Double resonant absorption measurement of acetylene symmetric vibrational states probed with cavity ring down spectroscopy

A novel mid-infrared/near-infrared double resonant absorption setup for studying infrared-inactive vibrational states is presented. A strong vibrational transition in the mid-infrared region is excited using an idler beam from a singly resonant continuous-wave optical parametric oscillator, to populate an intermediate vibrational state. High output power of the optical parametric oscillator and the strength of the mid-infrared transition result in efficient population transfer to the intermediate state, which allows measuring secondary transitions from this state with a high signal-to-noise ratio. A secondary, near-infrared transition from the intermediate state is probed using cavity ring down spectroscopy, which provides high sensitivity in this wavelength region. Due to the narrow linewidths of the excitation sources, the rovibrational lines of the secondary transition are measured with sub-Doppler resolution. The setup is used to access a previously unreported symmetric vibrational state of acetylene, $\nu_1+\nu_2+\nu_3+\nu_4^1+\nu_5^{-1}$ in the normal mode notation. Single-photon transitions to this state from the vibrational ground state are forbidden. Ten lines of the newly measured state are observed and fitted with the linear least-squares method to extract the band parameters. The vibrational term value was measured to be at 9775.0018(45) $\text{cm}^{-1}$, the rotational parameter $B$ was 1.162222 $\text{cm}^{-1}$, and the quartic centrifugal distortion parameter $D$ was 3.998(62)$\times 10^{-6} \text{cm}^{-1}$, where the numbers in the parenthesis are one-standard errors in the least significant digits

Electrostatic trapping of metastable NH molecules

We report on the Stark deceleration and electrostatic trapping of $^{14}$NH ($a ^1\Delta$) radicals. In the trap, the molecules are excited on the spin-forbidden $A ^3\Pi \leftarrow a ^1\Delta$ transition and detected via their subsequent fluorescence to the $X ^3\Sigma^-$ ground state. The 1/e trapping time is 1.4 $\pm$ 0.1 s, from which a lower limit of 2.7 s for the radiative lifetime of the $a ^1\Delta, v=0,J=2$ state is deduced. The spectral profile of the molecules in the trapping field is measured to probe their spatial distribution. Electrostatic trapping of metastable NH followed by optical pumping of the trapped molecules to the electronic ground state is an important step towards accumulation of these radicals in a magnetic trap.Comment: replaced with final version, added journal referenc

Preterm birth and the risk of multimorbidity in adolescence: a multiregister-based cohort study

BACKGROUND: Multimorbidity affects people of all ages, but the risk factors of multimorbidity in adolescence are unclear. The aim of this study was to examine preterm birth (<37 weeks) as a shared risk factor for multiple health outcomes and the role of gestational age (degree of prematurity) in the development of increasingly complex multimorbidity (two, three, or four health outcomes) in adolescence (age 10-18 years). METHODS: We used population-wide data from Finland (1 187 610 adolescents born 1987-2006) and Norway (555 431 adolescents born 1998-2007). Gestational age at birth was ascertained from medical birth registers and categorised as 23-27 weeks (extremely preterm), 28-31 weeks (very preterm), 32-33 weeks (moderately preterm), 34-36 weeks (late preterm), 37-38 weeks (early term), 39-41 weeks (term, reference category) and 42-44 weeks (post-term). Children who died or emigrated before their 10th birthday, and those with missing or implausible data on gestational age, birthweight, or covariates, were excluded. Health outcomes at age 10-18 years were ascertained from specialised health care and mortality registers. We calculated hazard ratios (HRs) and population attributable fractions (PAFs) with 95% CIs for multiple health outcomes during adolescence. FINDINGS: Individuals were followed up from age 10 to 18 years (mean follow-up: 6 years, SD: 3 years). Preterm birth was associated with increased risks of 20 hospital-treated malignant, cardiovascular, endocrinological, neuropsychiatric, respiratory, genitourinary, and congenital health outcomes, after correcting for multiple testing and ignoring small effects (HR <1·2). Confounder-adjusted HRs comparing preterm with term-born adolescents were 2·29 (95% CI 2·19-2·39) for two health outcomes (PAF 9·0%; 8·3-9·6), and 4·22 (3·66-4·87) for four health outcomes (PAF 22·7%; 19·4-25·8) in the Finnish data. Results in the Norwegian data showed a similar pattern. We observed a consistent dose-response relationship between an earlier gestational age and elevated risks of increasingly complex multimorbidity in both datasets. INTERPRETATION: Preterm birth is associated with increased risks of diverse multimorbidity patterns at age 10-18 years. Adolescents with a preterm-born background could benefit from diagnostic vigilance directed at multimorbidity and a multidisciplinary approach to health care. FUNDING: European Union Horizon 2020, Academy of Finland, Foundation for Pediatric Research, Sigrid Jusélius Foundation, Signe and Ane Gyllenberg Foundation

Cantilever-Enhanced Photoacoustic Spectroscopy of Radioactive Methane

We report the first high-resolution spectroscopy study of radiocarbon methane, 14CH4. Several absorption lines of the fundamental vibrational band v3 were measured using a continuous-wave mid-infrared optical parametric oscillator with cantilever-enhanced photoacoustic spectroscopy. © 2020 OSA.Peer reviewe

Cow's milk allergy in infancy and later development of type 1 diabetes-nationwide case-cohort study

