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Crocodylomorphs were a diverse clade in the Late Jurassic of Portugal, with six taxa reported to date. Here we describe 126 isolated teeth recovered by screen-washing of sediments from Valmitão (Lourinhã, Portugal, late Kimmeridgian–Tithonian), a vertebrate microfossil assemblage in which at least five distinct crocodylomorph taxa are represented. Ten morphotypes are described and attributed to five clades (Lusitanisuchus, Atoposauridae, Goniopholididae, Bernissartiidae and an undetermined mesoeucrocodylian). Four different ecomorphotypes are here proposed according to ecological niches and feeding behaviours: these correspond to a diet based on arthropods and small vertebrates (Lusitanisuchus and Atoposauridae), a generalist diet (Goniopholididae), a durophagous diet (Bernissartiidae) and a carnivorous diet. Lusitanisuchus mitracostatus material from Guimarota is here redescribed to achieve a better illustration and comparison with the new material. This assemblage shares similar ecomorphotypes with other Mesozoic west-central European localities, where a diversity of crocodylomorphs lived together, avoiding direct ecological competition through niche partitioning. The absence of large marine crocodylomorphs, present in other contemporaneous assemblages, is here interpreted as evidence that the Valmitão assemblage was deposited in a freshwater environment, although sample bias cannot be completely ruled out. These affinities are further supported by the presence of lanceolate and leaf-shaped teeth associated with continental clades.

Emergencies can often directly impact health systems of an affected region or country, especially in resource-constrained areas. Health system recovery following an emergency is a complex and dynamic process. Health system recovery efforts have often been structured around the World Health Organization’s health systems building blocks as demonstrated by the Post-Disaster Needs Assessment. Although this structure is valuable and well known, it can overlook the intricacies of public health systems. We retrospectively examine public health systems recovery, a subset of the larger health system, following the 2010 Haiti earthquake and cholera outbreak, through the lens of the 10 essential public health services. This framework illustrates the comprehensive nature of and helps categorize the activities necessary for a well-functioning public health system and can complement other assessments. Outlining the features of a public health system for recovery in structured manner can also help lay the foundation for sustainable long-term development leading to a more robust and resilient health system.

Background: Obstetrical analgesia remains a matter of controversy because of the fear of neurotoxicity of local anesthetics on demyelinated fibers or their potential relationship with subsequent relapses. Objective: To assess the impact of neuraxial analgesia on the risk of relapse during the first 3 months post-partum, with a focus on women who experienced relapses during pregnancy. Methods: We analyzed data of women followed-up prospectively during their pregnancies and at least 3 months post-partum, collected in the Pregnancy in Multiple Sclerosis (PRIMS) and Prevention of Post-Partum Relapses with Progestin and Estradiol in Multiple Sclerosis (POPARTMUS) studies between 1992–1995 and 2005–2012, respectively. The association of neuraxial analgesia with the occurrence of a post-partum relapse was estimated by logistic regression analysis. Results: A total of 389 women were included, 215 from PRIMS and 174 from POPARTMUS. In total, 156 women (40%) had neuraxial analgesia. Overall, 24% experienced a relapse during pregnancy and 25% in the 3 months post-partum. Women with a pregnancy relapse were more likely to have a post-partum relapse (odds ratio (OR) = 1.83, p = 0.02), independently of the use of neuraxial analgesia. There was no association between neuraxial analgesia and post-partum relapse (OR = 1.08, p = 0.78). Conclusion: Neuraxial analgesia was not associated with an increased risk of post-partum relapses, whatever multiple sclerosis (MS) activity during pregnancy.

Background Food insecurity dramatically increased because of the COVID-19 pandemic; however, little is known about pandemic-related food insecurity in households with dietary restrictions. Objective To examine pre-pandemic rates of and pandemic-related change in food insecurity among households with and without dietary restrictions. Methods A cross-sectional, panel-based survey of 3200 U.S. women was conducted in April 2020. Pre-pandemic food insecurity and early pandemic-related change in food insecurity were assessed using the adapted Hunger Vital Sign. Weighted, multivariate logistic regression was used to model the odds of pre-pandemic food insecurity and the odds of incident or worsening pandemic-related food insecurity among households with and without dietary restrictions. In models predicting pandemic-related outcomes, interaction effects between race/ethnicity and dietary restrictions were examined. Results Before the COVID-19 pandemic, households with self-reported food allergy (adjusted odds ratio [aOR]: 1.5, 95% confidence interval [CI]: 1.2-1.9), celiac disease (aOR: 2.3, 95% CI: 1.4-3.5), or both (aOR: 2.1, 95% CI: 1.2-3.6) were significantly more likely to be food insecure than households without restrictions. Households with dietary restrictions were also significantly more likely to experience incident or worsening food insecurity during the early pandemic (food allergy: aOR: 1.6, 95% CI: 1.3-2.1) (celiac disease: aOR: 2.3, 95% CI: 1.5-3.5) (both: aOR: 2.0, 95% CI: 1.2-3.4). Race/ethnicity was not a significant moderator of the relationship between dietary restrictions and pandemic-related food insecurity. Conclusion Households with dietary restrictions were more likely to experience both pre-pandemic and pandemic-related incident or worsening food insecurity than households without restrictions. Clinical care for patients with dietary restrictions requires attention to food insecurity.

