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Magnetotactic bacteria orient and migrate along magnetic field lines in aquatic habitats. The first paper on this phenomenon was written by Richard P. Blakemore (Blakemore, 1975; 1982). In that paper, Blakemore described bacteria collected from a pond in Woods Hole, Massachusetts that migrated persistently northward in the geomagnetic field. He named the behavior “magnetotaxis.” He proposed that northward migration along geomagnetic field lines in the northern hemisphere would cause the bacteria to move downward toward the micro-aerobic or anaerobic zone of the habitat. He also used electron microscopy to show that the bacteria contained nano-scale, iron rich, crystals that he surmised were responsible for magnetotaxis. Blakemore’s papers initiated a vigorous, international, study of magnetotactic bacteria that continues to this day (Schueler, 2007); it has been cited over 650 times in the scientific literature. Recently, two unpublished manuscripts dated 1963 have been found that report on “magnetosensitivity” in aquatic bacteria. The manuscripts, entitled “On a unique behavior of fresh water bacteria” (Bellini, 1963a) and “Further studies on magnetosensitive bacteria” (Bellini, 1963b), were written by Salvatore Bellini, a medical doctor who was working in the Institute of Microbiology at the University of Pavia, Italy. According to Bellini (private communication), he serendipitously discovered the magnetosensitive bacteria in 1958 while examining water samples from sources around Pavia for pathogens. He was encouraged by the institute director (Prof. L. Bianchi) to continue research on the magnetosensitive bacteria; the research program concluded in 1963 with the writing of the two manuscripts. He intended to submit the manuscripts for publication in a scientific journal, but did not receive the necessary permission from a panel of senior faculty who reviewed all research manuscripts from the University before submission. The institute director then encouraged him to send copies of the manuscripts to some universities and research institutions in Italy. Copies of the two manuscripts came into my possession in 2007 via Dr. Henrique Lins de Barros (Brazil) and Prof. Dennis A. Bazylinski (USA). I had the manuscripts translated into English from the original Italian by Ms. Elena Scanu, a native speaker of Italian. I then edited the translations for scientific clarity. To the best of my ability I tried keep the translations as true as possible to Bellini’s original language and meaning. The translations were subsequently sent to Bellini for his review and concurrence. The first manuscript, Bellini 1963a, describes observation of various morphotypes of bacteria in water samples that swam persistently northward and collected at the North edge of water drops on microscope slides. He named this behavior “magnetosensitivity”. Among other things, he observed: a) local magnetic fields produced by bar magnets or small electromagnets could overcome the geomagnetic field and determine the swimming direction of the bacteria in the water drops; b) dead cells oriented in the magnetic field but did not migrate; c) magnetosensitivity was lost in cells enriched in demineralized water, but was restored by addition of soluble iron. On the basis of these observations, he hypothesized that: a) the bacteria contain an internal, biomagnetic dipole; b) the magnetic dipole caused cells to migrate downward in the northern hemisphere toward the less oxygenated bottom sediments; c) magnetosensitive bacteria in the southern hemisphere should swim toward the South magnetic pole; d) the biomagnetic dipole was fashioned from iron compounds. In the second

The oceanic front is a narrow zone in which water properties change abruptly within a short distance. The sea surface temperature (SST) front is an important type of oceanic front, which plays a significant role in many fields including fisheries, the military, and industry. Satellite-derived SST images have been used widely for front detection, although these data are susceptible to influence by many objective factors such as clouds, which can cause missing data and a reduction in front detection accuracy. However, front detection in a single SST image cannot fully reflect its temporal variability and therefore, the long-term mean frequency of occurrence of SST fronts and their gradients are often used to analyze the variations of fronts over time. In this paper, an SST front composite algorithm is proposed that exploits the frontal average gradient and frequency more effectively. Through experiments based on MODIS Terra and Aqua data, we verified that fronts could be distinguished better by using the proposed algorithm. Additionally through its use, we analyzed the monthly variations of fronts in the Bohai, Yellow, and East China Seas, based on Terra data from 2000 to 2013.

