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A crystalline hydrogen-bonded framework with permanent porosity, built by rod-like struts and engineered to bear ultra-fast molecular rotors between two triple bonds, offers the possibility of controlling the rotational rates upon CO2 adsorption. CO2 enters the pores from the gas phase and reduces the rotational rates from the extremely fast regime of 107 Hz at 216 K to 105 Hz. The CO2–rotor interaction was evident from the 2H NMR response to the dynamics of the rotors in contact with CO2 in the crystal structure.

The development of solid materials that can be reversibly interconverted by light between forms with different physicochemical properties is of great interest for separation, catalysis, optoelectronics, holography, mechanical actuation and solar energy conversion. Here, we describe a series of shape-persistent azobenzene tetramers that form porous molecular crystals in their E-configuration, the porosity of which can be tuned by changing the peripheral substituents on the molecule. Efficient E -> Z photoisomerization of the azobenzene units takes place in the solid state and converts the crystals into a non-porous amorphous melt phase. Crystallinity and porosity are restored upon Z -> E isomerization promoted by visible light irradiation or heating. We demonstrate that the photoisomerization enables reversible on/off switching of optical properties such as birefringence as well as the capture of CO2 from the gas phase. The linear design, structural versatility and synthetic accessibility make this new family of materials potentially interesting for technological applications.

This study reports the structure-activity relationship of a series of 8-hydroxoquinoline derivatives (8-HQs) and focuses on the cytotoxic activity of 5-Cl-7-I-8-HQ (clioquinol, CQ) copper complex (Cu(CQ)). 8-HQs alone cause a dose-dependent loss of viability of the human tumor HeLa and PC3 cells, but the coadministration of copper increases the ligands effects, with extensive cell death occurring in both cell lines. Cytotoxic doses of Cu(CQ) promote intracellular copper accumulation and massive endoplasmic reticulum vacuolization that precede a nonapoptotic (paraptotic) cell death. The cytotoxic effect of Cu(CQ) is reproduced in normal human endothelial cells (HUVEC) at concentrations double those effective in tumor cells, pointing to a potential therapeutic window for Cu(CQ). Finally, the results show that the paraptotic cell death induced by Cu(CQ) does not require nor involve caspases, giving an indication for the current clinical assessment of clioquinol as an antineoplastic agent. © 2012 American Chemical Society.

A crystalline hydrogen-bonded framework with permanent porosity, built by rod-like struts and engineered to bear ultra-fast molecular rotors between two triple bonds, offers the possibility of controlling the rotational rates upon CO

El objetivo del presente estudio fue estudiar la epidemiología y efecto productivo de los nematodes gastrointestinales (NGI) sobre las terneras de destete en la región del pastizal serrano del NOA durante los períodos A (julio de 2013 a junio de 2014) y B (abril de 2014 a noviembre de 2015). En cada período se formaron tres grupos de terneras: GTM con tratamiento mensual (moxidectin: 200 mcg/kg), GTL con el tratamiento del establecimiento al inicio del ensayo (albendazole: 10 mg/kg en A y doramectina: 200 mcg/kg en B) y GST sin tratamiento antihelmíntico. Se realizó conteo de huevos por gramo de heces (hpg) y coprocultivos para diferenciación de géneros y se registró la ganancia de peso vivo (GPV). Las diferencias entre grupos de estos parámetros se compararon por mínimos cuadrados. En las terneras de destete los hpg más elevados se observaron a mediados de invierno, descendieron en primavera, para elevarse nuevamente a fines de verano en las terneras de sobreaño. Los géneros Haemonchus, Cooperia y Ostertagia predominaron dentro de un plano de infestación moderada, aunque Oesophagostomum y Trichostrongylus estuvieron presentes a lo largo de las observaciones. Durante el período A se observaron diferencias significativas (p

Compositi nanostrutturati sono stati ottenuti dalla polimerizzazione radicalica dell’acrilonitrile, stechiometrico e in eccesso, all’interno della matrice porosa del PAF1. Le analisi spettroscopiche e termiche hanno rilevato una presenza massiva di poliacrilonitrile all’interno della matrice porosa e hanno evidenziato un’intima relazione tra le nanofasi. Trattamenti termici e successive analisi spettroscopiche hanno evidenziato come la matrice polimerica possa essere utilizzata come supporto per la trasformazione termica del PAN.

