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Recent frontiers in material development are represented by a class of so-called auxetic metamaterials that, thanks to their structure rather than composition, are characterized by a negative Poisson's ratio. In the present paper a two-dimensional auxetic plate, made by structural straight elements forming a lattice periodic structure with re-entrant cells, is considered. A thorough discussion on the linear and geometrically nonlinear deformability of the auxetic plate is presented. The key geometric parameters governing the deformability of the plate are identified, and some analytical expressions for calculating the Poisson's ratio, as a function of the applied strain, are given. Numerical (finite element) analyses and experimental tests on 3D printed specimens are carried out to verify the theoretical findings. For the latter ones, full field strain maps are obtained by means of a suitable interpolation of the sampled displacement field measured by digital image techniques.

The aim of this study was to retrospectively analyze the influence of a prophylaxis protocol of head and neck tumor (HNT) patients during and after intensity-modulated radiotherapy (IMRT).In this 5-year retrospective study (2009-2013), 70 (m 55, f 15; age range 28-8 years; median 58.7 years) out of 248 HNT patients of the Clinic of Cranio-Maxillofacial and Oral Surgery at the University of Zurich, Switzerland, fulfilled the inclusion criteria. Parameters of investigation were the salivary flow rates, possible dental foci and the dental status, oral side effects of radiotherapy, the prophylaxis protocol, and patient's compliance to this protocol. The following time points before during and after IMRT (6 weeks) were analyzed: prior to IMRT, 2-4 weeks, 6 weeks and 3, 6, and 12 months after the onset of radiotherapy.Unstimulated salivary flow rate, pH value of unstimulated salivary, and stimulated salivary flow rate showed a significant reduction over time (p0.001). One year after IMRT, both unstimulated and stimulated salivary flow showed a statistically significant lower salivary flow. The number of caries-affected sites per patient was significantly higher for patients with low compliance to the prophylaxis protocol (mean: low compliance 1.36, high compliance 0.26). Almost 75% of the evaluated patients suffered immediate gustatory change, and 47.1% showed signs of radiostomatitis through IMRT.High compliance to the prophylaxis protocol during and after radiotherapy is a key factor for the reduction of radiation side effects on dental hard tissue.High compliance to a monitored prophylaxis program is crucial for patients after head and neck surgery.

OBJETIVO: Estimar os fatores de risco associados ao óbito até 28 dias após o nascimento de recém-nascidos internados entre os anos de 2005 a 2007 em uma Unidade de Terapia Intensiva Neonatal de hospital privado no Município de Taubaté, usando a análise de regressão de Cox. MÉTODOS: Estudo epidemiológico do tipo longitudinal. Os dados foram obtidos de prontuários de todos os recém-nascidos internados na Unidade de Terapia Intensiva Neonatal, no período de janeiro de 2005 a dezembro de 2007. Foram obtidas variáveis maternas e relativas ao recém-nascido, sendo o desfecho primário a mortalidade neonatal. Foi feita a análise univariada, utilizando teste do qui-quadrado, risco relativo e gráfico de Kaplan-Meier para cada variável separadamente. A análise multivariada foi realizada por meio da regressão de Cox para verificar a associação de fatores maternos e neonatais ao desfecho primário. RESULTADOS: Foram estudados 185 neonatos, dos quais 10,5% foram a óbito antes do 28º dia de vida. As variáveis que se associaram de modo significante ao óbito no modelo de Cox foram: peso OBJETIVO: Estimar los factores de riesgo asociados al óbito hasta 28 días después del nacimiento de recién-nacidos inter-nados entre los años de 2005 y 2007 en una Unidad de Terapia Intensiva de un hospital privado en el Municipio de Taubaté (São Paulo, Brasil), usando el análisis de regresión de Cox. MÉTODOS: Estudio epidemiológico de tipo longitudinal. Los datos fueron obtenidos de prontuarios de todos los recién-nacidos internados en las UTI neonatal privadas en el periodo de enero/2005 a diciembre/2007. Se obtuvieron variables tanto maternas como relativas al recién-nacido y categorizadas, siendo el desfecho primario la mortalidad neonatal. Se realizó el análisis univariado utilizando la prueba de chi cuadrado, el riesgo relativo y la gráfica de Kaplan-Meier para cada variable en separado. El análisis multivariado fue realizado por medio de la regresión de Cox para verificar la asociación de factores maternos y neonatales al desfecho primario. RESULTADOS: Entraron en el estudio 185 neonatos, sien-do que 10,5% fueron a óbito antes del 28º día de vida. Las variables que se asociaron de modo significativo al óbito en el Modelo de Cox fueron: peso OBJECTIVE: To estimate the risk factors associated with neonatal deaths in a Neonatal Intensive Care Unit of a pri-vate hospital in the city of Taubaté (SP), Brazil, from 2005 to 2007, using the Cox regression analysis. METHODS: Longitudinal epidemiological study with data retrieved from medical records of all newborn admitted to a private Neonatal Intensive Care Unit from January 2005 to December 2007. The primary outcome was the neonatal mortality and independent variables were those concerning maternal and neonatal characteristics. Univariate analysis included chisquare test, relative risk and the Kaplan-Meier survival plot for each variable. Multivariate analysis to test association of independent variables with neonatal mortal-ity was performed by Cox regression analysis. RESULTS: 185 neonates were enrolled in the study and 10.5% died before the 28th day of life. Variables that were significantly associated to neonatal death by the Cox regression analysis model were birthweight

