Doxycycline hyclate is an antibiotic drug with a broad‐spectrum activity against a variety of gram‐positive and gram‐negative bacteria and is frequently used as a pharmacological agent and as an effector molecule in an inducible gene expression system. A sensitive, reliable and fast spectrophotometric method for the determination of doxycycline hyclate in pure and pharmaceutical formulations has been developed using flow injection analysis (FIA) and batch procedures. The proposed method is based on the reaction between the chromogenic reagent (V4+) and doxycycline hyclate in a neutral medium, resulting in the formation of a yellow compound that shows maximum absorbance at 396 nm. In a batch procedure, the proposed method was validated over the concentration range of 1.0–80 μg mL−1 with a sampling frequency of 30/h, and commercial pharmaceutical samples were successfully determined. The proposed method was successfully adapted with an FIA system where the peak heights are proportionally connected to doxycycline hyclate over the concentration range of 25–400 μg mL−1 with a sampling frequency of 50/h. The limits of detection (LOD) and quantification (LOQ) were 0.9 and 10.44 μg mL−1 and 3.01 and 34.81 μg mL−1 for batch and FIA respectively. The samples were submitted to an HPLC analysis, and the outcomes demonstrated excellent agreement with the suggested procedures. The adopted FIA procedure allows fast monitoring of doxycycline hyclate in pharmaceutical formulations and it can be used for quality control purposes during the production processes of doxycycline hyclate.
Background: evaluate the effects of three different intracoronal bleaching agents on the shear bond strengths (SBS) and failure site of stainless steel and monocrystalline (sapphire) orthodontic brackets bonded to endodontically treated teeth using light cured orthodontic adhesive in vitro. Materials and methods: Eighty extracted sound human upper first premolars were selected, endondontically treated and randomly divided equally (according to the type of the brackets used) into two main groups (n = 40 per group). Each main group were subdivided (according to the bleaching agent used) into four subgroups 10 teeth each; as following : control (un bleached) group, hydrogen peroxide group (Hp) 35%, carbamide peroxide group (CP) 37% group and s
... Show MoreBackground: The frontal sinus area can be used as a diagnostic aid to recognize mouth breather subjects. The aims of this study were to determine the gender difference in each group, to compare the frontal sinus area between mouth breather and nasal breather group, and to verify the presence of correlation between the frontal sinus area and the cephalometric skeletal measurements used in this study. Materials and Methods: Cephalometric radiographs were taken for 60 adults (30 mouth breathers and 30 nasal breathers) age range (18-25), for each group 15 males and 15 females, in the orthodontic clinic in the college of Dentistry at Baghdad University. The control group (nasal breather) with skeletal class I and ANB angle ranged between 2-4º,
... Show MoreThe aim of the research is to identify the reality of strategic planning in the National Insurance Company and its importance in building institutional work and to identify the requirements that enable this company to successfully implement strategic planning and the obstacles that limit its application and then achieve the marketing objectives of this company. This study started from the fact that there is a problem represented by the main question that was stated.  
... Show MoreABSTRACT Background: Polycystic ovary syndrome (PCOS) is one of the most common endocrine disorders affecting women in their reproductive age.It is characterized by anovulation or oligo-ovulation and hyperandrogensim.Androgen excess is the central defect in polycystic ovary syndrome. It is a complex disorder affects general health in addition to oral health.This study aimed to assess the gingival health status among a group of women with polycystic ovary syndrome as well as to estimate the levels of salivaryfree testosterone in unstimulated saliva in relation to gingival health condition. Materials and methods: Sixty two women with an age range 20-25 years old and with a body mass index range18.5-24.9 (normal weight) were included in this s
... Show MoreIn this paper, the effect of wear in the fluid film journal bearings on the dynamic stability of rotor bearing system has been studied depending on the development of new analytical equations for motion, instability threshold speed and steady state harmonic response for rotor with offset disc supported by worn journal bearings. Finite element method had been used for modeling the rotor bearing system. The analytical model is verified by comparing its results with that obtained numerically for a rotor supported on the short bearings. The analytical and numerical results showed good agreement with about 8.5% percentage error in the value of critical speed and about 3.5% percentage error in the value of harmonic response. T
... Show MoreRecently a large number of extensive studies have amassed that describe the removal of dyes from water and wastewater using natural adsorbents and modified materials. Methyl orange dye is found in wastewater streams from various industries that include textiles, plastics, printing and paper among other sources. This article reviews methyl orange adsorption onto natural and modified materials. Despite many techniques available, adsorption stands out for efficient water and wastewater treatment for its ease of operation, flexibility and large-scale removal of colorants. It also has a significant potential for regeneration recovery and recycling of adsorbents in comparison to other water treatment methods. The adsorbents described herein were
... Show MoreThe aim of this research is to employ starch as a stabilizing and reducing agent in the production of CdS nanoparticles with less environmental risk, easy scaling, stability, economical feasibility, and suitability for large-scale production. Nanoparticles of CdS have been successfully produced by employing starch as a reducing agent in a simple green synthesis technique and then doped with Sn in certain proportions (1%, 2%, 3%, 4%, and 5%).According to the XRD data, the samples were crystallized in a hexagonal pattern, because the average crystal size of pure CdS is 5.6nm and fluctuates in response to the changes in doping concentration 1, 2, 3, 4, 5 %wt Sn, to become 4.8, 3.9, 11.5, 13.1, 9.3 nm respectively. An increase in crystal
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