Somali current: evolution of surface flow

The transition of the Somali Current from northeast monsoon conditions to southwest monsoon conditions was observed from April through August 1979. The northeastward flow associated with the Somali Current of the southwest monsoon progressed from the equator in April to 4 degrees N in August. The separation of the current from the coast, as observed at the northern boundary of the northeastward flow, did not intrude north continuously, but rather in distinct steps. South of 4 degrees N, the circulation was characterized by the incorporation of increasing amounts of somewhat more saline water from the south and east into the boundary current. A clockwise gyre with northeastward flow along the coast developed between 6 degrees and 10 degrees N during June.     

Steelhead migration: potential temperature effects as indicated by gill adenosine triphosphatase activities

Yearling steelhead trout held in fresh water at cold temperatures (6.5 degrees or 10 degrees C) showed an increase in gill microsomal Na(+), K(+)-stimulated adenosine triphosphatase activity during parr-smolt transformation, whereas trout held in warm water (15 degrees or 20 degrees C) did not. Adenosine triphosphatase activity increased and other indications of transformation were observed in fish transferred from warm to cold water, whereas the reverse occurred on transfer from cold to warm water.     

Temperature regulation of bacterial activity during the spring bloom in newfoundland coastal waters

While the spring phytoplankton bloom in Newfoundland coastal waters is in progress during April and May, at water temperatures between -1 degrees and +2 degrees C, bacterial growth and respiratory rates remain low. Microbial community respiration is not measurable at -0.2 degrees C. Particulate materials that would be utilized by microorganisms in 2 to 3 days at 20 degrees to 25 degrees C require 11 days at 4 degrees C and 18 days at -0.2 degrees C. Thus, photosynthesis is active but microbial utilization of the products is suppressed. High secondary production in cold water may result from the low rate of microbial decomposition, enabling herbivores to utilize much of the primary production.     

Radio science with voyager 2 at saturn: atmosphere and ionosphere and the masses of mimas, tethys, and iapetus

Voyager 2 radio occultation measurements of Saturn's atmosphere probed to the 1.2-bar pressure level, where the temperature was 143 +/- 6 K and the lapse rate apparently equaled the dry adiabatic value of 0.85 K per kilometer. The tropopause at both mid-latitude occultation locations (36.5 degrees N and 31 degrees S) was at a pressure level of about 70 millibars and a temperature of approximately 82 K. The stratospheric structures were very similar with the temperature rising to about 140 K at the 1-millibar pressure level. The peak electron concentrations sensed were 1.7 x 10(4) and 0.64 x 10(4) per cubic centimeter in the predawn (31 degrees S) and late afternoon (36.5 degrees N) locations. The topside plasma scale heights were about 1000 kilometers for the late afternoon profile, and 260 kilometers for the lower portions and 1100 kilometers for the upper portions of the topside predawn ionosphere. Radio measurements of the masses of Tethys and Iapetus yield (7.55 +/- 0.90) x 10(20) and (18.8 +/- 1.2) x 10(20) kilograms respectively; the Tethys-Mimas resonance theory then provides a derived mass for Afimas of (0.455 +/- 0.054) x 10(20) kilograms. These values for Tethys and Mimas represent major increases from previously accepted ground-based values, and appear to reverse a suggested trend of increasing satellite density with orbital radius in the Saturnian system. Current results suggest the opposite trend, in which the intermediate-sized satellites of Saturn may represent several classes of objects that differ with respect to the relative amounts of water, ammonia, and methane ices incorporated at different temperatures during formation. The anomalously low density of lapetus might then be explained as resulting from a large hydrocarbon content, and its unusually dark surface markings as another manifestation of this same material.     

