Activity-Regulated microRNAs: Modulators of Synaptic Growth at the Drosophila Neuromuscular Junction

It is well established that long-term changes in synaptic structure and function are mediated by rapid activity-dependent gene transcription and new protein synthesis. A growing body of evidence supports the involvement of the microRNA (miRNA) pathway in these processes. We have used the Drosophila neuromuscular junction (NMJ) as a model synapse to characterize activity-regulated miRNAs and their important mRNA targets. Here, we have identified five neuronal miRNAs (miRs-1, -8, -289, -314, and -958) that are significantly downregulated in response to neuronal activity. Furthermore we have discovered that neuronal misexpression of three of these miRNAs (miR-8, -289, and -958) is capable of suppressing new synaptic growth in response to activity suggesting that these miRNAs control the translation of biologically relevant target mRNAs. Putative targets of the activity-regulated miRNAs-8 and -289 are significantly enriched in clusters mapping to functional processes including axon development, pathfinding, and axon growth. We demonstrate that activity-regulated miR-8 regulates the 3'UTR of wingless, a presynaptic regulatory protein involved in the process of activity-dependent axon terminal growth. Additionally, we show that the 3'UTR of the protein tyrosine phosophatase leukocyte antengen related (lar), a protein required for axon guidance and synaptic growth, is regulated by activity-regulated miRNAs-8, -289, and -958 in vitro. Both wg and lar were identified as relevant putative targets for co-regulation based through our functional cluster analysis. One putative target of miR-289 is the Ca2+/calmodulin-dependent protein kinase II (CamKII). While CamKII is not predicted as a target for co-regulation by multiple activity-regulated miRNAs we identified it as an especially pertinent target for analysis in our system for two reasons. First, CamKII has an extremely well characterized role in postsynaptic plasticity, but its presynaptic role is less well characterized and bears further analysis. Second, local translation of CamKII mRNA is regulated in part by the miRNA pathway in an activity-dependent manner in dendrites. We find that the CamKII 3'UTR is regulated by miR-289 in-vitro and this regulation is alleviated by mutating the `seed region' of the miR-289 binding site within the CamKII 3'UTR. Furthermore, we demonstrate a requirement for local translation of CamKII in motoneurons in the process of activity-regulated axon terminal growth.

Restrictive and Expansive Views of Equality: A Grounded Theory Study that Explores the Influence of Racial Consciousness on the Behaviors of White Faculty in the Classroom

Attempts to address the ever increasing achievement gap among students have failed to explain how and why educational traditions and teaching practices perpetuate the devaluing of some and the overvaluing of others. This predicament, which plagues our educational system, has been of increased concern, given the growing racial diversity among college students and the saturation of White faculty in the academy. White faculty make up the majority, 79%, of all faculty in the academy. White faculty, whether consciously or unconsciously, are less likely to interrogate how race and racism both privilege them within the academy and influence their faculty behaviors. The result of this cyclical, highly cemented process suggests that there is a relationship between racial consciousness and White faculty members' ability to employ behaviors in their classroom that promote equitable educational outcomes for racially minoritized students. An investigation of the literature revealed that racial consciousness and the behaviors of White faculty in the classroom appeared to be inextricably linked. A conceptual framework, Racial Consciousness and Its Influence on the Behaviors of White Faculty in the Classroom was developed by the author and tested in this study. Constructivist grounded theory was used to explore the role White faculty believe they play in the dismantling of the white supremacy embedded in their classrooms through their faculty behaviors. A substantive theory subsequently emerged. Findings indicate that White faculty with a higher level of racial consciousness employ behaviors in their classroom reflective of a more expansive view of equality in their pursuit of social justice, which they consider synonymous with excellence in teaching. This research bears great significance to higher education research and practice, as it is the first of its kind to utilize critical legal scholar Kimberlé Crenshaw's (1988) restrictive and expansive views of equality framework to empirically measure and describe excellence in college teaching. Implications for faculty preparation and continued education are also discussed.

