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The reaction of trans-[RhCl(CO)(dppm)]2 with P4 carried out at room temperature showed that bimetallic cooperation resulted in the cleavage of P4, giving a μ,η2-P2 (μ-κ2:κ2-P2) ligand coordinated to the two metal centres. The new complex cis-[Rh2(CO)2(μ-dppm)2(μ,η2-P2)] has been fully characterised in solution by NMR spectroscopy and in the solid state by single-crystal X-ray diffraction. The Rh-Rh distance of 2.723(18) Å is consistent with the presence of a metal-metal single bond, which was supported by theoretical analysis showing that the HOMO of the complex has metal-metal bond character. A literature survey revealed that, in most cases, the P2 unit acts as a P24- ligand, and also in the case at hand the diphosphenyl ligand behaves as an eight-electron donor with all the π* combinations occupied and donates into four empty metal combinations. [ABSTRACT FROM AUTHOR]

The reaction of R2P-P(SiMe3)Li (R = tBu, iPr) with the diimido molybdenum complex [(ArN)2MoCl2 ·dme] (Ar = 2,6- iPr2C6H3; dme = 1,2-dimethoxyethane) yielded the side-on-coordinated phosphanylphosphinidene anionic complexes [(2,6- iPr2C6H3N)2Mo(Cl)(η2-P=PR2)]- ( 7Mo, 8Mo). The thermal decomposition of [(2,6- iPr2C6H3N)2M(Cl)(η2-P=PR2)]- [M = Mo ( 7Mo), W ( 8W)] to [(2,6- iPr2C6H3N)2M(Cl)(1,2-η- tBu2P=P-P tBu2)] [M = Mo ( 3Mo), W ( 3W)] was investigated by 31P{1H} NMR spectroscopy. The reactions of [(ArN)2MCl2 ·dme] (Ar = 2,6- iPr2C6H3; M = Mo, W) with tBu2P-P(Li)-P tBu2 gave molybdenum and tungsten complexes [(2,6- iPr2C6H3N)2M(Cl)(1,2-η- tBu2P=P-P tBu2)] ( 3Mo, 3W) bearing an unusual triphosphorus ligand. The solid-state structures of [(2,6- iPr2C6H3N)2Mo(Cl)(η2-P=P tBu2)]- ( 7Mo), [(2,6- iPr2C6H3N)2Mo(Cl)(η2-P=P iPr2)]- ( 8Mo), [(2,6- iPr2C6H3N)2Mo(Cl)(1,2-η- tBu2P=P-P tBu2)] ( 3Mo) and [(2,6- iPr2C6H3N)2W(Cl)(1,2-η- tBu2P=P-P tBu2)] ( 3W) were established by single-crystal X-ray diffraction analysis. [ABSTRACT FROM AUTHOR]

The selective of the polyphosphorus moiety Ph2PCH2PPh2 PPPP present as a tetrahapto-ligand in complex [Ir(dppm)(Ph2PCH2PPh2 PPPP)]+ ( 1, dppm=Ph2PCH2PPh2) was obtained by reaction of 1 with water under basic conditions at room temperature. The formation of the new triphosphaallyl moiety η3-P3{P(O)H} was determined in solution by NMR spectroscopy, and confirmed in the solid state by a single-crystal X-ray structure of the stable product [Ir(κ2-dppm)(κ1-dppm)(η3-P3{P(O)H})] ( 2). In solution, 2 has a fluxional behavior attributable to the four P atoms belonging to the tetraphosphorus moiety in 1 and exhibits a chemical exchange process involving the two PPh2 moieties of the same bidentate ligand, as determined by 1D and 2D NMR spectroscopy experiments carried out at variable temperature. The mechanism of the reaction was investigated at the DFT level, which suggested a selective attack of an in-situ generated OH− anion on one of the non-coordinated phosphorus atoms of the P4 moiety. The reaction then evolves through an acid-assisted , which leads to the final compound 2. Bonding analysis pointed out that the new unsubstituted P3-unit in the η3-P3{P(O)H} moiety behaves as a triphosphallyl ligand. [ABSTRACT FROM AUTHOR]