Filamentous fungi have a complex morphology that induces fermentation process development issues, as a consequence of viscosity increase and diffusion limitations. In order to better understand the relationship between viscosity changes and fungus morphology during fermentations of Trichoderma reesei, an accurate image analysis method has been developed to provide quantitative and representative data for morphological analysis. This method consisted of a new algorithm called FACE that allowed sharp images to be created at all positions, segmentation of fungus, and morphological analysis using skeleton and topological approaches. It was applied and validated by characterizing samples of an industrial strain of Trichoderma reesei that had or had not been exposed to an extreme shear stress. This method allowed many morphological characteristics to be identified, among which nine relevant criteria were extracted, regarding the impact of shear stress on the fungus and on the viscosity of the fermentation medium.

Tumorigenesis relies on the ability of cancer cells to obtain necessary nutrients and fulfill increased energy demands associated with rapid proliferation. However, as a result of increased metabolite consumption and poor vascularization, most cancer cells must survive in a nutrient poor and high cellular stress microenvironment. Cancer cells undergo metabolic reprogramming to evade cell death and ensure proliferation; in particular, cancer cells utilize the catabolic process of autophagy. Autophagy creates an intracellular pool of metabolites by sequestering cytosolic macromolecules in double-membrane vesicles targeted for lysosomal degradation. During times of environmental stress and nutrient starvation, autophagy is upregulated through the dynamic interactions between two nutrient sensing proteins, AMP activated protein kinase (AMPK) and mechanistic target of rapamycin (mTOR), in cooperation with Unc-51 like autophagy activating kinase 1 (ULK1). In this way, a lack of metabolic nutrients plays a critical role in inducing autophagy, while the products of autophagy also serve as readily available fuel for the cell. In this chapter, we describe methods to visualize and quantify autophagy using a fluorescent sensor of autophagic membranes. Thus, the impact of specific nutrients on autophagy can be measured using live-cell fluorescent microscopy.

Tumorigenesis relies on the ability of cancer cells to obtain necessary nutrients and fulfill increased energy demands associated with rapid proliferation. However, as a result of increased metabolite consumption and poor vascularization, most cancer cells must survive in a nutrient poor and high cellular stress microenvironment. Cancer cells undergo metabolic reprogramming to evade cell death and ensure proliferation; in particular, cancer cells utilize the catabolic process of autophagy. Autophagy creates an intracellular pool of metabolites by sequestering cytosolic macromolecules in double-membrane vesicles targeted for lysosomal degradation. During times of environmental stress and nutrient starvation, autophagy is upregulated through the dynamic interactions between two nutrient sensing proteins, AMP activated protein kinase (AMPK) and mechanistic target of rapamycin (mTOR), in cooperation with Unc-51 like autophagy activating kinase 1 (ULK1). In this way, a lack of metabolic nutrients plays a critical role in inducing autophagy, while the products of autophagy also serve as readily available fuel for the cell. In this chapter, we describe methods to visualize and quantify autophagy using a fluorescent sensor of autophagic membranes. Thus, the impact of specific nutrients on autophagy can be measured using live-cell fluorescent microscopy.

Successful and sustained efforts have been made to curtail the major cholera epidemic that occurred in Haiti in 2010 with the promotion of hygiene and sanitation measures, training of health personnel and establishment of treatment centers nationwide. Oral cholera vaccine (OCV) was introduced by the Haitian Ministry of Health as a pilot project in urban and rural areas. This paper reports the successful OCV pilot project led by GHESKIO Centers in the urban slums of Port-au-Prince where 52,357 persons received dose 1 and 90.8% received dose 2; estimated coverage of the at-risk community was 75%. This pilot study demonstrated the effort, community mobilization, and organizational capacity necessary to achieve these results in a challenging setting. The OCV intervention paved the way for the recent launching of a national cholera vaccination program integrated in a long-term ambitious and comprehensive plan to address Haiti's critical need in water security and sanitation.

