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1.
Euro Surveill ; 27(29)2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35866436

RESUMO

In spring 2022, Europe faced an unprecedented heatwave, increasing the risk of West Nile virus (WNV) outbreaks. As early as 7 June 2022, WNV was detected in Culex mosquitoes in northern Italy, and - in the following days - in two blood donors, a patient with encephalitis, wild birds and additional mosquito pools. Genome sequencing demonstrated co-circulation of WNV lineage 2 and a newly introduced WNV lineage 1, which was discovered in the region in 2021.


Assuntos
Culex , Culicidae , Febre do Nilo Ocidental , Vírus do Nilo Ocidental , Animais , Surtos de Doenças , Humanos , Itália/epidemiologia , Estações do Ano , Febre do Nilo Ocidental/diagnóstico , Febre do Nilo Ocidental/epidemiologia , Vírus do Nilo Ocidental/genética
2.
Phys Chem Chem Phys ; 23(15): 9121-9129, 2021 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-33885116

RESUMO

When hydrogen is completely replaced by fluorine, arenes become prone to forming a lone pairπ-hole non-covalent bond with ligands presenting electron rich regions. Such a species is ammonia, which confirms this behavior engaging its lone pair as the electron donor counterpart in the 1 : 1 adducts with hexafluorobenzene and pentafluoropyridine. In this work, the geometrical parameters of the interaction have been unambiguously identified through the detection, by means of Fourier transform microwave spectroscopy, of the rotational spectra of both normal species and their 15NH3 isotopologues. An accurate analysis of the experimental data, including internal dynamics effects, endorsed by quantum chemical calculations, both with topological analysis and energy decomposition method, extended to the hydrogenated arenes and their water complexes, proved the ability of ammonia to create a stronger and more flexible lone pairπ-hole interaction than water. Interestingly, the higher binding energies of the ammonia lone pairπ-hole interactions correspond to larger intermolecular distances.

3.
Phys Chem Chem Phys ; 21(7): 3695-3700, 2019 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-30652707

RESUMO

We report the rotational spectra of three isotopologues of the dimer of chlorofluoromethane, namely CH235ClF-CH235ClF, CH235ClF-CH237ClF and CH237ClF-CH235ClF. The assigned (most stable) conformer is chiral (C1 symmetry) and displays a network of two C-HCl-C and one C-HF-C weak hydrogen bonds, combined with a ClF halogen bond. The hyperfine structures due to the quadrupolar effects of the two non-equivalent 35Cl (or 37Cl) atoms have been fully resolved, leading to an accurate determination of two sets of diagonal and of some mixed quadrupole coupling constants. Information on the rs positions of the two Cl atoms and on the structural parameters of the hydrogen bonds has been obtained. The dissociation energy of the complex has been estimated as 5.9 kJ mol-1.

4.
Chemistry ; 23(46): 11119-11125, 2017 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-28608548

RESUMO

The rotational spectra of two isotopologues of the 1:1 complex formed between acetone and ethanol have been recorded and analyzed by using Fourier-transform microwave spectroscopy. One rotamer was detected, in which ethanol adopts the gauche form. The two subunits are linked by a conventional O-H⋅⋅⋅O and a weak C-H⋅⋅⋅O hydrogen bond, forming a six-membered ring. Each rotational transition is split into five component lines due to the internal rotations of two nonequivalent acetone methyl groups. The V3 barriers to internal rotation of the two CH3 tops of acetone were determined to be 252(4) and 220(1) cm-1 , which are noticeably lower than the value for the monomer (266 cm-1 ).

5.
Foot Ankle Surg ; 22(2): 120-4, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27301732

RESUMO

BACKGROUND: Hypermobility of the first ray, a probable primary cause of hallux valgus, has traditionally been evaluated in the dorsal direction only although the first tarso-metatarsal joint allows movement in a dorso-medial direction. MATERIALS AND METHODS: 600 feet, divided according to the presence or absence of hallux valgus, were evaluated for both dorsal and dorso-medial displacement using a Klaue device. RESULTS: In the control group, the mean first ray displacement was 7.2mm (4.2-11.3) in the dorsal direction (sagittal plane) and 8.3mm (4.0-12.6) in the 45° dorso-medial direction. In the hallux valgus group, the mean first ray mobility was 9.8mm (5.2-14.1) in the dorsal direction compared to a mean of 11.0mm (5.9-16.2) in the 45° dorso-medial direction. CONCLUSION: It is a paradox that hypermobility of the first ray is measured in only a dorsal (vertical) direction whereas a hallux valgus angle and an intermetatarsal angle are only measured in a transverse plane. Furthermore, the weightbearing foot pronates during gait and the first metatarsal is displaced in a dorsomedial direction rather than a pure dorsal direction. It is suggested that measurement hypermobility of the first ray at a 45° dorso-medial direction is more appropriate.


