Repression of the alkaline phosphatase of Vibrio cholerae

The synthesis of alkaline phosphatase by two strains of Vibrio cholerae belonging to the Inaba and Ogawa serotypes has been examined in relation to the phosphate concentration of the culture medium. The synthesis of the enzyme in both strains was repressed in cells grown in the presence of a high concentration of inorganic phosphate. Lowering the phosphate content of the growth medium led to a derepression of enzyme activity. The presence of glucose in low phosphate medium stimulated the degree of derepression. The synthesis of the enzyme by strain Inaba 569B was more sensitive to inorganic phosphate than that of strain Ogawa 154. The enzyme was presumably located in the periplasmic space since it was released when the organisms were converted to spheroplasts

Immune effector responses to an excretory-secretory product of Giardia lamblia

The prior immunisation of mice with purified excretory-secretory product (ESP) led to a complete failure of Giardia lamblia colonisation following challenge inoculation of these animals with trophozoites. The prior immunisation of mice with ESP resulted in a significant stimulation of local immunity as evidenced by a significant enhancement of T helper/inducer activity along with a significant increase in immunoglobulin A-bearing cells. Further, the presence of anti-ESP antibodies in the serum of immunised as well as immunised-challenged animals indicated the stimulation of the systemic lymphoid system. This suggests that the ESP is highly immunogenic and it could be one of the major antigens of G. lamblia responsible for protection against the infection

Estimation of residual life of a cutting tool used in a machining process

A significant part of cost of machining is associated with non-optimum use of cutting tool. Moreover cutting tool failure is responsible for almost 20% of the machining downtime. Thus, having knowledge of residual life of cutting tool is highly recommended so as to maximise the availability time and reduce the machining cost. The aim of this work is to find out residual life of a worn cutting tool which has been used for turning of Ti-6Al-4V alloy under constant cutting condition. The lognormal distribution is used to model the cutting tool life data. Remaining useful life of cutting tool is estimated using Mean Remaining Life (MRL) function. The results obtained from model are compared with the experimental results and it shows good agreement

Enterotoxin production, DNA repair and alkaline phosphatase of Vibrio cholerae before and after animal passage

Summary: Three strains of Vibrio cholerae differing in biotype, serotype and/or toxinogenicity were studied. The capability for dark repair of DNA and stability of alkaline phosphatase decreased concomitantly with toxinogenicity on laboratory passage of highly enterotoxinogenic strain 569B. These properties could be restored by passaging strain 569B once through a guinea-pig

N-(6-Bromo­meth­yl-2-pyrid­yl)acetamide

The title acetamide compound, C8H9BrN2O, crystallizes with three crystallographically independent mol­ecules (A, B and C) in the asymmetric unit. In mol­ecule A, the mean plane through the acetamide unit is inclined at a dihedral angle of 4.40 (11)° with respect to the pyridine ring [10.31 (12) and 2.27 (11)°, respectively, for mol­ecules B and C]. In the crystal structure, mol­ecules are inter­connected into sheets parallel to the ac plane by N—H⋯O, C—H⋯Br, C—H⋯O and C—H⋯N hydrogen bonds. The structure is further stabilized by weak inter­molecular C—H⋯π inter­actions

Acute otitis externa: Consensus definition, diagnostic criteria and core outcome set development.

OBJECTIVE: Evidence for the management of acute otitis externa (AOE) is limited, with unclear diagnostic criteria and variably reported outcome measures that may not reflect key stakeholder priorities. We aimed to develop 1) a definition, 2) diagnostic criteria and 3) a core outcome set (COS) for AOE. STUDY DESIGN: COS development according to Core Outcome Measures in Effectiveness Trials (COMET) methodology and parallel consensus selection of diagnostic criteria/definition. SETTING: Stakeholders from the United Kingdom. SUBJECTS AND METHODS: Comprehensive literature review identified candidate items for the COS, definition and diagnostic criteria. Nine individuals with past AOE generated further patient-centred candidate items. Candidate items were rated for importance by patient and professional (ENT doctors, general practitioners, microbiologists, nurses, audiologists) stakeholders in a three-round online Delphi exercise. Consensus items were grouped to form the COS, diagnostic criteria, and definition. RESULTS: Candidate COS items from patients (n = 28) and literature (n = 25) were deduplicated and amalgamated to a final candidate list (n = 46). Patients emphasised quality-of-life and the impact on daily activities/work. Via the Delphi process, stakeholders agreed on 31 candidate items. The final COS covered six outcomes: pain; disease severity; impact on quality-of-life and daily activities; patient satisfaction; treatment-related outcome; and microbiology. 14 candidate diagnostic criteria were identified, 8 reaching inclusion consensus. The final definition for AOE was 'diffuse inflammation of the ear canal skin of less than 6 weeks duration'. CONCLUSION: The development and adoption of a consensus definition, diagnostic criteria and a COS will help to standardise future research in AOE, facilitating meta-analysis. Consulting former patients throughout development highlighted deficiencies in the outcomes adopted previously, in particular concerning the impact of AOE on daily life

Vibration characteristics of pretwisted uniform cross-section cantilever beams allowing for shear deformation and rotary inertia.

This thesis is concerned with the vibrational characteristics of pre-twisted cantilever beams of uniform cross-section allowing for shear deformation and rotary inertia. A method of solution of the differential equations of motion allowing for shear deformation and rotary inertia is presented which is an extension of the method developed by Dawson for the solution of the differential equations of motion of pre-twisted beams neglecting shear and rotary inertia effects. This method consists in transforming the original equations into a set of first order differential equations and solving by Runga-Kutta step-by-step integration method. The method has been programmed for an Elliot-503 computer in Algol language and the natural frequencies and mode shapes of vibration are obtained for various breadth to depth ratio beams of lengths ranging from 3 inches to 20 inches ana pre-twisted angle up to 90 degrees, for up to fifth mode of vibration. The results are compared with other investigators work where available and good agreement is obtained. The natural frequencies and mode shapes of vibration are obtained by experiment and are compared to theoretical results. The effect of the variation of the shear stress factor upon the natural frequencies and mode shapes of vibration of pre-twisted cantilever beams is also examined