A cholera epidemic has claimed the lives of more than 8,000 Haitians and sickened 650,000 since the outbreak began in October 2010. Early intervention in the epidemic focused on case-finding, treatment, and water and sanitation interventions for prevention of transmission. Use of oral cholera vaccine (OCV) as part of a complementary set of control activities was considered but initially rejected by policymakers. In December 2011, the Minister of Health of Haiti called for a demonstration of the acceptability and feasibility of the use of OCV in urban and rural Haiti. This paper describes the collaborative activity that offered OCV to one region of the Artibonite Department of rural Haiti in addition to other ongoing treatment and control measures. Despite logistics and cold chain challenges, 45,417 persons were successfully vaccinated with OCV in the region, and 90.8% of these persons completed their second dose.

A new deuterium ice pellet injector is in preparation for JET. It is designed to inject both small pellets (variable volume within 1–2 mm 3 ) at high frequency (up to 60 Hz) for ELM mitigation experiments and large pellets (volume within 35–70 mm 3 ) at moderate frequency (up to 15 Hz) for plasma fuelling. It is based on the screw extruder technology developed by PELIN and pneumatic acceleration. An injection line will connect the injector to the flight tubes already in place to convey the pellets toward the plasma either from the low field side or from the high field side of the torus. This injection line enables: (i) the pumping of the propellant gas, (ii) the provision of the vacuum interface with the torus and (iii) the selection of the flight tube to be used via a fast selector. All the interfaces have been designed and a prototype injector is being built, to demonstrate that the required performance is achievable.

For a better understanding of the mechanisms that lead to the preovulatory GnRH/LH surge and estrus behavior, the minimum estradiol (E) requirements (dose and duration) to induce each of these events were determined and compared between two breeds of ewes having either single (Ile de France) or multiple (Romanov) ovulations. The ewes were initially studied during a natural estrus cycle, and were then ovariectomized and run through successive artificial estrus cycles. For these artificial cycles the duration and amplitude of the follucular phase E increase were manipulated by E implants. Under all conditions, the onset of estrus behavior was similar in the two breeds, although its duration was longer in Romanov ewes. While a moderate E signal (6 cm for 12 h) induced an LH surge in 10/10 Ile de France ewes, a larger E signal (12 cm for 12 h) was minimally effective in Romanov ewes (4/10). Additional studies revealed that a small E signal (3 cm for 6 h) induced full estrus behavior in all Romanov ewes but was completely ineffective in Ile de France animals (0/10). Higher doses and mostly longer durations of the E signal (12 cm for 24 h) were required to induce a surge in all the Romanov ewes. These results demonstrate a clear difference in the E requirement for the induction of estrus behavior and the LH surge between breeds of ewes that have different ovulation rates. These data provide compelling evidence that, in one breed, the neuronal systems that regulate both events require different estrogen signals.

International audience; This work is dedicated to the characterization of CoMoP/Al2O3 hydrotreatment catalysts. In order to identify the neighboring of cobalt and molybdenum, X-ray photoelectron spectroscopy (XPS), transmission electron spectroscopy (TEM) and activity measurements were used. Indeed, a quantitative XPS characterization was developed to study the effect of the Co/Mo atomic ratio on CoMoP-type hydrodesulfurization catalysts.Identification and quantification of the various species present on the surface of the catalysts were performed. We showed that the catalyst exhibiting both the maximum activity in hydrogenation of tolueneand the maximum amount of CoMoS active, determined through the XPS quantitative analysis, is the catalyst with a Co/Mo atomic ratio equal to 0.5. However, all the cobalt atoms are not completely engagedin the CoMoS mixed phase.

The first oral cholera vaccine (OCV) campaign, since its prequalification by the World Health Organization, in response to an ongoing cholera epidemic (reactive vaccination) was successfully conducted in a poor urban slum of approximately 70,000 inhabitants in Port-au-Prince, Haiti, in 2012. Vaccine coverage was 75% of the target population. This report documents the impact of OCV in reducing the number of culture-confirmed cases of cholera admitted to the Groupe Haitien d'Etude du Sarcome de Kaposi et des Infections Opportunistes (GHESKIO) cholera treatment center from that community in the 37 months postvaccination (April 2012-April 30, 2015). Of 1,788 patients with culture-confirmed cholera, 1,770 (99%) were either from outside the vaccine area (1,400 cases) or from the vaccinated community who had not received OCV (370 cases). Of the 388 people from the catchment area who developed culture-confirmed cholera, 370 occurred among the 17,643 people who had not been vaccinated (2.1%) and the remaining 18 occurred among the 52,357 people (0.034%) who had been vaccinated (P < 0.001), for an efficacy that approximates 97.5%. Despite not being designed as a randomized control trial, the very high efficacy is a strong evidence for the effectiveness of OCV as part of an integrated package for the control of cholera in outbreak settings.