In this paper, we introduced parameterizations of the salinity effects (on heat capacity, thermal conductivity, freezing point and saturated vapor pressure) in a lake scheme integrated in the Weather Research and Forecasting model coupled with the Community Land Model (WRF-CLM). This was done to improve temperature simulation over and in a saline lake and to test the contributions of salinity effects on various water properties via sensitivity experiments. The modified lake scheme consists of the lake module in the CLM model, which is the land component of the WRF-CLM model. The Great Salt Lake (GSL) in the USA was selected as the study area. The simulation was performed from September 3, 2001 to September 30, 2002. Our results show that the modified WRF-CLM model that includes the lake scheme considering salinity effects can reasonably simulate temperature over and in the GSL. This model had much greater accuracy than neglecting salinity effects, particularly in a very cold event when that effect alters the freezing point. The salinity effect on saturated vapor pressure can reduce latent heat flux over the lake and make it slightly warmer. The salinity effect on heat capacity can also make lake temperature prone to changes. However, the salinity effect on thermal conductivity was found insignificant in our simulations.

In this paper, we investigated the effects of temperature, oxygen, antioxidants, and corn germ oil on the stability of astaxanthin from Haematococcus pluvialis under different storage conditions, and changes in the composition of astaxanthin esters during storage using high performance liquid chromatography and spectrophotometry. Oxygen and high temperatures (22-25 degrees C) significantly reduced the stability of astaxanthin esters. Corn germ oil and antioxidants (ascorbic acid and vitamin E) failed to protect astaxanthin from oxidation, and actually significantly increased the instability of astaxanthin. A change in the relative composition of astaxanthin esters was observed after 96 weeks of long-term storage. During storage, the relative amounts of free astaxanthin and astaxanthin monoesters declined, while the relative amount of astaxanthin diesters increased. Thus, the ratio of astaxanthin diester to monoester increased, and this ratio could be used to indicate if astaxanthin esters have been properly preserved. If the ratio is greater than 0.2, it suggests that the decrease in astaxanthin content could be higher than 20%. Our results show that storing algal powder from H. pluvialis or other natural astaxanthin products under vacuum and in the dark below 4 degrees C is the most economical and applicable storage method for the large-scale production of astaxanthin from H. pluvialis. This storage method can produce an astaxanthin preservation rate of at least 80% after 96 weeks of storage.

The freshwater cyanobacterium, Cylindrospermopsis raciborskii (Wo’oszynska) Seenayya and Subba Raju is a common species in lakes and reservoirs globally. In some areas of the world it can produce cyto- and hepatotoxins (cylindrospermopsins, saxitoxins), making blooms of this species a serious health concern for humans. In the last 10–15 years, there has been a considerable body of research conducted on the ecology, physiology and toxin production of this species and this paper reviews these studies with a focus on the cylindrospermopsin (CYN)-producing strains. C. raciborskii has low light requirements, close to neutral buoyancy, and a wide temperature tolerance, giving it the capacity to grow in many lentic waterbodies. It also has a flexible strategy with respect to nitrogen (N) utilisation; being able to switch between utilising fixed and atmospheric N as sources of N fluctuate. Additionally this species has a high phosphate (DIP) affinity and storage capacity. Like many cyanobacteria, it also has the capacity to use dissolved organic phosphorus (DOP). Changes in nutrient concentrations, light levels and temperature have also been found to affect production of the toxin CYN by this species. However, optimal toxin production does not necessarily occur when growth rates are optimal. Additionally, different strains of C. raciborskii vary in their cell quota of CYN, making it difficult to predict toxin concentrations, based on C. raciborskii cell densities. In summary, the ecological flexibility of this organism means that controlling blooms of C. raciborskii is a difficult undertaking. However, improved understanding of factors promoting the species and toxin production by genetically capable strains will lead to improved predictive models of blooms.

Rossby waves are the most important waves in the atmosphere and ocean, and are parts of a large-scale system in fluid. The theory and observation show that, they satisfy quasi-geostrophic and quasi-static equilibrium approximations. In this paper, solitary Rossby waves induced by linear topography in barotropic fluids with a shear flow are studied. In order to simplify the problem, the topography is taken as a linear function of latitude variable y, then employing a weakly nonlinear method and a perturbation method, a KdV (Korteweg-de Vries) equation describing evolution of the amplitude of solitary Rossby waves induced by linear topography is derived. The results show that the variation of linear topography can induce the solitary Rossby waves in barotropic fluids with a shear flow, and extend the classical geophysical theory of fluid dynamics.