Assuntos
Hallux Valgus/fisiopatologia , Instabilidade Articular/fisiopatologia , Articulação Metatarsofalângica/fisiopatologia , Amplitude de Movimento Articular/fisiologia , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Hallux Valgus/complicações , Hallux Valgus/cirurgia , Humanos , Instabilidade Articular/complicações , Instabilidade Articular/cirurgia , Masculino , Pessoa de Meia-Idade , Suporte de Carga/fisiologia , Adulto Jovem
6.
Chemistry ; 21(45): 15970-3, 2015 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-26388315

RESUMO

The structural and energetic features of the C-H⋅⋅⋅π interaction and the internal dynamics of the CHF3 group change drastically in going from benzene-CHF3 to indan-CHF3 , according to the analysis of the rotational spectrum of the latter complex generated in a supersonic expansion.

7.
J Phys Chem A ; 119(49): 11813-9, 2015 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-26566085

RESUMO

The rotational spectra of three isotopologues, CH2(35)Cl2···(20)Ne, CH2(35)Cl(37)Cl···(20)Ne, and CH2(35)Cl2···(22)Ne, of the complex dichloromethane-neon have been assigned and measured by molecular beam Fourier transform microwave spectroscopy. The corresponding tunnelling splittings-due to the motion of Ne from above to below the ClCCl plane-have been determined as ΔE0+0- = 6.8900(5), 6.6630(4), and 6.3724(7) MHz, respectively. From these data the barrier to planarity has been obtained, B2 = 68.7 cm(-1). In addition, the structure and the (35)Cl (or (37)Cl) quadrupole coupling constants have been determined.

8.
J Phys Chem A ; 118(24): 4243-8, 2014 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-24848436

RESUMO

The rotational spectrum of trifluoroacetylacetone shows that the molecule exists in an enolic C(s) form and displays the features of internal rotations of the CH3 and CF3 groups, whose barriers to internal rotation were determined to be V3 = 379 and 30.8 cm(-1), respectively. Its internal dynamics appears to be intermediate between those of acetylacetone, where proton tunneling and low-barrier internal rotation of the two methyl groups make the spectrum quite complex, and hexafluoroacetylacetone, a perfectly "rigid" molecule on the time scale of microwave spectroscopy.

9.
J Phys Chem A ; 118(45): 10738-41, 2014 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-25329531

RESUMO

The rotational spectrum of the 1:1 complex between formic acid and formaldehyde shows that the two units are linked together through a "classical" (OH···O) and a weak (CH···O) hydrogen bond. The molecular system appears quite rigid, and no effects of the internal motions have been observed in the spectrum.

10.
Analyst ; 138(7): 1959-61, 2013 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-23420390

RESUMO

The rotational signatures of methyl pyruvate as an impurity have been accidentally found and its rotational spectrum was assigned while recording the microwave spectrum of a 98% Sigma-Aldrich sample of methyl (S)-(-)-lactate with the pulsed jet Fourier transform microwave technique.

11.
J Phys Chem A ; 117(44): 11289-92, 2013 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-24138123

RESUMO

The rotational spectrum of pyridine-CF4 has been investigated by molecular beam Fourier transform microwave spectroscopy in a supersonic expansion. The CF4 moiety is located as a cap over the pyridine nitrogen, and the two parts are freely rotating with respect to each other. For this reason, in a first approximation, in the m = 0 state only the pyridine ring is rotating along the a-axis, and the value of rotational constant A' is nearly the same of the constant A of isolated pyridine. The N···CCF4 distance is 3.372(1) Å. The dissociation energy has been estimated, from the centrifugal distortion, to be ca. 10 kJ/mol.

12.
J Phys Chem A ; 117(3): 590-3, 2013 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-23289609

RESUMO

The rotational spectra of five isotopologues (normal and all monosubstituted (13)C species) of methylpyruvate have been measured with the pulsed jet Fourier transform microwave technique. Rotational transitions are split into quintets due to the internal rotations of the two methyl groups. The corresponding barriers to internal rotation have been determined to be V(3)(H(3)C-O) = 4.883(8) kJ mol(-1) and V(3)(H(3)C-C) = 4.657(8) kJ mol(-1), respectively. Information on the skeletal heavy atom structure has been obtained from the 15 available rotational constants.


