Contribution to the biology and geographical distribution of Aegagropila sauteri (Nees) Kutz. [Translation of: Gidrobiologicheskie Zhurnal, Kiev 4(3), 68-69, 1967]

Aegagropila sauteri is a peculiar green algae, the branched thalli of which, according to the amount of growth, forms velvety spheres of a diameter of 3-4, sometimes to 5-6 cm. and bigger. Investigators attribute it to a special genus of green algae. The authors examine Aegagropila sauteri in Lake Markakol (Kazakhstan).

Expanding the Toolkit for Synthetic Biology: Frameworks for Native-like Non-natural Gene Circuits

Synthetic biology combines biological parts from different sources in order to engineer non-native, functional systems. While there is a lot of potential for synthetic biology to revolutionize processes, such as the production of pharmaceuticals, engineering synthetic systems has been challenging. It is oftentimes necessary to explore a large design space to balance the levels of interacting components in the circuit. There are also times where it is desirable to incorporate enzymes that have non-biological functions into a synthetic circuit. Tuning the levels of different components, however, is often restricted to a fixed operating point, and this makes synthetic systems sensitive to changes in the environment. Natural systems are able to respond dynamically to a changing environment by obtaining information relevant to the function of the circuit. This work addresses these problems by establishing frameworks and mechanisms that allow synthetic circuits to communicate with the environment, maintain fixed ratios between components, and potentially add new parts that are outside the realm of current biological function. These frameworks provide a way for synthetic circuits to behave more like natural circuits by enabling a dynamic response, and provide a systematic and rational way to search design space to an experimentally tractable size where likely solutions exist. We hope that the contributions described below will aid in allowing synthetic biology to realize its potential.

Some observations on the temporal variations of size of copepods and some answers to questions on their biology. [Translation from: Internationale Revue der Gesamten Hydrobiologie und Hydrographie 17 99-114, 1927.]

Until now observations on the temporal variation of size of freshwater copepods have not provided much information. Other observers only mention in passing this or that phenomenon from which it is possible to deduct termporal variations. In this study Cyclops strenuus s.l., a freshwater species of fairly wide distribution, is studied in two water bodies. The author studies the systematic, placing of inhabitants described as C. strenuus Fischer in both locations, their annual life cycle, and their annual size variations.

Sensing and Actuation from Biology to Electronics

We introduce an in vitro diagnostic magnetic biosensing platform for immunoassay and nucleic acid detection. The platform has key characteristics for a point-of-use (POU) diagnostic: portability, low-power consumption, low cost, and multiplexing capability. As a demonstration of capabilities, we use this platform for the room temperature, amplification-free detection of a 31 bp DNA oligomer and interferon-gamma (a protein relevant for tuberculosis diagnosis). Reliable assay measurements down to 100 pM for the DNA and 1 pM for the protein are demonstrated. We introduce a novel "magnetic freezing" technique for baseline measurement elimination and to enable spatial multiplexing. We have created a general protocol for adapting integrated circuit (IC) sensors to any of hundreds of commercially available immunoassay kits and custom designed DNA sequences.

We also introduce a method for immunotherapy treatment of malignant gliomas. We utilize leukocytes internalized with immunostimulatory nanoparticle-oligonucleotide conjugates to localize and retain immune cells near the tumor site. As a proof-of-principle, we develop a novel cell imaging and incubation chamber for in vitro magnetic motility experiments. We use the apparatus to demonstrate the controlled movement of magnetically loaded THP-1 leukocytes.

Finally, we introduce an IC transmitter and power ampli er (PA) that utilizes electronic digital infrastructure, sensors, and actuators to self-heal and adapt to process, dynamic, and environmental variation. Traditional IC design has achieved incredible degrees of reliability by ensuring that billions of transistors on a single IC die are all simultaneously functional. Reliability becomes increasingly difficult as the size of a transistor shrinks. Self-healing can mitigate these variations.

Biology of the amphipod Gammarus pulex L. in water-bodies of the Leningrad district, and its piscicultural importance [Translation from: Trudy Vsesoyuznogo Gidrobiologicheskogo Obshchestva 7 99-122, 1956]

Observations and laboratory experiments are summarised that examine the widely discussed issue of what Gammarus pulex feeds on. On the basis of the observations of the authors and data from the literature it can be noted that G. pulex belongs to the omnivorous organisms, but, depending on the conditions of subsistence, in its rations either plant or animal food can predominate.

