Different Ways of Hydrogen Bonding in Water - Why Does Warm Water Freeze Faster than Cold Water?

2016 ◽  
Vol 13 (1) ◽  
pp. 55-76 ◽  
Author(s):  
Yunwen Tao ◽  
Wenli Zou ◽  
Junteng Jia ◽  
Wei Li ◽  
Dieter Cremer
2020 ◽  
Vol 642 ◽  
pp. 133-146
Author(s):  
PC González-Espinosa ◽  
SD Donner

Warm-water growth and survival of corals are constrained by a set of environmental conditions such as temperature, light, nutrient levels and salinity. Water temperatures of 1 to 2°C above the usual summer maximum can trigger a phenomenon known as coral bleaching, whereby disruption of the symbiosis between coral and dinoflagellate micro-algae, living within the coral tissue, reveals the white skeleton of coral. Anomalously cold water can also lead to coral bleaching but has been the subject of limited research. Although cold-water bleaching events are less common, they can produce similar impacts on coral reefs as warm-water events. In this study, we explored the effect of temperature and light on the likelihood of cold-water coral bleaching from 1998-2017 using available bleaching observations from the Eastern Tropical Pacific and the Florida Keys. Using satellite-derived sea surface temperature, photosynthetically available radiation and light attenuation data, cold temperature and light exposure metrics were developed and then tested against the bleaching observations using logistic regression. The results show that cold-water bleaching can be best predicted with an accumulated cold-temperature metric, i.e. ‘degree cooling weeks’, analogous to the heat stress metric ‘degree heating weeks’, with high accuracy (90%) and fewer Type I and Type II errors in comparison with other models. Although light, when also considered, improved prediction accuracy, we found that the most reliable framework for cold-water bleaching prediction may be based solely on cold-temperature exposure.


1973 ◽  
Vol 133 (4) ◽  
pp. 735-738 ◽  
Author(s):  
Ian A. Johnston ◽  
Neil Frearson ◽  
Geoffrey Goldspink

1. Myofibrillar adenosine triphosphatase (ATPase) activities were measured for white myotomal muscle of 19 species of fish. 2. The activity was measured at different temperatures and after periods of preincubation at 37°C. 3. The inactivation half-life at 37°C depended on environmental temperature, increasing as the temperature increased. 4. Cold-water fish had higher myofibrillar adenosine triphosphatase activity at low temperatures than had warm-water fish. 5. The significance of these results is discussed.


2018 ◽  
Vol 10 (1) ◽  
Author(s):  
Mark Ayzenberg ◽  
Michael Narvaez ◽  
James Raphael

Casting is routinely used for acute andpost-operative immobilization and remains a cornerstone in the non-operative management of fractures and deformities. Theapplication of a properly fitted and well-molded cast, especially for a trainee, can bechallenging. We present a simple method ofprolonging cure time of fiberglass cast — placing ice in the dip water. Eight-ply, five-inch fiberglass cast was circumferentially applied to an aluminum-wrapped cardboard cylinder. An electronic, 2-channel temperature sensor (TR-71wf Temp Logger, T&D Corporation, Matsumoto, Japan), accurateto 0.1ºC and accurate to ±0.3ºC, was placed between the fourth and fifth layers of fiberglass. Thirty total casts were tested using 9±1ºC (cold), 22±1ºC (ambient), and 36±1ºC (warm) dip water. Room temperature was maintained at 24±1ºC. Cast temperatures were measured during theexothermic reaction generated by the castcuring. Peak temperatures and cure timeswere recorded. Cure time was defined as the point of downward deflection on the time-temperature curve immediately after peak. Cure and peak temperatures were compared among groups using analysis of variance. Mean cure time was 3.5±0.1 minutes forwarm water, 5.0±0.4 minutes for ambient water and 7.0±0.5 minutes for cold water. Peak temperature, measured between layers 4 and 5 of the cast material, was 36.6±0.8ºC for warm water, 31.1±1.4ºC for ambient water and 25.2±0.5ºC for cold water. Cold afforded, on average, an additional 2 minutes (40% increase) in cure time compared to ambient water and an additional 3.5 minutes (100% increase) compared to warm water. Cure time differences were significant (P<0.001) for all groups, as were peak temperature differences (P<0.001). Temperatures concerning for development of burns were never reached. Utilizing iceddip water when casting is a simple andeffective method to prolong the time available for cast application. Orthopedic residents and trainees may find this useful in learning to fabricate a high quality cast. For the experienced orthopedic surgeon, this method eliminates the need to bridge long-limb casts and facilitates the application of complex casts.