Spectral features in isolated neutron stars induced by inhomogeneous surface temperatures

The thermal X-ray spectra of several isolated neutron stars display deviations from a pure blackbody. The accurate physical interpretation of these spectral features bears profound implications for our understanding of the atmospheric composition, magnetic field strength and topology, and equation of state of dense matter. With specific details varying from source to source, common explanations for the features have ranged from atomic transitions in the magnetized atmospheres or condensed surface, to cyclotron lines generated in a hot ionized layer near the surface. Here, we quantitatively evaluate the X-ray spectral distortions induced by inhomogeneous temperature distributions of the neutron star surface. To this aim, we explore several surface temperature distributions, we simulate their corresponding general relativistic X-ray spectra (assuming an isotropic, blackbody emission), and fit the latter with a single blackbody model. We find that, in some cases, the presence of a spurious ‘spectral line’ is required at a high significance level in order to obtain statistically acceptable fits, with central energy and equivalent width similar to the values typically observed. We also perform a fit to a specific object, RX J0806.4−4123, finding several surface temperature distributions able to model the observed spectrum. The explored effect is unlikely to work in all sources with detected lines, but in some cases it can indeed be responsible for the appearance of such lines. Our results enforce the idea that surface temperature anisotropy can be an important factor that should be considered and explored also in combination with more sophisticated emission models like atmospheres.

Muscle-Type Nicotinic Receptor Blockade by Diethylamine, the Hydrophilic Moiety of Lidocaine

Lidocaine bears in its structure both an aromatic ring and a terminal amine, which can be protonated at physiological pH, linked by an amide group. Since lidocaine causes multiple inhibitory actions on nicotinic acetylcholine receptors (nAChRs), this work was aimed to determine the inhibitory effects of diethylamine (DEA), a small molecule resembling the hydrophilic moiety of lidocaine, on Torpedo marmorata nAChRs microtransplanted to Xenopus oocytes. Similarly to lidocaine, DEA reversibly blocked acetylcholine-elicited currents (IACh) in a dose-dependent manner (IC50 close to 70 μM), but unlike lidocaine, DEA did not affect IACh desensitization. IACh inhibition by DEA was more pronounced at negative potentials, suggesting an open-channel blockade of nAChRs, although roughly 30% inhibition persisted at positive potentials, indicating additional binding sites outside the pore. DEA block of nAChRs in the resting state (closed channel) was confirmed by the enhanced IACh inhibition when pre-applying DEA before its co-application with ACh, as compared with solely DEA and ACh co-application. Virtual docking assays provide a plausible explanation to the experimental observations in terms of the involvement of different sets of drug binding sites. So, at the nAChR transmembrane (TM) domain, DEA and lidocaine shared binding sites within the channel pore, giving support to their open-channel blockade; besides, lidocaine, but not DEA, interacted with residues at cavities among the M1, M2, M3, and M4 segments of each subunit and also at intersubunit crevices. At the extracellular (EC) domain, DEA and lidocaine binding sites were broadly distributed, which aids to explain the closed channel blockade observed. Interestingly, some DEA clusters were located at the α-γ interphase of the EC domain, in a cavity near the orthosteric binding site pocket; by contrast, lidocaine contacted with all α-subunit loops conforming the ACh binding site, both in α-γ and α-δ and interphases, likely because of its larger size. Together, these results indicate that DEA mimics some, but not all, inhibitory actions of lidocaine on nAChRs and that even this small polar molecule acts by different mechanisms on this receptor. The presented results contribute to a better understanding of the structural determinants of nAChR modulation.

Annotated almanac, 1759

Almanac containing a laid-in leaf and calendar pages with sporadic annotations of measurements, a note of the printer's markings on Winthrop and his wife's watches (January). The laid-in leaf includes personal entries about a measles outbreak (January), the death of his "negro man George" (May 13), the presence of bears in the area (September), the surrender of Quebec (October 16), the heights of Winthrop's son Jemmy and a "new negro boy" named Scipio, and deaths in the community including the burial and baptism statistics for Boston.

Manuscript copy of Joseph Mayhew's complaints against Nathan Prince, Oct. 31, 1740 and Nov. 4, 1740

This is a manuscript copy of meeting minutes concerning fellow Tutor Joseph Mayhew's complaints against Nathan Prince. The minutes are written in a small paper-bound volume whose cover bears these inscriptions: "Oct. 31, 1740. Mr. Mayhew's complaint vs. Mr. Prince to the President and Tutors, Recd 14 Sept. 1741 of a Freshman, seal'd up;" "Acco of Mr. Mayhew's complaint of Mr. Prince contained in the Pres't & Tut's Book;" and "To the Honble Mr. Foxcroft, Chairman of the Committee of the Honble & Revd. the Overseers of Harvard College in Cambridge." Among other complaints, Mayhew was upset that Prince had called him "a Rascall & a rascally Fellow." The minutes also indicate that Prince left two meetings of the President and Tutors without permission, in spite of President Holyoke's having entreated him "Won't you stay?"