Water conservation in the city of Pasadena

The object of this report will be to make a complete study of the water that is wasted in the storm drains of Pasadena and determine if there is any practical way of conserving this water.

A study of the reproductive biology of dace in the middle Ob [introduction , summary and table captions only] [Translation from: Trudy tomsk. gos. Univ. 125, pp.77-91]

The Siberian Dace (Leuciscus leuciscus baicalensis (Dyb)is an important trade fish in Siberian waters. In the Ob basin more than 30,000 centners are produced annually. Catches of dace fluctuate significantly both between different rivers and between years in the Tomsk region. Defining the stocks of dace in the waters of the Tomsk region and explaining the fluctuations over time seems to be a very important and relevant question for the workers of the fishing industry. An answer, however, requires an accurate knowledge of the biology of dace; its reproductive, feeding and migration habits and the conditions of wintering etc. In the following we examine one of the above questions i.e. the biology of the reproduction of dace. The study was carried out in the Middle Ob in May 1951. This tranlations provides the introduction, summary and table captions only of the original article.

Changes in feeding biology of Nile tilapia, Oreochromis niloticus (L.), after invasion of water hyacinth, Eichhornia crassipes (Mart.) Solms, in Lake Victoria, Kenya

Oreochrimis niloticus (L.) was introduced to Lake victoria in the 1950s. It remained relatively uncommon in catches until 1965, when the numbers began to increase dramatically. It is now the third most important commercial fish species after the Nile perch, Lates niloticus (L.) and Rastrineobola argentea (Pellegrin). Oreochromis niloticus is considered a herbivore, feeding mostly on algae and plant material. The diet now appears to be more diversified , with insects, fish, algae and plant materials all being important food items. Fish smaller than 5 cm TL have a diverse diet but there is a decline in the importance of zooplankton, the preferred food item of small fish, as fish get larger. The shift in diet could be due to changes which have occurred in the lake. Water hyacinth, Eichhornia crassipes (Mart.) Solms, which harbours numerous insects in its root balls, now has extensively coverage over the lake. The native fish species which preyed on these insects (e.g. haplochromines) have largely been eliminated and O. niloticus could be filling niches previously occupied by these cichlids and non cichlid fishes. The change in diet could also be related to food availability and abundance where the fish is feeding on the most readily available food items.

Reproductive biology of Rastrineobola argentea (Pellegrin) in the northern waters of Lake Victoria

Size at first maturity, breeding periods and condition factor were determined for the small pelagic cyprinid Rastrineobola argentea (Pellegrin) in the Jinja waters of Lake Victoria in 1996-1997. Females showed a reduced size at maturity compared to ten years earlier when exploitation of the species was minimal. The males, however, have changed little. Although the species breeds throughout the year, two breeding peaks were observed during the drier months of August and December-January. Minimal breeding was observed in the rainy months of April-May and October-November. Fish from the open water station at Bugaia showed a higher proportion of breeding individuals than those from inshore areas. The mean monthly condition factor of fish from Napoleon Gulf confirmed breeding peaks obtained from examination of gonad development.

Reproductive biology of Oreochromis niloticus (L.) in the Nyanza Gulf of Lake Victoria

The reproduction of Nile tilapia, Oreochromis niloticus (L.), in the Nyanza Gulf of Lake Victoria was studied from June 1998 to May 1999. Length at maturity ranged from 28-30 cm TL for females and from 32-34 cm TL for males. Males were more abundant in all length classes longer than 36 cm TL. Relative condition factor was above unity, except in August, October and May for males, and October for females. Gonadosomatic index (GSI) was low during the post spawning period (July to October) and high during the protracted breeding period (December-June).

Advisory report on nutrient levels and related ecology of Malham Tarn

Aspects of reported nutrient levels and their ecological implications for Malham Tarn are discussed. Discussion centres upon the data given here as appendices, involving possible evidence of a long-term increase in the concentrations of some nutrients (especially nitrate) of significance for the Tarn's ecology and conservation. Further comparative tests of some methods of chemical analysis employed in obtaining those data are reported.

A survey of aquatic invertebrates of the Somerset Levels, August 13-14, 1981

Since 1975 the wildlife interest of the Somerset Levels and Moors have been assessed. Detailed information has been obtained on the conservation interest of meadows, breeding and wintering bird populations and the botany of aquatic habitats (rhynes). Little work to date has been carried out on the terrestrial and aquatic invertebrate fauna. The prime aim of this survey was to sample a wide variety of rhynes in order to obtain information on the nature and distribution of aquatic invertebrates.