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AIM This study explored hypoglycaemia and metabolic crises, including hyperketosis, in patients with spinal muscular atrophy (SMA). METHODS The study comprised four adolescents aged 15-17 and six adults aged 19-37 with SMA type II and eight adult controls aged 21-41, who were recruited by the Rigshospitalet, Denmark, from May 1st to October 30th 2017. We used stable isotope technique and indirect calorimetry to investigate fat and glucose metabolism during a 24-h fast or until hypoglycaemia occurred. RESULTS All patients with SMA II developed moderate to severe hyperketosis and 60% had symptoms of hypoglycaemia or blood glucose levels below 3 mmol/L. None of the controls developed hyperketosis or hypoglycaemia. Plasma bicarbonate decreased, in line with increased ketone bodies, indicating the start of metabolic acidosis in patients with SMA II. Increased fat production and utilisation were seen in healthy controls during the fasting period, but were absent in patients with SMA II, indicating blunted fat oxidation. CONCLUSION Low skeletal muscle mass was the best explanation for why patients with SMA II had an increased risk of hypoglycaemia, hyperketosis, metabolic acidosis and disturbed fat and glucose metabolism during fasting. These risks have implications for children facing surgery and those with severe illnesses.

HYPRFlow is a novel imaging strategy that provides fast, high-resolution contrast-enhanced time-resolved images and measurement of the velocity of the entire cerebrovascular system. Our hypothesis was that the images obtained with this strategy are of adequate diagnostic image quality to delineate the major components of AVMs.HYPRFlow and 3D TOF scans were obtained in 21 patients with AVMs with correlative DSA examinations in 14 patients. The examinations were scored for image quality and graded by using the Spetzler-Martin criteria. Mean arterial transit time and overlap integrals were calculated from the dynamic image data. Volume flow rates in normal arteries and AVM feeding arteries were measured from the phase contrast data.HYPRFlow was equivalent to 3D-TOF in delineating normal arterial anatomy, arterial feeders, and nidus size and was concordant with DSA for AVM grading and venous drainage in 13 of the 14 examinations. Mean arterial transit time on the AVM side was 0.49 seconds, and on the normal contralateral side, 2.53 seconds with P.001. Across all 21 subjects, the mean arterial volume flow rate in the M1 segment ipsilateral to the AVM was 4.07 ± 3.04 mL/s; on the contralateral M1 segment, it was 2.09 ± 0.64 mL/s. The mean volume flow rate in the largest feeding artery to the AVM was 3.86 ± 2.74 mL/s.HYPRFlow provides an alternative approach to the MRA evaluation of AVMs, with the advantages of increased coverage, 0.75-second temporal resolution, 0.68-mm isotropic spatial resolution, and quantitative measurement of flow in 6 minutes.

To provide new determinations of the Boltzmann constant, k, which has been asked for by the International Committee for Weights and Measures concerning preparative steps towards new definitions of the kilogram, the ampere, the kelvin and the mole, an iMERAPlus joint research project has coordinated the European activities in this field. In this major European research project the Boltzmann constant has been determined by various methods to support the new definition of the kelvin. The final results of the project are reviewed in this paper. Determinations of the Boltzmann constant k were achieved within the project by all three envisaged methods: acoustic gas thermometry, Doppler broadening technique, and dielectric constant gas thermometry. The results were exploited by the interdisciplinary Committee on Data for Science and Technology (CODATA) in their 2010 adjustment of recommended values for fundamental constants. As a result, the CODATA group recommended a value for k with a relative standard uncertainty about a factor of two smaller than the previous u(k)/k of 1.7×10−6.

