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We report on the preparation, structure and scintillation properties of single crystal cesium hafnium chloride bromide (Cs2HfCl4Br2 or CHCB). The crystals were grown using a vertical Bridgman technique process. Single crystal X-ray diffraction showed that the as grown CHCB crystal structure was isostructural to Cs2HfCl6 crystals exhibiting the cubic K2PtCl6 –type crystal structure. The Cs2HfCl6−x - Cs2HfBrx system is a solid solution with the lattice parameter of Cs2HfCl6−xBrx increasing linearly with x in the range 0

The loess-paleosol profiles at Krems in central Europe (Lower Austria) are well known for the impressive output of Upper Palaeolithic remains as well as for their paleoclimate potential as terrestrial archives. Previous high-resolution sedimentological and environmental magnetic results documented a rather complex sedimentological setting at Krems-Wachtberg, an Early Gravettian site. The site has been previously dated by radiocarbon as well as luminescence methods. Here, optically stimulated luminescence dating (OSL) methods and sedimentological analyses are reported for new profiles previously not investigated. Continuous wave luminescence (CW-OSL) has been performed on 16 samples on fine (4-11 μm) and coarse (63-90 μm) quartz grains. Despite extensive sample preparation the quartz extracts proved to be highly contaminated with other minerals. The application of standard single aliquot regenerative (SAR) protocol intrinsic rigour tests (recycling, IR depletion and recuperation) resulted in almost half of the analysed aliquots being rejected. Albeit improving the precision of the equivalent doses, the application of these rejection criteria did not result in significantly different average values. Pulsed OSL (POSL) has been further employed in order to better separate quartz OSL signals, but resulted in no significant change in the determined equivalent doses. Obtaining a higher accuracy and precision for the chronology of the Krems-Wachtberg site using currently available luminescence dating methods remains a daunting task, despite the archaeological and paleoenvironmental significance of the site.

Here we investigate the timing of the last glacial loess (L1) - Holocene soil (S0) transition recorded in loesspaleosol sequences from SE Europe (Ukraine, Romania, Serbia) by applying comparative luminescence dating techniques on quartz and feldspars. Equivalent dose measurements were carried out using the single-aliquot regenerative-dose (SAR) protocol on silt (4–11 μm) and sand-sized (63–90 μm and coarser fraction when available) quartz. Feldspar infrared stimulated luminescence (IRSL) emitted by 4–11 μm polymineral grains was measured using the post IR-IRSL290 technique. The paleoenvironmental transition from the last glacial loess to the current interglacial soil was characterized using magnetic susceptibility and its frequency dependence. SAR-OSL dating of 4–11 μm, 63–90 μm and 90–125 μm quartz provided consistent ages in the loess-paleosol sites investigated, while the post-IR IRSL290 protocol proved unreliable for dating such young samples. Based on these ages and the threshold of the magnetic signal enhancement the onset of soil formation has been placed around 16.6 ± 1.1 ka at Roxolany (Ukraine), 13.5 ± 0.9 ka at Mošorin (Serbia) and between 17.6 ± 1.4 ka and 12.4 ± 1.0 ka at Râmnicu Sărat (Romania). The trend observed in the magnetic parameters reflects the intensity of pedogenesis induced by regional climate amelioration during the Late Glacial, but the onset of magnetic susceptibility enhancement precedes the stratigraphic boundary of Pleistocene-Holocene dated at 11.7 ka in ice core records. Thus, magnetic susceptibility indicates a gradual increase in pedogenesis after Termination 1 (∼17 ka in the North Atlantic) at the sampling sites. Based on current data, it is not possible to define a synchronous threshold of change for all sections. However, the trend in the magnetic susceptibility data closely reflects the gradual transition from Last Glacial Maximum (LGM) towards the Holocene, with the onset of humus accumulation (A1 horizon) possibly linked to the prevalence of full interglacial conditions.

The loess-paleosol archive from Mircea Vodă (Romania) represents one of the most studied sections in Europe. We are applying here the current state of the art luminescence dating protocols for revisiting the chronology of this section. Analysis were performed on fine (4&ndash, 11 &micro, m) and coarse (63&ndash, 90 &micro, m) quartz extracts using the single aliquot regenerative (SAR) optically stimulated luminescence (OSL) dating protocol. Laboratory generated SAR dose response curves in the high dose range (5 kGy for fine quartz and 2 kGy for coarse quartz) were investigated by employing a test dose of either 17 or 170 Gy. The results confirm the previously reported different saturation characteristics of the two quartz fractions, with no evident dependency of the equivalent dose (De) on the size of the test dose. The OSL SAR ages are discussed and compared to the previously obtained results on quartz and feldspars. The previous reports regarding the chronological discrepancy between the two quartz fractions are confirmed. However, while previous investigations on other sites concluded that this discrepancy appears only above equivalent doses of about 100 Gy, here fine grain quartz ages underestimate coarse quartz ages starting with equivalent doses as low as around 50 Gy.