Summary What is known and objective Dantrolene can be combined with baclofen to better treat spasticity, but may cause muscular weakness and dysphagia. We instead describe a pharyngeal spasm due to dantrolene. Case summary A 12-year-old male received dantrolene 3 mg/kg/day in adjunct to baclofen 2 mg/kg/day, to improve spasticity. After 5 days of full-dose dantrolene, his dysphagia worsened and he developed pharyngeal spasm. Dantrolene was suspected for an adverse reaction and removed. The patient subsequently improved. What is new and conclusion Causality analysis determined a probable relationship between dantrolene and pharyngeal spasm. This may be due to direct muscle contraction by dantrolene, an effect seen previously in vitro.

The response of silicon strip detectors exposed to energetic heavy ions in the energy interval from 0.3 up to 1.4 GeV/u has been measured at the SIS accelerator at GSI. The energy deposit spectra are characterized by their mean values and widths. The carbon data, at various energies, agree within the accuracy of the measurements with the computed response of the detector. The measured widths of the energy deposit spectra for ruthenium are narrower than those calculated by the appropriate Vavilov distributions. Energetic δ-rays overflowing from the silicon detector is considered as a possible explanation for the disagreement between computed and measured widths.

The complex Cp*Zr(2,6-OC6H3tBu2)Cl2 (Cp* = η5-C5Me5) (1) has been prepared by the reaction of the starting material Cp*ZrCl3 and 1 equiv of the lithium salt of the phenol compound. The reactions of...

Far-infrared emission spectroscopy has beendemonstrated to be a valuable method for remotesensing of trace species in the stratosphere, with theability to simultaneously detect a number of keychemical species. SAFIRE-A is a new far-infraredFourier Transform (FT) spectrometer which has beenspecifically designed to operate on board of a highaltitude aircraft in the lower stratosphere and uppertroposphere regions where relatively few remotesensing measurements have been made. Using newtechnology, the sensitivity of the FT spectrometermethod has been substantially improved for the longwavelength region. Results are reported formeasurements of O3, HNO3 and N2O at 17and 19 km using a detection window near 23 cm-1.Geographical and altitude variability of the volumemixing ratio of these constituents and their relativecorrelation are discussed. Ozone measurements agreewell with in situ measurements, except in regions ofstrong stirring and mixing associated with deformationof the northern vortex edge. Whilst SAFIREmeasurements of trace gases do not capture all of thelocal variability seen by rapid in-situ techniques,they can indicate horizontal variability close to, butnot intercepted by, the aircraft's flight path. Apossible detection of ClO at the low background levelsexpected outside the polar vortex is also reported.