The effect of the sulfidation temperature on the nature and amount of active phases of CoMoP-type hydrodesulfurization catalysts was investigated. An X-ray photoelectron spectroscopy quantification approach was developed, allowing us to show a direct relation between the amount of mixed CoMoS active phase as determined by XPS and the catalytic activity. XPS, transmission electron microscopy (TEM) and toluene-hydrogenation activity correlations also showed that the sulfidation temperatures should range between 350 and 500 °C. Under these conditions the catalysts are mainly composed of MoS2 and CoMoS active phases and present a maximum of activity. Copyright © 2006 John Wiley & Sons, Ltd.

The appropriate dosage regimen for equine FSH (eFSH) (dose, dosing interval) administration in a superovulation treatment in pony mares was determined by a kinetic approach using production rates and kinetic parameters of elimination of the hormone. Two dosage regimens were then tested in superovulation protocols. The eFSH production rates were determined by sampling four ovariectomized pony mares every 10 min for 8 h during the breeding season. Kinetic parameters were determined by administering four dose levels of a preparation of eFSH (4.4, 8.8, 17.6 and 35.2 micro g/kg) by the i.v. route to the same mares, in a randomized 4x4 Latin Square protocol. The overall mean plasma clearance was 0.256+/- 0.07 ml.kg(-1).min(-1), and was independent of the dose. The mean residence time ranged from 5.5 to 10.8 h and increased with the dose. The estimated FSH production rates were 8.6 to 15.3 micro g.kg(-1).day(-1) (i.e. 2.89 to 3.45 mg per day per mare). Two dosage regimens of eFSH were then tested in cyclic mares (ten treated mares in each trial): 3.45 mg per day (4.4 micro g/kg three times a day by the i.v. route), which corresponds to the maximal daily production rate of the native hormone in ovariectomized mares, and 1.72 mg per day (2.2 micro g/kg three times a day), which corresponds to half of that production rate. The dosage regimen of 2.2 micro g/kg three times a day gave satisfactory results in terms of efficacy (numbers of ovulations and embryos) with minimal unwanted effects (luteinized or anovulatory follicles).

The evolution of textural properties of Na/Ca-bentonite from Wyoming (MX-80) was studied by adsorption of nitrogen, water vapour, and ethylene glycol monoethyl ether. Clay suspensions were heated at 80 and 300ºC for up to 9 months in the absence of or in the presence of Fe and/or Fe oxides. The treatment without Fe did not change the textural properties of the samples significantly. The treatment at 80ºC in the presence of Fe resulted in a considerable increase in the external surface areas of the samples. The total and external surface areas and swelling capacities of the samples decreased following the treatment at 300ºC in the presence of Fe and Fe oxides. In the case of larger additions of Fe, the treatment at 300ºC resulted in a considerable decrease in the total and external surface areas and swelling capacity of the sample and in the formation of a network of large-size pores, in which all the pores were connected.

The GnRH antagonist antarelix (Teverelix™) was administered to mares (0.01mg/kg, i.v., twice a day) during the periovulatory period. In Experiment 1, 20 mares were divided into a treated (A3d−) and a control (Control−) group. A3d− mares received antarelix for 3 days from the day when the dominant follicle (F1) reached 32mm (D0). In Experiment 2, 10 mares were divided into a treated (A6d+) and a control (Control+) group. A6d+ mares received antarelix for 6 days from D0 and hCG was injected in all animals (1600IU, i.v.) on D1. Pregnancies were determined 13 days after ovulation. In both experiments, antarelix interrupted or totally abolished the LH surge. In Experiment 1, 5/10 of the A3d− mares (with maximum LH concentrations of 11.6ng/ml at the beginning of treatment) ovulated at the same time as the Control− mares; the other five mares (with LH concentrations under 5.4ng/ml) ovulated 13.4±0.6 days later. In Experiment 2, all the A6d+ mares ovulated at the same time as the Control+ mares. In treated mares which ovulated during the treatment, progesterone concentrations and fertility did not differ from control mares. These results demonstrate that in mares: (1) a small elevation of endogenous LH can induce ovulation, (2) ovulation can be postponed approximately 13 days after a 3-day antarelix treatment if initiated just before the preovulatory LH surge, (3) ovulation can be induced by hCG on depressed levels of endogenous LH, (4) the inhibition of the post ovulatory LH surge has no effect either on the corpus luteum or on fertility.

