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BACKGROUND Acne vulgaris (AV) is an inflammatory skin disorder that may be associated with metabolic disorders. The relation between lipid profile in acne is not widely investigated. Chitinase-3-like protein 1 (YKL-40) has been found to be implicated in different inflammatory conditions. AIMS We aimed at investigating the role YKL-40 in acne pathogenesis and associated dyslipidemia in acne patients. PATIENTS/METHODS This study included 50 acne vulgaris patients and 30 matched control subjects. Serum YKL-40 in addition to lipid profile were assessed in all studied subjects. RESULTS Serum YKL-40 level was significantly elevated in acne patients than healthy controls (P

Saldırı tespit sistemleri bilgi güvenliğinde önemli bir rol oynamaktadır. Elektronik saldırıların artması nedeniyle bilgi güvenliği tüm dünyada önemli bir konu haline gelmektedir. Klasik makine öğrenim yöntemleri (Yapay Sinir Ağları (YSA), Naive Bayes (NB) Ve Destek Vektör Makineleri (DVM) vb.) ağdaki bilinmeyen saldırılar için bilgisayar ağları için iyi izinsiz giriş tespit oranları üretmekte fakat düşük yanlış alarm oranları üretmektedir. Son zamanlarda, makine öğrenmesinin gelişimi derin öğrenmenin keşfedilmesine neden olmuştur. Derin öğrenme ağları, çeşitli sınıflandırıcıları eğitmek ve izinsiz giriş tespitinde en iyi oranları elde etmek için klasik makine öğrenme modellerinden daha iyi seçenekler sunmaktadır. Bu çalışmada, Konvolüsyonel Sinir Ağları - Ağ Saldırı Tespit Sistemini (KSA-ASTS) modeli bilgisayar ağlarında saldırı tespiti geliştirmek için kullanılmıştır. Konvolüsyonel Sinir Ağları görüntü sınıflandırma için çok etkili bir algoritmadır. Bu çalışmada dijital veriler görüntülere dönüştürülmüş ve konvolüsyonel sinir ağı eğitilmiştir. KSA-ASTS kullanılarak ağ izinsiz giriş saptama probleminde kullanılan modelin performansını değerlendirmek için, NSL-KDD veri seti kullanılmıştır. Sonuçların değerlendirilmesi iki farklı sınıflandırma sistemi (ikili ve çok sınıflı sınıflandırma sistemleri) kullanılarak yapılmıştır. İkili sınıflandırma sistemi, saldırı ve normal olmak üzere iki seçenek içerirken, çoklu sınıflandırma sistemi normal, DoS, R2L, Probe ve U2R olarak beş seçenek içermektedir. Sonuçlar, ağ izinsiz tespit sisteminin gerçekleştirilmesi için Konvolüsyonel Sinir Ağları'nın kullanılmasının, diğer yöntemlere kıyasla önemini ortaya koymuştur. Bu model izinsiz giriş tespit sisteminin geliştirilmesinde kullanılabilir. Intrusion Detection Systems is considered a main factor in information security. With the increasing of electronic attacks, the safety of information became an important affair of all over the world. The classical machine learning models (e.g. Neural Networks (NN), Naive Bayes (NB) and Support Vector Machines (SVM), etc.) have produced good intrusion detection rates but low false alarm rates for computer networks for unknown attacks in the network. Recently, the development of machine learning led to discovering deep learning. Deep learning networks are presenting better options than the classical machine learning models to train various classifiers and get the better rates in intrusion detection. In this study, a Convolutional Neural Network - Network Intrusion Detection System (CNN-NIDS) model is proposed for improving intrusion detection in computer networks. The Convolutional Neural Network has proven very effective in image classification. So, the digital data has been converted to images and Convolutional Neural Network trained. A full data set NSL KDD is used for the assessment of the performance of the model used in network intrusion detection problem using (CNN-NIDS). The assessment of the results is made using two classification systems Binary and Multi class classification systems. The binary classification system includes two options, Attack and Normal, whereas the multi class classification system includes 5 options, normal, DoS, R2L, Probe, and U2R. The results revealed the importance of using Convolutional Neural Networks for the improvement of Network Intrusion detection system compared with other methods. This model can be used for the improvement of Intrusion Detection system. 74

