Clinical Investigation of 940 nm Diode Laser Power Bleaching: An In Vivo Study

Introduction: The increased demand by patient to whiten their teeth in short time had made in-office bleaching procedure the common one. The accompanying tooth sensitivity remains an important factor affecting patients physically and psychologically. The aim of this in vivo study was to observe the effectiveness of 940 nm diode laser in combination with bleaching gel by analyzing tooth sensitivity and colour change.Methods: Fourteen patients treated by laser-assisted bleaching using diode laser at 940 nm and bleaching gel containing 38% hydrogen peroxide. Tooth sensitivity recorded during and after treatment at 6 hours and 1 day using visual analogue scale (VAS). Tooth shade had recorded before and after bleaching using Vita classical brightness scale.Results: Patients whom did not experienced pain during and after the treatment were 78.60% and 92.90%, respectively. Tooth brightness change after treatment was statistically different (P = 0.001).Conclusion: Diode laser of 940 nm is an effective adjunctive tool for reducing tooth sensitivity originated from high concentration H2O2 bleaching gel

Ecological study of two gastropods species Melanoides turbuculata and Melanopsis preaemorsa from Euphrates river - Basrah, Iraq

Biological and taxonomic studies of snails in the waters of Iraq's desert have been enhanced through seasonal recording of them, and it is one of the means to follow their distribution and determine the density. Aiming to determine occurrence and density of two snails Melanoides tuberculata and  Melanopsi preaemorsa, in two stations at the Euphrates river-Basrah, Governorate, in Al-Madina and Al-Qurna. Three replicates within each station were chosen for sample collection of these two species using the quadrate (25 × 25) cm. Many environmental factors including temperature, salinity, pH, dissolved oxygen (DO), and organic material in sediment were measured, 5,330 samples were obtained from the stations. The highest annual density was recorded by snail M. turbuculata with 2,745 and 1,072 ind/m² in two stations respectively, while M. preaemorsa with 912 and 601 ind/m² in (St.1 and 2), respectively. The densities of snail M. turbuculata from 480 ind./m2, June 2019 at (St. 1) to 57 ind./m2 in December 2019. And in (St. 2) from 256 ind./m2 in May 2019 to 0 ind./m2 in August - December 2019. While snail species M. preaemorsa (Linnaeus, 1758) in (St. 1) from 128 ind./m2 in June and July to 0 ind./m2 in January-February, November-December 2019 and in (St. 2) from 144 ind./m2 in April to 0 ind./m2 in August-December 2019. The statistical analysis found significant differences in DO, temperatures, and snail density in two stations. This is the first study in the region on these two species in particular, and their abundance

First record of Octopus vulgaris (Cuvier, 1797) (Octopodidae) in the Iraqi coastal waters, NW Arabian Gulf

The present study identifies one species of the genus Octopus in the order: Octopoda (Cephalopoda: Mollusca), recorded forthe first time in the Iraqi coastal waters and Arabian-Persian Gulf. The study extended from January 2019 to December of thesame year. The Octopus specimens were seasonally obtained from the fishing trawlers operating in the Iraqi coastal waters inthe South of Al- Fao District, Basrah- Iraq, NW Arabian Gulf. The Octopus was identified as O. vulgaris in Iraqi coastal watersdepending on morphological features. The habitats of living specimens are briefly described. Some observations were reported on the occurrence of this species and the measurement of some environmental factors. The species was identified up to spe-cies level using standard literature. This species looks similar morphologically to the species which is already identified from the other areas around the world. The present study records significant expansion in the distribution range of this species

High-speed photographic studies of blast wave impact phenomena

An exploding wire technique (EWT) is described, which provides high rates of loading by producing cylindrical blast waves of high reflection pressure with short duration. These waves have been used for internal impact of hollow polymeric cylindrical specimens. The EWT overcomes the small size restrictions of other high strain rate testing methods like the Split-Hopkinson pressure bar technique and drop weight. [Continues.

The Study of annual shrimp stocks in Masshab (Al-Hammar Marsh), Basrah, Southern Iraq

The catch was identified and included two species of shrimp in the waters of the Masshab near Al – Hammar Marsh, Basra, Iraq. During the study period, some of the following environmental factors were recorded, Temperatures are between 20 to 30 ° C; Salinity (‰) between 1.5 to 4.9; The pH value is between 6.9 to 8.0; Turbidity (NTU) between 18.4 to 21.5. The total catch from shrimp, Metapenaeus affinis, and Macrobrachium nipponense was 373,35 ± 12.03 per hour per year, and the monthly catch rate for shrimp was 33.11 ± 12.03 kg per hour per month. The peak of fishing during the summer months was the highest in July, with fishing reaching 47.200 kg per hour during July, while the lowest quantities of fishing were in winter during the January month at 12 kg per hour. The overall catch rate for M. affinis was 124 ± 10.58 kg per hour per year, while the total catch rate for M. nipponense was 241± 13.33 kg per hour per year. The female sex ratio was higher than that of males in two species, M. affinis of males was 21.67, and females were 78.33, while in M. nipponense males were 14.6 to 83.25. And female of M. nipponense bearing of eggs 28.62 ± 34,21 during the year. While non-eggs carriers 71.38 ± 34.21. The period in which females were observed carrying-eggs was determined during the summer months from April to July. The highest  percentage of egg-carrying was in July at 88.40% and at January, 11.6%. The longest. M. affinis was 10 cm and the smallest was1 cm, the longest, while M. nipponense and 9 cm and the smallest was 1 cm