Recently, hollow-core photonic bandgap fibers (HC-PBFs) for use in the 2 μm wavelength region have become available. We have employed tunable diode laser absorption spectroscopy (TDLAS) to quantify CO2 in nitrogen, injected into a HC-PBF. Our spectrometer contains both an HC-PBF-based absorption cell and an astigmatic Herriott multipass gas cell. The Herriott cell was used for comparison with the HC-PBF cell. The HC-PBF cell’s sensitivity and limit of detection were calculated to be 3.5×10−4 cm−1⋅Hz−1/2 and 59 ppm⋅m, respectively. To substantiate the spectrometer performance, a measurement was done in the Herriott cell probing a reference gas mixture with nominal 400 μmol/mol CO2 in N2. The spectrometric results were in good agreement with the reference value. The relative standard uncertainty of the spectrometric result was found to be at the ±2 % level.

The influence of 25 kHz ultrasound and cathode rotation during electroplating of Ni films on Si wafers has been studied with respect to intrinsic stress formation. Current densities from 1·6 up to 28·3 A dm−2 were used in an additive free Ni sulphamate electrolyte. In general, more efficient agitation by either ultrasound or cathode rotation was found to reduce intrinsic stress towards compressive levels compared with conventional agitation with an electrolyte circulation pump. Furthermore, intrinsic stresses become less dependent on changes in current density. The latter effect is most pronounced for ultrasonic agitation. Structure analysis of samples deposited by ultrasonic agitation shows dense deposits with initially smaller grains at high ultrasonic effect. Locally increased temperature at the substrate surface could be an important effect of ultrasound agitation.

A direct phase coherent determination of the absolute frequency of the a15 component in the R(12) 26-0 and b10 component in the R(106) 28-0 transitions in 127I2 at 543 nm has been made at the International Bureau of Weights and Measures. Lasers from the Czech Metrology Institute (Czech Republic), the National Institute of Metrology (China), the Centro Nacional de Metrologia (Mexico), the Standards, Productivity and Innovation Board (Singapore), the Centre for Metrology and Accreditation (Finland), the Danish Institute of Fundamental Metrology (Denmark), the National Physical Laboratory (U.K.), and the International Bureau of Weights and Measures took part. The mean frequency values found are f(a15)=551579856480.4 kHz, uc=4.8 kHz and f(b10)=551580162397.1 kHz, uc=4.6 kHz for the current group of lasers, where uc is the combined standard uncertainty. This constitutes a 30-fold improvement in accuracy for this radiation, which is recommended for the realization of the definition of the meter. If only lasers equipped with an iodine cell temperature control are considered, the group of lasers shows a dispersion of 7 kHz. This value is indicative of the level of reproducibility that can be expected at present for this type of standard

We describe a 7.4-μm source based on difference frequency generation with 6.5 mW of 1278-nm radiation from an extended cavity laser and 66 mW of 1544-nm radiation from another extended cavity laser, amplified in an erbium-doped fibre amplifier. Optimum focusing of the input beams in the 5×5×10-mm3 AgGaSe2 crystal, and the spatial and temporal characteristics of the output beam, are determined. The source is used for accurate determination of line parameters for selected lines of the ν3 band of SO2, centred at 1361 cm-1. Subsequently, these lines are used for performing quantitative analysis of gas mixtures containing SO2 at concentration levels down to 4 ppm without relying on any calibration with certified gas mixtures. This demonstrates the potential of infrared spectroscopy as a primary method for low-concentration gas analysis.

Effective CW second harmonic generation often utilizes a nonlinear crystal in a ring cavity with two curved mirrors of identical radius of curvature and one or two plane mirrors. When a Brewster-cut crystal is used, the cavity losses can be significantly smaller than for an anti-reflection (AR)-coated crystal cut for normal incidence. However, we find that the loss reduction is achieved at the expense of a reduction in the effective nonlinearity. We calculate the theoretical performance of a setup with a Brewster-cut crystal and compare the results with a setup where a normal-cut AR-coated crystal is used.