Clinically approved iron chelators are effective in decreasing significant transfusional iron accumulation. Starch-Deferoxamine (S-DFO), a novel high molecular weight iron chelator, was produced to increase binding capacity to iron and reduce toxicity. Although its efficacy was established in one small cohort clinical trial, its potential adverse effect was not adequately addressed. We utilized zebrafish model to assess S-DFO toxicity using following assays: mortality, teratogenicity, hatching rate, tail flicking, Acridine Orange staining for apoptosis detection, o-dianisidine staining for hemoglobin synthesis, and the level of Hsp70 as a general stress indicator. Embryos were exposed to different concentrations of S-DFO, Zinc Oxide nanoparticle (ZnO) (positive control), along with untreated control (UC). S-DFO showed no significant mortality nor deformities at all tested concentrations (0.0-1000 μM). Thus, the LC50 is expected to >1000 μM. 100 μM S-DFO treatment did not affect embryo development (as judged by hatching rate); neuromuscular activity (as judged by tail flicking); and hemoglobin synthesis. Neither apoptosis, nor increase in Hsp70 level was noticed upon S-DFO treatment. Our assays demonstrate that S-DFO does not induce cellular or biochemical stress and has no adverse effect on organ development of zebrafish embryos, suggesting its safe use as an iron chelator. Funding information: Qatar University, Grant/Award Number: University Internal Grant/QUUG-CAS-DHS-15\16-21.

For more than 50 years, artificial joints are fastened efficiently by bone cements. Bone cements play an important role in the elastic zone. In human hip joint, about ten to twelve times of the body weight acts upon the hip joint. This gives rise to the need of the bone cement to absorb the forces acting upon the human hip joint. Plexiglas, which is Poly Methyl Methacrylate (PMMA) is the material of choice for obtaining bone cements. Three methods are conducted to produce PMM4; namely, the emulsion polymerization, solution polymerization and bulk polymerization. From these methods; in-situ and in-vivo extremely exothermic reactions of free radical bulk polymerization are used to produce PMM4 bone cements. Radical polymerization gives atactic and amorphous PMM4. Also, aseptic loosening is caused by residual monomer which remains unreacted in the body. Free radical polymerization models can describe the bone cement production effectively and are used for quantitative analysis of its synthesis. In this research, bone cement production is mathematically investigated based on multi-cell reactor. Solubility of the pre-polymer powder in the liquid monomer has shown to be the most important variable during the preparation process and that it should be tuned to control the real operation of bone cement production.

This paper presents the balance control design using Robust Generalized Dynamic Inversion (RGDI) for Rotary Double Inverted Pendulum (RDIP) system. The RGDI control comprised of the particular part and the robust control element. The particular part is responsible to enforce the constraint dynamics based on the attitude deviation functions, and is inverted using Moore-Penrose Generalized Inverse (MPGI) to obtain the control law. An additional robust term based on the concept of sliding mode is integrated to enhance the robust characteristics against system nonlinearities, uncertainties and disturbances. The singularity problem is addressed by incorporating a dynamic scale factor in the expression of MPGI. The proposed RGDI control will guarantee semi-global practically stable angular position tracking of the horizontal rotary arm and the stabilization of the two pendulums at the upright position. Numerical simulations are carried out on the RDIP simulator to analyze the controller performance.

As one of the most promising topics in complex control processes, data-driven techniques have been widely used in numerous industrial sectors and have developed over the past two decades. In addition, the fractional-order controller has become more attractive in applied studies. In this article, a fractional integral control is implemented for a rotary flexible joint system. Moreover, an adjusted virtual reference feedback tuning (VRFT) technique is used to tune the fractional-order integrator. In this method, fractional integral control is designed based on state feedback control. Then, VRFT is adjusted and applied to the fractional integral controller. The effectiveness of the proposed adjusted VRFT method is discussed and presented through simulation and experimental results. The tracking performance of the rotary arm and the minimization of the vibration tip is evaluated based on the proposed method. In this article, the comparison of our proposed VRFT fractional scheme is made with the classical state feedback as well as a recently developed state feedback-based fractional order integral (SF-FOI) controller. The current investigations determine the performance improvement of our proposed scheme of comparable structure to the recent SF-FOI, with the introduction of the VRFT to the SF-FOI scheme.