The internal contamination (radio-purity) of a cesium hafnium chloride (Cs 2 HfCl 6 ) crystal scintillator and its starting material (CsCl, HfCl 4 initial and after 3-fold static sublimation purification) was studied by HR-ICP-MS and with an ultra-low-background high purity germanium (ULB-HPGe) detector deep underground. This study was conducted for the purpose of assessing the feasibility of using CHC as a potential detector to the search for rare α decay occurring in Hafnium isotopes. Despite the low radio-purity of starting material, the resulting analysis concluded that the grown CHC crystal is free of nuclides of the U/Th natural decay chain. Only a limit was set on their activities to a few mBq/kg. However, the crystal was found to contain artificial and cosmogenic radionuclides: 137 Cs at 0.8 Bq/kg, 132 Cs at 25 mBq/kg, 134 Cs at 52 mBq/kg and 181 Hf at 14 mBq/kg.

The results of investigation into cesium hafnium chloride (Cs 2 HfCl 6 ) scintillating crystals as a promising detector to search for rare nuclear processes occurring in Hf isotopes is reported. The light output, quenching factor, and pulse-shape characteristics have been investigated at room temperature. The scintillation response of the crystal induced by α -particles and γ -quanta were studied to determine possibility of particle discrimination. Using the optimal filter method we obtained clear separation between signals with a factor of merit (FOM) = 9.3. This indicates that we are able to fully separate signals originating from α -particles and γ -quanta. Similar fruitful discrimination power was obtained by applying the mean time method (FOM = 7) and charge integration method (FOM = 7.5). The quenching factor for collimated 4 MeV α -particles is found to be 0.36, showing that α -particles generate more than a third of the light compared to γ -quanta at the same energy.

Resume Introduction Devant un globe urinaire febrile, lorsqu’une cause infectieuse ou obstructive est eliminee, l’IRM medullaire semble indispensable. Nous rapportons une observation d’encephalomyelite aigue disseminee (ADEM) supposee, d’origine post-infectieuse a Campylobacter , avec un tropisme essentiellement medullaire de l’atteinte du systeme nerveux central. Observation Un homme de 32 ans, sans antecedent, etait hospitalise pour globe urinaire febrile. Des diarrhees etaient retrouvees a l’interrogatoire 3 jours auparavant. L’evolution se compliquait d’une tetraparesie predominante aux membres inferieurs. L’IRM cerebro-medullaire objectivait une myelite thoracique. Un traitement par bolus de corticoides intraveineux durant 5 jours permettait une amelioration quasi complete des troubles moteurs et sphincteriens. La coproculture isolait un Campylobacter sp . Le diagnostic retenu etait celui d’une ADEM post-infectieuse bacterienne. Conclusion La clinique et l’IRM medullaire permettent de suspecter l’encephalomyelite aigue disseminee. Cette hypothese implique de rechercher activement un evenement infectieux ou une vaccination precedant les signes cliniques.

Strontium iodide (SrI 2 ), an important new scintillator crystal having a high light yield and excellent energy resolution, was grown for the first time by the edge-defined film-fed (EFG) growth method. Using high purity starting materials and floating dies made of graphite, fused quartz or AlN, large cylindrical, planar or square cross-section single crystals (12–15 mm across and >7 cm long) were produced at growth rates up to 15 mm/h, significantly faster than the current Bridgman growth technology. Details on the equipment used to grow this deliquescent material and on its growth behavior are given along with some discussion of crystalline quality.