Control of Gaseous Pollution via the Leaves of Non-Edible Trees

The accelerated increase of the use of various transportation means, industrial machinery and other power consuming technologies has led to tremendous degradation of outdoor air quality all around the world. Green solution was tested here as an innovative gas control mean via non edible Myrtus communis green leaves as natural sorption media. Statistical analyses was applied in order to examine the correlation between various parameters of this study. The tests of  gas records around the tree that was targeted by  a gas stream of 5 KW power generator  have demonstrated an excellent gas control role of the green leaves, with average efficiencies of about 75% and 82% for the removal of Nitrogen Dioxide and Carbon Monoxide, respectively. An interesting finding of this research was that the sorption role of green leaves has promoted their sizes and Chlorophyll Content Index. Keywords: Chlorophyll Index, Green gas control, Myrtus communis, Leaf size, Outdoor pollution, Sorption

Strain rate behaviour of thermoplastic polymers

Polymers are increasingly used in structures that have to withstand impact conditions. This thesis describes an investigation of strain rate properties at room temperature of four engineering polymers; polyethylene (high density, HDPE and ultra high molecular weight, UHMWPE), nylatron and polyetheretherketone (PEEK 150g). A split Hopkinson pressure bar (SHPB) system was used to study the response of these polymers in compression tests at high strain rates up to 10' S-1. Stress equilibrium in SHPB samples was studied theoretically by examining multiple reflection effects during the initial elastic loading of the polymers; this study proved very useful in the analysis of SHPB tests. To cover a wide range of strain rate, compression studies were also made at low strain rates (10-3 _10-2 S-1) using a Hounsfield screw machine. Viscoelastic models have been applied to these results. These models fit quite well with the experimental results of HDPE, UHMWPE, and nylatron, but not to the PEEK due to the yield drop in the stress - strain curves, especially at high strain rates. An exploding wire technique was used as an axial impulsive loading system for hollow cylindrical samples. An image converter camera at framing intervals of 21ls or 10 Ils recorded the radial expansion of the cylinder. The expanding cylinder was used as a driving system for a new technique called the freely expanding ring method, which was used to obtain the stress - strain behaviour of polymeric thin rings placed as a sliding fit on the cylinder. This method produced very high tensile strain rates up to fracture (> 10' S-1). Comparisons have been made between results obtained from the quasi-static, SHPB, and expanding ring tests. The freely expanding ring and SHPB results were in good agreement indicating similar tensile and compressive high strain rate behaviour. The mechanical properties of the above polymers are strongly dependent on strain rate. The Young's modulus and the flow stress increase with increasing strain rate. Nylatron showed high strain rate strain softening at high strain, this was due to the high temperature rise during loading, when the transition temperature (Tg) of the material (50 QC) was exceeded. However, the other materials showed continuous hardening behaviour. Plots of the flow stress at 5% and 10% strain vs log strain rate showed a linear increase up to a strain rate of about 103 S-1. Above 103 s-1, the stress rose more rapidly, but then showed significant drops for nylatron and PEEK. These drops in stress are probably due to both micro crack initiation in the sample and also high temperatures around the crack tips

Control Pepper Fusarium Wilting by biocontrol agent Trichoderma harzianum and Chelated Iron Fe-EDDHA

