Sustained versus repetitive standing trunk extension results in greater spinal growth and pain improvement in back pain:A randomized clinical trial.

BACKGROUND: McKenzie standing trunk extension exercises have been used for the management of low back pain (LBP). However, no study to date has investigated the effect of standing trunk extension postures on spinal height and clinical outcomes. OBJECTIVE: To evaluate in subjects with LBP following a period of trunk loading how spinal height, pain, symptoms' centralization and function outcome measures respond to two standing postures interventions: (1) repetitive trunk extension (RTE) and (2) sustained trunk extension (STE). METHODS: A consecutive sample of convenience of people with LBP were recruited to participate in 2-session physical therapy using either RTE or STE in standing. RESULTS: Thirty participants (18 women) with a mean age of 53 ± 17.5 years completed the study. The first session resulted in spinal height increase (spinal growth) of 2.07 ± 1.32 mm for the RTE intervention and 4.54 ± 1.61 mm for the STE group (p< 0.001; ES = 1.67), while the second session (2-week following the first session) resulted in spinal growth of 2.39 ± 1.46 mm for the RTE group and 3.91 ± 2.06 mm for the STE group (p= 0.027; ES = 0.85). The STE group presented with the larger reduction in most pain from 6 to 2 as compared to the RTE group from 6 to 4 between Session 1 and Session 2 (p< 0.001). There was no difference between the groups in Modified Oswestry score and symptoms centralization (p= 0.88 and p= 0.77, respectively). CONCLUSION: People with LBP experienced greater spine growth and improvements of pain during standing STE as compared to RTE. People with LBP could use such postures and movements to alleviate their LBP and improve spine height while in a weight bearing position.

Recent Trends in Stratospheric Chlorine From Very Short-Lived Substances.

Very short-lived substances (VSLS), including dichloromethane (CH2Cl2), chloroform (CHCl3), perchloroethylene (C2Cl4), and 1,2-dichloroethane (C2H4Cl2), are a stratospheric chlorine source and therefore contribute to ozone depletion. We quantify stratospheric chlorine trends from these VSLS (VSLCltot) using a chemical transport model and atmospheric measurements, including novel high-altitude aircraft data from the NASA VIRGAS (2015) and POSIDON (2016) missions. We estimate VSLCltot increased from 69 (±14) parts per trillion (ppt) Cl in 2000 to 111 (±22) ppt Cl in 2017, with >80% delivered to the stratosphere through source gas injection, and the remainder from product gases. The modeled evolution of chlorine source gas injection agrees well with historical aircraft data, which corroborate reported surface CH2Cl2 increases since the mid-2000s. The relative contribution of VSLS to total stratospheric chlorine increased from ~2% in 2000 to ~3.4% in 2017, reflecting both VSLS growth and decreases in long-lived halocarbons. We derive a mean VSLCltot growth rate of 3.8 (±0.3) ppt Cl/year between 2004 and 2017, though year-to-year growth rates are variable and were small or negative in the period 2015-2017. Whether this is a transient effect, or longer-term stabilization, requires monitoring. In the upper stratosphere, the modeled rate of HCl decline (2004-2017) is -5.2% per decade with VSLS included, in good agreement to ACE satellite data (-4.8% per decade), and 15% slower than a model simulation without VSLS. Thus, VSLS have offset a portion of stratospheric chlorine reductions since the mid-2000s.

Demonstration of a mid-infrared cavity enhanced absorption spectrometer for breath acetone detection.

A high-resolution absorption spectrum of gaseous acetone near 8.2 µm has been taken using both Fourier transform and quantum cascade laser (QCL)-based infrared spectrometers. Absolute absorption cross sections within the 1215-1222 cm(-1) range have been determined, and the spectral window around 1216.5 cm(-1) (σ = 3.4 × 10(-19) cm(2) molecule(-1)) has been chosen for monitoring trace acetone in exhaled breath. Acetone at sub parts-per-million (ppm) levels has been measured in a breath sample with a precision of 0.17 ppm (1σ) by utilizing a cavity enhanced absorption spectrometer constructed from the QCL source and a linear, low-volume, optical cavity. The use of a water vapor trap ensured the accuracy of the results, which have been corroborated by mass spectrometric measurements.

Laboratory diagnosis of factitious disorder: a systematic review of tools useful in the diagnosis of Munchausen's syndrome.