Introduction Nous rapportons 2 cas de patientes ayant presente, quelques jours apres une infection ORL streptococcique, un tableau clinique meconnu, l’acrovesiculopustulose (AVP). Le tableau clinique etait toutefois plus bruyant qu’une simple eruption. Observation Cas clinique no 1 : une patiente de 51 ans, suivie pour une gammapathie monoclonale de signification indeterminee stable depuis des annees, est hospitalisee pour douleurs articulaires et eruption. Quatre jours apres une angine streptococcique traitee par cefuroxime et prednisolone, elle presente des arthralgies de rythme inflammatoire, des epaules, coudes, hanches, genoux et articulations des mains ainsi qu’une eruption palmoplantaire. Il s’agit de vesicules et de pustules enchâssees, et peu inflammatoires, qui evoluent en plusieurs poussees. La patiente se plaint aussi d’importantes sueurs nocturnes. La CRP est a 44 mg/L et les ASLO a 297 (N Cas clinique no 2 : une patiente âgee de 57 ans est hospitalisee pour des arthralgies asymetriques d’horaire inflammatoire touchant le poignet droit, la cheville gauche, les MCP gauches, le rachis dorsal, accompagnees d’une eruption vesiculeuse et pustuleuse des paumes. On note un important syndrome inflammatoire avec une CRP a 105 mg/L. Ce tableau survient 6 jours apres une angine traitee par cefuroxime. La biopsie cutanee met en evidence de nombreux polynucleaires neutrophiles de siege intra epidermique, et egalement une vesicule, et le derme sous-jacent est le siege d’un infiltrat inflammatoire modere polymorphe. Le bilan infectieux est negatif, (ASLO legerement augmentees), le bilan des rhumatismes inflammatoires egalement. L’IRM du rachis etait normale. Les lesions cutanees disparaissent sous dermocorticoides mais les arthralgies inflammatoires persistent, necessitant (AINS peu efficaces) de petites doses de corticoides par voie orale a doses rapidement degressives. La patiente presente une nouvelle poussee cutanee 8 semaines apres, suite a la realisation du vaccin DTP, accompagnee d’une recidive d’arthralgies touchant les memes articulations, rapidement regressive. Discussion L’AVP est un tableau clinique decrit depuis longtemps [1] , [2] mais peu connu. La physiopathologie est incertaine : reaction psoriasiforme au stimulus bacterien ? Forme localisee de psoriasis (quoique l’eruption puisse dans de rares cas etre disseminee) ? Le tableau associe une infection ORL prealable, un tableau d’installation rapide sur 24–48 h, de nombreuses pustules palmoplantaires de moins de 1 cm qui peuvent s’etendre sur la face dorsale des mains et des pieds voire sur l’ensemble du corps, et une evolution rapidement favorable en 2–3 semaines. L’hypothese d’une toxidermie parait peu probable, bien qu’une antibiotherapie soit frequemment administree dans ce contexte. Le tableau de nos patientes est coherent avec la description mais s’y ajoutent les arthralgies. Dans ce contexte, il est important de verifier qu’il ne s’agit pas d’une forme debutante de SAPHO, dont l’eruption palmoplantaire est identique, mais la chronologie post-streptococcique est toutefois rassurante. Les anglo-saxons, quant a eux, appellent l’AVP la pustulose palmoplantaire (PPP) qui appartiendrait aux psoriasis pustuleux, et qui pourrait preceder ou etre associee au psoriasis vulgaris. Il semble toutefois que l’amygdalectomie serait benefique dans la prise en charge de ces PPP… Conclusion Une eruption palmoplantaire vesiculopustuleuse doit faire rechercher une infection ORL streptococcique recente. Les 2 cas exposes ici entrent dans la definition de l’AVP mais sont notables par l’association d’arthralgies qui ne semblent pas connues comme faisant partie du tableau.

Lithium containing semiconductor-grade chalcogenide single crystals were grown using the vertical Bridgman method. The source material was synthesized from elementary precursors in two steps, (i) preparing the metal alloy LiIn or LiGa, and (ii) reaction with chalcogen – Se or Te. In a number of experiments, enriched 6 Li isotope was used for synthesis and growth. The composition and structure of the synthesized materials was verified using powder X-Ray diffraction. The energy band gaps of the crystals were determined using optical absorption measurements. The resistivity of LiInSe 2 and LiGaSe 2 , obtained using current–voltage measurements is on the order of 10 8 –10 11 Ω cm. Photoconductivity measurement of a yellow LiInSe 2 sample showed a peak in the photocurrent around 445 nm. Nuclear radiation detectors were fabricated from single crystal wafers and the responses to alpha particles, neutrons and gammas were measured and presented. It suggests that this material is a promising candidate for neutron detection applications.