2020 ◽  
Vol 45 (7) ◽  
pp. 563-572
Author(s):  
Kristen E Kay ◽  
Laura E Martin ◽  
Kimberly F James ◽  
Sashel M Haygood ◽  
Ann-Marie Torregrossa

Abstract Increasing evidence suggests that stimulus temperature modifies taste signaling. However, understanding how temperature modifies taste-driven behavior is difficult to separate as we must first understand how temperature alone modifies behavior. Previous work has suggested that cold water is more rewarding and “satiating” than warm water, and water above orolingual temperature is avoided in brief-access testing. We explored the strength of cold water preference and warm water avoidance by asking: (1) if cold temperature alone was sufficient to condition a flavor preference and (2) if avoidance of warm stimuli is driven by novelty. We addressed these questions using custom-designed equipment that allows us to monitor and maintain solution temperatures. We conducted two-bottle preference tests, after pairing Kool-Aid flavors with 10 or 40 °C. Rats preferred the flavor paired with cold temperature, both while it was cold and for 1 day while solutions were presented at 22 °C. We then examined the role of novelty in avoidance of 40 °C. Rats were maintained on 10, 22, or 40 °C water in their home cage to increase familiarity with the temperatures. Rats were then subject to a series of brief-access taste tests to water or sucrose at 10 to 40 °C. Rats that had 40 °C experience licked more to 40 °C water, but not sucrose, during brief-access testing. In a series of two-bottle preference tests, rats maintained on 40 °C water had a decreased preference for 10 °C water when paired opposite 40 °C water. Together, these data contribute to our understanding of orosensory-driven behavior with water at different temperatures.


1987 ◽  
Vol 24 (4) ◽  
pp. 643-653 ◽  
Author(s):  
Alexander D. McCracken ◽  
Alfred C. Lenz

Ordovician conodont faunas from the fine-grained clastic Road River Group in northern Yukon Territory contain a mixture of species from both warm- and cold-water regions. This group in southwestern Northwest Territories also has mixed faunas, whereas conodonts from the carbonate facies are more characteristic of the warm-water regions.Six conodont associations and biozones are identified from the Yukon. Some, such as the early Llanvirn "Cordylodus" horridus – Spinodus spinatus association, contain reworked elements. The Pygodus serra Zone (middle–late Llanvirn) is within the upper P. tentaculatus Zone and well below the G. euglyphus Zone. Genera include Ansella, Periodon, Protopanderodus, Pygodus, and Walliserodus.At Peel River, conodonts are within the P. pacificus Zone. The Blackstone River conodonts occur above the P. pacificus Zone and below the G. persculptus Zone (?) and include Oulodus rohneri, Plectodina florida, and Noixodontus. Amorphognathus ordovicicus, Gamachignathus ensifer, O. ulrichi, and Plectodina tenuis occur in both faunas. These represent Fauna 12, found in late Richmondian strata, rather than the Gamachian Fauna 13 and are assigned to the G. ensifer Zone; both occurrences of G. ensifer are biohorizons. The C.? extraordinarius and G. persculptus zones are not recognized at Peel and Rock rivers and Tetlit Creek.The Ozarkodina n. sp. A – Icriodella sp. B association occurs at Pat Lake between the G. persculptus Zone (?) and the underlying P. pacificus Zone. The Ozarkodina have a Silurian aspect but must be regarded as Ordovician.The Ordovician–Silurian boundary in the Road River Group of the Yukon is best defined using graptolites because of the rare occurrence of conodonts.


