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The rotational spectrum of the most stable conformer of ethylene glycol (HO(CH 2 ) 2 OH) has been recorded between 360-890 GHz using a frequency-modulation submillimeter spectrometer. The refinement and extension of the spectroscopic parameters over previous efforts provide predicted catalog frequencies for ethylene glycol with sufficient accuracy for comparison to high-frequency astronomical data. The improvement in the cataloged line positions, and the need for improved accuracy enabled by high-frequency laboratory work, is demonstrated by an analysis of ethylene glycol emission at 890 GHz in the high-mass star-forming region NGC 6334I in ALMA Band 10 observations. The need for accurate rotational spectra at submillimeter wavelengths/THz frequencies is discussed.

The rotational spectrum of 15ND in its ground electronic X3Σ- state has been observed for the first time. Forty-three hyperfine-structure components belonging to the ground and ν = 1 vibrational states have been recorded with a frequency-modulation millimeter-/submillimeter-wave spectrometer. These new measurements, together with the ones available for the other isotopologues NH, ND, and 15NH, have been simultaneously analysed using the Dunham model to represent the ro-vibrational, fine, and hyperfine energy contributions. The least-squares fit of more than 1500 transitions yielded an extensive set of isotopically independent Ulm parameters plus 13 Born-Oppenheimer Breakdown coefficients Δlm. As an alternative approach, we performed a Dunham analysis in terms of the most abundant isotopologue coefficients Ylm and some isotopically dependent Born-Oppenheimer Breakdown constants δlm [R. J. Le Roy, J. Mol. Spectrosc., 1999, 194, 189]. The two fits provide results of equivalent quality. The Born-Oppenheimer equilibrium bond distance for the imidogen radical has been calculated [rBOe = 103.606721(13) pm] and zero-point energies have been derived for all the isotopologues.

N 6 -methyladenosine (m 6 A) regulates mRNA metabolism and translation, serving as an important source of post-transcriptional regulation. To date, the functional consequences of m 6 A deficiency within the adult brain have not been determined. To achieve m 6 A deficiency, we deleted Mettl14, an essential component of the m 6 A methyltransferase complex, in two related yet discrete mouse neuronal populations: striatonigral and striatopallidal. Mettl14 deletion reduced striatal m 6 A levels without altering cell numbers or morphology. Transcriptome-wide profiling of m 6 A-modified mRNAs in Mettl14-deleted striatum revealed downregulation of similar striatal mRNAs encoding neuron- and synapse-specific proteins in both neuronal types, but striatonigral and striatopallidal identity genes were uniquely downregulated in each respective manipulation. Upregulated mRNA species encoded non-neuron-specific proteins. These changes increased neuronal excitability, reduced spike frequency adaptation, and profoundly impaired striatal-mediated behaviors. Using viral-mediated, neuron-specific striatal Mettl14 deletion in adult mice, we further confirmed the significance of m 6 A in maintaining normal striatal function in the adult mouse., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Pressure broadening and pressure shift of N(2)H(+) rotational lines perturbed by collisions with He are studied for the first time using experiment and theory. Results are reported from measurements at 88 K for the rotational transitions j = 3<--2, 4<--3, 5<--4 and 6<--5 with frequencies ranging from 0.28 to 0.56 THz. The agreement between experiment and theoretical data derived from close coupling calculations confirms the reliability of a theoretical framework used for state-to-state transition rates of interest in the interpretation of spectroscopic data from interstellar molecular clouds. The influence of hyperfine effects on shifts and widths of the rotational lines is discussed in detail. Although in principle possible, experiment and theoretical considerations lead to the conclusion that hyperfine effects only play a minor role.

An experimental and theoretical study of pressure broadening and pressure shift of HCO(+) rotational lines perturbed by collisions with He is presented. Results are reported from measurements at 88 K for the lines j=4<--3, 5<--4 and 6<--5 with frequencies ranging from 0.35 to 0.54 THz. Using a new CCSD(T)/aug-cc-pVQZ potential energy surface for the He-HCO(+) interaction, the collisional line shape parameters are studied from fully quantum and semiclassical calculations. Results from the quantum treatment are in satisfactory agreement with experiments whereas the semiclassical approach can lead to appreciable differences. A study of the dependence of line width Gamma and shift s as a function of the translational energy shows the presence of quantum oscillations. Calculations on a previous Hartree-Fock-based potential energy surface lead to quite similar results for the collisional line shape parameters. Using a simplified version of the potential morphing method it is found that the line width Gamma is particularly sensitive to the long-range part of the potential energy surface. This also explains the success of the first line-broadening calculations which date back to the 1950s.