Deep, zonal subequatorial currents

Large-scale, westward-extending tongues of warm (Pacific) and cold (Atlantic) water are found between 2000 and 3000 meters both north and south of the equator in the Pacific and Atlantic oceans. They are centered at 5 degrees to 8 degrees north and 10 degrees to 15 degrees south (Pacific) and 5 degrees to 8 degrees north and 15 degrees to 20 degrees south (Atlantic). They are separated in both oceans by a contrasting eastward-extending tongue, centered at about 1 degrees to 2 degrees south, in agreement with previous helium isotope observations (Pacific). Thus, the indicated deep tropical westward flows north and south of the equator and eastward flow near the equator may result from more general forcing than the hydrothermal forcing previously hypothesized.     

Hypothalamic Temperature in the Cat during Feeding and Sleep

Anterior hypothalamic temperature is reported for the unanesthetized cat resting at an air temperature of 22 degrees to 25 degrees C during the ingestion of cold or warm liquids, and during sleep. Drinking cold (5 degrees C) milk resulted in an immediate depression of hypothalamic temperature and a period of peripheral vasodilation in the ear and forepaw foot and toe pads, followed by a drop in rectal temperature. Drinking warm (body temperature) milk did not bring about these changes. Hypothalamic temperature during sleep is lower by approximately 0.5 degrees C and is characterized by widely varying, slow-frequency oscillations, compared to the higher, more precisely controlled temperature seen when the animal is awake.     

Venus: preliminary topographic and surface imaging results from the pioneer orbiter

Three large Venus surface features, identified previously in images obtained from Earth-based radar observations, are shown by the Pioneer Venus radar mapper to be elevated 5 to 10 kilometers above the surrounding terrain. Two of these features, one bright and the other dark, lie adjacent to each other astride the 65 degrees N parallel between longitudes 310 degrees E and 10 degrees E. The combined region forms a huge tectonically uplifted plateau, surmounted by radar-bright ridges that may have either a volcanic or tectonic origin. The third feature, located at 30 degrees N, 283 degrees E, is radar-bright and may consist of volcanic material extruded along a fault zone. A first radar-scattering image, compiled from data obtained by the mapper in its imaging mode, shows a region north of the equator; several circular depressions seen in this area may result from meteoritic impact.     

Bentonite debris flows in northern alaska

Seasonal freezing and thawing and the extreme cold of the arctic lead to the development of a variety of characteristic geomorphic features. A new one, bentonite debris flow channels, has been identified near Umiat, Alaska. These flows form when bentonite-rich Cretaceous Shales are exposed to Surface water on slopes of 5 to 30 degrees. The characteristic landform developed is a U-shaped channel 1 to 2 meters deep and from 8 to 10 meters in width. The channel shows a fluted floor and walls and is commonly flanked by a levee. The flow material is appa rently derived from the entire surface of the head portions of associated gullies. When this surface layer hydrates during snowmelt and runoff or during prolonged rain, the bentonite imbibes water and swells to a point at which its viscosity is lowered sufficiently to initiate creep or viscous flow.     

A transient rise in tropical sea surface temperature during the Paleocene-Eocene thermal maximum

The Paleocene-Eocene Thermal Maximum (PETM) has been attributed to a rapid rise in greenhouse gas levels. If so, warming should have occurred at all latitudes, although amplified toward the poles. Existing records reveal an increase in high-latitude sea surface temperatures (SSTs) (8 degrees to 10 degrees C) and in bottom water temperatures (4 degrees to 5 degrees C). To date, however, the character of the tropical SST response during this event remains unconstrained. Here we address this deficiency by using paired oxygen isotope and minor element (magnesium/calcium) ratios of planktonic foraminifera from a tropical Pacific core to estimate changes in SST. Using mixed-layer foraminifera, we found that the combined proxies imply a 4 degrees to 5 degrees C rise in Pacific SST during the PETM. These results would necessitate a rise in atmospheric pCO2 to levels three to four times as high as those estimated for the late Paleocene.     

