French intervention in Africa reflects its national politics

Eva Nelson analyses the underlying motivations in France’s foreign policy towards Africa

Publication of original research in urologic journals - a neglected orphan?

The pathophysiologic mechanisms behind urologic disease are increasingly being elucidated. The object of this investigation was to evaluate the publication policies of urologic journals during a period of progressively better understanding and management of urologic disease. Based on the ISI Web of Knowledge Journal Citation Reports and the PubMed database, the number and percentage of original experimental, original clinical, review or commentarial articles published between 2002–2010 in six leading urologic journals were analyzed. “British Journal of Urology International”, “European Urology”, “Urologic Oncology-Seminars and Original Investigations” (“Urologic Oncology”), “Urology”, “The Journal of Urology”, and “World Journal of Urology” were chosen, because these journals publish articles in all four categories. The publication policies of the six journals were very heterogeneous during the time period from 2002 to 2010. The percentage of original experimental and original clinical articles, related to all categories, remained the same in “British Journal of Urology International”, “Urologic Oncology”, “Urology” and “The Journal of Urology”. The percentage of experimental reports in “World Journal of Urology” between 2002–2010 significantly increased from 10 to 20%. A distinct elevation in the percentage of commentarial articles accompanied by a reduction of clinical articles became evident in “European Urology” which significantly correlated with a large increase in the journal’s impact factor. No clearly superior policy could be identified with regard to a general increase in the impact factors from all the journals. The publication policy of urologic journals does not expressly reflect the increase in scientific knowledge, which has occurred over the period 2002–2010. One way of increasing the exposure of urologists to research and expand the interface between experimental and clinical research, would be to enlarge the percentage of experimental articles published. There is no indication that such policy would be detrimental to a journal’s impact factor

Resistance after chronic application of the HDAC-inhibitor valproic acid is associated with elevated Akt activation in renal cell carcinoma in vivo

Targeted drugs have significantly improved the therapeutic options for advanced renal cell carcinoma (RCC). However, resistance often develops, negating the benefit of these agents. In the present study, the molecular mechanisms of acquired resistance towards the histone deacetylase (HDAC) inhibitor valproic acid (VPA) in a RCC in vivo model were investigated. NMRI:nu/nu mice were transplanted with Caki-1 RCC cells and then treated with VPA (200 mg/kg/day). Controls remained untreated. Based on tumor growth dynamics, the mice were divided into “responders” and “non-responders” to VPA. Histone H3 and H4 acetylation and expression of cell signaling and cell cycle regulating proteins in the RCC mouse tumors were evaluated by Western blotting. Tumor growth of VPA responders was significantly diminished, whereas that of VPA non-responders even exceeded control values. Cdk1, 2 and 4 proteins were strongly enhanced in the non-responders. Importantly, Akt expression and activity were massively up-regulated in the tumors of the VPA non-responders. Chronic application (12 weeks) of VPA to Caki-1 cells in vitro evoked a distinct elevation of Akt activity and cancer cells no longer responded with cell growth reduction, compared to the short 2 week treatment. We assume that chronic use of an HDAC-inhibitor is associated with (re)-activation of Akt, which may be involved in resistance development. Consequently, combined blockade of both HDAC and Akt may delay or prevent drug resistance in RCC

Wide Band Interaction Impedance and Mode Excitation in Glide Symmetric Double Corrugated Waveguides for mm-wave TWTs

Focusing on traveling wave tube (TWT) applications, the interaction impedance between an electron beam and electromagnetic modes in three distinct, but related, corrugated waveguides that operate at millimeter waves is investigated together with the role of glide symmetry. Two waveguide structures have glide symmetry, and the irreducible Brillouin zone is related to half of the period, leading to a wide band linearity, i.e., nondispersive, property of the dispersion diagram. The investigation on the modes with longitudinal electric field that can be excited shows that the bottom-top glide (BT Glide) symmetric corrugated waveguide has a wide band interaction impedance, hence it is a good candidate for millimeter wave TWT amplifiers. Furthermore, the backward electromagnetic mode in such BT Glide slow wave structure is not $z$ polarized, eliminating the {risk} of backward wave oscillations.Comment: Eight figures, eight page

Catches composition and discards generated by hake Merluccius hubbsi and shrimp Pleoticus muelleri fisheries: a case of study in the high-sea ice trawlers of San Jorge Gulf, Chubut, Argentina