Introduction Il existe peu d’etudes concernant plus specifiquement les caracteristiques des myopathies auto-immunes chez les individus âges. Nous avons etudie les caracteristiques des myopathies inflammatoires idiopathiques chez les sujets âges de plus de 70 ans. Patients et methodes Les donnees sont recueillies dans la base des donnees du Reseau Myosite est sur la periode 1991–2015. Nous avons pu identifier 43 patients âges de 70 ans ou plus au moment du diagnostic de myopathie inflammatoire, apres avoir exclu les patients ayant un diagnostic de myopathie a inclusions. Les parametres renseignes sont l’âge au diagnostic, le sexe, le type de myopathie inflammatoire, le delai jusqu’au diagnostic, les signes generaux, les signes musculaires et extra-musculaires, les caracteristiques biologiques (CPK, CRP, NFS, ACAN, anticorps specifiques des myosites, anticorps associes aux myosites), les maladies auto-immunes et les cancers associees, l’EMG, la biopsie musculaire et la therapeutique. Resultats Parmi les 43 patients âges nous avons identifie 12 hommes et 31 femmes, H/F = 0,38. L’âge moyen etait de 78,5 ans, extremes entre 70 et 87 ans, mais la moitie de patients ont moins de 75 ans. Nous avons pu identifier 13 myosites de chevauchement (les plus frequentes) dont 6 patients ont un tableau de syndrome des anti-synthetases, 9 myopathies necrosantes auto-immunes, 8 myosites associees aux cancers, 7 dermatomyosites et 6 polymyosites (la plus rare entite). Le delai diagnostique est de 27 mois en moyenne, allant de 1 mois a 53 mois entre le debut des symptomes et le moment du diagnostic. Quatre-vingt-dix pour cent des patients ont des symptomes musculaires : faiblesse musculaire proximale des membres inferieurs et/ou superieurs et myalgies. Des signes extra-musculaires sont presents chez 3/4 des patients, une atteinte cutanee frequemment. Un phenomene de Raynaud est present chez 6 patients, en general des patients ayant une myosite de chevauchement associant une sclerodermie. Deux tiers de patients ont des signes generaux. L’atteinte pulmonaire, sous la forme d’une pneumopathie interstitielle et l’atteinte articulaire sont presentes chez environ 25 % des patients. Trente-deux patients (74,4 %) ont des CPK elevees, valeurs allant de 250 UI/L a 12 000 UI/L, en moyenne entre 1000 et 2000 UI/L, mais presque 25 % des patients ont des CPK bien plus basses (500–1000 UI/L) ou meme normales. Les valeurs des CPK les plus hautes sont notees chez les patients ayant une MNAI. Vingt-huit patients (65 %) ont des anticorps antinucleaires et 12 patients (28 %) ont des « auto-anticorps specifiques des myosites », dont l’anti-Jo-1 le plus frequent. Seize patients (37 %) ont des « auto-anticorps associes aux myosites », la plus part du temps des anticorps anti-SSA/SSB, des anti-PM-Scl, anti-Ro, anti-U-RNP, anti-DNA natif. Frequemment les patients ont simultanement deux types d’auto-anticorps associes aux myosites : anti-SSA/SSB et anti-DNA natif et/ou anti-PM-Scl. L’EMG est pratique chez 33 patients (76,7 %), les donnees etant en faveur d’un syndrome myogene. On note une association des signes myogenes et neurogenes, ces derniers patients ont en general un syndrome de Gougerot-Sjogren associe. La biopsie musculaire a ete realisee chez 33 patients, donnees interpretees selon les criteres ENMC. Conclusion La reconnaissance d’une myosite chez le sujet âge ne differe pas fondamentalement de sa reconnaissance chez le sujet jeune. Il faut y penser et ne pas banaliser des manifestations de faiblesse, fatigue/asthenie, intolerance a l’effort ou les attribuer trop vite a des causes medicamenteuses. Les caracteristiques cliniques des patients âges sont comparables avec celles de patients plus jeunes. Le dosage des creatines kinases est un element important et renseigne sur la souffrance objective du tissu musculaire, mais les CPK tendent a etre moins elevees avec l’âge [1] . Les caracteristiques serologiques sont similaires chez les patients âges, des auto-anticorps specifiques ou associes aux myosites sont presents de facon concordante avec les donnees de la litterature [2] . Les maladies auto-immunes sont representees de maniere similaire au sein de notre population de patients âges par rapport a la population generale de myosites [3] . L’incidence des cancers augmente avec l’âge et sont en premier lieu observes chez les patients ayant une dermatomyosite. Aucune pathologie neoplasique specifique n’est liee a la myopathie inflammatoire, dans notre observation les cancers sont plus souvent observes chez les femmes et les cancers gynecologiques (sein, ovaire) predominent. La corticotherapie est le traitement le plus frequemment utilise. L’utilisation des autres immunosuppresseurs est influencee par la severite des symptomes extra-musculaires et en premier lieu par l’atteinte pulmonaire. Les problemes importants des myosites chez les sujets âges sont donc d’ordre etiologique, diagnostique et therapeutique.

Additional data on the occurrence and distribution of Xiphinema non-americanum group species in Romania are provided. Xiphinema diversicaudatum, X. index, X. vuittenezi and X. italiae were recovered from vineyards and cherry fruit trees; adults and juvenile stages were described and analysed and the morphology/variability discussed. Multiplex PCR diagnostic test using species-specific primers designed by Wang et al. (2003) yielded amplification products with expected lengths for all screened populations of these four species. Two ribosomal markers (D2-D3 28 LSU rDNA and ITS) were sequenced and ITS RFLP patterns were obtained from two X. vuittenezi populations, which have shown some morphological differences. Comparatively low level of interpopulation genetic dissimilarity (

In this study we report for the first time that Yb2+ is an efficient and fast activator in iodide scintillator crystals. In both SrI2 and CsBa2I5, Yb2+ offers blue luminescence (λ max = 414 nm), light yield greater than 50,000 Photons/MeV and sub-microsecond decay time. Results on crystal growth and characterization will be presented.

In this study we review the state-of-the-art for double salt iodide scintillators, in particular cesium barium iodide (CBI), cesium calcium iodide (CCI) and barium bromine iodide (BBI), as well as report on their scintillation and optical properties. Double salt iodides inherently have high density and atomic number which translates to good stopping power for energetic particles, in particular gamma rays. Light yields of 54,000 ph/MeV for CBI, 51,000 ph/MeV for CCI, and 46,000 ph/MeV for BBI were measured. A FWHM energy resolution for the 662 keV full absorption peak was observed at 5.7% for CBI, 16.3% for CCI and 3.56% for BBI. The principal scintillation decay timing for CBI was 840 ns, 462 ns for BBI, and two distinct time components of 9 ns and 1900 ns were observed for CCI.