PURPOSE To find reliable data of the incidence of different variations of the spine. MATERIAL AND METHODS Standardised radiographic examinations of 10,922 young, healthy pilot aspirants of the German air force were made. Radiographic examination included the whole spine in a.p. and lateral projection, the cervical spine in oblique projection and in a subunit of 5781 men the lumbar spine in oblique projection. RESULTS The following incidences were found: mild habit scoliosis: 80.4%, structural scoliosis: 9%, severe thoracal kyphosis without severe lumbar lordosis: 5.1% and together with severe lumbar lordosis: 30.8%, mild forms of kyphosis of adolescence: 23.3%, severe forms: 2.1% and cuneiform deformation of vertebral body: 4.9%, sacralization: 7.8%, lumbarization: 5.9%, spondylolysis: 6.2%, spondylolisthesis: 4.3% and lumbar chondrosis: 2.1%. Chondrosis of the thoracal and cervical spine, osteochondrosis and coalescent vertebral bodies were found in less than 0.8% each. CONCLUSION In only 2.6% were there no pathological findings. This shows importance of radiological spine examinations especially for industrial and preventive medicine.

This study provides data on prevalence of Staphylococcus aureus in oropharynx, rhinopharynx and vestibulum nasi. Specimens were taken from these three pharyngeal sites in 346 patients and analysed for S. aureus. Abnormal pharyngeal findings and patient histories were recorded. S. aureus was found in 8.1%, 7.2% and 20.2% of all specimens from oropharynx, rhinopharynx and vestibulum nasi, respectively. A strong association between colonization of oropharynx and rhinopharynx was found, especially when vestibulum nasi was not colonized. These findings can be used in development of more effective meticillin-resistant Staphylococcus aureus decolonization regimes.

During a 10-year period, 159 benign submandibular gland excisions were performed in 157 patients. 86 of the patients were available for follow-up evaluation. Both short- and long-term complications were listed. Neurapraxia to the mandibular branch of the facial nerve was frequent after the operation, but restoration of function was seen in 92.3%. Scar problems, sensation changes, reduced salivation and taste perception were noticed by the patients in several cases, but rarely caused dissatisfaction. 18.2% of the patients in the salivary stone group had residual stones in Wharton's duct after the operation. The indication for removal of both glands should be carefully considered because of development of xerostomia.

We present the first experimental determination of the electric-dipole forbidden $(3s3p)^{3}P_{2}\ensuremath{\rightarrow}(3{s}^{2})^{1}S_{0}$ ($M2$) transition rate in $^{24}\mathrm{Mg}$ and compare to state-of-the-art theoretical predictions. Our measurement exploits a magnetic trap isolating the sample from perturbations and a magneto-optical trap as an amplifier converting each $^{3}P_{2}\ensuremath{\rightarrow}^{1}S_{0}$ decay event into millions of photons readily detected. The transition rate is determined to be $(4.87\ifmmode\pm\else\textpm\fi{}0.3)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}4}\text{ }\text{ }{\mathrm{s}}^{\ensuremath{-}1}$ corresponding to a $^{3}P_{2}$ lifetime of ${2050}_{\ensuremath{-}110}^{+140}$ sec. This value is in agreement with recent theoretical predictions, and to our knowledge the longest lifetime ever determined in a laboratory environment.

We present measurements of the isotope shift for the $(3s3p){}^{1}P\ensuremath{-}(3s3d){}^{1}D$ transitions at $881$ nm in Mg i. The three stable magnesium isotopes yielded a shift $^{24}\mathrm{Mg}$--$^{25}\mathrm{Mg}$ of $(1342\ifmmode\pm\else\textpm\fi{}20)$ MHz and $^{25}\mathrm{Mg}$--$^{26}\mathrm{Mg}$ of $(1175\ifmmode\pm\else\textpm\fi{}23)$ MHz. Measured shifts are consistent with recent relativistic many-body calculations of the mass effect.