La pesca de arrastre de fondo es el arte más utilizado a nivel mundial generando grandes cantidades de descarte por la captura incidental de una amplia variedad de especies. En el Golfo San Jorge en la Patagonia Argentina, opera una flota fresquera de altura cuya especie objetivo es la merluza Merluccius hubbsi, alternando con mareas a langostino Pleoticus muelleri. La información para el presente estudio abarca un periodo de 10 años (2003-2012) y fue obtenida por el Programa de Observadores a Bordo de la Provincia del Chubut (POBCh). Se identificaron un total de 90 taxones, 33 invertebrados, 34 peces óseos y 22 peces cartilaginosos. Los análisis multivariados describen 2 agrupamientos, el primero cuando la especie objetivo fue la merluza y el otro cuando la especie objetivo fue langostino. Cuando la especie objetivo fue la merluza la composición de las capturas varió según las áreas de pesca aunque no se observó este patrón cuando la especie objetivo fue el langostino, con distintos números de taxones el norte y el centro del golfo (norte: merluza 79 taxones, langostino 71; centro: merluza 60 taxones, langostino 50). En la flota fresquera de altura, el aprovechamiento de las especies capturadas fue integral cuando la pesca estuvo dirigida a merluza, en cambio cuando el objetivo fue el langostino se descartaron la mayoría de los taxones. El presente trabajo caracteriza la composición de las capturas en la flota fresquera de altura del Golfo San Jorge, describe las especies capturadas cuando el esfuerzo estuvo dirigido a merluza o langostino, analiza las frecuencias de ocurrencia y abundancias y describe el aprovechamiento de los distintos taxones identificados.The bottom trawling is the word most used fishing art generating large amounts of discards and incidental captures with a wide variety of species. In the San Jorge Gulf Argentine Patagonia, operates a fleet whose target specie is the hake Merluccius hubbsi , alternating with red shrimp Pleoticus muelleri. The information for this study covers a period of 10 years (2003-2012) and was collected by the On-board Observer Program of the Chubut Province (POBCh). Were identified a total of 90 taxa, 33 invertebrates, 34 osteichthyes and 22 chondrichthyes. Multivariate analysis indicated differences in the composition of the catch when the target species was shrimp or hake. When the target species was the hake catch composition varied by fishing areas, this pattern was not observed when the target species was the shrimp, with different numbers of taxa in the northern and central Gulf (north: hake 79 taxa, shrimp 71, center: hake 60 taxa, shrimp 50). The utilization of different species caught when the fleet operated on hake was integral, however when the fleet operated on shrimp most of the taxa were discarded. This study characterized the composition of the fleet catches at San Jorge Gulf, described the species caught when the fleet operates on hake or shrimp, analyzes the frequency of occurrence and abundance and describes the use of different taxa identified.Fil: Bovcon, Nelson Darío. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Trelew; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Góngora, María Eva. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Trelew; ArgentinaFil: Marinao, Cristian Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Gonzalez Zevallos, Diego Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentin

Estradiol suppresses tissue androgens and prostate cancer growth in castration resistant prostate cancer

<p>Abstract</p> <p>Background</p> <p>Estrogens suppress tumor growth in prostate cancer which progresses despite anorchid serum androgen levels, termed castration resistant prostate cancers (CRPC), although the mechanisms are unclear. We hypothesize that estrogen inhibits CRPC in anorchid animals by suppressing tumoral androgens, an effect independent of the estrogen receptor.</p> <p>Methods</p> <p>The human CRPC xenograft LuCaP 35V was implanted into orchiectomized male SCID mice and established tumors were treated with placebo, 17β-estradiol or 17β-estradiol and estrogen receptor antagonist ICI 182,780. Effects of 17β-estradiol on tumor growth were evaluated and tissue testosterone (T) and dihydrotestosterone (DHT) evaluated by mass spectrometry.</p> <p>Results</p> <p>Treatment of LuCaP 35V with 17β-estradiol slowed tumor growth compared to controls (tumor volume at day 21: 785 ± 81 mm³vs. 1195 ± 84 mm³, p = 0.002). Survival was also significantly improved in animals treated with 17β-estradiol (p = 0.03). The addition of the estrogen receptor antagonist ICI 182,780 did not significantly change survival or growth. 17β-estradiol in the presence and absence of ICI 182,780 suppressed tumor testosterone (T) and dihydrotestosterone (DHT) as assayed by mass spectrometry. Tissue androgens in placebo treated LuCaP 35V xenografts were; T = 0.71 ± 0.28 pg/mg and DHT = 1.73 ± 0.36 pg/mg. In 17β-estradiol treated LuCaP35V xenografts the tissue androgens were, T = 0.20 ± 0.10 pg/mg and DHT = 0.15 ± 0.15 pg/mg, (p < 0.001 vs. controls). Levels of T and DHT in control liver tissue were < 0.2 pg/mg.</p> <p>Conclusions</p> <p>CRPC in anorchid animals maintains tumoral androgen levels despite castration. 17β-estradiol significantly suppressed tumor T and DHT and inhibits growth of CRPC in an estrogen receptor independent manner. The ability to manipulate tumoral androgens will be critical in the development and testing of agents targeting CRPC through tissue steroidogenesis.</p