Judge's notes on cases heard in Lincoln County (Maine), 1788-1789?

Includes notes and summaries of witnesses' testimony on cases involving contracts and land disputes. One pamphlet bears note "Lincolns. July 7th 1789. Pownalboro. Supreme Court." Pownalborough Court House is in Dresden, Maine, which succeded from Pownalborough. In 1804, the town Pownalborough was renamed Wiscasset.

Dominium temporale non fundatur in gratia (Commencement Quaestiones), 1697 July 7

Small paper notebook of John Ballantine with the handwritten Latin quaestiones performed by Ballantine, Eliphalet Adams, Adam Winthrop, and Jabez Fitch as candidates for the Master’s degree during the July 7, 1697 Harvard Commencement ceremony. The Quaestiones begin with Ballantine’s “Dominum temporal non fundatur in gratia,” and follow with “An Jesuitae possint esse boni subditi? Neg Resp. Dom. Winthrop,” "An Ethnicae virtutes sint verae virtutes?" Neg. Resp. Dom. Adams,” and “An detur omnibus an sufficiens ad salutem? Neg. Resp. Dom. Fitch.” The title page bears the inscription: “Jno Ballantine’s Book” and the first page has been torn out.

Theses of 1663

Handwritten document written in Latin and dated August 1663 purported to be the Harvard College Commencement Theses of 1663, but considered by John Noble of the Colonial Society of Massachusetts to be a contemporary parody. Noble notes of the 1663 Theses, that "there seems to be no reason to doubt that this is a genuine, original manuscript of the date which it bears," but describes it as a "blaze of literary and scholastic pyrotechnics" that suggests it was created satirically (John Noble, "Harvard Theses of 1663" in the Publications of the Colonial Society, Volume V: Transactions, April 1898, pages 322-339).

Palaeoenvironmental and palaeoceanographic changes during the lower to middle Jurassic (Toarcian-Aalenian, ~183-171 Ma). : new evidences from calcareous nannofossils of the Lusitanian Basin

Tese de doutoramento (co-tutela), Geologia (Paleontologia e Estratigrafia), Faculdade de Ciências da Universidade de Lisboa, Université Claude Bernard Lyon 1, 2016

Bosnia, Kosovo and the EU: Is Accession Possible without Full Sovereignty?

Bosnia and Kosovo are the only two members of the EU enlargement zone that have never tried to apply for EU membership, given that both are too far from complying with the required minimum standards. But besides lacking basic capacities, these two potential candidates share another common feature: both are limited, to different degrees, in their national sovereignty. This lack of sovereignty not only limits the capacity of the potential candidates to negotiate or to enter into agreements with the EU; it also undermines their readiness to undertake serious reforms. The EU tries to dodge the political blockades that are the root cause of the problem by focusing on the technical issues; this might provide a temporary relief but cannot substitute a realistic accession perspective, which is currently absent. However, without this perspective, the EU’s ‘normative power’ in these countries will continue to erode – which bears the risk that both Kosovo and Bosnia will, in the end, try to solve existing problems through unilateral measures, such as partition. Given its lack of ability to provide alternatives, the EU has to realistically consider such outcomes and think about the possible consequences.

Rôle de l'isoforme p35 de la chaîne invariante humaine dans la formation et le transport de complexes de CMH II

