Experimental investigation of the impact, spreading, and drying of picolitre droplets onto substrates with a broad range of wettabilities

NIP27, 27th International Conference on Digital Printing Technologies, Minneapolis, USA, October 2-6, 2011.The effect of the substrate wettability on the deposition of picolitre droplets by drop-on-demand technology is investigated experimentally. Substrates with a broad range of wettabilities are considered with contact angles ranging from 19∘ for water on glass to 118∘ for water on a super-hydrophobic plasma-treated glass slide. Droplet profiles are recorded using high-speed imaging. The effect of surface wettability on the drying of water droplets is investigated and compared with models and experiments from the literature. Results are presented for picolitre droplets and experimental conditions relevant to inkjet printing. The cases of the pinned contact line and the moving one with a constant contact angle are both addressed. For colloidal fluids, the formation of the deposit is further investigated using an inverted microscope coupled to a particletracking velocimetry system. This experimental technique allows us to track individual solute particles during the various stages of the deposition. Preliminary results show the promise of this technique for characterizing internal flows within the droplet

The tame automorphism group in two variables over basic Artinian rings

In a recent paper it has been established that over an Artinian ring R all two-dimensional polynomial automorphisms having Jacobian determinant one are tame if R is a Q-algebra. This is a generalization of the famous Jung-Van der Kulk Theorem, which deals with the case that R is a field (of any characteristic). Here we will show that for tameness over an Artinian ring, the Q-algebra assumption is really needed: we will give, for local Artinian rings with square-zero principal maximal ideal, a complete description of the tame automorphism subgroup. This will lead to an example of a non-tame automorphism, for any characteristic p>0.Comment: 10 page

Private vs. Public Sector : Discrimination against Second-Generation Immigrants in France

The assimilation of immigrants and their children is a burning issue in France. Governments build a large part of their policies on the labor market. The public sector is reputed to integrate minorities better because of its entrance exams and pay-scales. In this paper, a comparison of the public and private sectors shows that second-generation immigrants are not treated equally. Those of African descent are discriminated against in both sectors even though selection issues are controlled for, whereas the wages of those of South European origin are similar to those of the French.Discrimination, wage gap, public and private sectors, France.

Competition and Discrimination : a not so Obvious Relationship

Discrimination models have diffivulties to study discrimination without assuming that prejudiced firms are more productive and results lead to workers' segregation. In this article, the model uses oligopsony and heterogeneity of workers' preferences to obtain a persistent discrimination. Firms hire both thpes of workers and pay a lower wage to the workers discriminated against whatever their taste for discrimination. A single prejudiced firm leads to a substancial wage gap in all firms. Consequently, the existence of discrimination allows a non-zero profit for unprejudiced firms and they have also no incentives to push out prejudiced firms. Moreover, the wage gap is affected by firms' spread out as well as by the number of prejudiced firms in the market. Government policies decrease the impact of taste for discrimination on wages but governments are not interested in.Discrimination, oligopsony, wage gap.

Dear Senator: Young Citizens Explore Civics through Literacy

This article reviews the components of an integration model for infusing literacy and social studies and provides an example of a civics lesson implemented with first grade students. The gradual release model and research-informed literacy practices are embedded in the delivery of instruction. Throughout the learning experience students use informational texts to develop social studies vocabulary, explore civics concepts, and engage in discussion focused on the content in the text. Students acquire skills in supporting their conclusions with information drawn from a variety books and represent the knowledge they have gained through writing activities. This developmental approach harnesses evidence-based strategies that optimize the capabilities of young learners to closely read and deeply reflect upon informational text

Drying and Deposition of Picolitre Droplets of Colloidal Suspensions in Binary Solvent Mixtures

This work was supported by EPSRC grant number RG5560

The nucleotide sequence of a human immnnoglobulin C-gamma-1 gene

We report the nucleotide sequence of a gene encoding the constant region of a human immnnoglobulin γ1 heavy chain (Cγ1). A comparison of this sequence with those of the Cγ2 and Cγ4 genes reveals that these three human Cγ genes share considerable homology in both coding and noncoding regions. The nucleotide sequence differences indicate that these genes diverged from one another approximately 6–8 million years ago. An examination of hinge exons shows that these coding regions have evolved more rapidly than any other areas of the Cγ genes in terms of both base substitution and deletion–insertion events. Coding sequence diversity also is observed in areas of CH domains which border the hinge

Concurrence imparfaite et discrimination sur le marché du travail

International audienceDiscrimination models have difficulties to reproduce a persistent discrimination without assuming that prejudiced firms are more productive and results lead to workers' segregation. The model uses oligopsony and heterogeneity of workers' preferences to obtain a persistent discrimination. Firms hire both types of workers and pay a lower wage to the workers discriminated against. Consequently, the existence of discrimination allows a nonzero profit for unprejudiced firms and they have also no incentives to push out prejudiced firms.Les modèles de discrimination sur le marché du travail reproduisent difficilement sa persistance sans faire d'hypothèses fortes. Cela conduit de surcroît à une ségrégation des travailleurs selon leurs caractéristiques non productives. Dans cet article, le modèle se sert de l'oligopsonie et de l'hétérogénéité des préférences des travailleurs pour obtenir une persistance de la discrimination. Les entreprises embauchent les deux types de travailleurs et offrent un salaire plus faible aux travailleurs discriminés. Par conséquent, l'existence de discrimination sur le marché permet aux entreprises n'ayant pas de goût pour la discrimination de faire des profits non nuls. Elles n'ont donc pas d'incitation à faire sortir les entreprises discriminantes du marché