This paper reviews the main macroeconomic trends and the debate on policy priorities in Italy since the advent of EMU. It argues that, in the decade up to the outbreak of the global crisis (1998-2007), in Italy the reform process came to a virtual standstill and fiscal policy was inconsistent with the commitments taken on at the European level. The paper suggests that the lack of resolute policy reactions to the institutional dysfunctions and structural weaknesses was due to the fragmentation of the political constituency, while a variety of favourable contingent factors masked the difficulties of the productive system. Had Italy been better positioned in terms of public finances and structural features in 2007, some of the adverse effects of the global and sovereign crises would have been avoided. JEL Classification: E6, H3, K0, N1 Keywords: EMU, fiscal policy, macroeconomic imbalances, global crisis, PSL Quarterly Review, V. 67, N. 268 (2014)

Objective: To test the a priori hypothesis that longer duration of ruptured membranes is associated with increased risk of vertical transmission of HIV. Design: The relationship between duration of ruptured membranes and vertical transmission of HIV was evaluated in an individual patient data meta-analysis. Methods: Eligible studies were prospective cohort studies including at least 100 mother-child pairs, from regions where HIV-infected women are counselled not to breastfeed. Analyses were restricted to vaginal deliveries and non-elective Cesarean sections; elective Cesarean section deliveries (those performed before onset of labour and before rupture of membranes) were excluded. Results: The primary analysis included 4721 deliveries with duration of ruptured membranes ≤ 24 h. After adjusting for other factors known to be associated with vertical transmission using logistic regression analysis to assess the strength of the relationship, the risk of vertical HIV transmission increased approximately 2% with an increase of 1 h in the duration of ruptured membranes [adjusted odds ratio, 1.02; 95% confidence interval, 1.01-1.04; for each 1 h increment]. There were no significant interactions of duration of ruptured membranes with study cohort or with any of the covariates, except maternal AIDS. Among women diagnosed with AIDS, the estimated probability of transmission increased from 8% to 31% with duration of ruptured membranes of 2 h and 24 h respectively (P < 0.01). Conclusions: These results support the importance of duration of ruptured membranes as a risk factor for vertical transmission of HIV and suggest that a diagnosis of AIDS in the mother at the time of delivery may potentiate the effect of duration of ruptured membranes. © 2001 Lippincott Williams & Wilkins.

We present here two ligand classes based on a bis(pyrazolyl)methane scaffold functionalized with a rigid (-Ph-S-Ph) or flexible (-CH(2)-S-Ph) thioether function: L(R)PhS (R = H, Me) and L(R)CH(2)S (R = H, Me, iPr). The X-ray molecular structures of Ag(I) and Cu(I) binary complexes with L(R)PhS or L(R)CH(2)S using different types of counterions (BF(4)(-), PF(6)(-), and CF(3)SO(3)(-)) are reported. In these complexes, the ligands are N(2) bound on a metal center and bridge on a second metal with the thioether group. In contrast, when using triphenylphosphine (PPh(3)) as an ancillary ligand, mononuclear ternary complexes [M(L)PPh(3)](+) (M = Cu(I), Ag(I); L = L(R)PhS, L(R)CH(2)S) are formed. In these complexes, the more flexible ligand type, L(R)CH(2)S, is able to provide the N(2)S chelation, whereas the more rigid L(R)PhS ligand class is capable of chelating only N(2) because the thioether function preorganized, as it did in the coordination polymers, to point away from the metal center. Rigid potential-energy surface scans were performed by means of density functional theory (DFT) calculations (B3LYP/6-31+G) on the two representative ligands, L(H)PhS and L(H)CH(2)S. The surface scans proved that the thioether function is preferably oriented on the opposite side of the bispyrazole N(2) chelate system. These results confirm that both ligand classes are suitable components for the construction of coordination polymers. Nevertheless, the methylene group that acts as a spacer in L(H)CH(2)S imparts an inherent flexibility to this ligand class so that the conformation responsible for the N(2)S chelation is energetically accessible.

