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The infrastructures are one of the basic elements which reflect nation’sdevelopment; therefore infrastructures are the main concern for all of the Officialsresponsible for development and maintenance of infrastructures. Preceding from thisfact the main goal of the researcher is to build a management system, base on siteinvestigation for pavement plants in several projects, to study their productivity andtrying to improve them.After the completion of data collection for all plants which were used for roadpavements, and process these data, several factors were found which affect theirproductivity.Based on the above, many suggestions were made, that will rise the productivity ofthese plants such as systematic planning, determine the requirements for the tracks thatis used, types and number of rollers and finishers, number of compacting, speed offinisher, and gang size. All these factors may insure a good execution for the work, andalso the construction of height production asphalt patching plants, maintenance,monitoring, daily tracking, training courses for the staff, provision of spare parts.An equation is determined for the optimum number of tracks, and also anotherequation for daily productivity per ton for the finisher is determined.Idle time for the finisher is determined, from the collected data, and from thefinisher speed which was estimated in the finisher manual, and the asphalt layerthickness and density, equals to (18%) in the branches and (22%) in the main roads.The researcher is also determined a computer program for calculating the finisherproductivity depending on the surrounding environments.

In the present study, epidemiological survey and molecular characterization of hepatitis A virus during an outbreak in five Tunisian childcare centers in El-Mahres during October and November 2006 were carried out. Five well-water and five drinking water samples were included in the present study. Serological investigation and molecular characterization were carried out. All patients were IgM seropositive and the viral genome was detected in all clinical and well-water samples whereas it was not detected in drinking water from the five childcare centers. Sequence analysis showed that all Tunisian strains belong to sub-genotype IA. The genetic profile of the VP1/2A junction showed that the outbreak isolates underwent an amino acid substitution which was absent in virus's strains detected previously in Tunisia. Further studies need to be conducted to evaluate the emergence of the virus's strains in clinical and water samples and more epidemiological data need to be collected about the risk factors which may contribute to acute hepatitis.

Porcine epidemic diarrhea virus (PEDV), transmissible gastroenteritis virus (TGEV), and porcine group A rotavirus (PRV-A) are major viruses causing enteric diseases of piglets. A multiplex nested reverse transcription polymerase chain reaction (multiplex nested RT-PCR) was developed for the detection of these viruses in field samples from piglets with diarrhea. A mixture of (1) three external pairs of primers, yielding in the amplification step two different amplicons with sizes of 950 bp and 317 bp and (2) three pairs of internal primers in a second round of PCR (nested PCR), yielding two different amplicons with sizes of 792 bp and 208 bp for TGEV and porcine PRV-A, respectively. The genome of PEDV was not detected after the amplification step but it was detected in the second round of PCR, yielding amplicon with size of 291 bp. Multiplex nested RT-PCR can detect TGEV, PRV-A, and PEDV up to concentration 10(2) TCID(50)/mL, 10(1) TCID(50)/mL, and 27.2 microg/microl of RNA, respectively. A total of 175 field samples were collected from swine with diarrhea from January 2005 until July 2007. The samples were tested for the presence of three viruses by a multiplex nested RT-PCR. Dual infections with PEDV and PRV-A were identified in seven specimens (4%) (n = 6). Twenty-one (25%) infections were caused by PEDV and thirty-four infections (41%) were caused by PRV-A. The genome of TGEV was not detected in any of these field samples, however TGEV was detected in piglets infected experimentally. The multiplex nested RT-PCR is rapid, sensitive, and a cost-effective detection method for the detection of porcine enteric viruses., (Copyright 2010 Elsevier B.V. All rights reserved.)