Impact evaluation of trade interventions : paving the way

The focus of trade policy has shifted in recent years from economy-wide reductions in tariffs and trade restrictions toward targeted interventions to facilitate trade and promote exports. Most of these latter interventions are based on the new mantra of"aid-for-trade"rather than on hard evidence on what works and what does not. On the one hand, rigorous impact-evaluation is needed to justify these interventions and to improve their design. On the other hand, rigorous evaluation is feasible because unlike traditional trade policy, these interventions tend to be targeted and so it is possible to construct treatment and control groups. When interventions are not targeted, such as in the case of customs reforms, some techniques, such as randomized control trials, may not be feasible but meaningful evaluation may still be possible. Theis paper discusses examples of impact evaluations using a range of methods (experimental and non-experimental), highlighting the particular issues and caveats arising in a trade context, and the valuable lessons that are already being learned. The authors argue that systematically building impact evaluation into trade projects could lead to better policy design and a more credible case for"aid-for-trade."Economic Theory&Research,Trade Policy,Transport Economics Policy&Planning,Poverty Monitoring&Analysis,Free Trade

Composition−Structure Relationships in Polar Intermetallics: Experimental and Theoretical Studies of LaNi1+xAl6-x (x = 0.44)

A new ternary aluminide, LaNi1+xAl6-x (x = 0.44), has been synthesized from La, Ni, and Al in sealed silica tubes. Its structure, determined by single-crystal X-ray diffraction, is tetragonal P4/mmm (No. 123) with Z = 1 and has the lattice parameters a = 4.200(8) and c = 8.080(8) Å. Refinement based on Fo2 yielded R1 = 0.0197 and wR2 = 0.020 [I \u3e 2σ(I)]. The compound adopts a structure type previously observed in SrAu2Ga5 and EuAu2Ga5. The atomic arrangement is closely related to the one in BaAl4 as well as in other rare-earth gallide compounds such as LaNi0.6Ga6, HoCoGa5, Ce4Ni2Ga20, Ce4Ni2Ga17, Ce4NiGa18, and Ce3Ni2Ga15. This structure exhibits a large open cavity which may be filled by a guest atom. Band structure calculations using density functional theory have been carried out to understand the stability of this new compound

Crystallographic, Electronic, and Magnetic Studies of ζ2-GaM (M = Cr, Mn or Fe): Trends in Itinerant Magnetism

This study of the crystal structure, electronic structure, and magnetic properties of the ζ2-GaM (M = Cr, Mn or Fe) alloys is motivated by the recent reinvestigation of the crystallographic Al8Cr5 structure type of ζ2-GaMn. The isostructural compounds ζ2-GaFe and ζ2-GaCr have been refined using X-ray powder diffraction as well as neutron powder diffraction for ζ2-GaFe. Their structures have been refined using the space group R3̄m, with cell parameters a = 12.625(8) Å and c = 7.785(10) Å for ζ2-GaCr and a = 12.4368(11) Å and c = 7.7642(10) Å for ζ2-GaFe. Band structure calculations using the self-consistent, spin-polarized TB-LMTO method were performed to understand their electronic structure and magnetic properties. Band calculations show that from GaCr to GaFe the magnetic interactions change from weakly antiferromagnetic coupling to ferromagnetic coupling. Magnetic measurements confirm ferromagnetism for GaFe and show a weak paramagnetic response for GaCr

Structure Determination of Two Modulated γ-Brass Structures in the Zn−Pd System through a (3 + 1)-Dimensional Space Description

The structure determination of two composite compounds in the Zn−Pd system with close relationships to the cubic γ-brass structure Zn11−δPd2+δ is reported. Their structures have been solved from single crystal X-ray diffraction data within a (3 + 1)-dimensional [(3 + 1)D] formalism. Zn75.7(7)Pd24.3 and Zn78.8(7)Pd21.2 crystallize with orthorhombic symmetry, superspace group Xmmm(00γ)0s0 (X = [(1/2,1/2,0,0); (0,1/2,1/2,1/2); (1/2,0,1/2,1/2)]), with the following lattice parameters, respectively: as = 12.929(3) Å, bs = 9.112(4) Å, cs = 2.5631(7) Å, q = 8/13 c* and Vs = 302.1(3) Å3 and as = 12.909(3) Å, bs = 9.115(3) Å, cs = 2.6052(6) Å, q = 11/18 c* and Vs = 306.4(2) Å3. Their structures may be considered as commensurate because they can be refined in the conventional 3D space groups (Cmce and Cmcm, respectively) using supercells, but they also refined within the (3 + 1)D formalism to residual factors R = 3.14% for 139 parameters and 1184 independent reflections for Zn75.7(7)Pd24.3 and R = 3.16% for 175 parameters and 1804 independent reflections for Zn78.8(7)Pd21.2. The use of the (3 + 1)D formalism improves the results of the refinement and leads to a better understanding of the complexity of the atomic arrangement through the various modulations (occupation waves and displacive waves). Our refinements emphasize a unique Pd/Zn occupancy modulation at the center of distorted icosahedra, a modulation which correlates with the distortion of these polyhedra

Safety enhancement by transposition of the nitration of toluene from semi-batch reactor to continuous intensified heat exchanger reactor