The heteroscorpionate N(2)S(2) donor ligand bis(3,5-tertbutylpyrazol-1-yl)dithioacetate (L) was prepared as a Li(+) trinuclear complex, which co-crystallizes with tetrahydrofuran (THF) solvent molecules: [Li(L)](3) x (2.25)THF. When [Li(L)](3) was reacted with AgBF(4) or [Cu(CH(3)CN)(4)]BF(4), the oligonuclear species [Ag(L)](3) and [Cu(5)(L)(4)]BF(4) were isolated and structurally characterized. The Ag(+) complex presents an irregular trinuclear structure in which three AgL moieties define a central trigonal site that may potentially host a fourth metal ion. The Cu(+) complex exhibits a highly symmetric pentanuclear structure in which four equivalent CuL moieties shape an internal tetrahedral site occupied by an additional Cu(+) ion. According to electrospray-mass spectrometry (ESI-MS) and (1)H diffusion NMR spectroscopy, the Ag(+) and Cu(+) complexes maintain oligonuclear structures in solution. In particular, the Cu(+) pentanuclear complex, once dissolved, rapidly equilibrates with the tetranuclear species [Cu(4)(L)(3)](+). This is confirmed by the presence of two sets of NMR signals, which demonstrated a change in ratio at different complex concentrations effected by a NMR dilution titration. Variable temperature NMR experiments (210-303 K) defined the activation parameters associated with the fluxional behavior of [Cu(5)(L)(4)]BF(4) and [Cu(4)(L)(3)](+), and these results are consistent with intramolecular rearrangements in both species (DeltaS(double dagger)0).

La fasciolosis es uno de los mayores problemas sanitarios de origen parasitario en los rumiantes del Noroeste argentino. Varias de las técnicas diagnósticas coprológicas para Fasciola hepatica adolecen de poca sensibilidad, de ser muy complejas e insumir mucho tiempo. Esta comunicación describe y evalúa dos métodos coprológicos alternativos para el diagnóstico de F. hepatica mediante su comparación con otras técnicas previamente descriptas. El primero de ellos, denominado de sedimentación y tinción con Azul de Metileno (SAM) es de fácil lectura y al no emplear sales saturadas, está libre del inconveniente de deformar los huevos de F. hepatica en forma prematura. Este método reduce los sedimentos a través de sucesivos tamizados y contrasta claramente los huevos no teñidos (de color amarillento) con el resto de los detritos teñidos de azul. El segundo método, una variante del SAM, llamadode “recupero del Mc Master” (RMM), sigue los pasos del primero pero partiendo de material recuperado del sobrante del diagnóstico del recuento de huevos por gramo. El recupero tiene la ventaja de permitir un diagnóstico coprológico completo cuando las heces recibidas son de escaso volumen, hecho habitual en pequeños rumiantes. El resultado de ambos métodos es cuantitativo y hace referencia al número de huevos de F. hepatica por gramo de heces. Para evaluarlos se los comparó con tres técnicas de sedimentación como la de Dennis et al. (1954) descripta por el CICV del INTA Castelar (CICV), la misma técnica modificada por el Laboratorio de Servicio de Lucha Sanitaria (SELSA) y la técnica utilizada por el Laboratorio de Parasitología de la EEA-Bariloche. Se procesaron muestras individuales de heces provenientes de 29 animales (bovinos, ovinos y caprinos) de rebaños infestados con F. hepatica. Los resultados se analizaron mediante la prueba no paramétrica de Kruskal Wallis. Con las técnicas propuestas el promedio de huevos de F. hepática por gramo (Fpg) contados con SAM (Fpg= 30,06) y RMM (Fpg= 27,59) fueron mayores (p

Weak interactions such as π-π, CH-π, H bonds and VdW forces, play a key role in the rational design of new fascinating supramolecular materials. In effect these interactions are able to drive the self-assembly of simple building blocks to create well defined molecular polyhedra. These materials have attracted much attention not only for their infinite range of application but also thanks to their very interesting supramolecular architectures. Here we present how 72 H-bonds guide the assembly of two kinds of hexagonal molecular tiles in a quasi-truncated octahedron q-TO (which corresponds to one of the 13 Archimedean solids)1 and how different counterions (BF4-, PF6- or NO3-, CF3SO3-) can largely modulate the structure of hexameric toroidal supramolecules h-SP which, at higher hierarchical level, can assembly in sphere2. Both q-TO and h-SP crystallize in high symmetric cubic space groups and both present a void volume inside the macrostructure: q-TO have a 2200Å3 of free total volume and it exhibits the remarkably ability of encapsulate a large assortment of molecular species as solvent molecules and organic guests; h-SP shows a permanent porosity with 18000 Å3 of void space and it is a good material for the adsorption of gases such as CO2 or solvent vapors. Porous dipeptide-based crystals held together by hydrogen bonds and showing selective adsorption of CO2 vs N2 are also presented.3