La présentation antigénique par les molécules de classe II du complexe majeur d’histocompatibilité (CMH II) est un mécanisme essentiel au contrôle des pathogènes par le système immunitaire. Le CMH II humain existe en trois isotypes, HLA-DP, DQ et DR, tous des hétérodimères composés d’une chaîne α et d’une chaîne β. Le CMH II est entre autres exprimé à la surface des cellules présentatrices d’antigènes (APCs) et des cellules épithéliales activées et a pour fonction de présenter des peptides d’origine exogène aux lymphocytes T CD4+. L’oligomérisation et le trafic intracellulaire du CMH II sont largement facilités par une chaperone, la chaîne invariante (Ii). Il s’agit d’une protéine non-polymorphique de type II. Après sa biosynthèse dans le réticulum endoplasmique (ER), Ii hétéro- ou homotrimérise, puis interagit via sa région CLIP avec le CMH II pour former un complexe αβIi. Le complexe sort du ER pour entamer son chemin vers différents compartiments et la surface cellulaire. Chez l’homme, quatre isoformes d’Ii sont répertoriées : p33, p35, p41 et p43. Les deux isoformes exprimées de manière prédominante, Iip33 et p35, diffèrent par une extension N-terminale de 16 acides aminés portée par Iip35. Cette extension présente un motif de rétention au réticulum endoplasmique (ERM) composé des résidus RXR. Ce motif doit être masqué par la chaîne β du CMH II pour permettre au complexe de quitter le ER. Notre groupe s’est intéressé au mécanisme du masquage et au mode de sortie du ER des complexes αβIi. Nous montrons ici que l’interaction directe, ou en cis, entre la chaîne β du CMH II et Iip35 dans une structure αβIi est essentielle pour sa sortie du ER, promouvant la formation de structures de haut niveau de complexité. Par ailleurs, nous démontrons que NleA, un facteur de virulence bactérien, permet d’altérer le trafic de complexes αβIi comportant Iip35. Ce phénotype est médié par l’interaction entre p35 et les sous-unités de COPII. Bref, Iip35 joue un rôle central dans la formation des complexes αβIi et leur transport hors du ER. Ceci fait d’Iip35 un régulateur clef de la présentation antigénique par le CMH II.

The Monetary Policy of the European Central Bank (2002-2015). CEPS Special Report No. 109/May 2015

This paper examines the policies pursued by the European Central Bank (ECB) since the inception of the euro. The ECB was originally set up to pursue price stability, with an eye also to economic growth and financial stability as subsidiary goals, once the primary goal was secured. The application of a single monetary policy to a diverse economic area has entailed a pronounced pro-cyclicality in its real economic effects on the eurozone periphery. Later, monetary policy became the main policy instrument to tackle financial instability elicited by the failure of Lehman Brothers and the sovereign debt crisis in the eurozone. In the process, the ECB emerged as the lender of last resort in the sovereign debt markets of participating countries. Persistent economic depression and deflation eventually brought the ECB into the uncharted waters of unconventional policies. That the ECB could legally perform all of these tasks bears witness to the flexibility of the TFEU and its Statute, but its tools and operating procedures were stretched to their limit. In the end, the place of the ECB amongst EU policy-making institutions has been greatly enhanced, but has entailed repeated intrusions into the broader domain of economic policies – not least because of its market intervention policies – whose consequences have yet to be ascertained.

The Monetary Policy of the European Central Bank (2002-2015). Bruges European Economic Policy Briefings (BEEP) 35/2015.

This paper examines the policies pursued by the European Central Bank (ECB) since the inception of the euro. The ECB was originally set up to pursue price stability, with an eye also to economic growth and financial stability as subsidiary goals, once the primary goal was secured. The application of a single monetary policy to a diverse economic area has entailed a pronounced pro-cyclicality in its real economic effects on the eurozone periphery. Later, monetary policy became the main policy instrument to tackle financial instability elicited by the failure of Lehman Brothers and the sovereign debt crisis in the eurozone. In the process, the ECB emerged as the lender of last resort in the sovereign debt markets of participating countries. Persistent economic depression and deflation eventually brought the ECB into the uncharted waters of unconventional policies. That the ECB could legally perform all of these tasks bears witness to the flexibility of the TFEU and its Statute, but its tools and operating procedures were stretched to their limit. In the end, the place of the ECB amongst EU policy-making institutions has been greatly enhanced, but has entailed repeated intrusions into the broader domain of economic policies – not least because of its market intervention policies – whose consequences have yet to be ascertained.

Russia’s ‘Middle East’: the escalation of religious conflicts in the Northern Caucasus. OSW Commentary Number 207/04.04.2016

The eastern part of the Northern Caucasus (Dagestan, Chechnya and Ingushetia) is becoming an increasingly distinct region in cultural, civilisational and social terms when compared to the rest of the Russian Federation. The situation on the ground there bears greater resemblance to the Middle East than to Russia: Islam is the key factor organising socio-political life, and conflicts inside the Muslim community, often involving bloodshed, are the driving power of developments in the region. The conflict is between the two main branches of Islam in the Northern Caucasus: Sufism linked to the official clergy and government, and Salafism which is gaining more and more supporters among young people in the Caucasus. Tension, including clashes over mosques, attacks, mass detentions, etc. has been observed mainly in Dagestan and Ingushetia.