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1.
Faraday Discuss ; 239(0): 130-145, 2022 Oct 28.
Article in English | MEDLINE | ID: mdl-35843221

ABSTRACT

The interface formation and chemical and electronic structure of the (Cd,Zn)S:Ga/CuSbS2 thin-film solar cell heterojunction were studied using hard X-ray photoelectron spectroscopy (HAXPES) of the bare absorber and a buffer/absorber sample set for which the buffer thickness was varied between 1 and 50 nm. We find a heavily intermixed interface, involving Cu, Zn, and Cd as well as significant Ga and Cu profiles in the buffer. The valence band (VB) offset at the buffer/absorber interface was derived as (-1.3 ± 0.1) eV, which must be considered an upper bound as the Cu diffused into the buffer might form a Cu-derived VB maximum located closer to the Fermi level. The estimated conduction band minimum was 'cliff'-like; a situation made more severe considering the Cu-deficiency found for the CuSbS2 surface. The complex interface structure's effect on the performance of (Cd,Zn)S:Ga/CuSbS2-based solar cells and its limitation is discussed together with possible mitigation strategies.

2.
Phys Chem Chem Phys ; 21(24): 13207-13214, 2019 Jun 28.
Article in English | MEDLINE | ID: mdl-31179459

ABSTRACT

The local valence orbital structure of solid glycine, diglycine, and triglycine is studied using soft X-ray emission spectroscopy (XES), resonant inelastic soft X-ray scattering (RIXS) maps, and spectra calculations based on density-functional theory. Using a building block approach, the contributions of the different functional groups of the peptides are separated. Cuts through the RIXS maps furthermore allow monitoring selective excitations of the amino and peptide functional units, leading to a modification of the currently established assignment of spectral contributions. The results thus paint a new-and-improved picture of the peptide bond, enhance the understanding of larger molecules with peptide bonds, and simplify the investigation of such molecules in aqueous environment.


Subject(s)
Models, Chemical , Peptides/chemistry , Dynamic Light Scattering , Electrons , Glycine/chemistry , Glycylglycine/chemistry , Oligopeptides/chemistry , Quantum Theory , Water/chemistry , X-Ray Diffraction
3.
Phys Chem Chem Phys ; 20(12): 8302-8310, 2018 Mar 28.
Article in English | MEDLINE | ID: mdl-29532819

ABSTRACT

The occupied and unoccupied electronic structure of imidazole (C3N2H4) and imidazolium (C3N2H5+) in aqueous solutions is studied by X-ray emission spectroscopy (XES) and resonant inelastic soft X-ray scattering (RIXS). Both systems show distinct RIXS fingerprints with strong resonant effects. A comparison with calculated X-ray emission spectra of isolated imidazole and imidazolium suggests only a small influence of hydrogen bonding in the aqueous solution on the electronic structure of imidazole and imidazolium, and allows the attribution of specific spectral features to the non-equivalent nitrogen and carbon atoms in the molecules. In the case of nitrogen, this can also be achieved by site-selective resonant excitation. Furthermore, we find spectator shifts and symmetry selectivity in the RIXS spectra, as well as indications for rapid proton dynamics on the femtosecond timescale of the RIXS process, and derive the HOMO-LUMO gaps for the two molecules in aqueous solution.

4.
J Phys Chem A ; 120(14): 2260-7, 2016 Apr 14.
Article in English | MEDLINE | ID: mdl-27003748

ABSTRACT

The electronic structure of gas-phase methanol molecules (H3COH, H3COD, and D3COD) at atmospheric pressure was investigated using resonant inelastic soft X-ray scattering (RIXS) at the O K and C K edges. We observe strong changes of the relative emission intensities of all valence orbitals as a function of excitation energy, which can be related to the symmetries of the involved orbitals causing an angularly anisotropic RIXS intensity. Furthermore, all observed emission lines are subject to strong spectator shifts of up to -0.9 eV at the O K edge and up to -0.3 eV at the C K edge. At the lowest O K resonance, we find clear evidence for dissociation of the methanol molecule on the time scale of the RIXS process, which is illustrated by comparing X-ray emission spectra of regular and deuterated methanol.