The behaviour of a continuous intensified heat exchanger (HEX) reactor in case of process failure is analysed and compared to the behaviour of a semi-continuous reactor. The nitration of toluene is considered as test reaction to identify the main failure scenarios that can lead to thermal runaway in both processes using the HAZOP method.No flow rate of process fluid and utility fluid in the continuous process. No stirring during feeding of the reactor followed by normal stirring for the semi-continuous reactor. These scenarios are simulated for both processes and the temperature profiles are observed. This study shows that the temperature is better controlled in the continuous process because of the intrinsic characteristics of the HEX reactor. In fact, this device has a low reactive volume relative to the mass of the reactor, allowing a good dissipation of the heat produced by the reaction, even in case of failure. This characteristic of the intensified reactor is confirmed by an experimental work

Atomic Distributions in the γ-Brass Structure of the Cu−Zn System: A Structural and Theoretical Study

The crystal structures, atomic distributions, and theoretical electronic structures of five different Cu5-xZn8+x γ-brass compounds (x = −0.59(3), −0.31(3), 0.00(3), 0.44(3), and 0.79(3)) are reported with the goal of identifying chemical influences on the observed phase width. These structures have been refined by both neutron and X-ray powder diffraction to obtain accurate crystal chemical parameters. All compounds crystallize in the space group I4̄3m (No. 217) (Z = 4), and the unit cell parameters are a = 8.8565(4), 8.8612(5), 8.8664(3) , 8.8745(4), and 8.8829(7) Å, respectively, for Cu5.59Zn7.41, Cu5.31Zn7.69, Cu5.00Zn8.00, Cu4.56Zn8.44, and Cu4.21Zn8.79. The results indicate specific site substitutions on both sides of the ideal composition “Cu5Zn8”. In all cases, the 26-atom cluster building up the γ-brass structure shows a constant inner [Cu4Zn4] tetrahedral star with compositional variation occurring at the outer octahedron and cuboctahedron. First principles and semiempirical electronic structure calculations using both a COHP and Mulliken population analysis were performed to understand the observed compositional range and to address the “coloring problem” for the site preferences of Cu and Zn atoms for this series of compounds

Obesity-dependent changes in interstitial ECM mechanics promote breast tumorigenesis.

Obesity and extracellular matrix (ECM) density are considered independent risk and prognostic factors for breast cancer. Whether they are functionally linked is uncertain. We investigated the hypothesis that obesity enhances local myofibroblast content in mammary adipose tissue and that these stromal changes increase malignant potential by enhancing interstitial ECM stiffness. Indeed, mammary fat of both diet- and genetically induced mouse models of obesity were enriched for myofibroblasts and stiffness-promoting ECM components. These differences were related to varied adipose stromal cell (ASC) characteristics because ASCs isolated from obese mice contained more myofibroblasts and deposited denser and stiffer ECMs relative to ASCs from lean control mice. Accordingly, decellularized matrices from obese ASCs stimulated mechanosignaling and thereby the malignant potential of breast cancer cells. Finally, the clinical relevance and translational potential of our findings were supported by analysis of patient specimens and the observation that caloric restriction in a mouse model reduces myofibroblast content in mammary fat. Collectively, these findings suggest that obesity-induced interstitial fibrosis promotes breast tumorigenesis by altering mammary ECM mechanics with important potential implications for anticancer therapies

Structurally Simple Osmium(II) Polypyridyl Complexes as Photosensitizers for Photodynamic Therapy in the Near Infrared**

Five osmium(II) polypyridyl complexes of the general formula [Os(4,7‐diphenyl‐1,10‐phenanthroline)$_{2}$L]$^{2+}$ were synthesized as photosensitizers for photodynamic therapy by varying the nature of the ligand L. Thanks to the pronounced π‐extended structure of the ligands and the heavy atom effect provided by the osmium center, these complexes exhibit a high absorption in the near‐infrared (NIR) region (up to 740 nm), unlike related ruthenium complexes. This led to a promising phototoxicity in vitro against cancer cells cultured as 2D cell layers but also in multicellular tumor spheroids upon irradiation at 740 nm. The complex [Os(4,7‐diphenyl‐1,10‐phenanthroline)$_{2}$(2,2′‐bipyridine)]$^{2+}$ was found to be the most efficient against various cancer cell lines, with high phototoxicity indexes. Experiments on CT26 tumor‐bearing BALB/c mice also indicate that the Os$^{II}$ complexes could significantly reduce tumor growth following 740 nm laser irradiation. The high phototoxicity in the biological window of this structurally simple complex makes it a promising photosensitizer for cancer treatment

Lemierre's syndrome and genetic polymorphisms: a case report

BACKGROUND: Lemierre's syndrome presents a classic clinical picture, the pathophysiology of which remains obscure. Attempts have been made to trace genetic predispositions that modify the host detection of pathogen or the resultant systemic reaction. CASE PRESENTATION: A 17-year old female, with no previous medical history, was admitted to the intensive care unit for septic shock, acute respiratory distress syndrome and Lemierre's syndrome. Her DNA was assayed for single nucleotide polymorphisms previously incriminated in the detection of the pathogen, the inflammatory response and the coagulation cascade. We observed functional variations in her Toll like 5 receptor (TLR 5) gene and two coagulation variations (Tissue Factor (TF) 603 and Plasminogen-Activator-Inhibitor-1 (PAI-1) 4G-4G homozygosity) associated with thrombotic events. CONCLUSION: The innate immune response and the prothrombogenic mutations could explain, at least in part, the symptoms of Lemierre's syndrome. Genomic study of several patients with Lemierre's syndrome may reveal its pathophysiology