Mechanical refrigeration and ventilation in cold-storage facilities.

"August 1982."

Repairs and utilities : refrigeration, air conditioning, mechanical ventilation, and evaporative cooling.

Mode of access: Internet.

Drying ear corn by mechanical ventilation /

Supersedes its Leaflet 333 and 334.

Ventilation for dwellings, rural schools and stables,

Mode of access: Internet.

Modern school buildings, elementary and secondary : a treatise on the planning, arrangement, and fitting of day and boarding schools, having special regard to school discipline, organisation, and educational requirements, with chapters on the treatment of class rooms, lighting, warming, ventilation, and sanitation.

Includes index.

Spontaneous hypertension, its pathogenesis and complications : proceedings of the 2d International Symposium on the Spontaneously Hypertensive Rat /

Mode of access: Internet.

A catalogue of the plants growing in Bombay and its vicinity; spontaneous, cultivated or introduced, as far as they have been ascertained.

No more published.

Entanglement induced by spontaneous emission in spatially extended two-atom systems

The role of the collective antisymmetric state in entanglement creation by spontaneous emission in a system of two non-overlapping two-level atoms has been investigated. Populations of the collective atomic states and the Wootters entanglement measure (concurrence) for two sets of initial atomic conditions are calculated and illustrated graphically. Calculations include the dipole-dipole interaction and a spatial separation between the atoms that the antisymmetric state of the system is included throughout even for small interatomic separations. It is shown that spontaneous emission can lead to a transient entanglement between the atoms even if the atoms were prepared initially in an unentangled state. It is found that the ability of spontaneous emission to create transient entanglement relies on the absence of population in the collective symmetric state of the system. For the initial state of only one atom excited, entanglement builds up rapidly in time and reaches a maximum for parameter values corresponding roughly to zero population in the symmetric state. On the other hand, for the initial condition of both atoms excited, the atoms remain unentangled until the symmetric state is depopulated. A simple physical interpretation of these results is given in terms of the diagonal states of the density matrix of the system. We also study entanglement creation in a system of two non-identical atoms of different transition frequencies. It is found that the entanglement between the atoms can be enhanced compared to that for identical atoms, and can decay with two different time scales resulting from the coherent transfer of the population from the symmetric to the antisymmetric state. In addition, it was found that a decaying initial entanglement between the atoms can display a revival behaviour.

A deletion mutation in GDF9 in sisters with spontaneous DZ twins

A loss of function mutation in growth differentiation factor 9 (GDF9) in sheep causes increased ovulation rate and infertility in a dosage-sensitive manner. Spontaneous dizygotic (DZ) twinning in the human is under genetic control and women with a history of DZ twinning have an increased incidence of multiple follicle growth and multiple ovulation. We sequenced the GDF9 coding region in DNA samples from 20 women with DZ twins and identified a four-base pair deletion in GDF9 in two sisters with twins from one family. We screened a further 429 families and did not find the loss of function mutation in any other families. We genotyped eight single nucleotide polymorphisms across the GDF9 locus in 379 families with two sisters who have both given birth to spontaneous DZ twins (1527 individuals) and 226 triad families with mothers of twins and their parents (723 individuals). Using case control analysis and the transmission disequilibrium test we found no evidence for association between common variants in GDF9 and twinning in the families. We conclude that rare mutations in GDF9 may influence twinning, but twinning frequency is not associated with common variation in GDF9.

Standing with the assistance of a tilt table improves minute ventilation in chronic critically ill patients

Objective: To investigate the effect of standing with assistance of the tilt table on ventilatory parameters and arterial blood gases in intensive care patients. Design: Consecutive sample. Setting: Tertiary referral hospital. Participants: Fifteen adult patients who had been intubated and mechanically ventilated for more than 5 days (3 subjects successfully weaned, 12 subjects being weaned). Intervention: Passive tilting to 70degrees from the horizontal for 5 minutes using a tilt table. Main Outcome Measures: Minute ventilation (VE), tidal volume (VT), respiratory rate, and arterial partial pressure of oxygen (Pao(2)) and carbon dioxide (Paco(2)). Results: Standing in the tilted position for 5 minutes produced significant increases in VE (P

Entangling two atoms via spontaneous emission

We discuss the creation of entanglement between two two-level atoms in the dissipative process of spontaneous emission. It is shown that spontaneous emission can lead to a transient entanglement between the atoms even if the atoms were prepared initially in an unentangled state. The amount of entanglement created in the system is quantified by using two different measures: concurrence and negativity. We find analytical formulae for the evolution of concurrence and negativity in the system. We also find the analytical relation between the two measures of entanglement. The system consists of two two-level atoms which are separated by an arbitrary distance r(12) and interact with each other via the dipole-dipole interaction, and the antisymmetric state of the system is included throughout, even for small interatomic separations, in contrast to the small-sample model. It is shown that for sufficiently large values of the dipole-dipole interaction initially the entanglement exhibits oscillatory behaviour with considerable entanglement in the peaks. For longer times the amount of entanglement is directly related to the population of the slowly decaying antisymmetric state.