1933 ◽  
Vol 8 (1) ◽  
pp. 433-458 ◽  
Author(s):  
R. A. McKENZIE

From 1925 to 1933 inclusive, during the summer season, 8,774 cod were tagged at eight points along the coasts of Nova Scotia and Prince Edward Island and eight per cent were recaptured during the following years, none after the sixth.Cod performing a restricted migration (less than 40 kilometres) were found to be in the majority off Halifax from July to September and off Shelburne in June and August in certain areas.Near Seal island in June, off Shelburne in July and September, and off Glace Bay in July and August, the majority of the cod were found to show orderly extended migrations. In the first two instances this movement was shoreward in the summer and seaward to about 130 metres in the early winter. The Glace Bay cod moved from the offshore banks just west of the Laurentian channel to the Cape Breton vicinity in the summer, returning early in the winter.A small percentage of the various stocks of cod performed roving migrations.The complete forsaking of the Cape Breton district for the offshore banks in the winter is attributed to the unfavourable ice cold water, while south-westward of Canso the movement off shore is thought to be caused by the very warm water inshore in the autumn and continued through the influence of the cold inshore waters several months later.As they grow older, the Shelburne cod remain progressively a little farther off shore when they move to shoal water each summer.


2005 ◽  
Vol 98 (4) ◽  
pp. 1334-1340 ◽  
Author(s):  
Catherine O'Brien

Cold-induced vasodilation (CIVD) is a cyclic oscillation in blood flow that occurs in the extremities on cold exposure and that is likely associated with reduced risk of cold injury (e.g., frostbite) as well as improved manual dexterity and less pain while working in the cold. The CIVD response varies between individuals, but the within-subject reproducibility has not been adequately described. The purpose of this study was to quantify the within-subject variability in the CIVD response under standardized conditions. Twenty-one volunteers resting in a controlled environment (27°C) immersed the middle finger in warm water (42°C) for 15 min to standardize initial finger temperature and then in cold water (4°C; CWI) for 30 min, on five separate occasions. Skin temperature (Tf) and blood flow (laser-Doppler; expressed as percent change from warm-water peak) responses that describe CIVD were identified, including initial nadir reached during CWI, onset time of CIVD, initial apex during CIVD, time of that apex, and overall mean during CWI. Within-subject coefficient of variation for Tfacross the five tests for the nail bed and pad, respectively, were as follows: nadir, 9 and 21%; onset, 18 and 19%; apex, 12 and 17%; apex time, 23 and 24%; mean 10 and 15%. For blood flow, these values were as follows: nadir 52 and 64%; onset, 6 and 5%; apex, 33 and 31%; apex time 9 and 8%; and mean 43 and 34%. Greater variability was found in the temperature response of the finger pad than the nail bed, but for blood flow the variability was similar between locations. Variability in onset and apex time between sites was similar for both temperature and blood flow responses. The reproducibility of the time course of CIVD suggests this methodology may be of value for further studies examining the mechanism of the response.


2021 ◽  
Vol 2 (2) ◽  
pp. 182-187
Author(s):  
J. M. Olomu

THE effectiveness of using maize starch, warm water, cold water, groundnut oil, palm oil and cold storage [refrigerator] in preserving the quality of eggs was studied. Groundnut oil, palm oil and cold storage were equally effective in preserving the quality of eggs while maize starch, cold water and warm water were found ineffective. The effectiveness of palm oil and groundnut oil was further enhanced when the oil-treated eggs were stored in the refrigerator for four weeks. Treatment with groundnut oil for one minute before storage for four weeks was considered the preferred method of preserving the quality of eggs.


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