Evaporative temperature and moisture control in a rocking reactor for solid substrate fermentation

Summary In the solid substrate fermentation of cooked yellow corn grits with Rhizopus oligosporus in a rocking drum fermenter, temperature was controlled by blowing air through the substrate, forcing water evaporation. The rate of evaporation was controlled by the relative humidity of the air, according to the rate of heat generation during fermentation. Moisture content was maintained constant by spraying cold water on the substrate regulated by the water balance equation of the system. Both controls were operated by computer programs. The rocking motion in the reactor allowed even distribution of air and water in the substrate without disturbing the growing mycelia.     

Growth, sodium uptake and antioxidant responses of coastal plants differing in their ecological status under increasing salinity

In the present study, we compared the response to salinity of three plants from Brittany coast with contrasted ecological status: Limonium latifolium (salt marshes), Matricaria maritima (beach tops and sand dunes) and Crambe maritima (fixed dunes). Under controlled glasshouse conditions, the growth of the three plants decreased with increasing external salinity. L. latifolium and C. maritima exhibited the highest and lowest resistance to severe salt stress (400 mM), respectively. M. maritima could be considered as an intermediate species, since it tolerated salinity up to 200 mM. The same observation could be made with sodium absorption and acuumulation in plant tissues, the most tolerant species (L. latifolium being the least Na accumulator. Hydrogen peroxide (H₂O₂) and malondialdehyde (MDA), commonly produced in conditions of stress, accumulated significantly in salt treated C. maritima and M. maritima while not in the tolerant L. latifolium. The latter used glutathione reductase to maintain constant H₂O₂ levels under salt stress while peroxidases were very low and ascorbate peroxidase did not respond to salinity stimulation. The medium tolerant halophyte M. maritima used peroxidases to protect from NaCl-induced H₂O₂, while the sensitive C. maritima failed to detoxify H₂O₂ despite a sharp increase in catalase activity. Results showed that the three coastal species differ in resistance to salinity. They also suggested that the level of plant resistance to salinity could be attributed to differing mechanisms to manage the accumulation of sodium and cope with the oxidative damages.     

Livestock First Reached Southern Africa in Two Separate Events

After several decades of research on the subject, we now know when the first livestock reached southern Africa but the question of how they got there remains a contentious topic. Debate centres on whether they were brought with a large migration of Khoe-speakers who originated from East Africa; or whether the livestock were traded down-the-line among hunter-gatherer communities; or indeed whether there was a long history of diverse small scale population movements in this part of the world, one or more of which ‘infiltrated’ livestock into southern Africa. A new analysis of the distribution of stone toolkits from a sizeable sample of sub-equatorial African Later Stone Age sites, coupled with existing knowledge of the distribution of the earliest livestock remains and ceramics vessels, has allowed us to isolate two separate infiltration events that brought the first livestock into southern Africa just over 2000 years ago; one infiltration was along the Atlantic seaboard and another entered the middle reaches of the Limpopo River Basin. These findings agree well with the latest results of genetic research which together indicate that multiple, small-scale infiltrations probably were responsible for bringing the first livestock into southern Africa.     

Generalized linear models with random effects; salamander mating revisited.

In recent years much effort has been devoted to extending regression methodology to non-Gaussian data, where responses are not independent. These methods for dependent responses are suitable for data from longitudinal studies or nested designs. However, use of these methods for crossed designs seems to have serious limitations due to the intensive computations involved because of the intractable nature of the joint distribution. In this paper, we cast the problem in a Bayesian framework and use a Monte Carlo method, the Gibbs sampler, to avoid current computational limitations. The flexibility of this approach is illustrated by analyzing the interesting salamander mating data reported by McCullagh and Nelder (1989, Generalized Linear Models, 2nd edition, London: Chapman and Hall).     

