Abstract:
Background: Tuberculin skin test (TST) is a readily available test for the diagnosis of latent tuberculosis infection (LTBI). This study was designed to evaluate LTBI in low-risk children aged 1-15 years.Methods: This cross-sectional study was performed in Shiraz, Iran, over six months during 2009. Totally, 1289 boys and girls were selected by stratified multistage random sampling from four municipality areas before allocating them to 15 groups. Inclusion criteria included age 1-15 years, documented history of BCG vaccination at birth, Iranian nationality and a healthy state of being. Children with acute febrile diseases, immunosuppression, on medication and immigrants were excluded. We considered a TST ≥ 10 mm of induration as positive.Results: The prevalence of LTBI in 1-15 years old children was 4.5%. The percentage was 3.5% in 1-5 year old, 4.1% in 6-10 year old and 5.7% in 11-15 year old children. The highest rate of infection was 9.8% in 15 year olds and the lowest was 2.2% in 3-year old children. Gender had no effect on LTBI rate. There is no significant difference of LTBI prevalence between four municipality areas.Conclusion: The prevalence of LTBI in this study was lower in comparison with other studies performed in Iran. Positive predictive value of TST decreases in low endemic areas for tuberculosis, especially in low-risk groups; therefore, most positive results are false-positive created by nonspecific reactions and infection with environmental mycobacteria. Hence, there is a need for new diagnostic tools that are easy and cost-effective.

Abstract:
Background and aims. Autogenous onlay bone grafting is a common procedure for alveolar ridge augmentation. It has been suggested that the amount of healed bone after this technique would be significantly less than the initial quantity. The aim of this study was to determine the relationship between the various parameters influencing the outcome of ridge augmentation procedures. Materials and methods. Thirty-two patients, 17 males and 15 females (mean age 40 ± 8.66), requiring lateral ridge augmentation in the anterior maxilla were recruited. Bone grafts obtained from either the mandibular ramus or symphysis were grafted on the recipient site and the buccolingual dimensions of the edentulous ridge before and six months after the procedure were measured and the difference between them was considered as ridge augmentation (RA). Parameters including graft thickness (GT), graft area (GA) and donor site (DS) were also recorded. Results. Onlay bone grafts, taken from mandibular and symphysis areas, significantly increased the buccolingual dimension of the alveolar ridge (mean 1.98 ± 1.22 mm, p < 0.001). However, the mean RA by symphysis grafts was significantly greater than ramus grafts (2.49 mm vs. 1.48 mm). There was also a significant correlation between graft thickness, surface area and the amount of bone augmentation. Conclusion. Symphysis area provides thicker and larger grafts, which may result in a better clinical outcome in alveolar ridge augmentation.

Abstract:
Let $A$ and $B$ be Banach algebras and let $T$ be an algebra homomorphism from $B$ into $A$. The Cartesian product space $A\times B$ by $T$- Lau product and $\ell^{1}$- norm becomes a Banach algebra $A\times_{T}B$. We investigate the notions such as injectivity, projectivity and flatness for the Banach algebra $A\times_{T}B$. We also characterize Hochschild cohomology for the Banach algebra $A\times_{T}B$.

Abstract:
Let T be a homomorphism from a Banach algebra B to a Banach algebra A.The Cartesian product space A * B with T-Lau multiplication and l^1-norm becomes a new Banach algebra A *_T B. We investigate the notions such as approximate amenability, pseudo amenability, phi-pseudo amenability,phi-biflatness and phi-biprojectivity for Banach algebra A *_T B. We also present an example to show that approximate amenability of A and B is not stable for A *_T B. Finally we characterize the double centralizer algebra of A *_T B and present an application of this characterization.

Abstract:
In this paper, we investigate the notion of approximate biprojectivity for semigroup algebras and for some Banach algebras related to semigroup algebras. We show that $\ell^{1}(S)$ is approximately biprojective if and only if $\ell^{1}(S)$ is biprojective, provided that $S$ is a uniformly locally finite inverse semigroup. Also for a Clifford semigroup $S$, we show that approximate biprojectivity $\ell^{1}(S)^{**}$ gives pseudo amenability of $\ell^{1}(S)$. We give a class of Banach algebras related to semigroup algebras which is not approximately biprojective.

Abstract:
In this paper we are going to investigate the approximate biprojectivity and the $\phi$-biflatness of some Banach algebras related to the locally compact groups. We show that a Segal algebra $S(G)$ is approximate biprojective if and only if $G$ is compact. Also for a continuous weight $w\geq 1$, we show that $L^{1}(G,w)$ is a approximate biprojective if and only if $G$ is compact. We study $\phi$-biflatness of some Banach algebras, where $\phi:A\rightarrow \mathbb{C}$ is a multiplicative linear functional. We show that if $S(G)$ is $\phi$-biflat, then $G$ is amenable group. Also we show that the $\phi$-biflatness of $L^{1}(G)^{**}$ implies the amenability of $G$.

Abstract:
In this paper, we introduce a new notion of biprojectivity, called Connes-biprojective, for dual Banach algebras. We study the relation between this new notion to Connes-amenability and we show that, for a given dual Banach algebra $ \mathcal{A} $, it is Connes-amenable if and only if $ \mathcal{A} $ is Connes-biprojective and has a bounded approximate identity. Also, for an Arens regular Banach algebra $ \mathcal{A} $, we show that if $ \mathcal{A} $ is biprojective, then the dual Banach algebra $ \mathcal{A} ^{**} $ is Connes-biprojective.

Abstract:
For a Banach algebra $ \mathcal{A} $, we introduce various approximate virtual diagonals such as approximate WAP-virtual diagonal and approximate virtual diagonal. For the enveloping dual Banach algebra $ F(\mathcal{A}) $ of $ \mathcal{A} $, we show that $ F(\mathcal{A}) $ is approximately Connes-amenable if and only if $ \mathcal{A} $ has an approximate WAP-virtual diagonal. Further, for a discrete group $ G $, we show that if the group algebra $ \ell^1(G) $ has an approximate WAP-virtual diagonal, then it has an approximate virtual diagonal.

Abstract:
In this paper, we investigate ?-homological properties for Beurling algebras, where ? is a character on those Banach algebras. We show that L1(G;w) is ?0-biprojective if and only if G is compact, where ?0 is the augmentation character. Also we show that M(G;w) is ?i0 0 -biprojective if and only if G is a compact group, where ?i0 0 is an extension of augmentation character to M(G;w). We de?ne the notion of character-projective Banach A-bimodules and also ?-split and ?-admissible triples. We show that L1(G) is amenable if and only if some particular ?-admissible triples of Banach L1(G)-bimodules are ?-split triples.