IRAS 14348-1447, an Ultraluminous Pair of Colliding, Gas-Rich Galaxies: The Birth of a Quasar?

Ground-based observations of the object IRAS 14348-1447, which was discovered with the Infrared Astronomical Satellite, show that it is an extremely luminous colliding galaxy system that emits more than 95 percent of its energy at far-infrared wavelengths. IRAS 14348-1447, which is receeding from the sun at 8 percent of the speed of light, has a bolometric luminosity more than 100 times larger than that of our galaxy, and is therefore as luminous as optical quasars. New optical, infrared, and spectroscopic measurements suggest that the dominant luminosity source is a dustenshrouded quasar. The fuel for the intense activity is an enormous supply of molecular gas. Carbon monoxide emission has been detected at a wavelength of 2.6 millimeters by means of a new, more sensitive receiver recently installed on the 12-meter telescope of the National Radio Astronomy Observatory. IRAS 14348-1447 is the most distant and luminous source of carbon monoxide line emission yet detected. The derived mass of interstellar molecular hydrogen is 6 x 10(10) solar masses. This value is approximately 20 times that of the molecular gas content of the Milky Way and is similar to the largest masses of atomic hydrogen found in galaxies. A large mass of molecular gas may be a prerequisite for the formation of quasars during strong galactic collisions.     

A short circuit in thermohaline circulation: A cause for northern hemisphere glaciation?

The cause of Northern Hemisphere glaciation about 3 million years ago remains uncertain. Closing the Panamanian Isthmus increased thermohaline circulation and enhanced moisture supply to high latitudes, but the accompanying heat would have inhibited ice growth. One possible solution is that enhanced moisture transported to Eurasia also enhanced freshwater delivery to the Arctic via Siberian rivers. Freshwater input to the Arctic would facilitate sea ice formation, increase the albedo, and isolate the high heat capacity of the ocean from the atmosphere. It would also act as a negative feedback on the efficiency of the "conveyor belt" heat pump.     

The pollination of zygogynum (winteraceae) by a moth, sabatinca (micropterigidae): an ancient association?

The primitive and vesselless angiosperm Zygogynum (Winteraceae), which is restricted to New Caledonia, is pollinated by a moth, Sabatinca (Micropterigidae). Fossil records of both the moth and the plant families extend to the Early Cretaceous. Adult Sabatinca have grinding mandibles and usually feed on the spores of ferns and on pollen. The insects use the flowers as mating sites and eat the pollen which is immersed in a dense pollenkitt. This mode of pollination in which flowers serve as mating and feeding stations with floral odors acting as cues may have been common in the early evolution of flowering plants.     

Arabidopsis, the Rosetta stone of flowering time?

Multiple environmental and endogenous inputs regulate when plants flower. The molecular genetic dissection of flowering time control in Arabidopsis has identified an integrated network of pathways that quantitatively control the timing of this developmental switch. This framework provides the basis to understand the evolution of different reproductive strategies and how floral pathways interact through seasonal progression.     

Paleontology. Feathers, or flight of fancy?

On page 2202, researchers describe the 220-million-year-old Longisquama insignis, a squat, mouse-sized reptile with at least six vanelike appendages up to 12 centimeters long sprouting from its spine. The authors argue that the appendages are feathers much like those of modern birds; outside the paper, they have touted the fossil as "an ideal bird ancestor." That conclusion has infuriated paleontologists--not just because it challenges the prevalent theory that birds evolved from theropod dinosaurs, but because they say it does so in an unscientific way.     

Relevance of Dried Meat Product （Kundi）, an Intermediate Moisture Meat,for Food Security

The main goal of food security is for individual to be able to obtain adequate and quality food needed at all times, and to utilise the food to meet the body needs. Kundi is a relish Intermediate Moisture Meat （dried meat） product, produced in the Northern part of Nigeria. 2-3 years old male Camelus dromedarius and White Fulani animals were used for this study, 2 kg of semimembranous muscles from each animal were used, and trimmed of all external fat, connective tissues and bones. Meat samples were cut in sizeable pieces of weight ranges 70-90 grams of 6-8 cm and kept in the refrigerator for 24 hours. Fresh meat cuts were boiled for 20 minutes at 100 ~C, seasoned and oven dried for 3 hours at 170 ~C. This study assessed the proximate composition of fresh and dried meat （Kundi） products and their sensory evaluation in a completely randomized design. The results showed that fresh camel meat had 74.55% and 21.96% significantly （P 〈 0.05） higher in moisture and protein content than 72.69% and 18.96% of fresh beef, while fresh beef had higher （P 〈 0.05） ether extract （6.34%） than fresh camel meat （2.39%）. Laboratory Prepared Beef Kundi （LPBK） had the highest （P 〈 0.05） value in moisture content 35.09% followed by Laboratory Prepared Camel ＇Kundi＇ （LPCK） with 33.21% while Commercial Kundi （CK） had the least. Protein obtained was inversely proportionally to moisture content. Ether extract for LPCK and LPBK were statistically similar （P 〉 0.05） and both were lower （P 〈 0.05） than value obtained for CK. The results obtained for sensory evaluation showed that the panelist rated seasoned Kundi to have the highest significant （P 〈 0.05） valve for tenderness, flavour, colour, juiciness, texture and acceptability with values 6.50, 5.30, 6.50, 6.53, 6.30 and 7.00 respectively. Study showed that dry meat products （Kundi） is of high nutritional qualities, and could be of a great relevance; to food security.     

Investigation and assessment of soil fertility in the greenbelts of Chanba ecological zone of Xi’an, northwestern China

为促进生态化城市建设和保证区域城市的可持续发展,采集西安市浐灞生态区主要地段0～20cm层次土壤,分别测定土壤pH值、有机质、碱解氮、速效磷、速效钾等指标,并采用改进的内梅罗指数对各地段的土壤肥力状况进行综合评价。结果表明：西安市浐灞生态区绿地人为扰动严重,其中：国家湿地公园的土壤肥力属于贫瘠水平;浐河西路、大道（浐灞大道、广运潭大道、欧亚大道）、北辰路、灞河西路、灞柳路、雁鸣湖2号湖湖心岛、雁鸣湖垃圾山、雁鸣湖5号湖预留湿地地段的土壤肥力属于一般水平;雁鸣湖3号湖西岸土壤肥力属于肥沃水平;土壤有机质是浐灞生态区土壤肥力的限制因子。针对上述分析结果,本研究提出了相应的建议和改良措施。     

Sustainability,economies of scale,and social instability: Achilles heel of non-traditional export agriculture?

In this paper I propose a series of hypotheses for further study that are related to potential negative impacts of non-traditional export agriculture (NTEA) on peasantfarmers in Central America. International lenders and donor agencies are promoting this diversification of agricultural exports as part of structural adjustment programs in the region, in order to increase foreign exchange earnings and raise the incomes of the rural poor.There is growing evidence, however, that the impact on the rural poor may not be favorable. I argue that because NTEA can introduce powerful economies of scale, it is likely to accelerate social differentiation in the countryside and expel large numbers of peasant farmers from their lands. In this sense NTEA may be similar to previous export booms, leading to rapid intensification of social instability and conflict in an already troubled region. This raises the serious question of the long term sustainability of this development strategy.