5.
Phys Chem Chem Phys ; 17(40): 27145-53, 2015 Oct 28.
Article in English | MEDLINE | ID: mdl-26417728

ABSTRACT

To probe the influence of hydrogen bonding on the electronic structure of ammonia, gas phase and aqueous NH3 have been investigated using soft X-ray absorption (XAS), resonant inelastic soft X-ray scattering (RIXS), and electronic structure calculations including dynamical effects. Strong spectral differences in the XAS scans as well as in the RIXS spectra between gas phase and aqueous NH3 are attributed to orbital mixing with the water orbitals, dipole-dipole interactions, differences in vibronic coupling, and nuclear dynamics on the time-scale of the RIXS process. All of these effects are consequences of hydrogen bonding and the impact of the associated orbitals, demonstrating the power of XAS and RIXS as unique tools to study hydrogen bonding in liquids.

6.
Phys Chem Chem Phys ; 16(47): 26266-72, 2014 Dec 21.
Article in English | MEDLINE | ID: mdl-25363298

ABSTRACT

The interface between solid-phase crystallized phosphorous-doped polycrystalline silicon (poly-Si(n(+))) and aluminum-doped zinc oxide (ZnO:Al) was investigated using spatially resolved photoelectron emission microscopy. We find the accumulation of aluminum in the proximity of the interface. Based on a detailed photoemission line analysis, we also suggest the formation of an interface species. Silicon suboxide and/or dehydrated hemimorphite have been identified as likely candidates. For each scenario a detailed chemical reaction pathway is suggested. The chemical instability of the poly-Si(n(+))/ZnO:Al interface is explained by the fact that SiO2 is more stable than ZnO and/or that H2 is released from the initially deposited a-Si:H during the crystallization process. As a result, Zn (a deep acceptor in silicon) is "liberated" close to the silicon/zinc oxide interface presenting the inherent risk of forming deep defects in the silicon absorber. These could act as recombination centers and thus limit the performance of silicon/zinc oxide based solar cells. Based on this insight some recommendations with respect to solar cell design, material selection, and process parameters are given for further knowledge-based thin-film silicon device optimization.

7.
Chaos ; 24(4): 043142, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25554062

ABSTRACT

Pattern formation often occurs in spatially extended physical, biological, and chemical systems due to an instability of the homogeneous steady state. The type of the instability usually prescribes the resulting spatio-temporal patterns and their characteristic length scales. However, patterns resulting from the simultaneous occurrence of instabilities cannot be expected to be simple superposition of the patterns associated with the considered instabilities. To address this issue, we design two simple models composed by two asymmetrically coupled equations of non-conserved (Swift-Hohenberg equations) or conserved (Cahn-Hilliard equations) order parameters with different characteristic wave lengths. The patterns arising in these systems range from coexisting static patterns of different wavelengths to traveling waves. A linear stability analysis allows to derive a two parameter phase diagram for the studied models, in particular, revealing for the Swift-Hohenberg equations, a co-dimension two bifurcation point of Turing and wave instability and a region of coexistence of stationary and traveling patterns. The nonlinear dynamics of the coupled evolution equations is investigated by performing accurate numerical simulations. These reveal more complex patterns, ranging from traveling waves with embedded Turing patterns domains to spatio-temporal chaos, and a wide hysteretic region, where waves or Turing patterns coexist. For the coupled Cahn-Hilliard equations the presence of a weak coupling is sufficient to arrest the coarsening process and to lead to the emergence of purely periodic patterns. The final states are characterized by domains with a characteristic length, which diverges logarithmically with the coupling amplitude.


Subject(s)
Feedback , Models, Theoretical , Nonlinear Dynamics , Oscillometry/methods , Spatio-Temporal Analysis , Computer Simulation
8.
J Chem Phys ; 138(3): 034306, 2013 Jan 21.
Article in English | MEDLINE | ID: mdl-23343275

ABSTRACT

Resonant inelastic soft x-ray scattering (RIXS) was used to study the electronic structure of solid cysteine films. A RIXS map approach, i.e., plotting the x-ray emission intensity as a function of excitation and emission energy, allows us to separate the contributions of the three chemically non-equivalent carbon atoms in cysteine. In particular, we can identify orbitals localized near the photoexcited atoms, as well as orbitals that are delocalized over the entire molecule.