A bolometer was flown as an infrared detector on a stratospheric aircraft at altitudes of approximately 19 km during the APE campaign, which took place in Rovaniemi (Finland) in the period December 1996–January 1997. The signal impulses produced in the bolometer by the thermalisation of the ionisation induced by cosmic charged particles in the sensitive layer of the detector have been analysed. A statistics of approximately 4000 cosmic-ray events was recorded during four flights. In the period of the observations the solar activity was near its minimum. The observations from a stratospheric aircraft has made possible the collection of a first sampling of cosmic-ray flux variation with latitude and altitude. A comparison is made with previous balloon observations at the same altitudes. Model calculations are compared to the observed cosmic-ray energy loss distribution in the bolometer. The results are useful for the understanding of cosmic-ray background effects occurring in applications of high sensitivity bolometers in aircraft-borne measurements.

The design of the fine grained 300 t liquid argon calorimeter BARS is described. The BARS electronics include about 30 K channels of low noise amplifiers and ADCs. The DAQ system makes it possible to select channels with signals above the chosen threshold. 48 scintillation hodoscopes placed inside the liquid argon are used to form the first level trigger. The total number of scintillation counters in liquid argon is 384. Sums of ionization signals are used to produce the second level trigger. Results of the first use of liquid argon calorimetry for the measurements of tagged neutrino interactions, cosmic-ray muon spectra and composition of extensive atmospheric showers are discussed.

Reaction of the binuclear alkoxide species [Nb(Cl)3(OR)2]2 (R = Me, Et) with potassium hydridotris(3,5-dimethylpyrazol-1-yl)borate, KTp*, leads to Tp*Nb(O)(Cl)(OR) (R = Me (1), Et (2)). These compl...

Thermal treatment of Nb(η5-C5H4SiMe3)2(H)3 (1) with the appropriate organogermanium hydrides (HGeR3) and HSnPh3 gives the corresponding niobocene germyl hydrides Nb(η5-C5H4SiMe3)2(H)2(GeR3), GeR3GePh3 (2), GePh2H (3), GeEt3 (4), Ge(C6H13)3 (5), GeiAm3 (iAm = CH2CH2CH(CH3)2) (6), Ge(C6H13)2Cl (7), GeiAm2Cl (8), Ge(C6H13)2H (9), GeiAm2H (10), and Nb(η5-C5H4SiMe3)2(H)2(SnPh3) (11) in good yields. Spectroscopic data indicate the presence of only one of the two possible structural isomers in which the germyl or stannyl group is in the equatorial plane with a symmetrical structure. Reactivity studies on the series Nb(η5-C5H4SiMe3)2(H)2(ER3), E = Si (12), Ge (2), Sn (11), were carried out. 12 reacts with H2 to give 1, but 2 and 11 were unreactive toward this reagent. Furthermore, a similar behavior was observed with CO and CN(2,6-Me2C6H3). Thus, 12 reacts with these reagents to give rise, after elimination of HSiPh3, to Nb(η5-C5H4SiMe3)2(H)(CO) and Nb(η5-C5H4SiMe3)2(H)(CN(2,6-Me2C6H3)), respectively, while 2 and...

The hydride isocyanide complexes, Nb(η5-C5H4SiMe3)2(H)(CNR), R = xylyl = 2,6-dimethylphenyl; Cy (cyclohexyl); tBu; as well as the hydride carbonyl complex Nb(η5-C5H4SiMe3)2(H)(CO) react with severa...

A charge preamplifier with a large dynamic range and related readout system has been designed, constructed and tested. It is dedicated to the readout of silicon multistrip detectors for cosmic ray experiments in space. The charge dynamic range extends from fractions of minimum ionizing particles (MIPs) up to 16 000 MIPs covering all nuclides of the periodic chart of elements in the relativistic regime. The power consumption per channel is 48 mW and may be reduced to 26 mW by limiting the charge dynamic to 1–8000 MIPs. The noise, at room temperature, amounts to 1185 ENC electrons with a detector capacitance of 470 pF. The measured integral non-linearity in the full range 1–16 000 MIPs is less than 0.5%. Performance results with electrons from 90Sr, with alpha particles from 241Am and with cosmic ray ground muons are presented.

