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Reflectance spectroscopy in the infrared is a powerful tool to characterise the optical properties of analogue materials for Mars. In this work we present laboratory studies of four Martian analogues: calcite, montmordlonite, palagonite and andesite. Diffuse and specular reflectance and transmittance spectra in the IR are shown. The spectral effect produced by small grains clung to the larger ones is analysed for calcite. Significant variations in the diffuse reflectance spectrum, especially in the reststrahlen region, are observed. The diffuse reflectance spectra of the other materials show the shift of the reststrahlen features with Si content in the materials. Optical constants of andesite are retrieved, by using the Lorentz model, from the specular reflectance spectrum. These values are fundamental in performing modelling of the radiance coming from the planet Mars.

In a region of Sudanese savannah in Burkina Faso, insecticide-treated curtains were installed in 8 out of 16 zones, each covering an area of about 50 km 2. Longitudinal entomological monitoring using CDC light traps was performed in 4 villages (2 intervention, 2 control) over a period of 3 years (including 1 year prior to intervention). In the 3rd year a cross-sectional entomological survey using spray catches was performed in 84 villages (40 intervention). Indoor vector densities in protected houses showed large reductions (P= 0·01). The available data were also consistent with an impact on outdoor and unprotected indoor densities. The proportion of mosquitoes carrying sporozoites was 4·1% in protected villages compared with 11·5% in unprotected villages (P= 0·07). Entomological inoculation rates fell substantially (P= 0·01), reflecting these reductions. The impact of this intervention on mosquito survival appears to have been greater than those in similar trials conducted in the Gambia, Ghana and Kenya in which the intervention was applied over smaller areas.

Global sensitivity analysis with the Monte Carlo method is applied to the Boltzmann equation for the electron energy distribution function (eedf). The results show the sensitivity of eedf and related quantities on the global variation of cross sections set. A new indicator of global sensitivity is used, which appears to be of easy applicability.

The exigencies of quickly developing economics and of managing the growth of knowledge and available technologies give the educational task a particular urgency. Such a problem, generally felt in that areas presenting a high technological change rate, is particularly relevant in an always more computerized society, whereas the capability of educating users of social and industrial computer based system means to manage the change. Informatics, so, plays an important role not only as subject of didactical curricula but, over all, in designing and controlling the educational intervention and in realizing the connection between the scientific production and the socio-economic system. Besides evidentiating such problematics, this paper describes some realized products representing the operative tools useful to the implementation of instructional processes in Informatics, in a theoretical context that takes into consideration two models: the learning process model and the educational system one.

Three patients affected by the congenital mono-ophthalmia syndrome were submitted to horizontal eye movements recording. The aim was to study the nystagmus and its characteristics, in order to give information that could explain signs and symptoms of the syndrome.Eye movements recording and analysis displayed a jerk nystagmus with a decreasing-velocity exponential slow phase, characteristic of a latent/manifest-latent nystagmus. The intensity of nystagmus decreased in adduction of the viewing eye, and increased in abduction in accordance with Alexander's law. The fast phase was toward the viewing eye. There was no reversal of the fast phase, nor an instability of gaze in the blind eye.

Measurements of aerosol optical depth are presented in the spectral interval 0.40-1.10 μm, which includes the most transparent region of the solar spectrum and the near infrared. The measurements were obtained by a grating spectrometer with a resolution ≈ 0.5 nm during the 1994 summer season at a mountain site (about 850 m above sea level) in the South of Italy. Spectral regions free from gas absorption features have been singled out and used to retrieve the aerosol columnar size distribution. Inversions have been performed by using the Phillips-Twomey inversion method along with a χ2 criterion which allows one to choose a suitable value for the regularization parameter. The result of the inversions are presented in the particle radius range 0.1 ÷ 3 μm and indicate the presence of a bimodal aerosol with the second mode radius at about 1.0 μm undergoing transformations which are well correlated with relative humidity.