The unstable thioborine molecule and its deuterated variant have been produced by a high-temperature reaction between hydrogen sulfide and crystalline boron at 1100 degrees C in a flow system. Five rotational transitions from J = 2 <-- 1, to J = 6 <-- 5 have been recorded with sub-Doppler resolution for the vibrational ground state of H10/11BS and D10/11BS using the Lamb-dip technique. The hyperfine structure due to the electric quadrupole interaction of deuterium nucleus has been resolved yielding the first experimental determination of the deuterium quadrupole coupling constant in thioborine, which is 0.1403(75) MHz in D11 BS and 0.1360(38) MHz in D10BS. Fairly accurate values of 10/11B spin-rotation coupling constants and of the hydrogen-boron spin-spin coupling constants have also been determined. Additionally, the hyperfine structure of the rotational lines for the nu2 = 1 excited state has been investigated, thus obtaining information on the asymmetry of the electric field gradient at the B nucleus in the bending state.

An experimental and theoretical study of the pressure broadening and the pressure shift of three HCO(+) rotational lines (j=4<--3, 5<--4 and 6<--5) perturbed by collisions with Ar is presented. The measurements are carried out at 77 K and are compared to close-coupling calculations performed on an accurate potential energy surface for the Ar-HCO(+) interaction extending from small to very large separations between the ion and the perturber. For the pressure broadening, agreement between experiment and theory is satisfactory for both close-coupling and semiclassical calculations. For the pressure shift, however, close-coupling calculations are superior. The results agree with experiment in sign and order of magnitude, while semiclassical calculations are inaccurate for the shift of the presently studied lines because they neglect the contribution of strong collisions.

The rotational spectra of the unstable HCCCP molecule have been investigated in the millimeter-wave region for the main excited vibrational states which lie below 1000 cm(-1), namely nu(4) (C&bond;C stretch), nu(5) (HCC bend), nu(6) (CCC bend), nu(7) (CCP bend), 2nu(6), 2nu(7), 3nu(7), 4nu(7), nu(5) + nu(7), and nu(6) + nu(7). l-type resonance effects have been taken into account in the analysis of the spectra, so that the values of the anharmonicity constants x(L(66)), x(L(77)), x(L(57)), and x(L(67)) could be determined. The anharmonic interactions which couple the nu(4) state with nu(6) + nu(7), 2nu(6), and 4nu(7) have been also considered, yielding the unperturbed value of the alpha(4) vibration-rotation coupling constant. Copyright 2001 Academic Press.

The nuclear quadrupole hyperfine structure in rotational transitions of cis-1-chloro-2-fluoroethylene was measured for both (35)Cl and (37)Cl containing isotopomers in the millimeter-wave region. Near degeneracies of the 9(3,7) and 10(2,9) levels of (35)ClHC&dbond;CFH and of the 19(9,10/11) and 17(10,7/8) levels of (37)ClHC&dbond;CFH cause strong perturbations of the hyperfine patterns and give rise to perturbation-allowed DeltaJ = 2 and DeltaJ = 3 transitions. Lamb-dip measurements of such perturbed hyperfine patterns and of forbidden DeltaJ = +2 and perturbation-enhanced DeltaJ = 0 transitions of (35)ClHC&dbond;CFH provided an accurate determination of chi(ab), the off-diagonal element of the inertial nuclear quadrupole tensor. For (37)ClHC&dbond;CFH, chi(ab) was determined for the first time thanks to the observation of perturbed hyperfine patterns and of forbidden DeltaJ = +3 and DeltaJ = -2 transitions. Additional measurements of hyperfine structures led to improved values for the diagonal elements of the chi tensor of both (35)Cl and (37)Cl. Moreover, the complete inertial nuclear quadrupole tensor was evaluated from the field gradient at the chlorine nucleus computed by using the Multi-Configuration Self-Consistent Field (MCSCF) approach and employing basis sets of triple-zeta quality: very good agreement with the experiment was obtained. Copyright 2000 Academic Press.

The ground state rotational spectrum of fluoroacetylene was measured in the millimeter-wave and FIR regions up to 1280 GHz and J = 65. Very accurate values of the rotational and centrifugal distortion constants were determined and in particular a more reliable value of H0 = 2.0 10(-4) Hz has been obtained compared to that previously determined of -0.30 Hz. HCCF was prepared in a dc glow discharge in presence of 1,3,5-trifluorobenzene. Copyright 1998 Academic Press.

