This study was conducted to assess the prevalence of resistance genotypes of extended-spectrum and AmpC β-lactamase producing Escherichia coli and Klebsiella pneumoniae. Out of 632 samples, suspected for E. coli and K. pneumoniae, collected from different units of Pakistan Institute of Medical Sciences, Islamabad, Pakistan, the number of positive samples for E. coli and K. pneumoniae were 593 (93.8 %). Out of these 593 isolates, 61.6% (n=365) were identified as E. coli and 38.4% (n=228) were K. pneumoniae. Common age group for sample isolation was 13-25 years for both E. coli and K. pneumoniae, from which 29.9% of E. coli (n=109) and 27.6% of K. pneumoniae (n=63) were isolated. However, none of the age groups achieved statistical significance. Higher percentage of E. coli was isolated from females as compared to males, while the ratio of K. pneumoniae was higher in male patients (p=0.012). Most of the isolates were recovered from specimens collected from outdoor patients and were mainly from urine samples. ESBL production was detected in 46.20% (n = 274) of the 593 isolates by phenotypic method. Out of total 365 E. coli strains, 49.3% (n = 180) were found to be ESBL producers and 41.2% (n =94) of total 228 K. pneumoniae isolates, were ESBL producers. Statistical analysis indicated that age groups have significant association with the presence of ESBLs (p= 0.007) in E. coli isolates. No significant association was observed in ESBL producing K. pneumoniae with age, gender, sample source or origin. AmpC β-lactamase production was detected in 25.8% (n = 94) of the total 365 E. coli and 20.6% (n =47) of total 228 K. pneumoniae isolates. There was significant association between males (p=0.018) and samples collected from surgical ward (p=0.01) with AmpC positive status in E. coli isolates. No significant association (p=0.88) was found in AmpC producing K. pneumoniae and gender. However, like AmpC producing E. coli, isolation from surgical wards had a statistically significant association with AmpC positive K. pneumoniae (p=0.001). Out of these 593 isolates, 200 samples of the phenotypically confirmed ESBLs or AmpC producers, E. coli and K. pneumoniae, were processed for antibiotic susceptibility analysis and detection of the selected genes. Out of 200, 131 were E. coli and 69 were K. pneumoniae. The highest resistance (90.1%) was observed against sulphamethoxazole, followed by tetracycline (88.5%) and ciprofloxacin (80%) among E. coli isolates. In case of β-lactam antibiotics, high resistance (87.8%) was observed against cefotaxime and amoxicillin/clavulanic acid, followed by cefepime (81.7%) and aztreonam (79.4%). Out of the total 131 E. coli isolates, 100 (76.3%) were found resistant to ceftazidime having an MIC >32μg/ml. Highest resistance was observed in case of amoxicillin/clavulanic acid, in which 117 isolates (89.3%) were resistant, followed by cefotaxime (116, 89.3%). About 45 (34.3%) isolates of E. coli showed resistance to cefoxitin with a maximum range of 256 μg/ml. PCR amplification revealed that CTX-M-1 was the most frequently (77 isolates, 58.7%) detected ESBL gene group, followed by TEM (25 isolates, 19%) and SHV (19 isolates, 14.5%). CTX-M-9 group was observed in only 4 bacterial isolates. Among AmpC β- lactamases, MOX gene was detected in 19 (14.5%) E. coli isolates, CIT in 17 (13%), CMY gene in 7 (5%), EBC gene in 5 (4%), and 2 isolates showed FOX AmpC β-lactamases. A total of 26 different patterns of genes were detected in 112 E. coli isolates, while no candidate gene was found in 19 E. coli isolates. Among K. pneumoniae, higher resistance was observed in case of tetracycline (98.6%), amoxicillin/clavulanic acid (97.1%) and sulphamethoxazole (95.7%). In case of β-lactam antibiotics, cefoxitin was the most successful antibiotic showing resistance to 20 (29%) isolates, followed by ceftazidime and cefepime (69.6%) and aztreonam (75.4%). MIC results revealed that fifty isolates (72.5%) were found resistant to ceftazidime with a maximum range of 512 μg/ml, while 19 (27.5%) were found susceptible. Fifty six (81%) isolates were resistant to cefotaxime and 61 (88.4%) to amoxicillin/clavulanic acid. Cefoxitin was the most successful antibiotic, effective against 47 (68.1%) of the total 69 K. pneumoniae isolates tested CTX-M-1 type ESBLs were detected in 43 (62.3%) isolates, SHV in 9 (13%), TEM in 8 (11.6%) and CTX-M-9 in 2 isolates (3%). Six (9%) isolates showed CIT type AmpC genes while 4 (6%) had CMY, 3 (4%) each FOX and MOX and 2 (3%) had EBC type genes. Eighty genes showed amplification in 69 K. pneumoniae isolates. A total of 18 different patterns of genes were detected in K. pneumoniae in a total of 58 isolates, while in 11 isolates, no gene was detected. Our study showed that both class A and class C β- lactamases contributed to cephalosporin resistance in E. coli and K. pneumoniae, thereby limiting therapeutic options. Co-expression of these enzymes may further hinder the identification of ESBLs, which is a critical step for designing a successful treatment for multidrug-resistant E. coli and K. pneumoniae. Sequence analyses revealed 99-100% homology with already reported ESBL genes from around the world. However, mutations in CIT gene were found which indicates possible amino acid substitutions in more than one position
