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Summary Thermal death data were obtained for B. stearothermophilus spores heated in (a) a laboratory scale, direct heating UHT plant and (b) a larger scale direct heating UHT plant. These were compared with the corrected data from experiments in which spores of the same batch were heated in capillary tubes. Temperature coefficients (Q10 values) for inactivation of spores in UHT plants were higher than those for spores in capillary tubes but agreement was closer when spores were suspended in water than in milk. For aqueous spore suspensions, the discrepancy between plants and capillaries was least for the laboratory scale plant. the divergence always became greater at lower temperatures and the D values were coincident at 145°C. Possible reasons for these various effects are discussed.

Summary A study was initiated into the inconsistencies reported to occur between (a) estimations of sterilizing efficiency (of UHT plants) based on experiments in which bacterial spores are heated in capillary tubes at sub-UHT temperatures and (b) determinations of sterilizing efficiency made by heating spores at UHT temperatures in the plants themselves. Capillary tube experiments were extended to 160°C with the aim of obtaining data suitable for direct comparison, i.e. obviating any need for extrapolation, with those obtained by plant inoculation. As heat-treatment temperatures were increased from 120 to 160°C the shape of the survivor curves became increasingly sigmoidal, possibly due to the greater significance of heat transfer times at high temperatures. Temperature coefficients for spores suspended in water were constant (Q10= 23.5) up to 132.5°C and for spores suspended in milk were constant (Q10= 13.2) up to 142.5°C; beyond these temperatures, Q10 values gradually diminished. Such an effect could not be explained by Arrhenius kinetics and again may reflect the physical limitations of the capillary tube system. Its importance is discussed in relation to the value of capillary tube experiments for predicting the sterilizing efficiency of UHT plants.

Hydrographic measurements from the 1994 Arctic Ocean Section show how the Makarov and Canada basins of the Arctic Ocean are related, and demonstrate their oceanographic connections to the Eurasian Basin. The inflow into the Makarov Basin consists largely of well-ventilated water within a broad band of densities from a boundary flow over the Siberian end of the Lomonosov Ridge. The boundary flow contains a significant component of dense shelf water likely originating in the Barents, Kara, and Laptev Seas. Earlier ice camp data show that the Canada Basin is relatively more isolated from this ventilation source. In the Canada Basin shelf sources influenced by Bering Sea water appear to add cold waters with high silicate concentrations to the halocline and deeper. In 1994 the halocline silicate maximum over the central Makarov Basin was absent, evidence of the recent displacement of the upper (S∼ 33.1) halocline water from the Chukchi-East Siberian Sea region by water from the Eurasian Basin. Much of the Makarov Basin water in and below the halocline is in fact from the Eurasian Basin, with admixture of waters from the Canada Basin suggested by their higher silicate concentrations. Mid-depth eddies may transport anomalous properties into the central Arctic and create property gradients or fronts in mid-depth and deep waters. The complex topography of the Mendeleyev Ridge-Chukchi Plateau region also may assist spreading of water from the boundary into the interior. Atlantic layer characteristics in 1994 differed from previous general depictions. In particular the core temperatures at the Chukchi-Mendeleyev boundary were at least 0.2°C warmer on average than indicated in earlier work. The recent warming at intermediate depth has resulted from inflow of Atlantic waters that have been cooled relatively little during their transit of the Norwegian Sea.

Major changes in temperature and tracer properties within the Arctic Ocean are evident in a comparison of data obtained during the 1994 Arctic Ocean Section to earlier measurements. (1) Anomalously warm and well-ventilated waters are now found in the Nansen, Amundsen and Makarov basins, with the largest temperature differences, as much as 1 °C, in the core of the Atlantic layer (200–400 m). Thus thermohaline transition appears to follow from two distinct mechanisms: narrow (order 100 km), topographically-steered cyclonic flows that rapidly carry new water around the perimeters of the basins; and multiple intrusions, 40–60 m thick, which extend laterally into the basin interiors. (2) Altered nutrient distributions that within the halocline distinguish water masses of Pacific and Atlantic origins likewise point to a basin-wide redistribution of properties. (3) Distributions of CFCs associated with inflows from adjacent shelf regions and from the Atlantic demonstrate recent ventilation to depths exceeding 1800 m. (4) Concentrations of the pesticide HCH in the surface and halocline layers are supersaturated with respect to present atmospheric concentrations and show that the ice-capped Arctic Ocean is now a source to the global atmosphere of this contaminant. (5) The radionuclide 129I is now widespread throughout the Arctic Ocean. Although the current level of 129I level poses no significant radiological threat, its rapid arrival and wide distribution illustrate the speed and extent to which waterborne contaminants are dispersed within the Arctic Ocean on pathways along which other contaminants can travel from western European or Russian sources.