Assuntos
Micro-Ondas , Piruvatos/química , Teoria Quântica , Análise de Fourier , Rotação
13.
J Phys Chem A ; 117(50): 13712-8, 2013 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-24015670

RESUMO

The free jet millimeter-wave absorption spectrum of 1,3-cyclohexanedione has been investigated in the 59.6-74.4 GHz frequency range, and the rotational spectra of two conformational species, the chair-diketo and boat-diketo, and probably one excited vibrational state belonging to the chair-diketo form have been assigned. Quantum chemical calculations, performed at the B3LYP/6-311++G** and MP2/6-311++G** levels, were used to characterize the potential energy surface minima. The potential energy surface related to the interconversion of the observed diketonic species was modeled at the DFT level.

14.
J Am Med Dir Assoc ; 24(6): 765-772, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37054750

RESUMO

OBJECTIVES: To carry out a systematic review and meta-analysis to verify the effects of multicomponent training on the cognitive function of older adults without cognitive impairment. DESIGN: Systematic review and meta-analysis. SETTING AND PARTICIPANTS: Adults aged 60 years and older. METHODS: The searches were accomplished through MEDLINE (via PubMed), EMBASE, Cochrane Library, Web of Science, SCOPUS, LILACS, and Google Scholar databases. We performed the searches up to November 18, 2022. The study included only randomized controlled trials and older adults without any cognitive impairment (dementia, Alzheimer's, mild cognitive impairment, neurologic diseases). Risk of Bias 2 tool and PEDro scale was performed. RESULTS: Ten randomized controlled trials were included in the systematic review, of which 6 (involving 166 participants) were compiled in the meta-analysis of random effects models. The Mini-Mental State Examination and Montreal Cognitive Assessment were used to assess global cognitive function. The Trail-Making Test (TMT) (A and B domains) was performed by 4 studies. Compared with the control group, multicomponent training increases the global cognitive function (standardized mean difference = 0.58, 95% CI: 0.34-0.81, I2 = 11%; P < .001). Regarding TMT-A and TMT-B, multicomponent training decreases the time performed in the tests (TMT-A: mean difference = -6.70, 95% CI: -10.19 to -3.21; I2 = 51%; P = .0002) (TMT-B: mean difference = -8.80, 95% CI: -17.59 to -0.01; I2 = 69%; P = .05). The PEDro scale for the studies in our review ranged from 7 to 8 (mean = 7.4 ± 0.5), meaning good methodologic quality, and most studies were judged as at least low in terms of risk of bias. CONCLUSION AND IMPLICATIONS: Multicomponent training improves cognitive function in older adults without cognitive impairment. Therefore, a possible protective effect of multicomponent training for cognitive function in older adults is suggested.


Assuntos
Disfunção Cognitiva , Humanos , Pessoa de Meia-Idade , Idoso , Ensaios Clínicos Controlados Aleatórios como Assunto , Cognição , Testes de Estado Mental e Demência
15.
J Am Chem Soc ; 134(46): 19281-6, 2012 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-23127170

RESUMO

The dimer of acrylic acid can exist in two forms, depending on the entgegen or zusammen orientations of the two allyl groups. The latter one (zusammen) has a permanent value of the µ(b) dipole moment component, which allowed measuring its pulsed jet Fourier transform microwave (MW) spectrum. From the tunneling splitting, originating in the concerted proton transfer of the two carboxylic hydrogen atoms and measured for four isotopologues of such a bimolecule, we could determine the barrier and dynamics of the proton transfer.

16.
Chemistry ; 18(40): 12759-63, 2012 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-22915357

RESUMO

Two 1:1 adducts of ammonia with ethanol have been characterized by using pulsed-jet FT microwave spectroscopy. They are formed with two different (trans and gauche), stable conformers of ethanol. Several internal-dynamics effects are reflected in the features of the rotational spectra. The trans complex shows the tunneling effects owing to internal rotation of both ammonia and the methyl group. The rotational transitions of the gauche species exhibit a small splitting that is related to tunneling through the potential-energy barrier between the two equivalent minima.


Assuntos
Amônia/química , Etanol/química , Ligação de Hidrogênio , Modelos Moleculares , Simulação de Dinâmica Molecular , Análise Espectral , Estereoisomerismo
17.
Avian Dis ; 56(4 Suppl): 1021-4, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23402130

RESUMO

In the Veneto region (northern Italy), some geographic areas in the Po Valley have a large concentration of industrial poultry farms and are located close to wet areas with high populations of wild waterfowl. Live decoy birds belonging to the orders of Anseriformes and Charadriiformes can constitute a "bridge" for avian influenza (AI) viruses between the wild reservoir and the rural holdings where live decoy birds are usually kept, sometimes together with poultry. Thus, the use of live decoy birds during bird hunting could increase the risk of exposure of poultry farms to AI viruses. Since 2008, this kind of hunting has been strictly regulated with regard to the detection and use of live decoy birds. In order to guarantee the application of appropriate AI risk-modulating and monitoring measures in the management of the live decoys according to the European Union (EU) provisions, a solid and well-structured information system has been created. The Regional Data Bank (RDB) of farms and livestock, which has been operating since 1997, also contains data on farms and poultry movements. Therefore, the RDB management software was updated to collect data from the hunters who keep live decoy birds, and specific functions were integrated to ensure the traceability of these birds. Each live decoy bird has been identified by an irremovable ring. The individual code of each ring is recorded in the RDB and linked to both the holder's code and the hunting area. Transfers and death/slaughtering of the registered birds are recorded, too. The activation of a computerized data collection system has proven to be a prerequisite for the implementation of a control system for live decoy birds and provides an essential tool for the management of AI emergencies.