Numerical simulations of two-phase Darcy flows in heterogeneous porous media requires choosing an appropriate set of primary unknowns, which may be challenging, especially when dealing with very flat capillary pressure curves, dry regions or saturation jumps at the rock type interfaces. The classical approaches fail to cope with all of those difficulties. In particular the two-pressure formulation allows handling saturation jumps, but beaks down if the capillary pressure doesn’t depend on saturation. It also lacks robustness when dealing with nearly residual water saturations. On the other hand, for homogeneous medium, the pressure – saturation formulation is known to be robust when dealing with dry media and can handle vanishing or constant capillary pressure curves. Unfortunately it is not always possible to extend it to the case of discontinuous capillary pressure curves. In this paper, a new formulation based on parametrization techniques for the capillary pressure monotone graph extension is proposed which handles all the above mentioned difficulties while still using only two unknowns by degree of freedom. We illustrate the efficiency of our approach by numerous numerical experiments dealing with water gas flow in fractured tight gas reservoirs using the data set presented in [2]. Following [1], the fractures are modelled as interfaces of codimension one with continuous pressure at the matrix fracture interfaces. During the injection phase of the simulation, water penetrates only a few tens of centimetres deep in the matrix rock. Therefore, in order to obtain an accurate numerical approximation, an anisotropic refinement of the mesh is used in the neighbourhood of the fractures using prismatic elements. The connection with the surrounding tetrahedral mesh in the matrix domain is achieved using pyramids. Following [1], the model is discretized using the Vertex Approximate Gradient scheme which allows for general polyhedral cells. The numerical performance of the new approach is evaluated for various choices of capillary pressures curves. The comparison with classical formulations shows that the new approach is more efficient both in terms of Newton iterations and CPU time. [1] K.Brenner, M.Groza, C.Guichard, R.Masson: Vertex Approximate Gradient Scheme for Hybrid Dimensional Two-Phase Darcy Flows in Fractured Porous Media, M2AN, pp.49 2, 303-330, 2015. [2] D.Y.Ding, H.Langouet, L.Jeannin: Simulation of Fracturing Induced Formation Damage and Gas from Fractured Wells in Tight Gas Reservoirs, SPE 153255, 2012.

In this article we report the evaluation of thick (up to 10 mm) as-grown Cd0.9Zn0.1Te(CZT):In detectors fabricated from ingots grown by traveling heater method (THM). The crystals were investigated by mapping the electron mobility (μe), (μτ)e and the internal electric field of as-grown CZT samples. The detector performance was also evaluated in co-planar grid geometry. The excellent (μτ)e value and the detector performance of 10 mm thick as-grown detectors is the indication that the THM technique can be employed successfully to fabricate the detectors directly from the as-grown boule at substantially lower cost.

Europium-doped barium and strontium iodide crystals are high light yield scintillator materials with excellent energy resolution. In this communication, BaI2:Eu and SrI2:Eu single crystals with space groups of Pnma ( D 2 h 16 ) and Pbca ( D 2 h 15 ) respectively were grown from the vertical Bridgman method. The crystals were investigated with polarized Raman spectroscopy at temperatures varied from 77 to 300 K. The observed Raman-active modes for each crystal were assigned with the help of group theory analysis. It is found that the absence of the site symmetry leads to splitting of a spectral line in Pnma structure into two lines in the Pbca structure. Structural defects including dark spots formed during crystal growth and new species produced from hydration were characterized.

We report the scintillation properties of both KPb 2 Cl 5 and K 2 CeCl 5 grown by vertical Bridgman method from synthesized and zone refined material. Both crystals exhibit minimal hygroscopic properties, which is desirable in applications where hermitization is not feasible. The KPb 2 Cl 5 crystal, doped with 2.5 mol% of EuCl 2 , appeared yellow in color and did not scintillate, while the self activated transparent K 2 CeCl 5 did. The energy resolution and decay time at 662 keV were measured to be 6.1% and 78 ns respectively, with a light yield of 31,000 photons/MeV.

We have developed a procedure to purify, synthesize and grow InI single crystals using the Bridgman technique. The commercial product of InI from Alfa Aesar (99.998% InI or 4 N) was zone refined by 50 passes of a zone-heater at 420 °C, traveling at 2 cm/h (the melting point of InI is 360 °C). InI was also synthesized using high purity In and I 2 by vapor transport technique. The grown InI single crystal showed a clear band edge excitonic emission around 2.02 eV at 6 K using photoluminescence measurement. The resistivities of InI detectors were found to be ∼2×10 9 and 1×10 8 Ω cm for zone refined and vapor synthesized starting materials, respectively. The InI detector formed by Pd–Pd contact showed clear peak of alpha particle detection at room temperature using 241 Am source.

This work focuses on the 3. Resultsanddiscussioncharacterization of 10×10×10 mm 3 THM-grown CdZnTe detector-grade crystals that have been post-growth annealed to remove the secondary phases (SPs). All three detectors showed an average energy resolution of ∼1.63% for a small guarded pixel with 3.5 mm diameter, measured using 137 Cs—662 keV with an average peak-to-Compton ratio of 2.7. The characterization showed vestiges of SPs and micro-twins present in some of the crystals indicating that the SPs prior to annealing were large and had size in the range of 100–500 μm. The various detectable structural features, such as micron twins, strains and sub-micron level of Te inclusions seemed to have little or no influence in the radiation spectrometer performance of the detectors; this is possibly because they are either having low density or electrically inactive.

