Abstract: A tennis ball comprising a hollow core and a cover, the core being formed from a composition including rubber, in which the composition comprises recycled tennis ball material.

Abstract: We describe a method of determining a food-to-biomass ratio in an aqueous fluid the method comprising: providing an aqueous fluid comprising viable biomass and food for said biomass, and wherein there is insufficient available food to sustain all said viable biomass; using a sensor (for example a respirometer or a sensor for sensing an amount of ammonia, ammonium, nitrates or nitrites) to determine an amount of food in said aqueous fluid available to said biomass; determining a measure of viable biomass in said aqueous fluid by measuring polarisability of viable biomass cells in an AC electric field; and determining a food-to-biomass ratio from said amount of food and said measure of viable biomass.

Abstract: We describe a method of selectively testing a liquid sample for the presence of a specific living biological entity, the method comprising: preparing a plurality of culture vessels each for selective detection of the presence of a different living biological entity, wherein preparing a said culture vessel comprises: providing a culture vessel comprising a sealable chamber for receiving and culturing a liquid sample such that presence of said biological entity is detectable by detecting a change in pressure in a head space of said chamber; providing a selective growth medium in said culture vessel, wherein said selective growth medium is in a dry form and selectively facilitates growth of a specific living biological entity, and providing the culture vessel with an identifier to identity said specific biological entity; providing a test system comprising a device to receive said culture vessel and to detect said change in pressure in said head space of said chamber, the device further comprising a temperature

Abstract: We describe a floating respirometer, in particular for monitoring an activated sludge vessel of a sewage treatment plant. The device comprises: a buoyancy device to allow the respirometer to float in an aqueous liquid; a respirometer chamber, supported by the buoyancy device and arranged such that, when the respirometer is floating in said aqueous liquid, said chamber is partially filled with said aqueous liquid and defines an enclosed head space above said aqueous liquid; and a gas sensor in gaseous communication with said head space.

Abstract: We describe a method of closed-loop control of a waste water treatment plant, the method comprising: obtaining a fluid sample from a fluid of said plant; providing said fluid sample to a sealed chamber such that said fluid sample incompletely fills said sealed chamber leaving a headspace; incubating said fluid sample in said sealed chamber; determining a change in pressure in said headspace during said incubating; and controlling a degree of aeration of said waste water treatment plant responsive to said change in pressure. We also describe a method of measuring one or both of the food content and the biomass content of a fluid of a waste water treatment plant, the method comprising determining a value for one or both of food content and biomass content from a change in pres sure.

Abstract: We describe a system for monitoring effluent discharge to determine one or both of a biochemical oxygen demand (BOD) and a toxicity of the discharge. The system comprises: a culture vessel comprising a sealable chamber for culturing a fluid sample and a pressure measurement transducer for measuring a pressure in a headspace of the chamber; and a data processing system to: input pressure data from the pressure measurement transducer; and determine a value for one or both of BOD and toxicity from the change in pressure measured by the pressure transducer.

Abstract: The present invention relates to the use of magnets in the treatment of human disorders that are caused by or contributed to by Autonomic Nervous System imbalance and include menopause symptoms wherein the magnetic product comprises a magnet having positive and negative poles, the magnet having an additional metallic directional plate which distorts the magnetic field distribution around the magnet so as to attenuate the magnetic field in the vicinity of the positive pole of the magnet.

Abstract: The present invention relates to the use of magnets in the treatment of cancer wherein the magnetic product comprises a magnet having positive and negative poles, the magnet having an additional metallic directional which distorts the magnetic field distribution around the magnet so as to attenuate the magnetic field in the vicinity of the positive pole of the magnet. The invention also relates to methods of treatment using those magnets.