In this paper, the effect of β-amyloid (Aβ) oligomer aggregates on Acetylcholine (ACh) neurocycle of human brain and its relation to Alzheimer's disease (AD) are investigated through a two-enzyme/two-compartment (2E2C) diffusion mathematical model whereby compartment 1 represents the presynaptic neuron while compartment 2 represents the postsynaptic neuron and postsynaptic cleft. It is found that Aβ aggregates induce choline leakage from the presynaptic neurons (compartment 1) leading to a reduction in choline content in both compartments. The lowering in choline levels in each compartment is promoted with the increase in the inlet Aβ oligomers which create more channels and pores in the presynaptic membrane. In addition, it is found that both the rates of ACh synthesis and hydrolysis were affected negatively by the increase in the levels of Aβ oligomers. Furthermore, the levels of ACh in both compartments decreased while the level of Aβ oligomers increased. However, the acetate concentration in compartment 1 increased but the acetate level in compartment 2 decreased. These results are compatible with the low levels of both ACh and choline in the neuron tissues of Alzheimer's disease (AD) brains through choline leakage hypothesis. Also, the model shows the significant effect of inhibiting Aβ aggregation as a promising therapeutic mechanism to mitigate cholinergic diseases. The model suggests that Aβ oligomers exert neuroinflammatory and toxic effect against the ACh neurocycle. The paper suggests that development of therapeutic agents capable of inhibiting toxic Aβ aggregations and maintaining choline substrates in neurons is necessary to provide a neuroprotective effect, cholinergic transmission, and maintain reasonable levels of ACh.

This paper has studied the metal–insulator-semiconductor (MIS) contact for both p- and n-InGaN. We found that the insulator layer thickness has a remarkable effect on the Fermi level pinning and barrier height reduction in MIS contacts. Schottky's formation with doped InGaN is explained by extending the MIS contacts' using the metal-induced gap states (MIGS) model. The J-V characteristics clarify the current transport mechanism through the MIS contact with InGaN semiconductor for different temperatures. We observed less control on the barrier height reduction in the case of n-InGaN through changing the thickness of the interfacial layer. The calculated contact resistivities of MIS contact with p- and n-InGaN show better results than the metal–semiconductor contact counterparts. These findings are highly significant to design and fabricate the InGaN based switching devices for converter applications.

In this paper, an original model-based analytical method is developed to design a fractional order controller combined with a Smith predictor and a modified Smith predictor that yield control systems which are robust to changes in the process parameters. This method can be applied for integer order systems and for fractional order ones. Based on the Bode's ideal transfer function, the fractional order controllers are designed via the internal model control principle. The simulation results demonstrate the successful performance of the proposed method for controlling integer as well as fractional order linear stable systems with long time delay.

The down-regulation of CD3 protein present on the surface of a T-cell triggers the process of activation. A rapid decrease of CD3 from the surface is required to reach the threshold that is necessary for the continuation of the activation process. Using the flow cytometry technique, it is well established that an amount of down-regulated CD3 proteins recycle and may appear on the surface of T-cell. This article studies the impact of recycled CD3 protein that is recruited into the immune synapse at different rates. The population density of T-cells is distributed over surface protein (CD3) concentration under the framework of population balance models by using a coupled system of PDEs. Such problems need non-conventional population balance modelling so that classical numerical techniques can be applied. A recently developed efficient numerical method is validated against the analytical and numerical solutions. This article is protected by copyright. All rights reserved

The aim of this paper is to discuss the stability of a symmetric cross-ply composite laminated piezoelectric plate subject to combined excitations. Multiple timescale perturbation method is implemented to solve the nonlinear governing equations including the second-order approximation. The case of 1:1:3 internal resonance and primary resonance case is investigated. The stability of the system is discussed using frequency, force response curves. A bifurcation analysis was performed using the amplitude of parametric excitation force as the bifurcation parameter. It is found that there are two Hopf bifurcation points: the first one is at $$f_{11}=5.592$$ , and the other one is at $$f_{11}=13.96$$ . It is observed that the system is dominated by the periodic attractor in the ranges of $$(5.592< f_{11 }< 7.21)$$ and $$(13.31< f_{11 }< 13.96)$$ . The system is enriched with period doublings which are the main way leading to chaotic behavior. Some recommendations regarding the parameters limit of the dynamic system are reported.