Subject(s)
Carbon/chemistry , Cysteine/chemistry , Scattering, Radiation , X-Rays
9.
Acta Neurol Scand ; 125(1): 8-15, 2012 Jan.
Article in English | MEDLINE | ID: mdl-21883097

ABSTRACT

OBJECTIVES: To evaluate, for the first time in patients with epilepsy, the tolerability and safety of escalating doses of oral perampanel, a novel, selective, non-competitive AMPA antagonist, as adjunctive therapy for refractory partial-onset seizures. MATERIALS AND METHODS: Two consecutive, randomized, double-blind, dose-escalation studies recruited adults (18-70 years) with uncontrolled partial-onset seizures receiving one to three concomitant antiepileptic drugs. In study 206, patients were treated for 12 weeks (8-week dose-titration, 4-week dose-maintenance) with placebo or perampanel (up to 4 mg/day, dosed once- or twice-daily). In study 208, patients received placebo or perampanel once-daily (up to 12 mg) for 16 weeks (12-week titration, 4-week maintenance). RESULTS: Overall, 153 patients were randomized into study 206 (perampanel twice-daily, n = 51; perampanel once-daily, n = 51; placebo, n = 51). Study 208 included 48 patients (perampanel once-daily, n = 38; placebo, n = 10). The highest dose in study 206 - 4 mg/day - was well tolerated, with similar proportions of patients tolerating once-daily (82.4%) and twice-daily (82.4%) perampanel and placebo (82.4%) treatments. In study 208 most patients tolerated doses of ≥ 6 mg perampanel once-daily in a Kaplan-Meier analysis. In both studies, the most common adverse events were CNS-related; most were of mild/moderate severity. CONCLUSIONS: Perampanel was well tolerated across doses of 4-12 mg/day. The studies showed preliminary evidence of efficacy and identified doses to be evaluated in larger clinical studies.


Subject(s)
Epilepsies, Partial/drug therapy , Pyridones/adverse effects , Adolescent , Adult , Aged , Anticonvulsants/adverse effects , Anticonvulsants/therapeutic use , Dose-Response Relationship, Drug , Double-Blind Method , Drug Administration Schedule , Female , Humans , Male , Middle Aged , Nitriles , Pyridones/administration & dosage , Pyridones/therapeutic use , Treatment Outcome
10.
Acta Neurol Scand ; 126(4): 263-9, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22913800

ABSTRACT

OBJECTIVES: Evaluate interim long-term tolerability, safety and efficacy of adjunctive perampanel, a novel α-amino-3-hydroxy-5-methyl-5-isoxazolepropionic acid (AMPA)-receptor antagonist, in patients with refractory partial-onset seizures. MATERIALS AND METHODS: Study 207, an open-label extension (OLE) study (ClinicalTrials.gov identifier: NCT00368472), enrolled patients (18-70 years) who completed one of two randomized, placebo-controlled, dose-escalation Phase II studies. The OLE Treatment Phase comprised a 12-week Titration Period (2 mg increments of perampanel every 2 weeks to 12 mg/day, maximum) and a Maintenance Period, during which patients continued treatment up to a planned maximum of 424 weeks (~8 years). Interim analysis data cut-off date was 1 December, 2010. RESULTS: Of 180 patients completing the Phase II studies, 138 enrolled in study 207. At the time of interim analyses (approximately 4 years after study start), over a third (n = 53, 38.4%) remained on perampanel; 41.3% (n = 57) of patients had >3 years of exposure; and 13.0% (n = 18) had at least 4 years' exposure. Mean ± standard deviation (SD) duration of exposure was 116 ± 75 weeks and mean ± SD dose during the OLE Maintenance Period was 7.3 ± 3.3 mg. No new safety signals emerged with long-term treatment. Consistent with previous studies, the most common treatment-emergent adverse events were as follows: dizziness, headache and somnolence. Overall median (range) per cent change from baseline in seizure frequency per 28 days during open-label treatment was -31.5% (-99.2 to 512.2). CONCLUSIONS: Long-term - up to 4 years - adjunctive perampanel had a favourable tolerability profile in patients with refractory partial-onset seizures. Improvements in seizure control were maintained with long-term treatment.