Terrorism is such a dangerous disease that has destroyed peace of many nations of the world. Terrorism, in all its forms, is condemnable. The author of this paper tried to encompass all the important factors and causes, which generate and consolidate terrorism in its different forms. This paper presents various causes of the phenomenon of terrorism, which include the material causes, the psychological causes, the behavioral causes, the political causes, the social causes, the economic causes and the ideological causes. The last segment of this dissertation discusses the remedies of the problem of terrorism. The necessary measures and suggestions have been suggested by the author to control the monster of terrorism. These includes to promote a moderate religious approach through education and preaching; to remove the misconception of the west against Islām; to refine our education and teaching methods by including relevant psychology and morality; our youth needs to use their energy in the social welfare activities to save them from becoming a victim of extremists and terrorists for having no purpose of life and for being idle; the Muslim rulers need to get close to their masses and remove alienation; a confident, unanimous condemnation from the responsible circles of the society should be promulgated; the youth must not rebel against their rulers and must not indulge in the matters of excommunication.
The radiation pattern and other electrical characteristics of an antenna primarily depend on its size and geometry. In the current age of communications, it is highly desirable to have compact and light weight communication devices. Therefore the most challenging issue of today’s wireless communication systems is to design antennas which are cost effective and of compact size without compromising the radiating efficiency and effectiveness. Since microstrip patch antennas are light weight, compact, easy to design and install; they are the best choice for today’s communication devices. That’s why patch antennas are widely used in numerous wireless applications as a single radiating element and as an array of multiple elements. However, designing of different shaped antennas to suit the electrical and/or physical requirements of the communication system is not an easy task. In this dissertation we have successfully designed microstrip patch antennas to achive desired electrical charcteristics such as frequency, bandwidth and quality factor alongwith the targeted physical characteristics such as length, radius or area etc. Keeping in mind the utilization of various shapes of antennas in communication systems; the dissertation includes designing of different geometrical shaped patch antennas such as square, circular and hexagonal. In addition to design patch antennas, we have succefully designed array of patch elements to be used in MIMO systems. The array has been designed for the desired electrical characteristics such as directivity, frequency, and return loss etc. Moreover, using this array design model, we estimated the channel capacity for ferquency selective Rayleigh fading channel. Since ultra wide band frequency systems are suitable for high data rates with low power consumption, we have particularly focused on this range of frequncy for antenna designing. Among all the heuristic approaches, literature shows that particle swarm optimization (PSO) and genetic algorithm (GA) are the most efficient and effective heuristic approaches in solving the problems of antenna and electromagnetics. Therefore we have employed these two approaches for designing and optimizing these antennas. We have also developed a new heuristic algorithm namely Wildebeest Herd Optimization (WHO) algorithm. It is based on the living wildebeest in their herd and migrating from one point to another for food and water. All the multi-geometrical antennas have been designed and optimized on WHO in addition to GA and PSO. The comparative analysis verifies that the proposed algorithm is more effective and efficient than the existing heuristic approaches. Moreover, artificial neural network (ANN) is employed to model the electrical/magnetic behavior of single antenna and arrays. The outcome of ANN models are compared with the results of numerical computational software Ansoft HFSS. In the light of this work, various future recommendations are also given at the end.