The effect of the phenanthroline substituents on the structure and reactivity of platinum(II) and platinum(IV) complexes has been investigated. The X-ray crystal structures of the compounds [PtI(2)(4,7-Ph(2)phen)].CHCl(3) (1dz.CHCl(3)), [PtI(4)(4,7-Ph(2)phen)].CHCl(3) (2dz.CHCl(3)), [PtI(2)(2,9-Me(2)-4,7-Ph(2)phen)] (1fz), and [PtI(4)(2,9-Me(2)-4,7-Ph(2)phen)].I(2) (2fz.I(2)) have shown that complexes 1fz and 2fz, containing ortho-substituted phenanthrolines, exhibit a remarkable displacement of the equatorial iodine atoms from the N-Pt-N' plane (average 0.477(2) and 0.199(2) Å, respectively), a bending of the phenanthroline [angle between outer rings of 19.9(7) and 14.2(7) degrees, respectively] and a rotation of the N-C-C'-N' plane with respect to the N-Pt-N' plane [32.3(10) and 26.5(9) degrees, respectively]. Comparison between the structures of 1fz and 2fz, both having the phenanthroline with methyl substituents in the ortho position, indicates that, in the latter case, because of the presence of the two axial iodine ligands, the displacements of the ligands from the equatorial plane are smaller and find a compensation in a narrowing of the I(1)-Pt-I(1') angle (5 degrees ) and a lengthening of the Pt-N bonds (0.07 Å). The electrochemical behavior of the four-coordinate platinum(II) complexes shows that compounds possessing regular planar geometry have access to the one-electron reduced species, whereas those with distorted coordination geometry are irreversibly reduced by collapsing of the complex geometry. This is in sharp contrast with the behavior of related nickel complexes for which the pseudo-tetrahedral coordination imposed by bulky 2,9-substituents of phenanthroline stabilizes the nickel(I) species. Spectroscopic results allow us to assign a significant Pt(I) character to [1d](-) monoanions. The electrogenerated, plus one electron, complexes are not indefinitely stable and, because of conjugation with the phen ligand, progressively restore the Pt(II) oxidation state by transferring the electron to the peripheral organic ligand. The latter process can involve multiple electron additions in the macroelectrolysis time scale. The related platinum(IV) complexes [PtX(4)(L)] undergo irreversible two-electron reduction accompanied by fast release of the axial ligands and formation of the corresponding platinum(II) species.

The reactions of Nb(C5H3RR‘)2Cl2 with Red−Al followed by hydrolysis yield Nb(C5H3RR‘)2H3 (R = R‘ = H, 1; R = H, R‘ = SiMe3, 2; R = R‘ = SiMe3, 3). These compounds react with Lewis acidic coinage cationic species, namely, [Cu(MeCN)4]PF6, AgBF4, and “Au(THT)PF6”, prepared in situ from AuCl(THT) and TlPF6 in a 2 to 1 ratio to yield the adducts [{Nb(C5H3RR‘)2H3}2M]+ (M = Cu, R = R‘ = H, 7; R = H, R‘ = SiMe3, 8; R = R‘ = SiMe3, 9; M = Ag, R = H, R‘ = SiMe3, 10; R = R‘ = SiMe3, 11; M = Au, R = R‘ = H, 12; R = H, R‘ = SiMe3, 13; R = R‘ = SiMe3, 14). Like 1, but unlike the corresponding tantalum derivatives Ta(C5H3RR‘)2H3 (R = R‘ = H, 4; R = H, R‘ = SiMe3, 5; R = R‘ = SiMe3, 6), 2 and 3 show exchange couplings in their high-field 1H NMR spectra due to a hydride tunneling phenomenon. The magnitudes of exchange couplings are larger in the cases of 2 and 3 than in the case of 1 as a result of the decrease of electron density upon increasing the number of SiMe3 substituents on the Cp ring. The addition of a Lewis aci...