Economic environment is actual and influences business activities significantly. Economic environment includes microeconomic and macroeconomic factors. These factors assist in encouraging business and promote trade and investment activities. This work aims to illustrate those factors, their characteristics and how do they support international business activities. This paper also is intended to reveal the indicators used to classify countries’ development for instance BOP, GNI, GDP and GNP. As a result, it also demonstrates the indicators’ characteristics and how these indexes work.

In this paper, fractional-order controller designs for integer first-order plus time delay systems are investigated. Based on Bode’s ideal transfer function as a reference model, a new structure of the fractional-order controller is proposed. The internal model control principle is used to design the controllers. The effectiveness of the controllers is demonstrated through simulations and their efficiency is validated through experimentation on a heat flow platform.

This work was carried out to investigate the comparative effects of phosphorus and boron doing in vapor–liquid–solid (VLS) growth. Doped Si microneedles were grown by VLS mechanism at the temperature of 700 °C or less using Au as the catalyst. VLS growth using in-situ doping with the mixed gas of Si2H6 and PH3 produced phosphorus doped n-Si microneedles at Au dot sites, whereas, the mixed gas of Si2H6 and B2H6 produced boron doped p-Si microneedles. The variation of growth rate, diameter, resistivity, impurity concentration and carrier (electron, hole) mobility of these n-Si and p-Si microneeedles were investigated and compared with the variation of dopant gas (PH3 or B2H6) flow, with a fixed flow of Si gas (Si2H6). This comparative study shall be helpful while fabricating devices by growing n-Si and p-Si microneedles one above another by multistep (2-step or 3-step) VLS growth.

In Faranah Province (Guinea), the ratio of supply and demand of corn is approximately 1:2. The production is low and the deficit is covered by maize importation. This study was initiated in order to improve corn production by evaluating the effects of increasing doses of mineral fertilizers on the yield and economic profitability of corn. The experiment was conducted on a farm in Kamedankoude in a split plot with three replicates. Treatments included two varieties of maize (Perta and Kilissi113) and five doses of chemical fertilizers (D0=unfertilized control, D1=300 kg NPKS+200 kg urea • hm−2; D2=400 kg NPKS+800 kg urea • hm−2; D3= 200 kg NPKS+400 kg urea • hm−2 and D4=500 kg NPKS+600 kg urea • hm−2). The results showed that all the agronomic parameters increased with increasing dose of fertilizers, except for the number of ears per plant. The two varieties of corn tested produced similar yields. However, the profitability of mineral fertilizers decreased with increased doses and with value/cost ratio of 3. We recommended a mineral fertilizer dose of 300 kg NPKS + 200 kg urea. The high prices of mineral fertilizers were often barriers to intensive maize cultivation, especially for low-income farmers. This study was a contribution to rational fertilization and adapted the socio-economic conditions of the region, with the background knowledge that most farmers in the regions earned low incomes.

Background Cathepsin C gene (CTSC) (MIM# 602365 ) is a lysosomal cysteine proteinase coding gene which encodes for CTSC protein that plays a major role in the activation of granule serine proteases, particularly leukocyte elastase and granzymes A and B. This activity was proposed to play a role in epithelial differentiation and desquamation. Mutations that cause Disruption in the CTSC expression or function will result in loss of immunological response such as defects of phagocytic function and deregulation of localized polymorphonuclears response with subsequent clinical manifestation. Aim The aim of this study is to detect the mutation in CTSC gene expected to be the cause of Papillon Lefevre syndrome (PLS) in an Egyptian patient clinically diagnosed as PLS and to characterize the clinical features. Patient and methods A 5 year and 3 month old girl from the outpatient’s Oro-Dental Genetics clinic – National Research Center presented with the typical clinical findings of Papillon Lefevre syndrome. Genomic DNA was extracted from peripheral blood samples of the patient, her parents and 20 healthy Egyptian controls using standard procedures. All exons of the CTSC gene were amplified by PCR. Sequence analysis of the patient, her parents and controls was performed for mutation detection. Results Mutation analysis of the CTSC gene in our patient revealed a novel homozygous nonsense mutation in exon 5 (W237X). Her parents revealed the presence of the same mutation in a heterozygous state. The 20 controls showed only the wild type sequence of all exons (no mutation). Conclusion This study reported a novel nonsense mutation in the CTSC gene in an Egyptian patient. This novel nonsense mutation is predicted to produce truncated dipeptidyl-peptidase1 causing PLS phenotype in this patient.

