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A new model is set up to represent the effect of temperature and light on microalgae growth, and predict the productivity of outdoor microalgae based processes. This model includes three cardinal temperatures (T(min), T(opt), and T(max)) and three parameters associated to the light response (μ(max), I(opt) and α). These six parameters have a clear biological meaning which makes model calibration straightforward. An algorithm to estimate both the model parameters and their associated confidence regions is developed. Results show that this model can successfully represent experimental data sets from 15 species cultivated in different experimental conditions. The model predictions, when compared to realistic temperatures recorded in outdoor photobioreactors or raceways, point out a strong decrease of productivity due to over-warming for most commercial species., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

A major increase in the incidence of BP has been recently reported in the United Kingdom. In addition, there are some controversies about the over-mortality of BP patients. The primary objective was to reevaluate the incidence of BP in France as compared with that we estimated 15 years ago. The secondary objective was to assess mortality of BP patients. BP incidence was retrospectively estimated from all BP cases diagnosed between January 2000 and December 2005 in three French regions with a total population of 3.858 million inhabitants. BP mortality was assessed from a prospective cohort accrued during the same time period. A total of 502 incident BP patients (mean age: 82.6±8.8 years) were identified. Overall estimated incidence was 21.7 cases per million persons per year (95%CI:19.8-23.7 cases per million persons per year), which is about 3-fold higher than the incidence that we estimated 15 years ago. In the population aged 70 years or above, BP incidence was 162 cases per million per year (95%CI:147-177 cases per million per year). The overall 1-year survival rate was 62% (95% CI: 56-67%). The risk of death for BP patients was more than six times greater than that for the general population (SMR:6.60; 95%CI:5.47-7.90). The incidence of BP in France has increased 3-fold in the last 15 years. BP is associated with high mortality.

Disseminated superficial actinic porokeratosis was first described by Chernosky and Anderson in 1969. It is characterized by multiple small keratotic lesions on sun-exposed areas beginning in the third of fourth decade. The development of a squamous cell carcinoma within lesions of porokeratosis or the association of superficial actinic porokeratosis with immunosuppression have been well documented. We report the case of a 68-year-old patient who presented actinic porokeratosis associated with rapidly evolutive squamous cell carcinoma of the leg. During the hospitalization, an IgA myeloma was discovered. The authors discuss the relationship between porokeratosis, immunosuppression, and squamous cell carcinoma. Pathogenesis of the lesions is interesting because it is admitted that a keratinocyte clone which carries the porokeratosis abnormality is going to proliferate because of immunosuppression, trauma and infectious diseases. It seems important to search for immunosuppression in patients presenting porokeratosis because the incidence of malignant transformation may increase.

Psoriatic-onycho-pachydermo-periostitis is a particular form of psoriatic arthropathy recently described, which combine psoriatic onychosis, thickening of the distal soft tissues and osteo-periostitis of the distal phalanx without lesion of the interphalangeal joint. Biological examinations are normal. Radiological lesions show a phalanx condensation which gives a spicule aspect. Two cases of onycho-pachydermo-periostitis are described. We report the first one with all the fingers and toes concerned.

Fifteen lactating cows were milked throughout pregnancy, and the effects on milk performance were studied during this period and during the succeeding lactation, relative to 11 conventionally managed cows (2 months dry before calving) as controls. During the last 2 months of pregnancy, only nine cows did not dry off spontaneously. Protein and fat concentrations in milk increased rapidly, but the concentration of lactose, corrected for milk yield, did not change. The ratios of individual caseins to total protein decreased with the quantity of milk produced, but only for yields below approximately 6 kg/d. The relative proportion of kappa-casein tended to decrease in the last milkings. During the succeeding lactation (first 15 weeks after calving and first 6 weeks of grazing) continuously milked cows yielded 4 kg milk/d less than the cows of the other group. The protein content of their milk was higher (2-3 g/kg depending on the period) than that of the control group, and the lactose content tended (P less than 0.10) to be lower. Changes in the relative proportions of nitrogenous fractions with time were not different in the two groups. Differences between the two groups in the concentration of protein in milk, and in the concentration of glucose and non-esterified fatty acids in the plasma, suggest a better energy balance for the continuously milked cows during the succeeding lactation.

Five cows, fitted with rumen and duodenal fistulas, were given ad libitum a small amount of hay and a stable ration of 60 p. 100 maize silage and 40 p. 100 concentrate from 4 weeks before calving of 6 weeks after. The pattern of feeding behaviour and of digestive processes was recorded over the whole period. The following results were obtained: 1) While the amounts of the ingested dry matter of the ratio increased by 40 p. 100, the digestibilities of dry matter, organic matter, crude fiber and starch decreased by an average of 7, 7, 10 and 5 points p. 100 between 2 weeks before calving and the second week after. These values then increased by 3, 3, 3 and 1 points p. 100 between weeks 2 and 6 after calving (fig. 1). 2) The duration of intake and rumination increased rapidly while the rates varied little (fig. 2). At the same time, the number of meals, length of small meals and rumination periods increased, but the length of large meals was minimal around calving time (fig. 3). Consequently, the distribution of intake during the light/dark cycle was modified (fig. 4). 3) The preprandial ammonia content of the rumen liquor was minimal (20 mg/l) the second week of lactation. The volatile fatty acid content and the proportions of different acids varied little throughout the period (fig. 5). 4) The flux of organic matter, non-ammonia nitrogen and starch to the duodenum increased rapidly but the amounts of organic matter digested in the rumen varied little, while those digested in the intestine multiplied almost 3 times, corresponding to a considerable decrease in rumen digestion (table 3, fig. 6). The amino acid composition of duodenal nitrogen varied little between the end of pregnancy and the onset of lactation (table 4).

Feeding behaviour was measured in 12 multiparous dairy cows all day long during the first 5 weeks of lactation. These cows received corn silage ad libitum and concentrates representing 21 to 27% of total dry matter intake, depending on the week. During the first week of lactation, total eating and ruminating times were 364 and 426 min; eating and ruminating rates were 39.0 and 32.5 g DM/min. The feed intake increase during the first 5 weeks of lactation was accompanied by an increase in ruminating time (+ 22%) and eating rate (+ 26%). These two parameters were very sensitive to short-time decreases in DM intake. Animal variations of eating and ruminating rates, but not variations of total eating and ruminating times, were related to those of dry matter intake. Thus, animals which had the highest dry matter intake were those which had the highest eating and ruminating rates.

The variations in digestibility of the same diet (65% maize silage-35% concentrates) in dairy cows during pregnancy and lactation are explained both by dry matter (DM) intake variations (more than 1 pt of decrease in digestibility per kg of increase in DM intake) and physiological stage: digestibility is lower in early lactation than in late pregnancy or mid-lactation.