Assuntos
Criação de Animais Domésticos , Patos , Influenza Aviária/epidemiologia , Sistemas de Informação , Animais , Animais Selvagens , Surtos de Doenças/prevenção & controle , Surtos de Doenças/veterinária , Influenza Aviária/transmissão , Itália/epidemiologia
18.
J Travel Med ; 2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36331269

RESUMO

BACKGROUND: A new strain of WNV lineage 1 (WNV - 1) emerged in the Veneto Region, northern Italy, in 2021, eight years after the last outbreak of WNV - 1 in Italy. The virus, which co-circulates with WNV-2, has become endemic in the Region, where, in 2022, most human cases of neuroinvasive disease (WNND) reported in Europe have occurred. METHODS: Comparative analysis of the epidemiology and clinical presentation of WNV-1 and WNV-2 infection in humans, as well as the temporal and geographic distribution of WNV-1 and WNV-2 among wild birds and Culex pipiens mosquitoes in Veneto, from May 16th to August 21st, 2022, to determine if the high number of WNND cases was associated with WNV-1. RESULTS: As of August 21st, 2022, 222 human cases of WNV infection were confirmed by molecular testing, including 103 with fever (WNF) and 119 with WNND. WNV lineage was determined in 201 (90.5%) cases, comprising 138 WNV-1 and 63 WNV-2 infections. During the same period, 35 blood donors tested positive, including 30 in whom WNV lineage was determined (13 WNV-1 and 17 WNV-2). Comparative analysis of the distribution of WNV-1 and WNV-2 infections among WNND cases, WNF cases and WNV-positive blood donors showed that patients with WNND were more likely to have WNV-1 infection than blood donors (odds ratio 3.44; 95% CI 95% 1.54 to 8.24; p = 0.0043). As observed in humans, in wild birds WNV-1 had higher infectious rate (IR) and showed a more rapid expansion than WNV-2. At variance, the distribution of the two lineages was more even in mosquitoes, but with a trend of rapid increase of WNV-1 IR over WNV-2. CONCLUSIONS: Comparative analysis of WNV-1 vs WNV-2 infection in humans, wild birds, and mosquitos showed a rapid expansion of WNV-1 and suggested that WNV-1 infected patients might have an increased risk to develop severe disease.

19.
Phys Chem Chem Phys ; 13(31): 14092-6, 2011 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-21597624

RESUMO

We measured the molecular beam Fourier transform microwave spectra of six isotopologues of the 1 : 1 adduct of CH(3)CHClF with water. Water prefers to form an O-H···F rather than an O-H···Cl hydrogen bond. This is just the contrary of what was observed in the chlorofluoromethane-water adduct, where an O-H···Cl link was formed (W. Caminati, S. Melandri, A. Maris and P. Ottaviani, Angew. Chem., Int. Ed., 2006, 45, 2438). The water molecule is linked with an O-H···F bridge to the fluorine atom, with r(F···H(w)) = 2.14 Å, and with two C-H···O contacts to the alkyl hydrogens with r(C(1)-H(1)···O(w)) = 2.75 Å and r(C(2)-H(2)···O(w)) = 2.84 Å, respectively. Besides the rotational constants, the quadrupole coupling constants of the chlorine atom have been determined. In addition, information on the internal dynamics has been obtained.

20.
J Phys Chem A ; 115(34): 9585-9, 2011 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-21417381

RESUMO

The rotational spectra of five conformers of 1,3-butandiol have been measured by pulsed jet Fourier transform microwave spectroscopy. All of them are stabilized by an internal hydrogen bond and all of them have a GG' or a G'G arrangement of the two hydroxyl oxygens, which means that both oxygen atoms are on the same side with respect to the C1C2C3 plane. Apart from the spectroscopic constants, the relative abundances in the supersonic expansion are provided.


Assuntos
Butileno Glicóis/química , Físico-Química , Hidróxidos/química , Oxigênio/química , Ligação de Hidrogênio , Modelos Moleculares , Conformação Molecular , Rotação , Espectroscopia de Infravermelho com Transformada de Fourier , Estereoisomerismo , Termodinâmica
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