Termination of second trimester pregnancy with laminaria and intramuscular 16 phenoxy-ω-17,18,19,20 tetranor PGE2 methylsuldonylamide (sulprostone) — A randomised study

16 phenoxy-ω-17,18,19,20 tetranor PGE₂ methylsulfonylamide (Sulprostone) was used for termination of second trimester pregnancy in four groups of 30 patients. The drug was administered in intramuscular doses of either 0.5 mg four hourly or 1.0 mg 8 hourly. In two groups of 30 patients a medium size sterile laminaria was inserted into the cervical canal eight hours before the start of prostaglandin treatment. In the group treated with 1.0 mg sulprostone eight hourly, 96.7% of those with laminaria and 86.7% without laminaria aborted in respective mean times of 11.2 hrs and 17.5 hrs. All 30 patients (100%) in the laminaria group treated with 0.5 mg sulprostone four hourly aborted within 30 hours in a mean time of 10.4 hours compared with 26 patients (86.7%) in a mean time of 16.7 hours in the group without laminaria.One patient receiving 0.5 mg sulprostone four hourly (no laminaria) sustained a cervical tear requiring repair. The incidence of nausea, vomiting, diarrhoea, cold and shivering was low and similar in the four groups.     

Cyclic AMP regulation of Gs protein. Thyrotropin and forskolin increase the quantity of stimulatory guanine nucleotide-binding proteins in cultured thyroid follicles

This study was carried out to clarify the way in which thyrotropin (TSH) and forskolin regulate the adenylylcyclase complex in thyroid follicle cells. We examined the effects of chronic treatment of pig thyroid follicles with TSH or forskolin on the state of G proteins by (a) assaying adenylylcyclase activity, (b) analyzing the ADP-ribosylation of stimulatory G protein (Gs) by cholera toxin, and (c) quantifying the Gs subunits by Western blotting with antipeptide antibodies. Chronic exposure (18 h) of thyroid follicles to a low concentration of TSH (0.01-0.1 milliunit/ml) enhanced the subsequent response of adenylylcyclase to TSH. Higher concentration of TSH (1 milliunit/ml) induced a homologous desensitization of this response. In cells pretreated with forskolin, the TSH-stimulated adenylylcyclase activity was higher than in control cells. The forskolin-or guanosine 5'-(beta, gamma-imido) triphosphate (Gpp(NH)p)-stimulated adenylylcyclase activity was always significantly increased after chronic treatment of cells with TSH or forskolin. Treatment of cultured thyroid follicle membranes with [32P]NAD and cholera toxin resulted in labeling of the Gs alpha (45-52-kDa) component. Culturing follicles with TSH (0.001-1 milliunit/ml) or forskolin (0.01-10 microM) greatly affected the cholera toxin-mediated ADP-ribosylation of the Gs alpha subunit. Gs alpha labeling increased progressively to level off at 1 milliunit/ml TSH or 1 microM forskolin (150-200%). Gs alpha immunoreactivity was increased in parallel (200-300%). The immunoreactivity of G beta subunits in cells cultured with TSH or forskolin was also increased compared with control cells. Cycloheximide abolished the effects of TSH and forskolin on the follicles, suggesting that new protein synthesis is required. These results indicate that Gs protein subunits are up-regulated by TSH and forskolin and suggest that their synthesis in thyroid cells is mediated, at least in part, by a cyclic AMP-dependent mechanism.     

Synteny mapping in river buffalo

The cosegregation of ten coding loci has been investigated, in a panel of 37 somatic cell hybrids resulting from the fusion of a hamster cell line and river buffalo lymphocytes, by use of Southern hybridization technique. Five syntenic groups, TCRB-PGY3, ASS-ABL, FUCA1P-CRYG, MBP-YES1, and CGN1-ACTA1, previously assigned to cattle as U13, U16, U17, U28, and U29 respectively, were also found to be syntenic in buffalo. Based on the extensive syntenic conservation and banding homology between cattle and river buffalo, comparative mapping predicts the localization of these syntenic groups on river buffalo Chromosomes (Chrs) :BBU7, BBU12, BBU2q, BBU22, and BBU4q respectively as they have been previously localized on cattle Chrs BTA4, BTA11, BTA2, BTA24 & BTA28. Received: 2 April 1996 / Accepted: 4 July 1996