We present the first experimental determination of the electric-dipole forbidden (3s3p)³P₂→(3s²)¹S₀ (M2) transition rate in ²⁴Mg and compare to state-of-the-art theoretical predictions. Our measurement exploits a magnetic trap isolating the sample from perturbations and a magneto-optical trap as an amplifier converting each ³P₂→¹S₀ decay event into millions of photons readily detected. The transition rate is determined to be (4.87 ± 0.3)×10⁻⁴ s⁻¹ corresponding to a ³P₂ lifetime of 2050(-110)(+140) sec. This value is in agreement with recent theoretical predictions, and to our knowledge the longest lifetime ever determined in a laboratory environment.

Variations in optical transmission of four types of hollow-core photonic bandgap fibers are measured as a function of laser frequency. These variations influence the potential accuracy of gas sensors based on molecular spectroscopy in HC-PBFs.

The current definition of the temperature unit kelvin is based on the triple point of water. The relative accuracy of about 2·10−7 of this definition is basically limited by the “purity“ of the water in the triple point cell. In order to meet future demands for temperature measurements, it is desireable to redefine the kelvin by fixing the value of the Boltzmann constant [1]. The current value for the Boltzmann constant (kB) has a relative uncertainty of 1.7·10−6, and this must be improved before redefining the temperature unit.

We demonstrate an accurate method for measuring the lifetime of long-lived metastable magnetic states using a magneto-optical trap (MOT). Through optical pumping, the metastable $(3s3p)\text{ }{^{3}P}_{1}$ level is populated in a standard MOT. During the optical pumping process, a fraction of the population is captured in the magnetic quadrupole field of the MOT. When the metastable atoms decay to the $(3{s}^{2})\text{ }{^{1}S}_{0}$ ground state they are recaptured into the MOT. In this system no alternative cascading transition is possible. The lifetime of the metastable level is measured directly as an exponential load time of the MOT. We have experimentally tested our method by measuring the lifetime of the $(3s3p)\text{ }{^{3}P}_{1}$ of $^{24}\text{M}\text{g}$. This lifetime has been measured numerous times previously, but with quite different results. Using our method we find the $(3s3p)\text{ }{^{3}P}_{1}$ lifetime to be $(4.4\ifmmode\pm\else\textpm\fi{}0.2)\text{ }\text{ms}$. Theoretical values point toward a lower value for the lifetime.

We demonstrate the observation of saturated absorption in several molecules in HC-PBFs. Characteristics of these molecular reference lines are discussed and the locking of fiber lasers to the molecular absorption lines is demonstrated.

We have applied the frequency-modulation (FM) technique in the 1.5 mum wavelength region to observe saturated absorption in ammonia in hollow-core photonic bandgap fibers (HC-PBFs). Previously blended lines have been resolved.

We report on saturated absorption in a hollow-core photonic band-gap fiber filled with 12C2H2 molecules. We find that slow molecules provide a major contribution to the signal in the limit of low optical power and low pressure where the signal deviates significantly from the usual Lorentzian line shape. In particular, we observe a linewidth reduction of about 3 times as compared to the transit-time limited linewidth.

We demonstrate that a setup for cavity enhanced optical frequency doubling can be used to determine the responsivity of a UV detector at the second harmonic wavelength. This determination relies only on relative power measurements and a known responsivity of an optical detector at the fundamental wavelength

To find reliable data of the incidence of different variations of the spine.Standardised radiographic examinations of 10,922 young, healthy pilot aspirants of the German air force were made. Radiographic examination included the whole spine in a.p. and lateral projection, the cervical spine in oblique projection and in a subunit of 5781 men the lumbar spine in oblique projection.The following incidences were found: mild habit scoliosis: 80.4%, structural scoliosis: 9%, severe thoracal kyphosis without severe lumbar lordosis: 5.1% and together with severe lumbar lordosis: 30.8%, mild forms of kyphosis of adolescence: 23.3%, severe forms: 2.1% and cuneiform deformation of vertebral body: 4.9%, sacralization: 7.8%, lumbarization: 5.9%, spondylolysis: 6.2%, spondylolisthesis: 4.3% and lumbar chondrosis: 2.1%. Chondrosis of the thoracal and cervical spine, osteochondrosis and coalescent vertebral bodies were found in less than 0.8% each.In only 2.6% were there no pathological findings. This shows importance of radiological spine examinations especially for industrial and preventive medicine.

