AHL AL-HADIS dan AHL RA\u27Y (Dinamika Hukum Islam dari Masa Peralihan Sahabat ke Masa Para Imam Madzhab)

Perbedaan pendapat dikalangan ulama di bidang-bidang hukum Islam sesungguhnya telah teradi pada masa Sahabat Nabi. Namun perbedaan-perbedaan tersebut masih daapat diatasi dengan kebijakan politik dan legalitas ijmak. Namun selesainya masa sahabat, yang dikenal dengan masa tabi\u27in (kira-kira dimulai pada tahun 41 H.) perbedaan pendapat tidak bisa diselesaikan seperti penyelesaian pada masa sahabat. Disinilah awal mula terjadinya proses peralihan hukum islam dari bentuk ijtihad yang bertumpuk pada keagungan sahabat kepada proses yang ilmiah dan terukur sampai lahirnya para imam-imam mazhab yang mengkodifikasikan hasil-hasil pemikiran hukumnya dalam bentuk kitab-kitab fiqh. Ahl al-Hadis dan Ahl al-ra\u27y adalah dua bentuk pemikiran hukum yang mengantar terjadinya prose peralihan itu. Masa itu adalah masa dimulainya USAha-USAha membentuk hukum islam agar sesuai dengan kondisi masyarakat dan rasionalitas

Structural insights into Clostridium perfringens delta toxin pore formation

Clostridium perfringens Delta toxin is one of the three hemolysin-like proteins produced by C. perfringens type C and possibly type B strains. One of the others, NetB, has been shown to be the major cause of Avian Nectrotic Enteritis, which following the reduction in use of antibiotics as growth promoters, has become an emerging disease of industrial poultry. Delta toxin itself is cytotoxic to the wide range of human and animal macrophages and platelets that present GM2 ganglioside on their membranes. It has sequence similarity with Staphylococcus aureus β-pore forming toxins and is expected to heptamerize and form pores in the lipid bilayer of host cell membranes. Nevertheless, its exact mode of action remains undetermined. Here we report the 2.4 Å crystal structure of monomeric Delta toxin. The superposition of this structure with the structure of the phospholipid-bound F component of S. aureus leucocidin (LukF) revealed that the glycerol molecules bound to Delta toxin and the phospholipids in LukF are accommodated in the same hydrophobic clefts, corresponding to where the toxin is expected to latch onto the membrane, though the binding sites show significant differences. From structure-based sequence alignment with the known structure of staphylococcal α-hemolysin, a model of the Delta toxin pore form has been built. Using electron microscopy, we have validated our model and characterized the Delta toxin pore on liposomes. These results highlight both similarities and differences in the mechanism of Delta toxin (and by extension NetB) cytotoxicity from that of the staphylococcal pore-forming toxins

Screening of Indonesia Medicinal Plants Producing Quorum Sensing Inhibitor

Antibiotic resistance of bacteria lead to create different way in the pathogen bacteria handling such us inhibit their quorum sensing mechanism. The goal of this study is to search quorum sensing inhibitor of seven Indonesia medicinal plants. The experiment was conducted by extracting the plants using ethyl acetate subsequently tested on reporter carrying luxR homologous and luxCDABE genes. Reporter luminescence used as indicator of quorum sensing inhibition. The results show that ethyl acetate extracts of buah adas (Foeniculum vulgare), bunga lawang (Illicium verum), selasih (Ocimum basilicum), temu ireng (Curcuma aeruginosa), temu giring (Curcuma heyneana), dan temu lawak (Curcuma xanthorriza) mampu menginhibisi quorum sensing pada Pseudomonas aeruginosa. Further analysis was done by observing several metabolites which directly influenced by quorum sensing. The experiment was design by growth Pseudomonas aeruginosa at LB medium occurring fennel seeds ethyl acetate extract in the various concentration. Number of biofilms, rhamnolipid and activity of LasA produced by Pseudomonas aeruginosa were then measured. The experiment shown LasA activity inhibition reaching 100% was obtained at growth media containing 1.52 mg / ml extract. There was a decrease at inhibition activity when the extract concentration was added above this value. Meanwhile, 19% inhibition of rhamnolipid production occurred at concentrations of ethyl acetate extract of 2.03 mg / ml in growth media. Different results obtained in the production of biofilm which is induced by fennel seeds ethyl acetate extract at the level 123%

Social interactions in the Burkholderia cepacia complex : biofilms and quorum sensing

Burkholderia cepacia complex bacteria are opportunistic pathogens that cause respiratory tract infections in susceptible patients, mainly people with cystic fibrosis. There is convincing evidence that B. cepacia complex bacteria can form biofilms, not only on abiotic surfaces (e.g., glass and plastics), but also on biotic surfaces such as epithelial cells, leading to the suggestion that biofilm formation plays a key role in persistent infection of cystic fibrosis lungs. This article presents an overview of the molecular mechanisms involved in B. cepacla complex biofilm formation, the increased resistance of sessile B. cepacia complex cells and the role of quorum sensing in B. cepacia complex biofilm formation

Pauli Blocking Effect on Efimov States Near Feshbach Resonance

In this Letter we study the effect of Pauli blocking on the Efimov states in a quantum Fermi gas and illustrate that the universal Efimov potential is altered at large distances. We obtain the universal spectrum flow of Efimov trimers when the Fermi density is varied and further consider the effect of scattering of trimers by the Fermi sea. We argue that the universal flow is robust against fluctuating particle-hole pairs that result in an infrared catastrophe in impurity problems

The Serrasalmidae (Pisces, Characoidei) from the Serra do Roncador, Mato Grosso, Brasil

Systematic account of the Fishes of the family Serrasalmidae (Characoidei, Cypriniformes) from the upper drainages of the Rios Araguaia and Xingu in Brazil, collected in 1968 by R.H. LOWE-McCONNELL, R. MILLS and J. GREEN. Eight species of the subfamily Myleinae are described, namely Myleus rubripinnis, M. schomburgki and a third unnamed species (that might be new to science), the rare Utiaritichthys sennaebragae and Acnodon normani (first collecting since the description of the types) and 3 Metynnis-species. Four species of the subfamily Serrasalminae are described: Serrasalmus striolatus ssp. (that has been compared with topotypical specimens of S. striolatus), S. humeralis (represented by topotypical individuals, which permitted an extended definition of the species), a geographic form of the common S. rhombeus and S. gibbus, an almost forgotten species that is tentatively restored