The selective of the polyphosphorus moiety Ph2PCH2PPh2 PPPP present as a tetrahapto-ligand in complex [Ir(dppm)(Ph2PCH2PPh2 PPPP)]+ ( 1, dppm=Ph2PCH2PPh2) was obtained by reaction of 1 with water under basic conditions at room temperature. The formation of the new triphosphaallyl moiety η3-P3{P(O)H} was determined in solution by NMR spectroscopy, and confirmed in the solid state by a single-crystal X-ray structure of the stable product [Ir(κ2-dppm)(κ1-dppm)(η3-P3{P(O)H})] ( 2). In solution, 2 has a fluxional behavior attributable to the four P atoms belonging to the tetraphosphorus moiety in 1 and exhibits a chemical exchange process involving the two PPh2 moieties of the same bidentate ligand, as determined by 1D and 2D NMR spectroscopy experiments carried out at variable temperature. The mechanism of the reaction was investigated at the DFT level, which suggested a selective attack of an in-situ generated OH− anion on one of the non-coordinated phosphorus atoms of the P4 moiety. The reaction then evolves through an acid-assisted , which leads to the final compound 2. Bonding analysis pointed out that the new unsubstituted P3-unit in the η3-P3{P(O)H} moiety behaves as a triphosphallyl ligand. [ABSTRACT FROM AUTHOR]

The terminal rhenium(I) phosphaethynolate complex [Re(PCO)(CO)2(triphos)] has been prepared in a salt metathesis reaction from Na(OCP) and [Re(OTf)(CO)2(triphos)]. The analogous isocyanato complex [Re(NCO)(CO)2(triphos)] has been likewise prepared for comparison. The structure of both complexes was elucidated by X-ray diffraction studies. While the isocyanato complex is linear, the phosphaethynolate complex is strongly bent around the pnictogen center. Computations including natural bond orbital (NBO) theory, natural resonance theory (NRT), and natural population analysis (NPA) indicate that the isocyanato complex can be viewed as a classic Werner-type complex, that is, with an electrostatic interaction between the ReI and the NCO group. The phosphaethynolate complex [Re(PCO)(CO)2(triphos)] is best described as a metallaphosphaketene with a ReI-phosphorus bond of highly covalent character. [ABSTRACT FROM AUTHOR]

Dynamic processes involving the P4cage coordinated to transition metal fragments were observed for the mononuclear complex trans-[Ru(dppm)2(H)(η1-P4)]BF4and for the bimetallic derivative trans-[Ru(dppm)2(H)(μ ,η1:2-P4){Pt(PPh3)2}]BF4as demonstrated by NMR experiments and DFT calculations. [ABSTRACT FROM AUTHOR]

The article focuses on the activation of white phosphorus (P4) through late-transition metal complexes. According to the authors, the importance of studying the coordination chemistry of elemental phosphorus through late and early metal complexes are based on the need for replacing current technology for manufacturing organophosphorus derivatives. This reaction is based on the chlorination of white phosphorus followed by the reaction of PCl3 with an organic molecule.

New 2D black phosphorus (bP)–phthalocyanine (Pc) nanohybrids have been synthesized by liquid phase exfoliation of black phosphorus crystals in the presence of two organic dyes: phthalocyanine (Pc) and manganese phthalocyanine (MnPc). The key role of the metal cation in the interfacial interaction between the organic dye and bP nanosheets was demonstrated by X‐ray absorption spectroscopy and associated with an electron transfer between the metal cation Mn2+ and bP nanosheets, which resembles a coordinative chemical bond. On the other hand, the interaction between bP nanosheets and pure phthalocyanine is governed by van der Waals forces. The fluorescence of both hybrids is significantly reduced indicating effective separation of the photoinduced charge, implying the formation of a heterojunction between the organic molecules and the bP nanosheets. These findings provide important insights into the interfacial interactions in bP‐Pc nanohybrids that are relevant for application in 2D organic/inorganic devices. [ABSTRACT FROM AUTHOR]

tert-Butyl-substituted diphospha[2]ferrocenophane was used as a stereochemically confined diphosphane to investigate the addition of various dichalcoganes (R2Ch2; Ch = S, Se, Te and R = Me, Ph). Bischalcogenophosphinous acid esters bearing four soft donor sides were obtained as a mixture of rac and meso diastereomers and characterized by means of multinuclear NMR and X-ray analysis. The coordination chemistry of multidentate ligand 3b was explored toward d10 coinage metal centers (Cu(I), Ag(I), and Au(I)), yielding various bimetallic complexes. [ABSTRACT FROM AUTHOR]