Two polymorphs of 2,7-dihydrobenzo[1,2,3-cd:4,5,6-c′d′] diindazole ("dipyrazoloanthracene"; α and β; DBDI) were isolated and fully characterized by means of structural X-ray powder diffraction methods, thermal, and extended spectroscopic analyses. Different interconversion paths between the two species were evidenced. UV-vis absorption, emission, and excitation spectra were measured, while time-resolved fluorescence studies allowed for the detection of multiple decay processes. In the two species, NH···N hydrogen bonds give rise to manifestly different structures, which, in the rhombohedral β phase, generate permanent porosity. This feature has been further characterized by CO2/N2/CH4 sorption isotherms at different temperatures, highlighting a significant selectivity favoring CO2 trapping. © 2013 American Chemical Society.

The complexation of a preorganized thioether-functionalized bis(pyrazolyl)methane ligand (L) with silver precursors produces supramolecular structures organized at two hierarchical levels: [AgL](6)(X)(6) metal-organic cyclic hexamers and their organization in 3D architectures. The cyclic toroidal hexamers of 22-26 Å external diameter are found to be stable already in solution before self-assembly into the crystalline state. In the 3D lattice, the hexameric building block are arranged in different highly symmetric space groups as a function of a variety of anions (cubic Fd3 with PF(6)(-) or BF(4)(-) and rhombohedral R3 with CF(3)SO(3)(-) or NO(3)(-)) and form cavities with the geometrical shapes of Platonic solids (tetrahedron and octahedron) that can be occupied by a variety of solvent molecules. Upon evacuation, cubic crystals can produce stable frameworks with permanent porosity, which can absorb reversibly several vapors, CO(2) and CH(4).

We report a quantitative structure-activity relationship study of a new class of pyrazole-pyridine copper complexes that establishes a clear correlation between the ability to promote copper accumulation and cytotoxicity. Intracellular metal accumulation is maximized when ligand lipophilicity allows the complex to rapidly cross the membrane. Copper and ligand follow different uptake kinetics and reach different intracellular equilibrium concentrations. These results support a model in which the ligand acts as an ionophore for the metal ion, cycling between intra- and extracellular compartments as dissociated or complexed entities. When treating cancer cells with structurally unrelated disulfiram and pyrazole-pyridine copper complexes, as well as with inorganic copper, the same morphological and molecular changes were reproduced, indicating that copper overload is responsible for the cytotoxic effects. Copper-based treatments drive sensitive cancer cells toward paraptotic cell death, a process hallmarked by endoplasmic reticulum stress and massive vacuolization in the absence of apoptotic features. A lack of caspase activation, as observed in copper-treated dying cells, is a consequence of metal-mediated inhibition of caspase-3. Thus, copper acts simultaneously as an endoplasmic reticulum (ER) stress inducer and a caspase-3 inhibitor, forcing the cell into caspase-independent paraptotic death. The establishment of a mechanism of action common to different copper binding agents provides a rationale for the exploitation of copper toxicity as an anticancer tool. © 2011 American Chemical Society.