Glassy polymers contain sites where excess free volume makes adsorption of gases possible; they also contain sites where ordinary absorption governed by Henry's law can occur. In this paper, we analyze the possibility of a continuous distribution of site types, characterized by values of adsorption capacity, affinity constant, and sorption constant which span a continuous range. Experimental data are easily fitted with great accuracy by the resulting equations; indeed, different sets of parameter values may fit any given set of data equally well, indicating that evaluation of parameter values from experiments should be regarded with careful skepticism.

Incubating human cells in diethylmaleate (DEM) depletes the intracellular pool of reduced glutathione (GSH) and increases the concentration of oxidative free radicals. We found that DEM-induced oxidative stress reduced the ability of p53 to bind its consensus recognition sequence and to activate transcription of a p53-specific reporter gene. Nevertheless, DEM treatment induced expression of WAF1/CIP1 but not GADD45 mRNA. The fact that N-acetylcysteine, a precursor of GSH that blocks oxidative stress, prevented WAF1/CIP1 induction by DEM suggests that WAF1/CIP1 induction probably was a consequence of the ability of DEM to reduce intracellular GSH levels. DEM induced WAF1/CIP1 expression in Saos-2 and T98G cells, both of which lack functional p53 protein. DEM treatment did not produce an increase in membrane-associated protein kinase C, but ERK2, a mitogen-activated protein kinase, was phosphorylated in a manner consistent with ERK2 activation. DEM treatment also produced a dose-dependent delay in cell cycle progression, which at low concentrations (0.25 mM) consisted of a G2/M arrest and at higher concentrations (1 mM) also involved G1 and S phase delays. Our results indicate that oxidative stress induces WAF1/CIP1 expression and arrests cell cycle progression through a mechanism that is independent of p53. This mechanism may provide for cell cycle checkpoint control under conditions that inactivate p53.

Synthetic peptides have been used to map linear B-cell epitopes of the third variable (V3) region of the feline immunodeficiency virus (FIV) external membrane glycoprotein gp120. The analysis of sera from naturally and experimentally FIV-infected cats by Pepscan and enzyme immunoassay with four partially overlapping peptides evidenced three antibody-binding domains, two of which mapped in the carboxyl-terminal half of V3. In particular, the V3.3 sequence (Gly-392-Phe-413) turned out to be important for in vitro neutralization of the virus in that the peptide inhibited the FIV-neutralizing activity of pooled immune cat sera, and on the other hand, cat sera raised against this peptide effectively neutralized FIV infectivity for Crandell feline kidney cells.

We compared the effectiveness of 2 approaches to assessing child deaths in a rural area of Burkina Faso, West Africa. Censuses, repeated yearly, identified 410 child deaths in the age range 6–59 months. Surveillance using community informants identified only 319 deaths. The estimated sensitivities of the 2 systems were 97% and 76%, respectively. Both systems appeared less effective at detecting child deaths before 6 months of age (sensitivities 74% and 57%). Most of the deaths missed by the census were of children born since the previous census. The cost of one year's surveillance was twice that of a single census. The marginal cost of the surveillance system per additional child death identified between 6 and 59 months was about US$ 1500. Thorough annual censuses may be sufficient to ascertain almost all child deaths over 6 months of age. In studies wishing to identify child deaths before 6 months of age, such an approach is unlikely to be adequate. In such situations, our data indicated that the use of unpaid community informants can improve assessment of deaths. Where accurate assessment of early infant death rate is required, regular visits to each household by members of the study team are likely to be the only reliable approach.

We have investigated the effect of redox changes in vivo on the differentiation of two human myeloid cell lines, HL-60 and KG-1. The glutathione-depleting agent diethyl maleate (DEM) prevented the development of differentiated features in response to phorbol esters, including adherence of the cells to plastic surfaces and repression of the myeloperoxidase and CD34 genes. Moreover, DEM abolished phorbol 12-myristate 13-acetate-induced activation of the transcription factors AP-1 and Egr-1, suggesting that inhibition of differentiation may be due, at least in part, to redox modifications of these proteins.