Potential temperature (θ) and salinity (S) data obtained along the perimeter of the southern Canadian Basin north of the East Siberian Sea in 1993 aboard the CCGS Henry Larsen show higher temperatures in waters of Atlantic origin than in available climatological data for the Canadian Basin. In particular, a front is observed near the Mendeleyev Ridge which separates the cooler Atlantic waters of the Canada Basin from the warmer Atlantic waters observed in the Makarov Basin. The front is further characterized by a change in the θ/S slope of Arctic thermocline water, and by thermohaline intrusions (θ and S reversals) within the Atlantic layer. The idea that this warm variety of Atlantic water has come recently from the Eurasian Basin is supported by its higher level of the tracer CFC-11.

In less than half a century, allergy, originally perceived as a rare disease, has become a major public health threat, today affecting the lives of more than 60 million people in Europe, and probably close to one billion worldwide, thereby heavily impacting the budgets of public health systems. More disturbingly, its prevalence and impact are on the rise, a development that has been associated with environmental and lifestyle changes accompanying the continuous process of urbanization and globalization. Therefore, there is an urgent need to prioritize and concert research efforts in the field of allergy, in order to achieve sustainable results on prevention, diagnosis and treatment of this most prevalent chronic disease of the 21st century. The European Academy of Allergy and Clinical Immunology (EAACI) is the leading professional organization in the field of allergy, promoting excellence in clinical care, education, training and basic and translational research, all with the ultimate goal of improving the health of allergic patients. The European Federation of Allergy and Airways Diseases Patients' Associations (EFA) is a non-profit network of allergy, asthma and Chronic Obstructive Pulmonary Disorder (COPD) patients' organizations. In support of their missions, the present EAACI Position Paper, in collaboration with EFA, highlights the most important research needs in the field of allergy to serve as key recommendations for future research funding at the national and European levels. Although allergies may involve almost every organ of the body and an array of diverse external factors act as triggers, there are several common themes that need to be prioritized in research efforts. As in many other chronic diseases, effective prevention, curative treatment and accurate, rapid diagnosis represent major unmet needs. Detailed phenotyping/endotyping stands out as widely required in order to arrange or re-categorize clinical syndromes into more coherent, uniform and treatment-responsive groups. Research efforts to unveil the basic pathophysiologic pathways and mechanisms, thus leading to the comprehension and resolution of the pathophysiologic complexity of allergies will allow for the design of novel patient-oriented diagnostic and treatment protocols. Several allergic diseases require well-controlled epidemiological description and surveillance, using disease registries, pharmacoeconomic evaluation, as well as large biobanks. Additionally, there is a need for extensive studies to bring promising new biotechnological innovations, such as biological agents, vaccines of modified allergen molecules and engineered components for allergy diagnosis, closer to clinical practice. Finally, particular attention should be paid to the difficult-to-manage, precarious and costly severe disease forms and/or exacerbations. Nonetheless, currently arising treatments, mainly in the fields of immunotherapy and biologicals, hold great promise for targeted and causal management of allergic conditions. Active involvement of all stakeholders, including Patient Organizations and policy makers are necessary to achieve the aims emphasized herein. © 2012 Papadopoulos et al.

This paper is a condensed version of a report on the preliminary results of a research cruise under the direction of the U. S. Geological Survey, on board the United States Coast Guard Cutter Polar Star to Northwind Ridge and Canada Basin of the Western Arctic Ocean, during the period August 16‐September 15, 1993. Major objectives of the cruise were to: survey the geology of the North‐wind Ridge and Canada Basin; determine whether radionuclide contamination from disposal of solid and liquid nuclear wastes by the former Soviet Union in the Kara and Barents seas had penetrated the North American Arctic; acquire sediment cores in support of research on the history of glaciation in the region; and gain a better understanding of water structure and currents, sea‐ice physics, and sediment and nutrient transport.

The response characteristics of a family of conductivity cells typical of those employed in profiling instruments has been examined from a theoretical standpoint, and the conditions established under which such a cell exhibits a linear transfer function. The necessary conditions are that conductivity changes are small, and that the molecular diffusion of conductivity within the cell is negligible over times of interest. The first of these conditions is almost always satisfied, as is the second for the diffusion of salt; for conductivity changes arising from temperature, however, molecular diffusion of temperature imposes a severe limit on the linearity of the response. The analysis fully accounts for the fluid flow within the cell, and includes the effect of the internal frictional losses on the cell entry flow speed—an important effect on cell response. Numerical results of the step responses of the Neil Brown and Guildline cells are presented and those for the former closely match available exp...

The freezing point of seawater has been measured in the salinity range 18‰ < S ≤ 35‰ at atmospheric pressure showing results consistently lower than Hansen's (1904) values. Our data fit the curve Tƒ = −0.036 - 0.0499S -; 0.000112S2 with a standard deviation of ±0.0025°C. This equation also stays within −0.01°C of Hansen's data in the range 9–35‰. Determinations of the change of freezing point with pressure were made for three salinities in the range 27‰ < S ≤ 35‰ showing a constant slope of 7.59×10−3 °C/bar up to 100 bars independent of salinity.