The synthesis of a novel lithium compound [{Li(H2O)(bdmpza)}4] [bdmpza = bis(3,5-dimethylpyrazol-1-yl)acetate], containing a new “scorpionate” ligand, and its reaction with a niobium complex to give [NbCl3(bdmpza)(PhCCMe)] have been reported.

A total of 60 samples of dry sausages were analyzed (50 of "salami" and 10 of "chorizo" "candelario" type) obtained at random in markets authorized for their commercialization, for the purpose of evidencing the presence of bacteria of the genus Listeria (Listeria monocytogenes and Listeria spp.). The results obtained in salami were the following: 10 (20%) isolates of Listeria spp., were characterized: 1 (2%) strain as L. monocytogenes type 1, 7 (14%) strains as L. innocua, 2 (4%) strains as L. welshimeri. In chorizo candelario type 6 (60%) isolates of Listeria spp., were characterized: 2 (33%) strains as L. monocytogenes type 1 and 4 (66%) strains as L. innocua. The total percentages of isolations were: 26.6% of Listeria spp., 5% of L. monocytogenes type 1, 18.3% of L. innocua and 3.3% of L. welshimeri. In conclusion, we consider that methodologies of control must be developed and implemented in order to guarantee the inocuity of these products.

The reaction of Haat [Haat = (3-acetylamino-1,2,4-triazole)] with aquated Cu(CF3SO3)2, Cu(NO3)2, and Cu(ClO4)2, respectively, in water results in the trinuclear complexes [Cu3(OH)(aat)3(CF3SO3)(H2O)2](CF3SO3) (1), [Cu3(OH)(aat)3(NO3)(H2O)2](NO3).(H2O)2 (2), and [Cu3(OH)(aat)3(ClO4)(H2O)2](ClO4) (3). The synthesis, X-ray structure, and magnetic and spectroscopic properties of the three title complexes are described. The cation of the three complexes is trinuclear with a Cu3OH skeleton which has the N-N diazine grouping of a triazole ring as bridge between each pair of copper atoms. The Cu3OH units have an average Cu-O distance of 1.991(6) (1), 2.000(6) (2), and 2.007(6) (3) A, an average Cu-Cu' distance of 3.355(2) (1), 3.341(1) (2), and 3.371(3) (3) A, and an average Cu-O-Cu' angle of 114.6(3) degrees (1), 112.4(2) degrees (2), and 115.4(3) degrees (3). The existence of the Cu3OH fragment is confirmed by a pseudotetrahedral oxygen environment, by detection of the OH hydrogen atom, and by stoichiometry. In the trinuclear unit the metal ions show, in the first approximation, a pseudo-square-planar pyramidal environment forming a CuN2O3 chromophore; three of the basal positions are occupied by N,N,O aat ligand atoms, the fourth one is occupied by the oxygen of the central OH group, and the apical site is occupied by an oxygen atom from a water molecule in the case of two of the copper(II) atoms and by an oxygen atom from the coordinating anion in the case of the third metal ion. The three compounds exhibit strong antiferromagnetic interaction, with similar J constants [J = -197.7 (1), J = -190.9 (2), J = -198.2 (3) cm-1], reaching complete spin coupling at ca. 75 K (1)/55 K (2)/95 K (3). At very low temperature the magnetic moment (magnetic susceptibility) falls below that expected for one unpaired electron. Magnetic parameters are discussed on the basis of the structural results and compared with those reported in the literature for related trimeric Cu(II) compounds with N-O or N-N peripheral bridges. Solid state EPR spectra of the three complexes recorded at liquid N temperature show axial signals. Crystal data: C14H20Cu3F6N12O12S2 (1) (Mw = 917.16) crystallizes in the monoclinic space group, P2(1)/c, Z = 4, with cell dimensions a = 13.080(2) A, b = 17.202(2) A, c = 13.840(2) A, beta = 92.40(1) degrees, and V = 3111.3(7) A3, Dcalcd = 1.958 Mg m-3; the final agreement values were R1 = 0.0582 and wR2 = 0.1462 for 7107 unique reflections. C12H24Cu3N14O14 (2) (Mw = 779.07) crystallizes in the triclinic space group, P1, Z = 2, with cell dimensions a = 9.647(2) A, b = 9.985(2) A, c = 15.314(2) A, alpha = 84.080(10), beta = 87.694(10), gamma = 65.030(10) degrees, and V = 1330.1(4) A3, Dcalcd = 1.945 Mg m-3; the final agreement values were R1 = 0.0397 and wR2 = 0.0950 for 7728 unique reflections. C12H20Cl2Cu3N12O14 (3) (Mw = 817.92) crystallizes in the monoclinic space group, P2(1)/a, Z = 4, with cell dimensions a = 14.238(5) A, b = 16.387(6) A, c = 11.678(4) A, gamma = 90.45(2) degrees, and V = 2724.6(18) A3, Dcalcd = 1.994 Mg m-3; the final agreement values were R1 = 0.0616 and wR2 = 0.1279 for 4038 unique reflections.