Surface platinum of sulfated zirconia has been characterized by hydrogenation of toluene at 150°C and by carbon monoxide adsorption on a series of catalysts containing 0.025–0.8 wt% Pt. The variation of the hydrogenation rate with the Pt content showed two linear domains with a sharp increase at 0.15 wt% Pt. A very good correlation between hydrogenation activity and CO adsorption indicates that the low activity at low loading results from a lack of accessible platinum. We suggest that part of the platinum migrated to the subsurface of the zirconia matrix. After the saturation of the subsurface platinum sites, additional platinum is located on the surface with a constant particle size of about 1 nm. Combination of these results with those of the isomerization of n -hexane at 150°C indicates that very active surface platinum does not play the key role in isomerization. The influence of hydrogen on the isomerization activity nicely correlates with the estimated amount of platinum inserted in the subsurface of zirconia. Reduction of the catalysts at higher temperatures (up to 250°C) diminishes strongly the toluene hydrogenation activity of the samples, while n -hexane isomerization is hardly affected. This is further proof of the importance of subsurface platinum in isomerization and supports the kinetic model based on Lewis acid sites, where desorption of the isocarbenium ion is assisted by hydrides formed on subsurface platinum.

A rapid, sensitive and specific high-performance liquid chromatographic method for the quantification of acrolein (1), one of the toxic metabolites of oxazaphosphorine alkylating agents (cyclophosphamide and ifosfamide) was developed. Condensation of acrolein with Luminarin® 3 afforded a fluorescent derivative that could be specifically detected and quantified. Chromatographic conditions involved a C18 RP column Uptisphere and a gradient elution system to optimize resolution and time analysis. The method showed high sensitivity with a limit of detection of 100 pmol/ml and a limit of quantification of 300 pmol/ml. This technique is particularly suitable for pharmacokinetic studies on plasma of oxazaphosphorine-receiving patients.

In this paper, we have studied the effect of chlorine on the surface properties of gamma-alumina, especially on their acid properties. The use of FTIR spectroscopy and 31P MAS NMR of adsorbed trimethylphosphine allows to propose a chlorination mechanism. To correlate the surface properties of these chlorinated gamma-alumina with their catalytic properties, we have used a model reaction, the cracking of n-heptane under reforming conditions. The analysis of the correlation between acid properties determined by 31P MAS NMR and the catalytic results (in terms of activities and selectivities) allows to identify which sites are involved in the cracking reaction.

Transport of ions and molecules was studied in hydrogels of uncharged and anionic biopolymers, agarose and iota-carrageenan. Diffusion coefficients of neutral and ionic electroactive probes, the uncharged radical 2,2,6,6-tetramethyl-1-pipperidinyloxy, TEMPO, and Tl(I), were determined rapidly and precisely from steady-state transport-limited currents at platinum and mercury microelectrodes. Transport properties of both probes were studied in gels as effected by temperature, ionic strength and concentration of the biopolymer, and they were compared with those in solutions. The relation between macroscopic and local microscopic viscosity of biopolymeric gels was analyzed based on viscosity measurements and diffusion coefficient data.

Ghrelin-28 was found to inhibit the pancreatic enzyme output in rats, although the effect of pentaghrelin has not been studied. The effect of ghrelin on pig exocrine pancreas remains largely unknown. The aim of the present study was: (1) to establish a model of porcine dispersed pancreatic acinar cells in vitro and compare it with an existing rat model, and (2) to investigate the effect of pentaghrelin on amylase release from the rat and pig pancreatic acini. The rat and porcine acinar cell preparations released amylase in response to cholecystokinin octapeptide (CCK-8) stimulation in a dose-related manner. Pentaghrelin hardly inhibited the amylase release in rat preparations (maximum inhibition with 10− 9 M pentaghrelin). It stimulated amylase release in porcine preparations, however, no dose response was found in a range of doses between 10− 10 and 10− 7 M. Concluding, pentaghrelin may stimulate amylase release from porcine acinar cells through as yet unknown mechanisms.

The motion planning solution of a simplified car presented in (Fliese et ai, 1995) admits a geometric formulation through the Frenet formulae. We present and use this formulation that preserves the invariance with respect to SE (2) to built a global asymptotic observer of the non measured direction of the car via the only measurement of its position. Then we study the tracking of a planned path with an observer-controller. Although, the observer-controller stability proof is only local, the attraction domain seems to be very large as shown by numeric simulations (Matlab scripts are available from the authors via email).