A highly sensitive Photonic Crystal Fiber (PCF) based Surface Plasmon Resonance (SPR) sensor is demonstrated in this paper in the optimized form of circular slotted lattice (CSL) structure. This proposed model performance is numerically scrutinized by using Finite Element Method (FEM) in presence of Perfectly Matched Layer (PML) and Scattering Boundary Condition. Plasmonic material ‘Gold’ which is chemically inert is used in this structure at the outer surface of the slotted area to mitigate fabrication challenge. This model indicates the highest wavelength sensitivity of 16000 nm/RIU using wavelength interrogation, the amplitude sensitivity of 780 RIU−1 by using amplitude interrogation method and the average spectral sensitivity of 6666 nm/RIU, respectively. Besides, this sensor has the potentiality of detecting analytes within Refractive Index (RI) range 1.4 to 1.46 with maximum wavelength resolution of 6.25 × 10−6 RIU and amplitude resolution of 1.28 × 10−6 RIU, respectively and the maximum figure of merits of 400 RIU−1. Moreover, the variation of structural parameters (such as pitch, plasmon layer thickness etc.) and the impact of these changes are also discussed in details. According to the high sensitivity performance, polynomial fit and high Figure of Merit (FOM), this amend structure can be a strong competitor in the field of biosensing.

Having a competitive advantage in infant industry is a vital factor for a country to be efficient in protecting it since usually those infant industries lack the economic scales needed to survive in the market. The protectionism started in eighteenth century in USA as a suggestion for the government to promote the economy. The paper covers several tools are used such as; tariffs and tariff rebates, quotas, governmental subsidies and import-substitution industrialization (ISI). Theoretically it was proved the possibility of achieving the desired results. Then the paper illustrated Malaysia as a case of study that faced several failed stories of providing protection of its automobile infant industry; Proton and Perdua automobile companies were investigated. The results showed that those policies and tools used became a burden on the government budget without being able to compete internationally after decades of protection. Many reasons behind this shock fact such as the tendency of being secure which yield to conceal the truth of being prepared to face the global market competition without protection shields from the government. Also, those countries provided protectionism slowed down economically which led to more obstacles for the protected infant industries to be competitive internationally. Even the efforts of connecting the infant industry with strategic foreign partner have failed miserably in Malaysia. Hence as a recommendations for future attempts of protecting infant industries; the time span of protection should be predetermined and be flexible to adjust simultaneously. In addition, the government should monitor the protected firms to let them disclose the truth. Also, there should be a mix of protection tools used to achieve the optimal goal which is not only to protect the infant domestic industries but to promote them and be internationally competitive and that result can be reflected in growth of the economy.

Desalination brine has high salinity and contains various chemical contaminants and its disposal causes a major concern for desalination around the world. Environmentally friendly and economically feasible methods are essential for sustainable management of desalination brines. On the other hand, adequate supply of various minerals is essential in meeting the increasing demands of growing populations across the world. Land-based mining industries suffer from limited supply of water and energy, depletion of high-grade minerals, environmental issues and various geopolitical conflicts. Although suffers from high cost, low recovery efficiencies and absence of mature technologies, seawater mining offers a potential solution for this. Seawater contains large quantities of various minerals, of which some are rare and expensive in their land-based forms. This can mitigate the mineral scarcity to some extent and reduce the desalinated water price significantly as we get an additional product from desalination. In addition, the environmental impacts associated with the brine discharge can be avoided as well. This paper reviews recent research and technologies on recovering resources from desalination brine. Major thermal and membrane technologies for recovering water, minerals and energy are included. Recent developments in solar ponds, membrane distillation, membrane distillation crystallization, electrodialysis and reverse electrodialysis, chemical precipitation, adsorption/desorption, eutectic freeze crystallization, pressure retarded osmosis and microbial desalination cell etc. are discussed. Although extraction of several materials from desalination brine is technically possible, it is currently expensive and largely restricts the commercialization. Last decade has witnessed an increased academic interest on this topic, however, the number of pilot-scale research has been very limited.