The concentration, size and spatial distribution of Te inclusions in the bulk of CdMnTe crystals mined from two batches of ingots were studied. An isolated planar layer decorated with Te inclusions was identified in CdMnTe crystals from the second ingot. The internal electric field of a CMT crystal was probed by infrared (IR) imaging employing Pockels electro-optic effect. The effect of an isolated plane of Te inclusions on the internal electric-field distribution within the CdMnTe crystal was studied. Space charge accumulation around the plane of Te inclusions was observed, which was found to be higher when the detector was reverse-biased. The effects of the plane of Te inclusions on the electric-field distribution within the CdMnTe crystal, and the quality of CdMnTe crystals for nuclear detector applications are discussed.

Synthetic Cd1–xZnxTe or “CZT” crystals are highly suitable for γ-spectrometers operating at room temperature. Secondary phases (SP) within CZT, presumed to be Te metal, have detrimental impacts on the charge collection efficiency of fabricated device. Using analytical techniques rather than arbitrary theoretical definitions, we identify two SP morphologies: (i) many void, 20-μm “negative” crystals with 65-nm nanoparticle residues of Si, Cd, Zn, and Te and (ii) 20-μm hexagonal-shaped bodies, which are composites of metallic Te layers with cores of amorphous and polycrystalline CZT material that surround the voids.

The paper presents experimental results concerning the age importance of the first freshening of the ewes belonging to the Botosani Karakul breed. Some females were mated at an early age (8-9 months old) and others at the normal physiological age (16-18 months old). The influence of early pregnancy and of the one in due time on the production parameters (body weight, body growth and milk production and their evolution, bodily dimensions, lamb pelt features) and reproduction indicators (heat apparition rhythm, their manifestation rate, freshening number in order to the pregnancy be installed, fecundity, prolificacy) was yearly pursued next to 3.5-4 years old. The experimental results point out that the age of the first freshening in the Botosani Karakul sheep (early mating or mating at normal physiological age) does not influence or unsignificantly influences the morpho-production parameters and reproduction indices of the adult animal. But, forwarding the reproduction activity of ewes with an year, a gain of lamb number and of milk production is obtained on the whole productive period of ewes, thus contibuting to streamlining the economic situation of sheep farms specializated for the lamb pelt production.

The paper proposes a simplified formula to estimate the milk production in sheep. The formula is based on using the polynomial of Hermite interpolation of 0 degree. The result constitutes a control value for the milk production parameter. This value is well correlated with the correctly calculated value by a polynomial interpolation of superior degree.

The paper describes some associative aspects of various biochemical-genetic markers with the reproduction activity in ewes of the Botosani Karakul breed. The two most important reproduction parameters (fecundity and prolificacy) were analyzed according to the genotypes or phenotypes of polymorph systems (haemoglobin, transferrin, albumin and blood potassium) of females. The relationship between reproduction data and genetic markers in ewes was quantified both for each genotype (phenotype) and for each mating couple type made up depending on the genotype (phenotype) of the couple partners (homozygous x homozygous, homozygous x heterozygous or heterozygous x heterozygous). All these associative aspects and their results are discussed for each polymorph genetic system. The ewes which are heterozygous at different genetic marker loci are more fertile and more prolific than the ewes which are homozygous at the levels of these loci. The highest conception and lambing rates resulted from the mating couples in which both partners were heterozygous and the least lambs were obtained from the mating couples in which both partners were homozygous; the fertility and prolificacy had intermediate values in heterogeneous mating couples (heterozygotes x homozygotes) but they were nearer to the case in which both mating couple partners were heterozygous. The sheep breeding field can benefit by the contribution of biochemical-genetic markers to optimize the selection criteria with a view to increasing the reproduction capacity of this species.

In the last ten years the milk lambs were very demanded on the west European market, especially at the beginning of December and early spring. In this researches was followed the growing speed evolution on crossbreed Charollais x Merinos de Transilvania lambs, from lambing to weaning (70 days). Mother sheep were well prepared before get trough a normal nutrition, depending on the phase of gestation and adequate sheltering conditions. At lambing, sheep had a very good condition and a normal milk production. Crossbreed lambs had maternal milk on ad libitum and from the age of 10 days got in separated enclosures, quality after-grass and granulated combined feeder with 14% PDI in the first 30 days and 12% between 30- 70 days. After the evaluation of the growing speed it was determined that lambs from single lambing, both sexes (F-female, M-male), realize a growing speed, between lambing to weaning (70 days) superior (370g/day), the ones from twin lambing (F-F couple 286g/day, F-M couple 299g/day, M-M couple 302g/zi). The growing speed is significantly higher (p < 0.01) in 30-70 days period, compared with 10-30 days period, both in lambs from single and twin lambing. On the base of this study, we suggest that for obtaining milk lambs with a higher body weight and quality meat, realization of crossbreed lambs between breeds Charollais and Merinos de Transilvania, is opportune. This should be raised with maternal milk and strong feeder, at least until the age of 70 days.