Višegodišnji nasadi predstavljaju monokulturu, a suvremeni uzgoj jabuke u odnosu na ostale voćne vrste odlikuju velike promjene tehnologije uzgoja (gusta sadnja s mrežama protiv tuče i sustavima navodnjavanja) i prihvaćanje standarda kvalitete (npr. GlobalGAP, "No Residue" tehnologija). Jabučni savijač (Cydia pomonella) najvažniji je tehnološki štetnik, a njegov prag štetnosti u integriranom programu iznosi samo 0,5 %. U posljednjih 20-ak godina populacija leptira jabučnog savijača u Međimurju znatno se povećala, štetnik je aktivan od zametanja plodova do početka berbe kasnih sorata jabuke, pa je udvostručen broj usmjerenih mjera kemijske i biotehničke zaštite. Tijekom 2014. godine u suvremenom nasadu jabuka na lokalitetu Nedelišće kraj Čakovca proveden pokus primjene mjere konfuzije primjenom ShinEtsu dispenzora tipa Isomate C/OFM, te kombinacije Isomate CTT + Isomate OFM rosso FLEX (slika na naslovnici). Pored konfuzije mužjaka jabučnoga savijača navedeni ShinEtsu dispenzori sadrže i feromone za zbunjivanje breskvina savijača (Cydia molesta). Pokusni dio nasada za primjenu konfuzije pokriven je mrežom protiv tuče, opremljen sustavom za navodnjavanje "kap po kap", zasađena je sorta jabuke Zlatni delišes reinders na slabo bujnoj vegetativnoj podlozi M9. Na polovici površine s pokusom konfuzije dodatno su krajem razvoja prve i druge generacije jabučnoga savijača primijenjeni insekticidi klorantraniliprol i emamektin. Na susjednoj tabli provodio se standardni program zaštite i jabučni savijač suzbijan je šest puta primjenom različitih skupina insekticida (klorpirifos-etil, acetamiprid, klorantraniliprol, metoksifenzoid, tiakloprid i emamektin). Ocjenom zaraze plodova jabuke uzročnikom crvljivosti tijekom lipnja, kolovoza i rujna 2014. nisu očitane razlike na dijelovima na kojima se primjenjuje mjera konfuzije i standardna zaštita insekticidima, te se ova biotehnička mjera zaštite pokazala prihvatljivom u suvremenom nasadu jabuke u sustavu integrirane proizvodnje, na dijelu površine pokrivenom mrežom protiv tuče., The experiment on codling moth (Cydia pomonella) control using mating disruption technique was conducted in apple orchard with hail nets during 2014 growing season. The efficacy of three commercial pheromone preparations: Isomate C/OFM, and combination Isomate C TT + Isomate OFM rosso FLEX, in comparison to standard pesticides program (chlorpyriphos, acetamiprid, chlorantraniliprole, methoxyfenzoide, thiacloprid and emamectin), was evaluated on the base of number of moths caught in pheromone traps and percentage of damaged fruits. Mating disruption method proved to be very effective if applied to parts of the orchard covered by the network against hail. Between dispenser Isomate C/OFM and combination Isomate C TT + Isomate OFM rosso FLEX there was no difference in the efficacy on codling moth (damage on apple fruits were less than 0.5 %). Compared to the standard chemical control, the parts of the experiment using Isomate mating disruption technique is spent less 4-6 applications of insecticides. This method is acceptable for an integrated and organic apple production.

The volume collects the essays presented at the 15th Workshop on Public Finance organised by Banca d'Italia in Perugia from 4 to 6 April 2013. The workshop focused on the link between fiscal policy and macroeconomic imbalances and comprised four sessions. The first session concentrated on the interaction between fiscal policy and macroeconomic imbalances. The second session dealt with the specific problems of the euro area, where insufficient attention to macroeconomic developments contributed to increase fiscal and financial tensions. The third session scrutinized fiscal policy with an eye to the inequalities of emerging economies and resource-rich countries. The last session analysed the experiences so far and the potential prescriptions about the use of fiscal tools in addressing macroeconomic problems.

