The Role of Male Flight Performance in the Evolution of Extreme Sexual Dimorphism in Leaf Insects

In many insect groups, males display a smaller size than their respective females. While selection of larger sizes through fecundity benefits is rather well understood in females of such systems, selection for smaller sizes in males through increased mobility is often evoked but rarely tested empirically. I studied the relationship between male body size and flight performance in males of the leaf insect Phyllium Philippinicum to determine if larger males indeed display reduced mobility. With graduate student Romain Boisseau, we recorded videos of 17 individuals flying in ultra slow motion and used Matlab to mark the head and the tail tip in each frame. Through these trajectories, we are able to measure velocity and body angle using R. Our results showed that smaller males had higher maneuverability, maximum vertical velocity, and mean stable velocity, thus demonstrating that they are better fliers than larger males

Triptolide exhibits anti-inflammatory, anti-catabolic as well as anabolic effects and suppresses TLR expression and MAPK activity in IL-1β treated human intervertebral disc cells

Introduction: Increased levels of proinflammatory cytokines seem to play a pivotal role in the development of back pain in a subpopulation of patients with degenerative intervertebral disc (IVD) disease. As current treatment options are mostly limited to surgical interventions or conservative treatment, anti-inflammatory substances might offer a novel, more target-orientated therapeutic approach. Triptolide (TPL), a natural substance found in the Chinese medicinal herb Tripterygium wilfordii Hook, has been demonstrated to possess anti-inflammatory effects in various cells, but no studies exist so far for the IVD. Therefore, the aim of this study was to determine the effects of TPL on human IVD cells by analyzing changes in gene expression and underlying molecular mechanisms. Materials and methods: In order to investigate the anti-inflammatory, anabolic and anti-catabolic effect of TPL, dose-dependency experiments (n=5) and time course experiments (n=5) were performed on IL-1β prestimulated human IVD cells and changes in gene expression of IL-6/-8, TNF-α, PGE2S, MMP1/2/3/13, aggrecan and collagen-I/-II were analyzed by real-time RT-PCR. The molecular mechanisms underlying the effects observed upon TPL treatment were investigated by analyzing involvement of Toll-like receptors TLR2/4 (real-time RT-PCR, n=5), NF-κB, MAP kinases p38, ERK and JNK (immunoblotting and immunocytochemistry, n=4) as well as RNA polymerase II (immunoblotting, n=3). Results: Results showed that 50nM TPL exhibited an anti-inflammatory, anti-catabolic and anabolic effect on the mRNA level for IL-6/-8, PGE2S, MMP1/2/3/13, aggrecan, collagen-II and TLR2/4, with most pronounced changes after 18h for proinflammatory cytokines and MMPs or 30h for TLRs and matrix proteins. However, we also observed an up-regulation of TNF-α at higher concentrations. The effects of TPL did not seem to be mediated via an inhibition of NF-κB or a decrease of RNA polymerase II levels, but TPL influenced activity of MAP kinases p38 and ERK (but not JNK) and expression of TLR2/4. Conclusions: In conclusion, TPL may possess promising potential for the treatment of inflammation-related discogenic back pain in vitro, but its analgetic effect will need to be confirmed in an appropriate in vivo animal mode

Breakdown of the Isobaric Multiplet Mass Equation for the A = 20 and 21 Multiplets

Using the Penning trap mass spectrometer TITAN, we performed the first direct mass measurements of 20,21Mg, isotopes that are the most proton-rich members of the A = 20 and A = 21 isospin multiplets. These measurements were possible through the use of a unique ion-guide laser ion source, a development that suppressed isobaric contamination by six orders of magnitude. Compared to the latest atomic mass evaluation, we find that the mass of 21Mg is in good agreement but that the mass of 20Mg deviates by 3{\sigma}. These measurements reduce the uncertainties in the masses of 20,21Mg by 15 and 22 times, respectively, resulting in a significant departure from the expected behavior of the isobaric multiplet mass equation in both the A = 20 and A = 21 multiplets. This presents a challenge to shell model calculations using either the isospin non-conserving USDA/B Hamiltonians or isospin non-conserving interactions based on chiral two- and three-nucleon forces.Comment: 5 pages, 2 figure