Cesium cerium bromide (Cs2CeBr5) and potassium cerium bromide (K2CeBr5) are new scintillator materials for X-ray and gamma ray detector applications. Recently halide scintillator materials, such as Ce doped lanthanum bromide has been proved to be very important material for the same purpose. These materials are highly hygroscopic; a search for high light yield non-hygroscopic materials was highly desirable to advance the scintillator technology. In this paper, we are reporting the crystal growth of novel scintillator materials, cesium cerium bromide (Cs2CeBr5) and potassium cerium bromide (K2CeBr5). Crystals were successfully grown from the melt using the vertical Bridgman-Stockbarger technique, in a comparison with the high performance LaBr3 or LaCl3 crystals, cerium based alkali halides crystals, (Cs2CeBr5) and (K2CeBr5) have similar scintillation properties, while being much less hygroscopic. Furthermore, cesium based compounds will not suffer from the self-activity present in potassium and lanthanum compounds. However the Cs2CeBr5 crystals did not grow properly probably due to non-congruent melting or to some phase transition during cooling. Keywords." Scintillator materials; Ce3+; Energy resolution; Light yield; K2CeBr5

The associative analysis of the potassium phenotypes with the quantitativeproduction traits in adult sheep of the Botoşani Karakul breed pointed out theproduction superiority of the HK phenotype in rams concerning the both bodyweight and wool production. The ewes with HK phenotype are slightly moreproductive than the LK ewes concerning the wool production. The productionsuperiority of the LK phenotype was found in females for body weight and totalmilk quantity. Statistically, the difference values of the quantitative productionsbetween the two potassium phenotypes are very close to the 5% significancethreshold in the adult rams and insignificant in the adult ewes. The utilization ofthe kalium system in sheep breeding of the Botoşani Karakul breed forquantitative productions must be made with accuracy because the association ofthe LK phenotype with the qualitative features of the lamb pelts and with thehealth status is better than with the HK phenotype.

In the paper it emphasizes the importance of inheritance of colour variation and ofbreeding problems, important traits affecting the price of the production fur traits.It is therefore an attempt to highlight those aspects which can make an impact onthe improvement in Karakul pelt production. From an economic point of view, ithas been shown by various authors that within different colours, the pelt price ispredominantly determined by curl type, pattern score, hair quality score and hairlength traits. Traits such as pelt thickness and hair thickness are also correlated tothe price, though their contributions are minimal. It was furthermore indicated thatthe relative weight for pattern score becomes less important and for hair qualityscore it becomes more important with a decrease in curl development. Propertiessuch as colour intensity become more important in the coloured pelts.

We report the scintillation properties of a new material, K 2 CeCl 5 , which was grown by vertical Bridgman technique. Under excitation of 4.5 MeV α-particles, the Ce 3+ emission had a single peak centered at 370 nm with a width of 20 nm. The scintillation light output was estimated to be ∼30,000 photons/MeV for γ excitation at 662 keV and ∼24,000 photons/MeV γ equivalent (assuming an α/γ ratio of 0.34) under α excitation. The smaller light yield for α s can be partly explained by surface damage of the sample during polishing and subsequent partial oxidation of the Ce luminescence centers. The energy resolution at 662 keV was measured to be about 5.8%. Importantly, K 2 CeCl 5 is found to be much less hygroscopic than lanthanum halide scintillators and may therefore preferred in applications where enclosing the material is not feasible.

MRI should be performed in the presence of an acute febrile urinary retention, when septic and obstructive causes are eliminated. We report a case of post-infectious probable acute disseminated encephalomyelitis (ADEM) with a mostly spinal cord tropism of involving Campylobacter.A 32-year-old man with no medical history was admitted for an acute febrile urinary retention. He reported severe diarrhea 3 days before. Clinical course was then complicated by a progressive tetraparesis predominating in the lower limbs. Medullar MRI showed thoracic myelitis. A five-day course of intravenous corticosteroids allowed a full recovery of both the motor and urinary symptoms. Fecal culture isolated Campylobacter sp. Final diagnosis was post-bacterial ADEM.Clinical findings and MRI allow clinicians to suspect acute disseminated encephalomyelitis. This hypothesis implies to actively look for recent infections or vaccinations preceding the clinical presentation.

Selected possible applications of (Cd, Mn)Te, a classical wide-bandgap semimagnetic semiconductor, will be described. Both the semimagnetic character and the other physical properties of this material give rise to its wide applications. As a semimagnetic semiconductor (Cd, Mn)Te demonstrates “giant Faraday rotation” (of the direction of polarization in a strong static magnetic field) for photons with energy a little below that of the free exciton energy. This effect, which is strongest at low temperatures, is also significant at room temperature. (Cd, Mn)Te-based “Faraday rotators” can be used in optical telecommunications as “optical isolators” between the source of radiation (a strong laser) and the rest of the optical transmission line to avoid having parasitic light reflected back to the laser and disturbing its operation. In (Cd, Mn)Te crystals the Faraday effect is extremely fast. The results of the experiments, showing that the response time of the (Cd, Mn)Te crystals to a pulsed magnetic field is in the range 300–500 fs, will be presented, as well as the possible applications of this super-fast Faraday effect. As a wide-bandgap semiconductor with high stopping power for X- and γ-rays, (Cd, Mn)Te can be applied to the construction of radiation detectors. The required parameters: high resistivity (∼10 10 Ω cm) and a high mobility–lifetime product ( μτ = 3 × 10 −3 cm 2 /V) have already been achieved and the results will be described.

