the contaminant arrival time and concentration is investigated. Using double barrier walls has a significant impact on contamination transport through the soil. This control is most significant when the penetration depth of the first wall is larger than that of the second.

Biocontrol efficacy of Trichoderma asperellum-enriched coconut fibre against Fusarium wilts of cherry tomato.

AIMS: Agro-based wastes were evaluated as a medium for mass micropropagule production and optimal efficacy of Trichoderma asperellum B1092 in controlling Fusarium oxysporum f. sp. lycopersici and promoting tomato growth. This study focused on biological control because pathogen persistence in the soil makes the disease difficult to control. METHODS AND RESULTS: Rice bran, biochar, empty fruit bunches, coconut fibres, compost, top soil and mixed soil were evaluated as media for mass multiplication of T. asperellum, which is effective in controlling plant pathogens. Yielding the most colony forming units (CFU) among the media, coconut fibre was deemed most suitable for promoting sporulation. After 120 days on the medium, T. asperellum B1902 produced 9·053 × 105  CFU per gram coconut fibre; oil palm empty fruit bunches was second highest (7·406 × 105  CFU per gram). In field tests of T. asperellum B1092 against F. oxysporum f. sp lycopersici (causing Fusarium wilt of cherry tomato), B1092 significantly promoted plant growth compared to the control. The efficacy of this formulation resulted in increased growth of roots and shoots tomato plants and total lycopene, sugar, K, N, Ca, P and Mg content after 120 days. CONCLUSIONS: Trichoderma asperellum B1092 showed great field potential for improving productivity and quality of tomatoes and in controlling Fusarium wilt of cherry tomato. SIGNIFICANCE AND IMPACT OF THE STUDY: This innovative approach using a cheap agro-waste to control the persistent soil-borne Fusarium pathogen of cherry tomato should increase soil survival rate of Trichoderma and has potential for upscaling in the field for other crops.

Failure behavior of sandwich honeycomb composite beam containing crack at the skin.

Skin crack defects can develop in sandwich honeycomb composite structures during service life due to static and impact loads. In this study, the fracture behavior of sandwich honeycomb composite (SHC) beams containing crack at the skin was investigated experimentally and numerically under four-point loading. Three different arrangements of unidirectional (UD) carbon fiber composite and the triaxially woven (TW) fabric were considered for the skins. The presence of a 10 mm crack at mid-span of the top skin, mid-span of the bottom skin, and mid-way between load and support of the top skin, respectively, were considered. Failure load equations of the load initiating the skin crack extension were analytically derived and then numerically developed using the J-integral approach. The crack extension failure mode dominated all cracked specimens except those with low-stiffness skin which were controlled by the compressive skin debonding and core shear failures.

Stochastic models in seed dispersals: random walks and birth-death processes.

Seed dispersals deal with complex systems through which the data collected using advanced seed tracking facilities pose challenges to conventional approaches, such as empirical and deterministic models. The use of stochastic models in current seed dispersal studies is encouraged. This review describes three existing stochastic models: the birth-death process (BDP), a 2 dimensional ( 2D ) symmetric random walks and a 2D intermittent walks. The three models possess Markovian property, which make them flexible for studying natural phenomena. Only a few of applications in ecology are found in seed dispersals. The review illustrates how the models are to be used in seed dispersals context. Using the nonlinear BDP, we formulate the individual-based models for two competing plant species while the cover time model is formulated by the symmetric and intermittent random walks. We also show that these three stochastic models can be formulated using the Gillespie algorithm. The full cover time obtained by the symmetric random walks can approximate the Gumbel distribution pattern as the other searching strategies do. We suggest that the applications of these models in seed dispersals may lead to understanding of many complex systems, such as the seed removal experiments and behaviour of foraging agents, among others.

Feature Map Quality Score Estimation Through Regression.