Subject(s)
Anticonvulsants/therapeutic use , Epilepsy/drug therapy , Pyridones/therapeutic use , Adolescent , Adult , Aged , Dose-Response Relationship, Drug , Double-Blind Method , Drug Administration Schedule , Drug Therapy, Combination , Female , Humans , Longitudinal Studies , Male , Middle Aged , Nitriles , Treatment Outcome , Young Adult
11.
Appl Opt ; 51(30): 7384-94, 2012 Oct 20.
Article in English | MEDLINE | ID: mdl-23089796

ABSTRACT

We investigate the impact of line-edge and line-width roughness (LER, LWR) on the measured diffraction intensities in angular resolved extreme ultraviolet (EUV) scatterometry for a periodic line-space structure designed for EUV lithography. LER and LWR with typical amplitudes of a few nanometers were previously neglected in the course of the profile reconstruction. The two-dimensional (2D) rigorous numerical simulations of the diffraction process for periodic structures are carried out with the finite element method providing a numerical solution of the 2D Helmholtz equation. To model roughness, multiple calculations are performed for domains with large periods, containing many pairs of line and space with stochastically chosen line and space widths. A systematic decrease of the mean efficiencies for higher diffraction orders along with increasing variances is observed and established for different degrees of roughness. In particular, we obtain simple analytical expressions for the bias in the mean efficiencies and the additional uncertainty contribution stemming from the presence of LER and/or LWR. As a consequence this bias can easily be included into the reconstruction model to provide accurate values for the evaluated profile parameters. We resolve the sensitivity of the reconstruction from this bias by using simulated data with LER/LWR perturbed efficiencies for multiple reconstructions. If the scattering efficiencies are bias-corrected, significant improvements are found in the reconstructed bottom and top widths toward the nominal values.

12.
Pathologe ; 33(5): 459-62, 2012 Sep.
Article in German | MEDLINE | ID: mdl-22562701

ABSTRACT

Trichilemmal cysts can occur as multiple scalp lesions and may have a familial history. Metaplastic ossification, as seen in several traumatic, inflammatory or neoplastic conditions, however, seems to be an exceedingly rare event in trichilemmal cysts and might be associated with previous rupture.


Subject(s)
Follicular Cyst/pathology , Follicular Cyst/surgery , Hair Diseases/pathology , Hair Diseases/surgery , Ossification, Heterotopic/pathology , Ossification, Heterotopic/surgery , Adult , Diagnosis, Differential , Epidermal Cyst , Female , Follicular Cyst/genetics , Hair Diseases/genetics , Humans , Metaplasia , Rupture, Spontaneous , Surgical Flaps
13.
Mult Scler Relat Disord ; 67: 104177, 2022 Nov.
Article in English | MEDLINE | ID: mdl-36130459