In this paper, an enhanced performance of dual core D-shape photonic crystal fiber utilizing surface plasmon resonance (DD-PCF-SPR) based sensor is numerically proposed and analyzed. The thickness of gold and pitch parameter are optimized to 30 nm and 1.9 um, respectively, which ensures superior sensor performance. It is revealed; at optimized geometrical parameter, the offered sensor displays a supreme wavelength sensitivity of 8000 nm/RIU, wavelength resolution of 1.25 × 10−5 RIU, a supreme amplitude sensitivity of 700 RIU−1, amplitude resolution 1.7857 × 10−5 RIU and a figure of merit (FoM) of 138 RIU−1 due to the analyte refractive index changing from 1.47 RIU to 1.48 RIU. The identifying features are investigated using modal analysis based finite element method (FEM) incorporating COMSOL commercial software. Finally, a relative review is executed comparing amplitude sensitivity, resolution and wavelength sensitivity of the offered sensor with previously reported sensors. As high sensitivity, simple structure, and tremendous linear polynomial characteristics, the offered sensor will be a talented candidate for the detection of various biochemical and biological samples (DNA, mRNA, proteins, sugar). Keywords: Amplitude sensitivity, Dual core-PCF, FoM, Wavelength sensitivity, SPR, Resolution

Currently the fractional order controller becomes much more popular in automation engineering due its flexible tuning technique of control parameters. Moreover, it may not be possible to remove the steady-state errors for every states by using traditional sate feedback integer control approach. Therefore, in this paper a state feedback based fractional order controller is designed for rotary flexible link system. In this scheme, Bode's ideal transfer function is considered as a bench mark to obtain similar transient response of closed-loop system. Based on these idea, trajectory tracking performance of a rotary flexible link is demonstrated through computer simulation program. Effectiveness and usefulness of the proposed fractional control scheme is shown as well.

Thin films of CdTe were prepared with thickness (500, 1000) nm on the glass substrate by vacuum evaporation technique at room temperature then treated different annealing temperatures (373,473,and 573)K for one hour. Results of the Hall Effect and the electrical conductivity of (I-V) characteristics were measured in darkness and light.at different annealing temperature results show that the thin films have ability to manufacture solar cells, and found that the efficient equal to (2.18%) for structure solar cell (Algrid / CdS / CdTe /glass/ Al) and the efficient equal to (1.12%) for structure solar cell (Algrid / CdS / CdTe /Si/ Al) with thick ness of (1000) nm with CdTe thin films at RT.

BACKGROUND Chemical hair straightening becomes popular for managing frizzy hair. Keratin in hair care products can penetrate the cortex of the hair fiber improving the mechanical properties of damaged fibers and promote a surface coating that prevents or decreases water diffusion through the hair fibers. This may have beneficial effects on the hair structure; however, the side effects and safety of this treatment have not yet been completely evaluated. AIMS To evaluate the efficacy and safety of chemical hair straightening application on the hair shaft. SUBJECTS AND METHODS Thirty female subjects older than 15 years with hair curl types III-V were included. They were subjected to full history taking and dermatologic examination of hair and scalp prior to and after application of chemical hair straightener. To detect the presence of transverse fissures, split ends, or possible side effects, the distal 3-5 cm of hair fibers were cut before and after the last step of chemical hair straightener application for light microscopy examination. Three randomly selected samples were examined by transmission electron microscope. RESULTS Chemical hair straightening led to significant decrease in the degree of hair curl and increased hair smoothness and shine. The treated hair fibers showed significant repair of the broken cuticle (P

Exergy Analysis is a viable tool to improve plant efficiency. This chapter focuses on performing exergy analysis of a thermal desalination plant (based on the MSF process) located in Yanbu, Saudi Arabia. Exergy flow rates are calculated and exergy destruction around each of the equipments is estimated. An exergy diagram is prepared to indicate equipment with the highest exergy destruction. The second law of efficiency of the plant is 3.22% and 2.84% at normal and peak loads, respectively. This efficiency is quite low and several measures can be done to improve it by decreasing the inlet exergy to the plant and controlling exergy losses during process operation. This is achieved by considering two variations in MSF designs, that is, once through (MSF-OT) and brine mixing (MSF-M). It is found that the design of MSF-M is a favorable option to minimize exergy loss.

In this study, the first case of partial xanthism in the orangespotted trevally Carangoides bajad (Forsskål, 1775) and the areolate grouper Epinephelus areolatus (Forsskål, 1775) is reported from the Arabian Gulf coasts of Saudi Arabia. In addition, the appearance for the first time of the xanthic phenotype of C. bajad in the area is documented. These anomalies in colour pigmentation were described and compared with specimens of normal pigmentation.