Shear-stress controlled dynamics of nematic complex fluids

Based on a mesoscopic theory we investigate the non-equilibrium dynamics of a sheared nematic liquid, with the control parameter being the shear stress $\sigma_{\mathrm{xy}}$ (rather than the usual shear rate, $\dot\gamma$). To this end we supplement the equations of motion for the orientational order parameters by an equation for $\dot\gamma$, which then becomes time-dependent. Shearing the system from an isotropic state, the stress- controlled flow properties turn out to be essentially identical to those at fixed $\dot\gamma$. Pronounced differences when the equilibrium state is nematic. Here, shearing at controlled $\dot\gamma$ yields several non-equilibrium transitions between different dynamic states, including chaotic regimes. The corresponding stress-controlled system has only one transition from a regular periodic into a stationary (shear-aligned) state. The position of this transition in the $\sigma_{\mathrm{xy}}$-$\dot\gamma$ plane turns out to be tunable by the delay time entering our control scheme for $\sigma_{\mathrm{xy}}$. Moreover, a sudden change of the control method can {\it stabilize} the chaotic states appearing at fixed $\dot\gamma$.Comment: 10 pages, 11 figure

Some Introductory Remarks

Some introductory remarks to the volume "Troubling Gender. New turbulences in the politics of Gender in Europe".Einige einführende Anmerkungen zum Band "Troubling Gender. New turbulences in the politics of Gender in Europe".Peer Reviewe

Dangerous Convergences of Gender and Race in Migration and Feminist Politics

Right-wing politicians who speak out for women’s rights while attacking emancipatory feminist politics appear to be a contradiction. Nevertheless, studies show that this is a widespread Western phenomenon in fact. It represents a discursive construction, one that Suvi Keskinen understands as a “politics of reversal”: namely as “the adoption and rearticulation of central feminist ideas […] to promote racist agendas” (2018, 161). However, racialized and culturalist gender discourses and images cannot only be found in the context of far-right parties and groups that can be easily and readily defined as “femonationalists” (ibid.). Rather, we can observe “dangerous convergences” of gender and race across the political spectrum, especially in the context of feminist and migration politics. These convergences, how they are produced within feminist as well as migration-related social fields, plus how they circulate and hence structure policies and politics are the focus of this article. We argue that culturalist and racializing gender discourses within current migration and feminist politics reinforce each other—whether intended or not. Hereby several incidences of sections of the international feminist movement deliberately opting for (racial) alliances with the state and law and order policies are illustrated.Rechte Politiker, die sich für die Rechte der Frauen einsetzen und gleichzeitig eine emanzipatorische feministische Politik angreifen, scheinen ein Widerspruch zu sein. Studien zeigen jedoch, dass dies tatsächlich ein weit verbreitetes westliches Phänomen ist. Es stellt eine diskursive Konstruktion dar, die Suvi Keskinen als "Politik der Umkehrung" versteht: nämlich als "die Übernahme und Reartikulation zentraler feministischer Ideen [...], um rassistische Agenden zu fördern" (2018, 161). Rassistische und kulturalistische Geschlechterdiskurse und -bilder sind jedoch nicht nur im Kontext rechtsextremer Parteien und Gruppen zu finden, die sich leicht und einfach als "Femonationalisten" (ebd.) definieren lassen. Vielmehr können wir "gefährliche Konvergenzen" von Geschlecht und Rasse im gesamten politischen Spektrum beobachten, insbesondere im Kontext von feministischer und Migrationspolitik. Diese Konvergenzen, wie sie innerhalb feministischer und migrationsbezogener sozialer Felder produziert werden und wie sie zirkulieren und damit Politiken strukturieren, stehen im Mittelpunkt dieses Beitrags. Wir argumentieren, dass sich kulturalistische und rassifizierende Geschlechterdiskurse in der aktuellen Migrations- und feministischen Politik gegenseitig verstärken - ob beabsichtigt oder nicht. In diesem Zusammenhang werden einige Beispiele aus der internationalen feministischen Bewegung skizzieren, die sich mehr oder weniger bewusst für (rassistische) Allianzen mit dem Staat und der Ordnungspolitik entschieden haben.Peer Reviewe

Memoria y paz. Perspectivas decoloniales en la construcción de la memoria colectiva

The objective of this article is to analyse methodological principles in studies that link the construction of memory with decolonisation. Based on two decolonial approaches, the colonial and epistemic difference, a comparative study of collaborative research on memory in Latin America was carried out. This analysis contributes to the conceptual-critical reflection of the construction of memory in a decolonial framing and presents through innovative methodologies meaning shifts of official narratives. In conclusion, it proposes the integration of the territorial dimension and the subjectivity of the participants and their communities as a way of transformation towards peaceful societie

Transfer of Fibres onto Knife Blades in Stabbing Events: Distribution and Determination of the Stabbing Sequence

Knives are among the weapons most frequently involved in criminal cases. They represent the most encountered category of weapons in Swiss homicide cases (completed and attempted homicides considered) and are also frequently employed in assault cases, notably bodily injuries. Whenever a knife is involved in a stabbing event, DNA and fingerprints may be sought. When garments are damaged, fibres can also be investigated. Fibres from the victim's garments might transfer onto the blade of the knife used in the assault and can thus provide useful information to determine whether a particular weapon could have be used to stab the victim. This study simulates vertical stabbings into garments with the use of a special holding device. Different types of knives and blades straight or serrated were used as weapons. Two garments presenting different shedding capacities and garment structures were also considered for the simulations. The distribution of fibres transferred onto the blade (number and position) was recorded for each simulation performed. Sequences of stabbings into the two garments were also carried out to assess whether the order of the stabs could be determined. Several parameters were considered, notably the distribution of fibres transferred onto the blade. The transfer of fibres inside the stab damage ballistic soap was used in this study and on the area near the second damage was also investigated. This study provides new insight into the interpretation of fibres transferred onto knives after a single stab or a sequence of stabbings and into determining the stabbing sequence. Finally, the study brings some guidelines for the search and recovery of fibres on the crime scene and on the blades of knives