Rectal endosonography is a reliable method for preoperative staging of rectal carcinoma [1]. The clinical value of this technique is perhaps even greater in postoperative management because some recurrences cannot be detected either by digital rectal examination or by rectoscopy [2-6]. Furthermore, with endosonography, biopsy can be performed under sonographic guidance. We report our preliminary experience with rectal endosonography and transrectal endosonographically guided biopsy of suspected recurrent lesions in five patients who had undergone prior resection of the rectum for carcinoma.

The Spatial Transformation of Sound Fields (STSF) technique permits a 3D sound field mapping based on a 2D scan measurement in the near field of a source. By measurement of the cross spectra between a set of references and the cross spectra from each scan position to each of the references, a principal component representation of the sound field is extracted which can be applied for near field holography and Helmholtz' integral equation calculations. Basically, this sound field representation includes only the part of the sound field, which is coherent with the reference signals. More precisely, only "views" of the independent parts of the sound field seen by the references are included. Therefore, provided the references do not pick up the background noise, the background noise will not be part of the sound field model processed by STSF. However, if the background noise is picked up by the reference transducers, it will become part of the model and cause errors in the calculations. In order to overcome this problem, the possibility of using a set of "exclude references" has been implemented in the STSF system. These references should pick up only the uncorrelated background noise to be suppressed in the model.

Histological studies of the auditory organ in patients with acquired hypothyroidism are scarce. Thus the aim of the present study was to examine the temporal bones and the brain is subjects with hypothyroidism. Four temporal bones and two brains from clinically and biochemically hypothyroid subjects were removed and evaluated by light microscopy determine to the morphological changes and deposition of neutral and acid glycosaminnoglycans. An audiogram from one of the patients showed a sensorineural hearing loss. Which could be ascribed to occupational noise exposure. The study revealed histological changes compatible with age and infectious disease. No accumulation of neutral or acid glycosaminoglycans could be demonstrated in the temporal bones, or in the brains.

The results of a survey are presented conerning the effectiveness of mass media publicity with the public. After oral contraceptives containing high levels of estrogen were prohibited in Denmark, a telephone survey of 23 doctors was taken to determine the fluctuation in demand for medical information from patients, and the reason for the fluctuation. The reasons were divided into 3 groups: 1) resulting from mass media publicity, 2) resulting from the unavailability of a particular contraceptive, and 3) other. 3 surveys were conducted of the frequency of demand for information on the high estrogen contraceptives, 1 for each of the 2 weeks after the prohibition and withdrawal of the contraceptives took place, and 1 1 month after the prohibition. 2-3% of the inquiries received by the doctors concerned the prohibited contraceptives, and half of these could be attributed directly to the mass media publicity. The number of requests in categories 1 and 2 dropped sharply in the 2nd and 3rd surveys, indicating that the effect of the mass meida publicity and the withdrawal of the contraceptive from the market had only a very immediate effect. It is also shown that the telephone can be used successfully to ascertain the effects of a short-term social phenomenon on the public.

Barium peritonitis secondary to perforation of the gut is an infrequent complication of radiological G-I tract examinations. It is thought to imply a high mortality rate. However, this conception seems to be based on data obtained during the early 1950's. More recent case reports and small series indicate a more favourable prognosis depending on effective antibiotics and successful maintenance of severily ill patients. The scant information concerning the fate of pediatric cases warranted presentation of the experience of 5 patients, who all survived. Our approach to treatment and the suggested use of barium studies, in particular barium enema, in obscure abdominal emergency cases are offered.

A case of partial and fluctuating cochlear hearing loss persisting one year after meningococcal meningitis is presented. Repeated audiometry after the recovery from the disease is recommended in all patients.