The hyperfine structure in the J = 1 <-- 0 and J = 2 <-- 1 transitions of 35Cl3CCH3 and 35Cl237ClCCH3 was resolved by utilizing the sub-Doppler resolution of a pulsed supersonic beam, cavity Fourier transform microwave (FTMW) spectrometer. The complete inertial and principal quadrupole tensors of the chlorine nuclei are determined. The symmetric top treatment for 35Cl3CCH3 and the asymmetric top treatment for 35Cl237ClCCH3 are found to yield identical results for the principal tensor components of the 35Cl nucleus. The quadrupole asymmetry parameter eta for the chlorine nuclei in 1,1,1-trichloroethane is small, which indicates nearly cylindrical symmetry of the field gradient. Nevertheless, there is evidence for some deviation of the z symmetry axis of the field gradient from the direction of the C-Cl bond. Copyright 1998 Academic Press.

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Objective: To determine if the spread of Clostridium difficile-associated diarrhea is related to the use of electronic thermometers in an acute hospital and a chronic healthcare facility., Design: After finding that a significant percentage (20.8%) of electronic rectal thermometer handles were contaminated with C difficile, all electronic thermometers were replaced with disposables. A before/after trial was conducted to determine if the change to disposable thermometers would reduce the incidence of C difficile-associated diarrhea., Setting: The study took place in a 343-bed acute hospital and a 538-bed skilled nursing facility., Patients: All patients who underwent routine microbiological evaluation for nosocomially acquired diarrhea over a 1-year period were included in the study. Nosocomial diarrhea was defined as 3 or more loose stools per day for 2 consecutive days and/or abdominal findings such as pain, distension, and ileus occurring 3 or more days after admission., Results: During the 6-month postintervention period, the incidence of C difficile-associated diarrhea was reduced from 2.71/1,000 patient days to 1.76/1,000 patient days in the acute hospital and from 0.41/1,000 patient days to 0.11/1,000 patient days in the skilled nursing facility. The protective effect of the intervention was statistically significant for both facilities., Conclusions: Replacement of electronic thermometers with single-use disposables significantly reduced the incidence of C difficile-associated diarrhea in both acute care and skilled nursing care facilities. Data suggest that the rectal route may be important in the transmission of C difficile in these settings.

Postoperative course and complications were studied as a function of the type of anesthesia, and the employ of a tracheotomy tube and gauze drainage of the laryngeal cavity, following partial vertical surgery on the larynx of 238 patients. Findings demonstrated that a general anesthetic by intubation with total skin closure without tracheotomy and gauze drainage of the laryngeal cavity, reduced the incidence of local infections complications and the duration of hospitalization. Without insisting on the advantages of this type of anesthesia and the value of immediate suturing, the authors note that these simple techniques markedly reduce the hospitalization period at a time when emphasis is being placed on the economic impact of the duration of this period.

The acute hemodynamic effects of ibopamine (SB-7505), the 3,4-diisobutyryl ester of N-methyldopamine which can be administered orally, were compared with those of dopamine. Ten male patients aged 54 years on average, with chronic congestive heart failure in NYHA (New York Heart Association) classes II-IV were studied. Eight of them were suffering from idiopathic congestive cardiomyopathy and two from ischemic cardiopathy. Baseline hemodynamic parameters were recorded within 24 h after withdrawal of previous treatment, the patients being kept on digitalis only. The investigation was carried out for a period of 3 days running. On day 1 of treatment one group of 5 patients were given dopamine at increasing doses of 2, 4 and 6 micrograms/kg/min. Their hemodynamic parameters were assessed 15 min after each dose and 15 and 60 min after withdrawal of the drug. Ibopamine was then administered orally in single doses of 50 mg on day 2 and 100 mg on day 3. The hemodynamic parameters were evaluated at 30, 60, 90, 120, 180, 360 and 480 min after administration. On day 1, another group of 5 patients were given 50 mg ibopamine, on day 2, 100 mg ibopamine and on day 3, dopamine. Hemodynamic data in this group of patients were evaluated at the same times mentioned above. The hemodynamic effects of ibopamine 100 mg are very similar to those obtained with 4 micrograms/kg/min dopamine. Indeed, the effects of both drugs on the cardiac index, right atrial pressure, peripheral and pulmonary vascular resistance do not differ significantly from each other.(ABSTRACT TRUNCATED AT 250 WORDS)

The Authors describe a patient with hypertrophic cardiomyopathy (HCM), severe left ventricular outflow tract obstruction and lack of response to beta-blockers or verapamil. Intravenous infusion of disopyramide resulted in a virtual disappearance of the LV pressure gradient, reduction of the systolic anterior motion of the mitral valve and slowing of the LV isovolumetric relaxation. One month after maintenance therapy with oral disopyramide a decrease of the anginal episodes and an improvement of the exercise tolerance were noted. Thus disopyramide, probably because of its negative inotropic action, is useful in the management of patients with HCM when LV outflow obstruction is the main cause of the clinical-hemodynamic findings.