الفلفل الحلو من المحاصيل الاقتصادية المهمة، يعد مرض الذبول المتسبب عن الفطر Fusarium oxysporum f. sp. capsici من الامراض المهمة التي تؤثر على الفلفل. تم الحصول على اربع عزلات منF. oxysporum   (Fo3، Fo6، Fo7 و Fo8) من نباتات فلفل مصابة جمعت من حقول مختلفة في محافظة بغداد. اظهرت العزلة Fo6 امراضية عالية على بذور الفلفل، تم اختبار Trichoderma harzianum (Th) ضد  F. oxysporum f. sp. capsici في المختبر واظهر نسبة تثبيط عالية ضد العزلة Fo6، الحديد المخلبي بتركيز 0.5٪ قلل من النمو الشعاعي للعزلة Fo6 بينما لم يؤثر على نمو Th. في تجربة الاصص، اظهرت المعاملة Fo6+Th+Fe خفضاً معنوياً في نسبة وشدة الاصابة بمرض الذبول وتعفن الجذور قياساً مع المقارنة. كما حققت المعاملة Th+Fe زيادة عالية المعنوية في الوزن الطري والجاف للمجموعين الجذري والخضري اذ بلغت 63.36، 130.56، 4.55 و 10.26غم على الترتيب قياساً بالمقارنة (من دون الممرض) التي سجلت 11.10، 54.83، 1.30 و 3.70غم على الترتيب. واوضحت نتائج تجربة البيت البلاستيكي ان المعاملة Fo6+Th+Fe خفضت نسبة وشدة الاصابة بالعزلة Fo6 اذ بلغت 3.33 و 1.67% على الترتيب واعطت المعاملة Th+Fe ارتفاع في محتوى الكلوروفيل الكلي الذي بلغ 104 سباد قياساً بالمقارنة التي سجلت 70.4 سباد.  Sweet pepper (Capsicum annuum L.) is an economically important vegetable crop. Wilt disease caused by Fusarium oxysporum f. sp. capsici is a specific pathogen that affects the pepper. Four isolates of F. oxysporum f. sp. capsici Fo3, Fo6, Fo7 and Fo8 were obtained from diseased pepper plants that were collected from different pepper fields in Baghdad. Fo6 isolate that has high pathogenicity to pepper seeds, Trichoderma harzianum (Th) was tested in vitro against F. oxysporum f. sp. capsici showed a high inhibition rate for the isolate Fo6, the concentration of chelated iron Fe-EDDHA 0.5% reduced the radial growth of Fo6 while did not affect the growth of Th. In pots experiment, the treatment Fo6+Th+Fe showed a significant reduction in the incidence and severity of root rot and wilt diseases. The treatment Th+Fe achieved a highly significant increase in fresh and dry root and vegetative weight 63.36, 130.56, 4.55 and 10.26g respectively, compared with control (without pathogenic) reaching 11.10, 54.83, 1.30 and 3.70g respectively. Moreover, in greenhouse the treatment Fo6+Th+Fe has reduced the incidence and severity of disease 3.33 and 1.67% respectively, and the treatment Th+Fe gave an increase in the total chlorophyll content 104 SPAD compared with the control 70.4 SPAD

Aerodynamic Characteristics Improving of S809 Airfoil in Wind Turbine with Microtab

In present work numerical two dimensions, steady, incompressible, turbulent flow past S809 wind turbine airfoil with microtab at 95% of chord length of leading edge in lower surface is analyzed by Fluent (6.2) program for model consists of S809 airfoil without and with microtab at 95% of chord line have height 1.1% and other 2% of chord length undergo to turbulent flow k-. model, the flow has Reynolds number is 106. The results are represented by velocity contour and vector. Aerodynamic coefficients are drawn in graph. The results are showed an increase lift and drag coefficient in existence microtab locate 95% of chord at it's height 1.1% and 2% of chord to range of attack angle (0, 5, 10, 15, 20) degrees. The results compare with experimental data of standard airfoil and existence 1.1% chord length microtab and it is approximately good. Values of lift & drag coefficient are increased for the existence of 1.1% chord length microtab while in case the existence of microtab 2% chord length lift coefficient increased which it's max. increment by 46% while, drag coefficient decreased it's min. increment to be 26% but not full range of attack angle

A study on the feeding of shrimp larvae of Macrobrachium nipponense on algae in vitro

Experiments were carried out for the propagation and rearing of Macrobrachium nipponense and its feeding on algae, with the aim of determining the density, survival, and growth of larvae in vitro. Hatched larvae of zoae were reared at a density of 50 zoea/L with algae mixture: Chlorella vulgaris, Scenedesmus sp., Pediastrium sp., Microctinium sp., Navicula sp., Ulothrix sp., Cyclotella sp., Daitoma sp. at three concentrations of 0.5=A, 1.0=B, 1.5=C x 10⁵ cell/ml, and the survival % rates of zoea larvae were 45.00±5.00, 53.33±7.64, 50.00±5.00 respectively. Then, three densities: 25=A, 50=B, 75=C zoea/L were tested by feeding them with the best concentration of 1.0×10⁵ cell/ml for 10 days, with the result being survival % rates were  50.00±5.00, 51.67±7.64, 31.67±7.64, respectively. After that, stage post-larvae were reared at a density of (50=A,100=B, 150=C) Pl/pond and fed with a concentration of 1.0 x 10⁵ cell/ml of the algae mixture for 28 days, which resulted in survival % rates of 48.33±7.64, 40.00±5.00, 33.33±7.64, and this stage, weight was 50.67±2.08, 50.00±2.00, 40.33±2.52mg respectively. The results of the analysis of survival rates for different densities of zoea larvae found significant differences (P < 0.05) between density C and density of both A and B, of which there were no significant differences (P > 0.05) between them. There were no significant differences (p > 0.05) in the survival rates of zoea in different concentrations of the selected algae. Also, there were no significant differences (p > 0.05) in the survival rates and weight rate of post-larvae when fed on algae (B)