Construction and characterisation of attenuated derivatives of Pasteurella multocida: serotype B:2 strains

The project was concerned with the construction of defined attenuated derivatives of P. multocida serotype B:2 strains, causative agents of haemorrhagic septicaemia, and attempts were made to construct defined mutations in genes such as aroA, cya, and galE loci that have been used to induce attenuation in other bacterial strains. Mutants defective in the aroA gene were constructed by allelic exchange of the locus in the chromosome of the wild-type strains with a cloned aroA gene interrupted with a cassette encoding kanamycin resistance (KmR). The aroA defective strains were confirmed by PCR, Southern blotting, lack of growth on minimal medium and by enzyme assay. KmR inactivated aroA mutants JRMT1 and JRMT2 strains derived from P. multocida 85020 and Quetta strains, respectively, were highly attenuated in a mouse model, with an LD50 108 C.F.U./mouse after injection intraperitoneally (i.p.). In contrast, the wild-type strains had LD50 <50 C.F.U./mouse by this route. Vaccination once by the i.p. route or twice by the i.n. route with these aroA mutants gave complete protection to the mice against subsequent challenge i.p. with 10,000 LD50 of the homologous wild-type strain or 1000 LD50 of the heterologous wild-type strain. Vaccination with these by the s.c. route was not protective. When high doses of the attenuated strains were inoculated by the i.p. or i.n. routes, there was some spread to the internal organs but the organisms were cleared by 24 and 72 hrs respectively. In contrast, the wild-type parent strains spread rapidly and multiplied in high numbers and killed the mice by 24 and 96 hrs respectively

Comparison of Iris Fixated and Scleral Fixated intra Ocular Lens for Correction of Aphakia in Traumatic Cataract with no Proper Capsular Support

Purpose: To compare visual outcomes and complications of iris fixated and scleral fixated intra ocular lens (IOL) implantation in patients suffering from traumatic cataract with no proper capsular support.Patients and Methods: This prospective interventional study was performed in Farabi Eye Hospital, Tehran, Iran, between May 2015 and May 2016. Twenty five patients with traumatic cataract and no proper capsular support for IOL implantation in the bag or sulcus were included and randomly underwent either iris fixated or sulcus fixated IOL implantation. Follow up visits were performed one day, one week, four weeks, three months and six months after surgery. In each visit visual acuity, intra ocular pressure, placement of IOL and anterior chamber reaction were studied. Results: Thirteen eyes of 13 patients underwent iris fixation and 12 eyes of 12 patients underwent scleral fixation of IOL. The average patient age at presentation was 29.12 ± 16.32. In the follow up visit one week after IOL fixation three patients in each group had significant anterior chamber inflammation. There was no statistically significant difference between the two groups regarding the number of patients with elevated IOP (P = 0.96), dislocated IOL (P = 0.480) and complications such as wound dehiscence and iridocorneal adhesion. Also no statistically significant difference regarding the mean BCVA three months after surgery was observed (P = 0.55).Conclusion: We did not observe any significant difference in outcome of iris and scleral fixation of IOL in traumatic eye injuries with no effective capsular support.&nbsp

Non-overshooting PD and PID controllers design

This paper involves the design of non-overshooting PD and PID controllers for some special plants. The PID controller parameters are determined to reach a stable closed-loop system with monotonically decreasing frequency response. Thus specific regions in the controller parameters space are obtained. Gain crossover frequency and phase isodamping property are employed to choose an appropriate solution among the obtained solutions. The performance of the proposed PD and PID controllers in position and velocity control of a laboratory DC servomechanism system is investigated through experimental tests

Real-Time Evaluation of Stimulation and Diversion in Horizontal Wells

Optimum fluid placement is crucial for successful acid stimulation treatments of long horizontal wells where there is a broad variation of reservoir properties along the wellbore. Various methods have been developed and applied in the field to determine acid placement and the effectiveness of diversion process, but determining the injection profile during a course of matrix acidizing still remains as a challenge. Recently distributed temperature sensing technology (DTS) has enabled us to observe dynamic temperature profiles along a horizontal wellbore during acid treatments. Quantitative interpretation of dynamic temperature data can provide us with an invaluable tool to assess the effectiveness of the treatment as well as optimize the treatment through on-the-fly modification of the treatment parameters such as volume, injection rate and diversion method. In this study we first discuss how fluid placement can be quantified using dynamic temperature data. A mathematical model has been developed to simulate the temperature behavior along horizontal wellbores during and shortly after acid treatments. This model couples a wellbore and a near-wellbore thermal model considering the effect of both mass and heat transfer between the wellbore and the formation. The model accounts for all significant thermal processes involved during a treatment, including heat of reaction, conduction, convection. Then a fast and reliable inversion procedure is used to interpret the acid distribution profiles from the measured temperature profiles. We extend the real-time monitoring and evaluation of the acid stimulation treatment in horizontal wells to calculate the evolving skin factor as a function of time and location along the wellbore. As the skin factor is a reflection of the injectivity, it will indicate directly if the acid stimulation is effective and if diversion is successful. The approach to monitor the evolving skin along the lateral is to use a proper pressure transient model to calculate skin factor by integrating the inversion results of the temperature data (acid injection profile) with either surface or bottomhole injection pressure. This method can help engineers to optimize an acid stimulation in the field

A Comprehensive Investigation to Identify Working Memory Components Utilizing Thematic Analysis Technique: A Qualitative Research

Background: Working memory (WM) is commonly known as a mediator between short-term and long-term memory. However, WM as well is a data processor and manipulator in charge of a considerable portion of our cognitive abilities. Due to the recently grasped significance of further investigations of WM, this study was conducted aiming to identify the entire WM components present in the current literature utilizing qualitative thematic analysis.Methods: Stirling’s novel method of qualitative inductive thematic analysis was applied to extract the entire components of WM from the current literature up to 2018.Results: Our results yielded 57 basic concepts (themes) related to WM out of 1099 concepts, which was integrated into 18 organizing concepts that altogether comprise the global notion of WM. Statistical validation was conducted through expert confirmation and content validity index (CVI) calculation (0.88). Moreover, the Holsti coefficient was 0.60 that indicates relatively appropriate reliability.Conclusion: Considering the growing interest in studying WM components, conducting an integrative research aiming to thoroughly clarify these components was required. Herein, through applying the novel technique of thematic analysis, we have developed a comprehensive theme network designed to facilitate future studies on WM

Morphological plasticity of Nemoura Cinerea (Arthropoda, Nemouridae) as a biological indicator for aquatic systems

Macrobenthos are indicators of the physical and chemical changes in aquatic ecosystems. In this research, the diversity of macrobenthos communities in the Ortkand River, Iran, was investigated during four consecutive seasons using the Shannon-Weiner, EPT richness indices, and the Hilsenhoff index for water quality at four sampling stations. In addition, sampling of Nemoura cinerea (Arthropoda, Nemouridae) was done to compare morphological differences between specimens from two upstream and downstream sites using a geometric morphometric approach. The physicochemical parameters of water were also recorded. The entry of fish farm wastewater significantly affects biotic and abiotic environmental factors according to the Shannon-Weiner and Hilsenhoff indices. The results showed a significant positive correlation between DO and Shannon-Wiener index, TDS and the Hilsenhoff index, and DO and EPT richness index. A significant negative correlation was observed between BOD and the Shannon-Wiener index, DO and Hilsenhoff index, and between BOD and EPT richness index. Geometric morphometrics analyses revealed that the two groups differed mainly in pronotum and metanotum morphology. According to the results, monitoring of macrobenthos can help assess rivers’ water quality, and N. cinerea can be a proper bioindicator