Resistivity measurements of a black phosphorus (bP) field‐effect transistor 16 nm thick in parallel magnetic fields up to 45 T are reported as a function of the angle between the in‐plane field and the source–drain (S–D) axis of the device. The crystallographic directions of the bP crystal are determined by Raman spectroscopy, with the zigzag axis found to be within 5° of the S–D axis and the armchair axis in the orthogonal planar direction. A transverse magnetoresistance (TMR) as well as a classically forbidden longitudinal magnetoresistance (LMR) are observed. Both are found to be strongly anisotropic and nonmonotonic with increasing in‐plane field. Surprisingly, the relative magnitude (in %) of the positive LMR is larger than the TMR above ≈32 T. Considering the known anisotropy of bP whose zigzag and armchair effective masses differ by a factor of ≈7, the experiment strongly suggests this LMR to be a consequence of the anisotropic Fermi surface of bP. [ABSTRACT FROM AUTHOR]

Nowadays, prostate cancer is the most widespread tumour in worldwide male population. Actually, brachytherapy is the most advanced radiotherapy strategy for the local treatment of prostate cancer. It consists in the placing of radioactive sources closed to the tumour side thus killing cancer cells. However, brachytherapy causes the same adverse effects of external-beam radiotherapy. Therefore, alternative treatment approaches are required for enhancing radiotherapy effectiveness and reducing toxic symptoms. Nanostructured exfoliated black phosphorus (2D BP) may represent a strategic tool for local cancer therapy because of its capability to induce singlet oxygen production and act as photosensitizer. Hence, we investigated 2D BP in vitro effect on healthy and cancer prostate cell behavior. 2D BP was obtained through liquid exfoliation. 2D BP effect on healthy and cancer prostate cell behaviors was analyzed by investigating cell viability, oxidative stress and inflammatory marker expression. 2D BP inhibited prostate cancer cell survival, meanwhile promoted healthy prostate cell survival in vitro by modulating oxidative stress and immune response with and without near-infrared light (NIR)-irradiation. Nanostructured 2D BP is able to inhibit in vitro prostate cancer cells survival and preserve healthy prostate cell vitality through the control of oxidative stress and immune response, respectively. [ABSTRACT FROM AUTHOR]

Enhanced laboratory-based surveillance of invasive meningococcal disease (IMD) in Italy was only assessed indirectly by numerically comparing surveillance data cases with hospital discharge records (HDR). In this study, we evaluated the completeness, timeliness and sensitivity of the IMD surveillance in Italy from 2015 to 2018. Completeness and timeliness were described at the national and subnational level. A capture-recapture analysis was conducted to evaluate the sensitivity and positive predictive value (PPV) using HDR as the external source with a combination of deterministic and probabilistic approaches. The characteristics of the unmatched vs. matched cases were compared using multivariable Poisson modeling. Overall, the completeness of data improved, except for specific variables. Timeliness of notifications also improved to a median of 4 days from onset to reporting. For the years 2015–2017, the sensitivity of the surveillance was estimated at 71.4% and the PPV at 77.5%, changing to 80.6% and 66.9% respectively after removing cases with a secondary meningitis diagnosis. We noted substantial sub-national differences. In 2018 sensitivity was 66.5% (135/203) and the PPV was 79.4% (135/170). The adjusted relative risk of being unmatched in 2015–2017 was higher in cases that were ≥60 years, had missing information or symptom onset in December. The IMD surveillance system overall performs well with completeness and timeliness improving in time. Specific challenges identified for individual variables should guide further improvement. Notwithstanding limitations posed by the comparison database, sensitivity and PPV are promising. The study highlights that promoting etiological ascertainment in people ≥60 years and addressing sub-national challenges are the main current challenges to address. [ABSTRACT FROM AUTHOR]