A smooth observable system, ẋ = f(x), y = h(x) , that can be put, after a change of state coordonates x ↦ X , into X = A(y)X + b(y) with an implicit observation equatIon C(y)X = d(y) , is said to be transformable into an implicit affine form. Characterization of such systems is an open problem. For single output systems, a necessary const.ructive condition on the structure of the differential Equation satisfied by the output is given. When dim(x) = 2 , this necessary condition, ӱ - f o (y) + f 1 (y)ẏ + f 2 (Y)ẏ 2 + f 3 (y)ẏ 3 , is shown to be sufficient.

Countries around the world face a perfect storm of converging threats that might substantially increase the risk from infectious disease epidemics, despite improvements in technologies, communication, and some health systems.

31P MAS NMR of adsorbed trimethylphosphine (TMP) has been used to characterize the surface acid properties of γ-alumina and chlorinated γ-alumina. Combined with thermodesorption of TMP, NMR has allowed the determination of the strength distribution of Bronsted and Lewis acid sites on these samples. γ-alumina chlorination with 1,2-dichloropropane at 500°C first increases the numbers of ``strong'' Lewis and ``strong'' Bronsted acid sites, second decreases the number of ``weak'' Lewis acid sites. The ``strong'' sites are the ones TMP is desorbed from above 200°C and the ``weak'' sites up to 200°C.

International audience; We report on the production of a windowless pure hydrogen H2 film. The thickness is within therange 50–200 μm, in order to be used as a target for nuclear reactions in inverse kinematics with radioactivebeams at low incident energy (2–15MeV/nucleon). We give details about the production conditions and afirst in-beam test in order to measure the thickness and the homogeneity with a 3MeV proton beam.

We extend the method due originally to Loh and Niebuhr for the generation of Carmichael numbers with a large number of prime factors to other classes of pseudoprimes, such as Williams's pseudoprimes and elliptic pseudoprimes. We exhibit also some new Dickson pseudoprimes as well as superstrong Dickson pseudoprimes.

CEA-Leti has developed a real-time reflection imaging system: it combines illumination by QCL sources and a telescope that focuses the reflected radiation onto a camera that houses an uncooled 320×240 antenna-coupled micro-bolometer array driven by a FPGA card. We present first high resolution images of illuminated surfaces acquired in real-time.

Classical photostimulation of winter anoestrous mares consists of a light treatment with 14.5-16.0 h white light (100 lux), starting near the time of the winter solstice and ending around the time of the summer solstice. Cyclicity is obtained typically after about 70 days of treatment. The aim of the present study was to establish the minimum number of days of treatment, the lowest light intensity and the duration of light required per day to advance the onset of ovarian activity in winter anoestrous mares. In Expt 1 it was demonstrated that a 35 day exposure to a photoperiod (14.5 h light: 9.5 h dark, 100 lux) starting at about the winter solstice is sufficient to advance the onset of the breeding season of Pony mares undergoing winter anoestrus. In Expt 2 it was established that a light of only 3 lux intensity inhibits an increase in melatonin concentrations in the evening after the usual time of switching the lights off. In Expt 3, a low light intensity (10 lux) produced with a 25 W white incandescent bulb was sufficient for photostimulation of the mares. In Expts 4 and 5, 1 h light (10 lux) during the photosensitive phase for 35 days advanced the onset of the breeding season in only half of the mares treated.

The relationship between thyroid function and seasonal reproductive activity in mares was investigated by comparing plasma triiodothyronine and thyroxine concentrations in anoestrous mares and in mares with cyclic ovarian activity during the anovulatory season. In study 1, the diurnal changes in plasma triiodothyronine and thyroxine concentrations on a single day were compared in anoestrous and cyclic mares. The mean thyroxine concentrations were significantly higher (P0.001) in the cyclic mares than in the anoestrous mares, whereas mean triiodothyronine concentrations were similar in both groups. In study 2, plasma thyroid hormone concentrations were monitored in mares that foaled before the vernal equinox. Nine mares resumed cyclic ovarian activity shortly after parturition and ten mares remained in anoestrus. Mean plasma triiodothyronine and thyroxine concentrations were significantly lower in the first 60-90 days after foaling in the mares undergoing anoestrus than in the mares undergoing normal ovarian activity after parturition (P0.001). In these mares, the increases in triiodothyronine and thyroxine concentrations were associated with the first ovulation after parturition. In study 3, thyroid hormone concentrations were monitored in adult (n=14) and young (n=14) mares. Mean thyroxine concentrations were significantly lower in adult anoestrous mares during the anovulatory period than in cyclic mares and in anoestrous mares before and after the anovulatory period (P0.01). Mean plasma triiodothyronine concentrations were also significantly lower (P0.001) in anoestrous mares from December until March. There were no significant differences between the plasma triiodothyronine and thyroxine concentrations in young cyclic and anoestrous mares. This relationship between thyroid function and expression of seasonal reproductive activity does not indicate that the thyroid gland is involved in the control of seasonality in horses. The decreased triiodothyronine and thyroxine concentrations in anoestrous mares may be the result of a hypothalamic control similar to that described for seasonal reproductive activity.