AIMS: To assist clinicians in the diagnosis of factitious disorder. METHODS: This is a systematic review of the role of laboratory, radiologic, procedural, and pathological modalities to assist in the diagnosis of factitious disorder (Munchausen's syndrome). The review evaluated 3104 article titles and abstracts that were identified from MEDLINE as of January 2010. RESULTS: We found 190 articles that demonstrated techniques that will assist clinicians in recognizing fabricated manifestations of disease. The results are divided into 13 areas of clinical medicine for easy reference. They are further sub-divided by the diseases or conditions that patients have been reported to simulate and the diagnostic techniques suggested by the literature in each case. CONCLUSIONS: Factitious disorder is difficult to diagnose and may present as a wide array of fabricated conditions, but there are a range of laboratory and technical means available to assist clinicians in the 21st Century.

Magnetic circular dichroism and absorption spectra of methylidyne in a krypton matrix.

Electronic absorption and magnetic circular dichroism spectra are reported for the A(2)Δ, B(2)Σ(-), and C(2)Σ(+) ← X(2)Π transitions of methylidyne radicals isolated in a Kr matrix at cryogenic temperatures. The results are interpreted in the framework of a model in which the X(2)Π term is split by combination of spin-orbit and crystal-field interactions with the atoms of the host matrix. Analysis of the zeroth moments of the spectra yields an empirical spin-orbit coupling constant A(Π) = 11 ± 2 cm(-1) and orbital reduction factor κ = 0.26 ± 0.05, corresponding to a crystal-field splitting of V(Π) = 43 ± 10 cm(-1) for the X(2)Π term. For the A(2)Δ excited-state term, analysis of the first MCD moments gives a spin-orbit coupling constant of A(Δ) = 4.4 ± 0.9 cm(-1).

The rotational spectrum of CoF in all three spin-orbit components of the X3Phi i state.

The pure rotational spectrum of cobalt monofluoride in its X (3)Phi(i) electronic state has been measured in the frequency range of 256-651 GHz using direct absorption techniques. CoF was created by reacting cobalt vapor with F(2) in helium at low pressure (25-30 mTorr). All three spin components were identified in the spectrum of this species, two of which exhibited lambda doubling. Each spin component showed hyperfine splittings from both nuclei: an octet pattern arising from the (59)Co spin of I=72, which is further split into doublets due to the (19)F nucleus (I=12). The data were fitted close to experimental precision using an effective Hamiltonian expressed in Hund's case (a) form, and rotational, fine structure, hyperfine, and lambda-doubling parameters were determined. There is evidence that the rotational levels of the highest spin component (3)Phi(2) are perturbed. The r(0) bond length of CoF was estimated from the rotational constant to be 1.738 014(1) A. This value is in good agreement with previous studies but much more accurate. The matrix elements necessary for the complete treatment of Lambda doubling in a Phi state have been derived and are presented for the first time.

A molecular-beam optical Stark study of lines in the (1,0) band of the F4delta(7/2)-X4delta(7/2) transition of iron monohydride, FeH.

A supersonic molecular beam of iron monohydride, FeH, has been generated using a laser ablation/chemical reaction scheme and probed at near-natural linewidth resolution by optical Stark spectroscopy utilizing laser-induced fluorescence detection. The observed Stark splitting in Q(3.5) and R(3.5) lines of the F4delta(7/2) <-- X4delta(7/2) (1,0) transition were analyzed to determine values for the magnitudes of the permanent electric dipole moments, absolute value(mu), which were found to be 2.63(3) and 1.29(3) D for the X4delta (v = 0) and F4delta (v = 1) states, respectively. A comparison with ab initio theoretical predictions is made. The lambda doubling in the low-J levels of the F4delta(7/2) (v = 1) state is also modeled.

Magnetic circular dichroism and absorption spectra of phosphinidene in noble-gas matrices.

Electronic magnetic circular dichroism and absorption spectra are reported for the A 3pi(i) <-- X 3sigma- transitions of phosphinidene (PH) isolated in Ar, Kr, and Xe matrices at cryogenic temperatures (approximately 1.4-20 K) and over a range of magnetic field strengths (0-5 T). The results are analyzed by the method of moments, and parameters are extracted by fitting the experimental data to a model in which the A 3pi(i) term is split by spin-orbit (SO) coupling interactions, while the X 3sigma- term is split by spin-spin and higher-order SO coupling. The analysis indicates that, unlike the equivalent imidogen (NH) systems, ground-state PH radicals isolated in noble-gas matrices do not behave as free rotors. Trends in excited-state SO coupling constants are attributed to the external heavy-atom effect and guest-host orbital mixing. It is tentatively concluded that librational amplitudes of the guest radical decrease in the order Ar > Xe > Kr, probably as a consequence of competition between stronger guest-host interactions and larger matrix sites in heavier hosts.