Nanostructured In 2 O 3 was grown on TiO 2 NPs by thermal treatment of the solids mixture of TiO 2 with the parent In(OH) 3. The effect of calcination temperature in the range between 400 °C and 700 °C was investigated and peculiar changes both in the structure and in the catalytic activity of the TiO 2 /In 2 O 3 heterostructure were revealed. It was found out that T = 600 °C is the best operating temperature for hydrogen production and in combination with 3.5 wt% In 2 O 3 the H 2 production from water reached the value of 3.5 mmol/h.g irradiating in the UV–Vis region. Once 5.0 wt% Cu 2 O nanoparticles were loaded on TiO 2 /In 2 O 3 , the photocatalytic activity boosted to 9.6 mmol/h.g of H 2 , overcoming the hydrogen production of pristine TiO 2 by a factor of 48. This result can be attributed to the formation of a highly efficient heterojunction that assures a synergistic cooperation among the three semiconductors yielding an improved charge separation and faster charge transport, as evidenced by Mott-Schottky, PL and EIS measures. [Display omitted] • Thermal annealing of the mixture TiO 2 /In(OH) 3 was studied at different temperatures. • Improved HER activity for TiO 2 /In 2 O 3 annealed at T = 600 °C was observed. • A double carrier density and a reduced resistivity were measured for calcined TiO 2 /In 2 O 3. • Integration of Cu 2 O boosted the photocatalytic activity 48-folds respect to TiO 2. [ABSTRACT FROM AUTHOR]

Photocatalysts which are stable to photocorrosion and noble metal‐free, are highly desirable to achieve a light‐driven hydrogen production which satisfies the criteria of low production cost and environmental sustainability. Herein, a new heterostructure TiO2/BP/CoP has been developed, in which the BP nanosheets interact strongly with TiO2 and CoP, speeding up the transfer of photogenerated electrons and thus increasing H2 production. Once BP is added to TiO2 (P25) as only 1 % wt., the H2 evolution rate increases up to 4 times reaching a value of 830 μmol/g ⋅ h under UV‐Vis light irradiation. By integrating CoP nanoparticles as a cocatalyst up to 2 % wt., H2 production is further promoted to 7400 μmol/g ⋅ h, 37 times higher than pristine TiO2. Photoluminescence and electrochemical impedance measurements show that this heterostructure achieves a much more efficient charge separation and reduction of the internal resistance in comparison to pristine TiO2. Combining these data with UV‐Vis diffuse reflectance and Mott‐Schottky, a plausible mechanism was proposed. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented regarding bacterial pneumonia that is identified to be the leading cause of influenza cases.

Layered black phosphorus (BP) is endowed with peculiar chemico‐physical properties that make it a highly promising candidate in the field of electronics. Nevertheless, as other 2D materials with atomic scale thickness, it suffers from easy degradation under ambient conditions. Herein, it is shown that the functionalization of BP with preformed and in situ grown Ni NPs, affects the electronic properties of the material. In particular, Ni functionalization performed in situ leads to a narrowing of the average BP band gap from 1.15 to 0.95 eV and to a marked shift in the conduction band maximum from −0.33 V to −0.07 V, which, in turn, improve the ambient stability. Structural studies carried out by XAS can well distinguish the two nanohybrids and reveal that once Ni NPs are grown on BP nanosheets, a Ni‐P coordinative bond is formed, featuring a short Ni‐P distance of 2.27 Å, which is not observed when preformed Ni NPs are immobilized on BP. Comparing the XANES and EXAFS spectra of fresh and aged samples of both nanohybrids, suggests that the interaction between Ni and P atoms results in a stabilization effect exerted via a dual electronic and redox mechanism, that infers a much superior ambient stability to BP, even if the surface functionalization is far to achieve a full coverage. [ABSTRACT FROM AUTHOR]

