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Introduction: Previous studies indicated that children, who acquired conversation concept, produce adjectives better than other mental retarded.
Other studies showed that Down syndrome children have lower linguistic abilities than other mental retarded children. The main goal of this research was to study the effects of Down syndrome on production of semantic skills.
Materials and' Methods: This analytic cross-sectional study was conducted on girls who studied in exceptional primary schools of Semnan city.
Samples were chosen systenlaticaly. At first, 38 Down syndrome girls, who were monolingual and with no sign of sensory and motor deficits, were selected.
Then, 37 mental retarded girls (non-Down syndrome), that mental retardation had no specific ethiology, were matched on date of birth, educational level, failuer in previous classes, parent's job and education. These 75 pupils participated in operative tests and those who were able to comprehend the concept of conversation were examined by Raven Colourd Progressive Matrices. At final stage, 30 educable girls were participated in production test.
Results: Our findings showed that:
1. The production of nominal and superlative adjectives were equivalent between two groups, but Down syndromes had lower ability in production of comparatives;
2. The simplisity of adjectives were as fallow: nominal> comparative> superlative, and big-small> tall-short> thick-thief> wide-narrow.
3. There were few samples able to produce superlatives.
Conclusion: This investigation revealed that girls suffering from Down syndrome have lower ability on production of semantic skills.

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Abstract

Background: Prevalence extension of antibiotic resistant bacteria has raised concerns about control of infections especially nosocomial infections. Many attempts have been done to replace antibiotics or limit their use. The use of antimicrobial agents produced by bacteria as antibiotic replacement has been promising in recent years. The goal of this study was to isolate Bacillus strains and evaluate their antimicrobial activity against some standard pathogens and clinical antibiotic resistant strains.

Materials and Methods: In the present study, Bacillus strains were isolated from various resources and identified by 16S rDNA PCR method. Then, the phylogenetic tree of the isolates was constructed and antimicrobial activity of the isolates was investigated against some standard pathogens and clinical antibiotic resistant strains using spotting and well diffusion methods.

Results: Eight Bacillus strains were isolated from 15 different samples. Based on the molecular identification, the isolates were identified as B.pumilus, B.coagulans, B.licheniformis, B.endophitycus and B.amiloliquefaciens. The results showed that isolates have antimicrobial activity against meticilin-resistant Staphylococcus aureus, vancomycin resistant enterococci, Klebsiella, Acinetobacter, Salmonella, Shigella, Listeria, Streptococcus and Escherichia coli.

Conclusion: In this study, isolated Bacillus strains produced antimicrobial agents against pathogens and antibiotic resistant strains and inhibited their growth.