Background: With the increasing demands for adult orthodontics, a growing need arises to bond attachments to porcelain surfaces. Optimal adhesion to porcelain surface should allow orthodontic treatment without bond failure but not jeopardize porcelain integrity after debonding.The present study was carried out to compare the shear bond strength of metal bracket bonded to porcelain surface prepared by two mechanical treatments and by using different etching systems (Hydrofluoric acid 9% and acidulated phosphate fluoride 1.23%). Materials and Methods: The samples were comprised of 60 models (28mm *15mm*28mm) of metal fused to porcelain (feldspathic porcelain). They were divided as the following: group I (control): the porcelain surface left u

The effect of thickness variation on some physical properties of hematite α-Fe2O3 thin films was investigated. An Fe2O3 bulk in the form of pellet was prepared by cold pressing of Fe2O3 powder with subsequent sintering at 800 . Thin films with various thicknesses were obtained on glass substrates by pulsed laser deposition technique. The films properties were characterized by XRD, and FT-IR. The deposited iron oxide thin films showed a single hematite phase with polycrystalline rhombohedral crystal structure .The thickness of films were estimated by using spectrometer to be (185-232) nm. Using Debye Scherrerś formula, the average grain size for the samples was found to be (18-32) nm. Atomic force microscopy indicated that the films had

Background:Wilson’s disease (WD) is an inherited
disorder of copper metabolism that is characterized
by tremendous variation in the clinical presentation.
Objective: To assess demographic distribution,
clinical presentations, diagnostic evaluation, and any
association between clinical presentations and other
studied variables of a sample of Iraqi patients with
WD.
Methods: A descriptive cross sectional study with
analytic elements was conducted during 2011, from
the 1st of February till the 10th of June. The sampling
method was a convenient non-random one, carried
out through consecutive pooling of registered WD
patients. A questionnaire-form paper had been
developed for the process of data col

Dueto their ability to providefood for people, sheep and goats areimportant to the economiesofmanynations.Toxoplasmagondii,orT.gondii,isaprotozoanparasite that often infects sheep. Stillbirth, early embryonic death and resorption, neonatal mortality, fetal death and mummification, and parasite infection are examples of possible negative effects. Theconsequences aremoreseverethe earlier in gestation the infection arises. The stage of pregnancy at which the infection occurs in thesheep and goats is connected with the severity of the illness. T.gondii may infect humansandcarnivorousanimalsvia the meatofinfectedsheepandgoats.Lessthan 4%ofsheep thatareconsistently infected withT.gondiicarrytheparasitevertically to their offspring. The majority o

    This paper is intended to apply data mining techniques for real Iraqi biochemical dataset to discover hidden patterns within tests relationships. It is worth noting that preprocessing steps take remarkable efforts to handle this type of data, since it is pure data set with so many null values reaching a ratio of 94.8%, then it becomes 0% after achieving these steps. However, in order to apply Classification And Regression Tree (CART) algorithm, several tests were assumed as classes, because of the dataset was unlabeled. Which then enabled discovery of patterns of tests relationships, that consequently, extends its impact on patients’ health, since it will assist in determining test values by performing only relevant

Emails have proliferated in our ever-increasing communication, collaboration and
information sharing. Unfortunately, one of the main abuses lacking complete benefits of
this service is email spam (or shortly spam). Spam can easily bewilder system because
of its availability and duplication, deceiving solicitations to obtain private information.
The research community has shown an increasing interest to set up, adapt, maintain and
tune several spam filtering techniques for dealing with emails and identifying spam and
exclude it automatically without the interference of the email user. The contribution of
this paper is twofold. Firstly, to present how spam filtering methodology can be
constructed based on the concep

     The messages are ancient method to exchange information between peoples. It had many ways to send it with some security.

    Encryption and steganography was oldest ways to message security, but there are still many problems in key generation, key distribution, suitable cover image and others. In this paper we present proposed algorithm to exchange security message without any encryption, or image as cover to hidden. Our proposed algorithm depends on two copies of the same collection images set (CIS), one in sender side and other in receiver side which always exchange message between them.

      To send any message text the sender converts message to ASCII c

Student dropout is a problem for both students and universities. However, in the crises that Lebanon is going through, it is becoming a serious financial problem for Lebanese private universities. To try to minimize it, it must be predicted in order to implement the appropriate actions. In this paper, a method to build the appropriate prediction system is presented. First, it generates a data source of predictor variables from student dataset collected from a faculty of economic sciences in Beirut between 2010 and 2020. Then, it will build a prediction model using data classification techniques based on identified predictor variables and validate it. Using open-source software and free cloud environments, a prediction program w

This paper designed a fault tolerance for soft real time distributed system (FTRTDS). This system is designed to be independently on specific mechanisms and facilities of the underlying real time distributed system. It is designed to be distributed on all the computers in the distributed system and controlled by a central unit.

Besides gathering information about a target program spontaneously, it provides information about the target operating system and the target hardware in order to diagnose the fault before occurring, so it can handle the situation before it comes on. And it provides a distributed system with the reactive capability of reconfiguring and reinitializing after the occurrence of a failure.