Dimethyl fumarate: a new oral treatment option for multiple sclerosis

Multiple Sclerosis (MS) is a slowly progressive, immunologically mediated disease of the CNS. The recent years have witnessed great efforts in establishing new therapeutic options for multiple sclerosis. There is a clear need for more effective, safe and at the same time orally available treatment options. Here we review the recently approved drug Dimethyl fumarate (DMF, Tecfidera®) as a new therapeutic option for MS and its role in context to the existing oral treatment options for MS. Dimethyl fumarate is the methyl ester of fumaric acid and has been claimed to possess immunomodulatory properties and is already in clinical use as Fumaderm for severe systemic psoriasis. In addition, Dimethyl fumarate was also shown to act on the blood-brain barrier and exert neuroprotective properties via activation of anti-oxidative pathways and displayed beneficial effects in experimental autoimmune encephalomyelitis (EAE), a model mimicking many aspects of MS. Based on two global phase III studies. Dimethyl fumarate has been clinically proven to significantly reduce important measures of disease activity, including relapses and development of brain lesions, as well as to slow disability progression over time, while demonstrating a favourable safety and tolerability profile

Primordial black hole formation with non-Gaussian curvature perturbations

In the context of transient constant-roll inflation near a local maximum, we derive the non-perturbative field redefinition that relates a Gaussian random field with the true non-Gaussian curvature perturbation. Our analysis shows the emergence of a new critical amplitude $\zeta_*$, corresponding to perturbations that prevent the inflaton from overshooting the local maximum, thus becoming trapped in the false minimum of the potential. For potentials with a mild curvature at the local maximum (and thus small non-Gaussianity), we recover the known perturbative field redefinition. We apply these results to the formation of primordial black holes, and discuss the cases for which $\zeta_*$ is smaller or of the same order than the critical value for collapse of spherically symmetric overdensities. In the latter case, we present a simple potential for which the power spectrum needs an amplitude 10 times smaller that in the Gaussian case for producing a sizeable amount of primordial black holes.Comment: 13 pages, 8 figures. v2: expanded explanations + small changes. v3: small typos correcte

The two-field regime of natural inflation

The simplest two-field completion of natural inflation has a regime in which both fields are active and in which its predictions are within the Planck 1-$\sigma$ confidence contour. We show this for the original model of natural inflation, in which inflation is achieved through the explicit breaking of a U(1) symmetry. We consider the case in which the mass coming from explicit breaking of this symmetry is comparable to that from spontaneous breaking, which we show is consistent with a hierarchy between the corresponding energy scales. While both masses are comparable when the observable modes left the horizon, the mass hierarchy is restored in the last e-foldings of inflation, rendering the predictions consistent with the isocurvature bounds. For completeness, we also study the predictions for the case in which there is a large hierarchy of masses and an initial period of inflation driven by the (heavy) radial field.Comment: 18 pages, 9 figure

New Century, Old Disparities: Gender and Ethnic Wage Gaps in Latin America

This paper surveys gender and ethnic wage gaps in 18 Latin American countries, decomposing differences using matching comparisons as a non-parametric alternative to the Blinder-Oaxaca (BO) decomposition. It is found that men earn 9-27 percent more than women, with high cross-country heterogeneity. The unexplained pay gap is higher among older, informal and self-employed workers and those in small firms. Ethnic wage differences are greater than gender differences, and educational attainment differentials play an important role in explaining the gap. Higher ethnic wage gaps are found among males, single-income generators of households and full-time workers, and in rural areas. An important share of the ethnic wage gap is due to the scarcity of minorities in high-paid positions.gender, ethnicity, wage gaps, Latin America, matching

Cumulative effects in inflation with ultra-light entropy modes

In multi-field inflation one or more non-adiabatic modes may become light, potentially inducing large levels of isocurvature perturbations in the cosmic microwave background. If in addition these light modes are coupled to the adiabatic mode, they influence its evolution on super horizon scales. Here we consider the case in which a non-adiabatic mode becomes approximately massless ("ultralight") while still coupled to the adiabatic mode, a typical situation that arises with pseudo-Nambu-Goldstone bosons or moduli. This ultralight mode freezes on super-horizon scales and acts as a constant source for the curvature perturbation, making it grow linearly in time and effectively suppressing the isocurvature component. We identify a Stuckelberg-like emergent shift symmetry that underlies this behavior. As inflation lasts for many e-folds, the integrated effect of this source enhances the power spectrum of the adiabatic mode, while keeping the non-adiabatic spectrum approximately untouched. In this case, towards the end of inflation all the fluctuations, adiabatic and non-adiabatic, are dominated by a single degree of freedom.Comment: 27 pages, 1 figure; v2: improved discussions, version published in JCA

Efficient Implementation of IEEE 802.11i Wi-Fi Security (WPA2-PSK) Standard Using FPGA

The rationale behind the thesis was to design efficient implementations of cryptography algorithms used for Wi-Fi Security as per IEEE 802.11i Wi-Fi Security (WPA2-PSK) standard. The focus was on software implementation of Password-Based Key Derivation Function 2 (PBKDF2) using Keyed-Hash Message Authentication Code (HMAC)-SHA1, which is used for authentication, and, hardware implementation of AES-256 cipher, which is used for data confidentiality. In this thesis, PBKDF2 based on HMAC-SHA1 was implemented on software using C programming language, and, AES-256 was implemented on hardware using Verilog HDL. The overall implementation was designed and tested on Nexys4 FPGA board. The performance of the implementation was compared with other existing designs. Latency (us) was used as the performance metric for PBKDF2, whereas, throughput (Gb/s), resource utilization (Number of Slices), efficiency (Kb/s per slice) and latency (ns) were used as performance metrics for AES-256. MRF24WG0MA PMOD Wi-Fi module was the 2.4 GHz Wi-Fi module which was interfaced with Nexys4 FPGA board for wireless communication. When the correct security credentials were entered in the implemented system interfaced to the Wi-Fi module, it was successfully authenticated by a 2.4 GHz wireless router (or mobile hotspot) configured to work in WPA2-PSK security mode. Once this system was authenticated, the implemented AES-256 cipher within the system was used to provide a layer of encryption over the data being communicated in the network

The Big Mac Index And Real-Income Disparity

The Big Mac Index was introduced to (semi-humorously) test the theory of purchasing power parity and measure the disparity in currency values. Instead, in this paper, we consider this index to find out the per capita real-income disparity across 54 countries. We find that the per capita real-income can be very low in some countries even when Big Mac burgers are very cheap, like in India. Among these countries, Hong Kong’s per capita Big Mac affordability is the highest with 47 burgers daily whereas Pakistan’s people could afford just one a day. Additionally, we find that Russia and China’s Big Mac affordability has been significantly increasing over the last decade, Brazil’s has remained more or less constant, however USA’s Big Mac affordability has been falling, indicating that per capita real-income of Americans has been decreasing over the last decade. Finally, we find that increased role of the government might be negatively correlated to per capita real-income. Czech Republic has been experiencing increased Big Mac affordability as the country has been reducing the government’s role; whereas Argentina has been experiencing reduced Big Mac affordability as the country has been moving left and increasing the government’s power

Literacy Traps: Society-wide Education and Individual Skill Premia

Using a model of O-ring production function, the paper demonstrates how certain communities can get caught in a low-literacy trap in which each individual finds it not worthwhile investing in higher skills because others are not high-skilled. The model sheds light on educational policy. It is shown that policy for promoting human capital has to take the form of a mechanism for solving the coordination failure in people’s choice of educational strategy.education, literacy, O-ring, skill formation, traps