The dependence of Ångstrom's turbidity parameters on the wavelength has been analyzed in the wavelength interval 0.45-0.70 μm. Measurements of aerosol optical thicknesses in this range were obtained by a wide-range grating spectrometer with a resolution of ∼ 2.5 nm. Based on such measurements, two different methods for obtaining turbidity parameters have been validated and intercompared: (a) the ratio method based on processing couples of aerosol optical depths, and (b) a linear best-fitting method based on log-log plot of aerosol optical thicknesses vs. wavelength. We found that Angstr̊m's turbidity relation is quite effective in characterizing atmospheric aerosol in low-medium turbidity cases. However, the usual method of computing the turbidity parameters on the basis of a few measurements (< 10) does not produce adequate results. Accurate estimates can be only obtained using a larger number of data points

We isolated the gene encoding the brain specific snRNPassociated polypeptide "N" from a rat genomic library. Some intronless genes have previously been reported for this polypeptide in the rat. In contrast, our gene consists of at least nine exons (the last exon(s) encoding the 3′-end of the mRNA has not been isolated). The second intron of the gene is probably so long as to hamper the cloning of the complete gene into a single phage vector. Therefore, we used polymerase chain reaction amplification of the rat genome with oligonucleotides designed on the basis of known cDNA sequences that allowed us to isolate and clone the first two exons at the 5′-end of the gene. Primer extension studies revealed multiple transcription start sites, all of them contained within the first exon. The intron/exon organization coincides with the alternative splicing events suggested by the sequences of the various cDNA species isolated so far. As also reported by others, genomic Southern analysis suggests the presence of other genomic regions containing sequences strongly hybridizing to the cDNA. We isolated and characterized two of these regions. They contain sequences very similar to the cDNA, not interrupted by introns and flanked by a polyA tail at their 3′-ends; hence they are considered two different pseudogenes.

The 190-kilodalton glycoprotein (gp190) of Plasmodium falciparum, the precursor of the major surface proteins of merozoites, is considered a promising candidate for a blood stage malaria vaccine. DNA sequences specific for the gp190 of the two isolates K1 and MAD20 were subcloned and expressed in Escherichia coli. The panel of fusion proteins obtained represents about 80% of the polymorphic sequences observed so far within various isolates of P. falciparum. Sera from individuals living in a malaria-endemic area of West Africa were tested in immunoblots against the gp190 fusion proteins, and antibody reactivity was mapped to defined regions of the gp190. Depending on the age of the individual and on the presence of parasites in the blood, distinct regions of gp190 were differentially recognized by the respective antibodies. Similarly, the analysis of sera from German patients with acute malaria revealed a distinct pattern. When grouped according to age and to parasitemia, the reactivity of the sera of people living in malaria-endemic areas may indicate a correlation between certain gp190 regions and protective immune response.

The DNA sequence specificity for 4,5′,8-trimethylpsoralen cross-linking of DNA has been examined using chemically synthesized DNA fragments containing all possible pyrimidine and purine base pair combinations. We confirm our previous findings that the 5′-TA dinucleotide represents a preferred cross-link site. Other dinucleotides that form cross-links are 5′-AT much greater than 5′-TG greater than 5′-GT. Although 5′-TA represents a preferred cross-link site, the rate of cross-linking can vary 3-4-fold depending on the base composition flanking the cross-linkable 5′-TA dinucleotide. In some cases, changes in DNA sequence 3 base pairs (bp) away from 5′-TA resulted in significant changes in the rate of cross-linking. We also see evidence for a long-range sequence context effect on the rate of cross-linking. A 30-bp fragment cross-linked at a relative rate of 2.9 compared to the rate of cross-linking of a 20-bp fragment when cloned contiguously in plasmid DNA. When cross-linked as separate fragments, the 30-bp fragment cross-linked at a relative rate of 1.9 compared to the 20-bp fragment. The results suggest that the reactivity of DNA to psoralens, and perhaps other intercalating drugs, is dependent on the dinucleotide sequence, the bases flanking the dinucleotide, and the long-range sequence context of the DNA.