Binary ruthenium‐phosphorus nanoparticles (NPs) with different Ru/P ratio were prepared in mild conditions using white phosphorus (P4) as phosphorus source. Accurate study of both their morphology and structure at the atomic level by TEM and HAADF‐STEM, respectively, showed that Ru2P and RuP have a narrow size distribution (ca. 3.3 nm) and are lacking an ordered ruthenium phosphide lattice. 31P Solid State NMR highlighted the existence of three different phosphorus species consistently with the lack of a metal phosphide lattice and finally XPS revealed that the true nature of these nanoparticles can be better described as a ruthenium‐phosphorus alloy. As a benchmark test, the selective hydrogenation of nitroarenes to primary aromatic amines was studied and evidenced how the P‐alloying imparts a surface modification resulting in a higher catalytic activity and excellent chemoselectivity of Ru2P in comparison to Ru(0) and RuP. [ABSTRACT FROM AUTHOR]

Black phosphorus nanosheets (2D BP) are emerging as very promising, highly selective chemotherapeutic agents due to their fast degradation in the intracellular matrix of cancer cells. Here, optical diffraction tomography (ODT) and Raman spectroscopy were exploited as a powerful label-free approach to achieve integrated insights into the processes accompanying the administration of exfoliated 2D BP flakes in human prostatic adenocarcinoma and normal human prostate epithelial cells. Our ODT experiments provided unambiguous visualization of the 2D BP internalization in cancer cells and the morphological modifications of those cells in the apoptotic phase. The cellular internalization and damaging occurred, respectively, 18 h and 36–48 h after the 2D BP administration. Changes in the chemical properties of the internalized 2D BP flakes were monitored by Raman spectroscopy. Interestingly, a fast oxidation process of the 2D BP flakes was activated in the intracellular matrix of the cancer cells after 24 h of incubation. This was in sharp contrast to the low 2D BP uptake and minimal chemical changes observed in the normal cells. Along with the understanding of the 2D BP fate in the cancer cells, the proposed label-free morpho-molecular approach offers a powerful, rapid tool to study the pharmacokinetic properties of engineered nanomaterials in preclinical research. [ABSTRACT FROM AUTHOR]

Abstract: The introduction of Haemophilus influenzae type b (Hib) conjugate vaccines has greatly reduced the incidence of invasive Hib disease. However, concern exists about the possible emergence of “strain replacement”. We report the epidemiology and characterization of isolates from invasive H. influenzae disease in Italy through 2007–2009, 10 years after Hib vaccination was introduced. Invasive H. influenzae disease cases were detected through the National Surveillance of Invasive Bacterial Disease. Seventy-eight H. influenzae strains were serotyped and tested for antimicrobial susceptibility. Genetic basis of resistance to β-lactams was investigated. The annual incidence of invasive H. influenzae infection was 0.06/100,000 in 2007, 0.08/100,000 in 2008 and 0.09/100,000 in 2009 in all age groups. A slight increase in disease incidence has been observed in adults ≥65 years since 2007. Nonencapsulated (ncHi) predominated among H. influenzae isolates from all age groups: 61.5%, 76.0%, and 75.0% for <5, 5–64 and ≥65 years, respectively. Although ncHi mainly caused bacteremia, meningitis due to ncHi increased in comparison with previous data (38.6% in 2007–2009 vs. 26.2% 1997–2002). Prevalence of encapsulated non-Hib strains grew significantly (4.1% in 1997–2002 vs.16.7% in 2007–2009; p <0.001), although they remained rare. Resistance to ampicillin mediated by β-lactamase declined, but that due to altered penicillin-binding protein 3 increased. In conclusion, routine use of Hib vaccines produced both a drastic decrease in the number of invasive H. influenzae cases and epidemiological changes in disease. Overall, pediatric H. influenzae disease has become less common whereas there has been a slight increase of disease in the elderly. A marked change in the predominant serotype from Hib to ncHi has occurred. Changes in the H. influenzae population moderately affected antibiotic resistance trends. [Copyright &y& Elsevier]