Understanding the visual quality of a feature map plays a significant role in many active vision applications. Previous works mostly rely on object-level features, such as compactness, to estimate the quality score of a feature map. However, the compactness is leveraged on feature maps produced by salient object detection techniques where the maps tend to be compact. As a result, the compactness feature fails when the feature maps are blurry (e.g., fixation maps). In this paper, we regard the process of estimating the quality score of feature maps, specifically fixation maps, as a regression problem. After extracting several local, global, geometric, and positional characteristic features from a feature map, a model is learned using a random forest regressor to estimate the quality score of any unseen feature map. Our model is specifically tailored to estimate the quality of three types of maps: bottom-up, target, and contextual feature maps. These maps are produced for a large benchmark fixation data set of more than 900 challenging outdoor images. We demonstrate that our approach provides an accurate estimate of the quality of the abovementioned feature maps compared to the groundtruth data. In addition, we show that our proposed approach is useful in feature map integration for predicting human fixation. Instead of naively integrating all three feature maps when predicting human fixation, our proposed approach dynamically selects the best feature map with the highest estimated quality score on an individual image basis, thereby improving the fixation prediction accuracy.

Catalytic, kinetic and thermodynamic properties of Bacillus pumilus FH9 keratinase conjugated with activated pectin.

Bacillus pumilus FH9 keratinase was covalently coupled to several oxidized polysaccharides. The conjugates were evaluated for the retained activity, kinetic and thermodynamic stability. Among all preparations, the conjugated enzyme with oxidized pectin had the highest recovered activity (71.75%) and the highest thermal stability at 60°C (t1/2=333 min). Compared to the native enzyme, the conjugated preparation exhibited higher optimum temperature, lower activation energy (Ea), lower deactivation constant rate (kd), higher t1/2, and higher decimal reduction time values (D) within the temperature range of 50-80°C. The thermodynamic parameters (ΔH*, ΔG*, ΔS*) of irreversible thermal denaturation for the native and conjugated keratinase were also evaluated. The values of enthalpy of activation (ΔH*), free energy of activation (ΔG*), and free energy of transition state binding (ΔG*E-T) for keratin hydrolysis were lower for the conjugated enzyme. Moreover, there was highly significant impact on improving the values of Vmax/Km, kcat, kcat/Km, and ΔG*E-S for the modified enzyme. Both native and conjugated enzymes were slightly activated by CaCl2 and MgCl2. However, the inhibitory effects of EDTA, HgCl2 and ZnSO4 were more pronounced with the native enzyme.

Benign prostate hyperplasia: average volume in southwestern Nigerians and correlation with anthropometrics.

OBJECTIVES: To determine the prevalent age of symptomatic benign prostate hyperplasia (BPH), the average BPH volume, and the association between BPH volumes and the age, and anthropometrics in our immediate black community. PATIENTS, MATERIALS AND METHOD: Selected patients with lower urinary tract symptoms (LUTS) due to BPH with tissue diagnosis, and adult men of similar age group with no irritative or obstructive LUTS were prospectively studied from July 2003 to June 2009. The age, height and weight were recorded, prostate volumes determined with ultrasound, body mass index (bmi) calculated, and correlations determined between the prostate volume and the age, and anthropometrics. RESULTS: 105 patients aged 43-88 yrs (mean=64.4, 8.88 SD) managed for BPH were studied with 93 asymptomatic men aged 43-80 yrs (mean=56.15, 9.89 SD). The mean (SD) prostate volume, height, weight and bmi were 83.8 (37.7) ml, 1.67 (0.07) m, 63.6 (9.32) kg and 22.8 (3.03) kg/m2, and 24.5 (9.2) ml, 1.69 (0.06) m, 68.9 (10.6) kg and 24.2 (3.44) kg/m2 respectively for symptomatic and asymptomatic groups. In the symptomatic group, BPH volume showed significant positive correlation with the age (p=0.030), but no correlation with the weight (p=0.550), height (p=0.375) and bmi (p=0.840). In the asymptomatic group, prostate volume also showed significant positive correlation with the age (p=0.041), but no correlation with the weight (p=0.434), height (p=0.394), and bmi (p=0.203). CONCLUSION: The prevalent age of symptomatic BPH in our community is 43- 88 years with 83.79 (37.66) ml mean (SD) volume in symptomatic patients and 24.45 (9.21) ml in asymptomatic men. BPH volume correlates with age but not with anthropometrics. Lack of correlation with BPH volume suggests that anthropometrics may not be risk factors for development of BPH in our community.

Benign prostate hyperplasia: average volume in southwestern Nigerians and correlation with anthropometrics.