ABSTRACT

BACKGROUND: Serum neurofilaments (sNfs), especially the most investigated serum neurofilament light chain (sNfL), are promising biomarkers in multiple sclerosis (MS). However, their clinical utility is still limited, given the availability and costs of accessible analytical methods. The gold standard for the detection of sNfs is represented by the single molecule arrays (SIMOA). Recently, a high sensitivity enzyme-linked immunosorbent assay (hsELISA) has also been introduced. The objective of the study was to compare both assays for the determination of sNfL and neurofilament heavy chain (sNfH) concentrations in a defined MS cohort. The second objective was to identify contributing factors to sNfs concentrations determined by hsELISA. METHODS: Serum samples were collected from MS patients attending the MS Centre, University Hospital Ostrava, Czech Republic. The levels of sNfs were detected using SIMOA and hsELISA assays. RESULTS: The Spearman's rank correlation coefficient between the sNfL SIMOA and sNfL hsELISA and between the sNfH SIMOA and sNfH hsELISA was moderate rs= 0.543 (p = 0.001) and rs= 0.583 (p = 0.001), respectively. The Passing-Bablok regression analysis demonstrated bias between both methods. Equally significant bias between the methods was confirmed by the Bland-Altman plots. Furthermore, confounding factors affecting the sNfL levels were glomerular filtration rate (eGFR; 95% CI -2.34 to -0.04) and sex (95% CI -2.38 to -0.10). The sNfH levels were affected by age (95% CI 0.01 to 0.07), eGFR (95% CI -2.45 to -0.02), body mass index (BMI; 95% CI -0.31 to -0.05), and blood volume (95% CI 0.69 to 3.35). CONCLUSION: This analytical study showed significant differences between hsELISA and SIMOA methods, especially for the sNfH concentrations. We identified confounding factors for sNfs levels determined by hsELISA. The sNfs levels were influenced by renal function and sex, whilst sNfH levels were affected by age, BMI, and total blood volume.


Subject(s)
Intermediate Filaments , Multiple Sclerosis , Humans , Multiple Sclerosis/diagnosis , Biomarkers , Enzyme-Linked Immunosorbent Assay , Czech Republic
14.
Sci Rep ; 12(1): 18374, 2022 11 01.
Article in English | MEDLINE | ID: mdl-36319704

ABSTRACT

An evidence-based treatment for a Multiple Sclerosis (MS) relapse is an intravenous administration of 3-5 g of Methylprednisolone. In case of insufficient effect or corticosteroids intolerance, the therapeutic plasma exchange (TPE) is indicated. To assess the clinical effect of TPE in treatment of relapse in patients with relapsing-remitting MS (RRMS), we enrolled 155 patients meeting the following criteria (study period: January 2011 to February 2021): (1) age > 18, (2) RRMS according to the McDonald´s 2017 criteria, (3) MS relapse and insufficient effect of corticosteroids/corticosteroids intolerance, (4) baseline EDSS < 8. Exclusion criteria: (1) progressive form of disease, (2) history of previous TPE. Following parameters were monitored: EDSS changes (before and after corticosteroid treatment, before and after TPE; EDSS after TPE was assessed at the next clinical follow-up at the MS Center), and improvement of EDSS according to the number of procedures and baseline severity of relapse. 115 females (74%) and 40 males (26%) were included. The median age was 41 years (IQR 33-47)-131 patients underwent the pulse corticosteroids treatment and TPE, while 24 patients underwent only TPE without any previous corticosteroid treatment. Median baseline EDSS was 4.5 (IQR 3.5-5.5), median EDSS after finishing steroids was 4.5 (IQR 4.0-5.5). EDSS prior to the TPE was 4.5 (IQR 4-6), EDSS after TPE was 4.5 (IQR 3.5-5.5). We observed a significant improvement in the EDSS after TPE (p < 0.001). Sex differences were seen in TPE effectiveness, with median improvement of EDSS in females being -0.5 (IQR 1-0) and in males being 0 (IQR -0.5 to 0), p = 0.048. There was no difference in EDSS improvement by age category: 18-30 years, 31-40 years, 41-50 years, > 50 (p = 0.94), nor by total TPE count (p = 0.91). In this retrospective study of patients with an aggressive relapse and insufficient effect of intravenous corticosteroid treatment, a significant effect of TPE on EDSS improvement was observed. There was no significant difference in TPE effectivity according to the number of procedures, age, nor severity of a relapse. In this cohort, TPE was more effective in females.