Numerical transfer-matrix approach and exact diagonalization technique exploiting the point-group symmetry and the properties of the shift operator are worked out in the framework of quantum statistical mechanics for the isotropic Heisenberg spin Hamiltonian with the ring geometry. They are applied in large-scale simulations to the title high nuclearity cyclic clusters Mn₆ (i.e. [Mn(hfac)₂NITPh]₆) and Ni₁₂ (i.e. Ni₁₂(O₂CMe)₁₂(chp)₁₂(H₂O)₆(THF)₆) in order to model quantitatively their magnetic properties. For Ni₁₂ complex new experimental susceptibility data are also reported. New microscopic spin model parameters for both molecules are obtained from a fit of the theoretical susceptibility curves to the experimental results.

To evaluate whether insecticide‐treated netting (ITN) reduces child mortality in different epidemiological settings, 4 large, randomized, controlled trials were conducted in Africa. Here we report the findings from the trial in Burkina Faso, in an area of hyperendemic and markedly seasonal malaria transmission. The trial involved 158 villages, with a total population of some 90,000, grouped into 16 geographical clusters. Ascertainment of mortality among children aged 6–59 months began in early 1993. In June/July 1994, 8 of the clusters, randomly selected, received permethrin‐treated curtains. Follow‐up of children and ascertainment of mortality continued until May 1996. A 15% reduction in all‐cause mortality among children aged 6–59 months was observed over the 2‐year period following the installation of the curtains (95% c.i. ‐ 4% to 30%). In the first year, post‐intervention mortality was substantially lower in the clusters receiving curtains compared with the control clusters (rate ratio = 0.74; 95% c.i. 0.57, 0.95) but in the second year, there was no difference between mortality in the two groups (rate ratio = 0.99). The overall two‐year impact of the intervention is consistent with the impacts observed in other trials which have demonstrated reductions in child mortality of from 17% to 33%. However, the year‐by‐year analysis raises some concerns about the long‐term effect of ITN. Further follow‐up of this population is warranted.

Wind‐formed features are abundant in Oxia Planum (Mars), the landing site of the 2022 ExoMars mission, which shows geological evidence for a past wet environment. Studies of aeolian bedforms at the landing site were focused on assessing the risk for rover trafficability, however their potential in recording climatic fluctuations has not been explored. Here we show that the landing site experienced multiple climatic changes in the Amazonian, which are recorded by an intriguing set of ridges that we interpret as Periodic Bedrock Ridges (PBRs). Clues for a PBR origin result from ridge regularity, defect terminations, and the presence of preserved megaripples detaching from the PBRs. PBR orientation differs from superimposed transverse aeolian ridges pointing toward a major change in wind regime. Our results provide constrains on PBR formation mechanisms and offer indications on paleo winds that will be crucial for understanding the landing site geology. Oxia Planum on Mars is the landing site for the ExoMars 2022 mission. The region likely hosted a standing body of water, but the effect of the wind was also important in shaping the landscape. In this study, we first describe a set of linear ridges that, in our interpretation, were sculpted by the wind in a more recent past. We also show that the wind that formed the ridges (Periodic Bedrock Ridges) was blowing from a different direction than the ones that formed younger ripples on top, suggesting a complex geological history of wind erosion and deposition that will be further investigated during the ExoMars mission. We present the first evidence for a periodic bedrock ridge (PBRs) pattern from the ExoMars 2022 landing siteFormative paleowind directions are extrapolated from PBRs and transverse aeolian ridgesEvidence for an Amazonian change in the wind regime are provided We present the first evidence for a periodic bedrock ridge (PBRs) pattern from the ExoMars 2022 landing site Formative paleowind directions are extrapolated from PBRs and transverse aeolian ridges Evidence for an Amazonian change in the wind regime are provided