Brain maturation and GABA metabolism are known to play a key role in epileptogenesis. The metabolism of the polyamines (putrescine, spermidine and spermine) is closely linked to the process of brain maturation. Putrescine has been shown to be catabolized to GABA in brain tissue and astrocytes. In order to better understand the importance of glial putrescine transport and metabolism, a model of age-dependent epilepsy was used to study the kinetic properties of [14C]putrescine uptake into cultured astrocytes from normal C57/BL and audiogenic DBA/2 newborn mice, and the subsequent GABA formation. (1) Putrescine uptake exhibited non-Michaelian allosteric kinetics with positive co-operativity (Hill factor = 2), suggesting a physiological importance of putrescine uptake by astrocytes. (2) The Vmax of putrescine uptake was significantly higher in C57/BL astrocytes than in DBA/2J, but the uptake affinity for putrescine was higher in DBA/2J than in C57/BL. (3) High K+ concentrations (18 mM) had little effect on putrescine uptake in either strain. (4) Ten-micromolar N-acetylputrescine, the first putrescine metabolite, stimulated putrescine uptake into astrocytes of both strains, but to a different degree: +46% in C57/BL and +102% in DBA/2J. (5) The specific radioactivity of the GABA formed from labelled putrescine was four times higher in astrocytes from DBA/2J than from C57/BL mice. (6) The molar ratio of glutamate/GABA in the cerebral cortex of the DBA/2J mice was significantly higher during the period of audiogenic seizure susceptibility than in age-matched C57/BL mice. Our results show characteristics of putrescine uptake into astrocytes; we demonstrated distinct kinetic properties between normal and epileptic strains of mice. Moreover, astrocytic polyamine contents and putrescine catabolism into GABA were increased for the audiogenic mice.

International audience; In order to understand asphaltene reactivity under hydrotreatment conditions,a new strategy is proposed. A cross-flow membrane ultrafiltration method is applied in order to control asphaltene aggregate size polydispersity. At the same time, a feedstock reconstitution method that allowsasphaltene dispersion in maltenes is established. Catalytic tests are carried out, showing that thedeveloped feedstock reconstitution method allows one to preserve asphaltenes' natural reactivity underhydrotreatment conditions. In further studies, the developed methodology will allow the study of the effectof asphaltene aggregate size on hydrotreatment activities by the reconstitution of feedstocks containingcontrolled aggregate size.