In 2017, a chikungunya outbreak in central Italy later evolved into a secondary cluster in southern Italy, providing evidence of disease emergence in new areas. Officials have taken action to raise awareness among clinicians and the general population, increase timely case detection, reduce mosquito breeding sites, and promote mosquito bite prevention. [ABSTRACT FROM AUTHOR]

• Strategies for migrants immunization are in line with WHO and ECDC in the six countries. • Individual data on immunized migrants are available at national level in two countries. • Procedures to keep track of data on migrants immunization across countries are lacking. Over the last three years an unprecedented flow of migrants arrived in Europe. There is evidence that vaccine preventable diseases have caused outbreaks in migrant holding centres. These outbreaks can be favored by a combination of factors including low immunization coverage, bad conditions that migrants face during their exhausting journey and overcrowding within holding facilities. In 2017, we conducted an online survey in Croatia, Greece, Italy, Malta, Portugal and Slovenia to explore the national immunization strategies targeting irregular migrants, refugees and asylum seekers. All countries stated that a national regulation supporting vaccination offer to migrants is available. Croatia, Italy, Portugal and Slovenia offer to migrant children and adolescents all vaccinations included in the National Immunization Plan; Greece and Malta offer only certain vaccinations, including those against diphtheria-tetanus-pertussis, poliomyelitis and measles-mumps-rubella. Croatia, Italy, Malta and Portugal also extend the vaccination offer to adults. All countries deliver vaccinations in holding centres and/or community health services, no one delivers vaccinations at entry site. Operating procedures that guarantee the migrants' access to vaccination at the community level are available only in Portugal. Data on administered vaccines is available at the national level in four countries: individual data in Malta and Croatia, aggregated data in Greece and Portugal. Data on vaccination uptake among migrants is available at national level only in Malta. Concluding, although diversified, strategies for migrant vaccination are in place in all the surveyed countries and generally in line with WHO and ECDC indications. Development of procedures to keep track of migrants' immunization data across countries, development of strategies to facilitate and monitor migrants' access to vaccinations at the community level and collection of data on vaccination uptake among migrants should be promoted to meet existing gaps. [ABSTRACT FROM AUTHOR]

Phosphorene, the 2D material derived from black phosphorus, has recently attracted a lot of interest for its properties, suitable for applications in materials science. The physical features and the prominent chemical reactivity on its surface render this nanolayered substrate particularly promising for electrical and optoelectronic applications. In addition, being a new potential ligand for metals, it opens the way for a new role of the inorganic chemistry in the 2D world, with special reference to the field of catalysis. The aim of this review is to summarize the state of the art in this subject and to present our most recent results in the preparation, functionalization, and use of phosphorene and its decorated derivatives. We discuss several key points, which are currently under investigation: the synthesis, the characterization by theoretical calculations, the high pressure behavior of black phosphorus, as well as its decoration with nanoparticles and encapsulation in polymers. Finally, device fabrication and electrical transport measurements are overviewed on the basis of recent literature and the new results collected in our laboratories. Black phosphorus and its exfoliated product, phosphorene, are rising stars in the 2D materials field. The role of inorganic chemistry is presented, the black phosphorus surface being a potential anchoring point for metal fragments. The applications of phosphorene and its functionalized derivatives in devices are also reported. [ABSTRACT FROM AUTHOR]

Abstract: To assess in Italy the pre-pandemic susceptibility of the general population to the 2009 A/H1N1v influenza virus, 587 serum samples collected in 2004 were analyzed using haemagglutination-inhibition (HI), single-radial-haemolysis (SRH) and microneutralisation (MN) assays. Serum samples were stratified by age group, gender, and geographic area. Overall, using HI assay, the proportion of subjects showing antibodies cross-reacting with 2009 A/H1N1v virus at seroprotection level (≥1:40) was estimated to be 6.7%, 12.4%, and 22.4% in individuals born between 2004 and 1949, 1948 and 1939, 1938 and 1909, respectively. With a HI antibody titre of ≥1:10, in the same birth cohort, the seroprotection levels were 13.5%, 19.2%, and 58.2%, respectively. The results suggest that the Italian population was not fully naïf to the current pandemic virus and that the possible previous exposure and immune response increases with age. [Copyright &y& Elsevier]