Aeolian megaripples, with 5‐ to 50‐m spacing, are abundant on the surface of Mars. These features were repeatedly targeted by high‐resolution orbital images, but they have never been observed to move. Thus, aeolian megaripples (especially the bright‐toned ones often referred as Transverse Aeolian Ridges—TARs) have been interpreted as relict features of a past climate. In this report, we show evidence for the migration of bright‐toned megaripples spaced 1 to 35 m (5 m on average) in two equatorial areas on Mars indicating that megaripples and small TARs can be active today. The moving megaripples display sand fluxes that are 2 orders of magnitudes lower than the surrounding dunes on average and, unlike similar bedforms on Earth, can migrate obliquely and longitudinally. In addition, the active megaripples in the two study areas of Syrtis Major and Mawrth Vallis show very similar flux distributions, echoing the similarities between dune crest fluxes in the two study areas and suggesting the existence of a relationship between dune and megaripple fluxes that can be explored elsewhere. Active megaripples, together with high‐sand flux dunes, represent a key indicator of strong winds at the surface of Mars. A past climate with a denser atmosphere is not necessary to explain their accumulation and migration. Similar to what is found in deserts on Earth, the wind has accumulated sandy landforms (bedforms) on the Martian surface, such as dunes and ripples. Ripples on Earth are mostly spaced at ~10 cm, but a particular kind of ripples called “megaripples” can be 30 cm to tens of meters spaced. Megaripples have coarse sand grains (>1 mm) accumulated at their crests, so only strong winds can move them. Mars has a faint atmosphere, and according to computer models, winds able to mobilize coarse sand grains are not predicted to blow at the surface. Thus, Martian megaripples are often considered to be static relics of a past climate where the atmosphere was denser. Here we show the first evidence for the movement of bright megaripples on Mars showing that some of these bedforms can be active today and do not require past climatic states for their origin as has been assumed. Bright‐toned megaripple migration is identified on the surface of Mars for the first timeThese features are similar to Transverse Aeolian Ridges, which had been assumed to be dormant under the current climateMegaripple crest fluxes are, on average, 2 orders of magnitude lower than local dune crest fluxes

The interest towards Mars is nowadays renewed as various satellites, already launched or foreseen for the future, will visit this planet, providing a new wealth of data. In particular, infrared spectroscopic observations need a parallel modelling effort for a proper interpretation of observations. The goal of our modelling is to evaluate the influence of a non negligible fraction of dust particles on intensity and profile of atmospheric Martian spectra. The joint effects of the atmosphere and the surface materials have been also accounted for. For the modelling, a version of the MODTRAN code, expressly modified for application to the Mars environment, has been used. As an example of the materials forming dust dispersed in the atmosphere and on the surface, we have considered andesite. Indices of refraction (nand k) of this material have been derived from laboratory measurements. The obtained results can have an important impact on the interpretation of infrared spectra that instruments such as TES (Thermal Emission Spectrometer), on board the Mars Global Surveyor, and PFS, in the Mars Express mission, will provide.

Three different types of gamones, each representing a different mating type ofEuplotes raikovi, were used to elicit the production of antisera in mice. Each type of antiserum proved to be capable of preventing the gamone activity in correlation with the different specificities of the mating type.

In recent years, ceramic coatings have been widely studied for their potential performance in many scientific and technological fields. Ceramic coatings are also used as a textile-finishing agent to impart several properties such as anti-bacterial, anti-abrasion, flame retardant. In this study, fluoro free water repellent finishings have been developed to assess the features of the silica films on the textile fabrics. The water repellency of the treated samples has been evaluated by different tests such as water contact angle, water uptake and drop test.