Measurements made in Cambridge Bay, N.W.T., during the winter show that the breaking of internal waves on the shore influences downward salt transport from the homogeneous surface layer produced by saline convection beneath sea ice during growth. Denser water from the shallows, where the depth of this convective layer is limited by the sea bed, flows down the slope to the layer interface contour where the breaking waves introduce turbulence aiding mixing of the convecting water into the lower layer. Away from the boundaries entrainment of salt from the lower to the upper mixed layer is aided by the internal waves on the interface. These two salt transports, downward at the boundaries upward over the basin, produce horizontal salinity gradients which overall make water in the shallows less saline than the surface layer of the basin. The energies available for these mixing processes are estimated.

The flavour and nutritional quality of UHT processed milk is discussed and suggestions are made for ways of minimizing undesirable changes during heat treatment. UHT treatment of milk using an infusion heater is described, and it is concluded that whole milk processed in this way is a typical directly heated UHT milk.

SummaryIndirectly heated ultra-high-temperature (UHT) processed milk was prepared with initially high, medium, and low dissolved O2 contents of 8·9, 3·6 and 1·0 ppm respectively, aseptically bottled, and tested at intervals during storage at room temperature for 150 d. Flavour acceptability increased to a maximum after a few days, but declined slowly after about 6 d; the increase was associated with less off-flavour described as ‘cabbagey’, and the decrease with more ‘stale’ off-flavour descriptions. Milks with higher initial O2 contents were preferred up to 8–13 d, but thereafter acceptability was independent of initial O2 content. Sulphydryl group (–SH) contents rapidly decreased and O2 levels correspondingly declined in the first few days as the flavour improved. Loss of –SH was lower with lower initial O2 contents, and moderate –SH content remained in low O2 samples for several weeks. Ferricyanide reducing (FR) values did not satisfactorily measure stale flavour development. They were initially high and decreased during the first 13 d at rates dependent on O2 content. After 20 d the FR values began to rise in high O2 samples, but continued to decline slowly in low O2 samples up to 90d although stale flavour was increasing.High initial O2 contents resulted in rapid depletion of ascorbic acid and folic acid during storage. Losses of vitamin B12 were small, but were higher with high O2 contents than with low.The beneficial effect of O2 on flavour, therefore, appears to be so slight and confined to such a short period in the early life of the milk as to be completely outweighed by the adverse nutritional effects.

Twenty-eight profiles of temperature and salinity down to 1 km depth have been measured in the area north from the coast of Svalbard to latitude 84°40′N between 0 and 32°E longitude. They show Atlantic waters of the West Spitsbergen Current entering the Arctic Ocean in a bifilimentary mode, one filament following the coastline and the other, 300 km farther north, apparently following the continental-shelf break. The profiles show these filaments mixing into the ambient water in a series of intrusive layers which are remarkably uniform over distances of hundreds of kilometers. A “triple peak” structure at the Atlantic water maximum is the dominant oceanographic characteristic of the area with salt fingering occurring on the upper surface of the cold intrusions and indications of double diffusive exchanges through the lower. surface. A system or eddies or meanders is postulated as the mechanism for the production of multiple fronts allowing the intrusive layers to extend to distances much greater t...

Studies of water movement in the Aafardlikavsâ/Qaumarujuk fjord system in West Greenland have barn carried out in order to understand the movement of mine tailings discharged into Agfardlikavsâ Fjord. Observations are explained in terms of resonance of the internal tide, deep convection associated with sea ice growth, and basin water exchange occurring at the time of ice breakup in early summer. Mixing processes are dominated by these events, illustrating the limitations of any seasonal description based on conventional diffusive processes.

SummaryAn experimental ultra-high-temperature milk sterilizer, of 1140 1/h capacity and capable of operation as a plate-type indirect heating plant or as a steaminto-milk direct heating plant, has been installed for comparisons of the milk produced by the direct and indirect processes. The sterilizer and its ancillary equipment are described, together with methods of plant sterilization and milk processing. Time-temperature profiles of the plant are given for both modes of operation.

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SummaryThe distribution of protein nitrogen was determined in milk treated by an experimental ultra-high-temperature (UHT) plant, operating alternatively as an indirect or as a direct heating plant.The extent of denaturation of β-lactoglobulin can be used to assess the relative severity of UHT heat treatments; this criterion was used to compare the indirect and direct arrangements of the plant with each other and with other published results.The time-temperature profiles of the plant were used to calculate the expected extent of denaturation of β-lactoglobulin during treatment of the milk. The results of the calculations are in fair agreement with the analytical results.