Cd1−xZnxTe (CZT) crystals grown from a modified vertical Bridgman technique were characterized by means of an optical polarized transmission technique using the Pockels effect, low-temperature direct current (DC) photo-conductivity technique, low-temperature photoluminescence (PL) spectroscopy, room-temperature PL mapping technique, and detector performance measurements. Electric field mapping indicates that an approximation of a uniform electric field distribution approximation is generally satisfied for CZT detectors operated at room temperature under typical working conditions. A nonuniform electric field distribution is observed under intense infrared (IR) light illumination, and a model is proposed based on charge generation of defects, trapping, and space-charge effects. The largest hole mobility-lifetime product (μτ)h of the CZT detector measured by DC photoconductivity is 7.0 × 10−4 cm2/V. The detector treated with 2% bromine in methanol chemical etch has a relatively small surface recombination velocity at room temperature, which was obtained from DC photocurrent and detector performance tests, as measured by irradiation of 5.5-MeV α particles and 59.6-keV γ-rays, respectively. We have clearly shown the equivalence of charge collection efficiency results measured by both DC photocurrent and α particle response. Low-temperature DC photocurrent measurements show that surface recombination velocity increases significantly with decreasing temperature from 300 K to 250 K. The effective electron mobility-lifetime product—combination effects of bulk and surface of CZT crystal—increases with increment of temperature. Room-temperature PL mapping measurements indicate uniformity of zinc concentration within CZT crystals. Low-temperature PL spectroscopy shows that the dominant emission peaks are excitons, which are bound to either shallow neutral donors (D0, X) or neutral acceptors (A0, X), depending on the temperature, concentration of donors and acceptors, and the incident light intensity. It was found that the luminescence of (D0, X) depends linearly on the incident laser intensity, while (A0, X) has a nonlinear dependence.

Surface-enhanced Raman scattering (SERS) has been studied using a silver-coated porous glass-ceramic material as a new type of substrate. The porous glass-ceramic is in the CaO–TiO2–P2O5 system prepared by controlled crystallization and subsequent chemical leaching of the dense glass-ceramic, leaving a solid skeleton with pores ranging in size from 50 nm to submicrometer. Silver was coated on the surface of the porous glass-ceramic by radio frequency (RF) sputtering or e-beam evaporation in vacuum. SERS spectra of excellent quality were obtained from several dyes and carboxylic acid molecules, including rhodamine 6G, crystal violet, isonicotinic acid, and benzoic acid, using this new substrate. This new substrate showed a good compatibility with these molecules. The porous glass-ceramic with a nanometer-structured surface accommodated both test molecules and silver film. The absorbed molecules were therefore better interfaced with silver for surface-enhanced Raman scattering.

To answer the title question – the technology and properties of the (Cd,Mn)Te crystals is discussed as compared with those of the more commonly used (Cd,Zn)Te crystals. The composition homogeneity of the large single crystals of the ternary compound seems to be easier to achieve in the case of (Cd,Mn)Te because the segregation coefficient of Mn in CdTe is negligible with respect to that (approx. 1.3) of Zn. Only 15% of MnTe has to be added to CdTe to reach the best for the detector application value of the energy gap (in the range 1.7–2.2 eV), while the necessary amount of ZnTe is over 30%! This is because the composition dependence of the CdTe energy gap is for Mn twice as strong as for Zn. Using a smaller amount of the second cation diminishes many alloying-related problems. Dopant-free as grown (Cd,Mn)Te crystals are of p-type, which is related to the Cd vacancies acting as acceptors. The number of vacancies can be reduced by the post-growth annealing in the Cd vapours and the high (∼1010 Ωcm) resistivity, required for good detectors, can be obtained by doping with donors. The technology of the (Cd,Mn)Te crystals, undoped and compensated in the very large range of concentrations, and Cd-annealing of the samples is discussed. Characterization of the obtained crystals is described. The behaviour of the preliminary detectors is shown. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Cadmium zinc telluride (CZT) is one of the most promising materials for large-volume gamma-ray spectrometers and imaging arrays. However, because of deficiencies in the high quality material, high-resolution CZT spectrometers are still limited to relatively small dimensions (

The effects of polishing on the electron mobility-lifetime product of a detector-grade Cd/sub 1-x/Zn/sub x/Te (CZT) crystal is reported. The two surfaces of the crystal were deposited with Au layers and illuminated with subband light. A direct current (dc) photocurrent technique was used to measure the electron mobility-lifetime product as a function of the illuminating power. The measured dependence of the electron mobility-lifetime product on the photogenerated electron concentration was highly affected by the condition of the irradiated surface. This discovery has important implications for processing of CZT surfaces for radiation detector applications.