Bakground: It is suggested that early intake of cow's milk could be a risk factor for type 1 diabetes (T1DM). Further, the different immunological background, gives a suggestion of an inverse relationship for the occurrence of these diseases. The aim of this study was to explore the association between cow's milk allergy (CMA) and the risk of T1DM in a register-based case-cohort study. Methods: Data were obtained from Finnish nationwide health registers. The study included all children born in Finland between January 01, 1986 and December 31, 2008 and diagnosed with T1DM before the age of 16 years (n = 7754). A 10% random sample from each birth year cohort was selected as a reference cohort (n = 137,798). T1DM, CMA, and asthma were defined based on valid special reimbursements for the costs of drugs/special formulas needed in the treatment of the diseases. Child's sex, birth decade, asthma, maternal diabetes and asthma, smoking during pregnancy, and previous deliveries were considered as confounding factors. Time-dependent, weighted Cox regression was applied for statistical analyses. Results: Children with CMA had an increased risk of developing T1DM in fully adjusted model (HR = 1.17; 95% CI 1.02-1.34), but the association was no longer observed when including the use of special infant formulas in the definition of CMA in the sensitivity analysis (HR = 1.11; 95% CI 0.92-1.32). CMA was associated with an increased risk of T1DM in children without asthma (HR = 1.27; 95%CI 1.10-1.47), but not in children with asthma (HR = 0.80; 95% CI 0.92-1.27). Conclusion: Children with CMA may have an increased risk of T1DM.Peer reviewe

L-Cysteine Containing Vitamin Supplement Which Prevents or Alleviates Alcohol-related Hangover Symptoms : Nausea, Headache, Stress and Anxiety

Correction ALCOHOL AND ALCOHOLISM Volume: 55 Issue: 6 Pages: 705-705 DOI: 10.1093/alcalc/agaa088 Published: NOV 2020Aims: Alcohol-related hangover symptoms: nausea, headache, stress and anxiety cause globally considerable amount of health problems and economic losses. Many of these harmful effects are produced by alcohol and its metabolite, acetaldehyde, which also is a common ingredient in alcohol beverages. The aim of the present study is to investigate the effect of the amino acid L-cysteine on the alcohol/acetaldehyde related aftereffects. Methods: Voluntary healthy participants were recruited through advertisements. Volunteers had to have experience of hangover and/or headache. The hangover study was randomized, double-blind and placebo-controlled. Nineteen males randomly swallowed placebo and L-cysteine tablets. The alcohol dose was 1.5 g/kg, which was consumed during 3 h. Results: The primary results based on correlational analysis showed that L-cysteine prevents or alleviates hangover, nausea, headache, stress and anxiety. For hangover, nausea and headache the results were apparent with the L-cysteine dose of 1200 mg and for stress and anxiety already with the dose of 600 mg. Conclusions: L-cysteine would reduce the need of drinking the next day with no or less hangover symptoms: nausea, headache, stress and anxiety. Altogether, these effects of L-cysteine are unique and seem to have a future in preventing or alleviating these harmful symptoms as well as reducing the risk of alcohol addiction.Peer reviewe

The radiative lifetime of metastable CO (a3Π,v=0a^3\Pi, v=0)

We present a combined experimental and theoretical study on the radiative lifetime of CO in the $a^3\Pi_{1,2}, v=0$ state. CO molecules in a beam are prepared in selected rotational levels of this metastable state, Stark-decelerated and electrostatically trapped. From the phosphorescence decay in the trap, the radiative lifetime is measured to be $2.63\pm0.03$ ms for the $a^3\Pi_1, v=0, J=1$ level. From spin-orbit coupling between the $a^3\Pi$ and the $A^1\Pi$ state a 20% longer radiative lifetime of 3.16 ms is calculated for this level. It is concluded that coupling to other $^1\Pi$ states contributes to the observed phosphorescence rate of metastable CO.Comment: replaced with final version, added journal referenc

Maternal antioxidant intake during pregnancy and the development of cows' milk allergy in the offspring

Cows' milk allergy (CMA) is the most common food allergy in young children, and it is often the first manifestation of atopic diseases. Accordingly, very early environmental factors, such as maternal diet during pregnancy, may play a role in the development of CMA, but the evidence is limited. The aim of this study was to investigate the association between maternal intake of antioxidant nutrients during pregnancy and the subsequent development of CMA in the offspring in a prospective, population-based birth cohort within the Finnish Type 1 Diabetes Prediction and Prevention Study. Maternal dietary information during pregnancy was collected with a detailed, validated FFQ. The maternal dietary information and the information on putative confounding factors were available for 4403 children. Information on diagnosed CMA (n 448) was obtained from a medical registry and queried from the parents up to child's age of 3 years. The Finnish food composition database was used to calculate the average daily intake of nutrients. Logistic regression was applied for statistical analyses, and the nutrient intakes were adjusted for energy intake. OR are presented per 1 sd increment of the particular nutrient intake. Maternal total and dietary intake of β-carotene was associated with an increased risk of CMA in the offspring when adjusted for the putative confounding factors (total OR 1·10, 95 % CI 1·02, 1·20; dietary OR 1·10; 95 % CI 1·01, 1·19). Using dietary supplements containing antioxidants in addition to a balanced diet may not confer any additional benefits