Sohji Nagase, MD, PhD, Department of Internal Medicine, Institute of Clinical Medicine, University of Tsukuba, 1-1-1 Ten-nodai, Tsukuba, Ibaraki 305 (Japan), Tel/Fax +81 (298) 53-3202, E-Mail [email protected] Dear Sir, We read with great interest the report by Dr. Rivas-Cabañero et al. [1] published as a letter to the editor in Nephron last year. The authors found that nitrite and nitra...

Hymenopterous parasitoids of filth flies (Diptera: Muscidae) were surveyed during 2 years on dairy farms in Ontario and Quebec near Ottawa, Ontario, using freeze-killed sentinel house fly (Musca domestica L.) pupae and naturally occurring fly pupae collected on site. Musca domestica and Stomoxys calcitrans (L.) (stable fly) represented 98.3% of the natural fly hosts from which parasitoids emerg...

Week-old wheat seedlings absorbed at least 40% NO3from NaNO3 when preloaded with K+ than when preloaded with Na+ or Ca2". Cultures of Tnticum vulgare L. cv. Arthur were grown for 5 days on 0.2 ,M CaSO4, pretreated for 48 hours with either 1 mM CaSO4, K2SO4, or Na2SO4, and then transferred to 1 mM NaNO3. All solutions contained 0.2 mM CaSO4. Shoots of K+-preloaded plants accumulated three times ...

The effect of the heavy metals copper and cadmium on natural bacterial populations of surface microlayer and subsurface water was investigated. Two parameters, number of colony-forming bacteria and 14C-glucose uptake rate, were evaluated. The 2 natural bacterial populations showed different responses to the heavy metals. Results support the existence of autochthonous bacterioneuston populations...

The amount of magnetite (Fe304) within mag­ netosomes of the microaerophilic bacterium AquQspirillum magnetotacticum varies with oxygen and nitrogen supply. The development of optical methods for directly measuring cell magnetism in culture samples has enabled us to quantitate bacterial Fe304 yields. We measured final cell yields. average cell magnetic moments, and magnetosome Yields of growing...

Denitrification may represent an important mechanism in the fate of N applied to turf. Denitrification losses were directly measured from fertilized 'Baron' Kentucky bluegrass (Poa pratensis L.) sod samples sealed in acrylic chambers using the acetylene inhibition technique. Losses were correlated with soil texture, percent soil sat· uration (SAT), and temperature. Losses from turf on a Hadley ...

A mathematical model is presented for the galvanostatic deposition of Ni(OH)2 films in stagnant Ni(NO,), solutions. The objective is to quantify the anomalous deposition behavior reported previously in which the utilization of the electrochemically generated OW species decreased drastically as the concentration of Ni(N03)2 increased beyond 0.1 M. For example, as the Ni(NO,)2 concentration incre...

Rates of sulfate reduction and denitrification were measured in the sediments of unacidified, experimentally acidified, and atmospherically acidified lakes in North America and Norway. These data, plus profiles of porewater and sediment chemistry, demonstrated that in all of the lakes Hb was being actively consumed by both sulfate reducers and denitrifiers. Both of these microbial activities we...

We characterized structural and functional attributes along hills lope gradients in headwater catchments. We endeavored to identify parameters that described significant transitions along the hills lope. On each of four catchments, we installed eight 50 m transects perpendicular to the stream. Structural attributes included woody and herbaceous vegetation; woody debris and forest floor mass, ni...

The response of the marine diatom Phaeodactylum ,tricornutum to Fe deficiency was evaluated in the context of fundamental physiological models of growth and photosynthesis. Fe deficiency induced chlorosis, which decreased Chl a : C ratios and Chl a-specific light-saturated photosynthesis (P,“). In contrast to Pme, (Ye was slightly increased under Fe deficiency, and photosynthesis in Fedeficient...