Reaction of Cp2M(PMe3)(2) complexes (M = Ti, Zr; Cp = eta(5)-C5H5) with the N-(p-tolyl)-diphenylketenimine Ph'N=C=CPh2 (Ph' = p-MeC6H4) in a 1:1 molar ratio affords the ketenimine-containing metallocene derivatives Cp2M(eta(2)-(C,N)-Ph'N=C=CPh2)(PMe3) (M = Ti (1); Zr (2)). The ketenimine ligand reacts in the same way with the ''Cp*M-2'' species (Cp* = eta(5)-C5Me5) generated from the reduction of the corresponding Cp*2MCl2 complexes with (LiBu)-Bu-t (1:2 molar ratio) to give the related complexes Cp*M-2(eta(2)-(C,N)-Ph'N=C=CPh2) (M = Ti (3); Zr (4)). The molecular structure of 3 shows a titanium atom bonded to two eta(5)-cyclopentadienyl rings and a eta(2)-(C,N)-bonded ketenimine ligand. Reaction of ''Cp*Ti-2'' with the ketenimine ligand in a 1:2 molar ratio gives 1,1,5,5-tetraphenyl-3-(p-tolyl)-2-(p-toluidino)-3-aza-1,4-pentadiene, which probably results from the coupling, followed by hydrolysis, of two ketenimine molecules coordinated to one titanocene moiety. Protonation of 3 with Et3NHCl or H2O (1:1 molar ratio) affords the intermediate species Cp*Ti-2(X)(eta(2)-(C,N)-Ph'N=C(H)=CPh2) (X = Cl (5); OH (6)), which on hydrolysis evolves to give the enamine Ph'N(H)-CH=CPh2 as the final product. Finally, 3 reacts reversibly with H-2 to give the hydride enamidate complex Cp*Ti-2(H)(eta(1)-Ph'N-CH=CPh2) (7). The structures of the different compounds have been determined by IR and NMR spectroscopic methods.

We have constructed and operated charge preamplifiers for silicon strip detectors with a dynamic range extending from fractions of minimum ionising particle (MIP) up to 16 124 MIPs. These silicon detectors combined with time-of-flight counters and cesium iodide scintillator form a segment of the VENUS detector that has been exposed to a calcium beam of 0.5 GeV/u at the GSI accelerator. The aim of the instrument is the identification of all nuclides of the periodic table of the elements. Measurements of electronic noise, cross-talk among channels and energy deposit resolutions in various experimental conditions for silicon detectors are given. The measured light output of the CsI(Tl) crystal induced by calcium is compared with that extrapolated from lower-energy data of various nuclide species determined in other experiments. The charge resolution for calcium ions, determined by the d E d χ detectors and TOF counters of time resolution of 55 ± 7 ps, amounts to 0.42 charge units (rms). Improvements in ion discrimination with respect to the present detector configuration are considered.