SummaryThe variation of sporicidal efficiency with processing temperature was determined for an experimental ultra-high-temperature (UHT) milk sterilizer operating alternatively as an indirect or as a direct heater. Whole milk was inoculated with large numbers of spores of Bacillus subtilis 786 and Bacillus stearothermophilus TH24, and the proportion of spores surviving the sterilizing process was calculated from dilution and colony counts on the untreated and treated milk. The results for B. subtilis spores were unreliable, and the dilution count results for B. stearothermophilus spores were influenced by the inhibitory effect of the UHT processed milk. The results for the colony counts of B. stearothermophilus spores were preferred as a basis for the comparison of the direct and indirect processes. Over the range of processing temperatures 137–145 °C it was found that the sterilizing temperature had to be 3–4 degC higher with direct heating than with indirect heating to give equal spore destructions.

SummaryWhen heat treatments of the same sporicidal effectiveness were given, directly heated ultra-high-temperature sterilized milk gave twice as much sediment as indirectly heated milk after storage at room temperature for 100 days. Both types of process reduced the rate of clotting of the milk with pepsin and rennin, but the effect of the indirect process was markedly greater than that of the direct process.

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SummaryA comparison was made of the effects of direct and of indirect ultra-high-temperature (UHT) processing of milk, under standardized operating conditions giving equal sporicidal effects, on some of the more labile water-soluble vitamins and on vitamin A and carotene. The effects of processing per se were negligibly small, and the method of processing was important only in so far as the presence of residual oxygen in the sterilized milk has been found to cause losses of folic acid and ascorbic acid during storage subsequent to sterilization. The incorporation of a de-aerator vessel, to reduce the oxygen level in the indirectly heated milk and so eliminate the adverse effects of oxygen during storage, had no effect on the vitamin loss occurring during heat treatment. It is concluded that milk produced by indirect heating plant incorporating a de-aerator should be similar in vitamin content to milk produced on a direct heating plant, both immediately after processing and after storage.

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A method for determining low concentrations of hydrogen peroxide (H2O2) in water, based on the chemiluminescent oxidation of 3-aminophthalhydrazide (luminol) by H2O2 in the presence of a copper ion catalyst, is described. Levels of H2O2 down to 3 × 10-8 mol/1 (1 ppb) can be determined. The method may be used to monitor the amount of residual H2O2 in aseptically filled packages sterilized with H2O2 before filling.

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Although fertility control may occur without an organized family planning program, as it has in the West, programs reduce fertility among the poor and disadvantaged. A family planning program may emphasize the health of mother and child or directly reducing fertility, but the goal is to supply safe and effective methods of birth control. An efficient program optimizes the mix of fertility control methods for a given objective. Ideally, the mix will be dynamic, changing over time. In 1976 a study of 37 developing countries indicated that only 4 were offering all 5 principal methods. Recommendations for modifying family planning programs so they are most efficient are to use existing technology and methods; providing variety of methods and delivery systems; emphasizing couple continuation rather than method continuation. Contraceptive prevalence could be expanded to 40% or more of eligible couples if existing methods were made available through a variety of delivery systems. As more countries have moved to abolish prescriptions for oral contraceptives community-based distribution has become more effective and useful. A vigorous commercial distribution system could add 9 or 10 points to prevalence rates. A country with a high proportion of deliveries in government health facilities could surpass the 3% prevalence rate shown for the IUD in the health system, espccially if a postpartum IUD program were implemented.

SummaryAdditions of potassium iodate to milk at 0·05 and 0·1 mM (10 and 20 ppm) before UHT treatment markedly reduced the rate at which pressure built up during processing. This permitted the use of longer processing times before unacceptable pressures were reached in the heat exchangers. Iodate reduced the amount of protein deposited, particularly in the higher temperature sections of the plant, but had no effect on the deposition of minerals. The more compact nature of the highly mineral deposits offered less resistance to the flow path. Reduction in the amount of protein deposited is likely to be caused by increased denaturation of β-lactoglobulin and oxidation of heat activated sulphydryl groups by the iodate, thus reducing the formation of high molecular weight polymers of sulphur-containing proteins at the heated surfaces. Increasing the level of sulphydryl groups in the milk through the addition of L-cysteine-HCl caused an increase in the amount of deposit formed during UHT treatment. Whilst little detrimental effect on the quality of the milk resulted from additions of iodate at 0·05 mM, milks with 01 mM-iodate became bitter during subsequent aseptic storage. Bitterness was a result of iodate-induced proteolysis of casein.

Until recently, contraceptive product development, the translation of a research finding into a final product, was successfully carried out by profit-making, commercial pharmaceutical companies. Interaction between commercial companies, scientists, and drug-regulatory agencies has defined the steps necessary for development of a safe, acceptable, and economically feasible product. Expected financial returns from sales of the final product have driven the development process.

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