Background: This review aims to discuss various canine retraction techniques using frictionless mechanics. Methods: Between 1930 and February 2022, searches were conducted about various canine retraction techniques using fixed orthodontic appliances in various databases, including PubMed Central, Science Direct, Wiley Online Library, the Cochrane Library, Textbooks, Google Scholar, Research Gate, and manual searching. Results: After removing the duplicate articles, publications that described how to use archwires to perform canine retraction with the archwires were included. Conclusions: The pros and cons of various canine retraction techniques using archwires were thoroughly discussed. T-loop is the preferred spring of all because of it

The primary purpose of this paper is to introduce the, 2- coprobabilistic normed space, coprobabilistic dual space of 2- coprobabilistic normed space and give some facts that are related of them

Experimental investigation of the influence of inserting the metal foam to the solar chimney to induce natural ventilation are described and analyzed in this work. To carry out the experimental test, two identical solar chimneys (without insertion of metal foam and with insertion of metal foam) are designed and placed facing south with dimensions of length× width× air gap (2 m× 1 m× 0.2 m). Four incline angles are tested (20^o,30^o,45^o,60^o) for each chimney in Baghdad climate condition (33.3^o latitude, 44.4^o longitude) on October, November, December 2018. The solar chimney performance is investigated by experimentally recording absorber pl

 This work reports the synthesis and characterization of some Co(111), Ni(11), Cu(11), Zn(l 1), Cd(1 1) and Hg(11) chelates of the new benzothia-zolylazo Ligand ( 5-Me-BTAC ) . The compounds were Characterized by IR , electronic spectroscopy, magnetic susceptibility ,elemental analysis and molar conductance measurements . The elemental analysis suggest the formula [ ML2 ] x.nH2O where x=Cl , n=1 for M= Co(111) and x=o , n=o for the remaining metal ions Electronic spectra and magnetic susceptibility data has supported the proposed octahedral geometry of Co(111) Ni(11) and Cu(1 I) Complexes. Conductivity measurements refer to nonionic structure of these Complexes except of Co(111) .

Since the appearance of COVID-19 disease as an epidemic and pandemic disease, many studies are performed to uncover the genetic nature of the newly discovered coronavirus with unique clinical features. The last three human coronavirus outbreaks, SARS-CoV, MERS-CoV and SARS-CoV-2 are caused by Beta-Coronaviruses. Horizontal genetic materials transfer was proven from one coronavirus to the other coronavirus of non-human origin like infectious bronchitis virus (IBV) of avian. Horizontal genetic materials transfer was also from non-corona viruses like astroviruses and equine rhinovirus (ERV-2) or from coronavirus-unrelated viruses, like influenza virus type C. However, SARS-CoV-2 is identical to SARS-CoV and MERS-CoV. Interestingly, Wuhan ci

The preparation and spectral characterization of complexes for Co(II), Ni(II), Cu(II), Cd(II), Zn(II) and Hg(II) ions with new organic heterocyclic azo imidazole dye as ligand 2-[(2`-cyano phenyl) azo ]-4,5-diphenyl imidazole ) (2-CyBAI) were prepared by reacting a dizonium salt solution of 2-cyano aniline with 4,5-diphenyl imidazole in alkaline ethanolic solution .These complexes were characterized spectroscopically by infrared and electronic spectra along with elemental analysis‚ molar conductance and magnetic susceptibility measurements. The data show that the ligand behaves a bidantate and coordinates to the metal ion via nitrogen atom of azo and with imidazole N3 atom. Octahedral environment is suggested for all metal complex

In this study new derivatives of Schiff bases 5-8, 1, 3-oxazepine 9-16 and tetrazoles 17-19 have been synthesized from the new starting material 1 which has synthesized the reaction of one mole of dichloro acetic acid and two moles of thiophenol, the esters 2-3 were synthesized from the reaction of compound 1 with methanol or ethanol respectively in the presence of H2SO4 as catalyst then 2, 2-dithiophenylaceto Hydrazide 4 were synthesized from the reaction of 2 or 3 with hydrazine hydrate 80%, Schiff bases 5-8 were synthesized from the reaction of 4 with appropriate aldehyde or ketone. Treatment of Schiff bases with maleic and phathalic anhydride in dry benzene to give 1, 3-oxazepen derivatives 9-16 and with sodium azide in tetrahydrofuran

SARS-CoV-2 stands for severe acute respiratory syndrome coronavirus 2 which is the causative agent of spreading coronavirus disease 2019 that is known as COVID-19 pandemic, the disease leads to severe acute respiratory illness. Matrix metalloproteinases- 9 (MMP-9) plays several important physiological functions. This enzyme could also be implicated in the "cytokine storm" in some way, which may represent one of the possible scianrios during coronavirus infection, in addition to its role in the mechanism of lung fibrosis on molecular basis.. The tissue inhibitors of metalloproteinase (TIMPs) are well characterized for controlling the activity of MMPs in extracellular matrix remodeling. They also considered as signaling molecules anal

SARS-CoV-2 stands for severe acute respiratory syndrome coronavirus 2 which is the causative agent of spreading coronavirus disease 2019 that is known as COVID-19 pandemic, the disease leads to severe acute respiratory illness. Matrix metalloproteinases- 9 (MMP-9) plays several important physiological functions. This enzyme could also be implicated in the "cytokine storm" in some way, which may represent one of the possible scianrios during coronavirus infection, in addition to its role in the mechanism of lung fibrosis on molecular basis.. The tissue inhibitors of metalloproteinase (TIMPs) are well characterized for controlling the activity of MMPs in extracellular matrix remodeling. They also considered as signaling molecules anal