AIMS AND OBJECTIVES: To determine the prevalent age of symptomatic benign prostate hyperplasia (BPH), the average BPH volume, and the association between BPH volumes and the age, and anthropometrics. PATIENTS, MATERIALS AND METHODS: Selected patients with lower urinary tract symptoms (LUTS) due to BPH with tissue diagnosis, and adult men of similar age group with no irritative or obstructive LUTS were prospectively studied from July 2003 to June 2009. The age, height and weight were recorded; prostate volumes determined with ultrasound, body mass index (BMI) calculated, and correlations determined between the prostate volume, the age and anthropometrics. RESULTS: One hundred and five patients aged 43-88years (mean=64.4, 8.88SD) managed for BPH were studied with 93 asymptomatic men aged 43-80years (mean=56.15, 9.89SD). The mean (SD) prostate volume, height, weight and BMI were 83.8(37.7) ml, 1.67(0.07) m, 63.6(9.32) kg and 22.8(3.03) kg/m2, and 24.5(9.2) ml, 1.69(0.06) m, 68.9(10.6) kg and 24.2(3.44) kg/m2 respectively for symptomatic and asymptomatic groups. In the symptomatic group, BPH volume showed significant positive correlation with the age (p=0.030), but no correlation with the weight (p=0.550), height (p=0.375) and BMI (p=0.840). In the asymptomatic group, prostate volume also showed significant positive correlation with the age (p=0.041), but no correlation with the weight (p=0.434), height (p= 0.394), and BMI (p=0.203). CONCLUSION: The prevalent age of symptomatic BPH in our community is 43-88years with 83.79(37.66) ml mean (SD) volume in symptomatic patients and 24.45(9.21) ml in asymptomatic men. BPH volume correlates with age but not with anthropometrics. Lack of correlation with BPH volume suggests that anthropometrics may not be risk factors for development of BPH.

Evaluation of tension-free mesh inguinal hernia repair in Nigeria: a preliminary report.

BACKGROUND: Tension-free mesh inguinal hernia repair is becoming increasingly popular worldwide. However, reports are sparse in Nigeria. OBJECTIVE: To evaluate the impact, outcome and cost implication of tension free inguinal hernia repair in a Nigerian setting. METHODS: A prospective study of all consecutive adults patients with uncomplicated inguinal hernia who had mesh repair over a period of 12 months was undertaken. A large sheet of 900cm2 polyproylene mesh material was used for all the patients in the study. All wounds were opened on the third postoperative day while sutures were removed on the eight day. Patients were followed up for one year. RESULTS: A total number of 30 patients had tension-free mesh ingunal hernia repair. Their ages ranged from 21 to 78 years (mean 47.2±15.5) years with a female to male ratio of 1:15. Complete inguinoscrotal hernia was the commonest type of groin hernia accounting for 40% of the cases. The repair of posterior wall which entailed placement of mesh was completed at a median time of 15 minutes. While two (6.7%) and one (3.3%) had wound oedema and groin pain respectively at one month, none of the patients had these complications or recurrence at a median of five months follow-up period. CONCLUSION: Tension-free mesh inguinal hernia repair was well tolerated and affordable to our patients. Pain and infections, reported to be the common complications of this procedure were infrequent in this study. A larger study is recommended to help confirm these findings.

Isolation and characterization of new poly(3HB)-accumulating star-shaped cell-aggregates-forming thermophilic bacteria.

AIMS: This study aimed at isolating thermophilic bacteria that utilize cheap carbon substrates for the economically feasible production of poly(3-hydroxybutyrate), poly(3HB), at elevated temperatures. METHODS AND RESULTS: Thermophilic bacteria were enriched from an aerobic organic waste treatment plant in Germany, and from hot springs in Egypt. Using the viable colony staining method for hydrophobic cellular inclusions with Nile red in mineral salts medium (MSM) containing different carbon sources, six Gram-negative bacteria were isolated. Under the cultivation conditions used in this study, strains MW9, MW11, MW12, MW13 and MW14 formed stable star-shaped cell-aggregates (SSCAs) during growth; only strain MW10 consisted of free-living rod-shaped cells. The phylogenetic relationships of the strains as derived from 16S rRNA gene sequence comparisons revealed them as members of the Alphaproteobacteria. The 16S rRNA gene sequences of the isolates were very similar (>99% similarity) and exhibited similarities ranging from 93 to 99% with the most closely related species that were Chelatococcus daeguensis, Chelatococcus sambhunathii,Chelatococcus asaccharovorans, Bosea minatitlanensis, Bosea thiooxidans and Methylobacterium lusitanum. Strains MW9, MW10, MW13 and MW14 grew optimally in MSM with glucose, whereas strains MW11 and MW12 preferred glycerol as sole carbon source for growth and poly(3HB) accumulation. The highest cell density and highest poly(3HB) content attained were 4·8g l(-l) (cell dry weight) and 73% (w/w), respectively. Cells of all strains grew at temperatures between 37 and 55°C with the optimum growth at 50°C. CONCLUSIONS: New PHA-accumulating thermophilic bacterial strains were isolated and characterized to produce poly(3HB) from glucose or glycerol in MSM at 50°C. SSCAs formation was reported during growth. SIGNIFICANCE AND IMPACT OF THE STUDY: To the best of our knowledge, this is the first report on the formation of SSCAs by PHA-accumulating bacteria and also by thermophilic bacteria. PHA-producing thermophiles can significantly reduce the costs of fermentative PHA production.