Subject(s)
Multiple Sclerosis, Relapsing-Remitting , Multiple Sclerosis , Humans , Female , Male , Adult , Middle Aged , Adolescent , Young Adult , Multiple Sclerosis/drug therapy , Plasma Exchange/methods , Retrospective Studies , Multiple Sclerosis, Relapsing-Remitting/drug therapy , Recurrence , Adrenal Cortex Hormones/therapeutic use
15.
J Chem Phys ; 135(10): 104705, 2011 Sep 14.
Article in English | MEDLINE | ID: mdl-21932916

ABSTRACT

We have employed a unique spectroscopic approach, a resonant inelastic soft x-ray scattering (RIXS) map, to identify and separate electron-hole correlation effects in core-level spectroscopy. With this approach, we are able to derive a comprehensive picture of the electronic structure, separating ground state properties (such as the HOMO-LUMO separation) from excited state properties (such as the C 1s core-exciton binding energy of C(60)). In particular, our approach allows us to determine the difference between core- and valence exciton binding energies in C(60) [0.5 (±0.2) eV]. Furthermore, the RIXS map gives detailed insight into the symmetries of the intermediate and final states of the RIXS process.

16.
Med Vet Entomol ; 25(1): 84-93, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21077924

ABSTRACT

Identifying morphologically similar triatomine species is key to Chagas' disease vector control and surveillance, but remains challenging when only qualitative phenotypic data are available. We investigated whether morphometric and ecological variation can provide additional criteria for species delimitation by combining geometric morphometrics and ecological niche modelling to characterize two near-sibling triatomine species, Triatoma sordida and Triatoma garciabesi (Reduviidae: Triatominae). We analysed size and shape variation in 231 wings and 123 heads from one T. garciabesi and three T. sordida populations. Predicted distribution maps (21 climatic variables, 324 vector occurrence points) were produced using the Maxent method. Multivariate analyses summarized morphological and ecological variation. Wings and heads of T. sordida were significantly larger and more elongated than those of T. garciabesi. Discriminant analyses separated the species, with a partial overlap between Argentinean populations. The predicted distribution of T. garciabesi included northwest Argentina (mainly arid Chaco), whereas that of T. sordida included northeast Argentina (humid Chaco) and the Brazilian Cerrado and Caatinga ecoregions. Clear ecological niche differences were observed, with T. garciabesi occupying colder and drier areas than T. sordida. Our results show how morphometric variation and niche divergence can be used to enhance operational criteria for the delimitation of phenotypically similar triatomine species.


Subject(s)
Models, Biological , Triatoma/anatomy & histology , Triatoma/classification , Animals , Argentina , Brazil , Chagas Disease/transmission , Ecosystem , Insect Vectors/anatomy & histology , Insect Vectors/classification , Insect Vectors/physiology , Triatoma/physiology
17.
Z Gerontol Geriatr ; 44(1): 13-8, 2011 Feb.
Article in German | MEDLINE | ID: mdl-21359631

ABSTRACT

In nursing care for people with dementia, biographical work is a popular concept. In the literature and practice, many different viewpoints of the way biographical work can/should be promoted exist. In the DEMIAN concept, a nursing concept to promote emotional well-being for people with dementia, it is also of major significance. This article gives an overview of the importance of biographical work in caring for people with dementia. In particular, the role and arrangement of biographical work in the DEMIAN concept are described. Within the anamnesis of the DEMIAN concept, meaningful themes are identified in conversations with different participants (person with dementia, reference persons, and care workers) and through observations. From these findings, specific interventions, aimed at supporting emotional well-being of people with dementia, are derived and integrated into everyday nursing care to promote emotional well-being. The potential of the DEMIAN nursing concept are discussed and further possibilities are highlighted.


Subject(s)
Biographies as Topic , Dementia/nursing , Geriatric Nursing/methods , Hospitalization , Long-Term Care/methods , Aged , Feasibility Studies , Female , Germany , Humans , Male
18.
Acta Chim Slov ; 68(3): 521-531, 2021 Sep.
Article in English | MEDLINE | ID: mdl-34897546

ABSTRACT

Thiamethoxam (Thmx) is a globally used neonicotinoid pesticide contaminated in freshwater ecosystems with residues detected in fishery products. Astacus leptodactylus is a popular freshwater crustacean that is cultivated and exported in many countries. In this study, we investigated the acute toxic effects of Thmx on A. leptodactylus using various biomarkers (acetylcholinesterase, carboxylesterase, glutathione S-transferase, glutathione, superoxide dismutase, glutathione peroxidase, glutathione reductase, and adenosinetriphosphatases). The 96-h LC50 value of Thmx was calculated as 8.95 mg active ingredient L-1. As the dose of Thmx increased, oxidative stress was induced by the inhibition/activation of antioxidant enzymes, while the activities of acetylcholinesterase, carboxylesterase and adenosinetriphosphatases were inhibited. As a result, it can be said that Thmx has highly toxic effects on crayfish, therefore they are under threat in the areas where this pesticide is used.