Ventilation rate and behavioural responses of two species of intertidal goby (Pisces : Gobiidae) at extremes of environmental temperature

We investigated the behavioural responses of two gobiid fish species to temperature to determine if differences in behaviour and ventilation rate might explain any apparent vertical zonation. A survey of the shore at Manly, Moreton Bay revealed Favonigobius exquisitus to dominate the lower shore and Pseudogobius sp. 4 the upper shore. These species were exposed to a range of temperatures (15-40 degreesC) in aquaria for up to 6 h. At 20 degreesC F. exquisitus exhibited a mean gill ventilation rate of 26 +/- 1.4 bpm (beats per minute) differing significantly from Pseudogobius, which ventilated at a fivefold greater rate of 143 +/- 6 bpm. The ventilation rate in F. exquisitus underwent a fivefold increase from normal local water temperature (20 degreesC) to high temperature (35 degreesC) conditions, whereas that of Pseudogobius did not even double, suggesting that Pseudogobius sp. is a better thermal regulator than F. exquisitus. While both species emerged from the water at high temperatures (>30 degreesC) the behaviours they exhibited while immersed at high temperature were quite different. F. exquisitus undertook vertical displacement movements we interpret as an avoidance response, whereas Pseudogobius sp. appeared to use a coping strategy involving movements that might renew the water mass adjacent to its body. The thermal tolerances and behaviours of F. exquisitus and Pseudogobius sp. are in broad agreement with their vertical distribution on the shore.

Phase-space analysis of bosonic spontaneous emission

We present phase-space techniques for the modelling of spontaneous emission in two-level bosonic atoms. The positive-P representation is shown to give a full and complete description within the limits of our model. The Wigner representation, even when truncated at second order, is shown to need a doubling of the phase-space to allow for a positive-definite diffusion matrix in the appropriate Fokker-Planck equation and still fails to agree with the full quantum results of the positive-P representation. We show that quantum statistics and correlations between the ground and excited states affect the dynamics of the emission process, so that it is in general non-exponential. (c) 2005 Elsevier B.V. All rights reserved.

Pressure support ventilation with the ProSeal (R) laryngeal mask airway. A comparison of sevoflurane, isoflurane and propofol

Background and objective: There are no data about the influence of anaesthetics on cardiovascular variables during pressure support ventilation of the lungs through the laryngeal mask airway. We compared propofol, sevoflurane and isoflurane for maintenance of anaesthesia with the ProSeal (R) laryngeal mask airway during pressure support ventilation. Methods: Sixty healthy adults undergoing peripheral musculo-skeletal surgery were randomized for maintenance with sevoflurane end-tidal 29%, isoflurane end-tidal 1.1% or propofol 6 mg kg(-1) h(-1) in oxygen 33% and air. Pressure support ventilation comprised positive end-expiratory pressure set at 5 cmH(2)O, and pressure support set 5 cmH(2)O above positive end-expiratory pressure. Pressure support was initiated when inspiration produced a 2 cmH(2)O reduction in airway pressure. A blinded observer recorded cardiorespiratory variables (heart rate, mean blood pressure, oxygen saturation, air-way occlusion pressure, respiratory rate, expired tidal volume, expired minute volume and end-tidal CO2), adverse events and emergence times. Results: Respiratory rate and minute volume were 10-21% lower, and end-tidal CO2 6-11% higher with the propofol group compared with the sevoflurane or isoflurane groups, but otherwise cardiorespiratory variables were similar among groups. No adverse events occurred in any group. Emergence times were longer with the propofol group compared with the sevoflurane or isoflurane groups (10 vs. 7 vs. 7 min). Conclusion: Lung ventilation is less effective and emergence times are longer with propofol than sevoflurane or isoflurane for maintenance of anaesthesia during pressure support ventilation with the ProSeal (R) laryngeal mask airway. However, these differences are small and of doubtful clinical importance.