Modeling of hexamethylene diisocyanate and psychrometric parameters and other effective factors in the polyurethane factories.

BACKGROUND: Diisocyanates are widely used in surface coatings, polyurethane (PUR) foams, adhesives, resins, elastomers, binders, and sealants. Isocyanate exposure is irritative to the skin, mucous membranes, eyes, and respiratory tract. The most common adverse health outcome associated with isocyanate exposure is asthma due to sensitization. OBJECTIVE: The goal of this study is to find statistical predictive model to determine the relationship between airborne hexamethylene diisocyanate (HDI) and selective psychrometric variables. MATERIALS AND METHODS: All air samplers (by midget impinger) were collected by mini personal sampler pump fixed to work stations near the source of pollution. The air samples and psychrometric parameters were separately collected and determined in a working shift for three periods of 2 h, each at a flow rate of 2 l/min in an impinger containing a solution of reagent of dimethyl sulfoxide in tryptamine [US National Instituteof Occupational Safety and Health (NIOSH), 1994]. RESULTS: There was a significant correlation between HDI concentration and relative humidity and dry bulb temperature (P < 0.05). No significant correlation was seen between altitude and dimension of PUR factories (P > 0.05). CONCLUSIONS: The finding of the study may be a useful initial tool in estimating possible HDI pollution situation in the PUR workplaces, based on simple psychrometric factors (indoor air temperature and relative humidity).

Zobellella denitrificans strain MW1, a newly isolated bacterium suitable for poly(3-hydroxybutyrate) production from glycerol.

AIMS: To search for new bacteria for efficient production of polyhydroxyalkanoates (PHAs) from glycerol. METHODS AND RESULTS: Samples were taken from different environments in Germany and Egypt, and bacteria capable of growing in mineral salts medium with glycerol as sole carbon source were enriched. From a wastewater sediment sample in Egypt, a Gram-negative bacterium (strain MW1) was isolated that exhibited good growth and that accumulated considerable amounts of polyhydroxybutyrate (PHB) from glycerol and also from other carbon sources. The 16S rRNA gene sequence of this isolate exhibited 98.5% and 96.2% similarity to Zobellella denitrificans strain ZD1 and to Zobellella taiwanensis strain ZT1 respectively. The isolate was therefore affiliated as strain MW1 of Z. denitrificans. Strain MW1 grows optimally on glycerol at 41 degrees C and pH 7.3 and accumulated PHB up to 80.4% (w/w) of cell dry weight. PHB accumulation was growth-associated. Although it was not an absolute requirement, 20 g l(-1) sodium chloride enhanced both growth (5 g cell dry weight per litre) and PHB content (87%, w/w). Zobellella denitrificans strain MW1 is also capable to accumulate the poly(3-hydroxybutyrate-co-3-hydroxyvalerate) copolymer if sodium propionate was used as cosubstrate in addition to glycerol. CONCLUSIONS: A new PHB-accumulating strain was isolated and identified. This strain is able to utilize glycerol for growth and PHB accumulation to high content especially in the presence of NaCl that will enable the utilization of waste glycerol from biodiesel industry. SIGNIFICANCE AND IMPACT OF THE STUDY: This study is the first report on accumulation of PHA in a member of the new genus Zobellella. Furthermore, utilization of glycerol as the sole carbon source for fast growth and PHB biosynthesis, growth in the presence of NaCl and high PHB contents of the cells will make this newly isolated bacterium a potent candidate for industrial production of PHB from crude glycerol occurring as byproduct during biodiesel production.

