الإجارة وعقد التمليك

تخضع الإجارة لضوابط محددة تسمى الشروط، وهذه الشروط تنقسم إلى أربعة أقسام، شرط يكون مقتضى للعقد، وهو صحيح بالاتفاق، وشرط فيه مصلحة، سواء كانت مصلحة لأحد المتعاقدين أو للعقد، وشرط وصف في المبيع أو الثمن، وهو صحيح أيضاً، وشرط منفعة وهو من المختلف فيه، لذا فإن شروط العقود معظمها تكون جائزة. واعتمد الباحث على المنهج التحليلي، فتناول اللفظ الخاص بمحل الدراسة وعرفه لغة واصطلاحا، مستدلا عليه من مراجعه الأصلية، ثم عرَّج على أقوال الفقهاء لتعزيز ما ترجح منها، وذلك بعد أن بيَّنه بالتحليل والتوثيق. توصلت الدراسة إلى مجموعة من النتائج، أهمها: هنالك ضوابط لحالات العقود الجائزة، منها ما يتعلق بالأحكام ومنها ما يتعلق بالمعنى ومنها ما يتعلق بالشكل ومنها ما يتعلق بالزمان، كما سيتبين لنا في مواطن البحث. وأوصى الباحث بمجموعة من التوصيات أهمها ضرورة أن يلتزم المتعاقدون في معاملاتهم بالضوابط الشرعية لكل عقد وعدم الإعراض عن تلك الضوابط؛ لأن في ذلك مفسدة في أمورهم الدينية والدنيوية، واضطراب في أحوالهم ومعاشاتهم.

Pathological and Comparative Analysis of Newcastle Disease Virus of Sub-Genotypes Vi G and Vi M in Pigeons

Newcastle disease viruses (NDV) cause infection in avian species including both poultry and non-poultry worldwide. It is an extremely contagious disease also affecting vaccinated birds. Newcastle disease (ND) is endemic in Pakistan, viruses of sub-genotype VIIi in genotype VII, and sub-genotype VIg and Vim in genotypes VI of class II is continually effecting the pigeons and poultry production facilities. The identification and characterization of these viruses in poultry and non-poultry species is necessary in order to create realistic strategies for preventing and controlling NDV outbreaks. Genotype VI are also termed as pigeon paramyxoviryus-1, are frequently isolated and cause disease from the columbidae family. In this study, two PPMV-1 strains isolated from outbreaks in Lahore district were characterized by pathotypically, genotypically and detailed clinicopathologic assessment. The intracerebral pathogenicity index (ICPI) values for pigeon/Pak/Lahore/SA_1/2017 and pigeon/Pak/Lahore/SA_2/2017 were 1.51 and 1.52 respectively. The complete genome analysis based on full F gene coding sequences of two pigeon origin isolates from Lahore in 2017, along with previously published NDV strains available in GenBank was conducted. Analysis of F gene showed clustering of the isolates with genotype VI g and VI m. The genetic distance and phylogenetic analysis showed comparison with class II genotypes including vaccine strains. Both the strains were up to 10% genetically distant from LaSota (genotype II) isolate. Additionally, when compared for nucleotide and deduced amino acid sequence comparison several mutations were observed. The analysis of F and HN gene functional domains and receptor sites displayed conserved and mutated sequences. Results of genome analysis suggested that PPMV-1 isolates had antigenic variations from vaccine strain LaSota. For histopathological examination pigeon groups were challenged with pi/Lhr/SA_1/17 and pi/Lhr/SA_2/17 strains. Although severe clinical signs were not observed but microscopic results revealed lesions in multiple tissues from selected organs. Though limited data is available in Pakistan, this study will assist in introducing new control strategies and preventive measures for PPMV-1 outbreaks.