Satellites of Milky Way- and M31-like galaxies with TNG50: Quenched fractions, gas content, and star formation histories

We analyse the quenched fractions, gas content, and star formation histories of ∼1200 satellite galaxies with M* ≥ 5 × 106 M⊙ around 198 Milky Way- (MW) and Andromeda-like (M31) hosts in TNG50, the highest-resolution simulation of IllustrisTNG. Satellite quenched fractions are larger for smaller masses, for smaller distances to their host galaxy, and in the more massive M31-like compared to MW-like hosts. As satellites cross their host’s virial radius, their gas content drops: most satellites within 300 kpc lack detectable gas reservoirs at z = 0, unless they are massive like the Magellanic Clouds and M32. Nevertheless, their stellar assembly exhibits a large degree of diversity. On average, the cumulative star formation histories are more extended for brighter, more massive satellites with a later infall, and for those in less massive hosts. Based on these relationships, we can even infer infall periods for observed MW and M31 dwarfs: e.g. 0–4 Gyr ago for the Magellanic Clouds and Leo I, 4 − 8 and 0–2 Gyr ago for M32 and IC 10, respectively. Ram pressure stripping (in combination with tidal stripping) deprives TNG50 satellites of their gas reservoirs and ultimately quenches their star formation, even though only a few per cent of the present-day satellites around the 198 TNG50 MW/M31-like hosts appear as jellyfish. The typical time since quenching for currently quenched TNG50 satellites is 6.9+2.5−3.3 Gyr ago. The TNG50 results are consistent with the quenched fractions and stellar assembly of observed MW and M31 satellites, however, satellites of the SAGA survey with M* ∼ 108 − 9 M⊙ exhibit lower quenched fractions than TNG50 and other, observed analogues

Sustainable Materials and Chemical Processes for Additive Manufacturing

Unformatted postprintAdditive manufacturing (AM) is energizing the fields of chemistry and materials science to develop new inks for new applications within fields such as aerospace, robotics, and healthcare. AM enables the fabrication of innumerable 3D geometries that cannot be easily produced by other means. In spite of the great promise of AM as an advanced form of future manufacturing, there are still fundamental challenges with respect to sustainability that need to be addressed. Some of the material needs for AM include sustainable sources of printing inks, resins, and filaments, as well as pathways for polymer recycling, upcycling, and chemical circularity. Furthermore, the combination of bio-sourced and biodegradable polymers with additive manufacturing could enable the fabrication of objects that can be recycled back into feedstock or degraded into non-toxic products after they have served their function. Herein, we review the recent literature on the design and chemistry of the polymers to that enable sustainability within the field of AM, with a particular focus on biodegradable and bio-sourced polymers. We also discuss some of the sustainability-related applications that have emerged as a result of AM technologies.E.S.-R. thanks the European funding by the Marie Sklodowska-Curie Individual Fellowships (MSCA-IF-GF) 841879-4D Biogel. H.S. and C.J. thank MINECO for funding through MAT2017-83373-R. A.N. thanks the National Science Foundation for support (1752972)

Mechanical Properties and Corrosion Behaviour of Nanostructured Cu-rich CuNi Electrodeposited Films

Nanocrystalline Cu-rich CuNi alloy thin films (with copper content ranging from 22 to 97 at%) have been grown by electrodeposition, using galvanostatic conditions in an electrolytic bath containing Ni and Cu sulphates with a [Ni(II)]/[Cu(II)] molar ratio of 11. The Cu content is tuned by varying the applied current density during deposition. The nanoscrystalline nature of Cu-rich CuNi thin films has been achieved using saccharine as a grain refinement agent, although for high Cu content (> 90 at%) the refinement effect is less pronounced. Due to the nanocrystalline character of the films, low surface roughness, good compactness, and outstanding mechanical properties (e.g. nanoindentation hardness values off approximately 7 GPa) are obtained, particularly for Cu percentages below 70 at%. The presence of stacking faults also contributes to the observed high strength. The films show good corrosion protective behaviour in a 3.5 wt% NaCl medium, with corrosion potentials more positive than the bare substrate (pure-Cu) and lower corrosion current density values ranging from 1.8 to 5.4 [mi]A/square centimeter