分蘖期冷水胁迫对寒地粳稻根系生理特性及产量的影响

试验以东农428和松粳10为供试材料,于2018年在东北农业大学阿城实验实习基地开展分蘖期不同天数(0、5、10、15 d)冷水灌溉处理试验,分析分蘖期冷水灌溉对寒地粳稻根系活力、抗氧化系统、渗透调节物质含量、内源激素含量及产量的影响。结果表明,分蘖期冷水灌溉下,寒地粳稻根系SOD、POD、CAT活性和脯氨酸、可溶性糖、可溶性蛋白含量与正常灌溉相比均显著升高,增幅随冷水灌溉时间延长而上升,东农428增幅大于松粳10,但松粳10的O_2~-、H_2O_2和MDA含量增幅大于东农428。冷水灌溉下,两个品种根系内源激素IAA、GA3、ZR含量随冷水胁迫时间延长呈下降趋势,但ABA含量随冷水灌溉时间延长而升高。分蘖期冷水灌溉下,寒地粳稻产量随冷水灌溉天数增加显著下降,松粳10比东农428下降幅度大。     

Hydrothermal vent animals: distribution and biology

Hydrothermal vent communities characterized by large clams, mussels, and vestimentiferan worms thrive on chemosynthetic microbial production. There are similarities in the animal distributions at vent communities from 20 degrees S to 46 degrees N on the Mid-Ocean Ridge in the Pacific Ocean and at cold sulfide seeps in the Gulf of Mexico. Vent communities, consisting of at least 16 previously unknown families of invertebrates, are at least 200 million years old. Since the life-span of a vent is only tens of years, the species survive by rapid growth and widespread dispersal of larvae with the subsequent colonization of new vents.     

Polychlorobiphenyls in North Atlantic ocean water

Concentrations of polychlorobiphenyls (PCB's) have been measured at the surface and at various depths in the water of the North Atlantic Ocean between 26 degrees N and 63 degrees N. The concentrations average about 20 parts per trillion and amount to an estimated 2 x 10(4) metric tons of PCB's in the upper 200 meters of water. The average concentrations of PCB's in the surface water of the Sargasso Sea are lower than those in the northern North Atlantic.     

Body Temperature of Dermochelys coriacea: Warm Turtle from Cold Water

The deep body temperature of a leatherback turtle, Dermochelys coriacea, taken out of cold water, was 18 degrees C above the water temperature. A large size favoring heat retention from muscular activity is probably responsible for this differential. Cooling rates (k) in water, measured on a second animal, were in the order of 0.001 degrees C per minute per degree of difference between body and ambient temperature.     

Forebrain temperature activates behavioral thermoregulatory response in arctic sculpins

Arctic sculpins of the genus Myoxocephalus adapted to water at 5 degrees C escaped from warm water at 20 degrees , 16 degrees , and 12 degrees C when their deep-body temperatures increased from an initial 5 degrees C to about 8 degrees C. Heating parts of the forebrain with water at 25 degrees C circulating through a pair of thermodes astraddle rostral parts of the forebrain shortened the time spent in the warm water and lessened the incease in deep-body temperature before exit from the warm water. Cooling the forebrain to about -1 degrees C caused a large increase in the body temperature and sometimes suppressed the escape from the warm water.     

Temperature and composition of Saturn's polar hot spots and hexagon

Saturn's poles exhibit an unexpected symmetry in hot, cyclonic polar vortices, despite huge seasonal differences in solar flux. The cores of both vortices are depleted in phosphine gas, probably resulting from subsidence of air into the troposphere. The warm cores are present throughout the upper troposphere and stratosphere at both poles. The thermal structure associated with the marked hexagonal polar jet at 77 degrees N has been observed for the first time. Both the warm cyclonic belt at 79 degrees N and the cold anticyclonic zone at 75 degrees N exhibit the hexagonal structure.     