A series of light- and air-stable silver(I) pyrazolylmethylpyridine complexes [Ag(L(R))]n(BF4)n (L = pyrazolylmethylpyridine; R = H, 1; R = Me, 2; R = i-Pr, 3) and [Ag(L(R))(NO3)]2 (L = pyrazolylmethylpyridine; R = H, 4; R = Me, 5; R = i-Pr, 6) has been synthesized and structurally and spectroscopically characterized. In all of the molecular structures, the pyrazolylmethylpyridine ligands bridge two metal centers, thus giving rise to dinuclear (2, 4, 5, and 6) or polynuclear structures (1 and 3). The role played by the counteranions is also of relevance, because dimeric structures are invariably obtained with NO3(-) (4, 5, and 6), whereas the less-coordinating BF4(-) counteranion affords polymeric structures (1 and 3). Also, through atoms-in-molecules (AIM) analysis of the electron density, an argentophilic Ag···Ag interaction is found in complexes 2 and 4. Thermogravimetric analysis (TGA) shows that the thermolytic properties of the present complexes can be significantly modified by altering the ligand structure and counteranion. These complexes were further investigated as thin silver film precursors by spin-coating solutions, followed by annealing at 310 °C on 52100 steel substrates. The resulting polycrystalline cubic-phase Ag films of ∼55 nm thickness exhibit low levels of extraneous element contamination by X-ray photoelectron spectroscopy (XPS). Atomic force microscopy (AFM) and scanning electron microscopy (SEM) indicate that film growth proceeds primarily via an island growth (Volmer-Weber) mechanism. Complex 4 was also evaluated as a lubricant additive in ball-on-disk tribological tests. The results of the friction evaluation and wear measurements indicate a significant reduction in wear (∼ 88%) at optimized Ag complex concentrations with little change in friction. The enhanced wear performance is attributed to facile shearing of Ag metal in the contact region, resulting from thermolysis of the silver complexes, and is confirmed by energy-dispersive X-ray analysis of the resulting wear scars.

Background To evaluate the relation between elective cesarean section and vertical transmission of human immunodeficiency virus type 1 (HIV-1), we performed a meta-analysis using data on individual patients from 15 prospective cohort studies. Methods North American and European studies of at least 100 mother-child pairs were included in the meta-analysis. Uniform definitions of modes of delivery were used. Elective cesarean sections were defined as those performed before onset of labor and rupture of membranes. Multivariate logistic-regression analysis was used to adjust for other factors known to be associated with vertical transmission. Results The primary analysis included data on 8533 mother-child pairs. After adjustment for receipt of antiretroviral therapy, maternal stage of disease, and infant birth weight, the likelihood of vertical transmission of HIV-1 was decreased by approximately 50 percent with elective cesarean section, as compared with other modes of delivery (adjusted odds ratio, 0.43; 95 percent confidence interval, 0.33 to 0.56). The results were similar when the study population was limited to those with rupture of membranes shortly before delivery. The likelihood of transmission was reduced by approximately 87 percent with both elective cesarean section and receipt of antiretroviral therapy during the prenatal, intrapartum, and neonatal periods, as compared with other modes of delivery and the absence of therapy (adjusted odds ratio, 0.13; 95 percent confidence interval, 0.09 to 0.19). Among mother-child pairs receiving antiretroviral therapy during the prenatal, intrapartum, and neonatal periods, rates of vertical transmission were 2.0 percent among the 196 mothers who underwent elective cesarean section and 7.3 percent among the 1255 mothers with other modes of delivery. Conclusions The results of this meta-analysis suggest that elective cesarean section reduces the risk of transmission of HIV-1 from mother to child independently of the effects of treatment with zidovudine.

A family of bis(pyrazolato)-based metal-organic frameworks (MOFs) was isolated by reacting 1,4-bis(1H-pyrazol-4-ylethynyl)benzene (H2BPEB) with a number of transition metal ions. Special attention was dedicated to their structural features, their thermal and chemical stability, as well as their spectroscopic and adsorption properties. The rod-like ligands, connecting Zn(II), Ni(II) and Fe(III) nodes, fabricate 3-D networks containing 1-D pervious channels. The combination of thermal analysis and variable-temperature XRPD demonstrated the remarkable thermal robustness of the three materials, which are stable in air up to at least 410 °C, and showed their structural response to increasing temperature. Specific experiments permitted us to test the chemical stability of the three species toward water as well as moderately acidic and basic solutions, the Ni(II) derivative being stable and hydrophobic in all the conditions assayed. The electronic transitions of both the ligand and the MOFs were investigated by solid-state UV-Vis absorption as well as by steady-state and time-resolved fluorescence analysis, which showed that the high fluorescence of the linker is perturbed in the three MOFs, suggesting high sensitivity to environmental changes. N2 adsorption measurements at 77 K allowed to estimate promising Langmuir specific surface areas, peaking at 2378 m2 g−1 in the case of the Ni(II) derivative. The best CO2 and CH4 uptake performances were achieved with the Fe(III)-based MOF. Indeed, adsorption experiments with CO2 revealed that a considerable amount, up to 40% wt, is adsorbed by the Fe(III) derivative under the mild conditions of 298 K and 10 bar.