SUMMARY: The activity of carbonic anhydrase (CA), a glial enzyme, was measured in the epileptic cortex of audiogenic DBA/2 mice and of cats with a freeze lesion. In mice, the activity increased with age from birth to 24 days, but were always higher in audiogenic mice than in normal C57/BL mice, reflecting species differences. The difference between the two strains increased sharply from 25 to 40 days of age, after the period of maximal audiogenic susceptibility. Acetazolamide, a CA-specific inhibitor, greatly decreased the seizure severity score of DBA/ 2 mice after a single intraperitoneal (i.p.) administration (150 mg/kg). After 24 days of age, when CA activities were high, the effect of acetazolamide was less important, suggesting that the increased cortical CA activity might reflect a protective mechanism. In cats with a freeze lesion, no significant changes in CA activities were observed in the actively discharging primary and secondary foci as compared with the nonepileptogenic perifocal cortex and the control cortex of sham-operated animals. The results indicate that the cortex of genetically susceptible audiogenic mice has an increased CA activity. The hypothesis of an adaptive glial mechanism, relating to the age-dependent decrease of seizure susceptibility in DBA/2 mice, is postulated. RESUME L'activite de I'anhydrase carbonique (AC), une enzyme gliale, a ete mesuree dans des homogenats de cortex epileptique chez la souris audiogene DBA/2 et chez le chat porteur d'une lesion par le froid. Chez la souris, l'activite enzymatique augmente avec l'âge depuis la naissance jusqu'a 24 jours, mais est toujours superieure chez la souris audiogene par rapport a la souche controle C57/BL, refletant des differences genetiques. Entre 25 et 40 jours de vie postnatale, c'est a dire apres la periode de susceptibilite audiogenique maximale, la difference entre les deux souches s'accroit fortement. L'aceHazolamide, un inhibiteur specifique de l'AC, diminue de facon importante le score de severiteepileptique de la souris DBA/2 apres une administration intrapeitoneale unique (150 mg/kg). Cet effet de l'acetazolamide est moins marque lorsque l'activite AC est elevee, suggerant que l'augmentation de l'activite de l'AC apres 24 jours chez la souris DBA/2 pourrait constituer un meanisme protecteur. Chez le chat porteur d'une leion par le froid, aucune modification significative de l'activite enzymatique n'est observee dans les foyers epileptiques actifs primaires et secondares par rapport au cortex perifocal non epileptique et au cortex controle de chats temoins. Ces resultats indiquent l'existence d'une augmentation de l'activite de l'AC dans le cortex de souris genetiquement audiogeniques. L'hypothese d'un mecanisme glial adaptatif, en relation avec la disparition de la susceptibilite audiogenique avec l'âge chez la souris DBA/2, est evoquee. RESUMEN Se ha medido la actividad de la carbonico-anhidrasa (CA), una enzima glial, en la corteza epileptica de los ratones audiogenicos DBA/2 y en gatos con lesiones por congelacion. En las ratas la actividad se incrementa con la edad desde el nacimiento hasta los 24 dias pero fue siempre mas elevada en ratones audiogenicos que en ratones normales C57/BL, lo que refleja diferencias de especie. Las diferencias entre los dos tipos de raton se incrementaron abruptamente desde los 25 a los 40 dias de edad despues de un periodo de susceptibilidad audiogenica maxima. La acetazolamida, un inhibidor especifico de la CA, incremento la severidad de la frecuencia de ataques de los ratones DBA/2 despues de una inyeccion intraperitoneal unica (150 mg/kg). Despues del dia 24 de edad, cuando la actividad de la CA era elevada, el efecto de la acetazolamida fue menos importante, lo que sugiere que el incremento de la actividad cortical de la CA puede reflejar un mecanismo de proteccion. En gatos con lesiones por congelacion no se observaron cambios significativos en la actividad de la CA cuando se buscaron en la zona activamente primaria de descargas y en los focos secundarios, comparandolos con la corteza periofocal no-epileptogenica y con los animales control con tecnica operatoria similar (Sham). Los resultados indican que la corteza de ratones geneticamente susceptibles a crisis audiogenicas tiene un incremento de la actividad de la CA. Los autores postulan la existencia de un mecanismo adaptativo glial, en relation con una reduccion de la susceptibilidad para ataques edad-dependientes, en los ratones DBA/2. ZUSAMMENFASSUNG Die Aktivitat von Carboanhydrase (CA), einem glialen Enzym, wurde im epileptischen Kortex von audiogenen DBA/2-Mausen und Katzen mit Gefrierlasionen gemessen. Bei Mausen stieg die Aktivitat mit dem Alter von Geburt bis zum 24. Tag an, sie war bei audiogenen Mausen immer hohen als bei normalen C57/BL-Mausen. Der Unterschied zwischen den beiden Stammen stieg stark vom 25. zum 40. Lebenstag an, also nach der Periode der maximalen audiogenen Empfindlichkeit. Acetazolamid, ein spezifischer CA-Hemmer, minderte nach einer einzigen intraperitonealen Gabe (150 mg/kg) stark den Schweregrad-Rang von Anfallen von DBA/2-Mausen. Nach dem 24. Lebenstag, wenn die CA-Aktivitaten hoch waren, war die Wirkung von Acetazolamid weniger deutlich, was nahelegt, das die erhohte kortikale CA-Aktivitat einen protektiven Mechanismus wiedergibt. Bei Katzen mit Gefrierlasionen waren keine signifikanten CA-Aktivitatsanderungen bei aktiv entladenden primaren und sekundaren Foci zu sehen im Vergleich zum nichtepileptogenen perifokalen Kortex und zu scheinoperierten Kontrolltieren. Die Ergebnisse zeigen, das der Kortex von genetisch-audiogenen Mausen eine erhohte CA-Aktivitat hat. Es wird die Hypothese aufgestellt von einem adaptiven glialen Mechanismus, der alterabhangig zu einem Abfall der Anfallsempfindlichkeit bei DBA/2-Mausen fuhrt.