A Novel Electrochemically Active and Fe(III)-reducing Bacterium Phylogenetically Related to Clostridium butyricum Isolated from a Microbial Fuel Cell

An obligatory anaerobic bacterium was isolated from a mediator-less microbial fuel cell using starch processing wastewater as the fuel and designated as EG3. The isolate was Gram-positive, motile and rod (2.8–3.0 μm long, 0.5–0.6 μm wide). The partial 16S rRNA gene sequence and analysis of the cellular fatty acids profile suggested that EG3 clusters with Clostridium sub-phylum and exhibited the highest similarity (98%) with Clostridium butyricum. The temperature and pH optimum for growth were 37°C and 7.0, respectively. The major products of glucose and glucose/Fe(O)OH metabolism were lactate, formate, butyrate, acetate, CO₂and H₂. Growth was faster at the initial phase and the cell yield was higher when the medium was supplemented with Fe(O)OH than without Fe(O)OH. These results suggest that Fe(III) ion is utilised as an electron sink. Cyclic voltammetry showed that Clostridium butyricum EG3 cells were electrochemically active. It is a novel characteristic of strict anaerobic Gram-positive bacteria.     

A study of factors affecting the sensitivity of the passive haemagglutination method for serotyping Campylobacter jejuni and Campylobacter coli and recommendations for a more rapid procedure

Factors affecting the sensitivity of the passive haemagglutination method for serotyping campylobacters have been studied. The concentration of red blood cells during the haemagglutination stage of the procedure markedly affected the titer obtained. An increase in concentration of red blood cells resulted in a lower titer, with titers being inversely proportional to red blood cell concentration. No differences in titer were observed when erythrocytes were sensitized at a range of pH values between pH 5.0 and pH 8.0. The time required for antigen extraction and for red blood cell sensitization was shown to be 15 min each, thus resulting in a reduction in the time required for serotyping. Furthermore, use of avian erythrocytes enabled the haemagglutination reactions to be read after incubation for only 1 h. Combining these procedures with a rapid slide haemagglutination test enables a single worker to serotype over 100 C. jejuni and C. coli isolates within 1 working day.     

A comparison between biochemical tests and the 'CAMP' reaction for identification of Aeromonas spp.

Aeromonas bacteria (110 strains) from a variety of clinical, food and environmental sources, were identified using routine biochemical tests. Concurrently they were tested aerobically and anaerobically for their ability to perform synergistic haemolysis with Staphylococcus aureus (the 'CAMP' reaction). Results did not support a reported observation that the 'CAMP' reaction can he used to facilitate speciation of Aeromonas bacteria.     

The chondrocutaneous postauricular free flap

Use of the auriculomastoid region as a donor-site for a microvascular free flap is still not the general consensus. This report presents three patients with composite tissue defects of the face aesthetically reconstructed with a chondrocutaneous postauricular free flap. For its safe surgical application, additional anatomic knowledge was refined with cadaver study. Use of the chondrocutaneous postauricular free flap has some merits. Its dissection is straightforward and safer than when only the cutaneous unit is used. It also offers a more dependable vascularized composite tissue as a one-stage operation. With freedom of design, a variable combined facial defect can be delicately reconstructed. The final aesthetic results obtained were gratifying, and the donor-site deformity was minimal.     

New Class of Ni‐Rich Cathode Materials Li[NixCoyB1−x−y]O2 for Next Lithium Batteries

A new class of layered cathodes, Li[Ni_xCo_yB_1?x?y]O₂ (NCB), is synthesized. The proposed NCB cathodes have a unique microstructure in which elongated primary particles are tightly packed into spherical secondary particles. The cathodes also exhibit a strong crystallographic texture in which the a–b layer planes are aligned along the radial direction, facilitating Li migration. The microstructure, which effectively suppresses the formation of microcracks, improves the cycling stability of the NCB cathodes. The NCB cathode with 1.5 mol% B delivers a discharge capacity of 234 mAh g^?1 at 0.1 C and retains 91.2% of its initial capacity after 100 cycles (compared to values of 229 mAh g^?1 at 0.1 C and 78.8% for pristine Li[Ni_0.9Co_0.1]O₂). This study shows the importance of controlling the microstructure to obtain the required cycling stability, especially for Ni‐rich layered cathodes, where the main cause of capacity fading is related to mechanical strain in their charged state.     

Mechanism of silicate elution by hydrogen sulfide from bottom sediment in a brackish lake

Limnology - Highly concentrated dissolved silicate was detected in pore water from anoxic-reducing sediment in Lake Nakaumi, a brackish lake. Silicate concentration also simultaneously increased...