On a Polynya in Makinson Inlet

A polynya was observed three kilometres south of Hook Glacier in the northwest arm of Makinson Inlet in May 1973 .... it was only possible to occupy four stations in the arm: Station I near the head, Station 2 in the basin just north of Hook Island, Station 3 about 200 m east of the polynya and Station 4 east of St. Laurent Point .... The results from Station 2 showed that the water was almost isothermal at -1.80 °C, near the freezing point, with little salinity variation in the vertical column. The temperature at 125 m in Station 2 was nearly 0.5 °C lower than the temperature at the same depth in Station 4 in the waters of the main section of the inlet. ... The resulting estimated volume of water in the inlet is 2.4 × 10**9 m³ which is considered accurate only to within a factor of three. ... The estimated cross-sectional area, 1.5 × 10**4 m² is probably accurate to a factor of 2. ... The mean value adopted for the volume of the tidal prism, 1.2 × 10**8 m³, is probably accurate to a factor of 2. The rate of loss of heat through the surface of the polynya can be estimated to be about 1000 langleys per day if the air temperature is taken as -30 °C, the water temperature as -1 °C and the mean wind velocity 5 m/sec. This gives a total heat loss during each flood tide over the 2 km² of the polynya of 5 × 10**12 calories. It is assumed that more or less complete mixing of the incoming tidal flow and the waters of the arm takes place on each flood tide. This assumption is justified, as a first approximation at least, by the state of homogeneity revealed by temperature and salinity observations. The resulting degree of cooling of the water in the arm would then be 3.0 × 10**-3 °C on each flood tide. If now it is assumed that the water in the arm had a similar temperature structure to that in the main inlet at the beginning of freeze-up, the difference between the average temperature in the deep basin and that in the main inlet in May must be due to additional cooling of the inflowing water as it passes through the polynya. By integration over the upper 150 m, this mean temperature difference is found to be about 0.2 °C, and therefore under the assumed conditions about 70 tides would be required to give the observed cooling, or about 1000 degree-days. ... the observed temperature distribution could be expected to occur some time in December. Until this time the polynya would remain open because of the flow on both flood and ebb tides of water above the freezing point. Once the water in the basin reached an isothermal condition with the temperature at -1.7 °C or lower, it might be expected that the very cold waters of the ebb tide would begin to freeze in the polynya. On each flood tide slightly warmer water mixed upwards from the deeper levels of the main inlet would pass through the polynya but the low temperatures of January and February and the large net heat loss due to radiation would probably be sufficient to keep the surface frozen over. With the return of the sun in April, the combination of solar heating and of ablation from below by the slightly warmer inflowing water would be expected to open the polynya sometime before the rest of the ice in the inlet broke up. When the observations were made in the middle of May the polynya was about 2 km long north to south and 1 km wide. The ice in that region of the arm even at some distance from the open water was about one third the thickness of that in the main inlet and about half the thickness of that in the basin .... ERTS satellite photographs taken in 1973 show that the polynya opened some time between 4 April and 22 April, at which latter date it had a diameter of about 1 km. The ice cover around it remained continuous until July. ... In summary, the water in the basin is well mixed right to the bottom, although the sill depth is less than 15 m. At the same time the polynya region appears to remain open for most of the year. The conclusion is that the two phenomena are complementary and that the homogeneity of the water is a result of the downward mixing of water cooled in its passage through the polynya. Whether the water behind the sill becomes stratified during the summer and consequently becomes partly deoxygenated at depth remains to be determined. However, it seems probable that even if this happens there is complete regeneration of the deep basin water at least every winter. ..

Fresh Water Anchor Ice Along an Arctic Beach

Anchor ice is broadly defined ... as "submerged ice attached or anchored to the bottom, irrespective of the nature of its formation". We discuss here a form of anchor ice of which we can find no previous description. During August 1978 and 1979 we observed a belt of fresh-water anchor ice along 30 km of beach between Sheringham Point and Prospect Hills in southwest Cornwallis Island, N.W.T. ..

Fresh Water Anchor Ice Along an Arctic Beach

Anchor ice is broadly defined ... as "submerged ice attached or anchored to the bottom, irrespective of the nature of its formation". We discuss here a form of anchor ice of which we can find no previous description. During August 1978 and 1979 we observed a belt of fresh-water anchor ice along 30 km of beach between Sheringham Point and Prospect Hills in southwest Cornwallis Island, N.W.T. ..