Scavenging behaviour of meranti sawdust in the removal of methylene blue from aqueous solution.

Meranti (Philippine mahogany) sawdust, an inexpensive material, showed strong scavenging behaviour through adsorption for the removal of methylene blue (MB) from aqueous solution. Batch studies were performed to evaluate and optimize the effects of various parameters such as contact time, pH, initial dye concentrations and adsorbent dosage. Langmuir, Freundlich and Temkin isotherms were used to analyze the equilibrium data at different temperatures. The experimental data fitted well with the Langmuir adsorption isotherm, indicating thereby the mono layer adsorption of the dye. The monolayer sorption capacity of meranti sawdust for MB was found to be 120.48, 117.64, 149.25 and 158.73 mg/g at 30, 40, 50 and 60 degrees C, respectively. Thermodynamic calculations showed that the MB adsorption process is endothermic and spontaneous in nature. Kinetic studies showed that the adsorption followed a pseudo-second-order kinetic model. The results indicated that the meranti sawdust could be an alternative material in place of more costly adsorbents used for dye removal.

Low-dose quinine is effective in the treatment of chloroquine-resistant Plasmodium falciparum malaria in eastern Sudan.

In November-December 2002, 98 patients presented at the Elhara Eloula health centre, in the New Halfa area of eastern Sudan, with Plasmodium falciparum malaria that had failed to respond to chloroquine treatment. After informed consent was obtained, 93 of these patients were randomly allocated to one of three regimens for quinine treatment, being given the drug, orally and sometimes intravenously, for 7 days, at doses of 10 mg/kg thrice daily (32 patients), 10 mg/kg twice daily (31 patients) or 15 mg/kg once daily (30 patients). All the patients were followed daily until day 7 and then weekly until day 28. There was no significant difference in the parasite-clearance times observed in the three groups. Parasitaemias re-occurred by day 28 in 12 patients: two (6.3%) of the patients treated thrice daily, five (16.1%) of those treated twice daily, and five (16.7%) of those treated once daily (P > 0.05). Genotyping indicated that in nine of these 12 patients the parasitaemias that developed post-treatment represented true recrudescences and not re-infections. In the treatment of chloroquine-resistant, P. falciparum malaria in Sudan, once-daily treatment with quinine, in a relatively low daily dose (15 mg/kg. day), appears as effective as the thrice-daily treatment (at 30 mg/kg. day) often recommended.

Efficacy of sulfadoxin pyrimethamine for uncomplicated Plasmodium falciparum malaria in a small sample of Sudanese children.

A prospective clinical trial was carried out to determine in vivo efficacy of sulfadoxine/pyrimethamine for the treatment of uncomplicated Plasmodium falciparum malaria in children in New Halfa. Forty patients were enrolled; 31 completed the 28-day follow-up. Six (19.4%) patients showed recurrence of parasitaemia during follow-up, while the rest (80.6%) cleared the parasites and responded fully to treatment. All the failures were late treatment failures. Parasite genotyping showed that 1 (16.7%) of the 6 cases of late parasitaemia was due to reinfection while the rest (83.4%) were due to true recrudescence. During the follow-up period 22.6% of patients showed gametocytaemia. The high level of treatment failure as well as gametocytaemia necessitates the introduction of artesunate in this combination therapy.

Low-dose quinine for treatment of chloroquine-resistant falciparum malaria in Sudanese pregnant women.

Pregnant Sudanese women who presented at a hospital in eastern Sudan with chloroquine-resistant falciparum malaria were randomly allocated to one of two quinine regimens: low-dose (10 mg/kg 2 times/day) (18 patients) or standard (10 mg/kg 3 times/day) (24 patients). Treatment was for 7 days and follow-up for 28 days. Significantly fewer patients in the low-dose group reported vomiting and abdominal pain than the standard regimen group. Hypoglycaemia, preterm labour and recrudescence were slightly but not significantly higher in patients in the standard group than low-dose group. There were no significant differences between the groups in the mean time from admission to remission of fever and parasite clearance. We tentatively advocate the use of quinine 2 times/day to reduce side-effects and improve compliance.