Subject(s)
Acetylcholinesterase/metabolism , Adenosine Triphosphatases/metabolism , Biomarkers/metabolism , Insecticides/toxicity , Oxidative Stress/drug effects , Thiamethoxam/toxicity , Animals , Astacoidea , Carboxylesterase/metabolism , Cholinesterase Inhibitors/toxicity , Water Pollutants, Chemical/toxicity
19.
Opt Express ; 18(10): 10177-87, 2010 May 10.
Article in English | MEDLINE | ID: mdl-20588872

ABSTRACT

We report on the development of a compact, easy-to-use terahertz radiation source, which combines a quantum-cascade laser (QCL) operating at 3.1 THz with a compact, low-input-power Stirling cooler. The QCL, which is based on a two-miniband design, has been developed for high output and low electrical pump power. The amount of generated heat complies with the nominal cooling capacity of the Stirling cooler of 7 W at 65 K with 240 W of electrical input power. Special care has been taken to achieve a good thermal coupling between the QCL and the cold finger of the cooler. The whole system weighs less than 15 kg including the cooler and power supplies. The maximum output power is 8 mW at 3.1 THz. With an appropriate optical beam shaping, the emission profile of the laser is fundamental Gaussian. The applicability of the system is demonstrated by imaging and molecular-spectroscopy experiments.


Subject(s)
Air Conditioning/instrumentation , Lasers , Lighting/instrumentation , Computer-Aided Design , Energy Transfer , Equipment Design , Equipment Failure Analysis , Miniaturization , Terahertz Radiation
20.
Horm Res ; 72(5): 302-9, 2009.
Article in English | MEDLINE | ID: mdl-19844116

ABSTRACT

BACKGROUND/AIMS: Mutations in the HESX1 gene are associated with a broad spectrum of phenotypes: septo-optic dysplasia, midline defects, pituitary abnormalities with consequent hypopituitarism, isolated growth hormone (GH) deficiency or combined pituitary hormone deficiencies (CPHD). This study examined the prevalence of mutations in the HESX1 gene in patients with CPHD. PATIENTS/METHODS: Sixty patients with sporadic CPHD without septo-optic dysplasia were screened for mutations in HESX1. RESULTS: Three patients were found to be heterozygous for the same Asn125Ser variant in the HESX1 gene. In all 3, panhypopituitarism was presented in the neonatal period, manifested by severe hypoglycemia and neonatal jaundice in 2 patients and respiratory distress in 1. Remarkable findings from physical examination included coarse face; prominent, large, low-set ears; and skeletal abnormalities. Magnetic resonance imaging, performed in 2 patients, revealed a hypoplastic anterior and ectopic posterior pituitary without other midline anomalies. Despite persistent GH deficiency and undetectable levels of insulin-like growth factor 1, all patients had normal linear growth along the 10-25th percentile without GH therapy. CONCLUSION: The present study expands the clinical picture of HESX1 mutations by demonstrating that patients heterozygous for Asn125Ser may have a severe endocrinologic and neuroradiologic phenotype and similar dysmorphic features appearing very early in life.


Subject(s)
Facial Asymmetry/complications , Growth Disorders/complications , Growth/physiology , Pituitary Diseases/complications , Pituitary Hormones/deficiency , Adolescent , DNA Mutational Analysis , Facial Asymmetry/genetics , Growth Disorders/genetics , Homeodomain Proteins/genetics , Human Growth Hormone/deficiency , Humans , Male , Middle Aged , Pituitary Diseases/genetics , Pituitary Diseases/physiopathology
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