Tidal Remnants and Intergalactic HII Regions

We report the discovery of two small intergalactic HII regions in the loose group of galaxies around the field elliptical NGC 1490. The HII regions are located at least 100 kpc from any optical galaxy but are associated with a number of large HI clouds that are lying along an arc 500 kpc in length and that have no optical counterpart on the Digital Sky Survey. The sum of the HI masses of the clouds is almost 10^10 M_sun and the largest HI cloud is about 100 kpc in size. Deep optical imaging reveals a very low surface brightness counterpart to this largest HI cloud, making this one of the HI richest optical galaxies known (M_HI/L_V~200). Spectroscopy of the HII regions indicates that the abundance in these HII regions is only slightly sub-solar, excluding a primordial origin of the HI clouds. The HI clouds are perhaps remnants resulting from the tidal disruption of a reasonably sized galaxy, probably quite some time ago, by the loose group to which NGC1490 belongs. Alternatively, they are remnants of the merger that created the field elliptical NGC1490. The isolated HII regions show that star formation on a very small scale can occur in intergalactic space in gas drawn from galaxies by tidal interactions. Many such intergalactic small star formation regions may exist near tidally interacting galaxies.Comment: To appear in the proceedings of the IAU Symposium #217, Recycling Intergalactic and Interstellar Matter, eds. P.-A. Duc, J. Braine, and E. Brinks, 6 pages with low resolution figures. The full paper with high resolution images can be downloaded from http://www.astron.nl/~morganti/Papers/cloud.ps.g

Recoil Ranges of Nuclei Produced in Proton-Induced Reactions

This work was supported by National Science Foundation Grant PHY 76-84033 and Indiana Universit

The preparation of a Non-Desiccated Sodium Caseinate Sol and its use in ice cream

1. The body and texture of ice cream are improved by the replacement of dry skimmilk by sodium caseinate sols. This improvement was shown up to 2.5 to 5.0 percent replacement, depending on the composition of the mix. 2. The flavor of ice cream was progressively improved by the replacement of dry skimmilk by sodium caseinate sols up to 3 to 4 percent replacement, depending on the composition of the mix. 3. This flavor improvement was due to the careful pH control used in the preparation of the sodium caseinate sols. 4. The type of melting of the ice cream was altered by the replacement of dry skimmilk by sodium caseinate sols. 5. The use of sodium caseinate sols increased the initial and maximum overrun and decreased the whipping time of the ice creams produced. 6. The curves for whipping time show that from 1.5 to 3.0 percent replacement of dry skimmilk by the sodium caseinate sols is necessary to effect sufficient improvement in whip to warrant their use. A 3 percent replacement would be necessary with a mix containing 14 percent fat and 10 percent serum solids. 7. The use of sodium caseinate preparations as additional solids, i.e., in addition to the amounts of serum solids (8 to 10 percent) commonly used by the trade, has been suggested. The amounts of milk protein that would be required to yield sufficient improvement in whip and in body and texture score would, in the light of the figures presented, be large enough to make their use questionable

Single versus multiple human-equivalent doses of C. parvum in mice: neutralization of the anti-metastatic effect.

The murine dose of i.v. C. parvum (466 microgram) was compared with a single, low, human-equivalent dose of 70 microgram and with repeated weekly low doses. All treatments increased the antibody titre against C. parvum (CP). However, repeated doses stimulated a much higher titre than single doses. In all treated animals spleen weight peaked at 2 weeks and then fell. A single low dose caused a 3-fold increase, a single high dose or multiple low doses a 6-fold increase. Liver weight changes followed a similar pattern. Hepatosplenomegaly was prolonged by multiple doses. The effects of these treatments on Lewis tumour metastases were studied. A single high dose and a single low dose on the day of tumour implantation (Day 0) were equally effective at inhibiting pulmonary metastases. Repeated low doses starting on Day 0 were no more effective than a single dose. The effect of CP on survival after primary-tumour excision on Day 10 was observed. Low dose CP on Day 7 doubled the harmonic mean of survival time. Repeated doses were no more effective than a single dose. Low-dose prophylaxis up to 2 weeks before tumour significantly inhibited metastases. However, when repeated low-dose prophylaxis was combined with a single low dose on Day 0, the anti-metastatic effect was abrogated. This neutralization of the anti-metastatic effect of CP given on Day 0 was found to persist after a 13-week treatment-free interval. Possible mechanisms for this phenomenon are discussed