Electricity Planning for Sustainable Development in the MENA Region. Criteria and indicators for conducting a sustainability assessment of different electricity generation technologies in Morocco, Jordan and Tunisia

The governments of Morocco, Jordan and Tunisia currently stand at a crossroads for new electricity pathways. While the deployment of renewable energies is receiving policy support across the region, fossil fuels—especially coal and natural gas—as well as nuclear power are prominent alternatives in the countries’ development plans. This crossroads offers a unique opportunity to provide scientifically sound information on how to expand future electricity generation capacities in ways that are sensitive to the myriad of development challenges while avoiding a lock-in of the power sector in unsustainable pathways. As electricity systems are not developed in isolation from society, but in a continuous interaction with social, economic, environmental, and political dimensions, this publication aims to develop a comprehensive database for the purpose of evaluating the complex trade-offs between different electricity generation technologies and sustainable development at the national and local level in Morocco, Jordan and Tunisia. By shedding light on the intersection between electricity generation technologies, sustainable development and society, the results of this publication are intended to complement previous research on energy systems—that either focused on singular aspects of sustainable development, techno–economic aspects of electricity systems or on selected electricity technologies—with the "societal element" in electricity planning. Taken up by policymakers, project developers, civil society organization and researchers, the database of this document is furthermore envisioned to help in paving the way towards an energy system that is not only reliable, affordable and accessible but also socially robust and that contributes to sustainable development in Morocco, Jordan and Tunisia

Low-Background In-Trap Decay Spectroscopy with TITAN at TRIUMF

An in-trap decay spectroscopy setup has been developed and constructed for use with the TITAN facility at TRIUMF. The goal of this device is to observe weak electron-capture (EC) branching ratios for the odd-odd intermediate nuclei in the $\beta\beta$ decay process. This apparatus consists of an up-to 6 Tesla, open-access spectroscopy ion-trap, surrounded radially by up to 7 planar Si(Li) detectors which are separated from the trap by thin Be windows. This configuration provides a significant increase in sensitivity for the detection of low-energy photons by providing backing-free ion storage and eliminating charged-particle-induced backgrounds. An intense electron beam is also employed to increase the charge-states of the trapped ions, thus providing storage times on the order of minutes, allowing for decay-spectroscopy measurements. The technique of multiple ion-bunch stacking was also recently demonstrated, which further extends the measurement possibilities of this apparatus. The current status of the facility and initial results from a $^{116}$In measurement are presented.Comment: Proceedings for the 2nd International Conference on Advances in Radioactive Isotope Science (ARIS2014

Precision mass measurements of magnesium isotopes and implications on the validity of the Isobaric Mass Multiplet Equation

If the mass excess of neutron-deficient nuclei and their neutron-rich mirror partners are both known, it can be shown that deviations of the Isobaric Mass Multiplet Equation (IMME) in the form of a cubic term can be probed. Such a cubic term was probed by using the atomic mass of neutron-rich magnesium isotopes measured using the TITAN Penning trap and the recently measured proton-separation energies of $^{29}$Cl and $^{30}$Ar. The atomic mass of $^{27}$Mg was found to be within 1.6$\sigma$ of the value stated in the Atomic Mass Evaluation. The atomic masses of $^{28,29}$Mg were measured to be both within 1$\sigma$, while being 8 and 34 times more precise, respectively. Using the $^{29}$Mg mass excess and previous measurements of $^{29}$Cl we uncovered a cubic coefficient of $d$ = 28(7) keV, which is the largest known cubic coefficient of the IMME. This departure, however, could also be caused by experimental data with unknown systematic errors. Hence there is a need to confirm the mass excess of $^{28}$S and the one-neutron separation energy of $^{29}$Cl, which have both come from a single measurement. Finally, our results were compared to ab initio calculations from the valence-space in-medium similarity renormalization group, resulting in a good agreement.Comment: 7 pages, 3 figure

Triangle-Free Penny Graphs: Degeneracy, Choosability, and Edge Count

We show that triangle-free penny graphs have degeneracy at most two, list coloring number (choosability) at most three, diameter $D=\Omega(\sqrt n)$, and at most $\min\bigl(2n-\Omega(\sqrt n),2n-D-2\bigr)$ edges.Comment: 10 pages, 2 figures. To appear at the 25th International Symposium on Graph Drawing and Network Visualization (GD 2017