库尔勒香梨枝条、花芽冻害发生程度与相关生理指标研究

2008年1月下旬库尔勒地区的梨树遭受不同程度的冻害,以了解受不同程度冻害的香梨枝条、花芽相关生理指标为目的,以不同冻害程度的枝条、花芽为试验材料,测定其部分生理及营养元素指标,并对不同程度冻害与各指标的关系进行研究。结果表明,随着冻害程度的不断加深,枝条和花芽的游离脯氨酸、可溶性糖含量不断降低,并且差异显著,POD活性、MDA含量变化不具有一致性,因此,游离脯氨酸、可溶性糖含量可作为库尔勒香梨树的主要抗冻生理指标。随着冻害程度的不断加深,枝条和花芽的N,K,Mg含量不断降低,并且差异显著,Ca含量变化不具有一致性,P含量差异不明显,因此,N,K,Mg含量可作为库尔勒香梨树的主要抗冻营养元素指标。     

不同处理方法对小白菜硝酸盐含量的影响

在不同氮水平条件下（5,10,15,20mmol／L4个氮浓度梯度,分别用N1、N2、N3和N4表示）,采用水培方法研究新鲜和漂烫的小白菜在室温和冷藏条件下的硝酸盐含量变化。结果表明：①低氮水平N1和N2,在室温条件下,新鲜小白菜硝酸盐含量随放置时间基本不变,而冷藏条件下,有所增加;高氮水平N3和N4条件下,无论是室温还是冷藏,新鲜小白菜硝酸盐含量均呈先微增后下降的变化趋势。当室温放置48h时,N3、N4处理的硝酸盐含量分别下降16．8％和23．0％,而冷藏放置48h时,分别下降21．2％和18．0％。②低氮水平N1和N2条件下,无论在室温还是冷藏漂烫小白菜硝酸盐含量基本不随放置时间而变化;高氮水平N3和N4条件下,其含量总体呈下降趋势,室温放置48h时,N3、N4处理的硝酸盐含量分别下降5．2％和33．1％,而冷藏48h时,分别下降10．0％和27．9％。③冷藏新鲜和漂烫小白菜硝酸盐含量均高于室温含量。④在N4、N3、N2、N1处理中,新鲜小白菜硝酸盐含量分别是漂烫小白菜的2．43倍、3．08倍、10．04倍、2．78倍。漂烫可显著减少小白菜的硝酸盐含量。     

Increase in the stratospheric background sulfuric Acid aerosol mass in the past 10 years

Data obtained from measurements of the stratospheric aerosol at Laramie, Wyoming (41 degrees N), indicate that the background or nonvolcanic stratospheric sulfuric acid aerosol mass at northern mid-latitudes has increased by about 5 +/- 2 percent per year during the past 10 years. Whether this increase is natural or anthropogenic could not be determined at this time because of inadequate information on sulfur sources, in particular, carbonyl sulfide, which is thought to be the dominant nonvolcanic source of stratospheric sulfuric acid vapor. An increase in stratospheric sulfate levels has important climatic implications as well as heterogeneous chemical effects that may alter the concentration of stratospheric ozone.     

Controls on the preservation of biogenic opal in sediments of the eastern tropical pacific

A map of the preservation pattern of siliceous microfossils was constructed from an examination of 125 piston and gravity cores of Quaternary sediments from throughout the eastern tropical Pacific. Preservation is enhanced where high surface water productivity supplies a high input rate of siliceous tests to the sea floor, except in a large area north of 5 degrees N, east of the East Pacific Rise. Here a high input rate of terrigenous silicates may adversely affect preservation of biogenic opal in the sea-floor sediments.     

Microorganisms in the accreted ice of Lake Vostok, Antarctica

Analysis of a portion of Vostok ice core number 5G, which is thought to contain frozen water derived from Lake Vostok, Antarctica (a body of liquid water located beneath about 4 kilometers of glacial ice), revealed between 2 x 10(2) and 3 x 10(2) bacterial cells per milliliter and low concentrations of potential growth nutrients. Lipopolysaccharide (a Gram-negative bacterial cell biomarker) was also detected at concentrations consistent with the cell enumeration data, which suggests a predominance of Gram-negative bacteria. At least a portion of the microbial assemblage was viable, as determined by the respiration of carbon-14-labeled acetate and glucose substrates during incubations at 3 degrees C and 1 atmosphere. These accreted ice data suggest that Lake Vostok may contain viable microorganisms.